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The possibility of using quartz sands from the Oinakum deposit as a promising source of high-quality quartz-containing raw materials for the glass industry in order to obtain higher grades of glass is considered. The chemical, granulometric, and mineralogical compositions of quartz sands of the Oinakum deposit were investigated; different enrichment schemes were used to obtain high concentrations of quartz sand. [ABSTRACT FROM AUTHOR]

Anew polyfunctional heat-resistant coating for protection from high-temperature gas corrosion (up to 900°C) swas synthesized based on glass in the system BaO–B2O3–SiO2. The synthesized heat-resistant polyfunctional coating has enhanced resistance to high-temperatures and high dielectric properties, thereby making it polyfunctional. The high level of the properties is afforded by a composition that is based on refractory glass and by the introduction of a coupling activator. [ABSTRACT FROM AUTHOR]

Bismuthate-borate glasswas synthesized with the compositions (wt.%) 70 Bi2O3, 2 GeO2, 25 B2O3, 3 MoO3; 70 Bi2O3, 17 GeO2, 10 B2O3, 3 MoO3 and 80 Bi2O3, 4 GeO2, 5 MoO3, 11 SiO2; 80 Bi2O3, 8 GeO2, 8.5 SiO2, 3.5 MoO3. Methods were developed for forming a receptor layer on the resulting glass by means of ultrasonic spraying of the interacting components and applying a water-insoluble polymer film obtained via a chemical reaction between the polymer poly-N,N-dimethyl-3,4-dimethylenepyrrolidinium chloride and the modifier potassium hexacyanoferrate (II). The sensors prepared based on these glasses make it possible to determine to within2– 4% the content of hydrogen sulfide and water vapor in air. [ABSTRACT FROM AUTHOR]

This articles discusses the use of 20Kh23N18T mark stainless steel and its foreign analogue AISI 310S instead of 12Kh18N10T steel as a material for making shaping dies used in the manufacture of glass insulators made from S93-3M mark electrovacuum glass. Such insulators are widely used in the radio-electronic industry as housings for magnetically operated contacts. It is shown that at operating temperatures a chemical interaction occurs between both grades of steel and S93-3M grade glass, which results in deterioration in the product quality on account of the appearance of a large number of gas bubbles in the product. It was ascertained that the additional heat treatment makes it possible to diminish the consequences of this chemical interaction, and thereby improve the quality of the resulting product. [ABSTRACT FROM AUTHOR]

The formation of micro-scale tracks in the bulk of porous glass samples using femtosecond laser pulses was investigated, which is of interest for laser writing of active optical waveguides. It was ascertained that the impregnation of nanoporous glass with a bismuth nitrate solution effects the appearance of an orange luminescence band on excitation at 488 nm, which is intensified in the formed tracks. It is demonstrated that increasing the laser pulse energy to 200 nJ makes it possible to increase the phase contrast for tracks written in nanoporous glass containing bismuth, compared to tracks recorded in additive-free nanoporous glass. [ABSTRACT FROM AUTHOR]

The effect of a small addition of CeO2 on the process of thermally stimulated formation of Au plasmonic nanoparticles in ZnO–MgO–Al2O3–SiO2 glass containing the crystallization catalysts TiO2 and ZrO2 was investigated by means of absorption spectroscopy, differential-scanning calorimetry, and x-ray diffraction analysis. It is shown that on heating glass from temperatures slightly above Tg up to temperatures near the exothermic peak the plasmon resonance band of nanoparticles undergoes a nonlinear shift, but the addition of CeO2 substantially expands the shift zone to the long wavelengths of the spectrum. Computer modeling of the experimental absorption spectra was performed, the sizes of the formed nanoparticles were calculated, and a mechanism whereby adding CeO2 effects the formation of plasmonic Au nanoparticles is proposed. [ABSTRACT FROM AUTHOR]

The highlights of the 24th International Exposition Glass World held in Moscow are briefly cited. About 100 companies from 12 countries of the world participated. New manufacturing and quality-control technologies of glass products and the main structural components of glass furnaces and methods of their high-quality production are demonstrated at the exposition. Examples of the most successful enterprises in the glass industry are given. [ABSTRACT FROM AUTHOR]

Hollow glass microspheres were obtained from soda-borosilicate glass by a high-temperature method, weight content, %: 10 Na2O; 8 CaO; 0.3 MgO; 0.2 Al2O3 ; 9 B2O3 ; 0.5 SO3 ; 72 SiO2. It was ascertained that the maximum yield of microspheres, up to 87%, is observed on use of a propane–air torch with the following characteristics: air/propane ratio 1.3; maximum temperature on the flame axis 1900°C; opening angle about 15°; and, flow rate of carrier gas 0.2 g/sec. The hollow glass microspheres obtained in this regime are characterized by median diameter 60 μm, average wall thickness 1.3 μm, bulk density 260 kg/m3, and calculated strength 50 MPa. [ABSTRACT FROM AUTHOR]

Curves of full x-ray scattering at wavelength 0.20735 Å were measured and the corresponding radial distribution functions (RDFs) of the electron density for glasses in the systems La2O3–Nb2O5–B2O3 and BaO–Nb2O5–P2O5 were separated out. Peaks indicating the presence of a pronounced medium-range order in the glasses under study are clearly observed in the RDF at distances up to about 1 nm. Consideration of the RDF shows that for the BaO–Nb2O5–P2O5 glasses with high BaO content, the medium-range order manifests in the form of chains of barium polyhedra that do not lie in the low-index planes of an ideal BaO crystal. For the La2O3–Nb2O5–B2O3 glasses, chains of lanthanum polyhedra are observed, which are similar to polyhedra in the LaB3O6 crystal linked via borate groups. In the considered glasses of both systems, niobium polyhedra do not form extended chains. [ABSTRACT FROM AUTHOR]

A new glass-filler for dental composites has been developed based on glass in the system SrO–Al2O3–B2O3–SiO2. This filler meets contemporary requirements for filling materials and is characterized by high chemical resistant to water, acids and alkalis (Class I), high visible-range transparency (> 80%), and CLTE-compatibility with the polymer matrix. The melting temperature is acceptable, and crystallization is not a proclivity. It is shown [demonstrated that the new glass filler effects high-level medical-biological, operational, and functional properties of the dental composite based on it, and competitiveness with respect to the popular foreign-made analog materials. [ABSTRACT FROM AUTHOR]

Glass in the system SiO2–Al2O3–SrO–P2O5–F with phosphorus oxide content 7 – 12 mol.% was obtained. The combination of properties of the resulting glass (refractive index 1.514 – 1.535, CLTE 44 × 10 –7 – 61 × 10 –7 K – 1, transmission > 85%, radio-opacity ≥ 300%), together with the ease of the synthesis process (melting temperature < 1500°C), indicates that such glass holds promise for use as a filler in glass ionomer cements for dentistry. [ABSTRACT FROM AUTHOR]

A resource- and energy-saving technology for using foam paints to decorate manufactured glass articles was developed. The optimal parameters for firing the coating by a plasma-forming argon-gas flow were determined. The effect of sodium liquid glass on the quality of a decorative coating was investigated. [ABSTRACT FROM AUTHOR]

A method of eliminating gaps between heat bonded glass plates has been developed using a system for distributing mechanical load. The proposed method was investigated theoretically and experimentally. The results of numerical and full-scale model experiments confirming the efficacy of the proposed method are presented. [ABSTRACT FROM AUTHOR]

New glassy materials in the system ZnO–B2O3:CoO system were obtained. The physicochemical and spectral properties of zinc borate glass doped with cobalt in the composition range 45 to 70 wt.% ZnO. The influence of the glass matrix on the coordination state of Co2+ ions is shown. Intense absorption bands in the visible range are attributed to the transitions 4A2(F) → 2A1(G), 4A2(F) → 4T1(P), and 4A2(F) → 2E(2G). An absorption band attributable to the electronic transition 4A2(4F) → 4T1(4F) of cobalt in tetrahedral coordination was found in the near-IR range (1.3 – 1.7 μm). [ABSTRACT FROM AUTHOR]

The results of an investigation of the basic indicators of cobalt-containing metallurgical wastes for use as a substitute for scarce expensive cobalt oxide in the production of colored sectional glass and ground glass enamel are presented. The chemical, mineralogical, and granulometric compositions were established experimentally, and a processing technology with Co3O4 36.45 wt.% released in a concentrate was proposed. The addition of this oxide made it possible to obtain blue glass, which confirms the applicability of cobalt-containing waste as a replacement for pure cobalt oxide. Likewise, experiments were performed to assess the possibility of using these wastes in obtaining glass enamel and physicochemical methods were used to investigate the obtained samples and the optimal conditions for obtaining cobalt oxide and its obtained amount as a chromophore and adhesion activator in the glass-enamel–metal system were determined. [ABSTRACT FROM AUTHOR]

The results of studies of chemical, x-ray phase, microscopic, electron microscopic, and granulometric analyses as well as the technological properties of quartz sand from the Tamdin deposit are reported. It was established that this quartz sand can be used in industrial enterprises of Uzbekistan as a promising source of high-quality raw materials for the production of glass and glass-ceramic materials for technical, household, and construction purposes. [ABSTRACT FROM AUTHOR]

The possibility of lowering the energy costs of scribing glass and ceramic plates is investigated in the context of the one-dimensional problem of evaporation of an absorbing layer of a material with 'instantaneous' release of the energy in a laser pulse. A scribing method is proposed, where in the laser radiation emitted through the back surface of a tile is returned to the tile with the help of a mirror with reflection coefficient about 99%. The optimal tile scribing regimes are determined. It is shown that with deep scribing energy costs can be 1.4 – 1.8 times lower compared with conventional laser scribing. For scribing groove depths less than 0.3 times the tile thickness, the considered method is inappropriate because the positive effect is very small. [ABSTRACT FROM AUTHOR]

Substrates for enhancing the giant Raman signal (SERS) of light are being actively developed for the purpose of accurate detection of low concentrations of organic molecules. However, the complexity and high cost of fabricating substrates often limit their application. A simple method for obtaining SERS substrates based on nanoporous glass functionalized by means of silver particles is proposed, and the efficiency of the substrates in detecting low concentrations of benzoic acid is demonstrated. [ABSTRACT FROM AUTHOR]

This article reports the results of a physicochemical investigation of the high-temperature sintering process and solid-phase reactions in a ternary composition based on Koitash quartzite, Angren clay, and Karakhtai limestone for obtaining unshaped dinas refractory materials. These processes were found to effect chemical interactions by way of solid-phase reactions and, on participation of a liquid phase, with the formation of highly basic aluminosilicate minerals with high refractoriness and strength as well as low porosity, which are reflected in the production of unshaped refractory materials with improved physicomechanical and technological properties. [ABSTRACT FROM AUTHOR]

The influence of the spheroidization process occurring in 1.0 mol.% Nd2O3 doped Li2O–Al2O3–SiO2 (LAS) glass in a high-temperature plasma flow on the properties of glass crystallization was investigated. The resulting 32 – 64 μm microspheres are characterized by a significantly higher glass transition temperature Tg compared to that of the original glass, which could be associated with both a change in the chemical composition on spheroidization and a fundamentally different thermal history of the microspheres and glass. In spite of the moderation of the crystallization kinetics, in microspheres as well as in the original glass, under the influence of heat treatment, a glass-ceramic structure is formed based on â-eucryptite-like solid solutions LixAlxSi1–xO2, indicating the possibility of obtaining microspheres with glass-ceramic structure as well as varying their linear thermal expansion coefficient near zero values. [ABSTRACT FROM AUTHOR]

The crystallisation kinetics and effects of doping on Bi2Sr2CaCu2Oδ (BSCCO) glass ceramic system with 0.0%, 0.1%, 0.3% and 0.5% PbSe were investigated in this study. Differential thermal analysis (DTA) was used to investigate the effects of PbSe doping on glass transition, nucleation and crystallisation temperature of glass were investigated. The DTA results were analysed using the Ozawa, Augis–Bennett, Takhor and Kissinger equations for nucleation kinetics to determine the activation energies and Avrami parameters. Thermogravimetric analysis revealed that the amount of oxidation in the structure increased with increasing PbSe-doping concentration. [ABSTRACT FROM AUTHOR]

The results of the synthesis of lanthanum borate glasses modified with highly polarizable cations (Nb, Ti, Zr, Ta) are described, their crystallization properties were studied, and their structural features were investigated by means of IR spectroscopy. It was determined that glass blanks with refractive index > 1.8 can be obtained in the composition range 25La2O3–xMnOm–(75 – x)B2O3 (M = Nb, Ta, Ti, Zr, x = 5 – 25 mol.%). It is proposed that a network of large polyhedra of the modifying cation, which are bound at the vertices, is formed in addition to the borate network, thereby allowing the melt to retain its glass-forming ability. [ABSTRACT FROM AUTHOR]

The particularities of the preparation of glass batch containing selenium for making colorless glass and bronze-colored heat-absorbing glass are examined. Methods are proposed for reducing the volatilization losses of selenium on conveyance of batch and during glass melting. The possibility of using diatomite and soluble sodium silicate for these purposes was investigated. [ABSTRACT FROM AUTHOR]

Enamel coatings for protecting ozonizer electrodes were obtained in the system PbO–B2O3–Sb2O3–SiO2 with variable content of silicon oxide and antimony oxide. The results showed that enamel with antimony oxide content 5 wt.% possesses the best combination of thermal, thermomechanical, and electrical properties in combination with the required covering power. [ABSTRACT FROM AUTHOR]

The effect of added Al2O3, introduced by the substitution method, on the crystallization and spectral-luminescent properties of gallium germanosilicate glasses with γ-Ga2O3:Ni2+ nanocrystals was investigated. It was found that the Ni2+-luminescence efficiency increased on account of both an increase in the degree of crystallinity of glass with Al2O3 and an increase in the strength of the crystal field around the Ni2+ ions on account of Al3+ incorporation into the structure of the precipitated nanocrystals. [ABSTRACT FROM AUTHOR]

The effect of added Al2O3, introduced by the substitution method, on the crystallization and spectral-luminescent properties of gallium germanosilicate glasses with γ-Ga2O3:Ni2+ nanocrystals was investigated. It was found that the Ni2+-luminescence efficiency increased on account of both an increase in the degree of crystallinity of glass with Al2O3 and an increase in the strength of the crystal field around the Ni2+ ions on account of Al3+ incorporation into the structure of the precipitated nanocrystals. [ABSTRACT FROM AUTHOR]

The advantages of alkoxy technology as a type of sol-gel method of synthesizing ceramics and glass-ceramics are shown, and the methods for synthesizing alkoxides and oxides based on them are reviewed. The results of experimental research on the production of mullite glass-ceramics by means of alkoxy technology are described and the structural and phase transformations of the intermediate product formed during the synthesis of mullite are studied. [ABSTRACT FROM AUTHOR]

The influence of calcium fluoride, zinc oxide, and boron oxide as modifying additives on the melting and crystallization properties of strontium aluminosilicate glasses is examined. The influence of the type and amount of the modifying additive on the homogeneity of the molten glass and the quality of glass castings was evaluated visually. Bulk crystallization and XRD were used to study the effect of additives on the formation of the crystalline structure of the glasses. [ABSTRACT FROM AUTHOR]

The problem of determining the strength of cylindrical ceramic parts on punching holes in them is examined within the framework of the theory of developed evaporation of matter by laser radiation. Analytical relations are obtained for calculating the power density of laser radiation, leading to the destruction of the lateral surface of parts by the pressure of gaseous products as a function of the ratio of the hole radius to the part radius, the ratio of the part radius to the radius of the hole in the part, and the thickness of the lateral surface of the part as a function of the power density of the acting laser radiation. The applicability of the results obtained for determining the strength of cylindrical parts is shown for the example of P-25 technical ceramics based on magnesium oxide. When the ratio of the hole radius to the part radius is less than 0.3, the part can be considered as an infinite body. In this case the computational error will not exceed 10%. [ABSTRACT FROM AUTHOR]

Organo-inorganic hybrid materials based on inorganic oxyfluoride lead-borosilicate glass matrices and the metal-complex compound tris-(8-oxycholate) ytterbium (III) were obtained by the melt method. The spectral-luminescence properties of tris-(8-oxycholate) ytterbium and hybrid materials in the visible and IR ranges were studied under different excitations (377 and 785 nm). It is shown that the intensity of IR luminescence in the initial metal-complex luminophore surpasses the luminescence in the visible range and vice versa in the obtained hybrid materials — the intensity of visible luminescence significantly surpasses the IR-luminescence. [ABSTRACT FROM AUTHOR]

The bonding strength of an enamel reaction-cured coating on the heat-resistant nickel alloy VZh171 was investigated by means of sclerometry. The threshold load required for cracks to appear in a coating was determined. The values obtained are high for this type of material and correspond to the level typical for chromium and nickel coatings. The results of a microstructural analysis of the tested samples are also presented. The defects arising in each incremental load zone are described in detail. [ABSTRACT FROM AUTHOR]

It is demonstrated that a femtosecond laser beam forms birefringent nanogratings in the bulk of sodium aluminoborate glass. The dependence of the phase shift of the light passing through the nanogratings on the parameters of the laser radiation and the chemical composition of the glass is determined. It is shown that an increase in the Al2O3 content at constant molar ratio [Na2O]/([B2O3 + Al2O3]) has no effect on the laser exposure parameter intervals where nanogratings are formed but does effect an increase in the phase shift in them. [ABSTRACT FROM AUTHOR]

The results of studies on lowering of the melting temperature of strontium aluminosilicate glass by introducing boron and phosphorus oxides into the batch are reported. The main physicochemical processes occurring in the batches on and heating and the sequence and temperature intervals in which they occur were determined. [ABSTRACT FROM AUTHOR]

The results of experimental studies of the transmission of 12 and 15 keV electron beams through tapered glass macro-capillaries are presented. Measurements showed that there is no explicit dependence of the output current on the electron energy. The time dependence of the beam current at the output from the capillaries was measured. [ABSTRACT FROM AUTHOR]

The formation of polarization-dependent birefringence, apparently due to the formation of nanogratings, in the bulk of lithium silicate and lithium aluminosilicate glasses under the action of a series of femtosecond laser pulses was demonstrated. The phase shift in the light passing through the modified regions was determined as a function of the parameters of the laser radiation and the chemical composition of the glass. It is shown that Al2O3 content growth due to the presence of an alkaline component in the glass composition effects an increase in the minimum number of pulses required for the formation of a birefringent region as well as an increase in the retardance. [ABSTRACT FROM AUTHOR]

The effect of alkali treatment on the breakdown process and some surface characteristics of machined glass disks of lead-silicate glasses C87-2 and C78-4 was investigated. It is shown that the interaction of these glasses with barium hydroxide effects the removal of silicic acid from the gel surface, which in turn improves the wettability by water and the optical transparency of the glasses. In the manufacture technology of electro- vacuum devices, where lead-silicate glasses are used, it is proposed that the glasses be washed with barite water for fast coagulation of silica gel, which excludes the appearance of foreign particles on the surface of the investigated glasses. [ABSTRACT FROM AUTHOR]

Transparent glass-ceramic materials co-activated by Eu3+/Gd3+ were obtained by heat treatment of the initial lead fluoroborate glasses. It was found that the rare-earth ions in the obtained transparent samples are located in nanoparticles of lead fluoride cubic crystals, distributed in the bulk of the glass. It was shown that Eu3+ ions are situated in a highly symmetric local environment and that the introduction of a second activator increases the nanocrystalline phase fraction. [ABSTRACT FROM AUTHOR]

Analytic relations for calculating the energy density needed to punch holes through optically thick nonmetallic materials are derived for several variants of the action of the laser radiation within the scope of the one-dimensional problem of the vaporization of the absorbing layer of matter with 'prompt' deposition of the energy of a laser pulse. Analytic relations are derived for calculating the vaporized mass of material per unit energy input. A comparative analysis is made of the variants of the laser action on a plate, showing that the energy consumption in punching holes through optically thick glass and ceramic plates can be decreased. [ABSTRACT FROM AUTHOR]

A method of producing ceramics from igneous rocks is presented for the example of gabbro. It is shown that potassium liquid glass can be used as a binder. The method of physicochemical modeling was used to calculate the mineral compositions of the components formed on heating the gabbro. The optimal conditions (dispersion of the powder, amount of binder, and so forth) of the process under consideration were determined. Ceramic samples were obtained and their basic properties determined. [ABSTRACT FROM AUTHOR]

Selective quality control of manufactured multilayer windshields was conducted. Deviations of curved products from a specified shape were brought to light. Linear regression models describing the dependence of sagging of the glass on the curving temperature were devised. Simulation modeling of the algorithm controlling the curving process shows that the quality of the manufactured laminated glass can be improved. [ABSTRACT FROM AUTHOR]