Time domain reflectometry (TDR) is rapidly becoming a popular method for measuring solute concentrations in the laboratory as well as in the field. Success or failure of TDR to represent solute resident concentrations depends on the accuracy of the invoked calibration. In this study, we compared three commonly used calibration methods that relate the impedance, Z+ as measured with TDR, to the s...

A stream solute workshop was held February 1-5,1989, at The University of Mississippi with the goals of 1) suggesting a conceptual model for stream solute studies that integrates physical, chemical, and biological processes, and 2) identifying advantages and limitations of various methods for studying solute transport and exchanges. Solute dynamics refers to the spatial and temporal patterns of...

A theoretical study is presented of the effect of a radially converging melt flow, which is directed away from the solidification front, on the radial solute segregation in simple solidification models. We show that the classical Burton-Prim-Slichter (BPS) solution describing the effect of a diverging flow on the solute incorporation into the solidifying material breaks down for the flows conve...

We investigate convective-diffusive transport of a solute through a medium with properties that can be externally modulated in space and time. In particular, we focus on the effect of a front-a sharp transition in the convective velocity (v) and diffusivity (D)-on the evolution of the solute concentration profile. Numerical results show that by suitably moving the front during the process an an...

Forward osmosis (FO) can be used to extract clean water and pre-concentrate municipal wastewater to make it amenable to anaerobic treatment. A protocol was developed to assess the suitability of FO draw solutes for pre-concentrating wastewater for potential integration with anaerobic treatment to facilitate resource recovery from wastewater. Draw solutes were evaluated in terms of their ability...

Cell volume and concentration regulation in the presence of changing extracellular environments has been studied for centuries, and recently a general nondimensional model was introduced that encompassed solute and solvent transmembrane flux for a wide variety of solutes and flux mechanisms. Moreover, in many biological applications it is of considerable interest to understand optimal controls ...

A finite element formulation of neutral solute transport across a contact interface between deformable porous media is implemented and validated against analytical solutions. By reducing the integral statements of external virtual work on the two contacting surfaces into a single contact integral, the algorithm automatically enforces continuity of solute molar flux across the contact interface,...

The experimentally observed steady-level distribution of Na+ (25 degrees) and of D-glucose (0 degree c) in frog muscle were chosen as examples of solute distribution patterns observed in living cells, for comparison with those predicted by two theoretical models: one derived from the membrane-pump theory and the other from the association-induction (AI) hypothesis. Neither the distribution of N...

In this study, we introduce a numerical method to reduce the solute transport equation into a reduced form that can replicate the behavior of the model described by the original equation. The basic idea is to collect an ensemble of data of state variables (say, solute concentration), called snapshots, by running the original model, and then use the proper orthogonal decomposition (POD) techniqu...