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Dohi, Terumi; Iijima, Kazuki; Machida, Masahiko; Suno, Hiroya*; Omura, Yoshihito*; Fujiwara, Kenso; Kimura, Shigeru*; Kanno, Futoshi*
Environmental radiochemical analysis VII, p.50 - 57, 2023/12
microscale localisation observationDohi, Terumi; Iijima, Kazuki; Machida, Masahiko; Suno, Hiroya*; Omura, Yoshihito*; Fujiwara, Kenso; Kimura, Shigeru*; Kanno, Futoshi*
PLOS ONE (Internet), 17(7), p.e0271035_1 - e0271035_21, 2022/07
Times Cited Count：1 Percentile：14.8(Multidisciplinary Sciences)Matsumoto, Kazuhiro*; Tanai, Kenji; Kanno, Takeshi*; Iwata, Yumiko*
JNC TN8400 2005-009, 40 Pages, 2005/06
The buffer that will be used as a component of the engineered barriers system swells when saturated by groundwater. As a result of this swelling, buffer may penetrate into the peripheral rock zone surrounding the buffer through open fractures. It sustained for extremely long periods of time, the buffer extrusion could lead to reduction of buffer density, which may in turn degrade the assumed performance. In this report, the viscosity of bentonite was measured as one of the parameter of diffusion model. In addition, the simulation analysis was carried out to confirm the applicability of diffusion model. Moreover, an analytical evaluation on extrusion behavior of buffer into rock fractures was performed due to estimate the long-term stability of buffer as reduction of density.
Tochigi, Yoshikatsu*; Kanno, Takeshi*; Ueno, Shunichiro*; Kubota, Nobuhiko*; Nishino, Junnya*; Fukunaga, Sakae*
JNC TJ7400 2005-017, 49 Pages, 2004/03
JNC-TJ7400-2005-017.PDF:12.08MB
The analytical procedure is investigated and examined with the aim of considering complex stability constant concerned with abundance ratio of metal ion / organic complexes dissolved in groundwater. The condenser of organic material in groundwater and experimental system for simulating subsurface environment are constructed and the experiment.
Kanno, Takeshi*; Iwata, Yumiko*
JNC TJ8400 2003-083, 65 Pages, 2004/02
JNC-TJ8400-2003-083.pdf:0.81MB
Modelling study on the extrusion phenomenon of the bentonite in a geological repository for the high-level radioactive is performed to enhance the reliability of latest model studied on fiscal year 2003(H14), on the matter of density distribution of extruded bentonite gel. In this study, the model is reconsidered and revised based on the result of comparison between experimental and calculated results. The numerical analyses for BENTFLOW type experiments and model experiments on extrusion in a pipe are performed using the revised model. The analyses for the BENTFLOW about distribution of extrusion density reproduce the experimental results tolerably. The agreement between the calculated and experimental results of the model experiments are not good. Our model is originated in solid diffusion model of swelling clay proposed by Nakano et al. To enhance the reliability of our model, the latest model is reviewed by experts. At last, the numerical analyses for H12 type repository are performed by revised model to evaluate the long-term reduction of bentonite density for the extrusion phenomenon. The analytical results are compared with the results described in H12 report.
Fukunaga, Sakae*; Iwata, Yumiko*; Kanno, Takeshi*; Kudo, Akira*
JNC TJ8400 2003-070, 45 Pages, 2003/02
JNC-TJ8400-2003-070.pdf:0.13MB
This report summarizes two investigations concerned with microbial influence in geological disposal facilities. 1)Literature survey on simulation models for the microbial-influence evaluation, 2) Experiment for the interaction between bacteria and Pu at Eh=-135mV.
Fukunaga, Sakae*; Iwata, Yumiko*; Kanno, Takeshi*; Kudo, Akira*
JNC TJ8400 2003-069, 73 Pages, 2003/02
JNC-TJ8400-2003-069.pdf:0.39MB
This report summarizes two investigations concerned with microbial influence in geological disposal facilities. 1)Literature surevey on simulation models for the microbial-influence evaluation. 2)Interaction between Sulfate reducing bacteria(SRB) and Pu. For simulation models, we found some papers on gas production, geochemistry, microbial corrosion and microbial amount. To make the microbial-influence evaluation more reliable, it will be necessary to study subjects such as biodegradability of organic matter, microbial amount and certification of models. The sorption experiment for Pu onto SRB was conducted. It resulted in that effects of sterilization on the distribution coefficientat were not evident at Eh=-135mV.
Kanno, Takeshi*; Iwata, Yumiko*
JNC TJ8400 2003-026, 63 Pages, 2003/02
JNC-TJ8400-2003-026.pdf:0.56MB
Modelling study on the extrusion phenomenon in a geological repository for the high-level radioactive is performed to enhance the reliability of existing model described in H12 report. Main conclusions of this study are as follows: (1) The methods and pysical interpretation of bentonite gel viscosity measurements are clarified and input data of the viscosity for the solid diffusivity are obtained. (2) The input data of the swelling pressure and hydraulic conductivity of bentonite in the low- density region necessary for the solid diffusivity are determined. (3) The consolidation-type model proposed by Ahn et al. is surveyed and compared with that used in this study. The consolidation-type model is thought to be equivalent to the solid diffusion model used in this study. (4) The numerical analyses for BENTFLOW experiments and model experiments on extrusion in a pipe are performed. The analyses for the BENTFLOW reproduce the experimental results better than the past studies. The agreement between the calculated and experimental results of the model experiments is not good. Thus further study is required for the evaluation of density distribution in extruding bentonite gel.
Fukunaga, Sakae*; Nakayama, Mamoru*; Jintoku, Takashi*; *; Kudo, Akira*
JNC TJ8400 2002-037, 68 Pages, 2002/02
JNC-TJ8400-2002-037.pdf:0.28MB
We conducted the following four investigations concerned with microbial influence in geological disposal facilities. (1)Improvement of the FEP dictionary and investigation on chemical evolution of nitrate by microbes. (2)Experimental estimation of microbial mobility in compacted Na bentonite saturated by synthetic seawater with 30wt% silica sand and Ca bentonite with 30wt% silica sand. (Both dry densities are 1.6 g/cm
.) (3)Habitation of microbes in Na rich bentonite deposit and Ca rich one. (4)Interaction between SRB (sulfate reducing bacteria) and Np in a reducing environment at Eh=-85mV. As the result, it was revealed that (1)microbial activity in near field rock and microbial denitrification of nitrate under the existence of electron donor are important, (2)microbes didn't move in Na bentonite in 3 weeks and moved to the distance of 20mm in Ca bentonite, and (3)microoragnisms existed at the inside of the deposits. (4) The difference between distribution coefficient of Eh=-85mV and Eh=-500mV was evaluated.
Sugino, Hiroyuki; *
JNC TN8400 99-040, 75 Pages, 1999/11
The buffer material that will be buried as a component of the engineered barriers system swells when saturation by groundwater. As a result of this swelling, buffer material may penetrate into the peripheral rock zone surrounding the buffer through open fractures. If sustained for extremely in long-period of time, The buffer material extrusion could lead to reduction of buffer density, which may in turn degrade the assumed performance assessment properties (e.g., permeability, diffusion coefficient) JNC has been conducted the study of bentonite extrusion into fractures of rock mass as a part of high level waste research. In 1997, JNC has reported the test results concerning buffer material extrusion and buffer material erosion. These tests have been done using test facilities in Geological Isolation Basic Research Facility. After 1997, JNC also conducted analytical study of buffer material extrusion. This report describes the analysis results of this study which are reflected to the H12 report. In this analysis, The diffusion coefficient was derived as a function of the swelling pressure and the viscosity resistance of the buffer materials. Thus, the reduction in density of buffer materials after emplacement in saturated rock was assessed. The assessment was made assuming parallel-plate radial fractures initially filled by water only. Because fractures in natural rock masses inevitably have mineral inclusions inside of them and fractures orientation leads to fractures intersecting other fractures, this analysis gives significantly conservative conditions with respect to long-term extrusion of buffer and possible decrease in buffer density.
Ishikawa, Hirohisa; Kanno, Takeshi; Matsumoto, Kazuhiro*
PNC TN8410 97-313, 32 Pages, 1997/09
None
Matsumoto, Kazuhiro*; Kanno, Takeshi; Fujita, Tomoo; Suzuki, Hideaki*
PNC TN8410 97-296, 134 Pages, 1997/04
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; Kanno, Takeshi; Ishikawa, Hirohisa; Ishiguro, Katsuhiko
PNC TN8410 97-074, 60 Pages, 1997/02
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; Kanno, Takeshi; Ishikawa, Hirohisa; Ishiguro, Katsuhiko
PNC TN8410 97-051, 53 Pages, 1997/02
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Chijimatsu, Masakazu*; Matsumoto, Kazuhiro*; Kanno, Takeshi; Ishiguro, Katsuhiko; Sugita, Yutaka; Moro, Yoshiji*; Ishikawa, Hirohisa
PNC TN8410 97-025, 57 Pages, 1997/01
None
Taniguchi, Wataru; Fujita, Tomoo; Kanno, Takeshi; Ishikawa, Hirohisa;
Proceedings of 8th International Topical Meeting on Nuclear Reactor Thermal-Hydraulics (NURETH-8), 0 Pages, 1997/00
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