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Sakamaki, Keiko; Kataoka, Masaharu; Maeda, Toshikatsu; Iida, Yoshihisa; Kamoshida, Michio; Yamaguchi, Tetsuji; Tanaka, Tadao
Corrosion Engineering, Science and Technology, 49(6), p.450 - 454, 2014/09
Times Cited Count:0 Percentile:0.00(Materials Science, Multidisciplinary)Corrosion experiments of a carbon steel plate embedded in bentonite mixture were conducted toverify our models assessing Eh evolution induced by corrosion of carbon steel overpack. Theexperimental results showed that the Eh decreased for the first 200 days and was subsequentlystabilised at around -450 mV; corrosion products were identified as magnetite and Fe waspresent mostly as divalent Fe within a 5 mm range from the carbon steel plate. Reactive transportmodelling was performed to assess the Eh evolution in the system using kinetic dissolution modelfor metallic iron and thermodynamic equilibrium models for other chemical reactions and closelyreproduced the experimental results. The models were verified only under the conditionsemployed in this study.
Yamaguchi, Tetsuji; Kataoka, Masaharu; Sawaguchi, Takuma; Mukai, Masayuki; Hoshino, Seiichi; Tanaka, Tadao; Marsal, F.*; Pellegrini, D.*
Clay Minerals, 48(2), p.185 - 197, 2013/05
Times Cited Count:3 Percentile:8.90(Chemistry, Physical)Highly alkaline environments induced by cement based materials are likely to deteriorate the physical and/or chemical properties of the bentonite buffer materials in radioactive waste repositories. Predicting long-term alteration of concrete/clay systems requires physico-chemical models and a number of input parameters. In order to provide reliability to the long-term prediction of bentonite buffer performance under disposal conditions, it is necessary to develop and verify reactive transport codes for concrete/clay systems. In this study, a PHREEQC-based, reactive transport analysis code (MC-CEMENT ver.2) was developed and was verified by comparing results of the calculations with observations of the mineralogical evolution at the concrete/argillite interface. The calculation reproduced the observations such as the mineralogical changes limited within one cm in thickness, formation of CaCO
and CSH, dissolution of quartz, decrease of porosity in argillite and increase in concrete. These agreements indicate possibility that the models based on lab-scale (
1 y) experiments can be applied to longer time scale. The fact that the calculation did not reproduce the dissolution of clays and the formation of gypsum indicates that there is still room for improvement in our model.
Sato, Kazuyoshi; Hashimoto, Masayoshi*; Nagamatsu, Nobuhide*; Yagenji, Akira; Sekiya, Shigeki*; Takahashi, Hideo*; Motohashi, Keiichi*; Ogino, Shunji*; Kataoka, Takahiro*; Ohashi, Hironori*; et al.
JAEA-Technology 2006-006, 587 Pages, 2006/03
no abstracts in English
Fukushima, Masahiro; Okajima, Shigeaki; Ando, Masaki; Yamane, Tsuyoshi; Kataoka, Masaharu*
JAERI-Research 2005-008, 57 Pages, 2005/03
no abstracts in English
Katakura, Junichi; Kataoka, Masaharu*; Suyama, Kenya; Jin, Tomoyuki*; Oki, Shigeo*
JAERI-Data/Code 2004-015, 115 Pages, 2004/11
A set of cross section libraries for ORIGEN2 code, ORLIBJ33, has been produced based on the latest Japanese Evaluated Nuclear Data Library JENDL-3.3. The produced libraries are for LWR's which include PWR, BWR and their MOX fuels. The libraries for FBR's are also produced. Using the libraries for LWR, comparisons with old libraries based on JENDL-3.2 were performed. The comparisons with measured PIE data were also carried out. For the libraries for FBR, the comparisons with the calculations using the old libraries were performed and the effects using different libraries were discussed.
Kojima, Kensuke; Okajima, Shigeaki; Yamane, Tsuyoshi; Ando, Masaki; Kataoka, Masaharu*; Iwanaga, Kohei
JAERI-Tech 2004-016, 38 Pages, 2004/03
To investigate the void coefficient in the Reduced-Moderation Water Reactor (RMWR), an infinite multiplication factor was measured in the FCA-XXII-1 (65V) core. Axial and radial fission rate distributions were measured by micro fission chambers with four different kinds of nuclides. The infinite multiplication factor was derived from the material buckling, which was obtained from both the axial and radial fission rate distributions, and the migration area calculated. The value of it in the test region of the FCA-XXII-1 (65V) core was 1.3440.034. It was compared with the calculation, the ratio of the calculation to the measurement was 1.008
0.026. The improvement in measurement accuracy was also considered.
Kataoka, Masaharu; Mukai, Masayuki; Sawaguchi, Takuma; Tsukada, Manabu; Kadowaki, Mitsushi*; Maeda, Toshikatsu; Tanaka, Tadao
no journal, ,
no abstracts in English
Kataoka, Masaharu; Tsukada, Manabu; Mukai, Masayuki; Sawaguchi, Takuma; Kadowaki, Mitsushi*; Maeda, Toshikatsu; Tanaka, Tadao
no journal, ,
no abstracts in English
Mukai, Masayuki; Sawaguchi, Takuma; Kataoka, Masaharu; Tsukada, Manabu; Maeda, Toshikatsu; Tanaka, Tadao
no journal, ,
In the Japanese HLW disposal program, vitrified HLW is encapsulated in a steel container called overpack, and placed in a repository surrounded with bentonite clay material in an underground site. Bentonite is planed to be used as buffer material to prevent from contacting overpack with huge volume of groundwater for extended period of post-closure. Cementinious material affects on surrounding groundwater to alkalize and that probably deteriorates the low hydraulic conductivity of bentonite. JAEA, therefore, has been developed evaluation methodology to calculate long-term performance of bentonite in alkaline groundwater condition by means of concurrent calculations of chemical-reaction and mass-transport, combining with key models formulated mainly on experimentally basis.
Kataoka, Masaharu; Tsukada, Manabu; Mukai, Masayuki; Sawaguchi, Takuma; Kadowaki, Mitsushi*; Maeda, Toshikatsu; Tanaka, Tadao
no journal, ,
no abstracts in English
Maeda, Toshikatsu; Omori, Hiroyuki; Yamaguchi, Tetsuji; Kataoka, Masaharu; Bamba, Tsunetaka*
no journal, ,
no abstracts in English
Mukai, Masayuki; Kataoka, Masaharu; Takeda, Seiji; Maeda, Toshikatsu; Iida, Yoshihisa; Watanabe, Masatoshi; Sawaguchi, Takuma; Yamaguchi, Tetsuji; Tanaka, Tadao
no journal, ,
Systematic safety assessment should be carried out taking into account linkage among "Condition Setting", "Safety Function", and "Radionuclide Migration". We have summarized input-output relation among a calculation code coupled mass transport and chemical reaction, models to evaluate performance of each of engineered barriers, and a safety assessment code through the viewpoint of the linkage. As the first step to establish a systematic safety assessment methodology, how to specifically link those codes and models and how to apply a linked calculation process to practical cases of geological disposal conditions have been discussed.
Hirota, Naoki; Kataoka, Masaharu; Mukai, Masayuki; Yamaguchi, Tetsuji
no journal, ,
no abstracts in English
Kataoka, Masaharu; Mukai, Masayuki; Hirota, Naoki; Yamaguchi, Tetsuji
no journal, ,
no abstracts in English
Mukai, Masayuki; Kataoka, Masaharu; Iida, Yoshihisa; Maeda, Toshikatsu; Hirota, Naoki; Yamaguchi, Tetsuji; Tanaka, Tadao
no journal, ,
Performance evaluation models for engineered barriers and estimation methods for radionuclide migration parameters have been developed to establish a method of long-term safety assessment for geological disposal simulating a variety of environmental conditions of deep underground in Japan. In order to make the safety assessment more systematic and reasonable, the parameters used in radionuclide migration analysis should reflect spatially and temporally changeable conditions of the engineered barriers. Moreover, the changeable conditions should be quantified based on the calculation in which models and parameters for the barrier materials are systematically linked with each other. In this study, a sequence of the systemized procedure was configured and was tested to pick out parameters having significant influence to the safety function of the buffer material from results of long-term performance analysis on engineered barrier system.
Tsukada, Manabu; Kadowaki, Mitsushi*; Mukai, Masayuki; Sawaguchi, Takuma; Kataoka, Masaharu; Maeda, Toshikatsu; Tanaka, Tadao
no journal, ,
no abstracts in English
Sawaguchi, Takuma; Kadowaki, Mitsushi*; Mukai, Masayuki; Tsukada, Manabu; Kataoka, Masaharu; Maeda, Toshikatsu; Tanaka, Tadao
no journal, ,
no abstracts in English
Sakamaki, Keiko; Otsuka, Ichiro*; Iida, Yoshihisa; Inada, Daisuke*; Kamoshida, Michio; Kataoka, Masaharu; Yamaguchi, Tetsuji; Tanaka, Tadao
no journal, ,
no abstracts in English
Suyama, Kenya; Akie, Hiroshi; Kataoka, Masaharu*; Yamamoto, Kento*
no journal, ,
no abstracts in English
Akie, Hiroshi; Kataoka, Masaharu*; Suyama, Kenya
no journal, ,
no abstracts in English