Статьи журнала - Журнал Сибирского федерального университета. Серия: Техника и технологии
Все статьи: 1404
Development and experimental research of materials for forming stable bottom and side ledges
Статья научная
The main purpose of this paper is to find a solution for saving energy in the cell room. Another purpose of the paper is to find materials suitable for stable side and bottom ledge formation, research the properties of such materials, and study their behavior in cryolite-alumina melts, including selection of the most suitable material. Moreover, the paper is concerned with energy consumption reduction by forming stable side and bottom ledges. Furthermore, as mentioned earlier, several materials have been selected to form stable side and bottom ledges during the post-start-up period. The properties of the selected materials have been analyzed.
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Статья научная
Proposed new compositions of solder alloys based on silver. Developed technological schemes of production of wire diameter 1,2 mm. Developed scheme of production of wire diameter 1,2 mm from alloy SAg-40I with operation combined casting, rolling and extruding. Modeling of temperature-rate parameters of the process of combined casting, rolling and extruding has been made. Designed and constructed the installation CCRE-80. The analysis of the structure and properties of semi-finished solder alloys based on silver has been done.
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Статья научная
Recently materials on the basis of multipurpose alloys with special mechanical and physical properties are widely adopted for creation of equipment of new generation. Such materials include Invar alloys with a minimum value of thermal expansion with high strength characteristics and hardness. Results of complex researches on influence of the modes of heat treatment on formation of structure are presented in article on the example of an alloy 32NUFM.
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Статья научная
Developed algorithms, software, and calculation methods of deformation regimes and power parameters for cold bar rolling and drawing of rods and wires of gold alloys 585 standard. Obtain a formula for the calculation of the contact area during rolling in calibers similar in form to the rhombic. Presented the results of analysis factory regimes and proposed new routes of rolling and drawing, which have passed tested to obtain commercial pilot batches of jewelry chains.
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Статья научная
The processes of sulphiding roasting of arsenopyrite concentrate with arsenic sulfi de transition into the gas phase have been studied under laboratory and large-scale laboratory conditions. The roasting shall be carried out in neutral atmosphere (nitrogen or complete fuel combustion products), pyrite concentrate is recommended to use as sulphidizer, mixture of arsenopyrite concentrate and sulphidizer previously undergoes briquetting. Sublimates produced from roasting have been investigated by biotest methods, their correspondence to Hazard Class IV has been determined. Based on the investigation results, the process of gold-containing arsenopyrites treatment to produce low-hazardous sublimates and calcine suitable for further gold recovery has been proposed.
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Статья научная
Investigation into the causes of the ecological crisis is possible as a result of multicenter studies of the coast and off-shore strip. The development of unified technical and methodological approaches in the assessment of the impact of contaminated subterranean water on the ecosystem is the basis for complex geological-geophysical, geological, geochemical, hydrochemical, hydrological, hydro biological, microbiological, landscape, diving and other researches. Complex study management involves processing of large amounts of distributed data accumulated during the studies, and needs for their integration and analysis, require the use of modern methods, use of information technology (IT) and tools to support scientific research. Since the studies are interdisciplinary and require the prompt presentation of materials from a large number of scientists from different fields of knowledge, such a system must be multiple-user. Because of the spatial nature of the data, geoinformation systems (GIS) are a suitable tool for the research support on the anthropogenic impact on the ecology of any territory...
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Development of electrical wiring automated design algorithm
Статья научная
Nowadays, 3D electrical wiring design automation is less covered by EDA&CAD systems, than its other aspects (solid modeling, simulation analysis, printed circuit boards development). This article offers an algorithm of electrical wiring design automation realization and an algorithm of computer aided development of design documentation package for electrical wiring aspect. The algorithms are based on EDA system Altium Designer and CAD system SolidWorks. As a case study, existing instrument manufacturing plant was taken.
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Статья научная
In this paper, we consider the development of methods for determining the optimal location of symmetrization devices for 0.4 kV power supply systems with motor-actuated load. The methodology includes the features of electric consumers and their geographical location. The practice procedures for application of the existing power supply system the Taptugary village, the Mogochinsk region, the Trans-Baikal Territory was given as an example. The practical significance for the developed application procedures was justified. The optimal solution of balancing problem based on economical parameters was obtained.
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Development of rolled and cabling-wiring production from aluminum alloys at plants in Russia
Статья научная
This article provides an overview the state of production and consumption cabling-wiring production, plates, sheets and foil from a different aluminum alloys in Russia, CIS and other countries. Also the forecast consumption of aluminum semi-finished products in the coming years.
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Статья научная
This work describes the technology to identify firebreak plowing objects based on the satellite data of the Earth Remote Sensing within the medium and high special resolution.
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Development of wear-resistant parts of high-manganese modified 110G13L brand steel
Статья научная
The efficient operation of the technological equipment of machinery manufacturing enterprises and heavy industry without distortion depends in many respects on the strength of their details. This requires the study of the process of operation of the details, which are mainly rubbed with each other. These methods are widely used in obtaining high-quality steel castings. The simplest method of processing steel outside the oven is modification. Modified carbon steel is much more economical in properties approaches to leached steel, while modified steel leached by saving and investigation approaches leached steel with valuable and rare additives (Ni, Mo, Ti and other). Modification with alkaline and alkaline-earth metals greatly increases the quality of steel. The quality of steel is positively influenced by nitride-forming modifiers.
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Статья научная
Results of diagnosis of temperature anomalies based on retrospective analysis of long-term time-series of temperature in separation zone of troposphere and stratosphere over epicenters of 10 strong earthquakes with magnitude of M>6.5 that occurred in different seismically active regions of Asia are presented. Anomalous temperature perturbations were observed in all the studied cases 1-8 days before the main seismic event.
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Direction finding in satellite systems
Статья научная
In article the method allowing to determine coordinates of a source a radio emission located on a terrestrial surface in satellite systems with use of the geostationary satellite is stated.
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Directional characteristics of circular scanning aperture
Статья научная
In this paper explicit analytical expressions are derived which describe basic directional characteristics of circular scanning aperture: radiation pattern for different kinds of amplitude distribution, beamwidth, part of radiated power contained in the main lobe, directivity. Consideration is based on the theory of continuous ring radiator within the scalar approximation.
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Статья научная
The development of fast, qualitative and quantitative material characterization methods is one of the most important current issues in the field of nanosystems metrology. On this evidence it seems to be important to conduct a research on the capabilities of multimode resonance imaging mode in atomic-force microscopy (AFM) that allows broadening AFM capabilities in quality of nanonscale structures metrology and nano-object image quantitative analysis. The subject of this paper is modeling of physical phenomena that arise during the creation of such systems that describes coherent mechanic and electric phenomena in self-sensing and self-actuating cantilevers operating in multi-frequency resonance mode. The outcome of the research is represented by a virtual dynamic AFM model that allows understanding the signal generation process in AFM control and measuring circuits during sample scanning in multi-frequency mode.
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Effect of changing the symbol rate of QAM modem on the performance of 32kb/s ADPCM system
Статья научная
This paper presents three models of Quadrature Amplitude Modulation (QAM) modem operating at data rate of 16.8kb/s to be transmitted over 32kb/s Adaptive Differential Pulse Code Modulation (ADPCM) channel. These modems operate at symbol rates of 2400, 2800, and 3360 baud with associated number of bits per symbol of 7, 6, and 5 respectively. The performance of ADPCM is studied considering these modems with different constellations. The simulation results show that the performance of ADPCM degrades as the symbol rate decreases or number of bits per symbol increases. Also, the performance with circular constellation is better than rectangular one.
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Effect of neodymium and erbium on the kinetics oxidation of Zn0.5Al zinc alloy, in solid state
Статья научная
Thermogravimetrical method studied the effect of alloying additions (on 0.01÷1.0 wt%) of neodymium and erbium on the oxidation kinetics of Zn0.5Al zinc alloy in the temperature range of 523-623 K. The values of the oxidation rate of the Zn0.5Al alloy and the alloy alloyed with neodymium and erbium, have been established in solid state. The behavior of ternary alloys with the participation of neodymium and erbium at the indicated temperatures somewhat differs from the oxidation of the binary Zn0.5Al alloy. For the eutectoid Zn0.5Al alloy, as compared with the alloys alloyed with neodymium and erbium, the minimum oxidation rate was noted. The addition of 0.5 and 1.0 % Nd and Er in the zinc alloy Zn0.5Al significantly increases its oxidizability. Alloy additions (on 0.01÷0.05 %) of neodymium and erbium slightly increase the oxidizability of the eutectoid zinc alloy Zn0.5Al. During the oxidation of the studied hard alloys, protective oxides pellicle are formed ZnO, Al2O3, Nd2O3, Er2O3, ZnAl2O4.
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Effect of the carburizing layer on the morphology of chromium carbides
Статья научная
Low carbon steel substrates were face-hardened by cementing, after which thin layers of chromium were deposited electrolytically on these substrates. After deposition, the samples were exposed to isothermal annealing at a temperature of 950°C. The characterization of the thin layers was carried out by means of optical microscopy and interferometry using the Vickers micro- hardness test. The obtained results allowed establishing the phase shift kinetics (under the effect of the cementing layer) in thin layers of chromium, which are transformed into chromium carbide when passing through metastable transition phases. These transformations were due to diffusion of the carbon atoms coming from the layer of cementing, germination and growth in solid phase. This fact has been examined taking into account the annealing temperature, the lattice parameter evolution and the deposited chromium layer morphology. As to mechanical properties, it was established that the micro-hardness depends on the phase shift evolution.
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Статья научная
Slime processing at PD OAO MMC Norilsk Nickel involves oxidizing-sulphatizing roasting, calcine leaching with sulphate solution, calcine cake smelting into anodes followed by electrolytic dissolution, and a number of processes designed for accompanying elements recovery. Resulting final products are platinum-palladium (60-65 % Σ Pt+Pd) and rhodium-ruthenium (2.0-3.5 % Rh) concentrates (KP-1 and KP-2, respectively), refined silver, selenium of technical grade and tellurium. Process cycle duration, considerable work-in-process amount, a great number of operations and low efficiency of individual operations are considered to be disadvantages of the slimes processing method. We determined optimal process conditions for copper slimes calcine cake repulping with sulphate (reagents, consumption and sodium hypochlorite feed rate) offering 6-7 fold increase of Pt recovery into solution and 1,5-2,0 fold that of Pd. PGMs precipitation from resulting solutions was fount to yield precipitate with Pt and Pd content amounting up to 55 %; this makes it possible to produce it as final product. The product is then sent to a final product (KP-1 concentrate) packaging section bypassing smelting and electrolysis stages with inherent high PGMs losses, resource intensity and long duration time.
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Electrochemical method of discharged waters cleaning with of alternating current
Статья научная
High power consumption, equipment unhandiness, and need for consumable materials prevent wide introduction of electrochemical methods of water and water solutions cleaning. This article presents the results of tests of industrial discharged water cleaning applying electrochemical method and shows the mechanism of this process.
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