2024/10/04 更新

写真a

オオノ ノリヤス
大野 哲靖
OHNO, Noriyasu
所属
大学院工学研究科 電気工学専攻 先端エネルギー 教授
大学院担当
大学院工学研究科
学部担当
工学部 電気電子情報工学科
職名
教授
連絡先
メールアドレス

学位 1

  1. 博士(理学) ( 1995年   九州大学 ) 

研究キーワード 5

  1. プラズマーガス相互作用

  2. プラズマー固体相互作用

  3. 核融合

  4. プラズマ

  5. プラズマーガス相互作用

研究分野 4

  1. エネルギー / プラズマ科学  / 非線形現象,カオス,波動,原子分子過程

  2. エネルギー / プラズマ応用科学  / 表面改質,ナノ構造

  3. エネルギー / 核融合学  / ダイバータ,周辺プラズマ,プラズマ-壁相互作用

  4. エネルギー / プラズマ科学  / 非線形現象,カオス,波動,原子分子過程

現在の研究課題とSDGs 2

  1. プラズマを用いた機能性材料創成

  2. 磁場閉じ込め核融合発電実現のための周辺プラズマ制御

経歴 11

  1. 名古屋大学   低温プラズマ科学研究センター   センター長

    2023年4月 - 現在

      詳細を見る

    国名:日本国

  2. 東海国立大学機構   低温プラズマ科学総合研究拠点   拠点長

    2023年4月 - 現在

      詳細を見る

    国名:日本国

  3. 名古屋大学   大学院工学研究科 附属プラズマナノ工学研究センター   センター長

    2017年4月 - 2019年3月

  4. 名古屋大学   工学研究科   教授

    2008年4月 - 現在

  5. 名古屋大学   工学研究科   教授

    2008年4月 - 現在

  6. 名古屋大学   エコトピア科学研究所   助教授

    2005年4月 - 2008年3月

  7. 名古屋大学   理工科学総合研究センター   助教授

    2003年4月 - 2005年3月

  8. 名古屋大学   工学研究科   助教授

    2002年2月 - 2003年3月

  9. 名古屋大学   工学部   講師

    1995年4月 - 2002年1月

  10. 名古屋大学   工学部   助手

    1990年10月 - 1995年3月

  11. 長崎大学   工学部   助手

    1988年4月 - 1990年9月

      詳細を見る

    国名:日本国

▼全件表示

学歴 4

  1. 九州大学   総合理工学研究科博士課程   高エネルギー物質科学専攻

    1997年4月 - 1998年3月

  2. 九州大学   総合理工学研究科博士課程   高エネルギー物質科学専攻

    1987年4月 - 1988年3月

  3. 九州大学   総合理工学研究科修士課程   高エネルギー物質科学専攻

    1985年4月 - 1987年3月

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    国名: 日本国

  4. 九州大学   理学部   物理

    1981年4月 - 1985年3月

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    国名: 日本国

所属学協会 3

  1. プラズマ・核融合学会

  2. 日本物理学会

  3. 電気学会

委員歴 94

  1. プラズマ・核融合学会   プラズマ・核融合学会広報委員  

    2023年7月 - 2025年6月   

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    団体区分:学協会

  2. 量子科学研究開発機構炉心プラズマ共同企画委員会   委員  

    2022年5月 - 2023年3月   

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    団体区分:その他

  3. 筑波大学プラズマ研究センター運営協議会   委員  

    2022年4月 - 2024年3月   

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    団体区分:その他

  4. 核融合科学研究所PWI国内技術委員会   委員  

    2022年4月 - 2024年3月   

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    団体区分:その他

  5. 東北大学量子エネルギー材料科学国際研究センター共同利用委員会委員および採択専門委員会   委員  

    2022年4月 - 2024年3月   

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    団体区分:その他

  6. 核融合科学研究所運営会議外部評価委員会   委員  

    2021年6月 - 2023年3月   

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    団体区分:その他

  7. 大学改革支援・学位授与機構国立大学教育研究評価委員会   専門委員  

    2020年2月 - 2021年3月   

  8. 量子科学研究開発機構核融合エネルギーフォーラム   委員  

    2020年1月 - 2024年3月   

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    団体区分:その他

  9. 核融合科学研究所運営会議   委員  

    2019年5月 - 2023年4月   

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    団体区分:その他

  10. 九州大学附属高温プラズマ理工学研究センターQUEST実験推進会議   委員  

    2019年4月 - 2023年3月   

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    団体区分:その他

  11. 文部科学省科学技術・学術審議会専門委員会   委員  

    2019年4月 - 2023年2月   

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    団体区分:政府

  12. XXXIV International Conference on Phenomena in Ionized Gases and 10th International Conference on Reactive Plasmas   ICRP International Organizing Committee  

    2018年10月 - 2019年7月   

      詳細を見る

    団体区分:学協会

  13. 核融合エネルギーフォーラムダイバータ研究開発加速戦略方策検討評価ワーキンググループ   専門委員  

    2018年10月 - 2019年3月   

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    団体区分:その他

  14. 核融合科学研究所運営会議次期計画検討委員会   委員  

    2018年9月 - 2019年4月   

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    団体区分:その他

  15. 筑波大学プラズマ研究センター双方向型共同研究審査委員会   委員  

    2018年4月 - 2023年3月   

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    団体区分:その他

  16. 東北大学金属材料研究所附属量子エネルギー材料科学国際研究センター共同利用委員会   委員  

    2018年4月 - 2020年3月   

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    団体区分:その他

  17. ISPlasma 2019/IC-PLANTS2019組織委員会   委員  

    2018年4月 - 2019年3月   

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    団体区分:学協会

  18. 一般社団法人プラズマ・核融合学会   領域長  

    2018年1月 - 2018年12月   

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    団体区分:学協会

  19. ISPlasma 2018/IC-PLANTS2018組織委員会   プログラム委員、組織委員  

    2017年11月 - 2018年3月   

      詳細を見る

    団体区分:学協会

  20. 核融合科学研究所運営会議外部評価委員会   委員  

    2017年9月 - 2019年3月   

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    団体区分:その他

  21. 核融合エネルギーフォーラム専門委員会   専門委員  

    2017年9月 - 2018年3月   

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    団体区分:その他

  22. 日本学術振興会特別研究員等審査会および国際事業委員会   審査員  

    2017年8月 - 2018年7月   

      詳細を見る

    団体区分:学協会

  23. 日本学術振興会 特別研究員等審査会   専門委員  

    2017年8月 - 2018年7月   

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    団体区分:その他

  24. 日本学術振興会 国際事業委員会   書面審査員・書面評価員  

    2017年8月 - 2018年7月   

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    団体区分:その他

  25. 日本学術振興会 卓越研究員候補者選考委員会   書面審査員  

    2017年8月 - 2018年7月   

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    団体区分:その他

  26. プラズマ技術産業応用センター運営会議   委員  

    2017年7月 - 2018年3月   

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    団体区分:自治体

  27. 第12回核融合エネルギー連合講演会組織委員会   委員  

    2017年6月 - 2018年12月   

      詳細を見る

    団体区分:学協会

  28. 核融合科学研究所運営会議   委員  

    2017年5月 - 2019年4月   

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    団体区分:その他

  29. 自然科学研究機構核融合科学研究所運営会議   委員  

    2017年5月 - 2019年4月   

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    団体区分:その他

  30. 中部電力株式会社電力技術研究会電源専門部会   専門委員  

    2017年4月 - 2023年3月   

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    団体区分:その他

  31. 九州大学附属高温プラズマ理工学研究センターQUEST実験推進会議   委員  

    2017年4月 - 2019年3月   

      詳細を見る

    団体区分:その他

  32. 中部電力 電力技術研究会電源専門部会   専門委員  

    2017年4月 - 2019年3月   

      詳細を見る

    団体区分:その他

  33. 核融合科学技術委員会   科学技術・学術審議会専門委員  

    2017年4月 - 2019年2月   

      詳細を見る

    団体区分:政府

  34. 科学技術・学術審議会専門委員会   専門委員  

    2017年3月 - 2019年2月   

      詳細を見る

    団体区分:政府

  35. 核融合科学研究所日米次期共同プロジェクト推進小委員会   委員  

    2017年1月 - 2018年3月   

      詳細を見る

    団体区分:その他

  36. 量子科学技術研究開発機構核融合エネルギーフォーラム専門委員会   専門委員  

    2016年10月 - 2017年3月   

      詳細を見る

    団体区分:その他

  37. 日本原子力研究開発機構核融合エネルギーフォーラム   専門委員  

    2015年8月 - 2016年3月   

  38. プラズマ・核融合学会広報委員会   広報委員  

    2015年7月 - 2017年6月   

  39. 日本原子力研究開発機構炉心プラズマ共同企画委員会プラズマ実験・システム開発専門部会   専門委員  

    2015年6月 - 2016年3月   

  40. 核融合科学研究所運営会議   委員  

    2015年5月 - 2017年4月   

  41. 文部科学省科学技術・学術審議会   専門委員  

    2015年3月 - 2017年2月   

  42. 核融合科学技術委員会   委員  

    2015年3月 - 2017年2月   

  43. 日本学術振興会科学研究費委員会   専門委員  

    2014年12月 - 2015年11月   

  44. 学会現地実行委員  

    2013年4月 - 2015年3月   

  45. 国際会議国際組織委員  

    2012年9月 - 2013年3月   

  46. JT-60改修計画及び炉心プラズマ共同企画委員会   専門委員 JT-60SA専門部会  

    2012年7月 - 2013年3月   

  47. 国際会議国際組織委員  

    2012年5月 - 2013年3月   

  48. The 23rd International Toki Conference(ITC-23)   International Advisory Committee  

    2012年5月 - 2013年3月   

  49. TEXTOR国内技術委員会   委員  

    2012年4月 - 2014年3月   

  50. ISPlasma2013プログラム委員会   委員  

    2012年4月 - 2013年3月   

  51. 九州大学附属高温プラズマ力学研究センターQUEST実験推進会議   委員  

    2012年4月 - 2013年3月   

  52. ISPlasma2013組織委員会   委員  

    2012年4月 - 2013年3月   

  53. 核融合科学研究所運営会議外部評価委員会専門部会   専門委員  

    2011年10月 - 2012年3月   

  54. 平成23年度炉心プラズマ共同企画委員会   専門委員 JT-60SA専門部会  

    2011年8月 - 2012年3月   

  55. プラズマ・核融合学会企画第2小委員会   委員  

    2011年7月 - 2013年6月   

  56. 核融合科学研究所運営会議共同研究委員会   委員  

    2011年6月 - 2013年4月   

  57. ISPlasma2012組織委員会   委員  

    2011年4月 - 2012年4月   

  58. ISPlasma2012プログラム委員会   委員  

    2011年4月 - 2012年4月   

  59. 日米次期共同プロジェクト推進小委員会   委員  

    2011年2月 - 2012年3月   

  60. プラズマ・核融合学会 Plasma and Fusion Research   常務エディタ  

    2010年12月 - 2012年11月   

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    団体区分:学協会

  61. 筑波大学プラズマ研究センター双方向型共同研究審査委員会   委員  

    2010年7月 - 2012年3月   

  62. 平成22年度JT-60専門部会   専門委員  

    2010年6月 - 2011年3月   

  63. 21st International Toki Conference (ITC-21)   International Program Committee  

    2010年5月 - 2011年12月   

  64. TEXTOR国内技術委員会   委員  

    2010年4月 - 2012年3月   

  65. ISPlasma2011プログラム委員会   委員  

    2010年4月 - 2011年4月   

  66. ISPlasma2011組織委員会   委員  

    2010年4月 - 2011年4月   

  67. 核融合科学研究所運営会議共同研究委員会   委員  

    2009年6月 - 2011年4月   

  68. 炉心プラズマ共同企画委員会   専門委員(JT-60専門部会、JT-60SA専門部会)  

    2009年6月 - 2010年3月   

  69. 20th International Toki Conference(ITC-20)   International Program Committee  

    2009年5月 - 2010年12月   

  70. ISPlasma2010プログラム委員会   委員  

    2009年4月 - 2010年4月   

  71. ISPlasma2010組織委員会   委員  

    2009年4月 - 2010年4月   

  72. 国際トカマク物理活動(スクレイプ・オフ層及びダイバータの物理)   国際委員  

    2008年4月 - 現在   

  73. 電気学会 編集専門第3部会   委員  

    2008年4月 - 2010年3月   

      詳細を見る

    団体区分:学協会

  74. 18th International Toki Conference (ITC-18)   International Program Committee  

    2007年5月 - 2008年12月   

  75. 国際プログラム委員会委員  

    2007年4月 - 2008年3月   

  76. 国際組織委員会委員  

    2007年1月 - 2007年12月   

  77. 日本原子力研究開発機構 炉心プラズマ研究共同企画委員   専門委員  

    2006年10月 - 2007年3月   

  78. 日本原子力研究所「SOL及びダイバータに関する研究」   研究嘱託委員  

    2006年4月 - 2008年3月   

  79. 現地実行委員会委員  

    2006年4月 - 2007年3月   

  80. プラズマ・核融合学会   論文賞・技術進歩賞・学術奨励賞・産業技術賞選考委員  

    2006年4月 - 2007年3月   

  81. プラズマ・核融合学会 研究調査専門委員会   委員  

    2006年 - 2009年   

      詳細を見る

    団体区分:学協会

  82. プラズマ・核融合学会 論文賞・技術進歩賞・学術奨励賞産業技術賞選考委員会   委員  

    2006年   

      詳細を見る

    団体区分:学協会

  83. プラズマ・核融合学会企画委員会   企画委員・企画第2小委員会委員ーSSH活動  

    2004年9月 - 2007年6月   

  84. プラズマ・核融合学会企画委員会、企画第2小委員会   委員  

    2004年4月 - 2007年3月   

      詳細を見る

    団体区分:学協会

  85. 日本原子力研究所核融合研究委員会   専門委員  

    2003年6月 - 2005年9月   

  86. 日本物理学会 分科会(放電)   世話人  

    2002年4月 - 2004年3月   

      詳細を見る

    団体区分:学協会

  87. 日本物理学会分科会(放電)   世話人  

    2001年5月 - 2003年4月   

  88. 電気学会東海支部   「若手セミナー」世話人  

    2001年4月 - 2003年3月   

  89. 現地実行委員会委員  

    2001年4月 - 2002年3月   

  90. 現地実行委員会委員  

    2001年2月 - 2002年12月   

  91. 現地実行委員会委員  

    2001年2月 - 2002年12月   

  92. 現地実行委員会委員  

    1999年4月 - 2000年3月   

  93. プラズマ・核融合学会編集委員会   企画幹事  

    1997年7月 - 2000年3月   

  94. 現地実行委員会委員  

    1996年4月 - 1997年3月   

▼全件表示

受賞 5

  1. プラズマ・核融合学会賞技術進歩賞

    2020年12月   プラズマ・核融合学会   プラズマ・中性子照射材相互作用研究のための高密度プラズマ照射・試料解析装置の開発

     詳細を見る

    受賞区分:国内外の国際的学術賞  受賞国:日本国

  2. 平成29年度日本学術振興会特別研究員等審査会専門医委員(書面担当)表彰

    2018年7月   日本学術振興会  

     詳細を見る

    受賞国:日本国

  3. プラズマ・核融合学会論文賞

    2014年12月   プラズマ・核融合学会  

     詳細を見る

    受賞国:日本国

  4. 平成21年度JT-60U共同研究優秀賞

    2011年3月   (独)日本原子力研究開発機構  

     詳細を見る

    受賞国:日本国

  5. 第46回燃焼シンポジウムベストプレゼンテーション賞「ダブルプローブ法による大気圧酸素燃焼プラズマの電子特性評価」

    2008年12月   日本燃焼学会  

     詳細を見る

    受賞国:日本国

 

論文 650

  1. Four-dimensional conditional averaging tomography of rotating plasma ejection from cylindrical detached plasma 査読有り 国際誌

    Tanaka H., Kajita S., Natsume H., Ohno N.

    Scientific Reports   14 巻 ( 1 ) 頁: 9329   2024年12月

     詳細を見る

    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Scientific Reports  

    Detached plasma formation is a way to reduce the heat load on the wall in magnetic fusion devices. This study proposes a novel analysis technique consisting of the conditional averaging, sliding window, and tomography to reveal the spatiotemporal behavior of the rotating radial ejection event of detached plasma, which further contributes to local heat load reduction. The used equipment is a high-speed camera and an electrostatic probe located at the periphery of the linear plasma device NAGDIS-II. By applying this method, four-dimensional (4D) behavior of the emission structure along time (1D) and space perpendicular and parallel to the magnetic field (3D) was clarified; a rotating distorted structure appears as a precursor, which is then scraped and transported radially and axially. The proposed method is widely applicable to short-term rigid-body rotating structures, especially in linear plasmas.

    DOI: 10.1038/s41598-024-59182-5

    Scopus

    PubMed

  2. Machine learning aided line intensity ratio method for helium-hydrogen mixed recombining plasmas 査読有り 国際共著 国際誌

    Kajita S., Nishijima D., Fujii K., Tanaka H., Vernimmen J., van der Meiden H., Classen I., Ohno N.

    Plasma Physics and Controlled Fusion   66 巻 ( 10 ) 頁: 105005   2024年10月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma Physics and Controlled Fusion  

    The helium line intensity ratio (LIR) with the help of a collisional radiative (CR) model has long been used to measure the electron density, n e , and temperature, T e , and its potential and limitations for fusion applications have been discussed. However, it has been reported that the CR model approach leads to deviations in helium-hydrogen mixed plasmas and/or recombining plasmas. In this study, a machine learning (ML) aided LIR method is used to measure n e and T e from spectroscopic data of helium-hydrogen mixed recombining plasmas in the divertor simulator Magnum-PSI. To analyze mixed plasmas, which have more complex spectral shapes, the spectroscopy data were used directly for training instead of separating the intensities of each line. It is shown that the ML approach can provide a robust and simpler analysis method to deduce n e and T e from the visible emissions in helium-hydrogen mixed plasmas.

    DOI: 10.1088/1361-6587/ad6a81

    Scopus

  3. Hydrogen isotope effects on recombination dominant plasmas in NAGDIS-II 査読有り 国際共著 国際誌

    Shi J., Kaizawa H., Uematsu Y., Tanaka H., Kajita S., Ohno N., Sawada K., Ding H.

    Plasma Physics and Controlled Fusion   66 巻 ( 8 ) 頁: 085006(11 pp)   2024年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma Physics and Controlled Fusion  

    The detachment processes of the hydrogen (H) and deuterium (D) plasmas are comparatively investigated in the linear plasma device NAGDIS-II. The laser Thomson scattering measurements demonstrate that the recombination rate of the H plasma is greater than that of the D plasma as the neutral pressure increases in the molecular activated recombination (MAR) dominant detachment phase. As the recombination process by MAR is strongly dependent on the vibrational and rotationally excited states of the molecule, the rovibrational quantum state populations of the H and D molecules are measured using the Fulcher-α band spectroscopy. The results indicate that the vibrational temperature in the electronic ground state is considerably higher than the rotational temperature during detachment. The reaction rate coefficients for MARs due to charge exchange chains (CX-MAR) and dissociative attachment chains (DA-MAR) are calculated by the collision-radiation model under the measured temperature conditions. It can be observed that the CX-MAR is larger than the DA-MAR for both H and D, and that the CX-MAR of H is larger than the CX-MAR of D at electron temperatures T e above 1 eV. In consideration of the experimentally observed vibrational and rotational excitation temperatures, the reaction rate coefficients of CX-MAR and DA-MAR are increasing in the low T e region. These calculations are in accordance with the experimental results, which indicate that recombination processes due to MAR are more predominant in the H plasma compared to the D plasma. Furthermore, a transition from MAR to electron-ion recombination processes is observed in the D plasma at T e below 0.5 eV.

    DOI: 10.1088/1361-6587/ad59c4

    Scopus

  4. Germanium nanostructures by helium plasma irradiation 査読有り 国際誌

    Kajita S., Shi Q., Tabata K., Kuwabara T., Tanaka H., Ohno N.

    Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers   63 巻 ( 7 ) 頁: 07SP07   2024年7月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers  

    The effects of helium plasma irradiation, which has been widely studied on metals, on germanium have been experimentally investigated. The irradiation temperature ranges from 430 to 720 K, and the incident ion energy ranges from 30 to 100 eV. From the scanning electron microscope (SEM) observation, it was found that various morphological changes including pits, nanocones, nanopillars, and roughened surfaces occur. The spatial scale of the morphological change was analyzed by applying fast Fourier transform to SEM micrographs. Thermal desorption spectroscopy analysis suggests that He atoms implanted on Ge play major roles in forming roughened surfaces at a surface temperature higher than 500 K.

    DOI: 10.35848/1347-4065/ad5afe

    Scopus

  5. Lithography-Free Nanofabrication on Various Semiconductors by the Codeposition Etching Technique 査読有り 国際誌

    Shi Q., Kajita S., Ohno N., Tanaka H., Yasuhara R., Fujiwara H., Uehara H.

    Langmuir   40 巻 ( 24 ) 頁: 12437 - 12442   2024年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Langmuir  

    Nano-/microstructures can be formed with the aid of small amounts of impurities during deposition with noble gas plasma irradiation, which is referred to as codeposition etching. This can be a new method for lithography-free semiconductor nanofabrication. Here, the codeposition etching method was employed with argon plasma and molybdenum (Mo) impurities on various semiconductors. Structures can be formed only on substrates that have a lower sputtering yield than the seed impurity. The density, area, and height of structures are related to both the impurity deposition rate and the substrate material. Moreover, two mechanisms of impurity nucleation are proposed according to time dependence results for the formation of the structures.

    DOI: 10.1021/acs.langmuir.4c00686

    Scopus

    PubMed

  6. First results of multi-fluid modeling of detached hydrogen plasmas in a linear plasma device using fluid code LINDA-NU 査読有り 国際誌

    Sugiura K., Ido T., Tanaka H., Natsume H., Masuda S., Hoshino K., Sawada K., Ohno N.

    Contributions to Plasma Physics   2024;e202300150 巻   2024年6月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Contributions to Plasma Physics  

    In order to simulate hydrogen (H) plasma in the linear plasma device NAGDIS-II, we have modified the fluid code LINDA-NU to allow the simultaneous calculation of multiple ion species consisting of hydrogen atomic ions ((Formula presented.)) and molecular ions ((Formula presented.)). In this simulation, H and (Formula presented.) neutrals are assumed to be uniformly distributed in space in order to obtain initial qualitative results. The fraction of (Formula presented.) ions increases as the (Formula presented.) molecular density increases, and the recombination process between (Formula presented.) and electrons is observed to reduce the particle flux to the target plate. With an increase in H density, the electron density increases due to the decrease in ion flow velocity due to the change exchange process, and the electron temperature decreases to less than 1 eV, leading to the detached plasma formation attributed to the electron-ion recombination process.

    DOI: 10.1002/ctpp.202300150

    Scopus

  7. Tungsten fuzz growth at low temperatures (<900 K) on a surface with nanocones 査読有り 国際誌

    Shi Q., Kajita S., Ohno N.

    Nuclear Materials and Energy   39 巻   頁: 101668   2024年5月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    The tungsten (W) fuzzy structure was widely observed in linear plasma devices under the fusion-relevant condition. This type of structure can be used in many application fields benefiting from its larger surface area and high optical absorbance. However, W fuzz can be barely formed when the sample temperature is lower than 900 K. This study decreased the threshold to ∼800 K using W co-deposition on a Si nanocones substrate. It suggests that the conventional threshold temperature is only necessary for He bubble rupture to create a rough surface that induces the uneven trapping of the adatom diffusion.

    DOI: 10.1016/j.nme.2024.101668

    Scopus

  8. Surface modification of ZrC dispersion-strengthened W under low energy He plasma irradiation 査読有り 国際共著

    Li L., Liu Z., Chen Z., Yin C., Mao S., Wu X., Ohno N., Ye M.

    Nuclear Fusion   64 巻 ( 5 ) 頁: 56008   2024年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    ZrC dispersion-strengthened W exhibits high strength/ductility, low ductile-to-brittle transition temperature, and excellent thermal shock resistance, making it a promising candidate plasma-facing material for future fusion devices. In this study, surface modification of 0.5 wt.% ZrC dispersion-strengthened W (WZrC) under low energy and high fluence He plasma irradiation at high temperature was presented. Under the energy of 90 eV and fluence ranging from 6 × 1024 He·m−2-2 × 1026 He·m−2 He irradiation at 920 °C, a typical fuzz nanostructure appeared on the W matrix of WZrC. The thickness of fuzz layer is proportional to the square root of He irradiation fluence. The fuzz showed comparable thickness and structural features to pure W, indicating limited effects of the particle’s addition on resistance to high fluence He irradiation at high temperatures. Under continuous He injection, the fuzz would grow extending onto the particle area, making the particle obscured. Besides, the erosion behavior of particles under He plasma irradiation has been investigated, which is thought to be dominated by a sputtering process. Under the He influence of 6 × 1024 He·m−2, only nanopores were observed in the surface region. With fluence increasing to 5 × 1025 He·m−2, the surface became relatively uneven with larger holes. W aggregated in spots and distributed on the surface of the particle, which might be the result of subthreshold sputtering and deposition. When fluence further increased to 2 × 1026 He·m−2, the particles were eroded completely and covered by the extended fuzz, forming cavities. In addition, distinctive layered nanotendrils were observed above the cavities, which were characterized to consist of inner W-riched skeletons and outer Zr-riched layers. It indicates that the layered nanotendrils should be the result of fuzz extension combined with particle sputtering/deposition.

    DOI: 10.1088/1741-4326/ad2f4c

    Scopus

  9. Nanopatterning of Si surfaces by normal incident He plasma irradiation 査読有り

    Liu Z., Li L., Gao Z., Chen Z., Yin C., Mao S., Kajita S., Ohno N., Ye M.

    Applied Physics Letters   124 巻 ( 10 )   2024年3月

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    出版者・発行元:Applied Physics Letters  

    This study reports on the formation of self-organized silicon (Si) nanostructures by 75 eV helium (He) plasma irradiation at normal incidence without the presence of impurities. In contrast to the featureless surface after normal incidence argon (Ar) ion beam irradiation without the co-deposition of impurities, the Si surface exhibits the development of faceted nanostructures under 75 eV He plasma irradiation. The faceted structures are interspersed with valleys that extend in two orthogonal directions, imparting a mountain-like morphology to the surface. Our investigation verifies that the He bubbles align themselves along the direction perpendicular to the surface underneath these valleys. Furthermore, the presence of He bubbles induces distortion in the surface layer and leads to the formation of an amorphous Si layer. The underlying mechanism driving this surface evolution could be attributed to the instability induced by the presence of He bubbles.

    DOI: 10.1063/5.0186756

    Scopus

  10. Cone array formation on Si surfaces by low-energy He plasma irradiation with magnetron sputtering pre-deposited Ta 査読有り 国際共著

    Liu Z., Li L., Gao Z., Chen Z., Yin C., Mao S., Kajita S., Ohno N., Ye M.

    Journal of Applied Physics   135 巻 ( 9 ) 頁: 93302   2024年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Applied Physics  

    Low-energy ion beam irradiation, combined with the introduction of impurities, presents a promising approach for nanopatterning silicon (Si) surfaces. In this research, we investigate the surface evolution of Si (100) surfaces irradiated by 75 eV helium (He) plasma, in the presence of tantalum (Ta), traditionally regarded as an impurity incapable of initiating pattern formation, as evidenced in prior studies. The Ta impurities are pre-deposited onto the Si surfaces using the magnetron sputtering method, which offers a more controlled and quantifiable approach compared with the conventional co-deposition route. After irradiation at 800 K, dense cone arrays are produced on the Si surface. The growth of the cones is explored for fluence spanning (1-10) × 1025 m−2. The cross-sectional scanning electron microscope images indicate that the cone lengths and base width are well characterized by t1/2 dependence. The kinetics of the cone growth follow Fick’s law, characterized by an effective diffusive mechanism with the coefficients of diffusion: D = 6.49 ± 0.83 × 10−16 m−2 s−1. Transmission electron microscope observations reveal that the cone has distinct inner and outer parts with different microstructures and a clear interface. The growth mechanism of these cones is elucidated as a composite process involving preferential sputtering, the destabilizing influence of He bubbles, and the migration of adatoms.

    DOI: 10.1063/5.0187265

    Scopus

  11. Plasma-Driven Sciences: Exploring Complex Interactions at Plasma Boundaries 査読有り 国際誌

    Ishikawa K., Koga K., Ohno N.

    Plasma   7 巻 ( 1 ) 頁: 160 - 177   2024年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma  

    Plasma-driven science is defined as the artificial control of physical plasma-driven phenomena based on complex interactions between nonequilibrium open systems. Recently, peculiar phenomena related to physical plasma have been discovered in plasma boundary regions, either naturally or artificially. Because laboratory plasma can be produced under nominal conditions around atmospheric pressure and room temperature, phenomena related to the interaction of plasma with liquid solutions and living organisms at the plasma boundaries are emerging. Currently, the relationships between these complex interactions should be solved using science-based data-driven approaches; these approaches require a reliable and comprehensive database of dynamic changes in the chemical networks of elementary reactions. Consequently, the elucidation of the mechanisms governing plasma-driven phenomena and the discovery of the latent actions behind these plasma-driven phenomena will be realized through plasma-driven science.

    DOI: 10.3390/plasma7010011

    Scopus

  12. Thermal Conductivity Measurement of Fuzzy W Using a Thermoreflectance Method 査読有り

    Kajita S., Yagi T., Ohno N.

    IEEE Transactions on Plasma Science   Early Access 巻   頁: 1 - 6   2024年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Transactions on Plasma Science  

    Fuzzy nanostructured tungsten (W) is formed by helium (He) plasma irradiation. In fusion devices, the thermophysical properties are important to consider the response to pulsed heat load from the plasma. In this work, the thermal conductivity of the W fuzz is measured using a pulsed light heating thermoreflectance method. A detailed model was developed to explain the entire temporal evolution of the thermoreflectance signal. It was found that the thermal conductivity of the nanostructured layer was deduced to be in the range of 0.18%&#x2013;0.21% of the pure (ideal) W and lower than the previously reported highly porous metallic materials. In addition to the porosity, the specific nonuniform nanofiber structure is likely to contribute to the low effective thermal conductivity.

    DOI: 10.1109/TPS.2023.3348465

    Scopus

  13. Thermal response of nano-tendril bundles to steady heat load 査読有り 国際共著

    Xue Q., Tanaka H., Zhang R., Kajita S., Hori K., Shi Q., Kuwabara T., Ohno N.

    Japanese Journal of Applied Physics   62 巻 ( SN )   2023年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Japanese Journal of Applied Physics  

    Nano-tendril bundles (NTBs) are nanostructures formed on the surface of tungsten under helium plasma irradiation with impurities. Upon annealing, NTBs of different sizes exhibit distinct morphological changes. This study aims to elucidate the underlying reasons for the different morphological changes observed in NTBs through the analysis of their thermal responses. A simulation approach was employed to investigate the temperature distribution of NTBs with different heights, aspect ratios, and porosities during annealing experiments. The simulation results revealed varying degrees of impact of height, aspect ratio, and porosity on the temperature distribution of NTBs during annealing. This finding contributes to a better understanding of the thermal properties and reactions of NTBs.

    DOI: 10.35848/1347-4065/ace6ac

    Web of Science

    Scopus

  14. Transition from MAR to EIR of deuterium plasma detachment in NAGDIS-II 査読有り 国際共著

    Shi J., Kaizawa H., Tanaka H., Kajita S., Ohno N., Ding H.

    Physica Scripta   98 巻 ( 11 ) 頁: 115605   2023年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physica Scripta  

    Volumetric plasma recombination in a detached deuterium (D) plasma was experimentally studied in the linear plasma device NAGDIS-II. The radial distributions of the electron temperature (Te) and the electron density (ne) were measured by upstream and downstream laser Thomson scattering (LTS) systems and D-atom excited states of the Balmer series (n = 3-7) were measured by optical emission spectroscopy (OES). The results indicated that the electron static pressure, particle flux and heat flux present a two-step reduction with an increasing neutral pressure, suggesting that molecule activated recombination (MAR) and electron-ion recombination (EIR) were activated, respectively. The difference in the distributions of the atomic state population densities was observed to be a feature of the transition from the MAR-dominant phase to the EIR-dominant phase. The transition between the two phases had a distinct boundary at Te ∼0.7 eV, which was considered a transition point between the phases. The ratios of the atomic state population densities showed different features in the two phases, and are expected to be useful in characterizing the phase and degree of plasma detachment.

    DOI: 10.1088/1402-4896/acfeb4

    Scopus

  15. Application of machine learning for optical emission spectroscopy data in NAGDIS-II 査読有り

    Kajita S., Sakakibara T., Kaizawa H., Natsume H., Tanaka H., Fujii K., Ohno N.

    Fusion Engineering and Design   196 巻   頁: 114012   2023年9月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Fusion Engineering and Design  

    In this study, we applied machine learning to optical emission spectroscopy (OES) data and device parameters from the linear plasma device NAGDIS-II to explore the potential application of machine learning for predicting electron density, ne, and temperature, Te. The covered ranges of ne and Te, which were measured by an electrostatic probe, are 3.6 × 1017–2.4×1019 m−3 and 0.3–7.1eV, respectively. A three hidden layer neural network (NN) is introduced to model the relationship between ne/Te and the combination of line intensities, radial position, and device parameters. It is shown that the errors in ne and Te become 18.0 and 18.8%, respectively, which were almost the same level for the electrostatic probe, using all available data. Lasso regression and greedy algorithm are used to select the necessary line emissions. It is shown that four or five line intensities are sufficient to obtain almost the same quality as the one with all the other lines.

    DOI: 10.1016/j.fusengdes.2023.114012

    Scopus

  16. Fabrication of tungsten-based optical diffuser using fiberform nanostructure via efficient plasma route 査読有り 国際共著

    Feng S., Natsume H., Kajita S., Li E., Yasuhara R., Tokitani M., Tanaka H., Ohno N.

    Optics Express   31 巻 ( 16 ) 頁: 25438 - 25445   2023年7月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Optics Express  

    Optical diffusion is an essential process used to manage photons in a wide range of photoelectric systems. This work proposes an approach to fabricate novel optical diffusers by a plasma-processing technique, using fiberform nanostructures formed by helium plasma irradiation and subsequent annealing. After an annealing procedure in the air for oxidation, the optical properties and the light-diffusing abilities of these nanostructured thin films were studied. In addition to the morphology analysis and total transmittance measurement, the diffusion efficiency of the optical diffusers was analyzed using a transmitted scatter distribution function (TDF). It was revealed that the diffusion efficiency of a device with an irradiation time of 30 minutes could reach 97%. The results demonstrate the potential of these nanostructured optical diffusers for various photoelectric applications.

    DOI: 10.1364/OE.493993

    Web of Science

    Scopus

  17. Field emission properties of nano-tendril bundles formed via helium plasma exposure with various additional impurity gases 査読有り 国際共著

    Zhang R., Kajita S., Hwangbo D., Tanaka H., Feng S., Ohno N.

    Materials Research Express   10 巻 ( 5 ) 頁: 054002   2023年5月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Materials Research Express  

    Nano-tendril bundles (NTBs) were formed on tungsten via helium (He) plasma exposure with various additional impurity gases, such as neon (Ne), nitrogen (N2), and argon (Ar). The sizes of the NTBs showed different distributions with different additional impurity gases. The field emission property of the NTBs formed with various additional impurity gases was measured. The field-emission property was significantly affected by the morphology of the NTBs, especially the tips of the fibers. In the Ne- and Ar-seeded cases, the NTBs were formed with sharp tips, and the onset electric field for field emission was ∼1 kV mm−1 for all the NTB samples. The Ne-seeded samples showed the most rapid increase in the emission current. In the N2-seeded case, two types of NTBs were formed. The NTBs were formed with sharp tips when the ratio of N2 impurity gas was 2.1%. With an increase in the ratio to 3.0% or higher, the fibers of the NTBs became thicker and the tips became rounder. In the Fowler-Nordheim (F-N) plot analysis, the field enhancement factors were approximately 6000-7000 without significant differences, for all NTBs with sharp tips. NTBs with round tips showed totally different field emission property, as the emission current was only several μA, which is one-tenth of that for the other samples. This suggests that the local morphology of NTBs, especially the geometrical shape of the tips, and not the general size of NTBs, is the main factor in determining the field emission property of NTBs.

    DOI: 10.1088/2053-1591/acd1d4

    Web of Science

    Scopus

  18. Growth origin of large-scale fiberform nanostructures in He-W co-deposition environment 査読有り

    Hori K, Kajita S, Zhang R, Tanaka H, Ohno N

    Scientific reports   13 巻 ( 1 ) 頁: 5450   2023年4月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1038/s41598-023-32621-5

    PubMed

  19. Rapid growth of nanostructure on tungsten thin film by exposure to helium plasma 査読有り

    Feng S., Kajita S., Tokitani M., Nagata D., Ohno N.

    Plasma Science and Technology   25 巻 ( 4 ) 頁: 042001   2023年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma Science and Technology  

    A fiberform nanostructure was synthesized by exposing high-density helium plasma to a 100 nm thick tungsten thin film in the linear plasma device NAGDIS-II. After helium plasma exposure, the cross-section of samples was observed by a scanning electron microscope, transmission electron microscope, and focused ion beam scanning electron microscope. It is shown that the thickness of the nanostructured layer increases significantly for only a short irradiation time. The optical absorptivity remains high, even though it is exposed to helium plasma for a short time. The usage of the thin film can shorten the processing time for nanostructure growth, which will be beneficial for commercial production.

    DOI: 10.1088/2058-6272/ac9f2d

    Web of Science

    Scopus

  20. Erratum: Morphologies of co-depositing W layer formed during He plasma irradiation (International Atomic Energy Agency (2018) 58 (106002) DOI: 10.1088/1741-4326/aad24e) 査読有り

    Kajita S., Kawaguchi S., Yoshida N., Ohno N., Tanaka H.

    Nuclear Fusion   63 巻 ( 4 )   2023年4月

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    出版者・発行元:Nuclear Fusion  

    There are no changes to the fitting values in the original article.

    DOI: 10.1088/1741-4326/acbbde

    Web of Science

    Scopus

  21. Correlation of the Orthogonal Basis of the Core Plasma Distribution to the Divertor Footprint Distribution in LHD

    Tanaka H., Masuzaki S., Kawamura G., Hayashi Y., Kobayashi M., Suzuki Y., Mukai K., Kajita S., Ohno N.

    Plasma and Fusion Research   18 巻 ( 0 ) 頁: 2402021 - 2402021   2023年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    We have applied the multivariable analysis technique called the proper orthogonal decomposition (POD) to both the divertor particle flux distribution and the electron pressure distribution in the core region of LHD. The cross-correlation analysis indicates that 3rd, 4th, and 5th POD modes of the electron pressure distribution are highly correlated with the divertor footprint index which is a measure of where the peak position of the particle flux distribution is located on the inner divertor plate. Both the 3rd and 4th modes seem to correspond to the shift of the electron pressure peak position from the magnetic-axis radius. In contrast, 5th mode has a strong influence on the peripheral gradient of the electron pressure distribution. Their relationships with the divertor footprint could be explained by the finite β and the Pfirsch-Schlüter current effects.

    DOI: 10.1585/pfr.18.2402021

    Web of Science

    Scopus

    CiNii Research

  22. Study of the intermittent plasma structure around the divertor simulation experimental module in GAMMA 10/PDX 査読有り

    Tanaka H., Ezumi N., Sugiyama T., Gamo H., Shigematsu N., Yoshikawa M., Kohagura J., Hirata M., Togo S., Ohno N., Sakamoto M.

    Physics of Plasmas   30 巻 ( 3 ) 頁: 32501   2023年3月

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    掲載種別:研究論文(学術雑誌)   出版者・発行元:Physics of Plasmas  

    We have investigated the generation region of intermittent plasma structures, which could be due to the blob-like cross field transport around the divertor simulation experimental module (D-module) in the tandem mirror device GAMMA 10/PDX. A positive skewness of the ion saturation current was clearly seen when the electrode of the movable probe was located at the radial edge and just in front of the entrance limiter of the D-module. Fourier analysis and conditional averaging clarified that positive spikes intermittently appeared in the same region. This is the first indication that the phenomenon producing the high-density isolated plasma structures occurred in the upstream of the D-module. A negative skewness was also found, and large amplitude fluctuation was detected between regions showing positive and negative skewness. Furthermore, this and light emission fluctuations become stronger during the transient state from attached to detached state on the V-shaped target.

    DOI: 10.1063/5.0129886

    Web of Science

    Scopus

  23. Structural Correlation of Random Lasing Performance in Plasma-Induced Surface-Modified Gallium Nitride 査読有り

    Shi Q., Fujiwara H., Kajita S., Yasuhara R., Tanaka H., Ohno N., Uehara H.

    ACS Applied Optical Materials   1 巻 ( 1 ) 頁: 412 - 420   2023年1月

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    出版者・発行元:ACS Applied Optical Materials  

    The surface of GaN has been modified by a simple method that irradiates the substrate with Ar plasma and impurity codeposition, which is termed CoDE (Co-Deposition Etching). Unique structures were formed by the assistance of a small amount of Mo deposition without degradation of the crystal structure. The size of protrusions on the structure is influenced by the amount of deposited Mo particles. The mechanism for the structure formation is discussed based on transmission electron microscopy (TEM) observations and energy dispersive X-ray spectroscopy (EDS) measurements. Based on the GaN surface roughness, we have demonstrated random laser action in the UV region under photoexcitation. The lowest threshold (0.06 J/cm2) for random lasing was observed where the size of the structure is larger than 0.05 μm2, which was formed under conditions with the least amount of deposition. The correlation between the submicro/nanosize structures generated by plasma irradiation and lasing was evaluated in detail. The critical parameter to optimize the random lasing was determined to be the size of structures that can be modified by the Mo deposition rate. The results confirmed that the emission properties can be controlled by the processing conditions. This random laser fabrication technique is expected to be widely applicable to various direct-bandgap compound semiconductors.

    DOI: 10.1021/acsaom.2c00085

    Scopus

  24. Motion analysis of arc spots on tungsten fuzz by means of self-avoiding random walk model 査読有り

    Hwangbo D., Nishijima D., Kajita S., Ohno N.

    Japanese Journal of Applied Physics   62 巻 ( SA ) 頁: SA1007   2023年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Japanese Journal of Applied Physics  

    Arc spot motions on nanostructrued “fuzz” tungsten surfaces are investigated on the basis of a two-dimensional Monte Carlo random walk simulation. To compare with previous experimental results, the effects of self-avoiding, bifurcation and extinction of arc spots, as well as the fuzz thickness dependence, are included in the simulation. Under a given temporal arc current profile which is set as close as possible to the experiment, the results derived from the simulation reveal that the motion and the number of arc spots depend significantly on the fuzz thickness.

    DOI: 10.35848/1347-4065/ac79fe

    Web of Science

    Scopus

  25. Field emission current from protrusion structures formed by helium plasma with various impurity gases 査読有り

    Zhang R., Kajita S., Tanaka H., Hwangbo D., Ohno N.

    Proceedings - International Symposium on Discharges and Electrical Insulation in Vacuum, ISDEIV   2023-June 巻   頁: 529 - 532   2023年

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    出版者・発行元:Proceedings - International Symposium on Discharges and Electrical Insulation in Vacuum, ISDEIV  

    Rod-like protrusion structures were formed on tungsten by helium plasma exposure with various impurity gases seeded as nitrogen (N2) and argon (Ar). Surface morphology observations and field emission current measurements were done for two samples. Cross-section observation shows that the inside of the protrusions was solid but not porous like conventional fuzz. Therefore, a new formation mechanism which is different from fuzz can be considered. The field emission current from N2-seeded case was slightly higher than that from fuzz, but much lower than that from NTBs, while the field emission current from Ar-seeded case was similar to that from NTBs. The difference in field emission current could be due to the different morphology of the tips between two samples.

    DOI: 10.23919/ISDEIV55268.2023.10200357

    Scopus

  26. Thermal conductivity measurement of fuzzy W using a thermoreflectance method 査読有り

    Kajita S., Yagi T., Ohno N.

    Proceedings - International Symposium on Discharges and Electrical Insulation in Vacuum, ISDEIV   2023-June 巻   頁: 526 - 528   2023年

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    出版者・発行元:Proceedings - International Symposium on Discharges and Electrical Insulation in Vacuum, ISDEIV  

    Thermophysical properties of the fuzzy nanostructured tungsten (W) layer formed by helium plasma irradiation (a) are measured using a pulsed light heating thermoreflectance method. A three layered model has been developed to explain the temporal evolution of the themoreflectance signal. The thermal conductivity of the nanostructured layer was deduced to be in the range of 0.14-0.26% of the pure (ideal) W.

    DOI: 10.23919/ISDEIV55268.2023.10200254

    Scopus

  27. Use of machine learning for a helium line intensity ratio method in Magnum-PSI 査読有り 国際共著

    Kajita S., Iwai S., Tanaka H., Nishijima D., Fujii K., van der Meiden H., Ohno N.

    Nuclear Materials and Energy   33 巻   頁: 101281   2022年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    Optical emission spectroscopy (OES) of helium (He) line intensities has been used to measure the electron density, ne, and temperature, Te, in various plasma devices. In this study, a neural network with five hidden layers is introduced to model the relation between the OES data and ne/Te from laser Thomson scattering in the linear plasma device Magnum-PSI and compared to multiple regression analysis. It is shown that the neural network reduces the residual errors of prediction values (ne and Te) less than half those of the multiple regression analysis in the ranges of 2 × 1018<ne<8×1020 m−3 and 0.1<Te<4eV. We checked two different data splitting methods for training and validation data, i.e., with and without considering the unit of discharge. A comparison of the splitting methods suggests that the residual error will decrease to ∼10% even for a new discharge data when accumulating a sufficient data set.

    DOI: 10.1016/j.nme.2022.101281

    Web of Science

    Scopus

  28. Plasma induced surface nanostructure on semiconductors for the application of random laser 査読有り

    Shi Q., Fujiwara H., Osaka R., Kajita S., Yasuhara R., Ohno N., Uehara H.

    2022 Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2022 - Proceedings     2022年

     詳細を見る

    出版者・発行元:2022 Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2022 - Proceedings  

    Unique surface nanostructures were formed on semiconductors over a large area by Ar plasma irradiation with RF sample bias. As an application of these wavelength ordered size structure, we have demonstrated a random laser emission at UV region.

    DOI: 10.1109/CLEO-PR62338.2022.10432590

    Scopus

  29. POWER TRANSMISSION FACTOR FOR TUNGSTEN TARGET W/WO FIBER-FORM NANOSTRUCTURE IN H PLASMAS WITH HOT ELECTRON COMPONENT USING COMPACT PLASMA DEVICE AIT-PID 査読有り 国際誌

    Takamura, S; Miyamoto, T; Ohno, N

    FUSION SCIENCE AND TECHNOLOGY   63 巻 ( 1T ) 頁: 225 - 228   2013年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.13182/FST13-A16911

    Web of Science

  30. Simulation of dynamics of carbon dust particles in the JT-60U tokamak 査読有り 国際共著 国際誌

    Tanaka, Y; Smirnov, RD; Pigarov, AY; Takenaga, H; Asakura, N; Uesugi, Y; Ohno, N

    JOURNAL OF NUCLEAR MATERIALS   415 巻 ( 1 ) 頁: S1106 - S1110   2011年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2010.12.237

    Web of Science

  31. Dusty sheaths in plasmas with two-temperature electrons 査読有り 国際誌

    Asano, K; Chutov, YI; Kravchenko, OY; Ohno, N; Pshenychnyj, AF; Smirnov, RD; Takamura, S

    DUSTY PLASMAS IN THE NEW MILLENNIUM   649 巻   頁: 277 - 280   2002年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Web of Science

  32. Generation of high heat flux plasma in divertor plasma simulator by ion cyclotron wave heating 査読有り 国際誌

    Watanabe, S; Ohsawa, S; Takagi, M; Ohno, N; Uesugi, Y; Takamura, S

    ICPP 96 CONTRIBUTED PAPERS - PROCEEDINGS OF THE 1996 INTERNATIONAL CONFERENCE ON PLASMA PHYSICS, VOLS 1 AND 2     頁: 1050 - 1053   1997年

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

    Web of Science

  33. Generation of high heat flux plasmas by rf heating in divertor plasma simulator NAGDIS-II 査読有り 国際誌

    Watanabe, S; Ohsawa, S; Takagi, M; Ohno, N; Uesugi, Y; Takamura, S

    RADIO FREQUENCY POWER IN PLASMAS   ( 403 ) 頁: 483 - 486   1997年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Web of Science

  34. STUDIES ON SHEATH FORMATION IN DIVERTOR PLASMAS BY COMPUTER-SIMULATION USING PARTICLES 査読有り 国際誌

    OHNO, N; MASUZAKI, S; KONNO, H; TAKAMURA, S

    CONTRIBUTIONS TO PLASMA PHYSICS   32 巻 ( 3-4 ) 頁: 249 - 254   1992年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/ctpp.2150320312

    Web of Science

  35. イオンビーム・プラズマ系におけるサブハーモニクスの励起機構の研究 査読有り

    大野 哲靖, 粕谷 俊郎, 田中 雅慶, 小森 彰夫, 河合 良信

    九州大学大学院総合理工学報告   9 巻 ( 1 ) 頁: 23 - 27   1987年7月

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    記述言語:日本語   出版者・発行元:九州大学大学院総合理工学研究科  

    DOI: 10.15017/17680

    CiNii Research

  36. Recent progress of JT-60SA project toward plasma operation 査読有り 国際共著 国際誌

    Shirai H., Takahashi K., Di Pietro E., Abate D., Abdel Maksoud W., Abe H., Aiba N., Abe T., Akimitsu M., Ayllon-Guerola J., Arai T., Artaud J.F., Asakura N., Ashikawa N., Balbinot L., Barabaschi P., Baulaigue O., Belonohy E., Belpane A., Bin W., Bombarda F., Bolzonella T., Bonne F., Bonotto M., Botija J., Buermans J., Cabrera-Pérez S., Cardella A., Carralero D., Carraro L., Cavalier J., Cavinato M., Chernyshova M., Chiba S., Clement-Lorenzo S., Cocilovo V., Coda S., Coelho R., Coffey I., Collin B., Corato V., Cucchiaro A., Czarski T., Dairaku M., Davis S., Day C., Dela Luna E., De Tommasi G., Decool P., Di Pace L., Dibon M., Disset G., D’Lsa F., Ejiri A., Endo Y., Ezumi N., Falchetto G., Fassina A., Fejoz P., Ferro A., Fietz W., Figini L., Fornal T., Frello G., Fujita T., Fukuda T., Fukui K., Fukumoto M., Funaba H., Furukawa M., Futatani S., Gabellieri L., Gaio E., Galazka K., Garcia J., Garcia-Dominguez J., Garcia-Lopez J., Garcia-Munoz M., Garzotti L., Gasparini F., Gharafi S., Giacomelli L., Ginoulhiac G., Giruzzi G., Giudicotti L., Gonzalez-Martin J., Guillén-González R., Hajnal N., Hall S., Hamada K., Hanada K., Hanada M., Hasegawa K., Hatakeyama S., Hauer V., Hayashi N., Hayashi T., Heller R., Hidalgo-Salaverri J., Higashijima S.

    Nuclear Fusion   64 巻 ( 11 )   2024年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    Superconducting (SC) tokamak JT-60SA plays an essential role in fusion research and development by supporting and complementing the ITER project, providing directions to the DEMO design activity and fostering next generation scientists and engineers. Since the short circuit incident at the terminal joints of equilibrium field coil #1 during the integrated commissioning (IC) in March 2021, both EU and JA implementing agencies (IAs) have examined how to ensure safe operation of JT-60SA by mitigating the risk of possible discharge occurrence inside the cryostat. Based on the experience of the global Paschen tests, the IAs have established a strategy of risk mitigation measures, which is a combination of (i) reinforcement of insulation, (ii) avoiding unnecessary voltage application to the coil systems and (iii) immediate de-energization of the coils when deteriorated vacuum conditions are detected. Thanks to the considerable efforts of the Integrated Project Team members, the IC restarted in May 2023. After confirmation of the SC state of the coil systems (TF, EF and CS), the coil energization test and the plasma operation phase 1 (OP-1) started. The first plasma was successfully achieved on 23 October 2023 with a limited value of voltage and current applied to the coils. The plasma configuration control was also confirmed with low plasma current and low auxiliary heating power conditions. Based on the IO-F4E-QST collaboration, activities of JT-60SA have been shared with the IO and provided an important lesson for ITER assembly and commissioning, and will provide an outstanding contribution to fusion research at large. After OP-1, maintenance & enhancement phase 1 (M/E-1) starts from January 2024, in which in-vessel components are installed, and heating and diagnostic systems are extensively upgraded to allow a high power heating experiment planned in OP-2. In order to make the best use of JT-60SA, a newly organized JT-60SA experiment team will refine the research plan for the future high heating power operation phase.

    DOI: 10.1088/1741-4326/ad34e4

    Scopus

  37. Study of the intermittent plasma structure around the divertor simulation experimental module in GAMMA 10/PDX 招待有り 査読有り

    H.Tanaka, N.Ezumi, T.Sugiyama, H.Gamo, N.Shigematsu, M.Yoshikawa, J.Kohagura, M.Hirata, S.Togo N.Ohno, M.Sakamoto

    Physics of Plasmas   30 巻 ( 3 ) 頁: 10.1063/5.0129886   2023年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: DOI: 10.1063/5.0129886

  38. Increased Photoelectrochemical Performance of Vanadium Oxide Thin Film by Helium Plasma Treatment with Auxiliary Molybdenum Deposition 査読有り 国際共著

    Kajita Shin, Eda Tomoki, Feng Shuangyuan, Tanaka Hirohiko, Bieberle-Hutter Anja, Ohno Noriyasu

    ADVANCED ENERGY AND SUSTAINABILITY RESEARCH   4 巻   頁: 2200141   2023年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/aesr.202200141

    Web of Science

  39. Structural correlation of random lasing performance in plasma-induced surface-modified galium nitride 査読有り

    Q.Shi, H.Fujiwara, S.Kajita, R.Yasuhara H.Tanaka, N.Ohno,H.Uehara

    ACS Applied Optical Materials   1 巻   頁: 412 - 420   2022年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: doi.org/10.1021/acsaom.2c00085

  40. Corrigendum to “Photoelectrochemical properties of plasma-induced nanostructured tungsten oxide” [Appl. Surf. Sci. 580 (2022) 151979] (Applied Surface Science (2022) 580, (S0169433221030166), (10.1016/j.apsusc.2021.151979)) 招待有り 査読有り

    S.Feng, S.Kajita, M.Higashi, A.Bieberle-Hutter, T.Yoshida, N.Ohno

    Applied Surface Science   599 巻   頁: 153668   2022年10月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: DOI: 10.1016/j.apsusc.2022.153668

  41. Reduction of pulsed particle load with dynamic pressure induced by transient recycled neutral flux 査読有り 国際共著 国際誌

    Hayashi Y., Tanaka H., Ohno N., Kajita S., Morgan T., van der Meiden H., Scholten J., Vernimmen J., Natsume H., Sawada K., Masuda S.

    Plasma Physics and Controlled Fusion   64 巻 ( 10 ) 頁: 105013   2022年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma Physics and Controlled Fusion  

    From pulsed plasma experiments focusing on neutral pressure dependence, the impacts of a transition from a low to a high recycling target on the particle load were investigated and discussed in the linear plasma device, Magnum-PSI. Time traces of the target ion flux were mitigated in high neutral pressure cases because of a plasma-neutral interaction. On the other hand, in low neutral-pressure cases, the target ion flux indicated partial suppression in the last part of the pulse. The Langmuir probe, located 200 mm upstream from the target plate, did not exhibit such a suppression. Pulse suppression can be expected from the localized interaction between recycled neutral flux and pulsed plasma in front of the target. The mean-free paths of recycled neutral particles regarding the charge exchange with pulse ions and elastic scattering with background neutral particles were compared. Modeling using a fluid code coupled with a neutral transport code was performed, and it was concluded that dynamic pressure induced by the transient recycled neutral flux caused sufficient momentum loss to stagnate the pulsed plasma toward the target plate.

    DOI: 10.1088/1361-6587/ac8acb

    Scopus

  42. Bidirectional reflectance distribution function of recrystallized tungsten mono-block exposed to cyclic heat loading 査読有り 国際誌

    Natsume H., Nojiri K., Kajita S., Fukuda M., Ushiki T., Tanaka H., Sugie T., Kitazawa S.i., Kikuchi T., Yokozuka T., Ohno N., Ezato K., Hatae T.

    Nuclear Materials and Energy   33 巻   頁: 101243   2022年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    The bidirectional reflectance distribution function (BRDF) of recrystallized tungsten mono-blocks exposed to cyclic heat loading for ITER divertor outer vertical target was measured using a goniophotometer at a wavelength of 473 nm. Laser microscope observations revealed that the surface roughness of the mono-block increased by an order of magnitude after cyclic heat loads of approximately 20 MWm−2. Furthermore, the overall values of BRDF decreased with an increase in cyclic heat loading. A comparison between the modeled and measured BRDFs showed that an additional Lambertian component is necessary to a specular function (microfacet model or Gaussian function) to fit the measured BRDFs when the surface of the mono-blocks becomes rough.

    DOI: 10.1016/j.nme.2022.101243

    Scopus

  43. Fuzz Growth Process under He-W Co-Deposition Conditions 査読有り 国際共著 国際誌

    Shen W., Kajita S., Tanaka H., Shi Q., Ohno N.

    Plasma and Fusion Research   17 巻 ( 0 ) 頁: 1302094 - 1302094   2022年8月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    Helium (He)-Tungsten (W) co-deposition experiments were conducted in the linear plasma device Co-NAGDIS at a temperature of 1223K to observe the characteristics of fuzz growth on theWsurface with auxiliary W deposition. The dependence on the deposition rate of W was investigated and a clear difference in fuzz thickness was found between He-only and co-deposition experiments. In addition, the fuzz structures on a single sample exhibited a spatially nonuniform distribution, which was probably caused by the nonuniformity in the deposition rate.

    DOI: 10.1585/pfr.17.1302094

    Scopus

    CiNii Research

  44. Measurement of the Bidirectional Reflectance Distribution Function of Tungsten Surface Sputtered in Argon Plasma 査読有り

    H.Natsume, K.Nojiri, S.Kajita, T.Ushiki, T.Sugie, S.Kitazawa, T.Kikuchi, T.Yokozuka, H.Tanaka, N.Ohno, T.Hatae

    Plasma and Fusion Research:Regular Articles   17 巻   頁: 2405041   2022年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: DOI: 10.1585/pfr.17.2405041

  45. Isotope Effect for Plasma Detachment in Helium and Hydrogen/Deuterium Mixture Plasmas 査読有り 国際誌

    Guo X., Tanaka H., Kajita S., Ohno N., Hattori S., Sawada K.

    Plasma and Fusion Research   17 巻 ( 0 ) 頁: 2402027 - 2402027   2022年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    To investigate the isotope effect on the plasma detachment in helium (He) and hydrogen (H)/deuterium (D) mixture plasmas, we performed H2, D2 or He gas puffing into He plasma in the linear plasma device NAGDIS-II. Axial distributions of electron density (ne) and electron temperature (Te) were obtained using a movable Langmuir probe. Additionally, optical emission spectroscopy (OES) was applied to measure axial distributions of Balmer lines and He I lines. When the neutral gas pressure was high (ΔPn = 7~10 mTorr), ne distribution in He-D2 mixture plasma was similar to that in pure He plasma, showing a sharp decrease at the downstream region where Te < 1 eV. In contrast, in He-H2 mixture plasma, a decrease in ne was confirmed from upstream region where Te > 1 eV. The upstream Hα/Hγ in He-H2 plasma was significantly larger than the Dα/Dγ in He-D2 plasma at the same Te. This result indicated that molecular activated recombination (MAR) processes significantly occurred in He-H2 plasma, while electron-ion recombination (EIR) processes were dominant in He-D2 and pure He plasmas.

    DOI: 10.1585/pfr.17.2402027

    Scopus

    CiNii Research

  46. Study of optical emission spectroscopy in dual frequency synchronized pulsed capacitively coupled discharges with DC bias at low-pressure in Ar/O2/C4F8 plasma etching 査読有り 国際共著

    B.B,Sahu, K.Nakane, K.Ishikawa, M.Sekine, T.Tsutsumi, T.Gohira, Y.Ohya, N.Ohno, M.Hori

    Physical Chemistry Chemical Physics   24 巻   頁: 13883 - 13896   2022年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: doi.org/10.1039/D2CP00289B

  47. Changes in morphology and field emission property of nano-tendril bundles after high temperature annealing 査読有り 国際共著 国際誌

    Zhang R., Kajita S., Hwangbo D., Sinelnikov D., Tanaka H., Ohno N.

    Nuclear Materials and Energy   31 巻   頁: 101178   2022年4月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    Nano-tendril bundles (NTBs) are known to be formed on tungsten by helium plasma exposure with additional neon impurity gas. In this study, the annealing experiments were conducted at the sample temperature of 1473 – 1673 K to investigate the changes of morphology and field emission property of NTBs. With NTBs formed on a W surface, the surface did not fully recover to a smoothed surface and the NTBs remained the fiber-form structures after the annealing at 1673 K for one hour. In addition, the onset electric field for field emission increased, while the emission current from NTBs significantly decreased after the annealing. When the samples were biased at −250 V during helium plasma exposure, arc ignition was confirmed on W surface with NTBs, whereas no arc ignition appeared on W with annealed NTBs.

    DOI: 10.1016/j.nme.2022.101178

    Scopus

  48. An approach to implement a heat flux limit in a model for fusion relevant plasmas 査読有り 国際共著

    M.Z.Tokar, M.Kobayashi, N.Ohno

    Physics of Plasmas   29 巻   頁: 32502   2022年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/5.0079524

  49. Completion of JT-60SA construction and contribution to ITER 査読有り 国際共著 国際誌

    Kamada Y., Di Pietro E., Hanada M., Barabaschi P., Ide S., Davis S., Yoshida M., Giruzzi G., Sozzi C., Abdel Maksoud W., Abe H., Aiba N., Akiyama T., Ayllon-Guerola J., Arai T., Artaud J.F., Asakura N., Ashikawa N., Balbinot L., Bando T., Baulaigue O., Belonohy E., Bin W., Bombarda F., Bolzonella T., Bonne F., Bonotto M., Botija J., Cabrera-Pérez S., Cardella A., Carraro L., Cavalier J., Chernyshova M., Chiba S., Clement-Lorenzo S., Cocilovo V., Coda S., Coelho R., Coffey I., Collin B., Corato V., Cucchiaro A., Czarski T., Dairaku M., Davis S., Day C., de la Luna E., De Tommasi G., Decool P., Di Pace L., Di Pietro E., Dibon M., Disset G., Ejiri A., Endo Y., Ezumi N., Falchetto G., Fassina A., Fejoz P., Ferro A., Fietz W., Figini L., Fornal T., Frello G., Fujita T., Fukuda T., Fukui K., Fukumoto M., Furukawa M., Futatani S., Gabellieri L., Gaio E., Galazka K., Garcia J., Garcia-Dominguez J., Garcia-Lopez J., Garcia-Munoz M., Garzotti L., Gasparini F., Gharafi S., Giacomelli L., Ginoulhiac G., Giruzzi G., Giudicotti L., Guillén González R., Hajnal N., Hall S., Hamada K., Hanada K., Hanada M., Hasegawa K., Hatae T., Hatakeyama S., Hauer V., Hayashi N., Hayashi T., Heller R., Higashijima S., Hinata J.

    Nuclear Fusion   62 巻 ( 4 ) 頁: 42002   2022年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    Construction of the JT-60SA tokamak was completed on schedule in March 2020. Manufacture and assembly of all the main tokamak components satisfied technical requirements, including dimensional accuracy and functional performances. Development of the plasma heating systems and diagnostics have also progressed, including the demonstration of the favourable electron cyclotron range of frequency (ECRF) transmission at multiple frequencies and the achievement of long sustainment of a high-energy intense negative ion beam. Development of all the tokamak operation control systems has been completed, together with an improved plasma equilibrium control scheme suitable for superconducting tokamaks including ITER. For preparation of the tokamak operation, plasma discharge scenarios have been established using this advanced equilibrium controller. Individual commissioning of the cryogenic system and the power supply system confirmed that these systems satisfy design requirements including operational schemes contributing directly to ITER, such as active control of heat load fluctuation of the cryoplant, which is essential for dynamic operation in superconducting tokamaks. The integrated commissioning (IC) is started by vacuum pumping of the vacuum vessel and cryostat, and then moved to cool-down of the tokamak and coil excitation tests. Transition to the super-conducting state was confirmed for all the TF, EF and CS coils. The TF coil current successfully reached 25.7 kA, which is the nominal operating current of the TF coil. For this nominal toroidal field of 2.25 T, ECRF was applied and an ECRF plasma was created. The IC was, however, suspended by an incident of over current of one of the superconducting equilibrium field coil and He leakage caused by insufficient voltage holding capability at a terminal joint of the coil. The unique importance of JT-60SA for H-mode and high-β steady-state plasma research has been confirmed using advanced integrated modellings. These experiences of assembly, IC and plasma operation of JT-60SA contribute to ITER risk mitigation and efficient implementation of ITER operation.

    DOI: 10.1088/1741-4326/ac10e7

    Scopus

  50. Nitrogen Atom Density Measurements in NAGDIS-T Using Vacuum Ultraviolet Absorption Spectroscopy 査読有り

    Nishio Ryosuke, Kajita Shin, Tanaka Hirohiko, Asaoka Koji, Tsutsumi Takayoshi, Hori Masaru, Ohno Noriyasu

    PLASMA AND FUSION RESEARCH   17 巻 ( 0 ) 頁: 1201004 - 1201004   2022年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    DOI: 10.1585/pfr.17.1201004

    Web of Science

    CiNii Research

  51. Plasma induced surface nanostructure on semiconductors for the application of random laser 査読有り

    Shi Q., Fujiwara H., Osaka R., Kajita S., Yasuhara R., Ohno N., Uehara H.

    Optics InfoBase Conference Papers     2022年

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    出版者・発行元:Optics InfoBase Conference Papers  

    Unique surface nanostructures were formed on semiconductors over a large area by Ar plasma irradiation with RF sample bias. As an application of these wavelength ordered size structure, we have demonstrated a random laser emission at UV region.

    DOI: 10.1364/CLEOPR.2022.CFP8J_02

    Scopus

  52. Photoelectrochemical properties of plasma-induced nanostructured tungsten oxide 査読有り 国際共著 国際誌

    Feng S., Kajita S., Higashi M., Bieberle-Hütter A., Yoshida T., Ohno N.

    Applied Surface Science   580 巻   頁: 151979(7 pp)   2021年12月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Applied Surface Science  

    Helium (He)-induced nanostructured tungsten sheets were synthesized by He plasma irradiation under different plasma exposure durations. After calcination, nanostructured tungsten oxide samples were used as photoelectrodes to test photoelectrochemical (PEC) performance. The results showed that nanostructured WO3 photoanodes have higher PEC performance compared to the sample without nanostructures. The 15 min irradiated sample had the highest photocurrent density of 3.5 mA/cm2 under the thermodynamic potential of water oxidation (1.23 V vs. RHE). It was found that the oxide layer thickness and exposed crystal facet have a significant impact on PEC performance. The plasma synthesis technique has proved to be an effective method for preparing nanostructured WO3 photoelectrodes.

    DOI: 10.1016/j.apsusc.2021.151979

    Scopus

  53. Growth of Mo Large-Scale Fiberform Nanostructures 査読有り

    Kajita Shin, Okuyama Tatsuki, Tanaka Hirohiko, Ohno Noriyasu

    PLASMA AND FUSION RESEARCH   16 巻 ( 0 ) 頁: 1206105 - 1206105   2021年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    <p>We performed helium (He) plasma irradiation to molybdenum (Mo) substrate with auxiliary Mo deposition. Different from W cases, large-scale fiberform nanostructure (LFN) growth did not occur easily. The experiments suggested that the experimental condition of Mo LFN growth has a much narrower conditional window than that of fuzz growth or another hidden control factor exists for LFN growth.</p>

    DOI: 10.1585/pfr.16.1206105

    Web of Science

  54. Penetration of deuterium into neutron-irradiated tungsten under plasma exposure 査読有り

    Yajima M., Hatano Y., Alimov V.K., Toyama T., Kuwabara T., Schwarz-Selinger T., Oya Y., Spitsyn A.V., Ohno N.

    Physica Scripta   96 巻 ( 12 ) 頁: 124042   2021年10月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physica Scripta  

    Hydrogen isotope trapping at lattice defects in neutron-irradiated tungsten (W), a leading candidate as plasma facing material, is an important problem determining tritium (T) inventory in a vacuum vessel of a future fusion reactor. In this study, W samples were irradiated with neutrons in the Belgium Reactor 2 at 563 K to 0.06 or 0.016 displacement per atom (dpa). After characterizing defects by positron lifetime measurements, deuterium (D) penetration under exposure to D plasma was examined at 563-773 K. Positron lifetime showed the presence of dislocations, monovacancies and relatively large vacancy clusters. These defects trapped D atoms with different values of binding energy. Dependence of D retention on plasma exposure temperature and damage level indicated that the concentrations of weak traps with smaller binding energy increased more significantly with damage level than those of strong traps.

    DOI: 10.1088/1402-4896/ac2c20

    Scopus

    その他リンク: https://iopscience.iop.org/article/10.1088/1402-4896/ac2c20/pdf

  55. The dependence of Mo ratio on the formation of uniform black silicon by helium plasma irradiation 査読有り 国際共著

    Shi Quan, Kajita Shin, Feng Shuangyuan, Ohno Noriyasu

    JOURNAL OF PHYSICS D-APPLIED PHYSICS   54 巻 ( 40 ) 頁: 405202   2021年10月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Physics D: Applied Physics  

    Reducing the optical reflection of silicon (Si) material is a crucial issue on the surface of solar cells and other photonic applications. Fabrication of nanocone structures on the Si surface (black Si) by plasma (helium or argon) irradiation is a novel technique in recent decades with advantages, such as simple, economical, and harmless to the Si substrate. However, the uniformity and controllability of the surface remain problematic. In this study, uniform black silicon was obtained by low energy (<50 eV) helium ion irradiation with auxiliary Mo co-deposition. The characteristics of the nanocone show a clear relation with the Mo ratio. Deposited Mo was found to accumulate on the cone body, especially on the tip, and it worked as a nano mask to induce the formation of the nanocone and protect it from sputtering. The surface with high and large diameter nanocones possesses low reflectances of roughly 2%. The study of the relation between Mo ratio, characteristics of the nanostructure, and the reflectance of the surface raises a potential method of surface tailoring.

    DOI: 10.1088/1361-6463/ac1190

    Web of Science

    Scopus

  56. Enhanced photocatalytic ethylene decomposition with anatase-rutile mixed nanostructures formed by He plasma treatment 査読有り

    Kajita S., Miyaguchi K., Tanaka H., Yasunaga E., Yoshida T., Ohno N.

    Journal of Photochemistry and Photobiology A: Chemistry   418 巻   頁: 113420(8 pp)   2021年9月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Photochemistry and Photobiology A: Chemistry  

    In order to realize high-performance titanium dioxide (TiO2) photocatalysts for ethylene decomposition, titanium (Ti) thin film samples with fiberform nanostructures were prepared by helium (He) plasma treatment. Then, the oxidation condition for ethylene decomposition were optimized in terms of the oxidation temperature and duration. It is shown that He plasma irradiation with Ti deposition followed by oxidation in the air formed anatase-rich TiO2. The rutile anatase transition temperature increased to higher than 1000 K on the He treated samples and the best photocatalytic performance is twice higher than that on TiO2 sample formed in a magnetron sputtering device. Helium plasma treatment induces vacancies, He clusters, and He bubbles together with formation of nanostructures. The results suggested that those morphology changes lead to the formation of stable anatase structure, which is likely the key factor for the enhancement of photocatalytic activity. Based on the obtained ethylene decomposition rate, we will discuss the necessary light source and amount of photocatalysts to keep vegetables fresh in a long-distance transport cargo.

    DOI: 10.1016/j.jphotochem.2021.113420

    Scopus

  57. Thermal treatment of W large-scale fiberform nanostructures 査読有り

    Kajita Shin, Okuyama Tatsuki, Tanaka Hirohiko, Kuwabara Tatsuya, Ohno Noriyasu, Yoshida Naoaki

    PHYSICA SCRIPTA   96 巻 ( 9 )   2021年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physica Scripta  

    Recent experiments have revealed that accelerated tungsten (W) nanostructure growth occurs during the exposure to helium (He) plasmas with an additional W deposition, and mm-thick large-scale fiberform nanostructures (LFNs) are formed when certain condition is satisfied. In order to reveal whether accelerated growth occurs in fusion device, it is important to understand the annealing process in addition to the growth process. In this study, we will perform thermal treatment of W LFNs. Detailed observation reveals that the LFNs shrink at a faster rate than that of conventional fuzz, though it takes longer time to fully be reintegrated to the surface because the thickness is orders of magnitude greater.

    DOI: 10.1088/1402-4896/ac0866

    Web of Science

    Scopus

  58. Enhancement of Arc Ignition on Tungsten in Helium Plasmas with Impurity Gases 査読有り 国際共著

    ZHANG Rongshi, KAJITA Shin, HWANGBO Dogyun, TANAKA Hirohiko, OHNO Noriyasu

    Plasma and Fusion Research   16 巻 ( 0 ) 頁: 24045069(5 pp) - 2405069   2021年5月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    <p>Arcing was ignited on deformed tungsten (W) surfaces, where W <i>fuzz </i>and/or <i>nano-tendril bundles </i>(NTBs) were grown, by steady state helium (He) plasma exposures with impurity gas seeding. At the same sample potential of −250 V, the presence of NTBs enhanced the frequency of arc ignition, whereas no arc ignition appeared on typical fuzz surfaces without NTBs. After a series of arc ignitions on a sample surface with NTBs, the aspect ratio of NTBs decreased, indicating that protruded NTBs with larger aspect ratio tend to trigger arcing easily.</p>

    DOI: 10.1585/pfr.16.2405069

    Scopus

  59. Modeling of the impurity-induced silicon nanocone growth by low energy helium plasma irradiation 査読有り 国際共著

    Q Shi, S Kajita, S Dai, S Feng, N Ohno

    Plasma Science and Technology   23 巻 ( 4 ) 頁: 45503   2021年4月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma Science and Technology  

    DOI: 10.1088/2058-6272/abea71

    Scopus

  60. Influence of Nitrogen Ratio on Plasma Detachment during Combined Seeding with Hydrogen on Divertor Simulation Experiment of GAMMA 10/PDX 査読有り

    GAMO Hiroki, HWANGBO Dogyun, SAKAMOTO Mizuki, PERILLO Renato, KUWABARA Tatsuya, TANAKA Hirohiko, OHNO Noriyasu, SAWADA Keiji, TONEGAWA Akira, MASUZAKI Suguru, EZUMI Naomichi, SUGIYAMA Tsukasa, NOJIRI Kunpei, KONDO Ayane, HIRATA Mafumi, KOHAGURA Junko, YOSHIKAWA Masayuki, NAKASHIMA Yousuke

    Plasma and Fusion Research   16 巻 ( 0 ) 頁: 2402041 - 2402041   2021年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    <p>Influences of nitrogen ratio on plasma detachment and molecular activated recombination (MAR) processes during combined seeding with hydrogen have been investigated utilizing end-loss plasma in the GAMMA 10/PDX tandem mirror. Additional gases were injected under the condition that hydrogen partial pressure was fixed and nitrogen partial pressure was changed from 0% - 10% compared to that of hydrogen. Electron density and ion flux further decrease with increasing nitrogen ratio. In addition, it is suggested that the hydrogen-MAR process that begins with dissociative attachment is suppressed during combined seeding of nitrogen and hydrogen. Observed emission spectrum of NH radicals suggests that the density of NH increases as nitrogen ratio increases and nitrogen-induced MAR efficiently contributes to the reduction of particle flux.</p>

    DOI: 10.1585/pfr.16.2402041

    Scopus

  61. Computer Tomography on Divertor Impurity Monitor for ITER with Minimizing Errors in a Logarithmic Scale 招待有り 査読有り 国際共著

    NATSUME Hiroki, OGAWA Hiroaki, KITAZAWA Sin-iti, KAJITA Shin, NEVEROV Vladislav S., KHUSNUTDINOV Radmir I., VESHCHEV Evgeny, DE BOCK Maarten, POLEVOI Alexei R., TANAKA Hirohiko, OHNO Noriyasu

    Plasma and Fusion Research   16 巻 ( 0 ) 頁: 2405019 - 2405019   2021年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    <p>The computer tomography for divertor impurity monitor, which measures plasma emissions in the divertor region, for ITER has been conducted using a ray-tracing technique. We have attempted four different solution methods for the inversion problem and compared the results. The solution methods which minimize errors in logarithmic scale had better performance than the methods which minimize errors in linear scale. This is likely due to the fact that the values in the emission profile vary in a wide range of orders of magnitude. The accuracy of the reconstruction has been investigated by changing discharge conditions and the number of field-of-views used. The deterioration in accuracy was most noticeable when the emission profile was reconstructed using only two field-of-views. In addition, the accuracy deteriorated, making the estimation more challenging, under discharge conditions with low emission intensity because of the wider range of emission intensity under such conditions.</p>

    DOI: 10.1585/pfr.16.2405019

    Scopus

  62. Particle-in-cell-Monte Carlo collision simulation and experimental measurement of Ar plasma in a fast atom beam source for surface-activated bonding 査読有り 国際誌

    R.Morisaki, T.Yamazaki, C.Oka, J.Sakurai, T.Hirai, T.Takahashi, H.Tsuji, N.Ohno, S.Hata

    Japanese Journal of Applied Physics   60 巻 ( SC ) 頁: SCCB01   2021年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.35848/1347-4065/abe683

    Scopus

  63. Doppler and Stark Broadenings of He II Emission in NAGDIS-PG 招待有り 査読有り

    KAJITA Shin, NAKAMORI Takaya, TANAKA Hirohiko, KIKUCHI Yusuke, OHNO Noriyasu

    Plasma and Fusion Research   16 巻 ( 0 ) 頁: 1202013 - 1202013   2021年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:一般社団法人 プラズマ・核融合学会  

    <p>Time evolutions of the emission from helium (He) ion at 468.6 nm were observed in the magnetized co-axial plasma gun device NAGDIS-PG, and the broadening of the spectrum was analyzed in terms of Doppler and Stark broadenings to deduce the ion temperature and the electron density. A significant broadening of the He II spectrum was identified around a dip in the discharge current, suggesting that increases in the temperature and density occurred.</p>

    DOI: 10.1585/pfr.16.1202013

    Scopus

  64. Fabrication of nanostructured Ti thin film with Ti deposition in He plasmas 査読有り

    Miyaguchi Kazuya, Kajita Shin, Tanaka Hirohiko, Ohno Noriyasu

    JAPANESE JOURNAL OF APPLIED PHYSICS   60 巻 ( 3 ) 頁: 038004(4 pp)   2021年2月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.35848/1347-4065/abe3a5

    Web of Science

    Scopus

  65. Accelerated/reduced growth of tungsten fuzz by deposition of metals 査読有り 国際共著

    S. Kajita, T. Morgan, H. Tanaka, Y. Hayashi, N. Yoshida, D. Nagata, J. Vernimmen, S. Feng, R. Zhang, N. Ohno

    Journal of Nuclear Materials   548 巻   頁: 152844   2021年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2021.152844

    Scopus

  66. Tungsten Large-Scale Fiberform Nanostructures Retained under High Temperature Conditions 査読有り

    T.Okuyama, S.Kajita, N.Yoshida, H.Tanaka, T.Kuwabara, N.Ohno

    PLASMA AND FUSION RESEARCH   16 巻   頁: 1206001   2021年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.16.1206001

    Web of Science

    Scopus

  67. Experimental observations and modelling of radiation asymmetries during N<inf>2</inf> seeding in LHD 査読有り 国際共著

    B.J. Peterson, G.Kawamura, P.L. van de Giessen, K.Mukai, H.Tanaka, R.Sano, S.N. Pandya, S.Y. Dai, S. Masuzaki, T. Akiyama, M. Kobayashi, M. Goto, G. Motojima, R. Sakamoto, N. Ohno, T. Morisaki, J. Miyazawa, the LHD Experiment Group

    Nuclear Materials and Energy   26 巻   頁: 100848   2020年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.nme.2020.100848

    Scopus

  68. Experimental observations and modelling of radiation asymmetries during Ne and N2 seeding in LHD 招待有り 査読有り 国際共著

    B.J. Peterson, G. Kawamura, P.L. van de Giessen, K. Mukai, S. Borling, H. Tanaka, R. Sano, S. N. Pandya, S. Y. Dai, S. Masuzaki, T. Akiyama, M. Kobayashi, M. Goto, G. Motojima, R. Sakamoto, N. Ohno, T. Morisaki, J. Miyazawa and the LHD Experiment Group

    Nuclear Materials and Energy   26 巻   頁: 100848   2020年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: doi.org/10.1016/j.nme.2020.100848

  69. Unipolar arc plasmas on nanostructured tungsten surfaces under perpendicular magnetic field 査読有り 国際共著

    D.Hwangbo, D.Nishijima, S.Kajita, R.Doerner, N.Ohno

    PLASMA SOURCES SCIENCE & TECHNOLOGY   29 巻 ( 12 ) 頁: 125015   2020年12月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1361-6595/abc817

    Web of Science

    Scopus

  70. Dynamics of Hydrogen Isotope Absorption and Emission of Neutron-Irradiated Tungsten 査読有り 国際共著

    T.Toyama, M.Yajima, N.Ohno, T.Kuwabara, V.Kh.Alimov, Y.Hatano

    PLASMA AND FUSION RESEARCH   15 巻   頁: 150581(7 pp)   2020年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.15.1505081

    Web of Science

  71. Plasma Potential Measurement in Detached Plasmas by Emissive Probe Considering Space-Charge-Limited Effect 査読有り

    S.Hattori, H.Tanka, S.Kajita, N.Ohno

    PLASMA AND FUSION RESEARCH   15 巻   頁: 1301082(4 pp)   2020年11月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.15.1301082

    Web of Science

  72. Size distribution of nano-tendril bundles with various additional impurity gases 査読有り

    R. Zhang, D. Hwangbo, S. Kajita, H. Tanaka, N. Ohno

    NUCLEAR MATERIALS AND ENERGY   25 巻   頁: 100843   2020年11月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.nme.2020.100843

    Web of Science

    Scopus

  73. Tungsten fuzz: Deposition effects and influence to fusion devices 査読有り

    S Kajita, N Yoshida, N Ohno

    NUCLEAR MATERIALS AND ENERGY   25 巻   頁: 100828   2020年11月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.nme.2020.100828

    Web of Science

    Scopus

  74. Cross-field transport in detached helium plasmas in Magnum-PSI 査読有り 国際共著

    H.Tanaka, Y.Hayashi, S.Kajita, H.J. van der Meiden, M.Yoshikawa, J.W.M.Vernimmen, J.Scholten, I.Classen, T.W.Morgan, N.Ohno

    PLASMA PHYSICS AND CONTROLLED FUSION   62 巻 ( 11 ) 頁: 115021 (14pp)   2020年10月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1361-6587/abb88f

    Web of Science

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  75. Nano-tendril bundles behavior under plasma-relevant electric fields 査読有り

    V.V.Kulagin, D.N.Sinelnikov, D.G.Bulgadaryan, N.E.Efimov, V.A.Kurnaev, D.Hwangbo, N.Ohno, S.Kajita

    VACUUM   183 巻   頁: 109799   2020年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.vacuum.2020.109799

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  76. Evaluation of axial decay length of plasma pressure in detached plasma 査読有り

    H.Tanaka, N.Ohno, S.Kajita, H.Takano, S.Hattori, Y.Imaeda

    NUCLEAR MATERIALS AND ENERGY   25 巻   頁: 100812(5 pp)   2020年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.nme.2020.100812

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  77. Detached helium plasma simulation by a one-dimensional fluid code with detailed collisional-radiative model 査読有り

    H.Tanaka, I.Saeki, N.Ohno, S.Kajita, T.Ido, H. Natsume, A.Hatayama, K.Hoshino, K.Sawada, M.Goto

    PHYSICS OF PLASMAS   27 巻 ( 10 ) 頁: 102505   2020年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/5.0015912

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  78. Dust Formation from Arc Spots on Nanostructured Tungsten Surface 査読有り 国際共著

    M.Yajima, S.Kajita, N.Ohno, S.Masuzaki, N.Yoshida, D.U.B.Assems, T.W.Morgan, K.Bystrovc, H, van der Meiden

    PLASMA AND FUSION RESEARCH   15 巻   頁: 1205061(3 pp)   2020年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.15.1205061

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  79. Atomic nitrogen density measurements by actinometry method in the toroidal device NAGDIS-T 査読有り

    S.Kajita, K.Asaoka, H.Tanaka, R.Nishio, T.Tsutsumi, M.Hori, N.Ohno

    JAPANESE JOURNAL OF APPLIED PHYSICS   59 巻 ( 8 ) 頁: 086002(6 pp)   2020年8月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.35846/1347-4065/aba456

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  80. Effect of temperature and incident ion energy on nanostructure formation on silicon exposed to helium plasma 査読有り 国際共著

    M.Thompson, Q.Shi, S.Kajita, N.Ohno, C.Corr

    PLASMA PROCESSES AND POLYMERS   17 巻 ( 12 ) 頁: e2000126(7 pp)   2020年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/ppap.202000126

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  81. Thin film and noble metal loading effects on the photocatalytic reactivity of helium-plasma-induced nanostructured tungsten oxides 査読有り

    S.Feng, S.Kajita, T.Yoshida, N.Ohno, D.Nagata, M.Tokitani

    MATERIALS RESEARCH EXPRESS   7 巻   頁: 75007   2020年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/2053-1591/aba394

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  82. The influence of impurities on the formation of nanocone structures on silicon surface irradiated by low energy helium plasma 査読有り

    Q.Shi, S. Kajita, N. Ohno, M.Tokitani, D.Nagata, S. Feng

    JOURNAL OF APPLIED PHYSICS   128 巻 ( 2 ) 頁: 23301   2020年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/5.0010416

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  83. Helium-W co-deposition layer: TEM observation and D retention 査読有り

    S.Kajita, K.Asai, N.Ohno, H. Tanaka, N.Yoshida, D. Nagata, M. Yajima

    JOURNAL OF NUCLEAR MATERIALS   540 巻   頁: 152350   2020年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2020.152350

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  84. Spatiotemporal dynamics of cross-field ejection events in recombining detached plasma 査読有り

    H.Tanaka, S.Kajita, H.Natsume, I.Saeki, N.Ohno

    PLASMA PHYSICS AND CONTROLLED FUSION   62 巻 ( 7 ) 頁: 075011(10 pp)   2020年6月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1361-6587/ab8e19

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  85. Application of dynamic mode decomposition to rotating structures in detached linear plasmas 査読有り

    H.Natsume, H. Tanaka, S. Kajita, N.Ohno

    PHYSICS OF PLASMAS   27 巻 ( 4 ) 頁: 42301   2020年4月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.5134869

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  86. Modifications of WNOx films by keV D and H ions 査読有り

    N.Matsunami, N.Ohno, M. Tokitani, B. Tsuchiya, M. Sataka, S. Okayasu

    SURFACE & COATINGS TECHNOLOGY   394 巻   頁: 125798   2020年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.surfcoat.2020.125798

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  87. Inspection of Arc Trails Formed in Stellarator/Heliotron Devices W7-X and LHD 査読有り 国際共著

      15 巻   頁: 2402012   2020年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma and Fusion Research  

    DOI: 10.1585/pfr.15.2402012

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  88. Helium irradiation effects on the surface modification and recrystallization of tungsten 査読有り 国際共著

    Khan A, De Temmerman G, Kajita S, Greuner H, Balden M, Hunger K, Ohno N, Hwangbo D, Tomita Y, Tokitani M, Nagata D, Yajima M

    PHYSICA SCRIPTA   T171 巻 ( 1 ) 頁: 14050   2020年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1402-4896/ab52c6

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  89. Microstructure and Retention in He-W Co-Deposition Layer 査読有り

    K.Asai, N.Yoshida, N.Ohno, S.Kajita, H.Tanaka, M.Yajima, D.Nagata

    PLASMA AND FUSION RESEARCH   15 巻   頁: 1201004   2020年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.15.1201004

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  90. Growth of nano-fibers on HCP-metals by He plasma irradiation 査読有り

    S.Kajita, T.Nojima, Y.Yamamoto, N.Yoshida, T.Okuyama, T.Kuwabara, N.Ohno

    JAPANESE JOURNAL OF APPLIED PHYSICS   59 巻 ( SH ) 頁: SHHA03   2020年2月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.7567/1347-4065/ab5bbf

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  91. First EMC3-EIRENE modelling of JT-60SA edge plasmas with/without resonant magnetic perturbation field 査読有り 国際共著

    H.Tanaka, G.Kawamura, K.Hoshino, M.Kobayashi, G.Matsunaga, Y.Suzuki, T.Lunt, Y.Feng, N.Ohno

    CONTRIBUTIONS TO PLASMA PHYSICS   60 巻 ( 5-6 ) 頁: e201900114   2020年2月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/ctpp.201900114

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  92. Dynamics of the changes in the parameters of the arc plasma during the destruction of a helium-induced tungsten fuzz by arc pulses 査読有り 国際共著

    S. A.Barengolts , D.Hwangbo , S.Kajita , N.Ohno , V. P.Frolova , A. G.Nikolaev , E. M.Oks , D. L.Shmelev , M. M.Tsventoukh , G. Yu Yushkov

    NUCLEAR FUSION   60 巻 ( 4 ) 頁: 44001   2020年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1741-4326/ab73c3

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  93. Photocatalytic application of helium plasma induced nanostructured tungsten oxides 査読有り

    S.Feng, S.Kajita, Y.Tomita, T.Yoshida, N.Ohno

    JAPANESE JOURNAL OF APPLIED PHYSICS   59 巻 ( SA ) 頁: SAAB04(6 pp)   2019年11月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.7567/1347-4065/ab4601

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  94. Helium-plasma–induced straight nanofiber growth on HCP metals 査読有り

    S.Kajita, T.Nojima, T.Okuyama, Y.Yamamoto, N.Yoshida, N.Ohno

    Acta Materialia   181 巻   頁: 342 - 351   2019年10月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 Acta Materialia Inc. Low-energy helium (He) plasma irradiations were conducted on ruthenium (Ru) and rhenium (Re), which have hexagonal close packed (HCP) crystal structures. Growth of linear shaped fiberform nanostructures were identified on the surfaces of the both metals after the He plasma irradiation. We also conducted He plasma irradiation while Re particles were deposited on tungsten substrate; 3-mm-thick large scale fiberform nanostructures were grown on the surface. The crystal orientation was analyzed using diffraction patterns of Re and Ru nanofibers together with detailed transmission electron microscope observations. It was found that the growth of linear nanofibers has a preferential crystal orientation in the growth direction and it is always in the c-direction of the HCP crystals. Potential growth processes and mechanisms are proposed based on the experimental observations.

    DOI: 10.1016/j.actamat.2019.09.053

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  95. Field Emission From Nanostructured Tendril Bundles 査読有り 国際共著

    D.Sinelnikov, D.Bulgadaryan, D.Hwangbo, S.Kajita, V.Kumaev, N.Ohno

    IEEE TRANSACTIONS ON PLASMA SCIENCE   47 巻 ( 11 ) 頁: 5186 - 5190   2019年10月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1109/TPS.2019.2942725

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  96. Kinetics of deuterium penetration into neutron-irradiated tungsten under exposure to high flux deuterium plasma 査読有り

    M. Yajima, Y. Hatano, N. Ohno, T. Kuwabara, T. Toyama, M. Takagi, K. Suzuki

    Nuclear Materials and Energy   21 巻   頁: 100699   2019年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 The Authors The objective of this study is to investigate the effects of neutron (n) irradiation on hydrogen isotope transport in tungsten (W). W samples were irradiated with neutrons in a fission reactor and then exposed to high flux deuterium (D) plasma at 563 K in a linear plasma device. The fraction of D release increased with increasing exposure time. In addition, the D retention in n-irradiated W increased in proportion to the square root of the plasma exposure time. These observations were explained by increase in the penetration depth of D with filling up displacement damages acting as strong trapping sites.

    DOI: 10.1016/j.nme.2019.100699

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  97. Application of Ion Sensitive Probe to High Density Plasmas in Magnum-PSI 査読有り 国際共著

    Y.Hayashi, N.Ohno, H.van der Meiden, J.Scholten, S.Kajita, J.van der Berg, R.Perillo, J.Vernimmen, T.Moragan

    PLASMA AND FUSION RESEARCH   14 巻   頁: 1202135(3 pp)   2019年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.14.1202135

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  98. Spatial and temporal measurement of recombining detached plasmas by laser Thomson scattering 査読有り

    S. Kajita, H. Ohshima, H. Tanaka, M. Seki, H. Takano, N. Ohno

    PLASMA SOURCES SCIENCE & TECHNOLOGY   28 巻   頁: 105015 (9pp)   2019年7月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1361-6595/ab318d

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  99. Photocatalytic decomposition of ethylene using He plasma induced nano-TiO<inf>2</inf> 査読有り

    S.Kajita, Y.Tomita, E.Yasunaga, T.Yoshida, K.Miyaguchi, H.Tanaka, N.Ohno

    Japanese Journal of Applied Physics   58 巻   頁: 070903(4 pp)   2019年6月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 The Japan Society of Applied Physics. Ethylene decomposition via photocatalytic reaction using ultra-violet light was performed using an oxidized titanium (Ti) sheet and/or thin film samples fabricated by helium (He) plasmas treatments. We prepared nanostructured Ti samples formed by He plasma irradiation and additional thin film deposited samples using radio frequency magnetron sputtering. The samples prepared in this study had a slightly lower photocatalytic activity compared to the thin film deposited on tungsten nanostructure samples previously reported; the anatase formation was solely identified on Ti sheet samples and is hopeful for further improvement of photocatalytic activity of plasma treated titania.

    DOI: 10.7567/1347-4065/ab2830

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  100. Fabrication of a nanostructured TiO<inf>2</inf> photocatalyst using He plasma-irradiated tungsten and ethylene gas decomposition 査読有り

    Y.Tomita, S.Kajita, E.Yasunaga, T.Yoshida, N.Ohno, H.Tanaka

    Japanese Journal of Applied Physics   58 巻 ( SE ) 頁: SEEG01(6 pp)   2019年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 The Japan Society of Applied Physics. Decomposition of ethylene gas by a photocatalyst is an environmentally friendly and sustainable process. We fabricated titanium dioxide thin films deposited on nanostructured tungsten substrates formed by exposure to helium plasma and evaluated their photocatalytic performance. The nanostructures were maintained even after sputtering and annealing, and the proportion of tungsten inside the thin film increased with increasing oxidation temperature. The photocatalytic activity was improved due to formation of the nanostructure.

    DOI: 10.7567/1347-4065/ab09c8

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  101. Investigation of recombination front region in detached plasmas in a linear divertor plasma simulator 査読有り 国際共著

    N.Ohno, M.Seki, H.Ohshima, H.Tanaka, S.Kajita, Y.Hayashi, H.Natsume, H.Takano, I.Saeki, M.Yoshikawa, H.van der Meiden

    Nuclear Materials and Energy   19 巻   頁: 458 - 462   2019年5月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

    We have investigated detailed plasma structure around the recombination front region (RFR), where volume electron-ion recombination (EIR) strongly occurs in detached plasmas, by using two-dimensional (2D) movable probe system as well as laser Thomson scattering diagnostics. The 2D distribution of electron density, electron temperature, and plasma potential around the RFR, has been revealed for the first time. The spatial distribution of the particle loss rate due to EIR estimated from electron temperature and electron density profiles indicated that the three-dimensional structure of the RFR adopts a cone structure. Furthermore, in the peripheral region of the RFR, the radial profile of the electron density was widened locally with increasing cross-field transport caused by plasma fluctuation. From the heat transport analysis of electrons, it was found that the thermal relaxation process between electrons and ions is important for the cooling of electrons, and that the convection of electrons regulates electron heat transport near the RFR.

    DOI: 10.1016/j.nme.2019.03.010

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  102. Generation of Spiral Shape Nitrogen Recombining Plasma for Atomic Nitrogen Source 査読有り

    K. Asaoka, N. Ohno, Y. Hayashi, S. Kajita, and H. Tanaka

    Plasma and Fusion Research   14 巻   頁: 3401069(4 pp)   2019年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.14.3401069

  103. Characterization of He induced nanostructures using SEM image analysis 査読有り

    H.Tanaka, S.Kajita, N.Ohno

    Plasma and Fusion Research   14 巻 ( Specialissue2 ) 頁: 3402049(6 pp)   2019年4月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 The Japan Society of Plasma Science and Nuclear Fusion Research. Helium induced nanostructures on tungsten were characterized by applying basic statistical analysis techniques to scanning electron microscope (SEM) images. As the analysis targets, pinhole- and fuzz-dominant surfaces irradiated with different ion fluences were employed. Although two-dimensional Fourier analysis of the normalized brightness of SEM images clarified several characteristic features, their differences are small to distinguish the dominant nanostructures. On the other hand, probability density functions (PDFs) of the normalized brightness indicate that hole- and fuzz-dominant surfaces have long tail and Gaussian-like shape, respectively. By using several indexes with considering the black and white saturation, it was found that kurtosis and Kullback- Leibler divergence could provide reasonable judgement as the characterization index.

    DOI: 10.1585/pfr.14.3402049

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  104. Synergistic effect of nitrogen and hydrogen seeding gases on plasma detachment in the GAMMA 10/PDX tandem mirror 査読有り

    N.Ezumi, T.Iijima, M.Sakamoto, Y.Nakashima, M.Hirata, M.Ichimura, R.Ikezoe, T.Imai, T.Kariya, I.Katanuma, J.Kohagura, R.Minami, T.Numakura, M. Yoshikawa, S. Togo, MD S.Islam, MD M.Islam, K.Nojiri, A.Terakado, S.Jang, Y.Kinoshita, T.Mikami, S.Yamashita, T.Yoshimoto, T.Hara, A.Hatayama, K.Ichimura, S.Kado, S.Masuzaki, T.Nakano, N.Ohno, K. Sawada, H. Tanaka, A.Tonegawa and R.Perillo

    Nuclear Fusion   59 巻   頁: 060030   2019年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  105. Ignition and Behavior of Arc Spots on Helium Irradiated Tungsten under Fusion Relevant Condition 査読有り

    S.Kajita, D.Hwangbo, N.Ohno

    IEEE Transactions on Plasma Science   47 巻 ( 8 ) 頁: 3909 - 3916   2019年4月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 1973-2012 IEEE. In nuclear fusion reactors, unipolar arcing is a longstanding plasma surface interaction issue. In this paper, short summaries of morphology changes by helium plasma irradiation under fusion relevant conditions and ignition of arcing on the He irradiated surfaces are given. Helium plasma irradiation leads to surface morphology changes, and arcing can be ignited on the surface in response to pulsed heat load accompanied by plasma instabilities. Then, we focused on arcing ignited on large-scale fiberform nanostructures (LFNs) formed with deposition of metallic particles together with helium-ion irradiation. Dusts release from the arc spot and the amount of material erosion are discussed based on the experiments.

    DOI: 10.1109/TPS.2019.2908193

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  106. Analysis of indefinite divertor footprint with proper orthogonal decomposition in hydrogen/deuterium plasmas in LHD 査読有り

    H.Tanaka, S.Masuzaki, G.Kawamura, M.Kobayashi, Y.Suzuki, T.Morisaki, N.Ohno LHD Experimental Group

    Nuclear Materials and Energy   19 巻   頁: 378 - 383   2019年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.nme.2019.03.014

  107. Increased energy absorption into W due to the metal deposited layer from an ELM-like pulsed plasma 査読有り

    T.Nakamori, N.Ohno, H.Tanaka, S.Kajita, Y.Kikuchi, T.Akiyama

    Plasma and Fusion Research   14 巻   頁: 1401051(5 pp)   2019年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 The Japan Society of Plasma Science and Nuclear Fusion Research. It is important in divertor physics research to investigate thermal response process of beryllium deposited tungsten to high transient heat load such as ELMs. We investigated the heat load on aluminum-coated tungsten by comparing the measured back surface temperature and calculation results of the one-dimensional heat conduction equation. When the plasma power was low enough so that the evaporation did not occur sufficiently, the heat load on the aluminum-coated tungsten was higher than the virgin tungsten. It was caused by the reduction in the energy reflection coefficient due to the formation of aluminum layer. The results suggested that the beryllium deposited layer adversely affects the heat load on the divertor plate when the heat load was not high such as Grassy-ELM.

    DOI: 10.1585/pfr.14.1401051

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  108. Double-probe measurement in recombining plasma using NAGDIS-II 査読有り

    Y. Hayashi, H. Nishikata, N. Ohno, S. Kajita, H. Tanaka, H. Ohshima, M. Seki

    Contributions to Plasma Physics   59 巻 ( 7 ) 頁: e201800088   2019年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim We have studied the validity of the double-probe method in recombining plasmas. Electron temperature (Te) measured with a double probe was quantitatively evaluated by taking into account the influences of plasma potential fluctuation, plasma resistivity, and electron density fluctuation on the current–voltage characteristics. Differential potential fluctuation and plasma resistivity between two electrodes have a minor effect on Te especially when the inter-distance is small (typically 1 mm). Scattering of measured Te due to the density fluctuation was sufficiently suppressed by making the data acquisition time long (typically 4 s) and taking the average. There is a good agreement between Te measured with the optimized double-probe method and that with laser Thomson scattering diagnostics.

    DOI: 10.1002/ctpp.201800088

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  109. Development of Thomson scattering measurement system for Upstream plasmas in the NAGDIS-II device 査読有り

    H.Takano, H.Ohshima, S.Kajita, H.Tanaka, N.Ohno

    Plasma and Fusion Research   14 巻 ( Specialissue1 ) 頁: 2405031(4 pp)   2019年2月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 The Japan Society of Plasma Science and Nuclear Fusion Research. A new laser Thomson scattering (LTS) measurement system in the upstream region of the linear plasma device NAGDIS-II is established in addition to the recently introduced LTS in the downstream. Further, horizontal distributions of the electron temperature and electron density were compared with those obtained from the Langmuir probe, indicating plasma disturbance due to the insertion of the probe head. We discuss the variation of the electron energy distribution function at upstream and downstream in the recombining plasma.

    DOI: 10.1585/pfr.14.2405031

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  110. Growth of membrane nanostructures on W co-deposition layer 査読有り

    S. Kajita, N. Yoshida, S. Kawaguchi, H. Tanaka, N. Ohno, D. Nagata, M. Tokitani

    Nuclear Materials and Energy   18 巻   頁: 339 - 344   2019年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 The Authors Large-scale mm thick fiberform nanostructures are grown when materials are subjected to high flux helium ions with tungsten particles (ions and neutrals) precipitation. Observations of the large-scale fiberform nanostructures (LFNs) were conducted by scanning electron microscope (SEM) and transmission electron microscope (TEM) analyses. In particular, this study focuses on membrane nanostructures. Membranes that contain He bubbles were always observed when LFNs covered the surface. We discuss the growth process of the membrane structures based on detailed observations.

    DOI: 10.1016/j.nme.2019.02.004

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  111. Spatiotemporal Structure of Hα Emission from the Detached Plasma in GAMMA 10/PDX 査読有り

    H.Tanaka, M.Sakamoto, N.Ezumi, A.Terakado, K.Nojiri, T.Mikami, Y.Kinoshita, K.Kobayashi, M.Yoshikawa, J. Kohagura, N.Ohno

    Plasma and Fusion Research: Regular Articles   14 巻   頁: 2402036(5 pp)   2019年2月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.14.2402036

  112. Growth process of nano-tendril bundles with sputtered tungsten 査読有り

    D. Hwangbo, S. Kajita, H. Tanaka, and N. Ohno

    Nuclear Materials and Energy   18 巻   頁: 250 - 257   2019年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2019 The Authors Nano-tendril bundles (NTBs) were generated in DC He plasma with impurity gas-seeding (Ne and N 2 ) under sputtering-dominated conditions. NTB morphologies were characterized using the net erosion yield of samples. NTBs’ height and area were analyzed and ion fluence dependence was discussed. For both impurities, the number of NTBs increased steadily with increasing the fluence. It was revealed that NTB can be generated newly and continuously regardless of ion fluence. Surface observations suggested that micro-protrusions can evolve into NTBs. The effect of re-deposition of W was discussed based on SEM observations. Line-of-sight deposition seemed to play a key role of W feeder to enable NTBs to grow greater.

    DOI: 10.1016/j.nme.2019.01.008

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  113. Multipoint measurements employing a microwave interferometer and a Langmuir probe in the detached linear plasma 査読有り

    H. Natsume, H. Tanaka, S. Kajita, M. Yoshikawa, M. Seki, H. Ohshima, and N. Ohno

    AIP ADVANCES   9 巻   頁: 015016 (6pp)   2019年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.5081929

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  114. Influence of heavier impurity deposition on surface morphology development and sputtering behavior explored in multiple linear plasma devices 査読有り 国際共著

    D.Nishijima, A.Kreter, M.Baldwin, D.Borodin, A.Eksaeva, D.Hwangbo, S.Kajita, M.Miyamoto, N.Ohno, M.Patino, A.Psopieszczyk, M.Rasinski, T.Schlummer, A.Terra, R.P.Doerner

    NUCLEAR MATERIALS AND ENERGY   18 巻   頁: 67 - 71   2019年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.nme.2018.12.008

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  115. Spatiotemporal Structure of H alpha Emission from the Detached Plasma in GAMMA 10/PDX 査読有り

    H.Tanaka, M.Sakamoto, N.Ezumi, A.Terakado, K.Nojiri, T.Mikami, Y.Kinoshita, K.Kobayashi, M.Yoshikawa, J. Kohagura, N.Ohno

    PLASMA AND FUSION RESEARCH   14 巻 ( Specialissue1 ) 頁: 2402036(5 pp)   2019年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.14.2402036

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  116. Effect of Damage Introduction and He Existence on D Retention in Tungsten by High Flux D Plasma Exposure 査読有り

    Yasuhisa Oya, Keisuke Azuma, Akihiro Togari, Moeko Nakata, Qilai Zhou, Mingzhong Zhao, Tatsuya Kuwabara, Noriyasu Ohno, Miyuki Yajima, Yuji Hatano, Takeshi Toyama

    Lecture Notes in Networks and Systems   53 巻 ( 8 ) 頁: 89 - 96   2019年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1007/978-3-319-99834-3_12

  117. Proton scattering from tungsten fuzz

    D. Bulgadaryan, D. Sinelnikov, V. Kurnaev, S. Kajita, D. Hwangbo, N. Ohno

    Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms   434 巻   頁: 9 - 12   2018年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms  

    © 2018 Elsevier B.V. Tungsten fuzz is a nanostructure formed on tungsten surface under helium plasma impact. In this work, we investigate this structure using the scattering of keV-energy protons. Energy spectra of scattered protons have double-peak shape that corresponds to the scattering from fuzz and underlying pure tungsten. The energy losses of protons in fuzz are estimated as the difference between primary beam energy and the energy corresponding to the local minimum between two peaks. Computer simulations with SRIM code also demonstrate double-peak shape of energy spectra of protons scattered from fuzzy target. Fuzz and pure tungsten stopping powers for protons are compared and fuzz density relative to pure tungsten is estimated and discussed. Evolution of H+energy spectra during fuzz irradiation by Ar+beam is measured and discussed.

    DOI: 10.1016/j.nimb.2018.07.038

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  118. Plasma exhaust and divertor studies in Japan and Europe broader approach, DEMO design activity 査読有り 国際共著

    N.Asakura, K.Hoshino , H.Utoh, Y.Someya, S.Suzuki, C.Bachmann, H.Reimerdes, R.Wenninger, H.Kudo, S.Tokunaga, Y.Hommai, Y.Sakamoto, R.Hiwatari, K.Tobita, Jeong-Ha You, G.Federici, K.Ezato, Y.Seki, ...N.Ohno

    Fusion Engineering and Design   136 巻   頁: 1214 - 1220   2018年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Fusion Engineering and Design  

    DOI: 10.1016/j.fusengdes.2018.04.104

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  119. Characterized divertor footprint profile modification with the edge pressure gradient in the Large Helical Device 査読有り

    Tanaka H., Masuzaki S., Kawamura G., Kobayashi M., Suzuki Y., Motojima G., Murase T., Morisaki T., Ohno N.

    Plasma Physics and Controlled Fusion   60 巻 ( 12 ) 頁: 125001   2018年10月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma Physics and Controlled Fusion  

    DOI: 10.1088/1361-6587/aae2d7

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  120. Morphologies of co-depositing W layer formed during He plasma irradiation 査読有り

    Kajita Shin, Kawaguchi Shota, Yoshida Naoaki, Ohno Noriyasu, Tanaka Hirohiko

    NUCLEAR FUSION   58 巻 ( 10 ) 頁: 106002   2018年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    DOI: 10.1088/1741-4326/aad24e

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  121. One-Step Plasma Synthesis of Nb<inf>2</inf>O<inf>5</inf> Nanofibers and their Enhanced Photocatalytic activity 査読有り

    S.Kajita, F.Mimuro, T.Yoshida, N.Ohno, N.Yoshida

    ChemPhysChem   19 巻 ( 23 ) 頁: 3237 - 3246   2018年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2018 Wiley-VCH Verlag GmbH &amp; Co. KGaA, Weinheim Fiberform nanostructured niobium (Nb) was fabricated by one step helium (He) plasma irradiation. He ion implantation formed He nano-bubbles on a Nb plate and led to formation of protrusions while migrating in Nb matrix; fiberform nanostructures (FN) were grown when the fluence became high (&gt;1026 m−2). The necessary conditions for the formation of Nb FN were revealed to be the surface temperature range of 900–1100 K and the incident ion energy higher than 70 eV. The sample was oxidized at 573–773 K in an air atmosphere, and Pt nanoparticles were photo-deposited on the Nb2O5 samples. The surface was analyzed by scanning electron microscope, transmission electron microscope, x-ray photoelectron spectroscopy, and ultraviolet-visible spectrophotometry. Photocatalytic activity of the fabricated materials was studied using methylene blue (MB) decolorization process. An enhanced photocatalytic performance was identified on FN Nb2O5 substrate with Pt deposition.

    DOI: 10.1002/cphc.201800769

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  122. Growth of nano-tendril bundles on tungsten with impurity-rich He plasmas 査読有り

    Hwangbo Dogyun, Kajita Shin, Ohno Noriyasu, McCarthy Patrick, Bradley James W, Tanaka Hirohiko

    NUCLEAR FUSION   58 巻 ( 9 ) 頁: 096022   2018年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    DOI: 10.1088/1741-4326/aacd1f

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  123. Thomson Scattering Measurement of Two Electron Temperature Components in Transition to Detached Plasmas 査読有り

    Ohshima Hiroshi, Kajita Shin, Tanaka Hirohiko, Ohno Noriyasu, Van der Meiden Hennie J

    PLASMA AND FUSION RESEARCH   13 巻   頁: 1201099   2018年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma and Fusion Research  

    DOI: 10.1585/pfr.13.1201099

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  124. Effect of the Nanostructured Layer Thickness on the Dynamics of Cathode Spots on Tungsten 査読有り 国際共著

    Sergey A. Barengolts, Vadim G. Mesyats, Mikhail M. Tsventoukh, Shin Kajita, Dogyun Hwangbo, Noriyasu Ohno

    IEEE Transactions on Plasma Science   46 巻 ( 11 ) 頁: 4044 - 4050   2018年8月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Transactions on Plasma Science  

    IEEE Experimental data on the effect of the thickness of a nanostructured layer present on the surface of a tungsten cathode on its arcing properties have been analyzed. It has been shown that if the nanostructured layer is not completely destroyed as a result of the operation of a cathode spot cell, the spot ``sinks&#039;&#039; in the layer, the spot cells group together, and the trajectory of the spot motion becomes ``entangled.&#039;&#039; To interpret the experimental results, the grouping of arc spot cells was simulated using a random walk model based on the Monte Carlo method into which an attractive force was introduced and assuming that the cell plasma density, i.e., the cell initiation probability, is proportional to 1/r&amp;#x00B2;, where r is the distance between two spot cells. It has been demonstrated that spot cells are entangled, forming a group and moving together when the attractive force between them is strong enough. When this force decreases and the directionality of the cells increases as the cathode spot shifts to a lower thickness region of the nanostructured layer, the velocity of motion of the spot increases and its trace left on the surface becomes narrower.

    DOI: 10.1109/TPS.2018.2859953

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  125. Blob- and hole-like structures outstanding during the transition from attached to detached divertor states in GAMMA 10/PDX 査読有り

    Tanaka, H, Sakamoto, M, Ezumi, N, Nojiri, K, Terakado, A, Mikami, T, Kinoshita, Y, Kobayashi, K, Yoshikawa, M, Kohagura, J, Ohno, N

    PHYSICS OF PLASMAS   25 巻 ( 8 ) 頁: 082505(6 pp)   2018年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER INST PHYSICS  

    DOI: 10.1063/1.5040800

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  126. Localized spiraling plasma ejection contributing the ion-flux broadening in the detached linear plasma 査読有り

    Tanaka, H, Takeyama, K, Yoshikawa, M, Kajita, S, Ohno, N, Hayashi, Y

    PLASMA PHYSICS AND CONTROLLED FUSION   60 巻 ( 7 ) 頁: 075013   2018年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

    DOI: 10.1088/1361-6587/aac0d8

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  127. Ignition and erosion of materials by arcing in fusion-relevant conditions 査読有り

    Hwangbo Dogyun, Kajita Shin, Barengolts Sergey A, Tsventoukh Mikhail M, Kawaguchi Shota, Mesyats Vadim G, Ohno Noriyasu

    CONTRIBUTIONS TO PLASMA PHYSICS   58 巻 ( 6-8 ) 頁: 608 - 615   2018年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Contributions to Plasma Physics  

    DOI: 10.1002/ctpp.201700157

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  128. Helium line emission spectroscopy in recombining detached plasmas 査読有り

    Shin Kajita, Kensuke Suzuki, Hirohiko Tanaka, Noriyasu Ohno

    Physics of Plasmas   25 巻 ( 6 ) 頁: 063303   2018年6月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physics of Plasmas  

    DOI: 10.1063/1.5029414

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  129. Nanostructure Growth on Rhodium/Ruthenium by the Exposure to He Plasma 査読有り

    Tomohiro NOJIMA, Shin KAJITA, Naoaki YOSHIDA, Shota KAWAGUCHI, Noriyasu OHNO, Hirohiko TANAKA, Masayuki TOKITANI, Daisuke NAGATA, Tsuyoshi AKIYAMA, Takashi YAGI

    Plasma and Fusion Research   13 巻   頁: 3406064   2018年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma and Fusion Research  

    DOI: 10.1585/pfr.13.3406065

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  130. Mode Structure Analysis of Detached Plasmas with 2D Images 査読有り

    Kajita Shin, Tanaka Hirohiko, Ohno Noriyasu, Onda Takuya

    PLASMA AND FUSION RESEARCH   13 巻   頁: 1402033(5 pp)   2018年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma and Fusion Research  

    DOI: 10.1585/pfr.13.1402033

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  131. Fabrication of photocatalytically active vanadium oxide nanostructures via plasma route 査読有り

    Shin Kajita, Tomoko Yoshida, Noriyasu Ohno, Yusuke Ichino, Naoaki Yoshida

    Journal of Physics D: Applied Physics   51 巻 ( 21 ) 頁: 215201   2018年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Physics D: Applied Physics  

    DOI: 10.1088/1361-6463/aabe44

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  132. Fuzzy nanostructure growth on precious metals by He plasma irradiation 査読有り

    Shin Kajita, Tomohiro Nojima, Yudai Tomita, Noriyasu Ohno, Hirohiko Tanaka, Naoaki Yoshida, Miyuki Yajima, Tsuyoshi Akiyama, Masayuki Tokitani, Takashi Yagi

    Surface and Coatings Technology   340 巻   頁: 86 - 92   2018年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Surface and Coatings Technology  

    DOI: 10.1016/j.surfcoat.2018.02.026

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  133. Pulsation Effects of Incident Ion Energy on W Fuzz Growth 査読有り

    Kajita Shin, Kawaguchi Shota, Hwangbo Dogyun, Tanaka Hirohiko, Ohno Noriyasu

    PLASMA AND FUSION RESEARCH   13 巻   頁: 1205001   2018年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma and Fusion Research  

    DOI: 10.1585/pfr.13.1205001

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  134. Measurement of He neutral temperature in detached plasmas using laser absorption spectroscopy 査読有り

    Aramaki M., Tsujihara T., Kajit S., Tanaka H., Ohno N.

    AIP Advances   8 巻 ( 1 ) 頁: 015308   2018年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AIP Advances  

    DOI: 10.1063/1.4997840

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  135. Analysis of ELM stability with extended MHD models in JET, JT-60U and future JT-60SA tokamak plasmas 査読有り

    Aiba N., Pamela S., Honda M., Urano H., Giroud C., Delabie E., Frassinetti L., Lupelli I., Hayashi N., Huijsmans G.T.A., Litaudon X., Abduallev S., Abhangi M., Abreu P., Afzal M., Aggarwal K.M., Ahlgren T., Ahn J.H., Aho-Mantila L., Airila M., Albanese R., Aldred V., Alegre D., Alessi E., Aleynikov P., Alfier A., Alkseev A., Allinson M., Alper B., Alves E., Ambrosino G., Ambrosino R., Amicucci L., Amosov V., Sundén E.A., Angelone M., Anghel M., Angioni C., Appel L., Appelbee C., Arena P., Ariola M., Arnichand H., Arshad S., Ash A., Ashikawa N., Aslanyan V., Asunta O., Auriemma F., Austin Y., Avotina L., Axton M.D., Ayres C., Bacharis M., Baciero A., Baião D., Bailey S., Baker A., Balboa I., Balden M., Balshaw N., Bament R., Banks J.W., Baranov Y.F., Barnard M.A., Barnes D., Barnes M., Barnsley R., Wiechec A.B., Orte L.B., Baruzzo M., Basiuk V., Bassan M., Bastow R., Batista A., Batistoni P., Baughan R., Bauvir B., Baylor L., Bazylev B., Beal J., Beaumont P.S., Beckers M., Beckett B., Becoulet A., Bekris N., Beldishevski M., Bell K., Belli F., Bellinger M., Belonohy , Ayed N.B., Benterman N.A., Bergsåker H., Bernardo J., Bernert M., Berry M., Bertalot L., Besliu C., Beurskens M.

    Plasma Physics and Controlled Fusion   60 巻 ( 1 )   2018年1月

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    記述言語:日本語   出版者・発行元:Plasma Physics and Controlled Fusion  

    The stability with respect to a peelingballooning mode (PBM) was investigated numerically with extended MHD simulation codes in JET, JT-60U and future JT-60SA plasmas. The MINERVA-DI code was used to analyze the linear stability, including the effects of rotation and ion diamagnetic drift (w∗i), in JET-ILW and JT-60SA plasmas, and the JOREK code was used to simulate nonlinear dynamics with rotation, viscosity and resistivity in JT-60U plasmas. It was validated quantitatively that the ELM trigger condition in JET-ILW plasmas can be reasonably explained by taking into account both the rotation and w∗i effects in the numerical analysis. When deuterium poloidal rotation is evaluated based on neoclassical theory, an increase in the effective charge of plasma destabilizes the PBM because of an acceleration of rotation and a decrease in w∗i. The difference in the amount of ELM energy loss in JT-60U plasmas rotating in opposite directions was reproduced qualitatively with JOREK. By comparing the ELM affected areas with linear eigenfunctions, it was confirmed that the difference in the linear stability property, due not to the rotation direction but to the plasma density profile, is thought to be responsible for changing the ELM energy loss just after the ELM crash. A predictive study to determine the pedestal profiles in JT-60SA was performed by updating the EPED1 model to include the rotation and w∗i effects in the PBM stability analysis. It was shown that the plasma rotation predicted with the neoclassical toroidal viscosity degrades the pedestal performance by about 10% by destabilizing the PBM, but the pressure pedestal height will be high enough to achieve the target parameters required for the ITER-like shape inductive scenario in JT-60SA.

    DOI: 10.1088/1361-6587/aa8bec

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  136. Enhanced growth of large-scale nanostructures with metallic ion precipitation in helium plasmas 査読有り

    Shin Kajita, Shota Kawaguchi, Noriyasu Ohno, Naoaki Yoshida

    Scientific Reports   8 巻   頁: 56   2018年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nature Publishing Group  

    Helium plasma irradiation on metal surfaces leads to the formation of metallic fuzzy nanostructures accompanied by the growth of helium bubbles in metals. The mechanism of the growth process, its impact for fusion devices, and potential application have been explored. Here we show enhanced growth of large-scale fuzz by precipitating additional metallic particles during helium plasma irradiation. The growth rate of the fuzzy structures became orders of magnitude greater than conventional fuzz growth
    in an hour of irradiation, 1 mm-thick visible tungsten and molybdenum fuzzy fur structures covered a tungsten metal substrate. Additional precipitation of metallic ions breaks the bottleneck diffusion process
    moreover, further acceleration in the growth rate could have occurred if the electric sheath shape was influenced by the grown structure and the electric field that formed around the structure started collecting ions.

    DOI: 10.1038/s41598-017-18476-7

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  137. Morphology Changes of Platinum and Tungsten Carbide by He Plasma Irradiation 査読有り

    Tomita Yudai, Kajita Shin, Ohno Noriyasu, Tanaka Hirohiko, Ichino Yusuke

    PLASMA AND FUSION RESEARCH   13 巻   頁: 3406074   2018年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma and Fusion Research  

    DOI: 10.1585/pfr.13.3406074

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  138. Recent progress of divertor simulation research using the GAMMA 10/PDX tandem mirror 査読有り

    Nakashima Y, Ichimura K, Islam M. S, Sakamoto M, Ezumi N, Hirata M, Ichimura M, Ikezoe R, Imai T, Kariya T, Katanuma I, Kohagura J, Minami R, Numakura T, Yoshikawa M, Iijima T, Islam M. M, Nojiri K, Shimizu K, Terakado A, Togo S, Asakura N, Fukumoto M, Hatayama A, Hirooka Y, Kado S, Kubo H, Masuzaki S, Matsuura H, Nakano T, Nagata S, Nishino N, Ohno N, Sagara A, Sawada K, Shoji M, Tonegawa A, Ueda Y

    NUCLEAR FUSION   57 巻 ( 11 )   2017年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    This paper describes the recent progress in divertor simulation research using the GAMMA 10/PDX tandem mirror towards the development of divertors in fusion reactors. During a plasma flow generation experiment in the end cell of the GAMMA 10/PDX, ICRF heating in the anchor cell successfully extended the particle flux up to 3.3 1023 m2 s-1. Superimposing the short pulse of the ECH also attained a maximum heat flux of ∼30 MW m-2. We have succeeded in achieving and characterizing the detachment of the high-temperature plasma, which is equivalent to the SOL plasma of tokamaks, by using the divertor simulation experimental module (D-module) in the GAMMA 10/PDX end cell, in spite of using a linear device with a short magnetic field line connection length. Various gases (Ar, Xe, Ne and N2) are examined to evaluate the effect of radiation cooling against the plasma flow at the MW m-2 level in the divertor simulation region and the following results are obtained: (i) Xe gas was most effective in the reduction of heat and particle fluxes (1%, 3%, respectively) and has a stronger effect on electron cooling (down to ∼1.6 eV) in the used gas species. (ii) Ne gas was less effective. On the other hand, (iii) N2 gas showed more favorable effects than Ar in the lower pressure range. These results will contribute to the progress in detached plasma operation and in clarifying the radiation cooling mechanism towards the development of future divertors.

    DOI: 10.1088/1741-4326/aa7cb4

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  139. Development of a Compact Divertor Plasma Simulator for Plasma-Wall Interaction Studies on Neutron-Irradiated Materials 査読有り

    N.Ohno, T.Kuwabara, M.Takagi, R.Nishimura, M.Yajima, A.Sagara, T.Toyama, K.Suzuki, H.Kurishita, T.Shikama, Y.Hatano, N.Yoshida

    PLASMA AND FUSION RESEARCH   12 巻 ( 0 ) 頁: 1405040 - 1405040   2017年10月

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    担当区分:筆頭著者   記述言語:日本語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    <p>We have developed a compact divertor plasma simulator (CDPS) that can produce steady-state deuterium and/or helium plasmas with densities above ∼ 10<sup>18 </sup>m<sup>−3 </sup>for Plasma-Wall Interaction (PWI) studies of neutronirradiated materials. The maximum particle flux is about 10<sup>22 </sup>m<sup>−2</sup>s<sup>−1</sup>. The CDPS was installed and is being operated in the radiation-controlled area of the International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University. We are able to control sample temperature within uncertainty of 5<sup>◦</sup>C during plasma exposure by adjusting the cooling air flow rate to the sample holder. The CDPS has a sample-carrier system, which makes it possible to transfer a plasma-irradiated sample from the sample holder to an infrared heater for analysis using thermal desorption spectroscopy (TDS) without exposing it to the air. This avoids the oxidation of the sample and minimizes the time between the end of plasma exposure and TDS analysis. An ITER-like tungsten (W) sample (A.L.M.T. Corp.), which has been irradiated by neutrons to 0.06 dpa in a fission reactor, was exposed to a deuterium plasma in the CDPS. The experimental results clearly show that the total deuterium retention in the neutron-irradiated W sample increases significantly in comparison with a pristine W, as demonstrated by broadening of the TDS spectrum at high temperatures.</p>

    DOI: 10.1585/pfr.12.1405040

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  140. Studies of power exhaust and divertor design for a 1.5 GW-level fusion power DEMO 査読有り

    N.Asakura, K.Hoshino, S.Suzuki, S.Tokunaga, Y.Someya, H.Utoh, H.Kudo, Y.Sakamoto, R.Hiwatari, K.Tobita, K.Shimizu, K.Ezato, Y.Seki, N.Ohno, Y.Ueda, Joint Special Team for DEMO Design

    Nuclear Fusion   57 巻   頁: 126050(12 pp)   2017年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1741-4326/aa867a

  141. Plasma Exhaust and Divertor Studies in JA and EU Broader Tokamak Fusion Reactor Approach, DEMO Design Activity 査読有り

    Nobuyuki Asakura, Kazuo Hoshino, Hiroyasu Utoh, Yoji Someya, Satoshi Suzuki, Christian Bachmann, Holger Reimerdes, Hironobu Kudo, Shinsuke Tokunaga, Yuki Homma, Yoshiteru Sakamoto, Ryoji Hiwatari, Ronald Wenninger, Kenji Tobita, Noriyasu Ohno,Gianfranco Federici, Koichiro Ezato, Yohji Seki, Noriyasu Ohno, Yoshio Ueda

        2017年9月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

  142. Extension of the operational regime of the LHD towards a deuterium experiment 査読有り

    Takeiri Y., Morisaki T., Osakabe M., Yokoyama M., Sakakibara S., Takahashi H., Nakamura Y., Oishi T., Motojima G., Murakami S., Ito K., Ejiri A., Imagawa S., Inagaki S., Isobe M., Kubo S., Masamune S., Mito T., Murakami I., Nagaoka K., Nagasaki K., Nishimura K., Sakamoto M., Sakamoto R., Shimozuma T., Shinohara K., Sugama H., Watanabe K. Y., Ahn J. W., Akata N., Akiyama T., Ashikawa N., Baldzuhn J., Bando T., Bernard E., Castejon F., Chikaraishi H., Emoto M., Evans T., Ezumi N., Fujii K., Funaba H., Goto M., Goto T., Gradic D., Gunsu Y., Hamaguchi S., Hasegawa H., Hayashi Y., Hidalgo C., Higashiguchi T., Hirooka Y., Hishinuma Y., Horiuchi R., Ichiguchi K., Ida K., Ido T., Igami H., Ikeda K., Ishiguro S., Ishizaki R., Ishizawa A., Ito A., Ito Y., Iwamoto A., Kamio S., Kamiya K., Kaneko O., Kanno R., Kasahara H., Kato D., Kato T., Kawahata K., Kawamura G., Kisaki M., Kitajima S., Ko W. H., Kobayashi M., Kobayashi S., Kobayashi T., Koga K., Kohyama A., Kumazawa R., Lee J. H., Lopez-Bruna D., Makino R., Masuzaki S., Matsumoto Y., Matsuura H., Mitarai O., Miura H., Miyazawa J., Mizuguchi N., Moon C., Morita S., Moritaka T., Mukai K., Muroga T., Muto S., Mutoh T., Nagasaka T., Nagayama Y., Nakajima N., Nakamura Y., Nakanishi H., Nakano H., Nakata M., Narushima Y., Nishijima D., Nishimura A., Nishimura S., Nishitani T., Nishiura M., Nobuta Y., Noto H., Nunami M., Obana T., Ogawa K., Ohdachi S., Ohno M., Ohno N., Ohtani H., Okamoto M., Oya Y., Ozaki T., Peterson B. J., Preynas M., Sagara S., Saito K., Sakaue H., Sanpei A., Satake S., Sato M., Saze T., Schmitz O., Seki R., Seki T., Sharov I., Shimizu A., Shiratani M., Shoji M., Skinner C., Soga R., Stange T., Suzuki C., Suzuki Y., Takada S., Takahata K., Takayama A., Takayama S., Takemura Y., Takeuchi Y., Tamura H., Tamura N., Tanaka H., Tanaka K., Tanaka M., Tanaka T., Tanaka Y., Toda S., Todo Y., Toi K., Toida M., Tokitani M., Tokuzawa T., Tsuchiya H., Tsujimura T., Tsumori K., Usami S., Velasco J. L., Wang H., Watanabe T. -H., Watanabe T., Yagi J., Yajima M., Yamada H., Yamada I., Yamagishi O., Yamaguchi N., Yamamoto Y., Yanagi N., Yasuhara R., Yatsuka E., Yoshida N., Yoshinuma M., Yoshimura S., Yoshimura Y.

    Nuclear Fusion   57 巻 ( 10 )   2017年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    DOI: 10.1088/1741-4326/aa7fc2

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  143. Erosion of nanostructured tungsten by laser ablation, sputtering and arcing 査読有り

    Dogyun Hwangbo, Shota Kawaguchi, Shin Kajita, Noriyasu Ohno

    Nuclear Materials and Energy   12 巻   頁: 386 - 391   2017年8月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    DOI: 10.1016/j.nme.2017.03.004

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  144. Measuring temperature effects on nano-bubble growth in tungsten with grazing incidence small angle X-ray scattering 査読有り

    Matt Thompson, Russ Doerner, Noriyasu Ohno, Nigel Kirby, Patrick Kluth, Daniel Riley, Cormac Corr

    Nuclear Materials and Energy   12 巻   頁: 1294 - 1297   2017年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Elsevier Ltd  

    W samples were exposed to He plasma in the MAGPIE, NAGDIS-II and PISCES-A across a range of sample temperatures between 473–1123 K. GISAXS was used to quantify the effect of plasma fluence and W surface temperature on He nano-bubble size distributions. In NAGDIS-II at 873 K nano-bubbles are exponentially distributed with mean diameters μ=0.64±0.01nm, similar to the value of μ=0.62±0.01nmfound for the MAGPIE plasma device at the much lower temperature of 473 K. Above ∼900 K nano-bubbles followed an approximately exponential distribution with μ &gt
    0.72 nm demonstrating a significant increase in nano-bubble sizes at higher temperatures.

    DOI: 10.1016/j.nme.2016.11.025

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  145. A Particle-In-Cell approach to particle flux shaping with a surface mask 査読有り

    Kawamura G, Ohno N, Takamura S, Tomita Y

    NUCLEAR MATERIALS AND ENERGY   12 巻   頁: 297 - 301   2017年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    DOI: 10.1016/j.nme.2016.12.017

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  146. Toroidally symmetric/asymmetric effect on the divertor flux due to neon/nitrogen seeding in LHD 査読有り

    Tanaka H., Kawamura G., Masuzaki S., Kobayashi M., Akiyama T., Peterson B. J., Mukai K., Sano R., Dai S. Y., Sakamoto R., Morisaki T., Ohno N.

    NUCLEAR MATERIALS AND ENERGY   12 巻   頁: 241 - 246   2017年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    DOI: 10.1016/j.nme.2016.12.020

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  147. Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX 査読有り

    Sakamoto M, Terakado A, Nojiri K, Ezumi N, Nakashima Y, Sawada K, Ichimura K, Fukumoto M, Oki K, Shimizu K, Ohno N, Masuzaki S, Togo S, Kohagura J, Yoshikawa M

    NUCLEAR MATERIALS AND ENERGY   12 巻   頁: 1004 - 1009   2017年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    DOI: 10.1016/j.nme.2017.05.001

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  148. Fractality and growth of He bubbles in metals 査読有り

    Shin Kajita, Atsushi M. Ito, Noriyasu Ohno

    Physics Letters, Section A: General, Atomic and Solid State Physics   381 巻 ( 29 ) 頁: 2355 - 2362   2017年8月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physics Letters, Section A: General, Atomic and Solid State Physics  

    DOI: 10.1016/j.physleta.2017.05.028

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  149. Field emission from metal surfaces irradiated with helium plasmas 査読有り 国際共著

    Dogyun Hwangbo, Shin Kajita, Noriyasu Ohno, Dmitry Sinelnikov

    IEEE Transactions on Plasma Science   45 巻 ( 8 ) 頁: 2080 - 2086   2017年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE Transactions on Plasma Science  

    DOI: 10.1109/TPS.2017.2679211

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  150. Effects of modified surfaces produced at plasma-facing surface on hydrogen release behavior in the LHD 査読有り

    Nobuta Y, Masuzaki S, Tokitani M, Ashikawa N, Nagata D, Yoshida N, Oya Y, Yajima M, Motojima G, Kasahara H, Miyamoto M, Ohno N, Yamauchi Y

    NUCLEAR MATERIALS AND ENERGY   12 巻   頁: 483 - 487   2017年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Materials and Energy  

    DOI: 10.1016/j.nme.2017.02.025

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  151. Behavior of 23S metastable state He atoms in low-temperature recombining plasmas 査読有り

    S.Kajita, T.Tsujihara, M.Aramaki, H.van der Meiden, H.Oshima, N.Ohno, H.Tanaka, R.Yasuhara, T.Akiyama, K.Fujii, T.Shikama

    Physics of Plasmas   24 巻   頁: 073301(8 pp)   2017年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.4990077

  152. Influence of expanding and contracting magnetic field configurations on detached plasma formation in a linear plasma device 査読有り

    Y.Hayashi, N.Ohno, S.Kajita, H.Tanaka

    Physics of Plasmas   24 巻   頁: 062509(8 pp)   2017年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.4986100

  153. Recent progress of the JT-60SA project 査読有り 国際共著 国際誌

    Shirai H., Barabaschi P., Kamada Y., Maksoud W.A., Aiba N., Akiyama T., Alonso J., Angioni C., Arai T., Arakawa H., Ardellier F., Artaud J.F., Asakura N., Ashikawa N., Barbato E., Barrera G., Baruzzo M., Baulaigue O., Beaufils S., Bécoulet M., Benkadda S., Benoit F., Bettini P., Beurskens M., Bierwage A., Boboc A., Boccaccini L., Bolzonella T., Bonne F., Borba D., Botija J., Bourdelle C., Brolatti G., Bruschi A., Bucalossi J., Cabrera-Pérez S., Canton A., Cardella A., Carvalho I., Challis C., Chapman I., Chiba S., Ciazynski D., Cismondi F., Clement-Lorenzo S., Coccoluto G., Cocilovo V., Coda S., Coelho R., Coletti A., Collin B., Conway G., Corato V., Costa P., Crisanti F., Cristofani C., Cruz N., Cucchiaro A., Dairaku M., Davis S., Day C., de Baar M., de la Luna E., De Tommasi G., De Vellis A., De Vries P., Decker J., Decool P., Delrez C., Di Pace L., Di Pietro E., Disset G., Donati A., Douai D., Dougnac H., Duchateau J.L., Duglue D., Dumas N., Dunai D., Ejiri A., Endo Y., Enoeda M., Falchetto G., Farina D., Farthing J., Fejoz P., Fernandez P., Ferro A., Fiamozzi-Zignani C., Fietz W., Figini L., Frello G., Frosi P., Fujita T., Fukuda T., Fukumoto M., Fukuyama A., Furukawa M., Furukawa M.

    Nuclear Fusion   57 巻 ( 10 )   2017年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    The JT-60SA project has been implemented for the purpose of an early realization of fusion energy. With a powerful and versatile NBI and ECRF system, a flexible plasma-shaping capability, and various kinds of in-vessel coils to suppress MHD instabilities, JT-60SA plays an essential role in addressing the key physics and engineering issues of ITER and DEMO. It aims to achieve the long sustainment of high integrated performance plasmas under the high β N condition required in DEMO. The fabrication and installation of components and systems of JT-60SA procured by the EU and Japan are steadily progressing. The installation of toroidal field (TF) coils around the vacuum vessel started in December 2016. The commissioning of the cryogenic system and power supply system has been implemented in the Naka site, and JT-60SA will start operation in 2019. The JT-60SA research plan covers a wide area of issues in ITER and DEMO relevant operation regimes, and has been regularly updated on the basis of intensive discussion among European and Japanese researchers.

    DOI: 10.1088/1741-4326/aa5d01

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  154. Measurement of Poloidal Flow Profiles Using a Mach Probe Array in HYBTOK-II Tokamak with RMP Fields 査読有り

    Okamoto Masaaki, Sakakibara Satoru, Yoshimoto Naoya, Ohno Takuya, Ohno Noriyasu

    PLASMA AND FUSION RESEARCH   12 巻   頁: 1202027   2017年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.12.1202027

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  155. Observations of sustained phase shifted magnetic islands from externally imposed m/n=1/1 RMP in LHD 査読有り 国際共著

    Narushima Y., Sakakibara S., Suzuki Y., Watanabe K. Y., Ohdachi S., Takemura Y., Yoshinuma M., Ida K., Castejon F., Lopez-Bruna D., Hegna C. C., Kobayashi M., Tanaka H., Akiyama T., Ohno N.

    NUCLEAR FUSION   57 巻 ( 7 ) 頁: 076024   2017年5月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1741-4326/aa6dce

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  156. Molecular activated recombination in divertor simulation plasma on GAMMA 10/PDX 査読有り

    M.Sakamoto, A.Terakado, K.Nojiri, N.Ezumi, Y.Nakashima, K.Sawada, Ichimura, M.Fukumoto, N.Ohno, S.Masuzaki, S.Togo, Kohagura, M.Yoshikawa

    Nuclear Materials and Energy   12 巻   頁: 1004-1009   2017年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  157. Increase in the energy absorption of pulsed plasma by the formation of tungsten nanostructure 査読有り

    D. Sato, N. Ohno, F. Domon, S. Kajita, Y. Kikuchi, I. Sakuma

    Nuclear Fusion   57 巻 ( 6 ) 頁: 066028(8 pp)   2017年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    © 2017 IAEA, Vienna. The synergistic effects of steady-state and pulsed plasma irradiation to material have been investigated in the device NAGDIS-PG (Nagoya DIvertor Simulator with Plasma Gun). The duration of the pulsed plasma was ∼0.25 ms. To investigate the pulsed plasma heat load on the materials, we developed a temperature measurement system using radiation from the sample in a high time resolution. The heat deposited in response to the transient plasma on a tungsten surface was revealed by using this system. When the nanostructures were formed by helium plasma irradiation, the temperature increase on the bulk sample was enhanced. The result suggested that the amount of absorbed energy on the surface was increased by the formation of nanostructures. The possible mechanisms causing the phenomena are discussed with the calculation of a sample temperature in response to the transient heat load.

    DOI: 10.1088/1741-4326/aa67ad

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  158. Tailoring of fuzzy nanostructures on porous tungsten skeleton by helium plasma irradiation 査読有り

    Kajita Shin, Tanaka Hirohiko, Ohno Noriyasu

    JAPANESE JOURNAL OF APPLIED PHYSICS   56 巻 ( 3 ) 頁: 030303(4 pp)   2017年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.7567/JJAP.56.030303

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  159. Plasma detachment in linear devices 査読有り

    Ohno N.

    PLASMA PHYSICS AND CONTROLLED FUSION   59 巻 ( 3 ) 頁: 034007(9 pp)   2017年3月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1361-6587/aa5394

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  160. Localized Density Fluctuation in the Downstream of Detached Plasma 査読有り

    Takeyama Kohei, Ohno Noriyasu, Yoshikawa Masayuki, Tanaka Hirohiko, Kajita Shin

    PLASMA AND FUSION RESEARCH   12 巻 ( 1 ) 頁: 1202007   2017年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.12.1202007

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  161. Transverse motion of a plasma column in a sheet plasma 査読有り

    Onda Takuya, Kajita Shin, Iijima Takaaki, Tonegawa Akira, Ohno Noriyasu, Tanaka Hirohiko

    CONTRIBUTIONS TO PLASMA PHYSICS   57 巻 ( 2 ) 頁: 87 - 93   2017年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/ctpp.201500142

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  162. In Situ TEM Observation of Helium Bubbles Collapsing on Nanostructured Tungsten during Annealing 査読有り

    M. Yajima, N. Yoshida, S. Kajita, and N. Ohno

    Plasma and Fusion Research   11 巻   頁: 1206125   2016年12月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.11.1206125

  163. Measurement of heat diffusion across fuzzy tungsten layer 査読有り

    S.Kajita, T.Yagi, K.Kobayashi, M.Tokitani, N.Ohno

    Results in Physics   6 巻   頁: 877-878   2016年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  164. Plasma detachment study of high density helium plasmas in the Pilot-PSI device 査読有り

    Y.Hayashi, K.Jesko, H.J.van der Meiden, J.W.M.Vernimmen, T.W.Morgan, N.Ohno, S.Kajita, M.Yoshikawa, S.Masuzaki

    Nuclear Fusion   56 巻   頁: 126006(13 pp)   2016年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  165. Enhancement of photocatalytic activity of TiO2 by plasma irradiation 査読有り

    S.Kajita, T.Yoshida, N.Ohno, T.Ishida, D.Kitaoka

    Japanese Journal of Applied Physics   55 巻   頁: 106202(5 pp)   2016年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  166. Fuzzy nanostructure growth on Ta/Fe by He plasma irradiation 査読有り

    S.Kajita, T.Ishida, N.Ohno, D.Hwangbo, T.Yoshida

    Scientific Reports   6 巻   頁: 30380   2016年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1038/srep30380

  167. Statistical Analysis of Particle Flux Flowing into the End-Target in between Atached and Detached Sttes in the Linear Divertor Plasma Simulator NAGDIS-II 査読有り

    H.Tanaka, N.Ohno, T.Onda, K.Takeyama, S.Kajita, T.Kuwabara, Y.Tsuji

    Contrib. Plasma Phys.   56 巻 ( 6-8 ) 頁: 723-728   2016年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  168. Measurement of thermophysical property of plasma forming tungsten nanofiber layer 査読有り

    S.Kajita, T.Yagi, K.Kobayashi, M.Tokitani, N.Ohno

    Japanese Journal of Applied Physics   55 巻   頁: 056203(5 pp)   2016年4月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.7567/JJAP.55.056203

  169. Dynamics of three-dimensional radiative structures during RMP assisted detached plasmas on the large helical device and its comparison with EMC3-EIRENE modeling 査読有り 国際共著

    Shwetang N. Pandya, Byron J. Peterson, Masahiro Kobayashi, Katsumi Ida, Kiyofumi Mukai, Ryuichi Sano, Junichi Miyazawa, Hirohiko Tanaka, Suguru Masuzaki, Tsuyoshi Akiyama, Gen Motojima, Noriyasu Ohno

    Nuclear Fusion   56 巻 ( 4 ) 頁: 046002   2016年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    DOI: 10.1088/0029-5515/56/4/046002

    Web of Science

    Scopus

  170. Strong Reduction of Ion Flux to a Target Plate in a Magnetically Contracting Detached Plasma 査読有り

    Y.Hayashi, H.Nishikata, N.Ohno, S.Kajita

    Plasma and Fusion Research: Rapid Communications   11 巻   頁: 1202005(2 pp)   2016年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.11.1202005

  171. Plasma flow in peripheral region of detached plasma in linear plasma device 査読有り

    Y.Hayashi, N.Ohno, S.Kajita, H.Tanaka

    Physics of Plasmas   23 巻   頁: 012511(7 pp)   2016年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.4940310

  172. Arc tracks on nanostructured surfaces after microbreakdowns 査読有り

    D.Sinelnikov, D.Bulgadaryan, D.Hwangbo, S.Kajita, D.Kolodko, V.Kurnaev, N.Ohno

    Journal of Physics:Conference Series   748 巻   頁: 012012(6 pp)   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  173. Detailed Analysis of Plasma Resistivity in Detached Recombining Plasmas 査読有り

    H.Nishikata, Y.Hayashi, N.Ohno, S.Kajita, T.Kuwabara

    Contrib. Plasma Phys.   56 巻 ( 6-8 ) 頁: 717-722   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  174. Modeling of Linear Divertor Plasma Simulator Experiments with Three-dimensional Target Structure by Using EMC3-EIRENE Code 査読有り

    T.Kubawara, H.Tanaka, G.Kawamura, N.Ohno, H.Nishikata, M.Kobayashi, Y.Feng

    Contrib. Plasma Phys.   56 巻 ( 6-8 ) 頁: 598-603   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  175. Effects of Modified Surfaces Produced at Plasma-Facing Surface on Hydrogen Isotopes and Helium Release Behavior in the LHD 査読有り

    Y.Nobuta, S.Masuzaki, M.Tokitani, D.Nagata, N.Ashikawa, N.Yoshida, Y.Oya, M.Yajima, G.Motojima, H.Kasahara, M.Miyamoto, N.Ohno

    IAEA proccedings     頁: MPT/P5-19(9 pp)   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  176. Photon Trapping Effects in DEMO Divertor Plasma 査読有り

    K. Hoshino, K. Sawada, R. Idei, S. Tokunaga, N. Asakura, K. Shimizu, and N. Ohno

    Contrib. Plasma Phys.   56 巻   頁: 657-662   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  177. Investigation of arcing on fiber-formed nanostructured tungsten by pulsed plasma during steady state plasma irradiation 査読有り

    M. Yajima, N. Ohno, S. Kajita, G. De Temmerman, K. Bystrov, S. Bardin

    Fusion Engineering and Design   112 巻   頁: 156-161   2016年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  178. Vacuum Breakdown from Nanostructured Fuzzy Surfaces 査読有り 国際共著 国際誌

    Sinelnikov D., Bulgadaryan D., Hwangbo D., Kajita S., Kolodko D., Kurnaev V., Ohno N.

    PROCEEDINGS OF THE 27TH INTERNATIONAL SYMPOSIUM ON DISCHARGES AND ELECTRICAL INSULATION IN VACUUM (ISDEIV), VOL 1     頁: 68 - 71   2016年

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Web of Science

  179. Morphology and optical property changes of nanostructured tungsten in LHD 査読有り

    S.Kajita, T.Akiyama, N.Yoshida, M.Tokitani, M.Yajima, N.Ohno

    Plasma and Fusion Research   10 巻   頁: 1402083(9 pp)   2015年12月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.10.1402083

  180. Sulfur K-edge XANES for methylene blue in photocatalytic reaction over WO<inf>3</inf> nanomaterials 査読有り 国際誌

    K. Komori, T. Yoshida, T. Nomoto, M. Yamamoto, C. Tsukada, S. Yagi, M. Yajima, S. Kajita, N. Ohno

    Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms   365 巻   頁: 35 - 38   2015年12月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms  

    DOI: 10.1016/j.nimb.2015.07.035

    Scopus

  181. Increase in the work function of W/WO3 by helium plasma irradiation 査読有り

    S.Kajita, A.Ohta, T.Ishida, K.Makihara, T.Yoshida, N.Ohno

    Japanese Journal of Applied Physics   54 巻   頁: 126201(6 pp)   2015年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  182. 3D effects of edge magnetic field configuration on divertor/scrape-off layer transport and optimization possibilities for a future reactor 査読有り 国際共著 国際誌

    M. Kobayashi, Y. Xu, K. Ida, Y. Corre, Y. Feng, O. Schmitz, H. Frerichs, F. L. Tabares, T. E. Evans, J. W. Coenen, Y. Liang, A. Bader, K. Itoh, H. Yamada, Ph Ghendrih, G. Ciraolo, D. Tafalla, A. Lopez-Fraguas, H. Y. Guo, Z. Y. Cui, D. Reiter, N. Asakura, U. Wenzel, S. Morita, N. Ohno, B. J. Peterson, S. Masuzaki

    Nuclear Fusion   55 巻 ( 10 ) 頁: 104021   2015年9月

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    記述言語:英語   出版者・発行元:Nuclear Fusion  

    © 2015 IAEA, Vienna. This paper assesses the three-dimensional (3D) effects of the edge magnetic field structure on divertor/scrape-off layer transport, based on an inter-machine comparison of experimental data and on the recent progress of 3D edge transport simulation. The 3D effects are elucidated as a consequence of competition between transports parallel () and perpendicular () to the magnetic field, in open field lines cut by divertor plates, or in magnetic islands. The competition has strong impacts on divertor functions, such as determination of the divertor density regime, impurity screening and detachment control. The effects of magnetic perturbation on the edge electric field and turbulent transport are also discussed. Parameterization to measure the 3D effects on the edge transport is attempted for the individual divertor functions. Based on the suggested key parameters, an operation domain of the 3D divertor configuration is discussed for future devices.

    DOI: 10.1088/0029-5515/55/10/104021

    Scopus

  183. Initiation of arcing on tungsten surface exposed to steady state He Plasmas 査読有り

    S.Kajita, Y.Noiri, N.Ohno

    Physica Scripta   90 巻 ( 9 ) 頁: 095604(7 pp)   2015年8月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0031-8949/90/9/095604

  184. Development of Impurity Seeding and Radiation Enhancement in the Helical Divertor of LHD 査読有り

    K.Mukai, S.Masuzaki, B.Peterson, T.Akiyama, M.Kobayashi, H.Tanaka, S.Pandya, R.Sano, G.Motojima, N.Ohno, T.Morisaki, C.Suzuki, I.Murakami, J.Miyazawa, N.Tamura, S.Yoshimura, I.Yamada, R.Yasuhara, H.Funaba, K.Tanaka

    Nuclear Fusion   55 巻   頁: 83016(9 pp)   2015年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/55/8/083016

  185. Overview of transport and MHD stability study:focusing on the impact of magnetic field topology in the Large Helical Device 査読有り

    K. Ida, K. Nagaoka, S. Inagaki, H. Kasahara, T. Evans, M. Yoshinuma, K. Kamiya, S. Ohdach, M. Osakabe, M. Kobayashi, S. Sudo1,, K. Itoh, T. Akiyama, M. Emoto, A. Dinklage, X. Du, K. Fujii, M. Goto, T. Goto, M. Hasuo, C. Hidalgo, K. Ichiguchi, A. Ishizawa, M. Jakubowski, G. Kawamura, D. Kato, S. Morita, K. Mukai, I. Murakami, S. Murakami, Y. Narushima, M. Nunami, N. Ohno, N. Pablant, S. Sakakibara, T. Seki, T. Shimozuma, M. Shoji, K. Tanaka, T. Tokuzawa, Y. Todo, H. Wang, M. Yokoyama, H. Yamada, Y. Takeiri, T. Mutoh, S. Imagawa, T. Mito, Y. Nagayama, K.Y. Watanabe, N. Ashikawa, H. Chikaraishi, A. Ejiri, M. Furukawa, T. Fujita, S. Hamaguchi, H. Igami1, M. Isobe, S. Masuzaki, T. Morisaki, G. Motojima, K. Nagasaki, H. Nakano, Y. Oya, C. Suzuki, Y. Suzuki, R. Sakamoto, M. Sakamoto, A. Sanpei, H. Takahashi, H. Tsuchiya, M. Tokitani, Y. Ueda, Y. Yoshimura1, S. Yamamoto, K. Nishimura, H. Sugama, T. Yamamoto, H. Idei, A. Isayama, S. Kitajima, S. Masamune, K. Shinohara, P.S. Bawankar, E. Bernard, M. von Berke, H. Funaba, X.L. Huang, T. Ii, T. Ido, K. Ikeda, S. Kamio, R. Kumazawa, T. Kobayashi, C. Moon, S. Muto, J. Miyazawa, T. Ming, Y. Nakamura, S. Nishimura, K. Ogawa, T. Ozaki, T. Oishi, M. Ohno, S. Pandya, A. Shimizu, R. Seki, R. Sano, K. Saito, H. Sakaue, Y. Takemura, K. Tsumori, N. Tamura, H. Tanaka, K. Toi, B. Wieland, I. Yamada, R. Yasuhara, H. Zhang2, O. Kaneko, A. Komori and Collaborators

    Nuclear Fusion   55 巻 ( 10 ) 頁: 104018   2015年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/55/10/104018

  186. Sulfur E-edge XANES for methylene blue in photocatalytic reaction over WO3 nanomaterials 査読有り

    K.Komori, T.Yoshida, T.Nomoto, M.Yamamoto, C.Tsukada, S.Yagi, M.Yajima, S.Kajita, N.Ohno

    Nuclear Instruments and Methods in Physics Research B   365 巻   頁: 35-38   2015年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  187. Molecular dynamics and Monte Carlo hybrid simulation for fuzzy tungsten nanostructure formation 査読有り

    A.M.Ito, A.Takayama, Y.Oda, T.Tamura, R.Kobayashi, T.Hattori, S.Ogata, N.Ohno, S.Kajita, M.Yajima, Y.Noiri, Y.Yoshimoto, S.Saito, S.Takamura, T.Murashima, M.Miyamoto, H.Nakamura

    Nuclear Fusion   55 巻 ( 7 ) 頁: 073013   2015年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/55/7/073013

  188. Growth of multifractal tungsten nanostructure by He bubble induced directional swelling 査読有り

    S.Kajita, N.Yoshida, N.Ohno, Y.Tsuji

    New Journal of Physics   17 巻   頁: 043038(14 pp)   2015年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  189. Influence of Deuterium Retention on Secondary Electron Emission from Graphite under Deuterium Plasma Exposure 査読有り

    T.Kaneko, N.Ohno, Y.Nakamura, M.Yamagiwa, N.Matsunami, S.Kajita, M.Takagi

    Plasma and Fusion Research: Regular Articles   10 巻   頁: 1402009(5 pp)   2015年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  190. Nanostructure growth by helium plasma irradiation to tungsten in sputtering regime 査読有り

    Y.Noiri, S.Kajita, N.Ohno

    Journal of Nuclear Materials   463 巻 ( C ) 頁: 285 - 288   2015年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j/jnucmat.2015.01.036

  191. Flow damping due to stochastization of the magnetic field 査読有り

    K.Ida, M.Yoshinuma, H.Tsuchiya, T.Kobayashi, C.Suzuki, M.Yokoyama, A.Shimizu, K.Nagaoka, S.Inagaki, K.Itoh & the LHD Experiment Group (36th author)

    Nature Communications     2015年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1038/ncomms6816

  192. Hybrid simulation research on formation mechanism of tungsten nanostructure induced by helium plasma irradiation 査読有り

    A.M. Ito, A.Takayama, Y.Oda, T.Tamura, R.Kobayashi, T.Hattori, S.Ogata, N.Ohno, S.Kajita, M.Yajima, Y.Noiri, Y.Yoshimoto, S.Saito, S.Takamura, T.Murashima, M.Miyamoto, H.Nakamura

    Journal of Nuclear Materials   463 巻   頁: 109 - 115   2015年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2015.01.018

  193. Multi-pin Langmuir probe measurement for identification of blob propagation characteristics in the Large Helical Device 査読有り

    H.Tanaka, S.Masuzaki, N.Ohno, T.Morisaki, Y.Tsuji, LHD Experiment Group

    Journal of Nuclear Materials   463 巻   頁: 761-764   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  194. Evolution of radiation profiles during detached plasmas and radiative collapse in LHD 査読有り

    S.N.Pandya, B.J.Peterson, M.Kobayashi, K.Mukai, R.Sano, H.Tanaka, S.Masuzaki, J.Miyazawa, T.Akiyama.G.Motojima N.Ohno

    Journal of Nuclear Materials   463 巻   頁: 551-554   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  195. Nanostructure growth by helium plasma irrdaition to tungsten in sputtering regime 査読有り

    Y.Noiri, S.Kajita, N.Ohno

    Journal of Nuclear Materials   463 巻   頁: 285-288   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  196. Progress of divertor simulation research toward the realization of detached palsam using a large tandem mirror device 査読有り

    Y.Nakashima, H.Takeda, K.Ichimura, K.Hosoi, K.Oki, M.Sakamoto, M.Hirata, M.Ichimura, R.Ikezoe, T.Imai, M.Iwamoto, Y.Hosoda, I.Katanuma, T.Kariya, S.Kigure, J.Kohagura, R.Minami, T.Numakura, S.Takahashi, M.Yoshikawa, N.Asakura, M.Fukumoto, A.Hatayama, Y.Hirooka, S.Kado, H.Kubo, S.Masuzaki, H.Matsuura, S.Nagata, N.Nishino, N.Ohno, A.Sagara, T.Shikama, M.Shoji, A.Tonegawa, Y.Ueda

    Journal of Nuclear Materials   463 巻   頁: 537-540   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  197. Impact of 3D magnetic field structure on boundary and divertor plasmas in stellarator /heliotron devices 査読有り

    M.Kobayasahi, Y.Feng, Y.Xu, F.L.Tabares, K.Ida, O.Schmitz, T.E.Evans, H.Frerichs, Y.Liang, A.bader, K.Itoh, H.Yamada, Ph.Ghendrih, G.Ciraolo, D.Tafalla, A.Lopez-Fraguas, H.Y.Guo, Z.Y.Cui, D.Reiter, N.Asakura, U.Wenzel, S.Morita, N.Ohno, B.J.Peterson, S.Masuzaki

    Journal of Nuclear Materials   463 巻   頁: 2-10   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  198. Global helium particle balance in LHD 査読有り

    G.Motojima, S.Masuzaki, M.Tokitani, H.Kasahara, Y.Yoshimura, M.Kobayashi, R.Sakamoto, T.Morisaki, J.Miyazawa, T.Akiyama, N.Ohno, T.Mutoh, H.Yamada, LHD Experiment Group

    Journal of Nuclear Materials   463 巻   頁: 1080-1083   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  199. Radiated power distributions in impurity-seeded plasmas in LHD 査読有り

    T.Morisaki, K.Oyama, N.Tamura, S.Masuzaki, T.Akiyama, G.Motojima, J.Miyazawa, B.J.Peterson, N.Ohno, H.Yamada, LHD Experiment Group

    Journal of Nuclear Materials   463 巻   頁: 640-643   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  200. Simulation Study of Power Load with Impurity Seeding in Advanced Divertor "Short Super-X Divertor" for a Tokamak Reactor 査読有り

    N.Asakura, K.Hoshino, K.Shimizu, K.Shinya, H.Utoh, S.Tokunaga, K.Tobita, N.Ohno

    Journal of Nuclear Materials   463 巻   頁: 1238-1242   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2015.01.068

  201. Influence of external resonant magnetic perturbation field on edge plasma of small tokamak HYBTOK-II 査読有り

    Y.Hayashi, Y.Suzuki, N.Ohno, M.Okamoto, Y.Kikuchi, S.Sakakibara, K.Watanabe, Y.Takemura

    Journal of Nuclear Materials   463 巻   頁: 463-466   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2014.12.018

  202. In-situ measurement of deuterium retention in W under plasma exposure 査読有り

    T. Watanabe, T. Kaneko, N. Matsunami, N. Ohno, S. Kajita, T. Kuwabara

    Journal of Nuclear Materials   463 巻   頁: 1049-1052   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2014.12.011

  203. CORRELATION ANALYSIS OF 3-4 KILOHERTZ CORE AND EDGE DENSITY FLUCTUATIONS IN THE GAMMA 10 TANDEM MIRROR DEVICE 査読有り

    H. Tanaka, M. Sakamoto, K. Furutachi, K. Oki, M. Mizuguchi, Y. Nagatsuka, M. Yoshikawa, R. Nohara, M. Yoshikawa, J. Kohagura, N. Ohno, and Y. Tsuji

    Fusion Sci. Tech.   68 巻   頁: 125-129   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  204. Influence of Deuterium Retention on Secondary Electron Emission from Graphite under Deuterium Plasma Exposure 査読有り

    T.Kaneko, N.Ohno, Y.Nakamura, M.Yamagiwa, N.Matsunami, S.Kajita, M.Takagi

    Plasma and Fusion Research   10 巻   頁: 1402009(5 pp)   2015年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  205. Arc spot grouping: An entanglement of arc spot cells 査読有り

    S.Kajita, D.Hwangbo, N.Ohno, M.M.Tsventoukh, S.A.Barengolts

    Journal of Applied Physics   116 巻   頁: 233302   2014年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.4904917

  206. Current Activities in the Interactive Joint Research at Tohoku University - Advanced Evaluation of Radiation Effects on Fusion Materials - 査読有り

    H.Kurishita, M.Hatakeyama, M.Narui, S.Matsuo, T.Shikama, K.Tada, N.Ohno, T.Takeuchi, Y.Hatano, M.Nishiura, Y.Nakashima, H.Watanabe, K.Tokunaga, T.Hino, Y.Ueda, T.Muroga, A.Sagara, O.Kaneko

    Plasma and Fusion Research   9 巻   頁: 3405136(4 pp)   2014年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.9.3405136

  207. Compact and high-particle-flux thermal-lithium-beam probe system for measurement of two-dimensional electron density profile 査読有り

    Y.Shibata, T.Manabe, S.Kajita, N.Ohno, M.Takagi, H.Tsuchiya, T.Morisaki

    Rev. Sci. Instrum.   85 巻   頁: 93510(6 pp)   2014年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.4895718

  208. Application of Nanostructured Tungsten Fabricated by Helium Plasma Irradiation for Photoinduced Decolorization of Methylene Blue 査読有り

    K.Komori, T.Yoshida, S.Yagi, H.Yoshida, M.Yajima, S.Kajita, N.Ohno

    e-J.Surf.Sci.Nanotech.(e-Journal of Surface Science and Nanotechnology)   12 巻   頁: 343-348   2014年7月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1380/ejssnt.2014.343

  209. Fractality of self-grown nanostructured tungsten by He plasma irradiation 査読有り

    S.Kajita, Y.Tsuji, N.Ohno

    Physics Letters A   378 巻   頁: 2533-2538   2014年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  210. In situ observation of structural change of nanostructured tungsten during annealing 査読有り

    M.Yajima, N.Yoshida, S.Kajita, M.Tokitani, T.Baba, N.Ohno

    Journal of Nuclear Materials   449 巻 ( 1-3 ) 頁: 9-14   2014年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  211. Influence of plasma-neutral collisions on probe measurements in atmospheric pressure plasmas 査読有り 国際誌

    Contributions to Plasma Physics   54 巻 ( 3 ) 頁: 304 - 307   2014年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Contributions to Plasma Physics  

    DOI: 10.1002/ctpp.201410074

    Scopus

  212. In situ measurement of deuterium retention in graphite under successive exposure to deuterium and hydrogen plasmas 査読有り

    N.Ohno, Y.Nakamura, M.Yamagiwa, T.Kaneko, N.Matsunami, S.Kajita, M.Takagi

    Phys. Scr.   T159 巻   頁: 014053(4 pp)   2014年4月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  213. A plasma source driven predator-prey like mechanism as a potential cause of spiraling intermittencies in linear plasma devices 査読有り

    D.Reiser, N.Ohno, H.Tanaka, L.Vela

    Physics of Plasmas   21 巻   頁: 032302(10 pp)   2014年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  214. Surface modification of titanium using He plasma 査読有り

    S.Kajita, D.Kitaoka, N.Ohno, R.Yoshihara, N.Yoshida, T.Yoshida

    Applied Surface Science   303 巻   頁: 438-445   2014年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  215. Thermal response of nanostructured tungsten 査読有り

    S.Kajita, G.De Temmerman, T.Morgan, S.van Eden, T. de Kruif, N.Ohno

    Nuclear Fusion   54 巻   頁: 033005(10 pp)   2014年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  216. Helium plasma irradiation on single crystal tungsten and undersized atom doped tungsten alloys 査読有り 国際誌

    Kajita Shin, Yoshida Naoaki, Ohno Noriyasu, Hirahata Yuki, Yoshihara Reiko

    PHYSICA SCRIPTA   89 巻 ( 2 )   2014年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physica Scripta  

    DOI: 10.1088/0031-8949/89/02/025602

    Web of Science

    Scopus

  217. Optical design for divertor Thomson scattering system for JT-60SA 査読有り

    S.Kajita, A.Enokuchi, T.Hatae, K.Itami, T.Hamano, S.Kado, N.Ohno, N.Takeyama

    Fusion Engineering and Design   89 巻 ( 1 ) 頁: 69-76   2014年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  218. Helium plasma irradiation on single crystal tungsten and undersized atom doped tunsten alloys 査読有り

    S.Kajita, N.Yoshida, N.Ohno, Y.Hirahata, R.Yoshihara

    Phys. Scr.   89 巻   頁: 025602(7 pp)   2014年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  219. Modified Power Transmission Factor of Tungsten in Plasmas with Hot Electron Component 査読有り

    S.Takamura, S.Ono, N.Ohno

    Contrib. Plasma Phys.   54 巻 ( 4-6 ) 頁: 474-478   2014年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  220. Transition in velocity and grouping of arc spot on different nanostructured tungsten electrodes 査読有り

    Hwangbo D.

    Results in Physics   4 巻   頁: 33 - 39   2014年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Results in Physics  

    DOI: 10.1016/j.rinp.2014.03.001

    Web of Science

    Scopus

  221. Spectroscopic Study and Motion Analysis of Arc Spot Initiated on Nanostructured Tungsten 査読有り

    D.Hwangbo, S.Kajita, M.Osaka, N.Ohno

    Jpn. J. Appl. Phys.   52 巻   頁: 11NC02(6 pp)   2013年11月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.7567/JJAP.52.11NC02

  222. Low-energy helium irradiation on in-vessel mirror materials 査読有り

    S.Kajita, M.Tokitani, T.Saeki, N.Ohno, N.Yoshida

    Journal of Nuclear Materials   442 巻 ( 1-3, Supplement 1 ) 頁: S515-S519   2013年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  223. Helium effects on tungsten surface morphology and deuterium retention 査読有り

    Y.Ueda, H.Y.Peng, H.T.Lee, N.Ohno, S.Kajita, N.Yoshida, R.Doerner, G.De Temmerman, V.Alimov, G.Wright

    Journal of Nuclear Materials   442 巻 ( 1-3 ) 頁: S267-S272   2013年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  224. Properties of deposited layer formed by interaction with Be seede D-He mixture plasma and tungsten 査読有り

    K.Tokunaga, M.J.Baldwin, D.Nishijima, R.P.Doerner, S.Nagata, B.Tsuchiya, H.Kurishita, T.Fujiwara, K.Araki, Y.Miyamoto, N.Ohno, Y.Ueda

    Journal of Nuclear Materials   442 巻 ( 1-3 ) 頁: S313-S319   2013年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  225. Characterization of Gun Plasma Penetrated into a Steady State Plasma Device 査読有り

    S.Kajita, T.Akiyama, T.Nihashi, M.Osaka, N. Ohno, Y.Kikuchi, I.Sakuma, M.Nagata

    IEEE TRANSACTIONS ON PLASMA SCIENCE   41 巻 ( 11 ) 頁: 3122-3128   2013年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  226. Field emission property of nanostructured tungsten formed by helium plasma irradiation 査読有り

    Kajita S.

    Fusion Engineering and Design   88 巻 ( 11 ) 頁: 2842 - 2847   2013年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Fusion Engineering and Design  

    DOI: 10.1016/j.fusengdes.2013.05.014

    Web of Science

    Scopus

  227. Progress of the JT-60SA project 査読有り 国際共著 国際誌

    Kamada Y., Barabaschi P., Ishida S., Abdel Maksoud W., Aiba N., Akino N., Akiyama T., Alonso J., Angioni C., Arai T., Arakawa H., Ardellier F., Artaud J., Asakawa S., Asakura N., Ashikawa N., Balaguer D., Barbato E., Barrera G., Baruzzo M., Baulaigue O., Bayetti P., Bécoulet M., Benkadda S., Benoit F., Besi U., Beurskens M., Boccaccini L., Bolzonella T., Borba D., Botija J., Bourdelle C., Brolatti G., Bruschi A., Bucalossi J., Cara P., Challis C., Chantant M., Chapman I., Chesny P., Chiba S., Ciayznski D., Cismondi F., Cocilovo V., Coletti R., Coletti A., Collins B., Conway G., Corato V., Costa P., Cucchiaro A., Dael A., Davis S., Day C., De Baar M., Decool P., Della Corte A., Delrez C., De Vries P., Decker J., Di Zenobio A., Di Pace L., Di Pietro E., Disset G., Donati A., Douai D., Dougnac H., Drotziger S., Duchateau J.L., Duglue D., Dumas N., Ejiri A., Endo Y., Farina D., Fernandez P., Ferro A., Fietz W., Figini L., Fslchetto G., Fujita T., Fukuda T., Fukumoto M., Fukuyama A., Furukawa M., Furukawa M., Gaio E., Garcia J., Garzotti L., Gauthier E., Genini L., Geraud A., Ginoulhiac G., Giruzzi G., Gomez Carrasco B., Gonde R., Goniche M., Gouat P., Gros G., Haga S.

    Nuclear Fusion   53 巻 ( 10 )   2013年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    The JT-60SA project implemented by Japan and Europe is progressing on schedule towards the first plasma in March 2019. After careful R&D, procurements of the major components have entered their manufacturing stages. In parallel, disassembly of JT-60U has been completed on time, and the JT-60SA tokamak assembly is expected to start in January 2013. The JT-60SA device, a highly shaped large superconducting tokamak with a variety of plasma control actuators, has been designed in order to contribute to ITER and to complement ITER in all the major areas of fusion plasma development necessary to decide DEMO reactor construction. Detailed assessments and prediction studies of the JT-60SA plasma regimes have confirmed these capabilities: using ITER- and DEMO-relevant plasma regimes, heating conditions, and its sufficiently long discharge duration, JT-60SA enables studies on magnetohydrodynamic stability at high beta, heat/particle/momentum transport, high-energy ion physics, pedestal physics including edge localized mode control, and divertor physics. By integrating these studies, the project provides 'simultaneous and steady-state sustainment of the key performance characteristics required for DEMO' with integrated control scenario development.

    DOI: 10.1088/0029-5515/53/10/104010

    Scopus

  228. Control of 3D edge radiation structure with resonant magnetic perturbation fields applied to the stochastic layer and stabilization of radiative divertor plasma in LHD 査読有り

    M. Kobayashi, S. Masuzaki, I. Yamada, Y. Narushima, C. Suzuki, N. Tamura, B. J. Peterson, S. Morita, C. F. Dong, N. Ohno, S. Yoshimura, Y. Feng, M. Goto, K. Sato, T. Akiyama, K. Tanaka

    Nuclear Fusion   53 巻 ( 9 )   2013年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    It is found that resonant magnetic perturbation (RMP) fields have a stabilizing effect on the radiating edge plasma, realizing stable sustainment of radiative divertor (RD) operation in the Large Helical Device (LHD). Without RMP, thermal instability leads to radiative collapse. Divertor power load is reduced by a factor of 3-10 during the RMP-assisted RD phase, while maintaining relatively good core plasma confinement with confinement enhancement factor . It has also been demonstrated that the RMP field itself can initiate transition to RD operation by increasing perturbation strength, while keeping constant density and injection power. The results show a possibility of a new control knob for divertor power load in a 3D magnetic field configuration. It is also found that after the transition to RD, the energy confinement enhancement factor based on ISS04 scaling increases by a factor of 1.4 compared with the attached phase. The operation range of the RMP-assisted RD is identified in terms of RMP strength and radial location of the resonance layer of the RMP. A 3D edge radiation structure is analysed using the edge transport code EMC3-EIRENE and the results are compared with experiments. The comparison indicates that the application of RMP modulates the 3D edge radiation structure such that an intense radiation appears around the X-point of the m/n = 1/1 island in the case with RMP, while it is located at the inboard side without RMP. © 2013 IAEA, Vienna.

    DOI: 10.1088/0029-5515/53/9/093032

    Scopus

  229. Growth Annealing Equilibrium of Tungsten Nanostructures by Helium Plasma Irradiation in Non Eroding Regimes 査読有り

    S.Kajita, N.Ohno, M.Yajima, J.Kato

    Journal of Nuclear Materials   440 巻 ( 1-3 ) 頁: 55-62   2013年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  230. Influence of crystal orientation on damages of tungsten exposed to helium plasma 査読有り

    N.Ohno, Y.Hirahata, M.Yamagiwa, S.Kajita, M.Takagi, N.Yoshida, R.Yoshihara, T.Tokunaga, M.Tokitani

    Journal of Nuclear Materials   438 巻   頁: S879-S882   2013年7月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  231. Study of Hydrogen Isotopes Behavior in Carbon Based Materials with In-Situ Ion Beam Analysis under Plasma Exposure 査読有り

    Y.Nakamura, M.Yamagiwa, T.Kaneko, N.Matsunami, N.Ohno, S.Kajita, M.Takagi, M.Tokitani, S.Masuzaki

    Journal of Nuclear Materials   438 巻   頁: S1036-S1039   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  232. Tritium retention in nanostructured tungsten with large effective surface area 査読有り

    M.Yajima, Y.Hatano, S.Kajita, J.Shi, M.Hara, N.Ohno

    Journal of Nuclear Materials   438 巻   頁: S1142-S1145   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  233. Enhancement of multi-pulse laser induced damage threshold on Cu mirror under vacuum condition 査読有り

    S.Kajita, R.Yasuhara, M.Sato, N.Ohno, M.Tokitani, N.Yoshida

    Optics Express   21 巻 ( 14 ) 頁: 17275-17284   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  234. Development of steady/transient dual plasma irradiation device using a plasma gun 査読有り

    S.Kajita, N.Ohno, T.Akiyama, T.Nihashi, T.Uchiyama, M.Osaka, Y.Kikuchi, M.Nagata

    Journal of Nuclear Materials   438 巻   頁: S707-S710   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  235. Edge and divertor plasma measurements with ion sensitive and Mach probes in LHD 査読有り

    Y.Hayashi, N.Ezumi, S.Masuzaki, H.Tanaka, M.Kobayashi, K.Sawada, N.Ohno, the LHD Experiment Group

    Journal of Nuclear Materials   438 巻   頁: S1228-S1231   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  236. Tritium retention in nanostructured tungsten with large effective surface area 査読有り

    M.Yajima, Y.Hatano, S.Kajita, J.Shi, M.Hara, N.Ohno

    Journal of Nuclear Materials   438 巻   頁: S1142-S1145   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  237. Study of hydrogen isotopes behavior in carbon based materials with in situ ion beam analysis under plasma exposure 査読有り

    Y. Nakamura, M. Yamagiwa, T. Kaneko, N. Matsunami, N. Ohno, S. Kajita, M. Takagi, M. Tokitani, S. Masuzaki

    Journal of Nuclear Materials   438 巻   頁: S1036-S1039   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  238. Influence of crystal orientation on damages of tungsten exposed to helium plasma 査読有り

    N.Ohno, Y.Hirahata, M.Yamagiwa, S.Kajita, M.Takagi, N.Yoshida, R.Yoshihara, T.Tokunaga, M.Tokitani

    Journal of Nuclear Materials   438 巻   頁: S879-S882   2013年7月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  239. Thermal radiation characteristics and direc evidence of tungsten cooling on the way to nanostructure formation on its surface 査読有り

    S.Takamura, T.Miyamoto, N.Ohno

    Journal of Nuclear Materials   438 巻   頁: S814-S817   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  240. Recent results of divertor simulation research using an end-cell of a large tandem mirror device 査読有り

    Y. Nakashima, H. Takeda, K. Ichimura, K. Hosoi, M. Sakamoto, M. Hirata, M. Ichimura, R. Ikezoe, T. Imai, T. Ishii, T. Kariya, I. Katanuma, J. Kohagura, R. Minami, T. Numakura, H. Ueda, M. Yoshikawa, N. Asakura, T. Furuta, A. Hatayama, et al.(N.Ohno No.27)

    Journal of Nuclear Materials   438 巻   頁: S738-S741   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  241. Kinetic effect of high energy ions on the temperature profile in the boundary plasma region 査読有り

    N.Ezumi, Y.Hayashi, K.Todoroki, K.Okazaki, H.Tanaka, S.Masuzaki, N.Ohno

    Journal of Nuclear Materials   438 巻   頁: S472-S474   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  242. Divertor heat and particle control experiments on the large helical device 査読有り

    S. Masuzaki, M.Kobayashi, T.Akiyama, N.Ohno, T.Morisaki, et al.

    Journal of Nuclear Materials   438 巻   頁: S133-S138   2013年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  243. Properties of deposited layer formed by interaction with Be seeded D-He mixture plasma and tungsten 査読有り 国際共著 国際誌

    Tokunaga K., Baldwin M.J., Nishijima D., Doerner R.P., Nagata S., Tsuchiya B., Kurishita H., Fujiwara T., Araki K., Miyamoto Y., Ohno N., Ueda Y.

    Journal of Nuclear Materials   442 巻 ( 1-3 SUPPL.1 )   2013年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Nuclear Materials  

    Be-seeded, high-flux, deuterium/helium mixture plasma exposure experiments on tungsten target materials have been performed to simulate ITER all tungsten divertor erosion/modification and deposition phenomena. The exposure conditions are kept fixed at a typical low-ion-energy of 60 eV and a flux of 3-6 × 1022/m2/s. Sample temperature is 1123 K and plasma exposure times spanning 1050-10,100 s are explored. The typical ratio of He/D ions is 0.2 and Be content is 0.2%. A He-induced nanostructure layer is formed on the exposure surfaces of tungsten materials and the surface of the nanostructure is covered by a thin layer of Be and O. A fraction of the re-eroded Be from the target is deposited on a glassy carbon plate with line of sight to the tungsten target. Rutherford backscattering spectrometry analyses show that the Be redeposit layer is in the form of laminae. Small amounts of Mo, W and C are also found in the redeposited Be layer. Elastic recoil detection analyses show that D, He and H are also included in the redeposited Be layer. © 2013 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jnucmat.2013.05.006

    Scopus

  244. Field Emission Property of Nanostuructured Tungsten Formed by Helium Plasma Irradiation 査読有り

    S.Kajita, N.Ohno, Y.Hirahata, M.Hiramatsu

    Journal of Fusion Engineering and Design   88 巻   頁: 2842-2847   2013年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  245. Investigation of Advanced Divertor Magnetic Configuration for Demo Tokamak Reactor 査読有り

    N.Asakura, K.Shinya, K.Tobita, K.Hoshino, K.Shimizu, H.Utoh, Y.Someya, M.Nakamura, N.Ohno, M.Kobayashi, H.Tanaka

    Transactions of Fusion Science and Technology   63 巻 ( 1T ) 頁: 70-75   2013年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  246. Power Transmission Factor for Tungsten Target W/WO Fiber-form Nanostructure in He Plasmas with Hot Electron Component using Compact Plasma Device AIT-PID 査読有り

    S.Takamura, T.Miyamoto, N.Ohno

    Transactions of Fusion Science and Technology   63 巻   頁: 225-228   2013年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  247. Impact of arcing on carbon and tungsten: from the observations in JT-60U, LHD and NAGDIS-II 査読有り

    S.Kajita, M.Fukumoto, M.Tokitani, T.Nakano, Y.Noiri, N.Ohno, S.Masuzaki, S.Takamura, N.Yoshida, Y.Ueda

    Nuclear Fusion   53 巻   頁: 053013(9 pp)   2013年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/53/5/053013

  248. Helium plasma implantation on metals: Nanostructure formation and visible-light photocatalytic response 査読有り

    S.Kajita, T.Yoshida, D.Kitaoka, R.Etoh, M.Yajima, N.Ohno, H.Yoshida, N.Yoshida, Y.Terao

    Journal of Applied Physics   113 巻   頁: 134301(8 pp)   2013年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: doi.org/10.1063/1.4798597

  249. Assessment of multi-pulse laser-induced damage threshold of metallic mirrors for Thomson scattering system 査読有り

    M.Sato, S.Kajita, R.Yasuhara, N.Ohno, M.Tokitani, N.Yoshida, Y.Tawara

    Optics Express   21 巻 ( 8 ) 頁: 9333-9342   2013年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  250. Comparison of damages on tungsten surfac exposed to noble gas plasmas 査読有り

    M.Yajima, M.Yamagiwa, S.Kajita, N.Ohno et al.

    Plasma Science & Technol.   15 巻   頁: 282-286   2013年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  251. Two-dimensional visualization of excitation temperature and chemical species in divertor plasmas: Trace CD molecules by chemical sputtering of fusion plasma reactor wall 査読有り

    Z.Cui, K.Kodama, M.Yamamoto, Q.Shen, M.Yoshimi, S.Kajita, N.Ohno, K.Kitagawa

    Microchemical Journal   106 巻   頁: 174-179   2013年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  252. Influence of the Probe Electrode on Probe Measurements for Atmospheric Pressure Microwave Plasma Torch 査読有り 国際誌

    Ezumi N., Kodama N., Akahane K., Shiozawa S., Sawada K., Ohno N.

    Contributions to Plasma Physics   53 巻 ( 1 ) 頁: 81 - 85   2013年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Contributions to Plasma Physics  

    In this study, in order to clarify the influence of a probe electrode during probe measurements of an atmospheric pressure microwave plasma, simultaneous observations of probe current and the change of plasma shape using a high-speed camera have been done. Fast and random repetitions of attachment and detachment of the plasma torch to the probe electrode have been observed. It is found that the response time is related to ion sound speed. Different behaviors of the plasma torch for a floating metal electrode or an insulator have been observed. Probe current-voltage characteristics show asymmetric double probe shape © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

    DOI: 10.1002/ctpp.201310014

    Scopus

  253. First Principles Investigation on Trapping of Multiple Helium Atoms within a Tungsten Monovacancy 査読有り

    A.Takayama, A.M.Ito, S.Saito, N.Ohno, H.Nakamura

    Japanese Journal of Applied Physics   52 巻   頁: 01AL03(4 pp)   2013年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  254. Deuterium Atomic Density Estimation in Recombining Plasmas Using Self-Absorption Spectroscopy 査読有り

    S.Kajita, T.Nishiwaki, N.Ohno, K.Sawada, M.Takagi

    IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING   8 巻 ( 1 ) 頁: 1-6   2013年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  255. Intermittent transport in edge plasma with a 3-D magnetic geometry in the Large Helical Device 査読有り

    H.Tanaka, S.Masuzaki, N.Ohno, T.Morisaki, Y.Tsuji, the LHD Experiment Group

    Journal of Nuclear Materials   438 巻   頁: S563-S566   2013年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  256. Observation of Arc Spots Initiated on Nanostructured Tungsten 査読有り

    S.Kajita, N.Ohno, S.Takamura

    IEEE TRANSACTIONS ON PLASMA SCIENCE   41 巻 ( 8, Part 2 ) 頁: 1889-1895   2013年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  257. First-Principles Investigation on Trapping of Multiple Helium Atoms within a Tungsten Monovacancy 査読有り

    A.Takayama, A.M.Ito, S.Saito, N.Ohno, H.Nakamura

    Jpn. J. Appl. Phys.   52 巻   頁: 01AL023(4 pp)   2013年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  258. Effect of resistivity profile on current decay time of initial phase of current quench in neon-gas-puff inducing disruptions of JT-60U 査読有り

    S.Kawakami, Y.Shibata, K.Y.Watanabe, N.Ohno, A.Isayama, T.Takizuka, Y.Kawano, M.Okamoto

    Physics of Plasmas   20 巻   頁: 112507(6 pp)   2013年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  259. Extension of operation regimes and investigation of three-dimensional currentless plasmas in the Large Helical Device 査読有り

    O.Kaneko, H.Yamada, S.Inagaki, M.Jakubowski, S.Kajita, et al.(N.Ohno is the 104th author))

    Nucl. Fusion   53 巻   頁: 104015(11 pp)   2013年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  260. Degradation of optical reflectivity of in-vessel mirror materials by helium bombardment 査読有り

    S.Kajita, M.Tokitani, T.Saekim N.Ohno, N.Yoshida

    J. Nucl. Mater.   417 巻   頁: 838-841   2013年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  261. Behavior of Plasma Response Field in Detached Plasma 査読有り 国際誌

    NARUSHIMA Yoshiro, KOBAYASHI Masahiro, AKIYAMA Tsuyoshi, SAKAKIBARA Satoru, MASUZAKI Suguru, ASHIKAWA Naoko, OHNO Noriyasu

    Plasma and Fusion Research   8 巻 ( 0 ) 頁: 1402058 - 1402058   2013年

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:プラズマ・核融合学会  

    Sustaining a detached plasma is important for the reduction of the heat load on a divertor. The externally controlled methods such as gas puffing in the divertor region, etc. have been studied for maintaining detached plasmas. In the recent LHD experiments, a resonant magnetic perturbation (RMP) is utilized to establish the detached plasma, which is one of the candidates to reduce the divertor heat load. The finite plasma response field has been detected when the RMP is imposed, and its behavior is investigated from the viewpoint of the magnetic island dynamics. A parameter of the phase difference, Δ<i>θ</i> (defined as the phase difference between the plasma response field and the RMP), changes from antiphase to in-phase while the plasma transits from the attached to the detached states. Finally, when the Δ<i>θ</i> reaches at certain critical value, Δ<i>θ</i><sub>crit</sub>, the plasma enters the detached state. Since this critical value does not have a dependency on plasma beta and collisionality, Δ<i>θ</i><sub>crit </sub>seems to be a threshold to establish the detached plasma. From the viewpoint of magnetic island dynamics, the behavior of Δ<i>θ</i> approaching in-phase implies the "trend" of island growth. The detached plasma might be established in the case of the tendency for the plasma response field to reinforce the island width.

    DOI: 10.1585/pfr.8.1402058

  262. Thermal radiation characteristics and direct evidence of tungsten cooling on the way to nanostructure formation on its surface 査読有り 国際誌

    Takamura S., Miyamoto T., Ohno N.

    Journal of Nuclear Materials   438 巻 ( SUPPL )   2013年

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Nuclear Materials  

    The physical properties of tungsten with nanostructure on its surface are investigated focusing on the thermal radiation and cooling characteristics. First, direct evidence of substantial W surface cooling has been clearly shown with use of a very thin thermocouple inserted into W target, which solves an uncertainty associated with a radiation thermometer. Second, the above measurements of W surface temperature make it possible to estimate quantitatively the total emissivity from which we may evaluate the radiative power through the Stefan-Boltzmann equation, which is very important for mitigation evaluation of a serious plasma heat load to the plasma-facing component. © 2013 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jnucmat.2013.01.176

    Scopus

  263. Preliminary experiments on the vertical stability with helical coils in a small tokamak, HYBTOK-II 査読有り 国際誌

    Hatakeyama S., Shibata Y., Kawakami S., Tsutsui H., Tsuji-Iio S., Shimada R., Ohno N., Akiyama T., Suzuki Y., Watanabe K.

    39th EPS Conference on Plasma Physics 2012, EPS 2012 and the 16th International Congress on Plasma Physics   1 巻   頁: 285 - 288   2012年12月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:39th EPS Conference on Plasma Physics 2012, EPS 2012 and the 16th International Congress on Plasma Physics  

    In summary, we proposed saddle shaped stellarator system for vertical mode in toka-mak. These preliminary results demonstrate the feasibility of vertical stability, even if only two selected coils which are localized at one side of the torus. However as noted earlier, the experiment were conducted with the circular cross-section tokamak which is stable vertically. Further work is needed to confirm the improvement in the vertical stability in elongated tokamaks. In addition, very large coil current comparable to the plasma current are needed in our system. In order to reduce the current, future work also should focus on optimal configuration of the coils.

    Scopus

  264. Blob/Hole Generation in the Divertor Leg of the Large Helical Device 査読有り

    H.Tanaka, N.Ohno, Y.Tsuji, S.Kajita, S.Masuzaki, M.Kobayashi, T.Morisaki, A.Komori and the LHD Experimental Group

    Plasma and Fusion Research   7 巻   頁: 1402152(6 pp)   2012年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.7.1402152

  265. Fatal Damages due to Breakdown on a Diagnostic Mirror Located outside the Vacuum Vessel in JT-60U 査読有り

    S.Kajita, T.Hatae, T.Sakuma, S.Takamura, N.Ohno, K.Itami

    Plasma and Fusion Research   7 巻   頁: 2405121(4 pages)   2012年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.7.2405121

  266. Optical properties of nanostructured tungsten in near infrared range 査読有り

    S.Kajita, N.Ohno, T.Yokochi, N.Yoshida, R.Yoshihara, S.Takamura, T.Hatae

    Plasma Physics and Controlled Fusion   54 巻   頁: 105015(7 pages)   2012年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0741-3335/54/10/105015

  267. Superimposition of Pulses to Steady Arc Discharge in Toroidal Divertor Simulator 査読有り

    S.Kajita, T.Uchiyama, N.Ohno

    Plasma and Fusion Research   7 巻   頁: 1405100(6 pages)   2012年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.7.1405100

  268. Statistical Analysis of the Spatial Behavior of Plasma Blobs Around the Plasma Column in a Linear Plasma Device 査読有り

    H.Tanaka, N.Ohno, Y.Tsuji, K.Okazaki, S.Kajita

    Contrib. Plasma Phys.   52 巻 ( 5-6 ) 頁: 424 - 428   2012年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/ctpp.201210027

  269. Effect of Externally Applied Resonance Magnetic Perturbation on Current Decay during Tokamak Disruption 査読有り

    Y.Kanazawa, Y.Shibata, M.Okamoto, N.Ohno, S.Kajita

    Plasma and Fusion Research   7 巻   頁: 1202049(2 pages)   2012年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.7.1202049

  270. Effect of neutral pressure on the He plasma flow measurement in a linear device 査読有り 国際共著

    E.-K.Park, H.-J.Woo, K.-S.Chung, H.Tanaka, S.Kajita, N.Ohno

    Current Applied Physics   12 巻   頁: 1479 - 1502   2012年5月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.cap.2012.04.024

  271. Transition in Plasma Fluctuation between Attached and Detached Plasmas 査読有り

    K.Okazaki, H.Tanaka, N.Ohno, S.Kajita

    Plasma and Fusion Research   7 巻   頁: 1201033(2 pages)   2012年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1585/pfr.7.1201033

  272. Arcing on tungsten subjected to helium and transients: ignition conditions and erosion rates 査読有り 国際誌

    Kajita Shin, Ohno Noriyasu, Yoshida Naoaki, Yoshihara Reiko, Takamura Shuichi

    PLASMA PHYSICS AND CONTROLLED FUSION   54 巻 ( 3 )   2012年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0741-3335/54/3/035009

    Web of Science

  273. TEM analysis of high temperature annealed W nanostructure surfaces 査読有り 国際誌

    Kajita Shin, Yoshida Naoaki, Yoshihara Reiko, Ohno Noriyasu, Yokochi Takanori, Tokitani Masayuki, Takamura Shuichi

    JOURNAL OF NUCLEAR MATERIALS   421 巻 ( 1-3 ) 頁: 22 - 27   2012年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2011.11.044

    Web of Science

  274. Anisotropic Graphite Erosion in Low-Temperature and high-Density Deuterium Plasma 査読有り

    M.Teraoka, N.Ohno, S.Kajita, T.Nishiwaki, A.M.Ito, H.Nakamura

    Jpn. J. Appl. Phys.   51 巻   頁: 01AB03 (5pp)   2012年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1143/JJAP.51.01AB03

  275. Near Infrared Radiation from Heated Nanostructured Tungsten 査読有り

    S.Kajita, T.Yokochi, N.Ohno, T.Kumano

    Jpn. J. Appl. Phys.   51 巻   頁: 01AJ03 (5pp)   2012年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1143/JJAP.51.01AJ03

  276. Measurement of ion and electron temperatures in plasma blobs by using an improved ion sensitive probe system and statistical analysis methods 査読有り 国際誌

    K. Okazaki, H. Tanaka, H. Tanaka, N. Ohno, N. Ezumi, Y. Tsuji, S. Kajita

    Review of Scientific Instruments   83 巻   2012年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    We have measured ion temperature as well as electron temperature in plasma blobs observed in a linear plasma device by using an improved ion sensitive probe. Current-voltage characteristics of the ion sensitive probe inside and outside plasma blobs were re-constructed with a conditional sampling method. It is clearly found that both ion and electron temperatures in plasma blobs decrease more slowly in a cross-field direction than those in a bulk plasma without plasma blobs. © 2012 American Institute of Physics.

    DOI: 10.1063/1.3681778

    Scopus

  277. Electric Field at a Plasma-Facing Wall for a Two-Temperature Electron Distribution 査読有り

    Y.Tomita, G.Kawamura, M.Ueno, N.Ohno, Z.H.Huang, Y.D.Pan, L.W.Yan

    Contrib. Plasma Phys.   52 巻 ( 5-6 ) 頁: 484-489   2012年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  278. Thermionic Energy Converter System Using Heat Flux in Divertor Region 査読有り

    D.Oikawa, N.Ohno, S.Kajita, M.Takagi, S.Masuzaki, M.Tokitani, K.Asano

    Plasma and Fusion Research   7 巻   頁: 1405050(8 pages)   2012年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  279. Conditions for the Release of a Metallic Dust Particle from a Plasma-Facing Wall 査読有り

    M.Ueno, N.Ohno, Y.Tomita, G.Kawamura

    Contrib. Plasma Phys.   52 巻 ( 5-6 ) 頁: 478-483   2012年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  280. Effects of fibre-form nanostructures on particle emissions from a tungsten surface in plasmas 査読有り

    S.Takamura, T.Miyamoto, N.Ohno

    Nuclear Fusion   52 巻   頁: 123001(8 pages)   2012年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  281. Validation of the current decay model in the initial phase of current quench in high disruptive discharges of JT-60U 査読有り 国際誌

    Shibata Y., Watanabe K., Ohno N., Okamoto M., Isayama A., Kurihara K., Oyama N., Nakano T., Kawano Y., Sugihara M.

    38th EPS Conference on Plasma Physics 2011, EPS 2011 - Europhysics Conference Abstracts   35 2 巻   頁: 1628 - 1631   2011年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:38th EPS Conference on Plasma Physics 2011, EPS 2011 - Europhysics Conference Abstracts  

    The validation of current decay model during the current quench was investigated in high (3p disruptive discharges on JT-60U. It is experimentally confirmed that the electron temperature does not play an important role in the determination of the current decay time in the initial phase of current quench and that values obtained from L/R model are two orders of magnitude larger than the experimental current decay time. The current decay time predicted by the modified L/R model, in which the time derivative of plasma inductance is taken into account, is in fairly good agreement with the experimental data. In future work, we need to perform the MHD equilibrium code for free-boundary condition such as DINA [5] and TSC [6] code under the axisymmetric assumption in order to clear up the determination mechanism of time derivative of plasma inductance.

    Scopus

  282. Recent progress of tungsten R&amp;D for fusion application in Japan 査読有り 国際誌

    Ueda Y., Lee H.T., Ohno N., Kajita S., Kimura A., Kasada R., Nagasaka T., Hatano Y., Hasegawa A., Kurishita H., Oya Y.

    Physica Scripta T   T145 巻   2011年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physica Scripta T  

    The status of ongoing research projects of tungsten R&D in Japan is summarized in this paper. For tungsten material development, a new improved fabrication technique, the so-called superplasticity-based microstructural modification, is described. This technique successfully improved fracture strength and ductility at room temperature. Recent results on vacuum plasma spray W coating and W brazing on ferritic steels and vanadium alloys are explained. Feasibility of these techniques for the manufacture of the blanket is successfully demonstrated. The latest findings on the effect of neutron damage in tungsten on T retention and on the change in mechanical and electrical properties are described. Retention characteristics for neutron-damaged W were different compared to those for ion-damaged W. Upon neutron irradiation, tungsten alloys containing transmutation elements of W (Re and Os) show changes in properties that are different compared with those shown by pure W. The effects of mixed plasma exposure (D/He/C) are described. Both D/He and D/C mixed ion irradiations significantly affect ion-driven permeation in W. He bubble dynamics play a key role in nano-structure formation on the W surface. © 2011 The Royal Swedish Academy of Sciences.

    DOI: 10.1088/0031-8949/2011/T145/014029

    Scopus

  283. Deuterium retention in Fe <inf>2</inf>O <inf>3</inf> under low-energy deuterium-plasma exposure 査読有り 国際誌

    Matsunami N., Sogawa T., Sakuma Y., Ohno N., Tokitani M., Masuzaki S.

    Physica Scripta T   T145 巻   2011年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physica Scripta T  

    Stainless steel (SUS) is used as the structure material in nuclear fusion devices. Heating and O 2 plasma discharge are considered for the removal of tritium. Oxide layer growth is anticipated on heating SUS at a high temperature in low-pressure residual O 2 gas. When O 2 plasma discharge is performed, oxygen plasma reaches the structure material and iron oxides such as Fe 2O 3 are formed. Thus, a knowledge of the retention behavior of hydrogen isotopes or deuterium (D) in the oxide layers is important in designing the devices. We investigated D retention in Fe 2O 3 films and the influence of Fe 2O 3 crystal structure on D retention and found that D retention in γ-Fe 2O 3 (cubic-maghemite) is larger than that in α-Fe 2O 3 (hexagonal-hematite). The results for Fe 2O 3 are compared with those for SUS and Fe. © 2011 The Royal Swedish Academy of Sciences.

    DOI: 10.1088/0031-8949/2011/T145/014042

    Scopus

  284. TEM observation of the growth process of helium nanobubbles on tungsten: Nanostructure formation mechanism 査読有り 国際誌

    Kajita Shin, Yoshida Naoaki, Yoshihara Reiko, Ohno Noriyasu, Yamagiwa Masato

    JOURNAL OF NUCLEAR MATERIALS   418 巻 ( 1-3 ) 頁: 152 - 158   2011年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2011.06.026

    Web of Science

  285. Helium bubble formation on tungsten in dependence of fabrication method 査読有り 国際誌

    Yamagiwa Masato, Kajita Shin, Ohno Noriyasu, Takagi Makoto, Yoshida Naoaki, Yoshihara Reiko, Sakaguchi Wataru, Kurishita Hiroaki

    JOURNAL OF NUCLEAR MATERIALS   417 巻 ( 1-3 ) 頁: 499 - 503   2011年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2011.02.007

    Web of Science

  286. Nanoscale surface morphology of tungsten materials induced by Be-seeded D-He plasma exposure 査読有り 国際誌

    Tokunaga K., Baldwin M. J., Doerner R. P., Nishijima D., Kurishita H., Fujiwara T., Araki K., Miyamoto Y., Ohno N., Ueda Y.

    JOURNAL OF NUCLEAR MATERIALS   417 巻 ( 1-3 ) 頁: 528 - 532   2011年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2011.01.078

    Web of Science

  287. Exfoliation of the tungsten fibreform nanostructure by unipolar arcing in the LHD divertor plasma 査読有り 国際誌

    Tokitani M., Kajita S., Masuzaki S., Hirahata Y., Ohno N., Tanabe T.

    NUCLEAR FUSION   51 巻 ( 10 )   2011年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/51/10/102001

    Web of Science

  288. Development of Nanostructured Black Metal by Self-Growing Helium Bubbles for Optical Application 査読有り 国際誌

    Kajita Shin, Saeki Tsubasa, Hirahata Yuki, Yajima Miyuki, Ohno Noriyasu, Yoshihara Reiko, Yoshida Naoaki

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 巻 ( 8 ) 頁: 08JG01   2011年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1143/JJAP.50.08JG01

    Web of Science

  289. Investigation on the effect of temperature excursion on the helium defects of tungsten surface by using compact plasma device 査読有り

    S.Takamura, T.Miyamoto, Y.Tomida, T.Minagawa, N.Ohno

    Journal of Nuclear Materials   415 巻   頁: S100-S103   2011年8月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2010.12.021

  290. Exposure of tungsten nano-structure to TEXTOR edge plasma 査読有り 国際共著

    Y.Ueda, K.Miyata, Y.Ohtsuka, H.T.Lee, M.Fukumoto, S.Brezinsek, J.W.Coenen, A.Kreter, A.Litnovsky, V.Philipps, B.Schweer, G.Sergienko, T.Hirai, A.Taguchi, Y.Torikai, K.Sugiyama, T.Tanabe, S.Kajita, N.Ohno, The TEXTOR team

    Journal of Nuclear Materials   415 巻 ( 1 ) 頁: S92 - S95   2011年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2010.08.019

  291. Divertor simulation experiment and its future research plan making use of a large tandem mirror device 査読有り 国際誌

    Nakashima Y., Takeda H., Hosoi K., Yonenaga R., Katanuma I., Ichimura K., Ichimura M., Imai T., Ishii T., Kariya T., Kiwamoto Y., Minami R., Miyata Y., Ozawa H., Shidara H., Yamaguchi Y., Yoshikawa M., Asakura N., Hatayama A., Higashizono Y., Kado S., Masuzaki S., Nishino N., Ohno N., Ueda Y.

    Journal of Nuclear Materials   415 巻 ( 1 SUPPL )   2011年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Nuclear Materials  

    Divertor simulation study has been started as a new research plan, by making best use of a large linear plasma device. The experiment of generating the plasma flow with high heat and particle flux was successfully performed at an end-mirror exit of the GAMMA 10 tandem mirror. In typical hot-ion-mode plasmas, the heat-flux density of 0.6 MW/m2 and the particle-flux density of 1022 particles/s m2 were simultaneously achieved in the case of only ICRF heating and superimposing the 300 kW ECH pulse attained the peak value of the net heat-flux up to 8 MW/m2 on axis. The above experimental results and the simulation analysis of ICRF heating using the Fokker-Planck code give a clear prospect of generating the required performance for divertor studies by building up the plasma heating systems to the end-mirror cell. Detailed behavior of the plasma flow and the future research plan are also described. © 2010 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jnucmat.2010.11.081

    Scopus

  292. Motion of unipolar arc spots ignited on a nanostructured tungsten surface 査読有り

    S.Kajita, S.Takamura, N.Ohno

    Plasma Physics and Controlled Fusion   53 巻 ( 7 ) 頁: 074002   2011年5月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0741-3335/53/7/074002

  293. Molecular Dynamics Simulation of Hydrogen Injection onto Diamond Surfaces 査読有り

    H.Nakamura, A.M.Ito, S.Saito, A.Takayama, Y.Tamura, N.Ohno, S.Kajita

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 巻 ( 1 ) 頁: 01AB04(4 pages)   2011年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1143/JJAP.50.01AB04

  294. Molecular Dynamics Simulation of Chemical Vapor Deposition of Amorphous Carbon: Dependence on H/C Ratio of Source Gas 査読有り

    A.M.Ito, A.Takayama, S.Saito, N.Ohno, S.Kajita, H.Nakamura

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 巻 ( 1 ) 頁: 01AB01(6 pages)   2011年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1143/JJAP.50.01AB01

  295. Formation of Metallic Nanostructure by Helium Plasma Irradiation 査読有り

    Kajita Shin, Saeki Tsubasa, Hirahata Yuki, Ohno Noriyasu

    JAPANESE JOURNAL OF APPLIED PHYSICS   50 巻 ( 1 ) 頁: 01AH02   2011年1月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1143/JJAP.50.01AH02

    Web of Science

  296. Practical selection of emission lines of He I to determine the photon absorption rate 査読有り

    S.Kajita, N.Ohno

    Review of Scientific Instruments   82 巻   頁: 023501(5 pages)   2011年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  297. Formation and decay processes of Ar/He microwave plasma jet at atmospheric gas pressure 査読有り

    S.Takamura, S.Amano, T.Kurata, H.Kasada, J.Yamamoto, M.A.Razzak, G.Kushida, N.Ohno, M.Kando

    Journal of Applied Physics   110 巻   頁: 043301 (8 pages)   2011年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  298. Deuterium retention in Fe2O3 under low-energy deuterium-plasma exposure 査読有り

    N.Matsunami, T.Sogawa, Y.Sakuma, N.Ohno, M.Tokitani, S.Masuzaki

    Physica Scripta   T145 巻   頁: 014042 (4pp)   2011年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  299. In situ measurement of hydrogen isotope retention using a high heat flux plasma generator with ion beam analysis 査読有り

    M.Yamagiwa, Y.Nakamura, N.Matsunami, N.Ohno, S.Kajita, M.Takagi, M.Tokitani, S.Masuzaki, A.Sagara and K.Nishimura

    Physica Scripta   T145 巻   頁: 014032 (5pp)   2011年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  300. Recent progress of tungsten R&D for fusion application in Japan 査読有り

    Y.Ueda, H.T.Lee, N.Ohno, S.Kajita, A.Kimura, R.Kasada, T.Nagasaka, Y.Hatano, A.Hasegawa, H.Kurishita and Y.Oya

    Physica Scripta   T145 巻   頁: 014029 (6pp)   2011年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  301. Beryllium erosion induced by transient heat loads and subsequent reactions in a deuterium plasma 査読有り

    S.Kajita, D.Nishijima, R.Doerner, K.Umstadter, J.Yu, N.Ohno, Y.Ueda

    Journal of Nuclear Materials   420 巻   頁: 252-257   2011年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  302. Study of Plasma Current Decay in the Initial Phase of High Poloidal Beta Disruptions in JT-60U 査読有り 国際誌

    SHIBATA Yoshihide, MATSUNAGA Go, KAMADA Yutaka, SUGIHARA Masayoshi, WATANABE Kiyomasa, OHNO Noriyasu, OKAMOTO Masaaki, ISAYAMA Akihiko, KURIHARA Kenichi, OYAMA Naoyuki, NAKANO Tomohide, KAWANO Yasunori

    Plasma and Fusion Research   ( 6 ) 頁: 1302136 - 1302136   2011年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    In order to validate some current decay models during the current quench, the plasma current decay time was studied using the experimental plasma resistance and inductance in high poloidal beta, &beta;<sub>p</sub>, disruptions in JT-60U. The plasma resistance and inductance were evaluated from an equilibrium calculation code and the measurement value of a magnetic sensor, the electron temperature evaluated by using ECE measurement and the electron density measured by FIR interferometer. In high &beta;<sub>p</sub> disruptions, it was found that the electron temperature at the plasma center just after current quench starts was approximately 1-4 keV under almost the same current decay time observed during the initial phase of current quench. This result indicates that the electron temperature itself plays no major role in the determination of the current decay time in the initial phase of current quench. Moreover, the current decay time predicted by a modified L/R model [Y. Shibata et al., Nucl. Fusion 50, 025015 (2010)], in which the time derivative of plasma inductance was considered, was in good agreement with the experimental current decay time, while the values obtained from the conventional L/R model were two orders of magnitude larger than the experimental results.

    DOI: 10.1585/pfr.6.1302136

  303. Midterm summary of Japan-US fusion cooperation program TITAN 査読有り 国際誌

    Muroga T., Sze D.K., Okuno K., Terai T., Kimura A., Kurtz R.J., Sagara A., Nygren R., Ueda Y., Doerner R.P., Sharpe J.P., Kunugi T., Morley N.B., Hatano Y., Sokolov M.A., Yamamoto T., Hasegawa A., Katoh Y., Ohno N., Tokunaga K., Konishi S., Fukada S., Calderoni P., Yokomine T., Messadek K., Oya Y., Hashimoto N., Hinoki T., Hashizume H., Norimatsu T., Shikama T., Stoller R.E., Tanaka K.A., Tillack M.S.

    Fusion Science and Technology   60 巻 ( 1 ) 頁: 321 - 328   2011年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Fusion Science and Technology  

    Japan-US cooperation program TITAN (Tritium, Irradiation and Thermofluid for America and Nippon) started in April 2007 as 6-year project. This is the summary report at the midterm of the project. Historical overview of the Japan-US cooperation programs and direction of the TITAN project in its second half are presented in addition to the technical highlights.

    DOI: 10.13182/FST11-A12373

    Scopus

  304. Deuterium uptake in iron oxide (Fe<inf>2</inf>O<inf>3</inf>) under D <inf>2</inf><sup>+</sup>-plasma exposure 査読有り 国際誌

    Sogawa T., Matsunami N., Ohno N., Tokitani M., Masuzaki S.

    AIP Conference Proceedings   1321 巻   頁: 274 - 277   2010年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AIP Conference Proceedings  

    We have studied implantation of low-energy deuterium ions into Fe 2O3 films and deuterium (D)-uptake in Fe2O 3 films, which were prepared by oxidation of Fe sheets in air at 400°C for 20 min. X-ray diffraction (XRD) shows that the films are mixture of hexagonal α-Fe2O3 (hematite) and cubic γ-Fe2O3 (maghemite). According to Rutherford backscattering spectroscopy (RBS) of 1.8 MeV H+, the composition is found to be crudely stoichiometric (Fe:O=2:3). The samples were subjected to D2+-plasma exposure using AC-glow discharge. The amount of D-uptake in Fe2O3 is evaluated to be ∼6×10 16cm2 for AC voltage of 1.5 kV in 0.4 Torr of D 2 gas for 15 min. The amount of D-uptake in Fe2O 3 appears to be larger by a factor of three than that in Fe. Comparisons of XRD patterns and RBS spectra before and after D2+-plasma exposure show no appreciable change of the crystalline structure, quality and composition. © 2010 American Institute of Physics.

    DOI: 10.1063/1.3548377

    Scopus

  305. 2D Measurement of Edge Plasma Dynamics by Using High-Speed Camera Based on HeI Line Intensity Ratio Method 査読有り

    Ohno N., Miyamoto K., Kodama K., Kajita S., Kitagawa K.

    CONTRIBUTIONS TO PLASMA PHYSICS   50 巻 ( 10 ) 頁: 962 - 969   2010年11月

  306. Enhancement of cross-field transport into the private region of detached-divertor in Large Helical Device 査読有り

    H. Tanaka, N. Ohno, Y. Tsuji, S. Kajita, S. Masuzaki, M. Kobayashi, T. Morisaki, H. Tsuchiya, A.Komori, and LHD Experimental Group

    Physics of Plasmas   17 巻   頁: 102509(8pages)   2010年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.3496389

  307. Nanostructured Black Metal: Novel Fabrication Method by Use of Self-Growing Helium Bubbles 査読有り

    S.Kajita, T.Saeki, N.Yoshida, N.Ohno, A.Iwamae

    Applied Physics Express   3 巻   頁: 085204-1-3   2010年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1143/APEX.3.085204

  308. 2D Statistical Analysis of Non-Diffusive Transport under Attached and Detached Plasma Conditions of the Linear Divertor Simulator 査読有り

    H.Tanaka, N.Ohno, Y.Tsuji, S.Kajita

    CONTRIBUTIONS TO PLASMA PHYSICS   50 巻 ( 3-5 ) 頁: 256 - 266   2010年5月

  309. Basic Study on the Generation of RF Plasmas in Premixed Oxy-combustion with Methane 査読有り 国際共著 国際誌

    Y.Osaka, N.Kobayashi, M.A.Razzak, N.Ohno, S.Takamura, Y.Uesugi

    Plasma and Fusion Research   ( 5 ) 頁: 010   2010年3月

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    記述言語:英語   出版者・発行元:社団法人 プラズマ・核融合学会  

    Oxy-combustion generates a high temperature field (above 3000 K), which is applied to next generation power plants and high temperature industrial technologies because of N<sub>2</sub> free processes. However, the combustion temperature is so high that the furnace wall may be fatally damaged. In addition, it is very difficult to control the heat flux and chemical species' concentrations because of rapid chemical reactions. We have developed a new method for controlling the flame by electromagnetic force on this field. In this paper, we experimentally investigated the power coupling between the premixed oxy-combustion with methane and radio frequency (RF) power through the induction coil. By optimizing the power coupling, we observed that the flame can absorb RF power up to 1.5 kW. Spectroscopic measurements also showed an increase in the emission intensity from OH radicals in the flame, indicating improved combustibility.

    DOI: 10.1585/pfr.5.010

  310. Study of current decay time during disruption in JT-60U tokamak 査読有り

    Y.Shibata, K.Y.Watanabe, M.Okamoto, N.Ohno, A.Isayama, K.Kurihara, T.Nakano, N.Oyama, Y.Kawano, G.Matsunaga, S.Sakakibara, M.Sugihara, Y.Kamada and the JT-60U team

    Nuclear Fusion   50 巻   頁: 025015 (7pp)   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  311. Formation Condition of Fiberform Nanostructured Tungsten by Helium Plasma Exposure 査読有り

    W. Sakaguchi, S. Kajita, N. Ohno, et al.

    Plasma Fusion Research   5 巻   頁: S1023(5pages)   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  312. Design study of the divertor Thomson scattering system for JT-60SA 査読有り

    S. Kajita, T. Hatae, K. Itami, N. Ohno, T. Nakano

    J. Plasma Fus. Res. Series   9 巻   頁: 157-162   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  313. 2D Measurement of Edge Plasma Dynamics by Using High-Speed Camera Based on HeI Line Intensity Ratio Method 査読有り

    N.Ohno, K.Miyamoto, K.Kodama, S.Kajita, K.Kitagawa

    Contrib. Plasma Physics   50 巻 ( 10 ) 頁: 962-969   2010年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  314. Deepening of Floating Potential for Tungsten Target Plate on the way to Nanostructure Formation 査読有り

    S.Takamura, T.Miyamoto and N.Ohno

    Plasma and Fusion Research: Rapid Communications   5 巻   頁: 039(2 pages)   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  315. Compact Plasma Device for PWI Studies 査読有り

    S.Takamura, T.Tsujikawa, Y.Tomida, K.Suzuki, T.Minagawa, T.Miyamoto, N.Ohno

    J. Plasma Fusion Res. SERIES   9 巻   頁: 441-445   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  316. 2D Statistical Analysis of Non-Diffusive Transport under Attached and Detached Plasma Conditions of the Linear Divertor Simulator 査読有り

    H.Tanaka, N.Ohno, Y.Tsuji, S.Kajita

    Contrib. Plasma Physics   50 巻 ( 3-5 ) 頁: 256-266   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  317. Self-Affine Fractality of Bifurcating Arc Trail in Magnetized Plasma 査読有り

    Shin KAJITA, Noriyasu OHNO, Yoshiyuki TSUJI, Hirohiko TANAKA, and Shuichi TAKAMURA

    Journal of the Physical Society of Japan   79 巻 ( 5 ) 頁: 054501(7 pages)   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  318. Fluid Mechanical Characteristics of Microwave Discharge Jet Plasmas at Atmospheric Gas Pressure 査読有り

    S.Takamura, S.Saito, G.Kushida, M.Kando, N.Ohno,

    IEEJ Trans. FM   130 巻 ( 5 ) 頁: 493-500   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  319. Comparison with Surfaces of Diamond and Graphite for Adsorption of Hydrogen 査読有り

    H.Nakamura, A.Ito, S.Saito, Y.Tamura, S.Fujiwara, N.Ohno, S.Kajita

    Proceedings of ITC19, 2009   1 巻   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  320. Recent progress in understanding the behavior of dust in fusion devices 査読有り

    S.I.Krasheninnikov, A.Yu Pigarov, R.D.Smirnov, M.Rosenberg, Y.Tanka, D.J.Benson, T.K.Soboleva, T.D.Rognlien, D.A.Mendis, B.D.Bray, D.L.Rudakov, J.H.Yu, W.P.West, A.L.Roquemore, C.H.Skinner, J.L.Terry, B.Lipschultz, A.Bader, R.S.Granetz, C.S.Pitcher, N.Ohno, S.Takamura, S.Masuzaki, N.Ashikawa, M.Shiratani, M.Tokitani, R.Kumazawa, N.Asakura, T.Nakano, A.J.Litnovsky, R.Maqueda and the LHD Experimental Group

    Plasma Physics and Controlled Fusion   50 巻 ( 12 ) 頁: 124054(13 pp)   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  321. Degradation of optical reflectivity of in-vessel mirror materials by helium bombardment 査読有り

    S.Kajita, T.Saeki, N.Ohno, M.Tokitani, T.Hatae, W.Sakaguchi

    J. Nuclear Mater.     2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: doi:10.1016/j.jnucmat.2010.12.205

  322. Tungsten blow-off in response to the ignition of arcing: revival of arcing issue in future fusion devices 査読有り

    S.Kajita, S.Takamura, N.Ohno

    J. Nuclear Mater.     2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: doi:10.1016/jjnucmat_2010.08.030.

  323. Comparison of Hydrogen Adsorption on Diamond and Graphite Surfaces 査読有り 国際誌

    NAKAMURA Hiroaki, ITO Atsuhi M., SAITO Seiki, TAMURA Yuichi, FUJIWARA Susumu, OHNO Noriyasu, KAJITA Shin

    Plasma and Fusion Research   ( 5 ) 頁: S2072 - S2072   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    By a classical molecular dynamics (CMD) simulation with a modified Brenner's reactive empirical bond-order (REBO) potential, we found that graphite with zigzag (1010) and armchair (1120) edge states is destroyed more easily than other structures, i.e., graphite with the (0001) surface, and diamond with the (100), (111), (120), and (110) surfaces. Experimental results indicated that graphite is eroded under hydrogen atom injection with E<sub>in</sub> = 0.3 eV, and that diamond is not eroded under the same conditions. Our simulation results are consistent with these experimental results. We also reveal the temperature and saturation dependence of the surface structure of carbon crystals.

    DOI: 10.1585/pfr.5.S2072

  324. Steady-State Operation Scenario and the First Experimental Result on QUEST 査読有り 国際誌

    HANADA Kazuaki, MAEKAWA Takashi, KISHIMOTO Yasuaki, ISHIGURO Masaki, YOSHINAGA Tomokazu, IGAMI Hiroe, NISHINO Nobuhiro, HONMA Hiroshi, KAWASAKI Shoji, NAKASHIMA Hisatoshi, HIGASHIJIMA Aki, SATO Kohnosuke, HIGASHIZONO Yuta, ANDO Akira, ASAKURA Nobuyuki, EJIRI Akira, HIROOKA Yoshihiko, ISHIDA Akio, KOMORI Akio, MATSUKAWA Makoto, MOTOJIMA Osamu, OGAWA Yuichi, ZUSHI Hideki, OHNO Noriyasu, ONO Yasushi, PENG Martin, SUDO Shigeru, YAMADA Hiroshi, YOSHIDA Naoaki, YOSHIDA Zensho, NAKAMURA Kazuo, SAKAMOTO Mizuki, IDEI Hiroshi, HASEGAWA Makoto, TAKASE Yuichi, MITARAI Osamu

    Plasma and Fusion Research   ( 5 ) 頁: S1007 - S1007   2010年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    QUEST focuses on the steady state operation of the spherical tokamak by controlled PWI and electron Bernstein wave current drive. One of the main purposes of QUEST is an achievement of long duration discharge with MW-class injected power. As the result, QUEST should be operated in the challenging region on heat and particle handling. To do the particle handling, high temperature all metal wall up to 623 K and closed divertors are planned, which is to realize the steady-state operation under recycling ratio, R = 1. This is a dispensable check to DEMO, because wall pumping should be avoided as possible in the view of tritium retention. The QUEST project will be developed in increment step such as, I. low &beta; steady state operation in limiter configuration, II. low &beta; steady state operation in divertor configuration, III. relatively high &beta; steady state operation in closed divertor configuration. Phase I in the project corresponds to these two years, and final goal of phase I is to make full current drive plasma up to 20 kA. Closed divertor will be designed and tested in the Phase II. QUEST is running from Oct., 2008 and the first results are introduced.

    DOI: 10.1585/pfr.5.S1007

  325. Formation process of tungsten nanostructure by the exposure to helium plasma under fusion relevant plasma conditions 査読有り

    S.Kajita, W.Sakaguchi, N.Ohno, N.Yoshida, T.Saeki

    Nuclear Fusion   49 巻   頁: 095005(6pp)   2009年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/49/9/095005

  326. Development of Divertor Plasma Simulators with High Heat Flux Plasmas and its Application to Nuclear Fusion Study : A Review 査読有り 国際誌

    OHNO Noriyasu, KAJITA Shin, TAKAGI Makoto, TAKAMURA Shuichi

    IEEJ transactions on electrical and electronic engineering : official journal of the Institute of Electrical Engineering of Japan / = 電気学会   4 巻 ( 4 ) 頁: 476 - 487   2009年7月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  327. Ray tracing simulation for radiation trapping of the He I resonance transition in a linear plasma device 査読有り 国際共著

    S.Kajita, D.Nishijima,E.M.Hollmann, N.Ohno

    Physics of Plasmas   16 巻   頁: 063303   2009年6月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.3157248

  328. Investigation of detached recombining deuterium plasma and carbon chemical erosion in the toroidal divertor simulator NAGDIS-T 査読有り

    K.Yada, N.Matsui, N.Ohno, S.Kajita, S.Takamura, M.Takagi

    Journal of Nuclear Materials   390-391 巻   頁: 290 - 294   2009年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2009.01.123

  329. Spherical cauliflower-like carbon dust formed by interaction between deuterium plasma and graphite target and its internal structure 査読有り 国際誌

    Ohno N., Yoshimi M., Tokitani M., Takamura S., Tokunaga K., Yoshida N.

    JOURNAL OF NUCLEAR MATERIALS   390-91 巻   頁: 61 - 64   2009年6月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2009.01.051

    Web of Science

  330. Deuterium retention in tungsten oxide under low energy D<inf>2</inf><sup>+</sup> plasma exposure 査読有り 国際誌

    Matsunami N., Ohno N., Tokitani M.

    Journal of Nuclear Materials   390-391 巻 ( 1 ) 頁: 693 - 695   2009年6月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Nuclear Materials  

    W is a candidate for plasma facing material and oxide layers are highly anticipated on W surface. We have studied deuterium (D) retention in tungsten oxide (WO3) films and thermal release of deuterium. WO3 films, prepared by oxidation of W metal sheet, were exposed to D2 plasma under AC glow discharge at the applied voltage V up to a few kV and DC discharge. D-retention in W has been studied for comparison. The amount of D retained in the WO3 films and W were analyzed by detecting α particles from the nuclear reaction, D(3He, α)p, using 0.7 MeV 3He+ ions. We find that D-uptake in WO3 film is much larger than in W. According to thermal desorption, release of D2 occurs at ∼180 and 450 °C. © 2009 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.jnucmat.2009.01.191

    Scopus

  331. Erratum: Comparison of He I line intensity ratio method and electrostatic probe for electron density and temperature measurements in NAGDIS-II (Physics of Plasmas (2006) 13 (013301)) 査読有り 国際誌

    Kajita S., Ohno N., Takamura S., Nakano T.

    Physics of Plasmas   16 巻 ( 2 )   2009年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physics of Plasmas  

    DOI: 10.1063/1.3076930

    Scopus

  332. Prompt ignition of a unipolar arc on helium irradiated tungsten 査読有り

    S.Kajita, S.Takamura and N.Ohno

    Nuclear Fusion   49 巻   頁: 032002(4pp)   2009年2月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/49/3/032002

  333. Development of Divertor Plasma Simulators with High Heat Flux Plasmas and Its Application to Nuclear Fusion Study 査読有り

    大野 哲靖

    IEEJ Transactions 4     頁: 476 - 487   2009年

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  334. Visualized blow-off from helium irradiated tungsten in response to ELM-like heat load 査読有り

    S.Kajita, N.Ohno, W.Sakaguchi, M.Takagi

    Plasma and Fusion Research   4 巻   頁: 004(6 pages)   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  335. In situ reflectivity of tungsten mirrors under helium plasma exposure 査読有り

    W.Sakaguchi, S.Kajita, N.Ohno, M.Takagi

    Journal of Nuclear Materials     頁: doi:10.1016/j.jnucmat.2009.01.276   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  336. *Development of Divertor Plasma Simulators with High Heat Flux Plasmas and its Application to Nuclear Fusion Study: A Review 査読有り

    N.Ohno, S.Kajita, M.Takagi, S.Takamura

    TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING IEEJ Trans.   4 巻   頁: 476,487   2009年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  337. Formation and mitigation of fiberform nanostructured tungsten by helium and sub-ms laser pulse irradiations 査読有り

    S.Kajita, W.Sakaguchi and N.Ohno

    Plasma Devices and Operations   17 巻   頁: 165,173   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  338. Statistical analysis of fluctuation characteristics at high- and low-field sides in L-mode SOL plasmas of JT-60U 査読有り

    H.Tanaka, N.Ohno, N.Asakura, Y.Tsuji, H.Kawashima, S.Takamura, Y.Uesugi and the JT-60U Team

    Nuclear Fusion   49 巻   頁: 65017   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  339. *Spherical cauliflower-like carbon dust formed by interaction between deuterium plasma and graphite target and its internal structure 査読有り

    N.Ohno, M.Yoshimi, M.Tokitani, S.Takamura, K.TOkunaga, N.Yoshida

    Journal of Nuclear Materials     頁: doi:10.1016/j.jnucmat.2009.01.051   2009年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  340. High temperature irradiation damage of carbon materials studies by laser Raman spectroscopy 査読有り

    M.Yoshida, T.Tanabe, N.Ohno, M.Yoshimi, S.Takamura

    Journal of Nuclear Materials   386-388 巻   頁: 841-843   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  341. Statistical analysis to the SOL plasma fluctuation in JT-60U 査読有り

    N. Asakura, N. Ohno, H. Tanaka, H. Kawashima, T. Nakano

    J.Nucl. Mater.   390-391 巻   頁: 364-367   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  342. Effects of tungsten surface conditions on carbon deposition 査読有り

    Y. Ueda, M. Fukumoto, A. Yamawaki, Y. Soga, Y. Ohtsuka, S. Brezinsek, T. Hirai, A. Kirschner, A. Kreter, A. Litnovsky, V. Philipps, A. Pospieszczyk, B. Schweer, G. Sergienko, T. Tanabe, K. Sugiyama, K. Ohya, N. Ohno and The TEXTOR team

    J.Nucl. Mater.   390-391 巻   頁: 44-48   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  343. Deuterium retention in Tungsten Oxyside under low-voltage D2+ plasma exposure 査読有り

    N.Matsunami, N.Ohno and M.Tokitani

    J.Nucl. Mater.   390-391 巻   頁: 693-695   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  344. Development of net-current free heliotron plasmas in the Large Helical Device 査読有り

    A.Komori, H.Yamada, S.Sakakibara, O.Kaneko, K.Kawahata, T.Mutoh, N.Ohyabu, S.Imagawa, K.Ida, Y.Nagayama, T.Shimozuma, K.Y.Watanabe, T.Mito, M.Kobayashi, K.Nagaoka, R.Sakamoto, N.Yoshida, S.Ohdachi, N.Ashikawa, Y.Feng, T.Fukuda, H.Igami, S.Inagaki, H.Kasahara, S.Kubo, R.Kumazawa, O.Mitarai, S.Murakami, Y.Nakamura, M.Nishiura, T.Hino, S.Masuzaki, K.Tanaka, K.Toi, A.Weller, M.Yoshinuma, Y.Narushima, N.Ohno, T.Okamura, N.Tamura, K.Saito, T.Seki, S.Sudo, H.Tanaka, T.Tokuzawa, N.Yanagi, M.Yokoyama, Y.Yoshimura, T.Akiyama, H.Chikaraishi, M.Chowdhuri, M.Emoto, N.Ezumi, H.Funaba, L.Garcia, P.Goncharov, M.Goto, K.Ichiguchi, M.Ichimura, H.Idei, T.Ido, S.Iio, K.Ikeda, M.Irie, A.Isayama, T.Ishigooka, M.Isobe, T.Ito, K.Ito, A.Iwamae, S.Hamaguchi, T.Hamajima, S.Kitajima, S.Kado, D.Kato, T.Kato, S.Kobayashi, K.Kondo, S.Masamune, Y.Matsumoto, N.Matunami, T.Minami, C.Michael, H.Miura, J.Miyazaa, N.Mizuguchi, T.Morisaki, S.Morita, G.Motojima, I.Murakami, S.Muto, K.Nagasaki, N.Nakajima, Y.Nakamura, H.Nakanishi, H.Nakano, K.Narihara, A.Nishimura, H.Nishimura, K.Nishimura, S.Nishimura, N.Nishino, T.Notake, T.Obana, K.Ogawa, Y.Oka, T.Ohishi, H.Okada, K.Okuno, K.Ono, M.Osakabe, T.Osako, T.Ozaki, B.J.Peterson, H.Sakaue, M.Sasao, S.Satake, K.Sato, M.Sato, A.Shimizu, M.Shiratani, M.Shoji, H.Sugama, C.Suzuki, Y.Suzuki, K.Takahata, H.Takahashi, Y.Takase, Y.Takeiri, H.Takenaga, S.Toda, Y.Toda, M.Tokitani, H.Tsuchiya, K.Tsumori, H.Urano, E.Veshchev, F.Watanabe, T.Watanabe, T.H.Watanabe, I.Yamada, S.Yamada, O.Yamagishi, S.Yamaguchi, S.Yoshimura, T.Yoshinaga and O.Motojima

    Nuclear Fusion   49 巻   頁: 104015(8pp)   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  345. Direct observation of cathode spot grouping using nanostructured electrode 査読有り

    S.Kajita, N.Ohno, S.Takamura, Y.Tsuji

    Physics Letters A   373 巻   頁: 4273-4277   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  346. Discharge Bifurcation of Microwave-sustained Helium Plasma Torch at Atmospheric Pressure 査読有り

    S.Takamura, M.Kando, N.Ohno

    J.Plasma Fusion Res. SERIES   8 巻   頁: 910-913   2009年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  347. Statistical properties of edge plasma turbulence in the Mega-Amp Spherical Tokamak and the Large Helical Device 査読有り 国際共著 国際誌

    Dewhurst J., Hnat B., Ohno N., Dendy R., Masuzaki S., Morisaki T., Komori A., Dudson B., Counsell G., Kirk A.

    35th EPS Conference on Plasma Physics 2008, EPS 2008 - Europhysics Conference Abstracts   32 巻 ( 2 ) 頁: 898 - 901   2008年12月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:35th EPS Conference on Plasma Physics 2008, EPS 2008 - Europhysics Conference Abstracts  

    Scopus

  348. Deuterium retention near surface of TiO<inf>2</inf> by low-voltage D <inf>2</inf> plasma discharge 査読有り 国際誌

    Matsunami N., Tanaka T., Ohno N., Tokitani M.

    Physica Status Solidi (C) Current Topics in Solid State Physics   5 巻 ( 4 ) 頁: 923 - 926   2008年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physica Status Solidi (C) Current Topics in Solid State Physics  

    We have investigated deuterium (D) uptake in TiO2 (rutile) films under exposure of low-energy D2+ ions and thermal release of D from TiO2 films. The amount of deuterium in the films was analysed by means of nuclear reaction analysis, D(3He, α)p. D-uptake under AC-glow discharge in D2 pressure of ∼90 Pa is compared with that under DC-discharge with well-defined energy of D 2+ ions in D2 pressure of ∼0.1 Pa. The results imply that the effective energy of D2+ ions in AC-glow discharge is much lower than the energy derived from the applied voltage. The results are also compared with those for Ti sheet exposed to low-energy D2+ ions. We find that D-release temperature from TiO2 is considerably lower than from Ti, though D-uptake in TiO2 is smaller than in Ti. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.

    DOI: 10.1002/pssc.200778343

    Scopus

  349. 11<sup>th</sup> International Workshop on Plasma Edge Theory in Fusion Devices: Preface 査読有り 国際共著 国際誌

    Heikkinen J., Ohno N.

    Contributions to Plasma Physics   48 巻 ( 1-3 )   2008年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Contributions to Plasma Physics  

    DOI: 10.1002/ctpp.200890000

    Scopus

  350. Intermittency and extended self-similarity in space and fusion plasma: boundary effects 査読有り

    V.P.Budaev, S.Savin, L.Zelencyi, N.Ohno, S.Takamura and E.Amata

    Plasma Physics and Controlled Fusion   50 巻   頁: 074014(20pp)   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  351. Measurement of Plasma Properties of the Atmospheric Oxy-Combustion Flame by Using Double Probe Method 査読有り

    Y.Osaka, N.Kobayashi, N.Ohno, S.Takamura, Y.Tanaka, Y.Uesugi

    Contrib. Plasma Physics   48 巻 ( 5-7 ) 頁: 485-490   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  352. Extended self-similarity of intermittent turbulencein edge magnetized plasmas 査読有り

    V.P. Budaev, N. Ohno, S.Takamura, S. Masuzaki, A. Komori, T. Morisaki

    Nuclear Fusion   48 巻   頁: 24014   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  353. Deuterium retention near surface of TiO2 by low-voltage D2 plasma discharge 査読有り

    N.Matsunami, T.Tanaka, N.Ohno and M.Tokitani

    Phys. Stat. Sol.(c)   5 巻 ( 4 ) 頁: 923-926   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  354. ELM propagation in the low- and high- filed-side Scrape-off Layer of the JT-60U tokamak 査読有り

    N.Asakura, H.Kawashima, N.Ohno, G.Matsunaga, T.Nakano and N.Oyama

    Journal of Physics; Conference Series   123 巻   頁: 012009(11pp)   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  355. Statistical properties of edge plasma turbulence in the Large Helical Device 査読有り

    J.M.Dewhurst, B.Hnat, N.Ohno, R.O.Dendy, S.Masuzaki, T.Morisaki and A.Komori

    Plasma Physics and Controlled Fusion   50 巻   頁: 095013(15pp)   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  356. Fluctuating Helium Emission in Optically Thick Divertor Plasmas 査読有り

    F. B. Rosmej, N. Ohno, S. Takamura, S. Kajita

    Contributions to Plasma Physics   48 巻   頁: 243-248   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  357. Numerical Modeling of Behavior of Dust Made of Different Materials in Plasmas 査読有り

    Y. Tanaka, A. Yu. Pigarov, R. D. Smirnov, S. I. Krasheninnikov, N. Ohno, Y. Uesugi

    Contributions to Plasma Physics   48 巻   頁: 295-299   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  358. Extended Self-Similarity in Edge Plasma Turbulence of Fusion Devices 査読有り

    V. P. Budaev, N. Ohno, S. Takamura, S. Masuzaki, A. Komori, T. Morisaki

    Contributions to Plasma Physics   48 巻   頁: 42-47   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  359. Plasma Rotation Measurements by Passive Spectroscopic Method in the HYBTOK-II using a Dynamic Ergodic Divertor 査読有り

    Y.Hasebe, M.Okamoto, S.Kajita, N.Ohno and S.Takamura

    Plasma and Fusion Research   3 巻   頁: S1015   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  360. ELM propagation in the low- and high-field-side scrape-off layer of the JT-60U tokamak 査読有り 国際誌

    Asakura N., Kawashima H., Ohno N., Matsunaga G., Nakano T., Oyama N.

    Journal of Physics: Conference Series   123 巻   2008年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Physics: Conference Series  

    In JT-60U, the filament structure of Edge Localized Modes (ELMs) is measured at three poloidal locations, and their temporal evolution is investigated at the inner (high magnetic-field-side, HFS) SOL as well as outer (low magnetic-field-side, LFS) SOL. At the inner SOL, filament structure with 7-8 temporal multi-peaks in ion-saturation probe signals and other diagnostics is, for the first time, measured close to the sepatratrix. The delay of the first peak after the start of MHD activity is faster than the characteristic time of the parallel convection from the outer midplane, and the Mach numbers of the plasma parallel flow reach ion sonic levels. These results show that ELM filaments extend from the outer to the inner plasma edge, and that a part of the filaments are ejected into the inner SOL. The toroidal mode numbers (n) and poloidal width of the filaments (δz) are evaluated from the interval of the multi-peaks and duration of each peak, yielding n ∼ 18-44 and δz ∼ 2-6 cm on the HFS SOL, while n and δz are comparable on the LFS SOL. After the multi-peaks appear, flow reversal of the SOL plasma toward is observed over a wide region of the inner SOL. © 2008 IOP Publishing Ltd.

    DOI: 10.1088/1742-6596/123/1/012009

    Scopus

  361. Plasma-assisted laser ablation of tungsten: Reduction in ablation power threshold due to bursting of holes/bubbles 査読有り 国際誌

    Kajita S., Ohno N., Takamura S., Sakaguchi W., Nishijima D.

    Applied Physics Letters   91 巻 ( 26 )   2007年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Applied Physics Letters  

    Nanosecond laser ablation of tungsten (W) exposed to helium plasma is investigated using optical emission spectroscopy. Submicrometer-sized holes/bubbles are formed on the surface of W when it was exposed to the helium plasma at a sufficiently high temperature (1500-1600 K). The emissions from a virgin W (before the helium plasma irradiation) cannot be detected when the fluence is <1 J cm2; however, the threshold fluence for the detection of neutral W emission after it was exposed to the helium plasma is ∼0.2 J cm2. The physical mechanism of laser-induced bursting of holes/bubbles is proposed for achieving a significant reduction in ablation power threshold. © 2007 American Institute of Physics.

    DOI: 10.1063/1.2824873

    Scopus

  362. Effect of cross-field transport on H<sup>-</sup> density profile in magnetized plasmas: Comparison between measurement and simulation 査読有り 国際誌

    Kajita S., Kado S., Ohno N., Takamura S., Kurihara K., Kuwahara Y.

    Physics of Plasmas   14 巻 ( 10 )   2007年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physics of Plasmas  

    The radial density profile of negative hydrogen ions in magnetized plasma is investigated in the divertor simulator MAP (Material and plasma)-II [S. Kado et al., J. Plasma Fusion Res. 71, 810 (2005)] by measurement and numerical simulation. The laser photodetachment method is used to evaluate the H - density by considering the influence of the magnetic field. The density of H- has a hollow profile and exhibits a peak in the peripheral region, though the electron density and temperature exhibit a peak at the center of the plasma column. The density profile of H- does not agree with the calculation result obtained from, the rate equation, in which the local production and extinction rates are balanced, under the present experimental condition. To understand the behavior of negative ions, their trajectories are calculated by numerically solving the equation of motion by considering the effect of collisions. The negative ion density profile calculated from the particle simulation agrees well with the measured negative ion density profile. It is shown that the cross-field H- transport due to the radial electric field with the assistance of the elastic collisions plays an important role in enhancing the negative ion density in the peripheral region. © 2007 American Institute of Physics.

    DOI: 10.1063/1.2789559

    Scopus

  363. Sub-ms Laser Pulse Irradiation on Tungsten Target Damaged by Exposure to Helium Plasma 査読有り

    S.Kajita, S.Takamura, N.Ohno, D.Nishijima, H.Iwakiri, N.Yoshida

    Nuclear Fusion   47 巻   頁: 1358 - 1366   2007年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/47/9/038

  364. Integrated view of disruption dynamics on internal electromagnetic and plasma structures in the small tokamak HYBTOK-II 査読有り

    M. Okamoto, S. Takamura, N. Ohno, S. Kajita, Y. Kikuchi, Y. Uesugi, T. Ozeki, Y. Kawano, M. Sugihara

    Nuclear Fusion   47 巻   頁: 1106 - 1111   2007年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/0029-5515/47/9/006

  365. Surface modification at tungsten and tungsten coated graphite due to low energy and high fluence plasma and laser pulse irradiation 査読有り 国際誌

    Ohno N., Kajita S., Nishijima Dai, Takamura S.

    JOURNAL OF NUCLEAR MATERIALS   363 巻   頁: 1153 - 1159   2007年6月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2007.01.148

    Web of Science

  366. Modeling of Dust-particle Behavior for Different Materials in Plasmas 査読有り

    Y.Tanaka, A.Yu.Pigarov, R.D.Smirnov, S.I.Krasheninnikov, N.Ohno, Y.Uesugi

    Physics of Plasmas   14 巻   頁: 52504   2007年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.2722274

  367. High density plasma generation by RF ohmic discharge in toroidal divertor simulator NAGDIS-T 査読有り

    M. Nagase, H. Masuda, N. Ohno, S. Takamura and M. Takagi

    Journal of Nuclear Materials   363-365 巻   頁: 611-615   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  368. Systematic Analysis of Current Decay Time during Disruption in HYBTOK-II Tokamak 査読有り

    M.Okamoto, N.Ohno, S.Takamura

    Plasma and Fusion Research   3 巻   頁: 6   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  369. Effect of Cross-field Transport on H-Density Profile in Magnetized Plasmas: Comparison Between Measurement and Simulation 査読有り

    S.Kajita, S.Kado, N.Ohno, K.Kurihara, Y.Kuwahara, S.Takamura

    Physics of Plasmas   14 巻   頁: 103503   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  370. Plasma-assisted Laser Ablaion of Tungsten: Reduction in Ablation Power Threshold Due to Bursting of Holes/Bubbles 査読有り

    S.Kajita, N.Ohno, S.Takamura, W.Sakaguchi, D.Nishijima

    Applied Physics Letters   9191 巻   頁: 261501   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  371. Development of Tungsten Materials for Plasma Facing Components in Japan 査読有り

    Y.Ueda, N.Ohno, S.Kajita, H.Kurishita, H.Iwakiri et al

    Fusion Science and Technology   52 巻   頁: 513-520   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  372. Overview of JT-60U results for the Development of a Steady-state Advanced Tokamak Scenario 査読有り

    H.Takenaga, the JT-60 Team

    Nuclear Fusion   47 巻   頁: S563-S578   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  373. Structural Bifurcation of Microwave Helium Jet Discharge at Atmospheric Pressure 査読有り

    S.TAKAMURA, M.KITOH, T.SOGA, H.TAKASHIMA, Y.NISHINO, S.HAYAKAWA, Y.BAN, T.YUHKI, M.KANDO, N.OHNO

    Plasma and Fusion Research   3 巻   頁: 12   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  374. Alleviation of Damaged Tungsten Having Helium Holes/Bubbles by Use of Transient Heat Load 査読有り

    S.Kajita, S.Takamura, N.Ohno, T.Nishimoto

    Plasma Fusion Research   2 巻   頁: 9   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  375. Extended Steady-state and High-beta Regimes of Net-current Free Heliotron Plasmas in the Large Helical Device 査読有り

    O.Motojima, H.Yamada, A.Komori, N.Ohyabu, T.Mutoh, O.Kaneko, K.Kawahata, T.Mito, K.Ida, S.Imagawa, Y.Nagayama, T.Shimozuma, K.Y.Watanabe, S.Masuzaki, J.Miyazawa, T.Morisaki, S.Morita, S.Ohdachi, N.Ohno, K.Saito, S.Sakakibara, Y.Takeiri, N.Tamura, K.Toi, M.Tokitani, M.Yokoyama, M.Yoshinuma, K.Ikeda, A.Isayama, K.Ishii S.Kubo, S.Murakami, K.Nagasaki, T.Sekim K.Takahata, H.Takenaga and the LHD Experimental Group

    Nuclear Fusion   47 巻   頁: S668-S676   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  376. Plasma-surface Interaction, Scrape-off Layer and Divertor Physics: Implications for ITER 査読有り

    B.Lipschultz, X.Bonnin, G.Counsell, A.Kallenbach, A.Kukushkin, K.Krieger, A.Leonard, A.Loarte, .Neu, R.A.Pitts, T.Rognlien, J.Roth, C.Skinner, J.L.Terry, E.Tsitrone, D.Whyte, S.Zweben, N.Asakura, D.Coster, R.Doerner, R.Dux, G.hendrih, A.Herrmann, J.Hu, S.Krasheninnikov, G.Kirnev, A.Kreter, V.Kurnaev, B.LaBombard, S.Lisgo, T.Nakano, N.Ohno, H.D.Pacher, J.Paley, Y.Pan, G.Pautasso, V.Philipps, V.Rohde, D.Rudakov, P.Stangeby, S.Takamura, T.Tanabe, Y.Yang, S.Zhu

    Nuclear Fusion   47 巻   頁: 1189-1205   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  377. High Density Plasma Generation by RF Ohmic Discharge in Toroidal Divertor Simulator NAGDIS-T 査読有り

    M.Nagase, H.Masuda, N.Ohno, S.Takamura, M.Takagi

    J. Nucl. Mater.   363-365 巻   頁: 611-615   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  378. Dynamic Interaction between Disruptive Plasma and Wall in the Small Tokamak HYBTOK-II 査読有り

    M.Okamoto, T.Yamada, T.Hiraishi, Y.Kikuchi, N.Ohno, S.Takamura

    J. Nucl. Mater.   363-365 巻   頁: 1076-1080   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  379. Alleviation of Helium Holes/Bubbles on Tungsten Surface by Use of Transient Heat Load 査読有り 国際誌

    KAJITA Shin, TAKAMURA Shuichi, OHNO Noriyasu, NISHIMOTO Tentaro

    Plasma and Fusion Research   ( 2 ) 頁: 9 - 9   2007年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    The alleviation effect of transient heat load on helium holes/bubbles has been demonstrated using ruby laser pulses for the transient heat source in the divertor simulator NAGDIS-II. It is shown that the holes and bubbles disappeared following the irradiation of the ruby laser pulses, while the surface roughness was significantly enhanced by the irradiation of the Nd:YAG laser pulses. Based on the numerically calculated temperature in the specimen, the physical mechanism causing this difference is discussed particularly in terms of pulse width (0.6 ms for ruby laser without a Q-switch and 5 ns for Nd:YAG laser with a Q-switch).

    DOI: 10.1585/pfr.2.009

  380. Plasma response on penetration of external rotating helical magnetic field in HYBTOK-II tokamak edge plasma 査読有り 国際誌

    Budaev V.P., Pankratov I.M., Takamura S., Ohno N., Kajita S., Takagi M., Matsuno H., Okamoto M., Hosoi S., Hasebe Y., Yamada T., Omelchenko A.Y., Olshansky V.V.

    33rd EPS Conference on Plasma Physics 2006, EPS 2006   2 巻   頁: 1548 - 1551   2006年12月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:33rd EPS Conference on Plasma Physics 2006, EPS 2006  

    Scopus

  381. Intermittency in laboratory and space plasmas: Comparative study of multifractal statistics 査読有り 国際共著 国際誌

    Budaev V., Savin S., Zelenyi L., Takamura S., Ohno N., Shevyrev N.

    33rd EPS Conference on Plasma Physics 2006, EPS 2006   1 巻   頁: 344 - 347   2006年12月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:33rd EPS Conference on Plasma Physics 2006, EPS 2006  

    Scopus

  382. Reduction of laser power threshold for melting tungsten due to subsurface helium holes 査読有り 国際誌

    Kajita Shin, Nishijima Dai, Ohno Noriyasu, Takamura Shuichi

    JOURNAL OF APPLIED PHYSICS   100 巻 ( 10 )   2006年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.2387151

    Web of Science

  383. Modification of the damping rate of the oscillations of a dust particle levitating in a plasma due to the delayed charging effect 査読有り 国際共著 国際誌

    Pustylnik M.Y., Ohno N., Takamura S., Smirnov R.

    Physical Review E - Statistical, Nonlinear, and Soft Matter Physics   74 巻 ( 4 )   2006年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physical Review E - Statistical, Nonlinear, and Soft Matter Physics  

    Dependence of the damping rate of the oscillations of the dust particles levitating in the sheath on the plasma parameters is investigated both theoretically and experimentally. Significant deviations of the damping rate from the values predicted by the Epstein formula are found in the experiment. The delayed charging effect is applied for the theoretical explanation of the experimental results. Qualitative agreement between the theoretical and experimental data is obtained. © 2006 The American Physical Society.

    DOI: 10.1103/PhysRevE.74.046402

    Scopus

  384. Superdiffusion and multifractal statistics of edge plasma turbulence in fusion devices 査読有り 国際共著 国際誌

    Budaev V.P., Takamura S., Ohno N., Masuzaki S.

    Nuclear Fusion   46 巻 ( 4 )   2006年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    The edge plasma turbulence in the T-10 tokamak, the HYBTOK-II tokamak, the linear machine NAGDIS-II and the Large Helical Device have been studied. The fluctuations in the plasma density have been analysed in terms of the multifractal formalism revisited with wavelets. In most of the cases considered, the edge density fluctuations demonstrate multifractal statistics, i.e. the scaling behaviour of the absolute moments is described by a convex function with non-trivial self-similarity properties. The multifractality factor defined in the multiplicative cascade model is a relevant parameter for characterizing the edge plasma turbulence. The multiplicative cascade process has a 'coarse' time scale T ∼ 50-200 ms iterating towards finer scales. This time scale is referred to as an integral correlation scale. The self-similarity parameters have been observed to depend on the edge plasma condition. The correlation and transport properties have been analysed regarding the multifractality parameter. The diffusion transport coefficient in an edge plasma is not a trivial function of multifractality parameters. © 2006 IAEA, Vienna.

    DOI: 10.1088/0029-5515/46/4/S10

    Scopus

  385. Comparison of HeI Line Intensity Ratio Method and Electrostatic Probe for Electron Density and Temperature Measurements in NAGDIS-II 査読有り

    S.Kajita, N.Ohno, S.Takamura, T.Nakano

    Physics of Plasmas   13 巻   頁: 013301(9pages)   2006年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.2164461

  386. Fundamental study on the control of oxy-combustion by rf non-equilibrium plasma 査読有り

    Y.Osaka, N.Kobayashi, M.A.Razzak, N.Ohno, S.Takamura

    Fluid and heat engineering research   41 巻   頁: 5-12   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  387. Formation of Nanostructured Tungsten with Arborescent Shape due to Helium Plasma Irradiation 査読有り

    S.Takamura, N.Ohno, D.Nishijima, S.Kajita

    Plasma Fusion Res.   1 巻   頁: 051(2pages)   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  388. Reduction of Laser Threshold for Melting Tungsten due to Subsurface Helium Holes 査読有り

    S.Kajita, D.Nishijima, N.Ohno, S.Takamura

    J. Appl. Phys.   100 巻   頁: 103304(10 pages)   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  389. Modification of the Damping Rate of the Oscillation of a Dust Particle levitating in a Plasma Due to the Delayed Charging Effect 査読有り

    M.Y.Pustylnik, N.Ohno, S.Takamura, R.Smirnov

    Phys. Rev. E   74 巻   頁: 046402(9pages)   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  390. Analysis on Relation between Magnetic Structure and Bursty Fluctuation in SOL/Divertor Plasma of LHD 査読有り

    N.Ohno, S.Masuzaki, H.Miyoshi, S.Takamura, V.P.Budaev, T.Morisaki, N.Ohyabu, A.Komori

    Contrib. Plasma Physics   46 巻   頁: 692-697   2006年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  391. Numerical Analysis on Generation of High Density Plasmas in the Toroidal Device NAGDIS-T for SOL and Divertor Simulation Studies 査読有り

    M.Nagase, S.Takamura, N.Ohno, H.Masuda, H.Kitahara, M.Takagi

    Contrib. Plasma Physics   46 巻   頁: 557-562   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  392. Carbon Dust Formation and Chemical Erosion Process in High Density Deuterium Plasmas in the Linear Divertor Simulator

    Y.Miyachi, M.Yoshimi, N.Ohno, S.Takamura

    17th PSI Conference, Heifei, China, May 22-26, 2006     頁: 2-50   2006年

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    記述言語:英語  

  393. Charactersitics of rf inductive plasma in oxy-combustion

    Yugo Osaka, Noriyuki Kobayashi, M.A.Razzak, Noriyasu Ohno, Shuichi Takamura

    The 4th International Conference on Combustion, Incineration/Pyrolysis and Emission Control, September 26-29, 2006, Kyoto, Japan   1 巻   2006年

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    記述言語:英語  

  394. Fundamental research on plasma-assisted combustion by applying rf power

    Yugo Osaka, Noriyuki Kobayashi, M.A.Razzak, Noriyasu Ohno, Shuichi Takamura

    11th Asian Pacific Confederation of Chemical Engineering Congress, August 27-30, 2006 Kuala Lumpur, Malaysia   1 巻   2006年

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    記述言語:英語  

  395. Dust Formation and Transport in the Divertor Plasma Simulators

    N.Ohno, M.Miyoshi, T.Yamada, M.Pustylnik, S.Kajita, S.Takamura

    7th Workshop ont Fine Particle Plasma, NIFS, oki, Japan December, 15-16, 2006(招待講演)   1 巻   2006年

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    担当区分:筆頭著者   記述言語:英語  

  396. Two-dimensional measurement of plasma dynamics with an ICCD fast camera based on HeI line intensity ratio method

    N.Yamamoto, K.Miyamoto, K.Kitagawa, S.Kajita, M.Okamoto, N.Ohno

    16th International Toki Conference on Advanced Imaging and Plasma Diagnostics, Toki, Gifu, Japan, Dec. 5-8, 2006     頁: 6-15   2006年

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    記述言語:英語  

  397. Imaging of tungsten impurity ejected from damaged material due to transient heat load

    S.Kajita, N.Ohno, S.Takamura

    16th International Toki Conference on Advanced Imaging and Plasma Diagnostics, Toki, Gifu, Japan, Dec. 5-8, 2006     頁: 4-01   2006年

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    記述言語:英語  

  398. ELM Propagation and Fluctuations Characteristics in H- and L-mode SOL Plasmas on JT-60U

    N.Asakura, N.Ohno, H.Kawashima, H.Miyoshi, G.Matsunaga, N.Oyama, S.Takamura, Y.Uesugi, M.Takechi, T.Nakano, H.Kubo

    21st IAEA Fusion Energy Conference, Chengdu, China, Oct. 16-21, 2006     頁: EX/9-2   2006年

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    記述言語:英語  

  399. Integrated View of Disruption Dynamics on Internal Electromagnetic and Plasma Structures in the small tokamak HYBTOK-II

    M.Okamoto, S.Takamura,N.Ohno, S.Kajita, Y.Kikuchi, Y.Uesugi, T.Ozeki, Y.Kawano, M.Sugihara

    21st IAEA Fusion Energy Conference, Chengdu, China, Oct.16-21,2006     頁: EX/P8-14   2006年

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    記述言語:英語  

  400. Super Dense Core Plasma due to Internal Diffusion Barrier in LHD

    N.Ohyabu, .Morisaki, S.Masuzaki, R.Sakamoto, M.Kobayashi, J.Miyazawa, M.SHoji, T.Akiyama, N.Ashikawa, M.Emoto, H.Funaba, P.Goncharov, M.Goto, J.H.Harris, Y.Hirooka, K.Ichiguchi, T.Ido, K.Itoh, H.Igami, K.Ikeda, S.Inagaki, H.KAsahara, T.Kobuchi, S.Kubo, R.Kumazawa, S.Morita, S.Muto, K.Nagaoka, N.Nakajima, Y.Nakamura, H.Nakanishi, K.Nariharam Y.Narushima, M.Nishiura, T.Notake, S.Ohdachi, N.Ohno, Y.Oka, M.Osakabe, T.Ozaki, B.J.Peterson, K.Saito, S.Sakakibara, R.Sanchez, H.Sanuki, K.Sato, T.Seki, A.SHimizu, H.SUgama, C.Suzuki, Y.Suzuki, Y.Takeiri, K.Tanaka, N.Tamura, K.TOi, T.Tokuzawa, S.TOda, K.Tsumori, I.Yamada, O.Yamagishi, M.Yokoyama, S.Yoshimura, Y.Yoshimura, M.Yoshinuma, K.Ida, T.Shimozuma, K.Y.Watanabe, Y.Nagayama, O.Kaneko, T.Mutoh, K.Kawahata, H.Yamada, A.Komori, S.Sudo, O.Motojima

    21st IAEA Fusion Energy Conference, Chengdu, China, Oct.16-21, 2006     頁: EX/8-1   2006年

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    記述言語:英語  

  401. Bursty Fluctuation Characterisitics in SOL/Divertor Plasmas of Large Helical Device

    N.Ohno, S.Masuzzaki, V.P.Budaev, H.Miyoshi, S.Takamura, T.Morisaki, N.Ohyabu, A.Komori

    21st IAEA Fusion Energy Conference, Chengdu, China, Oct 16-21, 2006     頁: EX/P4-20   2006年

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    担当区分:筆頭著者   記述言語:英語  

  402. Extended Steady-State and High=beta Regimes of Net-Current Free Heliotron Plasmas in the Large Helical Device

    O.Motojima, H.Yamada, A.Komori, O.Kaneko, K.Kawahata, T.Mito, T.Mutoh, N.Ohyabu K.Ida, S.Imagawa, Y.Nagayama, T.Shimozuma, K.Y.Watanabe, S.Masuzakim J.Miyazawa, S.Morita, S.Ohdachi, N.Ohno, K.Saito, S.Sakakibara, Y.Takeiri, N.Tamura, K.Toi, M.Tokitani, M.Yokoyama, M.Yoshinuma, K.Ikeda, A.Isayama, K.Ishii, S.Kubo, S.Murakami, K.Nagasaki, T.Seki, K.Takahata, H.Takenaga, LHD Experimental Group

    21st IAEA Fusion Energy Conference, Chengdu, China, Oct.16-21. 2006     頁: OV/2-1   2006年

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    記述言語:英語  

  403. Plasma-surface interaction, scrape-off layer and divertor physics: Implications for ITER

    B.Lipschultz, X.Bonnin, A.Kukushkin, A.Leonard, J.Roth, E.Tsitrone, D.Whyte, N.Asakura, D.Coster, G.Counsell, R.Doerner, R.Dux, G.Federici, M.Fenstermacher, W.Fundamenski, P.Ghendrih, A.Hermann, J.Hu, A.Kallenbach, S.Kasheninnikov, K.Krieger, G.Krienev, A.Kreter, B.Kurnaev, B.LaBombard, S.Lisgom A.Loarte, T.Nakano, R.Neu, N.Ohno, H.Pacher, J.Paley, Y.Pan, G.Pautasso, V.Philipps, R.Pitts, V.Riccardo, V.Rohde, D.Rudakov, P.Stangeb, S.Takamura, T.Tanabe, Y.Yang, S.Zhu

    21st IAEA Fusion Energy Confernece, Chnegdu, China, Oct.16-21, 2006     頁: IT/1-4   2006年

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    記述言語:英語  

  404. Effects of transient heat load on tungsten surface having sub-micron helium holes and bubbles

    S.Kajita, N.Ohno, S.Takamura

    33rd EPS Conference on Plasma Phys. Rome, 19-23 June 2006 ECA   30I 巻   頁: 4.137   2006年

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    記述言語:英語  

  405. Plasma Response on Penetraton of External Rotating Helical Magnetic Field in HYBTOK-II Tokamak Edge Plasma

    V.P.Budaev, I.M.Pankratov, S.Takamura, N.Ohno, S.Kajita, M.Takagi, H.Matsuno, M.Okamoto, S.Hosoi, Y.Hasebe, T.Yamada, A.Ya.Omelchenko, V.V.Olshansky

    33rd EPS Conference on Plasma Phys. Rome, 19-23 June 2006 ECA   30I 巻   頁: 4.109   2006年

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    記述言語:英語  

  406. Intermittency in laboratory and space plasma: comparative study of multifractal statistics

    V.P.Budaev, S.P.Savin, L.M.Zelenyi, S.Takamura, N.Ohno, N.Shevyrev

    33rd EPS Conference of Plasma Phys. Rome, 19-23 June 2006 ECA   30I 巻   頁: 1.064   2006年

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    記述言語:英語  

  407. Investigation and Application of the Line Intensity Ratio Method for the Measurement of Electron Density and Temperature

    S.Kajita, T.Hiraishi, N.Ohno, M.Okamoto, T.Nakano, S.Takamura

    13th International Congress on Plasma Physics, Kiev, May 22-26, 2006     頁: A151p   2006年

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    記述言語:英語  

  408. Dynamic Interaction between Disruptive Plasma and Wakk in the Small Tokamak HYBTOK-II

    M.Okamoto, T.Yamada, T.Hiraishi, Y.Kikuchi, N.Ohno, S.Takamura

    17th PSI Conference, Heifei, China, May 22-26, 2006     頁: 2-15   2006年

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    記述言語:英語  

  409. High Density Plasma Generation by RF Ohmic Discharge in Toroidal Divertor Simulator NAGDIS-T

    M.Nagase, H.Matsuda, N.Ohno, S.Takamura, M.Takagi

    17th PSI Conference, Heifei, China, May 22-26, 2006     頁: 3-16   2006年

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    記述言語:英語  

  410. Control of Energetic Electron Component in a Magnetically Confined Diffusion Ar Plasma 査読有り

    M.Pustylnik, N.Ohno, S.Takamura

    Japanese Journal of Applied Physics   45 巻 ( 2A ) 頁: 926-932   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  411. Validity of Electron Temperature Measurement by Using Boltzmann Plot Method in Radio Freauency Inductive Discharge in the Atmospheric Pressure Range 査読有り

    N.Ohno, M.Razzak, H.Ukai, S.Takamura, Y.Uesugi

    Plasma Fusion Res.   1 巻   頁: 028(9pages)   2006年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  412. The Effect of the Rotating Helical Fields on the Plasma Edge in the HYBTOK-II Tokamak 査読有り

    V.P.Budaev, I.M.Pankratov, S.Takamura, N.Ohno, M.Takagi, H.Matsuno, M.Okamoto, S.K.Saha

    Nucl. Fusion   46 巻   頁: S175-S180   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  413. Fast Ignition and Mode Transition of Radio Frequency Induction Plasmas at Atmospheric Pressure using tungsten Pin Electrode Array 査読有り

    M.Razzak, S.Takamura, N.Ohno

    Plasma Fusion Res.   1 巻   頁: 006/Letters(3pages)   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  414. Assessment of Meander-Line Antenna covered with Dielectric Material for LHW Heating 査読有り

    H.Matsuno, S.Takamura, S.Hosoi, N.Ohno

    Plasma & Fusion Res.   1 巻   頁: 0009(6pages)   2006年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  415. Fast Initiation and Mode Transition of Radio Frequency Induction Plasmas at Atmospheric Pressure Using Tungsten Pin Electrodes Array 査読有り 国際誌

    RAZZAK M. Abdur, TAKAMURA Shuichi, OHNO Noriyasu

    Plasma and Fusion Research   ( 1 ) 頁: 6 - 6   2006年

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    The effects of using an array of tungsten pin electrodes on the ignition dynamics of radio frequency (rf) discharges generated by inductively coupled plasma (ICP) technique at atmospheric pressure are investigated experimentally. The experimental observations reveal that the array of tungsten pin electrodes successfully enhance the initial discharges maintained by the strong electrostatic field with stable and fast ignition, which enables us to sustain efficient rf induction plasmas at atmospheric pressure range.

    DOI: 10.1585/pfr.1.006

  416. Validity of Electron Temperature Measurement by Using Boltzmann Plot Method in Radio Frequency Inductive Discharge in the Atmospheric Pressure Range 査読有り 国際誌

    OHNO Noriyasu, RAZZAK M. Abdur, UKAI Hiroshi, TAKAMURA Shuichi, UESUGI Yoshihiko

    Plasma and Fusion Research   ( 1 ) 頁: 28 - 28   2006年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    The validity of electron temperature measurement using the Boltzmann plot method was investigated in a radio frequency (rf) inductive discharge in the atmospheric pressure range. Since the Boltzmann plot method requires local thermal equilibrium (LTE), the parameter regions of electron temperature and electron density, in which the Boltzmann plot method is applicable, were analyzed in terms of a comparison of the spontaneous emission and collisional excitation to the excited states. It is observed that in our rf-inductive plasma near the atmospheric pressure range the Boltzmann plot method does not provide an exact measurement of electron temperature because of relatively low electron density, which does not satisfy the calculation criteria. An alternative method employing a combination of the Stark broadening measurement and the Saha-Boltzmann equation was demonstrated to more accurately determine the plasma parameters (electron temperature and electron density).

    DOI: 10.1585/pfr.1.028

  417. Design of a novel T-lclimmittance conversion circuit for dynamic and non-linear loads 査読有り 国際共著 国際誌

    Razzak M.A., Takamura S., Ohno N., Uesugi Y.

    Proceedings of 4th International Conference on Electrical and Computer Engineering, ICECE 2006     頁: 13 - 16   2006年

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:Proceedings of 4th International Conference on Electrical and Computer Engineering, ICECE 2006  

    In recent years, the immittance conversion topology [1] has become attractive as a novel power conversion strategy because of its features that a constant voltage source is converted to a constant current source and vice versa. However, the design of an ideal immittance circuit in the high-power (∼kW) and high-frequency (∼MHz) range is practically very important, especially when apply to a dynamic and non-linear load such as induction plasma. In this article, the design and development of an ideal T-LCL immittance circuit is reported. The performance of the designed immittance circuit is analysed by using a time-varying inductive plasma load.

    DOI: 10.1109/ICECE.2006.355278

    Scopus

  418. Optimum generation of high heat flux toroidal plasmas by RF ohmic discharge 査読有り 国際誌

    Masuda H., Kitahara H., Nagase M., Ohno N., Takamura S., Takagi M.

    32nd EPS Conference on Plasma Physics 2005, EPS 2005, Held with the 8th International Workshop on Fast Ignition of Fusion Targets - Europhysics Conference Abstracts   3 巻   頁: 1946 - 1949   2005年12月

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:32nd EPS Conference on Plasma Physics 2005, EPS 2005, Held with the 8th International Workshop on Fast Ignition of Fusion Targets - Europhysics Conference Abstracts  

    We have developed a new toroidal divertor plasma simulator, NAGDIS-T (NAGoya DIvertor plasma Simulator with Toroidal magnetic configuration). Plasma is generated by RF Joule discharge. In order to obtain high density plasmas relevant to divertor plasmas in fusion devices, we investigate the optimum condition of RF Joule discharge by varying gas pressure and driving frequency. The experimental result shows that the optimum condition strongly depends on these parameters. Copyright © (2005) by the European Physical Society (EPS).

    Scopus

  419. High-Z Dust Generation on Tungsten Surfaces due to Synergetic Erosion of Deuterium/Helium Plasma Exposures 査読有り

    西島 大, 天野 浩嗣, 大野 哲靖, 吉田 直亮, 高村 秀一

    プラズマ・核融合学会誌 = Journal of plasma and fusion research   81 巻 ( 9 ) 頁: 703 - 707   2005年9月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    Low-energy and high-flux plasma exposures on tungsten surfaces result in blister/hole formation. Subsequent He plasma exposure at 2,000 K on the blister-rich surface forms a hole structure on the surface, including the blister surface, and some blisters collapse due to recrystallization and bubble formation on the blister skin. Grain ejections were observed after deuterium plasma exposure at 550 K on a W surface on which a hole structure had formed due to He pre-exposure at 1,600 K.

    DOI: 10.1585/jspf.81.703

  420. Efficient Radio Frequency Inductive Discharges in Near Atmospheric Pressure Using Immittance Conversion Topology 査読有り

    Razzak M. Abdur, 高村 秀一, 上杉 喜彦, 大野 哲靖

    プラズマ・核融合学会誌 = Journal of plasma and fusion research   81 巻 ( 3 ) 頁: 204 - 211   2005年3月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:社団法人 プラズマ・核融合学会  

    A radio frequency (rf) inductive discharge in atmospheric pressure range requires high voltage in the initial startup phase and high power during the steady state sustainment phase. It is, therefore, necessary to inject high rf power into the plasma ensuring the maximum use of the power source, especially where the rf power is limited. In order to inject the maximum possible rf power into the plasma with a moderate rf power source of few kilowatts range, we employ the immittance conversion topology by converting a constant voltage source into a constant current source to generate efficient rf discharge by inductively coupled plasma (ICP) technique at a gas pressure with up to one atmosphere in argon. A novel T-LCL immittance circuit is designed for constant-current high-power operation, which is practically very important in the high-frequency range, to provide high effective rf power to the plasma. The immittance conversion system combines the static induction transistor (SIT)-based radio frequency (rf) high-power inverter circuit and the immittance conversion elements including the rf induction coil. The basic properties of the immittance circuit are studied by numerical analysis and verified the results by experimental measurements with the inductive plasma as a load at a relatively high rf power of about 4 kW. The performances of the immittance circuit are also evaluated and compared with that of the conventional series resonance circuit in high-pressure induction plasma generation. The experimental results reveal that the immittance conversion circuit confirms injecting higher effective rf power into the plasma as much as three times than that of the series resonance circuit under the same operating conditions and same dc supply voltage to the inverter, thereby enhancing the plasma heating efficiency to generate efficient rf inductive discharges.

    DOI: 10.1585/jspf.81.204

  421. Characteristic changes of deuterium retention on tungsten surfaces due to low-energy helium plasma pre-exposure 査読有り

    Nishijima D, Sugimoto T, Iwakiri H, Ye MY, Ohno N, Yoshida N, Takamura S

    JOURNAL OF NUCLEAR MATERIALS   337 巻 ( 1-3 ) 頁: 927 - 931   2005年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jnucmat.2004.10.011

    Web of Science

  422. Hydrogen Blister Formation on Cold-Worked Tungsten with Layered Structure 査読有り

    D.Nishijima, T.Sugimoto, M.Ye, N.Ohno, S.Takamura

    Jpn. J. Appl. Phys.   44 巻 ( 1A ) 頁: 380-382   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  423. Characterstic changes of deuterium rentention on tungsten surfaces due to low-energy helium plasma pre-exposure 査読有り

    D.Nishijima, T.Sugimoto, H.Iwakiri, M.Y.Ye, N.Ohno, N.Yoshida, S.Takamura

    Journal of Nuclear Materials   337-339 巻   頁: 927-931   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  424. Carbon dust formation from re-deposited layers in high-density hydrogen/helium plasmas in the NAGDIS-II device 査読有り

    N.Ohno, Y.Kobayashi, T.Sugimoto, S.Takamura

    Journal of Nuclear Materials   337-339 巻   頁: 35-39   2005年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  425. Neutral helium line emission for edge plasma conditions 査読有り

    F.B.Rosmej, R.Stamm, S.Fritzsche, H.Capes, M.Koubiti, Y.Marandet, V.S.Lisitsa, N.Ohno, S.Takamura, D.Nishijima

    Journal of Nuclear Materials   337-339 巻   頁: 1101-1105   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  426. Formation mechanism of bubbles and holes on tungsten surface with low-energy and high-flux helium plasma irradiation in NAGDIS-II 査読有り

    Dai. Nishijima, M.Y.Ye, N.Ohno, S.Takamura

    J. Nucl. Mater.   329-333 巻   頁: 1029-1033   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  427. Efficient Radio Frequency Inductive Discharge in Hear Atmospheric Pressure Using Imittance Conversion Topology 査読有り

    M.A.Razzak, S.Takamura, Y.Uesugi, N.Ohno

    J. Plasma Fusion Res.   81 巻 ( 3 ) 頁: 204-211   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  428. Overview of JT-60U progress towards steady-state advanced tokamak 査読有り

    S.Ide, N.Ohno, JT-60U Team

    Nuclear Fusion   45 巻   頁: S48-S62   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  429. Micron-Bubble Formation on Polycrystal Tungsten due to Low-Energy and high-Flux Helium Plasma Exposure 査読有り

    D.Nishijima, M.Miyamoto, H.Iwakiri, M.Ye, N.Ohno, K.Tokunaga, N.Yoshida, S.Takamura

    Nuclear Fusion   46 巻   頁: 561-564   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  430. Further Roughing of Tungsten Surface due to Transient Heat Load by Laser Irradiation during Helium Plasma Exposure 査読有り

    S.Kajita, D.Nishijima, N.Ohno, S.Takamura

    J. Plasma Fusion Res.   81 巻   頁: 745-746   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  431. High-Z Dust Generation on Tungsten Surface due to Synergetic Erosion of Deuterium/Helium Plasma Exposure 査読有り

    D.Nishijima, K.Amano, N.Ohno, N.Yoshida, S.Takamura

    J. Plasma Fusion Res.   81 巻   頁: 703-707   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  432. Suppression of Blister Formation and Deuterium Retention on Tungsten Surface due to Mechanical Polishing and Helium Pre-exposure 査読有り

    D.Nishijima, H.Iwakiri, K.Amano, M.Y.Ye, N.Ohno, K.Tokunaga, N.Yoshida, S.Takamura

    Nucl. Fusion   45 巻   頁: 669-674   2005年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  433. Transition from electrostatic-to-electromagnetic mode in a radio-frequency Ar inductively coupled plasma in atmospheric pressure 査読有り 国際誌

    Razzak MA, Kondo K, Uesugi Y, Ohno N, Takamura S

    JOURNAL OF APPLIED PHYSICS   95 巻 ( 2 ) 頁: 427 - 433   2004年1月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1063/1.1635650

    Web of Science

  434. Proposal of Modeified Child-Langmuir Formula Describing Space-Charge Limited Current in Plasma 査読有り

    Y.Hagino, N.Ohno, S.Takamura

    Contrib. Plasma Phys.   44 巻 ( 1-3 ) 頁: 144-149   2004年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  435. Visualization of Intermittent Blobby Plasma Transport in Attached and Detached Plasmas of the NAGDIS-II 査読有り

    N.Ohno, K.Furuta, S.Takamura

    J. Plasma Fusion Res.   80 巻 ( 4 ) 頁: 275-276   2004年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  436. Moving-Surface Plasma-Facing Components for Particle Control in Steady State Magnetic Fusion Devices 査読有り

    Y.Hirooka, H.Fukushima, N.Ohno, S.Takamura

    Fusion Science and Technology   45 巻   頁: 60-64   2004年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  437. Reconstruction of Velocity Distribution of density Bursts by Wavelet Analysis in the Linear Divertor Simulator NAGDIS-II 査読有り

    N.Ohno, V.P.Budaev, K.Furuta, H.Miyoshi, S.Takamura

    Contrib. Plasma Phys.   44 巻 ( 1-3 ) 頁: 222-227   2004年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  438. Space-Charge Limited Current from Plasma-Facing Material Surface 査読有り

    S.Takamura, N.Ohno, M.Y.Ye, T.Kuwabara

    Contrib. Plasma Phys.   44 巻 ( 1-3 ) 頁: 126-137   2004年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  439. Proposal of modified Child-Langmuir formula describing space-charge limited current in plasma 査読有り 国際誌

    Hagino Y, Ohno N, Takamura S

    CONTRIBUTIONS TO PLASMA PHYSICS   44 巻 ( 1-3 ) 頁: 144 - 149   2004年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1002/ctpp.200410019

    Web of Science

  440. Proof-of-principle experiments on the concept of moving-surface plasma-facing components - Hydrogen recycling over a titanium-gettered rotating drum 査読有り 国際誌

    Hirooka Y., Fukushima H., Ohno N., Takamura S.

    Fusion Engineering and Design   65 巻 ( 3 SPEC. ) 頁: 413 - 421   2003年4月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Fusion Engineering and Design  

    In the magnetic fusion community much attention has recently been directed to particle control in the existing confinement experiments, as it is recognized that the core plasma performance can directly be affected by the edge conditions. However, it is still true that there is no clear strategy to cope with the needs for steady-state reactor operation. That is that, due to the saturation nature, wall conditioning such as boronization is not applicable for fuel and impurity particles control in steady-state devices, requiring a start from enabling concepts development. As a possible solution, the concept of moving-surface plasma-facing components (MS-PFCs) was proposed in our previous work and in the present work proof-of-principle experiments have been conducted. In this concept, the plasma-facing surface is mechanically circulated out-of-pile for regeneration of particle capturing capabilities by coating getter films on it. A prototypical MS-PFC test unit has been constructed for these proof-of-principle experiments, employing a rotating copper drum as the moving surface and titanium as the getter material. It has been indicated that, from Hα light intensity data taken in front of the rotating target, relative to no getter cases, approximately 6% reduced hydrogen recycling has been achieved at steady state. In support of these data, a first-order particle balance model predicts a 7% reduction in hydrogen recycling. © 2003 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0920-3796(03)00011-5

    Scopus

  441. Ion temperature measurement using an ion sensitive probe in the LHD divertor plasma 査読有り 国際誌

    Ezumi N., Masuzaki S., Ohno N., Uesugi Y., Takamura S.

    Journal of Nuclear Materials   313-316 巻 ( SUPPL. ) 頁: 696 - 700   2003年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Nuclear Materials  

    The first reliable measurement of ion temperature in the divertor plasma of the Large Helical Device has been done by using an ion sensitive probe. The satisfactory current-voltage characteristics of the ion collector for evaluating the ion temperature were obtained at the outer part of the divertor leg. Furthermore, simultaneous ion and electron temperature measurements were successfully done in this part. The results show that the ion temperature is higher than the electron temperature in the part. There is a possibility that the profiles of the evaluated ion temperature which shows relatively higher than the electron temperature at the outside of divertor leg are qualitatively explained by particle's orbits around the edge and divertor region. © 2003 Elsevier Science B.V. All rights reserved.

    DOI: 10.1016/S0022-3115(02)01364-8

    Scopus

  442. Experimental evaluation of space charge limited emission current from tungsten surface in high density helium plasma 査読有り 国際誌

    Hagino Y., Ohno N., Takamura S., Ye M.

    Journal of Nuclear Materials   313-316 巻 ( SUPPL. ) 頁: 675 - 678   2003年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Nuclear Materials  

    The experimental evaluation of space charge limited emission current from tungsten surface in high density helium plasma was done. It was found that the space charge limited current from the tungsten target plate saturated with an increase in sheath voltage. The space charge effect was predicted on the basis of boundary conditions of zero electric field on the material surface.

    DOI: 10.1016/S0022-3115(02)01381-8

    Scopus

  443. 非接触再結合プラズマ中の揺動特性 査読有り

    大野哲靖、田中直行、高村秀一

      7 巻 ( 10 ) 頁: 1093-1101   2003年

     詳細を見る

    担当区分:筆頭著者   記述言語:日本語   掲載種別:研究論文(学術雑誌)  

  444. Transition from Electrostatic to Electromagnetic Mode in a Radio Frequency Ar Induction Plasma in Atmospheric Pressure 査読有り

    M.A.Razzak, K.Kondo, Y.Uesugi, N.Ohno, S.Takamura

    J. Appl. Phys.   95 巻 ( 2 ) 頁: 427-433   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  445. Intermittent structures in the high field side boundary of the HYBTOK-II tokamak 査読有り

    V.P.Budaev, S.Takamura, Y.Kikuchi, Y.Uesugi, N.Ohno

    Czechoslovak Journal of Phys   53 巻 ( 10 ) 頁: 863-868   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  446. Formation and dynamics of very deep negative potential well in the small tokamak device CSTN-IV 査読有り

    H.Kojima, Y.Fukuzawa, T.Manabe, S.Takamura, T.Okada, N.Ohno

    Czechoslovak Journal of Phys.   53 巻 ( 10 ) 頁: 895-902   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  447. プラズマと接する固体表面からの空間電荷制限放出電流 査読有り

    高村秀一、大野哲靖

    放電研究   46 巻 ( 3 ) 頁: 2-22   2003年

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)  

  448. Proof of principle experiments on the concept of moving-surface plasma-facing components-hydrogen recycling over a titanium-gettered ratating drum 査読有り

    Y.Hirooka, H.Fukushima, N.Ohno, S.Takamura

    Fusion Engineering and Design   6 巻   頁: 413-421   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  449. Blister formation on tungsten surface under low energy and high flux hydrogen plasma irradiation in NAGDIS-I 査読有り

    M.Y.Ye, H.Kanehara, S.Fukuta, N.Ohno, S.Takamura

    Journal of Nuclear Materials   313-316 巻   頁: 72-76   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  450. Incident ion energy dependence of bubble formation on tungsten surface with low energy and high flux helium plasma irradiation 査読有り

    D.Nishijima, M.Y.Ye, N.Ohno, S.Takamura

    Journal of Nuclear Materials   313-316 巻   頁: 97-101   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  451. Experimental evaluation of space charge limited emission current from tungstn surface in high density helium plasma 査読有り

    Y.Hagino, N.Ohno, S.Takamura, M.Y.Ye

    Journal of Nuclear Materials   313-316 巻   頁: 675-678   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  452. Ion temperature measurement using an ion sensitie probe in the LHD divertor 査読有り

    N.Ezumi, S.Masuzaki, N.Ohno, Y.Uesugi, S.Takamura, LHD Experimental Group

    Journal of Nuclear Materials   313-316 巻   頁: 696-700   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  453. High-quality video streaming system for plasma diagnostics using super SINET 査読有り

    M.Emoto, K.Watanabe, S.Masuzaki, N.Ohno, H.Okade

    Rev. Sci. Instrum.   74 巻   頁: 1766   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  454. Self-consistent dusty sheaths in plasmas with two-temperature electrons 査読有り

    Yu.I.Chutov, O.Kravchenko, A.Pshenychnyj, R.Smirnov, K.Asano, N.Ohno, S.Takamura, Y.Tomita

    Physics of Plasmas   10 巻 ( 2 ) 頁: 546-552   2003年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  455. Fluctuation Characteristics in Detached Recombining Plasmas

    N.Ohno, N.Tanaka, S. Takamura, V.Budaev

    AIP Conference Proceedings   669 巻   頁: 240-243   2003年

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    担当区分:筆頭著者   記述言語:英語  

  456. Edge Plasma Turbulence in Fusion Devices: Bursty Behavior and Fractal Properties

    V.P.Budaev, S.Takamura, N.Ohno, A.Komori, S.Masuzaki, G.S.Kirnev, S.A.Grashin

    30th EPS Conference on Contr. Fusion and Plasma Phys., St. Petersburg, 7-11 July 2003 ECA   27A 巻   頁: 3.174   2003年

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    記述言語:英語  

  457. Intermittent Structures in the High Field Side Boundary of the HYBTOK-II Tokamak

    V.P.Budaev, S.Takamura, Y.Kikuchi, Y.Uesugi, N.Ohno

    30th EPS Conference on Contr. Fusion and Plasma Phys., St. Petersburg, 7-11 July 2003 ECA   27A 巻   頁: 3.173   2003年

     詳細を見る

    記述言語:英語  

  458. Surface Morphology of Tungsten Irradiated by Low-Energy and High-Flux Steady State Helium Plasma

    D.Nishijima, M.Y.Ye, N.Ohno, S.Takamura

    30th EPS Conference on Contr. Fusion and Plasma Phys., St.Petersburg, 7-11 July 2003 ECA   27-A 巻   頁: 2.163   2003年

     詳細を見る

    記述言語:英語  

  459. Structural Dynamics of Deep Negative Potential Well Formation in Small Tokamak Device CSTN-IV

    H.Kojima, Y.Fukuzawa, T.Manabe, N.Ohno, S.Takamura

    30th EPS Conference on Contr. Fusion and Plasma Phys., St.Petersburg, 7-11 July 2003 ECA   27A 巻   頁: 2.130   2003年

     詳細を見る

    記述言語:英語  

  460. Experimental Observation and Statistical Analysis of Density Bursts in the Linear Divertor Simulator NAGDIS-II

    N.Ohno, K.Furuta, H.Miyoshi, S.Takamura, V.P.Budaev

    30th EPS Conference on Contr. Fusion and Plasma Phys., St. Petersburg, 7-11 July 2003 ECA   27A 巻   頁: 2.154   2003年

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    担当区分:筆頭著者   記述言語:英語  

  461. Influence of the Ion Beam on the Behavior of Dust Particles Trapped in an Ion Sheath

    T.Murakami, M.Sawai, T.Misawa, N.Ohno, S.Takamura

    AIP Conference Proceedings   669 巻   頁: 101-104   2003年

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    記述言語:英語  

  462. Sound Wave Propagation in Gases at Low Pressure

    T.Tonogaki, N.Ohno, S.Takamura, A.Tsushima

    AIP Conference Proceedings   669 巻   頁: 113-116   2003年

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    記述言語:英語  

  463. 25aA28P LHD周辺プラズマにおける密度揺動の統計的解析(ヘリカル) 査読有り

    三好 秀暁, 高村 秀一, 大野 哲靖, 増崎 貴, 小森 彰夫, Budaev V.P.

    プラズマ・核融合学会年会予稿集   ( 20 )   2003年

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    出版者・発行元:プラズマ・核融合学会  

  464. 28aA17P プラズマ-シース境界に捕捉された微粒子の不安定振動に対する高温電子成分の影響(慣性核融合、プラズマ基礎・応用) 査読有り

    小林 篤弘, 今里 香恵, 大野 哲晴, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 20 )   2003年

     詳細を見る

    出版者・発行元:プラズマ・核融合学会  

  465. 27pB22P 接触・非接触プラズマ中の揺動特性(ミラー・CT等) 査読有り

    古田 賢寛, 大野 哲靖, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 20 )   2003年

     詳細を見る

    出版者・発行元:プラズマ・核融合学会  

  466. 26aA40P トカマク装置を用いた電極バイアスによる電位井戸の形成(トカマク) 査読有り

    福澤 祐馬, 小島 寛樹, 岡田 享大, 大野 哲靖, 高村 秀一, 井口 哲夫

    プラズマ・核融合学会年会予稿集   ( 20 )   2003年

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    出版者・発行元:プラズマ・核融合学会  

  467. 25aB37P 高熱流トロイダル・ダイバータプラズマ模擬試験装置の製作と性能試験(真空・第一壁・材料,炉設計) 査読有り

    空 重希, 北原 弘義, 大野 哲靖, 上杉 喜彦, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 20 )   2003年

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    出版者・発行元:プラズマ・核融合学会  

  468. 25aB11P 低エネルギー高粒子束水素プラズマ照射による低温高融点金属表面におけるブリスタ形成実験(真空・第一壁・材料,炉設計) 査読有り

    杉本 喬紀, 大野 哲靖, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 20 )   2003年

     詳細を見る

    出版者・発行元:プラズマ・核融合学会  

  469. Generation and characteristics of a detached recombining plasma and its dynamic behaviour-a bridge between fusion plasmas and low-temperature ionized gases 査読有り 国際誌

    Takamura S, Ohno N, Nishijima D, Uesugi Y

    PLASMA SOURCES SCIENCE & TECHNOLOGY   11 巻 ( 3A ) 頁: A42 - A48   2002年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Web of Science

  470. Characteristics of detached plasmas associated with electron-ion and molecular assisted recombinations in NAGDIS-II 査読有り 国際共著 国際誌

    Nishijima D., Wenzel U., Ohsumi K., Ohno N., Uesugi Y., Takamura S.

    Plasma Physics and Controlled Fusion   44 巻 ( 5 ) 頁: 597 - 610   2002年5月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Plasma Physics and Controlled Fusion  

    Recombination in a helium and helium-hydrogen plasma was experimentally investigated in the linear divertor simulator NAGDIS-II. To identify the physical mechanisms, electron-ion recombination (EIR) and molecular assisted recombination (MAR), the plasma parameters in the recombining region have been measured. We used spectroscopic techniques on the basis of continuum emission and line emission from highly excited levels due to EIR and Langmuir probes. The dependence of the plasma parameters on the neutral pressure in a pure helium plasma and in a helium-hydrogen mixture shows clearly that recombination is caused by different processes in the two cases. In a pure helium plasma a roll-over and a following decrease of the electron density as well as a monotonic decrease of the electron temperature down to 0.1 eV were observed when increasing the helium pressure. Here EIR is the recombination mechanism. Conversely, when hydrogen is added to the helium plasma, the electron density decreases monotonically while the central electron temperature remains above 1 eV. This particular behaviour in the helium-hydrogen plasma can only be explained by the dominant action of MAR.

    DOI: 10.1088/0741-3335/44/5/307

    Scopus

  471. Response to "comment on 'dynamic behaviors of dust particles in the plasma-sheath boundary'" [Phys. Plasmas 9, 1057 (2002)] 査読有り 国際誌

    Takamura S., Ohno N., Misawa T., Nunomura S.

    Physics of Plasmas   9 巻 ( 3 )   2002年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physics of Plasmas  

    DOI: 10.1063/1.1446462

    Scopus

  472. Proposal of Flexible Atomic and Molecular Process Management for Monte Carlo Impurity Transport Code Based on Object Oriented Method 査読有り

    K.Asano, N.Ohno, S.Takamura

    Contrib. Plasma Physics   42 巻   頁: 157-162   2002年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  473. Generation and characteristics of detached recombining plasma and its dynamic behaviour - a bridge between fusion plasmas and low-temperature ionized gases 査読有り

    S.Takamura, N.Ohno, D.Nishijima, Y.Uesugi

    Plasma Sources Sci. Technol.   11 巻 ( 3A ) 頁: A42-A4   2002年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  474. Response to Comment on "Dynamic Behaviours of Dust Particles in the Plasma Sheath Boundary" 査読有り

    S.Takamura, N.Ohno, T.Misawa, S.Nunomura

    Physics of Plasmas   9 巻   頁: 1060-1061   2002年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  475. Characteristics of Detached Plasmas Associated with Electron-Ion and Molecular Assisted Recombination in NAGDIS-II 査読有り

    D.Nishijima, U.Wenzel, K.Ohsumi, N.Ohno, Y.Uesugi, S.Takamura

    Plasma Physics Controlled Fusion   44 巻   頁: 597-610   2002年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  476. Parametric Excitation of a Dust Particle Trapped in a Plasma-Sheath Boundary 査読有り

    N.Ohno, M.Sawai, T.Misawa, K.Asano, S.Takamura

    Physica Scripta   T98 巻   頁: 81-86   2002年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  477. Analysics of Detached Recombining Plasmas by Collisional-Radiative Model with Energetic Electron Component 査読有り

    N.Ohno, M.Motoyama, S.Takamura

    Contrib. Plasma Physics   42 巻   頁: 419-424   2002年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  478. Heat Pulse in a Simulated Divertor Plasmas

    Y.Uesugi, S.Takamura, K.Ohsumi, N.Ohno, D.Nishijima

    29th EPS Conference on Contr. Fusion and Plasma Phys., Montroux, Switzerland, 17-21 June 2002 ECA   26B 巻   頁: 1.087   2002年

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    記述言語:英語  

  479. 26aB13P 低エネルギー・高粒子束ヘリウムプラズマのタングステンへの照射(真空・第一壁・材料) 査読有り

    西島 大, 叶 民友, 大野 哲靖, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 19 )   2002年

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    出版者・発行元:プラズマ・核融合学会  

  480. Analysis of detached recombining plasmas by collisional-radiative model with energetic electron component 査読有り 国際誌

    Ohno N, Motoyama M, Takamura S

    CONTRIBUTIONS TO PLASMA PHYSICS   42 巻 ( 2-4 ) 頁: 419 - 424   2002年

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    担当区分:筆頭著者   記述言語:英語  

    Web of Science

  481. 28pB09 空間電荷制限領域におけるプラズマと接する固体表面からの熱電子放出の実験的評価(真空・第一壁・材料) 査読有り

    萩野 喜晴, 叶 民友, 大野 哲靖, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 19 )   2002年

     詳細を見る

    出版者・発行元:プラズマ・核融合学会  

  482. 26pA07 交流トカマク放電によるプラズマ熱流を用いた熱電子放出(プラズマ基礎・応用II) 査読有り

    真鍋 俊治, 小島 寛樹, 福澤 祐馬, 大野 哲靖, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 19 )   2002年

     詳細を見る

    出版者・発行元:プラズマ・核融合学会  

  483. 26aB18P 移動表面式プラズマ対向機器による粒子制御の原理検証実験(真空・第一壁・材料) 査読有り

    廣岡 慶彦, 福島 宝寿, 大野 哲靖, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 19 )   2002年

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    出版者・発行元:プラズマ・核融合学会  

  484. 直線型プラズマ装置を用いた高融点金属材料の損耗・再堆積モデル実験 査読有り

    大野 哲靖, 高村 秀一

    プラズマ・核融合学会誌 = Journal of plasma and fusion research   77 巻 ( 9 ) 頁: 864 - 868   2001年9月

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    担当区分:筆頭著者   記述言語:日本語   掲載種別:研究論文(学術雑誌)   出版者・発行元:プラズマ・核融合学会  

    Erosion and redeposition processes of molybdenum, a high-Z material, were investigated in the linear plasma device TPD-I. Comparison between the experimental results and numerical analysis with a 3D Monte Carlo simulation code indicated that the observed erosion profile could be explained by taking account of the effect of prompt redeposition of high-Z material.

  485. Static and dynamic behaviour of plasma detachment in the divertor simulator experiment NAGDIS-II 査読有り 国際共著 国際誌

    Ohno N., Nishijima D., Takamura S., Uesugi Y., Motoyama M., Hattori N., Arakawa H., Ezumi N., Krasheninnikov S., Pigarov A., Wenzel U.

    Nuclear Fusion   41 巻 ( 8 ) 頁: 1055 - 1065   2001年8月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Nuclear Fusion  

    A comprehensive investigation has been performed of the static and dynamic behaviour of detached recombining plasmas in the linear divertor plasma simulator NAGDIS-II. For stationary plasma detachment, the transition from electron ion recombination (EIR) to molecular activated recombination (MAR) has been observed by injecting hydrogen gas into high density helium plasmas. The particle loss rate due to MAR is found to be comparable to that of EIR. Experiments have also been performed by the injection of a plasma heat pulse produced by RF heating into the detached helium plasma to demonstrate the dynamic behaviour of volumetric plasma recombination. Negative spikes in the Balmer series line emission were observed and found to be similar to the so called negative ELM observed in tokamak divertors. Observed Balmer spectra were analysed in detail using the collisional-radiative model. A rapid increase of the ion flux to the target plate was observed associated with the re-ionization of the highly excited atoms generated by EIR.

    DOI: 10.1088/0029-5515/41/8/309

    Scopus

  486. Evidence for the importance of radial transport in plasma detachment in the Nagoya University Divertor Simulator (NAGDIS-II) 査読有り 国際誌

    Hollmann E., Whyte D., Nishijima D., Ohno N., Uesugi Y., Ezumi N.

    Physics of Plasmas   8 巻 ( 7 ) 頁: 3314 - 3320   2001年7月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physics of Plasmas  

    Measurements of ion and electron temperatures have been performed in detaching helium -hydrogen plasmas in a linear divertor simulator experiment using spectroscopy, a Langmuir probe, and an omegatron mass spectrometer. Detachment in these plasmas is characterized by a significant (≈20×) reduction in the central plasma flux at the target plate as the target region neutral pressure is increased from 2 to 12 mTorr. The data indicate that partially detached gas-target plasmas consist of a hot (Te≈5 eV) core region along the axis of the plasma column, surrounded by a cold (Te ≈0.1 eV) halo region of recombining plasma. At Te = 5 eV, plasma recombination is negligible compared with ionization; these experiments therefore provide evidence that detachment is primarily caused by radial transport and by a gradual drop in the ionization source as the temperature of the core region drops below 5 eV. © 2001 American Institute of Physics.

    DOI: 10.1063/1.1372664

    Scopus

  487. Dynamic behavior of detached recombining plasmas during ELM-like plasma heat pulses in the divertor plasma simulator NAGDIS-II 査読有り 国際誌

    Uesugi Y, Hattori N, Nishijima D, Ohno N, Takamura S

    JOURNAL OF NUCLEAR MATERIALS   290 巻   頁: 1134 - 1137   2001年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    Web of Science

  488. Evaluation of electron temperature in detached recombining plasmas 査読有り 国際共著 国際誌

    Nishijima D., Wenzel U., Motoyama M., Ohno N., Takamura S., Krasheninnikov S.

    Journal of Nuclear Materials   290-293 巻   頁: 688 - 691   2001年3月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Nuclear Materials  

    Detailed spectroscopic measurements have been carried out in the linear divertor plasma simulator, NAGDIS-II in order to acquire the accurate evaluation of the electron temperature, which leads to a deeper understanding of the characteristics of detached recombining plasmas. Electron temperature in the detached recombining plasmas was evaluated by two different spectroscopic methods, using continuum emission and a series of line emission from highly excited levels, giving different electron temperatures. The reasons are discussed based on the effects of energetic electrons.

    DOI: 10.1016/S0022-3115(00)00528-6

    Scopus

  489. Experimental observation of vertically polarized transverse dust-lattice wave propagating in a one-dimensional strongly coupled dust chain 査読有り 国際誌

    Misawa T., Ohno N., Asano K., Sawai M., Takamura S., Kaw P.K.

    Physical Review Letters   86 巻 ( 7 ) 頁: 1219 - 1222   2001年2月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Physical Review Letters  

    The existence of transverse dust-lattice wave (T-DLW) propagating in a one-dimensional strongly coupled dust chain levitated in dc argon plasma at low gas pressure was assessed. Both parts of the complex wave number were measured in the experiments. The real part showed that the T-DLW propagation as a backward wave.

    DOI: 10.1103/PhysRevLett.86.1219

    Scopus

  490. Experimental Observation of Vertically Polarized Transverse Dust Lattice Wve Propagating in a One Dimensional Strongly Coupled Dust Chain 査読有り

    T.Misawa, N.Ohno, K.Asano, M.Sawai, S.Takamura, P.K.Kaw

    Physcal Review Letters   86 巻 ( 7 ) 頁: 1219-1222   2001年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  491. Influence of Plasma Resistance and Fluctuation on Probe Characeteristics in Detached Recombining Plasmas 査読有り

    N.Ohno, N.Tanaka, N.Ezumi, D.Nishijima, S.Takamura

    Contib. Plasma Physics   41 巻   頁: 473-480   2001年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  492. Static and Dynamic Behaviors of Detached Plasma in Divertor Simulator NAGDIS-II 査読有り

    S.Takamura, N.Ohno, Y.Uesugi, D.Nishijima, K.Ohsumi, M.Motoyama, N.Hattori, N.Ezumi, S.Krasheninnikov, A.Pigarov, U.Wenzel

    Journal of Plasma and Fusion Research SERIES   4 巻   頁: 138-145   2001年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  493. Dynamic Behaviors of Dust Particles in the Plasma-Sheath Boundary 査読有り

    S.Takamura, T.Misawa, N.Ohno, S.Nunomura, M.Sawai, K.Asano, P.K.Kaw

    Physics of Plasmas   8 巻 ( 5 ) 頁: 1886-1892   2001年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  494. プラズマと接する固体表面からの空間電荷制限電流 査読有り

    桑原竜弥、大野哲靖、高村秀一、叶民友

      77 巻 ( 5 ) 頁: 464-475   2001年

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    記述言語:日本語   掲載種別:研究論文(学術雑誌)  

  495. Evidence for the Importance of Radial Transport in Plasma Detacment in the Nagoya University Divertor Simulator(NAGDIS-II) 査読有り

    E.M.Hollmann, D.G.Whyte, D.Nishijima, N.Ohno, Y.Uesugi, N.Ezumi

    Physics of Plasmas   8 巻 ( 7 ) 頁: 3314-3320   2001年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  496. *Static and Dynamic Behavior of Plasma Detachment in the Divertor Simulator Experiment NAGDIS-II 査読有り

    N.Ohno, D.Nishijima, S.Takamura, Y.Uesugi, M.Motoyama, N.Hattori, H.Arakawa, N.Ezumi, S.Krasheninnikov, A.Pigarov, U.Wenzel

    Nuclear Fusion   41 巻 ( 8 ) 頁: 1055-1065   2001年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

  497. Evaluation of Electron Teperature in Detached Recombining Plasma 査読有り

    D.Nishijima, U.Wenzel, M.Motoyama, N.Ohno, S.I.Krasheninnikov, S.Takamura

    Journal of Nuclear Materials   290-293 巻   頁: 688-691   2001年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  498. 小特集「プラズマ対向面での損耗・再堆積研究の進展」3.直線型プラズマ装置を用いた高融点金属材料の損耗・再堆積モデル実験

    大野哲靖、高村秀一

    プラズマ・核融合学会誌   77 巻 ( 9 ) 頁: 864-868   2001年

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    担当区分:筆頭著者   記述言語:日本語  

  499. Dynamic Response of Detached Recombining Plasmas to ELM-Like Plasma Heat Pulse Produced by RF Heating

    K.Ohsumi, D.Nishijima, N.Ohno, Y.Uesugi, S.Takamura

    Proc. of XXV International Conference on Phenomena in Ionized Gases, Nagoya, Japan     頁: 195-196   2001年

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    記述言語:英語  

  500. Influence of Supra-Thermal Electrons on Propagation of Transverse Dust Lattice Wave

    T.Misawa, K.Asano, M.Sawai, N.Ohno, S.Takamura

    Proc. of XXV International Conference on Phenomena in Ionized Gases, Nagoya, Japan     頁: 65-66   2001年

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    記述言語:英語  

  501. MD Particle Simulation on Dust Lattice Wave

    K.Asano, T.Misawa, N.Ohno, S.Takamura, S.Vladimirov

    Proc. of XXV International Conference on Phenomena in Ionized Gases, Nagoya, Japan     頁: 61-62   2001年

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    記述言語:英語  

  502. Fluctuations in Detached Recombining Plasmas

    N.Tanaka, N.Ohno, S.Takamura

    Proc. of XXV International Conference on Phenomena in Ionized Gases, Nagoya, Japan     頁: 345-346   2001年

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    記述言語:英語  

  503. Modifications of Tungsten Surface under Low Ionic Energy and High Flux Plasma Irradiation

    K.Moriguchi, S.Fukuta, M.Y.Ye, N.Ohno, S.Takamura

    Proc. of XXV International Conference on Phenomena in Ionized Gases, Nagoya, Japan     頁: 83-84   2001年

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    記述言語:英語  

  504. 27aA01 [招待講演]非接触プラズマにおける再結合過程とその動的応答(プラズマ基礎・応用) 査読有り

    大野 哲靖, 高村 秀一, 上杉 喜彦, 西島 大輔, 大住 光一, 田中 直行, 嶋崎 弘志

    プラズマ・核融合学会年会予稿集   ( 18 )   2001年

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    出版者・発行元:プラズマ・核融合学会  

  505. 30pA17P イオンセンシティブプローブを用いたPSI-2プラズマのイオン温度計測(プラズマ計測) 査読有り

    江角 直道, 大野 哲靖, 高村 秀一, 勝俣 五男, 増崎 貴, Kiss'ovski Zh., Bohmeyer W., Fussmann G., PSI-2実験グループ PSI-2実験グループ

    プラズマ・核融合学会年会予稿集   ( 18 )   2001年

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    出版者・発行元:プラズマ・核融合学会  

  506. 29pA20P 移動表面式プラズマ対向機器による粒子制御の原理検証実験(加熱/炉設計) 査読有り

    福島 宝寿, 廣岡 慶彦, 大野 哲靖, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 18 )   2001年

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    出版者・発行元:プラズマ・核融合学会  

  507. 28aB15P ホイッスラー波により生成されたELM様熱パルスに対する非接触再結合プラズマの動的応答(加熱/炉設計) 査読有り

    大住 光一, 西島 大輔, 大野 哲靖, 上杉 喜彦, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 18 )   2001年

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    出版者・発行元:プラズマ・核融合学会  

  508. 27pA12P 非接触再結合プラズマ中の揺動計測(2)(プラズマ基礎・応用) 査読有り

    田中 直行, 大野 哲靖, 高木 誠, 高村 秀一, Budaev V.

    プラズマ・核融合学会年会予稿集   ( 18 )   2001年

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    出版者・発行元:プラズマ・核融合学会  

  509. 27pA11P 時間依存衝突幅射コードと流体コードによる非接触プラズマの動的挙動解析(プラズマ基礎・応用) 査読有り

    嶋崎 弘志, 大野 哲靖, 高村 秀一

    プラズマ・核融合学会年会予稿集   ( 18 )   2001年

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    出版者・発行元:プラズマ・核融合学会  

  510. Influence of plasma resistance and fluctuation on probe characteristics in detached recombining plasmas 査読有り 国際誌

    Ohno N., Tanaka N., Ezumi N., Nishijima D., Takamura S.

    Contributions to Plasma Physics   41 巻 ( 5 ) 頁: 473 - 480   2001年

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Contributions to Plasma Physics  

    In order to find the causes of the strong anomaly of current-voltage characteristics of Langmuir probe observed in detached recombining plasmas in a linear divertor plasma simulator, NAGDIS-II, we have investigated plasma resistance along a magnetic field and potential fluctuations in the detached recombining plasmas. Simple calculation on the ratio between the plasma length, at which plasma resistance and resistance of ion sheath formed around a probe tip become equal, and an electron collection length indicates that the evaluation of electron temperature Te becomes inaccurate at Te of less than 0.6 eV when plasma density and neutral pressure are 1.0 × 1018 m-3 and 10 mtorr, respectively. The potential fluctuation in detached recombining plasmas was found to be so large compared to Te/e, which can also modify the probe characteristics.

    DOI: 10.1002/1521-3986(200109)41:5<473::AID-CTPP473>3.0.CO;2-8

    Scopus

  511. Peter C. Stangeby著, The Plasma Boundary of Magnetic Fusion Devices (Institute of Physics Publishing, Bristol and Philadelphia, B5版, 717頁, 2000年, £125, $195, ハードカバー) 査読有り

    大野 哲靖

    プラズマ・核融合学会誌 = Journal of plasma and fusion research   76 巻 ( 10 )   2000年10月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:論文集(書籍)内論文   出版者・発行元:プラズマ・核融合学会  

  512. Fundamental Processes of Plasma Heat Flow through Sheaths to Material Surfaces in Recent Research Development in Plasmas Vol.1-2000

    S.Takamura, M.Y.Ye, N.Ohno, Y.Uesugi

    Transworld Research Network, 2000, pp.41-64     頁: 41-64   2000年

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    記述言語:英語  

  513. Detached Recombining Plasmas in relation to Volumetric Hydrogen Recycle in Hydrogen Recycling at Plasma Facing Materials, ed. by C.H.Wu

    S.Takamura, N.Ohno, N.Ezumi, D.Nishijima, S.I.Krasheninnikov, A.Yu. Pigarov

    NATO Science Series, II. Mathematics, Physics and Chemistry, Vol. 1, Kluwer Academic Publishers   1 巻   頁: 59-66   2000年

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    記述言語:英語  

  514. Fundamental Process of Plasma Heat Flow through Sheaths to Material Surfaces in Recent Research Development in Plasmas 査読有り

    S.Takamura, M.Y.Ye, N.Ohno, Y.Uesugi

    Transworld Research Network     頁: 41-64   2000年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  515. Dynamic Behavior of Detached Recombining Plasmas during ELM-like Plasma Heat Pulse in the Diverotr Plasma Simulator NAGDIS-II 査読有り

    Y.Uesugi, N.Hattori, D.Nishijima, N.Ohno, S.Takamura

    Journal of Nuclear Materials   290-293 巻   頁: 1134-1137   2000年

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    記述言語:英語   掲載種別:研究論文(学術雑誌)  

  516. Effects of Condensible Impurities on the Erosion Behavior of the Plasma-Facing Materials 査読有り

    N.Ohno, S.Uno, Y.Hirooka, S.Takamura

    Journal of Nuclear Materials   290-293 巻   頁: 299-302   2000年