Results 181 to 190 of about 1,224,440 (219)

Vertical migration of radionuclides in undisturbed grassland soils

Journal of Environmental Radioactivity, 2009
Literature data on numerical values obtained for the parameters of the two most popular models for simulating the migration of radionuclides in undisturbed soils have been compiled and evaluated statistically. Due to restrictions on the applicability of compartmental models, the convection-dispersion equation and its parameter values should be ...
Gerald, Kirchner, Friederike, Strebl, Peter, Bossew, Sabine, Ehlken, Martin H, Gerzabek   +4 more
openaire   +2 more sources

Migration of Radionuclide Chains in Groundwater

Nuclear Technology, 1978
Expressions are developed for the maximum concentrations and discharge rates of radioactive nuclide chains migrating through an adsorbing medium. These expressions are presented in terms of nondimensional parameters. Conditions are established that quantify the reconcentration effort of radionuclide chain migration in terms of the nondimensional ...
openaire   +1 more source

Mathematical modelling of radionuclide migration in groundwater

Quarterly Journal of Engineering Geology, 1986
Summary This paper reviews recent work on the development of mathematical models for the transport of radionuclides in flowing groundwater. These models have an important role to play in assessing the long-term safety of radioactive waste burial, and in the planning and interpretation of associated experiments.
A. W. Herbert, D. P. Hodgkinson, D. A. Lever, J. Rae, P. C. Robinson   +4 more
openaire   +1 more source

Chemical speciation of radionuclides migrating in groundwaters

Journal of Radioanalytical and Nuclear Chemistry Articles, 1995
In order to more accurately predict the rates and mechanisms of radionuclide migration from lowlevel waste disposal facilities via groundwater transport, ongoing studies are being conducted at field sites at Chalk River Laboratories to identify and characterize the chemical speciation of mobile, long-lived radionuclides migrating in groundwaters. Large-
D. E. Robertson, A. J. Schilk, K. H. Abel, E. A. Lepel, C. W. Thomas, S. L. Pratt, E. L. Cooper, P. Hartwig, R. W. D. Killey   +8 more
openaire   +1 more source

Clay as a barrier to radionuclide migration

Progress in Nuclear Energy, 1987
Abstract Because of their low permeability, high sorption capacity and plasticity clay bodies are potentially suitable repositories for radioactive waste. This paper discusses the factors that influence radionuclide mobility in natural clay materials. Methods for determining radionuclide migration rates are described and compared.
openaire   +1 more source

Migration studies of radionuclides in boom clay

Engineering Geology, 1985
Abstract Sorption results obtained with Boom clay for Am, Pu, Eu, Tc and Np under near in-situ conditions are presented, and the significance ofKd values in Boom clay is discussed. Clay humic acids are shown to be a controlling factor in the sorption of Am, Eu, Np. Results with Tc and Pu are different and need further examination.
P.N. Henrion, M. Monsecour, M. Put
openaire   +1 more source

Modelling of migration of leached radionuclides by groundwater

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1986
Abstract Radionuclides may be carried by groundwater from an underground waste repository to places accessible to man. The central role of mathematical modelling is to predict how their concentration varies in time at positions around the repository.
J. Rae, J. H. Black
openaire   +1 more source

Migration of Radionuclide Chains In Subseabed Disposal

MRS Proceedings, 1981
ABSTRACTIn this study of subseabed disposal, the two dimensional (axial and radial) migration of radionuclide chains released from a canister located in a sedimentary layer bounded at the top by the ocean and at the bottom by an impermeable basalt zone is analyzed to determine the escape rate of radlonuclides into the seawater.
A. K. Ray, H. E. Nuttall
openaire   +1 more source

The Influence of Speciation on the Geospheric Migration of Radionuclides

Nuclear Technology, 1982
Radionuclides in ground water can exist as different species whose retention factors may be strongly different. For one-dimensional transport in a porous medium, conditions for the existence of equilibrium between two species are given. In most cases, these conditions are probably well fulfilled when time scales of geosphere transport are considered ...
openaire   +2 more sources

Uncertainty and sensitivity analysis of radionuclide migration through fractured granite aquifer

Journal of Environmental Radioactivity, 2022
Zhenxue Dai, Zhijie Yang, Zhengyang Du   +2 more
exaly