研究者詳細 - 中西　和樹

論文 - 中西　和樹

分割表示 412 件中 81 - 100 件目／全件表示 >>

Preparation of surface-coated macroporous silica (core-shell silica monolith) for HPLC separations: Graphical Abstract 査読有り

Ito, R; Morisato, K; Kanamori, K; Nakanishi, K

JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY 90 巻 ( 1 ) 頁： 105 - 112 2019年4月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Sol-Gel Science and Technology

Abstract: Utilizing the spontaneous wetting of oligomeric silica-phase via phase-separation onto a solid surface in a confined dimension, sub-micrometer thick mesoporous layers have been coated on the surface of nonporous skeletons of preformed macroporous silica gels. The size and volume of mesopores within the layers could be controlled by subsequent aging conditions similarly to those reported for fully porous monolithic silica. Comparison of HPLC efficiencies of these novel type monolithic gels, core-shell silica monoliths, with those of a conventional silica monolith revealed that the retention factor per unit surface area became larger for core-shell silica monoliths. The increase in dynamic accessibility of analyte molecules to the mesopores well explain the improved retention factors in core-shell silica monoliths. [Figure not available: see fulltext.]

DOI： 10.1007/s10971-018-4889-2

Hybrid silicone aerogels toward unusual flexibility, functionality, and extended applications 査読有り

Kanamori, K; Ueoka, R; Kakegawa, T; Shimizu, T; Nakanishi, K

JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY 89 巻 ( 1 ) 頁： 166 - 175 2019年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Sol-Gel Science and Technology

Abstract: Here, we overview the developments in the past decade made on organic–inorganic hybrid aerogels and xerogels based on silicone (polyorganosiloxanes) through persistent works by the authors to increase the mechanical strength and flexibility and add functionality. Polymethylsilsesquioxane (PMSQ, CH3SiO3/2) has been found to show unusual strength and flexibility against compression, and their bending properties can also be improved by several strategies. Silicone-based networks with organic bridges between inorganic moieties are also beneficial for these improvements. In particular, organic bridges with a higher fraction and more extended length have been found to allow higher durability against large deformations. In addition, functional groups such as vinyl, chloromethyl, and amino can readily be introduced by starting from organoalkoxysilanes with these functional substituents (e.g., FG−Si(OR)3 or (RO)3Si−FG−Si(OR)3, where FG shows an organic substituent containing functional groups and R is typically methyl or ethyl), and other functional groups such as carboxyl can be introduced by post-gelation modifications on the pre-installed FG in the network. Possibilities in applications such as thermal insulators, photoluminescent media, and photocatalysts are also discussed. [Figure not available: see fulltext.].

DOI： 10.1007/s10971-018-4804-x

Synthesis of hierarchically porous MgO monoliths with continuous structure via sol-gel process accompanied by phase separation 査読有り

Lu, XM; Kanamori, K; Nakanishi, K

JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY 89 巻 ( 1 ) 頁： 29 - 36 2019年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Sol-Gel Science and Technology

Hierarchically porous magnesium oxide, MgO, monoliths with a well-defined continuous macroporous structure have been synthesized via the sol–gel route accompanied by phase separation. Magnesium chloride hexahydrate was used as a precursor, and propylene oxide was used as an acid scavenger to raise the pH of a reaction solution homogenously. In order to obtain a crack-free monolith after heating in air, poly(vinylpyrrolidone), PVP, was employed as a scaffold of the skeleton as well as a phase separation controller to form the continuous macropores with higher homogeneity. Due to the moderate hydrogen-bonding interaction with magnesium hydroxide, PVP reinforces the gel network essentially composed of fine grained magnesium hydroxide. Even after the removal of all organic components by calcination, the porous gel samples maintained their monolithic form. On the other hand, an additional incorporation of 1,3,5-benzenetricarboxylic acid, H3BTC, was found to be effective in suppressing the oriented growth of the micrometer-sized crystalline phase. The polycrystalline MgO monoliths with specific surface area of 185, 64, and 48 m2 g−1 were prepared after heating at 400, 500, and 600 °C in air, respectively. [Figure not available: see fulltext.].

DOI： 10.1007/s10971-018-4682-2

Uric acid enhances alteplase-mediated thrombolysis as an antioxidant. 査読有り

Kikuchi K, Setoyama K, Tanaka E, Otsuka S, Terashi T, Nakanishi K, Takada S, Sakakima H, Ampawong S, Kawahara KI, Nagasato T, Hosokawa K, Harada Y, Yamamoto M, Kamikokuryo C, Kiyama R, Morioka M, Ito T, Maruyama I, Tancharoen S

Scientific reports 8 巻 ( 1 ) 頁： 15844 2018年10月

Sol-gel preparation of hierarchically porous magnesium aluminate (MgAl<sub>2</sub>O<sub>4</sub>) spinel monoliths for dye adsorption 査読有り

Guo, XZ; Yin, PA; Kanamori, K; Nakanishi, K; Yang, H

JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY 88 巻 ( 1 ) 頁： 114 - 128 2018年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Sol-Gel Science and Technology

Abstract: Hierarchically porous spinel-type binary metal oxide MgAl2O4 with cocontinuous skeletons and interconnected macropores has been synthesized by a facile sol–gel method accompanied by phase separation, in which poly (ethylene oxide) (PEO) works as phase separation inducer to form micrometer-scale phase-separated macrochannels at the same time of sol–gel transition. The obtained xerogels exhibit in the form of a monolith with well-defined macropores and cocontinuous dense skeletons by adjusting the amount of PEO. The xerogel and those heat-treated at or below 600 °C are amorphous, and heat-treatment at or above 700 °C allows the precipitation of complete crystalline MgAl2O4 spinel with a macropore size of 0.7–0.9 μm, a porosity of 60–70%, and a BET surface area of 40–80 m2 g−1, without spoiling the macrostructure of monoliths. Three anionic dyes and two cationic dyes are selected as targeted adsorbates to investigate the selective adsorption ability of a hierarchically porous MgAl2O4 spinel. The resultant MgAl2O4 spinel shows a high affinity and adsorption rate toward anionic dyes Congo Red, Methyl Orange, and Methyl Blue. The maximum adsorption capacity of MgAl2O4 spinel toward these three anionic dyes are 2721.6 mg g−1 for Congo Red, 2469.7 mg g−1 for Methyl Orange, and 6771.9 mg g−1 for Methyl Blue, respectively. [Figure not available: see fulltext.]

DOI： 10.1007/s10971-018-4781-0

The gravitationally unstable gas disk of a starburst galaxy 12 billion years ago 査読有り

Tadaki K., Iono D., Yun M.S., Aretxaga I., Hatsukade B., Hughes D.H., Ikarashi S., Izumi T., Kawabe R., Kohno K., Lee M., Matsuda Y., Nakanishi K., Saito T., Tamura Y., Ueda J., Umehata H., Wilson G.W., Michiyama T., Ando M., Kamieneski P.

Nature 560 巻 ( 7720 ) 頁： 613 - 616 2018年8月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Nature

Galaxies in the early Universe that are bright at submillimetre wavelengths (submillimetre-bright galaxies) are forming stars at a rate roughly 1,000 times higher than the Milky Way. A large fraction of the new stars form in the central kiloparsec of the galaxy1–3, a region that is comparable in size to the massive, quiescent galaxies found at the peak of cosmic star-formation history4 and the cores of present-day giant elliptical galaxies. The physical and kinematic properties inside these compact starburst cores are poorly understood because probing them at relevant spatial scales requires extremely high angular resolution. Here we report observations with a linear resolution of 550 parsecs of gas and dust in an unlensed, submillimetre-bright galaxy at a redshift of z = 4.3, when the Universe was less than two billion years old. We resolve the spatial and kinematic structure of the molecular gas inside the heavily dust-obscured core and show that the underlying gas disk is clumpy and rotationally supported (that is, its rotation velocity is larger than the velocity dispersion). Our analysis of the molecular gas mass per unit area suggests that the starburst disk is gravitationally unstable, which implies that the self-gravity of the gas is stronger than the differential rotation of the disk and the internal pressure due to stellar-radiation feedback. As a result of the gravitational instability in the disk, the molecular gas would be consumed by star formation on a timescale of 100 million years, which is comparable to gas depletion times in merging starburst galaxies5.

DOI： 10.1038/s41586-018-0443-1

On-line Redox Derivatization Liquid Chromatography Using a Carbon Monolithic Column 査読有り

Miyashita Ken, Tanaka Ryo, Hasegawa George, Nakanishi Kazuki, Morioka Kazuhiro, Zeng Hulie, Kato Shungo, Uchiyama Katsumi, Saitoh Kazunori, Shibukawa Masami, Nakajima Hizuru

BUNSEKI KAGAKU 67 巻 ( 8 ) 頁： 469 - 478 2018年8月

Synthesis of a hierarchically porous niobium phosphate monolith by a sol-gel method for fructose dehydration to 5-hydroxymethylfurfural 査読有り

Gao, DM; Zhao, BH; Liu, HC; Morisato, K; Kanamori, K; He, ZY; Zeng, MM; Wu, HP; Chen, J; Nakanishi, K

CATALYSIS SCIENCE & TECHNOLOGY 8 巻 ( 14 ) 頁： 3675 - 3685 2018年7月

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

Hierarchically porous niobium phosphate (NbP) was synthesised via a sol-gel method accompanied by phase separation and employed as a catalyst for fructose dehydration. The niobium precursor was prepared by digesting ammonium niobate(v) oxalate in aqueous H2O2 with citric acid as a chelating agent to prevent the precipitation of niobium hydroxide. Poly(acrylamide) and poly(ethylene glycol) were used as phase separation inducers to produce co-continuous macropores and gel skeletons. The NbP sample calcined at 600 °C for 8 h had a high surface area (SBET ∼140 m2 g-1) and large acidity (0.84 mmol-NH3 g-1). The NbP monolith was amorphous after calcination at 600 °C and transformed into an α-NbOPO4 phase at 1000 °C. The NbP monolith calcined at 600 °C was an efficient acid catalyst for the dehydration of fructose to 5-hydroxymethylfurfural in water (70% yield) or in aqueous dimethyl sulfoxide (90% yield). The productivity of HMF reached 7.3 × 10-2 mol h-1 per kg-solution at an initial fructose concentration of 10.0 wt% in water with a catalyst loading of 2.0 wt%.

DOI： 10.1039/c8cy00803e

Comprehensive studies on phosphoric acid treatment of porous titania toward titanium phosphate and pyrophosphate monoliths with pore hierarchy and a nanostructured pore surface 査読有り

Zhu Y., Hasegawa G., Kanamori K., Nakanishi K.

Inorganic Chemistry Frontiers 5 巻 ( 6 ) 頁： 1397 - 1404 2018年6月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Inorganic Chemistry Frontiers

Simple post-treatments of the porous titania monolith in varied concentrations of phosphoric acid solution provide a series of monolithic titanium phosphates (TiPs) with a hierarchically porous structure together with an exquisite macropore surface. Depending on the reaction conditions, platy crystallites composed of either Ti2O3(H2PO4)2·2H2O, Ti(HPO4)2·H2O (α-TiP), or Ti2O(PO4)2·2H2O (π-TiP) are generated on the macropore skeleton via a dissolution and reprecipitation process, which forms distinct wrinkled surface morphologies. In addition, the treatments effectively suppress the shrinkage during drying, leading to lower bulk density. Post-calcination in air yields porous titanium pyrophosphates preserving the intricate porous architecture in some cases. Notably, the hierarchically porous TiP2O7 monoliths prepared from the α-TiP precursors have a good thermal robustness related to bulk density.

DOI： 10.1039/c8qi00146d

Iron(III) oxyhydroxide and oxide monoliths with controlled multiscale porosity: synthesis and their adsorption performance 査読有り

Hara, Y; Kanamori, K; Morisato, K; Miyamoto, R; Nakanishi, K

JOURNAL OF MATERIALS CHEMISTRY A 6 巻 ( 19 ) 頁： 9041 - 9048 2018年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Materials Chemistry A

Iron(iii) oxyhydroxide and oxide monoliths with controlled multiscale porosity have been successfully fabricated via the sol-gel process accompanied by phase separation. The size of macropores was controlled by synthesis parameters such as starting compositions. The as-dried iron(iii) oxyhydroxide monoliths were amorphous and possessed surface areas over 340 m2 g-1, of which mesostructures could be further controlled by a heat-treatment at 250-350 °C without collapse of macrostructures and monolithic forms. When the as-dried gel was heated at 300 °C, the resultant gel transformed to crystalline α-Fe2O3 and exhibited a specific surface area of 124 m2 g-1. Heat-treatment at 350 °C resulted in the broadened size distribution of mesopores. The adsorption behavior of Congo red has revealed that the interconnected macroporous structure contributed to faster diffusion and better accessibility in a continuous flow-through set up, and the crack-free monolithic forms accounted for an advantageous use of the flow-through adsorbents.

DOI： 10.1039/c8ta01691g

Versatile Double-Cross-Linking Approach to Transparent, Machinable, Supercompressible, Highly Bendable Aerogel Thermal Superinsulators 査読有り

Zu, GQ; Kanamori, K; Shimizu, T; Zhu, Y; Maeno, A; Kaji, H; Nakanishi, K; Shen, J

CHEMISTRY OF MATERIALS 30 巻 ( 8 ) 頁： 2759 - 2770 2018年4月

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

A facile yet versatile approach to transparent, highly flexible, machinable, superinsulating organic-inorganic hybrid aerogels is presented. This method involves radical polymerization of a single alkenylalkoxysilane to obtain polyalkenylalkoxysilane, and subsequent hydrolytic polycondensation to afford a homogeneous, doubly cross-linked nanostructure consisting of polysiloxanes and hydrocarbon polymer units. Here we demonstrate that novel aerogels based on polyvinylpolysilsesquioxane (PVPSQ), polyallylpolysilsesquioxane (PAPSQ), polyvinylpolymethylsiloxane (PVPMS), and polyallylpolymethylsiloxane (PAPMS) are facilely prepared via this approach from vinyltrimethoxysilane (VTMS; or vinyltriethoxysilane, VTES), allyltrimethoxysilane (ATMS; or allyltriethoxysilane, ATES), vinylmethyldimethoxysilane (VMDMS), and allylmethyldimethoxysilane (AMDMS), respectively. These aerogels combine low density, uniform nanopores, high transparency, supercompressibility, high bendability, excellent machinability, and thermal superinsulation (λ = 14.5-16.4 mW m-1 K-1). More importantly, transparent, superflexible, superinsulating aerogels are obtained with PVPMS and PAPMS via highly scalable ambient pressure drying without any solvent-exchange and modifications for the first time. This work will open a new way to transparent, highly flexible porous materials, promising in the practical applications of thermal superinsulators, adsorbents, sensors, etc.

DOI： 10.1021/acs.chemmater.8b00563

Transparent, Superflexible Doubly Cross-Linked Polyvinylpolymethylsiloxane Aerogel Superinsulators via Ambient Pressure Drying 査読有り

Zu, GQ; Shimizu, T; Kanamori, K; Zhu, Y; Maeno, A; Kaji, H; Shen, J; Nakanishi, K

ACS NANO 12 巻 ( 1 ) 頁： 521 - 532 2018年1月

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

Aerogels have many attractive properties but are usually costly and mechanically brittle, which always limit their practical applications. While many efforts have been made to reinforce the aerogels, most of the reinforcement efforts sacrifice the transparency or superinsulating properties. Here we report superflexible polyvinylpolymethylsiloxane, (CH2CH(Si(CH3)O2/2))n, aerogels that are facilely prepared from a single precursor vinylmethyldimethoxysilane or vinylmethyldiethoxysilane without organic cross-linkers. The method is based on consecutive processes involving radical polymerization and hydrolytic polycondensation, followed by ultralow-cost, highly scalable, ambient-pressure drying directly from alcohol as a drying medium without any modification or additional solvent exchange. The resulting aerogels and xerogels show a homogeneous, tunable, highly porous, doubly cross-linked nanostructure with the elastic polymethylsiloxane network cross-linked with flexible hydrocarbon chains. An outstanding combination of ultralow cost, high scalability, uniform pore size, high surface area, high transparency, high hydrophobicity, excellent machinability, superflexibility in compression, superflexibility in bending, and superinsulating properties has been achieved in a single aerogel or xerogel. This study represents a significant progress of porous materials and makes the practical applications of transparent flexible aerogel-based superinsulators realistic.

DOI： 10.1021/acsnano.7b07117

On-line redox derivatization liquid chromatography using a carbon monolithic column 査読有り

Miyashita K., Tanaka R., Hasegawa G., Nakanishi K., Morioka K., Zeng H., Kato S., Uchiyama K., Saitoh K., Shibukawa M., Nakajima H.

Bunseki Kagaku 67 巻 ( 8 ) 頁： 469 - 478 2018年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Bunseki Kagaku

A macroporous resorcinol-formaldehyde (RF) xerogel was synthesized via sol–gel reaction, accompanied by phase separation; a graphitized carbon monolith was then prepared by calcining the RF xerogel at a relatively low temperature (1200 °C) utilizing catalytic graphitization. The retention behaviors of metal-EDTA complexes on the carbon monolithic column were investigated. The carbon monolith exhibited catalytic activity for redox reactions, like porous graphitic carbon packing materials do; they oxidized Co(II)-EDTA to Co(III)-EDTA during elution. Their redox activity could be modified by treating with an eluent containing an oxidizing or reducing agent. A novel on-line redox derivatization HPLC system using a carbon monolithic column was developed for enhancing the separation selectivity. This on-line redox derivatization HPLC system consisted of two ODS columns as a separation column and one carbon monolithic column as redox derivatization unit placed between them. The Co(II)-EDTA migrated as its original oxidation state in the first ODS column, while it migrated as Co(III)-EDTA in the second ODS column, since Co(II)-EDTA was rapidly oxidized to Co(III)-EDTA in the carbon monolithic column. On the other hand, other metal-EDTA complexes migrated as their original oxidation states in these columns. Therefore, the Co-EDTA could be separated from the other metal-EDTA complexes. This on-line redox derivatization HPLC system was successfully used for determining the trace amount of cobalt in a reference copper alloy.

DOI： 10.2116/bunsekikagaku.67.469

The effect of exercise frequency on neuropathic pain and pain-related cellular reactions in the spinal cord and midbrain in a rat sciatic nerve injury model. 査読有り

Sumizono M, Sakakima H, Otsuka S, Terashi T, Nakanishi K, Ueda K, Takada S, Kikuchi K

Journal of pain research 11 巻頁： 281 - 291 2018年

Synthesis and characterization of monolithic ZnAl<sub>2</sub>O<sub>4</sub> spinel with well-defined hierarchical pore structures via a sol-gel route 査読有り

Guo, XZ; Yin, PA; Lei, W; Yang, H; Kanamori, K; Nakanishi, K

JOURNAL OF ALLOYS AND COMPOUNDS 727 巻頁： 763 - 770 2017年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Alloys and Compounds

Hierarchically porous ZnAl2O4 spinel monolith derived from ionic precursors has been successfully prepared via the sol-gel route accompanied by phase separation in the presence of poly (ethylene oxide) (PEO) and propylene oxide (PO). Appropriate amounts of PEO as a phase-separation inducer and PO as a gelation mediator allow the formation of the xerogel with bicontinuous macrostructure and a monolithic shape. The macropore size of the resultant dried gel is mainly distributed in the range of 0.2–1 μm, and the whole porosity is about 65%. The dried gel is constructed by crystalline Zn–Al hydrotalcite, becoming amorphous after heat-treated at 300–500 °C in air, and is further transformed into single phase ZnAl2O4 spinel with plate-like shape at 600 °C. The macroporous structure is well maintained while the porosity increases to 75% and the surface area rises to 109 m2 g−1 after heat-treatment.

DOI： 10.1016/j.jallcom.2017.08.172

Aerogels from Chloromethyltrimethoxysilane and Their Functionalizations 査読有り

Kimura, T; Shimizu, T; Kanamori, K; Maeno, A; Kaji, H; Nakanishi, K

LANGMUIR 33 巻 ( 48 ) 頁： 13841 - 13848 2017年12月

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

Reactions of chloromethyltrimethoxysilane (CMTMS) and its derived colloidal network polychloromethylsilsesquioxane (PCMSQ) have been investigated to extend the material design strategy toward functionalized and mechanically reinforced aerogels. In a carefully designed sol-gel system, CMTMS has afforded transparent aerogels in the presence of cationic surfactant. The surface chloromethyl groups with polarity and reactivity are shown to be useful for supporting nanostructures, with photoluminescent carbon dots (C-dots) prepared from polyethylenimine and citric acid as an example. Furthermore, since nucleophilic substitution (SN2) reactions on the surface chloromethyl groups are found to control the equilibrium of formation/dissociation of siloxane bonds, a new gelation strategy triggered by SN2 reactions in sol-gel has been developed. In the presence of nucleophilic organic species such as polyamines, a hybrid network consisting of PCMSQ cross-linked with a polyamine nucleophile can be prepared to enhance mechanical properties of aerogel.

DOI： 10.1021/acs.langmuir.7b03013

Polymer-assisted shapeable synthesis of porous frameworks consisting of silica nanoparticles with mechanical property tuning 査読有り

Sato, K; Ishii, K; Oaki, Y; Nakanishi, K; Imai, H

POLYMER JOURNAL 49 巻 ( 12 ) 頁： 825 - 830 2017年12月

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

We report the shapeable synthesis of porous silica frameworks using polyacrylamide (PAAm) gel as an organic template and hydrolyzed silicon alkoxide as a silica source. Macroscopically shaped porous frameworks - such as plates, tablets and sheets - comprised of 20- to 40-nm diameter silica particles are obtained via PAAm-silica precursor gels. The mechanical properties (i.e., hardness and Young's modulus) of the silica frameworks depend on the packing density and are controlled by changing the silica content in PAAm gels.

DOI： 10.1038/pj.2017.62

Very Compact Millimeter Sizes for Composite Star-forming/AGN Submillimeter Galaxies 査読有り

Ikarashi S., Caputi K.I., Ohta K., Ivison R.J., Lagos C.D.P., Bisigello L., Hatsukade B., Aretxaga I., Dunlop J.S., Hughes D.H., Iono D., Izumi T., Kashikawa N., Koyama Y., Kawabe R., Kohno K., Motohara K., Nakanishi K., Tamura Y., Umehata H., Wilson G.W., Yabe K., Yun M.S.

Astrophysical Journal Letters 849 巻 ( 2 ) 2017年11月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Astrophysical Journal Letters

We report the study of the far-infrared (IR) sizes of submillimeter galaxies (SMGs) in relation to their dustobscured star formation rate (SFR) and active galactic nuclei (AGN) presence, determined using mid-IR photometry. We determined the millimeter-wave (λobs = 1100 μm) sizes of 69 Atacama Large Millimeter/ submillimeter Array (ALMA)-identified SMGs, selected with ≥10 δ confidence on ALMA images (F1100 μm = 1.7-7.4 mJy). We found that all of the SMGs are located above an avoidance region in the sizeflux plane, as expected by the Eddington limit for star formation. In order to understand what drives the different millimeter-wave sizes in SMGs, we investigated the relation between millimeter-wave size and AGN fraction for 25 of our SMGs at z=1-3. We found that the SMGs for which the mid-IR emission is dominated by star formation or AGN have extended millimeter-sizes, with respective median Rc,e = 1.6-0.21+0.34 and 1.5 -0.24+0.93 kpc. Instead, the SMGs for which the mid-IR emission corresponds to star-forming/AGN composites have more compact millimeter-wave sizes, with median Rc,e1.0 -0.20+0.20kpc. The relation between millimeter-wave size and AGN fraction suggests that this size may be related to the evolutionary stage of the SMG. The very compact sizes for composite star-forming/AGN systems could be explained by supermassive black holes growing rapidly during the SMG coalescing, star-formation phase.

DOI： 10.3847/2041-8213/aa9572

Synthesis, Reduction, and Electrical Properties of Macroporous Monolithic Mayenite Electrides with High Porosity 査読有り

Wang, R; Yang, H; Lu, YH; Kanamori, K; Nakanishi, K; Guo, XZ

ACS OMEGA 2 巻 ( 11 ) 頁： 8148 - 8155 2017年11月

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

Room-temperature stable macroporous mayenite electride (C12A7:e-) has been successfully prepared via a sol-gel method accompanied by phase separation, followed by heat-treatment and reduction processes. The obtained xerogel monoliths possess controllable macrostructure and a porosity of more than 60%, depending on adjusting the amount of poly(ethylene oxide) as a phase separation inducer. Heat-treatment allows the formation of multicrystals Ca12Al14O32Cl2 and Ca12Al14O33 (C12A7), and the porosity increases to 78.67% after being heat-treated at 1100 °C. Further reduction promotes the transformation from Ca12Al14O32Cl2 or C12A7 to C12A7:e- as well as the conversion from an insulator to a semiconductive electride. The carrier concentration of the electride reaches 3.029 × 1018 cm-3 after being reduced at 1100 °C under Ar atmosphere, and the porosity still remains 66%. The macrostructure of the resultant mayenite electride before and after heat-treatment and reduction is perfectly preserved, indicating that the obtained macroporous monolithic mayenite electride could be utilized in the electronic components.

DOI： 10.1021/acsomega.7b01121

Aerogels from chloromethyltrimethoxysilane and their functionalizations 査読有り

Tomoki KIMURA, Taiyo SHIMIZU, Kazuyoshi KANAMORI, Ayaka MAENO, Hironori KAJI, Kazuki NAKANISHI

Langumuir 2017年11月

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