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Published on: June 9, 2016
Characterization of Concentrated Magnetic Colloids by Measurements of Frequency Dependence of AC Magnetic
1Center for Materials for Information Technology, The University of Alabama, Tuscaloosa, Alabama, 35487-0209
Abstract:
The AC magnetic susceptibility frequency dependence in the range 10 Hz-10 kHz is used to study concentrated magnetic colloids. Different theoretical and empirical models are used to describe the frequency dependence. The magnetic analogue of the Cole-Cole model is found to be most suitable. Values of the model fitting parameters and the relaxation time distribution provide information about the dispersability, viscoelastic properties, and interparticle interactions in the magnetic colloids. Copyright 1998 Academic Press.
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