Original scientific paper

Electroacoustic Characterization of Bidisperse Suspensions

María L. Jiménez ; Department of Applied Physics, Faculty of Science, University of Granada, Spain
Francisco J. Arroyo ; Department of Physics, Faculty of Experimental Science, University of Jaén, Spain
Silvia Ahualli ; Department of Applied Physics, Faculty of Science, University of Granada, Spain
Raúl Rica ; Department of Applied Physics, Faculty of Science, University of Granada, Spain
Ángel V. Delgado ; Department of Applied Physics, Faculty of Science, University of Granada, Spain

Abstract

Electroacoustic techniques are promising tools for the size determination and electrokinetic
characterization of concentrated colloidal suspensions. When particles are not homogeneous in
size and/or density, the dynamic mobility obtained is a kind of average of the mobilities of
every particle. In this paper, we try to discern which averaging procedure provides a better
description of the dynamic mobility of bidisperse suspensions consisting of a mixture of two
very different types of particles. The results show that the amplitude of the sound wave induced
by an applied ac field (electrokinetic sonic amplitude) is not just the sum of the amplitudes
of the waves generated by every particle but has a larger contribution from the larger particles,
although the small size entities considerably influence the behaviour of the latter because of
their interference in the fluxes of the fluid and ions around them.

Keywords

electrokinetics; ESA; polydisperse suspensions; electroacoustics

Hrčak ID:

18669

URI

https://hrcak.srce.hr/18669

Publication date:

30.11.2007.

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