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CoSiYamauchi, Hiroki; Sari, D. P.*; Yasui, Yukio*; Sakakura, Terutoshi*; Kimura, Hiroyuki*; Nakao, Akiko*; Ohara, Takashi; Honda, Takashi*; Kodama, Katsuaki; Igawa, Naoki; et al.
Physical Review Research (Internet), 6(1), p.013144_1 - 013144_9, 2024/02
Kozawa, Tatsuya*; Fujihara, Masayoshi; Uchihara, Takeru*; Mitsuda, Setsuo*; Yano, Shinichiro*; Tamatsukuri, Hiromu; Munakata, Koji*; Nakao, Akiko*
Scientific Reports (Internet), 13, p.13750_1 - 13750_8, 2023/08
Times Cited Count：0 Percentile：0(Multidisciplinary Sciences)In condensed matter physics, pressure is frequently used to modify the stability of both electronic states and atomic arrangements. Under isotropic pressure, the intermetallic compound MnP has recently attracted attention for the interplay between pressure-induced superconductivity and complicated magnetic order in the vicinity. By contrast, we use uniaxial stress, a directional type of pressure, to investigate the effect on the magnetism and crystal structure of this compound. An irreversible magnetisation response induced by uniaxial stress is discovered in MnP at uniaxial stress as low as 0.04 GPa. Neutron diffraction experiments reveal that uniaxial stress forms crystal domains that satisfy pseudo-rotational symmetry unique to the MnP-type structure. The structure of the coexisting domains accounts for the stress-induced magnetism. We term this first discovered phenomenon atomic reconstruction (AR) induced by uniaxial stress. Furthermore, our calculation results provide guidelines on the search for AR candidates. AR allows crystal domain engineering to control anisotropic properties of materials, including dielectricity, elasticity, electrical conduction, magnetism and superconductivity. A wide-ranging exploration of potential AR candidates would ensure that crystal domain engineering yields unconventional methods to design functional multi-domain materials for a wide variety of purposes.
Shamoto, Shinichi; Ito, Takashi; Onishi, Hiroaki; Yamauchi, Hiroki; Inamura, Yasuhiro; Matsuura, Masato*; Akatsu, Mitsuhiro*; Kodama, Katsuaki; Nakao, Akiko*; Moyoshi, Taketo*; et al.
Physical Review B, 97(5), p.054429_1 - 054429_9, 2018/02
Times Cited Count：18 Percentile：65.6(Materials Science, Multidisciplinary)Nuclear and magnetic structure and full magnon dispersions of yttrium iron garnet YFe
O
have been studied by neutron scattering. The lowest-energy dispersion below 14 meV exhibits a quadratic dispersion as expected from ferromagnetic magnons. The imaginary part of 
-integrated dynamical spin susceptibility 
"(
) exhibits a square-root energy-dependence in the low energies. The magnon density of state is estimated from the "() obtained on an absolute scale. The value is consistent with a single chirality mode for the magnon branch expected theoretically.
Nakajima, Kenji; Kawakita, Yukinobu; Ito, Shinichi*; Abe, Jun*; Aizawa, Kazuya; Aoki, Hiroyuki; Endo, Hitoshi*; Fujita, Masaki*; Funakoshi, Kenichi*; Gong, W.*; et al.
Quantum Beam Science (Internet), 1(3), p.9_1 - 9_59, 2017/12
The neutron instruments suite, installed at the spallation neutron source of the Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex (J-PARC), is reviewed. MLF has 23 neutron beam ports and 21 instruments are in operation for user programs or are under commissioning. A unique and challenging instrumental suite in MLF has been realized via combination of a high-performance neutron source, optimized for neutron scattering, and unique instruments using cutting-edge technologies. All instruments are/will serve in world-leading investigations in a broad range of fields, from fundamental physics to industrial applications. In this review, overviews, characteristic features, and typical applications of the individual instruments are mentioned.
in LaCo
Rh
O
investigated by structural phenomenaAsai, Shinichiro*; Okazaki, Ryuji*; Terasaki, Ichiro*; Yasui, Yukio*; Kobayashi, Wataru*; Nakao, Akiko*; Kobayashi, Kensuke*; Kumai, Reiji*; Nakao, Hironori*; Murakami, Yoichi*; et al.
Journal of the Physical Society of Japan, 82(11), p.114606_1 - 114606_6, 2013/11
Times Cited Count：6 Percentile：43.5(Physics, Multidisciplinary)Neutron and synchrotron X-ray diffraction for LaCo RhO have been carried out in order to investigate the structural properties related with the spin state of Co
ions. We have found that the values of the Co(Rh)-O bond lengths in the Co(Rh)O
octahedron of LaCo
Rh
O are nearly identical at 10 K. The lattice volume for the Rh substituted samples decreases with the thermal expansion coefficient similar to that of LaCoO from room temperature, and ceases to decrease around 70 K. These experimental results favor a mixed state consisting of the high-spin state and low-spin state Co ions, and suggest that the high-spin state Co ions are thermally excited in addition to those pinned by the substituted Rh ions.
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.
Matsuda, Norihiro; Iwamoto, Yosuke; Harada, Masahide; Teshigawara, Makoto; Meigo, Shinichiro; Maekawa, Fujio; Oguri, Tomomi*; Nakano, Hideo*; Nakao, Noriaki*; Nakane, Yoshihiro; et al.
JAEA-Technology 2008-030, 150 Pages, 2008/03
JAEA-Technology-2008-030.pdf:20.67MB
Radiation Shielding design/safety analysis required for licensing of the high intensity proton accelerator facility J-PARC (Japan Proton Accelerator Research Complex) is in progress, using various high-energy particle transport codes. Shielding benchmark problems, mainly based on experiments, on thick target neutron yield, beam dump geometry, deep penetration and radiation streaming were prepared and analyzed by the shielding design codes, in order to estimate the code's accuracy. The results of analyses show that the calculation results agree with the experiments within a factor of two on the whole.
Kasahara, Seiji; Kubo, Shinji; Hino, Ryutaro; Onuki, Kaoru; Nomura, Mikihiro*; Nakao, Shinichi*
International Journal of Hydrogen Energy, 32(4), p.489 - 496, 2007/03
Times Cited Count：115 Percentile：91.83(Chemistry, Physical)Japan Atomic Energy Agency (JAEA) has been conducting the research and development on the thermochemical water-splitting IS process for effective hydrogen production using nuclear heat at temperatures close to 1000 
C. Such temperatures can be supplied by High Temperature Gas-cooled Reactor (HTGR). JAEA's activity covers the studies on control of the process for continuous hydrogen production, the processing in HI decomposition procedure and a preliminary screening of corrosion resistant materials for the construction of the process. The present status of the study is hereby presented, with particular attention given to the studies of the flowsheet of the process using membranes for the HI processing.
Kasahara, Seiji; Onuki, Kaoru; Nomura, Mikihiro*; Nakao, Shinichi*
Journal of Chemical Engineering of Japan, 39(5), p.559 - 568, 2006/05
Times Cited Count：12 Percentile：42.39(Engineering, Chemical)Sensitivity analysis of the operation parameters and the chemical properties in the thermochemical hydrogen production IS process (iodine-sulfur process) was carried out for a static flow sheet. These parameters were evaluated by hydrogen production thermal efficiency, mass flow rate or heat exchange based on heat/mass balance. The most important parameters were concentration of HI after the electro-electrodialysis (EED) cell and apparent transport number of proton of the cation exchange membrane in the EED cell. HI concentration operation should be operated carefully because the parameters for optimum thermal efficiency and for optimum flow rate and heat exchange were different. For the chemical properties, composition at the inlet of the HI decomposition procedure and HIx pseudo-azeotropic composition had great effects. HI concentration after the EED cell should be optimized for each composition. Order of priority for assessment of the operation parameters and chemical properties was determined by the evaluation.
Nomura, Mikihiro*; Okuda, Hiroyuki; Kasahara, Seiji; Nakao, Shinichi*
Chemical Engineering Science, 60(24), p.7160 - 7167, 2005/12
Times Cited Count：29 Percentile：66.02(Engineering, Chemical)The Bunsen reaction (SO
+I+2HO=HSO
+2HI) in the water-splitting IS process was examined using an electrochemical cell with a cation exchange membrane. The optimal molalities of anolyte and catholyte were evaluated by total thermal efficiency. The I/HI ratio had little effect on the required total voltage; the I/HI ratio can be reduced to 0.5 without decreasing the efficiency. HI and HSO molality greatly affected the efficiency. Membrane resistances are very important parameters affecting the efficiency. The total thermal efficiency increased by 3.0% by increasing the operating temperature from 313K to 363K.
Nakashima, Hiroshi; Nakane, Yoshihiro; Masukawa, Fumihiro; Matsuda, Norihiro; Oguri, Tomomi*; Nakano, Hideo*; Sasamoto, Nobuo*; Shibata, Tokushi*; Suzuki, Takenori*; Miura, Taichi*; et al.
Radiation Protection Dosimetry, 115(1-4), p.564 - 568, 2005/12
Times Cited Count：8 Percentile：49.16(Environmental Sciences)The High Intensity Proton Accelerator Project, named as J-PARC, is in progress, aiming at studies on the latest basic science and the advancing nuclear technology. In the project, the high-energy proton accelerator complex of the world highest intensity is under construction. In order to establish a reasonable shielding design, both simplified and detailed design methods were used in the shielding design of J-PARC. This paper reviews the present status of the radiation safety design study for J-PARC.
Kasahara, Seiji; Kubo, Shinji; Hino, Ryutaro; Onuki, Kaoru; Nomura, Mikihiro*; Nakao, Shinichi*
Proceedings of AIChE 2005 Spring National Meeting (CD-ROM), 8 Pages, 2005/04
Japan Atomic Energy Research Institute (JAERI) has been conducting the research and development on the thermochemical water-splitting IS process for effective hydrogen production using nuclear heat of close to 1000 C that can be supplied from High Temperature Gas-cooled Reactor (HTGR). The activity covers the studies on the process control for the continuous hydrogen production, the process improvements in the HI decomposition procedure and the preliminary screening of corrosion resistant materials of construction. Present status of the study is presented, especially, focusing on the process flowsheeting study concerning the application of membrane process for the HI processing.
Tanaka, Susumu; Nakashima, Hiroshi; Sakamoto, Yukio; Nakane, Yoshihiro; Meigo, Shinichiro; Tanaka, Shunichi; Nakamura, Takashi*; Takada, Masashi*; Kurosawa, Tadahiro*; Hirayama, Hideo*; et al.
Health Physics, 81(4), p.406 - 418, 2001/10
Times Cited Count：5 Percentile：38.97(Environmental Sciences)no abstracts in English
ray measurements in a target room of several tens MeV Proton FacilityNakashima, Hiroshi; Masumura, Tomomi*; Tanaka, Susumu; Sakamoto, Yukio; Takada, Hiroshi; Tanaka, Shunichi; Nakane, Yoshihiro; Meigo, Shinichiro; Nakamura, Takashi*; Kurosawa, Tadahiro*; et al.
Journal of Nuclear Science and Technology, 37(Suppl.1), p.192 - 196, 2000/03
no abstracts in English
Nakashima, Hiroshi; Masumura, Tomomi*; Tanaka, Susumu; Sakamoto, Yukio; Tanaka, Shunichi; Nakane, Yoshihiro; Meigo, Shinichiro; Nakamura, Takashi*; Kurosawa, Tadahiro*; Hirayama, Hideo*; et al.
Journal of Nuclear Science and Technology, 37(Suppl.1), p.197 - 201, 2000/03
no abstracts in English
; Nakane, Yoshihiro; Sakamoto, Yukio; Nakashima, Hiroshi; Meigo, Shinichiro; Tanaka, Shunichi; Kurosawa, Tadahiro*; Nakamura, Takashi*; Nakao, Noriaki*; Hirayama, Hideo*; et al.
Proc. of 1998 ANS Radiat. Protection and Shielding Division Topical Conf. Technol. for the New Century, 2, p.164 - 169, 1998/00
no abstracts in English
Sakamoto, Yukio; Tanaka, Susumu; ; Nakane, Yoshihiro; Meigo, Shinichiro; Takada, Hiroshi; Tanaka, Shunichi; Takada, M.*; Kurosawa, Tadahiro*; Nakamura, Takashi*; et al.
Genshikaku Kenkyu, 41(3), p.95 - 99, 1996/06
no abstracts in English
Tanaka, Susumu; Nakashima, Hiroshi; Nakane, Yoshihiro; Sakamoto, Yukio; Meigo, Shinichiro; Tanaka, Shunichi; Takada, Masashi*; Kurosawa, Tadahiro*; Nakamura, Takashi*; Nakao, Noriaki*; et al.
Genshikaku Kenkyu, 41(3), p.101 - 112, 1996/06
no abstracts in English
Li(P,n) reaction; Nakao, Noriaki*; Tanaka, Shunichi; Nakamura, Takashi*; Shin, Kazuo*; Tanaka, Susumu; Meigo, Shinichiro; Nakane, Yoshihiro; Takada, Hiroshi; Sakamoto, Yukio; et al.
JAERI-Data/Code 96-005, 46 Pages, 1996/03
JAERI-Data-Code-96-005.pdf:1.54MB
no abstracts in English
; Nakao, Noriaki*; Tanaka, Shunichi; Nakamura, Takashi*; Shin, Kazuo*; Tanaka, Susumu; Takada, Hiroshi; Meigo, Shinichiro; Nakane, Yoshihiro; Sakamoto, Yukio; et al.
Nuclear Science and Engineering, 124(2), p.243 - 257, 1996/00
Times Cited Count：41 Percentile：94.24(Nuclear Science & Technology)no abstracts in English
