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Polymer composite materials based on CuS/ CdS, Cu 2 S/CdS and Ag 2 S/CdS were obtained by substitution of Cd with Ag, Cu (II) and Cu (I) ions in the CdS rodlike nanocrystalline and investigated their electrophysical properties. It was found that the electrical conductivity of CuS/CdS heterostructure is in five orders higher compared to the CdS. It was shown that the values of the complex permittivity at identical content of CuS and Cu 2 S nanoparticles are more than 40 % higher for the 0.3 Cu 2 S/CdS-PVDF system in comparison with the 0.3 CuS/CdS-PVDF.

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Nanosize nickel ferrite was synthesized by the sol-gel autocombustion method. The surface of nickel ferrite was modified by copper sulphide with the volume fractions from 0.2 to 0.42. For the CuS/NiFe2O4 composites the values of complex permittivity and permeability in the microwave range, values of conductivity at low frequencies and magnetic characteristics were investigated. Polymer composites CuS/NiFe2O4-polychlorotrifluoroethylene (PCTFE) were obtained by hot pressing technique. With an increase in the content of copper sulphide of polymer composites, an increase in the values of the complex dielectric constant in the microwave range of 2-3 times was observed. The values of electrical conductivity for the 0.2CuS/NiFe2O4-PCTFE system are 4-5 orders of magnitude lower than for the 0.42CuS/NiFe2O4-PCTFE system with an increase in the concentration of copper sulphide in polymer composites. The change in the ratio of the conducting and magnetic components in the studied system makes it possible composites with adjustable permittivity and permeability in the microwave range.

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The nanocomposites barium ferrite/carbon nanotubes modified with copper iodide are synthesized by the sol-gel autocombustion method. Electrophysical properties in the microwave range and at low frequencies at room temperature of barium ferrite composites/carbon nanotubes/CuI-polychlorotrifluoroethylene (PCTFE) are studied. As shown, the insertion of composites into PCTFE leads to an increase of the values of complex dielectric permittivity of 5-7 times and electrical conductivity by 2 orders of magnitude in comparison with a system that contains unmodified components.

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Вариационным методом, в рамках модифицированного метода эффективной массы, получен энергетический спектр основного состояния экситона, движущегося в объеме квантовой точки, помещенной в воздух, как функция радиуса квантовой точки. Установлено, что в запрещенной зоне квантовой точки селенида цинка возникает зона экситонных состояний, расположенная у дна зоны проводимости. Показано, что уменьшение ширины запрещенной зоны в такой наносиcтеме обусловлено переходом электрона с квантоворазмерного уровня, расположенного в валентной зоне квантовой точки, на уровни зоны экситонных состояний.