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Nagai, Takayuki; Okamoto, Yoshihiro; Yamagishi, Hirona*; Shibata, Daisuke*; Kojima, Kazuo*; Hasegawa, Takehiko*; Sato, Seiichi*; Fukaya, Akane*; Hatakeyama, Kiyoshi*
JAEA-Research 2023-004, 45 Pages, 2023/09
The local structure of glass-forming elements and waste elements in borosilicate glasses varies with its chemical composition. In this study, simulated waste glass samples were prepared and the chemical state regarding boron (B), silicon (Si) and waste elements of iron (Fe), cesium (Cs) were estimated by using XAFS measurement in soft X-ray region. To understand the chemical stability of simulated waste glasses, XANES spectra of B K-edge, Fe L, L-edge, and Cs M, M-edge were measured on the glass surface exposed to the leachate. As a result, it was found that the glass surface exposed to the leachate was changed and it was difficult to obtain a clear XANES spectrum. From the B K-edge XANES spectra on glass surfaces exposed to the leachate, an increase in three-coordination of B-O (BO) and a decrease in four-coordination of B-O (BO) were observed compared to the glass surfaces before immersion. The XANES spectra of Fe L, L-edge, and Cs M, M-edge show that as the exposure time in the leachate increases, the Cs present on the glass surface dissolves into the leachate. The XANES spectra of Si K-edge were measured on simulated waste glass surfaces before immersion, and it was confirmed that the change in XANES spectra given by NaO concentration had a larger effect than the waste component concentration.
Takeda, Tetsuaki*; Inagaki, Yoshiyuki; Aihara, Jun; Aoki, Takeshi; Fujiwara, Yusuke; Fukaya, Yuji; Goto, Minoru; Ho, H. Q.; Iigaki, Kazuhiko; Imai, Yoshiyuki; et al.
High Temperature Gas-Cooled Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.5, 464 Pages, 2021/02
As a general overview of the research and development of a High Temperature Gas-cooled Reactor (HTGR) in JAEA, this book describes the achievements by the High Temperature Engineering Test Reactor (HTTR) on the designs, key component technologies such as fuel, reactor internals, high temperature components, etc., and operational experience such as rise-to-power tests, high temperature operation at 950C, safety demonstration tests, etc. In addition, based on the knowledge of the HTTR, the development of designs and component technologies such as high performance fuel, helium gas turbine and hydrogen production by IS process for commercial HTGRs are described. These results are very useful for the future development of HTGRs. This book is published as one of a series of technical books on fossil fuel and nuclear energy systems by the Power Energy Systems Division of the Japan Society of Mechanical Engineers.
Ohashi, Hirofumi; Goto, Minoru; Ueta, Shohei; Sato, Hiroyuki; Fukaya, Yuji; Kasahara, Seiji; Sasaki, Koei; Mizuta, Naoki; Yan, X.; Aoki, Takeshi*
Proceedings of 9th International Topical Meeting on High Temperature Reactor Technology (HTR 2018) (USB Flash Drive), 6 Pages, 2018/10
Conceptual design study of an experimental HTGR is performed to upgrade the plant system from Japanese High Temperature engineering Test Reactor (HTTR) to a commercial HTGR. Safety systems of HTTR are upgraded to demonstrate the commercial HTGR concept, such as a passive reactor cavity cooling system, a confinement, etc. An intermediate heat exchanger (IHX) is replaced by a steam generator (SG) for a process heat supply to demonstrate the technology for a commercial use. This paper describes the conceptual design study results of the plant system of the experimental HTGR.
Fukaya, Yuji; Kasahara, Seiji; Mizuta, Naoki; Inaba, Yoshitomo; Shibata, Taiju; Nishihara, Tetsuo
JAEA-Research 2018-004, 38 Pages, 2018/06
The demand of HTGR to investigate its introduction scenario and heat balance of HTGR have been researched. First, previous studies of HTGR demand were researched. Next, heat balance of GTHTR300, a commercial scale HTGR design, and its characteristics were researched. By using this information, installation number of HTGR to suit for demand in Japan are evaluated. In addition, heat balance evaluation code was developed in this study.
Teshigawara, Makoto; Ikeda, Yujiro; Oi, Motoki; Harada, Masahide; Takada, Hiroshi; Kakishiro, Masanori*; Noguchi, Gaku*; Shimada, Tsubasa*; Seita, Kyoichi*; Murashima, Daisuke*; et al.
Nuclear Materials and Energy (Internet), 14, p.14 - 21, 2018/01
Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)We developed an Au-In-Cd (AuIC) decoupler material to reduce induced radioactivity instead of Ag-In-Cd one, which has a cut off energy of 1eV. In order to implement it into an actual moderator-reflector assembly, a number of critical engineering issues need to be resolved with regard to large-sized bonding between AuIC and A5083 alloys by the hot isostatic pressing process. We investigated this process in terms of the surface conditions, sizes, and heat capacities of large AuIC alloys. We also show a successful implementation of an AuIC decoupler into a reflector assembly, resulting in a remarkable reduction of radioactivity by AuIC compared to AIC without sacrificing neutronic performance.
Mochizuki, Izumi*; Ariga, Hiroko*; Fukaya, Yuki; Wada, Ken*; Maekawa, Masaki*; Kawasuso, Atsuo*; Shidara, Tetsuo*; Asakura, Kiyotaka*; Hyodo, Toshio*
Hyomen Kagaku, 37(9), p.451 - 456, 2016/09
no abstracts in English
Mochizuki, Izumi*; Ariga, Hiroko*; Fukaya, Yuki; Wada, Ken*; Maekawa, Masaki; Kawasuso, Atsuo; Shidara, Tetsuo*; Asakura, Kiyotaka*; Hyodo, Toshio*
Physical Chemistry Chemical Physics, 18(10), p.7085 - 7092, 2016/03
Times Cited Count:18 Percentile:62.79(Chemistry, Physical)no abstracts in English
Fukaya, Hiroyuki; Suyama, Kenya; Sonoda, Takashi; Okubo, Kiyoshi; Umeda, Miki; Uchiyama, Gunzo
JAEA-Research 2013-020, 81 Pages, 2013/10
Japan Atomic Energy Agency conducted a project "Isotopic Composition measurement of Fission Products in Spent Fuel from FY2008 to FY2011" by the entrustment of Japan Nuclear Energy Safety Organization. In that project, we measured the isotopic composition of neodymium isotopes which are important to evaluate the burnup value of spent nuclear fuel by using two different methods and obtained different results. So that we carried out the follow-up measurement in order to investigate the reason of the difference between two neodymium measurements. It was found that we needed correction to the measurement results of neodymium for two samples and a part of other fission products for all samples in total five samples. This report summarizes the all works carried out in this follow-up measurement and obtained results.
Sakazume, Yoshinori; Aoki, Hiromichi; Haga, Takahisa; Fukaya, Hiroyuki; Sonoda, Takashi; Shimizu, Kaori; Niitsuma, Yasushi*; Ito, Mitsuo; Inoue, Takeshi
JAEA-Technology 2007-069, 44 Pages, 2008/02
Analysis of the uranyl nitrate solution fuel is carried out at the analytical laboratory of NUCEF (Nuclear Fuel Cycle Engineering Research Facility), which provides essential data for operation of STACY (Static Experiment Critical Facility), TRACY (Transient Experiment Critical Facility) and the fuel treatment system. Analyzed in FY 2006 were uranyl nitrate solution fuel samples taken before and after experiments of STACY and TRACY, samples for the preparation of uranyl nitrate solution fuel, and samples for nuclear material accountancy purpose. The total number of the samples analyzed in FY 2006 was 254. This report summarizes work related to the analysis and management of the analytical laboratory in the FY 2006.
Fukaya, Hiroyuki; Aoki, Hiromichi; Haga, Takahisa; Nishizawa, Hidetoshi; Sonoda, Takashi; Sakazume, Yoshinori; Shimizu, Kaori; Niitsuma, Yasushi*; Shirahashi, Koichi; Inoue, Takeshi
JAEA-Technology 2007-005, 27 Pages, 2007/03
Analysis of the uranyl nitrate solution fuel is carried out at the analytical laboratory of NUCEF (Nuclear Fuel Cycle Engineering Research Facility), which provides essential data for operation of STACY (Static Experiment Critical Facility), TRACY (Transient Experiment Critical Facility) and the fuel treatment system. Analyzed in FY 2005 were uranyl nitrate solution fuel samples taken before and after experiments of STACY and TRACY, samples for the preparation of uranyl nitrate solution fuel, and samples for nuclear material accountancy purpose. Also analyzed were the samples from raffinate treatment and its preliminary tests. The raffinate was generated, since FY 2000, during preliminary experiments on U/Pu extraction-pulification to fix the operation condition to prepare plutonium solution fuel to be used for criticality experiments at STACY. This report summarizes work related to the analysis and management of the analytical laboratory in the FY 2005.
Nishizawa, Hidetoshi; Fukaya, Hiroyuki; Sonoda, Takashi; Sakazume, Yoshinori; Shimizu, Kaori; Haga, Takahisa; Sakai, Yutaka*; Akutsu, Hideyuki*; Niitsuma, Yasushi; Inoue, Takeshi; et al.
JAEA-Technology 2006-007, 24 Pages, 2006/03
Analysis of the uranyl nitrate solution fuel is carried out at the analytical laboratory of NUCEF(Nuclear Fuel Cycle Engineering Research Facility), which provides essential data for operation of STACY(Static Experiment Critical Facility), TRACY(Transient Experiment Critical Facility)and the fuel treatment system. Analyzed in FY 2004 were uranyl nitrate solution fuel samples taker before and after experiments of STACY and TRACY, samples for the preparation of uranyl nitrate solution fuel, and samples for nuclear material accountancy purpose. Also analyzed were the samples from raffinate treatment and its preliminary tests. The raffinate was generated, since FY 2000, during preliminary experiments on U/Pu extraction-pulification to fix the operation condition to prepare plutonium solution fuel to be used for criticality experiments at STACY. The total number of the samples analyzed in FY 2004 was 160. This report summarizes works related to the analysis and management of the analytical laboratory in the FY 2004.
Shimizu, Kaori; Gunji, Kazuhiko*; Haga, Takahisa*; Fukaya, Hiroyuki; Sonoda, Takashi; Sakazume, Yoshinori; Sakai, Yutaka*; Akutsu, Hideyuki; Niitsuma, Yasushi*; Inoue, Takeshi; et al.
JAERI-Tech 2004-078, 27 Pages, 2005/02
Analysis of the uranyl nitrate solution fuel are carried out at the analytical laboratory, NUCEF (the Nuclear Fuel Cycle Engineering Research Facility), which provide essential data for the operations of STACY (the Static Experiment Critical Facility), TRACY (the Transient Experiment Critical Facility) and the fuel treatment system.In the FY 2003, analysis of the uranyl nitrate solution fuel from STACY/TRACY on its pre- and post-operations, analysis of the uranyl nitrate solution under preparation stage for the fuel and analysis for nuclear material accountancy purpose, have been conducted. In addition, analysis on the third U/Pu extraction/separation tests among the preliminary tests to confirm adjustment condition of plutonium solution fuel for its further use at STACY from 2000, and analysis on the experiments to treat extraction waste, were conducted. A total number of analytical samples in the FY 2003 were 156.This report summarizes works related to the analysis and management of the analytical laboratory in the FY 2003.
Saito, Shigeru; Ouchi, Nobuo; Fukaya, Kiyoshi*; Ishiyama, Shintaro; Tsuchiya, Yoshinori; Nakajima, Hideo
JAERI-Tech 2003-027, 63 Pages, 2003/03
Around the super conducting (SC) coils of SC linear accelerator or fusion reactor, several kind of dissimilar materials bond will be needed. In recent years, pure titanium has been proposed as jacket material for SC coil of fusion reactor. Cu-alloys will be used for connection of SC coils. Cryogenic stainless steels have been development for structural material. Therefore, it is necessary to develop new bonding techniques and we started the bonding technology development by hot isostatic press (HIP) method to bond Cu-alloys with titanium and cryogenic stainless steels. In this experiments, optimization of HIP bonding condition and evaluation of bonding strength by metallurgical observation, tensile and bending tests were performed.
Saito, Shigeru; Fukaya, Kiyoshi*; Ishiyama, Shintaro; Sato, Kazuyoshi
Journal of Nuclear Materials, 307-311(2), p.1542 - 1546, 2002/12
Times Cited Count:37 Percentile:89.18(Materials Science, Multidisciplinary)no abstracts in English
Saito, Shigeru; Fukaya, Kiyoshi*; Ishiyama, Shintaro; Amezawa, Hiroo; Yonekawa, Minoru; Takada, Fumiki; Kato, Yoshiaki; Takeda, Takashi; Takahashi, Hiroyuki*; Nakahira, Masataka
Journal of Nuclear Materials, 307-311(Part2), p.1573 - 1577, 2002/12
Times Cited Count:2 Percentile:17.03(Materials Science, Multidisciplinary)no abstracts in English
Saito, Shigeru; Fukaya, Kiyoshi*; Ishiyama, Shintaro
JAERI-Tech 2002-058, 30 Pages, 2002/07
no abstracts in English
Saito, Shigeru; Ouchi, Nobuo; Ishiyama, Shintaro; Tsuchiya, Yoshinori*; Nakajima, Hideo; Fukaya, Kiyoshi*
JAERI-Tech 2002-048, 68 Pages, 2002/05
no abstracts in English
Saito, Shigeru; Fukaya, Kiyoshi*; Ishiyama, Shintaro; Sato, Ikuo*; Kusuhashi, Mikio*; Hatakeyama, Tsuyoshi*; Takahashi, Heishichiro*; Kikuchi, Mitsuru
JAERI-Tech 2002-047, 51 Pages, 2002/05
no abstracts in English
Kiuchi, Kiyoshi; Ioka, Ikuo; Tachibana, Katsumi; Suzuki, Tomio; Fukaya, Kiyoshi*; Inohara, Yasuto*; Kambara, Shozo; Kuroda, Yuji*; Miyamoto, Satoshi*; Ogura, Kazutomo*
JAERI-Research 2002-008, 63 Pages, 2002/03
no abstracts in English
Hamada, Shozo; Fukaya, Kiyoshi*; Kato, Chiaki; Yanagihara, Takao; Doi, Masamitsu*; Kiuchi, Kiyoshi
JAERI-Tech 2001-063, 49 Pages, 2001/10
The demonstration test for the acid recovery evaporator and the dissolver used in the major equipment of Rokkasho Reprocessing Plant (RRP), has been carried out. The mock-up miniature equipment has been employed to it. This test had been performed from April in 1998. The total time of demonstration test using the mock-up equipment is about two and half years, which corresponds to about 20,000 hours. After that, four of the seven heat transfer tubes used in the evaporator were drawn out and the corrosion level and the mechanical properties were evaluated for one of them. As a result, intergranular corrosion was recognized in the inner surface of the heat transfer tube and the corrosion depth at the grain boundary was statistically shown to be about one grain from the inner surface. Further, no change in mechanical properties was observed and growth of intergranular cracks in the inner surface of the specimen was found after flattering test.