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Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*
JAEA-Review 2022-063, 86 Pages, 2023/02
The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2021. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station (1F), Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "The study of oxidative stress status in the organs exposed to low dose/low dose-rate radiation" conducted from FY2019 to FY2021. Since the final year of this proposal was FY2021, the results for three fiscal years were summarized. The present study aims to investigate the biological effects of low dose/low dose-rate radiation exposure, which is of great social interest, on the oxidative stress status of individual organs and will contribute to the collection of scientific data in a dose range to be required. The samples to be analyzed in this study were collected from wild Japanese macaques exposed in the ex-evacuation zone after the accident of 1F.
Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*
JAEA-Review 2021-050, 82 Pages, 2022/01
The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "The study of oxidative stress status in the organs exposed to low dose/low dose-rate radiation" conducted in FY2020. The present study aims to investigate the biological effects of low dose/low dose-rate radiation exposure, which is of great social interest, on the oxidative stress status of individual organs and will contribute to the collection of scientific data in a dose range to be required. An interdisciplinary collaborative study discussed the correlation between radiation dose and the biological effect by analyzing the samples of wild Japanese macaques exposed to radiation due to the accident of Fukushima Daiichi Nuclear Power Station and of animal experiments.
Collaborative Laboratories for Advanced Decommissioning Science; Tohoku University*
JAEA-Review 2020-048, 49 Pages, 2021/01
The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2019. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "The study of oxidative stress status in the organs exposed to low dose/low dose-rate radiation". This study investigates the biological effects of low dose/low dose-rate radiation exposure, which is of great social interest, on the oxidative stress status of individual organs and will contribute to the collection of scientific data in a dose range to be required. An interdisciplinary collaborative study discussed the correlation between radiation dose and the biological effect by analyzing the samples of wild Japanese macaques exposed to radiation due to the accident of Fukushima nuclear power station and of animal experiments.
Riyana, E. S.; Okumura, Keisuke; Terashima, Kenichi; Matsumura, Taichi; Sakamoto, Masahiro
Mechanical Engineering Journal (Internet), 7(3), p.19-00543_1 - 19-00543_8, 2020/06
Riyana, E. S.; Okumura, Keisuke; Terashima, Kenichi
Proceedings of 27th International Conference on Nuclear Engineering (ICONE-27) (Internet), 4 Pages, 2019/05
Nagaya, Yasunobu; Okumura, Keisuke; Sakurai, Takeshi; Mori, Takamasa
JAEA-Data/Code 2016-018, 421 Pages, 2017/03
In order to realize fast and accurate Monte Carlo simulation of neutron and photon transport problems, two Monte Carlo codes MVP (continuous-energy method) and GMVP (multigroup method) have been developed at Japan Atomic Energy Agency. The codes have adopted a vectorized algorithm and have been developed for vector-type supercomputers. They also support parallel processing with a standard parallelization library MPI and thus a speed-up of Monte Carlo calculations can be achieved on general computing platforms. The first and second versions of the codes were released in 1994 and 2005, respectively. They have been extensively improved and new capabilities have been implemented. The major improvements and new capabilities are as follows: (1) perturbation calculation for effective multiplication factor, (2) exact resonant elastic scattering model, (3) calculation of reactor kinetics parameters, (4) photo-nuclear model, (5) simulation of delayed neutrons, (6) generation of group constants, etc. This report describes the physical model, geometry description method used in the codes, new capabilities and input instructions.
Shinohara, Masanori; Ishitsuka, Etsuo; Shimazaki, Yosuke; Sawahata, Hiroaki
JAEA-Technology 2016-033, 65 Pages, 2017/01
To reduce the neutron exposure dose for workers during the replacement works of the startup neutron sources of the High Temperature Engineering Test Reactor, calculations of the exposure dose in case of temporary neutron shielding at the bottom of fuels handling machine were carried out by the PHITS code. As a result, it is clear that the dose equivalent rate due to neutron radiation can be reduced to about an order of magnitude by setting a temporary neutron shielding at the bottom of shielding cask for the fuel handling machine. In the actual replacement works, by setting temporary neutron shielding, it was achieved that the cumulative equivalent dose of the workers was reduced to 0.3 man mSv which is less than half of cumulative equivalent dose for the previous replacement works; 0.7 man mSv.
Iwamoto, Yosuke; Taniguchi, Shingo*; Nakao, Noriaki*; Itoga, Toshio*; Nakamura, Takashi*; Nakane, Yoshihiro; Nakashima, Hiroshi; Satoh, Daiki; Yashima, Hiroshi*; Yamakawa, Hiroshi*; et al.
Nuclear Instruments and Methods in Physics Research A, 562(2), p.789 - 792, 2006/06
Times Cited Count:7 Percentile:46.37(Instruments & Instrumentation)Neutron energy spectra produced from thick targets play an important role in validation of calculation codes that are employed in the design of spallation neutron sources and the shielding design of accelerator facilities. However, appropriate experimental data were scarce in the forward direction for the incident energy higher than 100 MeV. In this study, neutron spectra at 0 degree from thick targets bombarded with 350 MeV protons were measured by the time-of-flight technique using an NE213. The targets used were graphite, Al, Fe and Pb and their thicknesses were chosen to be a little thicker than the stopping lengths. The experiment was carried out at the TOF course of the RCNP (Research Center of Nuclear Physics) ring cyclotron, Osaka University. The flight path length between center of the target and of an NE213 were 11.4 m for the measurement of low energy neutrons and 95 m for high energy neutrons. The experimental data are compared with the calculated results by using the Monte Carlo transport codes, such as MCNPX and PHITS codes.
Takase, Haruhiko*; Tobita, Kenji; Nishio, Satoshi
JAERI-Data/Code 2003-013, 46 Pages, 2003/08
no abstracts in English
Yoshizawa, Michio; Endo, Akira
JAERI-Conf 2003-002, 166 Pages, 2003/03
The present report is Proceedings of the Third Workshop on Dosimetry for External Radiations, held at the Tokai Research Establishment, Japan Atomic Energy Research Institute (JAERI), in November 28-29, 2002. The proceedings comprises 16 papers and a summary of general discussion. The Third Workshop, subtitled "On an opportunity of the completion of the facility of calibration standards for neutron at JAERI", focused on neutron dosimetry and included presentations on the status of international neutron standards, the development of calibration techniques of neutron dosimeters using accelerator neutron sources, and dosimetry for high-energy neutrons. The workshop identified the directions for the future research and development in this field.
Ikeda, Yujiro
Journal of Nuclear Science and Technology, 39(Suppl.2), p.13 - 18, 2002/08
no abstracts in English
Tamai, Hiroshi; Ishida, Shinichi; Kurita, Genichi; Sakamoto, Yoshiteru; Fujita, Takaaki; Shirai, Hiroshi; Tsuchiya, Katsuhiko; Matsukawa, Makoto; Sakasai, Akira; Sakurai, Shinji; et al.
Proceedings of 29th European Physical Society Conference on Plasma Physics and Controlled Fusion, 4 Pages, 2002/00
This paper presents the feasibility and issues of steady state operation with a central current hole for JT-60SC, the superconducting tokamak to be modified from JT-60, from the view of reactor applicability of the current hole. An impact of the current hole on fusion engineering would stand in no necessity of central current drive leading to a remarkable reduction of neutral beam injection energy. The 1.5D time-dependent transport code analysis is made with using thermal and particle transport coefficients deduced from observations in JT-60U as a function of the magnetic shear. A steady state operation with HHy2~1.6 and beta_N~4 is obtained at Ip=1.5 MA, Bt=2 T and q95=4.5 by off-axis beams of 11.2 MW. The bootstrap fraction of ~75% of the plasma current and the current hole region of ~30% of the minor radius are sustained up to 70 s. The results suggest that a bootstrap current evolution near the current hole region and a relation between the location of ITB and the central current hole region are important to achieve a steady state plasma compatible with the current hole.
U Doppler Effect using various samples in FCA XVII-1Ando, Masaki; Okajima, Shigeaki; Oigawa, Hiroyuki
JAERI-Research 2001-017, 20 Pages, 2001/03
U Doppler effect measurements were carried out using 6 uranium samples with various composition or diameter varying self-shielding factors of
U. Calculation accuracy of the standard analysis method for fast reactor cores at FCA was investigated.The Doppler effect were measured by the sample-heated and reactivity worth measurement method up to 800 degree in the FCA XVII-1 assembly, which simulated Na-cooled MOX fueled FBR. In the analysis, the Doppler effect was calculated using the effective cross sections obtained by the PEACO-X code. The calculated values based on the diffusion theory agreed well with the experiment for the U-metal and UO
samples. The calculation underestimated the experiment from 10% to 30% for the UO
samples containing BeO. This underestimation was improved by the use of the transport calculation. The calculation, however, underestimated about 20% for the sample whose background cross section is greater than 300 barns.
Takada, Hiroshi; Meigo, Shinichiro; Niita, Koji*
Advanced Monte Carlo for Radiation Physics, Particle Transport Simulation and Applications, p.949 - 954, 2001/00
no abstracts in English
line spectral profile and emission process in the divertor region of JT-60UKumagai, Akira*; Kubo, Hirotaka; Takenaga, Hidenobu; Suzuki, Shingo; Shimizu, Katsuhiro; Asakura, Nobuyuki; Shimada, Michiya
Plasma Physics and Controlled Fusion, 42(5), p.529 - 543, 2000/05
Times Cited Count:13 Percentile:38.59(Physics, Fluids & Plasmas)no abstracts in English
Yamagiwa, Mitsuru; ; M.Elia*
Physics of Plasmas, 4(11), p.4031 - 4034, 1997/11
Times Cited Count:2 Percentile:8.51(Physics, Fluids & Plasmas)no abstracts in English
Yamagiwa, Mitsuru; ; M.Elia*
PPL-167, p.1 - 13, 1997/08
no abstracts in English
; ; Suzuki, Tomoo*
JAERI-Data/Code 96-021, 33 Pages, 1996/06
no abstracts in English
Okumura, Keisuke; ;
JAERI-Data/Code 96-015, 445 Pages, 1996/03
no abstracts in English
; ;
PATRAM 95: 11th Int. Conf. on the Packaging and Transportation of Radioactive Materials, 3, p.1174 - 1181, 1996/00
no abstracts in English