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Terashima, Taku*; Matsuda, Yasuhiro*; Kuga, Kentaro*; Suzuki, Shintaro*; Matsumoto, Yosuke*; Nakatsuji, Satoru*; Kondo, Akihiro*; Kindo, Koichi*; Kawamura, Naomi*; Mizumaki, Masaichiro*; et al.
Journal of the Physical Society of Japan, 84(11), p.114715_1 - 114715_4, 2015/11
Times Cited Count:4 Percentile:33.40(Physics, Multidisciplinary)Emi, Naoya*; Hamabata, Ryosuke*; Nakayama, Daisuke*; Miki, Toshihiro*; Koyama, Takehide*; Ueda, Koichi*; Mito, Takeshi*; Kohori, Yo*; Matsumoto, Yuji*; Haga, Yoshinori; et al.
Journal of the Physical Society of Japan, 84(6), p.063702_1 - 063702_4, 2015/06
Times Cited Count:10 Percentile:56.88(Physics, Multidisciplinary)Terashima, Taku*; Matsuda, Yasuhiro*; Kuga, Kentaro*; Suzuki, Shintaro*; Matsumoto, Yosuke*; Nakatsuji, Satoru*; Kondo, Akihiro*; Kindo, Koichi*; Kawamura, Naomi*; Mizumaki, Masaichiro*; et al.
Journal of Physics; Conference Series, 592(1), p.012020_1 - 012020_6, 2015/03
Times Cited Count:1 Percentile:41.96(Physics, Atomic, Molecular & Chemical)Valence fluctuation phenomena in rare-earth intermetallic compounds have attracted attention because the quantum criticality of the valence transition has been proposed theoretically. Recently, it was found that -YbAlB
shows quantum criticality without tuning and has a strong mixed-valence state. In this study, we measured the magnetization curve and X-ray magnetoabsorption in
-YbAl
Fe
B
(
), which is a locally isostructural polymorph of
-YbAlB
. The magnetization and X-ray experiments were performed in fields up to 55 and 40 T, respectively. A small increase in the Yb valence was observed at fields where the magnetization curve exhibited a change in slope.
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:27 Percentile:62.33(Biotechnology & Applied Microbiology)Nishiuchi, Mamiko; Pirozhkov, A. S.; Sakaki, Hironao; Ogura, Koichi; Esirkepov, T. Z.; Tanimoto, Tsuyoshi; Kanasaki, Masato; Yogo, Akifumi; Hori, Toshihiko; Sagisaka, Akito; et al.
Physics of Plasmas, 19(3), p.030706_1 - 030706_4, 2012/03
Times Cited Count:6 Percentile:24.80(Physics, Fluids & Plasmas)A 7 MeV proton beam collimated to 16 mrad containing more than particles is experimentally demonstrated by focusing a 2J, 60 fs pulse of a Ti:sapphire laser onto targets of different materials and thicknesses placed in a millimeter scale conical holder. The electric potential induced on the target holder by laser-driven electrons accelerates and dynamically controls a portion of a divergent quasi-thermal proton beam originated from the target, producing a quasi-monoenergetic "pencil" beam.
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:70.49(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.
Hayakawa, Misa; Matsumoto, Koichi*; Uda, Norihiko*
Toshokan Joho Medeia Kenkyu, 8(1), p.57 - 69, 2010/09
The database of the image and related text of Taoist charms (Fu), which appear in the Taoist ritual book "Dao-fa Hui-yuan", has been built to help researchers in this college. And many analysis tool has been built up, for example, analysis system of "Parts", which is component of "Fu". However, if researchers want to use these tools, they are not useful unless the relation of the forms and the meanings of "Parts", which is given to each "Parts" in analysis style are definitly. The former database didn't contain all "Fu" and "Parts" of "Dao-fa Hui-yuan". Therefore, analysis tools couldn't use for research of "Dao-fa hui-yuan". In this study, we created "Fu" and "Parts" data which appear in "Dao-fa Hui-yuan" after volume 56, and created a classified list of "Parts". We analyzed about the tendency of distributions of "Parts", taking the relations of "Parts" and their meanings into consideration, and considered the relations of the tendency of distributions to Taoist sects.
Hakoda, Teruyuki; Matsumoto, Kanae*; Mizuno, Akira*; Hirota, Koichi
International Journal of Plasma Environmental Science & Technology, 4(1), p.65 - 70, 2010/03
The catalytic effect of Pt/AlO
and Ag/Al
O
on the oxidation of xylene in air was studied at a constant temperature of 373 K, when they were combined with electron-beam (EB)-induced non-thermal plasmas (NTPs). The presence of a catalyst bed was found to enhance the oxidation of the irradiation products of xylene. However, the degree of catalytic oxidation was different depending on the type of loaded metal and the position of the catalyst bed. Compared with a Al
O
bed, a Pt/Al
O
bed in the NTP space suppressed oxidation, while an Ag/Al
O
bed downstream of the NTP space enhanced it. Under low temperature conditions, Pt/Al
O
was not a suitable catalyst for the oxidation of organics in combination with the NTP process. On the other hand, the Ag/Al
O
catalyst was a preferable catalyst for the NTP-induced oxidation of organics under such low temperature conditions.
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:13 Percentile:63.72(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.
Hakoda, Teruyuki; Matsumoto, Kanae*; Mizuno, Akira*; Hirota, Koichi
Applied Catalysis A; General, 357(2), p.244 - 249, 2009/04
Times Cited Count:16 Percentile:37.05(Chemistry, Physical)Catalytic oxidation of xylene in air was performed under electron beam (EB) irradiation using pure TiO as well as TiO
loaded with Ag, Pt, Au, and Mn to clarify the role of loaded metal in the enhancement of oxidation of xylene and its irradiation byproducts to CO
in EB-induced non-thermal plasma. EB irradiation experiments were performed with the catalyst bed placed in both irradiated and non-irradiated spaces. The highest conversion percentage of decomposed xylene to CO
was obtained by irradiation/catalytic oxidation using an Ag/TiO
bed placed in a non-irradiated space. The greater enhancement of CO
production on an Ag/TiO
pellet surface compared to that on other metal-loaded TiO
pellet surfaces was due to the synergetic effect of strong adsorption of the byproducts on the Ag loaded on TiO
and production of active oxygen from decomposition of O
in the presence of Ag.
Hakoda, Teruyuki; Shimada, Akihiko; Matsumoto, Kanae*; Hirota, Koichi
Plasma Chemistry and Plasma Processing, 29(1), p.69 - 78, 2009/02
Times Cited Count:6 Percentile:26.32(Engineering, Chemical)Electron beam (EB) technology has an advantage for treating dilute environmental pollutants in gases due to high-density population of active species such as radicals and atoms. In general, OH radicals play an important role of initiating the decomposition and removal of such pollutants. It is quite important to understand the behavior of OH radical production for the development of efficient decomposition/removal processes and the comparison with other purification methods. The number of OH radicals produced in humid N at doses of 2.0-10.0 kGy with dose rates of 0.17-2.55 kGy/s under 1-MeV EB irradiation was indirectly determined using an index of oxidation of CO to CO
, which has been used in atmospheric chemistry. An experiment under conditions where all OH radicals produced react with CO demonstrated that the concentration of CO
increased linearly with doses of 0-10 kGy, and the
(OH) was estimated as 4.90.
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:127 Percentile:95.86(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.
Hakoda, Teruyuki; Matsumoto, Kanae; Mizuno, Akira*; Narita, Tadashi*; Kojima, Takuji; Hirota, Koichi
IEEE Transactions on Industry Applications, 44(6), p.1950 - 1956, 2008/11
Times Cited Count:3 Percentile:33.65(Engineering, Multidisciplinary)Oxidation of xylene and its irradiation-induced organic byproducts in air using Ag-loaded TiO (Ag/TiO
) beds was studied under electron beam (EB) irradiation. The Ag/TiO
beds were placed in an irradiation or a non-irradiation space in order to identify the oxidation of xylene/its byproducts by EB irradiation, by catalytic process, and by a combination of the two. Placement of the Ag/TiO
bed to the irradiation space resulted in the suppression of xylene decomposition. On the other hand, production of CO
was observed in the gas phase of the irradiation space and on the surface of the Ag/TiO
pellets placed both in the irradiation and non-irradiation spaces. The concentration of CO
became higher when the layer was placed in the non-irradiation space. The production of CO
was enhanced by loading of Ag to the TiO
pellet surface. The highest concentration of CO
was obtained for Ag/TiO
with Ag contents greater than 5wt%.
Hakoda, Teruyuki; Matsumoto, Kanae*; Mizuno, Akira*; Hirota, Koichi
Journal of Physics D; Applied Physics, 41(15), p.155202_1 - 155202_7, 2008/08
Times Cited Count:3 Percentile:14.15(Physics, Applied)The oxidation of xylene and its irradiation byproducts in air using a -Al
O
bed was studied under electron-beam irradiation to enhance the decomposition of volatile organic compounds in ventilation gases emitted from paint factories. The use of the
-Al
O
bed enhanced the oxidation of the irradiation byproducts to CO
. Furthermore, the oxidation of the byproducts was accelerated by the placement of the
-Al
O
bed in an irradiation space, because of the interaction of primary electrons with the surface of
-Al
O
pellets. This combined oxidation process enabled a reduction in the energy consumption for non-toxic CO
formation, and improved the selectivity of CO
production.
Hakoda, Teruyuki; Matsumoto, Kanae; Shimada, Akihiko; Narita, Tadashi*; Kojima, Takuji; Hirota, Koichi
Radiation Physics and Chemistry, 77(5), p.585 - 590, 2008/05
Times Cited Count:9 Percentile:51.63(Chemistry, Physical)The electron beam (EB) oxidation of gaseous xylene in air, appearing as ventilation gases emitted from painting factories, was investigated under various experimental conditions. Thereby the implementation of an ozone decomposition catalyst, MnO, into EB-induced oxidation of xylene/air mixtures strongly contributed in the achievement of a better purification degree.
Hakoda, Teruyuki; Matsumoto, Kanae; Mizuno, Akira*; Kojima, Takuji; Hirota, Koichi
Plasma Chemistry and Plasma Processing, 28(1), p.25 - 37, 2008/02
Times Cited Count:22 Percentile:62.74(Engineering, Chemical)The oxidation of xylene and its irradiation byproducts in air using TiO was studied under electron beam (EB) irradiation for the purification of ventilation gases emitted from paint factories. EB irradiation experiments were performed mainly under two different conditions: a TiO
pellet layer was placed in an irradiation or non-irradiation space. The results revealed that xylene was decomposed and CO was formed in the gas phase of the irradiation space irrespective of the presence of the TiO
pellets, while CO
was produced in the gas phase of the irradiation space and on the surface of the TiO
pellets. The total CO
concentration increased when the pellet layer was in the non-irradiation space. On the other hand, the concentration of CO
produced on the surface of the TiO
pellets in the irradiation space was higher than that in a non-irradiation space.
Kakudate, Satoshi; Oka, Kiyoshi; Yoshimi, Takashi*; Hiyama, Masayuki; Taguchi, Ko*; Shibanuma, Kiyoshi; Koizumi, Koichi; Matsumoto, Yasuhiro*; Honda, Tsutomu*; Haange, R.*
Nuclear Fusion, 42(3), p.243 - 246, 2002/03
Times Cited Count:3 Percentile:10.56(Physics, Fluids & Plasmas)no abstracts in English
Matsumoto, Yasuyo*; Matsuura, Yuki*; Hibino, Yutaka*; Kawakami, Koichi*; Komaki, Yoshihide; ; Sakurai, Tsutomu; Tachikawa, Enzo
JAERI-M 93-196, 40 Pages, 1993/10
no abstracts in English
Kasai, Satoshi; Miura, Yukitoshi; Sengoku, Seio; Hasegawa, Koichi; Ogawa, Hiroaki; Uesugi, Yoshihiko; Tamai, Hiroshi; Kawashima, Hisato; Hasegawa, Mitsuru*; Hoshino, Katsumichi; et al.
JAERI-M 87-159, 17 Pages, 1987/10
no abstracts in English
Kotani, Koichi*; Nakao, Toshitsugu*; Sumida, Isao*; Yokomizo, Osamu*; Matsumoto, Tomoyuki*
Journal of Nuclear Science and Technology, 17(10), p.791 - 793, 1980/10