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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.
Nakajima, Motoki; Hirose, Takanori; Tanigawa, Hisashi; Enoeda, Mikio
Journal of Plasma and Fusion Research SERIES, Vol.11, p.69 - 72, 2015/03
Water-cooled blanket is an attractive concept for its compactness and its compatibility with the conventional technologies for PWR. For blanket application, the structural material is required to be as thin as possible for tritium breeding. On the other hand, it is also required the pressure tightness to withstand 15 MPa of internal pressure. Therefore it is necessary to understand the corrosion mechanism in high temperature pressurized water. The effects of water flow and DO in the test water on corrosion properties were investigated using rotating disk specimen in autoclave. In summary, the weight loss by flowing was occurred except for test with DO 8 ppm, and it was more pronounced at lower DO concentration. Since Fe
O
was observed on the specimen of small weight change, and the iron-poor layer thickness increased with decreasing the specimen weight, it seemed that the formation of Fe
O
was effective for the suppression of weight loss.
Kanai, Akihiko*; Kasada, Ryuta*; Nakajima, Motoki; Hirose, Takanori; Tanigawa, Hisashi; Enoeda, Mikio; Konishi, Satoshi*
Journal of Nuclear Materials, 455(1-3), p.431 - 435, 2014/12
Times Cited Count:2 Percentile:14.33(Materials Science, Multidisciplinary)Enoeda, Mikio; Tanigawa, Hisashi; Hirose, Takanori; Nakajima, Motoki; Sato, Satoshi; Ochiai, Kentaro; Konno, Chikara; Kawamura, Yoshinori; Hayashi, Takumi; Yamanishi, Toshihiko; et al.
Fusion Engineering and Design, 89(7-8), p.1131 - 1136, 2014/10
Times Cited Count:22 Percentile:81.32(Nuclear Science & Technology)The development of a Water Cooled Ceramic Breeder (WCCB) Test Blanket Module (TBM) is being performed as one of the most important steps toward DEMO blanket in Japan. Regarding the fabrication technology development using F82H, the fabrication of a real scale mockup of the back wall of TBM was completed. Also the assembling of the complete box structure of the TBM mockup and planning of the pressurization testing was studied. The development of advanced breeder and multiplier pebbles for higher chemical stability was performed for future DEMO blanket application. From the view point of TBM test result evaluation and DEMO blanket performance design, the development of the blanket tritium simulation technology, investigation of the TBM neutronics measurement technology and the evaluation of tritium production and recovery test using D-T neutron in the Fusion Neutronics Source (FNS) facility has been performed.
As
Taen, Toshihiro*; Yagyuda, Hidenori*; Nakajima, Yasuyuki*; Tamegai, Tsuyoshi*; Okayasu, Satoru; Kitamura, Hisashi*; Murakami, Takeshi*; Laviano, F.*; Ghigo, G.*
Physica C, 484, p.62 - 65, 2013/01
Times Cited Count:8 Percentile:34.34(Physics, Applied)We report effects of particle energy on physical properties of Co-doped BaFe
As
in the case of Xe and Au irradiations. The irradiation-induced suppression of 
is found to be related with several factors, such as defect structures and the thickness of the crystal. Heavy-ion irradiation induces enhancement of critical current density 
, and a weak dip in the hysteresis loop. The fish-tail effect is completely suppressed by a modest density of defects. The enhancement of 
is closely related to the defect structure. Namely, splayed structure in columnar defects, inevitably introduced at lower energies, results in a strong enhancement of 
by forced entanglement of vortices.
Tamegai, Tsuyoshi*; Taen, Toshihiro*; Yagyuda, Hidenori*; Tsuchiya, Yuji*; Mohan, S.*; Taniguchi, Tomotaka*; Nakajima, Yasuyuki*; Okayasu, Satoru; Sasase, Masato*; Kitamura, Hisashi*; et al.
Superconductor Science and Technology, 25(8), p.084008_1 - 084008_14, 2012/08
Times Cited Count:103 Percentile:93.99(Physics, Applied)Various kinds of energetic particles are irradiated into iron-based superconductors, and their effects on the critical current density 
and vortex dynamics have been systematically studied. It is found that 
is enhanced and vortex dynamics is strongly suppressed by energetic particles having a sufficient energy deposition rate, similar to the case of high temperature cuprate superconductors. The enhancement of 
, in general, persists up to much higher irradiation doses than in cuprates. However, details of the effect of irradiation depend on the kind of ion species and their energies. Even with the same ions and energies, the effect is not universal for different kinds of iron-based superconductors. The correlated nature of defects created by heavy-ion irradiation is confirmed by the angular dependence of irreversible magnetization.
Ichikawa, Shoichi; Abe, Kazuyuki; Haga, Hiroyuki; Kajima, Hisashi*; Sakurai, Satoshi*; Katsuyama, Kozo; Maeda, Koji; Nishinoiri, Kenji
JAEA-Technology 2011-032, 46 Pages, 2012/01
The assembly technique to the capsular irradiation rig newly developed was established. In the irradiation examination, the assembling disassembling and reassembling to PFB110 "B11(1), B11(2)" and PFB140 "B14" that built in Am-MOX fuel pin was achieved. The reassembly technique by recycling the irradiation material was established in the assembly of B11(2). This time, the assembly and disassembly of B11 (1) were reported. Moreover, the assembly of B14 which improved the assembly technology of B11 (1) was reported.
Tamegai, Tsuyoshi*; Taen, Toshihiro*; Yagyuda, Hidenori*; Nakajima, Yasuyuki*; Okayasu, Satoru; Sasase, Masato*; Kitamura, Hisashi*; Murakami, Takeshi*; Kambara, Tadashi*; Kanai, Yasuyuki*
Physica C, 471, p.777 - 780, 2011/00
Times Cited Count:6 Percentile:27.22(Physics, Applied)Magnetic relaxations in Ba(Fe
Co
)
As
before and after swift particle irradiations are measured. The normalized relaxation rate S shows a clear suppression in a pristine sample at low fields below the self-field. Heavy-ion irradiations suppress these anomalies considerably, although there still remain weak features depending on ion species and/or energies. In a proton irradiated sample, the low-field anomaly of S survives although it is smeared compared with that in a pristine sample. All these results indicate that the low-field anomaly of S is suppressed by defects, and correlated defects have stronger effects.
As
with columnar defects introduced by heavy-Ion irradiationNakajima, Yasuyuki*; Tsuchiya, Yuji*; Taen, Toshihiro*; Yagyuda, Hidenori*; Tamegai, Tsuyoshi*; Okayasu, Satoru; Sasase, Masato*; Kitamura, Hisashi*; Murakami, Takeshi*
Physica C, 470(20), p.1103 - 1105, 2010/11
Times Cited Count:4 Percentile:20.50(Physics, Applied)We report the formation of columnar defects in Co-doped BaFe
As
single crystals with different heavy ion irradiations. The formation of columnar defects by 200 MeV Au ion irradiation is confirmed by transmission electron microscopy and their density is about 40% of the irradiation dose. Magneto-optical imaging and bulk magnetization measurements reveal that the critical current density 
is enhanced in the 200 MeV Au and 800 MeV Xe ion irradiated samples while 
is unchanged in the 200 MeV Ni ion irradiated sample. We also find that vortex creep rates are strongly suppressed by the columnar defects. We compare the effect of heavy-ion irradiation into Co-doped BaFe
As
and cuprate superconductors.
Abe, Kazuyuki; Kobayashi, Takashi*; Kajima, Hisashi*; Yoshikawa, Katsunori; Nagamine, Tsuyoshi; Nakamura, Yasuo
JAEA-Technology 2008-008, 53 Pages, 2008/03
MARICO-2 is a Testing Rig for the continuous irradiation examination of ODS ferrite steel etc.. It was necessary to re-assemble of MARICO-2 in Fuel Monitoring Facility (FMF). However, MARICO-2 is not applicable a past technology of re-assembly because it is a Rig of the total length about 11 m and its hex-tube must be welded by remote control. Then, MARICO-2 re-assembly technology development was executed, the device was designed, it produced, and the procedure of re-assembly by remote control was established.
Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.
Nuclear Fusion, 44(2), p.329 - 334, 2004/02
no abstracts in English
Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.
Nuclear Fusion, 44(2), p.329 - 334, 2004/02
Times Cited Count:7 Percentile:22.12(Physics, Fluids & Plasmas)no abstracts in English
Saito, Shinzo; Tanaka, Toshiyuki; Sudo, Yukio; Baba, Osamu; ; Hishida, Makoto; ; ; Shinohara, Yoshikuni; ; et al.
Nihon Genshiryoku Gakkai-Shi, 32(9), p.847 - 871, 1990/09
no abstracts in English
Nakajima, Motoki; Hirose, Takanori; Tanigawa, Hisashi; Enoeda, Mikio
no journal, ,
no abstracts in English
Nakajima, Motoki; Hirose, Takanori; Tanigawa, Hisashi; Tanigawa, Hiroyasu; Enoeda, Mikio
no journal, ,
no abstracts in English
Tanigawa, Hisashi; Gwon, H.; Hirose, Takanori; Nakajima, Motoki; Kawamura, Yoshinori
no journal, ,
Blanket in fusion nuclear reactor has three functions such as neutron shielding, heat recovery and tritium breeding. Blankets with ceramic breeder materials has a box structure made of reduced activation ferritic/martensitic steel, and pebbles of breeder and neutron multiplier materials are packed into the box. Heat and neutron loads on the blanket are cooled by high temperature and pressure coolant such as water and helium. In this study, strength and pressure integrity are assessed for the water-cooled ceramic breeder blanket developed in JAEA. Existing design standards for pressure equipment are used in the analysis and their applicability to the fusion blanket is discussed.
Hirose, Takanori; Tanigawa, Hisashi; Nakajima, Motoki; Gwon, H.; Miyata, Satoru; Sato, Satoshi; Kawamura, Yoshinori; Yamanishi, Toshihiko
no journal, ,
no abstracts in English
Gwon, H.; Tanigawa, Hisashi; Nakajima, Motoki; Hirose, Takanori; Kawamura, Yoshinori
no journal, ,
It is expected that the neutron wall loading in DEMO is larger than that in ITER, over 0.78 MW/m
. It is concerned that the decay heat due to the large neutron wall loading will lead to excessive temperature rising in blanket. In present study, the thermal response characteristics of blanket caused by the decay heat under LOCA were evaluated. In addition we considered how to effectively mitigate the excessive temperature rising based on the evaluation results.
Abe, Kazuyuki; Kobayashi, Takashi*; Kajima, Hisashi*; Nagamine, Tsuyoshi; Nakamura, Yasuo
no journal, ,
To clarify behavior of the material and fuel of the fast reactor under high burn-up and the high fluence, re-assembly of "JOYO" irradiation rig is executed in Japan Atomic Energy Agency. This time, the re-assembling technology with a welding was established, newly. This technology is an upgrade of the continuance irradiation technology further for clear of the irradiation behavior of the fuel and the material.
Nakajima, Motoki; Kanai, Akihiko*; Hirose, Takanori; Tanigawa, Hisashi; Enoeda, Mikio
no journal, ,
no abstracts in English