Kinetische Herleitung verallgemeinerter NERNST-PLANCK-Gleichungen. III. Eindimensionales Membranmodell

In this part onedimensional models of membranesystems are treated, i.e. such membranes, which are unbounded in two dimensions y, z. The equations of motion for such systems can be derived using the results of part I or of part II. The equation of motion containing the one particle densities can be written in the form of an Onsager relation, the coefficients L_αβ of which are symmetric. The dependence of L_αβ on the densities is calculated. The approximation used up to now in the literature is seen to be the lowest order one. Global balancy equations yield the boundary conditions on surfaces of discontinuities. It is shown that the usually used formula for the Donnan equilibrium is only formally correct.