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Changes in the ozone concentration during precipitation is studied on the basis of surface ozone monitoring data in Tomsk and on the Karadag. It is revealed that these changes can be both positive and negative. The maximal ozone content jumps are observed during frontal precipitations. During air mass precipitation, the sign and magnitude of the changes are defined by the daily ozone cycle. The analysis showed coincidence between an increase in the ozone concentration during precipitation with its increase in the daily cycle in 59% of cases in Tomsk and in 63% of cases on the Karadag. The coincidence of a decrease in the O3 concentration during precipitation with the ozone decrease wave in the daily cycle is observed even more often, in 85% of cases in Tomsk and in 79% of cases on the Karadag. Based on the aircraft sounding data, ozone sink from the boundary air layer is observed in some cases when the temperature stratification is changing to neutral in precipitation.

A temperature decrease occurs inside the tropospheric polar vortex during winter, which is reflected in an increase in the Arctic sea ice extent. However, the Barents Sea often turns out to be at the tropospheric vortex edge in winter, where the surface temperature is higher, which leads to a decrease in sea ice extent. Based on the ERA-Interim reanalysis data and the NSIDC satellite data, we show that the Barents Sea ice extent depends on the shape and location of the tropospheric polar vortex from December to February. Based on the example of the polar vortex dynamics in 1997/1998 and 2015/2016 and using the correlation analysis, we show that the tropospheric polar vortex edge can repeat the shape and location of the stratospheric vortex from December to March. Thus, Arctic sea ice loss as a result of a change in the tropospheric vortex edge can occur under the influence of the stratospheric polar vortex in winter.

Optical parametric oscillator based on periodically polled MgO:LiNbO₃ pumped by repetitively-pulsed Tm³⁺:Lu₂O₃ ceramic laser with a fiber-laser pumping was experimentally studied. The average power at the spectral range of 3.7-4.2 mm at the OPO output was 530 mW at the power of 7.9 W of the ceramic laser. The full efficiency of energy conversion from NIR-IR to MID-IR was 6.7% and differential efficiency was 8%. For parametric conversion of two-micron radiation from lasers (for example, on Tm³⁺:Lu₂O₃ ceramics or Ho³⁺:YAG crystals) into the mid-IR range, KTP and KTA crystals with regular domain structures are also promising.

The solution is presented for the problem on oil percolation flow in reservoir at the present and time-varying pressure difference between the injection and production wells. The zone of capillary water blockage in the bottom-hole area is determined. The algorithm is proposed for calculating fluid pressure on the bottomhole by the reading of echosounder installed at the well mouth. The invasion zone of the pressure fluctuations in the reservoir is estimated, and their effect on influence enhanced well production is shown.

The new method is proposed for interpreting data of acoustic emission during initiation and growth of dynamic breakaways. The method is based on the analysis of wave form of the emitted acoustic pulses. Clustering of the pulses by the wave form criterion shows that in the localization zone of strains different-scale processes described with various scaling relations take place. All classes of acoustic pulses obey the power-series amplitude-frequency distribution. The sharp-arrival acoustic pulses posses unaltered scaling relations in the period of nucleation and growth of dynamic breakaways whereas the smooth-arrival pulses demonstrate the nonlinear change in the scaling relations. At the final stage of the dynamic breakaway formation, the proportion and amplitude of acoustic pulses with smooth arrival increase.

The results of physical modeling of deep pit slopes with equivalent materials are presented. The checking calculation is preformed using the limit equilibrium method. The displacements in the model are determined, and the safety factors of stable slopes are calculated at all stages of modeling. The pattern of deformation and failure of pit slopes is analyzed starting from the first manifestations till total instability at different strength characteristics of bedding interfaces. It is found that failure mechanism of pit slopes with seep dip bedding is governed by shear strength of contacts. When the contacts and rock mass have similar strength characteristics, pit slope deforms along a smooth curved sliding surface by the similar mechanism of isotropic slope. In the presence of contacts with much lower strength characteristics than the rock mass strength, the slope deformation has the mechanism of flexure toppling. In an intermediate variant, it is most probable that failure follows the mechanism of bending with subsequent shear of the layers along a curved surface.

The regularities of change in mechanical characteristics of heterogeneous structure of frozen geomaterials depending on grain size composition, temperature, moisture content and density of sample packing are determined. It is found that the major influence is exerted on the shear strength, internal friction angle and cohesion in the samples structurally commensurable with blasted rock mass by temperature, moisture content and packing. In the size range of 10-40 mm of inclusions in a sample, the internal friction angle drops by 2 times while the cohesion jumps by the same value. It is shown that blasted frozen rocks prone to re-adfreezing is a complex medium possessing properties of intact uniform rock mass.

In order to determine the slope stability of an open-pit mine effectively at Dorli Opencast Project-II (Dorli OCP-II) of M/s Singareni Collieries Company Ltd. (SCCL), India, from available geotechnical data, this paper proposes analytical and numerical models. Physico-mechanical properties of the rock materials required for establishing these models were obtained by laboratory tests conducted on core samples taken directly from the mine. In this research, the influence of 6 discriminant factors on the pit stability by changing one-factor-at-a-time (OAT) and keeping all other factors fixed is studied. The study utilizes Limit Equilibrium Method (LEM) based software (SLIDE), Finite Element Method (FEM) based software (RS²) and Finite Difference Method (FDM) based software (FLAC/SLOPE) to analyze the sensitivity of each factor on the Factor of Safety (FoS) of pit slope for high accuracy and validation of models. The results from these methods of analyses are compared and comparison of the outputs of analyses shows a very good agreement with nominal difference (<1%) in the FoS.

The method of determining strength characteristics of rocks subjected to tension is tested; the method is based on processing of data from fracture tests of specimens with axial holes of different diameters subjected to loading along diameter. The test data of specimens of rocks and simulating media in the form of cores with axial holes and fractured along diameter are processed based on the integral strength criterion of Novozhilov. The comparison shows good agreement between the fracture toughness and tensile strength values obtained using the proposed method and in standard measurements.

The problem of finding ways of overcoming antagonistical contradictions between the techno- and bio-spheres in development of mineral resources in the Arctic is discussed. It is shown that one of the main avenues of advancement under these conditions is creation and application of nature-like mining technologies. It is found that the hierarchical peak influence on natural biota destruction in permafrost zone is connected with accumulation of solid mining and processing waste on the ground surface, which predetermines the principate of the closed-cycle circulation of solid in lithosphere within the cluster of a nature-like mining technology. The idea is developed and proposed to accord the functional structure of a mining technology with the internal structure of a cryo-georesource and with relation of its components in space and time.