Glass and Ceramics最新文献

The present article describes a method for determining the physico-mechanical properties of a synthesized batch of proppants. Industrial waste is one of the sources of anthropogenic impact on the environment on a global scale, being formed in the process of coal and oil extraction as a by-product.With the decrease in stocks of high-quality natural raw materials and the accumulation of man-made products, the problem of waste utilization becomes urgent.

The possibility of isovalent substitution of zinc and cobalt atoms in the structure of willemite Zn₂SiO₄ was studied. Ceramic pigments with a willemite structure of blue, violet, and light blue colors were synthesized. Samples of blue color were used in the manufacture of glazes. During the synthesis of the pigments, synthetic silicon oxide was replaced by natural quartz sand. The pigments were synthesized by solid-state method at a temperature of 1270°C. The physical and chemical properties of the synthesized blue pigment were determined. In addition, the pigment was tested for use in traditional glazes for the coloring of ceramic products. It was established that the obtained blue pigment provides high aesthetic and decorative characteristics at a relatively low price.

High-temperature insulation materials are used extensively in civil engineering as flame retardant materials, as well as in numerous industrial sectors. The raw materials used in the production of these materials include rocks and industrial waste. The article substantiates the feasibility of using ceramovermiculite and ceramoperlite materials containing a wollastonite binder as high-temperature insulation. The materials were obtained through the firing of a charge containing chalk, diatomite, and a heat-resistant filler (expanded perlite or expanded vermiculite). The material of the fired samples with expanded vermiculite is primarily composed of the crystalline phase of wollastonite and biotite, with a minor amount of quartz and akermanite-gehlenite. The use of expanded perlite as a heat-resistant filler results in the presence of a low amount of plagioclases in addition to the crystalline phase of wollastonite in fired samples, along with an amorphous phase. The physicomechanical properties of the charge and the fired samples were determined, and the effect of the apparent density and phase composition of the developed materials on the variation in their thermal insulation properties at high temperatures was studied. The thermal insulation properties of the materials were determined by supplying heat flow from the heating chamber of the muffle furnace to one side of the sample. The samples from the developed materials exhibited apparent densities ranging from 375 to 630 kg/m³ and compressive strengths between 0.95 and 3.25 MPa. The developed ceramoperlite materials containing wollastonite binder can be used as high-temperature thermal insulation up to +900°C, while ceramovermiculite can be used up to +1050°C. According to a range of physicomechanical and thermophysical properties, the materials obtained are comparable to or exceed the performance of known analogs.

This review presents various interpenetrating phase composite (IPC) materials currently used in computer-aided design/computer-aided manufacturing (CAD/CAM) systems and to evaluates how the optical properties of those materials are affected by various factors. In the field of dentistry, selecting materials compatible with dental tissues is key to clinical success of restorative materials. Understanding the optical properties of a restorative material aids in material selection and provides insights into the material’s clinical performance and esthetic longevity. Such knowledge can in turn help clinicians select the best treatment option for their patients. Interpenetrating phase composite materials combine the optical and mechanical properties of ceramics and composite resins; they are often used in direct/indirect restorative options such as inlays, onlays, veneers, single crowns, implant-supported crowns, and short-span fixed partial dentures with esthetically favorable outcomes. The color of a material, which plays an essential role in the esthetic outcome, can change over time depending on different intrinsic and extrinsic factors. Those intrinsic factors include chemical composition, resin-matrix structure, and filler particle sizes; extrinsic factors include surface treatment protocols, the patient’s smoking status, and the consumption of beverages such as coffee, tea, red wine, fruit juice, cola, etc. To fabricate restorations that complement a person’s natural teeth, it is essential to determine the color properties of these materials (e.g., translucence, hue, chroma, and opalescence).

A mathematical model was developed for the calculation of thermal processes occurring in hexagonally located cells in the form of connected channels with a filler. The proposed model was used to calculate the temperature fields and power of heat flows along a single homogeneous long thin rod of calcium carbonate perovskite embedded in the hexagonally arranged channels of anodic aluminum oxide. In addition, the equations for calculating the distribution of temperature and power of heat flows in the wall of the aluminum oxide channel in the perpendicular direction were derived. The resulting calculations can be used to develop advanced highly efficient solar power electronic devices.

The purpose of the study was to develop compositions of colored glasses based on basalt from the Osmonsay deposit. To synthesize glasses, compositions based on the basalt – quartz – soda lime system were studied. Quartz sand from the Samarkand deposit was used as a source of quartz. Transparent, translucent, and opaque colored glasses were obtained. The research demonstrated that it is possible to obtain glass of a wide range of colors without the use of coloring components.

The direct femtosecond laser writing of phase optical elements in glasses represents a promising technique for controlling light beams and developing new functional devices that operate on the birefringence effect. In this study, phase plates were written in the volume of silica and nanoporous glasses using a laser beam. For the first time, the chromatic dispersion curves of birefringence were measured for such plates using multiple methods. This allows the retardance of birefringent elements fabricated by direct laser writing to be estimated, even when using commercial birefringence analysis systems operating at a specific wavelength.

The study is devoted to the development of composite materials for the production of ceramic bricks based on loess-like rocks from the Suzanly deposit and waste produced by Khorazm Shakar LLC. The study examines the physical and chemical processes during firing with the introduction of amorphous silica and calcium-containing waste (beet lime) in the brick mass. The technological firing modes were determined. The objective is to develop optimal compositions of special ceramic bricks and masonry mortars for the inorganic parts of cultural heritage sites, based on local raw materials and industrial waste.

The preliminary results of experimental modeling of the impact process on a coal substance by short-pulse laser radiation are presented. During the experiments, extremely high temperatures and pressures were reached. Based on the analysis of the modified products of the target substance, coal melting was identified, followed by its cooling with subsequent solidification with the formation of glass-like carbon. The synthesis products may be of interest as novel carbon materials formed at ultrahigh pressures and temperatures, such as high-pressure carbon polymers and hollow fullerene-like structures. The results of experimental modeling can be used for comparison with naturally occurring materials in order to elucidate the mechanisms of the formation of natural high-pressure carbon substances from a non-graphite precursor.

Within the scope of the study, glasses co-doped with Sm³⁺/Gd³⁺ based on the B₂O₃–GeO₂–Bi₂O₃ system were synthesized, covering compositions of 40B₂O₃–40GeO₂–(15 – 17)Bi₂O₃–(3 – 2)Sm₂O₃–(2 – 1)Gd₂O₃ and 42.5B₂O₃–42.5GeO₂–(11.25 – 12.75)Bi₂O₃–(2.25 – 1.50)Sm₂O₃–(1.500 – 0.075)Gd₂O₃. An assessment of luminescent characteristics was carried out within the temperature range of 298 – 673 K. Spectral bands of photoluminescence associated with transitions between various Stark sublevels of Sm³⁺ ions were identified. Redistribution of the fluorescence intensity ratio corresponding to ⁴G_5/2 → ⁶H_9/2 (({uplambda }_{mathrm{PL}}^{mathrm{max}}) = 645 nm) and ⁴G_5/2 → ⁶H_7/2 (({uplambda }_{mathrm{PL}}^{mathrm{max}}) = 597 nm) transitions was observed. Based on the obtained data, calculations of the fluorescence intensity ratio FIR, as well as relative sensitivity S_R, were carried out. The obtained results indicate the promising potential of these glasses as luminescent thermometric materials.