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Takato, Kiyoto; Murakami, Tatsutoshi; Suzuki, Kiichi; Shibanuma, Kimikazu; Hatanaka, Nobuhiro; Yamaguchi, Bungo; Tobita, Yoshimasa; Shinozaki, Masaru; Iimura, Naoto; Okita, Takatoshi; et al.
JAEA-Technology 2013-026, 42 Pages, 2013/10
JAEA-Technology-2013-026.pdf:3.17MB
In order to cope with making a commercial fast reactor fuel burn-up higher, oxygen-to-metal (O/M) ratio in the fuel specification is designed to 1.95. As the test for the fabrication of such low O/M ratio pellets, two kinds of O/M ratio preparation tests of different reduction mechanism were done. In the first test, we evaluated the technology to prepare the O/M ratio low by annealing the sintered pellets in production scale. In addition, we know from past experience that O/M ratio of the sintered pellets can be reduced by residual carbon when the de-waxed pellets with high carbon content are sintered. Thus, in another test, the green pellets containing a large amount of organic additives were sintered and we evaluated the technology to produce the low O/M ratio sintered pellets by the reduction due to residual carbon. From the first test results, we found a tendency that the higher annealing temperature or the longer annealing time resulted in the lower O/M ratio. However, the amount of O/M ratio reduction was small and it is estimated that a substantial annealing time is necessary to prepare the O/M ratio to 1.95. It is considered that reducing O/M ratio by annealing was difficult because atmosphere gas containing oxygen released from pellets remained and the O/M ratio was changed to the value equilibrated with the gas having high oxygen potential. From another test results, it was confirmed that O/M ratio was reduced by the reduction due to residual carbon. We found that it was important to manage an oxygen potential of atmosphere gas in a sintering furnace low to reduce the O/M ratio effectively.
Fujii, Hirofumi*; Hara, Kazuhiko*; Hashimoto, Shugo*; Ito, Fumiaki*; Kakuno, Hidekazu*; Kim, S.*; Kochiyama, Mami; Nagamine, Kanetada*; Suzuki, Atsuto*; Takada, Yoshihisa*; et al.
Progress of Theoretical and Experimental Physics (Internet), 2013(7), p.073C01_1 - 073C01_20, 2013/07
Times Cited Count：26 Percentile：76.73(Physics, Multidisciplinary)Murakami, Tatsutoshi; Kato, Masato; Suzuki, Kiichi; Uno, Hiroki*
Proceedings of 2010 International Congress on Advances in Nuclear Power Plants (ICAPP '10) (CD-ROM), p.1859 - 1865, 2010/06
The sintering behavior of the de-waxed pellets containing about 3000 ppm of carbon was analyzed during the sintering process using thermal gravimetry and dilatometer measurements as a parameter of the ratio of hydrogen partial pressure-to-moisture partial pressure (H
/HO) in the sintering atmosphere. The attained O/M ratio and the shrinkage rate increased with decreasing H/HO ratio in the sintering atmosphere. As a result, it is considered that a carbothermic reduction caused the significant decrease of the O/M ratio in the case of the sintering in the atmosphere of high H/HO ratio. In contrast, decrement of O/M ratio could be inhibited by keeping the oxygen potential of the atmosphere high in the case of the sintering in the atmosphere of lower H/HO ratio.
Yogo, Akifumi; Sato, Katsutoshi; Nishikino, Masaharu; Mori, Michiaki; Teshima, Teruki*; Numasaki, Hodaka*; Murakami, Masao*; Demizu, Yusuke*; Akagi, Takashi*; Nagayama, Shinichi*; et al.
Applied Physics Letters, 94(18), p.181502_1 - 181502_3, 2009/05
Times Cited Count：110 Percentile：94.75(Physics, Applied)Murakami, Tatsutoshi; Suzuki, Kiichi; Hatanaka, Nobuhiro; Hanawa, Yukio; Shinozaki, Masaru; Murakami, Shinichi; Tobita, Yoshimasa; Kawasaki, Takeshi; Kobayashi, Yoshihito; Iimura, Naoto; et al.
JAEA-Technology 2008-017, 97 Pages, 2008/03
JAEA-Technology-2008-017.pdf:2.76MB
Low density MOX pellets for FBR "MONJU" have not been fabricated in Plutonium Fuel Fabricating Facility (PFPF) for these 9 years since completion of the first reload fuel for "MONJU" in 1995. In this period, about 60 % of machines in the pellet fabrication process of PFPF have been replaced with new ones, and fabrication of MOX pellets for "JOYO" has been continued using these machines. Concerning the feed MOX powders for "MONJU", the amount of decay heat has been increased with increase of accumulated Am-241 in this period. In addition, powder characteristic of recycled MOX powder which is one of feed powders, MH-MOX powder, UO powder and recycled MOX powder, was significantly changed by replacing former processing machine used for scrap recycling with improved one. Using MOX powder with increased decay heat and recycled MOX powder processed by new machine, a series of low density MOX pellet fabrication tests were conducted to confirm pellet fabrication conditions for current pellet fabrication machines from October in 2004 to August in 2006. As a conclusion, it was confirmed that low density MOX pellets could be fabricated using these feed powders and replaced machines by adjusting pellet fabrication conditions adequately. This report summarizes the results of a series of low density MOX pellet fabrication tests.
Murakami, Tatsutoshi; Suzuki, Kiichi; Aono, Shigenori
Proceedings of International Conference on Advanced Nuclear Fuel Cycles and Systems (Global 2007) (CD-ROM), p.891 - 896, 2007/09
no abstracts in English
Hamada, Kazuya; Nakajima, Hideo; Kawano, Katsumi; Takano, Katsutoshi; Tsutsumi, Fumiaki; Okuno, Kiyoshi; Suzuki, Tomio; Fujitsuna, Nobuyuki*
Cryogenics, 47(3), p.174 - 182, 2007/03
Times Cited Count：30 Percentile：71.82(Thermodynamics)no abstracts in English
Hamada, Kazuya; Nakajima, Hideo; Kawano, Katsumi; Takano, Katsutoshi; Tsutsumi, Fumiaki; Okuno, Kiyoshi; Suzuki, Tomio; Fujitsuna, Nobuyuki*
Teion Kogaku, 41(3), p.131 - 138, 2006/03
no abstracts in English
Suzuki, Masatoshi; Hazawa, Tomoya; Ishizaki, Yoichi*; Obara, Michio*; Inada, Katsutoshi*; Yonekawa, Mitsunori*; Wakita, Hiroshi*
JAERI-Tech 2004-060, 153 Pages, 2004/09
JAERI-Tech-2004-060.pdf:9.78MB
The cold neutron source (CNS) at JRR-3 was constructed for the purpose of improving the utilization performance of the reactor along the lines of upgrade program. There are two methods for extracting cold neutrons from a reactor, one is to filter a small fraction of cold neutrons in the Maxwellian spectrum of reactor neutrons while the other is to increase the fraction of cold neutron by inserting a cryogenic moderator. The latter is adopted as CNS facilities at almost all cases, and liquid hydrogen and its cooling system are equipped with a cold neutron source at many neutron facilities just like JRR-3. Cold neutrons generated in a cold source are extracted through a neutron guide tube, and are utilized for the purpose of neutron beam experiments such as neutron scattering which study the structures of atoms and molecules in the materials and life science fields. This report summarizes the operation data and the main technical issues which were recorded in the whole operation period from commencement date in 1989 to March 2004.
Suzuki, Ryosuke*; Tanabe, Kentaro*; kondo, koki*; Ono, Katsutoshi*; Toda, Shinichi; Kasagawa, Yusuke; Tamayama, Kiyoshi; Oketani, Kazuhiro*
JNC TY4400 2003-004, 214 Pages, 2003/08
JNC-TY4400-2003-004.pdf:19.93MB
Recently, it has been important to reuse discharged heat energy from present nuclear plants in the view of reduction of environmental burden and improvement of heat efficiency for plant. For practical use in future of sodium cooled FBRs, which are typical high temperature system, this issue must be given priority. The thermal electric conversion system has been applied to the limited uses such as space or military, however, that results show good merits for reliability, maintenance free, and so on. Recently, this technology has been reconsidered in the view of saving energy in general industry. In this study, we made an investigation for applicability of the thermal electric conversion system to sodium cooled FBR as a heat recovery techbnology. Exactly, We have carried out the fundamental research and development for thermoelectric materials and elements, development of modules, and sodium tests with those modules, and then, we acquired the fundamental knowledge to estimate the efficiencies of thermal electric conversion system or modules for a sodium cooled FBR.
Aoyama, Takafumi; Suzuki, Toshiaki; Takatsuto, Hiroshi; Oowada, Toshio; Oyama, Nobumi; Emori, Shuichi
PNC TN9418 97-006, 93 Pages, 1997/12
non
Uehara, Kazuya; Ikeda, Yoshitaka; Saigusa, Mikio; Sakamoto, Keishi; Fujii, Tsuneyuki; Maebara, Sunao; Tsuneoka, Masaki; Seki, Masami; Moriyama, Shinichi; Kobayashi, Noriyuki*; et al.
Fusion Engineering and Design, 19(1), p.29 - 40, 1992/07
Times Cited Count：1 Percentile：17.26(Nuclear Science & Technology)no abstracts in English
Murakami, Tatsutoshi; Suzuki, Kiichi; Aono, Shigenori
no journal, ,
no abstracts in English
Suzuki, Kiichi; Murakami, Tatsutoshi; Aono, Shigenori
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no abstracts in English
Murakami, Tatsutoshi; Kato, Masato; Suzuki, Kiichi; Uno, Hiroki*
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no abstracts in English
Murakami, Tatsutoshi; Shibanuma, Kimikazu; Hanawa, Yukio; Yamaki, Takao; Suzuki, Mitsuru; Aono, Shigenori
no journal, ,
MOX powder containing organic additives is loaded in a hopper. The hopper has a cooling function to mitigate heat deterioration of organic additives, but its cooling may not be enough for higher order plutonium in the future. So temperature measurement of MOX powder in the hopper was carried out as a preliminarily test for development of cooling hopper.
Suzuki, Kiichi; Takeuchi, Kentaro; Murakami, Tatsutoshi; Kato, Masato; Uno, Hiroki*; Sunaoshi, Takeo*
no journal, ,
no abstracts in English
Murakami, Tatsutoshi; Suzuki, Kiichi; Shibanuma, Kimikazu; Aono, Shigenori
no journal, ,
no abstracts in English
Suzuki, Kiichi; Murakami, Tatsutoshi; Aono, Shigenori; Hatanaka, Nobuhiro; Takano, Tatsuo
no journal, ,
no abstracts in English
Murakami, Tatsutoshi; Shibanuma, Kimikazu; Yamaguchi, Bungo; Takato, Kiyoto; Suzuki, Kiichi; Aono, Shigenori
no journal, ,
no abstracts in English
