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A Model for the Two-Phase Behavior of Fluids in Dilute Porous Media

Published online by Cambridge University Press:  10 February 2011

James P. Donley ,
Rebecca M. Nyquist  and
Andrea J. Liu
James P. Donley
Affiliation:
Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
Rebecca M. Nyquist
Affiliation:
Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
Andrea J. Liu
Affiliation:
Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
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Abstract

Experiments show that the coexistence region of a vapor-liquid system or binary liquid mixture is dramatically narrowed when the fluid is confined in a dilute porous medium such as a silica aerogel. We propose a simple model of the gel as a periodic array of cylindrical strands, and study the phase behavior of an Ising system confined in this geometry. Our results suggest that the coexistence region should widen out at lower temperatures, and that the narrowness observed near the critical point may be a fluctuation-induced effect.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 407: Symposium M – Disordered Materials and Interfaces-Fractals, structure and Dynamics , 1995 , 15
Copyright
Copyright © Materials Research Society 1996

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References

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