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  • Local atomic structure of gold nanoparticles in silica glasses by using to EXAFS and DFT modeling

    Plasmonic nanoparticles make it possible to localize the electromagnetic field at scales smaller than the optical wavelength. This property is useful for the application of same objects for the creation of nanodetectors, in the processes of energy conversion and storage, in the tasks of data processing and transmission. In particular, the creation of computer chips with plasmonic elements instead of traditional semiconductors will increase their performance and energy efficiency. Our main purpose is obtaining implanted in the matrix of glass the arrays of plasmonic nanoparticles with controlled optical properties. Their properties can be varied by changing the conditions of their synthesis and post-processing. Nanoparticles are created by UV-laser influence on the gold film, precipitated on the glass surface. One of the proposed methods is long-term heating at 300 ̊C of already synthesized samples. This research presents the results of the study of the effect of temperature treatment on the atomic structure of Au nanoparticles. The study of the nanoparticles atomic structure was performed by using EXAFS-spectroscopy at the Au L3-edge. EXAFS-functions were fitted by using Stepwise EXAFS fitting-code, obtained models of the NPs atomic structure were confirmed by using DFT-optimization. The fact, that the atomic structure of NPs before and afted thermal treatment is strongly dependent of the thickness of initial gold layer (6, 10 and 70nm), is established. These differencies can be explainde by different interaction between gold film & NPs and glass matryx.

    Keywords: nanoparticles, Au, nanoplasmonics, EXAFS, DFT, atomic structure

  • Effect of oxide additives on the structural properties of the cobalt catalyst for the synthesis of hydrocarbons

    The structural properties of cobalt catalysts and their active component are studied. The influence of metal oxides on the specific surface area, pore volume and size, the average crystallite size and the active surface area of the catalyst Co-Al2O3/SiO2 was studied.

    Keywords: Fischer-Tropsch synthesis, synthetic hydrocarbons, catalyst, cobalt, promoter, carrier, specific surface, porous structure, catalytic activity, degree of reduction, active surface area

  • Effect of modification of aluminum oxide on cobalt catalyst of Fischer-Tropsch synthesis promoted by manganese oxide

    The physical and chemical properties of cobalt catalysts promoted by manganese oxides for the synthesis of hydrocarbons by the Fischer-Tropsch method are studied. The influence of polymorphic modifications of the alumina carrier on the specific surface area, pore volume, degree of reduction, size of cobalt crystallites,catalytic activity, dispersion degree of catalyst reduction is considered.

    Keywords: Synthesis of Fischer-Tropsch, synthetic hydrocarbons, the cobalt catalyst, promoter MnO2, the carrier of Al2O3, specific surface area, the degree of recovery of the catalytic activity, dispersion, and the crystallites of cobalt

  • Hydroacoustic system with complex signals for communication and positioning of underwater vehicles

    The method of local positioning of underwater vehicles by hydroacoustic system with linearly-frequency-modulated probing signals is considered. The method is based on measuring the range to the object and calculating the angles of arrival of echo signals on two or more spaced antennas. To increase energy and noise immunity signals with linear frequency modulation (LFM) are used. The scheme of towing an underwater vehicle with an acoustic beacon and the location of a hydroacoustic interferometer with two receiving antennas on a towing vessel are presented. The possibility of practical use of this method for high-precision measurement of the spatial position of an underwater towed or Autonomous vehicle relative to a surface vessel and, accordingly, the possibility of geographical reference of acoustic images and sea-bottom profilograms obtained by an underwater vehicle is experimentally shown. The results of full-scale tests of the experimental positioning system for its testing in the coastal zone of a small pond are presented. The block diagram of the local positioning equipment is presented. Examples of experimental distributions of the power module of echoes over the range are given for correlation processing of the acoustic beacon LFM signals. The paper also proposes the use of narrow-band traverse broadband parametric systems for communication between Autonomous unmanned underwater vehicles (ANPA) moving "in a flock". Describes the main specifications of the system and the experimentally measured in hydroacoustic basin of the directivity pattern of the antenna at the average rate of pumping and difference frequencies. The features of signal propagation in shallow sea are presented.

    Keywords: hydroacoustic systems, side-view interferometric sonar, local positioning systems, parametric antenna, data transmission system, broadband antenna

  • Electrodeposition of a dispersed alloy of iron-nickel in stationary and non-stationary electric modes

    The process of electrodeposition of the iron-nickel alloy in stationary and non-stationary electric modes is studied. The influence of periodic currents of various forms and parameters on the rate of extraction of the alloy components, its composition, and also the current efficiency of the alloy is investigated.

    Keywords: iron-nickel alloy, current density, current efficiency

  • Calculation of the main beam of the production building

    The problem of calculating rods for vector perturbations consisting of five components is solved: 1. kinematic transverse vibrations of the left end; 2. kinematic transverse vibrations of the right end; 3. dynamic bending moment at the left end; 4. dynamic bending moment at the right end; 5 dynamic uniformly distributed lateral load along the length of the rod. The transfer functions from each disturbance are obtained separately. Using these functions, we obtained the elements of the spectral matrix for stationary random processes, taking into account their correlation. The most common types of processes are considered: exponentially correlated random process; process with latent periodicity (with characteristic frequency); truncated white noise. The formula for obtaining the dispersion of displacement of sections is shown.

    Keywords: rod, harmonic oscillations, natural frequency, kinematic disturbances, dynamic disturbances, transfer function, correlation matrix, random process, delta-correlated random process, latent periodicity, truncated white noise

  • PEST Analysis of the organization piggy

    The innovative development of the transport system of Russia through the organization piggyback transportation based on the technological interaction of railway and automobile transport is considered. The implementation of innovative solutions requires consideration of environmental factors, the assessment of which in this article was carried out by means of PEST Analysis. The characteristics of four groups of factors are given: political, economic, socio-cultural and technological. Their positive and negative impact on the innovation activity of the Joint Stock Company «Russian Railways» has been determined. Political and economic factors that require the development of strategic management decisions at the state level have the highest priority in terms of their influence on the introduction of piggyback transportation.

    Keywords: transport, piggyback, piggyback transportation, innovative development, factor, PEST Analysis

  • Econometric analysis of the import volume of the Republic of Kazakhstan

    The article describes a trend-seasonal adaptive model of the time series of the import volume of the Republic of Kazakhstan according to the quarter data in the period from 2013 to 2018. According to the obtained model, the forecast of the imports volume in the value terms for the first quarter of 2019has been made.

    Keywords: Republic of Kazakhstan, import, multiplicative model, exponential smoothing, adaptive model, forecasting, trend equation

  • Associative tools for multidimensional risk assessment

    The possibility of using associative tools to solve the problem of multidimensional risk assessment is substantiated: “language of associations” for the formalized presentation of risk events and risks in the form of information objects in an associative environment; associative environment for the implementation of such assessment procedures. The approach to modeling the processes of multidimensional risk assessment based on the associative environment with its implementation on the FPGA is substantiated.

    Keywords: associative environment, multidimensional risk assessment

  • Models of micromovements causing a turboprop effect

    An analysis of micromovements causing a turboprop effect or a micro-Doppler was carried out, analysis of model input data for building a function bank was performed, an algorithm for reducing the effect of a turboprop effect was considered, the expediency of forming a similarity function for the subsequent reduction of the effect of micromotion on an object

    Keywords: spectrum; radar; echo signal; turboprop effect; gliding component, micro-Doppler, radar

  • Experimental study of the passage detector

    The scheme and design of the detector operating in the range of operating frequencies from at least 1 to 1250 MHz are described. An experimental study of the frequency dependence of the voltage sensitivity B_u, as well as the amplitude characteristic at four frequencies. It is shown that the detector has a high frequency response uniformity and can be used in measuring and receiving-transmitting equipment.

    Keywords: the entrance detector, the voltage sensitivity, the amplitude, the unevenness of sensitivity on the voltage

  • Evaluation of the efficiency of heat utilization of flue gases of the boiler house

    This article presents the results of an experimental study of the deep cooling of natural gas combustion products in a condensation heat exchanger of a waste heat exchanger in a boiler house No. 12 at the Federal State Budgetary Educational Institution of Higher Education "National Research Ogarev Mordovia State University". The heat scheme of the boiler house with the flue gas heat exchanger provides the maximum continuous cooling mode. The study identified the factors that have the greatest impact on the efficiency of the heat exchanger-utilizer.With short-term operation of the boiler in the spring and autumn periods, the efficiency is more than 3%.

    Keywords: burner, combustion mode optimization, heat utilizer, boiler room thermal circuit, boiler unit, flue gases, condensation, heat exchanger, cogeneration mode, cooled gases

  • Selection of alloying elements to improve the machinability of powder structural steels

    Hot stamping of porous billets (GSPZ) is considered. Structural steels obtained with the use of GSPZ technology are significantly inferior in terms of machinability by cutting similar in chemical composition to cast and hot-rolled steels. Various alloying elements are considered to improve the machinability of structural powder steels by cutting and their effect on physical and mechanical properties.

    Keywords: powder metallurgy hot stamping of porous billets, GSPS, machinability, alloying elements

  • Investigation of the effect of Zr and Mn promoters on the properties of cobalt catalysts for Fischer-Tropsch synthesis

    The parameters of the porous structure and the active surface of cobalt catalysts for Fischer-Tropsch synthesis (SFT) prepared by the impregnation method have been studied. Characteristics of composition and porous structure were studied using elemental analysis and the Brunauer-Emmett-Taylor method (BET). The effect of the addition of oxide promoters on the specific surface area, pore volume and pore size of the Co / SiO2 catalyst has been studied.

    Keywords: Fischer-Tropsch synthesis, heterogeneous catalyst, promoter, carrier, specific surface area, porous structure, selectivity, activity, dipping method

  • Cobalt Fischer-Tropsch synthesis catalysts supported on Al2O3 of various polymorphic modifications

    The parameters of the porous structure and the outer surface of cobalt catalysts for the synthesis of Fischer-Tropsch, promoted by magnesium, prepared by the impregnation method according to moisture capacity, were studied. The effect of polymorphic modification (γ, θ, α) of the carrier on the physicochemical properties of the catalyst Co-Mg / Al2O3 was studied.

    Keywords: Fischer-Tropsch synthesis, polymorphic modifications of Al2O3, synthetic motor fuel, catalyst, carrier, elemental analysis, BET method, specific surface, porous structure