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JAEA Reports

Studies on Data Base Management for Nuclide Migration and Improvement of Individual Models (II) (Summary)

Tsujimoto, Keiichi*; Miura, Fusae*; Morooka, Koichi*; Ueta, Shinzo*

JNC TJ8400 2004-021, 75 Pages, 2005/02

JNC-TJ8400-2004-021.pdf:1.31MB

Methods of management of database which was based on understanding of phenomena, reliable, and closely related with performance assessment were studied on parallel with researches for individual model improvement by means of literature survey, column experiment, and analysis code development.For future management of JNC-TDB was discussed with the latest literatures. Collaboration with outer organization was considered necessary especially on authorization of the TDB. One of the outer organizations could be found in geo-thermal research field.For future management of JNC-SDB, sorption ithotherm of Np on bentonite was tested, and the consistency of the data in SDB was found. A semi-quantitative evaluation method of the reliability of the data was developed and tested with the sorption of Pu and Ni on bentonite. The result shows moderateness of the method and some literature data was considered unreliable by the evaluation.From the literature survey of ir/reversibility of nuclide sorption on colloid showed that apparent irreversibility may often be caused by slow kinetics. Additionally, some general recommendation on the system to be studied was discussed.The column experiment of Sr migration facilitated by colloid through porous media was carried out and analysed by COLFRAC-MRL code. The code was developed to simulate the colloid facilitated migration through porous media.

JAEA Reports

Studies on Data Base Management for Nuclide Migration and Improvement of Individual Models (II)

Tsujimoto, Keiichi*; Miura, Fusae*; Morooka, Koichi*; Ueta, Shinzo*

JNC TJ8400 2004-020, 294 Pages, 2005/02

JNC-TJ8400-2004-020.pdf:3.96MB

Methods of management of database which was based on understanding of phenomena, reliable, and closely related with performance assessment were studied on parallel with researches for individual model improvement by means of column experiment, and analysis code development for colloids.For nuclide transport database, the basic data development method was examined in order to improve the credibility of the data stored in the database.For the analysis and code development for colloid transport, user interface of the colloid transport analysis code, COLFRAC-MRL code, that was developed in the last year, was developed. The dose analysis based on the nuclide transport analysis with considering colloids are executed by using COLFRAC-MRL code. The effect of chemical equilibrium and kinetics model for nuclide sorption on colloids are evaluated in the analysis.The standard measurement method was examined and data was obtained by the experiments for distribution coefficient of nuclide and colloids, which is the important parameter for safety performance assessment of high-level radioactive waste.

Journal Articles

Effects of Kinetic Radionuclide Sorption onto Colloids for Radionuclide Transport in Fractured Rock; Experimental and Numerical Studies

Kurosawa, Susumi; Ibaraki, Motomu*; Yui, Mikazu; Ueta, Shinzo*; Yoshikawa, Hideki

Nihon Genshiryoku Gakkai Wabun Rombunshi, 3(3), p.249 - 256, 2004/09

Colloidal effect is one of the major factors to enhance the transport of radionuclide in groundwater. In this study, the impact of kinetic reactions of radionuclide sorption onto both the fracture wall and colloid on the transport behavior of radionuclide were investigated by carrying out the transport experiment of the radionuclide with colloid through fractured rock. In the experiments, the Cs and clay colloid were used as moderately sorbing radionuclide and typical natural colloid by the concentration of 1.0$$times$$10$$^{-6}$$ g/l (7.5$$times$$10$$^{-9}$$ mol/l) and 3.5$$times$$10$$^{-3}$$ g/l, respectively. The granodiorite with artificially the single fracture (dimension: 50$$times$$50$$times$$0.5 mm) was used. The results of the transport experiments were analyzed by numerical simulation code of radionuclide transport COLFRAC which can model radionuclide transport based on either equilibrium or kinetic reaction of radionuclide sorption onto fracture wall and colloid. Consequently, it was indicated that calculated results strongly dep

JAEA Reports

Evaluation in an Effect of Microorganism on Performance Assessment by COLFRAC

Kurosawa, Susumi; Sasaki, Ryoichi; Ueta, Shinzo*; Yoshikawa, Hideki

JNC TN8400 2004-012, 68 Pages, 2004/07

JNC-TN8400-2004-012.pdf:5.37MB

In order to evaluate the impact of microorganism by COLFRAC, which simulates colloid-facilitated contaminant migration, the microorganism - radionuclide sorption data and microbial films data in deep geological environment were surveyed. After the survey, the data conversion to be able to calculate the effect of them on performance assessment in COLFRAC has been undertaken. As the results of calculation by COLFRAC, the transport behavior of radionuclide may be enhanced, when radionuclide will be taken in the microorganism. Furthermore, the results indicated that the transport rate of radionuclide depends on microbial concentration.

JAEA Reports

Development of JNC Geological Disposal Technical Information Integration System for Geological Environment Field

Tsuchiya, Makoto*; Ueta, Shinzo*; Ohashi, Toyo*

JNC TJ8440 2004-006, 341 Pages, 2004/02

JNC-TJ8440-2004-006.pdf:7.99MB

Enormous data on geology, geological structure, hydrology, geochemistry and rock properties should be obtained by various investigation/study in the geological disposal study. Therefore, "JNC Geological Disposal Technical Information Integration System for Geological Environment Field" was developed in order to manage these data systematically and to support/promote the use of these data for the investigators concerned. The system is equipped with database to store the information of the works and the background information of the assumptions built up in the works on each stage of data flow ("investigation" $$rightarrow$$ "data sampling" $$rightarrow$$ "interpretation" $$rightarrow$$ "conceptualization/modeling/simulation" $$rightarrow$$ "output") in the geological disposal study. In this system the data flow is shown as "plan" composed of "task" and "work" to be done in the geological disposal study. It is possible to input the data to the database and to refer data from the database by using GUI that shows the data flow as "plan". The system was installed to the server computer possessed by JNC and the system utilities were checked on both the server computer and client computer also possessed by JNC.

JAEA Reports

Studies on Data Base Management for Nuclide Migration and Improvement of Individual Models (Summary)

Ueta, Shinzo*; Kuno, Yoshio*

JNC TJ8400 2003-066, 34 Pages, 2004/02

JNC-TJ8400-2003-066.pdf:0.44MB

Methods of management of database which was based on understanding of phenomena, reliable, and closely related with performance assessment were studied on parallel with researches for individual model improvement by means of literature survey, column experiment, and analysis code development. For future management of JNC-TDB was discussed with the latest literatures. Collaboration with outer organization was considered necessary especially on authorization of the TDB. One of the outer organizations could be found in geo-thermal research field. For future management of JNC-SDB, sorption ithotherm of Np on bentonite was tested, and the consistency of the data in SDB was found. A semi-quantitative evaluation method of the reliability of the data was developed and tested with the sorption of Pu and Ni on bentonite. The result shows moderateness of the method and some literature data was considered unreliable by the evaluation. From the literature survey of ir/reversibility of nuclide sorption on colloid showed that apparent irreversibility may often be caused by slow kinetics. Additionally, some general recommendation on the system to be studied was discussed. The column experiment of Sr migration facilitated by colloid through porous media was carried out and analysed by COLFRAC-MRL code. The code was developed to simulate the colloid facilitated migration through porous media.

JAEA Reports

Studies on Data Base Management for Nuclide Migration and Improvement of Individual Models

Ueta, Shinzo*; Kuno, Yoshio*

JNC TJ8400 2003-065, 204 Pages, 2004/02

JNC-TJ8400-2003-065.pdf:2.13MB

Methods of management of database which was based on understanding of phenomena, reliable, and closely related with performance assessment were studied on parallel with researches for individual model improvement by means of literature survey, column experiment, and analysis code development. For future management of JNC-TDB was discussed with the latest literatures. Collaboration with outer organization was considered necessary especially on authorization of the TDB. One of the outer organizations could be found in geo-thermal research field. For future management of JNC-SDB, sorption ithotherm of Np on bentonite was tested, and the consistency of the data in SDB was found. A semi-quantitative evaluation method of the reliability of the data was developed and tested with the sorption of Pu and Ni on bentonite. The result shows moderateness of the method and some literature data was considered unreliable by the evaluation. From the literature survey of ir/reversibility of nuclide sorption on colloid showed that apparent irreversibility may often be caused by slow kinetics. Additionally, some general recommendation on the system to be studied was discussed. The column experiment of Sr migration facilitated by colloid through porous media was carried out and analysed by COLFRAC-MRL code. The code was developed to simulate the colloid facilitated migration through porous media.

Journal Articles

Experimental and Numerical Studies on Colloid-enhanced Radionuclide Transport: The Effects of Kinetic Radionuclide Sorption onto Colloidal Particles

Kurosawa, Susumi; Yui, Mikazu; Yoshikawa, Hideki; Ibaraki, Motomu*; Ueta, Shinzo*

Abstracts P.510-511, p.510 - 511, 2004/00

Many studies have shown that colloidal particles which exist in ground water can facilitate radionuclide transport in subsurface environments. We conducted a series of laboratory experiments to investigate the effects of radionuclide sorption onto colloids and the surfaces of rock fractures. We focused on overall effects related to the kinetic behavior of those sorption processes. A mixed solution of cesium and clay colloids was injected into an artificially-created single fracture in a granite column. The fracture aperture and length are 0.5 mm and 50 cm, respectively. Numerical simulations were conducted to analyze the experiment results using a numerical code COLFRAC which can simulate colloid-facilitated solute transport in discretely-fractured porous media. The numerical formulation allows for either equilibrium or kinetic sorption onto the fracture walls, and the mobile and filtered colloidal particles. A series of experimental and numerical analyses shows that migration of cesium is facilitated by mobile colloidal particles which can sorb cesium and migrate in the fracture. The analyses also demonstrate that cesium migration is significantly enhanced if desorption of cesium from the colloids is a slow kinetic process and illustrate the importance of evaluating the parameters which describe such kinetic processes. Furthermore, radionuclide transport is likely to be retarded if mobile colloidal particles which sorb radionuclides are vigorously filtered on the fracture surfaces.

Journal Articles

Experimental and Numerical Studies on Colloid-Enhanced Radionuclide Transport; The Effect of Kinetic Radionuclide Sorption onto Colloidal Particles

Kurosawa, Susumi; Ibaraki, Motomu*; Yui, Mikazu; Ueta, Shinzo*; Yoshikawa, Hideki

Materials Research Society Symposium Proceedings, Vol.824, 473 Pages, 2004/00

We conducted a series of laboratory experiments to investigate the effects of radionuclide sorption onto colloids and the surfaces of rock fractures. We focused on overall effects related to the kinetic behavior of those sorption processes. A mixed solution of cesium and clay colloids was injected into an artificially-created single fracture in a granite column. Numerical simulations were conducted to analyze the experiment results using a numerical code COLFRAC which can simulate colloid-facilitated solute transport in discretely-fractured porous media. A series of experimental and numerical analyses show that migration of cesium is facilitated by mobile colloidal particles which can sorb cesium and migrate in the fracture. The analyses also demonstrate that cesium migration is significantly enhanced if desorption of cesium from the colloids is a slow kinetic process and illustrate the importance of evaluating the parameters which describe such kinetic processes. Furthermore, radionuclide transport is likely to be retarded if mobile colloidal particles which sorb radionuclides are vigorously filtered on the fracture surfaces.

Journal Articles

Practical Availability of Radionuclide Transport Model based on the Interaction among Radionuclide, Colloid and Rock

Kurosawa, Susumi; Ueta, Shinzo*; Yui, Mikazu; Kato, Hiroyasu*; Hayashi, Kenichi*; *; Yoshikawa, Hideki

Nihon Genshiryoku Gakkai Wabun Rombunshi, 2(4), p.460 - 468, 2003/12

None

JAEA Reports

Transport Behavior of Colloids through Compacted Bentonite -Study with 3wt%Nacl Solution and Ca-Type Bentonite-

Kurosawa, Susumi; Kuno, Yoshio*; Morooka, Koichi; Ueta, Shinzo*

JNC TN8430 2003-006, 39 Pages, 2003/03

JNC-TN8430-2003-006.pdf:26.18MB

The transport behavior of colloids through the compacted sand-bentonite mixture was investigated by the column experiments. Colloidal gold was used to simulate the mobile colloids because gold colloid was stabilized easily. The sand-bentonite mixtures were prepared by mixing 30wt.% silica sand with the bentonite (Na-type and Ca-type) and were compacted at the dry density of 1.6g/cm$$^{3}$$. The colloidal particles in the 3.5% NaCl solution migrated through the compacted sand- Na bentonite mixture at 8kgf/cm$$^{2}$$ of injection pressure. However colloidal migration was not observed after injection pressure of the colloidal solution was lowered below the swelling pressure. And the selective flow path of colloids in the compacted sand-bentonite mixture was observed after the experiment. On the other hand, colloids in the pure water were filtered by the compacted sand- Ca bentonite mixture.

JAEA Reports

Study on the Development of Geological Environmental Model(II) -Outline-

Tsujimoto, Keiichi*; Shinohara, Yoshinori*; Saito, Shigeyuki*; Ueta, Shinzo*; Ohashi, Toyo*; Sasaki, Ryoichi*; Shingo, Tomiyama*

JNC TJ8400 2003-040, 78 Pages, 2003/02

JNC-TJ8400-2003-040.pdf:1.45MB

The safety performance assessment was carried out in imaginary geological environment in the conventional research and development of geological disposal, but the importance of safety assessment based on the repository design and considering the concrete geological environment will increase in the future. The research considering the link of the major three fields of geological disposal, investigation of geological environment, repository design and safety performance assessment, is the contemporary worldwide research theme. Hence it is important to organize information flow that contains the series if information process from the data production to analysis in the three fields, and to systemize the knowledge base that unifies the information flow hierarchically.The information flow for geological environment model generation process is examined and modified base on the product of the research of "Study on the development of geological environment model" that of the research in 2002. The work flow diagram for geological structure and hydrology are modified, and those for geochemical and rock property are examined from the search. Furthermore, database design was examined to build geochemical environment database (knowledgebase) based on the result of the systemization of the environment model generation technology. The geochemical environment database was designed and the prototype system is build to contribute database design.

JAEA Reports

Study on the Development of Geological Environmental Model(II)

Tsujimoto, Keiichi*; Shinohara, Yoshinori*; Saito, Shigeyuki*; Ueta, Shinzo*; Ohashi, Toyo*; Sasaki, Ryoichi*; Shingo, Tomiyama*

JNC TJ8400 2003-039, 395 Pages, 2003/02

JNC-TJ8400-2003-039.pdf:7.74MB

The safety performance assessment was carried out in imaginary geological environment in the conventional research and development of geological disposal, but the importance of safety assessment based on the repository design and considering the concrete geological environment will increase in the future. The research considering the link of the major three fields of geological disposal, investigation of geological environment, repository design and safety performance assessment, is the contemporary worldwide research theme. Hence it is important to organize information flow that contains the series if information process from the data production to analysis in the three fields, and to systemize the knowledge base that unifies the information flow hierarchically.The information flow for geological environment model generation process is examined and modified base on the product of the research of "Study on the development of geological environment model" that of the research in 2002. The work flow diagram for geological structure and hydrology are modified, and those for geochemical and rock property are examined from the search. Furthermore, database design was examined to build geochemical environment database (knowledgebase) based on the result of the systemization of the environment model generation technology. The geochemical environment database was designed and the prototype system is build to contribute database design.

JAEA Reports

The Study on the Characterization of Colloids in Groundwater(II)

Kuno, Yoshio*; Ueta, Shinzo*

JNC TJ8400 2003-025, 47 Pages, 2003/02

JNC-TJ8400-2003-025.pdf:1.24MB

Groundwater colloids may act as carriers for sorbing radionuclides released from a radioactive waste repository. To evaluate the influence of colloids to nuclide transport, it is necessary to obtain the characteristic data of groundwater colloids (e.g. colloid concentration, the distribution coefficient for sorption of nuclides on colloids) in the deep geological media and to prepare the simulation code of nuclide transport with colloids. In this study, the groundwater sample was collected from the gallery of the mine in crystalline rock media to investigate the population of the natural colloids. The concentration, size distribution and chemical compositions of colloids were measured by using filtration method. Colloidal particles consist mainly of silicate minerals and Ca-rich particles. The dissolved organic materials were not detected in the groundwater. The properties of colloids seem to depend on the host rock type and the groundwater chemistry. To simulate the in-situ condition of groundwater, chemical conditions were controlled by varying the partial pressure of CO$$_{2}$$ and the colloid generation in each groundwater was investigated. The numerical model (COLFRAC) is developed in Ohio state university that incorporates the mechanism of colloid-facilitated nuclide transport in fractured porous media. Both equilibrium and kinetic sorption of nuclides onto colloidal materials can be considered in this calculation code. The guidance to learn how to use this code was conducted and the user's manual was prepared.

JAEA Reports

The Study on the Characterization of Colloids in Groundwater(II)

Kuno, Yoshio*; Ueta, Shinzo*

JNC TJ8400 2003-024, 129 Pages, 2003/02

JNC-TJ8400-2003-024.pdf:2.43MB

Groundwater colloids may act as carriers for sorbing radionuclides released from a radioactive waste repository. To evaluate the influence of colloids to nuclide transport, it is necessary to obtain the characteristic data of groundwater colloids (e.g. colloid concentration, the distribution coefficient for sorption of nuclides on colloids) in the deep geological media and to prepare the simulation code of nuclide transport with colloids. In this study, the groundwater sample was collected from the gallery of the mine in crystalline rock media to investigate the population of the natural colloids. The concentration, size distribution and chemical compositions of colloids were measured by using filtration method. Colloidal particles consist mainly of silicate minerals and Ca-rich particles. The dissolved organic materials were not detected in the groundwater. The properties of colloids seem to depend on the host rock type and the groundwater chemistry. To simulate the in-situ condition of groundwater, chemical conditions were controlled by varying the partial pressure of CO$$_{2}$$ and the colloid generation in each groundwater was investigated. The numerical model (COLFRAC) is developed in Ohio state university that incorporates the mechanism of colloid-facilitated nuclide transport in fractured porous media. Both equilibrium and kinetic sorption of nuclides onto colloidal materials can be considered in this calculation code. The guidance to learn how to use this code was conducted and the user's manual was prepared.

JAEA Reports

Effect of colloid filtration by bentonite barrier altered in alkalic conditions

*; Shibata, Masahiro; Ueta, Shinzo*; *; Yui, Mikazu

JNC TN8400 2002-013, 33 Pages, 2002/03

JNC-TN8400-2002-013.pdf:1.23MB

In the construction of geological disposal repository for radioactive waste, cementitious material may be used, e.g. as a mechanical support for tunnel. Regarding such conditions, evaluation of bentonite buffer alteration by high-pH solution, which caused by groundwater-cementitious material interaction, is important. In this study, colloid filtration ability of bentonite buffer acceleratingly altered by high-pH solution was experimentally investigated. The compacted bentonite specimen were first hydrothermally treated at high-pH (pH 14 or pH 12.5, at 200$$^{circ}$$C). Then the mineralogical alteration was identified by XRD, and colloid permeability test was conducted. In the case that the specimen was treated at pH 14, serious smectite dissolution and feldspar crystallization was observed, and colloid permeation was identified. From the results of this study, the importance of understanding of alteration behavior in the actual repository condition, and examinations of the colloid filtration ability of the alteration products are highlighted.

JAEA Reports

Study on the development of geological environmental Model

Tsujimoto, Keiichi*; Shinohara, Yoshinori*; Saito, Shigeyuki*; Ueta, Shinzo*; *; *; *

JNC TJ8400 2002-030, 100 Pages, 2002/03

JNC-TJ8400-2002-030.pdf:0.98MB

The safety performance assessment was carried out in potential geological environment in the conventional research and development of geological disposal, but the importance of safety assessment based on the repository design and scenario considering the concrete geological environment will increase in the future. The research considering the link of the major three fields of geological disposal, investigation of geological environment, repository design, and safety performance assessment, is the contemporary worldwide research theme. Hence it is important to organize information flow that contains the series of information process form the data production to analysis in the three fields, and to systemize the knowledge base that unifies the information flow hierarchically. The purpose of the research is to support the development of the unified analysis system for geological disposal. The development technology for geological environmental model studied for the second progress report by JNC are organized and examined for the purpose of developing database system with considering the suitability for the deep underground research facility. The geological environmental investigation technology and building methodology for geological structure and hydro geological structure models are organized and systemized. Furthermore, the quality assurance methods in building geological environment models are examined. Information which is used and stored in the unified analysis system are examined to design database structure of the system based on the organized methodlogy for building geological environmental model. The graphic processing function for data stored in the unified database are examined. Furthermore, future research subjects for the development of detail models for geological disposal are surveyed to organize safety performance system.

JAEA Reports

Study on the development of geological environmental model

Tsujimoto, Keiichi*; Shinohara, Yoshinori*; Saito, Shigeyuki*; Ueta, Shinzo*; *; *; *

JNC TJ8400 2002-019, 480 Pages, 2002/03

JNC-TJ8400-2002-019.pdf:7.86MB

The safety performance assessment was carried out in potential geological environment in the conventional research and development of geological disposal, but the importance of safety assessment based on the repository design and scenario considering the concrete geological environment will increase in the future. The research considering the link of the major three fields of geological disposal, investigation of geological environment, repository design, and safety performance assessment, is the contemporary worldwide research theme. Hence it is important to organize information flow that contains the series of information process form the data production to analysis in the three fields, and to systemize the knowledge base that unifies the information flow hierarchically. The purpose of the research is to support the development of the unified analysis system for geological disposal. The development technology for geological environmental model studied for the second progress report by JNC are organized and examined for the purpose of developing database system with considering the suitability for the deep underground research facility. The geological environmental investigation technology and building methodology for geological structure and hydro geological structure models are organized and systemized. Furthermore, the quality assurance methods in building geological environment models are examined. Information which is used and stored in the unified analysis system are examined to design database structure of the system based on the organized methodlogy for building geological environmental model. The graphic processing function for data stored in the unified database are examined. Furthermore, future research subjects for the development of detail models for geological disposal are surveyed to organize safety performance system.

JAEA Reports

Characteristic Assessment of Colloids Present in Groundwater

Ueta, Shinzo*; *

JNC TJ8400 2001-053, 18 Pages, 2002/02

JNC-TJ8400-2001-053.pdf:0.5MB

Specific data will be collected in process which is considered essential factors of repository after make selection of predetermined repository. Examination of the role is necessary to collect for characteristic data of nature colloids in groundwater from viewpoint of safety assessment. In this study aimed at type and concentration of groundwater colloid relevant to colloid character to safety assessment, investigation of methods for collecting colloid data and verification of the methods carried out by using natural groundwater. (1)Examination on sampling and character assessment of groundwater colloids Sampling methods of groundwater were examined to collect of characteristic data on groundwater colloids at specific site. (2)Characteristic assessment of colloids in groundwater. Concentration, size distribution and chemical components of groundwater colloids were measured for characteristic assessment of colloids in groundwater. The results indicate that components of groundwater colloid depended stratum components, and ions in groundwater might form pseudocolloid by sorption to colloids. Also, in this study, distribution coefficients were measured between colloid and radionuclide. The results indicated that distribution coefficients will be depended radionuclide concentration.

JAEA Reports

Characteristic assessment of colloids present in groundwater

Ueta, Shinzo*; *

JNC TJ8400 2001-052, 55 Pages, 2002/02

JNC-TJ8400-2001-052.pdf:2.09MB

Specific data will be collected in process which is considered essential factors of repository after make selection of predetermined repository. Examination of the role is necessary to collect for characteristic data of nature colloids in groundwater from viewpoint of safety assessment. In this study aimed at type and concentration of groundwater colloid relevant to colloid character to safety assessment, investigation of methods for collecting colloid data and verification of the methods carried out by using natural groundwater. (1)Examination on sampling and character assessment of groundwater colloids Sampling methods of groundwater were examined to collect of characteristic data on groundwater colloids at specific site. (2)Characteristic assessment of colloids in groundwater. Concentration, size distribution and chemical components of groundwater colloids were measured for characteristic assessment of colloids in groundwater. The results indicate that components of groundwater colloid depended stratum components, and ions in groundwater might form pseudocolloid by sorption to colloids. Also, in this study, distribution coefficients were measured between colloid and radionuclide. The results indicated that distribution coefficients will be depended radionuclide concentration.

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