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Collaborative Laboratories for Advanced Decommissioning Science; i-lab*
JAEA-Review 2022-042, 67 Pages, 2023/01
JAEA-Review-2022-042.pdf:7.42MB
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, 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 FY2020, this report summarizes the research results of the "Challenge to advancement of debris composition and direct isotope measurement by microwave-enhanced LIBS" conducted in FY2021. The present study aims to increase the emission intensity of LIBS (laser-induced breakdown spectroscopy) by superimposing MW (microwave) and apply it to uranium isotope measurement. In FY2021, after confirming that there was no problem in terms of specifications including noise leakage by downsizing the semiconductor MW oscillator and evaluating it as a single unit, the possibility of uranium isotope measurement was examined by applying it to the LIBS experiment. In addition, the optimized design of the MW antenna was carried out. By applying them, we confirmed the actual performance, …
Collaborative Laboratories for Advanced Decommissioning Science; i-lab*
JAEA-Review 2021-027, 62 Pages, 2021/11
JAEA-Review-2021-027.pdf:3.06MB
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 FY2020, this report summarizes the research results of the "Challenge to advancement of debris composition and direct isotope measurement by microwave-enhanced LIBS" conducted in FY2020. Although LIBS (laser-induced breakdown spectroscopy) is commercially available for application to remote composition measurement, it is not suitable for high radiation environment due to loss in optical fibers derived from the influence of radiation, reduction in laser transmission output, and nuclear fuel debris properties. There are general concerns of the signal strength decrease. In addition, since LIBS is generally considered to be unsuitable for isotope measurement, there are problems to be improved.
Mironov, M. I.*; Khudoleev, A. V.*; Kusama, Yoshinori
Plasma Physics Reports, 30(2), p.164 - 168, 2004/02
Times Cited Count：0 Percentile：0.02(Physics, Fluids & Plasmas)High-energy charge-exchange diagnostics can determine the distribution function of fast atoms produced via the neutralization of hydrogen ions by hydrogen-like impurity ions. Deriving the distribution function requires to know the composition and spatial distribution of the target ions in a plasma. A charge-exchange target forms as a result of the interaction between impurity nuclei and beam atoms. Depending on the arrangement of heating beams with respect to the diagnostics, it is necessary to calculate their trajectories. A model which takes into account elementary processes resulting in the ionization equilibrium of the ions of impurities in a specific tokamak configuration is proposed. The model is applied to the JT-60U plasma. Mechanisms for the formation of charge-exchange atomic flows are considered. The relative contributions of different heating injectors to the charge-exchange flow are estimated. Based on the calculated results, a method is proposed for local measurements of the ion distribution function with a stationary analyzer.
Katayama, Atsushi; Furukawa, Katsutoshi; Watanabe, Kazuo
Bunseki Kagaku, 52(6), p.461 - 467, 2003/06
Times Cited Count：0 Percentile：0.01(Chemistry, Analytical)An imaging ion detection system was introduced to a time-of-flight mass spectrometer (TOFMS) in order to increase dynamic range in the isotope ratio measurements. The new detection system utilizes a position sensitive micro channel plate (MCP) with a phosphor plate and a CCD camera which records light spots on the MCP. Mass discriminated ion beams produced by laser resonance ionization were swept on the surface of MCP by a time-depended electric field located in front of the MCP. The resulting light spots were recorded as images by CCD camera. A mass spectrum was obtained from the images. The present method was applied to the isotope analysis of calcium. A dynamic range of more than 5 orders of magnitude was achieved.
Nuclear Technology and Education Center
JAERI-Review 2003-003, 81 Pages, 2003/05
JAERI-Review-2003-003.pdf:3.48MB
This report summarizes the educational activities and related management of the Nuclear Technology andEducation Center (NuTEC) during the 2001 fiscal year. Both Tokyo and Tokai Education Centers have successfully conducted almost all the planned domestic and international training courses. In addition Tokai Education Center has performed the 3nd nuclear supervisor training course and introduced a new course for special nuclear emergency preparedness in response to the legal amendment after the criticality accident. The sum total number of participants was 1,310. The International Technology Transfer Division has not only planned and organized the international training courses, but also taken charge of the 3nd workshop on Human Resource Development in Nuclear Field in Asian and Pasific Region. Various researches have been made to improve the educational program.
