Transport Phenomena in Liquids and Solids

The laws of transport phenomena in states other than gases differ among themselves in many respects. This distinction is defined mainly by the difference in their atomic stmc-ture. This will be explained using the example of a monoatomic crystal with a cnbic structure (refer to Table 9.1). 

Count the number of atoms AN enclosed in the spherical layer 4nr Ar. Write this number as  

Here q is the average over the whole crystal volume atomic concentration, and G(r) is the radial distribution function. Wherefrom  

It can be seen from the last expression that when the atomic concentration in the allocated spherical layer is equal to average concentration n, G r) = 1. The function of radial distribution is distinct from unity only in the case when the concentration of atoms in the allocated layer is different from Hq. Hence G(r) characterizes the concentration deviation in a specified layer from the average value. 

If the temperature decreases, the time of settled life is increased near the crystallization point this time increases more and the properties of the liquid come nearer to the properties of solids. On the contrary, if the temperature rises, coming nearer to the boiling point, the time of settled life decreases and the liquid s properties become similar to those of gas. 

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