JOPSS - Search Results

Journal Articles

Concentration fluctuations in polymer gel investigated by neutron scattering; Static inhomogeneity in swollen gel

Koizumi, Satoshi; Monkenbusch, M.*; Richter, D.*; Schwahn, D.*; Farago, B.*

Journal of Chemical Physics, 121(24), p.12721 - 12731, 2004/12

https://doi.org/10.1063/1.1823411

Times Cited Count：56 Percentile：85.93(Chemistry, Physical)

no abstracts in English

JAEA Reports

Theoretical background and user's manual for the computer code on groundwater flow and radionuclide transport calculation in porous rock

JNC TN8400 2001-027, 131 Pages, 2001/11

JNC-TN8400-2001-027.pdf:0.8MB

In order to document a basic manual about input data, output data, execution of computer code on groundwater flow and radionuclide transport calculation in heterogeneous porous rock, we investigated the theoretical background about geostastical computer codes and the user's manual for the computer code on groundwater flow and radionuclide transport which calculates water flow in three dimension, the path of moving radionuclide, and one dimensional radionuclide migration. In this report, based on above investigation we describe the geostastical background about simulating heterogeneous permeability field. And we describe construction of files, input and output data, a example of calculating of the programs which simulates heterogeneous permeability field, and calculates groundwater flow and radionuclide transport. Therefore, we can document a manual by investigating the theoretical background about geostastical computer codes and the user's manual for the computer code on groundwater flow and radionuclide transport calculation. And we can model heterogeneous porous rock and analyze groundwater flow and radionuclide transport by utilizing the information from this report.

JAEA Reports

Nuclide migration uncertainty study in channel network model approximation

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JNC TN8400 2001-010, 25 Pages, 2001/03

JNC-TN8400-2001-010.pdf:4.4MB

Performance assessment in geosphere for the JNC's 2nd progress report was based on nuclide migration calculation results by discrete fracture network model. The channel network model approximated from fracture network model with considering fracture connectivity was applied for nuclide migration analysis, since fracture network model had too large data to calculate nuclide migration. However, there are many options in the process of approximation from fracture network model to channel network model. In case of analyzing nuclide migration for above report, so-called "base case", one option was chosen from many options, arbitrarily. In this report, the sensitivity of these options to nuclide migration calculation results was studied. As a result, there was no significant impact to nuclide migration although connectivity of channel and flow characteristics of the model slightly changed among different options. Based on above studies, we concluded that an option used for the base case was appropriate.

JAEA Reports

Reliability evaluation of simulation models for nearfield groundwater flow and radionuclide transport computation

*; *; *; *

JNC TJ8400 2000-006, 232 Pages, 2000/05

JNC-TJ8400-2000-006.pdf:7.75MB

In this research, simulations with some parameters which characterize ground water flow and the reliability evaluation for the expansion of the calculation method of groundwater flow were carried out by using the radionuclide transport computations in nearfield heterogeneous porous media. Concretely contents are follows: (1)With the series of calculation method for three-dimensional saturated/unsaturated groundwater flow and one-dimensional radionuclide transport. the computational analyses with the parameters used in JNC report in 2000 was carried out and the influence of the different input flux was evaluated. (2)The examination of the application for the different ways of inverse laplace transformation which is used in one-dimensional radionuclide tansport analysis code "MATRICS" was carried out. (3)The examination of the application of multi-element "MATRICS" (m-MATRICS) for radionuclide transport computations in nearfield heterogeneous porous media was carried out. (4)The series of calculation methods from three-dimensional saturated/unsaturated ground water flow simulation code to one-dimensional radionuclide transport simulation code was integrated.

JAEA Reports

None

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JNC TJ7440 2000-004, 52 Pages, 2000/03

JNC-TJ7440-2000-004.pdf:12.62MB

no abstracts in English

JAEA Reports

None

JNC TJ7420 2000-007, 28 Pages, 2000/03

JNC-TJ7420-2000-007.pdf:11.92MB

no abstracts in English

JAEA Reports

Migration behavior of actinide colloids in near-field

Nagasaki, Shinya*

JNC TJ8400 2000-004, 32 Pages, 2000/02

JNC-TJ8400-2000-004.pdf:0.69MB

Equilibrium and kinetics of sorption of NpO $_{2}^{+}$ on illite were investigated at pH = 6 by using the differential pulse anodic stripping voltammetry method and the spectroscopic method, respectively. It was found that the sorption isotherm obtained was fitted better by the Langmuir-Freundlich type equation than by the Langmuir equation. The heterogeneity coefficient was 0.89 0.05 and the half width at half maximum (HWHM) of affinity spectrum was 0.19 log unit, indicating that the surfacc of illite used has a low degree of heterogeneity. The kinetic spectra indicated that the sorption of NpO $_{2}^{+}$ occurs only at the outer surfacc. The mean HWHM of the kinetic spectra was 0.18 log unit. This also proves that the sorption kinetics of NpO $_{2}^{+}$ on the illite used is controlled by the same heterogeneity of the sorption sites. From the dependence of mean rate constants on temperature, a mean apparent activation enthalpy and a mean apparent activation entropy were evaluated at 373 kJ/mol and - 69 7 J/Kmol, respectively. This value of enthalpy suggests that the sorption is not controlled by diffusion through the hydrodynamic film around the illite. Equilibrium and kinetics of sorption of NpO $_{2}^{+}$ and Np(V) carbonate complexes (mainly NpO $_{2}$ CO $_{3}$ ) on Na-montmorillonite were also examined by using same technique.