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Myagmarjav, O.; Tanaka, Nobuyuki; Nomura, Mikihiro*; Noguchi, Hiroki; Imai, Yoshiyuki; Kamiji, Yu; Kubo, Shinji; Takegami, Hiroaki
Progress in Nuclear Energy, 137, p.103772_1 - 103772_7, 2021/07
Times Cited Count：6 Percentile：70.8(Nuclear Science & Technology)Kai, Tetsuya; Kamiyama, Takashi*; Hiraga, Fujio*; Oi, Motoki; Hirota, Katsuya*; Kiyanagi, Yoshiaki*
Journal of Nuclear Science and Technology, 55(3), p.283 - 289, 2018/03
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Tsujimoto, Kazufumi; Nagai, Yasuki
JAERI-Review 2005-004, 208 Pages, 2005/03
JAERI-Review-2005-004.pdf:82.79MB
The Working Group on Energy (WG) was organized under International Union of Pure and Applied Physics (IUPAP). The WG has been considering problems on future energy supply and role of physics to solve the subjects. As one of activities of the WG, a Workshop on Energy was held on May 13, 2004 at Center for Promotion of Computational Science and Engineering, Japan Atomic Energy Research Institute (JAERI) in Tokyo hosted by IUPAP and co-hosted by JAERI and High Energy Accelerator Research Organization. The objectives of this workshop are to suggest active contributions of pure and applied physics field to the solution of the energy problem and to advance research and development (R&D) of future energy through the discussions about present status, problem and prospect of different energy development in the world and in Japan. This report records the summary of the Workshop and, abstracts and materials of 12 presentations. After the invited presentations about overview of energy problems in the world, in China and in Japan, R&D activities on the following four fields were presented; "Research and Development of New Energy", "Research and Development of Fusion Energy", "Prospect of Accelerator Driven System (ADS)", and "Hydrogen Production, Storage and Transportation".
Harada, Masahide; Watanabe, Noboru; Teshigawara, Makoto; Kai, Tetsuya; Ikeda, Yujiro
Nuclear Instruments and Methods in Physics Research A, 539(1-2), p.345 - 362, 2005/02
Times Cited Count：21 Percentile：78.97(Instruments & Instrumentation)Neutronic studies of decoupled hydrogen moderators were performed by calculations taking into account para hydrogen content, decoupling energy, moderator dimensions/shapes and reflector material. Low-energy parts of calculated spectral intensities with different para hydrogen contents were analyzed by a modified Maxwell function to characterize neutron spectra. The result shows that a 100% para hydrogen moderator gives the highest pulse peak intensity together with the narrowest pulse width and the shortest decay times. Pulse broadening with a reflector was explained by time distributions of source neutrons entering into the moderator through a decoupler. Material dependence of time distribution was studied. A decoupling energy higher than 1 eV does not bring about a large improvement in pulse widths and decay times, even at a large penalty in the peak intensity. The optimal moderator thickness was also discussed for a rectangular parallelepiped shape and a canteen shape moderators.
Ogawa, Masuro; Nishihara, Tetsuo
Nuclear Engineering and Design, 233(1-3), p.5 - 10, 2004/10
Times Cited Count：27 Percentile：83.6(Nuclear Science & Technology)An amount of primary energy supply in Japan is increasing year by year. Much energy such as oil, coal and natural gas is imported so that the self-sufficiency ratio in Japan is only 20 % even if including nuclear energy. An amount of energy consumption is also increasing especially in commercial and resident sector and transport sector. As a result, a large amount of greenhouse gas was emitted into the environment. Nuclear energy plays the important role in energy supply in Japan. Japan Atomic Energy Research Institute (JAERI) has been carried out research and development of a hydrogen production system using a high temperature gas cooled reactor (HTGR). The HTTR project aims at the establishment of the HTGR hydrogen production system. Reactor technology of the HTGR, hydrogen production technology with thermochemical water splitting process and system integration technology between the HTGR and a hydrogen production plant are developed in the HTTR project.
5(012) tilt grain boundaryYamaguchi, Masatake; Shiga, Motoyuki; Kaburaki, Hideo
Journal of the Physical Society of Japan, 73(2), p.441 - 449, 2004/02
Times Cited Count：23 Percentile：71.32(Physics, Multidisciplinary)The electronic structures of 5(012) symmetrical tilt grain boundary (GB) and (012) free surface (FS) systems for nickel including hydrogen are calculated by the full-potential linearized augmented plane wave method with the generalized gradient approximation. The difference of the binding energies between the 5(012)GB/FS site and the inner bulk site is obtained as the GB/FS segregation energy, and the difference between GB and FS segregation energies as the embrittling potency energy. The segregation position of hydrogen atom is determined by the force minimization. We find that hydrogen atom prefers 5(012)GB to inner bulk energetically by about 0.3 eV/H, while it prefers (012)FS to the GB by about 0.3-0.4 eV/H. The open space at GB may be occupied by an additional interstitial Ni atom since it increases the GB energy by only about 10%. In this case, the GB segregation energy of hydrogen reduces, which makes the segregation difficult. The calculated zero-point energies of hydrogen at inner bulk, GB, and FS sites are within 0.12-0.16eV/H.
Ohashi, Hirofumi; Inagaki, Yoshiyuki
JAERI-Tech 2003-046, 47 Pages, 2003/05
JAERI-Tech-2003-046.pdf:3.15MB
no abstracts in English
Nomura, Mikihiro; Kasahara, Seiji; Onuki, Kaoru
JAERI-Research 2002-039, 24 Pages, 2003/01
JAERI-Research-2002-039.pdf:1.01MB
Thermal efficiency to produce hydrogen from water through the IS process was evaluated by a viewpoint of thermodynamics. Thermal efficiency is decided by a temperature from a heat source and limited by the works calculated by the Carnot efficiency for any hydrogen production methods. The maximum thermal efficiency is 81.3% for a thermal cycle between 1123K and 733K. The thermal efficiency of the IS process was evaluated by G-T diagrams of each reactions and separation processes. The maximum value is 78.2% without considering the works for separations of acids from water. However, the effects of the works for separations on thermal efficiency are essential for the IS process, because Gibbs energies of separations of acids from water are always positive. The thermal efficiency could be changed from 53.5% to 76.6% by the calculation with or without the separation processes.
Harada, Masahide; Teshigawara, Makoto; Kai, Tetsuya; Sakata, Hideaki*; Watanabe, Noboru; Ikeda, Yujiro
Journal of Nuclear Science and Technology, 39(8), p.827 - 837, 2002/08
Times Cited Count：18 Percentile：73.17(Nuclear Science & Technology)For a decoupled hydrogen (super critical) moderator, optimization studies have been performed on a premoderator and reflector material (Pb, Be, Fe and Hg) together with the decoupling energy to realize a higher neutronic performance. The result indicated that the best neutronic performance could be obtained for a decoupled H
moderator in a Pb reflector by optimizing the premoderator and adopting an appropriate decoupling energy, even compared with optimized one in a Be reflector.
Shiozawa, Shusaku
Nihon Kikai Gakkai Doryoku Enerugi Shisutemu Bumon Nyusu Reta, (24), p.2 - 3, 2002/05
no abstracts in English
Ohashi, Hirofumi; Inagaki, Yoshiyuki; Ogawa, Masuro; Onuki, Kaoru; Takeda, Tetsuaki; Nishihara, Tetsuo; Hayashi, Koji; Inaba, Yoshitomo; Shiozawa, Shusaku
Suiso Enerugi Shisutemu, 26(2), p.23 - 28, 2001/12
no abstracts in English
Harada, Masahide; Teshigawara, Makoto; Kai, Tetsuya; Sakata, Hideaki*; Watanabe, Noboru; Ikeda, Yujiro
JAERI-Research 2001-016, 32 Pages, 2001/03
JAERI-Research-2001-016.pdf:1.74MB
An optimization study on the premoderator, the reflector material choice and a length of the liner is carried out for the design of high performance decoupled hydrogen moderator. NMTC/JAM and MCNP-4C are used for the neutronics calculation. The result indicates that, assuming premoderator dimensions and decoupling energy is controlled, the decoupled hydrogen moderator with a premoderator can provide better pulse characteristics than that without the premoderator for a Be reflector. On the selection of the reflector material, it is clearly shown that Pb and Hg reflectors give merits in using the premoderator for higher intensity and reduction of energy deposition in moderator. It is also shown that a H2O premoderator provides a short tail while a D2O premoderator provides the high peak intensity. Minimum liner length is evaluated to be 20 cm from the viewpoint of neutronics.
Sagisaka, Akito*; Nagashima, Keisuke; Yamagiwa, Mitsuru; Matoba, Toru; *
Journal of the Physical Society of Japan, 68(4), p.1221 - 1227, 1999/04
Times Cited Count：2 Percentile：26.13(Physics, Multidisciplinary)no abstracts in English
*
Suiso Enerugi Shisutemu, 22(2), p.74 - 75, 1997/00
no abstracts in English
Yamakawa, Koiji*; Maeta, Hiroshi
Scr. Metall. Mater., 32(7), p.967 - 970, 1995/00
no abstracts in English
Yamakawa, Koiji*; Maeta, Hiroshi
Scr. Metall. Mater., 31(7), p.803 - 808, 1994/00
no abstracts in English
*; Nakamura, Kazuyuki; Okumura, Yoshikazu; Shinto, Katsuhiro*
Dai-4-Kai Ryushisen No Sentanteki Oyo Gijutsu Ni Kansuru Shimpojiumu, p.19 - 22, 1993/00
no abstracts in English
Maeta, Hiroshi; Yamakawa, Koiji*
Defect Diffus. Forum, 95-98, p.305 - 310, 1993/00
no abstracts in English
Nakashima, Mikio; Aratono, Yasuyuki
Radiation Physics and Chemistry, 41(3), p.461 - 465, 1993/00
Times Cited Count：20 Percentile：85.05(Chemistry, Physical)no abstracts in English
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JAERI-M 87-053, 140 Pages, 1987/03
no abstracts in English
