Janus colloids propelled by light, e.g., thermophoretic particles, offer promising prospects as artificial microswimmers. However, their swimming behavior and its dependence on fluid properties and fluid-colloid interactions remain poorly understood. Here, we investigate the behavior of a thermophoretic Janus colloid in its own temperature gradient using numerical simulations. The dissipative p...

Colloid transport in subsurface has received considerable attention recently because mobile colloids can facilitate the transport of heavy metals in soils to contaminate groundwater. Many studies on colloid mobility in the subsurface consider soils as well-defined porous media. Though similar in many aspects, soils are different from well-defined porous media. The authors emphasize the impacts ...

A convenient "one step" preparation process of molecularly imprinted overoxidized-polypyrrole (oPPy) colloids by chemical polymerization and their high uptake ability and enantioselectivity are described. Since an oxidizing agent gives a different standard redox potential and rate of polymerization, the property of the resulting oPPy colloid can be controlled by the kind and concentration of th...

A three-dimensional particle tracking model for colloid transport in porous media was developed that predicts colloid retention in porous media in the presence of an energy barrier via two mechanisms: (1) wedging of colloids within grain to grain contacts; (2) retention of colloids (without attachment) in flow stagnation zones. The model integrates forces experienced by colloids during transpor...

[1] Contaminant-scavenging colloids are mobilized in the vadose zone during infiltration events, characterized by transient flow regimes. In the research reported here we develop a mathematical model in order to investigate the influences of flow transients on colloid mobilization in unsaturated media. The model solves coupled equations for unsteady pore water flow, colloid release, advective-d...

The reduced hepatic blood flow calculated from hepatic scintigram with 198Au colloid was elucidated as the primary responsible factor for postoperative hepatic insufficiency. However 198Au colloid is no longer in use because of the high levels of radiation. Although 99mTc-phytate behaves similarly to 198Au on imaging, there were discrepancies between the hepatic blood flow index (KL) value and ...

We determine the solvent mediated contribution to the effective potentials for model colloidal or nanoparticles dispersed in a binary solvent that exhibits fluid-fluid phase separation. The interactions between the solvent particles are taken to be purely repulsive point Yukawa pair potentials. Using a simple density functional theory we calculate the density profiles of both solvent species in...