2020 YEAR
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№ |
The title of article |
Authors |
Year |
The name of journal |
Abstract |
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1 |
Refractive Index at Low Temperature of Tetrachloromethane and Tetrafluoroethane Cryovacuum Condensates |
Aldiyarov, A.U., Sokolov, D.Y., Nurmukan, A.Y., Ramos, M.A. |
2020 |
ACS Omega https://doi.org/10.1021/acsomega.0c00969
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We present low-temperature measurements of the refractive index of cryofilms of tetrachloromethane and 1,1,1,2-tetrafluoroethane at different condensation and measurement temperatures between 16 and 130 K. Using cryovacuum condensation, we have been able to obtain thin films in an amorphous state for both substances despite them being very bad glass formers. Then, we have studied the evolution of the refractive index with an increasing temperature, including by transitions to ordered or partially disordered crystalline states. Copyright © 2020 American Chemical Society. |
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2 |
The study of thermophysical properties of rubber and plastic household waste to determine the temperature conditions of cryoprocessing |
Aldiyarov, A., Sokolov, D., Nurmukan, A., Korshikov, E. |
2020 |
Applied Surface Science |
The effect of cryogenic treatment on the thermal characteristics emerged from the operation of automobile tires and plastic bottles of commercial beverages. Automobile tires manufactured according to the state standard “GOST 4754-97” (ISO 1043-1:2001 “Plastics – Symbols and abbreviated terms – Part 1: Basic polymers and their special characteristics”; ISO 11469:2000 “Plastics – Generic identification and marking of plastics products”; ISO 472:1999 “Plastics – Vocabulary”) and bottles made of polyethylene terephthalate for food liquids according to the state standard “GOST R 52789-2007” (ECE/TRANS/WP.29/GRB/2019/5 “Proposal for amendments to UN Regulation No. 30”) were used as the test samples. Temperature range of investigation was 95–300 K. The thermal conductivity measurements were carried out by a relative stationary heat flow method and the temperature change inside the samples with different forms on heating after cooling to nitrogen temperature. The results obtained are in good agreement with the literature data. |
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3 |
Investigation of vapor cryodeposited glasses and glass transition of tetrachloromethane films |
Aldiyarov, A., Nurmukan, A., Sokolov, D., Korshikov, E. |
2020 |
Applied Surface Science |
The vibrational spectra of CCl4 in the gas phase and in the condensed state were measured with a goal to compare them. The thickness of the condensed samples was d = 2.5 μm. It was shown that an increase in the temperature of the condensed sample leads to a change in the position of the absorption band. Based on the obtained dependence of the position of the absorption band on the temperature of the sample during its heating, an assumption is made that in the temperature range T = 16 K-T = 35 K the cryocondensate film is in an amorphous high density state. Experiments were conducted to determine the glass transition temperature (Tg = 79 K) in the sample by observing the half-width of the characteristic absorption band at a fixed frequency in the vibrational spectra versus temperature. |
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4 |
Application of Organic Fuel Additives to Enhance Coal Combustion Efficiency |
Messerle, V.E., Paskalov, G., Umbetkaliyev, K.A., Ustimenko, A.B. |
2020 |
Thermal Engineering |
The results from numerical and experimental investigations into the influence of organic fuel additives (OFAs) on the efficiency of combusting high-ash Ekibastuz coal are presented. Technology and a special combustion chamber equipped with a plasma-assisted startup system are proposed. The thermodynamic and kinetic parameters of cocombustion of coal with OFA are numerically analyzed, as a result of which the optimum process temperatures, air-to-coal mass consumption ratios, and combustion chamber geometrical parameters have been selected. Thermodynamic analyses of the coal combustion process have shown that 7 kg of air is required to burn 1 kg of coal. A tendency toward increasing the concentrations of CO2 and Н2О and, accordingly, toward decreasing the concentrations of NO, СО, and O2 in the coal combustion products in using OFA has been revealed. The kinetic analysis results have shown that the coal combustion process with a consumption rate of 10 kg/h is fully completed in a combustion chamber 0.2 m in diameter and 0.9 m in height. A series of experiments on cocombustion of Ekibastuz coal with OFA was carried out. The investigation results made it possible to evaluate the effectiveness of Omstar-DX1 and Open Flame OFAs, which are prepared as mixtures of light ethers. Comparative experiments of coal combustion with and without OFAs in different concentrations (0–5 cm3 per kg of coal) have shown that the OFAs increase the flame temperature in the combustion chamber’s initial part and decrease this temperature at the chamber’s outlet. This means that the air–coal mixture takes less time to ignite and, accordingly, it burns out more rapidly. The introduction of OFAs results in a noticeably more efficient combustion of low-grade coal, in smaller emissions of CO and NO, and in an increased concentration of CO2, which points to the more complete combustion of fuel. |