Reversal permanent charge and reversal potential: case studies via classical Poisson-Nernst-Planck models
نویسندگان
چکیده
In this work, we are interested in effects of a simple profile of permanent charges on ionic flows. We determine when a permanent charge produces current reversal. We adopt the classical Poisson-NernstPlanck models of ionic flows for this study. The starting point of our analysis is the recently developed geometric singular perturbation approach for Poisson-Nernst-Planck models. Under the setting in the paper for case studies, we are able to identify a single governing equation for the existence and the value of the permanent charge for a current reversal. A number of interesting features are established. The related topic on reversal potential can be viewed as a dual problem and is briefly examined in this work too.
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