Hydrodynamic dispersion is an important factor controlling contaminant migration in the subsurface environment. However, few comprehensive data sets exist for critically evaluating the impact of travel distance and site heterogeneity on solute dispersion. Therefore, a series of field-scale experiments using tritiated water (H2O), and bromide (Br) as tracers was conducted on the U.S. Department ...

Expansion of human activities causes dispersion of pollutants in the subsurface environment. The fate and movement of dissolved substances in soils and groundwater has generated considerable interest out of concern for the quality of the subsurface environment. Many analytical solutions for partial differential equations exist in soil science. Numerical solutions are more general, and often mor...

The general expressions for the time-dependent ensemble averages of the second spatial moments ^A& and the effective dispersivities g, defined as (1/ 2m)(d^A&/dt) where m is the magnitude of the mean flow velocity m, are evaluated in order to study the effect of initial plume size on ^A& and g in three-dimensional heterogeneous isotropic aquifers under the first-order approximation to the parti...

The hierarchical MoS2/CoNi composites were successfully synthesized by a two-step hydrothermal method. large surface area of the MoS2 enhances dispersivity CoNi nanoparticles and formation abundant interfaces, which make an important contribution to dielectric loss, introduction improves impedance matching introduces magnetic can improve absorption performance electromagnetic waves. Through cal...