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I/
I and 
C records in a modern coral from Rowley Shoals off northwestern Australia reflect the 20th-century human nuclear activities and ocean/atmosphere circulationsMitsuguchi, Takehiro; Okabe, Nobuaki*; Yokoyama, Yusuke*; Yoneda, Minoru*; Shibata, Yasuyuki*; Fujita, Natsuko; Watanabe, Takahiro; Kokubu, Yoko
Journal of Environmental Radioactivity, 235-236, p.106593_1 - 106593_10, 2021/09
Times Cited Count：5 Percentile：33.8(Environmental Sciences)For a contribution to developing the usage of iodine-129 (I) as a tracer of deep-seated fluid, I/I and C were measured for annual bands (AD 1931-1991) of a modern coral collected from Northwestern Australia; the measurements were performed using the JAEA-AMS-TONO-5MV for I/I and an AMS facility of the University of Tokyo for C. Results indicate that both I/I and C distinctly increase from 1950s. The C increase can be ascribed to atmospheric nuclear tests, while the I/I increase is due to nuclear-fuel reprocessing as well as atmospheric nuclear tests. These results are in good agreement with previous studies, indicating that the I/I measurement by JAEA-AMS-TONO-5MV has been further developed.
Mo/
Tc generator by (n,
) methodFujita, Yoshitaka; Seki, Misaki; Namekawa, Yoji*; Nishikata, Kaori; Kimura, Akihiro; Shibata, Akira; Sayato, Natsuki; Tsuchiya, Kunihiko; Sano, Tadafumi*; Fujihara, Yasuyuki*; et al.
KURNS Progress Report 2018, P. 155, 2019/08
no abstracts in English
pellets for Mo-99 productionFujita, Yoshitaka; Nishikata, Kaori; Namekawa, Yoji*; Kimura, Akihiro; Shibata, Akira; Sayato, Natsuki; Tsuchiya, Kunihiko; Sano, Tadafumi*; Fujihara, Yasuyuki*; Zhang, J.*
KURRI Progress Report 2017, P. 126, 2018/08
no abstracts in English
Shudo, Yasuyuki*; Izumi, Atsushi*; Hagita, Katsumi*; Yamada, Takeshi*; Shibata, Kaoru; Shibayama, Mitsuhiro*
Macromolecules, 51(16), p.6334 - 6343, 2018/08
Times Cited Count：11 Percentile：40.31(Polymer Science) pellets for Mo-99 production, 3Ishida, Takuya; Suzuki, Yoshitaka; Nishikata, Kaori; Yonekawa, Minoru; Kato, Yoshiaki; Shibata, Akira; Kimura, Akihiro; Matsui, Yoshinori; Tsuchiya, Kunihiko; Sano, Tadafumi*; et al.
KURRI Progress Report 2015, P. 64, 2016/08
no abstracts in English
Mo/
Tc production by neutron activation methodIshida, Takuya; Shiina, Takayuki*; Ota, Akio*; Kimura, Akihiro; Nishikata, Kaori; Shibata, Akira; Tanase, Masakazu*; Kobayashi, Masaaki*; Sano, Tadafumi*; Fujihara, Yasuyuki*; et al.
JAEA-Technology 2015-030, 42 Pages, 2015/11
JAEA-Technology-2015-030.pdf:4.82MB
The research and development (R&D) on the production of Mo/Tc by neutron activation method ((n, ) method) using JMTR has been carried out in the Neutron Irradiation and Testing Reactor Center. The specific radioactivity of Mo by (n, ) method is extremely low compared with that by fission method ((n,f) method), and as a result, the radioactive concentration of the obtained Tc solution is also lowered. To solve the problem, we propose the solvent extraction with methyl ethyl ketone (MEK) for recovery of Tc from Mo produced by (n, ) method. We have developed the Mo/Tc separation/extraction/concentration devices and have carried out the performance tests for recovery of Tc from Mo produced by (n, ) method. In this paper, in order to establish an experimental system for Mo/Tc production, the R&D results of the system are summarized on the improvement of the devices for high-recovery rate of Tc, on the dissolution of the pellets, which is the high-density molybdenum trioxide (MoO) pellets irradiated in Kyoto University Research Reactor (KUR), on the production of Tc, and on the inspection of the recovered Tc solutions.
Takeuchi, Tomoaki; Yamamoto, Keiichi; Otsuka, Noriaki; Shibata, Hiroshi; Shibata, Akira; Takemoto, Noriyuki; Tsuchiya, Kunihiko; Sano, Tadafumi*; Unesaki, Hironobu*; Fujihara, Yasuyuki*; et al.
KURRI Progress Report 2014, P. 108, 2015/07
Investigation of a relation between output power and brightness of Cherenkov light of a specific fuel element at KUR by a CCD camera was performed due to a development of a real-time in-core measurement technique using Cherenkov light. The results indicate that the inhomogeneous distribution of output power and the shadow of the control-rod guide tubes and the other irradiation equipment have significant effects on the brightness of the Cherenkov light. These effects could be suppressed by using a number of cameras located at various positions.
Otsuka, Noriaki; Takeuchi, Tomoaki; Yamamoto, Keiichi; Shibata, Akira; Kimura, Nobuaki; Takemoto, Noriyuki; Tanimoto, Masataka; Tsuchiya, Kunihiko; Sano, Tadafumi*; Unesaki, Hironobu*; et al.
KURRI Progress Report 2013, P. 215, 2014/10
Investigation of a relation between reactor power and brightness of Cherenkov light at Kyoto University Research reactor (KUR) by a CCD camera was performed due to a development of a real-time in-core measurement technique using Cherenkov light. Analyzing the brightness value of individual RGB color component at each pixel, some of the G and B brightness values reached the maximum value of 8-bit binary number, i.e. 255, above about 2-3 MW. Therefore, we corrected the G and B brightness values by the R signals whose brightness value did not saturate even at 5 MW, the maximum reactor power of KUR. Then, the total brightness value was in proportion to the reactor power after the correction. These results indicate the reactor power can be estimated by the observation of Cherenkov light.
Kimura, Nobuaki; Takeuchi, Tomoaki; Shibata, Akira; Takemoto, Noriyuki; Kimura, Akihiro; Naka, Michihiro; Nishikata, Kaori; Tanimoto, Masataka; Tsuchiya, Kunihiko; Sano, Tadafumi*; et al.
KURRI Progress Report 2012, P. 209, 2013/10
In research reactors, CCD cameras are used to observe reactor core for reactor operation management, e.g. to prevent debris from falling. In order to measure the reactor power and fuel burnup exactly by means of observation of Cherenkov light, the development of the on-line measurement device started in 2009. In this study, the wavelength and the absolute irradiance of the Cherenkov light were measured by a spectrometer, and the Cherenkov light was observed by the CCD camera. As a result, the measurement value is good agreement with the nominal value. On the other hand, the value by the visible imaging system was obtained the same tendency of nominal transmittance value of ND-filters.
Endo, Kiyoshi*; Shibata, Yasushi*; Yamamoto, Tetsuya*; Nakai, Kei*; Matsumura, Akira*; Sato, Takahiro; Yokoyama, Akihito; Koka, Masashi; Okubo, Takeru; Yamazaki, Akiyoshi; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 86, 2012/01
collisions at 
= 200 and 62.4 GeVAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06
Times Cited Count：184 Percentile：99.45(Physics, Nuclear)Transverse momentum distributions and yields for 
, and 
in collisions at = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different collisions. We also present the scaling properties such as 
and 
scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.
and Au+Au collisions at 
= 200 GeVAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.
Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04
Times Cited Count：9 Percentile：49.6(Physics, Nuclear)Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.
C values of organic matter in surface sediments off Saru River in northern Japan, one year after a flood event in 2006Nagao, Seiya*; Irino, Tomohisa*; Aramaki, Takafumi*; Ikehara, Ken*; Katayama, Hajime*; Otosaka, Shigeyoshi; Uchida, Masao*; Shibata, Yasuyuki*
Radiocarbon, 52(3), p.1068 - 1077, 2010/08
Times Cited Count：0 Percentile：0.01(Geochemistry & Geophysics)This study discusses the effects of flooding on the spatial distribution of organic matter on the shelf region of off the Saru River, southern part of Hokkaido, Japan, on the basis of the C and 
C values. Surface sediments on the shelf were collected in August 2007, one year after the severe flood in 2006. Suspended particles and sediment of the Saru River were also collected in August 2007 and 2008. The C values of organic matter in the shelf sediments ranged from -665 to -77 per mil. The silt and clay sediments had C values of -240 to -77 per mil, but the sandy sediments ranged from -665 to -388 per mil. The values of particulate organic carbon in the Saru River are -292 to -247 per mil at normal flow conditions. These results indicate that surface soil with relatively older organic matter is deposited on the shelf region by the flooding event, and freshly-produced organic matter in sea surface is deposited after the flooding.
Kumamoto, Yuichiro*; Aramaki, Takafumi*; Watanabe, Shuichi*; Yoneda, Minoru*; Shibata, Yasuyuki*; Togawa, Orihiko; Morita, Masatoshi*; Shitashima, Kiminori*
Journal of Oceanography, 64(3), p.429 - 441, 2008/06
Times Cited Count：11 Percentile：25.29(Oceanography)In 1995 and 2000, radiocarbon ratio (C) of total dissolved inorganic carbon was measured in the Japan Sea, a semi-closed marginal sea in the western North Pacific, where deep and bottom waters are formed in itself. Compiling them with historical radiocarbon data in the Japan Sea, temporal and spatial variations of the radiocarbon in the bottom water below 2000 m depth were elucidated. C in the bottom waters in the western Japan and Yamato Basins increased by about 20 ‰ between 1977/79 and 1995 and did not changed between 1995 and 1999/2000, suggesting penetration of surface bomb-produced radiocarbon into the bottom waters due to bottom ventilation in the earlier period and stagnation of the bottom ventilation in the following period, respectively. In the eastern Japan Basin, the bottom C increased by about 10 ‰ between 1977/79 and 2002, suggesting less ventilation of the bottom water in the basin. The temporal changes of the radiocarbon, tritium, and dissolved oxygen suggest sporadic occurrences of the bottom ventilation between 1979 and 1984 and its stagnation between 1984 and 2004 in the eastern Japan and Yamato Basins. The former is probably due to spreading of a newly ventilated bottom water in the western Japan Basin in the severe winter of 1976-1977 along the abyssal circulation in the Japan Sea. The latter does not conflict with temporal changes of bomb-produced 
Cs and chlorofluorocarbon-11 in the bottom water.
Muramatsu, Yasuyuki; Okawara, Masami; Suzuki, Toshiyuki; Shibata, Isao; Fuketa, Toyoshi
JAEA-Technology 2007-028, 47 Pages, 2007/03
JAEA-Technology-2007-028.pdf:4.76MB
As a part of Advanced LWR Fuel Performance and Safety Research Program, irradiation experiments are conducted with high burnup uranium dioxide fuel and uranium-plutonium mixed oxide (MOX) fuel in the Nuclear Safety Research Reactor. When an irradiation capsule is transferred and loaded to the reactor core, a capsule loader is used. The previous capsule loader, however, could not have enough shielding capability against neutron flux from high burnup MOX fuel. In order to fulfill the requirement and to handle a new high pressure water capsule, accordingly, a type-B capsule loader was developed.
Murao, Hiroyuki; Muramatsu, Yasuyuki; Okawara, Masami; Shibata, Isao
JAEA-Technology 2006-062, 32 Pages, 2007/02
JAEA-Technology-2006-062.pdf:1.81MB
In NSRR (Nuclear Safety Research Reactor) experiments, test fuels are inserted in the especial capsule and the capsule will be inserted into the experimental tube which is located in the center of reactor core. In NSRR, there are 17 types of atmospheric pressure capsule, and one of them Type X-IV atmospheric pressure capsule has been produced 6 times under authorization of Ministry of Education, Culture, Sports, Science and Technology (MEXT). Application for the 7th time of authorization was submitted to the MEXT in June 2006. On this application, standard which is used to design was changed to The Japan Society of Mechanical Engineers (JSME) S NC1-2005 from the Notification 501 of the Ministry of Economy, Trade and Industry (METI). The JSME S NC1-2005 introduced the service condition in addition to the reactor condition which has been used in the Notification 501. In this application, stress limits were calculated based on the service condition. The JSME S NC1-2005 requires estimation of combined stress for Class1 support structures, which was unnecessary in the Notification 501. In this application, combined stresses were calculated and confirmed not to exceed the stress limits.
Imai, Makoto*; Sataka, Masao; Kitazawa, Shinichi; Komaki, Kenichiro*; Kawatsura, Kiyoshi*; Shibata, Hiromi*; Tawara, Hiroyuki*; Azuma, Toshiyuki*; Kanai, Yasuyuki*; Yamazaki, Y.*
Nuclear Instruments and Methods in Physics Research B, 193(1-4), p.674 - 679, 2002/06
Times Cited Count：5 Percentile：34.51(Instruments & Instrumentation)no abstracts in English
Kitazawa, Shinichi; Sataka, Masao; Tawara, Hiroyuki*; Imai, Makoto*; Shibata, Hiromi*; Komaki, Kenichiro*; Azuma, Toshiyuki*; Kawatsura, Kiyoshi*; Kanai, Yasuyuki*
Atomic Collision Research in Japan, No.25, p.65 - 67, 1999/00
no abstracts in English
Kikuchi, Yasuyuki; Shibata, Keiichi; Asami, Tetsuo; ; *; *
Journal of Nuclear Science and Technology, 22(6), p.499 - 503, 1985/00
Times Cited Count：3 Percentile：53.49(Nuclear Science & Technology)no abstracts in English
Igarashi, Shinichi; Asami, Tetsuo; Kikuchi, Yasuyuki; Nakagawa, Tsuneo; Narita, Tsutomu; Shibata, Keiichi
Nihon Genshiryoku Gakkai-Shi, 26(3), p.191 - 198, 1984/00
Times Cited Count：3 Percentile：38.12(Nuclear Science & Technology)no abstracts in English
