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Vol. 4 Issue 3

Archives Journal Chemical Bulletin Vol. 4 Issue 3

FORMATION OF NANOCOMPOSITE CARBON MATERIALS WITH BIMETALLIC NANOPARTICLES FOR AUTONOMOUS ENERGY SOURCES

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 5-12 p.
Abstract
The development of highly efficient autonomous energy sources allows for stable and uninterrupted power supply of physical and chemical processes and industries under various operating modes. Modern technological methods and approaches to the production of nanostructured electrode materials, as well as the elucidation of the features of the mechanisms of electrochemical reactions based on platinum metal nanoparticles make it possible to design control sensors, fuel cells and electrolyzers with increased energy characteristics. Carbon nanotubes used to create nanostructured electrodes in chemical energy converters have high functional properties compared to other matrices and, modified with nanoparticles with a reduced metal content, can increase the electrocatalytically active electrode surface area and achieve maximum fuel cell power parameters. In this work, the formation of bimetallic nanostructured composites with a variable composition on carbon carrier matrices for the construction of electrodes of autonomous current sources was carried out. Single- and multi-wall carbon nanotubes were chosen as substrates. To obtain composites, bimetallic platinum-palladium nanoparticles with different metal ratios were synthesized. The materials were studied by electron microscopy and X-ray phase analysis. As a result, an optimal algorithm, a synthesis method and conditions for creating nanocomposites with minimal particle sizes are established. The molar ratio water:surfactant changing, as well as the ratio of precursor metals, it is possible to obtain bimetallic platinum-palladium nanoparticles up to 12 nm. The data on the influence of the formation metal nanoparticles conditions on their size, shape and distribution over the matrix surface had been obtained. A series of prototypes has been formed for practical use in the design of current sources.
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APPLICATION OF A DYNAMIC FILTRATION UNIT WITH A MODIFIED TITANIUM FILTER FOR ELECTROLYTE PURIFICATION IN A HIGH-VOLTAGE GALVANIC SYSTEM

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 13-21 p.
Abstract
The development of functional nanodisperse materials based on porous template matrices is an urgent problem in the design of new devices in the processes of electrolysis of generation of "green" hydrogen, to increase energy saving of alternative energy sources, highly sensitive sensors for chemical technology, as new catalysts for afterburning automobile exhaust, in micro- and nanoelectronic devices. In this regard, the development of technology for the production of such materials, as well as studies of the relationship between the structure and catalytic properties of nanofilament matrix synthesis materials, seem relevant. A method of dynamic filtration of solutions using self-cleaning filters with continuous high-voltage processing of aluminum template matrices is proposed. Purification of aqueous solutions consists in the deposition of suspended aluminum salts on the working surface of titanium filters modified with an organofluorine component. The undoubted advantage of the proposed approach to the filtration process is the possibility of continuous removal of aluminum salt sediment from both the outer and inner surfaces of modified titanium filters due to a combination of cavitation created by built-in ultrasonic emitters and rotation of filter elements. The rotation of the filter elements allows you to direct the flow of liquid almost perpendicular to the flow passing through the filter. As a result, a tangential filtering mode is implemented, which prevents clogging of the filter. In addition, when the filter elements rotate, a partial transfer of torque to the liquid is carried out, due to which the liquid swirls around the filter elements. The swirling of the liquid causes a centrifugal effect of displacement of aluminum salts from the liquid layers adjacent to the filter elements, preventing clogging of the filter. The proposed filtration method for high-voltage electroplating of an aluminum matrix provides voltage and current density stabilization and the formation of ordered cylindrical nanoscale structures with a high aspect ratio.
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FEATURES OF THE STATE OF MINERAL METABOLISM IN PATIENTS WITH CHRONIC RENAL FAILURE AT THE INITIAL AND TERMINAL STAGES OF THE DISEASE

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 22-33 p.
Abstract
The problem of mineral metabolism in chronic renal failure is becoming a public health problem in all countries of the world, which is associated with an increase in the overall survival of this category of patients. We have carried out a comprehensive study of mineral metabolism and some biomarkers of bone metabolism in the initial and terminal stages of chronic kidney disease. At the same time, we examined not only the baseline values, but also the indicators after the treatment. It was determined that after treatment some stabilization of the studied parameters is noted, however, in most cases of observations, they remain higher than in the control group. Based on the above literature review, our statistical data and their comparisons with the studies of other authors, we are more inclined to the concept of using a complex of biomarkers in the study of the state of mineral metabolism in patients with chronic kidney disease.
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REMEDIATION OF SOILS CONTAMINATED WITH Cd2+ IONS BY ZOO COMPOST AFTER CULTIVATION OF HERMETIA ILLUCENS FLY LARVAE

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 34-45 p.
Abstract
One of the most toxic substances entering the soil due to anthropogenic impact is cadmium (Cd). When growing agricultural plants on soils contaminated with cadmium, it is possible for cadmium to enter the human body through food chains, which can cause numerous disturbances in the work of various body systems. In order to reduce the adverse effects of heavy metals on environmental objects, soil remediation is necessary. One of the types of remediation is a decrease in the mobility of pollutants and a decrease in their activity. In this paper, the possibil-ity of reducing the mobility of Cd2+ ions by adding zoo compost to contaminated soils after cultivating larvae of the “Black Soldier” fly (Hermetia illucens) was investigated. It was found that the content of Cd2+ ions in the mobile form in soils with the addition of zookompost significantly decreases compared to the control (up to 73.3% with a zookompost content of 2.5%). The sorption capacity of the zoo compost with respect to Cd2+ ions was determined, which is 0.12 mmol/g. The resulting sorption isotherm was processed within the framework of the monomolecular sorption models of Langmuir, Freundlich, Dubinin-Radushkevich. The values of sorption energy and Gibbs energy are calculated, the values of which indicate the course of spontaneous physical adsorption with chemisorption ele-ments.
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BIODESTRUCTIBLE POLYMER COMPOSITE MATERIAL BASED ON ARTIFICIAL LATEX AND BIO-FILLER

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 46-55 p.
Abstract
The study aims to create biodegradable composite materials based on non-emulsion polymer latexes with natural fillers. The article provides an analysis of the current state of the issue on the methods of obtaining and the state of the market of biodegradable polymer materials. The results of research on the development of a method for obtaining biodegradable polymer materials based on 1,4-cis-polyisoprene non-emulsion polymer latexes are presented. The paper develops recipes for the obtaining of artificial latex of isoprene rubber, a latex composition based on it, and also experimentally determines such technological parameters as the concentration of coagulant, the dipping mode of porcelain molds, the drying temperature of latex gel and vulcanization of films. During research has been proved the ability of the created polymer composite products to biodegradation under the influ-ence of biotic factors. Stimulation of biodegradation processes occurs due to the natural fillers of wood flour and coffee oil cake introduced at the latex stage in the form of pre-prepared suspensions. The developed technology makes it possible to obtain, using the method of coagulant sedimentation, composite polymer thin-film materials with adjustable operating time, makes it possible to reduce the load on the environment after the disposal of used products by burying them into the soil at polygons. The obtained polymer composite materials can be used to ob-tain dipped articles, for example, gloves for household, pharmaceutical, and chemical purposes.
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ADSORPTION OF HEAVY METAL IONS BY BENTONITE MODIFIED WITH CARBON NANOTUBES AND ACTIVATED WITH ACID

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 56-66 p.
Abstract
At present, there is no doubt about the need to search for new, more advanced methods and means of treating industrial wastewater. The adsorption method is one of the effective methods for purifying the aquatic environment. One of the sorption materials is bentonite, modified in different ways (by roasting, adding organic components, etc.). Laboratory studies were carried out on the bentonite of the Sarigyukh deposit (Republic of Armenia). The adsorption capacity of bentonite modified with carbon nanotubes with roasting at a temperature of 550°C and subjected to activation with HCl acid was investigated experimentally. It was found that acidic (HCl) activation of bentonite modified with carbon nanotubes and calcined at 550°C promotes an increase in its adsorption activity towards nickel (II) and cadmium (II) ions. The degree of adsorptive extraction of nickel (II) ions after activation of the specified adsorbent with HCl increases by 10%, and the degree of adsorptive extraction of cadmium (II) ions after a similar activation increases by 11%. The characteristics of the efficiency of adsorption of nickel (II) and cadmium (II) ions under static conditions were found with bentonite modified with carbon nanotubes and fired at 550°C, subjected to acid activation with HCl and without it. Bentonite modified with carbon nanotubes, calcined at 550°C and activated with HCl acid showed the greatest adsorption effect with respect to the ions of these metals. Its parameters: in relation to Ni 2+ ions: СОЕ = 852.0 mg-eq/g, Kd = 243.42 mg/dm3, S = 95.4%; to Cd2+ ions: COE = 950 mg-eq/g, Kd = 263.89 mg/dm3, S = 92.0%. The results of laboratory studies made it possible to recommend bentonite modified with carbon nanotubes, fired at 550° C and activated with HCl acid as a sorption material for purifying wastewater from nickel (II) and cadmium (II) ions.
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MINERALOGICAL COMPOSITION OF CLAYS OF THE «POLYANA» FIELD AS POTENTIAL SORPTION-ACTIVE MATERIALS OF INORGANIC ORIGIN

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 67-76 p.
Abstract
This work presents the results of a study of the phase (mineralogical) composition of clay from the Polyana field, Shebekinsky district, Belgorod region. To study the morphological and structural features of the mineral components that make up the specified clay, a set of methods of scanning and transmission microscopy, electron microdiffraction and energy dispersive analysis were used. Electron microscopic examination of Polyanskaya clay showed that it is composed of such minerals as: calcium and magnesium-iron form of montmorillonite, muscovite, low-temperature trigonal quartz, illite and ruthyl. More often than others, the preparations contain particles identified as montmorillonite, differing in structure without shaped edges and having a layered structure (layer thickness of about 1 nm). Particles of this mineral show a high tendency to aggregation, but at the same time they are quite easily split along the cleavage plane during dispersion, and therefore have a developed specific surface area, which determines good sorption characteristics.
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INTENSIFICATION OF THE COAGULATING SUSPENSION EFFECT ON THE EMULSION OF LIPID CONCENTRATE IN WATER

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 77-85 p.
Abstract
The coagulation treatment method is widely used for the effluents of various origins treatment. Substances-coagulants disrupt colloidal formations and contribute to the small particles aggregation, which leads to their precipitation and, as a consequence, a decrease in the organic substances content and the solution turbidity. The most widely used for this purpose are coagulants based on iron and aluminum. The Hermetia illucens insect is increasingly used to obtain chemical raw materials and valuable feed products for the poultry and fish cultivation. Production processes generate effluents contaminated with biodegradable substances, including components of larval fat. In this work, it was studied the coagulation purification possibility of fat-containing effluents from the production of lipid concentrate from the Hermetia illucens fly larvae by a coagulating suspension obtained from the electric arc steel-making furnaces dust, together with a co-coagulant – chestnut leaves carbonized at 400° C, which were used to increase the number of coagulation centers in the system.
The use of a coagulating suspension in the purification of model emulsions gives a low clarification effect (49% with the addition of 0.2 cm3 per 100 cm3 of the emulsion). It was found that the addition of finely dispersed carbon-ized leaves can significantly increase the cleaning efficiency. The best result was obtained by adding the carbonized chestnut leaves in an amount of 0.3 g together with 0.2 cm3 of suspension per 100 cm3 of liquid, while the clarification efficiency of the lipid concentrate model emulsion was 98%, at a pH of 8.
The main stage of coagulation occurs in the first 40 minutes of interaction, after which no changes are observed in the state of the system under study.
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INACTIVATION OF NITROFURAN DERIVATIVES BY FENTON REAGENT

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 86-94 p.
Abstract
The result of human evolution and the development of industry was the emergence of global environmental problems on the planet. Pharmaceuticals is one of the rapidly developing industries and, as a result, a "major supplier of pollutants" to the environment. The search for methods to solve the problems of purification and inactivation of organic toxic pollutants is an important task of modern chemistry. The purpose of this study was to study the inactivation of drugs of the nitrofuran group by hydrogen peroxide in the presence of iron (II) ions.
The study of oxidative degradation of furacilin and furagin preparations by Fenton reagent was carried out. The effect of different concentrations of the oxidative system on the destruction of drugs was compared, optimal conditions for destructive processes were determined. The characteristics of the oxidative degradation of the two drugs are compared, the justification of the differences based on the chemical structure of the active substances is proposed.
The effectiveness of the Fenton system for the destruction of nitrofuran class drugs has been confirmed. Chemi-cal methods of destruction of organic pollutants are advanced and can be used for wastewater treatment of medical and pharmaceutical enterprises, as well as for local treatment facilities.
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PHYTOSTIMULATOR FROM THE WASTE OF CULTIVATION OF THE BLACK SOLDIER FLY

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 95-105 p.
Abstract
The main chemical and sanitary indicators of waste formed during the cultivation of the fly Hermetia illucens were determined. The compliance of chemical and sanitary indicators with the requirements for waste for their use in agriculture is shown. Various methods for preparing a phytostimulator have been tested, the simplest and most effective method has been chosen - with the help of aqueous extraction. Proposed method allows to develop non-waste technology for production of biologically active substances. Based on data on the productivity of the growing process, phenological features of the development of primarily cereal and oilseeds after treatment with a phytostimulator, it can be concluded that it is advisable to use a phytostimulator obtained from Hermetia illucens fly cultivation waste.
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