Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Takada, Hiroshi; Naoe, Takashi; Kai, Tetsuya; Kogawa, Hiroyuki; Haga, Katsuhiro
Proceedings of 12th International Topical Meeting on Nuclear Applications of Accelerators (AccApp '15), p.297 - 304, 2016/00
In J-PARC, we have continuously been making efforts to operate a mercury target of a pulsed spallation neutron source with rated power of 1-MW. One of technical progresses is to mitigate cavitation damages at the target vessel front induced by the 3-GeV proton beam injection at 25 Hz. We have improved the performance of a gas micro-bubbles injection into the mercury target, resulting that no significant cavitation damages was observed on the inner surface of target vessel after operation for 2050 MWh with the 300-kW proton beam. Another progress is to suppress the release of gaseous radioactive isotopes, especially tritium, during the target vessel replacement. We have introduced a procedure to evacuate the target system by an off-gas processing apparatus when it is opened during the replacement operation, achieving to suppress the tritium release through the stack. For example, the amount of released tritium was 12.5 GBq, only 5.4% of the estimated amount, after the 2050 MWh operation. After these progresses, the operating beam power for the pulsed spallation neutron source was ramped up to 500-kW in April, 2015.
Oigawa, Hiroyuki; Minato, Kazuo; Kimura, Takaumi; Morita, Yasuji; Arai, Yasuo; Nakayama, Shinichi; Nishihara, Kenji
Proceedings of International Conference on Nuclear Energy System for Future Generation and Global Sustainability (GLOBAL 2005) (CD-ROM), 6 Pages, 2005/10
JAERI is engaging in the R&D on the Double-strata Fuel Cycle concept in accordance with the results of the check and review on the Partitioning and Transmutation (PT) technology made by the Atomic Energy Commission of Japan in 2000. As for the partitioning process, after the establishment of the "4-group Partitioning Process Concept", an innovative concept called ARTIST is also being studied. As for the fuel technology, minor actinide nitrides such as NpN and AmN were synthesized and their material properties have been measured. To reprocess the irradiated fuel, the pyrochemical process has been studied. The R&D of the accelerator-driven transmutation system are in progress for an accelerator, lead-bismuth, and a subcritical reactor. In addition, JAERI has started the high-intensity proton accelerator project (J-PARC), which includes the Transmutation Experimental Facility (TEF) as the Phase-II. The impact of PT technology on the backend of the nuclear energy utilization is also being discussed.
Asakura, Toshihide; Hotoku, Shinobu; Ban, Yasutoshi; Matsumura, Masakazu*; Kim, S.-Y.; Mineo, Hideaki; Morita, Yasuji
Proceedings of International Conference ATALANTE 2004 Advances for Future Nuclear Fuel Cycles, 5 Pages, 2004/06
In JAERI, PARC process based on PUREX technique has been studied to as the basis of future reprocessing. The key of concept is to obtain the products, U and Pu, within only a single extraction cycle by separating Np and Tc from U and Pu before U/Pu partition. Two flow-sheet tests on the process were performed with 44 GWd/t PWR spent-fuel solutions. It was demonstrated that remaining Np in raffinate from co-extraction could be decreased to 13 % compared to the dissolver solution with increased solvent flow rate and with increased nitric acid concentration of FP scrubbing solution. It was demonstrated that Np separation (selective reduction by n-butyraldehyde) efficiency could be improved from 36 % to 78 % by flow-sheet modification; increasing reductant concentration and scrubbing solution flow rate. The feasibility of the Tc separation technique by high acid scrubbing was demonstrated.
Meigo, Shinichiro; Harada, Masahide; Takada, Hiroshi
Proceedings of ICANS-XVI, Volume 3, p.1059 - 1067, 2003/07
In the neutronics design for the J-PARC facilities, transport codes of NMTC/JAM, MCNPX and MARS are used. In order to confirm the predict ability for these codes, it is important to compare with the experiment result. For the validation of the source term of neutron, the calculations are compared with the experimental spectrum of neutrons produced from thick target. Although slightly disagreement exists, NMTC/JAM, MCNPX and MARS are in good agreement with the experiment within by a factor of 2.
Uchiyama, Gunzo; Mineo, Hideaki; Asakura, Toshihide; Hotoku, Shinobu; Iizuka, Masaru*; Fujisaki, Susumu; Isogai, Hikaru; Ito, Yoshinori*; Sato, Makoto; Hosoya, Noriaki
Journal of Nuclear Science and Technology, 39(Suppl.3), p.925 - 928, 2002/11
no abstracts in English
Uchiyama, Gunzo; Mineo, Hideaki; Asakura, Toshihide; Hotoku, Shinobu
Proceedings of International Conference on Back-End of the Fuel Cycle: From Research to Solutions (GLOBAL 2001) (CD-ROM), 8 Pages, 2001/09
no abstracts in English
Uchiyama, Gunzo; Mineo, Hideaki; Hotoku, Shinobu; Asakura, Toshihide; Kamei, Kazushige; Watanabe, Makio; Nakano, Yuji*; Kimura, Shigeru; Fujine, Sachio
Progress in Nuclear Energy, 37(1-4), p.151 - 156, 2000/12
Times Cited Count:9 Percentile:54.43(Nuclear Science & Technology)no abstracts in English
Uchiyama, Gunzo; Mineo, Hideaki; Asakura, Toshihide; Hotoku, Shinobu; Kamei, Kazushige; Watanabe, Makio; Fujine, Sachio
Proceedings of 12th Pacific Basin Nuclear Conference (PBNC 2000), Vol.1, p.531 - 538, 2000/00
no abstracts in English
Uchiyama, Gunzo; Mineo, Hideaki; Asakura, Toshihide; Hotoku, Shinobu; Kamei, Kazushige; Watanabe, Makio; Fujine, Sachio
Proceedings of 2nd International Conference on Safewaste 2000, Vol.2, p.689 - 700, 2000/00
no abstracts in English
Mineo, Hideaki; ; *; Uchiyama, Gunzo; Fujine, Sachio
Proc. of 7th Int. Conf. on Radioactive Waste Mamagement and Environmental Remediation (ICEM '99)(CD-ROM), 3 Pages, 1999/00
no abstracts in English
Mineo, Hideaki; Uchiyama, Gunzo; Hotoku, Shinobu; Asakura, Toshihide; Kihara, Takehiro; *; ; Kimura, Shigeru; *; ; et al.
Proc. of Int. Conf. on Future Nuclear Systems (GLOBAL'99)(CD-ROM), 7 Pages, 1999/00
no abstracts in English
Uchiyama, Gunzo; Hotoku, Shinobu; Watanabe, Makio; Kamei, Kazushige; Mineo, Hideaki; Nakano, Yuji*; Kimura, Shigeru; Asakura, Toshihide; Fujine, Sachio
Proceedings of 7th International Conference on Radioactive Waste Management and Environmental Remediation (ICEM '99) (CD-ROM), p.5 - 0, 1999/00
no abstracts in English
Uchiyama, Gunzo; Asakura, Toshihide; Hotoku, Shinobu; Fujine, Sachio
Solvent Extr. Ion Exch., 16(5), p.1191 - 1213, 1998/00
Times Cited Count:13 Percentile:56.2(Chemistry, Multidisciplinary)no abstracts in English