Dynamic surface tension reduction values

From the discussion of dynamic surface tension (Chapter 5, Section IV), the maximum rate of reduction of surface tension occurs when t = t, the time required for the surface tension to reach half of the value between that of the solvent, y , and the meso-equilibrium surface tension value, ym. From equation 5.3, it has been shown (Rosen, 1991) that... 

The combined evidence of all three class types of surfactant suggest a strong degree of common behaviour in their dynamics in aqueous gelatin solution they all exhibit a maximum efficiency in DST reduction as their homologous series are ascended. Efficiency can be defined in several ways. Here, efficiency is represented in two different ways, both of which are designed to be independent of absolute values of surface tension lowering. The results for the three classes can then be combined and compared. 

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