Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Fujiwara, Hidenori*; Umetsu, Rie*; Kuroda, Fumiaki*; Miyawaki, Jun*; Kashiuchi, Toshiyuki*; Nishimoto, Kohei*; Nagai, Kodai*; Sekiyama, Akira*; Irizawa, Akinori*; Takeda, Yukiharu; et al.
Scientific Reports (Internet), 11(1), p.18654_1 - 18654_9, 2021/09
Times Cited Count:0 Percentile:0(Multidisciplinary Sciences)Ishibashi, Masayuki; Ando, Tomomi*; Sasao, Eiji; Yuguchi, Takashi; Nishimoto, Shoji*; Yoshida, Hidekazu*
Oyo Chishitsu, 55(4), p.156 - 165, 2014/10
Understanding of long-term history of water-conducting features such as flow-path fractures is key issue to evaluate deep geological environment for geological disposal of high-level radioactive waste (HLW). Thus, we conducted study on the geological features and the long-term behavior of flow-path fractures based on the data obtained at -300m levels in the Mizunami Underground research laboratory (MIU), central Japan. Total 1670 fractures were mapped in underground gallery at the -300m levels. Flow-path fractures occupy about 11% of all fractures. The flow-path fractures are divided into grout filling fractures and low inflow-rate fractures. All of the grout filling fractures is filled with calcite as fracture filling minerals without conspicuous host rock alteration around fractures. The low inflow-rate fractures possessed similar geological character with the sealed fractures which are not acted as flow-path. The geological character of fracture filling and host tock alteration around fractures indicates the history of the formation at the time of intrusion and emplacement of host granite (Stage I), then filling at hydrothermal event (Stage II), and finally opening and elongation during exhumation stage (Stage III). In conclusion, the present flow-path fractures were formed by opening and/or elongation of pre-existed fractures, which were filled at the hydrothermal event, at the time of exhumation.
Tanigawa, Hiroyasu; Hirose, Takanori; Shiba, Kiyoyuki; Kasada, Ryuta*; Wakai, Eiichi; Serizawa, Hisashi*; Kawahito, Yosuke*; Jitsukawa, Shiro; Kimura, Akihiko*; Kono, Yutaka*; et al.
Fusion Engineering and Design, 83(10-12), p.1471 - 1476, 2008/12
Times Cited Count:78 Percentile:97.72(Nuclear Science & Technology)Reduced activation ferritic/martensitic steels (RAFMs) are recognized as the primary candidate structural materials for fusion blanket systems. F82H, which were developed and studied in Japan, was designed with an emphasis on high temperature properties and weldability. The database on F82H properties is currently the most extensive available among the existing RAFMs. The objective of this paper is to review the R&D status of F82H and to identify the key technical issues for the fabrication of an ITER Test Blanket Module (TBM) suggested by recent achievements in Japan.
Tanigawa, Hiroyasu; Ogiwara, Hiroyuki; Hirose, Takanori; Shiba, Kiyoyuki; Serizawa, Hisashi*; Kawahito, Yosuke*; Tanaka, Manabu*; Katayama, Seiji*; Mori, Hiroaki*; Nishimoto, Kazutoshi*
no journal, ,
Reduced activation ferritic/martensitic steels (RAFMs) are recognized as the primary candidate structural materials for fusion blanket systems. These steels have been developed based on substantial industrial experience with high chromium heat resistant ferritic/martensitic steels (such as modified 9Cr-1Mo), but with Mo and Nb replaced by W and Ta, respectively. The objective of this paper is to review the R&D status of F82H and to identify the key technical issues for the fabrication of an ITER Test Blanket Module (TBM) suggested by recent achievements in Japan.
Ishibashi, Masayuki; Tsuruta, Tadahiko; Yuguchi, Takashi; Nishimoto, Shoji*; Sasao, Eiji; Yoshida, Hidekazu*
no journal, ,
no abstracts in English
Hirose, Takanori; Shirai, Yuma*; Ogiwara, Hiroyuki*; Mori, Hiroaki*; Serizawa, Hisashi*; Saida, Kazuyuki*; Nishimoto, Kazutoshi*; Tanigawa, Hiroyasu
no journal, ,
no abstracts in English
Nishimoto, Yuki*; Horie, Hiroki*; Akiyama, Yoko*; Nishijima, Shigehiro*; Mitsui, Seiichiro; Umezawa, Katsuhiro; Kato, Mitsugu; Okada, Takashi; Sekiyama, Tomio*
no journal, ,
By the accident of Fukushima Daiichi Nuclear Power Plant, a large amount of soil was contaminated by radioactive cesium. We developed a new physical treatment method using magnetic separation that can separate high-dose 2:1 type clay minerals from contaminated soil selectively. However, there is an issue that it is difficult to capture 2:1 type clay minerals efficiently, because clay minerals form aggregations with soil organic matter. Our previous study indicated that aggregates can be dispersed effectively by treatment of organic matter with KCO solution. The purpose of this study is to assess the effect of the organic matter treatment on efficiency improvement of magnetic separation for 2:1 type clay minerals. The result showed that the possibility of effective treatment method for the soil rich in organic matter like agricultural soil by combination of the pretreatment with KCO solution and magnetic separation.