Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Yamazaki, Takumi*; Hirai, Takamasa*; Yagi, Takashi*; Yamashita, Yuichiro*; Uchida, Kenichi*; Seki, Takeshi*; Takanashi, Koki
Physical Review Applied (Internet), 21(2), p.024039_1 - 024039_11, 2024/02
Times Cited Count:2 Percentile:82.37(Physics, Applied)Fukuda, Tatsuo; Kobata, Masaaki; Shobu, Takahisa; Yoshii, Kenji; Kamiya, Junichiro; Iwamoto, Yosuke; Makino, Takahiro*; Yamazaki, Yuichi*; Oshima, Takeshi*; Shirai, Yasuhiro*; et al.
Journal of Applied Physics, 132(24), p.245102_1 - 245102_8, 2022/12
Times Cited Count:1 Percentile:9.28(Physics, Applied)Direct energy conversion has been investigated using Ni/SiC Schottky junctions with the irradiation of monochromatized synchrotron X-rays simulating the gamma rays of Np (30 keV) and Am (60 keV). From current-voltage measurements, electrical energies were obtained for both kinds of gamma rays. The energy conversion efficiencies were found to reach up to 1.6%, which is comparable to those of a few other semiconducting systems reported thus far. This result shows a possibility of energy recovery from nuclear wastes using the present system, judging from the radiation tolerant nature of SiC. Also, we found different conversion efficiencies between the two samples. This could be understandable from hard X-ray photoelectron spectroscopy and secondary ion mass spectroscopy measurements, suggesting the formation of Ni-Si compounds at the interface in the sample with a poor performance. Hence, such combined measurements are useful to provide information that cannot be obtained by electrical measurements alone.
Yamamoto, Kazami; Kinsho, Michikazu; Hayashi, Naoki; Saha, P. K.; Tamura, Fumihiko; Yamamoto, Masanobu; Tani, Norio; Takayanagi, Tomohiro; Kamiya, Junichiro; Shobuda, Yoshihiro; et al.
Journal of Nuclear Science and Technology, 59(9), p.1174 - 1205, 2022/09
Times Cited Count:7 Percentile:80.72(Nuclear Science & Technology)In the Japan Proton Accelerator Research Complex, the purpose of the 3 GeV rapid cycling synchrotron (RCS) is to accelerate a 1 MW, high-intensity proton beam. To achieve beam operation at a repetition rate of 25 Hz at high intensities, the RCS was elaborately designed. After starting the RCS operation, we carefully verified the validity of its design and made certain improvements to establish a reliable operation at higher power as possible. Consequently, we demonstrated beam operation at a high power, namely, 1 MW. We then summarized the design, actual performance, and improvements of the RCS to achieve a 1 MW beam.
Sasaki, Hirokazu*; Nishikubo, Hideo*; Nishida, Shinsuke*; Yamazaki, Satoshi*; Nakasaki, Ryusuke*; Isomatsu, Takemi*; Minato, Ryuichiro*; Kinugawa, Kohei*; Imamura, Akihiro*; Otomo, Shinya*; et al.
Furukawa Denko Jiho, (138), p.2 - 10, 2019/02
no abstracts in English
Oguri, Hidetomo; Hasegawa, Kazuo; Ito, Takashi; Chishiro, Etsuji; Hirano, Koichiro; Morishita, Takatoshi; Shinozaki, Shinichi; Ao, Hiroyuki; Okoshi, Kiyonori; Kondo, Yasuhiro; et al.
Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.389 - 393, 2014/10
no abstracts in English
Osamura, Kozo*; Machiya, Shutaro*; Hampshire, D. P.*; Tsuchiya, Yoshinori*; Shobu, Takahisa; Kajiwara, Kentaro*; Osabe, Goro*; Yamazaki, Kohei*; Yamada, Yuichi*; Fujikami, Jun*
Superconductor Science and Technology, 27(8), p.085005_1 - 085005_11, 2014/08
Times Cited Count:29 Percentile:73.19(Physics, Applied)Fujioka, Jun*; Yasue, Toshio*; Miyasaka, Shigeki*; Yamazaki, Yuichi*; Arima, Takahisa*; Sagayama, Hajime*; Inami, Toshiya; Ishii, Kenji; Tokura, Yoshinori*
Physical Review B, 82(14), p.144425_1 - 144425_12, 2010/10
Times Cited Count:54 Percentile:85.54(Materials Science, Multidisciplinary)Kajimoto, Ryoichi; Sagayama, Hajime*; Sasai, Kenzo*; Fukuda, Tatsuo; Tsutsui, Satoshi*; Arima, Takahisa*; Hirota, Kazuma*; Mitsui, Yukari*; Yoshizawa, Hideki*; Baron, A. Q. R.*; et al.
Physical Review Letters, 102(24), p.247602_1 - 247602_4, 2009/06
Times Cited Count:12 Percentile:58.34(Physics, Multidisciplinary)Arima, Takahisa*; Goto, Tsuyoshi*; Yamazaki, Yuichi*; Miyasaka, Shigeki*; Ishii, Kenji; Tsubota, Masami; Inami, Toshiya; Murakami, Yoichi*; Tokura, Yoshinori*
Physical Review B, 72(10), p.100102_1 - 100102_4, 2005/09
Times Cited Count:132 Percentile:95.47(Materials Science, Multidisciplinary)Single-crystal synchrotron X-ray diffraction measurements in strong magnetic fields have been performed for magnetoelectric compounds GdMnO and TbMnO. It has been found that the //a ferroelectric phase induced by the application of a magnetic field at low temperatures is characterized by commensurate lattice modulation along the orthorhombic axis with q=1/2 and q=1/4. The lattice modulation is ascribed to antiferromagnetic spin alignment with a modulation vector of (0 1/4 1). The change of the spin structure is directly correlated with the magnetic-field-induced electric phase transition, because any commensurate spin modulation with (0 1/4 1) should break glide planes normal to the axis of the distorted perovskite with the space group.
Tajima, Taiyo*; Asai, Shiho*; Saito, Kyoichi*; Seko, Noriaki*; Hoshina, Hiroyuki*; Horita, Takuma; Yamazaki, Shinya*; Takaku, Yuichi*; Sueki, Keisuke*; Sakaguchi, Aya*
no journal, ,
Cs is a radionuclide introduced into the environment by human nuclear activities. The use of Cs as an oceanic circulation tracer and the need for monitoring around nuclear facilities require the establishment of a measurement method for this nuclide. In this study, the appropriate adsorption and desorption conditions of Cs in seawater using the insoluble cobalt ferrocyanide-impregnated adsorbent synthesized by graft polymerisation were investigated. A chemical separation method of Cs for mass spectrometry was also investigated.
Kajimoto, Ryoichi; Sagayama, Hajime*; Sasai, Kenzo*; Fukuda, Tatsuo; Tsutsui, Satoshi*; Arima, Takahisa*; Hirota, Kazuma*; Mitsui, Yukari*; Yoshizawa, Hideki*; Baron, A. Q. R.*; et al.
no journal, ,
Yoshii, Kenji; Fukuda, Tatsuo; Kamiya, Junichiro; Shiwaku, Hideaki; Kobayashi, Toru; Tanida, Hajime; Yamazaki, Yuichi*; Oshima, Takeshi*; Yaita, Tsuyoshi
no journal, ,
Management of radioactive wastes is one of the main issues of nuclear power technology. Radioactive wastes can be regarded as energy resources because of their stable radioactive emissions for long half-lives. In this study, we have attempted a direct conversion from gamma rays to electricity using solid state materials such as III-V semiconductors. The experiments were done using the gamma rays of 660keV (Cs), 60 keV (Am), 30 keV (Np). The energy conversion efficiencies were 0.1-1%. Details will be reported at the conference.
Yoshii, Kenji; Fukuda, Tatsuo; Tanida, Hajime; Shiwaku, Hideaki; Kamiya, Junichiro; Makino, Takahiro*; Yamazaki, Yuichi*; Oshima, Takeshi*; Yaita, Tsuyoshi
no journal, ,
We have carried out direct energy conversion from gamma rays to electricity using SiC free of toxic elements. The experiments were done using synchrotron radiation at the BL22XU beamline. To utilize radioactive wastes as an energy source, the gamma ray energies were 30 and 60 keV, corresponding to the energies from Np and Am, respectively. Also, CuK X-rays were used to show a possibility of micro batteries using radioisotopes. The samples were Ni/SiC Schottky barrier junctions. From dark current experiments, it was found that the samples were regarded as ideal diodes on the basis of the so-called ideality factors. The electric powers under gamma rays and X-rays were found to be about 0.1W, corresponding to efficiencies less than 0.1%. We will also show the results of energy depositions on the basis of Monte Carlo methods.
Fukuda, Tatsuo; Kobata, Masaaki; Shobu, Takahisa; Yoshii, Kenji; Kamiya, Junichiro; Iwamoto, Yosuke; Makino, Takahiro*; Yamazaki, Yuichi*; Oshima, Takeshi*; Shirai, Yasuhiro*; et al.
no journal, ,
no abstracts in English