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FEATURES OF CHOOSING THE OPTIMAL CONFIGURATION
OF THE RIBBED DOME
Authors: T.R. Barskaya, S.A. Sokolov, A.S. Dvuzhilov
Abstract: The article discusses the calculation and design of dome structures, as well as the choice of optimal geometric parameters of the dome depending on the height of the boom and the degree of the sector of the ribs of the structure. The conclusions of the conducted research are presented.
Keywords: dome, coating, metal structures, optimal parameters.
SELECTION OF OPTIMAL GRAIN COMPOSITION
OF ROAD CONCRETE AGGREGATES
USING COMPUTER SIMULATION
Authors: V.V. Belov, М.А. Smirnov
Abstract: The difficult-to-reconcile requirements of high plasticity of concrete mixes and high performance of road concrete can only be met by applying scientific principles of forming a concrete matrix structure with the highest possible aggregate grain density, with continuous granulometry, and the use of a complex of additives (microfillers and chemical additives with plasticizing and air-entraining properties (to create reserve porosity)). To achieve this goal of forming a concrete matrix structure with the highest possible aggregate grain density, patented methods and computer programs developed at the Department of Production of Building Materials and Structures (PBS) TvGTU were used.
Keywords: micro level reinforcement, optimal granulometry, tightest particle packing, software package modeling
DEVELOPMENT OF SELF-REPAIRING CONCRETE
Authors: Yu.Yu. Kuryatnikov
Abstract: The problem of cracks in reinforced concrete can be solved by using self-healing concrete for the production of products and structures. The possibility of using and regulating the autogenous mechanism of self-healing in concrete has been considered. Research is aimed at enhancing this natural potential using special additives with pozzolanic activity.
Keywords: self-healing concrete, autogenous mechanism, mineral additives, and durability.
JUSTIFICATION OF THE OPTIMAL DESIGN SOLUTION
FOR THE INSTALLATION OF SUPPLY AND EXHAUST VENTILATION
IN A SINGLE-APARTMENT RESIDENTIAL BUILDING
WITH AN AREA OF UP TO 150 M2
Authors: A.V. Levikov
Abstract: The article analyzes the design solutions for the forced ventilation device for a residential building of a given layout using supply and exhaust ventilation and supply valves in the walls. The shortcomings and advantages of each design solution were revealed, in particular, significant difficulties in the use of plenum and exhaust plants in houses with an area of up to 150 m2. Proposed design recommendations for independent adjustment of the ventilation system in each individual room.
Keywords: ventilation, natural ventilation, forced ventilation, supply and exhaust ventilation, ventilation valve.
THE MODELS OF PARASITIC ANTENNAS IN UNITS
OF KEY SYSTEMS OF INFORMATION INFRASTRUCTURE TAKING
INTO ACCOUNT RESONANCE REGIMES
Authors: D.V. Komnatny
Abstract: The model of parasitic antennas in units of key systems of information infrastructure microelectronic apparatus is considered. The transfer functions method is used for electromagnetic noise susceptibility calculation. The resonance regimes and analogous to resonance regimes in electrically small antennas, which models are presented lumped-parameter circuits, are described. The transfer function expression for parasitic antennas with models in the form of distributed parameter circuits is obtained and regimes, analogous to resonance in loads are exposed. The method of enumerated regimes investigation during apparatus testing for stability to electromagnetic noise is discussed. The analysis of resonance regimes in parasitic antennas give the possibility o exclude the worsening of microelectronic apparatus electro-magnetic compatibility.
Keywords: electromagnetic compatibility, impulse noise, parasitic antennas, resonance regime, bandwidth, electrically small antennas, distributed parameters circuit, test impulses.
METHODS OF EXPLAINABLE ARTIFICIAL INTELLIGENCE
FOR POWER AND ELECTRIC POWER SYSTEMS: APPLICATION POSSIBILITIES
Authors: M.A. Kulikova, Ya.A. Chebotarev, O.N. Torgovanova, K.B. Korneev
Abstract: This paper examines the potential of explainable artificial intelligence (XAI) for energy and power systems using applications that use machine learning but do not yet use XAI.
Keywords: electric power, power system, neural networks, explainable artificial intelligence, XAI, machine learning.
TRAINING UNIVERSITY STUDENTS IN ENGINEERING, INNOVATIVE WORK BASED ON THE RESEARCH WORK PERFORMED
AT TVER STATE TECHNICAL UNIVERSITY.
PART I. THE PROBLEM OF TRAINING UNIVERSITY STUDENTS AND DESIGNERS IN HEAT TRANSFER CALCULATIONS
IN FURNACES, FURNACES, COMBUSTION CHAMBERS
Authors: A.N. Makarov
Abstract: The article presents the laws of thermal radiation of gas volumes of electric arcs in electric arc steelmaking furnaces (EASF) and torches in flare heating furnaces (FHF), furnaces of steam boilers (FSB) of power plants, combustion chambers (CC) of gas turbine units (GTU), gas turbine engines (GTE), discovered at the Department of Power Supply and Electrical Engineering of Tver State Technical University (TSTU). Part I of the article presents the problem of teaching university students to calculate heat transfer in EASF, FHF, FSB, CC of GTU, which existed in the 1950–1990s, before the discovery of the laws of thermal radiation of gas volumes. Based on the discovered laws, modern methods for calculating heat transfer in EAF, FBC, FBC, CC have been developed at TvSTU.
Keywords: scientific research, scientific discovery, heat exchange, radiation, furnaces, fireboxes, combustion chambers, students, training.
EVOLUTIONARY ALGORITHMS FOR OPTIMAL ENERGY CONSUMPTION:
A COMPREHENSIVE REVIEW AND ANALYSIS
Authors: Pavlova Yu.M., Korneev K.B., Korneev V.K.
Abstract: This paper presents a detailed review of various OPF problems and the wide range of algorithms – both traditional and evolutionary – employed to solve them, with a particular focus on the integration of wind energy and multi-objective optimization strategies.
Keywords: Optimal power flow, Classical algorithms, Evolutionary algorithms, Multi-objective problems, Renewable energy sources.
ADDITION TO THE THEOREM
ON THE n-SYMMETRY LINES OF A FLAT PLATE
Authors: Al.A. Shum, A.M. Vetoshkin
Abstract: The article is a continuation of the previous article by the same authors, in which the following theorem was proved: the moment of the n-th order of a convex flat plate relative to a straight line L, drawn parallel to a given straight line, reaches the smallest value when the straight line L is a line of (n – 1)-symmetry of this plate. In this article, the validity of this theorem is extended from the case of a convex plate to the general case of an arbitrary flat plate.
Keywords: moment of n-th order, line of n-symmetry, half-mass line, equilibrium line, flat plate, density function, mass, center of mass, electric machine.
ANALYTICAL FEATURES OF DETERMINING THE COMPOSITION
OF THE GAS PHASE OF THE REACTION MASS IN THE PROCESS
OF SYNTHESIS OF FORMALDEHYDE AND ITS DERIVATIVES
BY CATALYTIC TRANSFORMATION OF CARBON DIOXIDE
Authors: A.A. Kuragin, A.I. Pichugina, E.I. Laguseva, A.V. Starovoytov, K.V. Chalov, V.Yu. Doluda
Abstract: The article presents the results of developing a chromatographic method for analytical monitoring of reaction products for obtaining formaldehyde by transforming carbon dioxide. The research was carried out using a Crystallux-4000M gas chromatograph with a 5 m long, 2 mm internal diameter, packed column filled with MN-270 sorbent with a fraction of
70–120 μm. It was shown that the composition of the gas phase of the reaction medium includes hydrogen, methane, carbon monoxide and dioxide, formaldehyde, methanol, dimethyl ether, methylal, and trioxane. The influence of temperature and the linear velocity of the carrier gas on the efficiency of the analysis and the yield time of the components was determined. An increase in the column temperature leads to a decrease in the analysis time from 15 to 10 minutes, as well as to a decrease in the selectivity of the separation of chromatographic peaks. The linear velocity of the carrier gas also has a significant effect on the efficiency of separation of the components of the analyzed mixture, with the maximum separation factors of the chromatographic peaks being achieved at 0,25–0,28 cm/min. Based on the results of the studies, it can be concluded that it is necessary to use a temperature programming mode to ensure high selectivity in the separation of individual substances.
Keywords: formaldehyde, chromatography, analysis, analysis conditions, temperature, linear velocity, separation selectivity.
STUDYING THE EFFECT OF REACTION PARAMETERS ON CATALYTIC OXIDATION OF GLUCOSE USING Pt/Al2O3
Authors: A.I. Petrova, D.Y. Tsvetkov, N.V. Lakina, V.Yu. Doluda, M.G. Sulman
Abstract: Heterogeneous catalysis is the basis of most large-scale industrial chemical processes. The relevance of glucose oxidation by catalytic methods is driven by several key factors that relate to the production of valuable chemicals, the use of renewable raw materials, and environmental sustainability. Heterogeneous catalytic oxidation of glucose offers several advantages over traditional enzymatic methods, although enzymatic methods also have their own merits. Heterogeneous catalysts are generally more stable than enzymes. They are less sensitive to changes in temperature, pH, and the presence of inhibitors. Heterogeneous catalysts can be easily separated from the reaction mixture and regenerated for reuse. This reduces the cost of the process and the amount of waste generated. The purpose of this work is to investigate the features of the catalytic oxidation of glucose, analyze the reaction mechanisms, and evaluate the impact of various factors on the efficiency of the process. This paper presents the results of varying the conditions of glucose oxidation using a 3%Pt/Al2O3 catalyst to achieve optimal selectivity and conversion, 77,63 and 72,71 %, respectively.
Keywords: heterogeneous catalysis, catalysts, oxidation, glucose.
RESEARCH OF PHOTOINITIATED COPOLYMERIZATION
OF METHYL METHACRYLATE AND ACRYLONITRILE RESINS
FOR ADDITIVE TECHNOLOGIES
Authors: A.I. Pichugina, A.S. Sozontova, N.Yu. Starovoytova, A.V. Ustimov, V.Yu. Doluda
Abstract: Research of the processes of photo-initiated copolymerization of resins based on methyl methacrylate and acrylonitrile for 3D printing by LCD technology. Obtained the basic physical and chemical characteristics of model samples based on the studied compositions. Using the IR-Fourier spectroscopy method, obtained and analyzed data of the main stages of the curing and post-curing process of photopolymers. Found the optimal parameters of printing in UV to prevent the destruction of the polymer and preserve its structural properties.
Keywords: photopolymer resin, degree of curing, methyl methacrylate, acrylonitrile,
IR-Fourier spectroscopy.
FEATURES OF CATALYTIC OXIDATION OF L-SORBOSE
ON PLATINUM CATALYSTS
Authors: D.Y. Tsvetkov, A.I. Petrova, N.V. Lakina, V.Yu. Doluda, M.G. Sulman
Abstract: Catalytic oxidation of carbohydrates, such as sorbose, is an important process in the chemical and biochemical industry. Sorbose, being a sugar, is widely used in the production of vitamins, sweet additives, and other food products. However, in order to effectively use sorbose in various chemical processes, its structure must be transformed, which can be achieved through catalytic oxidation. The features of catalytic oxidation of sorbose on heterogeneous catalysts include the selection of an appropriate catalyst, the reaction conditions (temperature, pressure, and solvent), and the mechanisms of interaction between the catalyst and the substrate. The aim of this work is to investigate the features of the catalytic oxidation of sorbitol on various heterogeneous catalysts, to analyze the reaction mechanisms and to evaluate the influence of various factors on the efficiency of the process. The consideration of these aspects will allow to gain a deeper understanding of the potential of sorbitol use in chemical processing and to develop new approaches to its catalytic transformation. In this work, two heterogeneous platinum catalysts known from the literature were used in the oxidation of sorbitol under equal reaction conditions. All samples were analyzed using HPLC. Selectivity with respect to 2-keto-l-gulonic acid was determined based on these analytical data.
Keywords: oxidation of sorbitol, catalytic oxidation, heterogeneous catalysts.