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2021

Archives Journal Chemical Bulletin Vol. 4

PROSPECTS FOR THE USE OF SOSNOVSKY HOGWEED PROCESSING PRODUCTS IN CHEMICAL TECHNOLOGY

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 7-16 p.
Abstract
It is shown that restrictions on the spread of the invasive and dangerous for humans plant of Sosnovsky hogweed are carried out as needed. One of the restrictions on the spread of this plant can be the processing of Sosnovsky hogweed using chemical technology. It was determined that the optimal conditions from the standpoint of chemical technology are the processing of the fruits of this plant of waxy ripeness. Extraction processing of the fruits of wax ripeness with petroleum ether in a Soxhlet apparatus made it possible to obtain 2.9% of the mass. essential oil, which, according to chromatographic analysis using a gas chromatograph equipped with a flame ionization detector, an electronic integrator Crystallux 4000M, contained 56% of the mass. esters. The work shows that the essential oil in the composition of the compound with vaseline oil in a ratio of 1: 1 by volume can be used not only as a softener in the formulation of rubber compounds based on light crepe, but also as a plasticizer, imparting increased frost resistance to technical rubbers. With practically the same elastic strength characteristics of rubbers under tension with industrial oil I-12A and with essential oil, the increased frost resistance of rubbers with essential oil will allow them to be utilized into crumb rubber for the production of polymer-bitumen binders that reduce cracking of road surfaces.
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STUDY OF AGGREGATIVE STABILITY OF LIPID CONCENTRATE PRODUCTION MODEL WASTE WATER AND POSSIBILITY OF ITS PURIFICATION BY SORPTION METHOD

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 17-28 p.
Abstract
In the Belgorod region, work is underway to create the first high-tech large-scale production of lipid concentrate and animal protein from the larvae of the Black Soldier fly Hermetia illucens in Russia. The lipid concentrate emulsifies well in tap water, which indicates the presence of substances in it that do not belong to triglycerides of fatty acids. Obviously, it contains impurities of compounds present in the larval biomass - protein compounds and their decay products, phospholipids, etc., which can play the role of surfactants. This paper presents the results of studies on the possibility of fat-containing wastewater purification using a sorption material obtained by leaf litter of the horse chestnut genus (Aésculus hippocastanum L.) carbonization. It was found that the lipid concentrate is easily emulsified, both in pure form and in the presence of sodium lauryl sulfate. The resulting emulsions are highly resistant to degradation. It was found that the presence of the surfactant in an amount of 0.01 g/l improves the purification efficiency in the process of the model emulsion adsorption treatment. The addition of 0.6 g of the material allows to reach 92% purification, and with the addition of 1.5 g the efficiency is 98%. Similar amounts of sorbent in a pure emulsion make it possible to achieve values of only 35% and 88%, respectively. When finely dispersed particles of inorganic substances are added to an aqueous medium, the suspension effect is often observed, which manifests itself in the difference between the pH values of the suspension and the filtrate. The results of studies of the amount of added sorbent effect on pH changes in suspensions and filtrates showed that the complex «lipid micelle + sorbent» has a positive charge, and in the presence of the surfactant the charge retains a positive value, but is very close to neutral. An approach to the isoelectric point is observed.
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PALLADIUM NANOELECTROCATALYSTS ON COMBINED MATRIX-SUPPORTS FOR CHEMICAL POWER SOURCES

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 29-36 p.
Abstract
Fuel cells with direct oxidation of formic acid are promising converters of chemical reaction energy into electricity due to the high open-circuit potential, safe (non-flammable and non-toxic) fuel and higher energy characteristics compared to chemical current sources with direct oxidation of alcohols. The crossover effect with a low formic acid content allows the thin membrane application, as well as a high concentration of fuel (up to 20 M), which helps to increase the structure specific power parameters as a whole. Catalysts based on Pt or Pd are widely used in the electrooxidation reaction of formic acid. It has been known that catalysts based Pd are more effective than that Pt due to their resistance to carbon monoxide as the main reaction product. In this paper, the volt-ampere and watt-ampere characteristics of formic acid-based fuel cells and air under model operating conditions were studied. The tests were carried out on a certified laboratory stand of a fuel cell, to which a working model of the investigated membrane-electrode unit was connected. The optimal characteristics of the catalyst loading are established to achieve optimal parameters of current density and specific power. The creation of new catalysts and the modification of existing ones will help to increase the electrodes operation time, reduce the production cost, in-crease their efficiency by increasing efficiency, and also use as fuel not only hydrogen, but also other fuels such as formic acid.
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MODELING OF COMPLEX OF DENDRIMER WITH PEPTIDE

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 37-47 p.
Abstract
Biocompatible branched polymers can be used in many biomedical applications, including drug and gene delivery. In previous articles, we applied a computational approach to study complexes of positively charged lysine branched polymers and their complexes with some negatively charged regulatory oligopeptides. The goal of this article is to test the possibility of complex formation between peptide dendrimer and therapeutic oligopeptide molecules. A system consisting of one dendrimer, 16 oligopeptide molecules and counterions in water was studied by the molecular dynamics method. For this purpose, the Gromacs molecular modeling software package and the Amber force field were used. First of all, the process of complexation was studied and it was shown that negatively charged oligopeptide molecules are attracted by the dendrimer and quickly form a stable complex with it. After reaching a plateau of all characteristics of the complex, its average equilibrium dimensions, shape anisotropy, and internal structure were calculated. They turned out to be similar to the characteristics of the complexes formed by other branched lysine molecules with similar molecular weights and charges.
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SORPTION PROPERTIES OF BLACK SOLDIER FLY (HERMETIA ILLUCENS) MAGGOTS VERMICULTURING ZOOCOMPOST TO «METHYL ORANGE» DYE

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 48-57 p.
Abstract
The paper considers the issues, concerned with possible release as part of sewage waters of an organo-mineral pollutant ‒ methyl orange dye – to the environment. This dye has become widely used in textile industry, food industry, and in building materials production. High concentrations of this dyestuff are toxic and can cause damage to skin and eyes. Getting into the body system, the dye can form even more toxic aromatic amines in course of metabolic processes. The toxic effect can occur even at 5% concentration of the dye.
To reduce the toxic influence of wastewaters, containing dyestuffs such as methyl orange, various purification methods are used, including sorption. To increase the cost-effectiveness of the process, the sorbents, based of various industrial wastes, have found application lately. In the present research the material, based on black soldier fly (Hermetia Illucens) maggots’ vermiculture, was used.
According to experimental findings and the adsorption isotherm, the type of the sorption material’s pores and the type of sorption were determined. It has been demonstrated that the sorption material belongs to transition-porous sorbents, which is essential for extracting large molecules of the dye. According to the isotherm, the dye molecules sorption proceeds in stages: at first, a monolayer is formed, which is indicated by the first plateau in the isotherm. At the second stage, a multilayer in the form of dye molecules’ chains or clusters – the second plateau in the isotherm – is formed. The sorption mechanism is predetermined by the specific composition of zoocompost particles. Zoocompost is rich in humic compounds with such functional groups as ‒NH, ‒OH, ‒C=O. The presence of these groups makes it possible to adsorb anionic dyes, including methyl orange dye, due to electrostatic interactions or hydrogen bonding.
The influence of the sorbent’s weight, particles size, reaction mix temperature, duration of sorption process on methyl orange dye removal degree was studied. The sufficient efficiency of the process up to 90% was demonstrated.
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PHYSICO-CHEMICAL FEATURES OF THE PALLADIUM NANOCATALYSTS FORMATION ON COMBINED MATRICES-CARRIER FOR FUEL CELLS

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 58-66 p.
Abstract
The development of modern nanotechnological methods and approaches to the synthesis and formation of nanostructures allows us to create new materials that combine various functional properties and unique physical and chemical characteristics. Such structures include composite materials consisting of a structured matrix modified with various fillers. Currently, composites are of particular interest to researchers, in which nanoscale particles play the role of filler, which makes it possible to obtain catalysts with increased activity and stability. Commercial perfluorinated proton exchange membranes of the Nafion type and carbon-containing carriers (carbon nanotubes, graphene, fullerenes) are promising carrier matrices for chemical energy sources – fuel cells. Nanoparticles based on platinum, palladium, or their alloys are excellent materials for the reactions of electrocatalytic oxidation of hydrogen and oxygen reduction that occur in fuel cells. The elements based on the direct oxidation of formic acid mainly use bimetallic nanoparticles based on palladium, which exhibit higher catalytic properties. In this work, new effective polymer-carbon composites modified with palladium nanoparticles were synthesized. Single- and multi-wall carbon nanotubes were chosen as substrates. Physicochemical studies of the obtained materials were carried out using electron microscopy and small-angle X-ray light scattering. The sizes of nanoparticles in the composition of functional carrier matrices are determined. It was found that the carbon filler contributes to the better stabilization of small nanoparticles in the composition of the composite. The data on the influence of the conditions for the formation of metal nanoparticles on their size, shape and distribution over the matrix surface are obtained. The stability of samples with variable palladium loading on various carrier matrices was studied by chronoamperometry. The prospects of using the formed materials for fuel cell electrodes with direct oxidation of formic acid are proved.
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EXPERIENCE IN CREATING LAYERED RADIATION- PROTECTIVE MATERIALS ON A TEXTILE BASIS

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 7-16 p.
Abstract
The technology of creating radiation-protective lead materials on a textile basis was developed. A method of electrochemical deposition of lead on a metallized fabric from a hydrogen borofluoride electrolyte was developed. The influence of the increase in the caliber of the lead electrochemical coating on the changes in the density of the mesh and the living cross-section of the metallized fabric is determined. The efficiency of the radiation-protective properties of the material is estimated by determining the linear attenuation coefficient of gamma quanta with an energy of 0.662 MeV from the Сs-137 source using a scintillation single-channel gamma spectrometer. It is noted that due to the spatial arrangement of the layers of metallized fabric with an optimal range of lead-coated calibers from 75 to 100 micrometers, having a live cross-section of no more than 0.05%, an abnormally strong change in the intensity of penetrating radiation occurs. It is shown that when duplicating a metallized fabric with a lead coating, the living cross-section of the duplicated structure is a power function of the number of layers of the metallized fabric. It is noted that the metallized fabric with a lead coating in the studied range of calibers has a multiplicity of attenuation of gamma-radiation Cs137 below the lead plate of a similar caliber.
In the resulting radiation-protective material on a textile basis, both traditional technological approaches are implemented - the use of lead, and innovative ones associated with the use of multilayer materials to implement an abnormally strong change in the intensity of penetrating radiation.
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DETERMINATION OF THE ALKALINITY OF WATER WITH HIGH SALINITY: USING THE TITRATION FUNCTION

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 17-24 p.
Abstract
Measurements of parameters expressed in terms of carbonic species, such as alkalinity and acidity of saline waters, do not analyse the influence of external titration parameters such as total free and bound carbonic species concentration, activity ratio, ion pair formation and residual liquid coupling potential in pH measurements. This paper shows the development of an F5BC titration function based on the titration developed by Grahn (1952) for the carbonate system of natural waters. For practical use, saline water samples from the Pocinhos Reservoir in Paraíba were titrated and linear regression analysis was performed. The results showed that F5BC implies the determination of the Grana functions F1x and F2x, respectively, for alkalinity and acidity calculations without knowing "a priori" the titration endpoint. F5BC also allows the determination of the first and second apparent dissociation constants of the carbonate system of saline and high ionic waters.
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CHEMICAL-TECHNOLOGICAL PROCESSES OF SEPARATION OF MILK WHEY FOR ITS USE IN COSMETOLOGY

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 25-38 p.
Abstract
The article is devoted to the analysis of chemical and technological processes of production and processing of whey for the purposes of its use in cosmetology. The author indicates the relevance and significance of the research topic. The composition of whey is considered. Attention is focused on the fact that the components contained in it are raw materials for various cosmetics, in particular, shampoos. A comparative analysis of traditional and non-traditional methods of processing whey is carried out. The conclusion is made in favor of the latter and the thesis is argued that the promising technology for processing and further concentration of whey is precisely the membrane technology, which allows the processes to be carried out under sparing temperature conditions, without a phase transition and, accordingly, at the lowest energy costs. The use of membrane technologies leads to a reduction in the capital and operating costs of the enterprise, which, in turn, reduces the payback period of the equipment.
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MICROBIOLOGICAL ANALYSIS OF YEAST AND “YEAST-FREE” BREAD

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 39-43 p.
Abstract
The article is devoted to the problem of the usefulness of yeast and yeast-free bread. The authors substantiate the relevance and expediency of the topic of study. Comparative analysis of two methods of preparing rye simple bread was carried out by microbiological analysis of starter, recognition of microorganisms was carried out on the basis of atlases. A comparative study of bread preparation technologies by traditional and industrial methods is also presented. As a result, the authors come to the following conclusions: firstly, the "childless" starter for home baking, is a spontaneous fermentation product containing "wild" yeast, while the industrial contains only lactobacteria, baker's yeast and minimal admixture of other microorganisms; secondly, the ratio of lactobacteria to yeast in the industrial starter is optimal, and in the home it is not observed, which can affect both fermentation conditions and the growth of another microflora; thirdly, the number of colony-forming units, as well as bacteria of the E. coli group in industrial baking bread is strictly regulated by GOST and regularly checked, and in the home starter Enterobacter is sufficiently present, and its amount in baked bread is unknown. In summary it is concluded that "yeast" and "yeast-free" bread are useful.
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