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  • Methods for the synthesis of LaMnO3 (Review)

    "This review covers various methods of synthesis LaMnO3 ferroics. The general analysis of the solid-phase synthesis reactions methods and wet methods (sol-gel, sorption, co-precipitation) are carred out. The original results of LaMnO3 syntheses from various precursors by means of the in situ method are showned. The advantages and disadvantages of different methods of synthesis are determined. The analysis of synthesis LaMnO3 ferroics published data is shown:
    - the structure formation of LaMnO3 in perovskite-type phases occurs at different temperatures, depending on precursors states;
    - LaMnO3 perovskite phases differ in symmetry and unit cells parameters at room temperature, depending on the preparation conditions;
    - the highest synthesis temperature of LaMnO3 are typical for solid phase reactions method (950-1050 ° C), the lowest - for wet synthesis methods (500-700 ° C);
     - the synthesis conditions effect the stoichiometry of LaMnO3 for oxygen content.
    Our studies of structure formation processes of LaMnO3 by in situ method are allowed to define the role of precursors states at synthesis of solid phase reactions methods, adsorption, co-precipitation and sol-gel mixtures.
    It is determined that in samples prepared by wet chemical methods, the formation processes of  LaMnO3 perovskite phases occur at lower temperatures than by solid phase reaction (sol-gel precursor - 500 <T <600 ° C; precursors obtained by coprecipitation and sorption methods - at 600 <T <700 ° C and 700 <T <800 ° C, respectively).  

    Keywords: ferroics, LaMnO3, X-ray diffraction, solid-phase synthesis, sol-gel synthesis, sorption, co-precipitation

  • Optimization of thick-walled concrete shell based on the solution of the inverse problem of mechanics of heterogeneous bodies

    We solved the problem of optimization of thick-walled prestressed concrete cylinder loaded by internal pressure. Preliminary stresses in such a cylinder are created by wounding with tension cables on the outer surface. The idea of the method is to find the law of variation of modulus of elasticity , in which the state of stress is given . The analytical dependence of modulus of elasticity of the radius at which the tensile stress in the entire thickness of the shell does not occure was found. By creation of indirect heterogeneity we reduced the consumption of rebar by 10%.  The direct problem - determining the stress- strain state of a cylinder with a constant modulus of elasticity was also resolved.

    Keywords: thick-walled prestressed concrete cylinder, optimization, inverse problem, theory of elasticity, heterogeneity

  • The calculation of the optimal value of the protective layer of concrete columns of square section

    An approach to the calculation of the optimal values ​​of the protective layer of longitudinally reinforced concrete columns, operating at a central compression. Modeling performed using FEM - Ansys package for the design and implementation of spatial models of flat section of the column.

    Keywords: reinforced concrete column, longitudinal reinforcement, a protective layer of concrete, finite element method, critical load

  • Increase of power efficiency of protecting designs - a way of increase of efficiency of operation of buildings and constructions

    The role of technical inspection as source of definition of an actual state of protecting designs is considered. Not destroying methods of definition of durability and thermal properties of materials of external walls are resulted. The thermographic method of not destroying control is considered, the list of thermal characteristics which can be defined with its use is presented. Modern requirements to thermal characteristics of external walls are presented and the materials most often meeting in protecting designs are considered. It is considered as a possible variant of increase of thermal properties of protecting designs - the device of hinged ventilated facades. The scheme of carrying out of a damage control, a substantiation of economic efficiency of the device of hinged ventilated facades and other technical advantages concerning other ways of warming of facades is presented.

    Keywords: Technical inspection, thermographic quality monitoring, thermal characteristics of protecting designs, hinged ventilated facade

  • The extent of the stress-strain diagram of eccentrically compressed concrete pillars

    On the basis of experimental data on the resistance of reinforced concrete columns eccentric compression was obtained analytical dependence of the limiting compressibility of concrete from the varied factors: the relative eccentricity of the external force eo / h and the reinforcement ratio μ.

    Keywords: reinforced concrete column, longitudinal reinforcement, a protective layer of concrete, finite element method, critical load

  • The choice of boundary conditions for the simulation of the temperature field of soil

    The existing methods of calculation of the annual change in soil temperature. Identified areas of their application and the possible deviations from reality. The requirements to the boundary conditions of the calculation. Defines the principles of the choice of initial conditions. The preconditions for the development of a universal method of calculation.

    Keywords: heat pump, renewable energy, solar radiation, transient mode, soil

  • Modeling technology changeover

    The paper examines the main approaches to the modeling of scientific and technical progress. Details the conditions and change the model postulates technological structure , its main provisions . Put tasks that are of great interest for scientists involved in the modeling of scientific and technological progress , and for economists who are interested in the practical application of these results . Values ​​of other well-known models of STP . The variants of modernization and the possible synthesis of these approaches to modeling change tehnologichekogo order.

    Keywords: scientific and technological progress, advanced technology, changing technological way of practical experience, the elasticity of factor capital

  • Sustainable development in forming of effective region transport and logistic system

    The analysis of a current status of region transport system was carried out. Main problems of public transport system were revealed and the directions of their decision were determined. Author suggest to use the concept of a sustainable development for the purpose of creation of sustainable transport and logistic system (STLS). The main components were considered, the basic principles of creation of STLS were systematized. Result of research is the complex of managerial measures and strategy of STLS directed on forming.

    Keywords: public transport, transport and logistic system, sustainable development, complex

  • Review of solid waste consumption as the dispersed system

    The analysis of the main approaches to the classification of waste. Revealed their shortcomings. A new approach to the classification of the position to consider the consumption of solid waste as a dispersed system. The main parameters that characterize the processes and phenomena observed in the waste.

    Keywords: Solid waste consumption, classification attributes, parameters properties of the waste

  • The algorithm of determination of mechanical characteristics of metal at calculation of a residual resource of cranes

    Is considered the main content of the possibilities for extending the services of the lifting cranes, on the basis of the definition of a residual resource of the machine. The algorithm is sampled( measurements) of the metal structures of cranes. A variant of transition from the hardness of steel to its  strength.

    Keywords: chapel strength, chapel, endurance, a residual resource, providing design, resource rationing, hardness

  • The development of the information market as a condition and a result of becoming an information economy

    The paper discusses the features of the development of the information economy in Russia. The analysis of the current stage of development. Structure disclosed information market: actors and segments. Reflects the dynamics of the development of the information market and the integration of the domestic information market. Software market in 2011 grew by 23.8% and amounted to $ 162 million major share of the Russian market controlled by big international suppliers .
    The main share of the Russian market of equipment controlled by big international suppliers , whereby these segments are also characterized by a low level of competition: the company's market share is 16 % AcerInc sales , SamsungElectronicsRus -14% of the market. Growth of the Russian market of equipment for IT- communications mainly determined by the development segment tablets and laptops .

    Keywords: information market segments of the information market, cloud computing market, problems, especially

  • The model predictive control system simulation for the catalytic cracking process of oil

    The especially the functioning of fluid catalytic cracking plant are considered. A mathematical model of a catalytic cracking plant is presented here. Implemented model identification based on experimental data. The predictive controller based on predictive control method for dynamic processes is developed. Effectiveness of the approach is confirmed by the results of catalytic cracking plant simulation. 

    Keywords: catalytic cracking, modeling, model predictive control, multivariate control system, optimization

  • Simulation re-routing strategies for the CBD network of Rostov-on-Don.

    This paper presents the results obtained at simulation of various algorithms dynamic route guidance. A simulation experiments has been executed for the CBD network of Rostov-on-Don with using AIMSUN package. The main objectives of research are estimate routing strategy and relation between shape of the macroscopic fundamental diagram and traffic assignment on the network.

    Keywords: re-routing, rate, dynamic traffic assignment, traffic conditions

  • Computation re-routing rate and traffic conditions to dynamic traffic rerouting

    In the implementation of dynamic re-routing of traffic it is important to notice that the threshold depends on the network layout and type of the roads. Full paper includes appropriate relationships, figures and analysis of simulation results to define the re-routing rate of dynamic traffic reroutig

    Keywords: re-routing, rate, dynamic traffic assignment, traffic conditions

  • Service as a markering and logistics category

    In the article was shown the essence of the concept of "service" from the standpoint of marketing and logistic activities, the service dualism, the assessment of service of marketing and logistic positions. In the article was made an attempt to differentiate service operations to marketing or logistics activities in the aim of improving the management process of customer service and competitiveness of the company

    Keywords: service, service management, logistics service, marketing service, service assessment