14 research outputs found

    Study of Hybrid Modification with Humic Acids of Environmentally Safe Biodegradable Hydrogel Films Based on Hydroxypropyl Methylcellulose

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    The possibility of increasing the complexity of the operational properties of environmentally safe biodegradable polymer hydrogel materials based on hydroxypropyl methylcellulose due to modification by humic acids from lignite is considered. As a result of this research, environmentally safe hybrid hydrogel films with antibacterial properties were received. In the framework of physicochemical studies, it was determined by IR spectroscopy that hydroxypropyl methylcellulose modified with humic acids hybridmaterials are received by the mechanism of matrix synthesis, which is accompanied by hydroxypropyl methylcellulose crosslinking through multipoint interaction with the carboxyl group of humic acids. Regularities in terms of changes in water absorption, gelation time, and mold emergence time regarding the environmentally safe biodegradable polymer hydrogel materials based on hydroxypropyl methylcellulose depending on the humic acid content were revealed. It was established that the optimal humic acid content in environmentally safe biodegradable hydrogel films with bactericidal properties based on hydroxypropyl methylcellulose is 15% by mass. It was also established that the hybrid modification of hydroxypropyl methylcellulose with humic acids allows them to preserve their biodegradation properties while giving them antibacterial properties. The environmentally safe biodegradable hydrogel films with bactericidal properties based on hydroxypropyl methylcellulose and humic acids are superior in their operational characteristics to known similar biodegradable hydrogel films based on natural biopolymers

    Study of lignite humic acids hybrid modification technology of biodegradable films based on polyvinyl alcohol

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    Object of article study is lignite humic acids hybrid modification technology of biodegradable films based on polyvinyl alcohol. The possibility of increasing the strength and operational properties of biodegradable polymeric materials based on polyvinyl alcohol by using its modification with the different types of humic acids from lignite is considered. Lignite humic acids hybrid modification films with antibacterial properties were obtained. The two-stage technology of lignite humic acids hybrid modification of biodegradable films based on polyvinyl alcohol was formalized. At the first stage of lignite humic acids hybrid modification technologies for hybrid-modified biodegradable materials production, lignite humic acids are received. At the second stage, hybrid modification of lignite humic acids (that are part of biodegradable polyvinyl alcohol films), which are received by watering from a solution, takes place. It has been conducted a study on determining the effect of lignite humic acids hybrid modification on the most important operational properties of biodegradable film based on polyvinyl alcohol, i. e., tensile strength, relative elongation at break and time of mold appearance. Changes in tensile strength, relative elongation at break and time of mold appearance for the lignite humic acids hybrid modified biodegradable polymeric materials based on polyvinyl alcohol were revealed depending on the content of the different types of lignite humic acids. It was also shown that the lignite humic acids hybrid modification of polyvinyl alcohol with the different types of humic acids allows preserving the biodegradability of the films along with imparting the antibacterial properties. The developed lignite humic acids hybrid modified biodegradable polyvinyl alcohol films with antibacterial properties, in terms of their operational characteristics, are superior to the known similar biodegradable films based on natural biopolymers

    Factors Affecting the Formation the Carbon Structure of Coke and the Method of Stabilizing Its Physical and Mechanical Properties

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    The raw materials (coals different stages of metamorphism) and technological factors (period and temperature) of the coke-making that determine the carbon structure of blast furnace coke, and its physical and mechanical properties are analyzed. The change granulometric composition of the coke as a function of the coal batch properties is described in detail. The installation determines the possibility of influencing the carbon structure of coke, its granulometric composition in its production in order to increase the yields of the most valuable fractions, and improving its quality characteristics to achieve high-performance blast furnaces. Analysis of the results indicates that, with no changes in the coking conditions, the granulometric composition depends significantly on the ash content and packing density of the coal batch. Research has shown that the petrographic composition of the coal batch also affects the structure and size of the coke. The closest relationship is established between the magnitude of the fusinized components ΣFC and the output of the coke fractions 80–60 mm, 40–25 mm, and M25, M10, and class >80 mm in continuous or periodically working open or closed industrial cylindrical oblique stabilizer drum

    Lignite oxidative desulphurization: notice 3—process technological aspects and application of products

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    Abstract The study reviews the process of oxidative desulphurization of high-sulphur Ukrainian lignite, which was performed by coal treatment using an air or air–steam mixture. In the process, sulphur-free fuel and tar from the decomposition of coal organic matter was obtained. Hence, the sulphur in the coal was converted into hydrogen sulphide. The coal desulphurization process is critical to power generation, power generation and technology, and technology field of application. The coal desulphurization process ensures the maximum recovery of the highest content of sulphur and hydrogen sulphide (H2S) in desulphurized gases at minimal energy costs. The process also enhances the maximum decomposition of tar and sulphur recovery (> 50%) during coal power generation. Based on summarized field studies, a block schematic diagram coupled with heat and material balances of the process was developed for the calculations. The application of the technology at the first stage of coal combustion in thermal power plants will enable the utilization of over 50% of recovered coal sulphur in the form of concentrated H2S or commercial elemental sulphur. This will, nevertheless, allow for a reduction of sulphur oxide pollution in the environment by at least 53%–56%. It has been suggested that the product of thermal decomposition of coal organic matter (tar) can be used as a component of furnace fuel oil or as a plasticizer of petroleum-based road bitumen

    Effect of hydrodynamic parameters on the oxidative desulphurisation of low rank coal

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    Abstract In this paper, the desulphurisation of high sulphur low-rank coal is proposed as a raw material for pulverised coal injection technology. Therefore, the influence of oxidant linear velocity and the size of the coal grain was investigated in a fluidised bed. The hydrodynamic parameters of the fluidised bed including: porosity, Sherwood criterion (diffusion Nusselt number), and mass transfer coefficient (external surface) were calculated. Furthermore, the study examined the effects of intensity and efficiency on the desulphurised coal properties; organic matter, ash, and volatile matter contents. The key changes during the conversion of pyritic sulphur and coal organic matter were subsequently examined. The results showed that the sulphur content (S t d 3.16 wt%) of the low-rank coal, was transformed to (S t d  ≤ 1.5 wt%) after desulfurization. Other enhanced properties were: V daf ≤ 38.0 wt%; A d ≤ 10.0 wt%, now suitable for pulverised coal injection technology

    Application efficiency of complex pharmacotherapy schemes at combined mycotoxicosis in young bulls

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    The article presents data on the study of the effectiveness of tetra-p feed additive and toxin adsorbents Minazel plus and Sorbitox introduced into feed, naturally contaminated with mycotoxins. The experiment was conducted on young bulls of 9 months age, which for 3 months got the preparations in diets in the following concentrations: the first group – tetra-p – 5.0 kg/t of feed, Minazel plus – 1.5 kg/t of feed, the second group – tetra-p – 5.0 kg/t of feed, Sorbitox (1.5 kg/t of feed). The results of the experiment determined that the use of tetra-p in combination with preparations with sorption activity had a pronounced therapeutic effect on the body of young bulls. An improvement in the clinical condition of animals was observed from 14-16 days of the experimental period and was manifested by an increase in appetite, normalization of the gastrointestinal tract, as well as by an increase in body weight gain by 11.7 % and 10.3 %. Blood biochemical parameters were characterized by an increase in the level of total protein by 12.4–15.8 % (p ≤ 0.01), albumin by 18.0–21.3 %, urea by a factor of 1.53–1.44 (p ≥ 0.01), cholesterol by 1.4–1.56 times and triglycerides by 1.6 times. The activity of liver enzymes decreased by 18.3–21.4 % (ALT) and by 25.7–27.1 % (AST). It has been proved that the developed scheme improves the effectiveness of treatment of mycotoxicosis in animals by the optimizing effect on metabolism, restoration of impaired homeostasis, activation of reparative processes of the liver tissue and increased deposition, activation and utilization of pollutants, produced by microscopic fungi

    Study of Hybrid Modification with Humic Acids of Environmentally Safe Biodegradable Hydrogel Films Based on Hydroxypropyl Methylcellulose

    No full text
    The possibility of increasing the complexity of the operational properties of environmentally safe biodegradable polymer hydrogel materials based on hydroxypropyl methylcellulose due to modification by humic acids from lignite is considered. As a result of this research, environmentally safe hybrid hydrogel films with antibacterial properties were received. In the framework of physicochemical studies, it was determined by IR spectroscopy that hydroxypropyl methylcellulose modified with humic acids hybridmaterials are received by the mechanism of matrix synthesis, which is accompanied by hydroxypropyl methylcellulose crosslinking through multipoint interaction with the carboxyl group of humic acids. Regularities in terms of changes in water absorption, gelation time, and mold emergence time regarding the environmentally safe biodegradable polymer hydrogel materials based on hydroxypropyl methylcellulose depending on the humic acid content were revealed. It was established that the optimal humic acid content in environmentally safe biodegradable hydrogel films with bactericidal properties based on hydroxypropyl methylcellulose is 15% by mass. It was also established that the hybrid modification of hydroxypropyl methylcellulose with humic acids allows them to preserve their biodegradation properties while giving them antibacterial properties. The environmentally safe biodegradable hydrogel films with bactericidal properties based on hydroxypropyl methylcellulose and humic acids are superior in their operational characteristics to known similar biodegradable hydrogel films based on natural biopolymers

    As redes de solidariedade da cor: o caso dos compadres Manoel e Lauriano The Colour Solidarity Networks: the case of the 'compadres' Manoel and Laurino

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    O artigo baseia-se na analise de um processo criminal de 1831, no qual os réus, pardos, são acusados de assassinar um homem branco. No teor dos depoimentos revela-se a formação de uma aliança solidária dos pardos, em função das categorias que definem as posições e juízos a respeito do crime. Testemunhas pardas e crioulas, livres e forras, produzem um consenso construindo uma versão contra a vítima, o homem branco. Uma visão sobre o certo e o errado solidariza a todos e, dentro dela, uma percepção específica da justiça une pardos, crioulos e cabras. Propõe-se que a solidariedade com base na identidade entre "pardos" possa ter tido uma intencionalidade e motivações associadas aos debates políticos da época, travados entre liberais moderados e conservadores, a respeito da conceituação e inclusão dos ‘pardos’ no projeto de nação. Representa uma tentativa de se captar, nos indícios disponíveis, a formação de processos identitários com base na cor e na condição, categorias ordenadoras fundamentais da sociedade escravista.<br>This article is based on the analysis of a criminal lawsuit from 1831, in which the accused ones, who were "mulattos", were charged with a white man murder. In the testimonies of the lawsuit, it is possible to identify a supportive alliance among the "mulattos", in relation to the categories that define the positions and judgements concerning to the crime. Witnesses, both "mulattos" and "negros", free and manumitted slaves, have produced a consensus, hence building a version against the victim, the white man. A view on right and wrong promotes solidarity in everybody and, within this view, a specific perception about what unites "mulattos", "negros", manumitted slaves and "cabras". We propose that the solidarity based on the identity among the "mulattos" can be understood in relation to the motivations associated to their emersion in the political debates of the time, concerning to their conceptualization and inclusion in the nation project. This article represents an attempt to understand, in the available indexes, the constitution of identity processes based on color and condition, fundamental categories in the slave society
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