Статьи журнала - Журнал Сибирского федерального университета. Серия: Техника и технологии
Все статьи: 1404
Compounding of spent nuclear fuel
Статья научная
The paper resents the results of the research into the processes of extraction of liquid radioactive waste of low and intermediate activity levels from storage and their hardening into inorganic binders (cementation process). The resulting cementing product has a number of advantages: it has high mechanical strength, is non-combustible, radiationally and chemically resistant, and has reduced external radiation of cementitious materials due to high density. Cementation as a technology of conditioning of liquid radioactive waste is a process of immobilization of liquid radioactive waste in cement matrix to obtain a solid fi nal product (cement compound). The paper shows the expediency of using the effects of cavitation technology which is quite easily feasible, energy-efficient, and in some cases has no alternative. The disposal of radiochemical production waste with the decommissioning of nuclear power plants on the basis of cavitation technology increases the productivity of their extraction and the strength of cement compound.
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Computational experiment in the problem of the recent traces of oceanic cosmic impacts
Статья научная
The paper aims to fill the gap between geological practice on the problem of the recent traces of oceanic cosmic impacts and computational experiment on tsunami geology problem. Computational experiment and numerical analysis data of the oceanic comet impacts could be more effective for mega tsunami understanding and prediction than the traditional geological methods. We explored the depositional traces of large-scale water impact on the coast and modeling of mega tsunami given the steep waves and Mach reflection on the rocky shore and described chevron dunes form on the base of neural network technology to solve the inverse tsunami problem. The ocean impact craters were explored using the wavelet analysis digital data of the ocean bottom.
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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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Conditions for conducting experimental studies on grain drying
Статья научная
This paper examines the effect of heater power, speed of drying agent (air), adjustable slit width and number of revolutions of drying drum on the drying efficiency of the device, the moisture content of the rice pile coming out of the drum, and the chatness of rice in the rice pile. In addition, showed the changes in the value of the heating power and the drying efficiency of the device. The change of the adjustable slot size of the drying drum and the drying efficiency of the device consist of determining the effect of the moisture content of the pile of rice coming out of the drum and the effect of rice chatnash in the pile of rice. The experimental rice drying device in a stationary version was prepared at the “Andijan experimental-testing plant” JSC according to the design drawings developed by the Andijan Institute of Mechanical Engineering. Based on the results of theoretical studies, a drying drum with a diameter of 880 mm and a length of 1800 mm was adopted as the main working body.
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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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Статья научная
The article presents the results of the research of the cutting process of complex contour products from cellular honeycomb structures based on aluminum alloys, with a cutting tool in the form of a thin narrow blade with double-sided sharpening, reciprocating perpendicular to the wall of the honeycomb structure. The functional dependence of the cutting force and speed on the sharpening angle of the cutting tool blade and its thickness has been established. The optimal distance of the cut plane from the nodal points of the honeycomb structure is determined. The results of numerical simulation and experimental research to determine the optimal processing parameters that ensure the maximum cutting quality are presented. The reliability of the results obtained at the stage of analytical calculations and numerical simulation was confirmed experimentally by full-scale tests. As a result of the research, the optimal parameters and conditions of the cutting process were established: the thickness of the cutting tool is 0.4 mm, the sharpening angle is 20°, the speed of the tool is 5 m/s, the distance of the cut plane from the nodal point is 0.4 of the length of the cell wall. The results of the research can be used in the creation of a fundamentally new technological equipment for processing honeycomb cellular fillers, which have low manufacturability with traditional types of processing, which has found wide application in aviation and space production and makes it possible to produce complex-contour products from cellular honeycomb structures based on aluminum alloys. without additional processing, which increases its speed and reduces the cost.
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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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