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Xerogels and powders of solid solutions based on zirconium dioxide are synthesized by the method of the coprecipitation of hydroxides from aqueous solutions of nitrate salts of zirconium, yttrium, aluminum, and cerium with an aqueous solution of ammonia. The characteristics of the resulting materials are studied. The influence of stabilizers and additives on their synthesis, sintering, and properties is assessed. [ABSTRACT FROM AUTHOR]

By using the method of coprecipitation of hydroxides in the ZrO2–CaO–MgO system, xerogels, powders, and ceramics based on them are obtained. The effect of low temperatures during the preparation of precursors on the phase composition and physicochemical properties of the materials is studied. It is shown that the use of precipitate's cryotreatment makes it possible to reduce the open porosity and water absorption of the ceramics. [ABSTRACT FROM AUTHOR]

Xerogels and powders of a solid solution based on zirconium dioxide are synthesized by the method of coprecipitation of hydroxides from aqueous solutions of salts of zirconium nitrate ZrO(NO3)2⋅2H2O, aluminum Al(NO3)3⋅9H2O, and cerium Ce(NO3)3⋅9H2O with an aqueous 1 M solution of ammonia NH4OH. A dense ceramic with low porosity and water absorption is obtained. The effect of the ultrasonic treatment of the precipitate and mechanical treatment of the xerogel on the physicochemical properties of the obtained materials is evaluated. [ABSTRACT FROM AUTHOR]

By using the method of coprecipitation of hydroxides in the ZrO2–CaO–MgO system, xerogels, powders, and ceramics based on them are obtained. The effect of low temperatures during the preparation of precursors on the phase composition and physicochemical properties of the materials is studied. It is shown that the use of precipitate's cryotreatment makes it possible to reduce the open porosity and water absorption of the ceramics. [ABSTRACT FROM AUTHOR]

Samples of a series of homogeneous solid solutions Sr3–xB2Si1–xO8–3x:yEu3+ (x = 0.63, y = 0.001, 0.01, 0.1, 0.2, 0.4) were obtained by crystallization from the melt. Investigations were carried out by X-ray phase analysis and thermal analysis. The unit cell parameters and the melting and crystallization temperatures of solutions were determined. [ABSTRACT FROM AUTHOR]

Samples of a series of homogeneous solid solutions Sr3–xB2Si1–xO8–3x:yEu3+ (x = 0.63, y = 0.001, 0.01, 0.1, 0.2, 0.4) were obtained by crystallization from the melt. Investigations were carried out by X-ray phase analysis and thermal analysis. The unit cell parameters and the melting and crystallization temperatures of solutions were determined. [ABSTRACT FROM AUTHOR]

Samples of 8 compositions in the cross section Sr3B2O6–Sr3B2SiO8 of the SrO–B2O3–SiO2 system were obtained by solid-phase synthesis and crystallization of melts. Phase formation processes were studied by X-ray phase analysis in the temperature range 1000–1350°C. The temperature of the beginning of the formation of solid solutions based on Sr3B2SiO8 in the considered section is determined. The existence of an unknown phase in the concentration range Sr3B2O6–SrSiO4–Sr2B2O5 was found. [ABSTRACT FROM AUTHOR]

The kinetics of polycondensation in solutions during the liquid-phase synthesis of ceramic material precursors based on a SrO-B2O3-SiO2 system are studied by spectrophotometry. The ratio between the quantitative content of tetraethoxysilane and the reaction rate of the formation of polymer forms is proved. [ABSTRACT FROM AUTHOR]