bluuebunny/crossref_metadata_2025 huggingface dataset:
Methods of obtaining hypericaceae herb extract for the food industry
Authors: Drannikov A. V. , Shevtsov A. A. , Dombrovskaya Y. P. , Derkanosova A. A. , Kitaev D. S. , Kleymenova N. L.
Published: September 2023

Hypericaceae herb contains biologically active compounds, flavonoids (1.5–5%), naphthodianthrons, phloroglucins, tannins (10-13%), essential oil (0.1–0.33%) and other compounds. In accordance with the patent RU 2,067,452 C1, St. John's wort extract is obtained using a solvent system acetone-70% ethanol – 30% ethanol. Hypericaceae is extracted with acetone. The raw materials remaining after extraction are dried and extracted with 70% ethanol at a ratio of 1:10 by percolation. The extracts obtained from the extracts are combined and dried. Extracts of St. John's wort herb can be obtained using a two-phase solvent system. As an extraction system, a mixture of solvents is used - chloroform: ethanol: water (8:10:10). There is the following way. Solvents are used in ethanol, methanol, isopropanol (each in a concentration of 40%, 70% and undiluted) and in water, using ultrasound. Samples are extracted within 15, 30 and 60 minutes. Extraction in water using ultrasound is comparably close to screening with alcohols in terms of the percentage of biologically active components given off, but does not require purification. For food production, the method of obtaining St. John's wort herb extract according to the patent RU 2 265 448 C2 will be relevant. Where the laser-treated mass is suspended in water. Suspension is carried out so that for 1 liter of water there are from 50 to 300, preferably from 100 to 250 g of laser-treated mass of St. John's wort grass. The suspension of crushed plants should be carried out at a temperature of 10 to 40 ° C, although higher or lower temperatures are not excluded. Then the suspension is kept from 5 to 20 days, preferably from 7 to 15 days at a temperature of 2 to 10 ° C, preferably from 4 to 8 ° C. Food products enriched with St. John's wort herb extract have longer shelf life.
Evaluation of barley accessions on the content of antioxidants in grain in the conditions of Eastern Siberia
Authors: Polonskiy V. I. , Sumina A. V.
Published: September 2023

The aim of the study is to determine the adaptive potential of barley accessions by the total antioxidant content (TAC) in the grain and 1000 grain weight, as well as to analyze the relationship between these traits of barley, on the one hand, and the adaptability indicators of accessions for them, on the other. The object of the study was 10 accessions of hulled barley, which were grown under the conditions of Eastern Siberia in three ecological points: Krasnoyarsk Territory, Republic of Khakassia and Republic of Tyva. The HTC values for these items were respectively: 1.50, 1.25, 0.93. In barley accessions, the TAC value was determined using the Tsvet Yauza-01-AA device; gallic acid was used as a reference sample. According to these two traits of barley accessions, 5 indicators of their adaptability were calculated: the coefficient of ecological variation Cv, the stress resistance index d, the homeostatic parameter Hom, the indicator of the level and stability of the variety PUSS, the parameter of the selection value of the variety Cs. It was found that the highest level of TAC in the grain was characteristic of the Uvatsky and Acha accessions. Biom and Abalak accessions positively stood out in terms of grain size. It is shown that the optimal values of the adaptability parameters and their smallest sum of ranks in terms of the TAC value in the grain were characteristic of the accessions Acha and Biom, and those in terms of the weight of 1000 grains were noted in the same accession of Takmak barley. It was found that the relationship between the average values of TAC in the grain of barley accessions and the indicators of their stability of variety stability indicator and Cs for this trait was positive and significant. The presence of a positive relationship between the average value of 1000 grain weight and the stability parameter Cs for the specified feature was statistically proven. The demonstrated result may indicate that when sampling barley for an increased value of TAC in grain, the stability of the manifestation of this trait under different growing conditions is likely to increase.
Mathematical modeling of snacks drying process from minced fish in a fluidized bed
Authors: Kosachev V. S. , Ostrikov A. N. , Yashonkov A. А.
Published: September 2023

A mathematical model of snacks drying process from minced fish in a fluidized bed with distributed parameters of the heat exchange process between the surface of an anisotropic body and the environment is proposed. The solution of the problem of non-stationary heat transfer by heat conduction using the Galerkin method is considered. The trial and verification functions of the method used, implemented in the PTC MathCAD engineering calculation environment, are linearly independent, represent the first elements of a complete system of polynomial functions and satisfy the boundary and initial conditions. Theoretical and experimental studies have been carried out, which allow considering the process of drying snacks from minced fish in a fluidized bed and scientifically substantiate options for its improvement. According to the results of experimental studies, the adequacy of the obtained mathematical model is shown. It is proved that with a uniform initial temperature distribution during preheating, the temperature inhomogeneity increases up to the moment of a phase transition on the surface of dried object. The importance of taking into account the preheating phase of wet material is established, since at this stage a temperature profile is formed, which is characterized by significant heterogeneity. This is especially important, since temperature heterogeneity directly affects the quality of the food product. The possibility of taking into account anisotropy in heat transfer processes using a three-dimensional mathematical model of transport with distributed parameters is confirmed. The developed technique allows significantly increasing the accuracy of an anisotropic boundary value problem solving by replacing the operation of integrating the stiffness matrix elements with a system of differential equations by algebraic formulas.
Exponential smoothing of dynamic series liquefaction number of corn starch mixture
Authors: Shmalko N. A. , Nikitin I. A. , Velina D. A. , Khayrullin M. F.
Published: September 2023

The most important statistical indicators of the time series are the absolute chain and basic growth, chain and basic growth rates, growth rates, etc., which describe the current state of the process without making a forecast. The classical approach to forecasting series is based on the choice of a suitable theoretical model of the trend with unknown parameters, followed by its modeling. The applicability of the exponential smoothing method to the investigated dynamic series lies in the possibility of predicting a non-stationary time series, in which the weight of the series member decreases exponentially and practically does not have any effect on the value of the exponential average, which replaces the observed value of the series. The aim of the work was to carry out exponential smoothing of the dynamic series of the liquefaction number of the corn starch mixture. In this case, the study presents a sequence of observations of the index of liquefaction, ordered depending on the increase in the dosage of amylopectin corn starch in the corn starch mixture. The liquefaction number for corn starch mixture consisting of fine corn flour (GOST 14176) and corn amylopectin starch (GOST 32159) in the ratio: 100:0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80, 10:90, 0:100 were received by calculation. Exponential smoothing of the dynamic series of the liquefaction number of corn starch mixture makes it possible to obtain a reliable forecast of the dynamics of the quality indicator at the liquefaction process in the specified interval. The standard errors of the predicted values of the liquefaction number of corn starch mixture at a dosage of amylopectin corn starch in a mixture from 0% to 35.0 % inclusive are within the convergence requirements of GOST 30498 (ISO 3093) for measurement results. A stable growth in the dynamics of the number of liquefaction of corn starch mixture is provided when replacing corn flour with amylopectin corn starch in an amount of not more than 35.0 %.
Analytical time series alignment liquefaction number of corn starch mixture
Authors: Shmal N. A. , Nikitin I. A. , Velina D. A. , Khayrullin M. F.
Published: September 2023

The statistical description of the development of dynamic processes in time is carried out using time series. To eliminate random fluctuations and build an analytical function of the trend of the time series, an analytical alignment procedure is used. The choice of the type of the trend function is carried out by the method of finite differences, the calculation of the trend parameters ‒ by the method of least squares. The purpose of this work was the analytical alignment of the time series of the liquefaction number of the corn starch mixture obtained in the experiment on the PChP-99 device. The mechanism of starch gelatinization with a given liquefaction rate under such conditions requires additional theoretical and experimental study. Calculations have shown that the process of liquefaction of starch gel corresponds to the exponential trend equation: y = a • ebt, which is a particular case of an exponential trend. It has been experimentally established that an increase in the proportion of amylopectin starch in a corn starch mixture leads to an increase in the maximum viscosity of the resulting gel when the swelling water-starch suspension is heated. In the process of further gelatinization of corn starch mixture with an increase in the proportion of amylopectin starch, the strength of the gel decreases due to the preservation of the mobility of water molecules during the transition in the sol-gel system, which contributes to an increase in liquefaction number. Experimental data do not contain anomalous values; the error in approximating the regression equation for the trend of the time series is less than 5 %. The statistical significance of the coefficients of the linearized trend equation is proved in favor of the hypothesis of the existence of a time series. The obtained estimates of the regression equation make it possible to use it for predictive purposes, providing an accuracy of up to 95.42 % of the total variability of the liquefaction number in the absence of autocorrelation of first-order residues. Checking the normality of the distribution of the residual component according to the RS test showed the adequacy of the trend model, the hypothesis of the absence of heteroscedasticity according to the Spearman and Goldfeld-Quandt tests is accepted.
Development of a composition of functional plant raw materials for the prevention of diseases associated with potassium deficiency
Authors: Kuizheva S. K. , Shalyakhov A. A. , Siyukhov K. R. , Tazova Z. T. , Lunina L. V.
Published: September 2023

The article presents the results of research on the development of a composition of functional plant raw materials designed to enrich various groups of foodstuffs for the prevention of diseases associated with potassium deficiency in the human body. Potassium deficiency or hypokalemia is one of the most frequent forms of electrolyte imbalance accompanied by severe organ and system disorders. Potassium deficiency occurs for a variety of reasons, but recently, according to numerous sources, there is a high frequency of hypokalemia in patients with coronavirus infection. Improvement of the availability of this macronutrient can be achieved primarily by increasing its intake into the body through specialized food products. As a natural source of potassium in the products of functional purpose it is advisable to use compositions of wild plant raw materials, the chemical composition of which contains a significant amount of potassium. Experimentally we have established such types of plant raw materials: common oregano (lat. Oríganum vulgáre, grass), black currant (lat. Ríbes nígrum, leaves), small bramble (lat. Lémna mínor, leaves), common blueberry (lat. Vaccinium myrtillus L, leaves), common thyme (lat. Thimus serpyllum L, grass). Designing the composition of the phytocomposition was carried out by the method of planning experiments for the composition of mixtures. By using the procedure Plan for surfaces and mixtures with the constraints of the module Planning experiments package STATISTICA 10 was generated plan of experiments, studies were conducted to determine the quantitative content of potassium in the experimental samples, carried out mathematical processing of the results obtained scientifically validated optimal component composition of the composition of plant raw materials, in which the potassium content is - 1072.8 mg/100 g (33.53% of the recommended daily intake), which meets the requirements of GOST P 52349-2005 and confirmed
Technological aspects of the preparation of jelly marmalade of reduced sugar content and caloric content using a natural carbohydrate-containing product
Authors: Magomedov G. O. , Plotnikova I. V. , Litvinova A. A. , Magomedov M. G. , Plotnikov V. E.
Published: September 2023

The article describes the characteristics and properties of natural honey varieties - buckwheat and sunflower. It also presents their comparative analysis of chemical composition, quality indicators, enzyme activity, antioxidant activity, vitamin C content and microbiological indicators. The innovative method of  sugar-free jelly marmalade production based on honey by injection molding into a polymeric barrier shell is described. It has been stated that the replacement of white sugar and starch syrup by natural honey in  jelly marmalade recipe leads to sugar and calorie content decrease of the product, an increase in its nutritional value, antioxidant activity, antibacterial properties due to the application with honey essential substances for a human body  (vitamins of group B, C, antioxidants, antiseptics, enzymes, minerals, etc.). The use of a new method of forming and marmalade packaging  in a polymer barrier shell leads to an extension of marmalade shelf life up to 6 months. Analysis of changes in the quality of jelly marmalade samples showed that moisture removal, and with it the process of drying after storage for 180 days, occurs more intensively – 2.2 times in a sample of marmalade packed according to traditional technology, while the content of reducing substances (to the total mass of dried marmalade) in this sample increased by 11.3 %. Daily consumption of the developed product helps to increase immunity, vitality, it normalizes metabolism, strengthens heart muscle, nervous system, it also improves food absorption, work of the gastrointestinal tract, etc. The developed dietary marmalade can be recommended primarily to children during their growth, the elderly people, athletes and adults with heavy physical exertion, obese as well.
Investigation of the fabrication of nanofibers from aqueous polyvinyl alcohol solutions by electrospinning
Authors: Lebedeva A. V. , Vu N. T. , Olekhnovich R. O. , Morozkina S. N. , Uspenskaya M. V.
Published: September 2023

Polyvinyl alcohol (PVA) refers to polymers that have great potential for medical and technical applications. Especially, the possibility of its medical application in nanofibres is of great interest due to its good water solubility, high biocompatibility and non-toxicity. PVA is used for various pharmaceutical and biomedical purposes, as a carrier for the delivery of proteins and drugs, as dressings, filter materials, and as artificial organs. Currently, many drug delivery systems have been developed, such as hydrogels or complex electronic microchips. Nanostructural materials are particularly advantageous for rapid drug release due to their high surface area to volume ratio. Both natural and synthetic polymers can be used to produce nanofiber materials, but the combination of different polymers (synthetic and natural) and the incorporation of various biologically active substances into them provides special properties to the finished materials. In this work, the properties of aqueous solutions based on polyvinyl alcohol were investigated: electrical conductivity, viscosity and pH. The influence of technological parameters of electroforming process on obtaining nanofibers from aqueous solutions of PVA. The optimum PVA concentration for the formation of nanostructures was determined equal to 8 wt.%. At this concentration, the PVA solution has electrical conductivity, viscosity and pH equal to 571 µS/cm, 107.23 mPa·s and 6.14 respectively. As part of the study, the electroforming process parameters were obtained to enable the production of nanofibers with a diameter of about 170 nm: distance between needle and collector 140 mm, spinning solution feed rate 0.2 ml/h and voltage between needle and collector 30 kV.
Experimental study of the flow structure in packed tray-type column extractors
Authors: Berengarten M. G. , Kozin Y. V.
Published: September 2023

Liquid extraction is a well-known separation process that has been widely used in the chemical industry for many years, for example, in the selective purification of oil fractions, in the purification of liquefied gases from hydrogen sulfide, in the production of petrochemicals, in the recovery of metals, in nuclear fusion, in food and pharmaceutical industry. On-going elaborations aimed at engineering solution search in order to improve mass-transfer processes are in progress on a permanent basis. Combination of trays and packing in the fractionator results in stream disequilibrium which leads to worse hydrodynamic conditions in the splitter (extraction, rectifier tower and etc.) and causes significant difficulties in stable operating process maintaining.  The study objective is to review the structure of stream structures in the extraction tower via examples of trays and packing combinations since the mentioned contact devices are widely used in industry but they are conventionally applied as individual contact devices and not in combination. Combination of the above contact devices may earn a supplementary synergetic effect. In the course of the experiment it was found out and described in graphic format that stream disequilibrium could be eliminated and hydrodynamic conditions in the extraction tower could be improved via extra stream supply in the tower shell. Research will be useful for the development of new designs of column equipment, for example, extraction. In order to expand the experiment in various hydrodynamic modes, it is proposed to simulate the experiment using, for example, the Solid Works 2020 software package and, in particular, one of its add-ons - Flow Simulation.
Harmful effects of e-waste on human health
Authors: Agayev B. S. , Abdullaeva M. Y.
Published: September 2023

Today, waste electrical and electronic equipment has lead a number of global problems and their solution is as urgent as other environmental problems. The article explores the issues related with potential danger of e-waste to human health. Definitions of some important terms on e-waste are given related with topic of the article are given. Reference is made to the international E-waste Directives (these terms are absent in the environmental law of the Azerbaijan Republic). In countries the selective waste collection which are not used classified, the main e-waste disposal types and their characteristics is shown in the article. Moreover, an example of recycling of some harmful and dangerous electronic waste in Azerbaijan is given. Collected, systematized and classified information from a number of international normative documents and journals. The expediency of carrying out the classification of waste according to the criterion "hazardous-safe" has been substantiated. The main goal of the study is to identify the causal relationship between hazardous waste and their deterimental effects. Four related factors- hazards components, harmful environment which they, cause dangerous effect to human health and pathology. In the preparative the article, general methods and techniques of the systemic approach as well as scientific analysis and synthesis, were used in comparison and generalization of the results. As an information base of the article, materials of a number of international normative acts and normative acts of the CIS countries and authoritative journals on this topic were used. The results of the research can be used by specialists dealing with the problems of e-waste, students studying the subjects " Ecological engineering ", "Ecology and Life Safety", as well as those who are interested in healthy lifestyle and safety.
Improvement of the adsorption-absorption vapor recovery unit for cleaning the gas-air mixture from volatile organic compounds and hydrogen sulfide when loading naphtha on marine tankers
Authors: Meshalkin V. P. , Babakov E. A.
Published: September 2023

The article proposes the improvement of adsorption and absorption plants for the recovery of naphtha vapors through the use of a sulfur compounds purification unit. This unit allows you to remove environmentally hazardous sulfur components from naphtha vapors, which adversely affect adsorption filters, without increasing the temperature and significant pressure drop of the gas-air mixture. The relevance of the study is due to the fact that marine terminals are objects of significant emissions of hydrocarbons and sulfur compounds. Intensive evaporation of naphtha during the filling process leads to air pollution and loss of valuable product. Vapor recovery units with a desulfurization unit are designed to solve the problem, however, their implementation at loading facilities requires the installation of additional flow stimulators and, as a rule, additional electricity consumption. The main purpose of the study was to find ways to improve environmental safety and improve adsorption and absorption vapor recovery units at existing sea tanker loading facilities, taking into account the current level of their technical equipment. It established that the use of the proposed desulphurization unit makes it possible to expect a reduction in energy consumption due to the absence of flow stimulators (gas blowers), as well as an increase in the operation of adsorption filters by 35-45%. The effectiveness of modeling the purification of low-pressure gas from hydrogen sulfide has been confirmed by studies on a laboratory installation including a desulfurization reactor. Purification of gas from hydrogen sulfide using a chelated iron complex ensures the conversion of hydrogen sulfide into sulfur, while the residual content of hydrogen sulfide can be reduced to less than 1 ppm. The implementation of catalytic purification by a chelated iron complex in a disk film apparatus makes it possible to purify the gas-air mixture from hydrogen sulfide impurities.
Increasing the strength and water resistance of materials based on poly-vinyl alcohol with boric acid
Authors: Studenikina L. N. , Domareva S. Y. , Golenskikh Y. E. , Matveeva A. V. , Melnikov A. A.
Published: September 2023

Polyvinyl alcohol (PVA) is a promising polymer for the production of materials with desired properties, primarily water solubility and biodegradability. The main reason for limiting the use of film materials based on PVA is the lack of a mechanism for regulating the rate of their dissolution. Purpose of work: evaluation of the strength characteristics and water resistance of PVA films and PVA:MC composites when crosslinked with boric acid, depending on the amount of borate introduced into the polymer matrix. The objects of the study were 8 experimental samples: No. 1 - a film of unmodified PVA grade KurarayPoval 3-83, plasticized with glycerin, obtained by pouring from a 5% solution; No. 2-4 - PVA films modified with boric acid in various amounts, obtained similarly to sample No. 1; No. 5 - a plate of PVA:MC composite (50:50 wt.%), obtained by liquid-phase combination of PVA unmodified with boric acid and microcellulose dispersion, followed by dehydration in air; No. 6-8 - plates of the PVA:MC composite (50:50 wt.%), obtained on the basis of PVA modified with various amounts of boric acid, similarly to sample No. 5. As a result of the study, it was found that the modification ("crosslinking") of PVA grade KurarayPoval 3-83 with boric acid is accompanied by an increase in the viscosity of PVA (which manifests itself in the clouding of the films during dehydration), an increase in strength indicators in proportion to the amount of borate ion introduced into the PVA polymer matrix, but at At the same time, the water resistance of the modified PVA films increases to a certain limit of the borate content (in particular, with the introduction of 0.075 and 0.15 ml of boric acid per 1 ml of PVA, the films did not dissolve within 1 week of exposure to water at t = 20 °C, but with the introduction of 0.30 ml of boric acid per 1 ml of PVA, the film dissolved in 3 hours of exposure, for comparison, unmodified PVA of the specified brand dissolves in water at n.o. for 10 minutes).
Quantum-chemical modeling of reactions initiating sulfuric vulcanization of isoprene rubber
Authors: Soloviev M. E. , Vlasov V. V. , Pushnitsa A. S. , Karmanova O. V.
Published: September 2023

The quantum-chemical method of the density functional DFT B3LYP / 6-311G ** have been used for calculation of thermodynamic functions and changes in the total electronic energy during the initiation of sulfur vulcanization of isoprene rubber using the N - cyclohexyl - 2 benzthiazolyl sulfenamide accelerator in the presence of atmospheric oxygen. Since sulfur, in the process of vulcanization of rubber compounds, is in a larger amount in a dissolved state, unlike oxygen, it is concluded that in the presence of sulfur, the formation of a valid vulcanization agent (DAV) will occur, and oxidation will occur to a lesser extent. When comparing the values of the reaction energy with the addition of the S8 molecule, it was found that sulfur in the accelerator radical acceptance reactions is a more active acceptor than oxygen in similar reactions. The effect of the number of sulfur atoms on the activity of the radicals of the sulfidating complex arising upon the acceptance of sulfur by the radicals formed during the decay of the accelerator is analyzed. It was found that the cyclohexyl radicals of the accelerator are the most active, however, in subsequent reactions of DAV with rubber, the radicals of DAV obtained with the participation of benzthiazolyl fragments are more active. The study of the effect of the number of atoms on the energies of the reactions of the formation of persulfhydryl suspensions shows that the primary suspensions are most likely to contain 8 sulfur atoms formed in reactions involving biradicals formed during the decay of the eight-membered ring of a sulfur molecule
Evaluation of fatigue strength of carbon fiber reinforced plastics (CFRP) with various types of hybrid matrices
Authors: Kosenko E. A.
Published: September 2023

Polymer composite materials (PCM) have found wide application in various industries due to the ability to create low-weight products with specified operational properties. During operation, composite products are exposed to static and cyclic loads, climatic and many other factors. Evaluation of the fatigue strength of composite materials and the influence of various additives and modifiers on it is an urgent scientific and practical task. The article describes the technology of obtaining PCM with various types of hybrid matrices formed by the main binder material and the material representing an independent "liquid" phase in the composite structure. Based on the analysis of the kinetics of curing, anaerobic polymer material (Loctite 638), silicone elastomer (Unisil-9628) and synthetic wax were selected as the materials of the components of the "liquid" phase. Fatigue strength assessment tests were carried out by applying cyclically varying tension-compression loads to the samples. The load during cyclic tests was 70% of the static tensile strength of the samples. The residual strength was evaluated by testing the tensile strength of the samples until complete destruction after cyclic loading. The results of fatigue strength tests of carbon fiber plastics with various types of hybrid matrices (formed by various components of the "liquid" phase) are presented. The analysis of the results showed that the use of an anaerobic polymer material as a component of the "liquid" phase of the hybrid matrix makes it possible to increase both the initial static strength of the material (by ~ 1%) and the residual strength after cyclic loading (by ~ 11%) compared with these indicators obtained during the testing of control samples. After performing cyclic loading, carbon fiber plastics with anaerobic polymer material and silicone elastomer have an increase in residual strength compared to previously performed static tensile tests by ~ 8% and ~13%, respectively. The use of an anaerobic polymer material and silicone elastomer as a component of the "liquid" phase makes it possible to increase the modulus of elasticity of carbon fiber plastics after cyclic loading by ~ 13% and 5%, respectively, compared with the results of preliminary static tests.
Improving the performance of equipment for countercurrent extraction on the basis of process simulation
Authors: Alekseev G. V. , Shanin V. A. , Birchenko A. A. , Kravtcova E. V. , Goncharov M. V.
Published: September 2023

The article discusses the possibility and efficiency of using discrete diffusion in the extraction of materials with an internal anisotropic structure in comparison with a continuous diffusion process. For this purpose, theoretical calculations were made and experimental studies of countercurrent extraction of pectin from Jerusalem artichoke were carried out. To carry out the simulation, an equation for calculating the coefficient of internal diffusion and an equation for the adsorption isotherm during countercurrent extraction were determined. Evaluation of the efficiency of using countercurrent extraction to obtain pectin from Jerusalem artichoke was carried out by considering the influence of the effect of discrete diffusion on the rate of the process. The resulting equations made it possible to analytically evaluate the efficiency of discrete diffusion from two-zone spherical particles in comparison with continuous diffusion in multistage extraction of plant material. Having analytical data on the distribution of extractable substance concentrations in the inner and outer zones of the particle at different stages of extraction, it is possible to calculate the diffusion coefficients of materials in different zones and theoretically determine the degree of destruction of cell walls and structures at different stages of extraction. The developed technique, thanks to the analytical description of the process, allows you to select the optimal conditions for the extraction of various materials from plant and animal raw materials.
The use of modified "neodymium" polybutadiene in the formulation of the outer lining of conveyor belts
Authors: Yartseva T. A. , Karmanova O. V. , Mikhaleva N. A. , Tkachev A. V.
Published: September 2023

Currently, in the formulations of conveyor belts, polybutadiene rubber used with a content of up to 50 mass parts to improve the strength and wear resistance of rubbers. The results of a study of the properties of covering rubber compounds and rubbers based on a combination of polyisoprene, styrene-butadiene copolymer and polybutadiene used for the manufacture of conveyor belts were presented. The use of modified "neodymium" polybutadiene (SKD-ND-M), in the preparation of which a polyfunctional heterocyclic compound was used as a modifier, was proposed in the formulation of the lining of conveyor belts. This sample was characterized by an increased content of 1,4-cis units, a narrow MWD and a Mooney viscosity at the level of rubbers obtained without a modifier. We used serial brands of rubbers obtained on different catalytic systems: titanium (SKD) and neodymium (SKD-ND) as reference samples. A significant reduction in energy consumption in the manufacture of rubber compounds based on modified rubber in comparison with the rubber compound based on SKD was noted. It has been established that the use of SKD-ND-M instead of SKD made it possible to achieve an improvement in the technological properties of rubber compounds and their vulcanization characteristics, to ensure the required level of physical and mechanical properties of vulcanizates and performance indicators of lining rubbers. An improvement in the tear resistance of rubbers, as well as in compression set at 100°C and 125°C, when using modified "neodymium" polybutadiene in the lining rubber formulation instead of SKD rubber, was revealed. Replacing SKD-ND with a modified analogue provided a reduction in the abrasion rate of the conveyor belt lining, which will positively affect the increase in the service life of products based on it.
Evaluation of the stiffness index of carbon fiber reinforced plastics (CFRP) with a hybrid matrix
Authors: Kosenko E. A.
Published: September 2023

One of the most important characteristics of structural materials is their stiffness. Ensuring the required stiffness is the key to durability and efficient operation of the structure. Variation in the compositions of polymer composite materials (PCM), the introduction of various additives and modifiers into their structure leads to changes not only in the operational properties of composites, but also in their stiffness. Achieving a positive effect on a number of some properties can lead to the loss of others. This article describes the technology of forming polymer composite materials with a hybrid matrix. The peculiarity of these materials is that the hybrid matrix is formed by two materials, one of which (the main binder) is completely cured after molding, and the second retains its "liquid" state and represents a separate phase in the composite structure. Such PCM have a variable stiffness of material, which makes it necessary to experimentally study the effect of the quantity and location scheme of the "liquid" phase component on this indicator. The technology of the laboratory method for determining the stiffness of PCM samples is described, which consists in measuring the maximum deflection of a flat sample under the action of a statically applied load. The measurement was carried out on carbon fiber reinforced plastic samples with a hybrid matrix formed by an epoxy binder and a silicone elastomer. The influence of the amount and location scheme of silicone elastomer in the composite structure, as well as the scale effect on the maximum deflection was evaluated. The amount of silicone elastomer was taken in a total of 0.25 mL and 0.50 mL in all locations, varying the number of locations and their direction relative to the length of the sample. It was found that the longitudinal location of silicone elastomer in PCM samples leads to the greatest decrease in their rigidity. The amount of silicone elastomer in the location zone does not significantly affect the change in the stiffness of the samples. Increasing the number of layers of reinforcing fabric by 2 times allows to reduce the deflection of the test samples by 7–10 times depending on the applied load. Doubling the width of samples and silicone elastomer locations results in a 2-fold reduction in maximum deflection. With an increase in the thickness of PCM in samples with silicone elastomer, the values of maximum deflection under the action of various statically applied loads are similar to the values of this parameter of carbon fibers of the same thickness without a component of the "liquid" phase.
Ecological and economic assessment of violations of regulatory requirements for the protection of water bodies
Authors: Plotnikova R. N.
Published: September 2023

The issues of ecological and economic assessment of the consequences of violation of regulatory requirements for the protection of water bodies are considered. A comparative analysis of the current methods for determining the amount of damage caused to water bodies in violation of water protection requirements and the amount of prevented damage to water resources as a result of the activities of environmental authorities has been carried out. It is shown that the standard of payment for a ton of toxicant entering a water body, depending on the values of maximum permissible concentrations, is essentially similar to the coefficient of relative ecological and economic danger of a pollutant discharged into a water body, also depending on the values of maximum permissible concentrations of toxicants and their hazard classes. It is established that the indicator of specific damage to water bodies can be comparable with the coefficient characterizing natural and climatic factors and the indicator depending on the multiplicity of excess of the concentration of the toxicant in the discharge above its background concentration in the water body. A fairly close convergence of the calculated data on determining the amount of damage in accordance with the methodology for assessing damage to water bodies due to violations of water legislation and the amount of the fee for exceeding the permitted discharge has been established. Maximum deviations were noted for the toxicological groups of low-risk toxicants. The coefficients of adaptation of the financial assessment of damage to water bodies caused as a result of emergency discharges of pollutants and the amount of damage caused as a result of violation of water protection requirements are obtained.
Economic prospects of PR communications in the field of tourism
Authors: Glagoleva L. E. , Zatsepilina N. P. , Kovaleva E. N. , Zatsepilina L. S. , Sandberg A. B. , Sekhniev M. E.
Published: September 2023

This article reveals the economic prospects of using PR communications as a tool to improve the effectiveness of marketing services in the tourism sector. The ways of increasing user interest in travel agency websites and increasing the conversion of the project through contextual advertising, as well as other ways to increase the attendance of websites of organizations in the field of tourism are considered. The metrics of web analytics are considered, showing the economic efficiency of advertising based on the development of PR communications, since for the competent promotion of a tourist product, it is necessary to be able to analyze business metrics in order to assess the economic efficiency of business processes: what kind of advertising brought sales and revenue, how best to allocate the budget, which PR communication turned out to be unprofitable and should be abandoned. Therefore, it is so important from the point of view of modern trends in the economy to take into account and consider the main criteria for the effectiveness of PR communications and the prospects for their implementation in the tourism sector as the main type of advertising for the consumer. The article discusses the specifics of the promotion of services on the Internet, which allows taking into account the individual characteristics of each client. This is due to the fact that identifying the target audience is very important, because it allows the company to achieve marketing goals as profitably as possible. This inevitably leads to lower costs and profit due to the economic efficiency of the advertising campaign.
Evaluation of labor productivity by value added criterion
Authors: Nuzhdin R. V. , Khorev A. I. , Karpovich M. A. , Lukina O. O. , Melnichuk V. N.
Published: September 2023

The process-value analysis of labor results is focused on the assessment of the level, structure and dynamics of added value, which is considered as the main source of achieving the interests of personnel, owners and the state. When assessing the proportions of value added distribution that ensure the parity of interests of key stakeholders, as a rule, the mass of mandatory payments generated in the form of value added tax is underestimated. The main goal of this study is to adapt existing methodological approaches to evaluating the results of the work of personnel of telecommunication companies in order to improve their analytical suitability based on evaluation procedures that ensure the realization of the benefits of process cost business analysis. The developed methodological approach is based on distributed value added assessment. In particular, the following are evaluated sequentially (in five stages): 1) the share of value added in total income, taking into account receipts from other types of activities; 2) the level of income of the staff, as the basis for increasing the motivation and quality of work; 3) the share of personnel income in value added and mandatory payments generated during its creation; 4) the level of labor productivity; 5) the ratio of the rate of dynamics of productivity and wages. In order to increase the reliability of the conclusions based on the data of the process-cost analysis of labor results, three zones of interest were identified (by the number of key stakeholders), for each of which corrective operations are provided that provide not only the possibility of conducting a retrospective analysis, but also predicting the possibility of parity of interests. Approbation of the proposed assessment procedures was carried out based on the materials of three telecommunications companies in the Voronezh region for 2017-2019. Based on the results obtained, a conclusion was made about the possibility of creating services with high added value, an adequate level of remuneration for the personnel of telecommunication companies at the regional level, and certain disproportions in the distribution of value added. The expediency of a criteria-based assessment of the dynamic ratio of labor productivity and its payment is proved when the required level of results is achieved at the previous stages of the assessment.
Analysis of the preferential effects of the use of asynchronous electric motors in the industrial sector
Authors: Armashova-Telnik G. S. , Bobovich T. A.
Published: September 2023

The relevance of the article is due to the specifics of the design of asynchronous electric motors associated with high demand, in production, in electric machines. To date, the development of the state is actively seeking to reduce the use of internal combustion engines. To ensure this transition, countries are creating new charging stations for electric vehicles. The share of sales of electric motors is continuously growing every year. According to Rosstat for 2019, the purchase rate of electric vehicles is 2.5%, in 2020 - 4.6%, and in 2021 - 6.4%. Currently, the market of ready-made electric motors is not able to meet the production demand. In addition, knowledge of the design features of asynchronous electric motors, the ability to navigate certain market trends, will allow you to make informed management decisions in the production and promotion of products. Also, the use of asynchronous electric motors in the production activities of business entities allows not only to increase the competitiveness of the enterprise, through resource minimization, but also to respond to modern needs in compliance with environmental safety requirements. The article discusses the advantages and features of the use of various types of electric motors in production. The specific conditions of their effective use are highlighted, with different capacities, production volumes, etc. Statistical analysis of the use of asynchronous electric motors in the Russian industry demonstrates data that form the prospects for the development of this type of production, which will contribute to the growth of economic indicators in the Russian market for the production of environmentally friendly technological solutions.
Russia's digital economy: an analysis of the pandemic period of the national and regional economy
Authors: Sibirskaya E. V. , Oveshnikova L. V. , Pasynkova O. M.
Published: September 2023

The pandemic has affected almost all spheres of life of modern civilization. One of the technological forms of overcoming this global problem is digitalization, which is a window of opportunity to get out of the crisis. Society had to quickly rebuild itself in the conditions of the compression of traditional markets, the replacement of a number of professions with automated systems, and the growth of cybercrime. In responding to these challenges, the issues of digital economy analysis presented in this study come to the fore. o study the development of the digital economy, the following quantitative indicators were selected: the proportion of organizations using digital technologies, the number of personal computers in the surveyed organizations, including those with access to global information networks, the proportion of organizations using the Internet, data on the use of information and communication technologies in organizations by type of economic activity, the proportion of organizations using special software, as well as data on the use of information and communication technologies in organizations by collective classification groupings of economic activities. As a result, it was revealed that Russia lags behind the leading countries in terms of the level of development of the information society and the digital economy. The most popular digital technologies turned out to be cloud services, which relieve companies from the need to create their own digital infrastructure for data storage. The tendency of reduction of personal computers by organizations and the share of enterprises using software has been revealed, which indicates the predominantly remote nature of work during the pandemic. The importance of investing in the installation of specialized software and training personnel to work with software and digital literacy is noted. The coronavirus pandemic as a whole has helped Russian companies to begin restructuring their business organization towards digitalization. Institutions that ensure the development of the Russian digital economy are encouraged in almost all government programs and activities aimed at improving information and communication technologies and creating conditions for the use of digital services in business.