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On the basis of numerical simulation of optical radiation in a turbulent medium the influence of the value of the topological charge of the optical field on the beam wander and the intensity fluctuations of focused Laguerre-Gaussian beams is investigated. The beams are considered with different values of the topological charge of the complex field and the same radius of the initial aperture. The beams have different diffraction divergence which provides spatial separation of the radiation on the receiving aperture, thereby reducing the influence of different communications channels to each other during the signal demultiplexing. It was found that the beam wandering does not depend on the value of the topological charge of the complex field, and the behavior of the intensity fluctuations is determined by the mean intensity profile, which depends on the strength of the optical turbulence.

In the framework of geo-information model of coal deposit and open pit mine, the author derives analytical expressions for calculating work of rock transportation from face to start point of transport incline, considering road characteristics obtained in the course of geo-information modeling. Alternative calculations of freight turnover and transportation work to overcome gravity and road adhesion are analyzed. The example of calculations for the conditions of a particular open pit coal mine contains comparison of one- and two-flank mining schemes.

The theoretical proof is presented for absolute coal bed methane release as a nonlinear extremal function of production face output. The article givers actual and theoretical evidences of reduction in absolute coal bed methane release under high-rate advance of production face.

Using the Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), microscopy and microhardness test methods, the change in the crystalline and chemical properties and in microhardness of rock-forming minerals of kimberlites as a result of exposure to high-power nanosecond electromagnetic pulses (HPEM) has been studied. Based on the data of FTIR and XPS, non-thermal effect of HPEM results in damage of surface microstructure of dielectric minerals due to formation of microcracks, surface breakdowns and other defects, which ensures effective weakening of rock-forming minerals and reduction in their microhardness by 40-66%.

The current technologies of mineral mining, processing and beneficiation require introduction of water circuiting. A common ecological and technological objective is in this case reduction of concentration of copper and commercial-grade fat acid ions that worsen flotation. A promising way of reaching the set objective is preliminary mixing of different waste water flows with maximum concentrations of the specified ions. The thermodynamic calculations justify optimized water treatment modes when engineering-and-economic performance of copper-molybdenum ore dressing remains unaltered, consumption of fresh natural water is lowered, and water supply is enhanced.

Using proprietory method, the authors have obtained flotation agent BO-extract of atomized leaves and stalks of Heracleum sosnowskyi , and analyzed its composition. Qualitative tests, thin-layer chromatography (TLC), ultraviolet spectrophotometry and flotation tests show that aqueous and organic extracts contain substances that differ in chemical and process properties. The article gives test results for aqueous, alcoholic and aqueous-alcoholic extracts BO used as modifiers in chalcopyrite and pyrite flotation. Selective properties of aqueous and aqueous-alcoholic extracts BO are characterized. The highest depression ability relative to pyrite is a characteristic of aqueous BO extract obtained at pH = 3, with heating and treatment in ultrasonic bath. Organic extracts contain mostly furocoumarins, aspic oils and resins, and have no material effect on flotation activity of pyrite.

The article reports tests on studying mechanism of interaction between modified chlorine solutions and gold-bearing sulfides. The change in texture, structural properties and elemental composition of sulfides after electrochemical treatment is analyzed. The authors indicate basic negative factors reducing dissolution velocity of sulfides.

The analysis focuses on collecting ability of easily desorbed (ED-forms) ethyl and butyl xanthates. The authors give visual proof of “dry” spot extension on mineral surface when xanthates that are active relative to air-water interface are desorbed from it. It is shown that ED-forms of agents, being products of interaction between xanthates and heavy metal salts, can remove water from film between mineral particle and air bubble. The main force on water in the film is conditioned by surface tension nonuniformity at the moment of local rupture and by surface pressure of molecules in the film of agent ED-forms. The collecting ability of ED-forms of xanthate is determined as the rate of its influence on water in the film. The forces exerted on water in the film of ED-forms of ethyl and butyl xanthates are estimated numerically. The dependence of volumetric water flow from the film on the surface tension of agent ED-forms active at air-water interface is found. It is shown that collecting ability of an agent is dependent on surface tension of solution of its ED-forms and is governed by structure of hydrocarbon fragment of the collector.

The article describes the integrated method and results of deformation-wave monitoring of temporal lining in rail tunneling in complex geological conditions on the south of Western Siberia. 3D geometric parameters of temporal lining are measured by laser scanning at a span of 3 months, which enables comparing actual 3D models of temporal lining and rocks in reinforced tunnel section. Based on the data obtained at various times of observation, shifting of unmarked points of temporal lining and deformation of tunnel walls and arch was determined. High density scanning allows remote identification of comparatively small zones where structure of rocks and state of lining are changed. The authors analyze seismic vibration of rocks under hammering, which shows that peak spectral densities of elastic wave in rocks are conditioned by low-frequency (pendulum) wave generated at siltstone and coal interface, and are related with dimension of joints and with mechanical properties of rocks.

The article describes engineering designs of dilatometer to measure transverse deformation in borehole subjected to internal pressure exerted through impermeable shell. The device is equipped with the robotized system for advance along the borehole without special sectional barrels. Functionality and capacities of the dilatometer are optimized for surveying in long directional drill holes in mines.