Hattori Y, Ushiki H, Courbin L, Panizza P
Graduate School of Bio-applications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Koganei 184-8588, Japan.
Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Feb;75(2 Pt 1):021504. doi: 10.1103/PhysRevE.75.021504. Epub 2007 Feb 22.
The present contribution reports on the observation of two diffusive relaxation modes in a concentrated microemulsion made of repulsive droplets. These two modes can be interpreted in the frame of Weissman's and Pusey's theoretical pioneering works. The fast mode is associated to the collective diffusion of droplets whereas the slow one corresponds to the relaxation of droplet concentration fluctuations associated with composition and/or size. We show that (i) repulsive interactions considerably slow down the latter and (ii) a generalized Stokes Einstein relationship between its coefficient of diffusion and the Newtonian viscosity of the solutions, similar to the Walden's rule for electrolytes, holds for concentrated microemulsion systems made of repulsive droplets.
本论文报道了在由相互排斥的液滴构成的浓微乳液中观察到的两种扩散弛豫模式。这两种模式可以在魏斯曼（Weissman）和普西（Pusey）的开创性理论工作框架内得到解释。快模式与液滴的集体扩散相关，而慢模式则对应于与组成和/或尺寸相关的液滴浓度涨落的弛豫。我们表明：（i）排斥相互作用显著减缓了后者；（ii）对于由相互排斥的液滴构成的浓微乳液体系，其扩散系数与溶液的牛顿粘度之间存在类似于电解质的瓦尔登（Walden）规则的广义斯托克斯 - 爱因斯坦关系。
