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Katayama, Ryo*; Kako, Eiji*; Yamaguchi, Seiya*; Michizono, Shinichiro*; Umemori, Kensei*; Kondo, Yasuhiro
Physical Review Accelerators and Beams (Internet), 25(2), p.021601_1 - 021601_18, 2022/02
Times Cited Count:4 Percentile:45.59(Physics, Nuclear)We investigated the feasibility on the application of a superconducting radio frequency (SRF) niobium cavity to an accelerator-based neutron source for boron neutron capture therapy (BNCT). This paper presents a first feasibility study on the application of a SRF niobium cavity to an accelerator-based neutron source for BNCT, assuming that a superconducting radio frequency quadrupole (SC-RFQ) composed of pure bulk niobium at 4.2 K accelerates the proton/deuteron beams to a beryllium or lithium target for the neutron production of BNCT. We evaluated the feasibility on the following three criteria: comparison of the cooling capacity of the refrigerator to the amount of heat, power consumption of AC, and size of the BNCT system. This study demonstrated that the application of the SRF cavity for the rf-linac-based neutron source of BNCT is feasible, and the 2.5 MeV deuteron SC-RFQ and lithium target system is the optimum.

Mo
O
(
= In, Sc)Iida, Kazuki*; Yoshida, Hiroyuki*; Okabe, Hirotaka*; Katayama, Naoyuki*; Ishii, Yuto*; Koda, Akihiro*; Inamura, Yasuhiro; Murai, Naoki; Ishikado, Motoyuki*; Kadono, Ryosuke*; et al.
Scientific Reports (Internet), 9(1), p.1826_1 - 1826_9, 2019/02
Times Cited Count:15 Percentile:65.69(Multidisciplinary Sciences)Ohgama, Kazuya; Ando, Yoko; Yamaguchi, Mika; Ikuta, Yuko; Shinohara, Nobuo; Murakami, Hiroyuki; Yamashita, Kiyonobu; Uesaka, Mitsuru*; Demachi, Kazuyuki*; Komiyama, Ryoichi*; et al.
JAEA-Review 2013-004, 76 Pages, 2013/05
JAEA together with the Japan Nuclear Human Resource Development Network (JN-HRD Net), the University of Tokyo (UT) and the Japan Atomic Industrial Forum (JAIF) cohosted the IAEA-Nuclear Energy Management School in Tokai Village, aiming that Japan will be the center of nuclear HRD in the Asian region. In the school, not only lectures by IAEA experts, but also lectures by Japanese experts and technical visits were included for foreign participants. The school contributed to the internationalization of Japanese young professionals, development of nuclear human resource of other countries, and enhancement of cooperation between IAEA and Japan. Additionally, collaborative relationship within JN-HRD Net was strengthened by the school. In this report, findings obtained during the preparatory work and the school period are reported for future international nuclear HRD activities in Japan.
Na
Li
)TiO
Fukunaga, Masanori; Yoneda, Yasuhiro; Fukuyama, Ryota*; Saito, Hiroyuki; Ikeda, Naoshi*; Katayama, Yoshinori
Transactions of the Materials Research Society of Japan, 35(1), p.111 - 114, 2010/03
High-pressure synthesis of bismuth based perovskite (Bi
Na
Li
)TiO
(BNLT) (
=0.1, 0.15, 0.2, 0.25, 0.4, 0.5) was demonstrated. Single phase BNLTs with perovskite structure were successfully synthesized for 
0.1 by the solid state reaction method. The solid phase reaction occurred in the pressure range of 6-10 GPa, and in the temperature range of 800-1200
C. Two thermal anomalies were observed in single phase perovskite BNLT (
=0.1) as well as (Bi,Na)TiO
. The cusp like anomaly at 210
C was assigned to a rhombohedral-tetragonal structural phase transition. The finished products of 
0.2 included three kinds of impurities, which were affected by the selection of starting materials.
Otani, Eiji*; Suzuki, Akio*; Ando, Ryota*; Urakawa, Satoru*; Funakoshi, Kenichi*; Katayama, Yoshinori
Advances in High-Pressure Technology for Geophysical Applications, p.195 - 209, 2005/09
This paper summarizes the techniques for the viscosity and density measurements of silicate melt and glasses at high pressure and temperature by using the X-ray radiography and absorption techniques in the third generation synchrotron radiation facility, SPring-8, Japan. The falling sphere method using in situ X-ray radiography makes it possible to measure the viscosity of silicate melts to the pressures above 6 GPa at high temperature. We summarize the details of the experimental technique of the viscosity measurement, and the results of the measurements of some silicate melts such as the albite and diopside-jadeite systems. X-ray absorption method is applied to measure the density of the silicate glasses such as the basaltic glass and iron sodium disilicate glass up to 5 GPa at high temperature. A diamond capsule, which is not reactive with the glass, is used for the density measurement of the glasses. The present density measurement of the glasses indicates that this method is useful for measurement of the density of silicate melts at high pressure and temperature.
Higuchi, Kensuke*; Kimura, Kakuryo*; Mizuno, Akitoshi*; Watanabe, Masahito*; Katayama, Yoshinori; Kuribayashi, Kazuhiko*
Measurement Science and Technology, 16(2), p.381 - 385, 2005/02
Times Cited Count:45 Percentile:86.42(Engineering, Multidisciplinary)X-ray diffraction and density measurements have been simultaneously performed to investigate the atomic structure of molten silicon in wide temperature range including undercooling region by using the electromagnetic levitation technique. The density was obtained from the mass and the shape of levitated sample by non-contact method based on the image analysis technique. X-ray diffraction experiments were performed by using the synchrotron radiation at SPring8, Japan. From structural analysis of undercooled molten silicon, first nearest neighbour coordination numbers and interatomic distances were about 5 and 2.48
with no dependence on temperature in the range of 1900-1550 K. We conclude as a result that the short-range order based on tetrahedral bonds of undercooled molten silicon does not change with the degree of undercoolings but medium-range order changes by the degree of undercoolings.
Yoneda, Yasuhiro; Mizuki, Junichiro; Katayama, Ryoko*; Yagi, Kenichiro*; Terauchi, Hikaru*; Hamazaki, Shinichi*; Takashige, Masaaki*
Applied Physics Letters, 83(2), p.275 - 277, 2003/07
Times Cited Count:18 Percentile:56.34(Physics, Applied)We observed an intermediate structure during the re-crystallization process from the amorphous state of Bi
Ti
O
prepared by rapid quenching. The intermediate structure which appears during the re-crystallization process consists of two phases; one is pyrochlore Bi
Ti
O
phase and the other is a stacking-fault induced structure under the excessive Bi condition. The microstructure of the stacking-fault induced structure was investigated by synchrotron X-ray diffraction. In the case of a large number of Bi
O
, some are inserted between the pseudo-perovskite layers of Bi
Ti
O
, and a non-stoichiometric Bi
WO
-like structure is stabilized.
850
C) conditionsOkamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru; et al.
no journal, ,
Currently, many researches to achieve DT nuclear-fusion power generation are under proceeding but the method to provide initial tritium loaded to fusion prototype reactor is not clear. The method of tritium production by using high temperature gas-cooled reactor (HTGR) was proposed. In this method, lithium rods are loaded to the reactor core of HTGR and tritium is produced by
Li(n,
)T reaction. And the method to reduce the spilled tritium by using the lithium rod with zirconium layer was proposed. In this study, the experiments to evaluate the performance of hydrogen absorption in the zirconium layer were conducted under the temperature condition more than 700
C which is the normal operation condition for the very high temperature gas-cooled reactor (VHTR). The experimental result concerning solubility and diffusion factor of hydrogen in the zirconium layer will be presented and discussed.
Okamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru
no journal, ,
A study on tritium production using a high-temperature gas-cooled reactor has been carried out and it was proposed that zirconium is loaded into the lithium irradiation capsule to confine tritium within the irradiation capsule under high temperature condition. In this study, zirconium loading method was examined by numerical calculations to improve the tritium confinement. As a result, it was found that improvement in the tritium confinement can be expected by loading spherical zirconium into the irradiation capsule.
Nakagawa, Kyoichi*; Matsuura, Hideaki*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Hamamoto, Shimpei; Ishitsuka, Etsuo; Nakagawa, Shigeaki; Tobita, Kenji*; et al.
no journal, ,
The containment of tritium by using zirconium in the lithium rod applied to the tritium production in the HTGR has been investigated. Considering the temperature distribution on the reactor core, the containment performance to tritium was evaluated through the measurement of the Zr hydrogen absorption rate in its temperature range.
C) conditionsOkamoto, Ryo*; Matsuura, Hideaki*; Ida, Yuma*; Koga, Yuki*; Suganuma, Takuro*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; et al.
no journal, ,
It has been proposed that lithium rods, which are cylindrical lithium compounds, are loaded into a HTGR and tritium for initial fusion reactors is produced by
Li(n,
)T reaction. In this study, it was discussed that the lithium rods are covered with zirconium layers to prevent the produced tritium leak. The solubility and diffusion coefficient of hydrogen in zirconium were measured and the effectiveness of the zirconium layers on prevention of tritium leakage was estimated with the measured values. As a result, the tritium leakage ratio with the zirconium layers was estimated two orders lower than that without the zirconium layers, and hence it was considered that the zirconium layer is very effective on the prevention of the tritium leakage.
Koga, Yuki*; Matsuura, Hideaki*; Okamoto, Ryo*; Ida, Yuma*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Nagasumi, Satoru; et al.
no journal, ,
Large quantity of tritium is demanded for starting up of fusion reactor and engineering test using tritium for fusion blanket system. Tritium production, by
Li(n,
)T reaction using the high temperature gas-cooled reactor (HTGR), has been proposed and the method to produce tritium by loading the lithium rods as burnable poison in the reactor core has been studied. In this presentation, the design of lithium rods to be loaded to High Temperature engineering Test Reactor (HTTR) and its irradiation test plan to demonstrate tritium production are presented.
Suganuma, Takuro*; Matsuura, Hideaki*; Okamoto, Ryo*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Tobita, Kenji*
no journal, ,
A study on the confinement of tritium, which is a fuel for fusion reactors and is produced by a HTGR, has been conducted for high temperature condition. The tritium is confined in the irradiation capsule with a zirconium layer. The relation between a H/Zr ratio and an apparent diffusion coefficient of tritium in the zirconium layer is needed to evaluate the tritium confinement performance of the irradiation capsule. This relation was examined with a experiment using deuteron. As a result, the apparent diffusion coefficient deceases with an increase of the H/Zr ratio. This phenomena should be caused by a generation of hydrogen. After that, the analysis for an amount of the release of the tritium from the irradiation capsule will be calculated using obtained data to evaluate the containment performance of the irradiation capsule.
Arai, Yosuke*; Kuroda, Kenta*; Tsutsui, Satoshi*; Hirai, Daigoro*; Tanaka, Hiroaki*; Yuyang, D.*; Iwata, Takuma*; Katayama, Kazu*; Shin, S.*; Kubota, Masato; et al.
no journal, ,
no abstracts in English
Okamoto, Ryo*; Matsuura, Hideaki*; Koga, Yuki*; Suganuma, Takuro*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Tobita, Kenji*
no journal, ,
Currently, the method to reduce the spilled tritium by using the lithium rod with zirconium layer under the high temperature condition was proposed in the study of the tritium production by using high temperature gas-cooled reactor (HTGR). In this study, the experiments to evaluate the performance of hydrogen absorption in the zirconium layer were conducted. The experimental result concerning hydrogen absorption properties of zirconium will be presented and discussed.
Ida, Yuma*; Matsuura, Hideaki*; Nagasumi, Satoru*; Koga, Yuki*; Okamoto, Ryo*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo
no journal, ,
Tritium production method using HTGRs (High Temperature Gas-cooled reactors) is studied as the tritium supplying method for initial D-T fusion reactors. In this method, tritium is produced by
Li (n,
)T reaction. The amount of tritium production and the tritium confinement capability were evaluated in case of the irradiation capsule including the Li compound is installed into the HTGRs in the past. In this study, the tritium confinement capability is evaluated for the irradiation capsule with ZrC layer by performing calculations of the amount of tritium leakage. The calculation results showed that the amount of tritium leakage is decreased to one fifth with the ZrC layer.
Arai, Yosuke*; Kuroda, Kenta*; Tsutsui, Satoshi*; Hirai, Daigoro*; Katayama, N.*; Nomoto, Takuya*; Shin, S.*; Kubota, Masato; Haga, Yoshinori; Suzuki, Hiroyuki*; et al.
no journal, ,
no abstracts in English
Arai, Yosuke*; Kuroda, Kenta*; Tsutsui, Satoshi*; Hirai, Daigoro*; Katayama, Wago*; Shin, S.*; Kubota, Masato; Nomoto, Takuya*; Suzuki, Hiroyuki*; Miyasaka, Shigeki*; et al.
no journal, ,
no abstracts in English
Arai, Yosuke*; Kuroda, Kenta*; Nomoto, Takuya*; Hirai, Daigoro*; Katayama, Wago*; Tsutsui, Satoshi*; Tanaka, Hiroaki*; Arita, Masashi*; Shin, S.*; Kubota, Masato; et al.
no journal, ,
no abstracts in English
Koga, Yuki*; Matsuura, Hideaki*; Okamoto, Ryo*; Suganuma, Takuro*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; Tobita, Kenji*
no journal, ,
Production of tritium using a high temperature gas-cooled reactor (HTGR) has been studied for a prior engineering test with tritium handling and for the startup operation of a demonstration fusion reactor. For this purpose, Li-loading rods are installed at the moderator region of the HTGR. The tritium retention capability of Li-loading rod would decline due to high temperature condition from 1100K to 1200K during HTGR rated power operation. Therefore, the zirconium is employed as tritium absorber which is granular and is coated with nickel to prevent from declining the tritium absorption capability due to zirconium oxidation and so on. In this presentation, the design concept of Li-loading rods with granular zirconium coated with nickel and the method of irradiation test by using the HTTR which is a test reactor of HTGR are presented.
Ida, Yuma*; Matsuura, Hideaki*; Nagasumi, Satoru; Okamoto, Ryo*; Koga, Yuki*; Katayama, Kazunari*; Otsuka, Teppei*; Goto, Minoru; Nakagawa, Shigeaki; Ishitsuka, Etsuo; et al.
no journal, ,
Large quantity of tritium is demanded for starting up of fusion reactor and engineering test using tritium for fusion blanket system. However, tritium is very rare and kg order of tritium must be produced artificially. Tritium production, by
Li(n,
)T reaction using the high temperature gas-cooled reactor (HTGR), has been proposed. In this method, loading of Li rods into burnable poison (BP) holes in HTGR is considered. In this paper, the Li rod suited to the demand for the utilization in High Temperature engineering Test Reactor (HTTR) is designed, and tritium production and leakage from Li-rod capsule are evaluated by adjusting the thickness of LiAlO
, alumina, and Zr layers. A scenario of irradiation test supposed to be conducted at HTTR for demonstration of the tritium production and containment performance of the Li rod is presented.