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Date submitted2017-11-16
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Date accepted2018-01-16
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Date published2018-04-25
Volume and surface distribution of radiation defect in natural diamonds
- Authors:
- E. A. Vasilev
- A. V. Kozlov
- V. A. Petrovskii
In the following article, we have studied the variations of natural irradiation of diamond crystals. The natural diamonds in some cases show homogeneous green colour, caused by irradiation of the entire crystals volume. Radiation damage effects, produced by the low-radiation doses, are detected by the luminescence of the GR1 system. The high-radiation doses cause bluish hue, turning into a greenish colour, while the maximum level of volume irradiation produces the black crystals. The crystals with homogeneous volumetric black colour distribution were also studied. The major source of radiation in such cases may represent a local stream containing water rich in 222 Rn and its decay products. There is a review of the geological environment in which diamonds could be irradiated due to the decay of the 222 Rn containing in water.
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Date submitted2017-11-09
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Date accepted2017-12-28
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Date published2018-04-25
Chemical weathering of lower paleozoic black shales of south Sweden
- Authors:
- D. O. Voronin
- E. G. Panova
Lower Paleozoic black shales are widespread in Sweden and form part of the Baltic paleobasin, which deposits are also known in Estonia and the Leningrad Oblast of Russia. These rocks are enriched in a carbon substance and characterized by the significant content of uranium, vanadium, molybdenum, copper, nickel, cobalt, zinc, and lead. Black shales contain high levels of Sr – 968; Ba – 337; U – 229; V – 509; Mo – 165; Zn – 411; Ni – 214; Cu – 112 (ppm) in secondary minerals composition formed on their surface. Retrograde diagenetic conditions facilitate the black shales chemical weathering. Elements of the first (U), second (Mo, Sr, Zn), and third (V) hazard classes are washed out of black shales and secondary minerals and can further enter biological cycles.
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Date submitted2017-10-27
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Date accepted2018-01-01
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Date published2018-04-25
Method of induction control of iron weight fraction in magnetite ore
- Authors:
- I. N. Bazhenov
- O. O. Basov
This paper analyzes the peculiarities of existing methods and means of induction control of magnetic susceptibility of the medium are analyzed. It is concluded that these means have a common drawback due to the low measurement accuracy caused by the wave-like dependence of the instrument sensitivity on the gap between the probe and the medium surface. The ways of increasing the instrument sensitivity and measurement accuracy of controlled parameters by means of inductive measuring transducers are revealed. A method for induction resonance control of iron weight fraction in magnetite ore has been developed, and its effectiveness has been estimated using simulation modeling. Practical recommendations for the development of quality control instruments for magnetite ores have been developed. A variant of the quality control unit layout for working with magnetite ores is proposed.
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Date submitted2017-11-12
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Date accepted2018-01-23
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Date published2018-04-25
Metallurgists of the Mining university and development of monetary industry. 245 years of history
Monetary industry combines several stages of metallurgical processes, which are continuously improved with the development of technology and the level of knowledge in the field of non-ferrous metals. The graduates of the Mining Institute, metallurgists of several generations, took part in establishment the Mint and development of technology to produce coins. Since January 24, 1718, when Peter the Great signed the decree «on production of small and large coins ...», the history of the monetary system of Russia and the coining of the first silver rubles began, which subsequently formed the basis of money relations. Twenty-four graduates of the mining and metallurgical departments of the Mining University worked as heads and münzmeister of the Mint. Silver rubles and work of Russian münzmeisters provided financial stability in Tsarist Russia from 1718 to 1917 and laid the foundation for further development of the monetary industry, taking into account new knowledge in the field of enrichment, preparation of polymetallic ores and their melting, and also stamping and processing of precious metals. This is the history of Russia and St. Petersburg, it combined the history of the Mining University, which this year will be 245 years old. It is of scientific interest to restore historical justice and update the methodological knowledge in the field of technology of monetary industry and metallurgical processes.
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Date submitted2017-10-31
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Date accepted2018-01-01
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Date published2018-04-25
Peculiarities of formation and growth of nanodispersed intermetallic strengthening inclusions in rapidly-solidified alloys of Al–Mg–Zr–X-system
- Authors:
- D. I. Budelovskii
- S. Yu. Petrovich
- V. A. Lipin
The paper is devoted to the influence of the fourth element on the microstructure of the rapidly-solidified alloys of the Al–Mg–Zr-system. Alloys were additionally doped with high-melting-point metals Ti, Hf, W, and Nb. In the structure of all samples in the immediate area of the cooled surface, uniformly distributed intermetallic inclusions of several nanometers in size were detected. Such a structure can be represented as a dispersion-strengthened composite. A quantitative metallographic analysis was carried out to quantitatively describe the structure of the obtained particles of the cooled melt. The obtained rapidly-solidified alloys can be described as dispersion-strengthened composite materials with the aluminum-magnesium alloy matrix and the intermetallic particles strengthener. Depending on the alloying component, these particles differ in shape (spheres, plates, agglomerates) and in size (from 200 nm when alloying with Hf and W up to 1.2-1.5 μm with Ti and Nb alloying). The X-ray phase analysis (XPA) showed that in the studied alloys of the Al–5Mg–1.2Zr–(0.5÷2.0)X-system, high cooling rates of melts lead to the formation of new intermetallic compounds that are absent in equilibrium systems. The example of an alloy with hafnium additive shows that an increase in the content of the alloying component (from 0.5 to 2 % by mass) leads to an increase in the volume ratio of intermetallic inclusions (from 5 to 12.8 %). At the same time, their shape and average size remain unchanged. The additional alloying component will improve the mechanical characteristics of aluminum alloys by increasing the recrystallization threshold of a rapidly-solidified alloy.
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Date submitted2017-11-15
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Date accepted2018-01-13
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Date published2018-04-25
Use of nano-dimensional hydrophobic coatings for obtaining electrets based on silicon dioxide
- Authors:
- N. S. Pshchelko
The article considers the physical-technological foundations of formation of the silicon dioxide (SiO 2 ) based electret for use in devices of MEMS technology. Studies have shown that the best electret properties are in SiO 2 obtained in «wet» oxygen medium as compared to samples obtained by other oxidation methods. This is probably due to the large number of Si-OH groups on the surface of the oxide in the «wet» SiO 2 , which increases the effectiveness of the hydrophobic coatings during the modification of the SiO 2 surface. It has been found that other methods of obtaining oxide, for example, electrochemical or plasmachemical, do not make it possible to obtain SiO 2 with good electret properties. The decrease of the charge injected into an electret can occur due to the presence of volume or surface conductivity, as well as the screening of this charge by opposite charges from the medium, leading to significant decrease of electret surface potential at high ambient humidity. To increase the stability of the electret effect, it is necessary to perform water-repellency treatment of SiO 2 surface by applying thin (nanosized) water-repellent coatings. Experimental results on the stability of the electret surface potential are presented for usage of various water repellents. The most promising water repellents are high-temperature photoresist FPT-1-40 and polyimide nanolayer compositions – Langmuir-Blodgett films.
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Date submitted2017-10-26
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Date accepted2017-12-25
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Date published2018-04-25
Conditions of austenite diffusional transformation in steel of Cr–3Ni–Mo–V-composition with high austenite stability
- Authors:
- V. V. Tsukanov
- N. V. Lebedeva
- Yu. M. Markova
The paper investigated the bainitic steel of 10KHN3MFA grade, which is characterized by the increased tendency to display structural heredity in the forgings with large cross-sections. The samples have been studied for kinetics of diffusional transformation process both under continuous cooling and isothermal conditions, as well as its microstructure. It is determined that in the range of subcritical temperatures with cooling from 900 °C in the studied steel, the initial stage of separation of the ferrite phase takes place. It is shown for the first time that the diffusional ferrite-pearlite transformation fades. Previously it was believed that the beginning of transformation under isothermal conditions proceeds to the end. It was found out that the transformation begins immediately after the beginning of isothermal holding, without the generally accepted incubation period.
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Date submitted2017-11-20
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Date accepted2018-01-09
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Date published2018-04-25
Sulfidization of silver-polymetallic ores of «Goltsovoe» deposit for decreasing loss of silver in mill tailings
- Authors:
- L. V. Shumilova
- O. S. Kostikova
The results of laboratory studies of flotation concentration of silver-polymetallic ores of the Goltsovoe deposit at the Omsukchansk concentrator are presented. The results of sieve analysis of mill tailings of the experimental sample of MTP N 101 (N 7577-i) are described. They indicate that a large amount of silver (123 g/t) is lost in the size class – 0.040 mm (yield 50.25 %). According to the results of mineralogical analysis, it is established that the major losses of noble metal are associated with its fine impregnation in oxides, sulfides and silicate rocks. The main silver-bearing minerals are acanthite, polybasite and kustelite (class – 0.040 mm). Experimental studies were carried out in two stages. The purpose of the first stage is to determine the influence of grinding fineness in flotation feed (for a finished class content of 0.074 mm in the range of 60-95 %) for silver recovery at different amounts of butyl potassium xanthate (50, 150, 300 g/t). The purpose of the second stage is to evaluate the effectiveness of sulfidization at different consumption of sodium sulfide Na 2 S·9H 2 O (50, 150, 200, 450, 750 g/t – 1 % aqueous solution) under the conditions of the optimal reagent mode established in the first stage of the study. The results of experiments to determine the optimum grinding fineness and studies on the enrichment of silver-polymetallic ore with the use of sodium sulfide as a sulfidizer are presented. The efficiency of the sulfidization process is estimated. The following experimental dependencies of silver recovery are established: on the degree of grinding and consumption of butyl potassium xanthate; on variations of grinding fineness and the consumption of sodium sulphide (with a consumption of butyl xanthate 150 g/t); and on grinding fineness at optimum consumption of sodium sulfide 150 g/t and butyl potassium xanthate 300 g/t. A comparative evaluation of dependence of silver recovery index from the degree of grinding fineness before and after introduction of sodium sulphide (collecting agent consumption of 150 g/t) is given. The mathematical models describing the dependence of silverrecovery on technological parameters, allowing to control the process of flotation of refractory ore with a large number of primary sludges and the tendency of sludging during grinding and concentration (secondary sludges) are given. The optimal consumption of flotation reagents has been experimentally established: sodium sulfide 150 g/t, butyl potassium xanthate 300 g/t with rational grinding (the content of the finished class is 0.074 mm in the flotation feed 85-95 %). Absolute recovery of silver from the ore of the silver-polymetallic deposit «Goltsovoe» in comparison with the technological indicators of the Omsukchansk concentrator processing the material in accordance with the standard mode, increased by 14.1 % (from 70.7 to 84.8 %) with the yield 9.09 % due to intensification of recovery of silver-bearing semi-oxidized sulphides with reduced flotation activity and compensation of high absorptive capacity of fine particles. The amount of silver in the size class – 0.040 mm in the sample MTB N 101 (N 7698-i) after the use of sulfidization was 83 g/t at the yield of 72.01 %, which indicates the efficiency of the process. The losses of silver in mill tailings decreased by 40 g/t (32.52 %). This proves the possibility of processing silver-polymetallic ores of the Goltsovoye deposit without reclaimer operation.
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Date submitted2017-11-23
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Date accepted2018-01-19
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Date published2018-04-25
Theoretical aspects of the technical level estimation of electrical engineering complexes
- Authors:
- S. V. Kolesnichenko
- O. V. Afanaseva
The results of the analysis of methods allowing to evaluate the technical level of the electro technical complex (ETC) are presented and an original technique based on the application of the integral indicator is presented. The characteristic of each stage of the technique is given. The proposed scientific and methodological apparatus for assessing the technical level of the ETС is illustrated by the examples of the executive elements of the ETC comparison (internal combustion engines) using an integral quality index that links both the main characteristics of the samples and the means spent for achieving them. The proposed approach for assessing the technical level and quality of the ETC on the basis of an integral indicator should be carried out already at early stages of the life cycle when solving the following problems: the rationale for the economic feasibility of developing new or improving the quality of the produced ETCs; choice of the best option for the developed ETC; justification of requirements for the ETC; decision-making on the establishment and removal of ETC from production; substantiation of the rules of operation of the ETC in various conditions.
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Date submitted2017-11-17
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Date accepted2018-01-05
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Date published2018-04-25
Estimation of the relation of strength and ultrasound speed in glass-reinforce plastic
- Authors:
- A. I. Potapov
In mining machinery, details and products made of composite materials are widely used, especially from GRP (glass-reinforce plastic). The work evaluates the relationship between the strength and the speed of ultrasound for nondestructive testing of strength in an article made of composite materials such as GDR with the use of a pulsed ultrasonic method. Methods for estimating the connection, the method of mechanical compression tests and mathematical processing and establishing the relationship between the ultrasonic velocity and the strength of GRP are considered. The results of experimental studies on establishing the relationship between the strength of GRP on compression and the speed of longitudinal ultrasonic waves are presented. As a result of statistical processing of the experimental results, equations of the relationship between the compressive strength and the ultrasonic velocity in fiberglass are obtained.
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Date submitted2017-10-25
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Date accepted2018-01-17
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Date published2018-04-25
Innovative technology of large-size products manufacture
- Authors:
- S. N. Sanin
- N. A. Pelipenko
Advantages and prospects for the use of mobile robotic machine-tools in the manufacture of large parts in the mining, cement and nuclear industries are considered, as well as the importance of using welded structures to reduce production costs. Schemes for finishing mechanical machining of welded large-sized parts such as bodies of revolution with the use of mobile robotic machine-tools equipped with a belt-grinding tool, an enlarged description of the technological process for manufacturing a large-sized shell of a welded structure are presented. The conclusion is made that it is necessary to take into consideration the use in the industry of frameless production technology, especially for the machining of large-sized parts, and the use of small mobile robotic machine-tools is a productive approach and has a prospective character. The technological approaches proposed in the article make it possible to remove the restriction on the overall size and mass of the parts being manufactured, which are proposed to be manufactured directly at the site of future operation. The effectiveness of this technology is confirmed both by theoretical research and by practical data of the authors. It was noted that the production by the domestic machine-tool industry of mobile universal and special robotic machine-tools will allow the country's engineering industry to be brought to a new, high-quality world level.
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Date submitted2017-10-29
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Date accepted2017-12-31
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Date published2018-04-25
Risk assessment of accidents due to natural factors at the Pascuales – Cuenca multiple-use pipeline (Ecuador)
- Authors:
- Dzh. Zambrano
- S. V. Kovshov
- E. A. Lyubin
The natural aspects of the accident risk at the Pascuales – Cuenca multiple-use pipeline (Ecuador) are analysed in the paper. The Russian Methodological recommendations for the quantitative analysis of accident risks at hazardous production plants of oil trunk pipelines and oil product trunk pipelines issued in 2016 are used as a methodological framework due to relatively poorly defined evaluation mechanism for natural factors of accidents at oil trunk pipelines in the most widespread international accident risk assessment methodologies. The methodological recommendations were updated to meet the environmental conditions of oil pipelines of Latin America. It was found that the accidents due to natural factors make up approximately 15 % of cases at oil trunk pipelines in Ecuador. Natural geographical features of the areas surrounding the main Ecuadorian Pascuales–Cuenca oil trunk pipeline and its relatively short length allow defining three zones along the line in terms of the accident risk: lowland coastlines, high plateaus, and foothills. Calculations and analysis revealed that the maximum predicted specific frequency of accidents is characteristic of the lowland seaside area. The evidence showed that physical and chemical properties of soils and significant seismic activity are the root causes of failures.
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Date submitted2017-11-22
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Date accepted2018-01-04
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Date published2018-04-25
Justification of a methodical approach of aerologic evaluation of methane hazard in development workings at mines of Vietnam
- Authors:
- V. V. Smirnyakov
- Nguen Min' Fen
The methods of evaluation of the aerological conditions to be performed for the purpose of normalization of mining conditions are provided in the present review; the location of possible accumulations of explosive gases during the drift of the development workings are taken into account. To increase the safety of the development working regarding the gas factor, a complex evaluation of a working was developed with respect to the dynamics of methane emission and air coursing along the working which is strongly affected by the character of the leakages from the ventilation ducting. Thereby, there occurs a necessity of the enhancement of a methodical approach of calculation of ventilation of a working which consists in taking into consideration a total aerodynamic resistance of the booster fan including the local resistances of the zones of the working. An integer simulation of the gas-air flows realized on the basis of a software package FLowVision allows to evaluate a change in the methane concentration in the zones of local accumulations.
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Date submitted2017-11-06
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Date accepted2018-01-12
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Date published2018-04-25
Improvement of the procedure of recruitment of personnel for hazardous work environment
- Authors:
- N. D. Tskhadaya
- D. Yu. Zakharov
With the purpose of the reduction of the number of the emergency and abnormal situations in the oil mines conditioned by the influence of the «human factor» an opportunity of application of the system of permit to the works with respect to the real functional state of the personnel is considered in the paper. A «human factor» may become a reason not only for the occurrence but also for the development of the emergency situation according to the unfavorable scenario. The arduous labor conditions such as heating environment, low level of lighting, high level of the dust load may result in the multiple increase of the negative influence of the factors of the real functional state on the quality and safety of the operations. Reasoning from this fact, the consideration of the factors of the functional state in the process of getting a permit to works in the oil mines is of vital importance and requires a well-reasoned and integrated assessment. Having highlighted the parameters of the real functional state and evaluated them on the basis of the validated psychophysiological tests the authors managed to join them together into a method of the evaluation of the influence of the functional state of a person on the process of making executive decisions in the emergency situations. When using the developed method, an opportunity of the enhancement of the system of professional recruitment and a process of getting a permit to the hazardous operations for both the supervising manpower and the operation personnel occurs. The method draws on the considerable volume of the applied experimental studies which were pursued on the basis of the facilities of the oil and gas complex. The data obtained allow to make conclusions about the feasibility of an insert new criteria of the evaluation of the readiness of a person to perform the job responsibilities. Applying the obtained criteria makes possible to create measures for the psychological adaptation of the personnel, for the improvement of the labor discipline, for the increase of the safety of operations in the unique Yarega oil mines.
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Date submitted2017-11-08
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Date accepted2018-01-20
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Date published2018-04-25
Major trends in efficiency upgrading of the economic activity in the Arctic zone of Russian Federation
Organization of efficient economic activity in the Arctic zone requires development of human potential, transport infrastructure, exploitation of natural resources under the conditions of greatest possible environmental safety. In order to choose preferable trends of economic development and to provide efficiency of operations in the Arctic zone it is crucial to perform research in the areas of industrial efficiency upgrading and rational use of fuel, energy, mineral, chemical and biological resources of the Ocean and littoral areas of Russian Arctic. The paper analyzes major trends in the research on increasing economic efficiency of operations aimed at territory development in the Arctic zone. The authors justify the need to examine economic problems of rational resource use in the Arctic zone of Russia based on the proposed system of resource-estimation indicators and their application in establishing a mechanism of rational resource use with a due regard to protection of the marine environment. The paper also focuses on methodological problems of the target programme approach to complex development of the Arctic zone, creation of target programmes, industrial development and rational use of natural resources. The authors give rationale for the key task in this area – development of methodological principles of forming federal and regional target programmes, aimed at exploration, exploitation and rational use of natural resources in the Arctic zone of Russian Federation. An analysis is provided that focuses on the problems of creating a scientifically justified hierarchical system of programmes and regional regulations, creation of a scientific information data bank and other methodological issues.
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Date submitted2017-11-09
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Date accepted2018-01-02
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Date published2018-04-25
Analyis of government support tools for mining companies in the Russian Arctic zone
The paper focuses on the development of mining companies in the Russian Arctic zone in the context of searching for new ways to improve government control over the development of the Arctic zone. Existing outer restrictions imposed upon Russia and changes in the global financial market not only determined a paradigm shift to regional government control, but also dictated the need to search for new mechanisms of state influence on the regional economy. Primarily it concerns the development of growth zones based on utilizing resource potential, creation and implementation of tools aimed at attracting investments to the Arctic zone and offsetting the factors of northern appreciation for mining companies. With this in mind, government support of specific regional development projects is becoming an urgent issue. The authors analyze new approaches to the development of public management in the Russian Arctic zone, for mining companies in particular, aimed at creating special economic conditions that would stimulate the operation of plants extracting mineral resources. Research methodology is based upon the analysis of factors restricting economic development and growth of the Russian Arctic zone and mining companies in the first place, as well as analysis of possible tools to support mining plants operating in the Arctic territories (advanced development zones, industrial clusters, «supporting zones»). The authors define priority goals and prospects of implementing such operation mode for mining companies in the Arctic zone, and propose a list of possible measures of government support needed to stimulate development of mining companies and the entire Arctic economy of Russia.