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Yamagishi, Isao; Nagaishi, Ryuji; Kato, Chiaki; Morita, Keisuke; Terada, Atsuhiko; Kamiji, Yu; Hino, Ryutaro; Sato, Hiroyuki; Nishihara, Kenji; Tsubata, Yasuhiro; et al.
Journal of Nuclear Science and Technology, 51(7-8), p.1044 - 1053, 2014/07
Times Cited Count：19 Percentile：78.38(Nuclear Science & Technology)For safe storage of zeolite wastes generated by treatment of radioactive saline water at the Fukushima Daiichi Nuclear Power Station, properties of the Herschelite adsorbent were studied and its adsorption vessel was evaluated for hydrogen production and corrosion. Hydrogen production depends on its water level and dissolved species because hydrogen is oxidized by radicals in water. It is possible to evaluate hydrogen production rate in Herschelite submerged in seawater or pure water by taking into account of the depth effect of the water. The reference vessel of decay heat 504 W with or without residual pure water was evaluated for the hydrogen concentration by thermal hydraulic analysis using obtained fundamental properties. Maximum hydrogen concentration was below the lower explosive limit (4 %). The steady-state corrosion potential of a stainless steel 316L increased with absorbed dose rate but its increase was repressed by the presence of Herschelite. At 750 Gy/h and 
60
C which were values evaluated at the bottom of the vessel of 504 W, the localized corrosion of SUS316L contacted with Herschelite would not immediately occur under 20,000 ppm of Cl
concentration.
using resonant X-ray emission spectroscopy at the Ba-L and Ti K absorption edgesYoshii, Kenji; Yoneda, Yasuhiro; Jarrige, I.*; Fukuda, Tatsuo; Nishihata, Yasuo; Suzuki, Chikashi; Ito, Yoshiaki*; Terashima, Takahito*; Yoshikado, Shinzo*; Fukushima, Sei*
Journal of Physics and Chemistry of Solids, 75(3), p.339 - 343, 2014/03
Times Cited Count：10 Percentile：41.9(Chemistry, Multidisciplinary)We have studied the electronic properties of ferroelectric BaTiO using two complementary bulk-sensitive spectroscopic probes, resonant X-ray emission spectroscopy (RXES) and X-ray absorption spectroscopy in the partial fluorescence mode (PFY-XAS). Contrary to a previous study, we found no temperature change of a PFY-XAS spectrum at the Ba L edge between room temperature and 150C. This result is not supportive of the possible presence of the displacement around Ba
at the Curie temperature. RXES spectra were measured at the Ti K edge for BaTiO, along with SrTiO and La-doped metallic SrTiO. The photon energy of the emission peak is found to be nearly constant throughout the absorption edge for all three compounds. We deduce the Ti 3d states to have a delocalized character, in contrast with the Ba 5d states, a property which is consistent with the proposed scenario of the formation of electric dipoles in BaTiO.
Yamagishi, Isao; Nagaishi, Ryuji; Terada, Atsuhiko; Kamiji, Yu; Kato, Chiaki; Morita, Keisuke; Nishihara, Kenji; Tsubata, Yasuhiro; Ji, W.*; Fukushima, Hisashi*; et al.
IAEA-CN-211 (Internet), 5 Pages, 2013/01
Since the accident at Fukushima Daiichi Nuclear Power Station, a large amount of radioactive contaminated water has been generated to cool damaged reactor cores. Adsorption of cesium with zeolite-like media was employed for treatment of this contaminated saline water. As spent zeolite media are highly radioactive, their safe storage is a pressing issue. Japan Atomic Energy Agency has extensively conducted R&D on the management of secondary wastes produced by the operation of the treatment system. Subjects on the safe storage of spent zeolites include the analysis of their characteristics and the evaluation of effectiveness of the present safety measures in consideration of decay heat emission and hydrogen generation by water radiolysis as well as durability of vessels exposed to saline. Preliminary results obtained are described in the present paper.
and BaSO
; A Resonant X-ray emission study at the Ba-L edgeYoshii, Kenji; Jarrige, I.; Suzuki, Chikashi; Matsumura, Daiju; Nishihata, Yasuo; Yoneda, Yasuhiro; Fukuda, Tatsuo; Tamura, Kazuhisa; Ito, Yoshiaki*; Mukoyama, Takeshi*; et al.
Journal of Physics and Chemistry of Solids, 73(9), p.1106 - 1110, 2012/09
Times Cited Count：11 Percentile：44.07(Chemistry, Multidisciplinary)We have directly probed the Ba 5d states in the ferroelectric barium titanate BaTiO using resonant X-ray emission spectroscopy (RXES) and X-ray absorption spectroscopy in the partial fluorescence mode (PFY-XAS) at the Ba-L edge. The results are compared with those of the non-ferroelectric BaSO. While the RXES spectra point to a localized character for the Ba 5d states in both compounds, the main peak of the PFY-XAS spectrum, corresponding to the dipolar transitions from 2p to 5d, is found to be significantly broader for BaTiO than for BaSO. On the basis of band structure calculations, this broadening is ascribed to strong hybridization between the unoccupied Ba 5d and O 2p states in the ferroelectric. This suggests that the hybridization between the conduction states of the Ba and O
ions, and not only Ti
and O, plays a central role in determining the electronic structure of BaTiO.
edge in BaTiOYoshii, Kenji; Jarrige, I.; Matsumura, Daiju; Nishihata, Yasuo; Suzuki, Chikashi; Ito, Yoshiaki*; Mukoyama, Takeshi*; Tochio, Tatsunori*; Shinotsuka, Hiroshi*; Fukushima, Sei*
Japanese Journal of Applied Physics, 50(9), p.09NE03_1 - 09NE03_4, 2011/09
Times Cited Count：2 Percentile：9.73(Physics, Applied)Resonant X-ray inelastic scattering experiments have been performed at the Ba-L edge in ferroelectric BaTiO using synchrotron radiation at the BL15XU of SPring-8. An X-ray absorption spectrum of this material was found to be broader than non-ferroelectric BaSO. Molecular orbital calculations showed the formation of Ba-O bands in BaTiO, suggesting an important role of the Ba-O hybridization in the ferroelectric transition of this material. X-ray emission spectra at the edge showed a localized character of Ba-5d orbitals in BaTiO in spite of the hybridization with O-3p. A few possible applications of the measurement will be also discussed.
Fukushima, Isao; Takeda, Seietsu; Yamazaki, Shinichi; Ishikawa, Hirohisa
JNC TN1400 2003-014, 65 Pages, 2004/02
JNC-TN1400-2003-014.pdf:47.43MB
none
Onodera, Seiji; Sugawara, Susumu; Kobayashi, Heigo; Haga, Koichi; Fukushima, Susumu*; Shichiji,Isamu*; Ono, Akio
JAERI-Tech 2002-070, 77 Pages, 2002/09
JAERI-Tech-2002-070.pdf:8.74MB
no abstracts in English
Fukushima, Masami*; Tatsumi, Kenji*; Nagao, Seiya
Environmental Science & Technology, 35(18), p.3683 - 3690, 2001/09
Times Cited Count：135 Percentile：92.77(Engineering, Environmental)no abstracts in English
Oikawa, Tetsukuni; Fukushima, Seiichiro*; Takase, Hidekazu*; Uchiyama, Tomoaki*; Muramatsu, Ken
Transactions of 16th International Conference on Structural Mechanics in Reactor Technology (SMiRT-16) (CD-ROM), 8 Pages, 2001/08
no abstracts in English
Kawatsuma, Shinji; Funabashi, Hideyuki; Yagi, Naoto; Kudo, Kenji; Tsujimura, Seiichi; Fukushima, Tadashi
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Kunimaru, Takanori; Fukushima, Tatsuo; Takeda, Seietsu
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Ji, W.*; Fukushima, Hisashi*; Sato, Seichi*; Kozaki, Tamotsu*; Yamagishi, Isao; Nishihara, Kenji
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Fukushima, Hisashi*; Ji, W.*; Sato, Seichi*; Kozaki, Tamotsu*; Yamagishi, Isao; Nishihara, Kenji
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and BaSO; A Resonant X-ray emission study at the Ba-L edgeYoshii, Kenji; Jarrige, I.; Matsumura, Daiju; Nishihata, Yasuo; Suzuki, Chikashi; Ito, Yoshiaki*; Mukoyama, Takeshi*; Tochio, Tatsunori*; Shinotsuka, Hiroshi*; Fukushima, Sei*
no journal, ,
We have directly probed the Ba 5d states in the ferroelectric BaTiO by resonant X-ray emission spectroscopy (RXES) and X-ray absorption spectroscopy in the partial fluorescence mode (PFY-XAS) at the Ba-L edge. The results are compared with those of the non-ferroelectric barium sulfate BaSO. While the RXES spectra point to a localized character for the Ba 5d states in both compounds, the main peak of the PFY-XAS spectrum is found to be significantly broader for BaTiO than for BaSO. On the basis of band structure calculations, this broadening is ascribed to strong hybridization between the unoccupied Ba 5d and O 2p states in the ferroelectric phase. This suggests that the hybridization between the conduction states of the Ba and O ions, and not only Ti and O, plays some roles in the occurrence of ferroelectricity in BaTiO.
Yamagishi, Akihiko*; Yokobori, Shinichi*; Hashimoto, Hirofumi*; Yano, Hajime*; Imai, Eiichi*; Okudaira, Kyoko*; Kawai, Hideyuki*; Kobayashi, Kensei*; Tabata, Makoto*; Nakagawa, Kazumichi*; et al.
no journal, ,
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Ji, W.*; Fukushima, Hisashi*; Sato, Seichi*; Watanabe, Naoko*; Kozaki, Tamotsu*; Yamagishi, Isao; Nishihara, Kenji; Terada, Atsuhiko
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Fukushima, Hisashi*; Sato, Seichi*; Watanabe, Naoko*; Kozaki, Tamotsu*; Yamagishi, Isao; Nishihara, Kenji
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edges in BaTiOYoshii, Kenji; Yoneda, Yasuhiro; Jarrige, I.*; Suzuki, Chikashi; Ito, Yoshiaki*; Yoshikado, Shinzo*; Fukushima, Sei*
no journal, ,
We have observed the electronic structures of ferroelectric BaTiO by means of resonant X-ray emission spectroscopy (RXES) at Ba-L and Ti-K edges. High- resolution X-ray absorption spectra using RXES at Ba-L edge showed no temperature dependence below and above the Curie temperature. This result is different from the previous data, in which the change of spectral shape suggested the displasive mechanism. Thus, a careful reexamination is needed in future. The RXES measurements at Ti-K edge showed the presence of fluorescence peak only, indicating that the excited electron is raplidly delocalied. This suggests the strong covalency between Ti and O and is consistent with the previously proposed mechanism of the ferroelectricity.
using resonant X-ray emission at Ba L and Ti K edgesYoshii, Kenji; Yoneda, Yasuhiro; Jarrige, I.*; Fukuda, Tatsuo; Nishihata, Yasuo; Suzuki, Chikashi; Ito, Yoshiaki*; Yoshikado, Shinzo*; Fukushima, Sei*
no journal, ,
We have studied the electronic properties of the ferroelectric barium titanate BaTiO using resonant X-ray emission spectroscopy (RXES) and X-ray absorption spectroscopy in the partial fluorescence mode (PFY-XAS) at the Ba L and Ti K absorption edges. Contrary to a previous study, we found no fine structure in the pre-edge area of the PFY-XAS spectrum at the Ba L3 edge, and no temperature-induced spectral change was observed across the Curie temperature (130C). This result is not supportive of the possible presence of the displacement around Ba at the Curie temperature. RXES spectra were measured at the Ti K edge. The photon energy of the emission peak is found to be nearly constant throughout the absorption edge for all three compounds. We deduce the Ti 3d states to have a delocalized character, in contrast with the Ba 5d states, a property which is consistent with the proposed scenario of the formation of electric dipoles in BaTiO.
Hasegawa, Takayuki*; Uemura, Masaharu*; Takueuchi, Kazuki*; Kodaka, Takuya*; Fukada, Noboru*; Umesaki, Norimasa*; Fukushima, Sei*; Teraoka, Yuden; Haruyama, Yuichi*; Niibe, Masahito*; et al.
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