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Nagai, Takayuki; Kobayashi, Hidekazu; Shimamura, Keisuke; Oyama, Koichi; Sasage, Kenichi; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamanaka, Keisuke*; Ota, Toshiaki*
JAEA-Research 2018-005, 72 Pages, 2018/09
JAEA-Research-2018-005.pdf:28.2MB
Addition of radioactive waste to a borosilicate glass frit affects the local structures of glass-forming elements and waste elements in a waste glass produced in a vitrification process. In this study, simulated waste glass samples were prepared from borosilicate glass frit including phosphorus pentaoxide, and we investigated local structures of sodium (Na), boron (B), and waste elements in these glass samples by using synchrotron XAFS measurements in soft and hard X ray region.
Okamoto, Yoshihiro; Nagai, Takayuki; Kaneko, Koji; Motokawa, Ryuhei; Haga, Yoshinori; Yamanaka, Keisuke*; Ota, Toshiaki*
2017-Nendo Seika Kokaigata Riyo Seika Hokokusho (Ritsumeikan Daigaku SR Senta), p.33 - 36, 2018/00
The high-level radioactive waste solution which generated from a spent nuclear fuel reprocessing process are mixed with a borosilicate glass frit in a vitrification process, and a chemical stable glass solidified body is produced. To understand local structure of light elements included in a glass solidified body, we carried out a B K-edge XANES measurement of raw glass frits and simulated radioactive waste glasses. As a result of this estimation of boron local structure in glass samples, it was found that the sp
type boron (BO
) percentage increases and the sp
type (BO
) percentage by increasing the sodium content in glass frits.
Nagai, Takayuki; Kobayashi, Hidekazu; Sasage, Kenichi; Ayame, Yasuo; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamanaka, Keisuke*; Ota, Toshiaki*
JAEA-Research 2017-005, 54 Pages, 2017/06
JAEA-Research-2017-005.pdf:16.17MB
Addition of radioactive waste to a borosilicate frit affects the local structures of boron (B) and waste elements in a waste glass. Synchrotron XAFS measurement was applied to investigate the local structural changes by using simulated waste borosilicate glass samples. Following results were obtained by the B K-edge XAFS analysis. It was confirmed that B K-edge XAFS analysis enables us to discriminate sp type boron (BO) from sp type boron (BO). Addition of waste elements to a glass frit increases the percentage of BO and decreases that of BO. By decreasing the SiO
/AlO ratio or increasing the (SiO+BO)/AlO ratio in the glass composition, the BO percentage increases and the BO percentage decreases. Addition of PO
decreases the BO percentage and increases the BO percentage. Following results were obtained from XAFS measurement of the waste elements. Cerium (Ce) valence is more reduced with the increase of the BO content. Addition of PO has a tendency to reduce the Ce valence and to enhance deposition of Zr oxide. Deposition of ruthenium compounds separated from glass phase can not be improved by changing the BO content. This study was performed as a part of the project, "Improvement of vitrification process of high-level radioactive liquid wastes" on the foundation business of the Agency for Natural Resources and Energy.
Suzuki, Tetsuya*; Yamanaka, Keisuke*; Ishino, Mayuko*; Shinohara, Yasuhiro*; Nagai, Kensuke*; Tsuru, Eiji*; Xu, P. G.
Tetsu To Hagane, 98(6), p.262 - 266, 2012/06
Osawa, Hideaki; Ota, Kunio; Hama, Katsuhiro; Sawada, Atsushi; Takeuchi, Shinji; Amano, Kenji; Saegusa, Hiromitsu; Matsuoka, Toshiyuki; Miyamoto, Tetsuo; Toyoda, Gakuji; et al.
JAEA-Research 2008-085, 742 Pages, 2008/11
JAEA-Research-2008-085-1.pdf:26.22MBJAEA-Research-2008-085-2.pdf:16.64MBJAEA-Research-2008-085-3.pdf:28.27MB
This report shows the results the project for the establishment of comprehensive site characterization technology, entrusted from Natural Resources and Energy Agency, Ministry of Economy, Trade and Industry Natural Resources and Energy Agency in 2007.
Shimada, Yoshinori*; Nishimura, Hiroaki*; Nakai, Mitsuo*; Hashimoto, Kazuhisa*; Yamaura, Michiteru*; Tao, Y.*; Shigemori, Keisuke*; Okuno, Tomoharu*; Nishihara, Katsunobu*; Kawamura, Toru*; et al.
Applied Physics Letters, 86(5), p.051501_1 - 051501_3, 2005/01
Times Cited Count：113 Percentile：94.26(Physics, Applied)no abstracts in English
Saegusa, Hiromitsu; Ota, Kunio; Niizato, Tadafumi; Amano, Kenji; Yamanaka, Yoshiaki; Maekawa, Keisuke; Kunimaru, Takanori; Hama, Katsuhiro
no journal, ,
no abstracts in English
Yamanaka, Takahiro*; Fujita, Satoshi*; Minagawa, Keisuke*; Kanaeda, Shingo*; Kitamura, Seiji; Watakabe, Tomoyoshi
no journal, ,
no abstracts in English
Xu, P. G.; Suzuki, Tetsuya*; Yamanaka, Keisuke*; Akita, Koichi
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Suzuki, Tetsuya*; Yamanaka, Keisuke*; Ishino, Mayuko*; Xu, P. G.; Suzuki, Hiroshi
no journal, ,
no abstracts in English
Suzuki, Tetsuya*; Yamanaka, Keisuke*; Nagai, Kensuke*; Tsuru, Eiji*; Xu, P. G.; Suzuki, Hiroshi
no journal, ,
no abstracts in English
Yamanaka, Keisuke*; Nagai, Takayuki; Ota, Toshiaki*
no journal, ,
For understanding the fundamental knowledge in the vitrification process of radioactive waste, the local structure of boron of simulated waste glass was investigated by using the XAFS measurement in BL-11 of Ritsumeikan University SR Center.
Nagai, Takayuki; Okamoto, Yoshihiro; Yamanaka, Keisuke*; Ota, Toshiaki*
no journal, ,
no abstracts in English
Nagai, Takayuki; Kobayashi, Hidekazu; Okamoto, Yoshihiro; Yamanaka, Keisuke*; Ota, Toshiaki*
no journal, ,
no abstracts in English
Nagai, Takayuki; Okamoto, Yoshihiro; Kaneko, Koji; Motokawa, Ryuhei; Haga, Yoshinori; Yamagishi, Hirona*; Yamanaka, Keisuke*; Ota, Toshiaki*
no journal, ,
no abstracts in English
