Example coupled diffusion and drift in a membrane

To treat the coupled diffusion and drift of a charged ion in a homogeneous membrane, we include both molecular diffusion and electrokinetic drift in the governing 

For a thin membrane in the steady state, and assuming a uniform electric field directed across the membrane,3 we have  

Equation (3.63) is known as the the Goldman-Hodgkin-Katz equation for passive flux of an ion through a membrane [108, 123], 

1 Verify that the relationship k+/k = Keq follows from Equations (3.14) and (3.12). 

4 Although Equation (3.24) is non-linear, a convenient closed form solution is available. Find the solution and make a plot of [A], [E], and [C], given an assumed set of parameters and initial conditions. 

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