Knudsen self- and Fickian diffusion in rough nanoporous media
نویسندگان
چکیده
منابع مشابه
Knudsen Self- and Fickian Diffusion in Rough Nanoporous Media
The effect of pore surface roughness on Knudsen diffusion in nanoporous media is investigated by dynamic Monte-Carlo simulations and analytical calculations. A conceptual difference is found between the roughness dependence of the macroscopic, transport diffusivity and the microscopic, selfdiffusivity, which is reminiscent of diffusion in zeolites, where a similar difference arises due to adsor...
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1. Introduction Gas diffusion in mesoporous media is often in the Knudsen regime, cross sections of the pores being considerably smaller than the intrinsic molecular mean free path. Coppens [1] predicted the effect of fractal wall roughness on Knudsen self-diffusivity K D in a channel. A " trapping " process was identified as the cause of reduction of
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ژورنال
عنوان ژورنال: The Journal of Chemical Physics
سال: 2003
ISSN: 0021-9606,1089-7690
DOI: 10.1063/1.1584652