Kozlovskiy A.L., Zdorovets M.V.
STUDY OF PHASE TRANSFORMATIONS IN FERROELECTRICS BASED ON CALCIUM TITANATE.
The aim of this work is to study phase transformations kinetics in ferroelectrics based on calcium titanate. The relevance of this study is in the assessment of new methods for obtaining complex phase composition ferroelectrics, which have the potential for application in microelectronics, photocatalysis, and power engineering. The methods of scanning electron microscopy and X-ray diffraction were used as the main methods of analysis. Analysis of morphological features made it possible to establish the kinetics of changes not only in grain sizes, but also in their geometry. During the studies of phase transformations, the following dependence of the TiO2 – anatase/CaTi2O4 → TiO2– anatase /CaTi2O4/CaTiO3 → CaTiO3/TiO2 – rutile type was established depending on the annealing temperature. At the same time, at a temperature of 1000°C, a stable structure of ceramic with a perovskite-like structure of the CaTiO3 type and a high structural ordering degree (more than 92%) is formed.
Stary O., Surzhikov A.P., Маlyshev A.V., Lysenko Е.N., Sheveleva E.A.
EFFECT OF NORMALIZING HEATING OF FERRITE COMPACTS ON COMPACTION DURING RADIATION-THERMAL SINTERING.
The study investigated linear shrinkage of lithium-titanium ferrite samples during radiation-thermal and thermal sintering. Prior to compaction, part of the powders were subjected to thermal heating for 2h at temperatures of 1273, 1373, and 1473 K. It is found that changes in the shrinkage kinetics of ferrites after powder annealing are consistent with the classical concepts of thermal deexcitation of powders due to annealing of defects. Such defects were formed in powder grains during grinding. The obtained data analysis allowed us to offer the most likely model for radiation-thermal activation of powder ferrite sintering. This is a model of radiation inhibition of non-equilibrium defects relaxation.
Yurov V.M., Goncharenko V.I., Oleshko V.S., Sha Minggong.
ANISOTROPY OF THE SURFACE OF CARBON MATERIALS
In this work, a model of the surface layer of perfect single crystals is used and the role of surface energy in physical processes occurring in the region of nanosized carbon materials is clarified. Of these, diamond, graphite, carbyne and fullerenes have been investigated. The thickness of the surface layer of diamond with cubic symmetry is 8.2 nm and is a nanostructure. The average size of the synthesized nanodiamond is of the order of ~ 8 nm. The value of the surface energy σhkl calculated by us along the diamond planes (100), (110), and (111) is in good agreement with experiment and other calculations. The thickness of the surface layer of graphite along the a axis is equal to R(I)a = 8.0 nm and also represents a nanostructure. But along the c axis we have a layer thickness of about 1.5 nm and the number of monolayers is only 2. On this c axis, graphite can be created a monolayer by turning it into graphene. The σhkl value calculated by us along the a and c planes of graphite is 25957 and 5515 mJ/m2, respectively. Carbines represent a polymeric polyyne or cumulene chain composed of sp-hybridized
carbon atoms. If we imagine that the thickness of the surface layer of carbyne is stretched into a one-dimensional chain along the c axis, then the length of this chain is up to 200 nm for α-carbyne. The thickness of the surface layer of fullerenes significantly exceeds the thickness of the surface layer of pure metals. The surface energy of fullerenes σhkl increases with an increase in the number of carbon atoms С36 → С96. It also changes in the series
(111) → (100) → (110).
Tlebaev K.B., Kurmanbaeva G.A.
MODIFICATION OF POLYTETRAFLUOROETHYLENE ON THE BASE OF ULTRAFINE POWDER
This paper presents the results of a study of the influence of thermal and mechanical effects on the formation of a structure in an ultrafine powder heated to a temperature above the melting point of polytetrafluoroethylene (327°C). The ultrafine powder was obtained by mechanical grinding of an industrial sample of polytetra-fluoroethylene in a rotary knife mill. Studies of the ultra powder with a transmission microscope showed that the powder particles are quasi-spherical particles of a size of 5 microns. The thermal (sintering, slow and fast quenching) and mechanical (creation of high pressure) effects on ultrafine powder particles were determined by the methods of an automated digital microscope Leica DM 6000, X-ray diffraction, and Vickers. It was found that the formation of a supramolecular structure depends on the applied force (pressure) and temperature. Measurement of the hardness of the modified sample showed that its hardness in relation to the hardness of the industrial sample increased by 4 units.
Rakhadilov B.K., Sagdoldina Zh.B., Baizhan D.R.1,Zhurerova L.G., Yeskermessov D.K., Kalitova A. A.3, Smaiylova M.
OBTAINING OF HYDROXYAPATITE COATINGS ON A TITANIUM SUBSTRATE BY DETONATION-GAS SPRAYING
The article considers research results of the formation process of a hydroxyapatite coating on a titanium substrate during detonation spraying. Powders for sputtering and obtained coatings of hydroxyapatite were studied by Raman spectroscopy and X-ray structural analysis. It was determined that the appearance of α-tricalcium phosphatephase is characteristic of a pure hydroxyapatite coating obtained by detonation spraying. Still, the hydroxyapatite phase is retained in the coating composition. Results obtained by Raman spectroscopy indicate that hydroxyapatite is the main phase in coatings. The morphology of the sprayed coatings was characterized using scanning electron microscopy, and the coatings elemental composition analysis was obtained using an energy-dispersive spectrometer detector. Energy-dispersive spectrometer analysis showed that the elemental composition of the obtained coatings is similar to the elemental composition of the initial powder, which is very important for preserving the coatings services life.
Karipbayev Zh.T.1, Alpyssova G.1,2, Lisitsyn V.M.
LUMINESCENCE OF CERIUM DOPED YTTRIUM ALUMINUM GARNET CERAMICS SYNTHESIZED IN THE FIELD OF RADIATION FLUX
The paper presents the results of ceramic samples’ dependence of luminescent properties on their position in the crucible during irradiation. For the synthesis, a blend of powders of aluminum oxide, yttrium oxide and cerium oxide was prepared. The ratio of oxides in the charge corresponded to stoichiometric. The particles of the oxide powders had a size of about 1 micron and less. Synthesis was carried out on gas pedal electron accelerator at Institute of Nuclear Physics SB RAS (Novosibirsk). Luminescent properties were measured on spectrofluorimeter SM 2203 “SOLAR” under excitation by monochromatic radiation at 450 nm. Two types of samples differing in the value of bulk density and the prehistory of yttrium oxide were investigated..
LOCAL APPROACH FOR EVALUATING HEAT TRANSFER OF PRISMATIC ELEMENTS ON A FLAT SURFACE
Heat-exchange prismatic elements located on a flat surface are typical for many technical applications. The purpose of the work is to develop local approach for evaluating heat transfer of working surfaces based on local control of thermophysical parameters in characteristic zones of the working environment, using the methods of heat and mass analogy and hot-wire anemometry. The local approach allows more accurately diagnosing the types of flow in the boundary layer of a streamlined element and thereby, the temperature state of individual prismatic elements and the entire arrangement as a whole is determined more accurately. For calculating the local heat transfer of each face of the prism separately and the average surface heat transfer depending on the geometric and operating parameters equations of similarity are proposed.
Tanasheva N.K., Sakipova S.E., Minkov L.L., Bakhtybekova A.R.,Shuyushbaeva N.N., Burkov M.A.
STUDY OF AERODYNAMIC CHARACTERISTICS OF A CYLINDRICAL BLADE WITH DEFLECTOR
The article discusses some aspects of the renewable energy sources use, in particular, the problem of small wind power. A brief analysis of the development rates of wind energy in the world and in Kazakhstan is presented. The study is devoted to finding ways to optimize the blade of a wind power plant based on the Magnus effect, designed to generate electrical energy at low wind speeds. A cylindrical blade with a turbo-deflector has been developed to ensure independent starting of the blade rotation without the use of additional trigger mechanism. Laboratory tests of a cylindrical blade with a turbo deflector were carried out on a T-I-M wind tunnel at various flow regimes. The obtained dependences of aerodynamic forces on the air flow velocity at different angles of attack are shown..
Temirbekova M.N., Wójcik W.
POWER-GENERATING FUEL BASED ON THE PROCESSING OF MUNICIPAL SOLID WASTE ORGANIC COMPONENTS
The article considers effective technologies for processing the organic fraction of solid waste, involving the use of various approaches with the concept of preserving the ecology of the environment. Biomass cannot be simply collected and burned, the authors suggest using an effective method of its processing, which will allow fuel from it. To obtain energy, biomass can be used to produce biogas or liquid biofuels using various technological processes, for example, by fermentation. They, in turn, can be converted into electricity and heat, through combustion or the creation of fuel cells or used as fuel for motor vehicles. The purpose of this article is to use alternative methods, such as pretreatment of the organic fraction of municipal solid waste, ethanol fermentation with alcohol yeast, and anaerobic digestion are attracting increased attention. Using these methods, a liquid with alcohol-containing substances has been obtained from 1.5 kg of the organic fraction of municipal solid waste, in which the percentage of ethyl alcohol was 97.5%. Therefore, organic municipal solid waste can be a promising source of fuel in modern energy.
Bedych T.V., Shayakhmetov A.B., Omarov M.S., Isintaev T.I.
MOBILE PREMISES HEATING SYSTEM
In production and in everyday life, various heating systems are used. Alternative heating methods have also been used in recent years. One of the sources for the heating system is the Sun. The use of solar energy is of great importance for objects cut off from centralized heat and power supply systems: small villages and auls, farm formations, distant pasture breeding, mobile houses. Heating from the sun, created on the basis of solar panels, is carried out by installing an electric heater. Currently, more and more attention of consumers is drawn to the electrically conductive carbon-based fuel material (carbon). The aim of the study was to study the use of an alternative energy source in the form of solar radiation and carbon thermal flexible material as a heater for heating mobile living quarters of farmers. To carry out the research, a solar station and a heater with a carbon fiber heat-emitting flexible material were installed on the farmer’s mobile house. Studies have shown that the proposed system is efficient and in comparison with other systems, such as solar collectors, the system has a number of advantages.
Bekmuldin М.K., Skakov М.K., Baklanov V.V., Gradoboyev А.V., Akaev A.S.
HEAT-RESISTANT COMPOSITE COATING WITH A FLUIDIZED BED OF THE UNDER-REACTOR MELT TRAP OF A LIGHT-WATER NUCLEAR REACTOR
The paper is devoted to the analysis of existing options of under-reactor melt traps, designs and disadvantages of these traps. A variation of its own under-reactor melt trap with a heat-resistant composite coating with a fluidized bed is proposed. The description of facility for experimental studies of the heat-resistant composite coating with the fluidized bed is presented. The results of a thermal calculation of the variation of the under-reactor trap with fluidized bed melt are presented. Thermal calculations showed that an increase in the average temperature of the melt is less intense in the model of an under-reactor trap with a fluidized bed, due to heat removal from the corium to the metal to complete the phase transition.
Satybaldin A.Zh., Zhakipbaeyev B.Y., Tusipkhan A.1,Baykenov M.I., Khalikova Z.S., Alpyssova G.K.
THE INFLUENCE OF A HIGH-VOLTAGE DISCHARGE ON THE OIL BOTTOM SEDIMENTS FORMED AT THE OIL STORAGE FACILITIES OF THE ATASU-ALASHANKOU STATION
From three to ten per cent of the total oil produced can ultimately not be used for further processing. When the oil is transported by oil pipelines and oil tankers and stored in reservoirs, oil bottom sediments are deposited on the bottom comprising particles of mineral (non-oil origin) and the heaviest hydrocarbons, mainly paraffin series, whose specific gravity is higher than the density of oil and water. For reliable operation of the tanks, it must be periodically cleaned from the accumulated sediment. The study novelty is the use of the electrohydraulic effect for the processing of oil bottom sediments and creation of a waste-free technology for the disposal of oil bottom sediments in field conditions. The optimal mode for electrohydraulic impact, ensuring the destruction of bottom deposits of oil in the oil storage tanks of the Atasu-Alashankou station, is determined.
Abilmazhinov E.T., Akimzhanov A.Zh., Shaiakhmetov E.Y., Anibaev S.N., Nurgaliyev N.N., Shakerkhan K.O., Sailauov D.M.
DEVELOPMENT OF THE BIOGAS INDUSTRY AND PROSPECTS FOR THE IMPLEMENTATION OF BIOGAS PLANTS IN KAZAKHSTAN
The article provides an overview of biogas technologies abroad and in Kazakhstan, the experience of foreign countries in the biogas industry, the development and prospects for the introduction of biogas plants in the Republic of Kazakhstan for the environmentally friendly and profitable processing of organic agricultural waste, food production, processing enterprises. Recommendations are given on the specifics of the design of biogas plants in the difficult climatic conditions of Kazakhstan (especially in the north, east and central Kazakhstan). The current design of a biogas plant (filling volume 3.7 m3) is shown, in the design of which units of our own design were used, this is a peristaltic pump and a raw material grinder. The efficiency of a number of units, in particular a new design peristaltic pump, was shown in the course of the experiments.
Utepov Ye.B.1,2, Akhazhanov S.B.3, Aniskin A.4, Zharassov Sh.Zh.
EFFECT OF THE SHAPE AND STRUCTURE OF MATURITY SENSOR’S PLASTIC HOUSING ON ITS PHYSICO-MECHANICAL PROPERTIES
This paper presents how the shape and physical structure of the connections affect the performance of the housing of maturity sensor. A two parts rectangular and a keg-shaped cylindrical configurations of plastic housings were sequentially tested for water, shock and load resistance. The tests revealed the weak ingress and shock resistance of the rectangular housing, in comparison with cylindrical one, where no serious defects were identified. Both types of housings performed well during the compression tests on all three sides, showing the bearing capacities from 0.6 to 2.11 kPa, which are equivalent to 65.3 and 165.3 kg of human mass. Based on the results, the study demonstrates an easy-to-handle workflow for generic testing and evaluation of maturity sensors housing. The proposed workflow may be applicable for other types of small-scaled electronic devices
Kozlov E.A., Trubitsyn A.A., Fefelov A.A., Grachev E.Yu.
MODEL OF VOLUMETRIC HEAT SOURCES IN ANODE OF MICROFOCUS X-RAY TUBE
The work is developed a numerical-analytical approach to modeling thermal processes in a composite anode of microfocus X-ray tubes. At the first stage of modeling, with the help of well-known analytical approximations, the distribution function of volumetric heat sources is built. At the second stage, this function is used when solving a stationary boundary value problem with the Poisson equation by the Finite Elements Method. Using the proposed technique, an adequate assessment of the maximum power of the tube with the transmission type W-Be anode was developed.
Razina О.V.1,*, Tsyba P.Yu.1, Suikimbayeva N.
TACHYONIZATION COSMOLOGICAL MODEL IN THE FRAMEWORK OF LINEAR FORM-INVARIANCE TRANSFORMATIONS
This work dedicated to the investigation cosmological models based on tachyon field. It was showed that Einstein’s field equations for spatially flat, homogeneous and isotropic Friedman-Robertson-Walker space-time have form-invariance of symmetry, obtained by form-invariance of transformations. The form-invariance of transformations is specified in the general case by the linear function 𝜌̅=𝑛2𝜌, and in particular, we investigate for 𝑛=−1. The tachyonization of the cosmological model was made for the entire range of values of the barotropic index 𝛾. For the power-law function of the scale factor, a method for obtaining the potential and the function of the tachyon field was shown. The resulting potential is equivalent to the potential used in string theory