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The possibility of using rocks form the Khatsavitskoe, Solokhaul'skoe, and Tugupskoe deposits in Krasnodar Krai in the production of basaltic fibers has been investigated. Using laboratory single-spinneret setup it is shown that continuous, thickened, and rough fibers are formed from melts of these rocks in a wide temperature interval. Using a setup with an induction method of melting the raw materials and acoustic blowing of the melt with compressed air, commercial prototype batches of superthin staple fibers, whose main technical characteristics fall into the range regulated by GOST 4640-93, were obtained. [ABSTRACT FROM AUTHOR]

Dielectric IR spectroscopy and Raman scattering (RS) spectroscopy have been used to confirm the presence in the structure of lanthanum-borogermanate (LBG) glass of triply coordinated boron atoms which are absent in a LaBGe5 crystal. The grouping ratio [BO3]/[BO4] is independent of the conditions under which the glass is obtained. It is proposed that amorphous nanosize regions of two types with approximately the same chemical composition but different structure are present in the glass. Regions of the first kind contain predominately quadruply coordinated boron atoms and are the basis for the formation of nuclei of stillwellite crystals, while regions of the second kind are more disordered, and a large fraction of the boron atoms in them lie at centers of oxygen triangles. [ABSTRACT FROM AUTHOR]

Investigations of relaxation phenomena in glasses are reviewed. The role of such phenomena in the formation and heat-treatment as well as in other technological processes is shown. The characteristics of the surface layer are indicated from the standpoint of the physics of mesomechanics and the general structural features of inorganic glasses. A number of operational reliability factors for glass articles are examined. [ABSTRACT FROM AUTHOR]

The conditions for obtaining high-transparency glasses are examined. Data on the effect of coloring impurities and additives on the optical and spectral properties of glasses are presented. The role of rare-earth elements and the prospects for using new materials and technologies in the production of articles from high-transparency glasses are shown. [ABSTRACT FROM AUTHOR]

The effect of the composition of mix based on different silica raw material and the oxidation-reduction characteristic of the components on the foaming process in obtaining foam-glass-crystalline materials is examined. It is established that foam-forming mixes belonging to the transitional oxidation-reduction group, whose oxidation coefficient lies in the range 25 – 100 are optimal for foaming. The oxidative and reducing mixes are characterized by a low foaming ratio and high degree of nonuniformity, which requires adjusting the composition by changing the ratio of the reducer oxidizer. [ABSTRACT FROM AUTHOR]

The fining of glass is closely related with the oxidation-reduction potential of the glass, which is determined by means of an indication index—the fraction of bivalent iron, which is proportional to the absorption of the glass in the range 900 – 1100 nm. The appearance of seeds in optical glasses is explained by elevated solubility of nitrogen in the molten glass with an elevated reduction potential. Admixing cullet which possesses a reducing potential and vice versa destroys the solubility of sulfur in the molten glass and increases the risk of the appearance of seeds and foaming of the molten glass. [ABSTRACT FROM AUTHOR]

Methods for recycling mixed cullet, which is a constituent of solid common wastes, are analyzed. It is shown that the problem of recycling wastes of this form remains topical. It is established experimentally that the method of mechanochemical activation makes it possible to obtain a mixed alkaline binding substance which is promising for the production of unfired heat-insulating materials with high mechanical properties. [ABSTRACT FROM AUTHOR]

Heat losses are studied for a tunnel furnace used for firing porcelain and refractory materials. Calculations of the heat losses through the arch of the furnace are performed using diatomaceous crumb and granulated foam glass ceramic as heat-insulating fill. Cost-effectiveness calculations show that there is an advantage to using granulated foam glass ceramic. [ABSTRACT FROM AUTHOR]

The results of experimental studies of the production of low-melting glasses with low lead oxide content for fluxes of silicate paints based on two borate systems not previously studied are presented. The predictable changes of the softening onset temperature, the total flow, and the CLTE are established. The crystallization power of the glasses is studied. The results of these investigations are used as a basis to propose compositions with 20–25 wt.% PbO (molar content 6–10%) and burn-in temperature of paints based on them 560–580°C. [ABSTRACT FROM AUTHOR]

Special heat-shielding materials cover the outer surfaces of space shuttles. These materials must also be protected from erosion, moisture, and so forth by thermal control coatings. A series of works was conducted at VIAM on the development and improvement of erosion-resistant thermal control coatings and their manufacture and usage technologies. [ABSTRACT FROM AUTHOR]

The composition of the elements of a fluorescent lamp is described. The functions and requirements of the bulb, fluorescent coating, electrodes, and other parts of the lamp are presented. Improved technologies for manufacturing the elements of a compact fluorescent lamp that can significantly increase the quality and lifetime of manufactured lamps and significantly expand their practical applications are proposed. [ABSTRACT FROM AUTHOR]

The procedure for calculating and designing melting tanks for glassmaking furnaces used in the manufacture of container glass is examined. It is shown that mathematical modeling of the internal heat and mass transfer makes it possible to increase substantially the quality of the design solutions, whose implementation creates objective prerequisites for attaining a high energy efficiency and productivity for glassmaking furnaces. [ABSTRACT FROM AUTHOR]

The possibility of partial or complete replacement of PbO in fusible glass solders by less toxic components is investigated. It is found that it is impossible to find a full-fledged replacement for glasses in the lead-borate eutectic, used as the glass base in glass soldering compositions for sealing glass ceramic packages of integrated microcircuits at temperatures 390 – 420°C, within the systems PbO – P2O5– ZnO – B2O3,V2O5– P2O5– ZnO – B2O3, and TeO2– PbO – V2O5– Bi2O3 with different additives and total mass content of class-I hazard components not exceeding 70%. [ABSTRACT FROM AUTHOR]

The solubility of copper-containing calcium–phosphate glasses is determined as a function of the ratio CaO:P2O5, Al2O3 additions, and CuO content. The glasses are characterized by high solubility in boiling water. The recorded flow of copper ions into the water ranges from 60 to 125 ppm; this makes it possible to classify the synthesized glasses as biocides. The ratio of the modifying cations and glass former, determining the structure of the phosphorus–oxygen framework of the glass, has the greatest effect on the solubility of the glass; the introduction of Al2O3 and substitution of copper oxide for calcium oxide has the weakest effect. [ABSTRACT FROM AUTHOR]

The main factors associated with the service of refractories mainly in the melting tanks of glassmaking furnaces are examined. The main technological factors, a description, and the scheme of the technological cycle for the production of refractories at the Domodedovo Plant for Manufacturing Electro-Smelted Articles are presented. [ABSTRACT FROM AUTHOR]

Analytical expressions are obtained for the bulk density of monodispersed powder systems, taking account of the properties of the particles. The structural and percolation approaches as well as taking account of the boundary layer thickness substantially simplify the evaluation of the properties of powder filled compositions. It is shown that the computed data are good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

A method is proposed for calculating the composition dependences of various properties of three-component alkali-silicate glasses in the systems Na2O – K2O – SiO2 and Li2O – K2O – SiO2, one component of which is the homogenizing alkali oxide K2O. The dependences of the corresponding properties on the alkali oxide content in the two-component alkali-silicates systems Li2O – SiO2, Na2O – SiO2, and K2O – SiO2 were used as parameters in the computational relation. Comparing the computed data and experimental measurements for the density and refraction supports the assumptions forming the basis of the proposed model. [ABSTRACT FROM AUTHOR]

A method is proposed and used to calculate the viscosity of glass and glass crystal compositions in the foaming temperature range. It is determined that for the glass phase content lower than 75% the viscosity of a glass crystal composition depends on the ratio of the crystal and glassy phases and for glass phase content higher than 75% the viscosity of the composition and foaming ratio are determined mainly by the composition of the glass phase. [ABSTRACT FROM AUTHOR]

The effect of silicon compounds on the formation and growth of natural bone tissue is examined, and the concentrations of silicon compounds in different organ tissues are presented. The inductive action of different implantation substrates containing silica on the vital activity of cultures of osteogenic cells is described. It is suggested that the process resulting in bonding between bone tissue and silicate implantation material is affected by the presence of a substantial number of silanol groups on the surface of the material, which determine its high hydrophilicity. It is shown that the solubility of silicate glasses depends on the presence in them of a phase which corresponds to the composition of liquid glass, and its role in the biodegradation of the materials in physiological media is described. [ABSTRACT FROM AUTHOR]

The compositions suitable for obtaining foam-glass-crystalline materials from aluminosilicate initial materials (for the example of zeolite and greenstone) by means of a dual-stage technology at temperatures not exceeding 900°C are examined. The assessment criteria for the initial materials and compositions of the glass granulate are determined. It is shown that under the established conditions aluminosilicate initial material makes it possible to obtain foam-glass-crystalline material with density 250–350 kg/m3 and compression strength up to 2 MPa. [ABSTRACT FROM AUTHOR]

Two specimens of lake diatomites of Karelia differing by the rock-forming types of diatoms and the form, size, and degree of preservation of the valves are investigated. It is determined that the size of the valves has a large effect on the granulometric composition and physical-chemical properties of diatomites. The SiO2 content in the initial samples of diatomites is 70%. After heat-treatment and leaching it increases to 91% and the iron content decreases sharply to 0.075%. After impurities have been removed, lake diatomites are of interest for the production of sheet glass, crystal articles, glazes and enamels, silicate glasses, as well as ceramic articles. [ABSTRACT FROM AUTHOR]

The formation of the microstructure of ceramic based on the calcium hydroxyapatite (HAP) powders containing different byproducts of the synthesis reaction is examined: NaCl, KCl, KCH3COO (K2CO3), NaCH3COO (Na2CO3), NH4NO3, NH4Cl, and NH4CH3COO, which can be conventionally divided into two groups—substances that can be removed during heat-treatment before sintering starts and substances that cannot be removed, forming melts and promoting the formation of new phases. During heat-treatment sodium salts interact with HAP, forming binary sodium-calcium phosphates NaCaPO4 and Ca10Na(PO4)7, and alkali-metal (Na, K) acetates, forming binary carbonates. [ABSTRACT FROM AUTHOR]

A bioinert ceramic based on partially stabilized tetragonal zirconium dioxide has been developed and its chemical and phase composition, microstructure, and physical–technical properties have been investigated. Ceramic heads for endoprostheses for the coxofemoral joint — 28 mm in diameter with less than 0.02 μm roughness R a of the spherical surface and 1 μm deviation from sphericity—have been fabricated. It is shown that the bioceramic which has been developed and the ceramic heads for endoprostheses fabricated from it meet the technical characteristics and parameters required by international standards and their quality is at least as good as that of the analogous articles manufactured by well-known firms. [ABSTRACT FROM AUTHOR]

The effect of using ultradisperse (nano) materials on the strength of glass samples with different chemical composition obtained by high-temperature sintering from powder-forming components is studied. The character of the dependence of the strength on the content (by weight) and type of nanomaterials and the chemical composition of the glass is determined. [ABSTRACT FROM AUTHOR]

The published and patent data on the compositions of glass for optical glass fibres, production technology, and the basic requirements imposed on this glass were analyzed. Synthesis of glass for the light-conducting core in the BaO-B2O3-La2O3-SiO2 system was proposed using modern methods of production of optical glass fibers. [ABSTRACT FROM AUTHOR]

The process for obtaining coloring of the “copper ruby” type in thermochemical treatment of thermally polished glass with copper-containing reagents was examined. Data are reported on the effect of the compositions of the working solutions and process regimes on the character of the coloring and the spectral characteristics of the glasses. Formation of the diffusion layer and the effect of different factors on the quality of the “copper ruby” obtained were investigated, and practical recommendations were given on selecting the optimum coloring regimes. [ABSTRACT FROM AUTHOR]

All of the drawbacks of the ordinary traditionally prepared cullet-containing batch are the cause of constant improvement of batch preparation technologies. It was shown that briquetting of the batch is a function of the cullet content and especially the cullet particle size. [ABSTRACT FROM AUTHOR]

The basic methods of manufacturing porous glass and glass-ceramic materials were examined and analyzed on the example of bioactive materials for bone endoprosthesis. The possibility of using sol-gel technology for forming porous structures with the 3D model developed was demonstrated. [ABSTRACT FROM AUTHOR]

An energy-conserving, ecologically clean technology for producing water glass has been developed. This technology is based on the use of readily available raw materials. A glassmaking furnace is not used. [ABSTRACT FROM AUTHOR]

A morphological approach to supporting decisions made to adjust the operating regime of process equipment on the basis of an analysis of statistical data is described. The method is considered as an example for adjusting the mollification temperature in laminated glass production. [ABSTRACT FROM AUTHOR]

The process of improving the main technical characteristics of a glassmaking furnace is examined: production capacity, specific throughput of the glass mass, and specific consumption of heat for glassmaking. It is shown that these characteristics are intercoupled and interdependent. The heat balance method is used to investigate the dependence of the specific consumption of heat on a number of parameters of the thermal operation of a furnace. It is recommended that the heat balance method be used at the initial stage of designing glassmaking furnaces. [ABSTRACT FROM AUTHOR]

The particulars of the crystallization of calcium-phosphate glass powders with particle size 90–400 µm are investigated, the structure and phase composition of the crystallized materials are determined, and the sintering regime for narrow powder fractions for obtaining the maximum possible open porosity is optimized. The porosity of the sintered glassceramic materials is 25%, and the pore size is of the order of 100 µm. The materials obtained release into a water medium calcium cations and phosphate anions, which is the price for their successful adaptation in a living organism. [ABSTRACT FROM AUTHOR]

The existing hypotheses on the structure of alkali borate glass were comprehensively analyzed. Their imperfection in explaining the dependences of the properties of the glasses on their composition was noted. Alternative schemes of structural borate complexes which more convincingly explain the characteristics of the change in the properties of this glass are proposed. [ABSTRACT FROM AUTHOR]

It is shown that the translucence of a substrate strongly influences light transmission by glass articles modified by sol-gel coatings. In contrast to glass, where light scattering is proportional to the refractive index, an inverse proportionality has been found in the films studied, which can be explained by the influence of porosity on the decrease of the refractive index of the coating. [ABSTRACT FROM AUTHOR]

The possibilities of obtaining pigments with the structure “inorganic nucleus in a ferromagnetic shell” by depositing nickel and copper ferrites on the surfaces of optical-glass microgranules are studied. The porous characteristics, the physical-chemical properties, and the surface structure of the synthesized pigments are investigated. [ABSTRACT FROM AUTHOR]

The influence of various additives on the porization of liquid-glass compositions using new approaches for analyzing experimental data, making it possible to obtain a quantitative assessment of the influence of inorganic additives and salts, is determined. Application of the law of constancy of the volume phase composition of dispersed systems makes it possible to express mathematically the influence of technological parameters (temperature, time) and the form of the types of additives introduced on the porization processes in such compositions. [ABSTRACT FROM AUTHOR]

It is shown that introducing small amounts of P2O5, which do not give rise to opacification and opalescence, into silicate glasses strongly affects the dilatometric properties of glasses. This gives an idea of the structural changes and could be of practical value. [ABSTRACT FROM AUTHOR]

A new paste is proposed for frosting glass surfaces. The action of the paste is based on the physical-chemical process of surface chemical ion exchange. The paste does not contain hydrofluoric acid or its derivatives. The frosting process occurs at 300°C and differs substantially from the existing frosting processes — chemical etching and sandblasting. The morphology of the surface layer of the frosted glass is characterized by a system of microblocks (linear dimensions 50–150 µm) and microcracks (width 100–200 nm). The microblocks have even faces and a smooth frontal surface. The surface morphology of the glass is the same after frosting and subsequent deposition of a metal by chemical reduction. [ABSTRACT FROM AUTHOR]

The general state of the glass industry in Russia at the present stage is analyzed. It is shown that on the basis of the production volume of sheet glass and glass containerware the glass industry is one of the largest industrial sectors in Russia. An intermediate-term forecast of the demand for the main resources—gas, electricity, sand, dolomite, soda, and cullet—is constructed on the basis of a determination of the trends in the further growth of glass production in Russia. [ABSTRACT FROM AUTHOR]

The role of transport phenomena and technological processes in glass production is noted. The salient features of a change in transport phenomena accompanying changes of the temperature and chemical composition of glasses for fused and solidified states of glass are examined. The interrelationship of transport phenomenon is also examined. Glass forming melts possess a high viscosity. The latter has a large effect on transport phenomena associated with particle motion; this effect is also expressed by definite relations. The results of experimental and theoretical investigations, presented in the scientific and technical literature, are discussed from structural and technological standpoints. [ABSTRACT FROM AUTHOR]

It is pointed out that the quantitative determination of glass color is an important current issue and variants of color measurement are examined. [ABSTRACT FROM AUTHOR]

Facing and decorative glass crystal materials were developed from mineral feedstock and technogenic wastes. The effect of the components present in the mineral feedstock in liquation and crystallization of the glasses was investigated. The materials obtained can be used in construction for facing walls. [ABSTRACT FROM AUTHOR]

Experimentally substantiated recommendations on selecting compositions and technologies for synthesis of glass solders with assigned properties within the soldering temperature limits of 390–450°C and CLTE of (60–70) × 10−7 K−1, designed for hermetically sealing the ceramic packages of integrated microcircuits are reported. [ABSTRACT FROM AUTHOR]

Different chemical compositions of glasses and the individual characteristics of their reaction with zirconium-containing refractories are examined. When such refractories are used for lining glass-melting furnaces, it is necessary to consider the chemical compositions of the glass which will be melted in these furnaces. [ABSTRACT FROM AUTHOR]

Studies have shown that when smaller NiS inclusions are present the “heat-soak” method of rejecting toughened glasses does not completely guarantee that these glasses cannot fail spontaneously while in use. It is posited that the reason why glasses fail spontaneously is not so much the polymorphism of NiS as high stresses around NiS inclusions and, in consequence, a limitation on the “life” time of glass in accordance with the kinetic theory of long-term strength. [ABSTRACT FROM AUTHOR]

The data on the ionic staining of glasses are analyzed from the standpoint of ligand field theory. New information is added to the existing information on the staining of glasses by transition-metal compounds. Data on the structure of glass-forming melts and the conditions for the formation of staining complexes are presented. A possible mechanism for amber staining in glasses is discussed. [ABSTRACT FROM AUTHOR]

The use of mid-IR range lasers (3–7 µm) for controlled laser thermal separation of oxide classes is analyzed. It is shown that CO lasers (5.1–6.2 µm) greatly improve the quality of this technology. [ABSTRACT FROM AUTHOR]

It is shown that OH groups affect the technological and physical-chemical properties of glass. The importance of and need for research in this direction are substantiated by the facts that new artificial and natural raw materials are now being used and that adding oxygen to burn fuel changes the composition of the atmosphere in the glassmaking furnace. [ABSTRACT FROM AUTHOR]

Modern methods and systems for monitoring the redox balance in glass as a key parameter for stabilizing the glassmaking process and attaining reproducible prescribed functional properties of glass and glass articles are examined. It is shown that the value of the trichromatic characteristics — the dominant wavelength, purity, and brightness of the color — must be used to monitor the light protection function of glass. [ABSTRACT FROM AUTHOR]

The results of IR spectroscopy of boric and silicic acids, which are the main components of the batch for fabricating microspheres, are presented. It is proved that the structure of boric and silicic acids contain water in molecular form (crystal-hydrate) and as OH groups, respectively. A formula is given for calculating the absolute degree to which the bands differ with respect to wave number and intensity. It is shown that half of the spectral bands of both acids can be used only conditionally to indentify the acids, and almost a third of these bands are the main (strongest) bands. The bands at 1195 cm−1 in the spectrum of boric acid and 1180 and 1200 cm−1 in the spectrum of silicic acid are indistinguishable with respect to position and intensity and cannot be used for analysis. The wave number is a necessary and sufficient indicator for identifying the acids in the mix, but in the case of the conditionally used bands analysis of a mixture of acids is impossible if their intensity is neglected. [ABSTRACT FROM AUTHOR]