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arXiv · 0912.4284

Many-Body Force and Mobility Measurements in Colloidal Systems

Jason W. Merrill·Sunil K. Sainis·Jerzy Blawzdziewicz·Eric R. Dufresne
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Abstract

We demonstrate a technique for simultaneously measuring each component of the force vectors and mobility tensor of a small collection of colloidal particles based on observing a set of particle trajectories. For a few-body system of micron-sized polymer beads in oil separated by several particle radii, we find that the mobility tensor is well-described by a pairwise Stokeslet model. This stands in contrast to the electrostatic interactions, which were found to deviate significantly from a pairwise model. The measurement technique presented here should be simple to extend to systems of heterogeneous, non-spherical particles arranged in arbitrary 3D geometries.

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Jason W. Merrill, Sunil K. Sainis, Jerzy Blawzdziewicz, Eric R. Dufresne. 2009-12-22. Many-Body Force and Mobility Measurements in Colloidal Systems. https://arxiv.org/abs/0912.4284

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