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Hirayama, Ryoichi*; Uzawa, Akiko*; Takase, Nobuhiro*; Matsumoto, Yoshitaka*; Noguchi, Miho; Koda, Kana*; Ozaki, Masakuni*; Yamashita, Kei*; Li, H.*; Kase, Yuki*; et al.
Mutation Research; Genetic Toxicology And Environmental Mutagenesis, 756(1-2), p.146 - 151, 2013/08
Times Cited Count：24 Percentile：62.77(Biotechnology & Applied Microbiology)Noguchi, Akira; Kishi, Hirokazu; Hatanaka, Koichiro; Naito, Morimasa
Proceedings of 19th International Conference on Nuclear Engineering (ICONE-19) (CD-ROM), 6 Pages, 2011/10
A standardized method for choosing a mix design of low pH shotcrete is proposed for their intended use in the construction of a High Level Radioactive Waste (HLW) repository in order to be applied to the various geological environment of the location of the HLW repositories. There are two improvement in this method. One is estimating binder composition to satisfy low pH. The other is estimating water bender ratio to satisfy the strength of sprayed concrete. The method uses a sequential development process with consideration given to a number of physicochemical requirements, incorporates current shotcrete technology. The method is demonstrated in its entirety through a series of experiments and tests using a low pH cement binder comprised of a mixture of ordinary Portland cement, fly ash (FA) and silica fume (SF), referred to here as high-volume FA SF cement (HFSC). Moreover, the method is referred from the demonstration of HFSC shotcrete in Horonobe underground research laboratory.
Ito, Hideaki; Maeda, Shigetaka; Naito, Hiroyuki; Akiyama, Yoichi; Miyamoto, Kazuyuki; Ashida, Takashi; Noguchi, Koichi; Ito, Chikara; Aoyama, Takafumi
JAEA-Technology 2010-049, 129 Pages, 2011/03
JAEA-Technology-2010-049.pdf:6.99MB
The in-vessel gamma dose rate was measured in the experimental fast reactor Joyo to evaluate the activation of reactor structural components and the radiation exposure of the fiber scope used for in-vessel visual inspection. The measurement system, which requires a wide sensitivity range and high durability in a high-temperature environment, was specifically developed for use in the sodium cooled fast reactor. Using this system, the in-vessel gamma dose rate with cooling times of 450 and 720 days after reactor shutdown was measured in Joyo, which has been operated for 71,000 hours over approximately 30 years. The gamma dose rate was calculated using QAD-CGGP2 code with the gamma source intensity obtained by the ORIGEN2 code. The neutron flux used as input to the ORIGEN2 was evaluated by the Joyo dosimetry method. The ratio between the calculated and experimental values ranged from 1.1 to 2.4, confirming the accuracy of gamma dose rate and component activation calculation.
Hirayama, Ryoichi*; Uzawa, Akiko*; Matsumoto, Yoshitaka*; Noguchi, Miho; Kase, Yuki*; Takase, Nobuhiro*; Ito, Atsushi*; Koike, Sachiko*; Ando, Koichi*; Okayasu, Ryuichi*; et al.
Radiation Protection Dosimetry, 143(2-4), p.508 - 512, 2011/02
Times Cited Count：14 Percentile：71.96(Environmental Sciences)We studied double-strand breaks (DSB) induction and rejoining in clamped and non-clamped transplanted tumours in mice leg after exposure to 80 keV/
m carbon ions and X-rays. The yields of DSB in the tumours were analysed by a static-field gel electrophoresis. The OER of DSB after X-rays was 1.68, and this value was not changed after 1 h rejoining time (1.40). These damages in oxygenated conditions were rejoined 60-70% within 1 h in situ. No difference was found between the exposure to X-rays and carbon ions for the induction and rejoining of DSB. Thus, the values of OER and rejoined fraction after exposure to carbon ions were similar to those after X-rays, and the calculated relative biological effectivenesses of carbon ion were around 1 under both oxygen conditions. The yields of DSB in vivo depend on exposure doses, oxygen conditions and rejoining time, but not on the types of radiation quality.
Hirayama, Ryoichi*; Matsumoto, Yoshitaka*; Kase, Yuki*; Noguchi, Miho; Ando, Koichi*; Ito, Atsushi*; Okayasu, Ryuichi*; Furusawa, Yoshiya*
Radiation Physics and Chemistry, 78(12), p.1175 - 1178, 2009/12
Times Cited Count：12 Percentile：62.36(Chemistry, Physical)The contribution of OH radical-mediated indirect action by particle beams under hypoxic irradiation condition was investigated by using a radical scavenger. V79 cells were irradiated with 150 MeV/nucleon helium ions at an LET of 2.2 keV/mm in the presence or absence of DMSO, and their colony survivals were determined. The contribution of indirect action to cell killing under hypoxic condition was estimated to be 52 %. We conclude that OH radical mediated indirect action still has a half in total contribution on cell killing under hypoxic condition.
Hayashi, Kimio; Nakagawa, Tetsuya; Onose, Shoji; Ishida, Takuya; Nakamichi, Masaru; Katsuyama, Kozo; Iwamatsu, Shigemi; Hasegawa, Teiji; Kodaka, Hideo; Takatsu, Hideyuki; et al.
JAEA-Technology 2009-007, 168 Pages, 2009/03
JAEA-Technology-2009-007.pdf:31.88MB
In-pile functional tests of breeding blankets have been planned by Japan Atomic Energy Agency (JAEA), using a test blanket module (TBM) which will be loaded in the International Thermonuclear Experimental Reactor (ITER). In preparation for the in-pile functional tests, JAEA has been being performed irradiation experiments of lithium titanate (Li
TiO
), which is the first candidate of solid breeder materials for the blanket of the demonstration reactor (DEMO) under designing in Japan. The present report describes (1) results of a detailed design and trial fabrication tests of a dismantling apparatus for irradiation capsules which were used in irradiation experiments by the Japan Materials Testing Reactor (JMTR) of JAEA, and (2) results of a preliminary investigation of a glove box facility for post-irradiation examinations (PIEs). In the detailed design of the dismantling apparatus, datailed specifications and the installation methods were examined, based on results of a conceptual design and basic design. In the trial fabrication, cutting tests were curried out by making a mockup of a cutting component. Furthermore, a preliminary investigation of a glove box facility was carried out in order to secure a facility for PIE work after the capsule dismantling, which revealed a technical feasibility.
Hirayama, Ryoichi*; Ito, Atsushi*; Tomita, Masanori*; Tsukada, Teruyo*; Yatagai, Fumio*; Noguchi, Miho; Matsumoto, Yoshitaka*; Kase, Yuki*; Ando, Koichi*; Okayasu, Ryuichi*; et al.
Radiation Research, 171(2), p.212 - 218, 2009/02
Times Cited Count：118 Percentile：95.59(Biology)The biological effects of radiation originate principally in damages to DNA. DNA damages by X-rays as well as heavy ions are induced by a combination of direct and indirect actions. The contribution of indirect action in cell killing can be estimated from the maximum degree of protection by dimethylsulfoxide (DMSO), which suppresses indirect action without affecting direct action. Exponentially growing Chinese hamster V79 cells were exposed to high-LET radiations of 20 to 2106 keV/m in the presence or absence of DMSO and their survival was determined using a colony formation assay. The contribution of indirect action to cell killing decreased with increasing LET. However, the contribution did not reach zero even at very high LETs and was estimated to be 32% at an LET of 2106 keV/m. Therefore, even though the radiochemically estimated G value of OH radicals was nearly zero at an LET of 1000 keV/m, indirect action by OH radicals contributed to a substantial fraction of the biological effects of high-LET radiations. The RBE determined at a survival level of 10% increased with LET, reaching a maximum value of 2.88 at 200 keV/m, and decreased thereafter. When the RBE was estimated separately for direct action (RBE(D)) and indirect action (RBE(I)); both exhibited an LET dependence similar to that of the RBE, peaking at 200 keV/m. However, the peak value was much higher for RBE(D) (5.99) than RBE(I) (1.89). Thus direct action contributes more to the high RBE of high-LET radiations than indirect action does.
Ouchi, Nobuo; Akaoka, Nobuo*; Asano, Hiroyuki*; Chishiro, Etsuji; Namekawa, Yuya*; Suzuki, Hiroyuki*; Ueno, Tomoaki*; Noguchi, Shuichi*; Kako, Eiji*; Ouchi, Norihito*; et al.
Proceedings of 4th International Workshop on the Utilisation and Reliability of High Power Proton Accelerators, p.175 - 183, 2005/11
no abstracts in English
Yokoi, Koichi*; Noguchi, Yoshifumi*; Morita, Masaya*; Nakamura, Naoaki*; Takahara, Hiroyuki*; Moriya, Toshifumi*
PNC TJ1380 95-004, 235 Pages, 1995/03
None
Cho, Hisashi*; Yokoi, Koichi*; Noguchi, Yoshifumi*; Morita, Masaya*; Nakamura, Naoaki*; Takahara, Hiroyuki*; Moriya, Toshifumi*
PNC TJ1380 94-001, 1308 Pages, 1994/03
None
Hamabe, Shuji*; Cho, Hisashi*; Yokoi, Koichi*; Noguchi, Yoshifumi*; Iijima, Akio*; Morita, Masaya*; Nakamura, Naoaki*
PNC TJ4380 90-002, 463 Pages, 1990/05
None
Kagota, Eiichi; Noguchi, Koichi; Kitamura, Ryoichi; Abe, Kazuyuki
no journal, ,
no abstracts in English
Ashida, Takashi; Kaito, Yasuaki; Miyamoto, Kazuyuki; Noguchi, Koichi; Ito, Hideaki
no journal, ,
The MARICO-2 irradiation test part has been bent onto the in-vessel storage rack approximately 200 mm in horizontal length. As a result, the transfer pot in which the MARICO-2 irradiation test part has been installed can't be handled with the refueling machine. In order to confirm the condition of the bent MARICO-2 irradiation test subassembly and take the appropriate method, MARICO-2 lifting up test was conducted with a simple handling device which gripped the bent wrapper tube and lifted up the MARICO-2 irradiation test part approximately 40 mm. The test result confirmed that the MARICO-2 irradiation test part was stuck in the transfer pot due to the deformation of wrapper tube. Therefore, we will investigate the detail design of the MARICO-2 retrieval device with the fuel transfer pot and inspect whether the MARICO-2 is pulled out from the transfer pot.
Ashida, Takashi; Okazaki, Yoshihiro; Miyamoto, Kazuyuki; Noguchi, Koichi; Ito, Hideaki
no journal, ,
The 15th periodic inspection of Joyo commenced in May 2007 with the Fuel Handling Machine (FHM) being set up on the Rotating Plug (R/P) for refueling in June. When the R/P was taken down, measuring the load of the Hold-Down Shaft (HDS) revealed an abnormal decrease above the in-vessel storage rack (IVS). As a result of the observations, it was discovered that the top of the irradiation test S/A "MARICO-2"had bent onto the IVS as an obstacle, and had damaged the Upper Core Structure (UCS). The other action items in the restoration work, which are design of UCS and MARICO-2 handling device will be investigated in detail designs. The experience obtained through the restoration work in Joyo will provided valuable insights into possible further improvements and verifications for in-vessel inspection and repair techniques in SFRs.
Soga, Tomonori; Itagaki, Wataru; Noguchi, Koichi
no journal, ,
For the various irradiation tests, the compartment type rigs that set the coolant temperature individually, and the capsule type rig that can irradiate the advanced fuel pins, were developed in Joyo. Moreover, the online irradiation rigs which can measure or control the temperature with high accuracy had been developed and utilized in Joyo. These rigs contribute the basic research in the irradiation effect on material, and the research for the LWR or the fusion reactor. In addition, the high temperature irradiation test device, and the device which has function of the neutron energy spectrum tailoring will be prepared to expand the range of the irradiation condition. In PIE facilities that are adjacent to Joyo, parts of irradiation rigs or samples can be exchanged after irradiation. Then re-assembled rig can be re-loaded to Joyo. This technique enables to obtain the data on the way to the target burn-up or fluence, and to conduct the longer irradiation test than the lifetime of rigs.
Ota, Yasufumi; Saruta, Koichi; Noguchi, Shotaro; Ueda, Masashi
no journal, ,
no abstracts in English
Itagaki, Wataru; Noguchi, Koichi; Endo, Norio; Nakamura, Toshiyuki; Ashida, Takashi; Saito, Takakazu; Someya, Hiroyuki*; Tomine, Hiroshi*; Kato, Jun*; Gunji, Masakatsu*
no journal, ,
no abstracts in English
