We present direct depletion potential measurements for a single colloidal sphere close to a wall in suspensions of charged colloidal rods. In contrast to earlier studies of purely entropic systems (Helden et al. Phys. Rev. Lett. 2003, 90, 048301), here electrostatic interactions are important. These enhance the depletion attraction and lead to repulsive parts in the interaction potentials, indi...

A mean-field theory for the dynamics of equilibrium suspensions of colloidal hard spheres near the glass transition is presented based on the standpoint recently proposed by the present author. It is shown that although the relative magnitude of the density fluctuations to the mean equilibrium density is small even near the glass transition, they are described by a nonlinear stochastic equation...

Computer simulations of colloidal suspensions are prohibited by slow equilibration as very different length and time scales are involved for the various species. This is the reason that most simulations involve some degree of coarse-graining, whereby the degrees of freedom of the microscopic particles are traced out, and the mesoscopic particles interact with an effective potential, resulting i...

It is often assumed that the viscoelastic properties of dense colloids are determined by the colloid volume fraction, the interaction potential, as well as the particle size distribution and shape. The dependence of the viscoelastic behavior of particle suspensions and gels on these parameters has been widely studied, and is well understood in many cases. In contrast, our knowledge on the influ...

We consider tracer diffusion in colloidal suspensions under solid loading conditions, where hydrodynamic interactions play an important role. To this end, we carry out computer simulations based on the hybrid stochastic rotation dynamics-molecular dynamics (SRD-MD) technique. Many details of the simulation method are discussed in detail. In particular, our choices for the SRD-MD parameters and ...

The rheology of suspensions of Brownian, or colloidal, particles (diameter d≲1  μm) differs markedly from that of larger grains (d≳50  μm). Each of these two regimes has been separately studied, but the flow of suspensions with intermediate particle sizes (1  μm≲d≲50  μm), which occur ubiquitously in applications, remains poorly understood. By measuring the rheology of suspensions of hard spher...

SiO2-ZrO2 sols have been prepared via acid catalysis using a commercial colloidal suspension of zirconia and two silica alkoxides; tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES). Suspensions with 10, 15 and 25-mol% of ZrO2 were prepared. The stability of the suspensions was followed by rheological measurements showing that the amount of water incorporated with the colloidal suspensio...

I discuss the importance of spatial and temporal variations in particle volume fraction to understanding the force response of concentrated colloidal suspensions and granular materials.

Jamming phenomena arise in many systems. Granular materials, glasses and colloidal systems are just a few examples of it. This paper summerizes current effort of unifying these phenomena into a single jamming phase transition. Two examples, granular materials and colloidal suspensions, are discussed in detail to illusrate the idea. The strengths and weaknesses of this picture are addressed at t...