Article révisé par les pairs
Résumé : A theoretical approach is proposed to explain the relaxation against frequency of the electrical properties of an heterogeneous system, previously observed and reported. The dispersion of the dielectric constant and of the conductivity of a Pyrex plug embedded in an electrolyte solution is interpreted, using the Maxwell equations and a triphasic model, where the double layer surrounding the particles is considered as the third phase. The computed curves are in good agreement with the experimental data. Different parameters governing the relaxation process (electrolyte concentration, magnitude of the surface conductance, particle radius, and relative volume fractions) are also considered. © 1976.