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Handa, Yuichi; Nakajima, Ryota; Yonekawa, Akihisa*; Takatsu, Kazuki; Kinoshita, Junichi; Irie, Hirobumi; Suzuki, Hisao*
JAEA-Technology 2020-005, 22 Pages, 2020/06
The Evaporator-II is installed in Waste Treatment Facility No.2. The evaporator system treats intermediate level radioactive liquid waste for Nuclear Science Research Institute and more. It is maintenance the evaporator can once/3years by the maintenance plan. The evaporator can is important unit of the Evaporator-II system. This report summarizes record of maintenance the Evaporator-II in FY2015.
Kitatani, Fumito; Tsuchiya, Harufumi; Toh, Yosuke; Hori, Junichi*; Sano, Tadafumi*; Takahashi, Yoshiyuki*; Nakajima, Ken*
KURRI Progress Report 2017, P. 99, 2018/08
Nakajima, Kenji; Kawakita, Yukinobu; Ito, Shinichi*; Abe, Jun*; Aizawa, Kazuya; Aoki, Hiroyuki; Endo, Hitoshi*; Fujita, Masaki*; Funakoshi, Kenichi*; Gong, W.*; et al.
Quantum Beam Science (Internet), 1(3), p.9_1 - 9_59, 2017/12
The neutron instruments suite, installed at the spallation neutron source of the Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC), is reviewed. MLF has 23 neutron beam ports and 21 instruments are in operation for user programs or are under commissioning. A unique and challenging instrumental suite in MLF has been realized via combination of a high-performance neutron source, optimized for neutron scattering, and unique instruments using cutting-edge technologies. All instruments are/will serve in world-leading investigations in a broad range of fields, from fundamental physics to industrial applications. In this review, overviews, characteristic features, and typical applications of the individual instruments are mentioned.
Kawasaki, Masatsugu; Nakajima, Junya; Yoshida, Keisuke; Kato, Saori; Nishino, Sho; Nozaki, Teo; Nakagawa, Masahiro; Tsunoda, Junichi; Sugaya, Yuki; Hasegawa, Rie; et al.
JAEA-Data/Code 2017-004, 57 Pages, 2017/03
In emergency situation of nuclear facilities, we need to estimate the radiation dose due to radiation and radioactivity to grasp the influence range of the accident in the early stage. Therefore, we prepare the case studies of dose assessment for public exposure dose and personal exposure dose and contribute them to emergency procedures. This document covers about accidents of nuclear facilities in Nuclear Science Research Institute and past accident of nuclear power plant, and it can be used for inheritance of techniques of emergency dose assessment.
Takemoto, Noriyuki; Imaizumi, Tomomi; Kimura, Nobuaki; Tsuchiya, Kunihiko; Hori, Junichi*; Sano, Tadafumi*; Nakajima, Ken*
Proceedings of International Conference on the Physics of Reactors; The Role of Reactor Physics toward a Sustainable Future (PHYSOR 2014) (CD-ROM), 11 Pages, 2014/09
Neutronic evaluations in JMTR have been performed for irradiation tests by Monte Carlo method with thermal neutron scattering law, S(, ), data for beryllium metal, etc. The calculation accuracy of fast and thermal neutron fluxes are 10% and 30%, respectively. Analytical and experimental investigations to achieve higher calculation accuracy, especially for the thermal neutron flux up to the fast neutron flux level, have been therefore performed to offer higher value data technically to the JMTR users. In order to investigate an effect of fabrication method of beryllium material on the calculation accuracy, total cross-sections of beryllium specimens were measured using KURRI-LINAC, and it was found that the total cross-section was different from the theoretical one, and depended on the crystal texture, etc. The S(, ) was adjusted based on the measured data, and the applicability to the neutronic evaluation in the JMTR was verified.
Nakamura, Mitsutaka; Kambara, Wataru; Krist, T.*; Shinohara, Takenao; Ikeuchi, Kazuhiko*; Arai, Masatoshi; Kajimoto, Ryoichi; Nakajima, Kenji; Tanaka, Hiromichi; Suzuki, Junichi*; et al.
Nuclear Instruments and Methods in Physics Research A, 737, p.142 - 147, 2014/02
Times Cited Count:3 Percentile:27.01(Instruments & Instrumentation)The efficiency of inelastic neutron scattering measurements using a chopper spectrometer can be markedly improved by utilizing multiple incident energies (Multi-Ei method). However, in conventional chopper systems, optimization of the experimental condition for all incident energies is absolutely impossible. We developed a new Fermi chopper with a supermirror-coated slit package in order to overcome the problem and experimentally demonstrated that the full optimization of the experimental condition for multiple incident energies is nearly achieved.
Nakajima, Ken*; Iwamoto, Osamu; Hori, Junichi*; Iwamoto, Nobuyuki; Nakamura, Shoji; Koura, Hiroyuki
JAEA-Conf 2013-002, 202 Pages, 2013/10
The 2012 symposium on Nuclear Data organized by the Nuclear Data Division of Atomic Energy Society of Japan (AESJ) and Research Reactor Institute, Kyoto University (KURRI) was held at Kumatori, KURRI on Nov. 15th and 16th, 2012 in cooperation with Nuclear Science and Engineering Directorate of Japan Atomic Energy Agency. The symposium was devoted for presentations and discussions on the four topics: "Nuclear Power after Fukushima Nuclear Plant Accident", "Application of Nuclear Data", "How Should We Deal with Covariances of Nuclear Data?" and "Validation of JENDL-4.0 and Future", as well as poster sessions on various research fields. Tutorials on neutron resonance capture and transmission analysis, international trend of nuclear data research were also given in the symposium. Talks as well as posters presented at the symposium aroused lively discussions among approximately 83 participants. This report consists of total 35 papers including 13 oral presentations and 22 poster presentations.
Umeda, Koji; Kusano, Tomohiro; Ninomiya, Atsushi*; Asamori, Koichi; Nakajima, Junichi*
Journal of Asian Earth Sciences, 73, p.95 - 102, 2013/09
Times Cited Count:4 Percentile:12.3(Geosciences, Multidisciplinary)A linear zone with high strain rates along the Japan Sea coast, the Niigata-Kobe Tectonic Zone (NKTZ), is considered to be associated with rheological heterogeneities in the lower crust and/or upper mantle. Helium isotope variations along the NKTZ reveal a close association with the geophysical evidence for rheological heterogeneities in the crust and mantle. In the northern NKTZ where two large inland earthquakes occurred recently, there appear to be many samples with He/He ratios significantly higher than those observed in the fore-arc side of northeast Japan. A plausible source of mantle helium could be attributed to upward mobilization of aqueous fluids generated by dehydration of the subducting Pacific Plate slab.
Arai, Masatoshi; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; Nakajima, Kenji; Shibata, Kaoru; Takahashi, Nobuaki; Suzuki, Junichi*; Takata, Shinichi; Yamada, Takeshi*; et al.
Journal of the Physical Society of Japan, 82(Suppl.A), p.SA024_1 - SA024_14, 2013/01
Times Cited Count:7 Percentile:47.49(Physics, Multidisciplinary)The paper describes developments of neutron scattering instruments in J-PARC neutron facility, which is a short pulse spallation source operated at a repetition rate 25 Hz and has a proton power 1 MW. New concept has been adopted to utilize high intensity coupled moderator even for a high resolution inelastic scattering instruments by taking a pulse shaping chopper system. Advanced technique has been also realized by taking an ability of event-recording system altogether with an improvement of a chopper system, realizing multi-Ei method. The paper also touches upon a general design concept for diffractometers in accordance with the source characteristics.
Nomi, Takayoshi; Nagatani, Taketeru; Ninagawa, Junichi; Nakajima, Shinji; Maruyama, Hajime; Asano, Takashi; Fujiwara, Shigeo
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-32-Kai Nenji Taikai Rombunshu (Internet), 8 Pages, 2011/11
The IS approach for the JNC-1 site was implemented in August 2008, and this was the first experience in the world. This IS approach aimed not only to improve efficiency and effectiveness of safeguards but also to reduce burden of the plant operation by improvement of efficiency of the inspection activity. It was planned to review effectiveness of this new approach after three years from implementation. And JAEA also evaluated effects by application of the IS approach for two MOX fuel facilities in the JNC-1 site based on the three years experiences from the operator's view point. As the result of evaluation, it was confirmed that there were some difference of benefits by application of the IS approach depending on features of the facility, automation level of equipment and advance level of safeguards systems.
Ninagawa, Junichi; Asano, Takashi; Nagatani, Taketeru; Nakajima, Shinji; Nomi, Takayoshi; Fujiwara, Shigeo
Proceedings of INMM 52nd Annual Meeting (CD-ROM), 8 Pages, 2011/07
Japan was transferred to the Integrated Safeguards (IS) scheme in September 2004. The IS approach for JNC-1 site, including PFPF, was developed to improve the efficiency of safeguards while maintaining the effectiveness and has been implemented since August 2008. JAEA has evaluated the validity of the IS approach for PFPF based on the historical performance over about three-year period. As the result of evaluation, JAEA confirmed the improvement of efficiency of inspection activities and the reduction of the impact of inspection activities on plant operation. On the other hand, the IAEA has also evaluated the validity of IS approach and considered to modify based on the result of its evaluation. In order to maintain or improve the validity of the IS approach, JAEA thinks that it will be necessary to work very closely and honestly with the inspectorate to address this modification process.
Umeda, Koji; Ninomiya, Atsushi; Shimada, Koji; Nakajima, Junichi*
Lithosphere; Geochemistry, Geology and Geophysics, p.141 - 169, 2008/10
A linear zone with high strain rates along the Sea of Japan coast, the Niigata-Kobe Tectonic Zone (NKTZ), is considered to be associated with rheological heterogeneity in the lower crust and/or upper mantle, which may be caused by the upwelling of aqueous fluid and/or melt related to subduction of the Philippine Sea and Pacific Plates. In order to elucidate the geographic distribution of He/He ratios along the NKTZ, new helium isotope data from hot spring gases and water samples were determined. Our study reinforces the clear relationship between helium isotope variations on the surface and the seismicity and resistivity structure of the crust and upper mantle along the Niigata-Kobe Tectonic Zone, Central Japan. In addition, the helium isotopes in hot spring gases may be recognized as a useful geochemical indicator of the presence of concealed active faults with compressional tectonics.
Iwai, Takashi; Nakajima, Kunihisa; Kikuchi, Hironobu; Honda, Junichi; Hatakeyama, Yuichi; Ono, Katsuto; Matsui, Hiroki; Arai, Yasuo
JAEA-Research 2007-026, 75 Pages, 2007/03
A plutonium nitiride fuel pin containing inert matrix such as ZrN and TiN was encapsuled in 01F-51A and irradiated in JMTR. Minor actinides are surrogated by plutonium. Average linear powers and burnups were 408W/cm, 30000MWd/t(Zr+Pu)(132000MWd/t-Pu) for (Zr,Pu)N and 355W/cm, 38000MWd/t(Ti+Pu)(153000MWd/t-Pu) for (TiN,PuN). The irradiated capsule was transported to Reactor Fuel Examination Facility and subjected to non-destructive and destructive post irradiation examinations. Any failure was not observed in theirradiated fuel pin. Very low fission gas release rate of about 1.6% was measured. The inner surface of cladding tube did not show any signs of chemical interaction with fuel pellets.
Ninagawa, Junichi; Asano, Takashi; Fujiwara, Shigeo; Takahashi, Saburo; Menlove, H.*; Rael, C. D.*; Nakajima, Shinji*; Sato, Takashi*
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-27-Kai Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2006/00
no abstracts in English
The Working Team for Examination of the Sample from Core Shrouds and Primary Loop Recirculation Pipi; Nakajima, Hajime*; Shibata, Katsuyuki; Tsukada, Takashi; Suzuki, Masahide; Kiuchi, Kiyoshi; Kaji, Yoshiyuki; Kikuchi, Masahiko; Ueno, Fumiyoshi; Nakano, Junichi; et al.
JAERI-Tech 2004-015, 114 Pages, 2004/03
The Tokyo Electric Power Company (TEPCO) visually inspected the weld joint of core shroud at Fukushima Dai-ni Nuclear Power Station Unit-2 by a direction of the Nuclear and Industrial Agency, cracks were observed at outer side of the ring weld joint (H3) between a core shroud middle trunk and a middle ring. TEPCO has conducted a material examination with Nippon Nuclear Fuel Development Co. Ltd. (NFD) on the specimen including cracks sampled from the core shroud. The present examination has been performed with the objective to independently investigate and evaluate the materials by jointly attending the examination with NFD from the planning stage. Based on results of the present examination, the probable presence of tensile residual stress by welding process and dissolved oxygen contents in the cooling water, it was shown that the cracks were considered to be stress corrosion cracking (SCC). However, the cause of the cracks needs more consideration on the way of shroud construction.
Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.
Nuclear Fusion, 44(2), p.329 - 334, 2004/02
no abstracts in English
Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.
Nuclear Fusion, 44(2), p.329 - 334, 2004/02
Times Cited Count:7 Percentile:22.95(Physics, Fluids & Plasmas)no abstracts in English
Kaji, Yoshiyuki; Miwa, Yukio; Tsukada, Takashi; Kikuchi, Masahiko; Kita, Satoshi; Yonekawa, Minoru; Nakano, Junichi; Tsuji, Hirokazu; Nakajima, Hajime
Journal of Nuclear Materials, 307-311(Part1), p.331 - 334, 2002/12
Times Cited Count:5 Percentile:34.58(Materials Science, Multidisciplinary)Irradiation assisted stress corrosion cracking (IASCC) caused by simultaneous effects of neutron irradiation and high temperature water environments has been pointed out as one of the major concerns of in-core structural materials not only for the light water reactors (LWRs) but also for the water-cooled fusion reactor. It is necessary to evaluate precisely stress condition under irradiation environment, because stress is one of key factors on IASCC. Stress relaxation of tensile type specimens under fast neutron irradiation at 288C has been studied for type 316L stainless steel in Japan Materials Testing Reactor (JMTR). This paper describes the in-pile and out-of-pile stress-relaxation test results of tensile type specimens for type 316L stainless steel as compared with the literature data by Foster, which were mainly obtained by bent beam specimens. Moreover these experimental results were compared with the analytical ones by using Nakagawa's model.
Shibata, Keiichi; Kawano, Toshihiko*; Nakagawa, Tsuneo; Iwamoto, Osamu; Katakura, Junichi; Fukahori, Tokio; Chiba, Satoshi; Hasegawa, Akira; Murata, Toru*; Matsunobu, Hiroyuki*; et al.
Journal of Nuclear Science and Technology, 39(11), p.1125 - 1136, 2002/11
Times Cited Count:669 Percentile:96.97(Nuclear Science & Technology)Evaluation for JENDL-3.3 has been performed by considering the accumulated feedback information and various benchmark tests of the previous library JENDL-3.2. The major problems of the JENDL-3.2 data were solved by the new library: overestimation of criticality values for thermal fission reactors was improved by the modifications of fission cross sections and fission neutron spectra for U; incorrect energy distributions of secondary neutrons from important heavy nuclides were replaced with statistical model calculations; the inconsistency between elemental and isotopic evaluations was removed for medium-heavy nuclides. Moreover, covariance data were provided for 20 nuclides. The reliability of JENDL-3.3 was investigated by the benchmark analyses on reactor and shielding performances. The results of the analyses indicate that JENDL-3.3 predicts various reactor and shielding characteristics better than JENDL-3.2.
Yoshida, Tadashi*; Okajima, Shigeaki; Sakurai, Takeshi; Nakajima, Ken; Yamane, Tsuyoshi; Katakura, Junichi; Tahara, Yoshihisa*; Zukeran, Atsushi*; Oyamatsu, Kazuhiro*; Osawa, Takaaki*; et al.
Journal of Nuclear Science and Technology, 39(Suppl.2), p.136 - 139, 2002/08
no abstracts in English