Diffusion in a Binary Critical Mixture

At a critical mixing point for a two-component liquid composed of species a and p, the order parameter is the concentration. For an incompressible fluid. 

This relation does not depend on Eq. (85), although the two equations agree in this case. Equation (126) immediately yields 

Away from the critical point, typically D/r) 10 [A A),.o(s = 0)] D decreases and 17 increases as the critical point is approached. Thus, Dk(s) may always be neglected with respect to 17 (5) on the right-hand side of Eq. (130). In the absence of mode-mode effects, 17 (s) would be independent of k and s for small fc, s, even near a critical point. Furthermore, the actual critical anomaly of 77 is weak. Thus, we expect that the substitution 17 (j) 170(0) = 17 in Eq. 

Equations (136) illustrate many of the salient points of mode-mode coupling. We are considering large with kc. shows a major 

Of course, one must always be careful not to read too much into explanations like that just given nevertheless, we do feel that a considerable amount of truth is contained in the droplet picture. We hasten to point out that the 6 in Eq. (136a), which occurs in the usual Stokes-Einstein law with stick boundary conditions, only occur because we have used O-Z theory this has been stressed by Swinney et In addition, note that droplet diffusion is a 

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