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Kataoka, Takahiro*; Shuto, Hina*; Naoe, Shota*; Yano, Junki*; Kanzaki, Norie; Sakoda, Akihiro; Tanaka, Hiroshi; Hanamoto, Katsumi*; Mitsunobu, Fumihiro*; Terato, Hiroaki*; et al.
Journal of Radiation Research (Internet), 62(5), p.861 - 867, 2021/09
Times Cited Count:5 Percentile:40.41(Biology)Kataoka, Takahiro*; Kanzaki, Norie; Sakoda, Akihiro; Shuto, Hina*; Yano, Junki*; Naoe, Shota*; Tanaka, Hiroshi; Hanamoto, Katsumi*; Terato, Hiroaki*; Mitsunobu, Fumihiro*; et al.
Journal of Radiation Research (Internet), 62(2), p.206 - 216, 2021/03
Times Cited Count:7 Percentile:52.03(Biology)Radon inhalation activates antioxidative functions in mouse organs, thereby contributing to inhibition of oxidative stress-induced damage. Therefore, in this study, we evaluated the redox state of various organs in mice following radon inhalation. Mice inhaled radon at concentrations of 2 or 20 kBq/m for 1, 3, or 10 days. The relationship between antioxidative function and oxidative stress was evaluated by principal component analysis (PCA) and correlation coefficient compared with control mice subjected to sham inhalation. These findings suggested that radon inhalation altered the redox state in organs, but that the characteristics varied depending on the redox state in organs.
Yasuda, Satoshi; Uchibori, Yosuke*; Wakeshima, Makoto*; Hinatsu, Yukio*; Ogawa, Hiroaki; Yano, Masahiro; Asaoka, Hidehito
RSC Advances (Internet), 8(66), p.37600 - 37605, 2018/11
Times Cited Count:13 Percentile:40.30(Chemistry, Multidisciplinary)We present a quantitative study on the effect of a newly obtained thermal history on the formation of Fe-N-C catalytic sites. A short and repeated heating process is employed as the new thermal history, where short heating (1 min) followed by quenching is applied to a sample with arbitrary repetition. Through electrochemical quantitative analysis, it is found that the new process effectively increases the Fe-N-C mass-based site density (MSD) to almost twice that achieved using a conventional continuous heating process, while the turn-over frequency (TOF) is independent of the process. Elemental analysis shows that the new process effectively suppresses the thermal desorption of Fe and N atoms during the initial formation stage and consequently contributes to an increase in the Fe-N-C site density. The resultant catalytic activity (gravimetric kinetic current density (0.8 V vs. RHE)) is 1.8 times higher than that achieved with the continuous heating process.
Sato, Toshinori; Sasamoto, Hiroshi; Ishii, Eiichi; Matsuoka, Toshiyuki; Hayano, Akira; Miyakawa, Kazuya; Fujita, Tomoo*; Tanai, Kenji; Nakayama, Masashi; Takeda, Masaki; et al.
JAEA-Research 2016-025, 313 Pages, 2017/03
The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. This report summarizes the results of the Phase II investigations carried out from April 2005 to June 2014 to a depth of 350m. Integration of work from different disciplines into a "geosynthesis" ensures that the Phase II goals have been successfully achieved and identifies key issues that need to made to be addressed in the Phase II investigations Efforts are made to summarize as many lessons learnt from the Phase II investigations and other technical achievements as possible to form a "knowledge base" that will reinforce the technical basis for both implementation and the formulation of safety regulations.
Cai, L.*; Hirao, Toshio; Yano, Hiroaki*; Duan, Z.*; Takayanagi, Yutaro*; Ueki, Hideharu*; Oshima, Takeshi; Nishioka, Yasushiro*
Materials Science Forum, 687, p.576 - 579, 2011/06
Times Cited Count:4 Percentile:86.04(Engineering, Electrical & Electronic)no abstracts in English
Kunimaru, Takanori; Mikake, Shinichiro; Nishio, Kazuhisa; Tsuruta, Tadahiko; Matsuoka, Toshiyuki; Hayano, Akira; Takeuchi, Ryuji; Saegusa, Hiromitsu; Oyama, Takuya; Mizuno, Takashi; et al.
JAEA-Review 2011-007, 145 Pages, 2011/03
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). Geoscientific research and the MIU Project are planned in three overlapping phases; Surface-based Investigation Phase (Phase 1), Construction Phase (Phase 2) and Operation Phase (Phase 3). Currently, the project is under the Construction Phase. This document introduces the results of the research and development in fiscal year 2009, as a part of the Construction Phase based on the MIU Master Plan updated in 2002, (1) Investigation at the MIU Construction Site and the Shobasama Site, (2) Construction at the MIU Construction Site, (3) Research Collaboration, etc. The goals of the Phase 2 are to develop and revise the models of the geological environment using the investigation results obtained during excavation and determine and assess changes in the geological environment in response to excavation, to evaluate the effectiveness of engineering techniques used for construction, maintenance and management of underground facilities, to establish detailed investigation plans of Phase 3.
Cai, L.*; Hirao, Toshio; Yano, Hiroaki*; Duan, Z.*; Takayanagi, Hideharu*; Ueki, Hideharu*; Oshima, Takeshi; Nishioka, Yasushiro*
Proceedings of 9th International Workshop on Radiation Effects on Semiconductor Devices for Space Applications (RASEDA-9), p.176 - 178, 2010/10
no abstracts in English
Takeuchi, Shinji; Kunimaru, Takanori; Mikake, Shinichiro; Nishio, Kazuhisa; Tsuruta, Tadahiko; Matsuoka, Toshiyuki; Hayano, Akira; Takeuchi, Ryuji; Saegusa, Hiromitsu; Oyama, Takuya; et al.
JAEA-Review 2010-029, 28 Pages, 2010/08
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). Geoscientific research and the MIU project is planned in three overlapping phases; Surface-based investigation phase (Phase1), Construction phase (Phase2) and Operation phase (Phase3). The project is currently under the construction phase, and the operation phase starts in 2010. This document introduces the research and development activities planned for 2010 fiscal year plan based on the MIU master plan updated in 2010, (1) Investigation plan, (2) Construction plan, (3) Research collaboration plan, etc.
Takeuchi, Shinji; Kunimaru, Takanori; Mikake, Shinichiro; Nishio, Kazuhisa; Tsuruta, Tadahiko; Matsuoka, Toshiyuki; Hayano, Akira; Takeuchi, Ryuji; Saegusa, Hiromitsu; Oyama, Takuya; et al.
JAEA-Review 2010-014, 110 Pages, 2010/07
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is developing a geoscientific research project named Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to establish scientific and technological basis for geological disposal of HLW. Geoscientific research at MIU is planned to be carried out in three phases over a period of 20 years; Surface-based Investigation Phase (Phase I), Construction Phase (Phase II) and Operation Phase (Phase III). Currently, the project is under the Construction Phase. This document presents the following results of the research and development performed in fiscal year 2008, as a part of the Construction Phase based on the MIU Master Plan updated in 2002, (1) Investigation at the MIU Construction Site and the Shobasama Site, (2) Construction at the MIU Construction Site, (3) Research Collaboration.
Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05
Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.
Takeuchi, Shinji; Mikake, Shinichiro; Nishio, Kazuhisa; Tsuruta, Tadahiko; Amano, Kenji; Matsuoka, Toshiyuki; Hayano, Akira; Takeuchi, Ryuji; Saegusa, Hiromitsu; Oyama, Takuya; et al.
JAEA-Review 2009-017, 29 Pages, 2009/08
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is developing a geoscientific research project named the Mizunami Underground Research Laboratory (MIU) project in crystalline rock environment in order to establish scientific and technological basis for geological disposal of HLW. Geoscientific research at the MIU project is planned to be carried out in three phases over a period of 20 years; Surface-based Investigation Phase (Phase 1), Construction Phase (Phase 2) and Operation Phase (Phase 3). Currently, the project is under the Construction Phase. This document presents the following 2009 fiscal year plan based on the MIU Master Plan updated in 2002, (1) Investigation Plan, (2) Construction Plan, (3) Research Collaboration Plan, etc.
Michizono, Shinichiro*; Anami, Shozo*; Katagiri, Hiroaki*; Fang, Z.*; Matsumoto, Toshihiro*; Miura, Takako*; Yano, Yoshiharu*; Yamaguchi, Seiya*; Kobayashi, Tetsuya
Kasokuki, 5(2), p.127 - 136, 2008/07
One of the biggest advantages of the digital low level rf (LLRF) system is its flexibility. Owing to the recent rapid progress in digital devices (such as ADCs and DACs) and telecommunication devices (mixers and IQ modulators), digital LLRF system for accelerators becomes popular in these 10 years. The J-PARC linac LLRF system adopted cPCI crates and FPGA based digital feedback system. After the successful operation of J-PARC linac LLRF system, we developed the STF (ILC test facility in KEK) LLRF system. The future R&D projects (ILC and ERL) are also described from the viewpoints of LLRF.
Kuwabara, K.*; Kurishita, Hiroaki*; Ukai, Shigeharu; Narui, Makoto*; Mizuta, Shunji; Yamazaki, M.*; Kayano, H.*
Journal of Nuclear Materials, 258-263(Part 2), p.1236 - 1241, 1998/10
Times Cited Count:29 Percentile:88.09(Materials Science, Multidisciplinary)None
Kataoka, Takahiro*; Kanzaki, Norie; Sakoda, Akihiro; Shuto, Hina*; Yano, Junki*; Ishida, Tsuyoshi*; Tanaka, Hiroshi; Hanamoto, Katsumi*; Terato, Hiroaki*; Mitsunobu, Fumihiro*; et al.
no journal, ,
no abstracts in English
Sato, Naomi; Murakami, Hiroaki; Aoyagi, Kazuhei; Tamura, Tomonori; Hayano, Akira
no journal, ,
Faults and fractures with high permeability and areas where faults and fractures decrease rock mechanical strength are undesirable for the emplacement of disposal tunnels and pits/holes in geological repositories. Thus, it is important to predict key geological characteristics such as the distribution of faults/fissures, groundwater inflow and excavation damage zones (EDZ) for locating disposal tunnels and pits/holes. This presentation will introduce the predictive analysis of fractures, hydraulic properties, and hydraulic conductivity of the Excavation Damaged Zone (EDZ) before excavation of the Experimental Gallery at 500 m depth of Horonobe URL as part of the Horonobe International Project (HIP).
Sayano, Akio*; Kano, Fumihisa*; Saito, Norihisa*; Abe, Hiroaki*; Okamoto, Koji*; Takamasa, Tomoji*; Furuya, Masahiro*; Miyano, Masami*; Yoshikawa, Masahito
no journal, ,
no abstracts in English
Yano, Kimihiko; Kaji, Naoya; Washiya, Tadahiro; Saiki, Yohei*; Kakiuchi, Kazuo*; Kanaoka, Takuya*; Muta, Hiroaki*; Yamanaka, Shinsuke*
no journal, ,
no abstracts in English
Ikeuchi, Hirotomo; Yano, Kimihiko; Ogino, Hideki; Saiki, Yohei*; Honda, Masaki*; Kinoshita, Hideaki*; Muta, Hiroaki*; Yamanaka, Shinsuke*
no journal, ,
In the case of Fukushima Daiichi Nuclear Power Station (1F) Accident, it is estimated that the fuel assemblies were damaged seriously and that fuel deburis deposits in the core or the bottom of vessel. The methodology of defueling such as cutting and core boring is considered referring the case of Three Mile Island Unit 2 (TMI-2) Accident. It is supposed that fuel debris have various characteristics depending on the location. Especially, the information on mechanical properties of fuel debris is important in order to select and develop the defueling technologies. In this work, (U,Zr)O as simulated debris including Y
O
, CeO
, CaO, which exist as a fisson product or a component of concrete and behavior as stabilizer for ZrO
, was prepared and their mechanical properties were evaluated.
Tanno, Takashi; Oka, Hiroshi; Yano, Yasuhide; Kurishita, Hiroaki*
no journal, ,
Fracture toughness is an important property when ferritic martensitic steel (FMS) is irradiated and thermally aged. The goal of this study is to develop reasonably miniaturized fracture toughness test technique which can be applied for irradiated or sampled from welded small specimen. In this phase, the capability of miniature 3-point bend (3PB) test technique for evaluating toughness, and the side groove effect on miniatured specimen were confirmed. A miniature 3PB type J test conforming to ASTM 1820 was applied to the PNC-FMS developed for the fast reactor. The effect of the root radius of the side groove that controls the crack propagation was verified for the specimen miniaturized to 5 mm thickness, 3 mm width and 22.5 mm length according to the thickness of the wrapper tube. The crack winded and/or branched with root radius of 0.5 mm, the standard size of ASTM1820. But by making it 0.05 mm, it was possible to control the crack propagation along the side groove. As a result, J = 300 kJ/m
was obtained, and a prospect of this technique was obtained for the fracture toughness evaluation of the wrapper tube by improving the side groove.
Tanno, Takashi; Yano, Yasuhide; Oka, Hiroshi*; Kurishita, Hiroaki*
no journal, ,
Miniature 3 point bend test was applied to evaluate fracture toughness of ferritic/martensitic steel (PNC-FMS) for fast reactor subassembly wrapper tube. In this work, it was clarified that pre-crack length and open angle of side groove are important to obtain the certain and conservative fracture toughness with miniatured specimen. Finally, the fracture toughness value J of PNC-FMS could be obtained with miniaturized specimen which can be applied to wrapper tube thickness.