The most typical results of studies on the chemical and phase compositions of the tungsten oxide films synthesized by different chemical and physical methods, including the films that have undergone addi tional thermal treatment in vacuum and in the air, are reviewed.

The possibility of synthesizing BaTiO 3 ferroelectric powders of different dispersities by the exchange reactions in molten salts is demonstrated. The proposed method has some advantages, such as the possibility of preparing titanate materials of different dispersities and the simplicity and controllability of the chemical process.

Coatings on graphite with a high heat resistance at a temperature of 1400 ° C in an air atmosphere are prepared on the basis of the ZrB 2 -MoSi 2 -SiO 2 system. It is demonstrated that the sealing vitreous layer is formed through oxidation of the composite components. The kinetic analysis of oxidation processes of the ZrB 2 -MoSi 2 composite shows that the coating formation results from a set of concurrent and consecutive chemical reactions. The stages of forming the gas-impermeable layer are revealed, the schemes for oxidation reactions are proposed, and the kinetic parameters of reactions are determined.

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This paper reports on the results of investigations into the surface morphology of hybrid organicinorganic films prepared by the sol-gel method on single-crystal semiconductor silicon. The spin-on-glass films are coated from sols based on tetraethoxysilane. The chemical composition of the films is modified by introducing inorganic compounds (dopants), namely, boric acid and gadolinium nitrate, into the sols. For the purpose of increasing the film thickness, the sols are modified by small amounts (~1 wt %) of polyols that have linear and branched structures, different molecular weights, and different numbers of active functional groups. A substantial change in the surface morphology of the spin-coated films, i.e., the formation of a specific structure of the films under the action of the above dopants and modifiers, is revealed using optical and atomic-force microscopy.