The influence of direct current electric fields on the possible electrokinetic delivery of nano-iron slurry in clay for the purpose of fast and effective remediation of soil contaminants has been tested. Nano-iron can be introduced to soil hydraulically in slurry form, but in tight clay soil, delivery of a uniform distribution of the slurry may be difficult to achieve for effective remediation....

The nonlinear phenomena that occur in the electric double layer (EDL) that forms at charged surfaces strongly influence electrokinetic effects, including electro-osmosis and electrophoresis. In particular, saturation effects due to either dielectric decrement or ion crowding effects are of paramount importance. Dielectric decrement significantly influences the ionic concentration in the EDL at ...

We present a prototype nanofluidic device, developed for the continuous-flow dielectrophoretic (DEP) fractionation, purification, and quality control of sample suspensions for gene vaccine production. The device consists of a cross injector, two operation regions, and separate outlets where the analytes are collected. In each DEP operation region, an inhomogeneous electric field is generated at...

The authors review and project their group’s work in reaction engineering, electrokinetics, thin-film lubrication/wetting, biosensing, mass spectrometry, etc., that share one common mathematical underpinning: singularities. These can be geometric singularities of actual surfaces or objects, where focused electrical, acoustic, optical and shear-stress fields produce anomalous physical phenomena ...

We use fluorescence microscopy to measure the orientation and shape of microtubules-which serve as a model system for semiflexible rods-that are electrophoretically driven. Surprisingly, a bimodal orientation distribution is observed, with microtubules in either parallel or perpendicular orientations to the electric field. The occupancy of these states varies nonmonotonically with the microtubu...

Electrically controlled dynamics of fluids and particles at microscales is a fascinating area of research with applications ranging from microfluidics and sensing to sorting of biomolecules. The driving mechanisms are electric forces acting on spatially separated charges in an isotropic medium such as water. Here, we demonstrate that anisotropic conductivity of liquid crystals enables new mecha...