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Ito, Takashi; Higemoto, Wataru; Sakai, Akito*; Nakatsuji, Satoru*; Tsujimoto, Masaki*
Physical Review B, 92(12), p.125151_1 - 125151_5, 2015/09
Times Cited Count:5 Percentile:23.64(Materials Science, Multidisciplinary)Tsujimoto, Kazufumi; Sasa, Toshinobu; Maekawa, Fujio; Matsumura, Tatsuro; Hayashi, Hirokazu; Kurata, Masaki; Morita, Yasuji; Oigawa, Hiroyuki
Proceedings of 21st International Conference & Exhibition; Nuclear Fuel Cycle for a Low-Carbon Future (GLOBAL 2015) (USB Flash Drive), p.657 - 663, 2015/09
To continue the utilization of the nuclear fission energy, the management of the high-level radioactive waste is one of the most important issues to be solved. Partitioning and Transmutation technology of HLW is expected to be effective to mitigate the burden of the HLW disposal by reducing the radiological toxicity and heat generation. The Japan Atomic Energy Agency (JAEA) has been conducting the research and development on accelerator-driven subcritical system (ADS) as a dedicated system for the transmutation of long-lived radioactive nuclides. This paper overviews the recent progress and future R&D plan of the study on the ADS and related fuel cycle technology in JAEA.
Minato, Kazuo; Morita, Yasuji; Tsujimoto, Kazufumi; Koyama, Shinichi; Kurata, Masaki*; Inoue, Tadashi*; Ikeda, Kazumi*
Proceedings of 11th OECD/NEA Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation (Internet), p.341 - 349, 2012/00
In order to provide a quantitative assessment for the maturity of the partitioning and transmutation technology relative to its full-scale deployment, a technology readiness level (TRL) process was used. The definitions of TRL used in this study were based on those used in the Global Nuclear Energy Partnership (GNEP). The TRL was evaluated and the technology pathway was discussed for the systems of FBR and ADS for the minor actinides (MA) transmutation, MA partitioning processes, and MA-bearing fuels. Through the evaluation, it was recognized that hard requirements to be satisfied were present at TRL 5 for each technology development. The introduction of lab-scale tests with actual spent fuel for MA partitioning process and with actual separated materials for MA-bearing fuels fabrication and irradiation before the engineering scale tests may be effective and efficient solution.
Tsujimoto, Yoshihiro*; Yamaura, Kazunari*; Hayashi, Naoaki*; Kodama, Katsuaki; Igawa, Naoki; Matsushita, Yoshitaka*; Katsuya, Yoshio*; Shirako, Yuichi*; Akaogi, Masaki*; Muromachi, Eiji*
Chemistry of Materials, 23(16), p.3652 - 3658, 2011/08
Times Cited Count:27 Percentile:61(Chemistry, Physical)Topotactic reaction of the Ruddlesden-Popper phase SrFeO ( 0.18) with polytetrafluoroethylene yields a highly fluorinated phase SrFeOF (x 0.44), compared with SrFeOF prepared by the reaction of SrFeO and F gas. Structure analyses based on powder neutron diffraction, synchrotron powder diffraction, and Fe Mssbauer spectroscopy measurements demonstrate that the new oxyfluoride perovskite has no anion deficiencies and adopts the tetragonal structure (space group 4/) with lattice constants = 3.87264(6) and = 21.3465(6) at room temperature. The fluoride ions preferentially occupy the terminal apical anion sites with oxide ions in a disordered manner, which results in square pyramidal coordination around iron.
Takeyasu, Masanori; Iida, Takao*; Tsujimoto, Tadashi*; Yamasaki, Keizo*; Ogawa, Yoshihiro*
Journal of Environmental Radioactivity, 88(1), p.74 - 89, 2006/00
Times Cited Count:25 Percentile:49.03(Environmental Sciences)The concentrations of Pb and Bi in rainwater was measured by a low background Ge detector. The concentrations of Pb and Bi were inverse relations with rainfall rate in some rainfall events, and the concentration ratio of Bi to Pb would be a weak inverse relation with rainfall rate. The model was considered about the scavenging effects of rainfall to Radon decay products, and those results were discussed with the model.
Takeyasu, Masanori; Iida, Takao*; Tsujimoto, Tadashi*; Yamasaki, Keizo*
International Congress Series, 1276, p.289 - 290, 2004/00
The each concentration of Pb and Bi in rainwater was measured by a low background Ge detector. The concentration ofPb was a inverse relation with rainfall rate in some rainfall events, and the concentration ratio ofBi toPb was a weak inverse relation with rainfall rate in all rainfall events. These relations were the same as these obtained by the removal model of radon decay products from stratiform cloud.
Takeyasu, Masanori; Iida, Takao*; Tsujimoto, Tadashi*; Yamasaki, Keizo*
Proceedings of 6th International Conference on High Levels of Natural Radiation and Radon Areas, Program & Abstracts, (P-22), 85 Pages, 2004/00
The concentrations and its ratio of Pb-214 and Bi-214 in rainwater were measured by -ray spectrometry with a low background Ge detector, and the results were compared with the scavenging model of radon decay products from the atmosphere by precipitation. The each concentration of Pb-214 and Bi-214 in rainwater was constant and independent on precipitation rate for some precipitation events, and expressed with a power function of precipitation rate for the other events. The activity ratio of Bi-214 to Pb-214 was observed weak inverse correlated with precipitation rate. The measured ratio agreed fairly well with calculated one by the model.
Ando, Masaki; Osugi, Toshitaka; Tsujimoto, Kazufumi
JAERI-Data/Code 98-012, 35 Pages, 1998/03
no abstracts in English
Tsujimoto, Yoshihiro*; Yamaura, Kazunari*; Matsushita, Yoshitaka*; Muromachi, Eiji*; Hayashi, Naoaki*; Kodama, Katsuaki; Igawa, Naoki; Shirako, Yuichi*; Akaogi, Masaki*
no journal, ,
Topotactic reaction of the n = 2 Ruddlesden-Popper phase SrFeO with the Teflon polymer yields a highly fluorinated phase SrFeOO (x 0.44). The crystal/magnetic structures and anion composition are determined by a combination of neutron diffraction and Fe Mssbauer spectroscopy experiments. Fluoride anions selectively occupy the terminal apical anion sites, leading to the square pyramidal coordination around the Fe metal center. The oxyfluoride material adopts a simple antiferromagnetic ordered structure with k = (1/2 1/2 0) below 390 K.
Fukushima, Masahiro; Ando, Masaki; Nagaya, Yasunobu; Sakurai, Takeshi; Tsujimoto, Kazufumi
no journal, ,
We will report on our current activities and future plans for utilizing the integral experiment data accumulated in Fast Critical Assembly (FCA).