Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Collaborative Laboratories for Advanced Decommissioning Science; Osaka University*
JAEA-Review 2023-039, 71 Pages, 2024/03
JAEA-Review-2023-039.pdf:4.43MB
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 FY2021, this report summarizes the research results of the "Improvement of aerosol time-of-flight mass spectrometer for on-line measurement of tiny particles containing alpha emitters" conducted in FY2021. The present study aims to improve Aerosol Time-Of-Flight Mass Spectrometer in order to monitor tiny particles containing alpha emitters such as U and Pu generated in removing debris from the reactors of 1F. In FY2021, for improving mass-resolution, we designed the optimized structure of mass spectrometer with much better mass resolution and ion transmittance than commercial ATOFMS by a PC simulation. Further, design of a detection part of ATOFMS fitted to the mass spectrometer was completed.
Collaborative Laboratories for Advanced Decommissioning Science; Ibaraki University*
JAEA-Review 2023-021, 112 Pages, 2024/02
JAEA-Review-2023-021.pdf:7.1MB
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 FY2018, this report summarizes the research results of the "Contribution to Risk Reduction in Decommissioning Works by the Elucidation of Basic Property of Radioactive Microparticles" conducted from FY2018 to FY2021 (this contract was extended to FY2021). The present study aims to understand the basic properties (size, chemical composition, isotopic composition - including concentration of 
-emitters, electrostatic properties, and optical properties, etc.) of fine particles composed of silicate with insoluble properties which contain regions of highly concentrated radioactive cesium (Cs) released to the environment by the accident at the Fukushima Daiichi Nuclear Power Station of TEPCO in 2011 March.
Collaborative Laboratories for Advanced Decommissioning Science; Osaka University*
JAEA-Review 2021-074, 104 Pages, 2022/03
JAEA-Review-2021-074.pdf:4.91MB
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 "Basic study for on-line monitoring of tiny particles including alpha emitters by aerosol time-of-flight mass spectroscopy" conducted in FY2019 and FY2020. Since the final year of this proposal was FY2020, the results for two fiscal years were summarized. The present study aims to conduct a feasibility study of Aerosol time-of-flight mass spectroscopy (ATOFMS) to on-line measurement of tiny particles containing alpha emitters which might be dispersed in cutting the debris in reactors of the Fukushima Daiichi Nuclear Power Station for realizing their real-time monitoring.
Collaborative Laboratories for Advanced Decommissioning Science; Osaka University*
JAEA-Review 2020-050, 69 Pages, 2021/01
JAEA-Review-2020-050.pdf:3.79MB
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 "Basic study for On-Line Monitoring of Tiny Particles including Alpha Emitters by Aerosol Time-Of-Flight Mass Spectroscopy" conducted in FY2019. The present study aims to conduct a feasibility study of Aerosol Time-Of-Flight Mass Spectroscopy (ATOFMS) technique to on-line measurement of tiny particles including alpha emitters which might be dispersed in cutting debris in reactors of the Fukushima Daiichi Nuclear Power Station for realizing real-time monitoring of the tiny particles. In FY2019, we prepared the solid (U, Zr)O
samples and the acidic and basic U solutions as model materials.
Collaborative Laboratories for Advanced Decommissioning Science; Ibaraki University*
JAEA-Review 2020-033, 84 Pages, 2021/01
JAEA-Review-2020-033.pdf:4.9MB
JAEA/CLADS had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project in FY2019. Among the adopted proposals in FY2018, this report summarizes the research results of the "Contribution to Risk Reduction in Decommissioning Works by the Elucidation of Basic Property of Radioactive Microparticles" conducted in FY2019.
Tani, Keiji; Tobita, Kenji; Nishio, Satoshi; Iio, Shunji*; Tsutsui, Hiroaki*; Aoki, Takayuki*
Purazuma, Kaku Yugo Gakkai-Shi, 80(11), p.931 - 934, 2004/11
Studies were made on ripple losses of fusion produced alpha particles in a low-aspect-ratio tokamak reactor (VECTOR) by using an orbit-following Monte-Carlo code. Alpha particles are well confined in VECTOR. In a low-aspect-ratio tokamak, the dependence of ripple losses on the number of toroidal-field (TF) coils N is very weak. Assuming a toroidal peaking factor of 2 for the heat load due to loss particles, about 1.5% and 1.0% of TF ripple at the outer edge of plasma might be allowable for the first wall with and without cooling system, respectively. In both cases, the number of TF-coils can be reduced to about 4.
-particle diagnostics by CO laser collective Thomson scattering in ITERKondoh, Takashi; Richards, R. K.*; Hutchinson, D. P.*; Sugie, Tatsuo; Costley, A. E.*; Miura, Yukitoshi; Lee, S.*
Proceedings of 30th EPS Conference on Controlled Fusion and Plasma Physics (CD-ROM), 4 Pages, 2003/07
In order to understand the behavior of alpha-particles which are the dominant heat source in a burning plasma, it is necessary to measure the spatial distribution of the number of the alpha-particles and their energy spectrum. A collective Thomson scattering (CTS) system based on a pulsed CO laser is being developed and is under consideration for alpha-particle measurements on ITER. Heating beam ions (E = 1 MeV) are normally co-injected and have a similar velocity with alpha-particles in ITER. The CTS measurement can not, in general, distinguish beam ions and alpha-particles which have the same velocity. A vertical scattering geometry to distinguish between beam ions and alpha-particles is proposed. Calculations have shown that the vertically viewing CTS can resolve counter-travelling alphas without being masked by beam ions. Preliminary design of a beam line and a receiver system with the vertical scattering geometry has been developed. A proof-of-principle test on the CTS system using the JT-60U plasma is being conducted.
laser for ion energy spectrum measurements in JT-60UKondoh, Takashi; Miura, Yukitoshi; Lee, S.*; Richards, R. K.*; Hutchinson, D. P.*; Bennett, C. A.*
Review of Scientific Instruments, 74(3), p.1642 - 1645, 2003/03
Times Cited Count：20 Percentile：68.22(Instruments & Instrumentation)Measurements of energy spectrum and density profile of confined alpha-particles are required for ITER. Several methods have been proposed, however, a measurement technique hasn't been established yet. A collective Thomson scattering (CTS) system based on a pulsed CO laser is being developed to demonstrate feasibility of alpha-particle diagnostics for ITER. The pulse laser (15J, 1
m, 0.6 m) and a wide band (~ 8GHz) heterodyne receiver with a quantum-well infrared photodetector (QWIP) have been developed and installed in the JT-60U tokamak. Stray light is reduced by a notch filter with hot CO gas. Heterodyne receiver is absolutely calibrated using large area blackbody radiation source. Scattered signal from JT-60U plasma has not detected because of electrical noise originated from discharge of the pulsed laser and stray signal caused by impurity of the spectrum of the pulsed laser.
Matsumura, Akira*; Yamamoto, Tetsuya*; Shibata, Yasushi*; Nakai, Kei*; Zhang, T.*; Akutsu, Hiroyoshi*; Matsushita, Akira*; Yasuda, Susumu*; Takano, Shingo*; Nose, Tadao*; et al.
Posuto Shikuensu Jidai Ni Okeru Noshuyo No Kenkyu To Chiryo, p.427 - 435, 2002/07
no abstracts in English
Sekimoto, Hiroshi*; Igashira, Masayuki*; Yano, Toyohiko*; Obara, Toru*; Osaki, Toshiro*
JAERI-Tech 2002-008, 58 Pages, 2002/03
no abstracts in English
Kinouchi, Nobuyuki; Oishi, Tetsuya; Noguchi, Hiroshi; Kato, Shohei; Ishizawa, Masato*
Radioisotopes, 50(9), p.403 - 407, 2001/09
no abstracts in English
laser in JT-60UKondoh, Takashi; Lee, S.; Hutchinson, D. P.*; Richards, R. K.*
Review of Scientific Instruments, 72(1), p.1143 - 1146, 2001/01
Times Cited Count：13 Percentile：59.42(Instruments & Instrumentation)no abstracts in English
laser systemKondoh, Takashi; Lee, S.; Miura, Yukitoshi
Purazuma, Kaku Yugo Gakkai-Shi, 76(9), p.883 - 887, 2000/09
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：39.66(Physics, Fluids & Plasmas)no abstracts in English
particles by quantum molecular dynamics plus statistical decay modelMeigo, Shinichiro; Chiba, Satoshi; Shin, Kazuo*
Journal of Nuclear Science and Technology, 36(3), p.250 - 255, 1999/03
Times Cited Count：1 Percentile：13.15(Nuclear Science & Technology)no abstracts in English
Ozeki, Takahisa; C.Z.Cheng*; Nagashima, Keisuke
JAERI-Research 95-065, 22 Pages, 1995/10
JAERI-Research-95-065.pdf:0.75MB
no abstracts in English
Yamagiwa, Mitsuru
Nuclear Fusion, 35(10), p.1225 - 1230, 1995/00
Times Cited Count：0 Percentile：0.02(Physics, Fluids & Plasmas)no abstracts in English
Ozeki, Takahisa; C.Z.Cheng*; Nagashima, Keisuke
Nuclear Fusion, 35(12), p.1553 - 1562, 1995/00
Times Cited Count：3 Percentile：20.43(Physics, Fluids & Plasmas)no abstracts in English
Yamagiwa, Mitsuru; Kimura, Haruyuki; Takizuka, Tomonori
Nuclear Fusion, 29(10), p.1799 - 1806, 1989/10
Times Cited Count：1 Percentile：4.12(Physics, Fluids & Plasmas)no abstracts in English
Yamagiwa, Mitsuru; Takizuka, Tomonori
JAERI-M 88-092, 20 Pages, 1988/05
no abstracts in English
