Updated on 2024/02/09

写真a

 
NIWA, Ken
 
Organization
Graduate School of Engineering Associate professor
Graduate School
Graduate School of Engineering
Undergraduate School
School of Engineering Physical Science and Engineering
Title
Associate professor

Degree 1

  1. Doctor of Science

Research Areas 2

  1. Nanotechnology/Materials / Inorganic materials and properties

  2. Others / Others  / Inorganic Material/Physical Properties

Current Research Project and SDGs 1

  1. Material synthesis under ultrahigh-pressure

Research History 2

  1. Nagoya University   Associate professor

    2015.10

  2. Nagoya University   Assistant Professor

    2008.4 - 2015.9

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    Country:Japan

Education 1

  1. The University of Tokyo   Graduate School, Division of Science

    - 2008.3

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    Country: Japan

Professional Memberships 4

  1. The Japan Society of High Pressure Science and Technology

    2022.10

  2. The Japan Society of High Pressure Science and Technology

    2022.10

  3. 日本セラミックス協会

  4. The Japan Institute of Metals

 

Papers 76

  1. High-pressure synthesis and low-temperature thermal expansion behavior of homogeneous phosphorus-rich pseudo-binary compound (V0.5Cr0.5)P4 Reviewed

    Chang, CC; Sasaki, T; Gaida, NA; Niwa, K; Hasegawa, M

    CERAMICS INTERNATIONAL   Vol. 49 ( 24 ) page: 40990 - 40994   2023.12

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Ceramics International  

    A black phosphorus layered homogeneous phosphorus-rich compound – (V0.5Cr0.5)P4 is synthesized using a large volume press under conditions of P = 5 GPa, 1100 °C, and 1 h of heating. (V0.5Cr0.5)P4 has a monoclinic (C2/c) structure with lattice parameters and cell volume of a = 5.2307(3)Å, b = 10.861(4)Å, c = 5.8253(4)Å, β = 110.784°, and V = 309.41(4)Å3, respectively. The thermal expansion behavior above about 110K has been investigated by low-temperature synchrotron XRD. The coefficient of thermal expansion, α, was calculated to be αa = 0.57 × 10−5K−1, αb = 0.70 × 10−5K−1, αc = 0.92 × 10−5K−1, αβ = 0.13 × 10−5K−1 and αv = 2.10 × 10−5K−1 at 293K. This thermal expansion behavior presents an anisotropic expansion characteristic different from pure black phosphorus due to the V/Cr atom that bonded the black phosphorus layers together.

    DOI: 10.1016/j.ceramint.2023.09.176

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  2. Thermal expansion behavior of vanadium pernitride, CuAl2-type VN2, synthesized under high pressures Reviewed

    Asano, S; Niwa, K; Sasaki, T; Hasegawa, M

    PROGRESS IN SOLID STATE CHEMISTRY   Vol. 72   2023.12

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Progress in Solid State Chemistry  

    CuAl2-type VN2, which is synthesized under high pressure, is a recoverable material at ambient conditions and has a high bulk modulus. In this study, we investigated the thermal expansion behavior of CuAl2-type VN2 by low-temperature X-ray diffraction measurements between 109.3(5) K and 298.3(8) K. The axial thermal expansion coefficient of VN2 was determined to be αa = 2.7(9) × 10−6 K−1 and αc = 17.8(12) × 10−6 K−1 at 298.3(8) K, which has large anisotropy similar to that of compression behavior. It is found that the small coefficient of thermal expansion of the a-axis is due to the negative and positive effects on the a-axis length with increasing temperature of the bond angles and bond lengths of VN2, respectively. As a result, VN2 exhibits very large anisotropic thermal expansion behavior.

    DOI: 10.1016/j.progsolidstchem.2023.100426

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  3. High-Pressure Synthesis of a High-Pressure Phase of MnN Having NiAs-Type Structure Reviewed

    Asano, S; Niwa, K; Lawler, KV; Kawaguchi-Imada, S; Sasaki, T; Hasegawa, M

    INORGANIC CHEMISTRY   Vol. 62 ( 49 ) page: 20271 - 20278   2023.11

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Inorganic Chemistry  

    A novel high-pressure phase of manganese mononitride, NiAs-type MnN, was successfully synthesized through a pressure-induced phase transition from a tetragonal distorted NaCl-type MnN at pressures above approximately 55 GPa. High-pressure experiments, including starting material preparation, were conducted using a laser-heated diamond anvil cell. This result is the first example of a nitride with a structural phase transition from the distorted NaCl-type to the NiAs-type structure. Upon decompression after the phase transition to NiAs-type structure, the NiAs-type MnN underwent a structural change to the distorted NaCl-type phase, indicating the phase transition was reversible. NiAs-type MnN has a higher density and bulk modulus in comparison to the distorted NaCl-type one. The phase transition pressure of MnN is lower than that of oxides, such as FeO and MnO, which show a structural phase transition from a NaCl-type to a NiAs-type structure. It is suggested that this is due to the lattice distortion caused by antiferromagnetic ordering.

    DOI: 10.1021/acs.inorgchem.3c03241

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  4. 新規な14族元素窒化物の超高圧高温合成と結晶化学

    丹羽 健, 佐々木 拓也, 長谷川 正

    日本結晶学会誌   Vol. 65 ( Supplement ) page: s31 - s31   2023.10

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:日本結晶学会  

    DOI: 10.5940/jcrsj.65.s31

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  5. Synthesis of garnet-type Mn<sup>4+</sup>-activated Y<sub>3</sub>(Al,Ga)<sub>5</sub>O<sub>12</sub> and (Y,Gd)<sub>3</sub>Al<sub>5</sub>O<sub>12</sub> phosphors with controlled emission by cation substitution

    Sasaki Takuya, Asaka Ryota, Niwa Ken, Gaida Nico Alexander, Hasegawa Masashi

    Journal of the Ceramic Society of Japan   Vol. 131 ( 10 ) page: 696 - 700   2023.10

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:The Ceramic Society of Japan  

    <p>Ga- and Gd-substituted garnet-type Y<sub>3</sub>Al<sub>5</sub>O<sub>12</sub>:Mn<sup>4+</sup> phosphors, Y<sub>3</sub>(Al<sub>1−</sub><i><sub>x</sub></i>Ga<i><sub>x</sub></i>)<sub>5</sub>O<sub>12</sub>:Mn<sup>4+</sup> and (Y<sub>1−</sub><i><sub>y</sub></i>Gd<i><sub>y</sub></i>)<sub>3</sub>Al<sub>5</sub>O<sub>12</sub>:Mn<sup>4+</sup>, were synthesized by a conventional solid-state reaction to elucidate the relationship between the emission and the local structure of the activator in the host material. Completely substituted Y<sub>3</sub>(Al<sub>1−</sub><i><sub>x</sub></i>Ga<i><sub>x</sub></i>)<sub>5</sub>O<sub>12</sub> and ∼80 % substituted (Y<sub>1−</sub><i><sub>y</sub></i>Gd<i><sub>y</sub></i>)<sub>3</sub>Al<sub>5</sub>O<sub>12</sub> (<i>y</i> ≤ ∼0.8) solid solutions have been produced. The lattice parameters of the garnet-type solid solutions increased linearly with the substitution of Ga and Gd for Al and Y sites, respectively. The emission peak attributed to the Mn<sup>4+</sup> luminescence center of their garnet-type solid solutions shifted toward a longer wavelength side by substituting Ga and Gd. The emission peak wavelength of the Mn<sup>4+</sup>-activated garnet-type solid solutions increased almost linearly with increasing the average bond length between the cation and anion in the dodecahedral sites. The dodecahedral site in the garnet structure is edge-sharing with the octahedral site where Mn<sup>4+</sup> exists. These results indicate that the emission wavelength can be controlled by changing the local structure around Mn<sup>4+</sup> due to the cation substitution of coordination polyhedra neighboring Mn<sup>4+</sup> coordination polyhedra.</p>

    DOI: 10.2109/jcersj2.23063

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  6. Low-temperature thermal expansion behavior of the entropy-stabilized oxide (MgCoNiCuZn)O Reviewed

    Chang C.C., Sasaki T., Alexander Gaida N., Niwa K., Hasegawa M.

    Materials Letters   Vol. 347   2023.9

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Materials Letters  

    The coefficient of thermal expansion (CTE) of entropy-stabilized oxide (MgCoNiCuZn)O has been firstly experimentally measured and studied at low temperatures below room temperature. The temperature-dependent lattice parameters of (MgCoNiCuZn)O were determined by synchrotron X-ray diffractometry. A CTE value of α = 2.2780x10-5 K−1 at 113 K for (MgCoNiCuZn)O was calculated using a second-degree polynomial fitting. The quenched homogeneous NaCl-type (MgCoNiCuZn)O structure has the highest CTE value below 133 K among all its constituent oxides. An unquenched (MgCoNiCuZn)O was also investigated, and the homogeneity was found to affect CTE values. Finally, the anisotropic behavior of the constituent oxides and (MgCoNiCuZn)O were also compared.

    DOI: 10.1016/j.matlet.2023.134601

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  7. High Temperature and Pressure Synthesis, Compression Behaviors and Thermal Expansion of Novel Transition Metal Nitrides Reviewed

    Hasegawa Masashi, Asano Shuto, Chang Chung-Ching, Sasaki Takuyta, Niwa Ken

    Netsu Sokutei   Vol. 50 ( 1 ) page: 13 - 19   2023.1

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:The Japan Society of Calorimetry and Thermal Analysis  

    Pressure is one of the thermodynamic parameters together with the temperature to control the stability of materials. Ultra-high pressure in more than GPa regions allows us to obtain novel transition metal nitrides. This review shows a synthesis system under ultra-high pressures and high temperatures called laser-heating diamond anvil cell system in the first part. Then, our recent research results of the first synthesis of a novel niobium nitride, U<sub>2</sub>S<sub>3</sub>-type Nb<sub>2</sub>N<sub>3</sub> are described. In the second part, compression and thermal expansion behaviors of the U<sub>2</sub>S<sub>3</sub>-type Nb<sub>2</sub>N<sub>3</sub> are shown and compared with each other. Besides, the high pressure in-situ XRD and low temperature in-situ XRD measurement systems in the Aichi Synchrotron Radiation Center (Aichi SR) are also described briefly.

    DOI: 10.11311/jscta.50.1_13

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  8. High-pressure synthesis and crystal structures of molybdenum nitride Mo<sub>3</sub>N<sub>5</sub> with anisotropic compressibility by a nitrogen dimer Reviewed

    Sasaki, T; Yamamoto, T; Asano, S; Niwa, K; Hasegawa, M

    DALTON TRANSACTIONS   Vol. 52 ( 2 ) page: 469 - 475   2023.1

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Dalton Transactions  

    A novel high-pressure molybdenum nitride phase, Mo3N5, was synthesized at above 45 GPa via a nitridation reaction of molybdenum with nitrogen under high pressure using a laser-heated diamond anvil cell. Mo3N5, having an N-N dimer and 7-coordinated Mo sites, crystallizes in an orthorhombic structure with a space group of Cmcm (No. 63) without other prototype structures. The refined lattice parameters for Mo3N5 were a = 2.86201(2) Å, b = 7.07401(6) Å, and c = 14.59687(13) Å. The DFT enthalpy calculation suggested that Mo3N5 is a high-pressure stable phase, which is also consistent with an increasing coordination number compared to ambient- and low-pressure phases. The zero-pressure bulk modulus of Mo3N5 was determined to be K0 = 328(4) GPa with K′0 = 10.1(6) by the fitting for the compression curve, which is almost consistent with the theoretical E-V curve and elastic stiffness constants. The compressibility of Mo3N5 has axial anisotropy corresponding to the N-N dimer direction in the crystal structure.

    DOI: 10.1039/d2dt03433f

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  9. Ultra-High-Pressure Synthesis of Transition Metal – Nitrogen Binary Compounds

    NIWA Ken, ASANO Shuto, CHANG Chung-Ching, SASAKI Takuya, HASEGAWA Masashi

    The Review of High Pressure Science and Technology   Vol. 33 ( 1 ) page: 26 - 33   2023

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:The Japan Society of High Pressure Science and Technology  

    <p>The recent development of high-pressure experimental techniques combined with advanced characterization and analytical methods allows us to reveal the crystal chemistry of the transition metal-nitrogen binary compounds up to the megabar pressure regime. Novel early transition metal-nitrogen compounds, VN<sub>2</sub>, Nb<sub>2</sub>N<sub>3</sub>, and MoC-type WN<sub>0.6</sub>, have been synthesized by using a laser-heated diamond-anvil cell or DIA-type high-pressure apparatus. In addition to conventional high-pressure <i>in-situ</i> X-ray diffraction measurements, the low-temperature thermal expansion behavior and the valance state of transition metal ions of these newly synthesized compounds were revealed. In this article, the details of our experiments, and recent progress in high-pressure synthesis and crystal chemistry of transition metal nitrogen binary compounds are reviewed.</p>

    DOI: 10.4131/jshpreview.33.26

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  10. High-pressure polycrystalline thin-film synthesis and semiconducting property of platinum pernitride Reviewed

    Ken Niwa, Tomoki Iizuka, Masashi Kurosawa, Yuto Nakamura, Hubert Okadome Valencia, Hideo Kishida, Osamu Nakatsuka, Takuya Sasaki, Nico Alexander Gaida, Masashi Hasegawa

    AIP Advances   Vol. 12 ( 5 ) page: 055318 - 055318   2022.5

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:AIP Publishing  

    A polycrystalline platinum pernitride (PtN<sub>2</sub>) thin-film was successfully synthesized via nitridation of a platinum thin-film deposited on α-Al<sub>2</sub>O<sub>3</sub> substrate at the pressure of ∼50 GPa by using the laser-heated diamond anvil cell. The current–voltage characteristic and optical reflectance of the synthesized PtN<sub>2</sub> thin-film were measured under ambient conditions. Combined with first-principles calculations, these experimental results have revealed that PtN<sub>2</sub> exhibits semiconducting property with a bandgap of ∼2 eV. This high-pressure thin-film synthesis technique could also be applied for revealing the physical properties of other novel pernitrides synthesized under ultra-high pressure, which can offer new insights into the physical properties and functionality of the pernitrides and related nitrides.

    DOI: 10.1063/5.0090089

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  11. Synchrotron-Radiation Infrared Microspectroscopy of Marcasite-Type NiN<sub>2</sub> Reviewed

    Soda, K; Kawada, T; Niwa, K; Hasegawa, M; Ikemoto, Y

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 91 ( 4 )   2022.4

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:Journal of the Physical Society of Japan  

    The electronic structure of the marcasite-type NiN2, newly synthesized under high pressures and high temperatures, was investigated using synchrotron-radiation infrared (IR) microspectroscopy and first-principles calculations based on the density functional theory (DFT). The IR spectrum of the marcasite-type NiN2 showed characteristic low reflectance of the semiconductor with spectral features probably due to defects or lattice vibrations and free carriers. The effective free-carrier concentration in the marcasite-type NiN2 was estimated by fitting a Drude-Lorentz model for the optical response to be 1024-25 m-3, much less than those of normal metals (1028-29 m-3) and comparable to the estimated concentration of the thermally-excited carrier in the conduction band. The DFT predictions could semi-quantitatively explain the experimental findings; at 36 GPa, the marcasite-type NiN2 had a narrow gap between the Ni 3d aσ bands split in the distorted octahedral coordination of N neighbors.

    DOI: 10.7566/JPSJ.91.044702

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  12. High pressure synthesis and the valence state of vanadium ions for the novel transition metal pernitride, CuAl<sub>2</sub>-type VN<sub>2</sub> Reviewed

    Asano, S; Niwa, K; Sasaki, T; Gaida, NA; Hasegawa, M

    DALTON TRANSACTIONS   Vol. 51 ( 7 ) page: 2656 - 2659   2022.2

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Dalton Transactions  

    A novel transition metal pernitride, CuAl2-type VN2, has been synthesized at a pressure above 73.3 GPa. The bulk modulus has been determined to be K0 = 347(12) GPa. By hard X-ray absorption spectrum measurements of VN2, the valence state of transition metal ions in pernitrides has been for the first time experimentally reported.

    DOI: 10.1039/d1dt04310b

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  13. Crystal Growth of Novel Materials under Ultra-High Pressure and Temperature Reviewed

    Hasegawa Masashi, Sasaki Takuya, Gaida Nico A, Niwa Ken

    Journal of the Japanese Association for Crystal Growth   Vol. 49 ( 2 ) page: n/a   2022

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    Language:Japanese   Publishing type:Research paper (scientific journal)   Publisher:The Japanese Association for Crystal Growth  

    <p>  Pressure is one of the thermodynamic parameters together with the temperature to control the stability of materials. Ultra-high pressure in GPa ~ Mbar regions allows us to obtain novel materials and crystals. This review shows two crystal growth systems under ultra-high pressure and high temperature are shown in the first part, i.e. multi-anvil large press and laser-heating diamond anvil cell systems. In the second parts, our recent research results of crystal growth by solution growth techniques using these two systems are described including novel incompressible crystals, high aspect-ratio nanowires and rectangular hollow crystals of metal nitrides and oxides.</p>

    DOI: 10.19009/jjacg.49-2-02

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  14. Pressure-Tunable Crystal Structure and Magnetic Transition Temperature of the Nowotny Chimney-Ladder CrGeγ Phase Reviewed

    Sasaki, T; Noda, K; Gaida, NA; Niwa, K; Hasegawa, M

    INORGANIC CHEMISTRY   Vol. 60 ( 19 ) page: 14525 - 14529   2021.10

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Inorganic Chemistry  

    A Nowotny chimney-ladder (NCL) chromium germanide (CrGeγ) with varying compositions has been synthesized under high pressure. Crystal structure parameters of the NCL CrGeγ have been calculated by Le Bail refinement based on the superspace group. The refined γof CrGeγ increases with the synthesis pressure, indicating an increasing Ge content. The NCL CrGeγ phases are ferromagnetic at T = 2 K regardless of their composition, and the magnetic transition temperature (TC) increases when the γbecomes higher. It is noteworthy that CrGe1.763 and CrGe1.774 synthesized at P = 10 and 14 GPa have magnetic transition temperatures of T = 295 and 333 K above room temperature, respectively. Surprisingly, the magnetic transition temperature has changed by δTC = 270 K, although the γvalues of the raw material and the sample synthesized at P = 14 GPa differ by only δγ= 0.05, corresponding to an atomic concentration of 0.62 atom %. The synthesis pressure acts as an essential parameter in tuning the composition of the NCL phase. Accordingly, the high-pressure synthesis may significantly control several physical characteristics of NCL phases by utilizing compositional and structural modulation.

    DOI: 10.1021/acs.inorgchem.1c01887

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  15. Crystal and Electronic Structure of U<sub>7</sub>Te<sub>12</sub>-Type Tungsten Nitride Synthesized under High Pressure Reviewed

    Chang, CC; Sasaki, T; Gaida, NA; Niwa, K; Hasegawa, M

    INORGANIC CHEMISTRY   Vol. 60 ( 17 ) page: 13278 - 13283   2021.9

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Inorganic Chemistry  

    Tungsten nitride continues to drive fundamental interests because of its potential as a functional compound, which combines features such as high hardness together with thermal, chemical, and wear resistance. Here, we report a novel tungsten nitride phase synthesized from MoC-type WN0.6 and molecular nitrogen after laser irradiation at P = 70 GPa in a diamond anvil cell. This novel phase is quenchable at ambient pressure and determined to be U7Te12-type tungsten nitride and crystallizes in the hexagonal space group (P6) having lattice parameters of a = 8.2398(3) Å, c = 2.94948(14) Å, and V = 173.423(13) Å3. Tungsten atoms are coordinated to eight and nine nitrogen atoms, higher than previously reported tungsten nitrides. The bulk modulus is determined to be K0 = 312 (5) GPa (K0′ = 4.0 fixed), and DFT calculations predict that U7Te12-type W7N12 has a metallic nature.

    DOI: 10.1021/acs.inorgchem.1c01633

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  16. Nitriding synthesis and structural change of phosphorus nitrides at high pressures Reviewed

    Niwa, K; Iijima, Y; Ukita, M; Toda, R; Toyoura, K; Sasaki, T; Matsunaga, K; Gaida, NA; Hasegawa, M

    JOURNAL OF RAMAN SPECTROSCOPY   Vol. 52 ( 5 ) page: 1064 - 1072   2021.5

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Journal of Raman Spectroscopy  

    The phase stability of γ-P3N5 and the possible formation of new phosphorus nitrides were investigated via high-pressure in situ Raman spectroscopy, X-ray diffraction measurements, and first-principles calculations up to approximately 80 GPa. In this study, γ-P3N5 was synthesized via the direct nitridation of black phosphorus at a pressure approximately above 12 GPa. The Raman spectrum, bulk modulus (K0 = 130.27(43) GPa), and compression behaviors (order of axial compressibility: βc > βa > βb) were experimentally measured for the first time. These experimental results were in good agreement with those of first-principles calculations. Our high-pressure in situ measurements and first-principles calculations revealed that γ-P3N5 persisted up to 80 GPa at room temperature. The compression of γ-P3N5 proceeded with the folding of the layer consisting of the corner- and edge-sharing PN4 and PN5. The present findings indicate that the P–N bonding with a low coordination number (PN4 and PN5) is preferable and stabilized for phosphorus nitride over a wide pressure range. However, laser heating between 67 and 70 GPa in the presence of nitrogen resulted in the formation of new PxNy, which included the possibility of a new high-pressure P3N5 phase. The Raman scattering measurements along with the decompression demonstrated that the local structure of the newly synthesized PxNy metastably persisted at atmospheric pressure. The present experimental and theoretical studies on phosphorus nitrides offer new insights into the high-pressure behaviors of covalent compounds consisting of highly coordinated polyhedra.

    DOI: 10.1002/jrs.6079

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  17. Electronic Structures of Transition-Metal Pernitrides Studied Using X-ray Absorption and Photoelectron Spectroscopy Reviewed

    Soda Kazuo, Kato Daiki, Komabuchi Mai, Terabe Toshiki, Takayama Shin, Ibaragi Toshiki, Kato Masahiko, Niwa Ken, Hasegawa Masashi, Takakura Shoichi, Nakatake Masashi

    Journal of the Physical Society of Japan   Vol. 90 ( 4 ) page: 44710 - 44710   2021.4

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Physical Society of Japan  

  18. Electronic Structures of Transition-Metal Pernitrides Studied Using X-ray Absorption and Photoelectron Spectroscopy Reviewed

    Soda Kazuo, Kato Daiki, Komabuchi Mai, Terabe Toshiki, Takayama Shin, Ibaragi Toshiki, Kato Masahiko, Niwa Ken, Hasegawa Masashi, Takakura Shoichi, Nakatake Masashi

    Journal of the Physical Society of Japan   Vol. 90 ( 4 ) page: 44710 - 44710   2021.4

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Physical Society of Japan  

  19. Phase relations and thermoelasticity of magnesium silicide at high pressure and temperature Reviewed

    Nico Alexander Gaida, Ken Niwa, Takuya Sasaki, Masashi Hasegawa

    The Journal of Chemical Physics   Vol. 154 ( 14 ) page: 144701   2021.4

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/5.0044648

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  20. Crystal and Electronic Structures of MoSi2-Type CrGe2 Synthesized under High Pressure Reviewed

    Takuya Sasaki, Kota Kanie, Tatsuya Yokoi, Ken Niwa, Nico Alexander Gaida, Katsuyuki Matsunaga, Masashi Hasegawa

    Inorganic Chemistry   Vol. 60 ( 3 ) page: 1767 - 1772   2021.2

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:American Chemical Society (ACS)  

    DOI: 10.1021/acs.inorgchem.0c03240

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  21. Elasticity of nanocrystalline kyanite at high pressure and temperature from ultrasonic and synchrotron X-ray techniques Reviewed

    Nico A. Gaida, Steeve Gréaux, Yoshio Kono, Hiroaki Ohfuji, Hideharu Kuwahara, Norimasa Nishiyama, Oliver Beermann, Takuya Sasaki, Ken Niwa, Masashi Hasegawa

    Journal of the American Ceramic Society   Vol. 104 ( 1 ) page: 635 - 644   2021.1

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    Material properties, such as elasticity data at wide-ranging conditions of pressure and temperature, attract increasing attention for material and earth sciences. In particular, polycrystalline ceramics for next-generation photonic applications are nowadays fabricated by advanced syntheses techniques operating under elevated pressures and temperatures. Herein, the elastic properties of a synthetic transparent and reinforced aluminosilicate nanoceramic composed of triclinic kyanite with minor amounts of trigonal α-alumina crystals are investigated using in situ synchrotron X-ray diffraction and ultrasonic techniques at high-pressure (up to 11 GPa) and high-temperature (300-1500 K) conditions. This not only enables the determination of the equation of state (EoS) parameters by applying the pressure-volume-temperature (P-V-T) data to the high-temperature Birch-Murnaghan EoS but also yields the elastic moduli together with their P and T derivatives from the fit of the compressional and shear wave velocities to a finite strain EoS: KS0,300 = 186(2) GPa, K′S0,300 = 7.2(6), (∂KS0,300/∂T)P = −0.023(2) GPa K−1, G0,300 = 125(1) GPa G′0,300 = 2.3(2), (∂G0,300/∂T)P = −0.017(1) GPa K−1. On the basis of our acquired results, we propose to predict the elastic moduli of aluminosilicate ceramics by a linear function of the ratio of AlO6 octahedra and SiO4 tetrahedra within the constituting phases.

    DOI: 10.1111/jace.17464

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  22. Thermal Expansion of Incompressible U2S3-Type Nb(2)N(3 )Synthesized in a Diamond Anvil Cell

    Asano Shuto, Niwa Ken, Sasaki Takuya, Gaida Nico Alexander, Hasegawa Masashi

    INORGANIC CHEMISTRY   Vol. 59 ( 12 ) page: 7915 - 7918   2020.6

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:American Chemical Society (ACS)  

    DOI: 10.1021/acs.inorgchem.0c01057

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  23. Crystal structures and electronic properties of Sn3N4 polymorphs synthesized via high-pressure nitridation of tin

    Niwa Ken, Inagaki Tomoya, Ohsuna Tetsu, Liu Zheng, Sasaki Takuya, Gaida Nico Alexander, Hasegawa Masashi

    CRYSTENGCOMM   Vol. 22 ( 20 ) page: 3531 - 3538   2020.5

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    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d0ce00210k

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  24. Hydrogen Depth-profiles in Nb Hydrides Formed in Supercritical Water Reviewed

    Soda Kazuo, Sugiura Shinya, Yamaguchi Kanta, Kato Masahiko, Niwa Ken, Hasegawa Masashi, Suzuki Kohtaku, Ishigami Ryoya, Ikenaga Eiji

    e-Journal of Surface Science and Nanotechnology   Vol. 18   page: 152-158   2020.4

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    DOI: 10.1380/ejssnt.2020.152

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  25. Nanowire crystals of tantalum nitride grown in ammonium halide fluxes at high pressures

    Gaida Nico Alexander, Sasaki Takuya, Liu Zheng, Niwa Ken, Hirozawa Masaki, Ohsuna Tetsu, Hasegawa Masashi

    APPLIED PHYSICS LETTERS   Vol. 116 ( 12 )   2020.3

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    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.1063/1.5140856

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  26. Microstructural effects on hardness and optical transparency of birefringent aluminosilicate nanoceramics Nico Reviewed

    Gaida, Nico A. Nishiyama, Norimasa Beermann, Oliver Schürmann, Ulrich Masuno, Atsunobu Giehl, Christopher Niwa, Ken Hasegawa, Masashi Bha, Shrikant Farla, Robert Kienle, Lorenz

    International Journal of Ceramic Engineering & Science   Vol. 2 ( 2 ) page: 76 - 82   2020.3

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    DOI: 10.1002/ces2.10036

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  27. Synthesis of platinum-group-metal dinitrides by direct nitridation under ultra-high pressures Reviewed

    HASEGAWA Masashi, NIWA Ken

    Oyo Buturi   Vol. 89 ( 2 ) page: 87 - 91   2020.2

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    <p>It was assumed that platinum-group-metals neither react with nitrogen nor form their nitrides at ambient pressure.However, ultra-high-pressure conditions of more than several dozen GPa have recently made it possible to synthesize their dinitrides by a direct nitridation. This short communication reports on new worldwide trends f of novel metal(M) nitride studies, such as MN<sub>2</sub>, M<sub>2</sub>N<sub>3</sub>, M<sub>3</sub>N<sub>4</sub>, particularly platinum-group-metal dinitrides, which can be synthesized only under ultra-high-pressures. The first section deals with an ultra-high-pressure synthesis technique using a diamond anvil cell combined with an infra-red-laser heating system. The next section describes their synthesis, phase stability, crystal structure, and physical properties. Other novel transition-metal dinitrides are also introduced briefly, particularly focusing on the growth of CrN<sub>2</sub> single crystals, which exhibit the first and only success among novel metal dinitrides.</p>

    DOI: 10.11470/oubutsu.89.2_87

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  28. High-Pressure Synthesis and Crystal Structure of MoC-Type Tungsten Nitride by Nitridation with Ammonium Chloride

    Sasaki Takuya, Ikoma Takahide, Sago Kazuki, Liu Zheng, Niwa Ken, Ohsuna Tetsu, Hasegawa Masashi

    INORGANIC CHEMISTRY   Vol. 58 ( 24 ) page: 16379 - 16386   2019.12

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    DOI: 10.1021/acs.inorgchem.9b01945

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  29. Hydrogen-Storing Salt NaCl(H-2) Synthesized at High Pressure and High Temperature

    Matsuoka Takahiro, Muraoka Shu, Ishikawa Takahiro, Niwa Ken, Ohta Kenji, Hirao Naohisa, Kawaguchi Saori Imada, Ohishi Yasuo, Shimizu Katsuya, Sasaki Shigeo

    JOURNAL OF PHYSICAL CHEMISTRY C   Vol. 123 ( 41 ) page: 25074 - 25080   2019.10

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    DOI: 10.1021/acs.jpcc.9b06639

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  30. High-Pressure Synthesis and Phase Stability of Nickel Pernitride

    Niwa Ken, Fukui Riku, Terabe Toshiki, Kawada Takuya, Kato Daiki, Sasaki Takuya, Soda Kazuo, Hasegawa Masashi

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY   Vol. 2019 ( 33 ) page: 3753 - 3757   2019.9

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    DOI: 10.1002/ejic.201900489

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  31. Lithium ionic conductivities of alpha-LiBO2 with two-dimensional Li-Li networks and gamma-LiBO2 with three-dimensional ones synthesized under high pressure Reviewed

    Hirose Eiichi, Kataoka Kunimitsu, Nagata Hiroshi, Akimoto Junji, Sasaki Takuya, Niwa Ken, Hasegawa Masashi

    JOURNAL OF SOLID STATE CHEMISTRY   Vol. 274   page: 100 - 104   2019.6

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    © 2019 Elsevier Inc. Lithium ionic conductivities of two LiBO 2 polymorphs, i.e. the same composition Li borates: α-LiBO 2 and γ-LiBO 2 , which are ambient and high-pressure phases, have been measured by the AC impedance method between 450 and 520 K using their high-density polycrystalline samples synthesized under high pressures. It is found the intra-grain and total conductivities of the γ-LiBO 2 have been measured for the first time and be of the order 10 −5 ∼ 10 −6 Scm −1 and 10 −6 Scm −1 , respectively, both of which are higher in whole measured temperature range than those of the α-LiBO 2 . The higher lithium ionic conductivities of the former are discussed from the viewpoints of local structure and Li ion network in the crystal structures of the α-LiBO 2 and γ-LiBO 2 .

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  32. High-pressure synthesis, crystal growth, and compression behavior of hexagonal CrN2 having one-dimensionally aligned nitrogen dimer Reviewed

    Niwa Ken, Yamamoto Takurou, Sasaki Takuya, Hasegawa Masashi

    PHYSICAL REVIEW MATERIALS   Vol. 3 ( 5 )   2019.5

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    DOI: 10.1103/PhysRevMaterials.3.053601

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  33. Infrared spectroscopy on electronic structures of platinum-group metal pernitrides MN2 (M = Ru, Rh, Ir, and Pt) Reviewed

    Soda Kazuo, Komabuchi Mai, Maeguchi Keisuke, Kato Masahiko, Terabe Toshiki, Niwa Ken, Hasegawa Masashi, Ikemoto Yuka, Okamura Hidekazu

    PHYSICA B-CONDENSED MATTER   Vol. 558   page: 54 - 58   2019.4

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    The electronic structures of platinum-group metal pernitrides MN2 (M = Ru, Rh, Ir, and N) were investigated via synchrotron radiation infrared spectroscopy and first-principles calculations. Measured reflectance spectra of marcasite-type RuN2 and RhN(2 )showed Drude-like responses, approaching 1 as the photon energy was decreased, whereas reflectance of arsenopyrite-type IrN2 and pyrite-type PtN2 became similar to 0.3 in the low photon energy region with a few features. These findings agreed well with the predictions of the metallic nature of marcasite-type RuN2 and RhN2 and the semiconducting properties of arsenopyrite-type IrN2 and pyrite-type PtN2 , respectively. The measured reflectance spectra were also reasonably consistent with the calculated optical responses. The band gaps of IrN2 and PtN2 were estimated to be 0.8 and 2.1 eV, respectively, via first-principles calculation with a modified Becke-Johnson (MBJ) potential for the exchange potential.

    DOI: 10.1016/j.physb.2019.01.017

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  34. High-Pressure Synthesis, Crystal Chemistry, and Ionic Conductivity of a Structural Polymorph of Li3BP2O8 Reviewed

    Hirose Eiichi, Kataoka Kunimitsu, Nagata Hiroshi, Akimoto Junji, Sasaki Takuya, Niwa Ken, Hasegawa Masashi

    INORGANIC CHEMISTRY   Vol. 57 ( 24 ) page: 15048 - 15050   2018.12

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    © 2018 American Chemical Society. A new structural polymorph of Li 3 BP 2 O 8 has been successfully synthesized via a solid-state reaction between Li 3 PO 4 and BPO 4 at 4 GPa and 600 °C. The high-pressure phase of Li 3 BP 2 O 8 (HP-Li 3 BP 2 O 8 ) was found to crystallize in monoclinic symmetry with the cell parameters of a = 8.57010(4) Å, b = 11.11812(5) Å, c = 5.55380(3) Å, and β = 97.7269(3)° [space group P2 1 /a (No. 14)]. HP-Li 3 BP 2 O 8 has a new crystal structure that has not been reported so far. The total ionic conductivities measured for the polycrystalline sample by alternating-currrent impedance were 3.4 × 10 -7 and 2.1 × 10 -6 S/cm at 399 and 456 K, respectively. The lithium ionic conductivity of HP-Li 3 BP 2 O 8 was higher than that of the low-pressure phase Li 3 BP 2 O 8 in the temperature range of 375-456 K. This is caused by the difference in the dimensions of the lithium arrangements between LP- and HP-Li 3 BP 2 O 8 .

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  35. Structural stability of the Li-ion conductor Li7La3Zr2O12 investigated by high-pressure in-situ X-ray diffraction and Raman spectroscopy

    Hirose Eiichi, Niwa Ken, Kataoka Kunimitsu, Akimoto Junji, Hasegawa Masashi

    MATERIALS RESEARCH BULLETIN   Vol. 107   page: 361 - 365   2018.11

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    © 2018 Elsevier Ltd The high-pressure behavior of Li7La3Zr2O12 (LLZO) with a garnet-related structure has been investigated for the first time by high pressure in situ X-ray diffraction measurements and Raman spectroscopy using a diamond anvil cell. It was found that the tetragonal LLZO transforms to the high-pressure cubic phase (HP-c-LLZO) at 71.8 GPa in a N2 medium and at 25.8 GPa in the absence of pressure mediums. Uniaxial compression in the absence of pressure mediums induced the phase transition at much lower pressures than in the hydrostatic case when N2 was used as the pressure medium. High pressure in situ Raman spectroscopy suggested that the Li coordination in HP-c-LLZO was different from that reported in cubic LLZO, which had been stabilized by doping Al at ambient pressure and room temperature.

    DOI: 10.1016/j.materresbull.2018.07.034

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  36. Valence-band electronic structures of high-pressure-phase PdF2-type platinum-group metal dioxides MO2 (M = Ru, Rh, Ir, and Pt)

    Kazuo Soda, Daichi Kobayashi, Tatsuya Mizui, Masahiko Kato, Yuichi Shirako, Ken Niwa, Masashi Hasegawa, Masaki Akaogi, Hiroshi Kojitani, Eiji Ikenaga, Takayuki Muro

    Journal of the Physical Society of Japan   Vol. 87 ( 4 )   2018.4

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    The valence-band electronic structures of high-pressure-phase PdF2-type (HP-PdF2-type) platinum-group metal dioxides MO2 (M = Ru, Rh, Ir, and Pt) were studied by synchrotron radiation photoelectron spectroscopy and first-principles calculations. The obtained photoelectron spectra for HP-PdF2-type RuO2, RhO2, and IrO2 agree well with the calculated valence-band densities of states (DOSs) for these compounds, indicating their metallic properties, whereas the DOS of HP-PdF2-type PtO2 (calculated in the presence and absence of spin–orbit interactions) predicts that this material may be metallic or semimetallic, which is inconsistent with the electric conductivity reported to date and the charging effect observed in current photoelectron measurements. Compared with the calculated results, the valence-band spectrum of PtO2 appears to have shifted toward the high-binding-energy side and reveals a gradual intensity decrease toward the Fermi energy EF, implying a semiconductor-like electronic structure. Spin-dependent calculations predict a ferromagnetic ground state with a magnetization of 0.475 μB per formula unit for HP-PdF2-type RhO2

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  37. High pressure in-situ synthesis and physical properties of Cr3C2-Ni cermets International coauthorship

    Wenyan Zhai, Yimin Gao, Liang Sun, Yiran Wang, Ken Niwa, Masashi Hasegawa

    CERAMICS INTERNATIONAL   Vol. 43 ( 18 ) page: 17202 - 17205   2017.12

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    A novel Cr3C2-Ni cermets were successfully in-situ synthesized with Cr, C and Ni (20 wt%) mixed-powder at 1100 degrees C under 0-6 GPa isostatic pressure using a small-sized cubic-type multi-anvil press apparatus. High purity Cr3C2 phase was generated in the cermets. Comparing with the conventional and reactive sintering, the sintering temperature and the average grain size of Cr3C2 decreased by 200 degrees C and 50%, respectively. The physical properties, normalized lattice parameters and volumes of Cr3C2 20 wt%Ni cermet as a function of pressure had been studied both experimentally and by first-principles calculations for the first time.

    DOI: 10.1016/j.ceramint.2017.09.145

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  38. Pyrite form of group-14 element pernitrides synthesized at high pressure and high temperature

    K. Niwa, H. Ogasawara, M. Hasegawa

    DALTON TRANSACTIONS   Vol. 46 ( 30 ) page: 9750 - 9754   2017.8

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    The chemical reaction of group-14 elements with molecular nitrogen at pressures above 60 GPa successfully leads to the formation of pyrite-type pernitrides. These new crystalline group-14 elemental pernitrides were found to show a bulk modulus higher than the other known group-14 elemental nitrides. Our results offer significant new progress in the solid-state chemistry of nitrides.

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  39. Microbeam Hard X-ray Photoemission Study on Platinum-Group Metal Pernitrides

    Kazuo Soda, Tatsuya Mizui, Mai Komabuchi, Masahiko Kato, Toshiki Terabe, Kentaro Suzuki, Ken Niwa, Yuichi Shirako, Masashi Hasegawa, Masaki Akaogi, Hiroshi Kojitani, Eiji Ikenaga

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN   Vol. 86 ( 6 ) page: 64804 - 64804   2017.6

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    Using microbeam hard X-ray photoelectron spectroscopy, we clarified the valence-band electronic structures and chemical states of platinum-group metal (Ru, Ir, and Pt) pernitrides, which have been synthesized in supercritical nitrogen fluid under extremely high pressures and temperatures. Their nitrogen contents relative to the platinum-group metal are estimated to be 2 from the photoemission intensity, which is consistent with the studies reported to date. The observed valence-band structures agree quite well with theoretically predicted structures for the pyrite-type PtN2, arsenopyrite-type IrN2, and marcasite-type RuN2. The origin of their extremely large bulk moduli is discussed based on the current results of the valence-band structures and core-level chemical shifts.

    DOI: 10.7566/JPSJ.86.064804

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  40. Highly Coordinated Iron and Cobalt Nitrides Synthesized at High Pressures and High Temperatures

    Ken Niwa, Toshiki Terabe, Daiki Kato, Shin Takayama, Masahiko Kato, Kazuo Soda, Masashi Hasegawa

    INORGANIC CHEMISTRY   Vol. 56 ( 11 ) page: 6410 - 6418   2017.6

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    Highly coordinated iron and cobalt nitrides were successfully synthesized via direct chemical reaction between a transition metal and molecular nitrogen at pressures above approximately 30 GPa using a laser-heated diamond anvil cell. The synthesized novel transition metal nitrides were found to crystallize into the NiAs-type or marcasite-type structure. NiAs-type FeN could be quenched at ambient pressure, although it was gradually converted to the ZnS-type structure after the pressure was released. On the other hand, CoN was recovered with ZnS-type structure through a phase transition from NiAs-type structure at approximately a few gigapascals during decompression. Marcasite-type CoN2 was also synthesized at pressures above approximately 30 GPa. High-pressure in situ X-ray diffraction measurement showed that the zero-pressure bulk modulus of marcasite-type CoN2 is 216(18) GPa, which is comparable to that of RhN2. This indicates that the interatomic distance of the N-N dimer in marcasite-type CoN2 is short because of weak orbital interaction between cobalt and nitrogen atoms, as in RhN2. Surprisingly, a first-principles electronic band calculation suggests that the NiAs-type FeN and CoN and marcasite-type CoN2 exhibit metallic characteristics with magnetic moments of 3.4, 0.6, and 1.2 mu(B), respectively. The ferromagnetic NiAs-type structure originates from the anisotropic arrangement of transition atoms stacked along the: c axis.

    DOI: 10.1021/acs.inorgchem.7b00516

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  41. Synthesis, crystal structure and phase transition of a Xe-N-2 compound at high pressure: experimental indication of orbital interaction between xenon and nitrogen

    K. Niwa, F. Matsuzaki, M. Hasegawa

    PHYSICAL CHEMISTRY CHEMICAL PHYSICS   Vol. 19 ( 1 ) page: 59 - 63   2017.1

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    The van der Waals compound Xe(N-2)(2) with a C15 Laves structure was successfully synthesised at pressures greater than 4.4 GPa. We found that, at 10 GPa, the structure reversibly transforms from a cubic to a tetragonal phase. Further compression results in changes of Xe-N compound, which could result in the enhancement of orbital interactions between the xenon and nitrogen atoms.

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  42. High-Pressure Synthesis and Magnetic Behavior of A-Site Columnar-Ordered Double Perovskites, LnMn(Ga0.5Ti0.5)(2)O-6 (Ln = Sm, Gd)

    Gen Shimura, Ken Niwa, Yuichi Shirako, Masashi Hasegawa

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY   Vol. 2017 ( 4 ) page: 835 - 839   2017.1

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    A-site columnar-ordered double perovskites, LnMn(Ga0.5Ti0.5)(2)O-6 (Ln = Sm, Gd), were successfully synthesized under high pressure and high temperature (6 GPa, 1375 K). From the synchrotron powder X-ray diffraction patterns, all of the diffraction peaks can be indexed by the P4(2)/nmc space group with lattice parameters a, c approximate to 2a(p) (a(p): primitive cubic perovskite lattice) and no ordering of the B-site cations. Rietveld analysis of the synchrotron powder X-ray diffraction patterns and Curie-Weiss fitting of their magnetizations reveal that the ionic formulae of these perovskites are Ln(3+) Mn2+(Ga0.53+Ti0.54+)(2)O-6(2-). SmMn(Ga0.5Ti0.5)(2)O-6 shows canted-antiferromagnetic behavior, whereas GdMn(Ga0.5Ti0.5)(2)O-6 exhibits two different magnetic states at low temperature depending on the applied magnetic field and shows an unusual magnetization curve. These magnetic behaviors originate by decreasing the antiferromagnetic interaction by substituting Ga3+(d(10)) for Ti4+(d(0)) and by decreasing the ferromagnetic interaction between columnar-ordered Ln(3+) and Mn2+.

    DOI: 10.1002/ejic.201601392

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  43. Microbeam hard X-ray photoelectron and ion-beam analyses of Nb hydrides formed in supercritical water

    Kazuo Soda, Shinya Sugiura, Kanta Yamaguchi, Masahiko Kato, Ken Niwa, Masashi Hasegawa, Kohtaku Suzuki, Ryoya Ishigami, Eiji Ikenaga

    International Symposium on Atomic Level Characterizations for New Materials and Devices ‘17 Proceedings     2017

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  44. High pressure stability and ambient metastability of marcasite-type rhodium pernitride Reviewed

    K. Niwa, T. Terabe, K. Suzuki, Y. Shirako, M. Hasegawa

    Journal of Applied Physics   Vol. 119   page: 065901   2016

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  45. Multicomponent A-site ordered perovskite BiMn3(Fe0.25Ti0.75)4O12: High-pressure synthesis, crystal chemistry and magnetic behavior Reviewed

    G. Shimura, K. Niwa, Y. Shirako, S. Muto, K. Kusaba, M. Hasegawa

    Solid State Communications   Vol. 234-235   page: 40-44   2016

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    DOI: doi.org/10.1016/j.ssc.2016.03.004

  46. Molecular routes syntheses of graphite-like C-N compounds with various N/C ratios in high pressure and temperature Reviewed

    T. HORIBE, K. KUSABA, K. NIWA, M. HASEGAWA, K. YASUDA, R. ISHIGAMI

    Journal of the Ceramic Society of Japan   Vol. 124 ( 10 ) page: 1013-1016   2016

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    DOI: 10.2109/jcersj2.16123

  47. High-pressure synthesis and relationship between A-site ordering and local structure of multicomponent perovskites(Ln0.25Mn0.75) (Al0.25Ti0. 75)O3, Ln=La, Pr, Nd, Sm, Gd, Tb, Dy, Y Reviewed

    G. Shimura, Y. Shirako, K. Niwa, M. Hasegawa

    Journal of Solid State Chemistry   Vol. 242   page: 55-62   2016

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  48. Angle-resolved hard x-ray photoemission study of Nb hydride formation in high-pressure supercritical water Reviewed

    Kazuo Soda, Hiroki Kondo, Kanta Yamaguchi, Masahiko Kato, Tatsuhito Shirak, Ken Niwa, Keiji Kusaba, Masashi Hasegawa, Kozina Xeniya, Eiji Ikenaga

    Journal of Alloys and Compounds   Vol. 643   page: 195-200   2015

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  49. Growth of rectangular hollow tube crystals with rutile-type structure in supercritical fluids Reviewed

    K. Niwa, H. Ikegaya, T. Taguchi, S. Muto, T. Tokunaga and M. Hasegawa

    Journal of Physics: Conference Series (JPCS)   Vol. 500   page: 022007   2014

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  50. High pressure synthesis of marcasite-type rhodium pernitride Reviewed International coauthorship

    K. Niwa, D. Dzivenko, K. Suzuki, R. Riedel, I. Troyan, M. Eremets and M. Hasegawa

    Inorganic Chemistry   Vol. 53   page: 697-699   2014

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  51. Novel material synthesis using laser-heated diamond anvil cell Invited Reviewed

      Vol. 24   page: 178-187   2014

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  52. Discovery of the last remaining binary platinum group pernitride RuN2 Reviewed

    K. Niwa, K. Suzuki, S. Muto, K. Tatsumi, K. Soda, T. Kikegawa and M. Hasegawa

    Chemistry-A European Journal   Vol. 20 ( 43 ) page: 13885 - 13888   2014

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  53. Argon Solubility in SiO2 Melt under High Pressures : A New Experimental Result using Laser-Heated Diamond-Anvil Cell Reviewed

    K. Niwa, C. Miyakawa, J. Matsuda, T. Yagi

    Earth and Planetary Science Letters   Vol. 363   page: 1-8   2013

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  54. Characterization of Nb Hydrides Synthesized in High-Pressure Supercritical Water by Micro-beam Hard X-ray Photoelectron Spectroscopy Reviewed

    K. Soda, H. Kondo, M. Kato, T. Shiraki, K. Niwa, K. Kusaba, M. Hasegawa, E. Ikenaga

    Journal of Electron Spectroscopy and Related Phenomena   Vol. 186   page: 54-57   2013

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  55. Pressure-induced noble gas insertion into zeolite LTA and its incompressible behaviors at high pressure Reviewed

    K. Niwa, T. Tanaka, M. Hasegawa, T. Okada, T. Yagi, K. Kikegawa

    MICROPOROUS AND MESOPOROUS MATERIALS   Vol. 182   page: 191-197   2013

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  56. Effects of Sn2+ Ion Size on Sn Doped SrTiO3 Reviewed

    S. Suzuki, A. Honda, K. Suzuki, S. Higai, A. Ando, K. Niwa, M. Hasegawa

    Japanese Journal of Applied Physics   Vol. 52   page: 09KC04   2013

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  57. In-situ observation of shear stress-induced perovskite to post-perovskite phase transition in CaIrO3 and the development of its deformation texture in a diamond-anvil cell up to 30 GPa Reviewed

    K. Niwa, N. Miyajima, Y. Seto, K. Ohgushi, H. Gotou, T. Yagi

    Physics of the Earth and Planetary Interiors   Vol. 194-195   page: 10–17   2012

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  58. High pressure induced water penetration into 3-isopropylmalate dehydrogenase Reviewed

    T. Nagae, T. Kawamura, L. Chavas, K. Niwa, M. Hasegawa, C. Kato, N. Watanabe

    Acta Crystallographica D   Vol. 68   page: 300–309   2012

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  59. B1-to-B2 Structural Transitions in Rock Salt Intergrowth Structures Reviewed

    T. Yamamoto, Y. Kobayashi, T. Okada, T. Yagi, T. Kawakami, C. Tassel, S. Kawasaki, N. Abe, K. Niwa, T. Kikegawa, N. Hirao, M. Takano, H. Kageyama

    Inorg. Chem.   Vol. 50   page: 11787-11794   2011.10

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  60. Growth and optical properties of rectangular hollow tube TiO2 crystals with rutile-type structure Reviewed

    K. Niwa, T. Taguchi, T. Tokunaga, M. Hasegawa

    Crystal Growth & Design   Vol. 11 ( 10 ) page: 4427-4432   2011.8

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  61. Compression behaviors of binary skutterudite CoP3 in noble gases up to 40 GPa at room temperature Reviewed

    K. Niwa, D. Nomichi, M. Hasegawa, T. Okada, T. Yagi, T. Kikegawa

    Inorganic Chemistry   Vol. 50   page: 3281–3285   2011.3

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  62. 超高圧超高温下での超臨界流体を用いた無機化合物の合成と単結晶育成

    長谷川正,丹羽健

    セラミックス   Vol. 46   page: 378-385   2011

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  63. ダイアモンドアンビルセルとレーザー加熱を用いた超高圧超高温超臨界流体中での結晶成長

    長谷川正,丹羽健

    日本結晶成長学会誌   Vol. 38   page: 4-11   2011

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  64. Lattice-preferred orientations in post-perovskite-type MgGeO3 formed by transformations from different pre-phases Reviewed

    T. Okada, T. Yagia, K. Niwa, T. Kikegawa

    Phys. Earth Planet. Int.   Vol. 180 ( 3-4 ) page: 195-202   2010.6

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  65. Submicron rectangular hollow tube crystals of rutile-type GeO2 Reviewed

    K. Niwa, H. Ikegaya, M. Hasegawa, T. Ohsuna, T. Yagi

    J. Crystal Growth   Vol. 312 ( 10 ) page: 1731-1735   2010.5

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  66. Deformation microtextures in CaIrO3 post-perovskite under high stress conditions using a laser-heated diamond anvil cell Reviewed

    N Miyajima, K Niwa, F Heidelbach, T Yagi and K Ohgushi

    Journal of Physics: Conference Series   Vol. 215   page: 012097   2010

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  67. Elasticity of CaIrO3 with perovskite and post-perovskite structure Reviewed

    K. Niwa, T. Yagi, K. Ohgushi

    Phys. Chem. Minerals     page: DOI: 10.1007/s00269-010-0378-z   2010

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

  68. Decomposition of perovskite FeTiO3 into wustite Fe1-xTi0.5xO and orthorhombic FeTi3O7 at high pressure Reviewed

    D. Nishio-Hamane, T. Yagi, M. Ohshiro, K. Niwa, T. Okada, Y. Seto

    Physical Review B   Vol. 82   page: 092103   2010

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    Language:English   Publishing type:Research paper (scientific journal)  

  69. Combining FIB milling and conventional Argon ion milling techniques to prepare high-quality site-specific TEM samples for quantitative EELS analysis of oxygen in molten iron Reviewed

    N. Miyajima, C. Holzapfel, Y. Asahara, L. Dubrovinsky, D.J. Frost, D.C. Rubie, M. Drechsler, K. Niwa, M. Ichihara, T. Yagi

    J. Microsc.   Vol. 238 ( 3 ) page: 200-209   2009.6

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  70. The stability and equation of state for the cotunnite phase of TiO2 up to 70 GPa Reviewed

    D. Nishio-Hamane, A. Shimizu, R. Nakahira, K. Niwa, A. Sano-Furukawa, T. Okada, T. Yagi, T. Kikegawa

    Phys. Chem. Minerals   Vol. 37 ( 3 ) page: 129-136   2009.3

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    Language:English   Publishing type:Research paper (scientific journal)  

  71. Synthesis of Ln nitrides (Ln = Ce, Pr, Gd, Lu) in high pressure and temperature Reviewed

    K. Niwa, M. Hasegawa, T. Yagi

    J. Alloys Compd.   Vol. 477   page: 493–497   2009

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  72. A new high-pressure polymorph of Ti2O3: implication for high-pressure phase transition in sesquioxide Reviewed

    D. Nishio-Hamane, M. Katagiri, K. Niwa, A. Sano-Furukawa, T. Okada, T. Yagi

    High Pressure Research   Vol. 29   page: 379-388   2009

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  73. Solubility of Noble Gas in SiO2 Melt under High Pressure Reviewed

      Vol. 18   page: 44-54   2008

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  74. DACを用いたMgGeO3ポストペロブスカイト相の塑性変形実験と選択配向の観察 Reviewed

    岡田卓,八木健彦,丹羽健

    高圧力の科学と技術   Vol. 18   page: 244-253   2008

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    Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.4131/JSHPREVIEW.18.244

  75. Lattice Preferred Orientation in CaIrO3 Perovskite and Post-Perovskite Formed by the Plastic Deformation Under Pressure Reviewed

    K. Niwa, T. Yagi, K. Ohgushi, S. Merkel, N. Miyajima, T. Kikegawa

    Phys. Chem. Minerals   Vol. 34   page: 679-686   2007

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: doi.org/10.1007/s00269-007-0182-6

  76. Synthesis of new La nitrides at high pressure and temperature Reviewed

    M. Hasegawa, K. Niwa, T. Yagi

    Solid State Commun.   Vol. 141   page: 267-272   2007

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    DOI: doi.org/10.1016/j.ssc.2006.10.032

▼display all

Books 2

  1. 高圧力の科学・技術事典

    ( Role: Contributor)

    朝倉書店  2022.11  ( ISBN:978-4-254-10297-0

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    Language:Japanese

  2. 高圧力の科学・技術事典

    ( Role: Contributor)

    朝倉書店  2022.11  ( ISBN:9784254102970

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    Language:Japanese

Presentations 194

  1. The low temperature thermal expansion behavior of entropy stabilized oxide (MgCoNiCuZn)O International conference

    Chung-Ching Chang, Takuya Sasaki, Nico Alexander Gaida, Ken Niwa, Masashi Hasegawa

    International Collaborative Meeting on Mixed-anion Compounds  2023.3.14 

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    Event date: 2023.3

    Language:English   Presentation type:Poster presentation  

  2. Phase stability and compression behavior of a novel high-pressure phase of manganese mononitride International conference

    Shuto Asano, Ken Niwa, Saori Kawaguchi, Takuya Sasaki, Masashi Hasegawa

    International Collaborative Meeting on Mixed-anion Compounds  2023.3.14 

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    Event date: 2023.3

    Language:English   Presentation type:Poster presentation  

  3. Eu2+賦活高圧相 SrAl4O7 蛍光体の高温高圧合成と蛍光特性

    杉浦 環太,佐々木 拓也,丹羽 健,長谷川 正

    公益社団法人日本セラミックス協会 2023 年年会  2023.3.8 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Poster presentation  

  4. 高圧力合成を利用したチムニー・ラダー相 CrGeγ の組成および磁気転移温度制御

    佐々木 拓也,野田 航希,ガイダニコ アレクサンダー,丹羽 健,長谷川 正

    公益社団法人日本セラミックス協会 2023 年年会  2023.3.9 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Oral presentation (general)  

  5. 窒化炭素系化合物の超高圧合成と相安定性

    丹羽 健,深井 俊史,神 有輝,佐々木 拓也,長谷川 正

    公益社団法人日本セラミックス協会 2023 年年会  2023.3.9 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Oral presentation (general)  

  6. 新規 Fe-Si 系化合物の超高圧合成と結晶構造

    有賀 甚,丹羽 健,佐々木 拓也,長谷川 正

    公益社団法人日本セラミックス協会 2023 年年会  2023.3.8 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Poster presentation  

  7. 高圧下における新規Ta-Sn系化合物の合成

    水野 聖也,佐々木 拓也,丹羽 健,長谷川 正

    日本金属学会2023年春期第172回講演大会  2023.3.7 

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    Event date: 2023.3

    Language:Japanese   Presentation type:Poster presentation  

  8. 超高圧力合成法による新規Cr–Si系化合物の創製と結晶化学

    佐々木 拓也,高野 航一,Gaida Nico Alexander,丹羽 健,長谷川 正

    日本金属学会2023年春期第172回講演大会  2023.3.7 

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    Event date: 2023.3

    Presentation type:Poster presentation  

  9. Thermal Expansion Behavior of the High Entropy Oxide (MgCoNiCuZn)O at Low Temperature International conference

    Chung-Ching Chang, Takuya Sasaki, Nico Alexander Gaida, Ken Niwa, Masashi Hasegawa

    International Workshop on High-Entropy Alloys  2023.2.14 

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    Event date: 2023.2

    Language:English   Presentation type:Symposium, workshop panel (public)  

  10. ハイエントロピー酸化物(MgCoNiCuZn)Oの低温熱膨張および圧縮挙動

    張 仲景,佐々木 拓也,GAIDA Nico Alexander,丹羽 健,長谷川 正

    第63回高圧討論会  2022.12.13 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

  11. 超高圧下におけるM(M = Fe, Ru)-C-H系化合物の合成と相安定性

    丹羽 健,中島 健太,佐々木 拓也,長谷川 正

    第63回高圧討論会  2022.12.14 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Oral presentation (general)  

  12. Cr-Ge系チムニーラダー型非整合複合結晶の相安定性と磁性および元素置換

    佐々木 拓也,野田 航希,GAIDA Nico Alexander,丹羽 健,長谷川 正

    第63回高圧討論会  2022.12.14 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Oral presentation (general)  

  13. N-Nダイマーを有する新規窒化モリブデンMo3N5の超高圧合成と結晶構造

    佐々木 拓也,山本 拓朗,浅野 秀斗,丹羽 健,長谷川 正

    第63回高圧討論会  2022.12.14 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Oral presentation (general)  

  14. 新規な六方晶Cr-Ge系化合物の高温高圧合成と磁気的性質

    武田 良樹,佐々木 拓也,鬼丸 孝博,丹羽 健,長谷川 正

    第63回高圧討論会  2023.2.13 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

  15. 新規高圧相マンガン窒化物の相安定性及び圧縮挙動

    浅野 秀斗,丹羽 健,河口 沙織,佐々木 拓也,長谷川 正

    第63回高圧討論会  2023.2.13 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

  16. 新規W-Sn系化合物の超高圧合成と電子構造

    加藤 有真,佐々木 拓也,丹羽 健,長谷川 正

    第63回高圧討論会  2022.12.13 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

  17. 5 族, 6族遷移金属ハイエントロピー窒化物単結晶の高温高圧合成

    神崎 亮,佐々木 拓也,GAIDA Nico Alexander,丹羽 健,長谷川 正

    第63回高圧討論会  2022.12.13 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

  18. クリプトンハイドレートsH相の弾性的性質とケージ占有性に関する研究

    勝俣 麻,夏目 宏一,永江 峰幸,丹羽 健,木村 友亮,坂田 雅文,佐々木 重雄

    第63回高圧討論会  2022.12.13 

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    Event date: 2022.12

    Language:Japanese   Presentation type:Poster presentation  

  19. 塩化アンモニウムを用いたハイエントロピー窒化物の高温高圧単結晶育成

    神崎 亮,佐々木 拓也,Gaida Nico Alexander,丹羽 健,長谷川正

    第32回 材料フォーラムTOKAI  2022.11.7 

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    Event date: 2022.11

    Language:Japanese   Presentation type:Oral presentation (general)  

  20. 高圧力下におけるGe 固溶ルチル型TiO2 の合成と結晶成長

    柴田 壮理,丹羽健,佐々木拓也,長谷川正

    第32回 材料フォーラムTOKAI  2022.11.7 

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    Event date: 2022.11

    Language:Japanese   Presentation type:Oral presentation (general)  

  21. 新規W-Sn 系化合物の超高圧合成と結晶構造および電子構造

    加藤 有真,佐々木拓也,丹羽健,長谷川正

    第32回 材料フォーラムTOKAI  2022.11.7 

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    Event date: 2022.11

    Language:Japanese   Presentation type:Oral presentation (general)  

  22. 超高圧下におけるKr とのファンデルワールス化合物の探索

    朝田 敢斗,丹羽健,佐々木拓也,長谷川正

    第32回 材料フォーラムTOKAI  2022.11.7 

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    Event date: 2022.11

    Language:Japanese   Presentation type:Oral presentation (general)  

  23. 高圧下における塩化アンモニウムを用いたハイエントロピー遷移金属窒化物の合成

    神崎亮,佐々木拓也,丹羽健,Gaida Nico Alexander,長谷川正

    第32回 材料フォーラムTOKAI  2022.11.7 

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    Event date: 2022.11

    Language:Japanese   Presentation type:Oral presentation (general)  

  24. 新規六方晶Cr-Ge 系化合物の高温高圧合成と磁性

    武田良樹,佐々木拓也,丹羽健,長谷川正

    第32回 材料フォーラムTOKAI  2022.11.7 

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    Event date: 2022.11

    Language:Japanese   Presentation type:Oral presentation (general)  

  25. Mn5Si3型Cr5Ge3の高圧合成と磁性

    武田 良樹,佐々木 拓也,丹羽 健,長谷川 正

    日本金属学会2022年秋期第171回講演大会  2022.9.23 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

  26. 高温高圧下におけるハイエントロピー無機材料の創製 Invited

    佐々木 拓也,丹羽 健,長谷川 正

    日本金属学会2022年秋期第171回講演大会  2022.9.22 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

  27. 有機金属錯体を用いたM(M = Fe, Ru)-C-H系化合物の超高圧合成と相安定性

    丹羽 健,中島 健太,佐々木 拓也,長谷川 正

    日本金属学会2022年秋期第171回講演大会  2022.9.23 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

  28. 超高圧力下におけるマンガン窒化物合成のその場観察と相安定性

    浅野 秀斗,丹羽 健,河口 沙織,佐々木 拓也,長谷川 正

    日本金属学会2022年秋期第171回講演大会  2022.9.21 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

  29. 新規W-Sn系化合物の超高圧合成と結晶構造

    加藤 有真,佐々木 拓也,丹羽 健,長谷川 正

    日本金属学会2022年秋期第171回講演大会  2022.9.22 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

  30. 塩化アンモニウムを用いたハイエントロピー遷移金属窒化物の高温高圧合成

    神崎 亮,佐々木 拓也,丹羽 健,Gaida Nico Alexander,長谷川正

    公益社団法人日本セラミックス協会第35回秋季シンポジウム  2022.9.14 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

  31. スピネル型ハイエントロピー酸化物蛍光体の合成と発光特性

    佐々木 拓也,丹羽 健,長谷川 正

    公益社団法人日本セラミックス協会第35回秋季シンポジウム  2022.9.15 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

  32. マンガン窒化物の超高圧合成と高圧その場観察

    浅野 秀斗,丹羽 健,佐々木 拓也,長谷川 正

    公益社団法人日本セラミックス協会第35回秋季シンポジウム  2022.9.15 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

  33. The low temperature thermal expansion behavior of entropy stabilized oxide (MgCoNiCuZn)O

    2022.9.14 

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    Event date: 2022.9

    Language:Japanese   Presentation type:Oral presentation (general)  

  34. 超高圧高温下で成長したTa-N系ナノワイヤー結晶のモルフォロジーと構造

    長谷川 正、Gaida Nico、佐々木 拓也、石川 亮、丹羽 健、山根 久典、柴田 直哉、幾原 雄一

    日本金属学会2022年春期(第170回)講演大会 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  35. Highly Coordinated Tungsten Nitride with U7Te12-type Structure Synthesized Using the Laser-Heated Diamond Anvil Cell International conference

    Chung-Ching Chang, Takuya Sasaki, Nico Alexander Gaida, Ken Niwa, Masashi Hasegawa

    APS March Meeting 2022 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:United States  

  36. 高配位遷移金属リン化物の超高圧合成と結晶化学

    丹羽 健・松尾 拓・西堂園 啓太・佐々木 拓也・GAIDA Nico Alexander・長谷川 正

    日本セラミックス協会2022年年会 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  37. 高圧下における新規 Cr–Si 系化合物の合成と相安定性

    佐々木 拓也・高野 航一・ガイダ ニコ アレクサンダー・丹羽 健・長谷川 正

    日本セラミックス協会2022年年会 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  38. U7Te12型タングステン窒化物の高圧合成および結晶構造

    張 仲景・佐々木 拓也・Gaida Nico Alexander・丹羽 健・長谷川 正

    日本セラミックス協会2022年年会 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  39. 超高圧合成した新規二窒化バナジウムの価数状態、圧縮挙動及び熱膨張挙動

    浅野 秀斗・丹羽 健・佐々木 拓也・ガイダ ニコ アレキサンダー・長谷川 正

    日本セラミックス協会2022年年会 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  40. 超高圧下における新規無機化合物の創製と物質科学 Invited

    丹羽健

    ISSPワークショップ「高圧セミナー “最近の話題から”」 

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    Event date: 2022.3

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Venue:オンライン   Country:Japan  

  41. High-pressure synthesis of highly coordinated U7Te12-type W7N12 International conference

    Chung-Ching Chang, Nico Alexander Gaida, Takuya Sasaki, Ken Niwa, Masashi Hasegawa

    International Core-to-Core Conference on Mixed Anion Research for Energy Conversion 

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    Event date: 2022.1

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  42. High-Pressure Synthesis and Thermal Expansion of Novel Transition Metal Pernitride, CuAl2-type VN2 International conference

    Shuto Asano, Ken Niwa, Takuya Sasaki, Nico Alexander Gaida, Masashi Hasegawa

    International Core-to-Core Conference on Mixed Anion Research for Energy Conversion 

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    Event date: 2022.1

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  43. マルチアンビルプレスを用いた新規 Eu 賦活 CaAl2 O4 蛍光体の高圧合成および発光特性

    立岩一晃,佐々木拓也,GAIDA Nico Alexander,丹羽健,長谷川正

    第10回名古屋大学シンクロトロン光研究センターシンポジウム 

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    Event date: 2022.1

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  44. 前駆体を用いた 8 族遷移金属炭化物の超高温高圧合成

    中島健太,丹羽健,佐々木拓也,GAIDA Nico Alexander,長谷川正

    第10回名古屋大学シンクロトロン光研究センターシンポジウム 

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    Event date: 2022.1

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  45. Cr-Ge 系 Chimney-Ladder 化合物の高温高圧合成および磁気的性質

    野田航希,佐々木拓也,ガイダ ニコ アレクサンダー,丹羽健,長谷川

    第10回名古屋大学シンクロトロン光研究センターシンポジウム 

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    Event date: 2022.1

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  46. 新規なバナジウム二窒化物の高圧合成と熱膨張挙動

    浅野 秀斗 ・ 丹羽 健 ・ 佐々木 拓也 ・ GAIDA Nico Alexander ・ 長谷 川 正

    第10回名古屋大学シンクロトロン光研究センターシンポジウム 

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    Event date: 2022.1

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  47. 超高圧下における新物質合成と放射光X線構造解析

    佐々木 拓也 , 丹羽 健, 長谷川 正

    第10回名古屋大学シンクロトロン光研究センターシンポジウム 

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    Event date: 2022.1

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  48. 高配位数のW-N多面体を持つU7Te12型WNの高圧合成

    張 仲景, 佐々木 拓也, Gaida Nico Alexander, 丹羽 健, 長谷川 正

    第10回名古屋大学シンクロトロン光研究センターシンポジウム 

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    Event date: 2022.1

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  49. ギガパスカル以上の超高圧力領域での新物質結晶成⻑ Invited

    ⻑谷川正,丹羽健,佐々木拓 也,Gaida Nico Alexander,石川 亮,山根久典,柴田直哉,幾原 雄一

    日本結晶成長学会第50回結晶成長国内会議 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Venue:姫路   Country:Japan  

  50. メタンハイドレート sH 相におけるメタン分子の 51268 ケージ占有数に 関する考察

    角谷 一樹 ・ 久保田 雅人 ・ 永江 峰幸 ・ 丹羽 健 ・ 木村 友亮 ・ 坂田 雅文 ・ 佐々木 重雄

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  51. High-pressure synthesis of U7Te 12-type W7N12 with high coordination W-N polyhedra

    張 仲景 ・ 佐々木 拓也 ・ GAIDA Nico Alexander ・ 丹羽 健 ・ 長谷川 正

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  52. 前駆体を用いた 8 族遷移金属炭化物の超高温高圧合成

    中島 健太 ・ 丹羽 健 ・ 佐々木 拓也 ・ GAIDA Nico Alexander ・ 長谷川 正

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  53. Cr-Ge 系 Chimney-Ladder 化合物の高温高圧合成および磁気的性 質

    野田 航希 ・ 佐々木 拓也 ・ GAIDA Nico Alexander ・ 丹羽 健 ・ 長谷川 正

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  54. 新規なバナジウム二窒化物の高圧合成と熱膨張挙動

    浅野 秀斗 ・ 丹羽 健 ・ 佐々木 拓也 ・ GAIDA Nico Alexander ・ 長谷 川 正

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  55. マルチアンビルプレスを用いた新規 Eu 賦活 CaAl2O4 蛍光体の 高圧合成および発光特性

    立岩 一晃 ・ 佐々木 拓也 ・ GAIDA Nico Alexander ・ 丹羽 健 ・ 長谷川 正

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  56. 超高圧高温下で成長した Ta-N 系ナノワイヤー結晶のモルフォロ ジーと構造

    長谷川 正 ・ GAIDA Nico Alexander・佐々木 拓也・石川 亮・丹羽 健・山根 久典・柴田 直哉・ 幾原 雄一

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  57. 新規Cr-Si系化合物の高圧合成と結晶構造

    佐々木 拓也,高野 航一,GAIDA Nico Alexander,丹羽 健,長谷川 正

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  58. 超高圧下における多結晶 PtN2 膜の合成と特性評価

    丹羽 健 ・ 飯塚 友規 ・ 黒澤 昌志 ・ 中村 優斗 ・ 岸田 英夫 ・ 中塚 理 ・ 佐々木 拓也 ・ GAIDA Nico Alexander ・ 長谷川 正

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  59. 硫化水素ハイドレートの圧力誘起相変化

    久保田 雅人 ・ 角谷 一樹 ・ 永江 峰幸 ・ 丹羽 健 ・ 木村 友亮 ・ 坂田 雅文 ・ 佐々木 重雄

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  60. 超高圧高温下で成長した Ta-N 系ナノワイヤー結晶のモルフォロ ジーと構造

    長谷川 正 ・ GAIDA Nico Alexander・佐々木 拓也・石川 亮・丹羽 健・山根 久典・柴田 直哉・ 幾原 雄一

    第62回高圧討論会 

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    Event date: 2021.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:姫路   Country:Japan  

  61. ダイアモンドアンビルセルを用いたU7Te12型高配位新規窒化タングステンの合成

    張 仲景、Gaida Nico Alexander、佐々木 拓也、丹羽 健、長谷川 正

    日本金属学会2021年秋期(第169回)講演大会 

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    Event date: 2021.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  62. 超高圧合成による新規バナジウム二窒化物の合成と圧縮及び熱膨張挙動

    浅野 秀斗、丹羽 健、佐々木 拓也、Gaida Nico Alexander、長谷川 正

    日本金属学会2021年秋期(第169回)講演大会 

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    Event date: 2021.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  63. 超高圧下で単結晶サファイア基板上に成長したPtN2膜の性状と物性

    丹羽 健、飯塚 友規、黒澤 昌志、中村 優斗、岸田 英夫、中塚 理、佐々木 拓也、Gaida Nico Alexander、長谷川 正

    日本金属学会2021年秋期(第169回)講演大会 

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    Event date: 2021.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  64. Cr-Ge系 Chimney-Ladder化合物の組成および磁気的性質の圧力依存性

    野田 航希、佐々木 拓也、ニコ アレクサンダー ガイダ、丹羽 健、長谷川 正

    日本金属学会2021年秋期(第169回)講演大会 

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    Event date: 2021.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  65. アンモニウム塩を用いた多成分系5・6族遷移金属窒化物の高圧合成

    佐々木 拓也・神崎 亮・GAIDA Nico Alexander・丹羽 健・長谷川 正

    日本セラミックス協会第34回秋季シンポジウム  

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    Event date: 2021.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  66. High-pressure synthesis of tungsten nitride by nitridation with ammonium chloride Invited International conference

    Takuya Sasaki, Takahide Ikoma, Kazuki Sago, Ken Niwa, Masashi Hasegawa

    THERMEC'2021  

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    Event date: 2021.6

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Austria  

  67. In situ synchrotron diffraction and sound velocity measurements of transparent nanoceramics consisting of low-symmetry crystals Invited International conference

    Nico Alexander Gaida, Steeve Gréaux, Yoshio Kono, Hideharu Kuwahara, Norimasa Nishiyama, Oliver Beermann, Ken Niwa, Masashi Hasegawa

    THERMEC'2021  

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    Event date: 2021.6

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Austria  

  68. High Pressure Synthesis, Compression Behaviours, Crystal Chemistry and Electronic States of Novel Metal Nitrides Invited International conference

    Shuto Asano,Masashi Hasegawa, Ken Niwa, Takuya Sasaki, Nico Alexander Gaida, Zheng Liu, Kazuo Soda, Tetsu Ohsuna

    THERMEC'2021  

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    Event date: 2021.6

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Austria  

  69. ダイヤモンドアンビルセルを用いた新物質合成と物質科学

    丹羽 健

    日本高圧力学会主催 未来を拓く高圧力科学技術セミナーシリーズ(45) 

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    Event date: 2021.3

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Venue:オンライン   Country:Japan  

  70. 超高圧下における新規遷移金属リン化物の合成と結晶構造および相安定性

    丹羽 健, 松尾 拓, 西堂園 啓太, 佐々木 拓也, GAIDA Nico Alexander, 長谷川 正

    第61回高圧討論会 

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    Event date: 2020.12

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  71. 新規ニオブ窒化物 Nb2N3 の超高圧合成と結晶構造および物性

    浅野 秀斗, 丹羽 健, 佐々木 拓也, GAIDA Nico Alexander, 長谷川 正

    第65回高圧討論会 

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    Event date: 2020.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  72. Synthesis of Novel Tungsten Nitrides under High-pressure and High-temperature using Diamond Anvil Cell

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    Event date: 2020.12

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  73. 新規 Cr-Ge 系金属間化合物の超高圧合成と結晶構造,弾性特性 および電子構造

    蟹江 宏太, 佐々木 拓也, 横井 達矢, 丹羽 健, GAIDA Nico Alexander, 松永 克志, 長谷川 正

    第63回高圧討論会 

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    Event date: 2020.12

    Language:Japanese   Presentation type:Poster presentation  

    Venue:オンライン   Country:Japan  

  74. Phase relations in magnesium silicides at high pressure and temperature from synchrotron diffraction techniques

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    Event date: 2020.12

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  75. 塩化アンモニウムを用いた窒化ニオブの高圧力合成と結晶化学

    佐々木 拓也, 生駒 鷹秀, GAIDA Nico Alexander, 丹羽 健, 長谷川 正

    第62回高圧討論会 

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    Event date: 2020.12

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  76. Growth of nanowire crystals of tantalum nitride in ammonium halides at high pressures

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    Event date: 2020.11

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  77. 新規Cr-Ge系金属間化合物の超高圧合成

    蟹江宏太, 佐々木拓也, 横井達矢, 丹羽健, GAIDA Nico Alexander, 松永克志, 長谷川正

    日本金属学会2020年秋期講演(第168回)大会 

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    Event date: 2020.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  78. ダイアモンドアンビルセルを用いた高温高圧下における新規窒化タングステンの合成

    張仲景, 佐々木拓也, 丹羽健, ガイダニコ アレクサンダー, 長谷川正

    日本金属学会2020年秋期講演(第168回)大会 

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    Event date: 2020.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  79. 超高圧力下における新規窒化タングステンの合成

    張 仲景,佐々木 拓也,丹羽 健,Nico Alexander Gaida,長谷川 正

    日本セラミックス協会 2020年年会 

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    Event date: 2020.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:明治大学 駿河台キャンパス   Country:Japan  

  80. 新規Cr-Ge系金属間化合物CrGe2の超高圧合成と結晶構造および弾性特性

    蟹江 宏太、丹羽 健、佐々木 拓也、Gaida Nico Alexander、長谷川 正

    日本セラミックス協会 2020年年会 

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    Event date: 2020.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:明治大学(駿河台キャンパス)  (東京都千代田区神田駿河台 1-1)   Country:Japan  

  81. アンモニウム塩を窒素源とした窒化ニオブの超高圧力合成と結晶化学

    佐々木 拓也,生駒 鷹秀,GAIDA Nico Alexander,丹羽 健,長谷川 正

    日本セラミックス協会 2020年年会 

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    Event date: 2020.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:工学院大学(新宿キャンパス)   Country:Japan  

  82. X線分光と光電子分光による遷移金属多窒化物の電子構造の評価

    曽田一雄, 加藤政彦, 丹羽健, 長谷川正

    日本金属学会2020年春期講演大会 

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    Event date: 2020.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京工業大学 大岡山キャンパス(東京都目黒区)   Country:Japan  

  83. 高圧合成NbP2の顕微分光

    川田拓也,曽田一雄,加藤政彦,西堂園啓太,丹羽健,長谷川正,池本夕佳

    第33回日本放射光学会年会・放射光科学合同シンポジウム 

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    Event date: 2020.1

    Language:Japanese   Presentation type:Poster presentation  

    Venue:ウインクあいち(名古屋市)   Country:Japan  

  84. M添加BaTaO2NのNおよびO K吸収端軟X線分光

    茨木俊貴,加藤政彦,曽田一雄,Kojamberdiev Mirabbos,丹羽健,長谷川正,高倉将一,仲武昌史

    第33回日本放射光学会年会・放射光科学合同シンポジウム 

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    Event date: 2020.1

    Language:Japanese   Presentation type:Poster presentation  

    Venue:ウインクあいち(名古屋市)   Country:Japan  

  85. High Pressure Synthesis and Compression Behavior of Hexagonal CrN2 International conference

    Ken NIWA, Takuro Yamamoto, Takuya Sasaki and Masashi Hasegawa

    Materials Research Meeting 2019 

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    Event date: 2019.12

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  86. Mechanical properties of transparent birefringent aluminosilicate nanoceramics International conference

    Nico Alexander GAIDA, Norimasa NISHIYAMA , Oliver BEERMANN, Atsunobu MASUNO, Ulrich SCHÜRMANN, Christopher GIEHL, Ken NIWA, Masashi HASEGAWA, Shrikant BHAT, Robert FARLA, Lorenz KIENLE

    MRM2019 

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    Event date: 2019.12

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  87. High-pressure synthesis and crystal structure of MoC-type WNx International conference

    Takuya Sasaki, Takahide Ikoma, Kazuki Sago, Zheng Liu, Ken Niwa, Tetsu Ohsuna, Masashi Hasegawa

    MATERIALS RESEARCH MEETING 2019 (MRM2019) 

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    Event date: 2019.12

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  88. 塩化アンモニウムを用いた遷移金属窒化物の高圧高温単結晶育成

    生駒鷹秀,GAIDA Nico Alexander,佐々木拓也,丹羽健,長谷川正

    第48回結晶成長国内会議 

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    Event date: 2019.10 - 2019.11

    Language:Japanese   Presentation type:Poster presentation  

    Venue:大阪大学(銀杏会館)   Country:Japan  

  89. Growth of tantalum oxynitride nanowires under high pressure and temperature International conference

    GAIDA Nico Alexander, SASAKI Takuya, LIU Zheng, NIWA Ken, HIROZAWA Masaki, OHSUNA Tetsu, HASEGAWA Masashi

    PACRIM13 

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    Event date: 2019.10 - 2019.11

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  90. Synthesis, crystal structure, and photoluminescence properties of Ce-doped garnet-type Ca2(Y,Gd)Sn2Al3O12 International conference

    Takuya Sasaki, Takayoshi Iwai, Ken Niwa, Masashi Hasegawa

    The 13th Pacific Rim Conference of Ceramic Societies (PACRIM13) 

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    Event date: 2019.10

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  91. 白金二窒化物薄膜の超高圧合成と物性

    飯塚 友規,丹羽 健,佐々木 拓也,長谷川 正

    第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:かでる2・7 北海道立道民活動センター   Country:Japan  

  92. 高温高圧合成手法を用いた新規IV族元素充填スクッテルダイト化合物の探査

    市川将成,丹羽 健,佐々木 拓也,長谷川 正

    第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:かでる2・7 北海道立道民活動センター(札幌市中央区)   Country:Japan  

  93. 新規窒化クロムの超高圧合成と結晶構造および圧縮挙動

    丹羽 健,山本拓朗,佐々木拓也,長谷川正

    第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:かでる2・7 北海道立道民活動センター(札幌市中央区)   Country:Japan  

  94. モリブデン二燐化物の超高圧高温相安定性と新規高圧生成相の評価

    松尾 拓,丹羽 健,佐々木 拓也,長谷川 正

    第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:かでる2・7 北海道立道民活動センター(札幌市中央区)   Country:Japan  

  95. LH-DACを用いた高圧高温超臨界水中での金属のレーザー加熱と水素化物の形成

    長谷川 正,曽田一雄,丹羽 健,大塚春男,杉浦慎哉,山口貫太,佐々木拓也,加藤政彦, 鈴木耕拓,石神龍哉

    日本高圧力学会第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:かでる2・7 北海道立道民活動センター(札幌市中央区)   Country:Japan  

  96. ビスマス窒化物の超高圧合成と結晶構造および相安定性

    野村 俊介,丹羽 健,佐々木 拓也,長谷川 正

    第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:かでる2・7 北海道立道民活動センター   Country:Japan  

  97. 塩化アンモニウムを窒素源とした窒化タングステンの高圧合成と結晶化学

    佐々⽊ 拓也,⽣駒 鷹秀,佐合 ⼀樹,劉 崢,丹⽻ 健,⼤砂 哲,⻑⾕川 正

    第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:かでる2・7 北海道立道民活動センター(札幌市中央区)   Country:Japan  

  98. High-pressure growth of tantalum oxynitride nanowires

    Gaida Nico Alexander, Sasaki Takuya, Liu Zheng, Niwa Ken, Hirozawa Masaki, Ohsuna Tetsu, Hasegawa Masashi

    第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:かでる2・7 北海道立道民活動センター(札幌市中央区)   Country:Japan  

  99. 塩化アンモニウムを用いた3d・4d遷移金属窒化物の高圧高温結晶成長

    生駒鷹秀,佐々木拓也,丹羽健,長谷川正

    第60回高圧討論会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:かでる2・7 北海道立道民活動センター(札幌市中央区)   Country:Japan  

  100. 白金二窒化物薄膜の超高圧合成と膜性状

    飯塚 友規,丹羽 健,佐々木 拓也,長谷川 正

    第29回学生による材料フォーラム 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  101. Effect of lanthanide ion (Gd3+) or Y3+ doping on the color performance of NaCeMo2O8 yellow pigment

    Yanfei Cai, Takuya Sasaki, Ken Niwa, Masashi Hasegawa

    学生による材料フォーラム&日本金属学会 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  102. ビスマス窒化物の超高圧合成と結晶構造および相安定性

    野村 俊介,丹羽 健,佐々木 拓也,長谷川 正

    第29回学生による材料フォーラム 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  103. 塩化アンモニウムを用いた層状ニオブ窒化物の高温高圧単結晶育成

    生駒鷹秀,佐々木拓也,丹羽健,長谷川正

    第29回学生による材料フォーラム 

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  104. Mn賦活ガーネット型構造赤色蛍光体の合成および発光特性

    安積 良太, 佐々木 拓也, 丹羽 健, 長谷川 正

    第29回 学生による材料フォーラム  

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    Event date: 2019.10

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  105. 新規ニッケル二窒化物の超高圧高温合成および相安定性

    福井陸,丹羽健,佐々木拓也,長谷川正

    新学術領域研究「機能コアの材料科学」 第1回若手の会 

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    Event date: 2019.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:静岡県浜松市北区三ヶ日町下尾奈 2251   Country:Japan  

  106. 新規Cr-Ge系金属間化合物の超高圧合成と結晶構造

    蟹江 宏太、丹羽 健、佐々木 拓也、長谷川 正

    新学術領域研究「機能コアの材料科学」第一回若手の会 

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    Event date: 2019.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:静岡県浜松市北区三ヶ日町下尾奈 2251   Country:Japan  

  107. 新規アルミン酸塩(Ba,Sr)2Al6O11:Eu蛍光体の高圧合成と発光特性

    佐々木 拓也,丹羽 健,長谷川 正

    新学術領域研究「機能コアの材料科学」第1回若手の会 

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    Event date: 2019.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:静岡県浜松市北区三ヶ日町下尾奈 2251   Country:Japan  

  108. 新規CrN2の超高圧合成と単結合窒素配列による異方的軸圧縮挙動

    丹羽 健,山本拓朗,佐々木拓也,長谷川正

    日本金属学会 2019年秋期(第165回)講演大会 

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    Event date: 2019.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:岡山大学(津島キャンパス)   Country:Japan  

  109. High-pressure growth of tantalum oxynitride nanowires

    Gaida Nico Alexander, Sasaki Takuya, Liu Zheng, Niwa Ken, Hirozawa Masaki, Ohsuna Tetsu, Hasegawa Masashi

    日本金属学会2019年秋期講演大会 

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    Event date: 2019.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:岡山大学(津島キャンパス)   Country:Japan  

  110. Eu賦活新規アルミン酸塩(Sr,Ba)2Al6O11蛍光体の高圧合成,結晶構造および発光特性

    佐々木 拓也,丹羽 健,長谷川 正

    日本金属学会 2019年秋期(第165回)講演大会 

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    Event date: 2019.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:岡山大学(津島キャンパス)   Country:Japan  

  111. 白金二窒化物薄膜の超高圧合成と膜性状

    飯塚 友規,丹羽 健,佐々木 拓也,長谷川 正

    東京大学物性研究所短期研究会 高圧合成による新規材料開発と高圧下測定技術の集結 

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    Event date: 2019.7

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京大学 物性研究所   Country:Japan  

  112. 新規充填スクッテルダイト化合物ZrCo4Sb12の高温高圧合成

    市川将成,佐々木 拓也,丹羽 健,長谷川 正

    高圧合成による新規材料開発と高圧下測定技術の集結(東京大学物性研究所短期研究会) 

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    Event date: 2019.7

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京大学 物性研究所   Country:Japan  

  113. レーザー加熱式ダイアモンドアンビルセルを用いた新規遷移金属窒化物の超高圧合成と結晶化学

    丹羽 健,曽田 一雄,佐々木 拓也,長谷川 正

    高圧合成による新規材料開発と高圧下測定技術の集結(東京大学物性研究所短期研究会) 

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    Event date: 2019.7

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Venue:東京大学物性研究所柏キャンパス(本館6階 大講義室(A632))   Country:Japan  

  114. モリブデン燐化物の超高圧相安定性と新規相の生成

    松尾 拓,丹羽 健,佐々木 拓也,長谷川 正

    高圧合成による新規材料開発と高圧下測定技術の集結(東京大学物性研究所短期研究会) 

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    Event date: 2019.7

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京大学 物性研究所   Country:Japan  

  115. Growth of tantalum oxynitride nanowires under high pressure

    Gaida Nico Alexander, Sasaki Takuya, Liu Zheng, Niwa Ken, Hirozawa Masaki, Ohsuna Tetsu, Hasegawa Masashi

    短期研究会「高圧合成による新規材料開発と高圧下測定技術の集結」 

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    Event date: 2019.7

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京大学物性研究所   Country:Japan  

  116. マルチアンビルプレスを用いた窒化タングステンの高圧合成と結晶構造

    佐々⽊ 拓也,⽣駒 鷹秀,佐合 ⼀樹,劉 崢,丹⽻ 健,⼤砂 哲,⻑⾕川 正

    東京大学物性研究所短期研究会 高圧合成による新規材料開発と高圧下測定技術の集結 

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    Event date: 2019.7

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京大学 物性研究所   Country:Japan  

  117. 塩化アンモニウムを用いた層状ニオブ窒化物の高温高圧単結晶育成

    生駒鷹秀,佐々木拓也,丹羽健,長谷川正

    東京大学物性研究所短期研究会「高圧合成による新規材料開発と高圧下測定技術の集結」 

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    Event date: 2019.7

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京大学 物性研究所   Country:Japan  

  118. 白金二窒化物薄膜の超高圧合成と膜性状

    飯塚 友規,丹羽 健,佐々木 拓也,長谷川 正

    第4回固体化学フォーラム 

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    Event date: 2019.6

    Language:Japanese   Presentation type:Poster presentation  

    Venue:岡崎コンファレンスセンター   Country:Japan  

  119. 新規充填スクッテルダイト化合物ZrCo4Sb12の高温高圧合成

    市川将成,佐々木 拓也,丹羽 健,長谷川 正

    第4回固体化学フォーラム研究会 

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    Event date: 2019.6

    Language:Japanese   Presentation type:Poster presentation  

    Venue:岡崎コンファレンスセンター   Country:Japan  

  120. モリブデン燐化物の超高圧相安定性と新規相の生成

    松尾 拓,丹羽 健,佐々木 拓也,長谷川 正

    第4回固体化学フォーラム研究会 

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    Event date: 2019.6

    Language:Japanese   Presentation type:Poster presentation  

    Venue:岡崎コンファレンスセンター   Country:Japan  

  121. 新規アルミン酸塩Ba2Al6O11:Eu蛍光体の高圧合成と発光特性

    佐々木 拓也,丹羽 健,長谷川 正

    第4回固体化学フォーラム 

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    Event date: 2019.6

    Language:Japanese   Presentation type:Poster presentation  

    Venue:岡崎コンファレンスセンター   Country:Japan  

  122. 塩化アンモニウムを用いた層状ニオブ窒化物の高温高圧単結晶育成

    生駒鷹秀,佐々木拓也,丹羽健,長谷川正

    第4回固体化学フォーラム研究会 

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    Event date: 2019.6

    Language:Japanese   Presentation type:Poster presentation  

    Venue:岡崎コンファレンスセンター   Country:Japan  

  123. High-Pressure Synthetic Approach to Novel Binary Nitrides International conference

    Ken NIWA, Kentaro Suzuki, Toshiki Terabe, Takuro Yamamoto, Hirokazu Ogasawara, Shin Takayama, Tomoya Inagaki, Takuya Sasaki and Masashi Hasegawa

    10th International Symposium on Nitrides (ISNT2019) 

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    Event date: 2019.6

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Spain  

  124. 放射光と超高圧力場が切り拓く新物質創製

    丹羽 健

    シンクロトロン光利用者研究会:放射光入門 「材料研究の現場で活用される放射光分析技術」 

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    Event date: 2019.4

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Venue:愛知県産業労働センター「ウインクあいち」 15階 交流センター   Country:Japan  

  125. 新規充填スクッテルダイト化合物ZrCo4Sb12の高温高圧合成

    市川将成,佐々木 拓也,丹羽 健,長谷川 正

    日本セラミックス協会 2019年年会 

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    Event date: 2019.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:工学院大学(新宿キャンパス)   Country:Japan  

  126. 塩化アンモニウムを用いた層状ニオブ窒化物の高温高圧単結晶育成

    生駒鷹秀,佐々木拓也,丹羽健,川田拓也,曽田一雄,長谷川正

    日本セラミックス協会2019年年会 

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    Event date: 2019.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:工学院大学(新宿キャンパス)   Country:Japan  

  127. 遷移金属多窒化物TN2のN 1s軟X線吸収スペクトル

    曽田一雄,前口景祐,川田拓也,茨木俊貴,加藤政彦,丹羽 健,長谷川 正,高倉将一,仲武昌史

    日本物理学会第74回年次大会 

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    Event date: 2019.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:九州大学伊都キャンパス(福岡県福岡市)   Country:Japan  

  128. 超高圧下で合成された新規二元系窒化物の結晶化学と圧縮特性

    丹羽 健,長谷川 正

    東北大学金属材料研究所 共同利用ワークショップ 放射光物質構造科学の新展開:高圧物質科学と地球惑星科学 

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    Event date: 2018.12

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Country:Japan  

  129. 超高圧下で合成された新規レニウム多窒化物の結晶構造と相安定性

    丹羽 健,高山 新,劉 崢,大砂 哲,佐々木 拓也,長谷川 正

    第59回高圧討論会 

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    Event date: 2018.11

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  130. 新規な高配位ニオブリン化物の超高圧合成と構造相転移

    丹羽 健,西堂園 啓太,佐々木 拓也,長谷川 正

    公益社団法人 日本金属学会 2018年周期講演(第163回)大会 

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    Event date: 2018.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  131. Ultra-high pressure synthesis of main group element nitrides Invited International conference

    Ken NIWA

    9th International Workshop on Spinel Nitrides and Related Materials 

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    Event date: 2018.9

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Germany  

  132. High pressure synthesis and characterization of new group-14 (elements) pernitrides International conference

    Ken NIWA, Hirokazu OGASAWARA, Tomoya INAGAKI, Masashi HASEGAWA

    Thermec 2018 

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    Event date: 2018.7

    Language:English   Presentation type:Oral presentation (general)  

    Country:France  

  133. 超高圧力下における新規多窒化物の合成と結晶化学

    丹羽 健

    第3回固体化学フォーラム研究会 

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    Event date: 2018.6

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Country:Japan  

  134. Ultra-high Pressure Synthesis of New Nitrides International conference

    Ken NIWA, Masashi HASEGAWA

    14th International Ceramics Congress 

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    Event date: 2018.6

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Italy  

  135. High pressure crystal chemistry and compression behaviors of novel early transition-metal nitrides International conference

    Ken NIWA, Masashi HASEGAWA, Takuro YAMAMOTO, Kazuo SODA

    APS March Meeting 2018 

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    Event date: 2018.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:United States  

  136. New group-14 element pernitrides synthesized at high pressure and temperature International conference

    Ken NIWA, Hirokazu OGASAWARA, Tomoya INAGAKI, Masashi HASEGAWA

    APS March Meeting 2018 

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    Event date: 2018.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  137. あいちシンクロトロン光を利用した超高圧下における回折実験と新規無機物質の探査

    丹羽 健・松崎 郁弥・寺部 俊紀・小笠原 宏和・西堂園 啓太・山本 拓朗・長谷川 正

    第7回名古屋大学シンクロトロン光研究センターシンポジウム 

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    Event date: 2018.1

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  138. 高圧下における新規ニオブリン化物の合成と構造安定性 International conference

    丹羽 健・西堂園 啓太・長谷川 正

    第58回高圧討論会 

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    Event date: 2017.11

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  139. 新規ニオブリン化物の高圧合成と結晶構造および安定性

    丹羽 健・西堂園 啓太・長谷川 正

    公益社団法人日本セラミックス協会第30回秋季シンポジウム 

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    Event date: 2017.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  140. High Pressure Synthesis of Pyrite-type Group-14 Nitrides International conference

    Ken NIWA

    9th Iternational Symposium on Nitrides (ISNT2017) and 5th International Symposium on SiAlONs and Non-oxides (ISSNOX5) 

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    Event date: 2017.8 - 2017.9

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  141. Novel group-14 element nitrides synthesized at high pressure International conference

    Ken NIWA, Hirokazu OGASAWARA, Masashi HASEGAWA

    26th The International Conference on High Pressure Science and Technology (AIRAPT) 

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    Event date: 2017.8

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  142. High Pressure Synthesis and Characterization of Binary and Ternary Transition Metal Nitrides, International conference

    Masashi HASEGAWA, Ken NIWA

    Frontiers in Materials Processing Applications, Research and Technology 

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    Event date: 2017.7

    Language:English   Presentation type:Oral presentation (general)  

    Country:France  

  143. 新規パイライト型14族元素窒化物の超高圧合成

    丹羽 健・小笠原宏和・長谷川正

    日本セラミックス協会2017年年会 

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    Event date: 2017.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  144. 超高圧下で合成される新規窒化物 Invited

    丹羽 健

    Workshop on Materials science under ultra-high pressure MATSUYAMA 2017 

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    Event date: 2017.3

    Language:English   Presentation type:Oral presentation (general)  

    Country:Japan  

  145. 規Xe-N2系化合物の高圧合成と結晶構造および構造相転移

    丹羽 健・松崎 郁弥・白子 雄一・長谷川 正

    第57回高圧討論会 

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    Event date: 2016.10

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  146. High pressure synthesis of 3d transition metal nitrides in a laser heated diamond anvil cell Invited International conference

    Ken NIWA

    8th International Workshop Spinel Nitrides and Related Materials 

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    Event date: 2016.9

    Language:English   Presentation type:Oral presentation (general)  

    Country:Germany  

  147. Carbon polymorphic nanocrystals grown in ~GPa range high pressures using laser-heated diamond anvil cell International conference

    K. Niwa, T. Oda, M. Iida, K. Kusaba, Y. Shirako, M. Hasegawa

    The 18th International Conference on Crystal Growth and Epitaxy 

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    Event date: 2016.8

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  148. High pressure synthesis of new transition metal nitrides with using laser-heated diamond anvil cell International conference

    Ken Niwa, Toshiki Terabe, Yuichi Shirako, Shunsuke Muto, Kazuyoshi Tatsumi, Tatsuya Mizui, Kazuo Soda, Masashi Hasegawa

    International Conference on PROCESSING & MANUFACTURING OF ADVANCED MATERIALS Processing, Fabrication, Properties, Applications(THERMEC2016) 

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    Event date: 2016.5 - 2016.6

    Language:English   Presentation type:Oral presentation (general)  

    Country:Austria  

  149. 高圧下における新規3d遷移金属窒化物の合成と評価

    17. 丹羽 健,寺部 俊紀,水井 達也,加藤 大貴,白子 雄一,曽田 一雄,長谷川 正,亀卦川 卓美

    日本セラミックス協会2016年年会 

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    Event date: 2016.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  150. 超高圧直接窒化反応による窒化リンの合成と圧縮挙動

    丹羽 健,飯島 安紀,白子 雄一,浮田 昌也,豊浦 和明,松永 克志,長谷川 正

    第56回高圧討論会 

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    Event date: 2015.11

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:JMSアステールプラザ(広島市中区)   Country:Japan  

  151. 高密度結晶相により構成されたナノ多孔質構造シリカの合成と光学特性

    丹羽 健,佐々木 厳太,米田 智士,宇佐美 久尚,山中 茂,白子 雄一,長谷川 正

    日本セラミックス協会第28回秋季シンポジウム 

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    Event date: 2015.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:富山大学(五福キャンパス)   Country:Japan  

  152. High Pressure Synthesis and Characterization of Transition Metal Nitrides International conference

    Ken Niwa, Kentaro Suzuki, Toshiki Terabe, Yuichi Shirako, Shunsuke Muto, Kazuyoshi Tatsumi, Tatsuya Mizui, Kazuo Soda, Takumi Kikegawa, Masashi Hasegawa

    Joint AIRAPT-25th & EHPRG-53rd International Conference on High Pressure Science and Technology 

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    Event date: 2015.8 - 2015.9

    Language:English   Presentation type:Oral presentation (general)  

    Country:Spain  

  153. Syntheses and A-site Order-disorder Transition in (A0.25Mn0.75)(B0.25Ti0.75)O3 Perovskites International conference

    Gen Shimura, Yuichi Shirako, Ken Niwa, Masashi Hasegawa

    Joint AIRAPT-25th & EHPRG-53rd International Conference on High Pressure Science and Technology 

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    Event date: 2015.8 - 2015.9

    Language:English   Presentation type:Poster presentation  

    Country:Japan  

  154. High Pressure Chemical Reactions for Carbon Polymorphic Crystals International conference

    Joint AIRAPT-25th & EHPRG-53rd International Conference on High Pressure Science and Technology 

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    Event date: 2015.8 - 2015.9

    Language:English   Presentation type:Oral presentation (general)  

    Country:Spain  

  155. 白金族多窒化物の高圧合成と化学結合の評価

    丹羽 健,鈴木 健太郎,寺部 俊紀,武藤 俊介,巽 一厳,水井 達也,曽田 一雄,亀掛川 卓美,長谷川 正

    日本セラミックス協会2015年年会 

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    Event date: 2015.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:岡山大学(津島キャンパス)   Country:Japan  

  156. 白金族窒化物の高圧合成と評価

    丹羽 健,鈴木 健太郎,寺部 俊紀,武藤 俊介,巽 一厳,水井 達也,曽田 一雄,亀卦川 卓美,長谷川 正

    第55回高圧討論会 

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    Event date: 2014.11

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:徳島大学(常三島キャンパス)   Country:Japan  

  157. 高圧高温合成法による新規バナジウム族窒化物の探査

    丹羽 健,奥野 賢太郎,長谷川 正

    日本セラミックス協会第27回秋季シンポジウム 

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    Event date: 2014.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:鹿児島大学(郡元キャンパス)   Country:Japan  

  158. Recent Discovery of Late transition Metal (Per)Nitrides and Their Chemical Bonding International conference

    Ken NIWA, Kentaro SUZUKI, Shunsuke MUTO, Kazuyoshi TATSUMI, Kazuo SODA, Masashi HASEGAWA

    ISNT 2014: 8th International Symposium on Nitrides in Conjunction with the 7th International Workshop on Spinel Nitrides and Related Materials and the Marie Curie ITN 7th Framework Programme FUNEA 

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    Event date: 2014.8 - 2014.9

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Germany  

  159. Nano-carbon polymorphic crystals via reduction of carbon dioxide under high pressures International conference

    Ken Niwa, Masahiko Iida, Takashi Oda, Keiji Kusaba, Masashi Hasegawa

    The 6th Asian Conference on Crystal Growth and Crystal Technology 

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    Event date: 2014.6

    Language:English   Presentation type:Oral presentation (general)  

    Country:Korea, Republic of  

  160. Marcasite型白金族多窒化物の高圧高温合成と評価

    丹羽健,鈴木健太郎,武藤俊介,巽一厳,長谷川正

    日本セラミックス協会2014年年会 

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    Event date: 2014.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  161. レーザー加熱式ダイアモンドアンビルセルを用いた新規ロジウム窒化物の合成と評価

    丹羽健,鈴木健太郎,長谷川正,EREMETS Mikhail,DZIVENKO Dmytro,RIEDEL Ralf

    第54回高圧討論会 

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    Event date: 2013.11

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  162. ラマン散乱測定によるMarcasite型ロジウム窒化物中の窒素結合状態の評価

    丹羽健,鈴木健太郎,長谷川正,Mikhail Eremets,Dmytro Dzivenko,Ralf Riedel

    日本セラミックス協会第26 回秋季シンポジウム 

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    Event date: 2013.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  163. 超高圧高温下での有機無機変換によるナノ構造C-N 系化合物の合成と評価及び分析

    丹羽健,堀部太嗣,神有輝,草場啓治,安田啓介,石神龍哉,長谷川正

    日本セラミックス協会第26 回秋季シンポジウム 

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    Event date: 2013.9

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  164. Growth of rectangular hollow tube single crystals with rutile-type structure in supercritical fluids International conference

    Ken Niwa, Tomoharu Tokunaga, Masashi Hasegawa

    2013 APSSCCM/AIRAPT JOINT CONFERENCE 

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    Event date: 2013.7

    Language:English   Presentation type:Oral presentation (general)  

    Country:United States  

  165. High-pressure synthesis of BiFeO3-BiAlO3 and BiFeO3-MnTiO3 solid solutions

    Gen Shimura, Keiji Kusaba, Tetsuya Miyawaki, Ken Niwa, Hidefumi Asano, Masashi Hasegawa

    2013 APSSCCM/AIRAPT JOINT CONFERENCE 

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    Event date: 2013.7

    Language:English   Presentation type:Poster presentation  

    Country:United States  

  166. Molecular Routes Syntheses of Nano-structured C and C-N Compounds in High Pressure and Temperature using LH-DAC International conference

    Ken Niwa, Masashi Hasegawa, Taishi Horibe, Yuki Jin, Keiji Kusaba, Keisuke Yasuda , Ryoya Ishigami

    2013 APSSCCM/AIRAPT JOINT CONFERENCE 

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    Event date: 2013.7

    Language:English   Presentation type:Oral presentation (general)  

    Country:United States  

  167. 超高圧下直接窒化法によるMarcasite型ロジウム窒化物の合成とその弾性的性質

    丹羽健,鈴木健太郎,長谷川正,Mikhail Eremets,Dmytro Dzivenko,Ralf Riedel

    日本セラミックス協会2013年年会 

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    Event date: 2013.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Country:Japan  

  168. 超高圧高温超臨界水を用いた金属水素化物の合成

    白木達人,近藤広基,山口貫太,丹羽健,加藤政彦,曽田一雄,草場啓治,長谷川正

    日本セラミックス協会2013年年会 

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    Event date: 2013.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京工業大学(大岡山キャンパス)   Country:Japan  

  169. BiFeO3-BiAlO3系およびBiFeO3-MnTiO3系固溶体の高圧合成

    志村元,草場啓治,宮脇哲也,丹羽健,浅野秀文,長谷川正

    日本セラミックス協会2013年年会 

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    Event date: 2013.3

    Language:Japanese   Presentation type:Poster presentation  

    Venue:東京工業大学(大岡山キャンパス)   Country:Japan  

  170. パイライト型Ni1-xCuxS2の電子構造(I):CuS2

    曽田一雄, 臼井健介, 大澤周平, 近藤広基, 加藤政彦, 岩崎純也, 丹羽健, 草場啓治, 長谷川正

    UVSORシンポジウム 

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    Event date: 2012.11

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:岡崎コンファレンスセンター   Country:Japan  

  171. BaNiO₂の高圧相転移

    光森成生, 草場啓治, 丹羽健, 長谷川正

    高圧討論会 

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    Event date: 2012.11

    Language:Japanese   Presentation type:Poster presentation  

    Venue:大阪大学   Country:Japan  

  172. 加圧による3-イソプロピルリンゴ酸脱水素酵素への水分子の侵入:深海微生物の酵素の圧力適応

    永江峰幸, 濱島祐輝, 河村高志, 丹羽健, 長谷川正, 加藤千明, 渡邉信久

    第53回高圧討論会 

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    Event date: 2012.11

    Language:Japanese   Presentation type:Poster presentation  

    Venue:大阪大学   Country:Japan  

  173. 酸化六ホウ素(B₆O)焼結体の作製と熱電特性

    野引浩介, 草場啓治, 丹羽健, 長谷川正, 後藤弘匡, 八木健彦

    第53回高圧討論会 

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    Event date: 2012.11

    Language:Japanese   Presentation type:Poster presentation  

    Venue:大阪大学   Country:Japan  

  174. 高圧高温下でのナノチューブ状窒化炭素の合成

    堀部太嗣, 丹羽健, 岡田卓, 草場啓治, 長谷川正

    第53回高圧討論会 

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    Event date: 2012.11

    Language:English   Presentation type:Poster presentation  

    Venue:大阪大学   Country:Japan  

  175. 高圧高温超臨界水を用いたNb水素化物の合成と表面分析

    白木達人, 丹羽健, 近藤広基, 山口貫太, 加藤政彦, 曽田一雄, 草場啓治, 長谷川正, 池永英司

    第53回高圧討論会 

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    Event date: 2012.11

    Language:Japanese   Presentation type:Poster presentation  

    Venue:大阪大学   Country:Japan  

  176. Mg₂Si 高圧相の合成と熱電特性

    能丸大器, 草場啓治, 丹羽健, 長谷川正, 後藤弘匡, 八木健彦

    第53回高圧討論会 

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    Event date: 2012.11

    Language:Japanese   Presentation type:Poster presentation  

    Venue:大阪大学   Country:Japan  

  177. BiFeO2-BiAlO2固溶体の高温高圧合成

    志村元, 草場啓治, 丹羽健, 長谷川正

    第53回高圧討論会 

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    Event date: 2012.11

    Language:Japanese   Presentation type:Poster presentation  

    Venue:大阪大学   Country:Japan  

  178. 新規Ca-In 系化合物の高圧高温合成と結晶構造

    江口遼, 丹羽健, 草場啓治, 長谷川正

    第53回高圧討論会 

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    Event date: 2012.11

    Language:Japanese   Presentation type:Poster presentation  

    Venue:大阪大学   Country:Japan  

  179. High-pressure-induced water penetration into IPMDH and pressure-adaptation mechanism of the proteins from deep-sea bacteria

    Takayuki Nagae, Yuki Hamajima, Takashi Kawamura, Ken Niwa, Masashi Hasegawa, Chiaki Kato, Nobuhisa Watanabe

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  180. パイライト型NiS₂とCuS₂の高圧合成

    岩崎純也,草場啓治,臼井健介,丹羽健,曽田一雄,長谷川正

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  181. Mg₂Si 高圧相の合成と熱電特性

    能丸大器・草場啓治・丹羽健・長谷川正・後藤弘匡・八木健彦

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  182. 高圧高温超臨界水を用いたNb 水素化物の合成と表面分析

    白木達人・丹羽健・近藤広基・山口貫太・加藤政彦・曽田一雄・草場啓治・長谷川正・池永英司

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  183. ルチル型酸化物(Ti, M)O2ナノチューブ単結晶の創製と分析

    田口鷹志・丹羽健・武藤俊介・草場啓治・長谷川正

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:名古屋大学   Country:Japan  

  184. 新規Ca-In 系化合物の高圧高温合成と結晶構造

    江口遼・丹羽健・草場啓治・長谷川正

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  185. 酸化六ホウ素(B₆O)焼結体の作製と熱電特性

    野引浩介・草場啓治・丹羽健・長谷川正・後藤弘匡・八木健彦

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  186. 高圧高温下でのナノチューブ状窒化炭素の合成

    堀部太嗣・丹羽健・草場啓治・長谷川正

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  187. 高温高圧下における超臨界二酸化炭素の強制還元によるナノカーボンの創製

    小田喬史・飯田雅彦・草場啓治・丹羽健・長谷川正

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  188. 高温超臨界窒素流体を用いた4族窒化物の高圧合成

    鈴木健太郎, 丹羽健, 草場啓治, 長谷川正

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Venue:名古屋大学   Country:Japan  

  189. ZnO-MgO 固溶体の高圧合成

    嶋田大輝・草場啓治・丹羽健・長谷川正

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  190. BaNiO₂の高圧相転移

    光森成生・草場啓治・丹羽健・長谷川正

    日本セラミックス協会第25回秋季シンポジウム 

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    Event date: 2012.9

    Language:Japanese   Presentation type:Poster presentation  

    Country:Japan  

  191. Synthesis of new metal nitride under high pressure and temperature:Exploration for new carbon group nitride International conference

    Ken Niwa

    6th International Workshop on Spinel Nitrides and Related Materials in Conjunction with the Marie Curie ITN 7th Framework Programme FUNEA 

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    Event date: 2012.9

    Language:English   Presentation type:Oral presentation (general)  

    Country:Germany  

  192. 超高圧超臨界流体を用いた中空角柱状ルチル型酸化物の単結晶育成

    丹羽健, 池谷仁志, 田口鷹志, 徳永智春, 草場啓治, 長谷川正

    日本セラミックス協会2012年年会 

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    Event date: 2012.3

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:京都大学   Country:Japan  

  193. 硬X線光電子分光による超臨界水中合成Nb水素化物の化学状態評価

    曽田一雄,近藤広基,野本拓也,森田啓介,加藤政彦,白木達人,丹羽健,長谷川正

    第25回日本放射光学会・放射光科学合同シンポジウム 

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    Event date: 2012.1

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:鳥栖市民文化会館・中央公民館   Country:Japan  

  194. 2-3-2 Pressure-induced phase transformations and elastic properties of nitrogen hydrate

    YONEZAWA Ryohei, KATSUMATA Asa, YASUI Yusuke, KIMURA Tomoaki, SAKATA Masafumi, SASAKI Shigeo, NAGAE Takayuki, NIWA Ken

    Proceedings of the Annual Conference of The Japan Institute of Energy  2023.8.1  The Japan Institute of Energy

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    <p>Nitrogen hydrate (NH) is known to form a cubic structure II (sII), and it successively transforms into a hexagonal structure H (sH) at 0.8 GPa, a tetragonal structure T (sT) at 1.3 GPa, and an orthorhombic structure O (sO) at 1.6 GPa by compression. In this study, high-pressure powder X-ray diffraction and Brillouin scattering measurements have been performed up to 1.7 GPa at room temperature in order to evaluate the pressure-induce phase transformations and the pressure dependence of elastic constants for NH-sH. From the X-ray diffraction measurements, it is found out that the large pressure hysteresis exists at the sII - sH phase change, which probably comes from the smaller guest size compared to the void of 5<sup>12</sup>6<sup>4</sup> water cage. The elastic properties of NH-sH are similar to those of argon hydrate sH.</p>

    DOI: 10.20550/jietaikaiyoushi.32.0_26

    CiNii Research

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Research Project for Joint Research, Competitive Funding, etc. 2

  1. 100万気圧を超える超高圧下でのC3N4の合成とその結合様式および高度の評価

    2012.4 - 2013.3

  2. 物質合成用超高圧高温発生装置の開発と特異な結晶形態を有する新規機能性結晶の創製

    2011.4 - 2012.3

KAKENHI (Grants-in-Aid for Scientific Research) 6

  1. 超緻密窒化物セラミックスの合成と超硬質化メカニズムの解明

    Grant number:22H01771  2022.4 - 2025.3

    日本学術振興会  科学研究費助成事業  基盤研究(B)

    丹羽 健, 劉 崢, 劉 崢

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    Authorship:Principal investigator 

    Grant amount:\17810000 ( Direct Cost: \13700000 、 Indirect Cost:\4110000 )

    超高圧合成法の利点は,高密度相により構成された結晶粒によって空隙が限りなくゼロに近い超緻密な多結晶体が合成される点である.そこで本研究では,世界に先駆けて代表者が発見したSiN2を薄膜で合成し,高度測定および高分解能電子顕微鏡観察から,二窒化物の硬質性と粒界の原子構造との相関を実験的に明らかにし,硬質性セラミックスの新たな学理構築を目指す.

  2. Synthesis and functional development of bulk sintered superhard SiN2

    Grant number:20K21080  2020.7 - 2023.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Challenging Research (Exploratory)

    Niwa Ken

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    Authorship:Principal investigator 

    Grant amount:\6110000 ( Direct Cost: \4700000 、 Indirect Cost:\1410000 )

    In this project, our aim is to synthesize bulk sintered SiN2, the fourth type of silicon nitride, and to elucidate its grain boundary and interface structures as well as mechanical properties. Using a high-pressure press capable of large-volume synthesis, we synthesized γ-Si3N4, the densest polytype of Si3N4, and reacted it with nitrogen under 60 GPa by using a laser-heated diamond anvil cell to successfully synthesize SiN2. In order to elucidate the mechanical properties, a nano-indentation measurement for small-sized nitride sintered under ultra-high pressure was conducted. Although there are some issues to be improved in the synthesis and the evaluation of mechanical properties, we have established a research guideline to elucidate the mechanical properties of ultra-high-pressure materials synthesized under ultra-high pressure.

  3. 希ガス充填型熱電変換材料の開発とラットラー物性の新展開

    2016.4 - 2018.3

    科学研究費補助金 

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    Authorship:Principal investigator 

  4. サブメガバールにおける化学反応が切り開く3d遷移金属多窒化物の結晶化学と電子物性

    2015.4 - 2018.3

    科学研究費補助金  若手研究(A)

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    Authorship:Principal investigator 

  5. ユビキタス元素化合物の超高圧超高温領域における新物質・新結晶の創製

    2010.4 - 2012.3

    科学研究費補助金  特定領域研究,課題番号:22013007

    丹羽 健

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    Authorship:Principal investigator 

  6. 超高温高圧溶融状態からの高密度二酸化物ガラスの合成

    2008.9 - 2010.3

    科学研究費補助金 

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    Authorship:Principal investigator 

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Teaching Experience (On-campus) 61

  1. Mechanics of Continuum

    2022

  2. Mechanics of Continuum

    2022

  3. Experimental Research and Exercises on High pressure materials science A

    2022

  4. Reading and Discussion on Materials Science (High Pressure Materials Science) A

    2022

  5. Seminar on High pressure materials science 1C

    2022

  6. Seminar on High pressure materials science 1A

    2022

  7. Seminar on High pressure materials science 2E

    2022

  8. Seminar on High pressure materials science 2C

    2022

  9. Seminar on High pressure materials science 2A

    2022

  10. 先端材料と物性物理

    2022

  11. 物質科学特別輪講(高圧力物質科学)A

    2020

  12. 物質科学特別輪講(高圧力物質科学)B

    2020

  13. 高圧力物質科学特論

    2020

  14. 高圧力物質科学特別実験及び演習B

    2020

  15. 高圧力物質科学特別実験及び演習A

    2020

  16. 高圧力物質科学セミナー1D

    2020

  17. 高圧力物質科学セミナー1C

    2020

  18. 高圧力物質科学セミナー1B

    2020

  19. 高圧力物質科学セミナー1A

    2020

  20. エネルギーと環境

    2019

  21. 連続体の力学

    2019

  22. 連続体の力学

    2018

  23. 材料工学実験第1

    2018

  24. 高圧力物質科学特論

    2018

  25. エネルギーと環境

    2018

  26. 材料工学実験第1

    2017

  27. 材料工学実験基礎

    2017

  28. 基礎セミナー

    2017

  29. 材料工学実験第2

    2017

  30. エネルギーと環境

    2017

  31. エネルギーと環境

    2016

  32. 材料工学実験基礎

    2016

  33. 結晶物理学基礎

    2016

  34. 材料工学実験第2

    2016

  35. 材料工学実験第1

    2016

  36. 物理工学科概論

    2016

  37. 基礎セミナー

    2016

  38. 高圧力物質科学特論

    2016

  39. 物理工学科概論

    2015

  40. 理系基礎化学実験

    2015

  41. 物理工学科概論

    2014

  42. 材料工学実験第2

    2014

  43. 材料工学実験第1

    2014

  44. 材料工学実験第2

    2013

  45. 材料工学実験第1

    2013

  46. 物理工学科概論

    2013

  47. 材料工学実験第2

    2012

  48. 材料工学実験第1

    2012

  49. 物理工学科概論

    2012

  50. 材料工学実験第1

    2011

  51. 材料工学実験第2

    2011

  52. 物理工学科概論

    2011

  53. 材料工学実験第1

    2010

  54. 材料工学実験第2

    2010

  55. 物理工学科概論

    2010

  56. 材料工学実験第1

    2009

  57. 材料工学実験第2

    2009

  58. 物理工学科概論

    2009

  59. 材料工学実験第1

    2008

  60. 材料工学実験第2

    2008

  61. 物理工学科概論

    2008

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Teaching Experience (Off-campus) 19

  1. Experimental Research and Exercises on High pressure materials science A

    2022 Nagoya University)

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    Level:Postgraduate 

  2. Seminar on High pressure materials science 2E

    2022 Nagoya University)

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    Level:Postgraduate 

  3. Seminar on High pressure materials science 2C

    2022 Nagoya University)

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    Level:Postgraduate 

  4. Seminar on High pressure materials science 2A

    2022 Nagoya University)

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    Level:Postgraduate 

  5. Seminar on High pressure materials science 1C

    2022 Nagoya University)

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    Level:Postgraduate 

  6. Seminar on High pressure materials science 1A

    2022 Nagoya University)

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    Level:Postgraduate 

  7. Mechanics of Continuum

    2022 Nagoya University)

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    Level:Undergraduate (specialized) 

  8. Mechanics of Continuum

    2022 Nagoya University)

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    Level:Undergraduate (specialized) 

  9. Reading and Discussion on Materials Science (High Pressure Materials Science) A

    2022 Nagoya University)

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    Level:Postgraduate 

  10. 先端材料と物性物理

    2022 Nagoya University)

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    Level:Undergraduate (liberal arts) 

  11. 高圧力物質科学特別実験及び演習B

    2020 Nagoya University)

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    Level:Postgraduate 

  12. 高圧力物質科学特別実験及び演習A

    2020 Nagoya University)

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    Level:Postgraduate 

  13. 高圧力物質科学セミナー1D

    2020 Nagoya University)

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    Level:Postgraduate 

  14. 高圧力物質科学セミナー1C

    2020 Nagoya University)

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    Level:Postgraduate 

  15. 高圧力物質科学セミナー1B

    2020 Nagoya University)

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    Level:Postgraduate 

  16. 高圧力物質科学セミナー1A

    2020 Nagoya University)

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    Level:Postgraduate 

  17. 物質科学特別輪講(高圧力物質科学)B

    2020 Nagoya University)

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    Level:Postgraduate 

  18. 物質科学特別輪講(高圧力物質科学)A

    2020 Nagoya University)

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    Level:Postgraduate 

  19. 高圧力物質科学特論

    2020 Nagoya University)

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    Level:Postgraduate 

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