[en] The structure of tin-telluride glasses is studied by the use of the IR spectroscopy method. The existence of the [SiO₄], [BO₄], [PbO₄], [TeO₃] and [TeO₄] groupings in the structure of glasses under investigation is established. It is shown that with a growth of the TeO₂ content one observes the increase of the [TeO₄] groups in the glass structure

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[en] One section of the P₂O₅-Nb₂O₅-TiO₂-Fe₂O₃ system containing 20 mole % Nb₂O₅ and a series of glasses with the molecular ratio P₂O₅:TiO₂:Fe₂O₃=2:1:1 and Nb₂O₅ content of 0-35 mole % were studied by ir spectroscopy (KBr press technique). Changes of ir spectra at 400-1400 cm^-1 are discussed. The presence of P-O groupings of chain and ring types are found. With increasing P₂O₅ content, the portion of elements with the chain structure increases

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[en] A complex systematic investigation of the structural state of B³⁺ ions in glasses of zirconium-containing systems has been carried out using electronic microscopy, IR spectroscopy, EPR and Raman scattering. It has been ascertained that the structural state of boron is determined not only by the quantitative content of B₂O₃ and by the ratio B₂O₃/Na₂O+CaO, but also by the structural position of the oxides Al₂O₃ and ZrO₂. Oxides of alkali and alkaline-earth metals provide the polarized oxygen required for building of the tetrahedrons, BO₄. The oxides Al₂O₃ and ZrO₂, on the contrary, compete with boron in using the weakly-bound oxygen, thus increasing the amount of three-coordinated boron

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[en] High-temperature ceramics of improved hardness was obtained on the basis of zirconium boride with 3060 deg C melting point. Studies on development of ceramic materials, based on oxynitride (Si₃N₄ + refractory pxodes) and oxycarbide (SiC + refractory oxides) systems, were performed. They enable to change thermal conductivity, heat resistance and high-temperature strength of ceramics in wide ranges, providing high mechanical strength

[en] Crystallization of glasses having the composition of RO-Al₂O₃-TiO₂-SiO₂ (R=Ba, Sr) yields, as the main phases, barium or strontium metatitanate, or solid solutions based on them. A tangible effect on the nature of the resulting phase is produced by the ratio of BaO:SrO. When BaO and SrO are present together in the glasses, strontium titanates are most likely to form, and only in the case of a substantial predominance of BaO, barium metatitanate or a solid solution on its base is formed. Alumosilicoxygen groups of the [SiAlO₇] type are more stable in the presence of barium

[en] The SrO-BaO-Al₂O₃-TiO₂-SiO₂ system is studied. It is shown that in the samples with higher SrO concentration in comparison with BaO and at their equal quantities solid solutions on the base of triclinic strontium anorthite are formed, and at the increased BaO content - on the base of monoclinic celsian. The homogeneity range of the BaAl₂Si₂O₈ celsianic form is relatively narrower in comparison with SrAl₂Si₂O₈. The Al₂O₃/(SrO + BaO) ratio considerably influence isomorphism in the SrO-BaO-Al₂O₃-Ti0₂-SiO₂ system: in the studied glasses the increase of this value from 0.5 to 1.25 reduces the temperature of the beginning of solid solution formation from 1470 to 1220 K