730 research outputs found

    Diffraction efficiency of photothermoplastic layers for the recording of discrete holograms

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    An experimental and theoretical study of the dependence of eta of a digital phase Fourier hologram of a point object on the amount of deformation delta and the discrete-structure parameters representing the hologram is detailed. An expression is given for eta. Experiments were performed on photothermoplastic layers based on polyvinyl carbazole and trinitrofluorenone charge transfer complexes. The maximum eta, 2%, is found at delta = 0.56 micron

    Low temperature plasma-catalytic NOx synthesis in a packed DBD reactor: effect of support materials and supported active metal oxides

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    The direct synthesis of NOx from N2 and O2 by non-thermal plasma at an atmospheric pressure and low temperature is presented, which is considered to be an attractive option for replacement of the Haber-Bosch process. In this study, the direct synthesis of NOx was studied by packing different catalyst support materials in a dielectric barrier discharge (DBD) reactor. The support materials and their particle sizes both had a significant effect on the concentration of NOx. This is attributed to different surface areas, relative dielectric constants and particles shapes. The nitrogen could be fixed at substantially lowered temperatures by employing non-thermal plasma-catalytic DBD reactor, which can be used as an alternative technology for low temperature synthesis. The γ-Al2O3 with smallest particles size of 250–160 μm, gave the highest concentration of NOx and the lowest specific energy consumption of all the tested materials and particle sizes. The NOx concentration of 5700 ppm was reached at the highest residence time of 0.4 s and an N2/O2 feed ratio of 1 was found to be the most optimum for NOx production. In order to intensify the NOx production in plasma, a series of metal oxide catalysts supported on γ-Al2O3 were tested in a packed DBD reactor. A 5% WO3/γ-Al2O3 catalyst increased the NOx concentration further by about 10% compared to γ-Al2O3, while oxidation catalysts such as Co3O4 and PbO provided a minor (∼5%) improvement. These data suggest that oxygen activation plays a minor role in plasma catalytic nitrogen fixation under the studied conditions with the main role ascribed to the generation of microdischarges on sharp edges of large-surface area plasma catalysts. However, when the loading of active metal oxides was increased to 10%, NO selectivity decreased, suggesting possibility of thermal oxidation of NO to NO2 through reaction with surface oxygen species

    Development of students’ scientific society of Sochi state university for tourism and recreation

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    The article concerns the development of students’ scientific society of Sochi State University for Tourism and Recreation. Special attention is attached to students’ scientific work and occupational guidance activities, aimed to involve schoolchildren in research work

    Perspective directions in the development of architecture of the polytechnic museums

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    The museums of science and technology (or polytechnic) highlight the process of the innovational development of the society and have their own place in the system of school-science-industry-technical culture. The innovational activity of certain regions, states or groups of states is comprised of inventions, discoveries, new products and technologies that is all that provides the development of society and its competitive advantages. The modern polytechnic museums combine not only the functions of the demonstration of the achievements of the scientific and technological progress but also training and development of new inventions. In connection with the multifunctional nature of the modern polytechnic museum architects face the challenge of the creation of the architecture with universal dimensional planning elements, with its possible transformation in the course of time.Keywords: museum; science; innovations; technology; typolog

    The reactivity of 1, 3, 2-diheterophosphacyclanes containing a pentacoordinate phosphorus atom

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    Studies on the reactivity of λ5-1, 3, 2-diheterophosphacyclanes obtained during the last ten years are examined and described systematically. Data concerning new prototropic and elementotropic processes involving derivatives of pentacoordinate phosphorus are presented. Attention has been concentrated on the elucidation of the influence of the incorporation of a phosphorus(V) atom in the ring on the reactivity of phosphoranes in reactions of various types. The role of phosphorus(V) compounds as intermediates in reactions of phosphorus compounds involving different types of coordination of the phosphorus atom is demonstrated. © 1985 IOP Publishing Ltd

    Effect of the structure of functionalized phosphoryl carriers on the membrane transport of proton-donor substrates

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    A series of phosphoryl compounds functionalized in the side chain were synthesized, and their membrane-transport properties with respect to proton-donor substrates of various acidity were studied. It was found that the efficiency of phase transport of the strong monobasic perchloric acid correlates with the basicity of the phosphoryl carriers in a series of carriers containing oxygen-containing functional groups. The transport flow sharply increases in going to phosphorylated amines, whereas phosphoramidates in their efficiency are closer to phosphonates than to amines. The efficiency of transport of dibasic acids (oxalic and tartaric) is low, since the hydroxy and carboxy groups not bound to the carrier make ionic associates highly hydrophilic. Fine details of the structure-transport acitivity relationship in the series of phosphorus compounds were discussed. Three-dimensional correlation analysis was used to compare the structure of the carriers with their characteristics: basicity of amine centers, atomic charges of oxygen and nitrogen, and hardness and hydrophobicity parameters. © Nauka/Interperiodica 2006

    METHODICAL APPROACH TO AN ASSESSMENT OF A LEVEL OF QUALITY AND COMPETITIVENESS OF GOODS

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    In the article it is proved that marketing is one of the most effective mechanisms of regulation of a level of quality and competitiveness of production. It is offered to estimate a level of quality and competitiveness by means of indicators of norm and mass of potrebitelny cost of goods. Possible approaches to definition of these indicators are shown

    METHODICAL APPROACH TO AN ASSESSMENT OF A LEVEL OF QUALITY AND COMPETITIVENESS OF GOODS

    Get PDF
    In the article it is proved that marketing is one of the most effective mechanisms of regulation of a level of quality and competitiveness of production. It is offered to estimate a level of quality and competitiveness by means of indicators of norm and mass of potrebitelny cost of goods. Possible approaches to definition of these indicators are shown

    Reaction of Trichloro(o-phenylenedioxy)phosphorane with Four-Coordinate Phosphorus Esters

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    Reactions of trialkyl phosphates and dialkyl alkenylphosphonates with trichloro(o-phenylenedioxy)phosphorane result in selective replacement of one alkoxy group on the phosphorus by a chlorine atom. Alkylphosphonates react with trichloro(o-phenylenedioxy)phosphorane to give alkyl alkylphosphonochloridates as the major products and small amounts of alkylphosphonic dichlorides

    Reaction of Potassium Salts of N-(Thio)phosphorylthioamides with Chlorinated 1,3,5-Triazines

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    Potassium salts of N-(thio)phosphorylthioamides can substitute one, two, or three halogen atoms in chlorinated 1,3,5-triazine molecules to give the products of imidothiyl structure. At low temperature, products of incomplete substitution of halogen in the starting 1,3,5-triazines can be obtained
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