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Ishidera, Takamitsu; Kurosawa, Seiichi*; Hayashi, Masanori*; Uchikoshi, Keiji*; Beppu, Hikari*
Clay Minerals, 51(2), p.161 - 172, 2016/05
Times Cited Count:4 Percentile:14.18(Chemistry, Physical)The sorption and diffusion behavior of Cs in illite-added compacted montmorillonite was investigated by through-diffusion experiment. The obtained distribution coefficient of Cs for the illite-added compacted montmorillonite was several times larger than that for the montmorillonite without illite, while no increase of effective diffusion coefficient was observed for the illite-added compacted montmorillonite. The dominant sorption site of Cs on illite is considered to be the frayed edge site (FES) considering the Cs concentration in this experiment. Therefore, the surface diffusion of Cs sorbing on the FES on illite surface was considered to be negligible in compacted montmorillonite.
Sakuraba, Naotoshi; Numata, Masami; Komiya, Tomokazu; Ichise, Kenichi; Nishi, Masahiro; Tomita, Takeshi; Usami, Koji; Endo, Shinya; Miyata, Seiichi; Kurosawa, Tatsuya; et al.
JAEA-Technology 2009-071, 34 Pages, 2010/03
As a part of maintenance technology of a large-sized glove box for handling of TRU nuclides, we developed replacement technology for front acrylic panels using the bag-in/bag-out method and applied this technology to replace the deteriorated front acrylic panels at Waste Safety Testing Facility (WASTEF) in Nuclear Science Research Institute of Japan Atomic Energy Agency (JAEA). As a consequence, we could safely replace the front acrylic panels under the condition of continuous negative pressure only with partial decontamination of the glove box. We also demonstrated that the present technology is highly effective in points of safety, workability and cost as compared to the usual replacement technology for front acrylic panels of a glove box, where workers in an air-line suit replace directly the front acrylic panels in a green house.
Iijima, Kazuki; Yoshikawa, Hideki; Kurosawa, Seiichi*
no journal, ,
Diffusion behavior of humic acid in compacted bentonite was investigated with Kunigel V1 in 0.1M NaCl solution. In case of 1.2 Mg/m of dry density, breakthrough of the fumic acid was observed after 100 days. On the other hand, in case of 1.6 and 1.8 of dry density, no breakthrough was observed even after 500 days. Based on the measurement of size distribution of humic acid by GPC, it is suggested that relatively bigger humic acid cannot diffuse but smaller one due to the filtration effect of compacted bentonite.
Ishidera, Takamitsu; Kurosawa, Seiichi*
no journal, ,
no abstracts in English
Ishidera, Takamitsu; Tran, P.*; Kurosawa, Seiichi*; Kibe, Satoshi*
no journal, ,
no abstracts in English
Iijima, Kazuki; Kurosawa, Seiichi*; Tobita, Minoru*; Kibe, Satoshi*
no journal, ,
Diffusion behavior of humic acid in compacted bentonite was investigated by through-diffusion experiments under the conditions with various dry density and NaCl concentration. Limitation of filtration effect of the compacted bentonite with 1.2 Mg m of dry density in 1 mol dm of NaCl solution is around 3,000 of molecular weight, based on the molecular weight distribution of humic acid before and after the experiment measured by size exclusion chromatography.
Ishidera, Takamitsu; Kurosawa, Seiichi*; Kibe, Satoshi*
no journal, ,
no abstracts in English
Iijima, Kazuki; Kurosawa, Seiichi*; Tobita, Minoru*; Kibe, Satoshi*; Ouchi, Yuji*
no journal, ,
Diffusion behavior of humic acid in compacted bentonite was investigated by through-diffusion method. Concentration profile and molecular weight distribution of humic acid in the compacted bentonite indicate that only low molecular weight fraction of humic acid is likely to diffuses. Difference of diffusion behavior arising from difference of molecular weight is considered to be taken into account in evaluation of diffusion parameters.
Iijima, Kazuki; Kurosawa, Seiichi*; Kibe, Satoshi*; Tobita, Minoru*; Ouchi, Yuji*
no journal, ,
Diffusion behavior of humic acid and Nd in the presence of humic acid was investigated and modeled. Breakthrough of humic acid is observed in 0.1 and 1M NaCl with 1.2-1.6 Mg/m dry density of compacted bentonite. The presence of humic acid facilitates the migration of Nd. Diffusion Parameters were evaluated from experimental results using the one dimensional diffusion model in which migration of several Nd species with different diffusion behaviors keeping equilibrium in parallel was taken into account. Obtained diffusion parameters for humic acid and Nd will be used for prediction of diffusion behavior of radionuclides in the presence of humic acid under various conditions.
Ishii, Yasuo; Seida, Yoshimi*; Tachi, Yukio; Okazaki, Mitsuhiro*; Kurosawa, Seiichi*
no journal, ,
We developed the Sorption/diffusion data acquisition method for high sorbing nuclides using trivalent actinide Am.
Ishidera, Takamitsu; Kurosawa, Seiichi*; Kibe, Satoshi*; Ouchi, Yuji*
no journal, ,
no abstracts in English
Ito, Mitsuo; Fukaya, Hiroyuki; Ueno, Takashi; Miyata, Seiichi; Sonoda, Takashi; Usami, Hidehiko; Sakazume, Yoshinori; Kurosawa, Tatsuya; Kawasaki, Yasushi; Inagawa, Jun; et al.
no journal, ,
no abstracts in English
Ishii, Yasuo; Takahashi, Hiroaki; Seida, Yoshimi*; Tachi, Yukio; Nakazawa, Toshiyuki*; Kurosawa, Seiichi*; Okazaki, Mitsuhiro*
no journal, ,
We have developed Sorption/Diffusion Data Acquisition Method for High Sorbiong Am and Th in Horonobe Sedimentary Rock.
Ishidera, Takamitsu; Kurosawa, Seiichi*; Otsuka, Shunji*; Hayashi, Masanori*; Uchikoshi, Keiji*; Suzuki, Yasuyuki*
no journal, ,
no abstracts in English
Ishidera, Takamitsu; Kurosawa, Seiichi*; Hayashi, Masanori*; Suzuki, Yasuyuki*
no journal, ,
In the geological disposal of high-level radioactive waste (HLW) in Japan, potential impact of bentonite colloid on the migration of radionuclides needs to be evaluated in the performance assessment of geological disposal. Japan Atomic Energy Agency (JAEA) has been investigating sorption behavior of radionuclides on bentonite colloid and developing the evaluation model for the radionuclide sorption behavior on bentonite colloid. In our previous studies, the sorption behavior of Cs and Am on bentonite colloid was well interpreted by the evaluation model based on a previously reported sorption model for non-colloidal bentonite. In the presentation, the evaluation model for distribution coefficient of radionuclides sorption on bentonite colloid will be introduced in detail and the application result of evaluation model to the sorption behavior of Np on bentonite colloid will be shown.
Ishidera, Takamitsu; Kurosawa, Seiichi*; Otsuka, Shunji*; Uchikoshi, Keiji*; Kamei, Gento; Alexander, W. R.*
no journal, ,
no abstracts in English
Nakata, Kotaro*; Ishidera, Takamitsu; Kurosawa, Seiichi*; Hayashi, Masanori*; Beppu, Hikari*; Sukegawa, Akihiro*
no journal, ,
no abstracts in English
Nakata, Kotaro*; Ishidera, Takamitsu; Kurosawa, Seiichi*; Hayashi, Masanori*; Beppu, Hikari*; Sukegawa, Akihiro*
no journal, ,
no abstracts in English