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Harada, Hideo; Nakamura, Shoji; Hatsukawa, Yuichi; Toh, Yosuke; Kimura, Atsushi; Ishiwatari, Yuki*; Yasumi, Atsushi*; Mabuchi, Yukio*; Nakagawa, Tsutomu*; Okamura, Kazuo*; et al.
Journal of Nuclear Science and Technology, 46(5), p.460 - 468, 2009/05
Times Cited Count:4 Percentile:30.36(Nuclear Science & Technology)The neutron capture cross section of Np has been measured for fast neutrons supplied at the center of the core in the Yayoi reactor. The activation method was used for the measurement, in which the amount of the product Np was determined by -ray spectroscopy using a Ge detector. The representative neutron energy and the corresponding capture cross section of Np in the experiment were analytically deduced as 0.80 0.04 b at 0.214 0.009 MeV from the measured reaction rate by combining the energy dependence of the cross section in the nuclear data library ENDF/VII.0. The deduced cross section of Np at the representative neutron energy agrees with the evaluated data of ENDF/B-VII.0, but shows 15% larger value than that of JENDL-3.3 and 13% larger value than that of JENDL/AC-2008.
Takahashi, Shuichi*; Yoshida, Masaru; Asano, Masaharu; Notomi, Mitsuo*; Nakagawa,Tsutomu*
Nuclear Instruments and Methods in Physics Research B, 217(3), p.435 - 441, 2004/05
Times Cited Count:15 Percentile:68.07(Instruments & Instrumentation)Various characterization were used to study the effect of heavy ion irradiation on a poly(ethylen terephthalate)(PET) membrane. My study was followed using some dynamic and thermal measurements with the aim to undestand the chemical change in the material by heavy ion irradiation. The anyalyese included DMA, tensile measurement, DSC and micro-FT-IR. The overall structure change in the PET polymer was investigated as a function of the Xe ion fluence in the range from 310 to 310ions/cm. Based on some mechanical measurements such as the tensile analysis and dynamic test, the heavy ion irradiated PET membranes exhibited a significant change in cross-linking. I believe that the secondary electron induced by collision between the irradiated ion and the constituent atoms of the membrane material form the cross-linking. The polymer chain scission and structure degradations are expected to result at higher ion fluence. Also, a slight change in the structure such as amorphization has been shown by DSC and the micro-FT-IR test.
Takahashi, Shuichi*; Yoshida, Masaru; Asano, Masaharu; Nakagawa,Tsutomu*
Polymer Journal, 36(1), p.50 - 53, 2004/01
Times Cited Count:4 Percentile:16.06(Polymer Science)The poly(ethylen terephthalate)(PET) membrane, which has a membrane thickness of 12m, was used in this study. PET is a polymer widely used for fibers, films and bottles. It was assumed that for PET, which is often used as a gas barrier film, it is easy to effect changes in its gas permeability by modification, such as by ion irradiation. Previously, I reported the effect of heavy ion irradiation on the gas permeation of a PET membrane. A portion of the heavy ion irradiated PET membranes exhibited the Knudsen flow during the gas permeation measurements. As a next step, therefore, I applied an etching technique utilizing NaOH solution to control the nanosized pore of the heavy ion irradiated PET membrane. PET membranes irradiated at a fluence of 310 ions/cm were etched in 6N or 1N NaOH solution at 60C. The etching time was controlled to observe the changes in the gas permeation behavior depended on the etchig. This objective has consequently been used to control the Knudsen flow.
Igarashi, Shinichi; Asami, Tetsuo; Kikuchi, Yasuyuki; Nakagawa, Tsuneo; Narita, Tsutomu; Shibata, Keiichi
Nihon Genshiryoku Gakkai-Shi, 26(3), p.191 - 198, 1984/00
Times Cited Count:3 Percentile:38.11(Nuclear Science & Technology)no abstracts in English
; Nakagawa, Tsuneo; Kikuchi, Yasuyuki; Asami, Tetsuo; Narita, Tsutomu
JAERI 1261, 206 Pages, 1979/03
no abstracts in English
Nakagawa, Katsuya*; Oshima, Tsutomu*; Kodaka, Shuichi*; Ishii, Yoshikane*
PNC TJ199 79-03, 209 Pages, 1979/02
no abstracts in English
Narita, Tsutomu; ; Nakagawa, Tsuneo;
JAERI-M 5769, 24 Pages, 1974/07
no abstracts in English
Nakamura, Shoji; Toh, Yosuke; Kimura, Atsushi; Hatsukawa, Yuichi; Harada, Hideo; Ishiwatari, Yuki*; Saito, Isao*; Yasumi, Atsushi*; Mabuchi, Yukio*; Nakagawa, Tsutomu*; et al.
no journal, ,
no abstracts in English
Harada, Hideo; Nakamura, Shoji; Hatsukawa, Yuichi; Toh, Yosuke; Kimura, Atsushi; Ishiwatari, Yuki*; Yasumi, Atsushi*; Mabuchi, Yukio*; Nakagawa, Tsutomu*; Oka, Yoshiaki*
no journal, ,
Neutron capture cross section of Np for fast neutrons has been measured using an activation method. A small amount of Np sample was irradiated in the Grazing hole of the Yayoi reactor. The neutron flux at the irradiation point was monitored by Au activation foil. The duduced neutron capture cross section was compared with those in nuclear data libraries JENDL-3.3 and ENDF/B-VII.0.
Nakamura, Shoji; Hatsukawa, Yuichi; Toh, Yosuke; Kimura, Atsushi; Harada, Hideo; Ishiwatari, Yuki*; Yasumi, Atsushi*; Nakagawa, Tsutomu*; Mabuchi, Yukio*; Saito, Isao*; et al.
no journal, ,
The Np sample was irradiated at the Gz hole of YAYOI reactor, and the fast-neutron capture cross-section was obtained by an activation method. The production amount of Np was measured by -ray spectroscopy. The neutron flux at the irradiation position was monitored by a gold foil. It was found that the present result of the fast-neutron capture cross-section was 15% larger than that in JENDL-3.3.
Nakamura, Shoji; Hatsukawa, Yuichi; Toh, Yosuke; Kimura, Atsushi; Harada, Hideo; Ishiwatari, Yuki*; Yasumi, Atsushi*; Nakagawa, Tsutomu*; Mabuchi, Yukio*; Saito, Isao*; et al.
no journal, ,
Technetium-99 samples were irradiated by fast neutrons at YAYOI reactor. The fast-neutron capture cross-section was measured by the activation method.
Nakamura, Shoji; Toh, Yosuke; Hatsukawa, Yuichi; Kimura, Atsushi; Harada, Hideo; Yasumi, Atsushi*; Nakagawa, Tsutomu*; Mabuchi, Yukio*; Saito, Isao*; Ishiwatari, Yuki*
no journal, ,
The fast-neutron capture cross section of I was measured at the YAYOI reactor by the activation method. The amount of I was obtained by measuring -rays emitted from I. The neutron flux was monitored by a piece of gold foil. The fast-neutron capture cross section was derived from the information of the production amount of I and the neutron flux. This work found that the evaluated data might be overestimated by about 10% and more.