VOL 80, No. 4 (2007)

The modern methods and systems for monitoring the redox balance of glass as a key parameter for stabilizing the glass-making process, achieving and reproducibility of the specified performance properties of glass and glass products are considered. It is shown that it is necessary to control the protective function of glass from light radiation by the value of trichromatic characteristics - the dominant wavelength, purity and brightness of color. Il. 5, bibliography: 12 titles.

The results of IR spectroscopy of boric and silicic acids, the main components of the charge for the manufacture of microspheres, are presented. It is proved that in the structures of silicic and boric acids, water is in molecular (crystalline hydrate) and in the form of OH-groups, respectively. A formula is given for calculating the absolute degree of difference between the bands in terms of the wavenumber and intensity. It has been shown that half of the spectral bands of both acids can be used only conditionally for the identification of acids, and among them, almost one third of the bands are basic. The bands at 1195 cm ^-1 in the spectrum of boric acid and at 1180 and 1200 cm ^-1 in the spectrum of silicon are indistinguishable in position and intensity and cannot be used for analysis. The wavenumber is a necessary and sufficient feature for identifying acids in the charge, but in the case of conventionally applicable bands, without taking into account their intensity, the analysis of a mixture of acids is impossible. Tab. 2, ill. 3, bibliography: 13 titles.

By introducing a eutectic additive of the CaO - ZnO - Al ₂ O ₃ - SiO ₂ system and tetragonal zirconia into the alumina synthesized by calcining the hydroxide, dispersion-hardened material with an average bending strength of 580 - 40 MPa, promising as a structural one. The sintering temperature of such ceramics is 1550 ° C. The properties of the eutectics of this system have been analyzed, the optimal composition of the liquid phase has been established, which promotes intensive sintering of aluminum oxide. Tab. 3, bibliography: 5 titles.

We investigated samples of lanthanum lithium titanate with the general formula La _2/3-x Li _3x TiO ₃, which have different vacancy content, which varies with the ratio of lanthanum to lithium. The synthesis procedure, neutron diffraction data of the obtained samples, the results of measurements of the lithium-ion conductivity of equilibrium and quenched samples, nuclear magnetic resonance on ⁷ Li nuclei, dynamic characteristics of heat release (heat absorption) and magnetic susceptibility of some samples are presented. Tab. 1, ill. 6, bibliography: 4 titles.

The use of the method for determining the compaction coefficient and the distance between particles for industrial ceramic slips is shown. High values ??of the compaction coefficient result in increased viscosity and rate of structure formation. The application of the method for determining the physical parameters of the slip mass according to the granulometric composition data makes it possible to evaluate the filtration properties of the slip mass during the casting of sanitary ware. Tab. 1, ill. 1, bibliography: 3 titles.

Thermal reinforcing coatings based on ceramic-forming polymers and modifying refractory oxygen-free nanosized particles have been investigated. It has been established that the use of heat-reinforcing coatings provides an increase in the operating temperatures of fibrous heat-insulating materials by 300 - 500 ° C, an increase in thermal and mechanical characteristics by a factor of 2-3. A new glass-ceramic composite multifunctional material with a thermo-reinforcing coating has been created, which can be used in heat-insulating, heat-shielding and sound-absorbing structures in aerospace engineering and power engineering. Il. 6, bibliography: 3 titles.

Glass-crystalline compositions based on leucite glass with an increased content of fluids and additions of hydroxyapatite or a mixture of hydroxyapatite with fluorite, intended for the manufacture of coatings on titanium implants, are considered. It has been established that masses containing no more than 30% hydroxyapatite in leucite glass are most suitable as glass-crystalline coatings for dentures. Masses with a high content of hydroxyapatite Ca ₁₀ (PO ₄) ₆ (OH) ₂ (more than 30%) can be recommended as coatings for intramandibular titanium implants. Tab. 2, ill. 3, bibliography: 8 titles.

The conditions for the synthesis of porous biocomposite materials based on calcium phosphates for the manufacture of implants with the given parameters of the pore structure, the desired level of physicochemical and biological properties for clinical use have been determined. The role of the bimodal pore structure in substrate materials for cell cultures is shown. Tab. 3, ill. 3, bibliography: 4 titles.

A composite material was obtained based on synthetic phosphates reinforced with a glass phase in an amount of 50% by weight. The material has a porosity of 48 - 61%, which depends on the choice of the plasticizer and the sintering mode. Sufficient mechanical strength and biochemical solubility of the studied samples allows us to recommend them for practical use as biomaterials. Tab. 3, ill. 1, bibliography: 9 titles.