Experimental study of multicomponent diffusion in low permeable sediments

An experimental study of diffusion and convection of multicomponent gases through catalytic and non-catalytic membranes

Diffusion of binary and ternary gases through catalytic and non-catalytic membranes has been studied experimentally at atmospheric pressure. These experiments were conducted in a modified Wicke-Kallenbach diffusion cell consisting of two continuously stirred gas volumes separated by a membrane. The equipment was suitable to measure fluxes of components through the membrane in the absence of gas...

DyNAMICS AbOvE AND WIthIN PErMEAbLE SEDIMENtS

Submersible-operated porewater sampler for permeable sediments

A sampler was developed to collect porewater from permeable (sandy) sediments during manned-submersible operations. The sampler uses vacuum (or atmospheric-pressure) reservoirs to draw porewater into a sediment probe and then into inline sample loops. The sampler is relatively inexpensive, easy to construct, and selfcontained, operating without an external power supply. The sample-loop/reservoi...

Uphill diffusion in multicomponent mixtures.

Molecular diffusion is an omnipresent phenomena that is important in a wide variety of contexts in chemical, physical, and biological processes. In the majority of cases, the diffusion process can be adequately described by Fick's law that postulates a linear relationship between the flux of any species and its own concentration gradient. Most commonly, a component diffuses down the concentrati...

Multicomponent diffusion in polymeric liquids.

It is shown how the phase-space kinetic theory of polymeric liquid mixtures leads to a set of extended Maxwell-Stefan equations describing multicomponent diffusion. This expression reduces to standard results for dilute solutions and for undiluted polymers. The polymer molecules are modeled as flexible bead-spring structures. To obtain the Maxwell-Stefan equations, the usual expression for the ...