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CHEMISTRY

ISSN 2227-6017 (ONLINE), ISSN 2303-9868 (PRINT), DOI: 10.18454/IRJ.2227-6017
ЭЛ № ФС 77 - 80772, 16+

QUANTUM CHEMICAL CALCULATIONS OF THE ELECTRONIC CHARACTERISTICS OF THE ACTIVE CENTERS OF THE DEPRESSOR-DISPERSING ADDITIVE IN AVOGADRO SOFTWARE

Posted in 2021, CHEMISTRY, Issue № 02(104) February 2021 | 0 comments

The aim of the current study is to develop a 3D model of a depressor-dispersing additive in order to evaluate its active centers using the PM3 quantum chemical calculation method (a parametric method based on the integral approximation of the neglect of the differential diatomic overlap) in the Avogadro software package as well as to propose the mechanism of action of the additive and the implementation of this interaction in the software. The quantum chemical modeling was carried out in the Avogadro software package using a semi-empirical method for calculating the electronic structure of PM3 under standard conditions of 273 K and 0.1 MPa. The study conducts a quantum chemical calculation of the electronic characteristics of the active centers as well as calculates the nucleophilic and electrophilic centers with charges (– 0.5700 C. for the oxygen atom in the carbonyl group) and (0.6590 C. for the carbon atom in the carbonyl group). A 3D scheme of the interaction mechanism of a copolymer molecule of ethylene and vinyl acetate with n-paraffin crystals is constructed.

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ADSORPTIVE REMOVAL OF FORMAMIDE WITH ACTIVATED CARBON

Posted in 2021, CHEMISTRY, Issue № 02(104) February 2021 | 0 comments

The current article examines the adsorption of formamide from aqueous solutions on active carbons and determines the features and mechanism of the adsorptive interaction. At the same time, the study determines the parameters of adsorption, the limiting stage of mass transfer and calculates the mass transfer coefficient required for engineering calculations. The calculation has found the dynamic characteristics of the adsorption process: the dynamic capacity; the speed of movement of the working area; the duration of the fixed bed; the length of the working layer; the amount of purified water before slipping. The article presents the results of optimization of the process of adsorptive removal of formamide with industrial activated carbon AG-OV-1 by mathematical modeling using data from statics, kinetics, and dynamics as well as proposes the scheme of the hardware design of the technology of adsorptive removal of formamide.

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TECHNOLOGY OF ADSORPTION REMOVAL OF MERCURY IONS FROM AQUEOUS SOLUTIONS

Posted in 2021, CHEMISTRY, Isssue № 01(103) January 2021 | 0 comments

The study carries out a comprehensive research on the adsorption extraction of mercury ions from model aqueous solutions with modified active carbon. As an adsorbent, the study used activated carbon, which is a waste product of caprolactam production at the stage of wastewater treatment. To increase the adsorption activity, the activated carbon was subjected to a modification process. The research explores the parameters of the porous structure and the main changes in the chemical state of the activated carbon surface caused by the processes of use in the production of caprolactam and further modification. The study shows a significant decrease in the porous structure and redistribution of micropores into mesopores as well as an increase in the content of nitrogen-containing surface functional groups. The adsorption of mercury ions was studied under static and dynamic conditions. For a more comprehensive characterization of carbon sorbents and calculation of adsorption parameters, the study uses the theories of monomolecular adsorption. The research confirms the efficiency of using the modified sorbent both experimentally and theoretically and carries out the study of its kinetic features. The study defines the main adsorption parameters necessary for the engineering calculation of the adsorption column.

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LEVELS AND SEASONAL VARIABILITY OF HEAVY METAL COMPOUNDS IN THE RIVERS OF THE CENTRAL CAUCASUS FOOTHILL ZONE

Posted in 2020, CHEMISTRY, Issue № 12(102) December 2020 | 0 comments

As part of environmental monitoring, the study conducts a situational analysis of water resources in the Kabardino-Balkarian Republic based on the data obtained in the period from 2005 to 2018. The study estimates the content and seasonal changes of heavy metal compounds in the water of the Terek, Malka, Baksan, Ardon, Cherek and Urukh rivers in the foothill zone of the Central Caucasus. The aim of the study is to assess the level of heavy metal compounds (Cr, Ni, Mo, Mn, Zn, Pb) in river water at six observation points located in the foothill zone of the Central Caucasus. The analysis was performed using the atomic absorption method using the electrothermal atomizer MGA-915M. The estimation of the level of heavy metal compounds in river water was performed according to such characteristics as the long-term average and median values of concentrations, the range of concentration fluctuations, and the rate of cases when the maximum permittable concentration according to the fishery standards (fishery MPC) is exceeded. Analysis of the multiannual data shows that most of the river water pollution with heavy metal compounds occurs during the summer rain flood and is of a natural origin, with the exception of the Baksan river. The table and graphs illustrate the detected levels of heavy metal compounds in river water during the studied period as well as the frequency of cases when the fishery MPC is exceeded.

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THE USE OF ACTIVE METHODS OF LEARNING THE LESSONS OF LIFE SAFETY

Posted in 2014, CHEMISTRY, Issue December 2014 | 0 comments

Active learning methods have in comparison with traditional methods numerous features. When using active learning methods in the course of life safety is necessary to allocate naimisharanya and simulation active learning methods, which determine, respectively, and view classes.

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MAKING THE COMPOSITE PLATE MATERIALS FROM THE SHELLS OF OAT

Posted in 2014, CHEMISTRY, Issue December 2014 | 0 comments

The article discusses the possibility of manufacturing the composite plate materials based on agricultural waste – shells oats.

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STARCH ESTERS SYNTHESIS WITH FATTY ACIDS DISENGAGED FROM SOAP STOCK

Posted in 2020, CHEMISTRY, Issue № 10(100) October 2020 | 0 comments

The paper discusses the regularities of obtaining starch esters with fatty acids of vegetable oils disengaged from oil extraction waste – soap stocks. The kinetics of starch acylation with fatty acids in the presence of thionyl chloride was studied in this work. The author considered kinetic regularities of the process of starch acylation with fatty acids occurring in the topochemical process with the Erofeev-Kolmogorov equation. The energy parameters were determined using the Eyring and Arrhenius equations based on the obtained values of the rate constants. The parameters of the transition complex formed during the acylation of starch with fatty acids are given as well. The formation of starch esters was confirmed by IR spectroscopy.

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DETERMINATION OF RESIDUAL QUANTITIES OF PHOSPHORIC HYDROGEN (PHOSPHINE) IN FRUIT VEGETABLES AND GREEN MASS OF PLANTS BY PHOTOMETRIC METHOD

Posted in 2020, CHEMISTRY, Issue № 10(100) October 2020 | 0 comments

The article presents the method for determining residual amounts of phosphine to control the safety of fruit and vegetable products and green mass of plants after their fumigation for the purpose of disinfection. The procedure includes processing the sample with dilute sulfuric acid, trapping the released phosphine with nitric acid, and subsequent spectrometric determination of total phosphorus with the help of ammonium molybdate and ascorbic acid as a reducing agent. The adapted method for the determination of phosphine in the objects under study can be used to control its residual amounts both in fruits and vegetables and green mass of plants, and in the treatment of flower crops in the fight against thrips, which is a quarantine object for the Russian Federation.

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STUDY OF OBTAINING STYRENE BUTADIENE-RUBBER FROM LATEX CUMULATIVE IMPACT OF A CATIONIC POLYELECTROLYTE AND MAGNETIC FIELDS

Posted in 2014, CHEMISTRY, Issue November 2014 | 0 comments

In this paper we studied the application magnetic field for allocation of styrene-butadiene rubber latex SKS-30 ARC in the presence of copolymer poly-N,N-dimethyl-N,N-diallilammony chloride to sulfur dioxide. Applications of this technology allows to reduce the consumption allocation coagulating agent

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DELIVERY LIGAND IN MICELLES IN THE DIRECT SYNTHESIS COMPLEX COMPOUNDS

Posted in 2014, CHEMISTRY, Issue October 2014 | 0 comments

The interaction of the copper surface with salitsilalanilinom in dimethylformamide. Delivery of a ligand to the surface of the copper -las carried in micelles of a nonionic surfactant surfactant. The critical micelle concentration of the surfactant in the dimethylformamide ( 15%).

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POLYMER NANOCOMPOSITE USED AS A STRUCTURAL MATERIAL FOR RAILWAY

Posted in 2014, CHEMISTRY, Issue October 2014 | 0 comments

The article describes how to prepare polymer compositions based on a thermoplastic polymer with nanoparticle inclusions of silica dioxide, how to identify important physico-chemical properties of the composition, and how to design the dowels structure of mounting assembly of rail fastening, based on proposed composite material.

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RESEARCH OF PROCESSES OF DETERMINATION OF GOLD CONTENT IN PRODUCTS OF GOK “NEVSKY “LLC ” DRUZA”

Posted in 2020, CHEMISTRY, Issue № 07(97) July 2020 | 0 comments

The article deals with the processes of determining the gold content in the products of the «Nevsky» mining and processing plant of«Druza» LLC. The activity of the assay and analytical laboratory to determine the content of gold in gold-containing products was investigated. The composition and structure of AAL GOK «Nevsky» LLC «Druza» is considered. The paper describes methods for determination of gold content in the products: atomic absorption method, titrimetrically method and Assay-gravimetric method. The principles of internal and external laboratory control in the AAL of a gold mining company are defined.

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SYNTHESIS OF HETEROCYCLIC COMPOUNDS IN COMBINATION OF 3- (4-METHYLPHENYLHYDRAZONO) -2,4-DIOXOPENTANE ACID WITH NH-MONONUCLEOPHILES

Posted in 2020, CHEMISTRY, Issue № 06(96) June 2020 | 0 comments

Claisen acylation of acetone with diethyl oxalate in the presence of sodium metal in toluene with further interaction with aryldiazonium chlorides taken in equimolar ratios in a neutral medium leads to the formation of ethyl esters of 3-arylhydrazono-2,4-dioxopentanoic acids.

Interaction of 3-arylhydrazono-2,4-dioxopentanoic acid ethyl ester with NH-mononucleophiles yielded new 1-aryl-5-hydroxy-4 – [(4-methylphenyl) hydrazono] -5-methylpyrrolidin-2,3,4-trions, their physicochemical characteristics are determined. The synthesized compounds are highly melting substances soluble in ordinary organic solvents, insoluble in water.

Structural features of the obtained compounds were established on the basis of mass spectrometry, IR, and NMR 1H spectroscopy. In the mass spectra of the isolated compounds recorded in the electrospray mode, signals of protonated and cationized molecules are observed. Signals of all proton-containing groups were detected in NMR 1H spectra, the formation of an intramolecular hydrogen bond with an oxygen atom of the OH group, or an oxygen atom in position 3 of the pyrrolidine ring is shown.

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SYNTHESIS, STRUCTURAL FEATURES AND BIOLOGICAL ACTIVITY OF BIS-(1-OXO-4-PHENYL-1-ETHOXYBUTANE-2,4-DIONATO)- AND BIS-(1-BUTOXY-5-METHYL-1-OXYHEXANE-2,4-DIONATO) METALS(II)

Posted in 2020, CHEMISTRY, Issue № 05(95) May 2020 | 0 comments

The development of new promising biologically active compounds is the topical direction of organic synthesis. By condensation of alkyl(aryl)methylketones with dialkyloxalates, sodium oxoenolates with alkyl and aryl substituents were synthesized in this work. bis-(1-oxo-4-phenyl-1-ethoxybutane-2,4-dionato)- and bis-(1-butoxy-5-methyl-1-oxohexane-2,4-dionato) metals (II) are isolated by metal exchange of sodium oxoenolyates with copper, zinc and nickel salts. The structure of the obtained metal complex compounds is confirmed by spectral analysis methods. The authors has established biological activity of some bis-(4-alkyl(aryl)-1-oxo-1-alkoxyalkane-2,4-dionato)metals (II) with respect to three types of test organisms: S. Aureus, E. Coli, P. Aeruginosa.

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POLYMER MATERIAL FOR PROTECTION AGAINST ELECTROMAGNETIC INTERFERENCE

Posted in 2014, CHEMISTRY, Issue June 2014 | 0 comments

In the work presents results of the development of radiation-protective material on the fluoroplastic base matrix that can be used in equipment of the spacecraft to reduce electromagnetic interference.

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A STUDY OF CHANGE OF TEMPERATURE COEFFICIENTS OF LINEAR EXPANSION OF POLYMER COMPOSITES

Posted in 2014, CHEMISTRY, Issue June 2014 | 0 comments

In the paper we study the dependence of the temperature coefficient of linear expansion of polymer composites on the content of filler.

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EFFECT OF VACUUM ULTRAVIOLET RADIATION ON HIGH-IMPACT POLYSTYRENE

Posted in 2014, CHEMISTRY, Issue June 2014 | 0 comments

In the work of the study of changes in the white shockproof polystyrene from the effects of vacuum ultraviolet light at room and elevated temperatures.

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RESEARCH OF CRYSTALLIZATION PROPERTIES AND GLASS STRUCTURE OF CONSTRUCTION PURPOSE BASED ON PRODUCTION WASTE

Posted in 2020, CHEMISTRY, Issue №2(92) February 2020 | 0 comments

Data on the synthesis of metastable glasses and glass crystalline materials based on the ash and slag of the Angren (CHP), flotation waste fluorite dressing factory (FOF) are summarized in this paper. The author shows the composition and technological parameters.

Such integrated processing of coal waste will not only ensure a significant expansion of the raw material base for the production of building materials and generate additional energy, but also help to solve environmental problems and improve the environmental situation in industrial regions.

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THE METHOD OF OBTAINING OF NANO-CRYSTALLINE POWDERS FOR EXAMPLE OF PbWO4

Posted in 2014, CHEMISTRY, Issue June 2014 | 0 comments

In this paper deals with an advanced method of obtaining ultradisperse powders of insoluble inorganic compounds by titration of the solution of one of the components of metabolic reactions solution of the other.

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THE MICROSTRUCTURE OF NANODISPERSED OF LEAD TUNGSTATE

Posted in 2014, CHEMISTRY, Issue June 2014 | 0 comments

In this paper deals the analysis micrograph nanodispersed lead tungstate obtained in the course of exchange reactions between Na2WO4 2H2O and Pb(CH3COO)2 times 3H2O.

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