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UTILIZATION OF PHOSPHOGYPSUM IN THE MANUFACTURE OF BUILDING PRODUCTS
Authors: D.D. Babaev, K.S. Petropavlovskii, V.A. Danyakin, V.B. Petropavlovskaya, T.B. Novichenkova
Abstract: In the article we considered the possibility of using industrial waste from the chemical industry – phosphogypsum – as part of raw mixtures with a complex of modifying additives. These additives were introduced in order to improve the physical, mechanical and operational characteristics of the composite binder based on phosphogypsum. It has been established that the introduction of mineral additives affects the properties of phosphogypsum stone – strength and average density. The strength of the hardened stone increases if a rationally selected composition of the raw material mixture with a plasticizing additive is used. It helps to reduce the water demand of the composite binder and increase its strength.
Keywords: phosphogypsum, gypsum binder, modifier, hyperplasticizer, strength. water demand.
CONSTRUCTION BIOCOMPOSITES USING
WOODWORKING WASTE. PART 1 (OVERVIEW)
Authors: V.V. Belov
Abstract: The methods of using woodworking waste, the prospects for their use as aggregate for light concretes and other building materials have been studied. Possible technologies for production of construction materials based on chemically and mechanically activated wood aggregate are considered. It has been shown that many of these technologies are quite complex and do not allow obtaining materials with high construction and technical properties. At the same time, it is concluded that provided that unconventional methods of activating wood aggregate are found, including through the use of biotechnology techniques, these wastes, the density of which is significantly lower than the density of traditional aggregates, can serve as an excellent raw material for the production of light concrete and help reduce the cost of extracting natural resources and energy for their processing.
Keywords: woodworking wastes, sawdust concrete, wood aggregate, properties, technology.
INFLUENCE OF GYPSUM CONCRETE REINFORCEMENT TYPE ON ITS PROPERTIES
Authors: P.A. Kalyaskin, V.B. Petropavlovskaya, T.R. Barkaya, K.S. Petropavlovskii, T.B. Novichenkova
Abstract: The article is an overview of the methods of reinforcement of gypsum concrete. Modern construction requires a constant search for new efficient, environmentally friendly and low-cost components. Gypsum materials can meet these requirements. Currently, they are widely used for interior finishing works, for the production of enclosing structures and decorative elements. Composite gypsum materials are among the most advanced building components, due to their cost-effectiveness due to the widespread use of gypsum, environmental friendliness, fire resistance, ease of installation and low energy consumption of production, but they have a number of disadvantages, such as fragility and low mechanical characteristics, which limits their further use. The reinforcement of gypsum materials significantly increases the strength characteristics, but the creation of composite materials based on gypsum is one of the developing and little–studied areas in the field of materials production. This review serves as a basis for further research on ways to improve the characteristics of gypsum-based materials using various reinforcements to expand the scope of use of gypsum products and gypsum-based building mixes.
Keywords: gypsum concrete, reinforcement, regulation of properties.
ANALYSIS OF THE IMPACT OF ELECTRIC VEHICLES ON THE FUNCTIONING
OF THE POWER GRID INFRASTRUCTURE OF THE CITY
Authors: K.B. Korneev, M.S. Khrustalyova, V.V. Sizova
Abstract: It is indicated that the transition to electric vehicles has made it necessary to significantly reconstruct the power supply network of cities. It is concluded that the presence of high-power charging stations has a huge impact on the schedule of power consumption of cities. The reasons that prevent the introduction of charging stations using renewable energy sources in the Russian Federation are listed. It is noted that the gradual expansion of the electric vehicle fleet will require amendments to regulatory documents regulating the technical, environmental and economic aspects of the functioning of the urban environment.
Keywords: electric car, power supply, load schedule, charging stations, urban infrastructure.
NETWORK INFLUENCE ON REACTIVE POWER
Authors: I.P. Popov
Abstract: The results of the evaluation of the influence of the transformer cascade on the reactive power in the network under symmetrical load are presented. A number of important conclusions are presented: in the considered scheme, with a symmetrical load, reactive power self-compensates; if the transformers are identical, then the reactive power flow from the load is divided between them into equal parts; the reactive power flow in the external section is three times less than in the internal one. It is indicated that in a real network, due to the above circumstances, the reactive power flow decreases significantly with an increase in the number of transformer substations as it moves away from the load.
Keywords: oscillator, energy, oscillations, reactive power, phase, cascade, transformer, network, symmetrical load.
ENERGY EFFICIENT SYSTEM OF AUTOMATIC CONTROL OF POWER TRANSFORMER COOLING
Authors: D.A. Prokofev, V.V. Okuneva, K.B. Korneev
Abstract: The factors leading to inefficient operation of transformer cooling systems, in particular autotransformers, are described. There are 8 types of cooling systems that are used depending on the power of the transformer, the power losses that occur during its operation. A general view of the DC type transformer cooling system is given. The consequences of maintaining low oil temperatures, taking into account the characteristic loading of transformers, are indicated. It is concluded that the introduction of software and hardware complexes for controlling the cooling system using electronically switched motors will make it possible to increase the cooling efficiency, the resource of transformers, reduce energy consumption, and therefore reduce the economic costs of its maintenance.
Keywords: cooling system, automatic cooling control, energy efficiency of substations, electronically commutated motors, software and hardware complex.
STUDY OF EFFECTIVE CATALYTIC PROCESSES FOR OBTAINING AROMATIC PRECURSORS IN THE SYNTHESIS
OF BIOLOGICALLY ACTIVE SUBSTANCES
Authors: Yu.A. Belousova, N.V. Lakina, V.Yu. Doluda, E.D. Stepanov, K.E. Soloviev
Abstract: The conditions of effective transformation of aliphatic alcohols in the presence of ZSM-5 type catalysts have been studied. It is concluded that in order to obtain the largest amount of aromatic C6+ fractions necessary for the formation of biologically active substances, it is necessary to carry out the transformation process at a temperature of 450 ° C; the highest concentration of the C5–C6 phase (39.5 wt. %) is achieved at an aliphatic alcohol supply rate of 0.3 ml/min, the lowest (15.5 wt.%) – at a rate of 0.15 ml/min.
Keywords: synthesis of hydrocarbons, zeolite, catalytic transformation, aliphatic alcohols, aromatic hydrocarbons.
STATISTICAL ANALYSIS OF OBSERVATIONS
THE PRECIPITATIONS ACIDITY IN TVER
Authors: F.V. Kachanovsky
Abstract: Analysis had made of dynamics of the precipitation acidity (atmospheric precipitation had fallen in Tver in 1990–2022 years). Time series models of the indicator pH and her evolution were examined. Qubic model have considered as adequate. Trend, cyclic component and seasonal indices of the indicator pH preserved his character in spite of time series lengthening.
Keywords: аcidity, acid rain, precipitation, model, time series, trend, cyclic component, seasonal component, residuals, indicator pH.
EFFECT OF IRON CONCENTRATION IN THE CATALYST ON THE FISCHER – TROPSCH SYNTHESIS
Authors: M.E. Markova, A.A. Stepacheva
Abstract: The effect of iron concentration in a bimetallic Fe-Ru catalyst on the Fischer – Tropsch synthesis (FTS) process, CO conversion and product selectivity has been studied. It is concluded that the catalytic systems with an iron content of 2 and 3 wt. % were found to be the most active in liquid-phase FTS. It was revealed, that CO conversion was calculated as 27 mol. % for one cycle in the presence of the chosen catalytic systems. In this case, the selectivity toward C5–C11 liquid hydrocarbons exceeded 95 mol. %.
Keywords: synthesis gas, Fischer – Tropsch synthesis, catalysts.