Статьи журнала - Журнал Сибирского федерального университета. Серия: Техника и технологии
Все статьи: 1367
Статья научная
The results of computer-aided design of deformed semi-finished products manufacturing technological processes for the jewelry chains from new alloys of precious metals production are presented. Algorithms and automated calculations adequacy confirmed by computer simulation and physical modeling of bar rolling and drawing processes. Using data on the mechanical properties of new gold, palladium and silver alloys, patented by the authors, the energy-power equipment load of the subject to the limitations on permissible rolling forces and torques are calculated.
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Concretion onyx of the Torgashino deposit – new type of carbonate vein onyx (Krasnoyarsk territory)
Статья научная
A new type of carbonate vein onyx is identified. The onyx composition is calcite. Banding is preconditioned by alternation of the zones of light calcite, and calcite rich in ferruginized argillisite. Three types of vein bodies are composed of poorly dislocated, brecciated and concretion onyx. The latter type is presented by easily dissected concretions (5-12 cm). Calcite crystal fragments (1-3 cm) overgrown by concentric-zonal ferruginized much argillisite-altered calcite onyx looking like “rounded pebble” (2-4 cm) from outside, overgrown in its turn by concentrically banded large radial-columnar calcite crystals form the concretions. Concretions are interesting in terms of collection material.
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Construction of geographic information system of corporate level in geological prospecting
Статья научная
The paper describes the experience of application of geographic information technologies and methods of processing of the Earth remote sensing data for solving practical tasks in the search for hydrocarbon deposits. The most important feature of technological processes in this sphere is the necessity to analyze large flows of spatially distributed data of different nature in real time. We propose a service-oriented approach to organize a geographic information system (GIS) in order to optimize the solution of tasks in nature management and exploration for oil and gas studies.
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Control of convective flows in liquid metal influenced by electromagnetic forces
Статья научная
During preparation of metal alloys stirring of the melt plays an important role in order to even its chemical composition and temperature in the whole bath volume. It is necessary to create specific convectional streams of metal in the bath for effective stirring. Based on the known analysis of selforganization of convectional streams in the liquid heated from beneath (Rayleigh-Bernard effect), the present article describes a MHD-stirrer which allows receive a similar pattern of streams in the molten melt by using electromagnetic force. We have considered stirring processes in the rectangular bath and a MHD-stirrer which allows increase efficiency and reduce energy costs on the alloy preparation process.
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Control of the shape of semiconductor crystals when growing in Czochralski method
Статья научная
A model of the formation temperature and the rate of withdrawal of semiconductor crystals when grown by the method of “Czochralski”, which allows you to control the shape of the crystals, providing a fl at solidifi cation front and getting a quality fi nished product.
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Статья научная
The analysis of the effect of systematic errors in pseudorange measurements on the accuracy of determination the coordinates in the plane of the horizon is presented. The criteria for selecting navigation satellites GLONASS are proposed to minimize the systematic components of the error of the planned coordinates, determined on the basis of the method of least squares. The results of checking the effect of selection of satellites when processing real pseudorange measurements by signals of the GLONASS system are presented.
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Cнижение оксидов азота в процессе сжигания Канско-Ачинских углей
Статья научная
Изучена возможность использования понятия эксергии для решения экологических проблем, связанных с совершенствованием процесса вихревого сжигания канско-ачинских углей с учетом снижения оксидов азота. Эксергия является единственным понятием в физике, определение которого включает в себя окружающую среду и особенности технической системы. Изложены мероприятия по снижению вредных выбросов с применением метода эксергии и аппарата неравновесной термодинамики для оценки их эффективности.
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Deep purification technogenic solutions of nickel ions (II) by the modified aluminosilicate
Статья научная
There studied an adsorption method for purifying technological solutions of nickel (II) ions modified aluminosilicates. The obtained adsorption isotherms. Experimental data were processed using the models of Langmuir, Freundlich, BET and Dubinin-Radushkevich. Defined constants for these equations. It is shown that the adsorption on aluminosilicates modified poly-1-vinylimidazole best describes the model of Freundlich the adsorption on aluminosilicates modified poly-4 vinylpyridine - Langmuir. The model of Dubinin-Radushkevich is used to calculate the free energy of adsorption. For all modified aluminosilicates, the value of free energy of adsorption, indicates an ion exchange mechanism, and fixation the ions of Nickel (II) has a chemical nature.
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Design of 2.4 GHz microwave bandpass filter
Статья научная
This paper presents in detail the design of highly selective microstrip bandpass filters that consist of microstrip open-loop resonators with a cross coupling that exhibit a single pair of attenuation poles at finite frequencies. The design approach enables one to use advanced full-wave EM simulators to complete the filter design, namely, to determine the physical dimensions of the filter. The results acquired through research & development process are simulated, analyzed and verified by using parallel-coupled lines filter topology, which are later, enhanced by various value-aided software tools such as MATLAB-7.0, CorelDraw-12, Microwave Office-2012.
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Статья научная
Now-a-days, increasing no. of incidents of vehicle theft have become a major problem in society. To prevent vehicle theft we can install an embedded system in the vehicle which takes care of this thing. In this paper, we deal with design of an embedded system to prevent vehicle theft. The pro-posed system makes use of AVR (Advanced Virtual RISC) microcontroller interfaced with a GSM module. After installing the system in the vehicle, if the vehicle is being stolen then the owner can control the ignition, say it to lock the vehicle or stop the engine by communicating with the GSM module from a mobile phone. The owner can bring back the vehicle to normal condition after enter-ing a secured password. Tracking of the vehicle is also possible due to the presence of SIM card in the GSM module. The system is designed in a single chip & the cost is very less.
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Design of pulse width modulation based dc motor for electric vehicle
Статья научная
The aim of this paper is to design and implement a power controller based on a microcontroller to be used in controlling a DC motor driving an electric vehicle. The ease of control and excellent performance of the DC motors ensure that it is widely used in many applications. This paper is mainly concerned on DC motor speed control system by using microcontroller PIC16F877A. Pulse Width Modulation (PWM) technique is used where its signal is generated in microcontroller. The program for PWM generation is written in C Language using MIKROC software. It is programmed into the microcontroller using Pickit 2. Then the microcontroller is installed into the motor control circuit. The Microcontroller acts as the motor speed controller in this paper. Based on the result, the readings are quite reliable. Through the paper, it can be concluded that microcontroller PIC16F877A can control motor speed at desired speed efficiently by using PWM signal.
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Статья научная
Potential productivity of agricultural crops can be evaluated using a new method based on chlorophyll photosynthetic potential (CPSP) derived from satellite information. The chlorophyll photosynthetic potential is determined by the amount of light absorbed by the plants in the region of the red band of chlorophyll absorption in a definite growth period. The value of parameter CPSP is determined as the area of the triangle whose vertex coordinates are exoatmospheric reflectance in the green, red, and near infrared bands and the respective mean wavelengths of bands. CPSPs of the crops have been examined using medium and high spatial resolution satellite (MODIS/Terra and Landsat7 ETM+) data obtained during the growing season of the plants. CPSP and crop productivity have been found to be interrelated. The obtained satellite evaluations are in good agreement with the ground-truth observation data.
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Determining hydraulic friction factor for pipeline systems
Статья научная
A comparative analysis of many well-known formulas for Darcy friction factor was carried out to determine accuracy and computational costs. To ensure a smooth transition from laminar fl ow to turbulent a cubic interpolation algorithm proposed to cover critical zone.
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Determining properties of a flow-through supercavitation desalination plant
Статья научная
Nowadays humanity faces an increasing problem of fresh water, the resource of which is rapidly declining because of anthropogenic activity. In this regard, the development of methods and means of purification of natural waters from various impurities, both solid and gaseous, becomes a priority. Steam extraction from the supercavitation cavity for its subsequent condensation is an obvious method of water desalination and has a number of undeniable advantages. However, numerous attempts to implement a method of cavitation desalination of water using large-scale setups have not been successful yet. The purpose of this study is to obtain experimental dependence between the temperature and flow velocity of the desalinated liquid, the pressure in the cavity and its size, the geometry of the streamlined body and the volume of steam taken from the cavity in the prototype of a supercavitation desalination plant. Analyzing obtained data made it possible to show a sharp difference between gas and steam cavitation, the performance of the experimental setup in the desalination mode has been determined. It was concluded that the steam velocity in the condensate extraction pipeline is a factor limiting the condensate output. Based on the data obtained, specific design criteria for industrial supercavitation desalination plants were determined.
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Статья научная
This article presents the results of mechanical tests of the properties of wire from alloys of Al-REM system obtained by methods of combined rolling-extruding and combined casting and rolling- extruding.
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Development and applications of MEMS components
Статья научная
This article provides the results of the MEMS (MicroElectroMechanical Systems) components studies. The design considerations and manufacturing techniques of the silicon-based MEMS components are considered. Results of the experimental characterization of the fabricated prototypes are provided. Furthermore, discussion related to the future development of the MEMS components is also presented.
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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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