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Dobashi, Kunio*; Shimizu, Yasuo*; Matsuzaki, Shinichi*; Nagamine, Takeaki*; Sato, Takahiro; Okubo, Takeru; Yokoyama, Akihito; Ishii, Yasuyuki; Kamiya, Tomihiro; Arakawa, Kazuo*; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 87, 2012/01
Matsuzaki, Shinichi*; Shimizu, Yasuo*; Dobashi, Kunio*; Nagamine, Takeaki*; Sato, Takahiro; Okubo, Takeru; Yokoyama, Akihito; Ishii, Yasuyuki; Kamiya, Tomihiro; Arakawa, Kazuo*; et al.
International Journal of Immunopathology and Pharmacology, 23(1), p.1 - 11, 2010/01
Hirata, Yosuke*; Nakahara, Katsuhiko*; Sano, Akira*; Sato, Mitsuyoshi*; Aoyama, Yoshio; Miyamoto, Yasuaki; Yamaguchi, Hiromi; Nambu, Kenichi*; Takahashi, Hiroyuki*; Oda, Akinori*
Journal of Power and Energy Systems (Internet), 2(2), p.561 - 572, 2008/00
Aoyama, Yoshio; Miyamoto, Yasuaki; Yamaguchi, Hiromi; Sano, Akira*; Naito, Susumu*; Sumida, Akio*; Izumi, Mikio*; Maekawa, Tatsuyuki*; Sato, Mitsuyoshi*; Nambu, Kenichi*; et al.
Proceedings of 15th International Conference on Nuclear Engineering (ICONE-15) (CD-ROM), 6 Pages, 2007/04
no abstracts in English
Hirata, Yosuke*; Nakahara, Katsuhiko*; Sano, Akira*; Sato, Mitsuyoshi*; Aoyama, Yoshio; Miyamoto, Yasuaki; Yamaguchi, Hiromi; Nambu, Kenichi*; Takahashi, Hiroyuki*; Oda, Akinori*
Proceedings of 15th International Conference on Nuclear Engineering (ICONE-15) (CD-ROM), 6 Pages, 2007/04
no abstracts in English
Naito, Susumu*; Sano, Akira*; Izumi, Mikio*; Noda, Etsuo*; Hayashi, Kazuo*; Sato, Mitsuyoshi*; Suto, Osamu; Miyamoto, Yasuaki; Kondo, Shinichi*; Iinuma, Koichi*; et al.
Nuclear Science Symposium Conference Record, 2005 IEEE, Vol.1, p.495 - 499, 2005/10
An alpha radioactivity monitor (alpha-clearance monitor) is being developed to measure alpha radioactivity of uranium contaminated waste with large and complex surfaces. It uses an alpha radioactivity measurement method by collecting the air ionized by alpha particles using an air stream and by measuring its ion current. One of the major problems of the alpha-clearance monitor is the background ion current mainly by radon in atmosphere (
700 fA), which is much larger than ion current of an alpha particle (several fA). It strongly influences on the detection limit of alpha radioactivity. In order to improve the detection limit, we developed a method to monitor the radon concentration inside the monitor without the additional radon detector. In addition, the influencing factors on the detection limit: ion mobility and ion recombination coefficient were measured and evaluated on various environmental conditions (temperature, humidity and aerosol density).
Miyamoto, Shinya*; Sato, Mitsuyoshi*; Mihara, Morihiro
JNC TN8400 2005-028, 21 Pages, 2005/09
JNC-TN8400-2005-028.pdf:25.6MB
It is planning that radioactive wastes of high alpha concentration generated from reprocessing plant of spent nuclear fuel will be disposed in deep underground repository in Japan. Using the nitrate acid in the reprocessing process, some of radioactive wastes include lots of nitrate salts. The solubility of nitrate salts is very high and they might easily dissolve in groundwater in the repository. In the repository, many steels also will be disposed and nitrate will be reduced to ammonium ion by the interaction of steel. In this study, first the solubility experiments of nickel were performed to evaluate the effect of ammonium ion on solubility. Next the geochemical modeling also was carried out to explain results of solubility experiments using published thermodynamic data of nickel and ammonia. Under conditions of more than 1mol/dm
of ammonium chloride, the enhancement of solubility of nickel was observed. It showed 2 or 3 orders magnitude of higher than those of less than 1mol/dm of ammonium chloride. These data were explained by geochemical modeling using data of ammine complex.
Kato, Hiroshige*; Sato, Mitsuyoshi*; Owada, Hitoshi*; Mihara, Morihiro;
JNC TN8430 2000-008, 53 Pages, 2000/05
Cementitious materials will be used in TRU waste disposal repository. In such cases, it is considered that the migration of alkaline leachates from cementitious materials, so called high pH plume, will cause dissolution of rock and precipitation of secondary minerals. In addition, the high pH plume will move along the flow of groundwater, so it is predicted that rock formation and components of high pH groundwater vary with time and space. However, time and spatial dependence of the variations of secondary minerals and groundwater components has not been clarified. In order to acquire the data of variations of secondary minerals and groundwater components, we carried out the rock alteration experiments with column method. The crushed granodiorite was filled into 4 meters length column (
3.7 cm) and artificial cement leachate (pH=13.3; Na=0,1 mol/l, K=0.1 mol/l, Ca=0.002 mol/l) was streamed at flow rates of 0.1 ml/min for 7 months at 80
C. As the result, secondary minerals confirmed on the rock were calcite and C-S-H at upstream of column and C-S-H at mid-downstream. The pH value of the fluid dominated by Na and K did not be decreased by reaction with the rock. In this study, the data relating to the effect of high pH plume on rock over the long term was acquired.
Oda, Chie; Isogai, Takeshi*; Sato, Mitsuyoshi*
JNC TN8400 2000-006, 104 Pages, 1999/11
no abstracts in English
Oda, Chie; Isogai, Takeshi*; Sato, Mitsuyoshi*; Shibata, Masahiro
JNC TN8400 99-015, 35 Pages, 1999/03
None
Miyamoto, Yasuaki; Yamaguchi, Hiromi; Hirata, Yosuke*; Sano, Akira*; Sato, Mitsuyoshi*; Nambu, Kenichi*; Takahashi, Hiroyuki*; Oda, Akinori*
no journal, ,
no abstracts in English
Aoyama, Yoshio; Miyamoto, Yasuaki; Yamaguchi, Hiromi; Sano, Akira*; Naito, Susumu*; Sumida, Akio*; Sato, Mitsuyoshi*; Nambu, Kenichi*; Takahashi, Hiroyuki*; Oda, Akinori*
no journal, ,
no abstracts in English
Aoyama, Yoshio; Miyamoto, Yasuaki; Yamaguchi, Hiromi; Naito, Susumu*; Sano, Akira*; Hirata, Yosuke*; Noda, Etsuo*; Sato, Mitsuyoshi*; Nambu, Kenichi*; Takahashi, Hiroyuki*; et al.
no journal, ,
no abstracts in English
Aoyama, Yoshio; Miyamoto, Yasuaki; Yamaguchi, Hiromi; Hirata, Yosuke*; Naito, Susumu*; Sano, Akira*; Nakahara, Katsuhiko*; Sato, Mitsuyoshi*; Nambu, Kenichi*; Takahashi, Hiroyuki*; et al.
no journal, ,
no abstracts in English
Aoyama, Yoshio; Miyamoto, Yasuaki; Yamaguchi, Hiromi; Naito, Susumu*; Sano, Akira*; Izumi, Mikio*; Sumida, Akio*; Maekawa, Tatsuyuki*; Sato, Mitsuyoshi*; Nambu, Kenichi*; et al.
no journal, ,
Radioactive waste contaminated by Uranium has been accumulated in front-end facilities of the nuclear fuel cycle. The purpose of the present project is to develop the practical and highly efficient measurement system, which solves the above-mentioned requirements based on the innovative concept of indirect alpha radioactivity measurement using ionized air stream transportation. The ionized air by alpha particles near the waste is peeled and transported into the ion sensor by controlling air stream in the measurement system. In order to give the actual solution for this indirect measurement concept, we have to clarify various basic physics concerning with radiation ionizing process in the air, ion reaction process in the air, ion transportation process by the turbulent air flow, and measurement process in the ion sensor. For this purpose, we have to develop various analytical simulation technologies for predicting ion behavior as well as direct measurement technologies of ion spatial distribution. The final target of the project is to establish the practical and verified clearance confirmation technology based on the above-mentioned physical and technological knowledge.
