-
Details
-
Hits: 61
An overview of the applications of zirconium dioxide, partially stabilized with yttrium oxide, in various high-tech fields is presented. Particular attention is paid to its use in supercapacitors, where this material significantly increases the stability of devices during long-term cyclic tests, which is critically important for their practical application. In the field of solid oxide fuel cells, zirconium dioxide, partially stabilized with yttrium oxide, demonstrates exceptional characteristics, acting as an electrolyte, anode and membranes. When operating in the temperature range of 800...1000 °C, the material provides high ionic oxygen conductivity, which directly affects the efficiency of the entire fuel cell. In microelectronics, zirconium dioxide stabilized with yttrium oxide is used in the manufacture of thin-film transistors, where its outstanding dielectric properties and thermal stability become determining factors. This allows you to create reliable and high-performance electronic components. In the aviation industry and the production of gas turbine engines, zirconium dioxide, partially stabilized with yttrium oxide, is used as a heat-protective coating for hot path parts. The material demonstrates excellent resistance to extreme temperature loads, making it an ideal solution for protecting critical components. Various methods of applying such coatings, including plasma spraying and chemical deposition from the gas phase, are considered, as well as a detailed analysis of their characteristics, including layering, porosity, crystal structure of coatings and their thermal stability.
-
Details
-
Hits: 51
The article briefly describes the history of cooperation between the Glass and Ceramics magazine and the Department of Chemical Technology of Ceramics and Refractories at the Mendeleev University of Chemical Technology, which has been ongoing for over 90 years.
-
Details
-
Hits: 55
The article is a brief excursion into the history of long-term interaction of the “Glass and Ceramics” journal and the department of chemical technology of glass and glass-ceramics at the Mendeleev university of chemical technology.
-
Details
-
Hits: 64
The formation of micro-regions with altered refractive index in the volume of float and quartz glasses under the action of single femtosecond pulses has been studied. The phase distributions of the light passing through the micro-regions during observation along the recording direction and perpendicular to it are plotted. The influence of pulse energy on the magnitude of the phase change has been studied. It is established that the minimum energy of formation of micro-regions in the volume of float glass is lower than in quartz glass. The results obtained are of interest for creating analog sound carriers by modifying the glass structure with femtosecond laser pulses.
-
Details
-
Hits: 63
The processes of thermochemical hardening of aluminosilicate glass are investigated. The glass was processed in a KNO3 melt under industrial and laboratory conditions at 440…480 °C for 1…120 h. The effect of processing modes on glass properties was evaluated using Vickers microhardness measurement, spectrophotometry, magnetophotoelasticity to measure compressive stresses, and local birefringence analysis to determine the depth of the compressed layer, as well as X-ray fluorescence to evaluate cation exchange. The link between the temperature-time parameters of ion exchange and changes in glass’s structural, mechanical, and optical properties was revealed.
-
Details
-
Hits: 42
This paper presents a study of the possibility of synthesizing a thermal insulation material, sludge, based on oil production drilling waste. Samples of drilling mud were collected at the Komsomolskoye oil and gas condensate field and prepared for further use, including drying and milling. Its chemical and phase compositions were determined, confirming the possibility of using the waste for synthesizing thermal insulation materials. A series of raw materials for synthesizing sludge, as well as temperature and time modes of firing, were developed. A study of the physical and chemical properties of the synthesized samples was conducted. The optimal composition for synthesizing sludge was determined, which includes 80 % of drilling mud, 15 % of sodium hydroxide, 5 % of sodium tetraborate, 10 % of water, synthesized at a temperature of 1000 °C and having a density of 745.05 kg/m3.
-
Details
-
Hits: 49
Against the backdrop of globally tightened environmental regulations, particularly in the Russian Federation, conventional gas-cleaning methods (cyclones, bag filters, electrostatic precipitators) used in the glass industry are becoming insufficient. These are only effective for capturing suspended particles yet not capable of removing the gaseous marker pollutants at the required level: NOx, SO2, CO. The study is aimed at developing and experimentally validating a highly efficient integrated system that enables 90…95 % removal of gaseous pollutants and approximates 100 % removal of solid particles. A silica/mullite fiber-based reducing catalyst produced entirely from domestic materials (20 cm3) achieved 95 % NO conversion at 350 °C in laboratory reactor tests. The catalytic filter element (with a surface area of 0.02 m2) installed in the pilot setup showed high simultaneous removal efficiencies for multiple pollutants: NOx – 92 %, SO2 – 96 %, at an operating temperature of 380 °C. The authors proposed an integrated purification train that includes an acid-gas neutralization reactor, reagent-dosing systems (for lime, caustic solution, and ammonia water), an inertial separator, a ceramic catalytic filter unit, as well as lime and spent reagent silos. The study was conducted using the Ceramic Pulse-Jet Filter, T Modification, Catalytic Configuration laboratory and pilot testing unit (Bakor R&D Center).
-
Details
-
Hits: 68
The paper investigates the physical and technical properties of a composite material based on white-burning clay from the Kornilovsky deposit of the Tomsk region with the addition of a gas-forming agent. The physico-chemical properties of clay have been determined. The physical and technical properties of heat-insulating refractory products based on the white-burning clay of the Kornilovsky deposit have been determined. The applications of the material in industry with high-temperature technologies are proposed. The work is a continuation of the article “Investigation of the properties of clays of overburden rocks of the Kornilovsky deposit of the Tomsk region for use in the refractory, ceramic and petroleum industries”.
-
Details
-
Hits: 61
The effect of a combination of water-soluble magnesium and aluminum salts on the physicochemical properties of the obtained aluminomagnesium spinel was studied. It was shown that the formation of aluminomagnesium spinel occurs in the range of 800…1050 ? from synthesized xerogels based on different ratios of magnesium and aluminum chlorides and nitrates. It was found that the crystalline structure of the spinel is completely formed during heat treatment of xerogels from synthesized pairs of AlCl3 + MgCl2 salts at 900 °C and holding for 60 minutes, while they have smaller crystallite sizes compared to other heat-treated xerogels. It was revealed that a higher temperature of 1050 ? is required to obtain spinel from xerogels synthesized on the basis of pairs of Al(NO3)3 + MgCl2 and Al(NO3)3 + Mg(NO3)2 salts.
-
Details
-
Hits: 88
Yttrium aluminum garnet (YAG) powders were synthesized via chemical precipitation, both with and without the addition of ammonium sulfate as a dispersant. The impact of the dispersant on the particle size distribution of YAG powders calcined at various temperatures was investigated. Powder morphology was analyzed using scanning electron microscopy (SEM), revealing significant differences in both morphology and particle size depending on whether the dispersant was present. The kinetics of phase transformations in the ceramic powders, with and without ammonium sulfate, were thoroughly examined using X-ray diffraction (XRD) and simultaneous thermal analysis (STA). Based on the data obtained, a novel mechanism was proposed for reducing agglomeration in YAG ceramic powders through the use of ammonium sulfate as a dispersant. This mechanism entails the formation of intermediate phases, namely yttrium sulfate and yttrium oxysulfate, followed by their gradual decomposition to yield the garnet phase.
