IWADATE Yasuhiko

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Name
IWADATE Yasuhiko
Affiliation
Chiba University
Section
Graduate School of Engineering, Applied Chemistry and Biotechnology
Job title
Professor
Degree
Doctor of Engineering(Tokyo Institute of Technology), Master of Engineering(Chiba University)

Research Areas

 
 

Academic & Professional Experience

 
 
   
 
(University of Paris)
 
1982
 - 
1983
CNRS(France), Associate Researcher
 
1984
 - 
1992
Chiba University, Research Associate
 
1992
 - 
2001
Chiba University, Associate Professor
 
2001
   
 
- Chiba University, Professor
 

Education

 
 
 - 
1982
Division of Science and Engineering), Graduate School, Tokyo Institute of Technology
 
 
 - 
1979
Synthetic Chemistry, Graduate Course of Engineering, Graduate School of Chiba University
 
 
 - 
1977
Faculty of Engineering, Chiba University
 

Committee Memberships

 
1999
   
 
CODATA (Committee on Data for Science and Technology of the International Council of Scientific Unions, Paris)  Task Group member (Working group on Molten Salts)
 

Awards & Honors

 
2002
Molten Salt Award
 
2002年度

Misc

 
Takahiro Ohkubo, Moe Ibaraki, Yukio Tachi, Yasuhiko Iwadate
Applied Clay Science   123 148-155   Apr 2016
© 2016 Elsevier B.V. The estimation of water population in water-saturated compacted clay was studied with 1H NMR relaxometry and freezing point depression. The clay samples and saturated condition were Na-montmorillonite at 0.8 and 1.4 g/cm3 satu...
大窪貴洋, 端健二郎, 出口健三, 清水禎, 大友季哉, 岩舘泰彦
ガラスおよびフォトニクス材料討論会講演要旨集   56th 143-144   Nov 2015
岩舘泰彦, 大西亮介, 大窪貴洋
Thermophys Prop   36th 21-23   Oct 2015
久保義貴, 大窪貴洋, 岩舘泰彦, 西山伸
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)   28th ROMBUNNO.1K08   Sep 2015
大窪貴洋, 岩舘泰彦, 舘幸男
日本原子力学会秋の大会予稿集(CD-ROM)   2015 ROMBUNNO.H38   Aug 2015
岡本拓也, 大窪貴洋, 岩舘泰彦, 出口健三, 清水禎, 大木忍, 舘幸男
日本原子力学会秋の大会予稿集(CD-ROM)   2015 ROMBUNNO.H39   Aug 2015
大窪貴洋, 岩舘泰彦, 鈴木賢紀, 梅咲則正, 田中敏宏, 柿原敏明, 橋本拓
日本原子力学会秋の大会予稿集(CD-ROM)   2015 ROMBUNNO.F47   Aug 2015
Takahiro Ohkubo, Ryusuke Monden, Yasuhiko Iwadate, Shinji Kohara, Kenzo Deguchi, Shinobu Ohki, Tadashi Shimizu
Physics and Chemistry of Glasses: European Journal of Glass Science and Technology Part B   56 139-144   Jan 2015
A structural investigation of aluminoborosilicate glasses containing MoO3 (model nuclear waste glasses) was carried out using high energy x-ray diffraction (HEXRD), 29Si, 27Al, 11B MAS and 11B(23Na) REDOR NMR experiments. HEXRD revealed that the o...
Takahiro Ohkubo, Yasuhiko Iwadate, Kenzo Deguchi, Shinobu Ohki, Tadashi Shimizu
Journal of Physics and Chemistry of Solids   77 164-171   Jan 2015
© Elsevier Ltd. All rights reserved. Aqueous corrosion tests were performed for aluminoborosilicate glasses with different Na contents at 90°C for 20 days. Multi-nuclear solid-state nuclear magnetic resonance (NMR) techniques were employed to char...
岩舘泰彦, 望月洋一, 大窪貴洋, 西山伸, 福永俊晴
日本中性子科学会年会講演概要集   15th 52   2015
大窪貴洋, 土田英二, 梅咲則正, 岩舘泰彦
村田学術振興財団年報   (28) 331-338   Dec 2014
久保義貴, 大窪貴洋, 岩舘泰彦
溶融塩化学討論会要旨集   46th 35-36   Nov 2014
大窪貴洋, 岩舘泰彦, 土田英二
ガラスおよびフォトニクス材料討論会講演要旨集   55th 130-131   Nov 2014
Takahiro Ohkubo, Eiji Tsuchida, Yasuhiko Iwadate
Chemical Physics Letters   612 68-72   Sep 2014
We present time-dependent Born effective charges of B and O in lithium borate melts determined by ab initio molecular dynamics (AIMD) simulations. The Born charge, based on polarization theory, is calculated from all atoms at each time step of the...
Yasuhiko Iwadate
Handbook on the Physics and Chemistry of Rare Earths   44 87-168   Jan 2014
There is a definite overlap between the concepts of molten salts and ionic liquids; however, the present tendency is to use "molten salts" to characterize melts of purely inorganic compounds. If theoretical modeling of ionic crystals is relatively...
Yasuhiko Iwadate
Molten Salts Chemistry   17-31   Aug 2013
Octahedral ionic species are known to exist in molten chloride mixtures containing rare earth as well as molten alkali metal chlorides containing UO22+ ions. This phenomenon can be utilized in pyrochemical reprocessing of nuclear spent fuels (MOX ...
Takahiro Ohkubo, Eiji Tsuchida, Mallory Gobet, Mallory Gobet, Vincent Sarou-Kanian, Vincent Sarou-Kanian, Catherine Bessada, Catherine Bessada, Yasuhiko Iwadate
Journal of Physical Chemistry B   117 5668-5674   May 2013
The electronic properties and atomic structure of a molten xLi 2O-(1-x)B2O3 system were investigated by measuring conductivity and using first-principles molecular dynamics (MD) simulations. The conductivities obtained were converted to a Li self-...
Toshiyuki Fujii, Takeshi Uda, Takeshi Uda, Yasuhiko Iwadate, Takayuki Nagai, Akihiro Uehara, Hajimu Yamana
Journal of Nuclear Materials   440 575-579   May 2013
Raman spectra of alkali chloride melts containing 3 mol% U(VI) were measured at 823 K. The complexa-tion of UO2Cl4 2- in binary mixtures of LiClAKCl, LiClARbCl, and LiClACsCl was investigated. The spectrum of UO2Cl4 2- obtained was characterized b...
Takeshi Uda, Takeshi Uda, Toshiyuki Fujii, Yasuhiko Iwadate, Akihiro Uehara, Hajimu Yamana
Zeitschrift fur Anorganische und Allgemeine Chemie   639 765-769   Apr 2013
Raman spectra of rare earth (REE: rare earth elements) trichloride (REE = Y, La, Ce, Pr, Sm, Gd, Dy, or Yb) dissolved in alkali chloride eutectic melts (LiCl-KCl, LiCl-RbCl, and LiCl-CsCl) were measured at 793 K. The spectra showed polarized peaks...
Yasuhiko Iwadate, Takahiro Ohkubo
Zeitschrift fur Naturforschung - Section C Journal of Biosciences   68 A 66-72   Mar 2013
Structural analyses were performed to determine the local structure of liquid TiCl4 using laboratory-scale X-ray diffraction and Raman spectroscopy from which the existence of tetrahedral TiCl4 molecules in the liquid was definitely confirmed. Con...
Takahiro Ohkubo, Akihiro Ohira, Yasuhiko Iwadate
Journal of Physical Chemistry Letters   3 1030-1034   Apr 2012
An NMR method was applied for the deconvolution of specific water in sulfonated polyether sulfone membranes, where sulfonated polyethersulfone is a proton-conducting polymer in polymer electrolyte membrane fuel cells. The distribution of 1H longit...
Takahiro Ohkubo, Mallory Gobet, Mallory Gobet, Vincent Sarou-Kanian, Vincent Sarou-Kanian, Catherine Bessada, Catherine Bessada, Muneharu Nozawa, Yasuhiko Iwadate
Chemical Physics Letters   530 61-63   Mar 2012
Lithium diffusion was measured in xLi 2O-(1 - x)B 2O 3 melts as a function of temperature and composition by high-temperature pulsed field gradient NMR. The 7Li self-diffusion coefficients were found to increase with increasing x when compared at ...
OHKUBO TAKAHIRO, DEGUCHI KENZO, OHKI SHINOBU, SHIMIZU TADASHI, INAGAKI YAOHIRO, IWADATE YASUHIKO
Proceedings of Annual / Fall Meetings of Atomic Energy Society of Japan   2012(0)    2012
ガラス固化体の組成参考に、5成分系の模擬ガラスを作製し、粉末ガラス試料を用いたガラス溶解試験を実施した。溶解試験で得られた変成ガラスを対象に、多核固体核磁気共鳴法による解析を行い、ガラス溶解によるガラス分子構造の評価を行った。
Monden Ryusuke, Deguchi Kenzo, Ohki Shinobu, Shimizu Tadashi, Nishiyama Shin, Iwadate Yasuhiko, Ohkubo Takahiro
Proceedings of Annual / Fall Meetings of Atomic Energy Society of Japan   2012(0)    2012
ガラス固化体の組成を模擬した単純ガラスにモリブデンを添加したxMoO3-(100-x)(65.17SiO2-17.15B2O3-4.12Al2O3-13.56Na2O)ガラスを作製し、11B, 29Si MAS NMR測定および11B{23Na}REDOR NMR測定を行った。これらの固体NMR測定から得られた結果に基づいて、モリブデン添加によるガラスネットワーク構造の影響およびガラス中におけるモリブデン酸塩結晶の析出メカニズムについて考察したので報告する。
Takahiro Ohkubo, Yasuhiko Iwadate, Yu Seung Kim, Neil Henson, Yoong Kee Choe
Theoretical Chemistry Accounts   130 555-561   Oct 2011
Sulfonated poly(arylene ether ether nitrile) (m-SPAEEN) copolymers are reported to have the property of reduced water uptake compared with other hydrocarbon membranes, such as sulfonated polysulfones or polyketones, with similar ion exchange capac...
Haruaki Matsuura, Atsushi Nezu, Hiroshi Akatsuka, Sou Watanabe, Akihiko Kajinami, Yasuhiko Iwadate, Norimasa Umesaki
Progress in Nuclear Energy   53 930-934   Sep 2011
A specified technique using X-ray from synchrotron sources was developed to contribute the optimization of the condition of electrodeposition directly. For this purpose, the design of the confinement equipped with electrodes has been optimized. So...
IWADATE Yasuhiko, MATSUURA Haruaki, KAJINAMI Akihiko, TAKASE Keiichi, OHTORI Norikazu, UMESAKI Norimasa, FUJITA Reiko, MIZUGUCHI Kohji, KOFUJI Hirohide, MYOCHIN Munetaka
Electrochemistry   77(8) 736-740   Aug 2009
IWADATE Yasuhiko, HARADA Takumi, OHKUBO Takahiro, FUKUSHIMA Kazuko, MISAWA Masakatsu, FUKUNAGA Toshiharu, ITOH Keiji
Electrochemistry   77(8) 741-744   Aug 2009
Yasuhiko Iwadate, Haruaki Matsuura, Akihiko Kajinami, Keiichi Takase, Norikazu Ohtori, Norimasa Umesaki, Reiko Fujita, Kohji Mizuguchi, Hirohide Kofuji, Munetaka Myochin
Electrochemistry   77 736-740   Aug 2009
Local structure of molten lanthanum trichloride - alkaü chloride ternary systems was analyzed in terms of Raman spectroscopy and pulsed neutron diffraction in order to accelerate the realization of pyrochemical reprocessing of nuclear spent fuels....
Yasuhiko Iwadate, Takumi Harada, Takahiro Ohkubo, Kazuko Fukushima, Masakatsu Misawa, Toshiharu Fukunaga, Keiji Itoh
Electrochemistry   77 741-744   Aug 2009
The short-range structural parameters for NaNO2 and KNO 2 pure melts were determined by the time-of-flight neu-tron diffraction. The precise analyses of structural parameters obtained such as coordination number, interatomic distance, and temperat...
IWADATE Yasuhiko, MURAYOSHI Toshihisa
希土類 = Rare earths   (50) 48-49   May 2007
A. Kajinami, T. Matsuo, S. Deki, S. Deki, M. Sato, N. Umesaki, H. Matsuura, K. Takase, N. Ohtori, Y. Iwadate
Proceedings - Electrochemical Society   PV 2004-24 834-840   Dec 2006
The procedure of in-situ X-ray diffraction (XRD) measurements has been developed for the observation of elctrodeposition process in molten NaCl2CsCl salt to investigate the mechanism of pyrochemical process of nuclear fuel reprocessing system. In ...
Haruaki Matsuura, Sou Watanabe, Hiroshi Akatsuka, Tetsuo Honma, Norimasa Umesaki, Akihiko Kajinami, Keiichi Takase, Norikazu Ohtori, Yasuhiko Iwadate, Reiko Fujita, Ashok K. Adya
Proceedings - Electrochemical Society   PV 2004-24 136-140   Dec 2006
The local structure of molten 2CsCl-NaCl has been investigated for the first time by XAFS measurements carried out on SPring-8 at the K-absorption edge of Cs. The nearest-neighbor Cs+-Cl- distances and coordination numbers were found to be 3.26Å a...
Yasuhiko Iwadate, Kazuko Fukushima, Yu Ito, Norimasa Umesaki, Tetsuya Nakazawa
Journal of New Materials for Electrochemical Systems   9 323-330   Jul 2006
The local structure of LiClO4 melt has been investigated by X-ray diffraction (XRD), Roman spectroscopy, semi-empirical molecular orbital (MO) calculation (AM1-MOPAC), and ah initio MO calculation (Gaussian). The structural parameters for each ato...
Kazuko Fukushima, Yoshihiro Okamoto, Yasuhiko Iwadate, Yasuhiko Iwadate
Journal of Non-Crystalline Solids   312-314 428-432   Oct 2002
The short-range structure of molten ZnBr2-NaBr and ZnBr2-KBr has been studied by molecular dynamics simulation. The pair potential employed was a modification of the Born-Mayer-Huggins type with the Busing approximation without the dispersion term...
Y. Iwadate, T. Murayoshi, H. Matsuura, A. Kajinami, N. Umesaki, N. Sato, O. Shirai, T. Fujii, H. Yamana
KURRI Progress Report   136   Apr 2006
Yasuhiko Iwadate, Yasuhiko Iwadate, Yasuhiko Iwadate, Kazuko Fukushima, Tetsuya Nakazawa, Yoshihiro Okamoto
Journal of Non-Crystalline Solids   312-314 424-427   Oct 2002
Zn atoms in molten ZnBr2 and molten ZnBr2-2KBr were tetrahedrally coordinated by Br atoms. ZnBr4 2- units in molten ZnBr2-KBr formed clusters or a network structure by sharing a common Br atom between the units. The three-dimensional network was b...
Y. Iwadate, K. Suzuki, N. Onda, K. Fukushima, S. Watanabe, H. Matsuura, A. Kajinami, K. Takase, N. Ohtori, N. Umesaki, H. Kofuji, M. Myochin
Journal of Alloys and Compounds   408-412 248-252   Feb 2006
From the radial distribution analysis of X-ray diffraction, the nearest neighbor La-Cl distance and coordination number of Cl around La in molten LaCl3 were estimated to be about 0.28 nm and nearly equal to 6, respectively. On the other hand, acco...
S. Watanabe, R. Toyoyoshi, T. Sakamoto, Y. Okamoto, Y. Iwadate, H. Akatsuka, H. Matsuura
Physica Scripta T   T115 297-301   Dec 2005
Transmission XAFS measurements were performed on PbF2 and LiF-PbF2 at various temperatures using Pb-LIII x-ray absorption edge. Distinct phase shift of EXAFS oscillations was observed at the temperature range of superionic conductance phase transi...
IWADATE Yasuhiko, MATSUURA Haruaki, KAJINAMI Akihiko, TAKASE Keiichi, OHTORI Norikazu, UMESAKI Norimasa, KOFUJI Hirohide, MYOCHIN Munetaka
Electrochemistry   73(11) 936-938   Nov 2005
Yasuhiko Iwadate, Haruaki Matsuura, Akihiko Kajinami, Keiichi Takase, Norikazu Ohtori, Norimasa Umesaki, Hirohide Kofuji, Munetaka Myochin
Electrochemistry   73 936-938   Nov 2005
The structures of molten LaCl3 and molten CsCl-NaCl mixtures were studied by Raman spectroscopy. Ionic association in these melts was discussed according to the information of vibrational modes. Complex species of the octahedral type, LaCl6 3-, wa...
IWADATE Yasuhiko, NAKAYAMA Yuko, INADA Hiroshi, FUKUSHIMA Kazuko
Electrochemistry   73(8) 657-660   Aug 2005
Hideharu Ushida, Yasuhiko Iwadate, Takeo Hattori, Shin Nishiyama, Kazuko Fukushima, Masakatsu Misawa, Toshiharu Fukunaga
Journal of Alloys and Compounds   327(1/2) 121-126   Aug 2001
The short range structure of (1-x)B2O3-xAg2O (x=0.05-0.30) glasses was investigated by time-of-flight neutron scattering experiments. Radial distribution analyses were applied to extract the structural information, but the structural parameters fo...
IWADATE Yasuhiko, MATSUURA Haruaki, KAJINAMI Akihiko, TAKASE Keiichi, OHTORI Norikazu, UMESAKI Norimasa, KOFUJI Hirohide, MYOCHIN Munetaka
Electrochemistry   73(8) 710-714   Aug 2005
TAKASE Keiichi, MATSUURA Haruaki, KAJINAMI Akihiko, IWADATE Yasuhiko, KOFUJI Hirohide, MYOCHIN Munetaka, UMESAKI Norimasa, OHTORI Norikazu
Electrochemistry   73(8) 748-750   Aug 2005
Yasuhiko Iwadate, Haruaki Matsuura, Akihiko Kajlnami, Keiichi Takase, Norikazu Ohtori, Norimasa Umesaki, Hirohide Kofuji, Munetaka Myochin
Electrochemistry   73 710-714   Aug 2005
The local structures of molten LaCl3 and solid LaOCl at elevated temperatures were deduced from radial distribution analyses through La-L III absorption-edge XAFS technique. The nearest neighbor La-Cl distance and the coordination number of Cl aro...
Keiichi Takase, Haruaki Matsuura, Akihiko Kajinami, Yasuhiko Iwadate, Hirohide Kofuji, Munetaka Myochin, Norimasa Umesaki, Norikazu Ohtori
Electrochemistry   73 748-750   Aug 2005
We performed trial MD simulations for molten (Na-2Cs)Cl containing 10 wt% of UO2 2+ at 1100 K. In order to incorporate different function forms between alkali halides and UO2, the Tosi-Fumi potentials used for the former were converted to the func...
K. Fukushima, H. Inada, Y. Nakayama, Y. Iwadate
Journal of Alloys and Compounds   315(1/2) 129-133   Feb 2001
The molar conductivities of molten ZnBr2-NaBr and ZnBr2-KBr systems are evaluated. The analysis used the data of molar volume and electrical conductivity which are measured by dilatometry and a conventional alternating current technique, respectiv...
Yasuhiko Iwadate, Yuko Nakayama, Hiroshi Inada, Kazuko Fukushima
Electrochemistry   73 657-660   Aug 2005
Molar conductivities of molten PbB2-NaBr and PbBr 2-KBr systems were evaluated using the data of molar volume and electrical conductivity which were measured by dilatometry and a conventional a.c. technique, respectively. The molar conductivities ...
Y. Iwadate, Y. Seki, S. Yamashita, K. Fukushima
Journal of Alloys and Compounds   397 226-230   Jul 2005
Raman spectra of molten PbBr2-NaBr and PbBr2-KBr systems showed the strongly polarized bands at about 150 cm-1. These Raman bands were identified as the totally symmetric stretching vibration modes of tetrahedral species PbBr4 2- by consulting wit...
MURAYOSHI T., FUKUSHIMA K., IWADATE Y.
希土類 = Rare earths   46 168-169   May 2005
Yasuhiko Iwadate, Takeshi Mori, Takeo Hattori, Shin Nishiyama, Kazuko Fukushima, Norimasa Umesaki, Ryuichi Akagi, Katsumi Handa, Norikazu Ohtori, Tetsuya Nakazawa, Akira Iwamoto
Journal of Alloys and Compounds   311(2) 153-158   Oct 2000
The short-range structure of K2O-9TeO2 and K2O-4TeO2 in amorphous states such as glass and melt has been investigated by X-ray diffraction (XRD) and semi-empirical molecular orbital calculation (AM1-MOPAC method). The structure of amorphous alkali...
Yasuhiko Iwadate, Mineta Suzuki, Takeo Hattori, Kazuko Fukushima, Shin Nishiyama, Masakatsu Misawa, Toshiharu Fukunaga, Keiji Itoh
Journal of Alloys and Compounds   389 229-233   Mar 2005
The local structure of Ag2O-TeO2 glasses was studied by time-of-flight pulsed neutron diffraction (TOF-PND) and Raman spectroscopy. The results of Raman spectroscopy indicated that TeO4 trigonal bipyramidal units (tbp) were converted to TeO3 trigo...
Yasuhiko Iwadate, Hidetaka Kenmotsu, Takeo Hattori, Shin Nishiyama, Kazuko Fukushima, Norimasa Umesaki, Tetsuya Nakazawa, Kenji Noda
Journal of Alloys and Compounds   305(1/2) 130-135   Jun 2000
Structural analyses of amorphous LiCl-Li2O-TeO2 were made by X-ray diffraction. The basic structure of the tellurite glasses consisted of the TeO4 trigonal bipyramids and the TeO3 trigonal pyramids. The resulting structure was in agreement with th...
Y. Iwadate, Y. Seki, K. Fukushima, M. Misawa, T. Fukunaga, K. Itoh, T. Nakazawa, Y. Okamoto, H. Matsuura, A. Kajinami, N. Ohtori, N. Umesaki
Journal of Physics and Chemistry of Solids   66 433-438   Feb 2005
According to the radial distribution analysis of PbCl2 melt through pulsed neutron diffraction (PND), the Cl-coordination numbers around Pb were found to be about 4, corresponding to the peak at r=2.84 Å in the correlation function G(r), and to be...
Kazuko Fukushima, Yoshihiro Okamoto, Yasuhiko Iwadate
Journal of Physics and Chemistry of Solids   66 414-417   Feb 2005
The short-range structure of ZnBr2-ZnCl2 melts has been deduced from molecular dynamics (MD) simulation by using the experimental interference function Q·i(Q). The pair potential employed was the modifications of the Born-Mayer-Huggins-type with t...
S. Watanabe, R. Toyoyoshi, T. Sakamoto, Y. Okamoto, Y. Iwadate, H. Akatsuka, H. Matsuura
Journal of Physics and Chemistry of Solids   66 402-405   Feb 2005
In this work, X-ray Absorption Fine Structure (XAFS) measurements of PbF2 and LiF-PbF2 (PbF2: 60% mol) were carried out with Pb-LIII X-ray Absorption edge to investigate local structure of molten LiF-PbF2 which we have proposed as one of the candi...
Y. Okamoto, Y. Iwadate, K. Fukushima, H. Matsuura, K. Minato
Journal of Physics and Chemistry of Solids   66 452-455   Feb 2005
The structure of molten PbCl2 was investigated by using high temperature X-ray diffraction(XRD) and X-ray absorption fine structure (XAFS) analysis techniques. It is concluded from the Fourier transformation and Debye scattering analyses of the XR...
Hideharu Ushida, Yasuhiko Iwadate, Takeo Hattori, Shin Nishiyama, Kazuko Fukushima, Yasuhisa Ikeda, Makoto Yamaguchi, Masakatsu Misawa, Toshiharu Fukunaga, Tetsuya Nakazawa, Shiro Jitsukawa
Journal of Alloys and Compounds   377 167-173   Sep 2004
The structure of (1-x)B2O3-xPbO (x=0.20, 0.30, 0.40) glasses and (0.98-x)B2O3-xPbO-0.02PbBr2 (x=0.18, 0.28, 0.38) glasses was studied by time-of-flight pulsed neutron diffraction. The structural parameters for each atomic pair were optimized in th...
Y. Iwadate, K. Fukushima, Y. Seki, K. Itoh, T. Fukunaga, M. Misawa, H. Matsuura, A. Kajinami, N. Ohtori, N. Umesaki, H. Kofuji, M. Myochin
Science and Technology of Advanced Materials   5 683-687   Sep 2004
Although the melt structure of glass-forming ZnCl2 has so far been well studied, there exists quite little information on the structural change due to anion-substitution. In the present work, the short-range structure of ZnCl2-ZnBr2 mixture melts ...
Science and Technology of Advanced Materials   5[5-6], 683-687    2004
K. Shirao, T. Hattori, S. Nishiyama, K. Fukushima, Y. Iwadate, M. Misawa, T. Fukunaga, T. Nakazawa, K. Noda
Journal of Physics and Chemistry of Solids   60 1453-1456   Sep 1999
The short range structure analysis of (1 - x)As2Se3-xAg2Se (x = 0.05-0.30) glasses were studied by the time-of-flight (TOF) neutron diffraction method, and the effects of Ag2Se addition on the network structure of AsSe3 trigonal pyramid were inves...
H. Kenmotsu, T. Hattori, S. Nishiyama, K. Fukushima, Y. Iwadate, M. Misawa, T. Fukunaga, T. Nakazawa, K. Noda
Journal of Physics and Chemistry of Solids   60(8/9) 1461-1464   Sep 1999
The short range structure of (1 - x)B2O3-xRb2O (x = 0.05-0.30) glasses was investigated to study by time-of-flight neutron scattering experiments using the high intensity total scattering spectrometer (HIT). In each correlation function of G(r) cu...
Yoshihiro Okamoto, Kazuko Fukushima, Yasuhiko Iwadate
Journal of Non-Crystalline Solids   312-314, 450-453 450-453   Oct 2002
The local structure of molten ZnBr2 was investigated by X-ray absorption fine structure measurements for both Zn and Br above their K-absorption edges at 723 K. The results show that a tetrahedral coordination (ZnBr4)2- exists and most coordinates...
Y. Iwadate, T. Hattori, S. Nishiyama, K. Fukushima, Y. Mochizuki, M. Misawa, T. Fukunaga
Journal of Physics and Chemistry of Solids   60(8/9) 1447-1451   Sep 1999
The pair distribution functions G(r)'s of As2S3 and As2Se3 glasses were obtained from the structure factors S(Q)'s. The structural parameters were refined by applying the correlation method in the (Q, Q·i(Q) space. Although the structural paramete...
H. Ushida, Y. Iwadate, K. Fukushima, M. Misawa, T. Fukunaga, T. Nakazawa, A. Iwamoto
Journal of Molecular Liquids   100 183-197   Sep 2002
The short range structure of NaClO3 and KClO3 melts was investigated by time-of-flight neutron diffraction, Raman spectroscopy, and molecular orbital calculation. The structural parameters for each atomic pair were optimized in the Q-space, and th...
Kazuya Shirao, Yasuhiko Fujii, Junji Tominaga, Kazuko Fukushima, Yasuhiko Iwadate
Journal of Alloys and Compounds   339 309-316   Jun 2002
The refractive index and molar volume of each molten chloride were measured by goniometry and dilatometry, respectively. The refractive indexes were represented as polynomial functions of both temperature and wavelength in empirical formulas by a ...
SUKUR Edi, HATTORI Takeo, IWADATE Yasuhiko, NISHIYAMA Shin
Journal of the Chemical Society of Japan,chemistry and industrial chemistry   2002(1) 19-25   Jan 2002
IWADATE Yasuhiko, HATTORI Takeo, NISHIYAMA Shin, FUKUSHIMA Kazuko, SUGAWARA Yoshie, NAKAZAWA Tetsuya, NODA Kenji, TATSUMISAGO Masahiro, UMESAKI Norimasa
Nippon kagaku zassi   (7) 460-464   Jul 1998
Since Li2O-TeO2 glasses have unique properties such as high densities, high refractive indexes, large dielectric constants and transmittance in a wide infrared wavelength region, much scientific attention has been focused on ...
Y. Iwadate, H. Kenmotsu, T. Mori, K. Fukushima, M. Misawa, T. Fukunaga
Journal of Non-Crystalline Solids   293-295 586-594   Nov 2001
Structural analyses of (1-x)ZnBr2-xKBr melts were made by time-of-flight pulsed neutron diffraction. The interatomic distance rij of the nearest neighbor Zn-Br pair was estimated at about 2.4 Å which was shorter than the sum of ionic radii 2.56 Å,...
Norikazu Ohtori, Keiichi Takase, Isao Akiyama, Yoshihiro Suzuki, Katsumi Handa, Ichiro Sakai, Yasuhiko Iwadate, Toshiharu Fukunaga, Norimasa Umesaki
Journal of Non-Crystalline Solids   293-295 136-145   Nov 2001
The structure of vitreous MO · nB2O3 (M = Ca and Ba; n = 2, 3 and 4) has been studied by pulsed neutron diffraction measurement with the help of molecular dynamics (MD) simulation. The first and second peaks assigned to the nearest-neighbor B-O an...
Journal of Non-Crystalline Solids   293-295[3], 586-594    2001
Hideki Yokota, Kazuko Fukushima, Yasuhiko Iwadate
Journal of Alloys and Compounds   239(2) 114-116   Jun 1996
In this study, Raman spectra of molten ZnBr2-KBr systems were measured at different compositions and temperatures to ensure the existence of tetrahedral ZnBr2- 4 structural units. Each spectrum was deconvoluted in terms of the Gaussian function. T...
Pulsed Neutron Diffraction and X-ray Diffraction Study on the Short Range Structure of Na2O-TeO2 Glasses and Melts
Journal of Physical Society of Japan   70(Suppl. A) 389-391   2001
Ionic Species and Linkage in Ligand-substituted ZnCl2-ZnBr2 Melts
Journal of Physical Society of Japan   70(Suppl. A) 359-361   2001
Structural Analysis of Molten NaClO3 and KClO3 by T-O-F Pulsed Neutron Diffraction
Journal of Physical Society of Japan   70(Suppl. A) 353-355   2001
N. Ohtori, K. Takase, I. Akiyama, K. Handa, Y. Iwadate, N. Umesaki
Physics and Chemistry of Glasses   41 369-372   Dec 2000
Molecular dynamics (MD) simulations have been performed for alkaline earth borate glasses using purely ionic potential functions. We present some results concerning the pair correlation functions, g(r), the running coordination numbers, n(r), the ...
TAKESHIMA Yoshiyuki, FUKUSHIMA Kazuko, IWADATE Yasuhiko
希土類 = Rare earths   (36) 84-85   May 2000
MD Study of the Short Range Structure of RO・┣DBx(/)-┫DBB2O3 Glasses : R=Mg, Ca, Sr and Ba ; ┣DBx(/)-┫DB=1, 2, 3 and 4
Physics and Chemistry of Glasses   41(6) 369-372   2000
K. Fukushima, T. Ikumi, J. Mochinaga, R. Takagi, M. Gaune-Escard, Y. Iwadate
Journal of Alloys and Compounds   229(2) 274-279   Nov 1995
Molar conductivities (Λ) of molten ErCl3NaCl and ErCl3KCl systems were evaluated using the data of molar volume, Vm, and conductivity, κ{script}, which were measured as a function of the mole fraction of ErCl3 and temperature, by dilatometry and a...
Yasuhiko Iwadate, Kazuko Fukushima
Journal of Chemical Physics   103(14) 6300-6302   Dec 1995
The electronic polarizability of a fluoride ion was evaluated from the refractive indexes extrapolated to infinite wavelength and the molar volumes of molten eutectic LiF-NaF-KF, and compared with the data previously reported. © 1995 American Inst...
Yasuhiko Iwadate, Norikazu Okako, Yasuyuki Koyama, Hirokazu Kubo, Kazuko Fukushima
Journal of Molecular Liquids   65-66 369-372   Jan 1995
Precise analyses of liquid structures of pure CeCl3 and ErCl3 were made by consulting the bond lengths in crystals and the volume changes on melting, allowing for octahedral geometry around the lanthanide atoms and the corner-sharing linkage of oc...
Yasuhiko Iwadate, Kazuko Fukushima, Ryuzo Takagi, Marcelle Gaune-Escard
Electrochemistry   67 553-557   Dec 1999
The short range structure of Na3ErCl6 melt at 973 K and K3ErCl6 melt at 1053 K was investigated by X-ray diffraction. The nearest neighbor distance of Er3+-Cl- and the coordination number of Cl- around Er3+ in Na3ErCl6 melt, for instance, were est...
Y. Iwadate, T. Hattori, S. Nishiyama, K. Fukushima
Journal of Materials Science Letters   14(2) 85-87   Jan 1995
Yasuhiko Iwadate, Kazuya Shirao, Kazuko Fukushima
Journal of Alloys and Compounds   284 89-91   Dec 1999
The refractive indexes and the molar volumes of molten SmCl3 were measured by goniometry and dilatometry, respectively. The electronic polarizability of a Sm3+ ion was estimated from these data to be 1.14×10-30m3 according to the Clausius-Mossotti...
M. Gaune-Escard, Y. Koyama, R. Takagi, K. Fukushima, Y. Iwadate
Journal of Molecular Liquids   83 105-110   Dec 1999
Y. Iwadate, H. Yamoto, K. Fukushima, R. Takagi
Journal of Molecular Liquids   83 41-49   Dec 1999
The short range structure of molten SmCl3-NaCl system at different compositions and temperatures was studied by the conventional molecular dynamics simulation (MD). According to this work, the octahedral SmCl6 3- complex anions were found to exist...
Kazuko Fukushima, Hiromitsu Yamoto, Yasuhiko Iwadate
Journal of Alloys and Compounds   290 114-118   Dec 1999
Raman spectra of molten SmCl3-ACl systems (A = Li, Na, K) were measured at different compositions and temperatures. The spectra showed polarized peaks centered at about 256 cm-1 in the whole range of concentration and depolarized peaks at about 12...
XAFS Studies of Alkaline-Earth Borate Glasses
Japanese Journal of Applied Physics   38(Suppl.38-1) 148-151   1999
服部豪夫, 岩舘泰彦, 富川孝幸
日本セラミックス協会学術論文誌   98(1) 117-119   Jan 1990
GaAs was thermally analyzed in air using a TG-DTA apparatus prior to the densification. Result showed that GaAs was oxidized at 550℃. Then, normal sintering at 800℃ for 2 h was conducted under N_2 atmosphere. The sintered body did not density with...
Cation Structure in Binary Potassium Borate Glasses
Japanese Journal of Applied Physics   38(Suppl.38-1) 140-143   1999
Molar Volume of Molten EuCl2 : Estimation and Experimental
Journal of Molecular Liquids   83(1-3) 105-110   1999
T. Hattori, S. Nishiyama, Y. Kishi, Y. Iwadate
Journal of Materials Science Letters   12 883-885   Jan 1993
K. Igarashi, K. Tajiri, T. Asahina, M. Kosaka, Y. Iwadate, J. Mochinaga
Journal of Materials Science   28(10) 2774-2778   Jan 1993
The hydration structure of calcium nitrate tetrahydrate, Ca(NO3)2 · 4.1 H2O, melt at 328 K has been investigated by X-ray scattering and correlation method. Analysis of the radial distribution function and model fitting revealed that in the hydrat...
Molecular Dynamics Study of Ionic Aggregation in Molten SmCl3-NaCl System
Journal of Molecular Liquids   83(1-3) 41-49   1999

Research Grants & Projects

 
Study on Structure and Physical Property of Ionic Melt
Basic Science Research Program
Structural Analysis of Glasses
Basic Science Research Program
Solid State Sciences in Ceramics
Basic Science Research Program
Irradiation effect of heavy ions and γ-rays on inorganic compounds
Preparation of Rare Earth Halides