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Vol. 4 Issue 1

Archives Journal Chemical Bulletin Vol. 4 Issue 1

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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THE USAGE OF VEGETABLE SORBENT FOR REMOVING CONGO RED DYE FROM TEST SOLUTIONS

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 44-55 p.
Abstract
The research findings of sorption purification of test water environment, containing Congo red dye, by using this crop farming waste as a sorption material have indicated that the maximum sorption capacity of its biomass amounts to 0.37 mmol/g. The electronic microscopy data and the research findings of physical-chemical and sorp-tion properties of a new vegetable sorption material, obtained from sunflower (Heliánthus ánnuus) stalks, are presented. The processing of the data demonstrated that the obtained adsorption isotherm of Congo red belongs to Type V isotherms according to classification by Brunauer-Deming-Deming-Teller (BDDT) or to the S-type, according to Giles’ classification. With that, adsorption process is the most accurately described by the Freundlich model, and the process proceeds on the heterogeneous surface of the sorption material.
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ADSORPTION OF 4-NITROPHENOL AND DYES ON SILVER-DOPED TiO2, TiO2-ZrO2, ZrO2 XEROGELS UNDER UV IRRADIATION

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 56-62 p.
Abstract
Nanoscale and composite materials containing titanium and zirconium oxides are of the greatest theoretical and practical interest. Their advantages are low cost, availability of production, the choice of source components and matrices of different nature. This work is an immersion in the subject of research at the Peoples' Friendship University of Russia. The research topic is extremely relevant, because silver appears only once in the list of previously used modifiers, and it is possible to study this issue. The production of TiO2 and ZrO2 nanopowders with dopants using gel technology is a simple and well-studied method for the synthesis of photocatalysts, but the effect of powder irradiation on adsorption has not been studied much, especially for irradiation of dry material with its subsequent introduction into an adsorption solution. It is of interest to study the effect on the adsorption of para-nitrophenol (the state of the molecule - anion or molecule), depending on the pH of the environment, on synthesized xerogels of titanium dioxide and zirconium. It is also necessary to conduct a study to understand the effect of silver on the adsorption of various types of dyes. Model dyes of the cationic type (methylene blue) and anionic type (methylorange) can be used to determine the charged surface centers of materials based on TiO2 and ZrO2 that do not contain or contain a dopant component.
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