Ferroaxial transitions in glaserite-type compounds; Database screening, phonon calculations, and experimental verification

Yamagishi, Shigetada*; Hayashida, Takeshi*; Misawa, Ryusuke*; Kimura, Kenta*; Hagihara, Masato; Murata, Tomoki*; Hirose, Sakyo*; Kimura, Tsuyoshi*

Chemistry of Materials, 35(2), p.747 - 754, 2023/01

https://doi.org/10.1021/acs.chemmater.2c03540

Coexistence of magnetoelectric and antiferroelectric-like orders in MnTaO

Kimura, Kenta*; Yagi, Naoki*; Hasegawa, Shunsuke*; Hagihara, Masato; Miyake, Atsushi*; Tokunaga, Masashi*; Cao, H.*; Masuda, Takatsugu*; Kimura, Tsuyoshi*

Inorganic Chemistry, 60(20), p.15078 - 15084, 2021/10

https://doi.org/10.1021/acs.inorgchem.1c02461

Conceptual design of multipurpose compact research reactor; Annual report FY2011

Watahiki, Shunsuke; Hanakawa, Hiroki; Imaizumi, Tomomi; Nagata, Hiroshi; Ide, Hiroshi; Komukai, Bunsaku; Kimura, Nobuaki; Miyauchi, Masaru; Ito, Masayasu; Nishikata, Kaori; et al.

JAEA-Technology 2013-021, 43 Pages, 2013/07

JAEA-Technology-2013-021.pdf:5.12MB

The number of research reactors in the world is decreasing because of their aging. On the other hand, the necessity of research reactor, which is used for human resources development, progress of the science and technology, industrial use and safety research is increasing for the countries which are planning to introduce the nuclear power plants. From above background, the Neutron Irradiation and Testing Reactor Center began to discuss a basic concept of Multipurpose Compact Research Reactor (MCRR) for education and training, etc., on 2010 to 2012. This activity is also expected to contribute to design tool improvement and human resource development in the center. In 2011, design study of reactor core, irradiation facilities with high versatility and practicality, and hot laboratory equipment for the production of Mo-99 was carried out. As the result of design study of reactor core, subcriticality and operation time of the reactor in consideration of an irradiation capsule, and about the transient response of the reactor to the reactivity disturbance during automatic control operation, it was possible to do automatic operation of MCRR, was confirmed. As the result of design study of irradiation facilities, it was confirmed that the implementation of an efficient mass production radioisotope Mo-99 can be expected. As the result of design study with hot laboratory facilities, Mo-99 production, RI export devised considered cell and facilities for exporting the specimens quickly was designed.

Current status of JMTR

Ishihara, Masahiro; Kimura, Nobuaki; Takemoto, Noriyuki; Ooka, Makoto; Kaminaga, Masanori; Kusunoki, Tsuyoshi; Komori, Yoshihiro; Suzuki, Masahide

Proceedings of 5th International Symposium on Material Testing Reactors (ISMTR-5) (Internet), 7 Pages, 2012/10

http://www.murr.missouri.edu/ismtr/papercall/Papers/JAEA/Ishihara_M=1_PAPER_JMTR%20Status.pdf

The JMTR has been utilized for fuel/material irradiation examinations of LWRs, HTGR, fusion reactor as well as for RI productions. The refurbishment of the JMTR was started from the beginning of JFY 2007, and finished in March 2011 as planned schedule. Unfortunately, at the end of the JFY 2010 on March 11, the Great-Eastern-Japan-Earthquake occurred, and functional tests before the JMTR restart were delayed by the earthquake. Moreover, a detail inspection found some damages such as small cracks in the concrete structure, ground sinking around the reactor building. Consequently, the restart will delay from June 2011. Now, the safety evaluation of the facility after the earthquake disaster is being carried out aiming at the restart of the JMTR. The renewed JMTR will be started from JFY 2012 and operated for a period of about 20 years until around JFY 2030. The usability improvement of the JMTR is also discussed with users as the preparations for re-operation.

Japanese contribution to the DEMO-R&D program under the Broader Approach activities

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

https://doi.org/10.1016/j.fusengdes.2011.07.004

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.

Experimental evidence of nonthermal acceleration of relativistic electrons by an intensive laser pulse

Kuramitsu, Yasuhiro*; Nakanii, Nobuhiko*; Kondo, Kiminori; Sakawa, Yoichi*; Mori, Yoshitaka*; Miura, Eisuke*; Tsuji, Kazuki*; Kimura, Kazuya*; Fukumochi, Shuji*; Kashihara, Mamoru*; et al.

Physical Review E, 83(2), p.026401_1 - 026401_6, 2011/02

https://doi.org/10.1103/PhysRevE.83.026401

An energy distribution function of energetic particles in the universe or cosmic rays is well represented by a power-law spectrum, therefore, nonthermal acceleration is essential to understand the origin of cosmic rays. A possible candidate for the origin of cosmic rays is wakefield acceleration at relativistic astrophysical perpendicular shocks. Substituting an intensive laser pulse for the large amplitude light waves, we performed a model experiment of the shock environments in a laboratory plasma.

Model experiment of cosmic ray acceleration due to an incoherent wakefield induced by an intense laser pulse

Kuramitsu, Yasuhiro*; Nakanii, Nobuhiko*; Kondo, Kiminori; Sakawa, Yoichi*; Mori, Yoshitaka*; Miura, Eisuke*; Tsuji, Kazuki*; Kimura, Kazuya*; Fukumochi, Shuji*; Kashihara, Mamoru*; et al.

Physics of Plasmas, 18(1), p.010701_1 - 010701_4, 2011/01

https://doi.org/10.1063/1.3528434

Substituting an intensive laser pulse for the large amplitude light waves, we performed a model experiment of the shock environments in a laboratory plasma. An intensive laser pulse was propagated in a plasma tube created by imploding a hollow polystyrene cylinder, as the large amplitude light waves propagated in the upstream plasma at an astrophysical shock. Nonthermal electrons were generated, and the energy distribution functions of the electrons have a power-law component with an index of 2.

Synergistic extraction of Am(III) and Eu(III) by tris(2-pyridylmethyl)amine with various anions in 1,2-dichloroethane

Ishimori, Kenichiro; Watanabe, Masayuki; Yaita, Tsuyoshi; Kimura, Takaumi; Yamada, Takashi*; Shinoda, Satoshi*; Tsukube, Hiroshi*

Solvent Extraction and Ion Exchange, 27(4), p.489 - 500, 2009/07

https://doi.org/10.1080/07366290902966944

The remarkable enhancements of the extraction efficiency of Am(III) and Eu(III) and the separation efficiency between Am(III) and Eu(III) were achieved through changes in counter anions and/or organic solvents, in the solvent extraction of Am(III) and Eu(III) with a tripodal ligand, tris(2-pryidylmethyl)amine (tpa). The separation factor (Am/Eu), which is defined as the ratio between the distribution ratios of Am(III) and Eu(III), ranged from 10 to 50 using various combinations of counter anions and organic solvents. The extraction equilibria of Am(III) and Eu(III) with tpa in 1,2-dichloroethane were determined in detail through slope analyses in order to elucidate the mechanism of separation and identify the extracted species.

Crystallization and preliminary neutron diffraction studies of HIV-1 protease cocrystallized with inhibitor KNI-272

Matsumura, Hiroyoshi*; Adachi, Motoyasu; Sugiyama, Shigeru*; Okada, Shino*; Yamakami, Megumi*; Tamada, Taro; Hidaka, Koshi*; Hayashi, Yoshio*; Kimura, Toru*; Kiso, Yoshiaki*; et al.

Acta Crystallographica Section F, 64(11), p.1003 - 1006, 2008/11

https://doi.org/10.1107/S1744309108029679

This paper reports the crystallization and preliminary neutron diffraction measurements of HIV-1 protease, a potential target for anti-HIV therapy, complexed with an inhibitor (KNI-272). The aim of this neutron diffraction study is to obtain structural information about the H atoms and to determine the protonation states of the residues within the active site. The crystal was grown to a size of 1.4 mm by repeated macroseeding and a slow-cooling method using a two-liquid system. Neutron diffraction data were collected at room temperature using a BIX-4 diffractometer at the JRR-3 research reactor of the Japan Atomic Energy Agency (JAEA). The data set was integrated and scaled to 2.3 resolution in space group P2(1)2(1)2, with unit-cell parameters a = 59.5, b = 87.4, c = 46.8 .

Preparation of acellular arteries by irradiation

Fujisato, Toshiya*; Kikuchi, Masahiro; Sakashita, Tetsuya; Funayama, Tomoo; Kobayashi, Yasuhiko; Funamoto, Seiichi*; Kimura, Tsuyoshi*; Kishida, Akio*; Yamaoka, Tetsuji*

JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 119, 2008/03

https://jopss.jaea.go.jp/pdfdata/JAEA-Review-2007-060.pdf

Synthetic materials, such as ePTFE or Dacron are not suitable for reconstructing the small-diameter arteries. In contrast, tissue engineering (TE) graft has been attracting great attention recently. One of the promising approaches of TE grafts is using acellular tissues. The acellular scaffold may have the same structure and characteristics as the natural tissue and can be replaced with the host tissues. In this study, we prepared the acellular scaffold using irradiation, which is expected to induce the apoptosis of the cells.