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Quantum model of anharmonic vibrations of a diatomic molecule with a variable force constant and a small value of the anharmonicity coefficient

https://doi.org/10.58224/2619-0575-2024-7-1-22-31
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 22-31 p.
Abstract
In this work, vibrations of a diatomic molecule are considered within the framework of quantum mechanics as an anharmonic oscillator with small values of the anharmonicity coefficient. Based on well-known models of quantum harmonic and anharmonic oscillators, a new model with a variable value of the molecule force constant was created here. The force constant depends on the vibrational quantum number n and the anharmonicity coefficient . Mathematical analysis of this model confirmed its physical validity. As an example, the vibrational energy of an oxygen molecule was calculated within the framework of the model presented in the work.
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Application of thermal methods for the analysis of organic matter content in urbanozems

https://doi.org/10.58224/2619-0575-2024-7-1-32-40
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 32-40 p.
Abstract
Objectives: the purpose of the study is to determine the content of organic matter in anthropogenic soils using thermal analysis methods.
Methods. Physico-chemical methods of soil sample analysis were used, the actual acidity, ash content and or-ganic matter were determined according to GOST 26213-2021 and by thermogravimetric analysis.
Results. It is shown that the content of organic substances in soils by thermogravimetry and according to GOST 26213-2021 differ by no more than 15.4%, which, in particular, may be due to the decomposition of inorganic sub-stances during prolonged exposure at a temperature of 525 ° C according to the GOST method. Nevertheless, the thermogravimetry method provides information about the temperatures at which the maximum decomposition rate is observed.
Conclusions. It has been established that the methods of thermogravimetry and according to GOST 26213-2021 give different results of the content of organic carbon in the soil due to different temperatures of maximum decom-position of humic acids. The higher the maximum decomposition temperature, the less organic substances decom-pose when studying soils by thermogravimetry.
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Structural parameters of YBa2Cu3-xO6+y

https://doi.org/10.58224/2619-0575-2024-7-1-41-48
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 41-48 p.
Abstract
the aim of the work is to study the structural parameters of phase 1-2-3 by precision X-ray diffraction method. The refinement of composition and structural parameters to the divergence factor R = 0.008 was carried out. The composition of the substance can be expressed by the formula . Higher values of the mean-square amplitudes of atoms vibrations and vibration anisotropy were obtained for Си1 and О1 located in the basis plane z = 0. Comparison with data obtained at low temperatures suggests that the high mobility of Си1 and O1 is related to static displacements of atoms from their crystallographic positions. There is a correlation between the deviation from the oxygen stehiometry, the lattice period c and the value of the superconducting transition temperature Tc. An increase in the oxygen content is accompanied by an increase in Tc. Dependences of isotropic mean-square amplitudes of atoms-components vibrations of compounds on the oxygen content are plotted. For the O1 atom in the tetragonal phase, a marked growth of mean-square amplitudes of vibrations with increasing oxygen index is observed, which may be associated with an increase in the instability of the structure. It can be concluded that the analysis of precision diffraction studies for yttrium-barium-copper oxides allows us to identify the structural features responsible for the instability of this class of materials.
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Analysis of the effect of technological parameters on desulfurization of agglomeration charges

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 5-17 p.
Abstract
This paper presents an analysis of the influence of technological parameters such as temperature, basicity and carbon content on the degree of desulfuration (removal of sulfur) during agglomeration of iron ore raw materials, which in the future will help to detect and calculate the most effective mode of operation of firing conveyor and sintering machines during heat treatment and processing of mineral iron ore raw materials. It was found that the most significant effect on the desulfurization of fluxed sulfate-containing charges is to reduce the size of the ore and the introduction of fusible additives that reduce the viscosity of the slag. It was revealed that the effect of the first factor is limited by the capabilities of crushing departments of mining and processing plants and the difficulties of sintering fine-grained charges, and a decrease in the fusibility of the sintering charge can lead to a deterioration of combustion processes and a drop in the technical and economic indicators of the sintering process. Gorenje It was found that the implementation of additional measures to obtain low-sulfur agglomerate from sulfate-containing ores is hampered by the lack of research on the kinetics of the main reactions that determine the final sulfur content in the agglomerate. It has been shown that dissociation of calcium and barium sulfates in contact with silicon, iron and aluminum oxides is possible at temperatures of 1000-1100°C. It was found that the dissociation of sulfates proceeds at a rate that ensures an increase in the degree of desulfuration. A decrease in the degree of desulfurization is observed in the temperature range of1200-1300°C, due to liquid-phase contact with silicon, iron and aluminum oxides. It was found that further studies of the kinetics of thermally activated reactions of high-temperature dissociation of barite and calcium sulfate under conditions close to agglomeration processes in operating heat treatment units of iron ore raw materials are necessary to increase the degree of desulfuration of sulfate-containing fluxed agglomeration charges.
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The impact of environmental problems on epidemiological aspects and human health because of human industrial activity

 18-26 p.
Abstract
Industry is one of the main directions of economic development not only in the Russian Federation, but also in other developed countries of the modern world. Industry contributes to the acceleration of scientific and technological progress and the pace of economic development, improving the level of well-being of the population. Despite a number of objective advantages observed with the intensive development of industry, many problems caused because of industrial activity of a person. One of the most urgent problems of the subject area under con-sideration is environmental pollution and its negative impact on epidemiology and human health. The main pur-pose of the presented article is to complete an analysis regarding the impact of human industrial activity on epide-miological aspects and human health. Because of the work, the main factors that negatively affect the environmen-tal situation, as well as the relevance and necessity of reducing this influence in order to improve the epidemiologi-cal situation and human health, examined. Based on the considered factors, the author's approaches to ensuring environmental safety in the operation of industrial enterprises are formed. The practical value of the presented work consists in the possibility of applying such approaches in establishing a safe from the point of view of the eco-logical situation of the functioning of industrial enterprises.
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Surface-active and micelle-forming properties of binary mixtures of glycyrrhizin and decyl glycoside and stabilization of foam stabilized by such a mixture with xanthan and keratin additives

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 27-42 p.
Abstract
The surface and micelle-forming properties of two surface-active sugar derivatives and their binary mixtures were studied: dipotassium glycyrrhizinate, which is an anionic surfactant of natural origin (saponin) and has biologically active properties, and a nonionic sugar surfactant decyl glycoside. Decyl glycoside has a noticeably higher surface activity and a noticeably lower CMC value than dipotassium glycyrrhizinate. Using Rubin's equations, the composition of mixed micelles and the parameters of surfactant interaction in them were calculated. It has been shown that a synergistic effect is observed in aqueous solutions of binary mixtures of these surfactants. Due to this, dipotassium glycyrrhizinate can be used together with decyl glycoside as a base for foaming solutions for cosmetic, pharmaceutical and medical foams. Using dispersion analysis of foam over time, the stability of foam stabilized with a mixture of dipotassium glycyrrhizinate and decyl glycoside in a molar ratio of 0.2:0.8 and the ef-fect on the stability of foam of the addition of two different biopolymers: polysaccharide - xanthan (xanthan gum) and protein - keratin of sheep wool hydrolyzate were studied. Based on dispersion analysis of foam micrographs, it was shown that both polymers increase the durability of the foam over time. Foam containing xanthan breaks down primarily through Ostwald ripening rather than coalescence. Foam with keratin hydrolyzate has a lower initial dispersion and number of bubbles than foam with keratin hydrolyzate. The stability of both foams is close, but slightly higher in the case of the addition of keratin.
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A method for producing high-purity carbon material from plant waste

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 43-53 p.
Abstract
Сarbon materials are widely in demand, used in many sectors of human life. Due to their complex properties, they are indispensable both in industry or agriculture, and in environmental protection. However, the ecological and economic aspects of their production: the availability of primary raw materials and the cost of obtaining high-quality adsorbents sharply increase the cost of these products. On the other hand, a lot of plant waste is generated annually, estimated in Russia at several million tons. Organic fractions of municipal waste represent potential raw materials for thermal processing into carbon materials. This direction of their utilization allows us to solve two tasks at once – to obtain inexpensive high-quality carbon material and reduce the amount of waste of plant origin. In this work, the object of research was pre-dried rose flowers, which were crushed, heat treated at 450-500 °C for 4 hours, followed by multistage washing with hydrochloric and hydrofluoric acids and water. It is shown that the chemical purity of the product depends on the sequence and number of washing steps. The resulting carbonizate was characterized by relative purity (ash content 0.9 wt. %. with a carbon content of 84%) and satisfactory porosity, which, according to the test results for test substances – iodine and methylene blue (adsorption capacity for which is 35.5% and 45 mg·g–1, respectively), considered this material promising in wastewater treatment water treatment and other fields. For comparison, the article presents the quality indicators of activated carbon from birch wood of the BAU brand and a number of agricultural waste.
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Investigation of the features of sunflower oil emulsions and the effect of the emulsifier on the efficiency of sorption purification

 5-13 p.
Abstract
The emulsifying ability of surfactants is determined by the presence of hydrophobic and hydrophilic functional groups. The properties of the emulsifier affect the dispersed phase average size. Edible refined sunflower oil was used to prepare the emulsions. In the composition of oils, even after refining, small amounts of accompanying components are found after the plant tissues destruction. This allows the vegetable oil to be emulsified without surfactants addition. The article examined emulsions without the addition of surfactants and with sodium lauryl sulfate, as one of the most common components of detergents in the Russian Federation.
The purpose of the research was to study the colloidal chemical characteristics of vegetable oil emulsions in water and the influence of their properties on the efficiency of sorption purification. It has been shown that sodium lauryl sulfate in an amount of 0.05 mg/dm3 in the sunflower oil-water system leads to a decrease in the average diameter of oil droplets, as well as to a change in the ζ – potential of the oil micelle, from a weakly positive one it goes into a weakly negative region with an increase in charge as the emulsifier concentration increases. In the presence of an emulsifier, the efficiency of extraction of vegetable oils from aqueous media using the OSP600 sorp-tion material decreases.
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Analysis of physical and chemical processes of sulfur removal during agglomeration of ore raw materials

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 14-27 p.
Abstract
This paper analyzes the physical and chemical processes of sulfur removal during agglomeration of iron ore mineral raw materials to build a technologically efficient processing model. Thermodynamic aspects of the formation of sulfates are considered, taking into account the features of desulfurization of calcined ore materials in the presence of alkali-earth metal compounds in the charge of agglomerates, when sulfur dioxide is partially captured by them. It was found that the addition of limestone to concentrate and pure pyrite has no noticeable ef-fect on the removal of sulfur from the charge in the temperature range of 600-900 ° C during short-term firing due to the weak absorption of calcium carbonate by sulfur dioxide. Analysis of the agglomeration processes of sulfu-rous iron ore materials found that free lime absorbs sulfur well, since an intermediate stage is necessary for lime-stone absorption – dissociation of calcium carbonate. The factors contributing to decarbonization, which lead to a more complete removal of sulfide sulfur from oxidized iron ore materials, have been investigated. The thermody-namic analysis carried out by the authors allowed us to scientifically substantiate the experimentally observed in-tensification of the dissociation reaction of sulfates with an increase in temperature, a decrease in the partial pres-sure of oxygen in the furnace atmosphere during the processing of iron ore agglomerate. The data obtained in the study show that in oxidizing and slightly oxidizing conditions, sulfates decompose with increasing temperature if their contact with silicon and iron or aluminum oxides is ensured, and the formation of a melt accelerates mass exchange and promotes desulfurization. It is revealed that at the same time, liquid-phase sintering intensifies, in-hibiting the release of gases. In the conditions of the agglomeration process as a whole, the atmosphere is oxidiz-ing, although in some micro-volumes near the burning coke particles, the reducing potential of the gas phase is possible. Therefore, it makes sense to consider a uniform ratio between sulfate and sulfide sulfur in various gaseous environments.
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Overview of surfactant flooding as a method of increasing oil recovery and the applicability of microcapsulation technology to improve the efficiency of surfactant flooding

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 28-47 p.
Abstract
The problem of increasing the degree of oil recovery from reservoir formations has remained relevant over the past few decades.
Currently, there is a rapid increase in interest in chemical methods of increasing oil recovery to intensify oil production, in particular, flooding with surfactants (surfactants).
This article describes the factors affecting the efficiency of self-winding and the effect of adsorption on the eco-nomic component of the technology. To solve the problem of adsorption, preventing the large-scale introduction of surfactant, it is proposed to use the technology of microencapsulation of surfactants in a solid shell.
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