In this study, we measure effective diffusion coefficients for trichloroethene in undisturbed soil samples taken from Picatinny Arsenal, New Jersey. The measured effective diffusion coefficients ranged from 0.0053 to 0.0609 cm2/s over a range of air-filled porosity of 0.23-0.49. The experimental data were compared to several previously published relations that predict diffusion coefficients as ...

Red blood cell (RBC) migration effects and RBC-plasma interactions occurring in microvessel blood flow have been investigated numerically using a shear-induced particle migration model. The mathematical model is based on the momentum and continuity equations for the suspension flow and a constitutive equation accounting for the effects of shear-induced RBC migration in concentrated suspensions....

The patterns of spatial and temporal variability in CO2 CH4 emission from reservoirs are still poorly studied, especially tropical regions where hydropower is growing. We performed spatially resolved measurements dissolved surface water concentrations their gas-exchange coefficients (k) to compute diffusive carbon flux four contrasting across Brazil during different hydrological seasons. used a...

An exhaustive study of the distribution of butyltin species was conducted in the sediment of the Saguenay Fjord (Canada), a semi-enclosed marine system with sediment permanently submitted to sub-Arctic cold conditions. Concentrations of total butyltins (tributyltin [TBT], dibutyltin, and monobutyltin) ranged from 6 to 288 ng Sn/g dry weight and were typical of those reported for contaminated co...

-The ratio of the fluxes of heat and salt across a diffusive interface is investigated on the premise that there are two contributions to the flux of each component. These contributions arise from the two transport mechanisms which can operate at a diffusive interface, viz. double-diffusive convection and turbulent entrainment. Estimates of the fluxes are provided for each process, and their co...

The transport of a condensing passive scalar is studied as a prototype model for the kinematics of moisture transport on isentropic surfaces. Condensation occurs whenever the scalar concentration exceeds a specified local saturation value. Since condensation rates are strongly nonlinear functions of moisture content, the mean moisture flux is generally not diffusive. To relate the mean moisture...

The geomorphic behavior of a soil-mantled hillslope undergoing diffusive creep involves a coupling between changes in land surface elevation, soil transport rates, soil production, and soil thickness. A linear stability analysis suggests that the coupled response of the soil mantle to small perturbations in soil thickness or surface topography is influenced by two factors. The diffusive-like be...