National research technological University

Moscow, Russia

National research technological University

Moscow, Russia
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Baskov S.N.,National Research Technological University | Litsin K.V.,Magnitogorsk State Technical University
2016 2nd International Conference on Industrial Engineering, Applications and Manufacturing, ICIEAM 2016 - Proceedings | Year: 2017

The article provides a detailed description of the system of vector-pulsed start with intermediate transformers. The proposed scheme includes a sensor-less determination of the angular position of the rotor. It will increase reliability of the system and reduce its cost. Furthermore, this configuration enables limiting inrush currents. The article is based on a comparison of the system of vector-pulsed start with intermediate transformers and without them. We have analyzed the dynamic and energy characteristics of the system. Oscillograph of the torque and speed has been analyzed. Power measurement circuit of vector pulse-start is presented. Power currents are analyzed. The conclusion about possible use of intermediate transformers is made. Thus, the use of intermediate transformers increases starting and loss of time in the system, but reduces the value of the circuit power. © 2016 IEEE.

Peshkova M.Kh.,National Research Technological University | Popov S.M.,National Research Technological University | Stoyanova I.A.,National Research Technological University
Gornyi Zhurnal | Year: 2017

The technical approach described in the article allows justifying the economic expediency of production using mining waste. The production can be beneficial in many instances, owing to adjacency of business agents engaged in manufacturing, distributing, consuming and exchanging activities. The approach is based on the evaluator of the local market capacity relative to mining waste conversion products. In order to find the capacity of markets relative to waste products, the algorithm contains a procedure of overlapping of contour lines of consumer costs set for the mining waste conversion products and contour lines of costs of the analogous value products delivered from the remote areas relative to the market under analysis. As a result of the overlap of the contour lines, preference (competitive ability) segments are revealed in the local markets for the products manufactured from waste.

Tyushkova N.,National Research Technological University
Inzynieria Mineralna | Year: 2015

The important nature-protection value, when developing the mineral deposits, belongs to the technologies directed first of all on the increase of extraction of useful components from the ore minerals at reducing the volumes of dump products and decreasing therein the content of harmful admixtures that considerably reduces a level of contamination to the environment and the other negative ecological effects [1-6]. Taking into account dramatically increasing requirements to the environmental protection, there have been developed the low-waste technology to extract gold and silver from gold-containing quartzites with the use of waste waters in circulation. In conducting pilot tests to improve the reliability of quantitative determination of valuable components from ore, is the use of reliable and accurate sampling system. Thus large amounts of ore are being processed [7,8]. And as critical is the accuracy of the analytical methods for the determination of these valuable components in the original ore, as well as in the intermediate products of enrichment, the final concentrate and final tails. In the presence of free gold in the ore in determining it from hard products and rock ores the error probability increases significantly [9,10]. The purpose of this research was to test the technology developed in the enrichment of gold quartzite in semi-industrial conditions, as well as the interpretation of analyses' results when testing enrichment's technology of precious metals from gold quartzite. The results of process studies of ore showed that the most effective of the tested methods appeared to be the direct cyanidation of crushed ore up to 95% cl. -0,08 mm. In this regard, the extraction of gold ranges from 91,7% to 100%, and silver - from 48% to 68% and with content of precious metals in dump cakes left the traces - 0,2 g/t on gold and 9,7-6,4 g/t on silver accordingly. A scope of processed ore, a study of all the factors at desalinization of precious metals, milling fineness of the ore, influence of the pulp density, concentration potassium cyanide and lime as well as the kinetics of the process, allow insisting that the obtained results will be fully reproduced at the industrial processing of quartzites of the field, but they are also may be used for designing the mobile module unit to extract precious metals for the given type of ores [11-14].

Peshkova M.Kh.,National Research Technological University
Gornyi Zhurnal | Year: 2017

In focus are the issues of development in industrial regions based on management of man-made mineral formations (MMF, understood as man-made deposits left after mine closure, i.e. mine waste), which will allow replenishing mineral and raw materials supply base, creating extra jobs and improving considerably ecological situation. The participation of the state in socio-economic development in industrial regions in the form of developed legally enforceable enactments and effective Federal Laws in the territories of special status aimed at increase in their investment attractiveness is assessed. For the evaluation of investment attractiveness of MMF management projects in the territories of advanced socio-economic development and for the cost-To-use analysis of the governmental support of such projects, the author proposes the probabilistic financial model accounting for risk. The model is based on the appraisal of a project net present value determined through introduction of money flows with a certain increase in their variation as a forecast period extends, with regard to general and specific kinds of risk. The objective function in the model is the increment (or at least non-shrinkage) in net present value with allowance for the risk component in proportion to the extension of the project implementation period and for the positive NPV by the final date. NPV is calculated with account for the correction of money flows by the value of their possible scatter in conformity with the assumed confidence probability. In this case, positive money flows are corrected towards lower values, and correction of negative money flows is towards higher values. The efficiency or significance of the governmental support of specific projects is suggested to evaluate from the standpoint of the decrease in investment risk. The application of the proposed model is exemplified by evaluation of potential processability of coal mine waste.

Baskov S.N.,National Research Technological University | Litsin K.V.,Magnitogorsk State Technical University
2015 International Siberian Conference on Control and Communications, SIBCON 2015 - Proceedings | Year: 2015

The article deals with sensorless method for determining the angular position of the rotor of a synchronous motor by means of superimposing a high-frequency signal. The scheme of the laboratory stand for the experiment to determine the angular position without the use of the position sensor was made. A technique for determining the angular position of the rotor with an accuracy of 30°was described. The logic diagram for its implementation was presented. The derivation of the formula for the calculation of the angular position of the synchronous motor rotor was presented. Findings during the experiment for determining the angular position sensorless were analyzed. Conclusions to reduce the cost and size of the drive system and increase its reliability were presented. © 2015 IEEE.

Kekalo I.B.,National Research Technological University | Mogilnikov P.S.,National Research Technological University
Inorganic Materials: Applied Research | Year: 2016

The influence of annealing time on the ductile-brittle transition temperature (embrittlement temperature) Тf in amorphous Co-based alloy Со69Fe3.7Cr3.8Si12.5B11 with extremely low saturation magnetostriction λs (λs < 10–7) is investigated. It is revealed that the embrittlement temperature Тf dependence on annealing time ta can be described by the Arrhenius equation. Embrittlement at annealing temperatures higher and lower than 300°С can be described by different kinetic parameters owing to the different states of the amorphous phase. It is shown that, in the studied alloy, the embrittlement proceeds in a very narrow annealing temperature range, not exceeding 5°С. On the basis of experimental data on the evolution of hysteresis magnetic properties during isochronous annealing and isothermal exposure, the thermal treatment mode is investigated, providing rather high values of permeability μ5 (Н = 5 mOe, f = 1 kHz) of about 50000, without transforming studied alloy into the brittle state. © 2016, Pleiades Publishing, Ltd.

Andreev Y.Y.,National Research Technological University
Protection of Metals and Physical Chemistry of Surfaces | Year: 2012

It has been established that there is a quantitative relationship between the experimental value of hydrogen overvoltage, a =ηH 2 , in the Tafel equation and the surface energy, δU S, of metal with fcc and hcp structure, which is calculated theoretically in metal surface physics. An equation of slow discharge of hydrogen ions on metal is deduced, in which the a value is a linear function of the value δU S/αF where δU S is the minimal surface energy of the specified metal, α = 0.5 is the transition coefficient, and F is the Faraday num-ber. A prevailing tendency toward a decrease in hydrogen overvoltage on polycrystalline surfaces of metals with fcc, hcp, and bcc lattices with an increase in the minimal surface energy related to the appropriate (111), (0001), and (110) facets of these lattices has been observed. Results of analysis of the relationships between ηH 2 and the surface energy of metal are interpreted within the theory of active centers for heterogeneous catalysis with involvement of a thermodynamic model of the metal surface enriched with atom vacancies. © Pleiades Publishing, Ltd., 2012.

Filippov E.S.,National Research Technological University
Russian Physics Journal | Year: 2016

On the basis of the assumption of the electron density fluctuation at the band degradation, a calculation parameter (the radius R) of the half-width of the probability distribution over the coordinate R is identified at the level of the maximum electron density fluctuation (at a maximum of the Gaussian function). Based on an analysis of the crystallization process and high polymorphic transformations bcc → fcc, the reasons for the formation of bcc, fcc, hexagonal, and tetragonal structures from the liquid phase, as well as for the high temperature bcc → hcp transition in the solid phase are established using the calculated parameter (the radius R) in the solid and liquid phases. © 2016, Springer Science+Business Media New York.

Belashchenko D.K.,National Research Technological University
High Temperature | Year: 2015

A multiparticle potential of a new type (EAM-2) including the degree of crystallinity of atoms as a parameter is proposed for metal systems. This potential is based on the potential of the embedded atom model (EAM). The degree of crystallinity of atoms is determined by the expansion of the radius-vectors of neighboring atoms over spherical functions and the calculation of the characteristic q6. The potential EAM-2 describes well the properties of liquid, BCC, and FCC lithium at normal and high pressures. The equilibrium curves of BCC-lithium–liquid and FCC-lithium–liquid are calculated at pressures up to 40 GPa, and good agreement with the experiment including the maximum on the melting curve is obtained. Tables of the pressure and temperature dependences of the density and energy of the models are given. The anomalous behavior of the density of BCC and FCC lithium in the pressure interval of 25–30 GPa (increase in the density during isobaric heating) is noted. © 2015, Pleiades Publishing, Ltd.

Godymchuk A.,Tomsk Polytechnic University | Arzamastseva E.,Tomsk Polytechnic University | Kuznetsov D.,National Research Technological University | Milyaeva S.,National Research Technological University
Journal of Physics: Conference Series | Year: 2011

The dispersion of suspensions based on nanostructured powders (ZrO2 and Y2O3) and the simplest physiological fluids (phosphate buffering saline, glucose solution, water) in terms of their use in ecotoxicological tests was studied. Using the scanning electron microscopy and laser diffraction, an increase in the size of particles and agglomerates in the suspensions in 2-11 times was shown. The particle size distribution in the suspensions was characterized by a single peak, but its magnitude and width varied ambiguously upon standing suspensions in time. It was shown experimentally that the average size of the dispersed phase could rapidly grow in the DW-suspension, could be stabilized in PBS-suspension and might decrease with time in Gl-suspension. By electro-acoustic method it was shown that the Zeta-potential on the solid/liquid boundary in the study varied over a wide range of values from - 200 to + 200, and the nature of change - a jump. This demonstrated the instability of the suspensions based on NP-ZrO2 and NP-Y2O3.

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