Transport processes in hydrous oxide films

In this reaction sequence the subscript denotes the layer. If p and a) denote the surface concentrations of A and B centers, respectively, with pj + a j = for all j, then one has that 

If dj denotes the volume concentration of species A in layer j then Eq. (18) takes the form 

The latter expression is simply a finite difference59 form of the diffusion equation with the diffusion coefficient given by D = kTze2. 

The voltammetric response of spatially distributed redox centers in a layer of finite thickness to an applied linear or cyclic 

Application of the Laplace transformation method63 to this bounded diffusion problem results, in the case of reversible charge transfer  

Laviron and Saveant et recently proposed a simple multilayer model to describe charge transport through a redox coating of finite thickness. In this approach the film is assumed to be divided into p sublayers each of thickness e = L/p. The concentration of redox centers A and B in each sublayer is assumed constant, the sum being given by Fx, the concentration of active sites. It is further assumed for simplicity that the layer is homogeneous and that the electroactive centers are distributed evenly inside it. Further simplifying assumptions are that no interaction forces exist between the electroactive centers and that the 

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