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Al
and Nd
Pd
Ge
Metoki, Naoto; Shibata, Kaoru; Matsuura, Masato*; Kitazawa, Hideaki*; Suzuki, Hiroyuki*; Yamauchi, Hiroki; Hagihara, Masato; Frontzek, M. D.*; Matsuda, Masaaki*
Journal of the Physical Society of Japan, 91(5), p.054710_1 - 054710_6, 2022/05
Times Cited Count：0 Percentile：0(Physics, Multidisciplinary)Hyperfine splitting of Nd nuclei in NdPdAl has been studied by means of high-resolution neutron spectroscopy. We observed inelastic peaks at 
eV coming from the hyperfine splitting in the magnetically ordered phase due to the hyperfine interactions between Nd nuclei (
=7/2) and the 4
electrons with 
ground state composed of mainly 
. At very low temperatures, nuclear spin of Nd is polarized with increasing occupation probability of low energy levels and contributes to the enhancement of the antiferromagnetic Bragg intensities: the elastic non-spin-flip channel is dominant. As an application of this phenomenon, we determined the Nd moment and hyperfine splitting from the temperature dependence of an antiferromagnetic Bragg intensities for NdPdGe.
Goto, Minoru; Okumura, Keisuke; Nakagawa, Shigeaki; Inaba, Yoshitomo; Matsuura, Hideaki*; Nakaya, Hiroyuki*; Katayama, Kazunari*
Fusion Engineering and Design, 136(Part A), p.357 - 361, 2018/11
Times Cited Count：6 Percentile：52.24(Nuclear Science & Technology)A High Temperature Gas-cooled Reactor (HTGR) is proposed as a tritium production device, which has the potential to produce a large amount of tritium using 
Li(n,
)T reaction. In the HTGR design, generally, boron is loaded into the core as a burnable poison to suppress excess reactivity. In this study, lithium is loaded into the HTGR core instead of boron and is used as a burnable poison aiming to produce thermal energy and tritium simultaneously. The nuclear characteristics and the fuel temperature were calculated to confirm the feasibility of the lithium-loaded HTGR. It was shown that the calculation results satisfied the design requirements and hence the feasibility was confirmed for the lithium-loaded HTGR, which produce thermal energy and tritium.
Kora, Kazuki*; Nakaya, Hiroyuki*; Matsuura, Hideaki*; Goto, Minoru; Nakagawa, Shigeaki; Shimakawa, Satoshi*
Nuclear Engineering and Design, 300, p.330 - 338, 2016/04
Times Cited Count：6 Percentile：49.05(Nuclear Science & Technology)In order to investigate the potential of high temperature gas-cooled reactors (HTGRs) for transmutation of long-lived fission products (LLFPs), numerical simulation of four types of HTGRs were carried out. In addition to the gas-turbine high temperature reactor system "GTHTR300", a small modular HTGR plant "HTR50S" and two types of plutonium burner HTGRs "Clean Burn with MA" and "Clean Burn without MA" were considered. The simulation results show that an early realization of LLFP transmutation using a compact HTGR may be possible since the HTR50S can transmute fair amount of LLFPs for its thermal output. The Clean Burn with MA can transmute a limited amount of LLFPs. However, an efficient LLFP transmutation using the Clean Burn without MA seems to be convincing as it is able to achieve very high burn-ups and produce LLFP transmutation more than GTHTR300. Based on these results, we propose utilization of variety of HTGRs for LLFP transmutation and storage.
Kawamoto, Yasuko*; Nakaya, Hiroyuki*; Matsuura, Hideaki*; Katayama, Kazunari*; Goto, Minoru; Nakagawa, Shigeaki
Fusion Science and Technology, 68(2), p.397 - 401, 2015/09
Times Cited Count：1 Percentile：9.71(Nuclear Science & Technology)To start up a fusion reactor, it is necessary to provide a sufficient amount of tritium from an external device. Herein, methods for supplying a fusion reactor with tritium are discussed. Use of a high temperature gas cooled reactor (HTGR) as a tritium production device has been proposed. So far, the analyses have been focused only on the operation in which fuel is periodically exchanged (batch) using the block type HTGR. In the pebble bed type HTGR, it is possible to design an operation that has no time loss for refueling. The pebble bed type HTGR (PBMR) and the block type HTGR (GTHTR300) are assumed as the calculation and comparison targets. Simulation is made using the continuous-energy Monte Carlo transport code MVPBURN. It is shown that the continuous operation using the pebble bed type HTGR has almost the same tritium productivity compared with the batch operation using the block type HGTR. The issues for pebble bed type HTGR as a tritium production device are discussed.
Nakaya, Hiroyuki*; Matsuura, Hideaki*; Katayama, Kazunari*; Goto, Minoru; Nakagawa, Shigeaki
Proceedings of 2015 International Congress on Advances in Nuclear Power Plants (ICAPP 2015) (CD-ROM), p.398 - 402, 2015/05
The performance of tritium production for fusion reactor using High-Temperature Gas-cooled Reactor (HTGR) is studied. An influence of Li concentration on tritium production performance using HTGR is estimated. Li compound is loaded in the reactor core using Li rod consisting cylindrical Li compound in cladding tube. A Gas Turbine High-Temperature Reactor of 300 MWe nominal capacity (GTHTR300) with 600 MW thermal output power is assumed as HTGR. An amount of tritium production is estimated by burn-up calculations using the continuous-energy Monte Carlo transport code MVP-BURN. The amount of tritium outflow is estimated from equilibrium solution for the tritium diffusion equation in the cladding tube. Even if 6Li is enriched, the GTHTR300 can produce 500 g of tritium over 180-day operation without increasing the amount of required Li. The amount of tritium outflow is decreased by 20-50%.
Kora, Kazuki*; Nakaya, Hiroyuki*; Kubo, Kotaro*; Matsuura, Hideaki*; Shimakawa, Satoshi; Goto, Minoru; Nakagawa, Shigeaki
Proceedings of International Conference on the Physics of Reactors; The Role of Reactor Physics toward a Sustainable Future (PHYSOR 2014) (CD-ROM), 12 Pages, 2014/09
In this study, the capability of HTGR as LLFP transmuter was evaluated in terms of neutron economy. Considering gas turbine high-temperature reactor with 300 MWe nominal capacity (GTHTR300) as HTGR, transmutations of four types of LLFP nuclide were estimated using Monte Carlo transport code MVP and ORIGEN. In addition, burn-up simulations for whole-core region were carried out using MVP-BURN. It was numerically shown that the neutron fluxes change significantly depending on the arrangement of LLFP in the core. When 15 t of LLFP is placed in an ideal manner, the GTHTR300 can sustain sufficient reactivity for one year while transmuting up to 30 kg per year. Additionally, there are more space available for storing larger amount of LLFP without affecting the reactivity. These results suggest that there is a possibility of using GTHTR300 as both LLFP storage and transmuter.
Na)TiO
Matsuura, Masato*; Iida, Hiroyuki*; Hirota, Kazuma*; Owada, Kenji; Noguchi, Yuji*; Miyayama, Masaru*
Physical Review B, 87(6), p.064109_1 - 064109_10, 2013/02
Times Cited Count：30 Percentile：75.22(Materials Science, Multidisciplinary)Neutron-scattering studies of (BiNa)TiO (BNT) have been performed to elucidate the microscopic mechanism of the broad maximum in the temperature dependence of the dielectric constant at Tm 
600 K and the reduction in the piezoelectric properties above the depolarization temperature, 460 480 K. We observed diffuse scattering near the 
point below 700 K, which competes with the superlattice peak at the M point of the tetragonal phase but coexists with the superlattice peak at the R point of the rhombohedral phase. The diffuse scattering shows an anisotropic Q shape extending along the 
100
direction transverse to the scattering vector Q, which is explained by atomic shifts bridging the tetragonal and rhombohedral structures. We propose that the broad maximum in the dielectric constant is associated with a diffusive first-order transition between the competing tetragonal and rhombohedral phases. In addition, we found that the diffuse scattering is reduced for single crystals grown under high oxygen pressure, which suggests an analogy with the central peak in hydrogen-reduced SrTiO. Inelastic neutron scattering near the point reveals a heavily overdamped soft mode similar to those reported in lead-based relaxors, the "waterfall" feature. Moreover, a damped soft transverse acoustic mode is observed for the 100 direction as the anisotropic diffuse scattering, indicating phase instabilities with the same origin as that of the diffuse scattering. The recovery of the soft mode is observed near the depolarization temperature, which coincides with the disappearance of the superlattice peak at the M point. These results indicate that the depolarization and the waterfall feature originate in the dynamic nature of ferroelectric clusters in the coexisting tetragonal/rhombohedral phase.
Sr
CuO
Matsuura, Masato*; Fujita, Masaki*; Hiraka, Haruhiro*; Kofu, Maiko*; Kimura, Hiroyuki*; Wakimoto, Shuichi; Perring, T. G.*; Frost, C. D.*; Yamada, Kazuyoshi*
Physical Review B, 86(13), p.134529_1 - 134529_8, 2012/10
Times Cited Count：7 Percentile：31.82(Materials Science, Multidisciplinary)Kotaki, Hideyuki; Daito, Izuru; Kando, Masaki; Hayashi, Yukio; Kawase, Keigo; Kameshima, Takashi*; Fukuda, Yuji; Homma, Takayuki; Ma, J.*; Chen, L. M.*; et al.
Physical Review Letters, 103(19), p.194803_1 - 194803_4, 2009/11
Times Cited Count：59 Percentile：88.21(Physics, Multidisciplinary)Ando, Hiroshi*; Taga, Junichi*; Matsuura, Hiroyuki*; Yasumura, Keijiro*; Minami, Yuji*; Tomura, Hisashi*; Tomita, Toshihide*
PNC TJ101 84-15, 370 Pages, 1984/10
None
Ando, Hiroshi*; Taga, Junichi*; Matsuura, Hiroyuki*; *; Minami, Yuji*; *
PNC TJ101 83-03, 129 Pages, 1983/05
no abstracts in English
Kaminaga, Norihisa; Nihei, Yasuo; Kimura, Yasuhiko; Kikuchi, Hiroyuki; Takahashi, Ishio; Matsuura, Takanobu; Suzuki, Kazuhiro; Kitamura, Toshikatsu; Sato, Yasuo; Hatanaka, Kazuo*
no journal, ,
no abstracts in English
Kotaki, Hideyuki; Daito, Izuru; Kando, Masaki; Hayashi, Yukio; Kawase, Keigo; Kameshima, Takashi; Fukuda, Yuji; Homma, Takayuki; Ma, J.*; Chen, L. M.*; et al.
no journal, ,
no abstracts in English
Kotaki, Hideyuki; Daito, Izuru; Kando, Masaki; Hayashi, Yukio; Kawase, Keigo; Kameshima, Takashi; Fukuda, Yuji; Homma, Takayuki; Ma, J.*; Chen, L. M.*; et al.
no journal, ,
Kotaki, Hideyuki; Mori, Michiaki; Kando, Masaki; Hayashi, Yukio; Kawase, Keigo; Homma, Takayuki; Koga, J. K.; Daito, Izuru; Kameshima, Takashi*; Fukuda, Yuji; et al.
no journal, ,
no abstracts in English
Yasumoto, Takashi*; Matsuura, Hideaki*; Shimakawa, Satoshi; Nakao, Yasuyuki*; Kochi, Shohei*; Nakaya, Hiroyuki*; Goto, Minoru; Nakagawa, Shigeaki
no journal, ,
no abstracts in English
Yasumoto, Takashi*; Matsuura, Hideaki*; Shimakawa, Satoshi; Nakao, Yasuyuki*; Kochi, Shohei*; Nakaya, Hiroyuki*; Goto, Minoru; Nakagawa, Shigeaki; Nishikawa, Masabumi*
no journal, ,
no abstracts in English
Kochi, Shohei*; Nakaya, Hiroyuki*; Shimakawa, Satoshi; Matsuura, Hideaki*; Yasumoto, Takashi*; Nakao, Yasuyuki*; Goto, Minoru; Nakagawa, Shigeaki
no journal, ,
no abstracts in English
Matsuura, Hideaki*; Yasumoto, Takashi*; Shimakawa, Satoshi; Kochi, Shohei*; Nakaya, Hiroyuki*; Nakao, Yasuyuki*; Goto, Minoru; Nakagawa, Shigeaki; Nishikawa, Masabumi*
no journal, ,
no abstracts in English
Kakurai, Kazuhisa; Wakimoto, Shuichi; Matsuda, Masaaki*; Ishiwata, Shintaro*; Okuyama, Daisuke*; Taguchi, Yasujiro*; Tokura, Yoshiki*; Nishi, Masakazu*; Nakajima, Taro*; Mitsuda, Setsuo*; et al.
no journal, ,
