Zaccone Alessio, Wu Hua, Gentili Daniele, Morbidelli Massimo
Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland.
Phys Rev E Stat Nonlin Soft Matter Phys. 2009 Nov;80(5 Pt 1):051404. doi: 10.1103/PhysRevE.80.051404. Epub 2009 Nov 16.
Using an approximation scheme within the convective diffusion (two-body Smoluchowski) equation framework, we unveil the shear-driven aggregation mechanism at the origin of structure formation in sheared colloidal systems. The theory, verified against numerics and experiments, explains the induction time followed by explosive (irreversible) rise of viscosity observed in charge-stabilized colloidal and protein systems under steady shear. The Arrhenius-type equation with shear derived here, extending Kramers' theory in the presence of shear, clearly demonstrates the important role of shear drive in activated-rate processes as they are encountered in soft condensed matter.
在对流扩散（双体斯莫卢霍夫斯基）方程框架内采用一种近似方案，我们揭示了剪切驱动的聚集机制，它是剪切胶体系统中结构形成的起源。该理论经过数值和实验验证，解释了在稳定剪切下电荷稳定的胶体和蛋白质系统中观察到的诱导时间，随后是粘度的爆发式（不可逆）上升。这里推导的带有剪切的阿仑尼乌斯型方程，在存在剪切的情况下扩展了克莱默斯理论，清楚地表明了剪切驱动在软凝聚态中遇到的活化速率过程中的重要作用。
