Home – Home – Jornals – Journal of Applied Mechanics and Technical Physics 2022 number 4

We present results of new mineralogical, geochemical, geochronological, and isotope (Sm-Nd, Rb-Sr, and O) studies of the volcanic rocks of the Tyya complex in the Olokit trough. These are normal tholeiitic basalts and scarcer basaltic andesites forming a fractionated series with mg# = 45-65, medium TiO2 contents (0.73-1.62 wt. %), low P2O5 contents (0.04-0.25 wt. %), and a significant domination of Na over K (Na2O/K2O = 2.1-50.0). The rocks are metamorphosed to greenschists, which are composed of chlorite, actinolite, epidote, and albite with quartz, titanite, ilmenite, and magnetite impurity. The metabasalts have is an age of 915 ± 5 Ma (zircon U-Pb dating) and are characterized by wide variations in εNd(T) (-3.5 to -11.9) and 87Sr/86Sr (0.70602-0.70732) and high δ18O values (9.0-15.2 ‰) as compared to the mantle ones. According to the isotope-geochemical characteristics, the studied metabasalts have features of both IAB and E-MORB. The Tyya metabasalts might have resulted from the melting of the lithospheric mantle with a subductional component. Comparison of the studied rocks with volcanic rocks of recent geodynamic settings shows their similarity to basalts of back-arc basins. The Tyya metabasalts might belong to a back-arc basin of the late Mesoproterozoic Nyurundukan island arc system.

In the Central Asian Orogenic Belt, Li-F granites formed in magmatic areas of different ages within a wide time interval, 321-134 Ma. The Li-F granites compose large multiphase plutons (Janchivlan and Baga-Gazriin Chuluu) and small intrusions, have specific mineralogic and geochemical characteristics, and show enrichment in Sn, W, Li, Rb, Ta, and Nb, thus forming concentrated mineralization at the late magmatic and postmagmatic stages. The late Paleozoic and Mesozoic small intrusions (Kharagul, Urugudei, Bezymyanskii, Henteyn, and Turga) are high-alkali Li-F granites enriched in Zr, Nb, Hf, Th, U, and REE, which differ from ore-bearing Li-F granites in mineral assemblages and geochemical features. Such granites can be classified as an individual subtype of rare-metal granites. Irrespective of geochemical characteristics, the Li-F granites of the studied provinces in Central Asia are geochemically different from typical collision-related granites resulting from the melting of the upper continental crust. It is shown that the formation of rare-metal magmas with different geochemical characteristics is related to the mantle-crust interaction. The geochemical evolution of Li-F granites is significantly contributed to by the activity of mantle fluids containing trace elements and by the differentiation of granitic magma in the crustal intermediate chambers, which is favorable for the formation of associated rare-metal mineralization.

The Kopto deposit (northeastern Tuva) is assigned to gold ore objects with a combination of the Au-Cu-skarn and superposed quartz-gold-sulfide stockwork types of mineralization. From the surface, the ores underwent intense oxidation, which formed a zone of secondary gold enrichment, containing a supergene paragenesis with gold and silver chalcogenides and newly formed gold. The depth of distribution of oxidized ores from the surface is 80-90 m. The Au content varies from fractions of ppm to 150 ppm (on average, 30.8 ppm). Using computer thermodynamic modeling, it is shown how the ore gold-sulfide-quartz association transformed under oxidizing conditions with a decrease in the pH of solutions. Gold becomes more and more high-grade; acanthite appears and disappears; limonite prevails (pH = 1.65; Eh = 0.69 V). The conditions for the stability of pyrite, iron hydroxides, and gold and silver chalcogenides (petrovskaite (AgAuS) and uytenbogaardtite (Ag₃AuS₂)) have been estimated. It requires weakly acidic solutions with pH = 5-6 and Eh values close to zero, which ensures the stability of thiosulfate and hydrosulfide complexes of noble metals. The main difference between solutions in equilibrium with petrovskaite and uytenbogaardtite is the Ag/Au ratios, which are maximum in the first case and approximately equal in the second. The paper is concerned with a comparative analysis of the morphologic features of gold from primary and oxidized ores of the Kopto gold deposit. The aim of this work is to identify a set of signs of the supergene nature of gold and to assess the extent of its redistribution.

Electrical measurements in water areas, as well as on land, are carried out to study the electromagnetic (EM) properties of geologic objects. The specifics of aquatic electrical prospecting are associated with the specific influence of a water column. We present numerical calculations of the EM signal of the transient process for electrical lines in the axial region of the source in 50-250 m deep sea waters in order to demonstrate the manifestation of induced polarization (IP) in the transient-process signal at different setups, to reveal the differences in the manifestation of galvanic (GP) and double induced (DIP) polarization in the transient-process signal, and to explain the causes of these differences. To study the influence of the size of the setup on the manifestation of IP during the transient process, we analyzed the changes in the signal of the transient process (Δ U ( t )), in the finite difference between the signals of the transient process (Δ² U ( t )), and in the transform P1( t ) (the ratio of these values) for a horizontal electrical setup with a 50 to 2000 m long source ( AB ) and a 50 to 2000 m long three-electrode measuring line ( M ₁ M ₂ M ₃) and with the distance between the centers of the source and the measuring line M ₁ M ₃ (spacing, r ) from 100 to 4000 m. Some of these parameters are used in differential-normalized electrical prospecting (DNEP). Comparison is made for Δ U ( t ), Δ² U ( t ), and their transforms in the conducting and conducting polarizable models under the same conditions. The setup was placed on the surface and inside a conducting medium (a sea shelf water column) with a conducting polarizable base (geologic medium (earth) covered with a water layer). The polarizability of the base was taken into account by introducing a frequency-dependent resistivity, using the Cole-Cole formula. The performed calculations show that the components of the transient process that are associated with the formation of the EM field and with GP and DIP manifest themselves in different ways at setups of different sizes at different depths. In water area, IP manifests itself in two ways, being associated with both galvanic and eddy currents. In previous practical measurements, DIP was considered to be associated with interference, but this signal is simulated and can be regarded as the information about IP. The factor influencing the IP manifestation in the transient-process signal is the reduced setup height ( h _Δ), i.e., the distance between the setup and the sea bottom (the polarizable base of the model) referred to the AB length. Depending on the reduced setup height, the IP signal in the transform P 1( t ) can manifest itself as an ascending branch at later times or can appear as a descending branch passing into the negative values of P 1. The duration of the pulse impact and the measurements of the transient process affect the contrasting manifestation of the polarizable base in the signal, but the measurements under setup towing impose certain restrictions. The optimal parameters of EM survey for studying IP should ensure a sufficient polarization range and the proper quality of measurements. The software used in the calculations was developed by OOO Sibirskaya Geofizicheskaya Nauchno-Proizvodstvennaya Kompaniya.

We present results of experimental measurements of the complex dielectric permittivity (CDP) of sand and powdered quartz granules with mass-averaged particle sizes of 5 to 250 μm, saturated with distilled water and NaCl solutions with a conductivity of up to 0.77 S/m. The CDP spectra were measured in the frequency range from 1 kHz to 8.5 GHz. The spectra at frequencies above 1 GHz were simulated using a refractive three-component mixture model. In the frequency range from 10 kHz to 1 GHz, the CDP spectra were simulated by three relaxation processes, using the Debye and Cole-Cole formulas. It is shown that the conductivity of the sample at a frequency of ~5 kHz is not proportional to the conductivity of the saturating solution. The intensities of two low-frequency processes are more intimately correlated with the conductivity of the sample than with the volume fraction of the solution. The relaxation times of the low-frequency and high-frequency processes are statistically correlated with the average particle size, and the relaxation time of the low-frequency process is additionally correlated with the specific surface area of the particles. We estimated the conductivity of the saturating solution at which the correlation is the strongest.

Calibration experiments of magnetic resonance sounding (MRS) were carried out on the ice of the Ob’ reservoir. For the first time, a comparative quantitative analysis of the contribution of electromagnetic shielding and the Bloch-Siegert effect to the magnetic-resonance sounding signal was carried out, and the asymmetry of this contribution when detuning from the resonant frequency was investigated. The results of theoretical calculations without regard to the Bloch-Siegert effect differ about three times from the experimental data at the maximum intensity of the radio frequency pulse for the experimental data. At the same time, when taking into account the interference of electromagnetic shielding and the Bloch-Siegert effect, the results of calculating the amplitude and phase of the signal best approximate the field experimental data. Based on the good agreement between the experiment and the theoretical calculations taking into account the interference of electromagnetic shielding and the Bloch-Siegert effect, it is demonstrated that this model should be used to solve the direct and inverse problems of magnetic-resonance sounding of underground aquifers. The results obtained allow us to calibrate the MRS method and use it not only as an indicator of underground water but also as a means of quantitative measurement. The necessity of taking into account the Bloch-Siegert effect in real field conditions is demonstrated by the example of MRS studies in the Ebro River valley (Spain). When taking into account only electromagnetic shielding (without regard to the Bloch-Siegert effect), the signal amplitude differs nearly twice at the maximum pulse intensity for experimental data, and the signal phase differs 12 times at the maximum pulse intensity. Therefore, in previously published works, approximation of the experimental data using the model without regard to the Bloch-Siegert effect was made by adding layers at depths close to the maximum for this type of antenna (approximately 50 m). In reality, however, these layers do not exist; they appear only as an artifact of the model without regard to the Bloch-Siegert effect. The best approximation of the experimental data can be achieved by taking into account the interference of electromagnetic shielding and the Bloch-Siegert effect.

This paper presents a schematic summary of comprehensive analysis of seismic, reflection profiling, and hydroacoustic data on faults which caused sediment deformation in the central segment of the Central Baikal basin. According to the tectonophysical analysis results, the fault pattern within sediment fill has been recognized as zone-block, i.e., it represents a network of high-density fracture zones limiting weakly deformed blocks. The structure of large NE-trending fault zones (Olkhon, Beregovoy, Gydratny, and Svyatoy Nos) is controlled by main fault planes (or their segments) bounded by subsidiary faults. Geomorphic expression of NW cross faults in the sedimentary cover as broad zones of smaller-scale fractures accounts for early stages of the evolution of basement faults. In a longitudinal direction, they divide the basin into large fragments. The zone-block structure of the sedimentary strata was developed in different stress regimes: strike-slip and extension at the early and late orogenic rifting stages, respectively. At the modern stage of tectogenesis, the established network of fault zones controls the gaseous (including hydrate formation) and seismic activity expression in the subsurface. Hydrate-bearing mud volcanoes and seeps are confined to major faults, while earthquake epicenters are confined to fault zones and form clusters at junctions of large NE-trending faults with NW-oriented extension zones and E-W left-lateral strike-slip faults.

Dynamic models of the seismic, geological, and flow characteristics of a reservoir are the main tool used to evaluate the potential of drilling new infill wells. Static geological models are mainly based on borehole data combined with dynamic analyses of production dynamics. They are used to determine the redevelopment of and adjustments to new drilling locations; however, such models rarely incorporate seismic data. Consequently, it is difficult to control the changes in geological models between wells, which results in the configuration of well positions and predicted results being less than ideal. To improve the development of adjusted areas in terms of their remaining oil contents, we developed a new integrated analysis that combines static sediment modelling, including microfacies analysis (among other reservoir and seismic properties), with the production behaviour. Here, we illustrate this new process by (1) establishing favourable areas for static geological analysis; (2) studying well recompletion potential and the condition of nonproducing wells; (3) conducting interwell analyses with seismic and sedimentary data; (4) identifying potential sites constrained by seismic and geological studies, as well as initial oilfield production; (5) providing suggestions in a new well development plan.

An experimental-theoretical study has been performed to investigate the disturbances generated in the boundary layer on a plate by individual microdischarges in a dielectric barrier discharge plasma actuator. It has been shown that disturbances in the near field behind the actuator can be interpreted as nonstationary banded structures which away from the actuator are transformed into a fan of growing Tollmien-Schlichting waves. It has been found that the length of the transition zone in which disturbances of the first type predominate is anomalously great and reaches a value of the order of 100 boundary layer displacement thicknesses. This should be taken into account when analyzing parasitic stochastic disturbances produced by plasma actuators used to control laminar-turbulent transition.

A resonant pulse transformer with impact excitation is compared with a system of coupled pendulums of different masses tuned to resonance. Conditions for complete energy transfer during one-half beat cycle are obtained for a Tesla transformer and coupled pendulums. The requirements for the system parameters and initial conditions necessary for complete energy transfer in the case of two spring-coupled pendulums with different masses and the same length were theoretically determined and experimentally tested for the first time. The dependence of the shortest time of energy transfer from one oscillator to another on the system parameter is obtained.

Crystallization processes in the case of modification of the surface layer of an iron-based alloy (Fe-C) subjected to a pulse action of a high-frequency electromagnetic field for substrate heating and melting are numerically simulated. The processes of heating, melting, and subsequent solidification of the metal are studied with the use of a mathematical model that describes thermodynamic phenomena. It is postulated that nano-sized particles with a high melting point uniformly distributed over the melt volume favor rapid crystallization during melt supercooling owing to heterogeneous nucleation. It is found that the nucleation and crystallization conditions in different areas of the melt volume are essentially different, and the maximum number of crystallization centers arise in regions where heat removal proceeds with the greatest rate. The particle size distribution in the crystalline structure in the solidified metal volume is estimated.

The behavior of the velocity component of silicon melt particles tangent to the free boundary during crucibleless zone melting in a magnetic field is studied. It is shown that the neglect of convective terms in the skin layer adjacent to the free boundary leads to erroneous results: the tangential velocity cannot reach a constant value when moving along the normal to the free boundary, which in turn leads, as shown earlier, at full solution of the problem, to an order of magnitude decrease in the characteristic velocity of melt particles outside the skin layer.

To take into account certification modes in optimization problems of the nacelle of a bypass turbojet engine, we developed a method for numerical determination of the characteristics of the air intake in the engine operating regime with a crosswind. The flow and aerodynamic characteristics of the air intake in these regimes were studied. Experiments were carried out in a wind tunnel to validate the calculation method based on the solution of the Reynolds-averaged Navier-Stokes equations. The laminar-turbulent transition was simulated using the the Menter turbulence  -model taking into account the compressibility of the gas.

One of the main methods of searching for gas hydrate deposits is seismic exploration and acoustic logging. For correct processing and interpretation of measurement data, it is necessary to know the acoustic properties of hydrate-containing rocks, which can be studied on the basis of laboratory experiments and adequate mathematical models. In this paper wave propagation in a hydrate-containing porous medium is investigated. The skeleton is considered to consist of grains cemented with gas hydrate, and is modeled by a homogeneous solid phase with effective parameters. The elastic moduli of the composite skeleton of a porous medium are calculated from the elastic moduli of the grain material and hydrate using a well-known method. The velocities and attenuation coefficients of linear waves are calculated within the framework of a two-velocity model of a porous medium. The calculated data are compared with the experimental data of other authors on sound velocities in hydrate-containing porous samples. The influence of the properties of the base rock, the saturating fluid, and hydrate saturation on the propagation of linear waves is studied.

Bypass surgery is widely used in the treatment of cardiovascular diseases. The problem of optimal location of cerebral vascular anastomosis is considered. An electrical circuit model of circulation of large cerebral vessels is constructed whose optimal parameters are determined numerically using swarm intelligence methods. The objective optimization function was taken to be the pressure after shunting compared with the pressure before surgery. This method was first used to solve the problem of formation of cerebral vascular anastomoses. It is shown that the obtained the results are in good agreement with the data of real surgeries.

We study the dynamics of a thin attached cavity formed as a result of an instantaneous stop (impact) of a circular cylinder in a disturbed fluid. The fluid flow immediately following the impact and the initial separation zone are determined using the classical model of impact with separation. To study the cavity collapse process, a direct asymptotic method is used, in which the expansions of the main hydrodynamic characteristics are carried out in terms of a small parameter equal to the dimensionless acceleration of the cylinder before impact. In the leading asymptotic approximation, a problem with one-sided constraints is formulated, from the solution of which the motion of separation points is determined and the process of collapse of a thin cavity is described. Taking into account the special equations of the boundary layer, the analysis of the internal free boundary of the fluid is carried out.

The spreading behavior of liquid droplets bridged by filaments is theoretically studied in this work. In our model, the wetted droplets between the fibers can be in one of three different equilibrium morphologies: barrel, bridge, or liquid column. The results show that small-volume droplets undertake a reversible column-to-bridge transformation. However, two distinct transitions are observed for large-volume droplets: column-to-bridge transition in the case of separated fibers and bridge-to-barrel-to-column transition for closely spaced fibers. Particular attention is paid to a hysteretic behavior of large-volume droplets at various inter-fiber distances. It is found that the our results are in good agreement with available experimental data

Thermofluid features of the flow through ribbed ducts for various rib arrangements and configurations are investigated numerically. Simulations are performed in a wide range of Reynolds numbers. The impacts of roughness factors (rib width, rib pitch, and rib height), rib arrangements, and rib configurations on the thermal performance of ribbed channels are examine.

In freshwater ecosystems, the efficiency of transfer of essential substances from phytoplankton to zooplankton, measured as the ratio of the production of these substances in zooplankton to their production in phytoplankton, determines the functioning of higher trophic levels. In addition to carbon, primary producers transfer essential substances up the trophic chain, including polyunsaturated fatty acids (PUFA), nitrogen (N), and phosphorus (P). The transfer efficiency of these substances varies greatly in nature depending on environmental factors, thus affecting the quality of biological resources. The goal of this review was to analyze mechanisms regulating the efficiency of transfer of essential substances from phytoplankton to zooplankton and to establish the main factors that may have impact on the efficiency of their transfer.

Since the second half of the 70s of the twentieth century, the ecosystems of lakes Batorino, Myastro and Naroch have undergone stages of anthropogenic eutrophication, targeted deeutrophication and benthification caused by the introduction of the filter-feeding mollusk Dreissena polymorpha Pallas. The set of continuous series of seasonal mean values of eight parameters of each ecosystem obtained in 1978-2015 were analyzed by mathematical-statistical methods of principal components (PCA) and singular spectra (SSA). The analysis showed that the complex long-term dynamics of the set of selected characteristics of the ecosystems of Lake Batorino and Lake Myastro during this period of time was described by three main components by 92 % and 90 % respectively, and the ecosystem of Lake Naroch - by five main components by 94 %. A biological interpretation of these principal components was proposed, i. e. a hypothesis was put forward as to which factors had the greatest influence on the ecosystem dynamics in those years. The first main factor which determined the dynamics of the ecosystems of lakes Batorino, Myastro and Naroch by 63, 65 and 43 % respectively, was interpreted as the resistance of the lake ecosystem to variable biogenic load, which is inversely related to the trophicity of the reservoir. The second main factor, whose contribution to the dynamics of the Naroch lakes ecosystem parameters (in the same order) amounted to 21, 15 and 22 %, was interpreted as solar radiation activity. The interpretation of the third main factor depends on the properties of a particular ecosystem. For ecosystems which are not deficient in biogenic elements (Lakes Batorino and Myastro, the contribution of the factor to the ecosystem dynamics was 8 and 10 %), it can be interpreted as the transfer of the created primary organic matter to consumers of the next trophic level, associated with the structure of the food chain in the ecosystem. For an ecosystem in which the process of primary production formation is limited by the available amount of biogenic elements (Lake Naroch, 13 % contribution of the third main factor to ecosystem dynamics), it is this available amount of nutrients that is the third main factor affecting its long-term dynamics. The fourth main factor, which determined the dynamics of Lake Naroch ecosystem by 9 %, is also connected with the process of primary production formation. Only the fifth main factor, which determined the dynamics of the ecosystem of Lake Naroch during the time period under consideration by 7 %, controls the transfer of primary production to consumers of the first trophic level. Thus, the conducted statistical study not only confirmed empirically established regularities in the functioning of lake ecosystems, but also for the first time allowed us to obtain quantitative assessments of significance of each main factor for ecosystem development in specific circumstances, depending on the degree of trophicity of water body.

In the bottom sediments of lakes Cheko and Zapovednoye, located in the southern part of the Evenk region (Krasnoyarsk Territory), the distributions of charcoal particles >100 microns have been analyzed. The background content of charcoal particles in sediments up to 1500 years ago was not less than in recent sediments. Thus, evidence was obtained that the intensity of fires in the vicinity of the studied lakes in the past was not less than at present, and during the XVI-XVIII centuries it was possibly even higher. Therefore, a sharp increase in forest fires in recent times reported for other regions is not confirmed for this territory, which is probably due to the lack of economic activity due to the extremely low population density. In Lake Cheko, a local maximum of charcoal particles was revealed at the sediments corresponding to the year of 1908, presumably being the trace of an extensive forest fire resulted from Tunguska 1908 catastrophe.

The results of the analysis of changes in the productivity of forest, bog and arable ecosystems in the eastern part of the Belarusian Polesye in 2000-2020 are presented. Satellite imagery (MODIS radiometer of the Terra satellite) was used. Ecosystem productivity was assessed according to the normalized difference vegetation index (NDVI). The correlation between changes in climatic indicators and NDVI has been studied. It was found that the studied ecosystems differ in response to climatic changes. Statistically significant positive NDVI trends were found for forest and bog ecosystems. A reliable correlation of this indicator with the average summer temperature and summer precipitation has not been established. Arable ecosystems are characterized by the absence of a statistically significant trend in productivity and a significant negative correlation of NDVI with temperature and a positive correlation with precipitation. The effect of climatic characteristics on the NDVI of arable ecosystems depends on their soil type.

The paper presents modern data on the demographic structure and population size of C. calceolus on the territory of European Russia. The assessment of the species distribution and population size is based on the classification of the terrestrial ecoregions of the World. The long-term dynamics of the number and age structure (150 populations) of C. calceolus was revealed for the 20-year research period 1997-2020. It has been reliably determined that the number of generative plants is positively related to temperature indicators, while the number of pregenerative groups depends on humidity factors and negatively on temperature. Three types of basic age spectra were identified: 1) centered 3 : 10 : 47 : 40 (juvenile (j): immature (im): virginal (v): generative (g)), the most common in the European part of the Russian Federation (RF); 2) bimodal 15 : 26 : 33 : 26 (j: im: v: g), mainly found in the western regions; 3) right-sided 0 : 3 : 13 : 82 : 2 (j : im : v : g : s), which is steadily appears in the continental climate of the eastern regions of European Russia. The current baseline spectra of C. calceolus populations differ from the baseline spectrum of the species given in the 20th century. The base spectra reliable depends on ecological-phytocenotic plant community structure and abiotic features of habitats, it was shown using the scales of ecological indicator values.

Two physico-climatic factors that were both distant and recent prerequisites and a trigger for the transformation of a clone of the ancestral pseudotuberculous microbe Yersinia pseudotuberculosis O:1b, the causative agent of Far East scarlet-like fever (FESLF), into a population of a derivative of the plague microbe Y. pestis are considered. A distant prerequisite was the aridization of the Central Asian landscapes in the second half of the Cenozoic and the formation of the Gobi arid zone. Arid conditions in Central Asia led to the formation of adaptive species-specific protective behavior in the Mongolian marmot-tarbagan ( Marmota sibirica ) during the installation of a wintering burrow plug, which subsequently contributed to the mass infection of FESLF animals during hibernation in an aberrant (traumatic, non-alimentary) way. The recent prerequisite and real trigger for the speciation of Y. pestis was the onset of the last maximal (Sartan) cooling in Central Asia at the turn of the Pleistocene and Holocene, 22-15 thousand years ago. Freezing of the Mongolian marmot’s wintering burrows caused a behavioral shift in the larval population of the marmot flea Oropsylla silantiewi - a transition in the cold winter-spring months of the year from saprophagy in the nest lining of burrows to hematophagy on the bodies of sleeping animals. Larval scarifications in the oral cavity of sleeping marmots became the entrance gate for a unique traumatic FESLF infection. The constellation of climate change, the heterothermic (and, accordingly, heteroimmune) state of family groups of sleeping marmots, year-round reproduction in the wintering burrows of the flea O. silantiewi , together with behavioral shifts in marmots and fleas caused by climatic changes, led to the formation in the parasitic system of “ Marmota sibirica - O. silantiewi” of conditions in which the transformation of the FESLF microbe into a peripatric plague pathogen took place. Thus, the different climatic changes in the Cenozoic led to a change in the behavior of the Mongolian marmot and later the fleas parasitizing it, and the change in the behavior of marmots and fleas caused the transformation of a clone of a pseudotuberculous microbe into a population of the plague microbe.

Ecological condition of extrazonal larch sparse trees in the val.y of Mongayurbey river (the Taz peninsula) has been studied on the base of remote sense data and tree-ring chronologies. The site is one of the northernmost enclaves of taiga vegetation in Western Siberia. The analysis of Terra-MODIS satellite images from 2000 to 2020 showed that vegetation index value (NDVI_mean) revealing average quantity of photosynthetical active phytomass over the summer period depends most on the average annual air temperature (correlation coefficient R=0.69). However, there is no statistical. significant trend of the vegetation index despite the stable trend in the rising of summer temperatures that is connected to the inertness of the shrub-moss-lichen ground cover. Correlation of maximum vegetation index values (NDVI_max) and total width rings (TRW) of Larix sibirica Ledeb. revealed close link ( R = 0,72) on the border with the watershed, where is the young tree stand with the most crown density and abundant undergrowth. On the contrary, there is a digression of the tree stand in the val.ys areas, associated with deterioration of nature conditions (changes in drainage, soil characteristics, permafrost and geochemical conditions). At continuation warming, we can expect the spread of larch trees from the river floodplain towards watershed that confirms the current movement to the north of the border of forest vegetation.

Micromycete F. poae (Peck.) Wollenw. is a dominant member of pathogenic mycocenosis of host plant organs in Western Siberia. The main ecological niche of the first order, where the T and R tactics of the phytopathogen are implemented, are the underground organs of host plants, and the additional ones are generative organs. Implementation of tactics B is carried out in econiches of the second order - soil (main) and seeds (additional). The degree of implementation of the F. poae ecological niche in underground plant organs depends on a number of factors, among which the main role is played by the resistance of the host plant, hydrothermal conditions of vegetation, suppressive soil activity, and interspecific relationships with other phytopathogens. Under certain conditions, F. poae loses its dominance and, by the end of the growing season, can be completely displaced from the underground organs of plants by its competitors Bipolaris sorokiniana Sacc. Shoem. and F. oxysporum Schltdl. The overlap of ecological niches in terms of the frequency of joint occurrence in F.poae was maximum (up to 100 %) with F. oxysporum , which indicates a sharp competitive relationship. Minimal overlap (5-10 %) was found with F. sporotrichioides Sherb. and with F. sambucinum Fuckel. The strength of the influence of the year on the suppressiveness of the rhizosphere soil to F. poae in the phases of plant development varies from 29.2 % to 90.9 % and is statistical significant at the 1 % significance level. The coefficients of correlation between the induction of varieties of soil suppression to F. poae and its representation in pathogenic complexes by vegetation phases were R = -0.546 ± 0.216 … -0.765 ± 0.152 ( p < 0.05). relationship with F. oxysporum , F. solani Koord. and B. sorokiniana , and neutral ones with signs of competition with F. equiseti (Corda) Sacc. and F. sambucinum . The implementation of an additional ecological niche of the first order F. poae in the generative organs of plants was determined by the conditions of the year and the structure of the generative organs.

In this study, the gauge and phase transition theories are used to develop an elastoplastic model of geomaterials with dissipation. Displacements and plastic distortions are selected as the independent variables. The initial Lagrangian is constructed by the requirement of invariance of the Lagrangian with respect to translational transformation. To take into account the continuous structural phase transition effect of plastic deformation of geomaterials, fourth- and sixth-power terms of the distortion tensor are added to the initial Lagrangian. The differential motion equations of media with dissipation and the corresponding boundary conditions are obtained based on Hamilton’s principle. Generalized Hooke’s laws are obtained on the basis of the kinematic variational principle. One special case, dilatation-compaction deformation case, is discussed, and the obtained equation of motion is applied for modeling the deformation waves and zonal disintegration.

Currently, the rate of heading in mines falls short of the capacities of the advanced power-driven machine systems. High-rate mining technology using a robotic travelling module has no parallel and essentially accelerates operation. Determination of operating modes of the module, their checking and visualization is implemented by combining the simulation modeling and computer animation. The models based on specialized software GPSS Studio and Proof Animation enable interactive studies into joint operation of heading machinery and walking powered roof support. The tests provide the estimate of the heading cycle time.

The authors discuss the influence exerted by the structural features of placers and by the distribution of useful components in them on the efficiency of the resource-saving mining. Considering clustering occurrence of gold ore seams, a geometrization error may reach 100% in some areas of operation. The errors of reserve appraisal are defined, and the applicable approaches to mineral exploration, mining and processing control are discussed. In terms of some placers in Yakutia, it is shown that the main causes of errors in gold reserve appraisal include inaccurate determination of the placer morphology and structure, the width first of all, as well as the gold content.

The article gives methodical guidelines for calculating hourly and daily outputs of bucket chain dredgers. The improved output determination procedure is a chain of calculations of dredger performance in correlation with strength characteristics of rocks and with their depth- and width-varied properties. It is proposed to group the mining time and to take into account the action time losses connected with face cutting, dredging within the placer limits, and with breaks for the auxiliary operations. The delays are included via the introduced face cutting factor. It is found how the technical capacity of dredger, the face cutting factor and the dredger utilization per day change as function of the face width at different thickness of placers. The authors put forward an empirical equation for the technical dredger capacity.

The authors propose a new approach to gravity caving of ore in mining with convergent technologies. Based on the ultimate span determination using the stability graph method by Mathews and Potvin among other things, the optimal conditions of gravity ore caving in block rock mass are defined. Structurally, in the operating layer of an ore body, a vertical cut-out is made, and the inclination angles of walls of the outlining and partition backfill masses are changed. The article presents calculation of the Earth’s gravitation field energy accumulated within the dome of natural equilibrium formed in rock mass in the course of mining.

The authors discuss application of nitrogen-oxygen-sulfur heterocyclic agents as collectors and frothers in flotation of sulfide minerals. Efficient collectors are the compounds which contain nitrogen heteroatom and sulfur atom in pendent group: they can generate complex compounds, including chelate, with copper, antimony and other metals in sulfide ore. Compounds containing sulfur heteroatom can modify sulfide surface, which favors attachment of collectors later on.

A new method of acid leaching of kaolin concentrate is assisted with ultrasound cavitation used as a catalyzing factor. This method allows processing of alumina-bearing concentrate without heating of pulp and vacuum degassing of equipment. The lab-scale tests produced aluminum hydroxide at the yield of more than 90% of theoretical value. The process flow diagram is close-loop regarding all consumables.

The phase transitions of sulfide minerals-pentlandite and chalcopyrite-are tested in roasting with mixture with ammonium sulfate. The behavior of the mixture during roasting is assessed via the synchronous thermal and X-ray phase analyses, and by scanning electron microscopy. The basic optimal technology parameters for the efficient processing of sulfide-bearing copper-nickel ore are selected to be: the roasting temperature of 400 °С, the ore:ammonium sulfate ratio of 1 : 10, the particle size of - 40 µm and the roasting time of 240 min. An important condition is joint milling of ore and ammonium sulfate down to the specified size. Given these parameters, the later on water leaching of clinker provided extraction of 94.8% of copper, 91.5% of nickel and 82.3% of cobalt. The research findings are of essential practical interest owing to the high recovery of the target minerals.

The physicochemical research of ammonium fluoride processing of ash and slag waste is performed as a case-study of ash waste of Blagoveshchensk thermal station and fly ash of Amur experimental technology facility. The optimized conditions are determined for some reactions, including fluorination of feedstock in the temperature range of 50-200 °С, sublimation of ammonium hexafluorosilicate at 350-550 °С, as well as production of amorphous silica, fine-grain alumina, red iron-oxide pigment and calcium fluoride. The basic distribution patterns of rare earths, including Sc and Y, during ammonium fluoride processing are determined. The authors have developed the effective innovation technology for various ash and slag waste processing with extraction of ore microconstituents.

The article offers a review of the existing methods to remove suspended solids from industrial wastewater. The mechanical and physicochemical techniques which are in use already and to be in service in the short term are discussed. It is shown that each specific mine needs its own selection of a package of wastewater treatment methods.

In this study, the synthesis of nickel oxalate was investigated from an extract solution of nickel laterite using precipitation method. The experimention determined the best conditions of nickel oxalate synthesis. To optimize the process, Response Surface Method was applied on the experimental data. The kinetics study of the synthesis process shows that the approach using the Avrami model gives a better approach than the first order integral model. The activation energy generated from the kinetics study with this model is 36.5221 kJ/mol.

The authors propose a novel methodological approach to up-to-date integrated satellite monitoring for studying origination of source zones of natural and induced catastrophes at large-scale subsoil use facilities in Siberia. This approach uses multimodal experimental geomechanical and geodynamic data of Earth remote sensing and digital technologies. This allows orientation at various applied aspects of mining technologies with regard to transition to processing and analysis of Big Data on slow deformation wave processes from the standpoint of nonlinear ‘geomechanical thermodynamics’. The article describes the estimation method for the Earth’s crust surface in Kuzbass Coal Basin using the lineament field analysis and the two-dimensional radar-base satellite data of Earth remote sensing. The use of the geoinformation technology software and testing results are presented as a case-study of a disastrous landslide at a large open pit coal mine in linkage with thermodynamic periods in the geomechanical behavior of the object of monitoring.

Slope fracture detection is critical in the safety management of the open-pit mine, and the non-timely detection of slope fractures may cause landslide or other serious consequences. To prevent the unexpected accidents caused by the failure of slope integrity, this paper proposes an intelligent fracture detection algorithm based on improved Mask R-CNN, which can address the limitations of traditional image processing algorithm and the classical deep learning model directly to the open-pit mine slope crack detection. In this paper, we use the integrated features of Mask R-CNN in target detection, segmentation and location, improve the shortcomings of Mask branch, such as unclear edges and false detections, and construct a detection and segmentation framework for slope fracture images of the open-pit mine. This method introduces dilated convolution neural network, and a classify segmentation iterative up-sampling operation into the mask branch, which can solve the problem of slope fracture Mask’s rough edge. Experimental results show that compared with the traditional crack segmentation algorithm, this method has higher recognition accuracy and better segmentation effect.

Methods proposed for mine water treatment use different advanced equipment such as aerators and circular settling tanks which ensure increase in pH and decrease in impurity concentrations by 10-50 times. Passive mine water treatment uses small cascade ponds, which enables additional purification of water due to deceleration in water flow velocity and because of the longer time of interaction between impurities and reagents. The reconstruction of the existing system of three treatment stages can reduce pollution of surface and ground water, which brings essential improvement of ecology and minimizes damage caused to the hydrosphere.