Time Development of a Liquid Junction

There has, as mentioned above, been much interest in liquid junctions for a long time. Often only a steady state is of interest, and theoretical junction potentials were derived as early as 1890 by Planck [6] and Henderson in 1907 [7], who is usually cited for his analytical solution, which serves as a standard for comparison. A table of such potentials was provided by Smyrl and Newman [47], Time-dependent 

Equations (13.6) and (13.2) are now normalised. The reference length most appropriate here is the Debye length, here defined as 

The reference diffusion coefficient D is most appropriately taken as /DaDr. This produces the new dimensionless set of pdes 

The length L must be chosen such that there are no significant changes in concentrations at X = L at the maximum time T ax to which the simulation is to be driven, that is, as usual. 

If the two diffusion coefficients differ markedly, one might, on the other hand, use 

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