Models for Porous Structures

One important, but often not clearly defined variable in the characterisation of porous layers, is the shape (or geometry) of the pores. In order to interpret the characterisation results and relate pore size to physical models, it is often 

In addition, it is not the average pore size which is the determining factor in membrane performance, but the smallest constriction in the porous medium. Indeed some characterisation techniques determine the dimension of the pore entrance rather than the pore size. Such techniques often provide better information about permeation related characteristics, provided that through pores are concerned. 

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