Partitioning at Low Concentrations

With an increasing the interaction term becomes nonnegligible, which oc-cnrs first for fij, because 4 e. Then, Eq. 4.35 is simplified to 

The right-hand side should be rather expressed by the virial expansion of ju,  

The increase in results in an increase in K because U2 0 in the good solvent. The concentration increases more rapidly in the pore than it does in the surrounding solution. The positive second virial coefficient is the driving force to increase K. 

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