OHYA Yutaka

J-GLOBAL         Last updated: Jul 23, 2019 at 08:51
 
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Name
OHYA Yutaka
Affiliation
Gifu University
Section
Faculty of Engineering
Degree
Doctor of Engineering(Tokyo Institute of Technology)
ORCID ID
0000-0001-5271-3641

Research Interests

 
 

Research Areas

 
 

Academic & Professional Experience

 
1991
 - 
2003
Professor, Faculty of Engineering, Gifu University
 
1983
 - 
1991
Tokyo Institute of Technology,
 
1990
   
 
- Max-Planck Institute,(Germany)
 
 
   
 
Post・Doctoral Feller
 
 
   
 
Research Assistant
 

Education

 
 
 - 
1983
Graduate School, Division of Integrated Science and Engineering, Tokyo Institute of Technology
 
 
 - 
1980
Faculty of Engineering, Tokyo Institute of Technology
 

Published Papers

 
Labanni Arniati, Zulhadjri Zulhadjri, Handayani Dian, Ohya Yutaka, Arief Syukri
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY      Jun 2019   [Refereed]
Moriyama Takahiro, Hayashi Kensuke, Yamada Keisuke, Shima Mutsuhiro, Ohya Yutaka, Ono Teruo
PHYSICAL REVIEW MATERIALS   3(5)    May 2019   [Refereed]
Yamada Tsuyoshi, Masuda Hayato, Park Kwihwan, Tachikawa Takumu, Ito Naoya, Ichikawa Tomohiro, Yoshimura Masatoshi, Takagi Yukio, Sawama Yoshinari, Ohya Yutaka, Sajiki Hironao
CATALYSTS   9(5)    May 2019   [Refereed]
Takayuki Ban, Shota Iriyama, Yutaka Ohya
Advanced Powder Technology   29(3) 537-542   Mar 2018   [Refereed]
? 2017 The Society of Powder Technology Japan Hydrothermal treatment of aqueous mixtures of boehmite (AlOOH), phosphoric acid, and tetramethylammonium hydroxide provided two types of layered aluminophosphates having tetramethylammonium ion (TMA+) ...
Takayuki Ban, Takahiro Wakita, Ryo Yokoyama, Tatsuya Miyake, Yutaka Ohya
CrystEngComm   20(25) 3559-3568   Jan 2018   [Refereed]
? The Royal Society of Chemistry 2018. The influence of the negative charge densities of metalate nanosheets on their bottom-up syntheses was examined. Metalate nanosheets are usually prepared by exfoliating layered metalates. For each metalate, t...
Yutaka Ohya, Yukihiro Kawauchi, Takayuki Ban
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   125(9) 695-700   Sep 2017   [Refereed]
? 2017 The Ceramic Society of Japan. All rights reserved. Pseudobrookite-type titanate has two types of oxide octahedra for different cation types. The cation distributions in the octahedra of three pseudobrookite type oxides, Al 2 TiO 5 , MgTi 2 ...
Kyyoul Yun, Shunji Yanase, Takayuki Ban, Yutaka Ohya
IEEE Transactions on Magnetics   53(12)    Jun 2017   [Refereed]
IEEE In this paper, we propose a new metal bonding method using a ceramic precursor (zirconium butoxide or titanium tetraisopropoxide) or a ceramic nano powder. Magnetic hysteresis curves of the bonded specimen did not change significantly after b...
Syukri Arief, Putri Hidayani, Lusi Aferta, Zulhadjri, Takayuki Ban, Yutaka Ohya
Oriental Journal of Chemistry   33 87-91   Jan 2017   [Refereed]
? 2017, Oriental Scientific Publishing Company. All rights reserved. Several bioreduction processes become appreciation for the synthesis of silver nanoparticles (AgNPs) because of their multiple applications, cost effective and eco-friendly. The ...
Yutaka Ohya, Shu Yamamoto, Shu Yamamoto, Takayuki Ban, Makoto Tanaka, Satoshi Kitaoka
Journal of the European Ceramic Society   37(4) 1673-1680   Apr 2017   [Refereed]
? 2016 Elsevier Ltd.To fabricate aluminum titanate ceramics that possess both low thermal expansion coefficients and excellent mechanical properties, the co-doping of MgO with Y2O3, La2O3 and Nb2O5 was examined. Doping with MgO lowered the formati...
Takayuki Ban, Yasuhiko Kondo, Yutaka Ohya
CrystEngComm   18(45) 8731-8738   Jan 2016   [Refereed]
? 2016 The Royal Society of Chemistry. The bottom-up synthesis of titanate nanoflakes in ionic liquid solvents was carried out by heating mixtures of titanium isopropoxide (TIP), 40% tetrabutylammonium hydroxide (TBAOH) aqueous solution, and ionic...
New fabrication method suggestion of the motor core using ceramic precursor
Kyyoul Yun, Masaki Hirano, Shunji Yanase and Yutaka Ohya
Int. J. Metall. Mater. Sci. Eng.   6 1-8   2016   [Refereed]
Takayuki Ban, Takuya Nakagawa, Yutaka Ohya
Crystal Growth and Design   15(4) 1801-1807   Apr 2015   [Refereed]
? 2015 American Chemical Society. The size, shape, and stacking of titanate nanosheets synthesized by heating aqueous mixtures of titanium complexes and tetrabutylammonium hydroxide were dependent on the type and amount of organic ligands and the ...
Syukri Arief, Vivi Gustia, Diana Vanda Wellia, Zulhadjri, Takayuki Ban, Yutaka Ohya
Journal of Chemical and Pharmaceutical Research   7(9S) 189-192   Jan 2015   [Refereed]
? 2015, Journal of Chemical and Pharmaceutical Research. All rights reserved.Synthesis of silver nanoparticle using Gambier leaves (Uncaria gambier Roxb) extract and diethanol amine (DEA) as stabilizer has been done successfully. Synthesis process...
Sher Alam, Chokkalingam Anand, Chokkalingam Anand, Kripal Singh Lakhi, Jin Ho Choy, Wang Soo Cha, Wang Soo Cha, Ahmed Elzhatry, Salem S. Al-deyab, Yutaka Ohya, Ajayan Vinu
ChemPhysChem   15(16) 3440-3443   Aug 2014   [Refereed]
The preparation of size-controllable Fe2O3 nanoparticles grown in nanoporous carbon with tuneable pore diameters is reported. These hybrid materials exhibit strong non-linear magnetic properties and a magnetic moment of approximately 229emug-1, wh...
Takayuki Ban, Shota Oishi, Yutaka Ohya
Journal of Porous Materials   21(3) 337-344   Jan 2014   [Refereed]
Silicalite-1 crystals were hydrothermally synthesized from silica gels prepared under different conditions. The influence of the state of Si species in the silica gels and the concentrations of silicate ions and a template agent in the reaction so...
YAMAMOTO Syu, SOGA Takuya, BAN Takayuki, OHYA Yutaka, KITAOKA Satoshi
耐火物 = Refractories   62(3)    Mar 2010
Yutaka Ohya, Jyunya Okano, Yuki Kasuya, Takayuki Ban
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   117(9) 973-977   Sep 2009   [Refereed]
Ga2O3 thin films were fabricated using the Ga nitrate and GaOOH aqueous solutions. The films were crystallized as β-Ga 2O3phase by heating at 700°C and the band gap of resultant films was about 4.9 eV. The films were uniform and the film from Ga n...
Takayuki Ban, Tomohiko Nakatani, Yutaka Ohya
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   117(1363) 268-272   Mar 2009   [Refereed]
Anatase was hydrothermally synthesized from transparent aqueous sols including layered titanate colloids. The reaction sols were prepared from titanium isopropoxide and different alkylammonium hydroxides (NR 4OH). The influence of the type of NR 4...
Shigeyuki Uemiya, Atsushi Tanigawa, Tatsuya Koike, Yukichi Sasaki, Takayuki Ban, Yutaka Ohya, Ryo Yoshiie, Makoto Nishimura, Naoki Yamamoto, Katsunori Yogo, Koichi Yamada
Journal of Porous Materials   15(4) 405-410   Aug 2008   [Refereed]
Oriented ZSM-5 seed crystals on an α-Al2O3 porous substrate were hydrothermally treated in a raw sol. The ZSM-5 membranes were fabricated via secondary growth of the seed crystals. For some samples, the seed-applied substrate was fired at 300 or 6...
Shigeo Hayashi, Takashi Sato, Yutaka Ohya, Zenbe E. Nakagawa
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   116(6) 786-791   Jul 2008   [Refereed]
Authors have been trying to fabricate cristobalite-containing mullite bodies with high strength and toughness by reheating mullite-glass sintered bodies. In this process, a phenomenon that once-crystallized cristobalite layer changed back to amorp...
Takayuki Ban, Junichi Morimoto, Yutaka Ohya
Materials Chemistry and Physics   109(2-3) 347-351   Jun 2008   [Refereed]
Zeolite L thin films were fabricated by applying fine zeolite L seed crystals on glass substrates and then hydrothermally treating the seeded substrates in reaction sols. The influence of anisotropic growth of the seed crystals on the orientation ...
Fumihito Ogawa, Takayuki Ban, Yutaka Ohya
Thin Solid Films   516(15) 4863-4867   Jun 2008   [Refereed]
Hybrid inorganic-organic films were fabricated from aqueous colloidal solutions of a layered titanate salt and cationic and anionic surfactants. Cetyltrimethylammonium bromide and dodecyl phosphate were used as cationic and anionic surfactants, re...
Takayuki Ban, Tomohiko Nakatani, Yasufumi Uehara, Yutaka Ohya
Crystal Growth and Design   8(3) 935-940   Mar 2008   [Refereed]
Six-pointed starlike anatase aggregates were synthesized hydrothermally from aqueous sols of tetramethylammonium titanate colloids having a lepidocrocite-type layered structure. Their microstructure was examined by transmission electron microscopy...
Yutaka Ohya, Yutaka Ohya, Tomonori Yamamoto, Takayuki Ban, Takayuki Ban
Journal of the American Ceramic Society   91(1) 240-245   Jan 2008   [Refereed]
The dependence of the electrical conductivity of pure (99.999%) and tin-doped indium oxide (In2O3) ceramics on oxygen partial pressure was investigated at 800° and 850°C. The doping amount of tin was 100-1000 ppm, which is within the solubility li...
Takayuki Ban, Tomoyuki Sakai, Yutaka Ohya
Crystal Research and Technology   42(9) 849-855   Sep 2007   [Refereed]
ZnO crystals were synthesized from basic aqueous solutions including zincate ions stabilized with triethanolamine (N(C2H 4OH)3, teaH3) by heating at 60°C. The influence of the basicity of the solutions on the morphology of the ZnO crystals was exa...
Takayuki Ban, Haruka Saito, Miyoshi Naito, Yutaka Ohya, Yasutaka Takahashi
Journal of Porous Materials   14(2) 119-126   Jun 2007   [Refereed]
Zeolite L crystals were synthesized hydrothermally from aqueous mixtures of potassium hydroxide, metallic aluminum, and colloidal silica. The influence of hydrothermal conditions and the addition of triethanolamine (N(C 2H4OH)3; H3tea) upon the fo...
Yutaka Ohya, Yuki Yahata, Takayuki Ban
Journal of Sol-Gel Science and Technology   42(3) 397-405   Jun 2007   [Refereed]
PZT films with different microstructure and Zr:Ti ratios were fabricated on ITO/glass and platinized silicon wafer substrates by dip-coating. A dense film of 2% porosity and a porous film of 19% porosity were obtained by repetition of thin and thi...
Yasuo Okazaki, Ma Lixin, Yutaka Ohya, Shunji Yanase, Shuichiro Hashi
Journal of Materials Processing Technology   181(1-3) 66-70   Jan 2007   [Refereed]
TixCo1+xFe2-2xO4 (0 ≦ x ≦ 0.5) ferrite films and its composite films with CoFe2O4 synthesized by a sol-gel method were investigated on crystallographic and magnetic properties. Magnetization decreased with the increase of Ti content while coercive...
Yutaka Ohya, Hiroki Ishikawa, Takayuki Ban
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   114(1329) 411-414   May 2006   [Refereed]
Zirconium oxide thin films were fabricated using a sol-gel method. The sols were prepared using zirconium alkoxide and acetate. An alcoholic solution of the alkoxide and an aqueous solution of the acetate were dip-coated on a glass substrate and f...
SATO Takashi, SAWABE Yoshinari, OHYA Yutaka, HAYASHI Shigeo, NAKAGAWA Zenbe-e
耐火物   58(3)    Mar 2006   [Refereed]
Hitoshi Ohashi, Yasuo Okazaki, Yutaka Ohya, Shunji Yanase, Shuichiro Hashi
IEEE Transactions on Magnetics   42(10) 2891-2893   Jan 2006   [Refereed]
Magnetic properties related to nano-structure have been investigated for sol-gel grown spinel Co-ferrite thin films of which thickness was 200?300 nm controlled by spin coating. The magnetic properties depended on the annealing temperature, and th...
Improvement of NO2 Gas Selectivity of Sol-Gel SnO2 Thin Film Sensor by Doping with Transition Metal Ions
Ohya Y.(Gifu Univ.),Sakakibara K.(Gifu Univ.),Ban T.(Gifu Univ.)
Proc. 22nd International Japan-Korea Seminar on Ceramics   24-26 507-511   2005   [Refereed]
Preparation of Oriented PZT Films via Sol-Gel Method and Their Dielectric and Piezoelectric Properties
Y. Ohya, T. Tamakoshi, T. Ban and Y. Takahashi
Trans. Mater. Res. Soc. Jpn.   29(4) 1139-1142   2004   [Refereed]
Yutaka Ohya, Zenbe E. Nakagawa, Kenya Hamano, Hiroshi Kawamoto, Satoshi Kitaoka
Mat. Res. Soc. Symp. Proc   658(GG3.17.1-5) 1-5   Dec 2001   [Refereed]
A microstructural change during the formation reaction of aluminum titanate from a mixture of rutile and corundum powders has been studied. The characterization was carried out using a polarization microscope, a scanning electron microscope and a ...
Preparation of Concentrated, Halogen-Free Aqueous Titanium Solutions
T. Ohya, T. Ban, Y. Ohya and Y. Takahashi
Ceramic Processing Science VI, Ceramics Transactions Vol. 112,   112 47-52   2001   [Refereed]
Dip-Coating of Metal Films from Metal Acetates-Acetolhydrazone System
Syukri, T. Terazawa, T. Ban, Y. Ohya and Y. Takahashi
Ceramic Processing Science VI, Ceramics Transactions Vol. 112,   112 329-334   2001   [Refereed]
Yutaka OHYA, Tomokazu ITO, Masahiro KANEKO, Takayuki BAN, Yasutaka TAKAHASHI
J. Ceram. Soc. Jpn.   108(1261) 803-806   Dec 2000   [Refereed]
Solid solubility of SnO2 in In2O3 was investigated in the interval between 1000 to 1500°C. Samples were prepared using In2O3 powder and tin alkoxide solution, as well as mixed solution of indium and tin alkoxides. X-ray diffraction analysis reveal...
Takashi Sato, Yoshinari S A Wabe, Yutaka Ohya, Mikio Sugai, Zenbe E. Nakagawa
J. Ceram. Soc. Jpn.   108(1256) 345-349   Dec 2000   [Refereed]
Cracking of a cristobalite-containing mullite body at the middle stage of crystallization during cooling was investigated by acoustic emission (AE) and the crack formation was discussed. The specimen was composed of an outside layer of crystalline...
Gas Sensing Properties of Porous Insulator/Oxide Semiconductor Multi-layered Films
Y. Ohya, T. Manabe, A. Hirose, T. Ban and Y. Takahashi
Trans. Mater. Res. Soc. Jpn.   25(4) 1207-1210   2000   [Refereed]
Preparationof Mg-Al Spinel Powder from Nitrates Using Autoclaveat Low Temperature
Z. Nakagawa, K. Watanabe, Y. Ohya, and K. Hamano
Proc. Joint ISHR and ICSTR   (July 25-28) 453-456   2000   [Refereed]
Takashi Sato, Yoshinari Sawabe, Yutaka Ohya, Mikio Sugai, Zenbe E. Nakagawa
Journal of the Ceramic Society of Japan   107(9) 838-843   Dec 1999   [Refereed]
Crystallization of glass phase to cristobalite was investigated in mullite-glass ceramics with excess SiO 2 compositions (5.3-16.4 mass%), namely, higher than stoichiometric mullite. Starting powders were prepared by alkoxide hydrolysis method. Co...
Takayuki Ban, Takafumi Ohwaki, Yutaka Ohya, Yasutaka Takahashi
Angewandte Chemie - International Edition   38(22) 3324-3326   Nov 1999
Growth of oriented seed crystals on a substrate led to a completely oriented and continuous membrane of LTA-type zeolite. The seed crystals of cubic morphology were dip-coated onto a tilted substrate (see schematic diagram) with the zeolite channe...
Electrical Properties of ZrO2 Thin Films Doped with In2O3 by Sol-Gel Method
Y. Ohya, M. Murayama, and Y. Takahashi
Key Eng. Mater., 169-170, 175-178 (1999)   169 175-178   1999
V. Kumar, Y. Ohya, and Y. Takahashi
Jpn. J. Appl. Phys.   37(8) 4477-4481   Aug 1998   [Refereed]
Ferroelectric thin films of PbTiO3 and Pb(Zr0.5Ti0.5)O3 were deposited using a sol-gel process from a highly stable precursor solution derived from a unique and simple system consisting of basic lead acetate, titanium and zirconium butoxides. This...
Koichiro Hayashi, Masahiro Hosokawa, Tsukasa Yoshida, Yutaka Ohya, Yasutaka Takahashi, Osamu Yamamoto, Hideki Minoura
Materials Science and Engineering B   49 239-242   Oct 1997   [Refereed]
A composite film composed of strontium doped lanthanum manganite (SLM), La0.9Sr0.1MnO3 and yttria stabilized zirconia (YSZ), (ZrO2)0.96(Y2O3)0.04, has been successfully prepared by metal-organic decomposition (MOD) at temperatures of 800-1000°C us...
Gas Sensing Properties of SnO2 Thin Films Prepared from Aqueous Sol
大矢 豊, 三浦裕嗣, 伴 隆幸, 高橋康隆, 西垣 進, 岡本芳樹, 原田昭雄
Research Report, Center for Cooperative Research, Gifu University   7(7) 87-91   1997
La0.5Sr0.5MnO3-YSZ Composite Film Electrodes Prepared by Metal-organic Decomposition for SOFC
K. Hayashi, T. Yoshida, M. Hosokawa, Y. Ohya, Y. Takahashi, O. Yamamoto and H. Minoura
Elecrrochem. Soc. Proc.   97(24) 700-707   1997   [Refereed]
La1-xSrxMnO3-YSZ Composite Film Electrodes Prepared by Metal-organic Decomposition for Solid Oxide Fuel Cell
Hayashi K.(Gifu Univ.),Hosokawa M.(Gifu Univ.),Yoshida T.(Gifu Univ.),Ohya Y.(Gifu Univ.),Takahashi Y.(Gifu Univ.),Yamamoto O.(Gifu Univ.),Minoura H.(Gifu Univ.)
Mater. Sci. Eng.   B49 239-242   1997
Coating of Oxide Films on Metal Powder-Themal and Electrical Properties-
大矢 豊, 玉井一誠, 高橋康隆, 伴 隆幸, 西垣 進, 岡本芳樹, 原田昭雄
岐阜大学地域共同研究センター研究成果報告書   6 73-78   1996
Preparation of LiTaO3 Thin Film by Sol-Gel Method
Y. Ohya, Y. Ogawa, R. Ito, J. Oguri, T. Ban, S. Demachi, and Y. Takahashi
Trans. Mater. Res. Soc. Jpn.   20 632-635   1996
Electrical Conductivity of Mn-Doped Indium Oxide Thin Films in Moist Air
Y. Takahashi, R. Bel Hadj Tahar, K. Shimaoka, T. Ban and Y. Ohya
Trans. Mater. Res. Soc. Jpn.   20 538-541   1996
Masaaki Kanamori, Hideki Ohtake, Yutaka Ohya, Yasutaka Takahashi
Journal of the Ceramic Society of Japan. International ed.   103(1) 59-63   Jan 1995   [Refereed]
The effects of IV group element (Zr, Ti, Ge, Si) oxides addition on the grain growth of SnO2 thin films at elevated temperature (600°-1000°C) were investigated. It was found that addition of 10mol% GeO2 controlled the grain growth of SnO2 effectiv...
Coating of Oxide Films on Metal Powder-Morphology of Deposited Gels and Oxides on Silver Particle-
大矢 豊, 玉井一誠, 高橋康隆, 西垣 進, 岡部宏樹, 原田昭雄
岐阜大学地域共同研究センター研究成果報告書   5 61-66   1995
M. Kanamori, M. Takeuchi, Y. Ohya, and Y. Takahashi
Chem. Lett.   1994 2035-2038   1994   [Refereed]
Yutaka Ohya, Toshimasa Tanaka, Yasutaka Takahashi
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers   32(9B) 4163-4167   Sep 1993   [Refereed]
Lead zirconate titanate (PZT) films with the composition of Pb(ZrxTi1-x)O3(x: 0.2-0.8) were fabricated by dip-coating methods. The sol was prepared using ethanolamine as a sol stabilizer. The substrate was In2O3:Sn (ITO) sputtered glass (Corning #...
Application of Ethanolamine Method for the Preparation of Indium Oxide-Based Sols and Films
Y. Takahashi, H. Hayashi, and Y. Ohya
Mat. Res. Soc. Symp. Proc.   271 401-406   1993   [Refereed]
Yutaka Ohya, Yutaka Ohya, Michael J. Hoffmann, Michael J. Hoffmann, G?nter Petzow, G?nter Petzow
Journal of the American Ceramic Society   75(9) 2479-2483   Jan 1992   [Refereed]
TiB2-particle reinforcement is one of the most successful methods for improving the fracture toughness of SIC ceramics.1-3 Commercially available TiB2 powders, however, have a large particle size and/or are highly reactive so that they are not fav...
Application of Ethanolamine Method for the Preparation of Indium Oxide-Based Sols and Films
Mat. Res. Soc. Symp. Proc.   271 401-406   1992   [Refereed]
Corrosion of Various Materials by Molten Barium Nitrate
K. Takahashi, T. H. Sung, Y. Ohya, Z. Nakagawa, T. Nakamura
Report of Research Laboratory of Engineering Materials, Tokyo Institute of Ceramics   (16) 63-72   1991
スピネルの合成と焼結におけるふっ化物添加の影響
真保満雄, 中川善兵衛, 大矢 豊, 浜野健也
耐火物   42(9) 478-484   1990   [Refereed]
Shock Compaction of Diamond Powder in Reactive Mixtures
H. Kunishige, Y. Ohya, Y. Fukuyama, S. Watanabe, H. Tamura, A. B. Sawaoka, T. Taniguchi, and Y. Horie
Report of the Research Laboratory of Engineering Materials, Tokyo Institute of Technology   (15) 235-264   1990
Corrosion of Aluminum Titanate Ceramics in Molten Aluminum
Y. Ohya, H. Kobayashi, Y. Nozaki, M. Hasegawa, Z. Nakagawa, and K. Hamano
Report of the Research Laboratory of Engineering Materials, Tokyo Institute of Technology   (15) 67-74   1990
Preparation and Properties of MgO Powder from Mg(OH)2 with F- Addition
M. Shimbo, Y. Ohya, Z. Nakagawa and K. Hamano
Proceedings of MRS Int'l. Mtg. Adv. Mats.   3 217-223   1989   [Refereed]
Application of Ultrasonic Technique for the Preparation of Ceramics Powder
Tomomasa Y.(Tokyo Inst, Tech,),Enomoto N.(Tokyo Inst, Tech,),Ohya Y.(Tokyo Inst, Tech,),Nakagawa Z.(Tokyo Inst, Tech,)
Proceedings of MRS Int'l. Mtg. Adv. Mats.   13 107-114   1989
Tae Hyun Sung, Zenbe e. Nakagawa, Shigeru Arima, Yasuro Ikuma, Yutaka Ohya, Nobuo Ishizawa, Masahiro Yoshimura
Journal of the Ceramic Society of Japan   97(10) 1005-1008   1989   [Refereed]
"Mullite Ceramics Prepared by Spray-Drying of Solution"
Z. Nakagawa, H. Kawabe, Y. Ohya, M. Hasegawa, and K. Hamano
Report RLEMTIT   (14) 39-47   1989
Yutaka Ohya, Zenbe E. Nakagawa, Kenya Hamano
Journal of the American Ceramic Society   71(5) C232-C233   May 1988   [Refereed]
Bending strength and Young's modulus of aluminum titanate ceramics at room temperature to 1300 degree C were examined. Bending strength increased from 62 MPa at room temperature to 280 MPa at 1100 degree C. Young's modulus also increased, to 99 GP...
Effect of Al2TiO5 Decomposition on the Microstructure and Mechanical Properties of TiO2-Added Alumina Ceramics
C.S. Hwang, Z. Nakagawa, Y. Ohya, and K. Hamano
Proceedings of International Institute for the Science of Sintering (IISS) Symposium   1 369-374   1988
Effects of Composition on Sintering and Bending Strength of Spinel Ceramics
T. Kanai, Z. Nakagawa, Y. Ohya, M. Hasegawa and K. Hamano
Report of the Research Laboratory of Engineering Materials, Tokyo Institute of Technology   (13) 75-83   1988
Yutaka Ohya, Zenbe e. Nakagawa, Kenya Hamano
Journal of the American Ceramic Society   70(8) C184-C186   Aug 1987   [Refereed]
The relation between grain size and grain-boundary microcracking during cooling in aluminum titanate ceramics was studied. Microcracking temperature was determined by the measurement of thermal contraction and expansion, which was accompanied by a...
Effects of Some Additives on Microstructure and Mechanical Strength of Aluminum Titanate Ceramics
Y. Ohya, M. Hasegawa, Z. Nakagawa, and K. Hamano
Report of the Research Laboratory of Engineering Materials, Tokyo Institute of Technology   (12) 81-91   1987
Effect of TiO2 on Initial Sintering of Al2O3
C.S. Hwang, Z. Nakagawa, T.H. Sung, Y. Ohya, and K. Hamano
Report of the Research Laboratory of Engineering Materials, Tokyo Institute of Technology   (12) 93-102   1987
Crack Propagation Resistance of Aluminum Titanate Ceramics
K. Hamano, Y. Ohya, and Z. Nakagawa
Int. J. High Technology Ceramics   1(2) 129-137   1985   [Refereed]
Preparation of Porous Spinel Ceramics and Their Electrical Properties
K. Hamano, Z. Nakagawa, S. Enmei, Y. Ohya, and M. Hasegawa
Report of the Research Laboratory of Engineering Materials, Tokyo Institute of Technology   (10) 68-77   1985

Misc

 
Yutaka Ohya
Handbook of Sol-Gel Science and Technology: Processing, Characterization and Applications   155-180   Jul 2018
© Springer International Publishing AG, part of Springer Nature 2018. Salts of many cations that dissolve in water are used in the sol-gel process. Depending on the cation, the salts include halides, primarily chlorides. It is also possible to use...
Takayuki Ban, Toshihiro Ito, Yutaka Ohya
Journal of Sol-Gel Science and Technology   68 88-94   Oct 2013
Oriented monoclinic WO3 thin films were fabricated by sol-gel method using aqueous sols of colloidal layered tungstates. The colloidal tungstate sols were prepared by reacting different alkylamines with layered tungstic acid H2WO4 in water. With d...
Takayuki Ban, Toshihiro Ito, Yutaka Ohya
Inorganic Chemistry   52 10520-10524   Sep 2013
Aqueous sols of colloidal layered tetramethylammonium (TMA) tungstate nanocrystals were obtained by diluting an aqueous suspension of TMA polyoxotungstate precipitates. The slow evaporation of the colloidal-layered tungstate sols led to the deposi...
Mutsuhiro Shima, Kazuo Oguri, Yutaka Ohya, Manabu Gomi, Yumi H. Ikuhara, Yusuke Sasaki, Yukio Hishikawa, Kenji Kawabe
IEEE Transactions on Magnetics   49 4824-4826   Aug 2013
Magnetic nanoparticles consisted of nickel zinc ferrite (NZF) were chemically synthesized by co-precipitation and simultaneously coated onto carbon microcoils (CMC), and their structure and magnetic properties were investigated. The samples were p...
Satoshi Kusuda, Yuichirou Yasukawa, Hiroki Shibata, Tomomi Saito, Osamu Doi, Yutaka Ohya, Norio Yoshizaki
Zoological Science   30 366-374   May 2013
The eggshells of 56 chelonians were examined by electron microscopy and X-ray diffractometry. They were classified into six types in terms of the matrix structure of their calcareous layer; type I was composed of a thin calcareous layer with miner...
Takayuki Ban, Takuya Ogura, Yoshitaka Ohashi, Roto Himeno, Fumitaka Ohashi, Tetsuji Kume, Yutaka Ohya, Hironori Natsuhara, Tamio Iida, Hitoe Habuchi, Shuichi Nonomura
Journal of Materials Science   48 989-996   Feb 2013
Crystal structures of endohedrally Na-doped type II silicon clathrates with variable Na content were refined by Rietveld analysis. Type II Si clathrates have two types of cages: small and large. The large cages were preferentially occupied by Na a...
Takayuki Ban, Makoto Takamura, Manami Morikawa, Yutaka Ohya
Materials Chemistry and Physics   137 1067-1072   Jan 2013
Thin disc-like zeolite L crystals were hydrothermally synthesized in the presence of organic ligands, such as catechol and acetylacetone. Thus, zeolite L crystals with many channel entrances on the surface were obtained. Although it was speculated...
Takayuki Ban, Shogo Yoshikawa, Yutaka Ohya
CrystEngComm   14 7709-7714   Nov 2012
Colloidal suspensions of highly water-dispersible tantalate were prepared by the acid-base reaction of tetramethylammonium hydroxide (TMAOH) and tantalic acid, which was formed via the hydrolysis of tantalum ethoxide, in water at a molar ratio of ...
Sher Alam, Javed Ahmad, Yutaka Ohya, Dong Chungli, Chih Chin Hsu, Jyh Fu Lee, Shima Mutsuhiro, Kazuki Miki, Salem S. Al-Deyab, Jinghua Guo, Chikashi Nishimura
Journal of the Physical Society of Japan   81    Jul 2012
Recently, an interesting multiferroic system PbVO 3 [A. A. Belik et al.: Chem. Mater. 17 (2005) 269] has been successfully prepared using a high-pressure and high-temperature technique. The crystallographic features of PbVO 3 were reported. In thi...
Makoto Tanaka, Kazumi Kashiwagi, Naoki Kawashima, Satoshi Kitaoka, Osamu Sakurada, Yutaka Ohya
Corrosion Science   54 90-96   Jan 2012
The effect of grain boundary cracks on the corrosion behaviour of non-doped aluminium titanate (AT) ceramics was evaluated in a molten Al alloy containing a slight amount of Mg. The corrosion of AT ceramics, in which the AT grains decomposed and s...
Takayuki Ban, Shogo Yoshikawa, Yutaka Ohya
Journal of Colloid and Interface Science   364 85-91   Dec 2011
Transparent aqueous sols of colloidal tetramethylammonium niobate nanocrystals were synthesized by mixing tetramethylammonium hydroxide (TMAOH), niobium ethoxide, and water at TMAOH/Nb≥0.7 at room temperature. The X-ray diffraction patterns of the...
Satoshi Kusuda, Atsushi Iwasawa, Osamu Doi, Yutaka Ohya, Norio Yoshizaki
Journal of Poultry Science   48 119-124   May 2011
The structure and mineral composition of eggshell cuticles were studied in 5 species of birds. The approximate thickness of the cuticle layer at the top of shell columns was about 1 μm in the Red Junglefowl (Gallus gallus), about 130 μm in the Whi...
Takayuki Ban, Yusuke Tanaka, Yutaka Ohya
Thin Solid Films   519 3468-3474   Mar 2011
The fabrication of dense or porous titania films by the sol-gel method using anatase colloidal solutions was examined. When anatase colloidal solutions without surfactants were deposited on a substrate, the anatase films thus obtained had a relati...
Takayuki Ban, Yusuke Tanaka, Yutaka Ohya
Journal of Nanoparticle Research   13 273-281   Jan 2011
Transparent colloidal aqueous solutions of anatase nanocrystals were hydrothermally synthesized from aqueous transparent sols with tetramethylammonium titanate colloids, the surfaces of which were modified with citric acid, by structural conversio...
A. Iwasawa, M. Uzawa, M. A. Rahman, Y. Ohya, N. Yoshizaki
Poultry Science   88 2670-2676   Dec 2009
Two calcified structures, the eggshell and sperm-associated body (SB), are present in the eggs of the Japanese quail, Coturnix japonica. X-ray diffractometry showed that calcium carbonates take the form of calcite in the eggshell and aragonite in ...
Takayuki Ban, Naoya Nakashima, Tomohiko Nakatani, Yutaka Ohya
Journal of the American Ceramic Society   92 1230-1235   Jun 2009
We hydrothermally synthesized anatase films on Ti substrates from transparent aqueous solutions of layered titanate colloids. The morphology and wetting properties of the films were examined. The films consisted of columnar aggregates grown on the...
Y. Okazaki, H. Ohashi, Y. Ohya, S. Yanase, S. Hashi
Journal of Optoelectronics and Advanced Materials   10 1089-1092   May 2008
Magnetic properties related to nano-structure have been investigated for sol-gel grown Co-ferrite thin films on the substrates of glass and SiO 2(100). The magnetic properties depended on the annealing temperature and the coercivity of 7.7 kOe was...
Y. Okazaki, H. Ohashi, Y. Ohya, S. Yanase, S. Hashi
INTERMAG 2006 - IEEE International Magnetics Conference   217   Dec 2006
N. Rani Panicker, V. Kumar, Y. Ohya, Y. Takahashi
Ferroelectrics   325 49-54   Dec 2005
Chelating ligands are very effective for the preparation of homogeneous ceramic solid solutions. Lead zirconate titanate (PZT) nanocrystalline powder with a composition near morphotropic phase boundary was prepared by a co-precipitation method usi...
Takayuki Ban, Hideki Mitaku, Chiharu Suzuki, Takashi Kume, Yutaka Ohya, Yasutaka Takahashi
Journal of Porous Materials   12 255-263   Oct 2005
Aqueous silicate solutions could be prepared from a silicon alkoxide using amines as a base. The synthesis of silicalite-1 conducted by hydrothermally treating the solutions after the addition of NPr n4Br (TPABr), was examined focusing on triethyl...
Yutaka Ohya, Takashi Kume, Takayuki Ban
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers   44 1919-1922   Apr 2005
A thin-film transistor consisting of a ZnO active layer and a ZrO 2 insulating layer was fabricated on a tin-doped indium oxide sputtered glass substrate as well as on a SiO2/Si wafer. The ZnO and ZrO2 layers were deposited by a sol-gel, dip-coati...
Yutaka Ohya, Tsukasa Niwa, Takayuki Ban, Yasutaka Takahashi
Journal of Sol-Gel Science and Technology   33 323-326   Mar 2005
Heterostack films of p-type NiO and n-type TiO2 semiconductors were deposited by a method of chemical solution deposition on a glass substrate having a sputtered ITO (In2O3 doped with Sn) electrode. Transparent films with total thickness of about ...
Takayuki Ban, Hideki Mitaku, Chiharu Suzuki, Jun Matsuba, Yutaka Ohya, Yasutaka Takahashi
Journal of Crystal Growth   274 594-602   Feb 2005
Silicalite-1 was synthesized by hydrothermally treating aqueous mixture suspensions of NPrn4Br (TPABr)-dispersed silica gel and different amines. Influence of the type of the amines on crystallization of silicalite-1 and the resultant crystal shap...
Yutaka Ohya, Takatomo Ogata, Takayuki Ban, Yasutaka Takahashi
Journal of the Ceramic Society of Japan   113 220-225   Jan 2005
Zinc oxide thin films were fabricated via a sol-gel method using zinc acetate as a starting reagent. The precursors used were modified with ethanolamines and/or α-hydroxyketones, and their derivatives. Oriented films with the c-axis perpendicular ...
Tomokazu Ohya, Masamichi Ito, Keiko Yamada, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of Sol-Gel Science and Technology   30 71-81   May 2004
Aqueous titanate sols were prepared by reactions of titanium tetraisopropoxide (TIP) with α-hydroxycarboxylic acids in water. IR and Raman spectra, and elemental analyses of the precipitates obtained from the sols revealed that the carboxylates we...
Syukri Arief, Tomoaki Terazawa, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Materials Science and Engineering B: Solid-State Materials for Advanced Technology   100 132-135   Jul 2003
A new approach to form patterned Ni films on the glass substrates has been proposed. The patterning is based on the photo-sensitivity of organically modified nickel gel films. The combination of acetol and monoethanolamine was found to show the ex...
Takayuri Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of Sol-Gel Science and Technology   27 363-372   Jul 2003
A clear alcoholic solution of titanium alkoxide with an addition of various alkanolamines is suitable for a sol-gel coating of titania films. The reaction of titanium isopropoxide, Ti(OPri)4 (TIP), with alkanolamines, such as triethanolamine (TEAH...
Takayuki Ban, Satoshi Kondoh, Tomokazu Ohya, Yutaka Ohya, Yasutaka Takahashi
Journal of Photochemistry and Photobiology A: Chemistry   156 219-225   Mar 2003
Photocatalysis of a transparent titanate aqueous sol, which was prepared by mixing titanium isopropoxide and tetramethylammonium hydroxide or triethylamine, followed by diluting with water, was examined via the photo-fading of rhodamine B. An irra...
Syukri, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Materials Chemistry and Physics   78 645-649   Feb 2003
A new process for the synthesis of metallic Ni, and Ni-Co alloy nanoparticles at a relatively low temperature is reported. The process consists of heating a precursor containing a methyl hydrazine complex of the respective metal ions in nitrogen a...
Tomokazu Ohya, Aki Nakayama, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Bulletin of the Chemical Society of Japan   76 429-435   Feb 2003
UV irradiation on films prepared by a spin-coating method using aqueous titanate sols was investigated. The transparent sols used in this study were prepared by a reaction of titanium tetraisopropoxide (TIP) with tetramethylammonium hydroxide (TMA...
Tomokazu Ohya, Aki Nakayama, Yukio Shibata, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of Sol-Gel Science and Technology   26 799-802   Jan 2003
Dip- or spin-coating and characterization of titania (TiO 2 ) thin films from various aqueous solutions have been studied. The aqueous titanium solutions mainly used in this study were halogen- and chelate-free solutions with the concentrations up...
Syukri, Yusuke Ito, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Thin Solid Films   422 48-54   Dec 2002
A modified version of the dip-coating technique, which uses 2-hydroxylhydrazine as a mild reducing agent, was applied in the fabrication of nickel thin films. Nickel acetate was used as metal source. Metallic nickel thin films were formed on glass...
Y. Ohya, T. Tamakoshi, T. Ban, Y. Takahashi
IEEE International Symposium on Applications of Ferroelectrics   467-470   Dec 2002
Lead zirconate titanate (PZT) films were fabricated by a sol-gel method. The sol was prepared using Ti(OiPr)4, Pb(OAc)2·3H2O, Zr(OnBu)4, and diethanolamine (DBA) with a molar ratio of DEA/(Ti+Zr)=1. They were dissolved in isopropanol solvent. The ...
Syukri, T. Ban, Y. Ohya, Y. Takahashi
Journal of Materials Science Letters   21 1449-1451   Sep 2002
A new approach to deposit copper thin films by dip-coating technique is presented. Uniform, well-densified and crack free copper thin films can be easily prepared from copper acetate precursor by using DEA as additive. Films grown at low temperatu...
Tomokazu Ohya, Miki Kabata, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of Sol-Gel Science and Technology   25 43-50   Aug 2002
The stabilization effects of α-hydroxyketones such as acetoin, acetol, and their imine derivatives of monoethanolamine (MEA) on the 2-propanol solution of metal alkoxides (Al, Ti, Zr, Nb and Ta) were investigated. The hydroxyketones, especially ac...
Tomokazu Ohya, Aki Nakayama, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Chemistry of Materials   14 3082-3089   Jul 2002
Transparent, aqueous colloidal titanate solutions were prepared by a reaction between titanium alkoxide and alkylamines or tetraalkylammonium hydroxides. The chemical species containing titanium atoms were found to be a colloidal particle (15 nm) ...
Masaki Matsui, Yasuhiro Yoshimura, Tomokazu Ohya, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Bulletin of the Chemical Society of Japan   75 589-593   Mar 2002
Zirconia gel films were prepared by a dipping method from a 2-propanol solution of zirconium tetra-n-butoxide (ZTNB) stabilized with diethanolamine (DEA) and acetoin. In the case of the ZTNB-DEA system, crystallization to zirconia occurred at 480 ...
Yutaka Ohya, Kazuhiro Horinouchi, Takayuki Ban, Yasutaka Takahashi, Norimitsu Murayama
Journal of the Ceramic Society of Japan   110 950-953   Jan 2002
Al2O3/SnO2 multilayered films were fabricated via the sol-gel method using iPrOH solutions of Sn(iOPr)4 and Al(iOPr)3, which were prepared by adding triethanolamine. Coating was accomplished by a dip-coating procedure. Doping with Pt and surface m...
Yutaka Ohya, Satoru Itoda, Takayuki Ban, Yasutaka Takahashi
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers   41 270-274   Jan 2002
Sol modified with diethanolamine was used for the preparation of thick lead zirconate titanate (PZT) films. The deposited films crystallized in the perovskite structure by heating above 600°C. Thick film with 3 μm single-coating thickness was obta...
Miaoliang Huang, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Chinese Journal of Catalysis   22 76   Dec 2001
Uniform and crack-free TiO 2 thin films with highly-dispersed platinum were prepared from i-PrOH-TTIP-DEA-H 2 O system containing H 2 PtCl 6 ·6H 2 O as metal source by sol-gel method. The microstructure and morphology of the films were characteriz...
Radhouane Bel Hadj Tahar, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of the American Ceramic Society   84 85-91   Jan 2001
Thin films of dicadmium stannate spinel (Cd2SnO4) were deposited on glass substrates using a dip-coating technique. The films were transparent to visible light (90%) and electrically conductive. X-ray diffractometry showed that annealed films cons...
Yutaka Ohya, Zenbe E. Nakagawa, Kenya Hamano, Hiroshi Kawamoto, Satoshi Kitaoka
Materials Research Society Symposium - Proceedings   658    Jan 2001
A microstructural change during the formation reaction of aluminum titanate from a mixture of rutile and corundum powders has been studied. The characterization was carried out using a polarization microscope, a scanning electron microscope and a ...
Y. Ohya, T. Niwa, T. Ban, Y. Takahashi
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers   40 297-298   Jan 2001
A ZnO thin film was deposited on a Si wafer having an oxidized SiO2layer using a chemical solution deposition process and was applied to a bottom-gate type thin film transistor (TFT). The films prepared by combined heating at 600° and 900°C exhibi...
Yutaka Ohya, Syouko Ito, Takayuki Ban, Yasutaka Takahashi
Key Engineering Materials   113-116   Dec 2000
Copper (II) oxide thin films doped with Li and Al were prepared by a liquid phase method on glass substrate. The used reagents were mainly Cu(OAc)2, Al(iOPr)3 and LiOAc. The films were crystallized as black CuO crystal by heating above 300°C. The ...
Takashi Sato, Yoshinari S.A. Wabe, Yutaka Ohya, Mikio Sugai, Zenbe E. Nakagawa
Journal of the Ceramic Society of Japan   108 345-349   Jan 2000
Cracking of a cristobalite-containing mullite body at the middle stage of crystallization during cooling was investigated by acoustic emission (AE) and the crack formation was discussed. The specimen was composed of an outside layer of crystalline...
Yutaka Ohya, Tomokazu Ito, Masahiro Kaneko, Takayuki Ban, Yasutaka Takahashi
Journal of the Ceramic Society of Japan   108 803-806   Jan 2000
Solid solubility of SnO2in In2O3was investigated in the interval between 1000 to 1500°C. Samples were prepared using In2O3powder and tin alkoxide solution, as well as mixed solution of indium and tin alkoxides. X-ray diffraction analysis revealed ...
Yasutaka Takahashi, Ayako Ohsugi, Takeshi Arafuka, Tomokazu Ohya, Takayuki Ban, Yutaka Ohya
Journal of Sol-Gel Science and Technology   17 227-238   Jan 2000
The effects of several hydroxyketones such as acetol, acetoin, γ-ketobutanol themselves and their combinations with monoethanolamine (MEA) or ethylenediamine (ED) on the stabilization of titanium tetraisopropoxide (TTIP) in isopropanol solution ar...
Takayuki Ban, Satoshi Kondoh, Yutaka Ohya, Yasutaka Takahashi
Physical Chemistry Chemical Physics   1 5745-5752   Dec 1999
Photocatalytic properties of TS-1 zeolite were examined via a degradation reaction of monoethanolamine (MEA). When TS-1 was mixed with MEA aqueous solution, the MEA molecules were bonded to the Ti atoms in TS-1 since the latter were coordinatively...
Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of the American Ceramic Society   82 22-26   Dec 1999
MgO-SiO 2 precursor gels were prepared by mixing tetramethoxysilane (TMOS) or tetraethoxysilane (TEOS), H 2O, and magnesium metal in methanol. Forsterite (Mg 2SiO 4) and orthoenstatite (MgSiO 3) were crystallized from their precursors at temperatu...
Takayuki Ban, Takafumi Ohwaki, Yutaka Ohya, Yasutaka Takahashi
Angewandte Chemie - International Edition   38 3324-3326   Nov 1999
Growth of oriented seed crystals on a substrate led to a completely oriented and continuous membrane of LTA-type zeolite. The seed crystals of cubic morphology were dip-coated onto a tilted substrate (see schematic diagram) with the zeolite channe...
Yutaka Ohya, Jyunji Mishina, Tatsuya Matsuda, Takayuki Ban, Yasutaka Takahashi
Journal of the American Ceramic Society   82 2601-2606   Oct 1999
Sol-gel TiO2thin films were fabricated at 650 °C using sol that was derived from the Ti(OiPr)4-diethanolamine-H2O-iPrOH system. Repeated deposition and rapid heating resulted in columnar grains, whereas slow heating - at a rate of 10°-20 °C/min - ...
Takayuki Ban, Takafumi Ohwaki, Yutaka Ohya, Yasutaka Takahashi
International Journal of Inorganic Materials   1 243-251   Sep 1999
Influences of the addition of alkanolamines and alkylammonium hydroxide into the starting suspensions on the shape and the size of zeolite-A (NaAlSiO4·xH2O) particles were investigated by optical microscopy and liquid-state NMR measurements. Zeoli...
Yutaka Ohya, Yasutaka Takahashi, Minori Murata, Zenbe E. Nakagawa, Kenya Hamano
Journal of the American Ceramic Society   82 445-448   Feb 1999
Quartz grains in porcelain bodies cause cracking. Under the present conditions, acoustic emission (AE) has shown that the cracking occurred in a temperature range of 900°-800°C during cooling from firing at a temperature of 1200°C. This cracking c...
Takashi Sato, Yoshinari Sawabe, Yutaka Ohya, Mikio Sugai, Zenbe E. Nakagawa
Journal of the Ceramic Society of Japan   107 838-843   Jan 1999
Crystallization of glass phase to cristobalite was investigated in mullite-glass ceramics with excess SiO2 compositions (5.3-16.4 mass%), namely, higher than stoichiometric mullite. Starting powders were prepared by alkoxide hydrolysis method. Com...
Yutaka Ohya
Journal of Materials Synthesis and Processing   6 237-241   Dec 1998
We describe here the results of fabrication of NiO thin films and their gas sensing properties. The NiO thin film was prepared by a liquid phase method using Ni(OAc)2·4H2O as a starting reagent. After dissolving into iPrOH with the addition of die...
Viswanathan Kumar, Yutaka Ohya, Yasutaka Takahashi
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers   37 4477-4481   Aug 1998
Ferroelectric thin films of PbTiO3 and Pb(Zr0.5Ti0.5)O3 were deposited using a sol-gel process from a highly stable precursor solution derived from a unique and simple system consisting of basic lead acetate, titanium and zirconium butoxides. This...
Yutaka Ohya, Hiroki Koyama, Takayuki Ban, Yasutaka Takahashi
Materials Science and Engineering B   B54 55-59   Jun 1998
A p-type semiconductor, NiO, and n-type semiconductors, ZnO and TiO2, were used for making a p-n contact. These oxide semiconductor films were prepared by a liquid phase method using zinc and nickel acetates, titanium tetraisopropoixde and diethan...
Radhouane Bel Hadj Tahar, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of the American Ceramic Society   81 321-327   Feb 1998
Metal-doped indium oxide thin films that have been prepared on glass substrates via a dip-coating method from an aqueous sol show a rapid decrease in electrical conductivity at room temperature (by approximately three orders of magnitude) when bro...
Radhouane Bel Hadj Tahar, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of Applied Physics   83 2631-2645   Jan 1998
Tin doped indium oxide (ITO) films are highly transparent in the visible region, exhibiting high reflectance in the infrared region, and having nearly metallic conductivity. Owing to this unusual combination of electrical and optical properties, t...
Radhouane Bel Hadj Tahar, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of Applied Physics   83 2139-2141   Jan 1998
Hall effect measurements have been performed on tin-doped indium oxide thin films prepared by the dipping method. The apparent variation of electron mobility with carrier concentration in these films has been quantitatively interpreted in terms of...
Koichiro Hayashi, Masahiro Hosokawa, Tsukasa Yoshida, Yutaka Ohya, Yasutaka Takahashi, Osamu Yamamoto, Hideki Minoura
Materials Science and Engineering B   49 239-242   Oct 1997
A composite film composed of strontium doped lanthanum manganite (SLM), La0.9Sr0.1MnO3 and yttria stabilized zirconia (YSZ), (ZrO2)0.96(Y2O3)0.04, has been successfully prepared by metal-organic decomposition (MOD) at temperatures of 800-1000°C us...
Radhouane Bel Hadj Tahar, Takayuki Ban, Yutaka Ohya, Yasutaka Takahashi
Journal of Applied Physics   82 865-870   Jul 1997
This article reports the fabrication of thin films of In2O3 from an aqueous sol and an organic solution. The stability of the aqueous sol with respect to the concentration of indium and pH are discussed. Thermo-gravimetric and differential thermal...
Yasutaka Takahashi, Shinya Okada, Radhouane Bel Hadj Tahar, Ken Nakano, Takayuki Ban, Yutaka Ohya
Journal of Non-Crystalline Solids   218 129-134   Jan 1997
Uniform, transparent indium tin oxide (ITO) films were prepared by dip-coating process using an organic sol composed of indium acetate-diethanolamine-tin octylate-n-propanol mixture and the relationship between their electrical properties, film mo...
Yutaka Ohya, Masayoshi Ueda, Yasutaka Takahashi
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers   35 4738-4742   Dec 1996
A p-type oxide thin film, NiO, and an n-type thin film, ZnO, were fabricated by a liquid phase method using metal acetates as starting reagents. Both the films were transparent, uniform in thickness and porous. By repetition of coating of the n- a...
Viswanathan Kumar, Ramadoss Marimuthu, Shashikumar G. Patil, Yutaka Ohya, Yasutaka Takahashi
Journal of the American Ceramic Society   79 2775-2778   Oct 1996
This paper reports a new system for the preparation of lead titanate powders by the sol-gel method. In this system basic lead acetate, (CH3COO)2Pb·Pb(OH)2, is used as the lead precursor instead of the widely used Pb(OOCCH3)2·3H2O and titanium tetr...
Yutaka Ohya, Hisao Saiki, Toshimasa Tanaka, Yasutaka Takahashi
Journal of the American Ceramic Society   79 825-830   Jan 1996
Titanium dioxide and zinc oxide films were fabricated by spin-on and dip-coating methods. Both types of films exhibited columnar grains when the single coating was thin, ∼10 nm. The columnar TiO2 films were dense, as confirmed by their density val...
Y. Ohya, Z. Nakagawa
Journal of Materials Science   31 1555-1559   Jan 1996
Grain-boundary crack onset and crack volume at room temperature resulting from thermal expansion anisotropy in aluminium titanate ceramics were studied by dilatometry. Investigation revealed that specimens with low bulk density have a smaller temp...
Y. Ohya, Y. Takahashi, Z. Nakagawa
Journal of Materials Science   31 1361-1365   Jan 1996
The relation between thermal expansion coefficient and grain-boundary crack volume of aluminium titanate ceramics has been calculated based on the thermal expansion data of a single crystal. The calculation began with the drawing of a frequency di...
M. Kanamori, K. Suzuki, T. Yamada, Y. Ohya, Y. Takahashi
Yogyo Kyokai Shi/Journal of the Ceramic Society of Japan   103 1258-1263   Dec 1995
The long-term variations in the resistivity of SnO 2 films in air containing water vapor or reducing gas (denoted as wet air or test gas, respectively) were investigated quantitatively. Analyses of electronic properties, weight increase, film str...
M. Kanamori, K. Suzuki, T. Yamada, Y. Ohya, Y. Takahashi
Yogyo Kyokai Shi/Journal of the Ceramic Society of Japan   103 1258-1263   Dec 1995
The long-term variations in the resistivity of SnO2 films in air containing water vapor or reducing gas (denoted as wet air or test gas, respectively) were investigated quantitatively. Analyses of electronic properties, weight increase, film struc...
Masaaki Kanamori, Yoshiki Okamoto, Yutaka Ohya, Yasutaka Takahashi
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   103 113-116   Feb 1995
Sensitivity of SnO2 thin-film gas sensors which were fabricated by the dip-coating method was found to exponentially increase with the decrease in film thickness. This could be ascribed to the substantial increase in the resistivity of the films i...
Duan Fen Qian, Yutaka Ohya, Zenbe e. Nakagawa, Kenya Hamano
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   103 1022-1026   Jan 1995
Aluminum titanate ceramics were fabricated from compacts of aggregated mixture of alumina and titania. The mixture was prepared by precipitation of aluminum hydroxide from aqueous solution of aluminum nitrate, containing rutile powder. After calci...
Masaaki Kanamori, Hideki Ohtake, Yutaka Ohya, Yasutaka Takahashi
Journal of the Ceramic Society of Japan. International ed.   103 58-62   Jan 1995
The effects of IV group element (Zr, Ti, Ge, Si) oxides addition on the grain growth of SnO2 thin films at elevated temperature (600°-1000°C) were investigated. It was found that addition of 10mol% GeO2 controlled the grain growth of SnO2 effectiv...
Yasutaka Takahashi, Masaaki Kanamori, Masaaki Kanamori, Akiko Kondoh, Hideki Minoutia, Yutaka Ohya
Japanese Journal of Applied Physics   33 6611-6615   Dec 1994
Electrical and photoelectrical properties of nondoped and doped zinc oxide films coated on glass plates by the dip-coating method are investigated at room temperature in various ambient atmospheres. The dark conductivity of the nondoped films expo...
Masaaki Kanamori, Kiyohiro Suzuki, Yutaka Ohya, Yasutaka Takahashi
Japanese Journal of Applied Physics   33 668-663   Jan 1994
Electrical properties and the number of unpaired electrons localized in oxygen vacancies of SnO 2 thin films were quantitatively analyzed using the van der Pauw method and ESR spectra, respectively, in order to clarify the source of carrier electr...
Yasutaka Takahashi, Masaaki Kanamori, Akiko Kondoh, Hideki Minoura, Yutaka Ohya
Japanese Journal of Applied Physics   33 661-665   Jan 1994
Electrical and photoelectrical properties of nondoped and doped zinc oxide films coated on glass plates by the dip-coating method are investigated at room temperature in various ambient atmospheres. The dark conductivity of the nondoped films expo...
Yutaka Ohya, Takashi Ito, Yasutaka Takahashi
Japanese Journal of Applied Physics   33 5272-5276   Jan 1994
Multilayered thin films of ferroelectric perovskites were fabricated by the sol-gel method. The investigated films were PbTiO3, PbZrO3, BaTiO3and SrTiO3, and their multilayered films. The films were prepared by dipping and heating in air at 600-70...
Y. Ohya, H. Saiki, Y. Takahashi
Journal of Materials Science   29 4099-4103   Jan 1994
Very uniform and transparent zinc oxide thin films doped with aluminium and indium were fabricated by the dip-coating technique using solutions prepared by the ethanolamine method. As starting materials, zinc acetate and zinc n-propoxide were used...
Y. Ohya, M. J. Hoffmann, G. Petzow
Journal of Materials Science Letters   12 149-152   Feb 1993
Yutaka Ohya, Toshimasa Tanaka, Yasutaka Takahashi
Japanese Journal of Applied Physics   32 4163-4167   Jan 1993
Lead zirconate titanate (PZT) films with the composition of Pb(ZrxTi1-x)O3 (x: 0.2-0.8) were fabricated by dip-coating methods. The sol was prepared using ethanolamine as a sol stabilizer. The substrate was In2O3:Sn (ITO) sputtered glass (Corning ...
Yutaka Ohya, Michael J. Hoffmann, Günter Petzow
Journal of the American Ceramic Society   75 2479-2483   Jan 1992
TiB 2 ‐particle reinforcement is one of the most successful methods for improving the fracture toughness of SiC ceramics. 1–3 Commercially available TiB 2 powders, however, have a large particle size and/or are highly reactive so that they are not...
Yutaka Ohya, Yutaka Ohya, Michael J. Hoffmann, Michael J. Hoffmann, Günter Petzow, Günter Petzow
Journal of the American Ceramic Society   75 2479-2483   Jan 1992
TiB2-particle reinforcement is one of the most successful methods for improving the fracture toughness of SIC ceramics.1-3Commercially available TiB2powders, however, have a large particle size and/or are highly reactive so that they are not favor...
Tae Hyun Sung, Zenbe e. Nakagawa, Shigeru Arima, Yasuro Ikuma, Yutaka Ohya, Nobuo Ishizawa, Masahiro Yoshimura
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   97 1005-1008   Dec 1989
The crystallization mechanism of an amorphous Bi2Sr2Ca2Cu3Oy phase was studied from the relations between crystallization and volume changes by dilatometry. Further, the effect of addition of CdO on the crystallization mechanism and superconductiv...
Tae Hyun Sung, Katsunori Takahashi, Yutaka Ohya, Yoshiki Takagi, Zenbe e. Nakagawa, Tetsuro Nakamura, Yasutoshi Saito
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   97 1039-1043   Dec 1989
BYCO was synthesized from a mixture using Ba(NO2)2as a Ba source. The thermal analysis, phase changes and thermal shrinkage during heating of the mixture were investigated, and compared with those of a mixture using BaCO3. For small specimen sizes...
Mitsuo Shimbo, Zenbe e. Nakagawa, Yutaka Ohya, Kenya Hamano
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   97 857-863   Dec 1989
Crystal growth of MgO doped with AlF3 and MgF2 has been studied by BET method and X-ray powder diffractometry. The fluorides were hydrolyzed by the water contained in MgO powder above 500°C and generated HF gas, which was adsorbed on the surface o...
Mitsuo Shimbo, Zenbe e. Kakagawa, Yutaka Ohya, Kenya Hamano
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan   97 640-644   Dec 1989
The effect of HF on the decomposition of brucite was studied by differential thermal analysis (DTA) and X-ray powder diffraction (XRD). HF was added to brucite by addition of fluoride or by treatment with hydrofluoric acid solutions. In fluoride a...
Yutaka Ohya, Zenbe‐e ‐e Nakagawa, Kenya Hamano
Journal of the American Ceramic Society   71    Jan 1988
Bending strength and Young's modulus of aluminum titanate ceramics at room temperature to 1300°C were examined. Bending strength increased from 62 MPa at room temperature to 280 MPa at 1100°C. Young's modulus also increased, to 99 GPa at 1100°C. T...
Masahiro Yoshimura, Tae Hyun Sung, Shigeru Arima, Yutaka Ohya, Sakae Tsutai, Nobuo Ishizawa, Hideomi Koinuma, Zenbe e. Nakagawa
Journal of the Japan Society of Powder and Powder Metallurgy   35 974-978   Jan 1988
Substitution of Cd for Ca in Bi2Sr2Ca2Cu3Oy has been studied by using rapid quenching after rapid melting technique. Amorphous materials containing a small amount of CaO phase were obtained as films with about 20 μm thickness. Annealing of the fil...
Yutaka Ohya, Zenbe‐e ‐e Nakagawa, Kenya Hamano
Journal of the American Ceramic Society   70    Jan 1987
The relation between grain size and grain‐boundary microcracking during cooling in aluminum titanate ceramics was studied. Microcracking temperature was determined by the measurement of thermal contraction and expansion, which was accompanied by a...
Kenya Hamano, Zenbe e. Nakagawa, Takao Kanai, Yutaka Ohya, Minori Hasegawa
Report of the Research Laboratory of Engineering Materials Tokyo   93-102   Jan 1986
The replacement of chloride for hydroxide mixture having the stoichiometric Mg-Al spinel composition affected the formation ratio of spinel, and properties and sinterability of calcined powder. The addition of chlorides decreased the decomposition...
Yutaka Ohya, Kenya Hamano, Zenbe e. Nakagawa
Yogyo Kyokai Shi/Journal of the Ceramic Society of Japan   94 665-670   Jan 1986
Effects of four additives on the microstructure and bending strength of aluminum titanate ceramics were investigated. The grain size of aluminum titanate in fired specimens increased with increasing firing temperature, but decreased with the addit...
Kenya Hamano, Chii Shyang Hwang, Zenbe e. Nakagawa, Yutaka Ohya
Yogyo Kyokai Shi/Journal of the Ceramic Society of Japan   94 505-511   Jan 1986
The effects of TiO//2 addition on the sintering process and microstructure of alumnina ceramics were studied. In air, the solid solubility of TiO//2 in alpha -Al//2O//3 was to small to be determined by the lattice parameter shift of alpha -Al//2O/...
Kenya Hamano, Yutaka Ohya, Zenbe e. Nakagawa
International Journal of High Technology Ceramics   1 129-137   Jan 1985
The crack propagation behaviour of aluminium titanate ceramics containing grain boundary microcracks has been investigated. The mean grain size of the aluminium titanate was 0·6 μm at 1300°C and 2·3 μm at 1500°C. Specimens sintered at 1450 and 150...
Duan Fen Qian, Yutaka Ohya, Kenya Hamano, Zenbe e. Nakagawa
Yogyo Kyokai Shi/Journal of the Ceramic Society of Japan   93 315-321   Jan 1985
Effects of excess Al//2O//3 on microstructure and mechanical and thermal properties of aluminum titanate ceramics prepared from aqueous solutions of aluminum nitrate and rutile were investigated. All specimens with the Al//2O//3/TiO//2 molar ratio...
Kenya Hamano, Zenbe e. Nakagawa, Shoichiro Enmei, Yutaka Ohya, Minori Hasegawa
Report of the Research Laboratory of Engineering Materials Tokyo   65-77   Jan 1985
Porous spinel ceramics with variations of the composition ratio of MgO/Al//2O//3 and substitution of 5 and 10 mol% Cr//2O//3 for Al//2O//3 were prepared by calcination of freeze-dried sulfates at 1300 degree C for 1 h and firing at 1350 degree C f...
Yutaka Ohya, Kenya Hamano, Zenbe e. Nakagawa
Yogyo Kyokai Shi/Journal of the Ceramic Society of Japan   92 261-267   Dec 1984
The effect of Fe//2O//3 addition of the formation of A//2TiO//5, microstructure and bending strength of Al//2TiO//4 ceramics were investigated. Various amounts of Fe//2O//3 from 0. 01 to 5 wt% were added into equimolar mixture of corundum and ruti...
Yutaka Ohya, Kenya Hamano, Zenbe e. Nakagawa
Yogyo Kyokai Shi/Journal of the Ceramic Society of Japan   91 289-297   Jun 1983
Relations among microstructure, bending strength and thermal expansion behavior of the aluminum titanate ceramic were investigated. The ceramics were prepared from three kinds of synthesized powders having several grain sizes and various amounts o...
大矢 豊
セラミックス   31(12) 1025-1028

Books etc

 
Handbook of Nanoceramics and Their Based Nanodevices
OHYA Yutaka (Part:Joint Work, Vol. 4, Chapter 1, p.1-49, “Sol-Gel Oxide Thin Films for Electronic Applications and Their Microstructure”)
American Scientific Publishers   2009   
Handbook of Sol-Gel Science and Technology
OHYA Yutaka (Part:Joint Work, Volume I, Sol-gel Processing, Chapter 5, “Aqueous Precursors”, pp.105-126)
Kluwer Academic Publishers   2005   

Conference Activities & Talks

 
KOJIMA Satoru, SHINMURA Shoji, KASHIWAKURA Nobuo, OHYA Yutaka, YOSHIDA Satoshi
工学・工業教育研究講演会講演論文集   6 Aug 2009   
Aluminum titanate refractories for molten aluminum [Invited]
Yutaka OHYA
12th International Ceramics Congress   Jun 2010   12th International Ceramics Congress
ELECTRICAL AND OPTICAL PROPERTIES OFSOL-GEL ZNO THIN FILMS [Invited]
Yutaka OHYA
International Workshop on Advanced Ceramics   Oct 2006   International Workshopon Advanced Ceramics
FUJII SOTA, OYA YUTAKA, BAN TAKAYUKI
日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)   1 Sep 2015   
KONDO YASUHIKO, BAN TAKAYUKI, OYA YUTAKA
日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)   1 Sep 2015   

Works

 
Development of aluminium alloy casting system using aluminum titanate ceramics parts
2000
Microstructure Controll of Gas-Sensing Materials
2001

Research Grants & Projects

 
Ministry of Education, Culture, Sports, Science and Technology: Grants-in-Aid for Scientific Research(基盤研究(B))
Project Year: 1998 - 2000    Investigator(s): Yasutaka TAKAHASHI
The results of this investigation were published as the papers, patents or oral presentations in the relevant societies, and they are classified as follows :(1) α-hydroxyketones and their imine derivatives as new alkoxide stabilizers (modifiers).(...
Ministry of Education, Culture, Sports, Science and Technology: Grants-in-Aid for Scientific Research(基盤研究(B))
Project Year: 1996 - 1997    Investigator(s): Yasutaka TAKAHASHI
Both an organic sol system derived from indium acetate and aqueous sol system consisted of indium hydroxide were investigated. The results obtained through the investigation are summarized as follows :(1) The organic sol system affords more densif...
Ministry of Education, Culture, Sports, Science and Technology: Grants-in-Aid for Scientific Research(基盤研究(C))
Project Year: 2011 - 2013    Investigator(s): Yutaka OHYA
Aqueous precursors for titania and silica were prepared using titan tetraisopropoxide and silicon tetraethoxide, respectively, with addition of tetramethylammonium hydroxide. Appropriate amount of the two precursors were mixed and silica-titania c...
Japan Society for the Promotion of Science: Grants-in-Aid for Scientific Research
Project Year: 2011 - 2013
Ministry of Education, Culture, Sports, Science and Technology: Grants-in-Aid for Scientific Research(一般研究(C))
Project Year: 1988 - 1989    Investigator(s): Zenbe-e NAKAGAWA
Amorphous materials which have a stoichiometric composition of mullite as an oxide were obtained by hydrolysis of mixture of aluminum isopropoxide and methylsilicate. When the hydrolysis was treated rapidly, prepared material crystallized to spine...

Patents

 
5540225 : MOLTEN-METAL CONTACT MATERIAL AND COATING FILM
OYA YUTAKA,SAKURADA OSAMU,TANAKA MAKOTO,KITAOKA SATOSHI,KAWASHIMA NAOKI,KASHIWAGI KAZUMI
5554934 : SPINEL PRECURSOR SOL, METHOD FOR MANUFACTURING THE SAME AND METHOD FOR MANUFACTURING ALUMINUM TITANATE SINTERED COMPACT COATED WITH THE SPINEL
OYA YUTAKA,BAN TAKAYUKI,KITAOKA SATOSHI
5780588 : α-ALUMINUMOXIDEPRECURSORSOL,METHODFORPRODUCINGTHESAME,ANDMETHODFORPRODUCINGYTTRIUM-ALUMINUM-GARNET
SAKURADAOSAMU,OYAMAHIROSHI,YOSHIDAMICHIYUKI,OYAYUTAKA,TANAKAMAKOTO,KITAOKASATOSHI