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Tanaka, Taiki*; Narikiyo, Yoshihiro*; Morita, Kosuke*; Fujita, Kunihiro*; Kaji, Daiya*; Morimoto, Koji*; Yamaki, Sayaka*; Wakabayashi, Yasuo*; Tanaka, Kengo*; Takeyama, Mirei*; et al.
Journal of the Physical Society of Japan, 87(1), p.014201_1 - 014201_9, 2018/01
Times Cited Count:20 Percentile:74.66(Physics, Multidisciplinary)Excitation functions of quasielastic scattering cross sections for the Ca + Pb, Ti + Pb, and Ca + Cm reactions were successfully measured by using the gas-filled recoil-ion separator GARIS. Fusion barrier distributions were extracted from these data, and compared with the coupled-channels calculations. It was found that the peak energies of the barrier distributions for the Ca + Pb and Ti + Pb systems coincide with those of the 2n evaporation channel cross sections for the systems, while that of the Ca + Cm is located slightly below the 4n evaporation ones. This results provide us helpful information to predict the optimum beam energy to synthesize superheavy nuclei.
Oe, Kazuhiro*; Attallah, M. F.*; Asai, Masato; Goto, Naoya*; Gupta, N. S.*; Haba, Hiromitsu*; Huang, M.*; Kanaya, Jumpei*; Kaneya, Yusuke*; Kasamatsu, Yoshitaka*; et al.
Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1317 - 1320, 2015/02
Times Cited Count:10 Percentile:62.42(Chemistry, Analytical)A new technique for continuous dissolution of nuclear reaction products transported by a gas-jet system was developed for superheavy element (SHE) chemistry. In this technique, a hydrophobic membrane is utilized to separate an aqueous phase from the gas phase. With this technique, the dissolution efficiencies of short-lived radionuclides of Mo and W were measured. Yields of more than 80% were observed for short-lived radionuclides at aqueous-phase flow rates of 0.1-0.4 mL/s. The gas flow-rate had no influence on the dissolution efficiency within the studied flow range of 1.0-2.0 L/min. These results show that this technique is applicable for on-line chemical studies of SHEs in the liquid phase.
Ishihara, Masahiro; Kimura, Nobuaki; Takemoto, Noriyuki; Ooka, Makoto; Kaminaga, Masanori; Kusunoki, Tsuyoshi; Komori, Yoshihiro; Suzuki, Masahide
Proceedings of 5th International Symposium on Material Testing Reactors (ISMTR-5) (Internet), 7 Pages, 2012/10
The JMTR has been utilized for fuel/material irradiation examinations of LWRs, HTGR, fusion reactor as well as for RI productions. The refurbishment of the JMTR was started from the beginning of JFY 2007, and finished in March 2011 as planned schedule. Unfortunately, at the end of the JFY 2010 on March 11, the Great-Eastern-Japan-Earthquake occurred, and functional tests before the JMTR restart were delayed by the earthquake. Moreover, a detail inspection found some damages such as small cracks in the concrete structure, ground sinking around the reactor building. Consequently, the restart will delay from June 2011. Now, the safety evaluation of the facility after the earthquake disaster is being carried out aiming at the restart of the JMTR. The renewed JMTR will be started from JFY 2012 and operated for a period of about 20 years until around JFY 2030. The usability improvement of the JMTR is also discussed with users as the preparations for re-operation.
Takamatsu, Kuniyoshi; Sawa, Kazuhiro; Kunitomi, Kazuhiko; Hino, Ryutaro; Ogawa, Masuro; Komori, Yoshihiro; Nakazawa, Toshio*; Iyoku, Tatsuo; Fujimoto, Nozomu; Nishihara, Tetsuo; et al.
Nihon Genshiryoku Gakkai Wabun Rombunshi, 10(4), p.290 - 300, 2011/12
A high temperature (950C) continuous operation has been performed for 50 days on the HTTR from January to March in 2010, and the potential to supply stable heat of high temperature for hydrogen production for a long time was demonstrated for the first time in the world. This successful operation could establish technological basis of HTGRs and show potential of nuclear energy as heat source for innovative thermo-chemical-based hydrogen production, emitting greenhouse gases on a "low-carbon path" for the first time in the world.
Takada, Shoji; Nishihara, Tetsuo; Iyoku, Tatsuo; Nakazawa, Toshio; Komori, Yoshihiro
Nihon Genshiryoku Gakkai-Shi ATOMO, 52(7), P. 387, 2010/07
The 50-day long-term high-temperature operation was successfully attained by the High Temperature Engineering Test Reactor (HTTR) of the Japan Atomic Energy Agency (JAEA), the rated thermal output of 30 MW and the maximum reactor outlet temperature of 950 C, first in the world. The operation was started on January 22 and accomplished on March 13 this year. Many data on the characteristics of reactor core physics and thermal hydraulics, the impurity control in coolant helium gas, the performance of high temperature components and the core internal structure integrity was acquired to establish the HTGR technology basis. The HTGR is expected as a green-house gas emission free heat source of innovative thermo-chemical hydrogen production system. It was demonstrated first in the world that high temperature gas can be stably supplied for long term period. In the next stage, the tests will be carried out to confirm the applicability and the extreme safety performance of HTGR by the HTTR.
Iigaki, Kazuhiko; Goto, Minoru; Tachibana, Yukio; Iyoku, Tatsuo; Komori, Yoshihiro
Koon Gakkai-Shi, 32(1), p.3 - 10, 2006/01
no abstracts in English
Sakaba, Nariaki; Tachibana, Yukio; Onuki, Kaoru; Komori, Yoshihiro; Ogawa, Masuro
Nuclear Engineering International, 50(612), p.20 - 22, 2005/07
The HTTR (High Temperature Engineering Test Reactor) at Japan Atomic Energy Research Institute's Oarai Research Establishment attained its maximum reactor-outlet coolant temperature of 950C in April 2004 and ready to connect nuclear heat for industrial applications. The hydrogen production system by thermochemical water-splitting Iodine Sulphur cycle is also developing and succeeded to produce 30 normal L/h hydrogen in a closed cycle in June 2004.
Shiozawa, Shusaku; Komori, Yoshihiro; Ogawa, Masuro
Nihon Genshiryoku Gakkai-Shi, 47(5), p.342 - 349, 2005/05
For the purpose to extend high temperature nuclear heat application, JAERI constructed the HTTR, High Temperature Engineering Test Reactor, and has carried out research and development of high temperature gas cooled reactor system aiming at high efficiency power generation and hydrogen production. This paper explains the history, main results, present status of research and development of HTTR project, international cooperation of research and development of HTGR and future plan aiming at development of Japanese original future HTGR-Hydrogen production system. This paper includes results from the study, which is entrusted from Ministry of Education, Culture, Sports, Science and Technology of Japan.
Hayashi, Hideyuki; Sawa, Kazuhiro; Komori, Yoshihiro
Proceedings of International Symposium on Research Reactor and Neutron Science; In Commemoration of the 10th Anniversary of HANARO (HANARO 2005), p.215 - 220, 2005/04
Irradiation experiments for the HTTR fuel development were performed mostly by using Oarai Gas Loop-1 (OGL-1) and capsules in Japan Material Test Reactor (JMTR) of JAERI. Various kinds of researches have been carried out to confirm the integrity of the HTTR fuel. Present status and future plan of the HTTR project were also outlined.
Ide, Hiroshi; Matsui, Yoshinori; Nagao, Yoshiharu; Komori, Yoshihiro; Itabashi, Yukio; Tsuji, Hirokazu; Tsukada, Takashi; Nagata, Nobuaki*; Dozaki, Koji*; Takiguchi, Hideki*
Proceedings of 11th International Conference on Nuclear Engineering (ICONE-11) (CD-ROM), 7 Pages, 2003/04
The advanced water chemistry controlled irradiation research device has been developed in JAERI to perform irradiation tests for research on IASCC. The irradiation device consists of the SATCAP (Saturated Temperature Capsule) inserted into the JMTR core and the water control unit installed out-of-core. Regarding the SATCAP, thermohydraulic design of the SATCAP was performed aiming at controlling the specimen temperature with high accuracy and increasing water flow velocity on the specimen surface to improve the controllability of water chemistry. As a result of irradiation test using the new type SATCAP, each specimen temperature and water chemistry were able to be controlled as designed.
Ide, Hiroshi; Matsui, Yoshinori; Itabashi, Yukio; Komori, Yoshihiro; Nagao, Yoshiharu; Komukai, Bunsaku; Tsuji, Hirokazu; Akimoto, Hajime; Onuki, Akira; Araya, Fumimasa
JAERI-Tech 2002-079, 58 Pages, 2002/10
no abstracts in English
Komori, Yoshihiro; Matsui, Yoshinori; Itabashi, Yukio; Yamaura, Takayuki; Nagao, Yoshiharu
KAERI/GP-195/2002, p.59 - 69, 2002/00
JAERI has been developing irradiation technique and facilities for irradiation tests in the JMTR to improve irradiation capability keeping up with progress of nuclear fuels and materials research. This paper summarizes recent development on irradiation technique for the JMTR. Design study and installation of the IASCC (Irradiation Assisted Stress Corrosion Cracking) irradiation test facility was main and the most urgent task of the field in the last five years since two large projects for IASCC were planned in Japan to start irradiation tests in 2002. Almost four years were devoted to preliminary design study, detail design and installation of the facility, then IASCC irradiation test started in March, 2002. Instrumentation technique and capsules development for other research purposes also have been steadily progressing during the term, and new type of off-line temperature monitor, dual re-instrumentation device and the uniform irradiation capsule became available for the irradiation tests.
Komori, Yoshihiro; Amezawa, Hiroo; Komukai, Bunsaku; Narui, Minoru*; Konashi, Kenji*
KAERI/GP-195/2002, p.3 - 10, 2002/00
The actinide-hydride(UThZrH) fuel has been studied for transmutation of long-lived actinide contained in the high level wastes and the first irradiation test was successfully carried out in the Japan Materials Testing Reactor (JMTR) of JAERI. Fuel pellets were fabricated by alloying and hydrogenation within an expected diameter error. The fuel pellets were designed to be irradiated below 873K on the fuel surface in consideration of hydrogen dissociation. Irradiation temperature was well agreed with designed value. Fuel burnup reached 0.2%FIMA for two JMTR operation cycles.
Nagao, Yoshiharu; Itabashi, Yukio; Komori, Yoshihiro; Niimi, Motoji; Fujiki, Kazuo
KAERI/GP-195/2002, p.49 - 55, 2002/00
An improved analysis procedure has been introduced to evaluate irradiation field at each specimen in the irradiation capsule by using the MCNP code, which is able to model the complicated structure of the capsule directly. As the verification results, it was confirmed that the calculated fast and thermal neutron flux/fluence were agreed with measured ones within 10% and 30%, respectively, for the irradiation tests in the JMTR. Concerning gamma dose/spectrum, it was confirmed that the calculated temperature was evaluated within -3+14% using gamma heating obtained by MCNP calculations. The evaluations of neutron flux/fluence and specimens temperature with high accuracy are therefore possible in the irradiation test of the JMTR.
Tsukada, Takashi; Komori, Yoshihiro; Tsuji, Hirokazu; Nakajima, Hajime; Ito, Haruhiko
Proceedings of International Conference on Water Chemistry in Nuclear Reactor Systems 2002 (CD-ROM), 5 Pages, 2002/00
Irradiation assisted stress corrosion cracking (IASCC) is caused by the synergistic effects of neutron and gamma radiation, residual and applied stresses and high temperature water environment on the structural materials of vessel internals. IASCC has been studied since the beginning of the 1980s and the phenomenological knowledge on IASCC is accrued extensively. However, mainly due to the experimental difficulties, data for the mechanistic understanding and prediction of failures of the specific in-vessel components are still insufficient and further well-controlled experiments are needed [1]. In recent years, efforts to perform the in-pile materials test for IASCC study have been made at some research reactors [2-4]. At JAERI, a high temperature water loop facility was designed to install at the Japan Materials Testing Reactor (JMTR) to carry out the in-core IASCC testing. This report describes an overview of design and specification of the loop facility.
Kanno, Masaru; Nabeya, Hideaki; Mori, Yuichiro*; Matsui, Yoshinori; Tobita, Masahiro*; Ide, Hiroshi; Itabashi, Yukio; Komori, Yoshihiro; Tsukada, Takashi; Tsuji, Hirokazu
JAERI-Tech 2001-080, 57 Pages, 2001/12
no abstracts in English
Komori, Yoshihiro
Saishin Kaku Nenryo Kogaku; Kodoka No Genjo To Tembo, p.241 - 250, 2001/06
no abstracts in English
Toyoshima, Atsushi; Asai, Masato; Attallah, M. F.*; Goto, Naoya*; Gupta, N. S.*; Haba, Hiromitsu*; Huang, M.*; Kanaya, Jumpei*; Kaneya, Yusuke; Kasamatsu, Yoshitaka*; et al.
no journal, ,
Towards electrolytic reduction of Sg, batch-wise electrolytic reduction of carrier-free Mo and W radiotracers was studied using a flow electrolytic column (FEC). The electrolyzed samples from a FEC were chemically analyzed by solvent extraction with TOA and HDEHP to separate and identify reduced species from the stable Mo(VI) and W(VI) ones based on their different extraction behavior. Mo and W were applied as radiotracers. We also performed cyclic voltammetry and UV/Vis absorption spectrometry of macro amounts of Mo and W in acidic solutions to obtain information on redox reactions of these elements under given conditions. In the conference, the present status of the preparatory reduction experiments with Mo and W will be presented.
Sato, Junya; Suzuki, Shinji*; Kato, Jun; Sakakibara, Tetsuro; Nakazawa, Osamu; Meguro, Yoshihiro; Ueda, Hiroshi*; Kurosaki, Fumio*; Yoneyama, Takashi*; Matsukura, Minoru*; et al.
no journal, ,
no abstracts in English
Kurosaki, Fumio*; Ueda, Hiroshi*; Yoneyama, Takashi*; Matsukura, Minoru*; Mimura, Hitoshi*; Sato, Junya; Nakazawa, Osamu; Meguro, Yoshihiro; Mori, Koichi*; Komori, Hideyuki*
no journal, ,
no abstracts in English