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The paper presents the results from studies of the electrical and magnetic properties of an inhomogeneous percolated medium based on the theory of percolation. The application of this theory has a wide and varied range. Examples include hopping conductivity in semiconductors, properties of porous materials, etc. It was found that, with approaching the percolation threshold pc = 0.35, the resistivity decreases, and the electrical conductivity increases accordingly. An increasing number of individual ferromagnetic nanogranules in (p)–Fe2O3–(1–p) (MBT) composites merge with the formation of individual Fe2O3 clusters in the bentonite matrix, which combine to form a continuous network of clusters. This is due to the fact that the resistivity ρ of the composite is mainly determined by the magnetic component of the latter. [ABSTRACT FROM AUTHOR]

The paper presents the study results on the influence of the alternating current's frequency on the value of active resistance. It has been revealed that the value of the active resistance increases to a minimum value with an increase in the frequency of the alternating field, and it increases sharply with a further increase in the frequency. It is shown that the cause of the growth of active resistance is the skin effect. [ABSTRACT FROM AUTHOR]

The temperature dispersion of dielectric properties of polyethylene-based composites and nanoclays of the Na+-montmorillonite type is studied. It was found that as a result of the heating–cooling cycle, the dielectric characteristics of samples take on new values, which are preserved for some time. It is assumed that this effect is due to thermally stimulated processes of redistribution of charges at the filler–matrix boundary and their accumulation in deeper traps and, as a consequence, emergence of nonequilibrium states of the medium. [ABSTRACT FROM AUTHOR]

The current−voltage characteristics and the resistivity of composite resistors (varistors) based on a nonpolar polyethylene and bentonite (a clay mineral) were investigated. It was found that the content of composite components influences to the current−voltage characteristics and the magnitude of resistivity. It was shown that when increasing the molar content of the filler, the magnitude of resistivity decreases exponentially. [ABSTRACT FROM AUTHOR]