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Introduction. Currently, the purification of wastewater and technological solutions by membrane methods is considered a promising way to neutralize liquid waste. Therefore, the task of developing an engineering method for calculating baromembrane devices is a challenge. Studies on methods involving calculation of design and process variables, membrane equipment design, research of technological features of membrane devices, selection of design schemes, as well as methods of strength and rigidity analysis, are investigated. Materials and Methods. Basic elements of the body of the combined membrane apparatus are considered, a design scheme is proposed, and a method for calculating the strength and rigidity of the main load-bearing element, the cover, is described. Results. The methods determine the required dimensions of shells and plates for the development of a combined membrane apparatus, and evaluate the strength properties of the devices of this class. The construction elements of the apparatus (primarily, the load-bearing covers) must meet not only the requirements of efficiency and quality of separation and cleaning of solutions, but also the conditions for safe operation. Therefore, the design of the device covers should be based on the optimal design dimensions (thicknesses of round plates, toroidal shells, and support rings). To test the method, the stress-strain state of the membrane apparatus structure was calculated for strength and rigidity. As an example, we consider one cover presented in the form of an open toroidal shell. The evaluation of the application of this technique, taking into account the fact that the shell is mated with a round plate in the inner diameter, and with a ring in the outer diameter, has provided the determination of the required parameters. Discussion and Conclusions. The obtained method of analytical description of the mechanical impact on the elements of the combined apparatus and the example of calculating the toroidal shell and plate, enables to evaluate the stressstrain state of the structure for strength and rigidity. The results of the calculation of covers made of various materials at different pressures are presented. Loading the combined apparatus with transmembrane pressure made it possible to determine the required dimensions of the shells and plates for its design and development.

The article is devoted to the development of an automatic method and device for monitoring the pressing of the stator core of a powerful turbo generator during its assembling at the manufacturer. The core is assembled and pressed in an upright position in separate parts; at each stage, it is necessary to monitor places with weakened solidity. The unevenness of the compaction density causes a relative displacement of the active steel sheets and losses of iron, as well as the appearance and development of certain defects (loosening of the teeth of the extreme packages, coloring of fragments of the active steel sheets, local closure of the sheets and heating of the packages), which can eventually cause severe accidents and failure of the turbo generator. Existing methods, including automatic ones, do not allow performing reliable monitoring. The method proposed by the authors for detecting places with weakened solidity is based on automatic measurement of the specific pressure of pressing during deformation of special control samples. A device for its implementation has been developed, which is a ring installed on the end surface of the core. Cells with control samples are evenly placed in the ring. The largest decrease in the sample thickness caused by the highest specific pressure corresponds to the smallest defect, and vice versa. As a pressure converter, it is proposed to use a flat metal membrane and a capacitive sensor with a digital output. The characteristics of the converter were calculated and experimentally verified. The specific pressure measurement results were processed using a special electronic unit. The device that has been developed makes it possible to improve labor productivity when monitoring the core, diagnose defects with greater reliability and eliminate them, and, ultimately, increase the reliability of the turbo generator as well as its durability.

The article studies examples of the use of innovative technologies in the field of “Smart City”, which is a key factor contributing to the implementation of the concept of “Smart City”. The paper presents various approaches to the implementation of information technologies, analyses case studies on the management of smart cities of the world, which justify the change in the approach from isolated vertical management to integrated holistic management. The study also analyses various examples of the use of innovative technologies and approaches in the context of “Smart City”, identifies the trends in their development. At the end, the authors carried out the analysis of the domestic experience of applying the concept of “Smart City” and the results achieved.

The analysis of scientific papers devoted to the mathematical description of electric generators of reciprocating motion with permanent magnets demonstrated that the proposed mathematical models of this type of generators are based on the theory of magnetic circuits. Such mathematical models are based on a simplified representation of the magnetic system and the magnetic field in the form of a magnetic circuit with corresponding magnetic conductivities. However, unlike traditional rotary type electric machines, electric generators of reciprocating motion have a number of features, the omission of which in mathematical modeling causes the increase of the cost of their creation (due to the duration of the design and experimental refinement of the generators). Therefore, at the initial stages of electromagnetic calculation and solving optimization problems, it is necessary to use adequate mathematical models to improve the accuracy of calculations of the parameters of these generators. For this purpose, a mathematical model based on field theory can be used; however, its main drawback is the complexity of its application for solving optimization problems. In this regard, to improve the accuracy of calculations of the parameters of electric generators of reciprocating motion with permanent magnets, it is proposed to use refining coefficients (coefficients of scattering and buckling of the magnetic flux) in mathematical models based on the theory of magnetic circuits. The authors have developed refined electromagnetic models of electric generators of reciprocating motion with permanent magnets, which make it possible to obtain the main parameters of generators at the initial stages of electromagnetic calculation and when solving optimization problems with acceptable accuracy. A distinctive feature of the refined electromagnetic models of generators is the consideration of the scattering and buckling coefficients of the magnetic flux in the magnetic system that change during the simulation.

The experimental study of the heat flow intensity of a single-row horizontal air-cooled tubular bundle of heat exchanger with spiral aluminum rolling fins at low Reynolds numbers (Re < 2000) is performed. The geometrical dimensions of the bimetallic finned tubes of the bundle, the following: the outer diameter of the fins d = 56.0 mm; the diameter of the tube at the base d0 = 26.8 mm; fin height h = 14.6 mm; pitch of fins s = 2.5 mm; the average fin thickness Δ = 0.5 mm; the coefficient of finned tubes φ = 19.3; heat transfer length l = 300 mm. The outer diameter of the load-bearing steel tube dн = 25 mm; wall thickness d = 2 mm. The research was carried out by the method of full thermal modeling at a specially designed experimental stand with electric heating of tubes and an exhaust shaft installed above the bundle. The air flow rate through the bundle was regulated by changing the height and cross-sectional area of the exhaust shaft. Calibration experiments were carried out and confirmed the reliability of the data obtained. Then the fins were sanded so to form new types of tubes, which were arranged in a single-row six-tube bundle with a constant relative cross-step σ1 = S1/d = 1.14 = const, and the thermal studies were repeated. As a result, a generalized criterion equation for heat transfer of a finned horizontal single-row bundle at small Reynolds numbers for various heights of the tube finning h = 0-14.6 mm was obtained. The effective height of the tube finning (h = 8 mm) for a single-row horizontal bundle was determined by dimensional and metal-intensive criteria.

Thermal power plants remain one of the main sources of environmental pollution. The deterioration of the quality of traditional carbon-containing energy resources leads to the need to develop technologies for co-combustion of biofuel and coal at small and large power plants. The paper proposes the concept of using solid waste from tire recycling by adding to the composition of the mixed fuel “coal – wood waste” as a substitute for coal slag, which is formed during the utilization of worn-out tires by pyrolysis. The aim of the work was to determine the possibility of increasing the calorific value of wood pellets by co-firing with pyrolysis slag instead of coal without increasing the burden on the environment. At the same time, the following tasks have been set: to determine the lowest combustion heat of mixed fuels and assess its change when replacing coal with slag; to determine moisture content, total sulfur content, volatile matter yield, ash content of mixed fuels according to standard methods; to assess the change in these parameters when replacing coal with slag at the same component ratios; to determine the optimal ratios of components in mixed fuels, which will not increase the burden on the environment when replacing coal with pyrolysis slag. It has been determined that replacing coal with slag results in an increase in calorific value by 37–45 %, a decrease in ash content by 37–42 %, and an increase in the yield of volatile substances. At the same time, the sulfur content increases by 5.6–18 %. The use of traditional cleaning equipment is recommended in order to reduce the emission of sulfur dioxide. The research results make it possible to substantiate the possibility of replacing coal with slag in mixed fuels at certain ratios of components. A new direction of using solid products from recycling of rubber products, i.e. worn-out tires, has been proposed by the pyrolysis method in mixed fuels “slag-wood pellets” for small and medium-sized power plants.

The authors showed the necessity to develop a rear-wheel drive hybrid mobile agricultural vehicle with electric drive and power plant. (Research purpose) To develop and study a new kinematic scheme of a mobile vehicle based on a self-propelled tractor T-16 chassis, which provides increased reliability, comfortable working conditions for the operator, a significant improvement in the environmental situation, and better economic efficiency. (Materials and methods) The authors listed the advantages of the new hybrid vehicle kinematic scheme. They gave the comparative technical characteristics of a diesel engine and an asynchronous electric motor. They developed a new methodology for calculating gas turbine engine technical parameters and described the production process of an electric drive with a capacity of 11 kilowatts to drive the driving wheels. The authors gave a thermal design of the compressor parameters, turbine. They calculated the excess air ratio. According to the parameters obtained, a K27-145 turbocharger was chosen, which simultaneously served as a turbine and a compressor of a gas turbine engine. A kinematic diagram was created with a gas turbine electric generator, storage batteries, an asynchronous frequency-controlled motor and a mechanical gearbox. (Results and discussion) The authors proposed to use a mobile vehicle as a mobile power plant: an output socket with a voltage of 220-230 volts operated from an inverter connected to batteries; the second socket – with a three-phase voltage of 400 volts – from the generator of the power gas turbine plant. (Conclusions) It was proved that the proposed hybrid mobile vehicle design on a battery and a gas turbine was capable of operating throughout the entire working day, and to provide 16 horsepower of a diesel engine, it was enough to install an asynchronous electric motor with a capacity of 7.5 kilowatts. The authors calculated the compressor performance of the gas turbine engine, which was 0.178 kilograms per second. The geometric parameters of the combustion chamber and the technical characteristics of the turbocharger were determined.

The efficiency of an enterprise’s power supply system depends on the quality of electricity and the losses of the latter in electrical networks; both being largely determined by the modes of voltage control and reactive power compensation. In practice, the problems of voltage control and reactive power compensation in power supply systems of industrial enterprises, including electric networks with a voltage of up to 1 kV, as well as 6, 10 kV and higher, are often solved separately. It triggers an irrational use of existing voltage control devices, underutilization of the installed capacity of compensating devices, and affects the voltage control in the electrical networks of the power supply organization. Since voltage management and compensation modes of reactive power are inseparable, they can be correctly determined only with the use of an integrated approach based on technical and economic criteria and taking into account technical requirements and local conditions. This article analyzes the mutual influence of voltage control and reactive power compensation modes in the electrical networks of industrial enterprises from the point of view of ensuring the quality of electricity and minimizing load power losses. The method and results of calculations (on the example of a specific industrial facility) for determining voltage deviations and losses in the electrical network as well as for selecting parameters for voltage control and reactive power compensation are presented. Due to the close relationship of these modes that affect all voltage levels, the effectiveness of measures cannot be ensured without the use of multifunctional devices for controlling the equipment of transformer substations.

The reducing in the pressure characteristic of the submersible pump during operation occurs as a result of the combined action of a number of reasons. Pumping equipment wears out due to waterjet destruction of flow channels. The characteristics of submersible pumps are captured at the factory on special stands. At large group groundwater intakes, wells are equipped with an automated control system that allows testing the pump at the workplace and promptly making a decision on its replacement if the pressure characteristic is unacceptably reduced. The actual pressure characteristic of the pump H н = f (Q) can be plotted directly in the well with a sufficient degree of accuracy. To determine the degree of wear of the pump, its pressure characteristics are compared before installation and at the time of taking readings. The article describes a well strapping scheme for measuring the specific flow rate and pressure characteristics of a submersible pump. The purpose of the study is to derive a dependency for constructing the flow-pressure characteristics of a submersible pump at its workplace and to develop a method for accounting for its wear during operation, which allows predicting a decrease in well productivity over time. An expression is proposed to describe the characteristics of the pump at any time, calculated from its installation in the well. The analysis of the reducing in the pressure characteristics of pumps produced by various manufacturers in the wells of the existing water intake of underground water is presented. It is confirmed that the intensity of the pressure reduction depends on the duration of the pump operation in a given well, the material of the pump impellers and the sand content in the pumped water.

A schematic and structural solution of regenerative-utilization heat use in centralized heat supply systems was previously proposed in order to increase the efficiency of operation of heating networks located in non-passable channels. The impossibility of creating a full-scale experimental setup covering the required range of factors and the area of their change, the complexity of a passive experiment on existing heating mains led to the need to develop a virtual model based on the ANSYS sofware package. A six-factor experiment has been carried out on this virtual model. Regression equations have been obtained to determine the pressure required to provide air purging of the channel, as well as heat exchange with pipelines of direct and return network water located in the channel, and heat exchange with soil around the channel. In addition, a regression relationship has been derived to find the integral heat flux from the listed washed surfaces to the air flow. The transition from dimensionless to natural factors has been made in the paper. The most significant factors are identified with the help of Pareto cards. The obtained dependencies have been verified in Part 1 of the paper. The adequacy of the obtained regression equations has been determined using standard statistical estimation methods based on the calculated values of the Fisher’s, Student’s and other criteria. The response surfaces are presented and analyzed using two dimensional sections for a number of factor values at fixed values of one and a change in two most characteristic, physically significant for a given response function. They have been validated on the basis of the analysis of regression dependencies. The obtained regression equations cover almost the entire range of possible diameters of heating mains, which makes it possible to use them in the development of energy-saving projects.

Introduction. During the COVID-19 pandemic variety of digital tools and technologies were demonstrated owing to the global digitalization of education and the total transition to online learning. The purpose of present research is to determine factors of digitalization of education and their effect on transformation of social values among high school students in conditions of the COVID-19. The results of research on social values of students were considered using comparative analysis. It was revealed that the paradigm of values among young people changed from an individual-personal one at the beginning of the XXI century to the social oriented paradigm - tolerance, openness, public recognition through social networks, self-development and contribution to the community. Materials and Methods. The analysis of pedagogical experience in the field of digitalization of education allowed to formulate the main factors of global digitalization of education and to highlight positive and negative aspects of online learning. According to M. Rokich's method, an empirical study of instrumental values transformations was carried out among 137 students of Ural Federal University in the conditions of full-time online learning. A questionnaire method was implemented to determine students' attitude to online learning during COVID-19 pandemic and possibility for further development of this form of learning. Results. It was revealed that only 13.7% of respondents did not notice any decrease in the quality of learning and did not experience discomfort in obtaining knowledge in online form. According to the students' opinion the values that are subjected to transformation are the following: efficiency, self-control, responsibility, honesty. It can be concluded that the era of network personality and new scientific knowledge in pedagogy has begun. Online learning is a fait accompli which requires scientific substantiation of a new didactics and social values system development among students in a digital education environment. Discussion and Conclusion. Achieved results contribute to ecological system of new digital services that change life and educational activities of a human, as well as transform his personality and values system. Thus, for the purpose of health and emotional intelligence preservation in students the continuation of interdisciplinary study of various aspects of education digitalization is required. © Rezer T. M., 2021. Present work is supported by grant of the Institute of Public Administration and Entrepreneurship of Ural Federal University named after the first President of Russia B. N. Yeltsin. This research has is funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant No. АР08856570).

The methods used in the microprocessor protection of electrical equipment for forming orthogonal components of input currents ensure their reliable isolation after changing the mode followed by one or more periods of the fundamental frequency. This is due to the inertia of the functional elements, in particular, digital frequency filters, as well as the saturation of the steel magnetic cores of current transformers. To increase the speed of the selection of orthogonal components of the input currents, it is proposed to form them as equivalent ones in terms of the cosine and sine components obtained using digital Fourier filters by multiplying by the resulting coefficient. The method that has been developed for determining the specified coefficient provides compensation for the delay caused by the inertia of digital filters, as well as the saturation of the steel of magnetic cores of current transformers. The proposed method of forming orthogonal components is highly effective in the modes of strong saturation of the magnetic core with a complex input action in the presence of an aperiodic component with a large damping time constant. The evaluation of the efficiency of the proposed method was performed using a complex digital model implemented in the dynamic modeling environment MatLab-Simulink. As a result of the performed studies, it was found that in the absence of saturation of the magnetic core of current transformers, as well as in the presence of a small and medium degree of saturation, the proposed method for forming equivalent orthogonal components of input currents has dynamic properties close to the ones of those that had been previously proposed. With a strong saturation of the magnetic core of current transformers, the speed of obtaining reliable values of these components is increased by 1.5–2 times.

The mixed problem for the telegraph equation well-known in electrical engineering and electronics, provided that the line is free from distortions, is reduced to a similar problem for one-dimensional inhomogeneous wave equation. An effective way to solve this problem is based on the use of special functions – polylogarithms, which are complex power series with power coefficients, converging in the unit circle. The exact solution of the problem is expressed in integral form in terms of the imaginary part of the first-order polylogarithm on the unit circle, and the approximate one – in the form of a finite sum in terms of the real part of the dilogarithm and the imaginary part of the third-order polylogarithm. All the indicated parts of the polylogarithms are periodic functions that have polynomial expressions of the corresponding degrees on an interval of length in the period, which makes it possible to obtain a solution to the problem in elementary functions. In the paper, we study a mixed problem for the telegrapher’s equation which is well-known in applications. This problem of linear substitution of the desired function witha time-exponential coefficient is reduced to a similar problem for the Klein – Gordon equation. The solution of the latter can be found by dividing the variables in the form of a series of trigonometric functions of a line point with time-dependent coefficients. Such a solution is of little use for practical application, since it requires the calculation of a large number of coefficients-integrals and it is difficult to estimate the error of calculations. In the present paper, we propose another way to solve this problem, based on the use of special He-functions, which are complex power series of a certain type that converge in the unit circle. The exact solution of the problem is presented in integral form in terms of second-order He-functions on the unit circle. The approximate solution is expressed in the final form in terms of third-order He-functions. The paper also proposes a simple and effective estimate of the error of the approximate solution of the problem. It is linear in relation to the line splitting step with a time-exponential coefficient. An example of solving the problem for the Klein – Gordon equation in the way that has been developed is given, and the graphs of exact and approximate solutions are constructed.

A method is proposed for the mechanical calculation of flexible wires of substation in the presence of one tap to an electrical apparatus located in the middle of the span, taking into account its real location. The technique takes into account the presence of tension insulators strings, different heights of the suspension of wires. The loads on the conductor and tap depend on the climatic regime and take into account wind and icy conditions, as well as temperature changes. The transition to another climatic regime is performed by solving the equation of state, taking into account the coefficients of the horizontal and vertical load of the given and initial regimes. Formulas are given for calculating load factors that take into account weight, wind and ice cover loads on wires and insulator strings, as well as the slope of the span. They are calculated for each climatic mode based on the actual location of the tap to the electrical apparatus and the forces from it to the busbar. It is shown that the calculation results are in good agreement with the proposed method and the computer program. Formulas are given for calculating the sag and horizontal deviations of the wires when the tap is located in the middle of the span. A method is proposed for calculating the components of the forces on the busbar from the tap, taking into account its real location in substation. Formulas for calculating these components are given for different variants of the tap orientation. Knowledge of the values of the components of concentrated forces from the tap allows to increase the accuracy of calculating the sag and tension of the substation wires. Formulas are given for calculating the coefficients of increasing the sag, taking into account the components of the forces from the tap.

Preference is given to cable lines with cross-linked polyethylene insulation in electrical networks with a nominal voltage of 10 kV during reconstruction of existing and construction of new industrial enterprises. The standard service life of such cables is at least 30 years (subject to the conditions of storage, transportation, installation and operation), and the actual one is determined by the technical condition of the cable. The service life of a cable line depends on the state of its insulation, the aging of which occurs under the influence of several factors. Conventionally, all factors influencing one or another degree on the cable insulation resource can be divided into thermal, electromagnetic, climatic, mechanical and operational. The most significant reason for the insulation aging is high temperature, which accelerates the reaction of thermo-oxidative destruction, during which high-molecular polymer compounds decompose. In fact, cables are operated at temperatures below the long-term permissible values, and, therefore, the aging of the insulation is slower, and the actual service life will be longer than the standard. At present, condition of the insulation is monitored with the use of high voltage tests related to destructive testing methods. When designing and operating cable lines, it is necessary to estimate the duration of the actual service life under various operating conditions. In theory, there are several expressions for calculating the service life of a cable line when exposed to temperature, humidity, electric field and aggressive environments, but all of them are not applicable in practice due to the presence of a large number of coefficients whose values are unknown. The paper presents an analytical expression obtained for determining the service life of power electric cables, taking into account the aging of the insulation under the influence of temperature and electric field.

The paper presents a thermodynamic analysis of secondary overheating in turbo-expander plants on low-boiling working fluids. The possibility of optimizing the parameters of the working fluid in a secondary stem superheater has been studied. The research was carried out for two typical turbo-expander cycles: with a heat exchanger at the outlet of the turbo-expander, intended for cooling an overheated low-boiling working fluid, and without a heat exchanger. Cycles inT–scoordinates were constructed for the studied schemes. The influence of pressure and temperature in the intermediate superheater on the exergetic efficiency of the turbo-expander unit was studied. Thus, the dependences of the exergetic efficiency and losses on the elements of the turbo-expander cycle are obtained when the temperature of the working fluid changes and pressure of the working fluid not changes in the intermediate superheater, and when the pressure changes and the temperature does not change. As a low-boiling working fluid, the ozone-safe freon R236EA is considered, which has a “dry” saturation line characteristic, zero ozone layer destruction potential, and a global warming potential equal to 1370. It has been determined that increasing the parameters of the low-boiling working fluid in front of the low-pressure turbo expander (regardless of the scheme of the turbo expander cycle) does not always cause an increase in the exergetic efficiency. Thus, overheating of the working fluid at a pressure exceeding the critical pressure causes a positive exergetic effect, but for each temperature there is an optimal pressure at which the efficiency will be maximum. At a pressure below the critical pressure, overheating leads to a decrease in the exergetic efficiency, and the maximum exergetic effect is achieved in the absence of a secondary steam superheater. All other things being equal, a turbo-expander cycle with a heat exchanger is more efficient than without it over the entire temperature range and pressure of the low-boiling working fluid under study.

The results of the research were obtained in 2019-2020 on sod-podzolic middle-loam soil in the conditions of EuroNorth-East of the Russian Federation. There were studied 18 variants of increasing doses of mineral fertilizers in the range from 30 to 150 kg of active ingredient per hectare. Under the conditions of 2019 growing season, nitrogen fertilizers influenced the value of yield of Novichok barley variety to a greater extent (Y = 0.67 - 0. 11x2 + 1.33x, R2 = 0.92), in 2020 - phosphorus fertilizers (Y = 1.48 - 0.02x2 + 0.48x, R2 = 0.99). On average, over 2 years of research, the yield in the control variant without the use of fertilizers was 0.87 t/ha. Yield increase of barley grains because of enlarged fertilizer doses ranged from 1.38 to 3.90 t/ha. The payback of 1 kg of active ingredient of fertilizers with increase of barley yield decreased due to enlarged doses: from 15.3 (N30P30K30) to 8.3 kg (N150P150K150). On average for two years of the research the increasing doses and ratios of mineral fertilizers had no significant effect on technological properties of spring barley seeds. The content of crude protein in grain grew with increase in fertilizer doses (r = 0.55). To obtain grain of the 2nd class of quality it is necessary to apply not less than 90 kg of active ingredient/hectare of ammonium nitrate. According to the content of crude cellulose, the 1st class of grain quality has been obtained, and this indicator did not depend on the application of fertilizers. High profitability of cultivation of the Novichok spring barley variety (from 54.2 to 59.1 %) has been recorded by application of mineral fertilizers in doses N60P60N120, N60P60K60 and N120P120K120.

Due to the fact that most of the large oil fields in Russia, characterized by high production costs, are at the final stage of development; the issue of cost optimization has become increasingly important in recent years. The main cost items at oil and gas enterprises are design and construction (reconstruction) of oil field facilities. Analysis of currently used methods for ranking oil and gas projects has shown that all of them are inherently subjective, since they are based on expert opinion. The authors have developed a methodological tools for evaluating the effectiveness of capital construction projects of oil field facilities (for example, construction work on the site for inventory receiving bridges and lifting units), which allows to eliminate the influence of expert opinion as much as possible and, consequently, significantly improve the quality and validity of management decisions. The choice of the optimal project is based on a two – level assessment (stage 1– technical assessment, stage 2 – economic assessment). At each stage, an integral indicator is determined by calculation based on the results of objective data analysis and using the developed algorithms. Thus, it is possible to judge the effectiveness of any project without being based on a subjective approach in the assessment with the help of expert opinion.

The article examines the possibility of increasing the efficiency of the turbo-expander cycles on low-boiling working fluids using those methods that are used for steam turbines, viz. increasing the parameters of the working fluid before the turbo-expander and using secondary overheating. Thus, four schemes of the turbo-expander cycle are considered: the one without overheating of the low-boiling working fluid, the one with single overheating of low-boiling fluid, the one with double overheating and the one with double overheating at supercritical parameters. All the studied cycles were considered with a heat exchanger at the outlet of the turbo expander, designed to heat the condensate of a low-boiling working fluid formed in the condenser of the turbo expander unit. Cycles inP–hcoordinates were built for the studied schemes. The method of thermodynamic analysis of the studied cycles based on the exergetic efficiency has been developed. The results of the research are presented in the form of Grassman-Shargut diagrams, which show exergy losses in the elements of the studied cycles on a scale, and also show the positive effect of the operation of the turbo-expander cycle in the form of electrical power. The analysis of the obtained results showed that the main losses that have a significant impact on the exergy efficiency are the losses of exergy in the recovery boiler. The increase of parameters of low-boiling working body, and the use of intermediate superheating reduce losses in the waste heat boiler and, consequently, increases exergetic efficiency of turbo-expander cycle. The turbo-expander cycle with double overheating at supercritical parameters of the low-boiling fluid is of the largest exergetic efficiency out of the schemes that have been examined.

In recent years, electric energy storage systems are considered as a key element in the technological development of vehicles, renewable energy. This article provides a brief description of modeling methods, some new approaches and the results of modeling batteries in parallelto-serial assemblies that can be used to design storage units for local power systems. A battery is a very complex physicochemical, electrochemical and electrotechnical object, the modeling of which can be carried out at various depth levels and by various methods. Battery modeling options are being considered. Presentation of the battery in the form of equivalent circuits is in good agreement with the general approach of graphical representation of electrical systems in such packages as MatLab-Simulink, Electronics Workbench and the like. Two directions of battery modeling can be distinguished, viz. modeling current battery parameters during a charge-discharge cycle and modeling the parameters of the functional state of the batteries over a long period of operation. These directions consider different characteristic time periods (hours and days in the first case and hundreds of days in the second one), differ in the parameters taken into account and are relatively independent. The latest versions of MatLab-Simulink have a built-in model with degradation of battery parameters. The built-in battery model is quite complex and when simulating the operation of more than one battery, the time period of counting increases significantly. When modeling assemblies from a large number of batteries connected in parallel-to-series, the time in the program practically stops, which indicates the impossibility of modeling large assemblies. Nevertheless, the Electronics Workbench electronics lab has shown its performance. When using the similarity criterion, Electronics Workbench has the potential to complicate the circuits, which makes it possible to analyze parallel-serial battery assemblies.

The article present the analysis of the operation of the mini-energy complex (MEC) based on alternative energy sources. An asynchronous generator (AG) was taken as energy source. The IEC operates independently with standard power parameters without the use of a frequency converter. To operate independently, AG needs a source of reactive excitation current. Based on the calculations carried out and the results obtained with the use of the experimental facility,the operating conditions of the MEC with standard parameters of electricity under varying load have been analyzed. A characteristic feature of the autonomous MEC is the commensurate capacity of the generating device and consumers. Therefore, any power consumer on/off leads both to significant changes of local electric system parameters and affects the operation of the generator itself. In this article, the main attention is paid to the influence of three-phase motor load on stable AG operation. When the MEC operates independently, reliable self-excitation of the asynchronous generator and the start-up of consumers whose power is commensurate with the generating unit must be ensured. It is also necessary to ensure the maintenance of voltage stability, the possibility of automatic operation of the generating unit, and the preservation of its integrity in emergency modes. Thus, for stable MEC-based AG operation the nature of the load should be taken take into account, the parameters of the of the local grid should be known as well as the exact availability of consumers and their characteristics, and also equivalent circuit parameters of asynchronous motors. In addition, it is necessary to accurately calculate the capacity when changing the parameters of the electrical system, so as not to lose the self-excitation of the asynchronous generator, which is equivalent to disconnecting the entire load of the generator and causes a sharp increase in speed. To solve these problems, it is necessary to create a high-speed MEC control system.

The article presents an analysis of the state of development of solar energy in Europe and the Republic of Belarus for 2020. An algorithm for increasing the efficiency factor of solar power plants by localizing the solar trajectory depending on the latitude and longitude of the area has been proposed. In particular, taking into account the angle of the Sun position above the horizon and the azimuth angle of the Sun, the increase in the efficiency factor of solar power plants for the Republic of Belarus is calculated. Based on this algorithm, a program has been written that makes it possible to draw a diagram of the solar trajectory. An analysis has been made of the degree of localization of solar energy for solstice days in 6 oblast (regional) centers of the Republic of Belarus; it is found that the highest intensity of solar radiation is observed in Brest and Gomel, the average in Grodno, Minsk and Mogilev, while the lowest one – in the city of Vitebsk. A comparative analysis of the solar trajectory of the city of Berlin (Germany) with the city of Gomel and the city of Brest is carried out. Recommendations have been developed for the effective operation of solar power plants in the oblast (regional) cities of the Republic of Belarus during the year in an autonomous and combined mode of operation. The obtained numerical calculations of the solar trajectory make it possible to optimize the orientation of solar panels for permanently installed panels and for automated solar tracking systems, as well as to select the optimal configuration of the power plant equipment for any geographic area.

The article features an experimental study of thermally thin biomass samples (beech wood particles 17×8×6 mm) pyrolysis in a laboratory scale batch reactor. The reactor was a cylindrical steel body with internal diameter of 200 mm and height of 500 mm. The temperature of a lateral surface of the cylinder during the experiment was being kept constant (550 °C) due to electrical heating. The initial loading of the apparatus was about 4 kg with moisture content of about 14 % by weight. During the experiment, the temperature values of the material being pyrolyzed were recorded at two points of the radial coordinate, viz. at the wall of the apparatus and on its axis. A one-dimensional numerical model of the nonstationary process of biomass conversion (heat and mass transfer in combination with the Avrami – Erofeev reaction model) has been proposed and verified. The reactor is represented as a set of a countable number of cylindrical layers, considered as cells (representative meso-volumes) with an ideal mixing of the properties inside. The cylindrical surfaces that form cells are considered to be isothermal. The size of the cells is chosen to be sufficiently large in comparison with the individual particles of the layer, which makes it possible to consider the temperature field inside the cell volume as monotonic. The evolution of the temperature distribution over the radius of a cylindrical reactor is determined on the basis of a difference approximation of the process of non-stationary thermal conductivity. The calculated forecasts and experimental data showed a good agreement, which indicates the adequacy of the developed mathematical model of pyrolysis and makes it possible to recommend it for engineering calculations of biomass pyrolysis. This model can also be useful in improving the understanding of the basic physical and chemical processes occurring in the conditions of biomass pyrolysis.

Purpose: this article analyzes India’s innovation development model. In this regard, the author aims to examine the current state of India's innovation policy as well as its features as one of the tools for solving the socio-economic problems of the state.Methods: the author applies general scientific methods of logical analysis, comparison and generalization, as well as quantitative methods (graphical and tabular methods, and descriptive statistics). In addition, the article embraces a systematic approach that contributes to a holistic consideration of the research subject.Results: the article provides an overview of the fundamental documents and projects of the state's innovation policy, studies India’s positions in world innovation ratings as well as notes the unique features of the Indian model of innovative development associated with the government strategy adjusted to the socio-economic, cultural and civilizational features of this country.Conclusions and Relevance: the article addresses the distinguishing characteristics which have eventually become disadvantages of the existing system and touches upon the reasons that hinder the development of innovations and prevent the country from achieving tangible results in this domain. The author concludes that without systematic government support, appropriate staffing, and functioning triple helix model involving academia, industry, and government, the country's innovative development will be limited, and India will fail to address the ever-widening gap between grassroots and high-tech innovation sectors will continue to grow. Still, Russia may learn a lot from the Indian experience as it also aims at solving its “grand challenges”, including those of social and economic nature, by the means of innovations.

Borehole water intakes of underground water are widely used for water supply of agricultural towns, urban settlements, small and large cities and megacities. The number of consumers in these localities determines the number of water intakes, the number of wells, their productivity, location and connection to the prefabricated water conduits. Due to the increase in the use of underground water, the existing water intakes are being reconstructed and expanded. These works are accompanied by grouting of failed wells, their re-drilling, drilling of additional wells, re-laying of old and laying of new prefabricated water conduits. All this causes the complexity of the configuration of prefabricated water conduits due to the construction of jumpers and rings, the emergence of new wells with connection lines. Under the new conditions, in order to properly develop water intake operating modes which meet the minimum energy consumption for lifting and delivering a required volume of water to the collection-and-control tanks, to accurately choose the appropriate water lifting equipment in wells, to develop measures for intensifying water intake alongside with a forecast of their efficiency and to optimize the operation of the water intake, it is necessary to create its mathematical model that allows performing complex calculations. Water intakes with ramified prefabricated water conduits, as well as with an area scheme of the location of wells and a ring scheme of the connection of prefabricated water conduits are the most difficult object for mathematical modeling. The methods of calculating such water intakes are not sufficiently reflected in the literature, and there are no specific examples of calculation. The present article aims to clarify the methodology for calculating borehole water intakes with ramified prefabricated water conduits and with a ring scheme of their connection.

The linear wind load on the wires and cables acting perpendicular to the wire depends on the angle between the direction of the wind and the axis of the overhead line. In the methodology of mechanical calculation of wires and cables, it is recommended to take the wind directed at an angle of 90° to the axis of span and it is not specified which side the wind blows from. For spans of air, this is not so much significant as for switchgear spans, where the deviations of the wires depend on the direction of action of the taps to the electrical apparatus. The article discusses various options for the location of taps and their effect on the wire, as well as changing the direction of the wind. An algorithm for calculating the horizontal deviation of a flexible wire and its increase coefficients in the presence of horizontal concentrated loads due to the action of windon spacers, barriers, taps to electrical apparatuses and other structural elements of substations and overhead lines is given. In the absence of wind, horizontal concentrated loads and deviations occur when an arrangement of the taps is non-keel. The formulas for calculating the horizontal component of the load coefficient to solve the equation of state in the presence of horizontal concentrated forces acting in any direction have been derived. The results of the mechanical calculation are obtained for the cases of one and two horizontal concentrated forces, differently oriented with respect to the distributed wind load. In design practice it is recommended to take the wind flow in the direction of the action of horizontal concentrated forces, since in this case the greatest horizontal deviations and load factors are obtained. The reduction in the coefficients of the horizontal load occurs when the current lead is unloaded because of the opposite directions of the wind and horizontal concentrated forces. In the absence of wind, it is proposed to use the formulas for calculating horizontal deviations and load after finding the product of the coefficient of increase in horizontal deviations and the horizontal component of the coefficient of load per linear load.

For sowing small seeds of vegetables, in particular onions, special seeders are used. They are not produced in the Republic of Uzbekistan, while many diff erent pneumatic seeders are produced abroad. The authors note that foreign samples are complex in design, not adapted to local soil and climatic conditions, cannot provide even seed placement on ridges, and the cost of the seeders themselves and service are very high.(Research purpose) To develop a vegetable seeder in relation to the soil and climatic conditions of Uzbekistan, to determine the seeding rate of onion seeds depending on the length of the active part of the seed reel, to evaluate the formation quality of sowing ridges and irrigation furrows.(Materials and methods) The authors determined the sowing rate by turning the seeder drive wheel at a given length of the active part of the sowing reel and collecting the sown seeds in cups with further weighing. The quality of sowing ridges and irrigation furrows formation was evaluated by the method of profi ling the fi eld before and after the seeder’s pass.(Results and discussion) The authors developed a vegetable seeder that performed three operations in one pass: cutting irrigation furrows, forming sowing ridges of a trapezoidal shape and sowing onion seeds and other small-seeded vegetable crops in a three-row tape method in each tape. They found that the dependence of the seeding rate on the length of the active part of the reel had a slightly fragile parabolic shape, and the required seeding rates – 24-48 pieces per linear meter (3.9-7.8 kilograms per hectare) – were provided with the length of the sowing reel 3.3- 6.2 millimeters. It was proved that the seeder provided a high-quality formation of sowing ridges and irrigation furrows: the row spacing was 68.8 centimeters (installation spacing – 70 centimeters), the top ridge width was 42.5 centimeters (the predetermined one was 40 centimeters), the depth of irrigation furrows was on average 9.6 centimeters.(Conclusions) A vegetable seeder was developed for sowing small-seeded vegetable crops with the simultaneous formation of sowing ridges and cutting irrigation furrows, which ensured high-quality performance of all operations and observance of onion seeds.

Introduction. The present article considers the problem of readiness of young teachers to teach children with special educational needs in countries where the introduction of inclusive education began only in the last decade. The authors describe the key concepts of the theory of formation of professional skills and competences of teachers for working in inclusive education, based on which the results of research conducted in theCzechRepublic,Poland andRussia.The aim of this article is to compare the experience of young teachers in teaching children with special educational needs in relation to their skills and competences needed to perform this task.Methodology and research methods. Questionnaires and interviews were used to collect quantitative and qualitative data, which were eventually processed using basic statistics (quantitative survey) and the open-coding method (qualitative content).Results. The results of the study indicate both strong and weak aspects of the skills of young teachers in teaching students with special educational needs. In particular, a qualitative analysis of teachers’ responses revealed some interesting ideas that can be used in the search for improvements in teacher training, as well as in the support provided to teachers working with children with special educational needs directly in the school environment at the beginning of their professional careers. In general, it can be stated that young teachers in all three countries do not feel sufficiently qualified in terms of training to work with these children and are in need of expert support.Scientific novelty. The results of the current research allow for the determination of some priorities in teacher training for the modern development of inclusive education in the countries examined.Practical significance. The presented materials of the research can become the basis for developing a system of expert support for young teachers in the implementation of inclusive education, as well as new programs for preparing future teachers to work with pupils with special educational needs.

A significant rise in the mass production of products that contain nanoparticles is of growing concern due to the detection of their toxic effects on living organisms. The standard method for analyzing the toxicity of substances, including nanomaterials, is toxicological testing, which requires the substantial consumption of time and material resources. An alternative approach is to develop models that predict the effect of nanomaterials on biological systems. In both cases, for the detection of nanoparticles an effective electronic complex consisting of a sensor with high sensitivity and a data reception/processing/transmission system is necessary. In recent times, fundamental and applied research activities aimed at the application of heterostructure field-effect transistors – high electron mobility transistors–as a base for such sensors have been undertaken. The purpose of this work is to develop a technique for modeling a sensor for toxic nanoparticles based on the heterostructure field-effect transistor. The object of the research is a gallium nitride high electron mobility transistor device structure. The subject of the research is the electrical characteristics of the transistor obtained in static mode. The calculation results show that the dependence between the concentration of the toxic nanoparticles in the test medium and the polarization charge surface density could serve as a base for modeling the sensor for toxic nanoparticles based on the heterostructure field-effect transistor. The primary advantage of the proposed technique is the use of the scaling parameter intended directly for calibrating the polarization charge density in accordance with the two-dimensional electron gas concentration. The obtained results can be utilized by the electronics industry of the Republic of Belarus for developing the hardware components of gallium nitride high-frequency electronics.

The article discusses the formation of complex tasks of information support processes of development, manufacturing and subsequent mass long-term operation of new and advanced aircraft, aimed at further development of innovative approaches to integrated cross-industry system (platform) after-sales support of technical and flight-technical operation of civil aircraft. The article reveals the content of the main tasks focused on ensuring and managing flight safety in civil aviation of Russia and interrelated with the recommendations and legislative requirements of Annex 19 to the ICAO Convention and the Safety Management Manual. The most important factor in this case is to take into account the most complex requirements for the flight safety management system associated with maintaining the airworthiness of aircraft as a mode of transport of particular risk of use. The analysis was carried out and the General Scheme of the Multifunctional Integrated Platform was developed within the framework of the Information and Analytical Support System for the technical operation of aircraft components in relation to the scientific and production enterprise "Aerosila". The developed integrated platform realized in this air enterprise and providing information support on the allocated main functional modules is presented: the module "Safety Management System"; the module "Quality System"; the module "Certification" on the allocated objects of certification. As a result, a common information and analytical system was built, taking into account the degree of its implementation in the conditions of “Aerosila” air enterprise.

Improving the operational efficiency (OE) of thermal power plants is one of the most important problems of electric power systems (EPS). According to modern concepts, efficiency is the simultaneous consideration of three properties of objects, viz. economy, reliability and safety. The methodology of their joint assessment assumes that the service life of the main equipment does not exceed the standard value, but this condition is now met by less than half of the production enterprises of a lot of EPS. In order to increase OE, it is necessary, first of all, to learn how to objectively compare the performance of objects both of the same type – in a given time interval, and unique ones – in adjacent intervals. Existing methods for calculating integrated performance indicators do not fully take into account the random nature of technical and economic indicators (TEI). The article presents a new method for comparing the OE of EPS objects, the essence of which is to switch from joint consideration of TEI to analysis of their relative changes in comparison with the factory default value (nominal value). Relative values of indicators characterize the amount of wear or residual life. In this case, for example, the arithmetic mean of the relative values of the TEI determines the average wear of the object. This physical representation enlivens integral indicators, and their comparison and ranking ceases to be science-intensive. It is proposed to take into account also the degree of variation of relative deviations (wear), which is adequate to the object’s misalignment. It manifests itself in a significant change (deterioration) of one or (less often) two relative values of the TEI in the calculated time interval (month) and is characterized by such statistical indicators as the geometric mean and the coefficient of variation of relative deviations. Herewith, if the arithmetic mean value of the object’s wear is restored during major repairs, then the misalignment is eliminated much faster – during current repairs. A necessary condition for the feasibility of using these or those integral indicators is their functional and statistical independence. The results of the studies performed using the simulation method made it possible to establish that the smallest correlation occurs between the integral indicator calculated as the arithmetic mean of random variables and the integral indicator calculated as the coefficient of variation of the same random variables. Comparison of correlation fields clearly confirms these conclusions.

Introduction. When selecting urbanized locations for parks and squares as centers of improvement and comfort of the urban environment, it is necessary to involve not only public authorities, but also activists. The purpose of the study is to build an algorithm for the development of public spaces in large cities, taking into account the schemes of interaction between state, municipal and business entities and activists. Materials and Methods. The study was based on publications by Russian and foreign scientists, regulatory documents on the research problem. The Rostov Region was the research subject, as well as the center of the region, the city of Rostov-on-Don with a population of over one million. The authors have analyzed the results of sociological surveys and rating voting on the development of public spaces in cities. The use of analytical methods and research techniques (analysis, generalization, induction and deduction, systems approach) made it possible to substantiate the authors’ point of view and the algorithm for the development of public spaces in large cities. Results. The scientific knowledge on the issues of harmonizing the interests of the population of large cities, municipal authorities, and business entities has been systematized in terms of improving urban planning, social and environmental strategies for the development of the region, based on information resources of the main indicators of the state of the environment and the investment attractiveness of the Rostov Region. Practical recommendations have been formulated for regional public authorities to ensure effective use of public spaces in large cities in the context urbanization. Discussion and Conclusion. Based on the study, the authors have proposed an algorithm for the development of public spaces in cities, which will combine the efforts of public authorities, business entities and the population in creating a comfortable urban environment in large cities. The materials of the article will be useful for city managers and heads of regions, as well as for specialists involved in the landscaping of public spaces.

The magnetizing current inrush appears in electrical power units equipped with transformers in case of no-load energizing of the power transformers and in a number of other cases. This phenomenon could cause a false triggering of the current protection. To prevent incorrect actions of the current protection during the magnetizing current inrush a protection blocking is carrying out. The blocking principle operation is based on the fact that in a three-phase system in normal mode and in case of symmetrical short circuit the first harmonics contained in the phase currents of electrical installations form a direct sequence and the second ones – the negative sequences. In case of an asymmetric mode, including an asymmetric short circuit, the negative sequence appears, formed by the first harmonics that are part of the phase currents of the specified system. In magnetizing current inrush modes, second harmonics of significant magnitude are present in phase currents, which form the negative sequence. Based on the analysis of the information parameters of the specified sequences currents, identification of the magnetizing current inrush and short-circuit modes is performed with the implementation of the protection blocking if necessary. The study of the current protection blocking functioning was performed using computational experiment by analyzing the calculated changes of blocking parameter compared with the threshold setpoint. The specified researching is done by using the digital model that is implemented in the dynamic modeling environment MatLab-Simulink. As a result of the performed calculations, the principal operability of the proposed current protection blocking was confirmed that provides a fairly reliable identification of the magnetizing current inrush and short-circuits modes, regardless of the degree of saturation of current transformers. It was found that the proposed principle of the current protection blocking has a higher sensitivity in comparison with the classical one based on the estimation of the ratio of the second and first harmonics of the phase currents. In short-circuit modes in an electrical power units the proposed blocking causes a current protection operation delay that can be reduced by digital filters performance improvement.

The paper gives an analysis of perspectives for development of wind power generation, information on the share of wind energy in electricity generation in the world and in Russian Federation is provided as well. Data on gross, technical, economic potential of wind energy of Russia and the Murmansk Region has been presented. When calculating the gross wind energy potential of the region, data from the last 10 years of observations carried out at 37 meteorological stations have been used. The territory of the region has been divided into 6 distinctive zones, based on the wind activity. Gross energy potential has been calculated for each zone: for the heights of 10, 50, 100, and 150 m. Gross wind energy potential of the region at the height of 150 m has thus been estimated at 23,090 billion kWh. The Murmansk Region's 201 MW Kola wind farm, which consists of 57 Siemens Gamesa SG 3.4-132 wind turbines with a unit capacity of 3.465 MW, is to be constructed by 2021 under the direction of Enel Green Power. Wind energy potential and annual power generation of the Kola wind farm have been assessed. The difference between the obtained results and calculations of Enel Group's specialists amounts to less than 15 %. For the cases of relocation of Kola wind farm to different wind zones, the annual power generation of the wind farm has been estimated. It has been determined, that in case of Kola wind farm's relocation to the zone with the highest wind activity its annual electricity generation could be increased up to 1.5 times. A model of the Kola energy system has been developed in NEPLAN software, its validity has been proven. The calculations of the wind farm's operation modes show that voltage levels of the system nodes and powerflows are within the boundaries defined by normative documents. The effectiveness of reactive power regulation of the wind farm has been shown.

The article considers 46 low-boiling working media (LBWM) with zero potential for ozone layer destruction. Out of them, 14 ones are single-component hydrofluorocarbon refrigerants, 28 ones are multi-component mixtures of hydrofluorocarbon refrigerants, and the four ones are native refrigerants. Thermodynamic analysis of working media based on the classical turbo-expander scheme with a heat exchanger designed to cool the superheated LBWM that has left the turbo-expander has been performed. For this scheme, a cycle is constructed in T–s-coordinates. The LBWM was compared using the exergetic coefficient of efficiency (KE). In the course of the study, it was found that for some LBWM, the sequence of location of the exergetic efficiencydependences on temperature at thermodynamically optimal working medium pressures is preserved over the entire temperature range under study (from 100 to 300 оC). In other words,if the working medium has the highest exergetic efficiency coefficient, then this property is inherent in it at any temperature in a given interval. It is proposed to perform the analysis of the LBWM for exergetic efficiency at an arbitrarily selected temperature (250 оC). The study demonstrated that the highest exergetic efficiency of natural refrigerants is R600A (50.25 %), among single component hydrofluorocarbon refrigerants – R245FA (50.00 %), R1233ZD(E) (49.91 %), R236EA (49.59 %), among multi-component mixtures of hydrofluorocarbon refrigerants – R429A (47.92 %), R430A (47.49 %) and R423A (47.47 %). Out of the all examined refrigerants, the following ones have the highest exergetic efficiency of all the considered LBWM: R600A, R245FA, R1233ZD(E), R236EA, R1234ZE(Z), R236FA. They belong to both natural refrigerants (hydrocarbons) and single-component hydrofluorocarbons. It should be noted that each of these working media has its drawbacks: some have a high potential for global warming, others are explosive, and others have a high cost.

Background. The Novo-Uchaly copper-zinc VMS deposit in the Southern Urals (54°10΄54˝N and 59°20΄45˝E) is represented by a steeply dipping lens of Eifelian volcanics (rhyodacites and basalts), which are crumpled into a strongly compressed anticlinal fold. The ore deposit is blind and localised at the convergence of felsic (bottom) and mafic (top) rocks. The deposit is located at depths of 550 m (in the northern part) and 1050 m (in the southern part). The deposit thickness reaches 186 m. The length along the strike and along the dip equals 1250 m and 900 m, respectively. The ore body is intruded by gabbro-diorite and gabbro-diabase dikes. The main ore minerals are pyrite, sphalerite and chalcopyrite, as well as non-metallic minerals, such as quartz, barite and calcite. Unlike most of the Ural VMS deposits, this deposit is the zinc subtype (Zn >> Cu). The ores are predominantly massive and solid sulphide, being banded or brecciated in some parts. The main elements extracted are copper, zinc and sulphur, but gold, silver, cadmium, indium, cobalt, nickel, selenium and tellurium are also obtained.Aim. To clarify the morphology of the ore deposit, to study the ore mineral composition of the upper horizons of its northern part and to determine the underlying reasons for the complex lenticular structure of the sulphide reserve.Materials and methods. In the period 2017—2019, employees of the Institute of Ore Deposits, Petrography, Mineralogy and Biochemistry of the Russian Academy of Sciences (IGEM RAS) together with geologists of the Uchaly Mining and Processing Plant carried out a geological and mineralogical mapping of the deposit in the course of exploration works.Results. The ore contours and mineral composition of the northern part of the ore body were significantly clarified. A series of dikes of variable morphology was identified. A comparison was made of the results with current theories about the structure of the ore deposit. Detailed geological sections were determined and illustrate the complex lenticular structure of the ore deposit complicated by pinch and swell areas. The deposit was formed by processes of dynamic metamorphism.Conclusion. The geological and mineralogical structure of the deposit determined in the study enabled us to propose a schematic reconstruction of the conditions leading to the formation of its folded structure. The findings will help to re-assess the reserves and improve the system of operational exploration and delineation.

Background. Various approaches are currently used to create borehole curvature depending on associated methodological and practical geological problems. Continuous action whipstockes are considered to be the most modern and accurate among these approaches. The efficiency of such devices may decrease under difficult mining and geological conditions.Aim. To increase the efficiency of drilling a curved borehole in hard and very hard rocks by reducing the speed of drilling out an artificial bottom.Materials and methods. We studied the operating principles of various types of continuous action whipstocks. Empirical results were determined by studying the operation of continuous milling whipstocks in difficult rock conditions and by studying the materials used for manufacturing artificial bottom holes. The study included optimization of the efficiency of drilling a well in hard rocks from an artificial bottom hole in a new direction.Results. The main factors decreasing the whipstock efficiency were found to be the mechanism of buildup rate, and the different strength of the rock and artificial bottom-hole. A feature of the work of a milling type whipstocks is that the creation of a deflecting force is carried out due to the constant influence of the axial load, the value of which proportionally affects the speed of drilling. A review of the materials used to create an artificial bottom led to the conclusion that at present there are no curable materials that would have a hardness higher than category 8 for drillability, which means that when trying to drill a new direction of a well in rocks more than 8 grade for drillability, the speed drilling with a continuous action whipstocks will exceed the optimum and reduce the intensity of the buildup rate whipstock.Conclusion. Since the rate of drilling an artificial bottom hole is difficult to regulate using the drilling mode parameters, it is necessary to develop technical solutions that would limit the rate of deepening a new direction of the wellbore.

Thermosyphons and heat pipes offer great opportunities for creating pas sive heat and mass transfer systems. Various design solutions using heat pipes (thermosyphons) in solar energy systems are known. Solar energy is one of the promising energy sources, a step towards reducing dependence on other energy resources. To date, there is already an industrial production of solar collectors based on thermosyphons (heat pipes). In solar collectors, the use of thermosyphons (heat pipes) makes it possible to simplify the assembly of the structure, ensures its high modularity, maintainability and reliability. In the course of research, the authors have developed and justified the design of a solar collector based on thermosyphons fixed on panels that absorb solar rays. In order to analyze the efficiency of the solar collector based on two-phase copper thermosyphons, two models of solar collectors were created, viz. the one with a flat absorbing panel and the one with a cylindrical absorbing panel. The areas of the absorbing surfaces were the same. Both models were studied by the method of thermophysycal experiment. The results of studies of the effectiveness of the above-mentioned solar collectors have been obtained. The efficiency of the solar collector based on a copper two-phase thermosyphon, which is fixed on a cylindrical absorbing panel is 2–5 % more than the efficiency of the solar collector based on a copper two-phase thermosyphon, which is fixed on a flat absorbing panel. The maximum efficiency value obtained at low initial water temperatures for solar collectors with a cylindrical and flat absorbing surface was 60 %.

The paper studied the process of intensification of concentrated fermentation mash with account of the complex amylolytic enzymes, hemicellulase and proteolytic activities. We determined the dependence of ethanol yield, the content of volatile impurities, the content of reducing substances, depending on the different strains of yeast at a seed rate 15 million cells per 1 cm3 wort. To identify the parameters of the fermentation process the wort with an increased solids content, investigated the dynamics of accumulation of volatile impurities by varying the rate and duration of seeding yeast fermentation using 987-O5 race yeast. It revealed that the qualitative composition of impurities in the mash, the resulting wort of high-concentration depends both on the duration of fermentation, and from normal seeding yeast. Thus, depending on the duration of the fermentation process, the acetaldehyde content increases (from 613,17 mg/dm? to 54 h to 1724,6 mg/dm? to 72 hours), the amount of ethyl acetate is reduced (from 409,2 mg/dm? to 54 hours prior to 207 mg/dm? to 72 hours), the methanol content to 54 h at a rate of 15 million yeast seeding cells per 1 cm? of the wort amounted to 0,0043 mg/cm?, whereas by 72 h of fermentation at the same seed rate yeast – 0,0070 mg/dm?, the amount of 1-propanol and 1-butanol was reduced from 903,14 mg/cm? and 6,38 mg/cm? -54 h to 880 mg/cm? and 5,57 mg/cm? - to 72 hours, respectively. The minimum content of isobutanol independent of the duration of fermentation was 900-1100 mg/cm? at a seed rate 15 million yeast cells per 1 cm? wort izoamilola number increases from 1219,08 mg/dm? (54 hr) to 2673,84 mg/dm? (72 h). It revealed that the smallest total amount of impurities obtained by seed rate yeast 15 million cells per 1 cm? wort at the duration of fermentation 54 hours was found that maximum ethanol content in the mash with minimal accumulation therein volatiles corresponds embodiment:. Duration of fermentation - 54 hours at normally the problem of yeast cells – 15,0 million / cm? wort.

In the production of low-alcohol and non-alcoholic beverages, the use of preservatives is allowed, including benzoic acid (BК) and its salts. Standard methods based on high performance liquid chromatography are used to control the content of this preservative. This work presents the results on the determination of benzoic acid in samples of low-alcohol and non-alcoholic products by the spectrophotometric method. Research has been carried out to establish the optimal wavelength when measuring the optical density of benzoic acid solutions. A calibration characteristic has been constructed to determine the mass concentration of benzoic acid, which makes it possible to determine its concentration in the range from 10 mg/dm3 to 500 mg/dm3 of benzoic acid, taking into account dilution. Metrological data have been obtained for constructing a calibration characteristic for the determination of benzoic acid in low-alcohol and non-alcoholic products. It is shown that the results of the determination of this preservative in the indicated products by the spectrophotometric method are comparable with the analogous results obtained using standard methods based on high performance liquid chromatography. The research results became the basis for the developed Methodology for measuring the mass concentration of sorbic and benzoic acids in low-alcohol and non-alcoholic products by the spectrophotometric method. The developed technique allows measuring the mass concentration of benzoic acid in low-alcohol and non-alcoholic products containing only benzoic acid. The spectrophotometric method for determining the mass concentration of BA is a less costly method for determining this preservative in a product than the currently used method of high-performance liquid chromatography, does not require special expensive equipment, additional consumables and specially trained personnel..

This paper deals with the problem of constructing a mathematical model for studying the thermal regime of a test system at the design stage. The test system is presented as a complex chemical-technological system, which includes a large number of elements, components and devices, characterized by a variety of functional and thermal relationships. The block-hierarchical method is used for designing the system under consideration. A thermal block diagram of the system has been developed, which includes six interconnected blocks: a thermostat; coolant; heat exchanger; cubic apparatus, medium in apparatus and environment. A mathematical model has been created to estimate the average temperatures in the system, which allows you to calculate the integral characteristics of heat exchange processes (the values average intake temperatures and the values surface average temperatures, average heat fluxes) taking into account the interaction between all blocks of the system. It was assumed that each element of the system under consideration can have thermal connections, both with the environment and with other elements of the system. It was assumed that the element can dissipate its own power, as well as the power supplied for thermal control of the element, which depends on its temperature. The calculation of the temperature fields of bodies and flows of heat carriers was carried out on the basis of models with concentrated parameters, with the assumption that there are no temperature gradients in all directions. The model is represented by a system of ordinary differential equations. The dependences of temperature on time change for two non-stationary modes of a thermostatic system consisting of a hollow device of cubic shape with a volume 3 m3 filled with gas and equipped with a heat exchanger are shown. The developed mathematical model allows solving the problems of temperature stabilization of the test system.

Modern highly mechanized agricultural production is characterized by the incompatibility of simultaneous matching of the maximum pressure of agricultural mobile equipment movers on the soil and the possibility of increasing the tractors energy saturation when equipping them with existing wheel engines.(Research purpose)To coordinate the maximum pressure on the soil with the permissible norms, weight utilization factors and the level of tractors energy saturation.(Materials and methods)The authors used a calculated method for determining the maximum pressure on the soil using a universal tire characteristic.(Results and discussion)The authors found that when performing spring works on closing moisture and sowing row crops at a maximum pressure of 80 kilopascals, corresponding to all types of soil, the most mass universal row tractor Belarus 1020 had a maximum pressure of 150 kilopascals, which was 70 kilopascals higher than the permissible one for the corresponding crop shortage. They found that replacing ordinary tires with agrophilic tires could increase the area of the contact spot by 16 percent, while reducing the coefficient of unevenness and increasing the coefficient of use of the adhesion weight. The main condition for replacing ordinary tires with agrophilic tires was to keep the traction force unchanged.(Conclusions)Summarizing the results of the research as agrophilic direction, ensuring the compliance impacts on soil and positively solving the problems of saturation, it is possible to recommend the development of navigation systems in achieving utilization hitch weight equal to 0.5 (low tire pressure), equal to 0.6 (rubber joint with torsion bar suspension) and 0.7 (rubber track). It was found that the conducted research, taking into account the available data on traction tests of the T-250 tractor, would allow to include an agrophilic concept with a hypothetical dependence of the adhesion weight use factor on the longitudinal unevenness coefficient in the revised State Standard 27021-86 “Agricultural and forestry Tractors. Traction classes”.

Ground meat mixers mixing minced muscle tissue with other pre-formulated ingredients, are among the most common types of specialized meat processing equipment. The quality of minced meat, this being a food dispersed medium, including a solid, liquid and, in part, a gas phase, is determined by the dispersity and uniformity of its structure, as well as the uniformity of the distribution of components, that is, by the efficiency of the mixing process. The research carried out made it possible to theoretically substantiate the processes of mixing minced meat with the help of specialized technological equipment, including that providing vacuuming of processed food masses. A list of regulatory requirements for the structures of industrial meat mixers, which determine their technological efficiency, safety and hygiene, is given. Two main layouts of the specified equipment are described, horizontal and vertical. The design of a horizontal compact vacuum meat mixer with a coaxial double working spiral is presented. The results of work on the creation of a model range of vertical vacuum meat mixers are described, the possibility of using vertical vacuum machines for maceration by massaging medium-sized and small-sized meat raw materials is proven. It is advisable to carry out such a transformation of the equipment by replacing the working bodies of mixing with special massaging arms, these ensuring the most efficient performance of the specified technological operation. The diagram is presented, the design is described and the working cycle of the vertical vacuum machine with the geometric capacity of the working bowl is 0.15 m is described; the main technological and dynamic calculations of the said machine are given. The calculations made it possible to create an advanced non-metal-intensive design of a vacuum machine for mixing minced meat and/or massaging meat raw materials, which meets current requirements for equipment of the purpose. Studies of the quality of mixing of ground meat have shown that vacuuming makes it possible to consistently achieve a better density of minced meat, and for minced meat processed on an atmospheric mixer, a more uniform distribution of components was characteristic.

The article considers the problem of ensuring the sustainable development of industrial enterprises using the example of the Federal State-Owned Enterprise Kazan State Treasury Powder Plant. This issue is relevant for enterprises of all forms of ownership and sectors of the economy. To ensure sustainable development in difficult economic conditions, enterprises require managerial decisions and actions that must be taken ahead of schedule and taking into account all types of risks. In accordance with the concept of sustainable development, each management decision should take into account economic, environmental and social aspects. To ensure this strategy, enterprises currently use various quality management approaches, including the process approach, which is considered one of the most effective tools for improving business efficiency, plays an important role. The essence of this approach is that all the activities of the enterprise are considered as a set of processes, which are a combination of interrelated and interacting activities. Each process, in turn, has inputs that translate into outputs, resources, internal and external customers, suppliers, and other interested parties. Based on the study, the relevance of the application of quality management methods in the formation of the sustainable development strategy of the enterprise is substantiated. The application of the process approach is considered on the example of the production of paints and varnishes FKP "KGKPZ"; the importance of the quality management system for solving the task; demonstrated high achievements of the enterprise in the field of quality. Based on the results of the study, recommendations are made on the appropriateness of applying the process approach to the formation of a sustainable development strategy and achieving the strategic goals of industrial enterprises.

The article discusses the heat exchange of radiation of bunches of round finned tubes with the environment and the exhaust shaft. The system of equations describing the entire set of primary processes that make up the radiation heat exchange of finned bundles is very complex mathematically; therefore, the calculations of radiant heat transfer are usually based on a number of simplifying assumptions with a involuntarily distortion of the real physical picture. The main methods for calculating radiation used in engineering practice, viz. calculation by the average angular coefficient and the zonal method are briefly considered. A refined zonal method for calculating the radiant component of the heat flow of a horizontal bunch of finned tubes with an exhaust shaft is proposed. An experimental study of single-row bunches of finned tubes with different annular steps S1 (64 and 70 mm) was carried out for small Reynolds numbers Re = 130–720 in a wide range of the determining temperature at the beam inlet (16–83 °C). The aluminum finning of the bunch tube had the following parameters: screw finning diameter d = 0.0568 m; diameter of the tube at the base d0 = 0.0264 m; height, step and average fin thickness, respectively, h = 0.0152 m, s = 0.00243 m and Δ = 0.00055 m. Air movement in the bunch was carried out by gravitational traction created by a rectangular exhaust shaft. The experimental bunch was installed above the shaft, and the air was preheated before entering the shaft, which allowed expanding the temperature range of the air at the entrance to the bunch. It was found that incorrect accounting for a bunch reemission with an exhaust shaft when calculating single-row finned bunches causes a decrease in convective heat transfer by 7–25 %.

Nowadays the world energy system faces numerous transitions and shifts of the existing socio-technical regimes towards higher sustainability. Along with it, the sustainable transitions are often being postponed, slowed down or rejected to avoid negative externalities that could threaten the system stability. In this study, we aim to reach the deeper understanding of the externalities of energy transitions and the vulnerability of energy systems under the influence of negative externalities caused by sustainable energy transitions. Using the Externality theory (Baumol, Oates), Sociotechnical transition theory (Geels), as well as Energy sustainability Trilemma Method for the evaluation of the sustainability of energy systems we argue that such externalities need to be treated (internalized, avoided) by special policy measures other than common (classical) ways which may cause slowing down of sustainability transitions and make extra barriers for them. Transitions to more clean and low-carbon energy systems using energy technologies such as solar, wind, small hydro, biomass, waste management, e-vehicles are in the scope of this paper. It classifies the wide range of policy methods (classical and new) being applied separately and simultaneously, and analyses their application in energy policies designing aimed to combat negative externalities of energy sustainability transitions worldwide, so they might be minimized by properly tailored energy policy in each particular case.

The results of a numerical study of the gas-dynamic and power characteristics of the exhaust compartment of low-pressure cylinder, including the last stage with a blade of 1100 mm length and the exhaust path, in terms of their interaction are presented. Numerical models of exhaust compartment variants, including steam extraction in front of last stage diaphragm, two steam suctions from the interring gap with a dehumidification chamber, above-band leakages, steam injection from the dehumidification chamber into the diffuser channel have been developed. The flow in each computational subdomain is described by the complete system of non-stationary Reynolds – Favre equations averaged by Navier – Stokes. Turbulent effects are described with the SST Menter model in the stage, and with the modified Spalart – Allmaras turbulence model in the path. The integration of system of equations was carried out using an author’s software package. The calculated subdomains were approximated by hexagonal grids. The solver used an implicit difference TVD-scheme of finite volumes of the 2nd order of accuracy based on the solution of the Riemann problem. A variant of the algorithm based on splitting the computational process for multiprocessor platforms was used in the calculation. The model of stage used an averaging the mass, momentum and energy fluxes in the circumferential direction in the interstage gap. One channel of the diaphragm with a pre-connected fragment, as well as one channel of the working ring and the flow in the branch pipe were calculated. Parameters were exchanged between the stage and the branch pipe on the basis of mass flow averaging. The calculations were based on a table model of wet steam in the approximation of equilibrium condensation. The variants of improvement of the flow part of the exhaust compartment were considered. A study of the operation of the compartment options for the nominal mode of the K-220-44-2M turbine of the Loviisa nuclear power plant was performed. The effectiveness of lowering the cap of the collecting chamber, controlling the flow using sheet ribs above the diffuser shell, expanding the collecting chamber in the plane of the horizontal connector, and ensuring the release of excess steam from the moisture removal chamber through the tangential slots in the lower half of the convex shell of the diffuser were analyzed.

At the international level, the problem of the need to increase the contribution of renewable energy sources to domestic electricity demand is highly relevant. Since the production of renewable energy sources is quite expensive, many countries are developing various state and market incentives for investment in such energy sources. One such incentive is renewable energy certificates. The role of these certificates in the development of global renewable energy markets is invaluable. They not only help businesses achieve their goals in the field of renewable energy, but also reduce consumer payments for other renewable energy development programs. This article analyzes the current trends in the use of renewable energy certificates in the world and identifies the prospects for their use in the Russian Federation. In addition, the author of the article studied the issue of cost-effectiveness of renewable certificates. In order to assess the positive economic impact of the application of the certification system, calculations have been made to reduce the financial burden on participants in the Wholesale Electricity and Power Market by taking into account the funds received from the sale of these certificates to reduce payments by market participants to generators based on renewable sources under the program of agreements on the provision of capacity for generating objects operating on the basis of renewable energy sources, from the date of the start of supply of electric energy and of the last planned facility until the date of the last payment under the power capacity agreement. In addition, the author of the article studied the need for renewable energy certificates not only to obtain reliable data on the use of renewable energy sources, but also to create efficient electricity markets using renewable energy sources around the world.

Introduction. The world market of instant drinks is a highly competitive environment. New mechatronic production systems can help food companies maintain their competitiveness: they determine process modes, analyze them, and choose the optimal parameters, thus increasing the efficiency of the whole food enterprise. Another problem is the low biological and nutrient value of the finished product. New biologically active instant drinks could solve the problem that occurs in conditions of unsocial hours and unbalanced diet. Products of plant origin contain a lot of useful substances. Amaranth flour increases the biological value of the final products. The research objective was to develop mechatronic systems that could be used to produce instant drinks fortified with amaranth flour at the granulation stage. Study objects and methods. The present research featured a new line of production of instant granular drinks fortified with amaranth flour. The study focused on the granulation section. A drum vibro-granulator with controlled segregated flows was used to make a hardware design of the granulation process. The granulation process often demonstrates an unstable particle size distribution, which is associated with non-uniform mixing of the dry bulk components with the binder solution. A mechatronic module can solve this problem. However, it requires detailed information about the process conditions. Results and discussion. The research determined the specific energy consumption on the operating and design parameters for the granulation process in the new drum vibro-granulator. The experiment made it possible to obtain the optimal process parameters and improve the quality of the finished product. The flow rate of the binder solution depended on the readings of the power consumed by the kneading body engine, which stabilized the system. The value of this parameter is so small that its direct regulation is technically impossible. The paper introduces a block diagram of a multi-circuit cascade system to control the quality of the mixture automatically. The authors installed a valve on the pipeline that feeds the binder fluid in the pressure tank. The valve made it possible to control the process with sufficient accuracy. Conclusion. In the new mechatronic module of the drum vibro-granulator, the quality indicators of the resulting mix depend on the amount of power consumed by the kneading body engine and on the level of the binder solution in the pressure vessel.

This paper provides an overview of methods for processing and recycling chicken droppings. Poultry farms are a source of litter formation in an amount much larger than the main products. The litter contains up to 80% organic matter, many trace elements, all essential amino acids, growth regulators, vitamins, nitrogen and phosphorus. According to the Federal waste catalog, fresh chicken droppings belong to the 3rd hazard class. Fresh dung contains a significant amount of weed seeds, helminth eggs and pathogenic microorganisms. Dung is a source of toxic gases-ammonia, hydrogen sulfide, methane, carbon monoxide. Without recycling, manure becomes a source of environmental pollution. Disposal of chicken droppings is a difficult issue for many farms. Modern trends in the processing and use of poultry manure: 1) direct application to the soil without additional treatment, 2) Processing by passive and active composting, 3) Vermicomposting, 4) Processing with the help of housefly larvae, 5) Dehydration and drying (mechanical, thermal, vacuum), 6) Pyrolysis at t = 450-550 °C, 7) Plasma gasification, 8) thermal depolymerization Technology, 9) Direct combustion in steam and hot water boilers, 10) Microbiological conversion, 11) anaerobic digestion in Methane tanks with the formation of biogas, 12) Dung as a component of compound feed for cattle. The considered technologies of utilization of bird droppings do not fully contribute to the preservation of the environment and production. At the present stage, the industry needs an environmentally friendly and cost-effective biotechnology for processing manure, which makes it possible to turn organic waste into valuable raw materials for obtaining feed, fuels, fertilizers, and substrates for the chemical and microbiological industries. The future of waste management is in nature-like technologies, because in nature, all the necessary processing mechanisms are already in place.