An intestinal perfusion technique has been used to investigate the mechanism of action of the laxative, dioctyl sodium sulphosuccinate, in the human jejunum. Dioctyl sodium sulphosuccinate stimulated net secretion of water, sodium, chloride and potassium and inhibited net absorption of glucose and bicarbonate. These changes in water and solute transport were partially reversed by administration...

The issue of the transport of dissolved nutrients and contaminants between the sediment in the bottom of a lake or reservoir and the body of water above it is an important one for many reasons. In particular the biological and chemical condition of the body of water is intricately linked to these mass transport processes. As the review by Boudreau (Rev Geophys 38(3):389–416, 2000) clearly demon...

Solute transport in soils is commonly simulated with the advective-dispersive equation, or ADE. It has been reported that this model cannot take into account several important features of solute movement through soil. Recently, a new model has been suggested that results in a solute transport equation with fractional spatial derivatives, or FADE. We have assembled a database on published solute...

Richards and his group showed, about 40 yr ago, that the blood is filtered in the glomerulus. The largest portion of the water and solutes of the filtered fluid is absorbed across the proximal tubular wall, toward the peritubular blood capillaries (see 17). Thus, proximal tubular absorption is a process of paramount importance in the maintenance of homeostasis (1, 16). I shall review here studi...

Brackish-water reverse osmosis (BWRO) desalination facilities are designed to treat feedwater within a fixed range in salinity. If the salinity and ion concentrations of rises above maximum design concentrations, then plant may ultimately fail. BWRO plants typically use groundwater as source. Prior process design, detailed assessment is made characterize source aquifer system develop solute-tra...

Mathematical models for transport in layered media are important for investigating how restricting layers affect rates of solute migration in soil profiles; they may also improve the analysis of solute displacement experiments. This study reports an (approximate) analytical solution for solute transport during steady-state flow in a two-layer medium requiring continuity of solute fluxes and res...

advection-diffusion equation and its related analytical solutions have gained wide applications in different areas. compared with numerical solutions, the analytical solutions benefit from some advantages. as such, many analytical solutions have been presented for the advection-diffusion equation. the difference between these solutions is mainly in the type of boundary conditions, e.g. time pat...

soil water retention curve (swrc) is important in the studies of soil and water relationship, soil conservation, irrigation scheduling, drainage, solute transport, plant growth and crop water stress. the performance of 10 models (simons et al., libardy et al., campbell, farrell and larson, van genuchten, brooks and corey, driessen, exponential bruce-luxmore, power bruce-luxmore, and rogowski) w...

determination of the best method to estimate the dispersion rate is very important to ensure accuracy of the computed data. the aim of this research is studying of transport length effects of dispersion of conservative tracer nacl in soils with different texture using several solute transport models including brigham, fried-combernous and solutions of the advection-dispersion equation with inve...

Title: Modeling Sediment-Controlled TMDLs for the Branched and Braided Networks of Waterways in Louisiana: Model Development and Application to the Amite River Basin Project Number: 2005LA31B Start Date: 3/1/2005 End Date: 2/28/2006 Funding Source: 104B Congressional District: 6 Research Category: Engineering Focus Category: Models, Solute Transport, Water Quality Descriptors: None Principal In...