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INFLUENCE OF THE TYPE OF DONOR CHARGES ON THE DETONATION RATE OF LOW-SENSITIVITY EXPLOSIVES

V. A. Belin, Z. G. Mollova

The article discusses the creation, testing and implementation of new donor charges designed to initiate low-sensitivity explosives. The cast booster donor charges are made entirely of explosives obtained from the disposal of unnecessary ammunition – TNT, RDX and TEN. The donor charges differ from the mass-produced ones, and have a mass of 150 to 900 g. They also have high explosive characteristics: velocity of detonation from 7200 to 7500 m/s, density of 1.6 g/cm3, excellent water resistance and strength. Their initiating ability on low-sensitivity explosives is significantly better than the one of TNT presses. The velocity of detonation of the main charge of a low-sensitivity emulsion explosive initiated with a cast booster is up to 700 m/s higher than when initiated with a TNT presses. It is especially important when building objects in the constrained conditions, at development of mountain territories for decrease in action of shock air waves and elimination of possibility of mountain collapses and landslides In article advantage of use of cast intermediate detonators on safety of explosive works is proved at development of mountain territories. The new design allows an increase in the security of initiating the charges in the boreholes, which allows them to be initiated with two detonators simultaneously.

Number of views: 271

COMPARISON OF THE CRUSHED MATERIAL MOVEMENT MODEL IN THE BODY OF A VERTICAL CENTRIFUGAL MILL

David G. Minasyan, Alana S. Eloeva, Sergey G. Nazarov, Pavel A. Skvortsov

Introduction. Improving the performance, increasing productivity, reducing the metal consumption of grinding equipment and other mining machines is usually a very expensive process. It requires a large amount of development work, the production of prototype machines, and a large amount of experimental research. In this regard, one of the most important tasks is to simulate the movement of bulk material in operations for processing minerals in various equipment. In such modeling, the discrete element method (DEM) is widely used. The purpose of the research is to compare the models of the movement of the crushed material in the body of a vertical centrifugal mill.
Research methodology The motion of the bulk medium in a vertical centrifugal mill was modeled using two models. In the first model, the cylindrical body of the centrifugal mill was assumed to be stationary, and on its surface and on the entire surface of the rotor, conditions were set for the absence of a relative speed of movement of the crushed material. In the second model, a hydrodynamic model was used to describe the motion of a granular material as a viscous incompressible liquid with a compression ratio that depends on the pres-sure. In this model, the viscosity coefficient is represented as consisting of two terms: a constant (analogous to dynamic viscosity) and an excess pressure over hydrostatic pressure.
Research results It is established that both models give the same character of the movement of the material in the mill body. It is determined that the absolute velocity of the material movement near the walls and near the mill rotor is approximately the same for both models, but in the data obtained using the hydrodynamic model, as the material moves away from the walls and the rotor, it slows down more than for the model using the discrete element method. It is revealed that the absolute velocity of the material movement near the walls and at the axis of the mill rotor is approximately the same for both models, but in the data obtained using the hydrodynamic model, as it moves away from the walls and the rotor, the material slows down significantly more than for the model using the discrete element method.
Based on the simulation results, it can be concluded that for a more accurate simulation of the processes occurring during the rapid movement of bulk material in the grinding equipment, it is preferable to use a model using the discrete element method. It is advisable to use the hydrodynamic model for conducting a large number of search dawns or as a predicate model that will allow you to quickly set the initial velocity values for particles in a model using the discrete element method.
Conclusions 1. A hydrodynamic model of the motion of a bulk medium in a vertical centrifugal mill, represented as a viscous incompressible liquid with a compression coefficient depending on the pressure has been developed. 2. It is established that for a more correct simulation of the processes occurring during the rapid movement of bulk material in the grinding equipment, it is preferable to use a model using the discrete element method. At the same time, it is advisable to use the hydrodynamic model for conducting a large number of search calculations or as a predicate model that will allow you to quickly set the initial velocity values for particles in a model using the discrete element method.

Number of views: 237

PREDICTING THE STATE OF THE ICE BARRIER OF A VERTICAL MINE SHAFT UNDER ARTIFICIAL THAWING

Alexandra V. Kuzina, Vera N. Krynkina, Anatoliy A. Mishedchenko

At the end of the shaft penetration under the protection of the ice barrier and the termination of the process of freezing the rocks, the transition period from freezing to thawing begins. First of all, the tubing support of the trunk and the layer of rocks adjacent to the concrete support are subjected to thawing. At this time, water is pumped through the grouting holes in the tubing to check the tightness of the tubing column, after which the grouting is performed with cement mortar of the fixed space. Thus, grouting is an integral part of the work on waterproofing the support. For successful work on grouting, it is necessary to ensure the thawing of the ice barrier by a value of 1 m from the contour of the trunk in the sinking.
The necessary defrosting can be provided in various ways, including the circulation of warm air in the barrel, the supply of warm coolant to the freezing columns, etc. A program for calculating the defrosting parameters has been developed, depending on the combination of methods for supplying warm air and heated brine.
It is determined that in order to create reliable conditions for the production of plugging of the fixing space and water-proofing of the tubing support, the most favorable option is thawing by feeding warm air into the barrel and circulating the coolant at a temperature of +15°C.

Number of views: 256

SORBENT-BASED METHOD OF SOILS DETOXIFICATION FROM HEAVY METALS

Vera V. Yurak, Raphael A. Apakashev, Niyaz G. Valiev, Maxim S. Lebzin

Abstract. The sorbent-based method is one of the key methods for solving the problem of limiting the mobility of pollutants and the effective implementation of reclamation works. Despite the level of knowledge of the problem, the use of the sorbent-based method is of a fragmented experimental nature. Objective: to study the experience of implementing the sorbent-based method for the adsorption of heavy metals in order to determine the most promising compositions of sorbents for further research work on their improvement. 
Methods: General scientific methods were used, such as dialectical, historical, analysis, synthesis, comparison, grouping, as well as systematic and empirical approaches. 
Results: The presence of pluralism of definitions in relation to the term “heavy metals”was revealed. The main criterion for attribution is the relative atomic mass of more than 50 g/mol. An additional criterion is the density, which is approximately equal to or greater than the density of iron (rounded 8 g / cm3). There are other classifications that rely on threshold density or atomic mass values. It is proved that the main role of the immobilization of heavy metals is their transfer to new, more geochemical stable phases by sorption, precipitation, and complex formation processes. The widespread use of the sorbent-based method, which solves the problem of converting heavy metals into a sedentary form and difficult-to-dissolve compounds, has been identified. It is revealed that an important process affecting the mobility of heavy metals in the soil is their fixation with humus. It is established that rocks and minerals have pronounced sorption properties. The most common rocks are clays. They are characterized by a significant sorption capacity and a high specific surface area. In order to increase the sorption properties, the materials can be subjected to various modifications. Peat occupies a special place among effective natural sorbents. The development of technologies for the creation and use of new sorbents made from industrial waste is a promising direction. A method of remediation based on the use of ameliorants–stabilizers of heavy metals has been developed: among the mineral elements of the solid phase, fine clay and ferrous minerals are isolated; compost and manure are often used as organic stabilizers. The possibility of rerational use of industrial waste components as meliorants-stabilizers of heavy metals is investigated, and the sediments of water treatment at filtration stations are of interest in this regard. The remediation potential of water treatment sediments can be enhanced by joint application with natural or modified peat.

Number of views: 256

MONITORING AND MANAGEMENT OF THE RIVER’S ECOLOGICAL STATE METHODOLOGY USING INTEGRAL BIOMARKERS AND QUALITY MANAGEMENT METHODS

Gorbunova T. L., Matova N. I.

The water quality of most rivers near the settlements is below the optimal level, taking in account natural ecosystems condition and numerous needs of various users. Considering the environmental, economic and social importance of this factor, measures are required to improve natural reservoirs water quality management conducted by local civil autonomy and various levels of government. The goal of this work is to offer methodical recommendations on the system design of collecting, analyzing and forming the river’s water and ecosystems conditions database for the information support of complex management decision-making directed to accomplishment and preservation of the water bodies specified functional characteristics. Presently none of the existing methods of water environment assessment can take into account all possible biological communities’ responses to the various stress factors and their combinations impacts. For every type of impact the corresponding to it approaches in sampling and analysis methods are used; values of such methods are often difficult to collate and, especially, provide statistical evaluation of the water streams processes. The presented methods are based on the multimetric index application, which include  parameters, reflecting biological communities biodiversity and stability in mountain type rivers, tolerance degree of the constituted them water organisms to external impacts and water environment toxicity for its inhabitants.    Modern quality management, including quality of the processes, has a wide range of proven tools. The offered quality management process improvement method of the natural watersheds experiencing an anthropogenic pressure, is aiming to reach stability and guaranteed quality of the natural waters, based on the DMAIC quality management methodology and statistic quantitative methods united under the Six-Sigma approach. This article is the first in publications series devoted to the description of the methodology of the rivers ecological state monitoring and management using integrated biomarkers and quality management methods. Formed during the study organizational and methodical approaches can be applied to digital transformation of effective administrative decisions making process in sphere of water objects protection and development of the river’s catchment territory ecological planning within the project of the RF Construction Ministry “The Smart City”.

Number of views: 380

ASSESSMENT OF THE POSSIBILITY OF USING PEAT-DIATOMITE IMPROVER IN THE DEVELOPMENT OF MEASURES FOR THE ENVIRONMENTAL REHABILITATION OF DISTURBED ECOSYSTEMS

N. Yu. Antoninova, A. I. Usmanov, L. A. Shubina, A.V. Sobenin

One of the main factors determining the transformation of natural technogenic complexes is the storage of large masses of industrial waste on the day surface, and their further transformation leads to a change in geochemical processes in landscapes associated with dumps. Objective. On the basis of the experimental studies performed, to evaluate the effectiveness of the use of peat-diatomite ameliorant in the development of measures for the ecological rehabilitation of disturbed ecosystems. Research methods. The content of copper ions was determined by the atomic absorption method using a Spectr AA-240 FS (Varian Optical Spectr. Instrum, Australia). Mineralization of samples to determine the gross copper content was carried out in concentrated HNO3 using a MARS 5 laboratory microwave system (CEM, USA). The mobile forms of copper were determined in extracts of 0.5 M HNO3 in a ratio of 1:25 (soil: solution). Mine waters of the former Degtyarsky mine with a copper content of 4.61 mg / L were used as a model solution. Technogenic soil for microfield experiments was selected during the summer field research. Peat-diatomite ameliorant own development of “Ekoinnovator”. Research results. According to the results of the analysis of the obtained experimental data, the tendency of the sorption process from 4.61 mg/l to 1.754 mg/l is clearly visible when using "diatomite" as a sorbent, and the introduction of a peatdiatomite meliorant in the composition of which sapropel is also Therefore, using reclamation techniques by introducing mineral and organic fertilizers, it is possible to regulate the mobility of copper ions, and the revealed nature of changes in the amount of mobile copper compounds should be taken into account in the development of environmental protection measures for the ecological rehabilitation of disturbed natural ecosystems.

Number of views: 434

UAV PHOTOGRAMMETRY-BASED FOR OPEN PIT COAL MINE LARGE SCALE MAPPING, CASE STUDIES IN CAM PHA CITY, VIETNAM

Nguyen Quoc Long, Le Thi Thu Ha, Si Son Tong, Kim Thi Thu Huong

The use of lightweight Unmanned Aerial Vehicle with the aerial photogrammetry approach to construct the Digital Surface Model (DSM) has been effectively applied for various types of topography. However, the ability to carry out this approach for huge active open coal mines is insufficiently investigated, furthermore, the influences of topographical factors on the accuracy of DSM are ambiguous. This experiment attempts to apply the UAV method for the two active coal mines with the total area of 7.99 km2, exploited at a range from -300 m to 300 m altitude to figure out the effect of topographic factors on the accuracy of DEM constructed from UAV images. A total of 972 UAV images and 17 ground control points have been coupled to construct DSM of the mines. Besides, 16 checking points located at different elevations are used to evaluate the accuracy of DEM and to define the influence. DEMs are generated with the maximum RMSE of 0.086 m, 0.099 m, and 0.170 m corresponding to X, Y, and Z dimensional errors. The results show the unclear correlation between the vertical accuracy of DEM and the relative elevation (R2=0.064), the general slope of the mines, and the number of ground control points using in the coal mines as well.

Number of views: 489

UNDERGROUND MINING EQUIPMENT KITS COAL IN SHALLOW BEDS

V. I. Efimov, N.I. Abramkin, V.V. Vernigor, B. Kh. Khakimov

In Russian practice, at the author of the mines of the revolution, equipment was used, which was well made at the pest of domestic factories. In view of the core bankruptcy of the domestic factories, the coat of arms of the miners were forced to carry the burden and had the choice to buy foreign equipment.. In 90-ies tax on trail equipment, which was not produced in Russian boards, was not collected at all. The miners bought the equipment abroad, without any additional problems for the equipment import did not arise. Powered roof support and shearers are not produced in Russia and the plants had to buy them abroad both the avalanche and the separate equipment. The term fund "complex" pest has a conditional blue character, the conclusion reflecting taking only the stage of the kinematic announcement of the connection, the input of the electrohydraulic and if the electronic system suddenly controls interchangeable author sets of equipment address. temperament It is advisable to revise the concept of more classification of the kiln cleaning mechanized complexes and the lighthouse to adjust the core of the customs due to legislation to address some of the tinder customs duties on the author of the mining equipment.

Number of views: 408

MANAGEMENT COMPETENCY AND ENTREPRENEURIAL INTENTION OF THE 60-YOUNG VILLAGERS IN A PART OF SLOPE OF MT. ARJUNA EAST JAVA INDONESIA

Lasman Parulian Purba, Yustinus Budi Hermanto

Our interest is to explore such a characteristics of the young villagers who live in the slope of Mountain Arjuna, East Java Province of Indonesia prior to their existing management competency and existing entrepreneurial intention.

Number of views: 445

VARIABILITY OF WINTER EXTREME LOW TEMPERATURES OF THE SURFACE AIR LAYER IN THE LAKE SEVAN BASIN (ARMENIA)

V. G. Margaryan

The purpose of this work to study, analyze and evaluate the patterns of spatial variability of long-term fluctuations in winter extreme low temperatures of the surface layer of atmospheric air in mountainous territories of Armenia (for example, the lake Sevan basin). To achieve this goal, the results of actual observations by Armhydromet and the available literary sources have been collected, processed and analyzed. As a result of the analysis of the values of extreme low temperatures, it can be noted that the genesis of winter extreme low temperatures is different in the territories under consideration. Winter extreme low temperatures stand out for their uneven distribution – they range from -26.3 to -38.1. For the calculation of winter extreme low air temperatures of unexplored or poorly studied territories, correlations were obtained between the value of extreme low temperatures and the altitude of the area above sea level. In the study area, a tendency towards an increase in winter extreme low temperatures is mainly observed. The scientific novelty of the obtained results lies in the fact that in modern observational materials, for the first time, the regularities of the variability of the spatio-temporal distribution of winter extreme low temperatures of the surface air layer in the lake Sevan basin are estimated. Findings • The study of the patterns of variability of the spatial-temporal  distribution of winter extreme low temperatures of the surface air layer under conditions of  regional and global climate change is an urgent task of modern geographical science; • Winter extreme low air temperatures are mainly due to the nature of the underlying surface and the features of the relief. The smallest values are observed not in high-altitude zones, but in those places where cold air accumulates (that is, in depressions). In winter, in the hollow valleys, an inversion is mainly observed- in parallel with the height, the air temperature rises. In valleys, as a result of the accumulation of cold air, low temperature conditions can be observed for quite a long time; • The study area is distinguished by a characteristic regime and an uneven spatial distribution of winter extreme low temperatures. They range from -26.3 (Semenovka) to -38.1(Masrik). • Winter extreme low temperatures rise up to 2000-2100m with altitude, and on the contrary, they decrease at altitudes above 2000-2100m. The vertical temperature gradient is -0.5C/100m and 0.8C/100m, respectively; • On the basis of the obtained correlation between winter extreme low temperatures and terrain heights, two regions were identified: 1) heights up to 2000-2100m and 2) 20002100m and higher; • Temporal trends during perennial winter extreme low temperatures are mixed. In the study area, these is a predominance of positive trends. Negative trends are characteristic for the period 1935-1966 at the Sevan, Masrik and Martuni meteorological stations; • In the study area, winter conditions become thermally milder, which should be taken into account when developing strategic programs for the future development of this area.

Number of views: 367
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ISSN 1998-4502 (Print)                                                            ISSN 2499-975Х (Online)