研究者詳細 - 亀島　欣一

MISC - 亀島　欣一

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Asian Clay報告

亀島欣一, 川俣純, 高木慎介, 松枝直人, 福士圭介, 山田裕久

粘土科学 49 ( 2 ) 53 - 61 2010年

光応答デンドリマー/層状複水酸化物複合体の合成と取込量に対するpHの影響

田中俊行, 西本俊介, 亀島欣一, 高口豊, 三宅通博

粘土科学討論会講演要旨集 54th 2010年

LbL法を用いたLDH/機能性デンドリマーハイブリッド薄膜の作製

田中俊行, 西本俊介, 亀島欣一, 高口豊, 三宅通博

セラミックス基礎科学討論会講演要旨集 48th 2010年

層状複水酸化物のデンドリマーに対するイオン交換特性;pH応答性

田中俊行, 西本俊介, 亀島欣一, 高口豊, 三宅通博

日本化学会講演予稿集 90th ( 2 ) 2010年

Nanosized silver-anionic clay matrix as nanostructured ensembles with antimicrobial activity

Gabriela Carja, Yoshikazu Kameshima, Akira Nakajima, Cristian Dranca, Kiyoshi Okada

INTERNATIONAL JOURNAL OF ANTIMICROBIAL AGENTS 34 ( 6 ) 534 - 539 2009年12月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

Nanostructured ensembles of silver nanoparticles/zinc-substituted anionic clay matrix (Ag/ZnLDH) were obtained by a simple synthetic route in which reconstruction of the layered clay, synthesis of the silver nanoparticles and their organisation on the clay surface took place in a single step at room temperature. The morphology, composition and phase structure of the prepared powders were characterised by X-ray diffraction, infrared spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and N(2) adsorption. Results showed that the silver-anionic clay nanoarchitecture consists of nanoparticles of silver (average size 7 nm) deposited on the larger nanoparticles of clay (average size 85 nm). The antimicrobial activity was examined by disk diffusion assay and minimal inhibitory concentration determination as a function of x, where x is a controlled variable parameter that represents the length of time since the sample was synthesised. Ag/ZnLDH showed more stable antimicrobial properties than the unsupported nanosized silver. (C) 2009 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

DOI： 10.1016/j.ijantimicag.2009.08.008

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Preparation of Pt particles dispersing nanocomposites by thermal treatment of tetrachloroplatinate/layered double hydroxide (LDH)

Yoshikazu Kameshima, Akira Nakajima, Kiyoshi Okada, Toyohiko Yano

JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 117 ( 1371 ) 1229 - 1232 2009年11月

記述言語：英語出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI

Mg-Al LDH intercalated PtCl42- anion (PtCl4-LDH) was synthesized by a reconstruction method using potassium tetrachloroplatinate and its thermal changes were investigated at various temperatures. The PtCl4-LDH included 17 mass% Pt was synthesized by a reconstruction method using K2PtCl4 Solution of 10 mM to adjust the pH with NaOH to about 11. The obtained PtCl4-LDH shows high crystallinity and has low content of CO32-. The basal spacing of the obtained PtCl4-LDH was 0.83 nm expanding slightly from 0.78 nm of starting LDH. The XRD patterns of the obtained PtCl4-LDH showed that the second 001 diffraction line (006) became more accentuated than the first one (003) according to the intercalation of Pt components. Pt fine particles in the several nm were directly observed by TEM after firing at 500 degrees C. However, the diffraction patterns of Pt or Pt components were not detected via XRD in the same sample. This is due to the coagulation of Pt components by the narrow basal spacing of the PtCl4-LDH. (C) 2009 The Ceramic Society of Japan, All rights reserved.

DOI： 10.2109/jcersj2.117.1229

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Solid acidities of SiO2-TiO2/montmorillonite composites synthesized under different pH conditions

Yoshikazu Kameshima, Akihiro Yoshizawa, Akira Nakajima, Kiyoshi Okada

APPLIED CLAY SCIENCE 46 ( 2 ) 181 - 184 2009年10月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

SiO2-TiO2/montmorillonite composites were prepared under acidic. neutral and basic conditions and the solid acidity of the resulting composites were determined. All the SiO2/TiO2. ratio of the colloidal particles was set at 10 but the resulting SiO2/TiO2 ratios were significantly richer in TiO2. The XRD patterns of the acidic composite showed expanding and broadening of the (001) reflection by intercalation of colloidal SiO2-TiO2 particles. but the neutral and basic composites showed only broadening of the reflections and no intercalation. The specific surface areas of the acidic. neutral and basic composites (375, 237 and 247 m(2)/g, respectively) were much larger than of montmorillonite (6 m(2)/g). The average pore sizes were about 4.15 and 50 nm. and the amounts of solid acidic sites measured by the NH3-TPD were 178, 95 and 86 mu mol/g for the acidic. neutral and basic composites, respectively. The solid acid amount of the acidic composite was twice that of a commercial catalyst, K-10, (85 mu mol/g) and much higher than the guest phase SiO2-TiO2 gel (16 mu mol/g) or the host phase montmorillonite (6 mu mol/g). The TPD peak temperatures reflect the acid strength, and were similar in all the samples, ranging from 175 degrees to 200 degrees C. (C) 2009 Elsevier B.V. All rights reserved

DOI： 10.1016/j.clay.2009.08.001

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Preparation and photocatalytic activity of Keggin-ion tungstate and TiO2 hybrid layer-by-layer film composites

Sayaka Yanagida, Akira Nakajima, Takayoshi Sasaki, Toshihiro Isobe, Yoshikazu Kameshima, Kiyoshi Okada

Applied Catalysis A: General 366 ( 1 ) 148 - 153 2009年9月

記述言語：英語

Keggin ions (PW12O403- (PW12), SiW12O404- (SiW12), H2W12O406- (H2W12)) and TiO2 hybrid thin films were prepared using the layer-by-layer method. Their photocatalytic activities were investigated using gaseous 2-propanol decomposition. All films were transparent in the visible wavelength range. For 2-propanol decomposition, H2W12 was the most effective for the combination with TiO2 despite having the smallest TiO2 deposition amount. The photocatalytic activity of the PW12-TiO2 hybrid film was increased 2.3 times by visible light with UV illumination. This increase was less remarkable for hybrid films of other Keggin ions, suggesting that the visible light excitation of reduced PW12 plays an important role in the enhancement of 2-propanol decomposition. © 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.apcata.2009.06.046

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P31 イブプロフェン/層状複水酸化物の作製とイブプロフェンの放出挙動の調査(ポスター発表,一般講演)

桜田雄, 亀島欣一, 磯部敏宏, 中島章, 岡田清

粘土科学討論会講演要旨集 ( 53 ) 196 - 197 2009年9月

B18 Gallate(没食子酸)/層状複水酸化物複合体の作製と評価(口頭発表,一般講演)

亀島欣一, 西本俊介, 三宅通博

粘土科学討論会講演要旨集 ( 53 ) 102 - 103 2009年9月

Measurement of non-DLVO force on a silicon substrate coated with ammonium poly(acrylic acid) using scanning probe microscopy

Toshihiro Isobe, Yosuke Nakano, Yoshikazu Kameshima, Akira Nakajima, Kiyoshi Okada

APPLIED SURFACE SCIENCE 255 ( 20 ) 8710 - 8713 2009年7月

記述言語：英語掲載種別：速報，短報，研究ノート等（学術雑誌）出版者・発行元：ELSEVIER SCIENCE BV

The repulsive force originating from steric hindrance of polymers in aqueous solvent was investigated using scanning probe microscopy (SPM). The contact angle (CA) of ammonium poly(acrylic acid) (PAA) solution on the Si surface was measured to estimate the state of the Si substrate. Results of CA measurement show that the Si surface was fully covered with PAA at 0.1 mass% in aqueous solution. The interaction force between the Si tip and the wafer was estimated using the SPM force curve mode. The force curve measured in the ion-exchanged purified water showed the typical relation predicted by Derjaguin-Landau-Verway-Overbeek (DLVO) theory. However, the force curve shape in the 0.1 mass% PAA solution was significantly different. Only a repulsive force was observed at less than about 4 nm of separation distance between the Si wafer and cantilever tip. This distance originated from the steric repulsions of PAA adsorbed onto the Si wafer and cantilever tip. Crown Copyright (C) 2009 Published by Elsevier B. V. All rights reserved.

DOI： 10.1016/j.apsusc.2009.06.050

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Preparation of solid acid carbon coating on the surface of TiO2 by photo-CVD of gaseous aromatic hydrocarbons

Akira Nakajima, Katsuhiro Horie, Michikazu Hara, Masaaki Kitano, Toshihiro Isobe, Yoshikazu Kameshima, Kiyoshi Okada

CATALYSIS COMMUNICATIONS 10 ( 13 ) 1670 - 1673 2009年7月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

Properties of a solid acid carbon coating prepared on TiO2 powder surface using photochemical vapor deposition (photo-CVD) were evaluated. The TiO2 powder surface became brown during UV illumination under a flowing xylene and xylene sulfonic acid mixture. Observation by TEM revealed an amorphous carbon coating on the TiO2 powder. Sulfonate groups were identified on the coating using FT-IR. A chart of NH3-TPD measurements showed two peaks: that at high temperature was attributed to the coating's strong acid. The carbon coating's acidity was equivalent to that of the solid superacid carbon powder and the carbon-coated TiO2 decomposed cellulose. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.catcom.2009.05.006

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Water retention properties of porous geopolymers for use in cooling applications

Kiyoshi Okada, Asami Ooyama, Toshihiro Isobe, Yoshikazu Kameshima, Akira Nakajima, Kenneth J. D. MacKenzie

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 29 ( 10 ) 1917 - 1923 2009年7月

記述言語：英語出版者・発行元：ELSEVIER SCI LTD

A series of geopolymers were prepared with varying ratios of sodium silicate, metakaolinite, NaOH and H(2)O and their porous properties, water retention and mechanical properties were determined, to develop materials for counteracting heat island effects. Samples were prepared with the molar ratios SiO(2):Al(2)O(3):Na(2)O:H(2)O of 3.66:1:x:y, where x = 0.92-1.08 and y = 14.2-19.5. The porous and mechanical properties of the geopolymers showed a good correlation with the H(2)O/Al(2)O(3) ratio (y); an increase in y produced an increase in the pore volume (from 0.26 to 0.46 ml/g), the pore size (from 15 to 390 nm) and the water absorption (from 27.2 to 51.1%). The same increase in y decreased the bulk density (from 1.29 to 0.99 g/cm(3)), the bending strength (from 14.2 to <5 MPa) and the water retention. Thus, the H(2)O/Al(2)O(3) ratio is the most important factor for controlling the porous properties of these materials, since geopolymers with higher H(2)O/Al(2)O(3) ratios are more porous and have higher water absorption rates, making them suitable as materials for surface cooling by water evaporation. Geopolymers with lower H(2)O/Al(2)O(3) ratios are more suitable for water retention applications, and have the advantage of higher mechanical strength. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2008.11.006

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Preparation and properties of TiO2/montmorillonite composites

Yoshikazu Kameshima, Yoshihiro Tamura, Akira Nakajima, Kiyoshi Okada

APPLIED CLAY SCIENCE 45 ( 1-2 ) 20 - 23 2009年6月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

TiO2/montmorillonite composites were prepared by reaction of montmorillonite with a TiO2 Sol formed by hydrolyzing titanium iso-propoxide, at 50-80 degrees C. The composites showed expanding and broadening of the basal reflections of montmorillonite indicating a partial intercalation of the smaller colloidal TiO2 particles and increased disorder. The reaction temperature affected largely the amount of TiO2 hydrolyzed and the resulting pore sizes. Both properties increased with increasing reaction temperature: the TiO2 content from 24.2 to 46.6 mass% and the average pore size from 2 to 20 nm. The colloidal TiO2 particles consisted of anatase up to 1000 degrees C without transforming into rutile. The growth of the TiO2 particles was suppressed by the montmorillonite particles. Adsorption of methylene blue (MB) was higher in the composite prepared at 80 degrees C than in that at 50 degrees C because of the larger pore size. Photocatalytic decomposition of 1,4-dioxane by the composites was higher than for pure anatase due to the synergy effect of adsorption for 1,4-dioxane and photodecomposed intermediates by montmorillonite and its photodecomposition by TiO2. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.clay.2009.03.005

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Droplet Size Dependence of Line Tension for an Ionic Liquid on a Smooth Silane Coating

Tsutomu Furuta, Akira Nakajima, Munetoshi Sakai, Toshihiro Isobe, Yoshikazu Kameshima, Kiyoshi Okada

CHEMISTRY LETTERS 38 ( 6 ) 580 - 581 2009年6月

記述言語：英語出版者・発行元：CHEMICAL SOC JAPAN

Line tension was measured for microliter-scale and subnanoliter-scale droplets of an ionic liquid on a highly smooth and homogeneous fluoroalkylsilane coating. Values for microliter-scale droplets were two orders larger than those for subnanoliter-scale droplets despite their identical combinations of solid surfaces and liquid. Scale factors related to this measurement and hydrostatic pressure from the liquid play an important role in the discrepancy.

DOI： 10.1246/cl.2009.580

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Evaporation and Sliding of Water Droplets on Fluoroalkylsilane Coatings with Nanoscale Roughness

Tsutomu Furuta, Akira Nakajima, Munetoshi Sakai, Toshihiro Isobe, Yoshikazu Kameshima, Kiyoshi Okada

LANGMUIR 25 ( 10 ) 5417 - 5420 2009年5月

記述言語：英語出版者・発行元：AMER CHEMICAL SOC

Evaporation and sliding behaviors of water droplets were investigated on smooth and rough fluoroalkylsilane coatings. The rough coating possesses nanoscale roughness and chemical heterogeneity on its surface. Evaporation behaviors for these two coatings differed when nanoliter-scale droplets were used, although they were nearly identical for rnicroliter-scale droplets. The droplets on the smooth coating exhibit greater sliding acceleration and a larger slipping velocity ratio than those on the rough coating. Both the evaporation behavior of nanoliter-scale droplets and sliding velocity of microliter-scale droplets were affected by nanoscale surface heterogeneity. They are indicators for highly homogeneous smooth silane coatings.

DOI： 10.1021/la8040665

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Preparation and abrasion resistance of transparent super-hydrophobic coating by combining crater-like silica films with acicular boehmite powder

Tomoki Yanagisawa, Akira Nakajima, Munetoshi Sakai, Yoshikazu Kameshima, Kiyoshi Okada

MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS 161 ( 1-3 ) 36 - 39 2009年4月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

A super-hydrophobic coating was prepared by combining a rigid base film with crater-like hemispherical holes and acicular nanoparticles. The acicular boehmite powder provides a high contact angle on the film surface. The rigid base film with crater-like hemispherical holes inhibits the rapid decrease of contact angle by surface rubbing. The combination of different roughness is an effective method for improving the abrasion resistance of super-hydrophobic films. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.mseb.2008.11.016

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Dependence of photoinduced surface friction force variation on UV intensity and atmosphere in polycrystalline TiO2 thin films

Naoki Arimitsu, Akira Nakajima, Toshiya Watanabe, Yoshikazu Kameshima, Kiyoshi Okada

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 203 ( 2-3 ) 155 - 160 2009年4月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE SA

Anatase polycrystalline thin films and a plasma crystallization process were used to investigate the dependence of the photoinduced friction force variation for a TiO2 Surface on the UV intensity and atmosphere. Photoinduced friction force variation for UV illumination time was divisible into two stages, decreasing and increasing, where the switching time between these two stages and the degree of variation depended oil the UV intensity and atmosphere. The decreasing stage was attributable to the photocaralytic decomposition of organic compound adsorbed onto the Surface, whereas the increasing stage was attributed to the capillary effect or an increase in the adsorbed water layer. Results demonstrated that UV intensity and atmosphere controlled the friction force. (C) 2009 Elsevier B.V. All lights reserved.

DOI： 10.1016/j.jphotochem.2009.01.009

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Low temperature preparation and machinability of porous ceramics from talc and foamed glass particles

Kiyoshi Okada, Fumihiko Ikawa, Toshihiro Isobe, Yoshikazu Kameshima, Akira Nakajima

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 29 ( 6 ) 1047 - 1052 2009年4月

記述言語：英語出版者・発行元：ELSEVIER SCI LTD

Porous ceramics were prepared by firing mixtures of talc (Mg(3)Si(4)O(10)(OH)(2)) and foamed glass particles (ceramic balloons, CB) with and without LiCl as a sintering acid. The mixing ratios of the starting materials were talc:CB = 7:3, 8:2, 9:1 and 10:0, with additions of LiCl of 0, 2 and 5 mass%. The mixtures were formed into pellets and fired at 600-1000 degrees C. The pellets without LiCl showed very poor strength even when fired at 1000 degrees C but those containing LiCl were much stronger, even when fired at only 600 degrees C. The crystalline phases in these samples changed to enstatite (MgSiO(3)) at >= 700 degrees C by decomposition of the talc under the fluxing action of the LiCl. The resulting samples were machinable and easily cut and drilled. The cutting rate decreased with increasing bending strength, for example, from 105 mm(2)/s and 6.3 MPa to 50 mm(2)/s and 16.3 MPa, respectively. The drilling rate of the present sample was found to be only slightly less than Teflon (polytetrafluoroethylene, PTFE) but much faster than graphite, glass ceramics, etc. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jeurceramsoc.2008.07.055

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Bioactivity and mechanical properties of CaSiO3/high-density polyethylene (HDPE) composites prepared by a new surface loading method of CaSiO3 powder

Kiyoshi Okada, Miho Tanuma, Yoshikazu Kameshima, Akira Nakajima, Shigeo Asai, Masao Sumita

MATERIALS RESEARCH BULLETIN 44 ( 2 ) 298 - 305 2009年2月

記述言語：英語出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

CaSiO3/high-density polyethylene (HDPE) composites with flexibility and biocompatibility were prepared by a new surface loading method. CaSiO3 powder was synthesized by coprecipitation method with heating at 1300 degrees C for 2 h. The obtained alpha-CaSiO3 powder was sieved to 45-75 mu m (sample M) and 75-150 mu m (sample C). Fine powder sample (sample F) was prepared by grinding the powder being the average particle size of 2.9 mu m. These powders were sprinkled on the melted HDPE sheets heated at 160, 180 and 200 degrees C. The amounts of sprinkled powder were only <0.1 vol.% but the ratios of surface coverage area were >50% in all the samples. Apatite formation in simulated body fluid (SBF) was observed by soaking for 5 days in sample F while within 1 day in samples M and C. The sample M retained flexible properties of HDPE together with excellent biocompatible properties. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.materresbull.2008.06.011

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