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Electrokinetic transport of heterogeneous particles in suspensionThe Smoluchowski equation for electrophoresis predicts that the electrophoretic velocity of a particle is proportional to its zeta potential but not its size, shape, or orientation. Furthermore, the equation predicts that the rotation rate is identically zero. The Smoluchowski equation fails for heterogeneous particles (i.e., those with nonuniform zeta potentials). Recent theories and experiments show that particles with a dipole moment of zeta potential rotate into alignment with an externally applied electric field. For doublets (particles composed of two spheres) the rotation rate depends on (1) whether the spheres are rigidly rocked or freely rotating, and (2) the gap distance between the spheres. The relative configuration of two coagulated spheres is determined by the colloidal forces of the system. The goal of our research is to use measurements of electrophoretic rotation to determine the gap between two spheres of a colloidal doublet and also to determine whether or not the doublet is rigid.
Document ID
19950008167
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Velegol, D.
(Carnegie-Mellon Univ. Pittsburgh, PA, United States)
Garoff, Stephen
(Carnegie-Mellon Univ. Pittsburgh, PA, United States)
Anderson, John L.
(Carnegie-Mellon Univ. Pittsburgh, PA, United States)
Date Acquired
September 6, 2013
Publication Date
August 1, 1994
Publication Information
Publication: NASA. Lewis Research Center, Second Microgravity Fluid Physics Conference
Subject Category
Inorganic And Physical Chemistry
Accession Number
95N14581
Funding Number(s)
CONTRACT_GRANT: NAG8-964
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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