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Zn
Y
alloy using X-ray photoelectron spectroscopyMiyazaki, Hidetoshi*; Akatsuka, Tatsuyoshi*; Kimura, Koji*; Egusa, Daisuke*; Sato, Yohei*; Itakura, Mitsuhiro; Takagi, Yasumasa*; Yasui, Akira*; Ozawa, Kenichi*; Mase, Kazuhiko*; et al.
Materials Transactions, 64(6), p.1194 - 1198, 2023/06
Times Cited Count：1 Percentile：11.66(Materials Science, Multidisciplinary)We investigated the electronic structure of the MgZnY alloy using hard and soft X-ray photoemission spectroscopy and electronic band structure calculations to understand the mechanism of the phase stability of this material. Electronic structure of the MgZnY alloy showed a semi-metallic electronic structure with a pseudo-gap at the Fermi level. The observed electronic structure of the MgZnY alloy suggests that the presence of a pseudogap structure is responsible for phase stability.
Miura, Daisuke*; Sekine, Yurina; Nankawa, Takuya; Sugita, Tsuyoshi; Oba, Yojiro; Hiroi, Kosuke; Ozawa, Tatsuhiko
Carbohydrate Polymer Technologies and Applications (Internet), 4, p.100251_1 - 100251_9, 2022/12
The reaction mechanism of carboxymethyl cellulose nanofiber (CMCF) hydrogel formed by freeze-crosslinking was investigated. We succeeded in observing the hierarchical structural changes during the freeze-crosslinking reaction. Freeze-crosslinked CMCF hydrogels exhibited a characteristic hierarchical alignment structure from the angstrom to micrometer scale that differed from normal cross-linked CMCF hydrogels produced by a conventional method without freezing. It was shown that the characteristic hierarchical structure contributes the excellent mechanical properties of freeze-crosslinked CMCF hydrogels.
Miura, Kenta*; Sato, Takahiro; Ishii, Yasuyuki; Koka, Masashi; Kiryu, Hiromu*; Ozawa, Yusuke*; Takano, Katsuyoshi*; Okubo, Takeru; Yamazaki, Akiyoshi; Kada, Wataru; et al.
JAEA-Review 2012-046, JAEA Takasaki Annual Report 2011, P. 126, 2013/01
Miura, Kenta*; Sato, Takahiro; Ishii, Yasuyuki; Kiryu, Hiromu*; Ozawa, Yusuke*; Koka, Masashi; Takano, Katsuyoshi*; Okubo, Takeru; Yamazaki, Akiyoshi; Kada, Wataru; et al.
Key Engineering Materials, 534, p.158 - 161, 2013/00
Times Cited Count：5 Percentile：88.35(Nanoscience & Nanotechnology)
m band using focused proton beamMiura, 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：94.26(Engineering, Electrical & Electronic)Nishitani, Takeo; Yamanishi, Toshihiko; Tanigawa, Hiroyasu; Nozawa, Takashi; Nakamichi, Masaru; Hoshino, Tsuyoshi; Koyama, Akira*; Kimura, Akihiko*; Hinoki, Tatsuya*; Shikama, Tatsuo*
Fusion Engineering and Design, 86(12), p.2924 - 2927, 2011/12
Times Cited Count：7 Percentile：46.65(Nuclear Science & Technology)Several technical R&D activities related to the blanket materials are newly launched as a part of the Broader Approach (BA) activities, which was initiated by the EU and Japan. According to the common interests of these parties for DEMO, R&Ds on reduced activation ferritic/martensitic (RAFM) steels as structural material, SiCf/SiC composites as a flow channel insert material and/or alternative structural material, advanced tritium breeders and neutron multipliers, and tritium technology are carried out through the BA DEMO R&D program, in order to establish the technical bases on the blanket materials and the tritium technology required for DEMO design. This paper describes overall schedule of those R&D activities and recent progress in Japan carried out by JAEA as the domestic implementing agency on BA, collaborating with Japanese universities and other research institutes.
m band using focused proton beamMiura, 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：2.48Koyama, Shinichi; Yamagishi, Isao; Suzuki, Tatsuya*; Ozawa, Masaki*; Fujita, Reiko*; Okada, Ken*; Tatenuma, Katsuyoshi*; Mimura, Hitoshi*; Fujii, Yasuhiko
Proceedings of International Conference on Toward and Over the Fukushima Daiichi Accident (GLOBAL 2011) (CD-ROM), 8 Pages, 2011/12
Effective separation of MA and LLFP, transmutation and utilization were the main directions of Advanced OREINT Cycle project. Study for each integrant technology was concluded as first trial of the project. TPR enabled to separate MA/Ln and then Am/Cm precisely from spent fuel in HCl and HNO
media. CEE method could separate the light PGM and Tc by HCl media. Recovery of Cs from simulated HLLW coul be achieved more than 90 %. In addition, the perspective for next phase was proposed.
Nishitani, Takeo; Tanigawa, Hiroyasu; Nozawa, Takashi; Jitsukawa, Shiro; Nakamichi, Masaru; Hoshino, Tsuyoshi; Yamanishi, Toshihiko; Baluc, N.*; M
slang, A.*; Lindou, R.*; et al.
Journal of Nuclear Materials, 417(1-3), p.1331 - 1335, 2011/10
Times Cited Count：14 Percentile：69.66(Materials Science, Multidisciplinary)As a part of the Broader Approach (BA) activities, the research and development on blanket related materials and tritium technology have been initiated toward DEMO by Japan and EU. Recently, those five R&D items have progressed substantially in Japan and EU. As a preparatory work aiming at the RAFM steel muss-production development, a 5-ton heat of RAFM steel (F82H) was procured with the Electro Slag Re-melting as a secondary melting. The result of the double notch tensile test method for the NITE-SiC
/SiC specimen indicated notch insensitivity and very minor size effect on proportional limit tensile stress and fracture strength. For the fabrication technology development of beryllide neutron multiplayer pebbles, Be- Ti inter-metallic pebbles have been sintered directly from the mixed powder of Be and Ti in Japan.
Koyama, Shinichi; Ozawa, Masaki; Kurosawa, Kiyoko*; Tatenuma, Katsuyoshi*; Sato, Yoshihiko*; Okada, Ken*
Journal of Radioanalytical and Nuclear Chemistry, 286(3), p.807 - 813, 2010/12
Times Cited Count：1 Percentile：9.57(Chemistry, Analytical)A multi-functional separation process is proposed on the Adv.-ORIENT cycle concept. In this process, hydrochloric acid, mixture of nitric acid and methanol should be used as eluents. Two important subjects should be solved so as to prove the availability. One is corrosion aspect for the use of HCl solution, Tantalum was anti-corrosive in HCl media, and Hastelloy-B seemed to be acceptable at RT, with evidence of low corrosion rate (
0.1 mm/y). The other is explication of the reactive safety between ion exchange resin and solvent (nitric acid and methanol). The reaction occurred regardless of nitric acid concentration and presence or absence of methanol when the temperature of heater reached 220 
C. However, it was confirmed that the reaction did not occur when the heating temperature decreased.
Yonekawa, Minoru; Sozawa, Shizuo; Kato, Yoshiaki; Shibata, Akira; Nakagawa, Tetsuya; Kusunoki, Tsuyoshi
JAEA-Review 2010-049, 18 Pages, 2010/11
JAEA-Review-2010-049.pdf:2.09MB
The hot laboratory (JMTR-HL) was founded to examine the objects mainly irradiated in the JMTR (Japan Materials Testing Reactor), and has been operated since 1971. The JMTR has been stopped from FY2006 for the refurbishment and will be re-started from FY2011. The post irradiation examination for high burn up fuels and large specimen will be carried out in the restarted JMTR. The JMTR-HL plans to put a three dimensional X-ray Computerized Tomography (CT) inspection system in place until the restart of JMTR in order to satisfy the requirement of valuable irradiation data for safety and plant life time management of nuclear power plants in the future. The three dimensional X-ray CT inspection system is able to observe a defect geometry closely and visually compared with a two dimensional system. In this paper, system design, production, installation and performance tests of an X-ray CT inspection system in a hot cell are reported. The X-ray CT inspection system consists of a computed tomography scanner, an X-ray source, a movable sample positioned, an X-ray detector, a collimator, and so on. After installation of apparatus, performance tests using irradiated fuel rods and radioisotopes were carried out to confirm the influence of 
rays and transmission X-ray property. By this development of the X-ray CT inspection system, it became possible to provide data with high technical value for post irradiation examination of high burn-up fuels and large type specimens.
Tobita, Kenji; Nishio, Satoshi*; Enoeda, Mikio; Nakamura, Hirofumi; Hayashi, Takumi; Asakura, Nobuyuki; Uto, Hiroyasu; Tanigawa, Hiroyasu; Nishitani, Takeo; Isono, Takaaki; et al.
JAEA-Research 2010-019, 194 Pages, 2010/08
JAEA-Research-2010-019-01.pdf:48.47MBJAEA-Research-2010-019-02.pdf:19.4MB
This report describes the results of the conceptual design study of the SlimCS fusion DEMO reactor aiming at demonstrating fusion power production in a plant scale and allowing to assess the economic prospects of a fusion power plant. The design study has focused on a compact and low aspect ratio tokamak reactor concept with a reduced-sized central solenoid, which is novel compared with previous tokamak reactor concept such as SSTR (Steady State Tokamak Reactor). The reactor has the main parameters of a major radius of 5.5 m, aspect ratio of 2.6, elongation of 2.0, normalized beta of 4.3, fusion out put of 2.95 GW and average neutron wall load of 3 MW/m
. This report covers various aspects of design study including systemic design, physics design, torus configuration, blanket, superconducting magnet, maintenance and building, which were carried out increase the engineering feasibility of the concept.
Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05
Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.
Araki, Masanori; Hayashi, Kimio; Tobita, Kenji; Nishitani, Takeo; Tanigawa, Hiroyasu; Nozawa, Takashi; Yamanishi, Toshihiko; Nakamichi, Masaru; Hoshino, Tsuyoshi; Ozeki, Takahisa; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 86(4), p.231 - 239, 2010/04
The Broader Approach Activities, which support the ITER Project and implement activities to aim early realization of fusion energy, is an EU-Japan collaborative project to carry out various kinds of researches and developments during the period of the ITER construction phase. In this special topic, achievements and prospects of the projects on the International Fusion Energy Research Centre (IFERC) is described.
Matsui, Yoshinori; Takahashi, Hiroyuki; Yamamoto, Masaya; Nakata, Masahito; Yoshitake, Tsunemitsu; Abe, Kazuyuki; Yoshikawa, Katsunori; Iwamatsu, Shigemi; Ishikawa, Kazuyoshi; Kikuchi, Taiji; et al.
JAEA-Technology 2009-072, 144 Pages, 2010/03
JAEA-Technology-2009-072.pdf:45.01MB
"R&D Project on Irradiation Damage Management Technology for Structural Materials of Long-life Nuclear Plant" was carried out from FY2006 in a fund of a trust enterprise of the Ministry of Education, Culture, Sports, Science and Technology. The coupled irradiations or single irradiation by JOYO fast reactor and JRR-3 thermal reactor were performed for about two years. The irradiation specimens are very important materials to establish of "Evaluation of Irradiation Damage Indicator" in this research. For the acquisition of the examination specimens irradiated by the JOYO and JRR-3, we summarized about the overall plan, the work process and the results for the study to utilize these reactors and some facilities of hot laboratory (WASTEF, JMTR-HL, MMF and FMF) of the Oarai Research-and-Development Center and the Nuclear Science Research Institute in the Japan Atomic Energy Agency.
Ozawa, Masaki; Suzuki, Tatsuya*; Koyama, Shinichi; Yamagishi, Isao; Fujita, Reiko*; Okada, Ken*; Tatenuma, Katsuyoshi*; Mimura, Hitoshi*; Fujii, Yasuhiko*
Proceedings of International Conference on Advanced Nuclear Fuel Cycle; Sustainable Options & Industrial Perspectives (Global 2009) (CD-ROM), p.1117 - 1126, 2009/09
Tobita, Kenji; Nishio, Satoshi; Enoeda, Mikio; Kawashima, Hisato; Kurita, Genichi; Tanigawa, Hiroyasu; Nakamura, Hirofumi; Honda, Mitsuru; Saito, Ai*; Sato, Satoshi; et al.
Nuclear Fusion, 49(7), p.075029_1 - 075029_10, 2009/07
Times Cited Count：141 Percentile：97.50(Physics, Fluids & Plasmas)Recent design study on SlimCS focused mainly on the torus configuration including blanket, divertor, materials and maintenance scheme. For vertical stability of elongated plasma and high beta access, a sector-wide conducting shell is arranged in between replaceable and permanent blanket. The reactor adopts pressurized-water-cooled solid breeding blanket. Compared with the previous advanced concept with supercritical water, the design options satisfying tritium self-sufficiency are relatively scarce. Considered divertor technology and materials, an allowable heat load to the divertor plate should be 8 MW/m or lower, which can be a critical constraint for determining a handling power of DEMO (a combination of alpha heating power and external input power for current drive).
TiO
pebble bed for a test blanket module in JAEATanigawa, Hisashi; Hoshino, Tsuyoshi; Kawamura, Yoshinori; Nakamichi, Masaru; Ochiai, Kentaro; Akiba, Masato; Ando, Masami; Enoeda, Mikio; Ezato, Koichiro; Hayashi, Kimio; et al.
Nuclear Fusion, 49(5), p.055021_1 - 055021_6, 2009/05
Times Cited Count：23 Percentile：62.74(Physics, Fluids & Plasmas)This paper presents recent achievements of the research activities for the TBM being developed in JAEA, focusing on the pebble bed of the tritium breeder materials and tritium behaviour. For the breeder material, the chemical stability of LiTiO has been improved by LiO additives. In order to analyze the pebble bed behaviour, thermo-mechanical properties of the LiTiO pebble bed has been experimentally obtained. In order to verify nuclear properties of the pebble bed, the activation foil method has been proposed and a preliminary experiment has been conducted. For the tritium behaviour, the chemical densified coating method has been well developed and tritium recovery system has been modified taking account of the design change of the TBM.
Ozawa, Tatsuya; Maeda, Toshikatsu; Mizuno, Tsuyoshi; Bamba, Tsunetaka; Nakayama, Shinichi; Hotta, Katsutoshi*
JAEA-Technology 2006-001, 11 Pages, 2006/02
JAEA-Technology-2006-001.pdf:2.2MB
Melting treatment is a candidate solidification technique for nonflammable low-level radioactive wastes including metals, incineration ashes, and glasses. Simulated incineration ashes of a wide range of chemical compositions were molten at 1,600C to produce lab-scale slag form. No visible pores and separated phases were observed in the slag specimens. It was found by optical observation that some precipitates and small voids were uniformly distributed in many of the specimens. The precipitates were identified to be iron oxides by XRD analysis. The present tests indicate that melting treatment is technically capable to produce stable slag from incineration ashes, which is one of representative TRU-cotaminated radioactive wastes.
Maeda, Toshikatsu; Bamba, Tsunetaka*; Hotta, Katsutoshi*; Mizuno, Tsuyoshi*; Ozawa, Tatsuya
Nihon Genshiryoku Gakkai Wabun Rombunshi, 4(4), p.242 - 247, 2005/12
no abstracts in English
