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
The ability to choose the right anti-wear additives [1-6 ] allows you to create lubricants , which are thin layers have different properties than in large volumes. It is commonly assumed that the additives are functioning only in the zone boundary lubrication and are outside the scope of the hydrodynamic theory of lubrication . However, the beneficial effect of additives as indicated in many studies [1-5 ] we have in the " thin layer" of hydrodynamic lubrication .As is well known , lubrication bearings operate on different types of lubricants which are composed of base oil and additive compositions that provide the required functional properties of the oil . Additives polymers with high molecular weight oils impart viscoelastic properties . Analysis of existing studies [ 7-9] on the calculation of bearings running on a viscoelastic lubricant , shows that they do not take into account the dependence of the viscosity and shear modulus of the pressure and temperature, and mode of friction is assumed laminar. It is known [ 10 ] , high-speed bearings operating in turbulent friction , higher pressure and higher temperature, and so the development of methods for calculating the bearings running on a viscoelastic lubricant requires consideration of the above factors.In connection with the above written shall first develop the computational model of thrust bearings running on micropolar lubricant with the viscosity characteristics of the lubricant on the pressure in contrast to the existing theoretical models do not take into account these dependencies (task 1).And then consider the calculation model of extra load -bearing capacity , working on a viscoelastic lubricant for the dependence of its characteristics on the pressure (objective 2).
Keywords: thrust bearing with the abutment surface adapted, non-Newtonian lubricants
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
The problems of building the architecture and design of the database structure for the storage of the structure of the chemical compounds and their analysis using heuristic algorithms
Proposed the structure of the database that allows you to store information about the structure of chemical compounds with varying degrees of detail. This approach simplifies forming of the structural descriptors used to build models of "structure-property" based on the genetic algorithms.
Keywords: database architecture, chemicals, data mining, heuristics
Information base of textile textures and materials, with the detailed description of the software for work with base is considered. It is told about methods of creation of base of textile textures and materials and about opportunities of the represented project.
Keywords: informatsionnno base, textile industry, texture, materials, visualization, software, graphics
The article is concerned with designing online identification algorithm for identification plunger model for wicket gate of Kaplan turbine adaptive control system. Algorithm is based on generalised recurrent least square method and invariant embedding method. Computer modeling using designed algorithm and using real experimental data shows that algorithm is effective.
Keywords: adaptive control system, diagnostic system, Kaplan turbine wicket gate, plunger, linearized models, identification, recurrent least square
With the use of pulsed laser deposition and carbothermal synthesis а photosensitive structure on the basis of the Schottky barrier Au/ZnO(nanorods)/ZnO(film)/ZnO(nanorods)/Au was obtained. The parameters of the carbothermal method of synthesis of nanorods ZnO were optimized. Under directly applied bias of 7V current sensitivity of luminous flux for this photodetector is observed in the UV and visible regions of the spectrum, and is 0.14 A/W - for 325 nm and 0.18 A/W - to 405 nm, which means that this structure has the ability of potential applications in various fields for the control of UV radiation (for example, for the monitoring of solar UV radiation, control of UV radiation in air and disinfecting water devices).
Keywords: ZnO nanorods, Schottky barrier, photodetector, photosensitivity
ZnO nanorod arrays have been synthesized on silicon wafers by chemical vapor deposition (CVD) technique with different temperature modes, without metal catalyst. With this method vertically aligned ZnO nanostructures were grown at the quite low temperatures. Modification of the method allowed to place silicon substrates in areas with different ratios of concentrations of the molecules in the vapor phase. Photoluminescence spectroscopy and electron microscopy studies have shown that morphologies and optical properties of nanorods depends on different ratios of concentrations of the molecules in the vapor phase.
Keywords: ZnO nanorods,chemical vapor deposition (CVD), photoluminescence
The arrays of ZnO nanorods were obtained on the sapphire substrates by means of pulsed laser deposition under the high pressure of argon. The conditions of synthesis were optimized, and their influence on the morphology of ZnO nanostructures were revealed. It is shown that the concentration of oxygen vacancies in ZnO nanorods can be changed by regulation of the synthesis temperature from 850 to 915 °. This process can be controlled by the ratio of intensities of the photoluminescence emission in the visible and ultraviolet regions. So, it allows to create nanostructures for UV photodetectors or chemosensors depending on the temperature choice.
Keywords: ZnO nanorods, laser deposition, PLD, photoluminescence
This paper outlines the implementation of computer model of second-order visual mechanisms that are specific to spatial contrast modulations, and represents the results of testing the model. Computer simulation is based on "Filter-Rectify-Filter" model with some important additions. The inhibitory parts of receptive field of simulated mechanism are non-selective to orientation and spatial frequency of texture elements. Texture modulated by orientation or spatial frequency does not reduce flank inhibition and does not activate the mechanism. Unmodulated texture also does not cause activation of the filter because the flanking inhibition will be equal to or exceed the excitation. However, increasing the contrast in the center and reduction it on the flanks leads to the activation of the second order mechanism.
Keywords: Second order visual mechanisms, image filtering, texture, spatial modulation, computer simulation
The work is devoted to the study of algorithms of control subsystem as part of the integrated onboard control system of the aircraft and used in the final part of the trajectory. Algorithms of control subsystems are synthesized on the basis of the theory of optimized delta-transformations of the second order using the principle of the inverted pendulum on a cart. The studies based on the simulation using the developed software model, allowed to estimate as the impact dispersion, and the contribution to it of various subsystems.
Keywords: terminal control, aircraft, on-board integrated control system, optimized delta transformation of the second order, autonomous short range radionavigation system, simulation, software model
In this paper the technology of repair of ground water retaining structures soil mixture improved quality with and without soil mixture install.Use soil mixture , improved sharps and ensure the return of ashes (repaired ) slopes and ridge structures of high strength (up to 13-15 MPa) and water resistance , thus increasing the effectiveness and quality of the repair work and increased resistance to the elements of the structures induced defect . The presence of the bran soil mixture not only enhances the strength of 30-40% , but also gives a significant increase in water and frost (20-30 %), which prevent or substantially reduce the infiltration of water through the filtration body water retaining structures , since high strength and frost soil-concrete being laid on a slope ( in the recovery slope failure ) and groove (at soil dumping and capacity to or in excess of the design marks ) will reliably protect the body of the dams ( dams ) of the drawdown , erosion , buckling , suffusion , and other deformities.
Keywords: technology, dribble feed , soil mixture, sift, cement, fly ash, dam, construction and repair operations, soil mixture installation, factors plan of the experiment, the regression equation
In the article authors examine specificities of internal components behavior changing in fiber-optical cable under influence of strong variable uniform electromagnetic field. There are some process variations proposed for describing of obtained results.
Keywords: fiber-optical cable, electrothermal degradation, kevlar, conductivity, open fiber-optical cable, partial discharges, water treeing
The article describes peculiarities of modern syntax parser systems and problems originating in text analysis. As a result of comparative analysis the authors propose a unified approach to processing of unstructured texts in Russian and English which combines morphology and syntax processing. The developed syntax analysis system, using verbs’ valency dictionary, samples of minimal structural schemes of sentences and samples of conjunctions, allows choosing predicative structures of sentences in the text, realizing initial semantic analysis due to semantic content of predicate’s actants and building trees of syntactical subordination of sentences. The derived trees hold elements of tree of constitutives and tree of dependences. The proposed samples and rules organization allows resolving some of the problems of modern parsers. And the use of verbs’ valency dictionary allows reducing the number of sentences syntax analysis variants.
Keywords: automatic text processing; syntax parser; morphological analysis; structural text elements
In this work experimentally investigated the possibilities of the new method of obtaining adjustable roughness on metal surfaces electrothermal influence of mobile cathode spots in vacuum arc discharge. Presents the results of processing of various surfaces using this method. Proposed working modes of processing of metal surfaces with the aim to receive as minimum and maximum roughness.
Keywords: roughness of metal surfaces, vacuum arc discharge, cathodic spots