研究者詳細 - 亀島　欣一

MISC - 亀島　欣一

分割表示 97 件中 41 - 60 件目／全件表示 >>

Preparation and properties of titania-Cs2.5H0.5PW12O40 hybrid films

Akira Nakajima, Shunsuke Matsui, Sayaka Yanagida, Yoshikazu Kameshima, Kiyoshi Okada

SURFACE & COATINGS TECHNOLOGY 203 ( 9 ) 1133 - 1137 2009年1月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE SA

Using continuous coating with Si-alkoxide as a binder, Cs2.5H0.5PW12O40 (Cs2.5) powder was prepared and immobilized onto a Pyrex glass plate. The Cs2.5 coating possessed an acid site on the film surface. Translucent TiO2-Cs2.5 hybrid films were prepared by laminating TiO2 films with holes on the Cs2.5 coating using phase-separation of alkoxide. Photocatalytic decomposition of 1,4-dioxane in water revealed that the holes serve as adsorption fields for ethylene glycol diformate, an intermediate with poor affinity to TiO2. The TiO2-Cs2.5 hybrid films produced by this process are candidates for purification of water containing several chemicals with a slow decomposition rate in photocatalysis. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.surfcoat.2008.10.010

Web of Science

researchmap

Effect of Surface Structure on the Sustainability of an Air Layer on Superhydrophobic Coatings in a Water-Ethanol Mixture

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

LANGMUIR 25 ( 1 ) 13 - 16 2009年1月

記述言語：英語出版者・発行元：AMER CHEMICAL SOC

Using a laser beam and its reflection, we evaluated surface air layers on two superhydrophobic coatings with different roughnesses (R(a) = 1900 and 74 nm) in a water-ethanol mixture. The reflected laser intensity decreased by increasing the ethanol concentration for the superhydrophobic coating with large roughness because of increased scattering by the surface structure of the solid. However, it was almost constant and slightly increased for the coating with small roughness, probably because the liquid-air interface becomes flatter as the liquid intrudes into the surface structure. Results demonstrated that the difference in surface structure provides different sustainability of the surface air layer.

DOI： 10.1021/la802763h

Web of Science

researchmap

Photocatalytic destruction of 1,4-dioxane in aqueous system by surface-roughened tio2 coating on stainless mesh

Sayaka Yanagida, Akira Nakajima, Yoshikazu Kameshima, Kiyoshi Okada

Key Engineering Materials 412 137 - 141 2009年

記述言語：英語

This study investigated the effect of surface roughness on a coating of TiO2 submicron powders that had been applied on a stainless steel mesh using electrophoretic deposition (EPD). Roughness was provided to the surface of EPD coating using UV pre-illumination to the suspension prepared by isopropyl alcohol and commercial TiO2 powder. The Ra value was increased around 20% by this treatment. The rough coating provided a higher photocatalytic decomposition rate of 1,4-dioxane in water than a smooth coating obtained from the suspension without UV pre-illumination. That increase is attributable to the increase of the reaction field on the coating surface.

DOI： 10.4028/www.scientific.net/KEM.412.137

Scopus

researchmap

Photocatalytic destruction of 1,4-dioxane in aqueous system by surface-roughened TiO(2) coating on stainless mesh

Sayaka Yanagida, Akira Nakajima, Yoshikazu Kameshima, Kiyoshi Okada

ELECTROPHORETIC DEPOSITION: FUNDAMENTALS AND APPLICATIONS III 412 137 - 141 2009年

記述言語：英語出版者・発行元：TRANS TECH PUBLICATIONS LTD

This study investigated the effect of surface roughness on a coating of TiO(2) submicron powders that had been applied on a stainless steel mesh using electrophoretic deposition (EPD). Roughness was provided to the surface of EPD coating using UV pre-illumination to the suspension prepared by isopropyl alcohol and commercial TiO(2) powder. The R(a) value was increased around 20% by this treatment. The rough coating provided a higher photocatalytic decomposition rate of 1,4-dioxane in water than a smooth coating obtained from the suspension without UV pre-illumination. That increase is attributable to the increase of the reaction field on the coating surface.

DOI： 10.4028/www.scientific.net/KEM.412.137

Web of Science

researchmap

Preparation and electrochemical property of manganese oxide/carbon composites

Y. Kameshima, H. Wagata, A. Nakajima, K. Okada

Journal of Physics: Conference Series 191 12015 2009年

記述言語：英語出版者・発行元：Institute of Physics Publishing

A novel electro-chemical capacitor was tried to synthesis by assemble carbon powder with manganese oxide using an ultra-sonication in KMnO4 solution. (ultrasonic sample). A reference sample was prepared by same condition except for radiation of ultra-sonication (settle sample). Both ultrasonic sample and settle sample show the composite of manganese oxide and carbon. Additionally, layered manganese oxide phase was observed in the ultrasonic samples. Surface atomic ratio of Mn/C decreased corresponding with increasing of used solution volume from 25 ml to 250 ml. The composite prepared using 100ml solution was greatly affected by the ultra-sonication. On the other hand, the amount of manganese on the surface has increased with the increasing of the irradiation of energy among the ultrasonic sample. The amount of manganese deposition was almost saturated with 100 mW/cm3. Cyclic voltammetry curves of the obtained composites were influenced by scanning speed. The ultrasonic sample shows higher electrical capacitance than the settle sample in various conditions. © 2009 IOP Publishing Ltd.

DOI： 10.1088/1742-6596/191/1/012015

Scopus

researchmap

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

Y. Kameshima, A. Nakajima, K. Okada, T. Yano

J. Ceram. Soc. Jpn. 117 ( 1371 ) 1229 - 1232 2009年

P57 多孔性を利用したメソポーラスシリカ/チタニア複合体の作製(ポスター討論)

吉澤章博, 磯部敏宏, 亀島欣一, 中島章, 岡田清

粘土科学討論会講演要旨集 ( 52 ) 270 - 271 2008年9月

B17 タルクを用いたマシナブルセラミックスの作製(口頭発表,一般講演)

岡田清, 井川史彦, 磯部敏宏, 亀島欣一, 中島章

粘土科学討論会講演要旨集 ( 52 ) 118 - 119 2008年9月

P23 ケイ皮酸ナトリウム/層状複水酸化物複合体の作製と紫外線照射の影響(ポスター討論)

中田綾, 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 ( 52 ) 202 - 203 2008年9月

A13 テトラクロロ白金酸/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, 中島章, 岡田清

粘土科学討論会講演要旨集 ( 52 ) 56 - 57 2008年9月

P58 多孔性ジオポリマーの作製とその保水特性の評価(ポスター討論)

大山朝美, 磯部敏宏, 亀島欣一, 中島章, 岡田清

粘土科学討論会講演要旨集 ( 52 ) 272 - 273 2008年9月

Preparation of barium titanate nanoparticle sphere arrays and their dielectric properties

Satoshi Wada, Aki Yazawa, Takuya Hoshina, Yoshikazu Kameshima, Hirofumi Kakemoto, Takaaki Tsurumi, Yoshihiro Kuroiwa

IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL 55 ( 9 ) 1895 - 1899 2008年9月

記述言語：英語出版者・発行元：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Barium titanate (BaTiO3) nanoparticles from 27 to 192 nm were prepared by the 2-step thermal decomposition method from barium titanyl oxalate nanoparticles. These particles were dispersed well into 1-propanol, and dense BaTiO3 nanoparticle sphere arrays without stress-field were prepared by the meniscus method. Temperature dependence of dielectric properties was successfully measured using these dense nanoparticle sphere arrays, and size effect on dielectric properties was discussed.

DOI： 10.1109/TUFFC.880

Web of Science

researchmap

Effect of the crystallinity of kaolinite precursors on the properties of mesoporous silicas

Myoshi Okada, Hisako Yoshizaki, Yoshikazu Kameshima, Akira Nakajima

APPLIED CLAY SCIENCE 41 ( 1-2 ) 10 - 16 2008年9月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

Mesoporous silicas (MesoPSs) were hydrothermally synthesized from calcined and selectively acid-leached kaolinites with a range of crystallinity, using cetyltrimethyl ammonium bromide (CTABr), to investigate the effect of the kaolinite crystallinity on the porous properties of the resulting MesoPSs. Four kaolinites were used, with Hinckley indices ranging from 0.51 to 1.20 and (001) crystallite sizes ranging from 20 to 37 nm. After calcination at 600 degrees C for 24 h they were selectively leached with 2.5 M H(2)SO(4) at 90 degrees C for 2 h to prepare microporous silica (MicroPSs). The Si/Al ratios of these MicroPSs varied from 21 to 82 and their specific surface areas (S(BET)) ranged from 169 to 370 m(2)/g, these parameters tending to increase with decreasing Hinckley index of the kaolinite. MesoPSs were synthesized by reacting the resulting MicroPSs with CTABr in NaOH solution under hydrothermal conditions. The MicroPS was mixed with CTABr, NaOH and water in the molar ratio (MicroPS):CTABr:NaOH:H(2)O = 1:0.1:0.3:150. The synthesis was carried out by stirring the suspension at room temperature for 24 h, aging for 24 h, hydrothermal treatment at 110 degrees C for 24 h and calcination at 560 degrees C for 6 h to remove the surfactants. The S(BET) values of the resulting MesoPSs ranged from 932 to 1240 m(2)/g, correlating with the S(BET) values of the precursor MicroPS and the crystallinity of the kaolinite starting materials. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.clay.2007.09.009

Web of Science

researchmap

Utilization of steel-making slag for the uptake of ammonium and phosphate ions from aqueous solution

Vinay Kumar Jha, Yoshikazu Kameshima, Akira Nakajima, Kiyoshi Okada

JOURNAL OF HAZARDOUS MATERIALS 156 ( 1-3 ) 156 - 162 2008年8月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

Steel-making slag, a waste by-product of the Steel Industry, constitutes a major disposal problem. In the present study, excellent adsorbent materials for reducing eutrophication in wastewaters have been prepared from this slag. Heated samples of acid-treated slag and mixtures of slag with kaolinite and Al(OH)(3) were examined to determine their uptake capacities for NH4+ and PO43- from aqueous solutions. In general, the equilibrium pH of the solution increased in comparison to initial pH with the uptake of target ions, the sample activated slag-Al(OH)(3) showing the smallest change. The highest PO43- uptake capacity was obtained with the slag-Al(OH)(3) mixture heated at 900 degrees C whereas the highest uptake of NH4+ was found in the slag-Al(OH)(3) mixture heated at 800 degrees C. The uptake rates for PO43- and NH4+ by the slag-Al(OH)(3) mixture heated at 900 degrees C were 2.91 and 0.65 mu mol/(g min), respectively. It was shown that heating slag composites prior to incorporation into wastewater treatment filters resulted in an increased degree of NH4+ and PO43- uptake. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2007.12.009

Web of Science

researchmap

Processing and properties of transparent sulfated TiO(2) thin films using sol-gel method

Akira Nakajima, Aiko Nakamura, Naoki Arimitsu, Yoshikazu Kameshima, Kiyoshi Okada

THIN SOLID FILMS 516 ( 18 ) 6392 - 6397 2008年7月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE SA

For this study, transparent sulfated TiO(2) thin films were prepared from Ti alkoxide. Vacuum ultraviolet illumination in air at 180 degrees C was demonstrated to be an effective pretreatment for reproducible preparation of crack-free sulfated TiO(2) thin films. The film provides a high photoinduced wettability conversion rate and photocatalytic decomposition efficiency on gaseous n-hexane under proper conditions. This result is attributable to the accelerated decomposition of intermediates by a strong inorganic acid on the surface or to the resultant high quantum yield by suppressing the recombination between electrons and holes on the film surface. (c) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.tsf.2007.12.161

Web of Science

researchmap

Effect of liquid viscosity on the internal fluidity of a droplet sliding on a fluoroalkylsilane coating

Yuu Sakurada, Shunsuke Suzuki, Munetoshi Sakai, Akira Nakajima, Yoshikazu Kameshima, Kiyoshi Okada

CHEMISTRY LETTERS 37 ( 7 ) 688 - 689 2008年7月

記述言語：英語出版者・発行元：CHEMICAL SOC JAPAN

The effect of liquid viscosity on the internal fluidity of droplets during sliding on an inclined Si surface treated with fluoroalkylsilane (FAS) was investigated for water-glycerin mixture using particle image velocimetry (PIV). Increasing viscosity remarkably decreases the slipping motion on the solid-liquid interface and overall sliding acceleration. It affects the rolling motion, but its degree of influence is smaller than that on slipping. The viscosity had different contributions to slipping and rolling motions of the droplets.

DOI： 10.1246/cl.2008.688

Web of Science

researchmap

Processing and photocatalytic properties of transparent 12 tungsto(VI) phosphoric acid - TiO(2) hybrid films

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

CHEMISTRY OF MATERIALS 20 ( 11 ) 3757 - 3764 2008年6月

記述言語：英語出版者・発行元：AMER CHEMICAL SOC

Using the layer-by-layer method, 12 tungsto(VI) phosphoric acid (PW(12)) and TiO(2) hybrid thin films were prepared. In 2-propanol decomposition, two-bilayer thin films (ca. 15 nm) showed more rapid decomposition than control TiO(2) and PW(12) films under both UV and Visible light illumination. Visible light illumination was required for continuous 2-propanol decomposition. Photocatalytic decomposition activity depends on the number of bilayer coatings, the top coating, and the organic compounds for decomposition. On the basis of the wavelength dependence of the hybrid thin films, a reaction scheme for this system was discussed.

DOI： 10.1021/cm800167x

Web of Science

researchmap

Effect of atmosphere on photo-induced friction force variation on (001) rutile

Akira Nakajima, Aya Nakada, Naoki Arimitsu, Yoshikazu Kameshima, Kiyoshi Okada

MATERIALS LETTERS 62 ( 8-9 ) 1319 - 1321 2008年3月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

Variations of friction force and surface potential were evaluated using friction force microscopy (FFM) and Kelvin force microscopy (KFM) on (100) and (001) faces of rutile single crystals under UV illumination in three different atmospheres: dry nitrogen, dry air, and ambient air. Friction force and surface roughness for the (100) face did not exhibit remarkable dependence on either UV illumination or on the atmosphere. However, the friction force of the (001) face increased by UV illumination in dry air without roughness variation. The surface potential of the (001) face changed negatively and more remarkably than that of the (100) face by UV illumination. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.matlet.2007.08.036

Web of Science

researchmap

Water-retention properties of porous ceramics prepared from mixtures of allophane and vermiculite for materials to counteract heat island effects

Kiyoshi Okada, Shunsuke Matsui, Toshihiro Isobe, Yoshikazu Kameshima, Akira Nakajima

CERAMICS INTERNATIONAL 34 ( 2 ) 345 - 350 2008年3月

記述言語：英語出版者・発行元：ELSEVIER SCI LTD

Porous ceramics for anti-heat island effect were prepared from mixtures of allophane and vermiculite (VA samples). Allophane and vermiculite which had been ground for 0.5-2 h was mixed in various mass ratios, formed into pellets by uniaxial pressing at 40 MPa, and heated at 600-800 degrees C to form porous ceramics. The large thermal expansion of the vermiculite upon explosive dehydration of interlayer water causes cracking of the pellets with higher vermiculite contents. However, this can be controlled by grinding the vermiculite prior to heating. Grinding the vermiculite for >= 2 It suppresses its expansion, enabling pellet samples with high vermiculite contents to be prepared without cracking. The bulk densities of samples prepared at 800 degrees C from vermiculite ground for 2 h decrease from 1.72 to 0.94 with increasing allophane content. The pore size distribution in these samples shows a distinct peak at about 1 mu m irrespective of the mixing ratio. The number of smaller pores (50 nm) increases with increasing allophane content while the number of larger pores (20-40 mu m) increases with increasing vermiculite content. The compressive strengths of the samples range from I to 3 MPa except for samples containing a high proportion of vermiculite ground for I h. The water absorption (W-a) of the samples increases from 37 to 63% with increasing allophane content. This absorption rate is fast enough to absorb >90% of the W-a within 1 min for samples of 10 mm phi x 5 mm(3) size. By contrast, the release of the absorbed water is very slow, with 50% of the W-a retained for >= 30 h in the VA samples at a relative humidity of 55% at 20 degrees C this is slower than in pure allophane and much slower than in a reference sample of foamed glass (about 4 h). All these properties make the VA samples useful as water-retaining materials to combat "heat island" effects. (c) 2006 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

DOI： 10.1016/j.ceramint.2006.10.006

Web of Science

researchmap

Preparation and sorption properties of materials from paper sludge

M. Hojamberdiev, Y. Kameshima, A. Nakajima, K. Okada, Z. Kadirova

JOURNAL OF HAZARDOUS MATERIALS 151 ( 2-3 ) 710 - 719 2008年3月

記述言語：英語出版者・発行元：ELSEVIER SCIENCE BV

Three materials were prepared from paper sludge (PS) using different treatment processes and their sorption abilities for phosphate and methylene blue (MB) were determined. The samples were a powder sample prepared by heating PS in air (sample C), a pellet prepared by grinding, forming and heating PS in air (sample G) and a powder prepared by physical activation of PS in flowing wet nitrogen (sample A). The three samples were heated at 600-900 degrees C for 6h. On heating at 700-800 degrees C, the organic fibers, limestone (CaCO3) kaolinite (Al2Si2O5(OH)(4)) and talc (Mg3Si4O10(OH)(2)) in the original PS were converted to amorphous CaO-Al2O3-SiO2 (CAS) and talc in sample C, while CAS was formed in sample G and activated carbon, CAS and talc was formed in sample A. On heating at 900 degrees C the CAS converted to gehlenite (Ca2Al2SiO7) and anorthite (CaAl2Si2O8). The specific surface areas (SBET) of the three samples achieved maximum values of 23, 37 and 70 m(2)/g upon heating at 700, 600 and 600 degrees C, respectively. The SBET value of the activated sample A was distinctly lower than usually reported for activated carbon. The samples C, G and A achieved maximum phosphate sorption capacities of 2.04, 1.38 and 1.70 mmol/g, calculated from the Langmuir model, upon heating at 700, 700 and 800 C, respectively. The maximum sorption capacity for phosphate in sample C is attributed to the sorption by CAS, namely, adsorption on the alumina component and precipitation as Ca-phosphates. The MB multifunctional sorption capacity of sample A was 0.11 mmol/g. The phosphate and MB sorption rates show better correlation with a pseudo-second order model than with other models. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2007.06.058

Web of Science

researchmap

　前のページ - 次のページ　

<亀島 欣一>

MISC - 亀島 欣一

<亀島　欣一>

MISC - 亀島　欣一