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First-passage approach for permeable traps.

Mark W Vaughn
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Abstract

Many reactive processes in complex materials involve absorption of diffusing molecules. Recently, there has been interest in particle interaction with partially absorbing (or permeable) traps. Here, we present a simple and efficient method for accounting for the non-diffusion-limited reaction of particles when the flux of particles to the trap is governed by surface permeability. The trapping probability is determined from a one-dimensional Green's function, which results in a simple algebraic expression. This expression, which applies in the region immediately adjacent to the trap, is then used with a first-passage approach far from the trap. When applied to a suspension of permeable traps, the method is seen to give accurate results over the concentration range. The method is applied to the competition of reactive particles in a suspension of permeable spheres with a reactive continuous phase.

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AlgorithmsComputer SimulationDiffusionModels, TheoreticalPorosityJournal ArticleResearch Support, Non-U.S. Gov't

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Mark W Vaughn. 2005-10-01. First-passage approach for permeable traps.. https://doi.org/10.1063/1.2049282

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