344 research outputs found

    Stresses in the material with multilayered coating under impulse thermal loading

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    The two-dimensional model of mechanical behavior of the specimen with multi layered coating is formulated. The parametric analysis was carried out for various types of boundary conditions. Stress intensity depending on time was studied. The influence of impulse parameters on the temperature and stresses was investigated. It was revealed that radiation heat losses reduces the action of external loading

    Effect of organically bound iodine in cattle feed on health indicators

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    Currently, the problem of iodine deficiency is actual in the world, which may cause a large number of diseases and disorders. The problem of iodine deficiency for humans may be partly solved by enriching agricultural products with iodine, i.e. by providing animals with an increased intake of iodine during their growth. Theoretically, the most effective way to use iodine is the form bound to tyrosine, since diiodotyrosine has been proven to be a thyroxine precursor. Taking it into account, a supplement was developed containing iodine organically bound to tyrosine and histidine. In this work, we studied the effect of this supplement introduced into the diets of cattle on biochemical parameters of animal blood. In the test group, which received the supplement with organically bound iodine, an improvement in nitrogen metabolism was noted compared to the control group. This was most clearly demonstrated by the content of urea, since in the test group, its content decreased by β‰ˆ15 percentage points, and by the content of creatinine, since its increase in the test group was more than 20 percentage points. Differences in the parameters of carbohydrate and lipid metabolism between treatments were also noted, as in the blood of animals from the test group, the content of cholesterol, triglycerides, phospholipids, glucose and malondialdehyde was lower than in the control group. In mineral metabolism and morphological parameters, there was no significant difference between treatments. Among the indicators of pigment and hormone metabolism, it is important to note the reduced content of cortisol in the blood of animals from the test group. Its level was lower by β‰ˆ17.23 percentage points compared to the control group. A decrease in cortisol levels indicated a lower stress load in the test group. In general, studies have shown that the use of a feed supplement containing organically bound iodine has a positive effect on the metabolism of animals.Currently, the problem of iodine deficiency is actual in the world, which may cause a large number of diseases and disorders. The problem of iodine deficiency for humans may be partly solved by enriching agricultural products with iodine, i.e. by providing animals with an increased intake of iodine during their growth. Theoretically, the most effective way to use iodine is the form bound to tyrosine, since diiodotyrosine has been proven to be a thyroxine precursor. Taking it into account, a supplement was developed containing iodine organically bound to tyrosine and histidine. In this work, we studied the effect of this supplement introduced into the diets of cattle on biochemical parameters of animal blood. In the test group, which received the supplement with organically bound iodine, an improvement in nitrogen metabolism was noted compared to the control group. This was most clearly demonstrated by the content of urea, since in the test group, its content decreased by β‰ˆ15 percentage points, and by the content of creatinine, since its increase in the test group was more than 20 percentage points. Differences in the parameters of carbohydrate and lipid metabolism between treatments were also noted, as in the blood of animals from the test group, the content of cholesterol, triglycerides, phospholipids, glucose and malondialdehyde was lower than in the control group. In mineral metabolism and morphological parameters, there was no significant difference between treatments. Among the indicators of pigment and hormone metabolism, it is important to note the reduced content of cortisol in the blood of animals from the test group. Its level was lower by β‰ˆ17.23 percentage points compared to the control group. A decrease in cortisol levels indicated a lower stress load in the test group. In general, studies have shown that the use of a feed supplement containing organically bound iodine has a positive effect on the metabolism of animals

    Model of creation and management of the process of technological projects development

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    The purpose of the article is to determine and describe main principles and model of development of regional business accelerator on the basis of technical university for development of innovational startups. The research included the work on identification of the problems of the process of commercialization of technological developments, which business accelerator should solve. One of the basic purposes of creation of business accelerator is increase of the flow of prepared projects for consideration by investment committees of funds of early stages. Accelerator can be a full-scale unified mechanism of formation of deals flow from diversified mass of completed R&D. As a result of the research, the authors come to a conclusion that the process of creation of value and movement from prototype to entering a market supposes long chain with formation of various risks at each stage – scientific, financial, administrative, etc. Minimization of such risks requires from partners, involved with the work of business accelerator, solving emerging problems together. Such motivation could be formed by development of business accelerator by the principles of partnership and creation of equal access and rights for basic members.peer-reviewe

    FREQUENCY OF GENES POLYMORPHISM OF PRO-INFLAMMATORY CYTOKINES IN PATIENTS WITH CHRONIC ISCHEMIA OF CEREBRAL ISCHEMIA IN TRANSBAIKALIAN REGION

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    The results of research of occurrence of polymorphism of pro-inflammatory cytokines genotypes IL-1b (T-31C), IL-2(T330G), IL-6(C-174G), TNF(G-308A), IL-17A(G-197A), IL-17F (His-166Arg) in 195 patients with chronic cerebral ischemia are presented. The increase of frequency of a carriage of genotypes of IL-1Ξ²-31CC, IL-6-174GG, IL17A-197AA, IL17F-166ArgArg, alleles of IL-1Ξ²-31C, IL17F-166Arg is established (p < 0,05) in a clinical group

    Formation of the system of management of supporting university on the basis of strengthening of communication component

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    The article deals with changes in the system of management of educational establishments of higher education caused by creation of supporting universities. The program of creation of such universities supposes formation of universities-leaders in regions, which can consolidate educational and scientific basis for training of personnel in Russian subjects. During creation of supporting regional universities, the emphasis is made on the fact that they are to become the centers of innovational development, being a part of economy and region’s infrastructure at the same time. At that, creation of new engineering and implemental centers and R&D laboratories requires complex realization of projects for creation of high-tech production and necessary conditions for development of interface of regional supporting universities and enterprises. The article views functions and organizational structure of management of technical university; establishes dependence of intensity of organizational transformations on various factors. The authors show a process of formation of matrix organizational structure of technical supporting university with the use of mobile informational and communicational structures, which is formed by placement of horizontal connections on existing linear and functional structure.peer-reviewe

    The influence of brood chickens by-products processing with probiotic culture starter on change of their functional and technological parameters.

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    By-products are the potential source of animal protein obtained from brood chickens and egg-laying hens. Certain by-products like gizzards and combs are quite tough and possess low nutritional and biological value due to their high content of connective tissue. Biotechnological processing improves the quality parameters of collagen-containing by-products. In this article a probiotic starter culture of propionic acid bacteria, which have high proteolytic activity, was used to treat the gizzards and combs of brood chickens. Before processing of by-products with starter culture, physical and chemical parameters and the yield of by-products in relation to poultry live weight were analyzed and recorded. 5%, 10% and 15% starter culture were added to the tested samples of chopped by-products, the samples were kept at a temperature of 30 Β°C, and every 4 hours the following functional and technological parameters were monitored: moisture binding capacity, water holding capacity (MBC and WHC) and yield of the product after heat treatment. The results proved that increase of starter culture amount and longer exposure of by-products to hydrolysis led to decrease of functional and technological parameters values, but for the combs those parameters remained at a sufficiently high level compared to the gizzards, as the gizzards were exposed to more intense hydrolysis than combs. The decrease in the pH value correlated with the dynamics of MBC and WHC changes; and dynamics of the product yield after the heat treatment. Also the stained histological preparations were studied in order to assess the influence of biotechnological processing on by-products microstructure, where significant differences were found in the morphological structure of muscle and collagen fibers of hydrolysates of combs and gizzards exposed to action of bacterial concentrate. The results of rheological studies showed that hydrolyzed chicken combs differed from gizzards; the combs were denser and featured more elastic structure due to a lower degree of hydrolysis by bacterial enzymes. In general, the properties of collagen-containing by-products (muscular gizzards and combs) change significantly after being exposed to enzymes of propionic acid bacteria

    Scale effects in tribological properties of solid-lubricating composites made of ultra-high molecular weight polyethylene filled with calcium stearate particles

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    Friction properties being influenced by scale effects are simulated in the paper by the example of polymer composite material made from Ultra High-Molecular Weight Polyethylenes (UHMWPE) filled by calcium stearate (C[36]H[70]CaO[4]). Of interest are the composites whose mechanical properties and tribotechnical characteristics do not depend monotonically on filler (inclusions) weight fraction. In order to describe the influence of scale effects onto frictional properties the model based on Reiss averaging (model of "weak phase") is employed. It is also suggested that when gradient elasticity theory is applicable the formal analogy between effective friction coefficient for surface heterogeneous structures and effective mechanical properties (compliances) for heterogeneous material can take place. Theoretical dependence to describe nonmonotonic change of effective friction coefficient versus filler concentration was obtained for the polymer composites under study. The suggested expressions might be useful for the sake of properties prognosis of antifriction polymeric materilas

    Novel D-A-Ο€-A1 Type Organic Sensitizers from 4,7-Dibromobenzo[d][1,2,3]thiadiazole and Indoline Donors for Dye-Sensitized Solar Cells

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    Two novel D-A-Ο€-A1 metal-free organic dyes of the KEA series containing benzo[d][1,2,3]thiadiazole (isoBT) internal acceptor, indoline donors fused with cyclopentane or cyclohexane rings (D), a thiophene as a Ο€-spacer, and a cyanoacrylate as an anchor part were synthesized. Monoarylation of 4,7-dibromobenzo[d][1,2,3]thiadiazole by Suzuki-Miyamura cross-coupling reaction showed that in the case of indoline and carbazole donors, the reaction was non-selective, i.e., two monosubstituted derivatives were isolated in each case, whereas only one mono-isomer was formed with phenyl- and 2-thienylboronic acids. This was explained by the fact that heterocyclic indoline and carbazole fragments are much stronger donor groups compared to thiophene and benzene, as confirmed by cyclic voltammetry measurements and calculation of HOMO energies of indoline, carbazole, thiophene and benzene molecules. The structure of monoaryl(hetaryl) derivatives was strictly proven by NMR spectroscopy and X-ray diffraction. The optical and photovoltaic properties observed for the KEA dyes showed that these compounds are promising for the creation of solar cells. A comparison with symmetrical benzo[c][1,2,3]thiadiazole dyes WS-2 and MAX114 showed that the asymmetric nature of benzo[d][1,2,3]thiadiazole KEA dyes leads to a hypsochromic shift of the ICT band in comparison with the corresponding benzo[c][1,2,5]thiadiazole isomers. KEA dyes have a narrow HOMO-LUMO gap of 1.5–1.6 eV. Amongst these dyes, KEA321 recorded the best power efficiency (PCE), i.e., 5.17%, which is superior to the corresponding symmetrical benzo[c][1,2,3]thiadiazole dyes WS-2 and MAX114 (5.07 and 4.90%)
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