Equation of state approach Neumanns method

Neumann and coworkers proposed that the solid-liquid interfacial tension should be a function of the liquid and ideal solid surface tensions, Jsl = /(7sl fly) They assumed the ideal solid surface to be smooth, homogeneous, rigid and non-deformable. Moreover, there is no dissolution of the solid in the liquid drop, nor is there any adsorption of any of the 

Neumann and co-workers demonstrated that the minimum ySL was zero and could not be negative. Later they modified Equation (696) as follows, to avoid the discontinuity as the denominator goes to zero 

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