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On the possibility of spontaneous chemomechanical oscillations in adsorptive porous media.

ABSTRACT: We derive general conditions for the emergence of sustained chemomechanical oscillations from a non-oscillatory adsorption/desorption reaction in a gas/solid porous medium. The oscillations arise from the nonlinear response of the solid matrix to the loading of the adsorbed species. More particularly, we prove that, in order for oscillations to occur, adsorption of the gas must in general cause a swelling of the solid matrix. We also investigate the prototypical case of Langmuir kinetics both numerically and analytically.This article is part of the theme issue 'Dissipative structures in matter out of equilibrium: from chemistry, photonics and biology (part 2)'.

SUBMITTER: Bullara D

PROVIDER: S-EPMC6232597 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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On the possibility of spontaneous chemomechanical oscillations in adsorptive porous media.

Bullara D D De Decker Y Y Epstein I R IR

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences 20181112 2135

We derive general conditions for the emergence of sustained chemomechanical oscillations from a non-oscillatory adsorption/desorption reaction in a gas/solid porous medium. The oscillations arise from the nonlinear response of the solid matrix to the loading of the adsorbed species. More particularly, we prove that, in order for oscillations to occur, adsorption of the gas must in general cause a swelling of the solid matrix. We also investigate the prototypical case of Langmuir kinetics both nu ...[more]

PMID: 30420542

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