Статьи журнала - Журнал Сибирского федерального университета. Серия: Техника и технологии
Все статьи: 1367
Prerequisites of gold-mining cluster formation in Russia
Статья научная
The article is devoted to the analysis of geographical, geological, technological and economic prerequisites of creation of a gold mining cluster in Russia as one of the organizational forms promoting consolidation of material, financial and personnel resources for implementation of technological innovations, in particular preliminary beneficiation in the developed modern conditions.
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Prerequisites to development of reduction process in heavy non-ferrous metal metallurgy
Статья научная
Essence of upgrading to process heavy non-ferrous metal sulfide concentrates and of reduction operations has been analyzed. Their environmental hazards have been shown. A landmark solution for metal reduction immediately from sulfi de compounds is proposed.
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Статья научная
In this paper the methodology of preventive control on hydropower plant is considered. Object of control – operationa l conditio n o f hydr o aggregates, bloc k transformer s an d flowin g pat h o f hydr o power station. In article possibility of creation on the basis of the given methodology of a decision-making support subsystem is considered. The given subsystem will allow operation personnel to obtain the data about an equipment condition in the form convenient for perception and to make correction or change of an operating mode of the given equipment for the purpose of prevention of damage and maintenance of station normal work.
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Process development for refractory gold concentrates treatment on Pokrovsky pox hub
Статья научная
The chemical composition and mineralogy of Malomir and Pioneer gold-bearing ores were discussed. The main gold forms in the ores were indicated: the preferential gold association with sulfide minerals was noted. The chemical composition of sulfide flotation concentrates was shown. The laboratory and pilot tests results of concentrates pressure oxidation were introduced. The influence of organic carbon content in the concentrate and chloride ion content in the liquid phase of pressure oxidation slurry on the gold extraction from materials were noted and researched. The effect of preliminary treatment stages on POX indicators was shown. The positive effect of hot autoclave slurry conditioning on gold recovery was noted. The process flow sheet for treating both Malomir and Pioneer ores was developed and advised.
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Process modelling and optimization of green lube oil synthesis
Статья научная
Modeling and optimization of trans-esterification of palm kernel oil (PKO) to trimethylolpropone ester (TMP ester- a bio-lubricant) via palm kernel oil methyl ester (PKOME-a biodiesel) synthesis were investigated. The central composite design (CCD) component of the response surface methodology (RSM) was adopted for the optimization of the process parameters, where temperature and weight ratio of PKOME to TMP were held constant at 130 °C and 3.9 : 1 respectively, to generate 20 experimental runs. Bio-lubricant yield was calculated for each experimental run. A quadratic-like model was generated that related the yield to the process parameters (Reaction time, Stirring Speed, and Catalyst concentration). The predicted and actual R2 value were 0.9856 and 0.9959 respectively, which indicate an excellent agreement between experimental and predicted bio-lubricant yield. The predicted maximum bio-lubricant yield was 98.11 % at reaction time of 99.9084 mins, stirring speed of 863.794 rpm, and catalyst concentration 0.84522 wt. %. The experimental value obtained under same conditions was 96.996 %. Physico-chemical analysis of the bio-lubricant synthesized at optimum conditions were found to be within the range of the ASTM standard for bio-lubricants.
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Processing of SAR amplitude images with posting the results on web server
Статья научная
The paper presents the processing and analysis of COSMO-SkyMED and Sentinel-1A amplitude images using texture analysis, image classification, composite images, and interpretation. It also describes the method of visualization the remote sensing data by placing it in analytical information system «RegionView».
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Статья научная
The use of remote sensing data based on specialized algorithms for processing of thermal images of Earth’s surface in conjunction with the geological and geophysical data simplifies the allocation of oil-bearing geological structures.
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Production of carbon briquetted fuel from the coals of Kansk-Achinsk basin by means of hot pressing
Статья научная
The paper presents the results of the research on thermobriquetting of dense brown and gaseous coals from Kansk-Achinsk basin, brown and gaseous coal mixtures with no binding agent as well as a mixture of brown coal with hydrolyzed lignin as a binding agent. The heating values of the products were shown to increase 1,3-1,5 times in comparison with the raw coals аnd the volatile yields causing black smoke decrease by 11-13 %. Most efficient, strong moistureproof briquettes with the heating value of 25,50 МJ/kg were produced of the mixture of the B3 brown and gaseous coals. The addition of lignin to the brown coal allowed lowering the pressing temperature from 380-400 оC to 200-250 оC, thus improving the reliability of the press operation.
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Статья научная
The consideration was given to a transition to medium thickness slabs for complexes CCM-Plate Mill and CCM-Hot Rolling Mill. We used two examples, considering their technical characteristics, to show possible advantages and disadvantages. From the point of view of energy efficiency, we proposed a number of measures for a perspective application of this transition.
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Статья научная
Rare and new minerals (tashelgite, mukhinite, hibonite, goldmanite and others) discovered in the process of geological studies of the 20th and the 21st centuries in the carbonate stratum of the Tashelga polymetamorphic complex (R3-Rz3ts) composing the graben-syncline structure within the Kuznetsk- Alatau shear zone in Gornaya Shoriya are described. It is shown that the unique mineralization of skarnoids, calciphyres and metasomatites of the district is preconditioned by the processes of metamorphism and further metasomatosis of original carbonate marine sediments contaminated by laterite metabasite weathering products. The impact of the basic rock chemistry on the whole further polychronic endogenous rock mineralization is traced even in such relatively closed systems of the zone as granite pegmatites.
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Recognition of forest species and ages using algorithms based on error-correcting output codes
Статья научная
The basic model of the recognition of forest inventory characteristics using spectral features is represented in the framework of the problem of hyperspectral airborne imagery processing. The algorithm of multiclass supervised classification based on the error-correcting output codes underlies this model. The support vector machine method is used as the necessary binary classifier. The method of the construction of training set by using mixed forest plots is represented. Results of the retrieval of species and age composition of forest stands from hyperspectral images are represented for the selected test area. The estimate of accuracy of the retrieval of the mixed forest composition is comparable with the accuracy of ground-based forest inventory data.
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Recycling carbonaceous materials by cavitation nanotechnology techniques
Статья научная
The purpose of this paper was the studying of hydrodynamic cavitation effect on physical properties of carbonaceous material - heat-treated cellulose. The heat-treated cellulose powders have been investigated by the method of X-ray phase analysis (XPA). Hence it was possible to obtain nanofluid - a water suspension with the features characteristic of weak water suspension of fulleroids as a result of rather short cavitation processing of the weak water suspension of heat-treated cellulose, nanofluid is very perspective for industrial technologies.
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Статья научная
Regional scientific-technical organization plays an important role in the expansion of the sphere of information technologies in the economy of the Krasnoyarsk region. This paper deals with the aspects of interaction between the state and regional structures involved in the telecommunications business.
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Regularities of formation of the ordered structures in molybdenum at ion implantation
Статья научная
Is shown, that the character of structural-phase transformations in molybdenum at ion implantation by the elements of the interstitial phase is defined, in the main, by the size factor, i.e. by the ratio of the atomic sizes of implanted elements and atoms of metal. The researches are carried out on molybdenum monocrystals at implantation by ions of Ar, C, N, O, B, Si, P, S.
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Regularities of formation of the ordered structures in refractory metals at ion implantation
Статья научная
Is shown, that the character of structural - phase transformations in tungsten and tantalum at ion implantation by the elements of the interstitial phase is defined, in the main, by the size factor, i.e. by the ratio of the atomic sizes of implanted elements and atoms of metal. The researches are carried out on tungsten and tantalum monocrystals at implantation by ions of, N, O, P.
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Статья научная
The purpose of this study was a comparative study of seasonal dynamics of chlorophyll potential, leaf area index and fresh biomass of different varieties of wheat based on refl ectance spectra obtained by ground-based remote measurements. The study reports data on seasonal dynamics of refl ectance of wheat canopies composed of various wheat cultivars in the Krasnoyarskii Krai. The study presents an optical remote method for determining chlorophyll potential, S(t), of wheat plants, which is calculated based on reflectance spectra of the crops during the growing season. Chlorophyll potential of wheat plants, S(t), may serve as an indicator of their physiological state and potential biological productivity; also, it can be used to predict grain yield of wheat fields. Different wheat cultivars have different chlorophyll potentials, S(t), during the growing season. There is high positive correlation between dry and fresh wheat biomass, and chlorophyll potential, S(t), of wheat plants. A digital database has been compiled, which contains spectral data of the wheat canopies studied.
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Reliability evaluation method of the wind-diesel installation with application of dynamic fault tree
Статья научная
Renewable energy sources becoming more widespread in decentralized power supply systems. However their functioning depends on the natural resources potential having variable character. This dependence influences reliable work of autonomous power supply system. Reliability analysis of a renewable energy based autonomous generating system is the actual practical task requiring the solution. For the reliability assessment of autonomous wind-diesel installation it is offered to use the method of dynamic fault tree with Markov models for representation of dynamic operators. The offered method is applied for reliability calculation of the wind-diesel installation functioning in the autonomous power supply system in the north of Krasnoyarsk region.
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Статья научная
This article represent the results of research of mechanical and electrical properties of deformed semi-fifnished products from alloys system Al-Zr, obtained with using methods of combined casting-rolling, combined casting and rolling-extruding and drawing.
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Статья научная
This article examines the issues of hydraulic resistance of solar air heaters with concave tubes and reduction of pressure losses, as well as the determination of the air flow in concave tubes installed in the working chamber of the solar air heater and discusses the reduction of the number of common tubes to reduce pressure losses in the solar air heater and the installation of concave pipes to give air a swirling motion to eliminate a sharp decrease in the heat transfer process.
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Статья научная
Satellite-to-ground optical communication link bit error rate (BER) depending on atmospheric propagation, pointing errors is considered. The theoretical and numerical estimations of BER for GEO to Earth link under various conditions are proposed.
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