Binary mixtures of larger and smaller colloids having charges of equal sign display unusual response to low-frequency electric fields. We show here that the previously reported negative torque acting on rodlike particles when in presence of a sea of smaller particles is accompanied by a field-induced clearing of the suspension. Measurements of transmitted intensity performed on mixtures of large (dilute) and small (semidilute) spherical particles indicate that such a clearing effect is universal and due to an anisotropic E2 -dependent redistribution of the small spheres around the large ones. We interpret this behavior as resulting from O (E2) electro-osmotic flows whose magnitude is greatly enhanced by the presence of the small particles.
Field-induced clearing in sphere-sphere and rod-sphere binary mixtures of charged colloidal particles / L. Fornasari, F. Mantegazza, M. L. Jimenez, M. Buscaglia, T. Bellini. - In: PHYSICAL REVIEW E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS. - ISSN 1539-3755. - 79:6(2009).
|Titolo:||Field-induced clearing in sphere-sphere and rod-sphere binary mixtures of charged colloidal particles|
FORNASARI, LUCIA (Primo)
BUSCAGLIA, MARCO (Penultimo)
BELLINI, TOMMASO GIOVANNI (Ultimo)
|Settore Scientifico Disciplinare:||Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)|
|Data di pubblicazione:||2009|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1103/PhysRevE.79.060401|
|Appare nelle tipologie:||01 - Articolo su periodico|