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  • Determination of the atomic structure of bimetallic Pt-Ag nanoparticles in metal-carbon catalysts by X-ray absorption spectroscopy data

    The atomic structure of bimetallic nanoparticles of Pt-Ag composition, which are the part of metal-carbon electro-catalysts PtAg/C, is studied by means of EXAFS spectroscopy using the suggested technique. These materials have been prepared by methods of consistent and simultaneous deposition of Ag and Pt atoms from aqueous ethylene glycol solutions of their salts with subsequent acid treatment. The values ​​of the structural parameters of the near environment of platinum atoms are determined. The nature of the distribution of components in nanoparticles is established. Cluster models of nanoparticles are constructed. The fraction of Pt atoms in the working shell and its dependance on preparation methods in each case are determined.

    Keywords: Metal-carbon electrocatalysts, bimetallic nanoparticles, Catalysis, Platinum, X-ray absorption spectroscopy, atomic structure

  • Technological methods of ensuring the fatigue strength of elastic elements

    As a rule, the information they have guides for fatigue testing geometrical designs, gives only the evaluation of the characteristics and design lay stock in several, and sometimes in tens times exceeds the tensile strength of the material. And saving of material, from the point of view of obsolescence, product should be developed on a certain resource. For details, which operate in the field of elastic deformations and calculated in operation for a given mode of operation should lay in the design of the guaranteed resource. To do this, for example, compensating coupling method is suggested, which is based on the calculation methods of CAD/CAM/CAE/CSE NX 7.5 and field tests considering the impact of technology of surface hardening. The character of strain in «elastic element» in NX 7.5. The calculations of the elastic element module «flexible body» NX 7.5, but due to the fact that the calculation is impossible to consider technological parameters of manufac-turing is conducted equivalent full-scale tests. Accordingly, designed and built a stand for equiva-lent tests. Finally, for comparison, is a computer simulation to calculate large displacements and complicated movements of the coupling. For this we used the application NX 7.5 «Simulation of kinematic mechanisms» with the attraction tools «Flexible body».

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

  • Methodology to evaluate the production of electric power systems

    To date, questions the reliability and continuity of electrical energy production facilities are among the most urgent , due to the transition generation companies into private hands and aggravate financial, economic and industrial- technological challenges : depreciation and obsolescence of equipment, lack of investment and other factors, influencing the power producers .
    The article discusses the various valuation techniques of industrial enterprises and industrial complexes electricity . On the basis of their proposed universal method of estimating production complexes electricity , which is divided into 6 groups and includes weights . The article noted that the proposed method of estimating the weight of electric power systems operation has several advantages compared with the methods of other authors.

    Keywords: electricity, electricity production complexes, investment, reliability, development

  • The methodological bases fuzzy cognitive modelling of hierarchical problem-directed systems

    This article is devoted to description of structure of methodology of modelling of hierarchical problem-directed systems on the example of social and economic systems. In the basis of methodology the principle of a combination of the formalized methods of modelling and expert procedures is put. Modelling of hierarchical system is offered to be spent by means of multilayered fuzzy cognitive maps. Filling of the block of logical-mathematical models in structure of process of decision-making is described in detail. The offered methodology provides the development and choice of well-founded administrative decisions.

    Keywords: Problem-directed system, decision making, fuzzy cognitive model, methodology

  • The definition of crisp dominating tactics for development of alternative control decisions in the conditions of total uncertainty

    The article is devoted to modelling of process of decision-making in difficult systems in the conditions of total uncertainty. The problem is formulated on the basis of synthesis of concepts of the control theory and decision-making, the theory of fuzzy sets and the fuzzy logic, the theory of hierarchical multilevel systems, the utility theory and the theory of games. The given concept expands possibilities of the account uncertainty the various nature, typical to mathematical description of the surrounding validity. Problems of search of decisions in an fuzzy hierarchical control system are designated. The way of the description and finding of alternative decisions in multilevel difficult systems is offered in given article. The algorithm is based on information processing in the form of fuzzy intervals taking into account two kinds the politician conservative and aggressive on the basis of criteria «maxmin» and «minmax». The method of projection on individual interval is used for comparison of the fuzzy intervals presented on various dimension scales. The example showing work of algorithm of a choice of two groups of alternatives is resulted: optimistic and pessimistic on a level of hierarchies of the purposes in the conditions of total uncertainty.

    Keywords: Difficult system; decision making, fuzzy interval, the control decision; total uncertainty

  • Rural fire insurance on Don (second half of XIX - early XX centuries)

    History rural fire insurance on the Don, analysis of insurance institutions Don Army (1870-1876), 
    regional rural council (1876-1882), the Regional Management Committee for Zemstvo Affairs (1882-1919). 
    The specificity of the insurance for the сossack population: collecting insurance payments stanichno and county boards, 
    the choice of the сossacks rated insurance, etc. 
    There was a preponderance of mutual insurance, analyzed the accumulation of insurance capital  

    Keywords: insurance, organization of insurance, business, Zemstvo insurance, mutual insurance, insured event, insurance valuation, insurance discounts

  • Technical and economical justification of the physic and mechanical compressed air drying method

    In the article the questions of technical and economical justification of the physical and mechanical compressed aitr drying are looked over. The detailed calculation  for price index and economic profit for wagon exploitation depot are given.

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

  • Spraying of nonisocyanate insulation foams

    This article describes a method for producing two-component nonisocyanate insulating foams and technology of its spraying on the insulated surface. It describes the device, which, along with standard equipment, includes principally new design of components pre-mixing chamber. Constructive solutions described in the article will allow using the compositions which have different time and temperature of curing than conventional PU foams.

    Keywords: Keywords: spray foams, insulating foams, nonisocyanate urethanes, pre-mixing chamber.

  • Multicriteria selection of the optimal database management system by using the analytic hierarchy process method

    This paper proposes criteria for the optimal choice of a database management system (DBMS), based on the requirements to this system. Empirically assessed criteria and method of analytic hierarchy process for decision making were used to carry out the comparative analysis of several DBMSs, implementing relation data model and having similar functionalities. The obtained matrixes of pair-wise comparison are examined for concurrence by calculating indices described in the article. As a result, the database management system for the own project is rationally chosen.

    Keywords: DBMS, method of analytic hierarchy process, criteria, matrixes of pair-wise

  • Some trends of development of computer simulation systems of goods functional performance and its market

    The article gives IT-companies and their software products review in the field of engineer analysis and calculation. The importance and intensive development of this sphere IT-companies through their works and service refining, that facilitates their new market segments introduction, is shown.

    Keywords: CAE, engineering, intellectual property, IT-technology, software products, CAD

  • Application of correlation functions for an assessment of an error of a form of details of cars in cross section

    Questions of use of the device of the correlation analysis for an assessment of an error of a form of details of cars in cross section are considered. It is shown that use of the considered device also effectively as well as application of traditional methods of an assessment of an error of a form, however demands smaller computing expenses

    Keywords: error, form, details, correlation, analysis

  • Environmentally responsible economic management saves water and energy resources

    The article highlights the issue of conservation of water and energy resources, the dependence of its decision on the environmental responsibility of business entities and tactical goals towards environmental management.  Also the essence of the work carried out in the production of ammophos is described (Hydrometallurgical plant, Lermontov town), which is a good example of solving one of the many tactical tasks in the direction of environmental management. Specific purpose of the work was to identify the savings reserves of energy and natural resources. The application object of the study is the energy-intensive production of ammophos (fertilizer complex of nitrogen and phosphorus compounds), in particular the boiling-down of ammoniated pulp. The load decrease by evaporated water by 75% is achieved the implementation of technical solutions in terms of sealing pumps work (replacing inefficient crevice seal on a metal face seal) installed on the circulation line of ammoniated pulp. This reduces the coolant flow for boiling-down of high pressure steam and drinking water saving, which is the raw material for the production of fluid. Ecological and economic efficiency of the proposed solutions is confirmed by the calculation of the expected technical and economic parameters, performed on the basis of data generated in monitoring: coolant saving - 3039 Gcal / y; 2430 rubles / g; drinking water saving - 11,477 rubles.

    Keywords: ammophos, boiling-down, coolant, drinking water, saving, environmental management, crevice seal, face seal.

  • Universal method of synthesis of optimal control of nonlinear Lagrang dynamic systems

    Universal method of optimal control synthesis offers a versatile method for the synthesis of optimal controls provides a solution to the synthesis problem for the class of piecewise constant functions for Lagrangian dynamical systems, the shape of the control law depends only on the structure of the cost functional and does not depend on the structure of the existing system of generalized forces. The effectiveness of the method is confirmed by a minimum of computational costs, as well as the maximum rate of convergence and accuracy to achieve the desired trajectory in comparison with the known solution for example has become a test for testing various control methods for the synthesis problem of a simple pendulum.

    Keywords: combined maximum principle, optimal control, mathematical pendulum

  • Thermal treatment of Fe-Co-V as an instrument to improve soft-magnetic material devices quality

    Thermal treatment of Fe-Co-V as an instrument to improve soft-magnetic material devices quality
    The process of optimizing the thermal treatment Fe-Co-V alloys used in the magnetic torque motors is studied in order to improve the magnetic properties. It is shown that to achieve high and stable magnetic properties of the alloy it must be annealed in vacuum using inactive coatings. Regime of the annealing process depends on the quality of the original alloy. Quality verification is carried out by measuring the magnetic properties of the control samples . Identifying optimal annealing regime is based on the analysis of a phase diagram of Fe-Co alloy. In connection with that the research of influence of the heating rate , maximum temperature and holding time , cooling rate on the behavior of the magnetic parameters of the control samples is carried out. It was found that the improvement of the magnetic properties is achieved by increasing the exposure time to 6h at the cooling rate of 100 °/hr. As a result a reduction of the coercive force (60 ÷ 50 ) A / m to (28 ÷ 32 ) A / m and increased magnetic induction of technical saturation from (2,0 ÷ 2,10) Т to (2,20 ÷ 2.26 ) T. for Fe-Co-V alloy are achieved. Research of the exposure time and the cooling regime caused a decrease in coercive force of the Fe-Co alloy.

    Keywords: Heat treatment , the annealing conditions , Fe-Co-V, technical saturation induction , the coercive force

  • The analysis of work of building elements hermetic shell nuclear power plant during preliminary tension and testing

    Design of the protective hermetic shell of the reactor compartment of the nuclear power plant discusses in the article. The possible deformation of elements of the hermetic shell during preliminary tension  and testing is considered

    Keywords: protective hermetic shell; change of form; deformation; strength tests