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arXiv · cond-mat/9706186

Band Formation during Gaseous Diffusion in Aerogels

M. A. Einarsrud·F. A. Maao·A. Hansen·M. Kirkedelen·J. Samseth
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Abstract

We study experimentally how gaseous HCl and NH_3 diffuse from opposite sides of and react in silica aerogel rods with porosity of 92 % and average pore size of about 50 nm. The reaction leads to solid NH_4Cl, which is deposited in thin sheet-like structures. We present a numerical study of the phenomenon. Due to the difference in boundary conditions between this system and those usually studied, we find the sheet-like structures in the aerogel to differ significantly from older studies. The influence of random nucleation centers and inhomogeneities in the aerogel is studied numerically.

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M. A. Einarsrud, F. A. Maao, A. Hansen, M. Kirkedelen, J. Samseth. 1997-06-18. Band Formation during Gaseous Diffusion in Aerogels. https://doi.org/10.1103/physreve.57.6767

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