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Yan, X.; Sato, Hiroyuki; Sumita, Junya; Nomoto, Yasunobu*; Horii, Shoichi*; Imai, Yoshiyuki; Kasahara, Seiji; Suzuki, Koichi*; Iwatsuki, Jin; Terada, Atsuhiko; et al.
Nuclear Engineering and Design, 329, p.223 - 233, 2018/04
Times Cited Count:28 Percentile:92.01(Nuclear Science & Technology)The pre-licensing design of an HTGR cogeneration test plant to be coupled to JAEA's existing test reactor HTTR is presented. The plant is designed to demonstrate the system of JAEA commercial plant design GTHTR300C. With construction planned to be completed around 2025, the test plant is expected to be the first-of-a-kind nuclear system operating on two of the advanced energy conversion systems attractive for the HTGR closed cycle helium gas turbine for power generation and thermochemical iodine-sulfur water-splitting process for hydrogen production.
Yan, X.; Sato, Hiroyuki; Sumita, Junya; Nomoto, Yasunobu; Horii, Shoichi; Imai, Yoshiyuki; Kasahara, Seiji; Suzuki, Koichi*; Iwatsuki, Jin; Terada, Atsuhiko; et al.
Proceedings of 8th International Topical Meeting on High Temperature Reactor Technology (HTR 2016) (CD-ROM), p.827 - 836, 2016/11
Pre-licensing basic design for a cogenerating HTGR test plant system is presented. The plant to be coupled to existing 30 MWt 950C test reactor HTTR is intended as a system technology demonstrator for GTHTR300C plant design. More specifically the test plant of HTTR-GT/H
aims to (1)demonstrate the licensability of the GTHTR300C for electricity production by gas turbine and hydrogen cogeneration by thermochemical process and (2) confirm the operation control and safety of such cogeneration system. With construction and operation completion by 2025, the test plant is expected to be the first of a kind HTGR-powered cogeneration plant operating on the two advanced energy conversion systems of closed cycle helium gas turbine for power generation and thermochemical iodine-sulfur water-splitting process for hydrogen production.
Sato, Satoshi; Maegawa, Toshio*; Yoshimatsu, Kenji*; Sato, Koichi*; Nonaka, Akira*; Takakura, Kosuke; Ochiai, Kentaro; Konno, Chikara
Progress in Nuclear Science and Technology (Internet), 4, p.623 - 626, 2014/04
In the previous study, we developed a multi-layered concrete structure to reduce induced activity in concrete applied for neutron generation facilities such as a fusion reactor. This structure is composed of low activation concrete as the first layer, boron doped low activation concrete as the second layer and ordinary concrete as the third layer from the side of the neutron source. In this study, as an alternative of the boron doped low activation concrete we have developed the boron doped resin sheet with boron carbonate and resin to reduce the construction cost. The weight ratio of the boron carbonate to the resin is 0.75. The developed boron sheet has good flexibility and sufficient strength for repeated bending. DT neutron irradiation experiments for four multi-layered concrete structures with the boron sheet have been performed at the FNS (Fusion Neutronics Source) facility in JAEA in order to study shielding performance of the structures with the boron sheet. Structure-1 of about 30 cm in width, 30 cm in height and 50 cm in thickness is composed of low activation concrete of 20 cm in thickness as the first layer and ordinary concrete of 30 cm in thickness as the second layer. The boron sheet is inserted between the first and second layers. In Structure-2 one more boron sheet is inserted at the 10 cm depth from the surface of Structure-1. Structure-3 added one more boron sheet at 30 cm depth from the surface of Strucure-2. For comparison, Structure-4 has no boron sheet. The reaction rates were measured every 5 cm in depth with activation foils of gold and niobium. By inserting the boron sheet, the reaction rate of the gold generated by low energy neutrons decreases by a factor of about four. It is demonstrated that the multi-layered concrete structure with the boron sheet effectively reduces low energy neutrons.
Sato, Satoshi; Maegawa, Toshio*; Yoshimatsu, Kenji*; Sato, Koichi*; Nonaka, Akira*; Takakura, Kosuke; Ochiai, Kentaro; Konno, Chikara
Journal of Nuclear Materials, 417(1-3), p.1131 - 1134, 2011/10
Times Cited Count:11 Percentile:61.29(Materials Science, Multidisciplinary)The multi-layered concrete structure has been developed to reduce induced activity in the concrete applied for neutron generation facilities such as a fusion reactor. The multi-layered concrete structure is composed of the low activation concrete as the first layer, the boron-doped low activation concrete as the second layer and the ordinary concrete as the third layer from the side of the neutron source. By applying the multi-layered concrete structure, the volume of the boron can drastically decrease compared with the monolithic boron-doped concrete. A 14 MeV neutron irradiation experiment with the multi-layered concrete structure mockups was performed at FNS and several reaction rates and induced activities in the mockups were measured. This experiment demonstrated that the multi-layered concrete effectively reduced low energy neutrons and induced activities.
Maegawa, Toshio*; Umetsu, Tomotake*; Nonaka, Akira*; Yoshimatsu, Kenji*; Sato, Koichi*; Sato, Satoshi; Nishitani, Takeo
Semento, Konkurito, (719), p.26 - 31, 2007/01
no abstracts in English
Suzuki, Junichi; Oku, Takayuki; Adachi, Tomohiro*; Shimizu, Hirohiko; Kiyanagi, Yoshiaki*; Kamiyama, Takashi*; Hiraga, Fujio*; Iwasa, Hirokatsu*; Sato, Koichi*; Furusaka, Michihiro*
Nuclear Instruments and Methods in Physics Research A, 529(1-3), p.120 - 124, 2004/08
Times Cited Count:11 Percentile:57.39(Instruments & Instrumentation)no abstracts in English
Nagai, Takayuki; Kobayashi, Hidekazu; Sasage, Kenichi; Oyama, Koichi; Sato, Seiichi*; Inose, Takehiko*; Hatakeyama, Kiyoshi*
no journal, ,
We estimated the long chemical stability of simulated waste borosilicate glass samples reacting with water in a closed case by the immersion test in alkaline solution and confirmed the effect which restrains the elution of molybdenum to the solution from the glass samples made with the frit including phosphorus. After cooling the simulated waste glass samples from melt condition, the crystallization behavior in the glass samples made with the frit including phosphorus was confirmed similar to that of the sample made with a present frit composition.
Kira, Hiroshi; Sakaguchi, Yoshifumi; Oku, Takayuki; Suzuki, Junichi; Nakamura, Mitsutaka; Arai, Masatoshi; Endo, Yasuo; Kakurai, Kazuhisa; Arimoto, Yasushi*; Ino, Takashi*; et al.
no journal, ,
no abstracts in English
Shinohara, Takenao; Suzuki, Junichi; Oku, Takayuki; Iwashita, Hidenori*; Kamiyama, Takashi*; Iwasa, Hirokatsu*; Hiraga, Fujio*; Kiyanagi, Yoshiaki*; Sato, Koichi*; Shimizu, Hirohiko*
no journal, ,
no abstracts in English
Maegawa, Toshio*; Sato, Satoshi; Yoshimatsu, Kenji*; Sato, Koichi*; Nonaka, Akira*; Takakura, Kosuke; Ochiai, Kentaro; Konno, Chikara
no journal, ,
no abstracts in English
Shinohara, Takenao; Suzuki, Junichi; Oku, Takayuki; Iwashita, Hidenori*; Kamiyama, Takashi*; Iwasa, Hirokatsu*; Hiraga, Fujio*; Kiyanagi, Yoshiaki*; Sato, Koichi*; Shimizu, Hirohiko*
no journal, ,
no abstracts in English
Sato, Satoshi; Maegawa, Toshio*; Yoshimatsu, Kenji*; Sato, Koichi*; Nonaka, Akira*; Takakura, Kosuke; Ochiai, Kentaro; Konno, Chikara
no journal, ,
no abstracts in English
Nagai, Takayuki; Inose, Takehiko*; Sato, Seiichi*; Nishizawa, Daiji; Oyama, Koichi; Kobayashi, Hidekazu; Yamashita, Teruo; Amamoto, Ippei
no journal, ,
Raman spectrometry was performed for the borosilicate glass samples which added alkali oxides or rare-earth oxides, and the influence of the Raman spectrum of the glass sample by addition of their oxides was evaluated.
Nagai, Takayuki; Nishizawa, Daiji; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*; Seki, Katsumi*; Oyama, Koichi; Kano, Shigeru
no journal, ,
no abstracts in English
Nagai, Takayuki; Sasage, Kenichi; Oyama, Koichi; Sato, Nobuaki*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*
no journal, ,
no abstracts in English
Nagai, Takayuki; Sasage, Kenichi; Oyama, Koichi; Sato, Nobuaki*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*
no journal, ,
no abstracts in English
Nagai, Takayuki; Sasage, Kenichi; Oyama, Koichi; Sato, Nobuaki*; Inose, Takehiko*; Sato, Seiichi*; Hatakeyama, Kiyoshi*
no journal, ,
no abstracts in English
Okamoto, Yoshihiro; Nagai, Takayuki; Kobayashi, Hidekazu; Oyama, Koichi; Sasage, Kenichi; Shiwaku, Hideaki; Inose, Takehiko*; Sato, Seiichi*
no journal, ,
The local structures around some elements in newly developed nuclear waste glass simulation samples using phosphorus-doped borosilicate glass and iron phosphate glass as frit were investigated by synchrotron radiation based XAFS analysis. It was found that the addition of phosphorus to borosilicate glass changes the glass to a significant reduction state and counteract oxidation effects induced by increasing waste loading. In iron phosphate glass with a composition of 30% FeO
-P
O
, the XAFS analysis results showed that the solubility of ruthenium could reach 0.5-1.0%.
Yoshida, Hidekazu*; Yamamoto, Koshi*; Maruyama, Ippei*; Karukaya, Koichi*; Nakayama, Masashi; Sakurai, Akitaka; Sato, Toshinori
no journal, ,
Spherical, isolated carbonate concretions occur throughout the world in marine argillaceous sedimentary rocks of widely varying geological ages. These concretions are characteristically highly enriched in CaCO compared to the surrounding sedimentary rock matrices and are commonly containing the well-preserved fossils inside. Recently the process of the enrichment of CaCO
has been revealed and synthetic concretion materials are developed. Here we will introduce the in-situ experiment with the synthetic concretion material for EDZ sealing carried out in Horonobe Underground Research Laboratory and the preliminary results of the EDZ sealing process and their sealing effectiveness.
Nonaka, Akira*; Yoshimatsu, Kenji*; Sato, Koichi*; Maegawa, Toshio*; Sasaki, Shizuo*; Umetsu, Tomotake*; Sato, Satoshi
no journal, ,
no abstracts in English