Static electricity charged species concentration

Here er is the relative -> permittivity (static dielectric constant) of the solution, 0 is the permittivity of free space, e is the unit charge on the electron (- elementary electric charge), 3 is the valence of the ionic species i, Ci is the bulk concentration of the adsorbing species i, k is the Boltzmann constant, T is the absolute temperature, and (V(a)) is the time-averaged value of the electric potential difference across the diffuse layer. The diffuse layer capacitance is (very roughly) of the order of 10 pF cm-2. The thickness of the diffuse layer is essentially the - Debye length Ld,... 

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