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JAEA Reports

Development of dosimetry device in reactor cores under severe radiation environment (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; National Institute of Technology, Kisarazu College*

JAEA-Review 2021-043, 135 Pages, 2022/01

JAEA-Review-2021-043.pdf:5.39MB

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 "Development of dosimetry device in reactor cores under severe radiation environment" conducted from FY2018 to FY2020. Since the final year of this proposal was FY2020, the results for three fiscal years were summarized. Since the radiation level in the reactors and buildings of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (1F) is extremely high due to the accident, it is required to develop radiation measurement technology based on the needs at the 1F working site. In this study, we will develop technologies towards practical application of revolutionary radiation measurement system based on the dose measurement technology utilizing solar cell devices. It has been found

JAEA Reports

Development of dosimetry device in reactor cores under severe radiation environment (Contract research); FY2019 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; National Institute of Technology, Kisarazu College*

JAEA-Review 2020-051, 97 Pages, 2021/02

JAEA-Review-2020-051.pdf:5.02MB

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 "Development of Dosimeter for Severe Radiation Environment near Reactor Pressure Vessel" conducted in FY2019.

Journal Articles

Experimental validation of tensile properties measured with thick samples taken from MEGAPIE target

Saito, Shigeru; Suzuki, Kazuhiro; Hatakeyama, Yuichi; Suzuki, Miho; Dai, Y.*

Journal of Nuclear Materials, 534, p.152146_1 - 152146_16, 2020/06

 Times Cited Count:1 Percentile:23.17(Materials Science, Multidisciplinary)

A post-irradiation examination (PIE) was performed on the tensile specimens prepared from the MEGAPIE (MEGAwatt Pilot Experiment) target which were irradiated in flowing lead-bismuth eutectic (LBE). Thicknesses of the specimens were over two times larger than that of the standard specimen. The PIE revealed that the T91 specimens showed a 1.5-2.0 times larger total elongation (TE) compared to the literature values for a specimen with standard t/w (ratio of thickness to width). It could be suggested that the t/w and TE were strongly correlated. Then, we tried to investigate the effects of the t/w on the TE by comparing unirradiated specimens. We found that there was no t/w dependence on the strength and uniform elongation. On the other hand, the TE increases with increasing t/w. Based on the experimental data, we correlated the TE with various specimens t/w to estimate appropriate TE values, including that for the standard specimen.

JAEA Reports

Development of dosimeter for severe radiation environment near reactor pressure vessel (Contract research); FY2018 Center of World Intelligence Project for Nuclear Science/Technology and Human Resource Development

Collaborative Laboratories for Advanced Decommissioning Science; National Institute of Technology, Kisarazu College*

JAEA-Review 2019-033, 57 Pages, 2020/03

JAEA-Review-2019-033.pdf:3.17MB

JAEA/CLADS, had been conducting the Center of World Intelligence Project for Nuclear Science/Technology and Human Resource Development (hereafter referred to "the Project") in FY2018. The Project aims to contribute to solving problems in nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. 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. Among the adopted proposals in FY2018, this report summarizes the research results of the "Development of Dosimeter for Severe Radiation Environment near Reactor Pressure Vessel". Since the radiation level in the reactors and buildings of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (1F) is extremely high due to the accident, it is required to develop radiation measurement technology based on the needs at the 1F working site. In the previous studies, it has been verified that dosimeters using solar cell devices can be used for dose evaluation under high dose rate near the reactor pressure vessel because they have advantages such as unnecessity of a high-voltage source, ultra-compactness, lightweight, and high radiation resistance. Through this study, we will develop technologies towards practical application of revolutionary radiation measurement system based on the dose measurement technology utilizing solar cell devices.

Journal Articles

Diluted magnetic semiconductors with narrow band gaps

Gu, B.; Maekawa, Sadamichi

Physical Review B, 94(15), p.155202_1 - 155202_8, 2016/10

AA2016-0395.pdf:0.38MB

 Times Cited Count:17 Percentile:65.26(Materials Science, Multidisciplinary)

Journal Articles

Nuclear structure of elements with $$100 le Z le 109$$ from alpha spectroscopy

Asai, Masato; He${ss}$berger, F. P.*; Lopez-Martens, A.*

Nuclear Physics A, 944, p.308 - 332, 2015/12

 Times Cited Count:44 Percentile:94.97(Physics, Nuclear)

Nuclear structure of Z = 100-109 nuclei studied through $$alpha$$-decay spectroscopy have been reviewed. Experimental techniques and methods concerning separation techniques, summing effects in $$alpha$$ spectra, and the use of digital electronics for $$alpha$$-decay spectroscopy have been described in detail. The presentation of the experimental results and the physics discussion were focused on nuclear structure systematics in even-Z nuclei along the N = 151, 153, and 155 isotonic lines, where most progress has been achieved in the last 10 years.

Journal Articles

Effects of a low-energy proton irradiation on n$$^{+}$$/p-AlInGaP solar cells

Lee, H. S.*; Yamaguchi, Masafumi*; Ekins-Daukes, N. J.*; Khan, A.*; Takamoto, Tatsuya*; Imaizumi, Mitsuru*; Oshima, Takeshi; Ito, Hisayoshi

Physica B; Condensed Matter, 376-377, p.564 - 567, 2006/04

 Times Cited Count:2 Percentile:13.12(Physics, Condensed Matter)

no abstracts in English

Journal Articles

Nuclear analyses of some key aspects of the ITER design with Monte Carlo codes

Iida, Hiromasa; Petrizzi, L.*; Khripunov, V.*; Federici, G.*; Polunovskiy, E.*

Fusion Engineering and Design, 75(1-4), p.133 - 139, 2005/11

The design of the ITER machine was presented in 2001. A nuclear analysis has been performed on ITER by means of the most detailed models and the best assessed nuclear data and codes. As the construction phase of ITER is approaching, the design of the main components has been optimized/finalized and several minor design changes/optimizations have been made, which required refined calculations to confirm that nuclear design requirements are met. Some of the proposed design changes have been made to mitigate critical radiation shielding problems. This paper reviews some of the most recent neutronic work with emphasis on critical nuclear responses in the TF coil inboard legs and vacuum vessel related to design modifications made to the blanket modules and vacuum vessel.

Journal Articles

Theory of transport properties in the $$p$$-wave superconducting state of Sr$$_2$$RuO$$_4$$; A Microscopic determination of the gap structure

Nomura, Takuji

Journal of the Physical Society of Japan, 74(6), p.1818 - 1829, 2005/06

 Times Cited Count:25 Percentile:74.32(Physics, Multidisciplinary)

We provide a detailed quantitative analysis of transport properties in the $$p$$-wave superconducting state of Sr$$_2$$RuO$$_4$$. Specifically, we calculate ultrasound attenuation rate and electronic thermal conductivity within the mean field approximation. The momentum dependence of the gap function is determined by solving the Eliashberg equation for a three-band Hubbard model with the realistic electronic structure of Sr$$_2$$RuO$$_4$$. Consequently, we obtain the temperature dependence of the transport coefficients in agreement with the experimental results.

Journal Articles

Analysis of flight demonstration results of an InGaP/GaAs dual-junction tandem solar cell

Imaizumi, Mitsuru*; Sumita, Taishi*; Kawakita, Shiro*; Oshima, Takeshi; Ito, Hisayoshi; Kuwajima, Saburo*

Proceedings of 31st IEEE Photovoltaic Specialists Conference and Exhibition (PVSC-31), p.563 - 566, 2005/00

no abstracts in English

Journal Articles

Defect observation of AlInGaP irradiated with 30 keV protons for multi-junction space solar cells

Lee, H. S.*; Ekins-Daukes, N. J.*; Sasaki, Takuo*; Yamaguchi, Masafumi*; Khan, A.*; Takamoto, Tatsuya*; Agui, Takaaki*; Kamimura, Kunio*; Kaneiwa, Minoru*; Imaizumi, Mitsuru*; et al.

Proceedings of 31st IEEE Photovoltaic Specialists Conference and Exhibition (PVSC-31), p.556 - 558, 2005/00

no abstracts in English

Journal Articles

Native and radiation induced defects in lattice mismatched InGaAs and InGaP

Ekins-Daukes, N. J.*; Arafune, Koji*; Lee, H. S.*; Sasaki, Takuo*; Yamaguchi, Masafumi*; Khan, A.*; Takamoto, Tatsuya*; Agui, Takaaki*; Kamimura, Kunio*; Kaneiwa, Minoru*; et al.

Proceedings of 31st IEEE Photovoltaic Specialists Conference and Exhibition (PVSC-31), p.683 - 686, 2005/00

no abstracts in English

Journal Articles

Analysis on lift-off experiment in Halden reactor by FEMAXI-6 code

Suzuki, Motoe; Kusagaya, Kazuyuki*; Saito, Hiroaki*; Fuketa, Toyoshi

Journal of Nuclear Materials, 335(3), p.417 - 424, 2004/12

 Times Cited Count:5 Percentile:36.39(Materials Science, Multidisciplinary)

Experimental analysis was conducted on the Lift-Off experiment IFA-610.1 in Halden reactor by the FEMAXI-6 code using the detailed measured conditions of test-irradiation. Calculated fuel center temperatures on the two assumptions, i.e., (1) an enhanced thermal conductance across the pellet-clad bonding layer is maintained during the cladding creep-out by over-pressurization, and (2) the bonding layer is broken by the cladding creep-out, were compared with the measured data to analyze the effect of the creep-out by over-pressure inside the test pin. The measured center temperature rise was higher by a few tens of K than the prediction performed on the assumption (1), though this difference was much smaller than the predicted rise on the assumption (2). Therefore, it is appropriate to attribute the measured center temperature rise to the decrease of effective thermal conductance by irregular re-location of pellet fragments, etc. which was caused by cladding creep-out.

Journal Articles

Experience of HTTR construction and operation; Unexpected incidents

Fujimoto, Nozomu; Tachibana, Yukio; Saikusa, Akio*; Shinozaki, Masayuki; Isozaki, Minoru; Iyoku, Tatsuo

Nuclear Engineering and Design, 233(1-3), p.273 - 281, 2004/10

 Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)

From a viewpoint of heat leakage, there were two incidents during HTTR power-rise-tests. One was a temperature rise of the primary upper shielding, and the other was a temperature rise of the core support plate. Causes of the both incidents were small amount of helium flow in structures. For the temperature rise of the primary upper shielding, countermeasures to reduce the small amount of helium flow, enhancement of heat release and installation of thermal insulator were taken. For the temperature rise of the core support plate, temperature evaluations were carried out again considering the small amount of helium flow and design temperature of the core support plate was revised. By these countermeasures, the both temperatures were kept below their limits.

Journal Articles

Carrier removal and defect generation in lattice-mismatched InGaP under 1 MeV electron irradiation

Ekins-Daukes, N. J.*; Lee, H. S.*; Sasaki, Takuo*; Yamaguchi, Masafumi*; Khan, A.*; Takamoto, Tatsuya*; Agui, Takaaki*; Kamimura, Kunio*; Kaneiwa, Minoru*; Imaizumi, Mitsuru*; et al.

Proceedings of the 6th International Workshop on Radiation Effects on Semiconductor Devices for Space Application (RASEDA-6), p.87 - 91, 2004/10

no abstracts in English

Journal Articles

Carrier removal in lattice-mismatched InGaP solar cells under 1-MeV-electron irradiation

Ekins-Daukes, N. J.*; Lee, H. S.*; Sasaki, Takuo*; Yamaguchi, Masafumi*; Khan, A.*; Takamoto, Tatsuya*; Agui, Takaaki*; Kamimura, Kunio*; Kaneiwa, Minoru*; Imaizumi, Mitsuru*; et al.

Applied Physics Letters, 85(13), p.2511 - 2513, 2004/09

 Times Cited Count:11 Percentile:43.68(Physics, Applied)

no abstracts in English

Journal Articles

Study of radiation response on single-junction component sub-cells in triple-junction solar cells

Imaizumi, Mitsuru*; Takamoto, Tatsuya*; Sumita, Taishi*; Oshima, Takeshi; Yamaguchi, Masafumi*; Matsuda, Sumio*; Oi, Akihiko; Kamiya, Tomihiro

Proceedings of 3rd World Conference on Photovoltaic Energy Conversion (WCPEC-3) (CD-ROM), 4 Pages, 2004/01

The radiation response of InGaP, InGaAs and Ge single junction sub-cells in the triple junction space solar cell are studied in order to develop a device simulator which predicts the End-Of-Life performance of space solar cells. InGaP top-cells show no significant difference in radiation response between under AM0 light and dark conditions during irradiation. The radiation resistance of InGaAs cell which is used as middle cell decreases with increasing In contents. The Ge cell shows lower radiation reisitance as compared to InGaP and InGaAs cells.

Journal Articles

Main results of static and dynamic corrosion tests in oxygen-saturated liquid lead-bismuth

Kurata, Yuji; Kikuchi, Kenji; Saito, Shigeru; Futakawa, Masatoshi; Sasa, Toshinobu

FZKA-6876, p.190 - 198, 2003/12

A report at MEGAPIE(Megawatt Pilot Experiment) Technical R & D Meeting is collected into an FZK report. According to the static corrosion tests, Al surface-treated layer produced by the gas diffusion method exhabited corrosion resistance to liquid Pb-Bi, while Al surface-treated layer produced by the melt dipping method suffered a severe corrosion attack. Furtheremore, it was found that a thick ferrite layer was formed in the surface of austenitic stainless steel at 550$$^{circ}$$C. Dissolution at high temperature parts, precipitation of Fe-Cr alloy and deposition of PbO at low temperature parts occured in the first loop corrosion test. These caused plugging of the narrow passage in electro-magnetic pumu(EMP) system. Adoption of filters and a wide passage in an EMP system, and the use of an inner-polished tube specimen brought about a good effect.

Journal Articles

Triple ion beam irradiation tests on window materials of spallation targets

Futakawa, Masatoshi; Kurata, Yuji; Henry, J.*; Ioka, Ikuo; Saito, Shigeru; Naito, Akira

FZKA-6876, p.166 - 171, 2003/12

A report at MEGAPIE(Megawatt Pilot Experiment) Technical R & D Meeting is collected into an FZK report. Triple ion beam irradiation tests on T91 specimens were conducted under MEGAPIE condition using TIARA facility at JAERI. Results of triple ion beam irradiation up to 15dpa, 1400appm He, 10000appm H at 320$$^{circ}$$C were compared with those of single or dual beam irradiation of Fe or He ions by use of a micro-indentation method. Hardsness increase was mainly attributed to displacement damage by Fe ions. A little effect on hardness was found on simultaneous implantation of He and H ions. An analysis method to predict mechanical characterization form micro-indentation test results was developed on ion irradiated materials.

JAEA Reports

Effects of volume fraction and non-uniform arrangement of water moderator on reactivity

Cao, X.; Suzaki, Takenori; Kugo, Teruhiko; Mori, Takamasa

JAERI-Tech 2003-069, 36 Pages, 2003/08

JAERI-Tech-2003-069.pdf:3.77MB

From the viewpoint of nuclear criticality safety of fuel rod storage and transport, a series of critical experiments concerning effects of water hole size, water gap width, water-to-fuel volume ratio and non-uniform arrangement of water moderator have been performed at the Tank-type Critical Assembly (TCA) of Japan Atomic Energy Research Institute. In the present study, the effects of volume fraction and non-uniform arrangement of water moderator on reactivity are evaluated by the water level worth method and analyzed by the SRAC code. Error sources of experiments and calculations are discussed, especially for an energy group model. The calculation results of diffusion model with 17-group model show good agreement with the experiment results within a few dozen cents.

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