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Sc
O
Shimoyama, Tomotaka*; Tojo, Takeo*; Kawaji, Hitoshi*; Atake, Toru*; Fukazawa, Hiroshi; Igawa, Naoki
Solid State Ionics, 180(6-8), p.560 - 562, 2009/05
Times Cited Count：6 Percentile：27.91(Chemistry, Physical)The neutron diffraction of BaZrScO with and without proton were measured and analyzed by Rietveld method and Maximum Entropy Method. We found that the location of proton is 12
site near oxygen ion. The heat capacity of sample with proton is larger than that without proton. This difference is discussed in term of the changes of the crystal structure and lattice vibrations due to the dissolution of proton.
Ca
Nb
O
Shimoyama, Tomotaka*; Tojo, Takeo*; Kawaji, Hitoshi*; Atake, Toru*; Igawa, Naoki; Ishii, Yoshinobu*
Solid State Ionics, 179(7-8), p.231 - 235, 2008/04
Times Cited Count：15 Percentile：52.78(Chemistry, Physical)The neutron diffraction study was carried out to determine the location of proton conducting mixed perovskite-type oxide BaCaNbO at 300K. The obtained data have been analyzed by the Rietveld method and the maximum entropy method. The crystal structure of the sample is refined on the basis of the cubic structure with the space group 
-3
. We found that oxide ion locates at 24
site and deuterium 96
site, respectively. The distance between oxide ion and deuterium sites is about 0.72
, which is shorter than the normal distance of OD group. The oxygen in OD group is shifted from 24 site slightly toward the opposite side of deuterium and the deuterium is shifted to the Ca/Nb mixed site.
CaNbOShimoyama, Tomotaka*; Sagiya, Jun*; Tojo, Takeo*; Kawaji, Hitoshi*; Atake, Toru*; Igawa, Naoki; Ishii, Yoshinobu
Proceedings of 10th Asian Conference on Solid State Ionics, p.201 - 205, 2006/00
no abstracts in English
Igawa, Naoki; Ishii, Yoshinobu; Hoshikawa, Akinori; Yamauchi, Hiroki; Shimoyama, Tomotaka
JAERI-Tech 2004-067, 23 Pages, 2004/11
JAERI-Tech-2004-067.pdf:5.88MB
We synthesized methane hydrate using fine grain ice. The amount of released-gas volume was the same as calculated one for ideal methane hydrate within experimental precision. The neutron diffraction measurement was conducted by means of a high-resolution powder diffractometer (HRPD) installed at JRR-3. No reflection line from the impurities and ice was found in the diffraction pattern. Therefore, the synthesized methane hydrate proved to be very high quality. We also showed the scattering density map of this sample using Rietveld analysis and the maximum entropy method (MEM).
Shimoyama, Tomotaka*; Tojo, Takeo*; Kawaji, Hitoshi*; Atake, Toru*; Fukazawa, Hiroshi; Igawa, Naoki
no journal, ,
Proton conductor BaZrScO was synthesized by a solid state reaction method. Neutron diffraction experiments were performed for dried and D
O dissolute samples at 10 K. The observed data were analyzed by Rietveld method and Maximum Entropy method. It has been clarified that the deuterium exits at 12 site. It is founded that the distance between oxide ion site and deuterium site is shorter than the normal distance of O-D.
CaNbOShimoyama, Tomotaka*; Tojo, Takeo*; Kawaji, Hitoshi*; Atake, Toru*; Igawa, Naoki; Ishii, Yoshinobu
no journal, ,
no abstracts in English
ScOShimoyama, Tomotaka*; Tojo, Takeo*; Kawaji, Hitoshi*; Atake, Toru*; Fukazawa, Hiroshi; Igawa, Naoki
no journal, ,
Sc doped BaZrO is one of the canditated materials for solid state proton conductors in the middle temeprature range because of its high proton conducticivity and excellent chemical stability under the humidity. This presentation makes discusion on the crystal structure of BaZrScO with DO using Rietveld method and Maximum Entropy method.
