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Okuno, Yasuki*; Ishikawa, Norito; Akiyoshi, Masafumi*; Ando, Hirokazu*; Harumoto, Masaki*; Imaizumi, Mitsuru*
Japanese Journal of Applied Physics, 59(7), p.074001_1 - 074001_7, 2020/07
Times Cited Count:3 Percentile:15.66(Physics, Applied)Performance degradation prediction for space solar cells under irradiation with low-energy electrons is greatly affected by displacement threshold energy (Ed) when a displacement damage dose (DDD) model is used. According to recent studies, the Ed of P atoms is much lower than the conventional Ed value in InP-type solar cells irradiated with low-energy electrons. This indicates that the value of Ed typically used in DDD model leads to significant error in performance degradation prediction. In this study, degradation of AlInGaP solar cells is observed after irradiation with 60 keV electrons. The results suggest that the Ed of P atoms in AlInGaP solar cells is much smaller than the conventionally used Ed value. By using the DDD model with the Ed value obtained in this study, we demonstrated that the performance degradation predicted by the DDD model agrees well with the experimental results.
Itakura, Ryuji; Fushitani, Mizuho*; Hishikawa, Akiyoshi*; Sako, Tokuei*
AIP Conference Proceedings 1702, p.090021_1 - 090021_4, 2015/12
Times Cited Count:0 Percentile:0.00(Physics, Applied)We theoretically investigate coherent dynamics of ions created through ultrafast multichannel photoionization from a viewpoint of photoelectron-photoion correlation. The model calculation on single-photon ionization of Ar reveals that the coherent hole dynamics in Ar associated with a superposition of the spin-orbit states
(J = 3/2 and 1/2) can be identified by monitoring only the photoion created by a Fourier-transform limited extreme ultraviolet (EUV) pulse with the 9-fs pulse duration, while the coherence is lost by a chirped EUV pulse. It is demonstrated that by coincidence detection of the photoelectron and photoion the coherent hole dynamics can be extracted even in the case of ionization by a chirped EUV pulse with the sufficiently wide bandwidth.
Itakura, Ryuji; Fushitani, Mizuho*; Hishikawa, Akiyoshi*; Sako, Tokuei*
Journal of Physics B; Atomic, Molecular and Optical Physics, 47(19), p.195602_1 - 195602_9, 2014/10
Times Cited Count:3 Percentile:18.31(Optics)Ultrafast multichannel single-photon ionization of Ar is investigated theoretically by a model calculation incorporating correlation between the photoelectron and photoion. It is shown that the coherent hole dynamics in Ar associated with a superposition of the spin-orbit states can be observed by using a Fourier-transform limited laser pulse for ionization, while the coherence is degraded or lost by chirping a laser pulse. We demonstrate that the coherent hole dynamics can be retrieved even in the case of a chirped laser pulse, by labeling the photoion dynamics with the counterpart photoelectron energy.
Yabashi, Makina*; Tanaka, Hitoshi*; Tanaka, Takashi*; Tomizawa, Hiromitsu*; Togashi, Tadashi*; Nagasono, Mitsuru*; Ishikawa, Tetsuya*; Harries, J.; Hikosaka, Yasumasa*; Hishikawa, Akiyoshi*; et al.
Journal of Physics B; Atomic, Molecular and Optical Physics, 46(16), p.164001_1 - 164001_19, 2013/08
Times Cited Count:72 Percentile:94.78(Optics)Miura, Kenta*; Machida, Yuki*; Uehara, Masato*; Kiryu, Hiromu*; Ozawa, Yusuke*; Sasaki, Tomoyuki*; Hanaizumi, Osamu*; Sato, Takahiro; Ishii, Yasuyuki; Koka, Masashi; et al.
Key Engineering Materials, 497, p.147 - 150, 2012/00
Times Cited Count:7 Percentile:94.55(Engineering, Electrical & Electronic)Miura, Kenta*; Machida, Yuki*; Uehara, Masato*; Kiryu, Hiromu*; Ozawa, Yusuke*; Sasaki, Tomoyuki*; Hanaizumi, Osamu*; Sato, Takahiro; Ishii, Yasuyuki; Koka, Masashi; et al.
Key Engineering Materials, 497, p.147 - 150, 2011/12
Times Cited Count:6 Percentile:2.48Sakuraba, Naotoshi; Numata, Masami; Komiya, Tomokazu; Ichise, Kenichi; Nishi, Masahiro; Tomita, Takeshi; Usami, Koji; Endo, Shinya; Miyata, Seiichi; Kurosawa, Tatsuya; et al.
JAEA-Technology 2009-071, 34 Pages, 2010/03
As a part of maintenance technology of a large-sized glove box for handling of TRU nuclides, we developed replacement technology for front acrylic panels using the bag-in/bag-out method and applied this technology to replace the deteriorated front acrylic panels at Waste Safety Testing Facility (WASTEF) in Nuclear Science Research Institute of Japan Atomic Energy Agency (JAEA). As a consequence, we could safely replace the front acrylic panels under the condition of continuous negative pressure only with partial decontamination of the glove box. We also demonstrated that the present technology is highly effective in points of safety, workability and cost as compared to the usual replacement technology for front acrylic panels of a glove box, where workers in an air-line suit replace directly the front acrylic panels in a green house.
Saito, Shigeru; Kikuchi, Kenji*; Hamaguchi, Dai; Usami, Koji; Ishikawa, Akiyoshi; Nishino, Yasuharu; Endo, Shinya; Kawai, Masayoshi*; Dai, Y.*
Journal of Nuclear Materials, 398(1-3), p.49 - 58, 2010/03
Times Cited Count:6 Percentile:39.41(Materials Science, Multidisciplinary)In several institutes, R&D for an ADS have been progressed. Ferritic / martensitic (F/M) steels are the candidate material for the beam window. To obtain the irradiation data, the PIE work of the SINQ target irradiation program (STIP) specimens was carried out at JAEA. In this study, the results of PIE on F/M steel F82H and its welded joint will be reported. The results of tensile tests indicate that the irradiation hardening occurred with increasing dpa up to 10.1 dpa below 320C irradiation. At higher dose (- 11.8 dpa) and higher temperature (- 380
C), irradiation hardening and degradation of ductility relaxed. In this study, all specimens kept its ductility after irradiation and fractured in ductile manner. The fatigue life of F82H base metal is almost the same as that of unirradiated specimens. Though the number of specimen is limited, the fatigue life of F82H EB welded joints seems to increase after irradiation. The fracture surfaces of the specimens showed transgranular morphology. While F82H TIG welded specimens were not fractured by 10
cycles.
Motooka, Takafumi; Ishikawa, Akiyoshi; Numata, Masami; Endo, Shinya; Itonaga, Fumio; Kiuchi, Kiyoshi; Kizaki, Minoru
JAEA-Research 2007-031, 20 Pages, 2007/03
An effect of neptunium ions on corrosion of stainless steel in nitric acid solution was investigated by corrosion tests. Type SUS304L stainless steel was used for the tests. The corrosion tests were conducted in 9kmol/m nitric acid solutions containing neptunium ions, where test specimens were immersed or heat-transferred. As a result, we found that neptunium ions promote corrosion of stainless steels in nitric acid solution. This finding would contribute to modifications of the materials for spent fuel reprocessing process.
Saito, Shigeru; Kikuchi, Kenji; Usami, Koji; Ishikawa, Akiyoshi; Nishino, Yasuharu; Kawai, Masayoshi*; Dai, Y.*
Journal of Nuclear Materials, 343(1-3), p.253 - 261, 2005/08
Times Cited Count:9 Percentile:52.21(Materials Science, Multidisciplinary)A beam window of a spallation target will be subjected to proton/neutron irradiation, pressure wave and thermal stresses accompanied by high-energy proton beam injection. To obtain the irradiation data, the SINQ target irradiation program (STIP) was initiated in 1996 at Paul Scherrer Institute (PSI) and has been progressing. JAERI takes part in STIP and shares the PIE work. In this study, the results of tensile tests on austenitic stainless steels, JPCA and 316F SS, will be reported. The results indicate that the irradiation causes considerable hardening and degradation of ductility. The YS increases in this study are slightly large in comparison with those irradiated at fission reactor. Strain-to-necking (STN) values show sufficient large ductility of the irradiated JPCA-SA and 316F-SA. The trends of the STN decrease in this study are slightly abrupt in comparison with those irradiated at fission reactor. All specimens, including irradiated at embrittlement temperature for austenitic steels, fractured in ductile manner.
Saito, Shigeru; Kikuchi, Kenji; Usami, Koji; Ishikawa, Akiyoshi; Nishino, Yasuharu; Kawai, Masayoshi*; Dai, Y.*
Journal of Nuclear Materials, 329-333(Part1), p.1093 - 1097, 2004/08
Times Cited Count:6 Percentile:39.99(Materials Science, Multidisciplinary)In several institutes, research and development for an accelerator-driven spallation neutron source have been progressed. A beam window of a target will be subjected to proton/neutron irradiation, pressure wave and thermal stresses accompanied by high-energy proton beam injection. To obtain the irradiation data, the SINQ target irradiation program (STIP) at Paul Scherrer Institute (PSI) has been progressing. JAERI takes part in STIP and shares the PIE work. The STIP specimens are very small so that we developed a new fatigue-testing machine with ceramic piezoelectric actuator. The results showed that the numbers of cycles to failure (Nf) on the irradiated specimens were less than that of unirradiated specimens. Dpa dependence of Nf was not clearly seen in the irradiation conditions. On the other hand, fracture surface varied with irradiation conditions. Specimens irradiated at low temperature fractured in ductile manner. However, interglanular fractured surface was observed for 316F SS irradiated up to 12.5 dpa at 360C.
Sawa, Kazuhiro; Tobita, Tsutomu*; Takahashi, Masashi; Saito, Takashi; Iimura, Katsumichi; Yokouchi, Iichiro; Serizawa, Hiroyuki; Sekino, Hajime; Ishikawa, Akiyoshi
JAERI-Research 2001-043, 52 Pages, 2001/09
no abstracts in English
Minato, Kazuo; Sawa, Kazuhiro; Koya, Toshio; Tomita, Takeshi; Ishikawa, Akiyoshi; Baldwin, C. A.*; Gabbard, W. A.*; Malone, C. M.*
Nuclear Technology, 131(1), p.36 - 47, 2000/07
Times Cited Count:58 Percentile:94.71(Nuclear Science & Technology)no abstracts in English
Minato, Kazuo; Ogawa, Toru; Sawa, Kazuhiro; Ishikawa, Akiyoshi; Tomita, Takeshi; Iida, Shozo; Sekino, Hajime
Nuclear Technology, 130(3), p.272 - 281, 2000/06
Times Cited Count:73 Percentile:96.57(Nuclear Science & Technology)no abstracts in English
Minato, Kazuo; Ogawa, Toru; Sawa, Kazuhiro; Sekino, Hajime; Koya, Toshio; Kitagawa, Isamu; Ishikawa, Akiyoshi; Tomita, Takeshi;
Proc. of the Int. Conf. on Future Nuclear Systems (GLOBAL'99)(CD-ROM), 8 Pages, 1999/00
no abstracts in English
Ogawa, Toru; ; Ito, Akinori; ; Sekino, Hajime; Nishi, Masahiro; Ishikawa, Akiyoshi; Akabori, Mitsuo
Journal of Alloys and Compounds, 271-273, p.670 - 675, 1998/00
Times Cited Count:9 Percentile:52.14(Chemistry, Physical)no abstracts in English
Minato, Kazuo; Fukuda, Kosaku; Sekino, Hajime; Ishikawa, Akiyoshi;
Journal of Nuclear Materials, 252, p.13 - 21, 1998/00
no abstracts in English
Minato, Kazuo; Fukuda, Kosaku; Ishikawa, Akiyoshi; Mita, Naoaki
Journal of Nuclear Materials, 246(2-3), p.215 - 222, 1997/00
Times Cited Count:16 Percentile:75.29(Materials Science, Multidisciplinary)no abstracts in English
Tsukada, Takashi; Shiba, Kiyoyuki; Nakajima, Hajime; ; Kitagawa, Isamu; ; Sekino, Hajime; ; Itonaga, Fumio; Ishikawa, Akiyoshi
JAERI-M 92-169, 26 Pages, 1992/11
no abstracts in English
Shiba, Kiyoyuki; Tsukada, Takashi; Nakajima, Hajime; ; Kitagawa, Isamu; ; Sekino, Hajime; ; ; Itonaga, Fumio; et al.
JAERI-M 92-166, 27 Pages, 1992/11
no abstracts in English