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Ishikawa, Ryoya*; Suzuki, Masatoshi*; Kino, Yasushi*; Endo, Satoru*; Nakajima, Hiroo*; Oka, Toshitaka; Takahashi, Atsushi*; Shimizu, Yoshinaka*; Suzuki, Toshihiko*; Shinoda, Hisashi*; et al.
KEK Proceedings 2022-2, p.61 - 66, 2022/11
The balance between oxidative stress and antioxidant activity, which is a defense mechanism against oxidative stress, was investigated in the liver and bladder of wild Japanese macaques captured in Fukushima Prefecture. No significant induction of oxidative stress by exposure to environmental radionuclides after the Fukushima nuclear accident was observed, suggesting that the stress defense mechanism of the organism is activated in some organs.
Kusano, Kanya*; Ichimoto, Kiyoshi*; Ishii, Mamoru*; Miyoshi, Yoshizumi*; Yoden, Shigeo*; Akiyoshi, Hideharu*; Asai, Ayumi*; Ebihara, Yusuke*; Fujiwara, Hitoshi*; Goto, Tadanori*; et al.
Earth, Planets and Space (Internet), 73(1), p.159_1 - 159_29, 2021/12
Times Cited Count：6 Percentile：49.29(Geosciences, Multidisciplinary)The PSTEP is a nationwide research collaboration in Japan and was conducted from April 2015 to March 2020, supported by a Grant-in-Aid for Scientific Research on Innovative Areas from the Ministry of Education, Culture, Sports, Science and Technology of Japan. It has made a significant progress in space weather research and operational forecasts, publishing over 500 refereed journal papers and organizing four international symposiums, various workshops and seminars, and summer school for graduate students at Rikubetsu in 2017. This paper is a summary report of the PSTEP and describes the major research achievements it produced.
Te
/BiTe
down to 6 KFukasawa, Takuro*; Kusaka, Shotaro*; Sumida, Kazuki; Hashizume, Mizuki*; Ichinokura, Satoru*; Takeda, Yukiharu; Ideta, Shinichiro*; Tanaka, Kiyohisa*; Shimizu, Ryota*; Hitosugi, Taro*; et al.
Physical Review B, 103(20), p.205405_1 - 205405_6, 2021/05
Times Cited Count：9 Percentile：64.95(Materials Science, Multidisciplinary)Takeda, Tetsuaki*; Inagaki, Yoshiyuki; Aihara, Jun; Aoki, Takeshi; Fujiwara, Yusuke; Fukaya, Yuji; Goto, Minoru; Ho, H. Q.; Iigaki, Kazuhiko; Imai, Yoshiyuki; et al.
High Temperature Gas-Cooled Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.5, 464 Pages, 2021/02
As a general overview of the research and development of a High Temperature Gas-cooled Reactor (HTGR) in JAEA, this book describes the achievements by the High Temperature Engineering Test Reactor (HTTR) on the designs, key component technologies such as fuel, reactor internals, high temperature components, etc., and operational experience such as rise-to-power tests, high temperature operation at 950
C, safety demonstration tests, etc. In addition, based on the knowledge of the HTTR, the development of designs and component technologies such as high performance fuel, helium gas turbine and hydrogen production by IS process for commercial HTGRs are described. These results are very useful for the future development of HTGRs. This book is published as one of a series of technical books on fossil fuel and nuclear energy systems by the Power Energy Systems Division of the Japan Society of Mechanical Engineers.
Oka, Toshitaka; Takahashi, Atsushi*; Koarai, Kazuma; Mitsuyasu, Yusuke*; Kino, Yasushi*; Sekine, Tsutomu*; Shimizu, Yoshinaka*; Chiba, Mirei*; Suzuki, Toshihiko*; Osaka, Ken*; et al.
Radiation Measurements, 134, p.106315_1 - 106315_4, 2020/06
Times Cited Count：5 Percentile：52.81(Nuclear Science & Technology)The relationship between the CO
radical intensity and the absorbed dose (dose response curve) of tooth enamel of Japanese macaque was observed by electron spin resonance and the detection limit of our system was estimated to be 33.5 mGy, which is comparable to the detection limit for human molar teeth. Using the dose response curve, external exposure dose for seven wild Japanese macaques captured in Fukushima prefecture were examined. The results suggest that the external exposure dose for the wild Japanese macaques were ranged between 45 mGy to 300 mGy.
-ray spectroscopy of 
Mg via knockout reactions at intermediate energiesMomiyama, Satoru*; Doornenbal, P.*; Scheit, H.*; Takeuchi, Satoshi*; Niikura, Megumi*; Aoi, Nori*; Li, K.*; Matsushita, Masafumi*; Steppenbeck, D.*; Wang, H.*; et al.
Physical Review C, 96(3), p.034328_1 - 034328_8, 2017/09
Times Cited Count：6 Percentile：46.71(Physics, Nuclear)no abstracts in English
Tamamura, Shuji*; Endo, Ryo*; Shimizu, Satoru*; Iwatsuki, Teruki; Amano, Yuki; Omi, Yasushi*; Igarashi, Toshifumi*
Journal of MMIJ, 128(10,11), p.570 - 575, 2012/10
no abstracts in English
Fe
Mo
O
(0 
x 1)Yoshida, Koji*; Ikeuchi, Shinya*; Shimizu, Hajime*; Okayasu, Satoru; Suzuki, Takashi*
Journal of the Physical Society of Japan, 80(4), p.044716_1 - 044716_4, 2011/04
Times Cited Count：5 Percentile：38.84(Physics, Multidisciplinary)We studied systematic changes of the structural, electric, and magnetic properties in SrFeMoO with 0 x 1, which bridges between a half-metallic double perovskite SrFeMoO (x = 0) and an antiferromagnetic metal SrFeO
(= SrFeO: x = 1). The lattice volume at room temperature linearly decreases with x. The decline steeply enhances around x = 0.5, which is accompanied with a symmetry change from a tetragonal to a cubic crystal structure. In the same composition, we also found changes in the electronic ground state from a metal to an insulator and in the magnetic one from ferromagnetism to paramagnetism. These results indicate the strong correlation among the crystal structure, itinerant electrons and occurrence of ferromagnetic state in the double perovskite. In addition, the value of the critical composition could reflect peculiar physical changes with x.
Sasaki, Satoru; Suto, Toshiyuki; Harada, Akio; Kurihara, Ryoichi; Yamamoto, Kazuyoshi; Tsuchida, Noboru; Shimizu, Isamu; Nomura, Toshibumi
Genshiryoku eye, 57(1), p.66 - 75, 2011/01
no abstracts in English
Sakurai, Shinji; Kawashima, Hisato; Higashijima, Satoru; Shimizu, Katsuhiro; Masaki, Kei; Asakura, Nobuyuki; Shibama, Yusuke; Sakasai, Akira
Journal of Nuclear Materials, 390-391, p.891 - 894, 2009/06
Times Cited Count：1 Percentile：10.21(Materials Science, Multidisciplinary)The entire plasma facing components should be water-cooled in JT-60SA. A cassette module of divertor is introduced for remote maintenance. The divertor targets are mounted on the cassette. A brazed carbon fiber composite target is promising candidate for the divertor target. The latest results of mock-ups test clarified that thermal fatigue life cycles are more than 1000 cycles of 15 MW/m
10 sec. The divertor is designed to control divertor detachment for heat load reduction. The vertical targets and a "V-shaped corner" like as that in ITER are adopted to enhance detachment. Divertor heat load and pumping efficiency has been evaluated, using 2D plasma fluid (SOLDOR) and neutral Monte-Carlo (NEUT2D) code. The plasma detachment occurs near the outer-strike point within the "V-shaped corner", which results in low peak heat flux density 5.8 MW/m for the case with additional gas puff of 510
/s compared to 11.4 MW/m for the case without "V-shaped corner".
Nakano, Tomohide; Kubo, Hirotaka; Asakura, Nobuyuki; Shimizu, Katsuhiro; Kawashima, Hisato; Higashijima, Satoru
Journal of Nuclear Materials, 390-391, p.255 - 258, 2009/06
Times Cited Count：22 Percentile：80.29(Materials Science, Multidisciplinary)Therefore it is concluded that the dominant radiator, C
, is produced by ionization of C
and recombination of C
at similar rates around the X-point in the detached plasma, and that C is the second biggest radiator. Further the transport loss of C will be investigated by an impurity transport code (IMPMC), in addition to comparison of the radiation power and atomic processes.
Nakano, Tomohide; Kubo, Hirotaka; Asakura, Nobuyuki; Shimizu, Katsuhiro; Higashijima, Satoru
Proceedings of 22nd IAEA Fusion Energy Conference (FEC 2008) (CD-ROM), 8 Pages, 2008/10
It has been found that tungsten accumulation becomes more significant with increasing plasma rotation velocity against the plasma current direction, where negative radial electric field is formed. In a high density plasma at 62% of the Greenwald density, the tungsten accumulation levels decreased significantly, suggesting a shielding effect of the peripheral plasma. It has been found that 
is produced by the volume recombination of 
and the ionization of 
comparably. In contrast, the volume recombination of is not detected, and the ionization flux of is less than 1% of the generation flux. Thus, this result suggests that another loss mechanism of such as transport loss from the 
-point is significant.
in detached divertor plasmas of JT-60UNakano, Tomohide; Kubo, Hirotaka; Asakura, Nobuyuki; Shimizu, Katsuhiro; Konoshima, Shigeru; Fujimoto, Kayoko; Kawashima, Hisato; Higashijima, Satoru
Nuclear Fusion, 47(11), p.1458 - 1467, 2007/11
Times Cited Count：20 Percentile：57.53(Physics, Fluids & Plasmas)no abstracts in English
Oku, Takayuki; Yamada, Satoru; Shinohara, Takenao; Suzuki, Junichi; Mishima, Kenji*; Hirota, Katsuya*; Sato, Hiromi*; Shimizu, Hirohiko
Physica B; Condensed Matter, 397(1-2), p.188 - 191, 2007/07
Times Cited Count：5 Percentile：27.11(Physics, Condensed Matter)We have studied a neutron polarization method by means of a quadrupole magnet. By passing through the aperture of the quadrupole magnet (QM), positive and negative polarity neutrons are accelerated in opposite directions and spatially separated due to the magnetic field gradient. Then, by extracting one spin component, we can obtain a highly polarized neutron beam. Since polarized neutrons do not interact with any substances in this method, we can obtain the polarized neutron beam free from neutron attenuation. As a result of a cold neutron beam polarization experiment by using the QM, we obtained extremely high neutron polarization degree P0.999. In this paper, we show some experimental results of the neutron polarization experiment and discuss the application of the QM-based polarizing device to neutron scattering experiments.
Kubo, Hirotaka; Sasaki, Akira; Moribayashi, Kengo; Higashijima, Satoru; Takenaga, Hidenobu; Shimizu, Katsuhiro; Nakano, Tomohide; Whiteford, A.*; Sugie, Tatsuo
Journal of Nuclear Materials, 363-365, p.1441 - 1445, 2007/06
Times Cited Count：6 Percentile：42.37(Materials Science, Multidisciplinary)no abstracts in English
Oku, Takayuki; Iwase, Hiroki; Shinohara, Takenao; Yamada, Satoru; Hirota, Katsuya*; Koizumi, Satoshi; Suzuki, Junichi; Hashimoto, Takeji; Shimizu, Hirohiko
Journal of Applied Crystallography, 40(s1), p.s408 - s413, 2007/04
Times Cited Count：28 Percentile：89.64(Chemistry, Multidisciplinary)Measuring efficiency and/or angular resolution of small-angle neutron scattering experiments can be improved by focusing neutrons on a detector plane. Thus, a magnetic focusing lens (MNL) have been installed into the SANS instrument, SANS-J-II, of JRR-3 in AEA for the focusing-geometry SANS (FSANS) experiments. The MNL is an extended Halbach-type permanent sextupole magnet. The inner diameter and length of the MNL are 35 mm and 1200 mm, respectively. As the MNL functions as the focusing lens only for the polarized neutron with positive polarity, the incident neutron polarization is set positive by using the supermirror polarizer and the two-coil spin flipper. The intensity distribution of the neutrons focused by the MNL at the detector position was measured by using a high-resolution photomultiplier-based scintillation detector. In this paper, the neutron focusing property of the focusing setup is investigated, and the performance of the FSANS instrument is discussed.
Nakano, Tomohide; Kubo, Hirotaka; Asakura, Nobuyuki; Shimizu, Katsuhiro; Konoshima, Shigeru; Fujimoto, Kayoko; Kawashima, Hisato; Higashijima, Satoru
Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 8 Pages, 2007/03
Volume recombination of C and 
into C is observed for the first time in detached plasmas with MARFE. It is found that the recombination flux of C to C is comparable to the ionization flux of C to C, and that the recombination zone is above an X-point and beneath the ionization zone. This result suggests that this volume recombination predominantly produces C ions, which contribute 60-80 % to the total radiation power in the divertor plasma.
Asakura, Nobuyuki; Kawashima, Hisato; Shimizu, Katsuhiro; Sakurai, Shinji; Fujita, Takaaki; Takenaga, Hidenobu; Nakano, Tomohide; Kubo, Hirotaka; Higashijima, Satoru; Hayashi, Takao; et al.
Europhysics Conference Abstracts (CD-ROM), 31F, 4 Pages, 2007/00
Divertor design for the JT-60 SA has been progressing in order to handle large heat flux during full pulse duration of 100 s. Divertor should be suitable for single null plasma experiments with the full power injection of 41 MW. The simulation results using 2D fluid (plasma) and Monte-Carlo (neutral) code are summarized. Lower single-null divertor is designed for ITER-like plasma configuration in order to study physics concept of the ITER divertor: control of the plasma detachment. Simulation results for various divertor geometries showed that the vertical target with V-shaped corner can produce plasma detachment near the outer strike-point for medium edge plasma density. It was also demonstrated that the divertor plasma became attached to move the outer strike point above the V-corner, suggesting that recover from sever detachment can be achieved by changing the plasma location. USN divertor will be designed for high-
plasma experiments with the highest shaping plasma of S=6.
Ninomiya, Hiromasa; Akiba, Masato; Fujii, Tsuneyuki; Fujita, Takaaki; Fujiwara, Masami*; Hamamatsu, Kiyotaka; Hayashi, Nobuhiko; Hosogane, Nobuyuki; Ikeda, Yoshitaka; Inoue, Nobuyuki; et al.
Journal of the Korean Physical Society, 49, p.S428 - S432, 2006/12
To contribute DEMO and ITER, the design to modify the present JT-60U into superconducting coil machine, named National Centralized Tokamak (NCT), is being progressed under nationwide collaborations in Japan. Mission, design and strategy of this NCT program is summarized.
Oku, Takayuki; Yamada, Satoru; Sasao, Hajime*; Suzuki, Junichi; Shinohara, Takenao*; Hirota, Katsuya*; Ikeda, Kazuaki*; Tsuzaki, Tsuyoshi*; Kiyanagi, Yoshiaki*; Furusaka, Michihiro*; et al.
Physica B; Condensed Matter, 385-386(2), p.1225 - 1228, 2006/11
Times Cited Count：10 Percentile：44.41(Physics, Condensed Matter)We have developed a magnetic neutron lens based on an extended Halbach-type permanent sextupole magnet with magnet pieces of NEOMAX-44H, -35EH and high saturation magnetization material, permendule. The aperture size of the magnet is 35 mm in diameter and the magnet length is 2,400 mm. The magnet generates a sextupole magnetic field 
with a gradient coefficient 
=10,600 T/m
inside the aperture, where 
is a distance from the magnet center axis. To prevent neutrons from hitting and reflecting at the inner surface of the magnet, the surface is covered with cadmium (Cd) sheets and also Cd pinhole slits with size of 30 mm in diameter are positioned in series inside the magnet aperture, resulting in the effective diameter of 30 mm. The neutron focusing property of the magnet is investigated by using pulsed polarized neutrons. The obtained results are discussed with the precise simulation results. Its application to the focusing-geometry small-angle neutron scattering experiments is also discussed.
