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  • Improvement of sedimentation efficiency in the technology of heavy metal leaching from galvanic sludge

    The paper presents the results of experimental studies on increasing the settling rate and reducing the solid phase in the clarified layer during settling of a solution of sulfuric acid leaching of heavy metals from galvanic sludge. For this purpose, it is proposed to use a monoethanolamine vinyl ester copolymer with sodium or potassium methacrylate as a flocculant. This flocculant works well in a wide range of pH of the solution medium, unlike the well-known and widely used polyacrylamide flocculant. The increase in the efficiency of settling is achieved due to the fact that the flocculant in question makes it possible to simultaneously flocculate positively and negatively charged particles due to the presence of various functional groups in its composition. The use of the proposed flocculant will ensure a more complete extraction of heavy metals from galvanic sludge, which reduces the risk of environmental pollution and their reuse in industry.

    Keywords: galvanic sludge, heavy metals, leaching, flocculant, settling, suspended solids

  • Mediator-assisted selective oxidation of 5-hydroxymethylfurfural to 2.5-diformylfuran in the presence of collidine

    The process of 4-acetylamino-2,2,6,6-tetramethylpiperidine-1-oxyl/I2 mediated oxidation of 5-hydroxylmethylfurfural in a twophase system consisting of a methylene chloride and aqueous solution containing sodium hydrogen carbonate was investigated. It was shown that the introduction into the reaction system collidine provides selective oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran (yield 99% at a selectivity of 100%).The optimal composition of the system and the optimal conditions of synthesis were determined. A mechanism of promoting the oxidation of the OH- group of 5-hydroxymethylfurfural and protecting the further oxidation of 2,5-diformylfuran by collidine was proposed.

    Keywords: 5-hydroxymethylfurfural, 2,5-diformylfuran, nitroxyl radical, collidine

  • Wear resistance of the carbon electrical material by modifying novolac binder

    Prospects for manufacturing electrical investigated products based on modified copper oxide (I) a novolac resin. It is shown that copper oxide modification improves the physico-mechanical, tribological, electrical properties, resistance to mechanical wear and oxidation products of the materials. Introduction of coke in the material increases its durability when operating on the worn contact network. Trial runs have shown a trolley parks that the contact insertion trolley manufactured using a modified copper oxide (I) novolak binder in performance on average 2-4 times higher than the commercial materials of different manufacturers

    Keywords: trolley collector insert, carbon and graphite material, modification of the novolak binder, copper oxide (I), sea trials

  • Joint-stock insurance business on the Don in the second half of XIX - early XX centuries

    History share of insurance business in the Province of the Don, the characteristic four stages of development process, the analysis in general and the specific activity of sixteen joint campaigns, including foreign, on the Don in the late XIX - early XX centuries. ("New York", "Urbain", "Ekvitebl"). The social composition of the policyholders, insurance forms discounts logic of competition  

    Keywords: insurance organization of insurance business corporate insurance insured event insurance discount insurance premium insurance rates insurance capital

  • Study of corrosion and electrochemical properties of anode coatings oxide for production dilute sodium hypochlorite

    Consider the choice of coating anodes for electrolysis of sodium hypochlorite nizkokontsentrovannogo 3% solution of sodium salt of food and water of the Black Sea. Defined corrosion resistance of anodes with different laying oxides of ruthenium and iridium and their characteristics: yield chlorine-current voltage on the cell growth dynamics of the concentration of active chlorine in the solution.

    Keywords: oxide coatings, iridium, ruthenium, low concentration of sodium hypochlorite, the corrosion resistance of anodes according to the output current of chlorine, the electrolysis of a 3% solution of sodium edible salt and sea water.

  • Local Atomic and Electronic Structure of the Fe dopants in AlN:Fe Nanorods

    Fe-doped AlN nanorods were studied by means of x-ray absorption spectroscopy above the Fe K- and L2,3- edges. Theoretical simulations of the x-ray absorption spectra show that Fe atoms mainly substitute Al. A minor fraction of Fe interstitials or Fe-Al-N ternary alloy can be identified as well. Bader’s AIM analysis predicts that neutral substitutional FeAl defect is in 2+ charge state, though Al in pure AlN is in 3+ charge state.  Fe L2,3 absorption spectra and photoluminescence data indicate the coexistence of Fe2+/Fe3+ in AlN:Fe nanorods so different charge states of substitutional FeAl should co-exist.

    Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production

  • Local atomic and electronic structure of nanostructured condensed materials for rechargeable current sources on the basis of V2O5/Fe/LiF nanocomposite within charge-discharge cycle

    In this paper we study of the local atomic and electronic structure of nanostructured condensed material for rechargeable current sources on the basis of 15mas.%V2O5/Fe/LiF nanocomposite within charge-discharge cycle. Principle component analysis (PCA) of the series of Fe K-edge spectra collected during 1 st charge showing the concentrations of the components Fe, FeF2 and V[FeV]O4. We found the changes in the V oxidation state from the analysis of the experimental Fe K- and V K- XANES spectra. Total and partial density of states of components are presented.

    Keywords: nanostructured materials for rechargeable current sources, dynamics of local atomic and electronic structures, XANES, DFT

  • Comparative study of the catalytic activity Pt/C and PtхNi/C materials in the oxygen electroreduction

    The catalytic activity of Pt/C and PtxNi/C electrocatalysts prepared by  borohydride methode was studed. It was established that the specific activity  of fresh prepared Pt3,7Ni/C  catalyst  in oxygen  electroreduction  reaction is higher in compare with Pt/C material. After treatment of Pt3,7Ni/C material in the hot acid  nickel in the surface layers of nanoparticles was dissolved and the composition of nanoparticles was changed to Pt5,6Ni. The electrochemical surface area of the Pt5,6Ni catalyst and specific activity was slightly decreased after corrosion treatment. 

    Keywords: platinum electrocatalysts, corrosion stability of the nanoparticles, fuel cells, X-ray diffraction, borohydride synthesis

  • Development of elements for "smart clothes" based on the electrochemical charge storage system for microsystems technique

    In this paper we propose basic geometric, mass and electrical parameters of the element for collection of static electricity from the surface of the textile. This element is a reversible electrochemical charge storage system based on nanostructured nickel oxide and carbon cloth. Element has a planar structure, it is flexible, lightweight, safety and ergonomic. Proposed element can be used as a power source for the Microsystems technique in "smart clothes".

    Keywords: "smart clothes", microsystems technique, static electricity, supercapacitor, composite material NiO/C

  • Local Atomic Structure and Computer Modeling of the Copper Ion in Amyloid Beta Peptide: XAS Study

    Alzheimer's disease is an incurable illness. It affects about half a million people in Russia, and due to the general trend towards aging of the population the number of Alzheimer's disease cases will steadily increase. Insoluble deposits of amyloid beta in the brain tissue (amyloid plaques) are the major morphological characteristic of Alzheimer's disease. It has been found that the increased concentration of copper in amyloid plaques results in copper ions bound to the protein. It is the presence of copper in the binding site triggers of the formation of amyloid plaques. Therefore, the study of the binding site in amyloid beta is of great scientific interest. The local atomic structure of the Cu(I) copper ion binding site in the amyloid beta peptide has been studied by means of XANES spectroscopy. Several model structures obtained by molecular mechanics and density functional theory (ADF code) have been tested. Theoretical analysis of X-ray absorption spectra based on the finite difference method implemented in FDMNES code was performed. An appropriate model structure of the Cu(I) copper ion binding site in amyloid beta peptide has been found.

    Keywords: amyloid beta, binding site, Alzheimer's disease, the method of finite differences, Cu(I)

  • Calculation of the strength of reinforced beams with an aggregate of bimodulus of elasticity material with the use of different theories of strength

    The paper considers arbitrarily supported arbitrarily loaded reinforced, beam with an aggregate of bimodulus of elasticity material. Formulas for determination of the tangential stresses arising in the aggregate, subject to the reinforced elements. Formulas are obtained for principal stresses occurring at an arbitrary point in the aggregate, as well as the equation for determining the point where major stresses reach extreme values. Are terms of strength as the classical theories of strength, and strength criteria applied for calculation of constructions made of bimodulus of elasticity material.

    Keywords: reinforced beam, bielastic modulus, stress, normal concrete, strength criteria.

  • Accounting for the effects of differences between the moduli of elasticity in compression and tension in the calculation of the strength of reinforced beams with filler of foamy fibrous concrete

    The article investigates the impact on the normal stresses of inequality of the young modulus for tension and compression in the bending of reinforced beams. Obtained formulas for determination of the bending moments that arise in the fixture, compressed and stretched zone of the aggregate. Found the formula for the normal stresses arbitrarily supported reinforced beams, arbitrary cross section and arbitrarily loaded bending loads. For example, reinforced beams of rectangular cross-section shows the determination of the neutral line and maximum stresses.

    Keywords: reinforced beam, elastic modulus, stress, normal concrete

  • Statistical analysis of selections of exchange rates by means of rank criteria

    In presented article rank criteria for the statistical analysis of two selections are considered. These criteria check statistical hypotheses. Three groups of rank criteria were considered: about equality of the central tendencies, scopes of a variation and distribution laws. Researches were conducted on data on exchange rates in two next days in nine banks. Correctness of criteria was estimated proceeding from an US dollar exchange rate established by the Central bank of Russia. To these data rank criteria of Wilcoxon, Van der Waerden, Kolmogorov-Smirnov and others were applied rubbed. Coinciding values of two selections were estimated by means of a method of an average rank. For all examples rank criteria gave the correct assumptions of equality of two selections.

    Keywords: statistics, rank, sample, hypotheses statistical, critical value, normal distribution, the interfaced couples

  • Decomposition method in adaptive sonar systems design

    To study complex sonar systems, the method of decomposition was suggested. The peculiarities of the method applied to the sonar systems were considered. A four-level hierarchy of decomposition subsystems is proposed. A scheme of the first level of semantic decomposition was presented. Controlled modules allowed to build adaptive systems were described.

    Keywords: decomposition, hydro speaker systems, hierarchy of subsystems

  • Preconditions of low efficiency of public administration

    Article is devoted to definition of the main preconditions of insufficient efficiency of public administration. It is shown that the majority of the Russian regions has the investment rating characterized by the lowered potential together with moderate risk. Process of extensive building of the sphere of the state services, being accompanied decrease in its social and economic efficiency at the same time takes place.

    Keywords: public administration, state services, investment rating, expenses of the budgetary system, gross internal product