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Nishida, Akemi
Doboku Gakkai Dai-14-Kai Kozobutsu No Shogeki Mondai Ni Kansuru Shinpojiumu Rombunshu (Internet), 5 Pages, 2024/01
no abstracts in English
Tazaki, Makiko; Kimura, Takashi; Shimizu, Ryo; Tamai, Hiroshi; Nakatani, Takayoshi; Suda, Kazunori
JAEA-Review 2022-056, 54 Pages, 2023/01
JAEA-Review-2022-056.pdf:1.86MB
As part of the "Research on Factor Analysis and Technical Processes for Achieving Denuclearization" South Africa's nuclear development and denuclearization cases were investigated then analyzed from seven denuclearization factors namely (1) motivation for nuclear development, (2) internal and external situations at the time of denuclearization decision, (3) progress of nuclear development, (4) effects of sanctions, (5) incentives for denuclearization, (6) international framework for denuclearization, (7) denuclearization and verification methods. At the same time, characteristics of its denuclearization and lessons learned from the denuclearization were also analyzed. South Africa shifted its nuclear activities from research and development of "peaceful nuclear detonation" in the 1970s to developing "limited nuclear deterrence" and finally to manufacturing "transportable nuclear weapons" in the late 1980s. By then, it had completed producing six nuclear explosive devices using highly enriched uranium. However, in 1989, along with the abolition of the apartheid policy, South Africa decided denuclearization and dismantled its nuclear explosive devices and related facilities. Upon completion of dismantlement, it joined the Treaty on the Non- Proliferation of Nuclear Weapons and concluded a Comprehensive Safeguards Agreement (CSA) with the International Atomic Energy Agency (IAEA). The South Africa has remained one of the rare countries that has continued to the peaceful use nuclear energy, and its voluntary denuclearization is considered as a good example of denuclearization in the future.
Wada, Yoriko*; Akagi, Hiroshi*; Kumada, Takayuki; Itakura, Ryuji*; Wakabayashi, Tomonari*
Photochem (Internet), 2(3), p.798 - 809, 2022/09
Coulomb explosion experiments using 60 fs laser pulses were conducted for structural characterization of three dichloroethylene isomers. Under laser intensity at 1.8 
10
W/cm
, mass-resolved momentum imaging (MRMI) for selected fragment ions of 
Cl
and C
revealed different patterns for the three isomers. The C
ion fragmented from multiply charged trans-1,2-DCE was forced to leave perpendicularly to the direction of the laser polarization, due to recoil forces from adjacent cations. In contrast, the fast ions of C from cis-1,2-DCE exhibited an isotropic distribution, whereas the fast ions of C from 1,1-DCE recoiled along the laser polarization together with the slow C ions, and thereby distinction of the three isomers was demonstrated. Coulomb explosion occurs predominantly at specific orientation, which is useful for potential applications of MRMI analysis to molecular structure assays.
Hidaka, Akihide
Proceedings of 2021 International Congress on Advances in Nuclear Power Plants (ICAPP 2021) (USB Flash Drive), 10 Pages, 2021/10
Author recently proposed that the Type A glassy Cesium-bearing microparticles that were released during the Fukushima accident may have been formed by melting and atomization of glass fibers of the High Efficiency Particulate Air (HEPA) filter in the Stand-by Gas Treatment System (SGTS) line in Unit 3 during the hydrogen explosion. In the present study, the components of the Type A and glass fibers of HEPA filter were examined using EPMA. The results showed that the components of the Type A were almost the same as that of the glass fibers except for Cs, Fe, Sn, which are considered to have been contained in the in-vessel-derived particles. When the glass fiber was irradiated with the electron beam of the Electron Probe Micro Analyzer (EPMA) under vacuum condition, spherical particles of a few micro m size were formed that looked very similar to the Type A. These strongly suggest that the HEPA filter is Si source of the Type A.
Hidaka, Akihide
Nihon Genshiryoku Gakkai-Shi ATOMO
, 63(9), p.679 - 680, 2021/09
no abstracts in English
Hino, Ryutaro; Takegami, Hiroaki; Yamazaki, Yukie; Ogawa, Toru
JAEA-Review 2016-038, 294 Pages, 2017/03
JAEA-Review-2016-038.pdf:11.08MB
In the aftermath of the Fukushima nuclear accident, safety measures against hydrogen in severe accident have been recognized as a serious technical problem in Japan. Therefore, efforts have begun to form a common knowledge base between nuclear engineers and experts on combustion and explosion, and to secure and improve future nuclear energy safety. As one of such activities, we have prepared the "Handbook of Advanced Nuclear Hydrogen Safety" under the Advanced Nuclear Hydrogen Safety Research Program funded by the Agency for Natural Resources and Energy of the Ministry of Economy, Trade and Industry. The concepts of the handbook are as follows: to show advanced nuclear hydrogen safety technologies that nuclear engineers should understand, to show hydrogen safety points to make combustion-explosion experts cooperate with nuclear engineers, to expand information on water radiolysis considering the situation from just after the Fukushima accidents and to the waste management necessary for decommissioning after the accident, etc.
Sumiyoshi, Kosuke*; Yamada, Shoichi*; Suzuki, Hideyuki*; Chiba, Satoshi
Physical Review Letters, 97(9), p.091101_1 - 091101_4, 2006/09
Times Cited Count：101 Percentile：93.04(Physics, Multidisciplinary)no abstracts in English
Hayakawa, Takehito; Iwamoto, Nobuyuki; Shizuma, Toshiyuki; Kajino, Toshitaka*; Umeda, Hideyuki*; Nomoto, Kenichi*
European Physical Journal A, 27(S1), p.123 - 128, 2006/03
Times Cited Count：0 Percentile：0.01(Physics, Nuclear)no abstracts in English
Chiba, Atsuya; Saito, Yuichi; Narumi, Kazumasa
JAEA-Review 2005-001, TIARA Annual Report 2004, p.343 - 345, 2006/01
no abstracts in English
Sumiyoshi, Kosuke*; Yamada, Shoichi*; Suzuki, Hideyuki*; Shen, H.*; Chiba, Satoshi; Toki, Hiroshi*
Astrophysical Journal, 629(2, Part1), p.922 - 932, 2005/08
Times Cited Count：228 Percentile：97.41(Astronomy & Astrophysics)no abstracts in English
-process path and its implications for a 
Re-Os nucleo-cosmochronometerHayakawa, Takehito; Shizuma, Toshiyuki; Kajino, Toshitaka*; Chiba, Satoshi; Shinohara, Nobuo; Nakagawa, Tsuneo; Arima, Taiko*
Astrophysical Journal, 628(1, Part1), p.533 - 540, 2005/07
Times Cited Count：22 Percentile：51.52(Astronomy & Astrophysics)no abstracts in English
-process and the 
Lu nuclear cosmochronometerHayakawa, Takehito; Iwamoto, Nobuyuki; Shizuma, Toshiyuki; Kajino, Toshitaka*; Umeda, Hideyuki*; Nomoto, Kenichi*
Nuclear Physics A, 758, p.525c - 528c, 2005/07
no abstracts in English
Usami, Tsutomu; Moriyama, Kiyofumi; Nishikizawa, Tomotoshi; Nakamura, Hideo
JAERI-Tech 2005-028, 37 Pages, 2005/05
JAERI-Tech-2005-028.pdf:16.32MB
The steam explosion during a severe accident in a light water reactor, which may occur by the contact of molten core and coolant, has been known as a potential threat on the integrity of the containment vessel, and has been studied in the nuclear safety research field. Prediction of the intensity of steam explosions needs an understanding of the initial premixture. However, visual observation of the premixture in experiments is usually difficult due to the vapor generation. Thus, we investigated the possibility of a high-speed X-ray visualization with a 4500 f/s high speed video camera with an image-intensifier and three kinds of scintillator materials: CdWO
, ZnS(Ag) and CsI(Tl). A modeled premixture consisted of metal objects and bubbles in a water vessel was used. The test result showed that the CsI(Tl) scintillator gave the best image quality among the three and the high-speed visualization at 4500 f/s was possible, though in the still picture which carried out one of the recorded picture, the picture became indistinct.
Ishii, Yasutomo; Azumi, Masafumi; Kishimoto, Yasuaki
Theory of Fusion Plasmas, ISPP21, p.213 - 226, 2004/00
no abstracts in English
Nishiuchi, Mamiko; Daido, Hiroyuki; Takabe, Hideaki*; Matsukado, Koji*
Reza Kenkyu, 31(11), p.711 - 720, 2003/11
no abstracts in English
Maruyama, Toshiki; Chiba, Satoshi
JAERI-Conf 2003-009, 233 Pages, 2003/08
JAERI-Conf-2003-009.pdf:15.94MB
The fifth symposium on Science of Hadrons under Extreme Conditions, organized by the Research Group for Hadron Science, Advanced Science Research Center, was held at Tokai Research Establishment of JAERI on March 18 to 20, 2003. The symposium was devoted for discussions and presentations of research results in wide variety of hadron physics such as nuclear matter, hypernuclei, neutron stars, supernovae, nucleosynthesis, heavy-ion reactions, quark matter and quantum chromodynamics to understand various aspects of hadrons under extreme conditions. Thirty three papers on these topics presented at the symposium aroused lively discussions among approximately 50 participants. The concluding remark for the "research group for hadron science" and the explanation of next project "research group for manybody theory of hadron systems" was also presented by the group leader Dr. S. Chiba with gratitude to the participants and to all the scientists concerned.
Chimi, Yasuhiro; Iwase, Akihiro; Ishikawa, Norito; Kambara, Tadashi*
Nuclear Instruments and Methods in Physics Research B, 193(1-4), p.248 - 252, 2002/06
Times Cited Count：2 Percentile：18.93(Instruments & Instrumentation)no abstracts in English
Kishimoto, Yasuaki; Masaki, Tomohiro*; Tajima, Toshiki*
Physics of Plasmas, 9(2), p.589 - 601, 2002/02
Times Cited Count：85 Percentile：91.1(Physics, Fluids & Plasmas)no abstracts in English
Sekioka, T.*; Terasawa, Michitaka*; Sataka, Masao; Kitazawa, Shinichi; Niibe, M.*
Nuclear Instruments and Methods in Physics Research B, 193(1-4), p.751 - 754, 2002/01
Times Cited Count：2 Percentile：18.93(Instruments & Instrumentation)no abstracts in English
Miyamoto, Yutaka; Oda, Tetsuzo; Adachi, Takeo; Noguchi, Hiroshi; Nishimura, Hideo; Usuda, Shigekazu
Nukleonika, 46(4), p.123 - 126, 2001/12
no abstracts in English
