Home – Home – Jornals – Journal of Mining Sciences 2025 number 1

The parts of the water vapor continuum absorption conditioned by different physical mechanisms are investigated. The difference between the water vapor continuum absorption calculated according to the asymptotic line wing theory and that found from experiment is the sum of absorption by stable dimers and absorption due to some other absorbing objects. This “unidentified” absorption was found for intervals centered at 8800 and 10600 cm^-1. The spectral behavior of the “unidentified” absorption turned out to be similar to that obtained in the case of modeling the continuum absorption by H₂O dimers through the equilibrium constants of the corresponding reactions. The difference in the unidentified absorption curves found by the two methods can be considered a lower limit of absorption by the monomer wings. Among the graphs available in GrafOnto information system, graphs were found that were qualitatively similar to the unidentified absorption. The results can be considered encouraging, but not final, since the system contains only a limited set of substances.

Identifying the types of atmospheric aerosols plays a significant role in evaluating the influence of aerosols on the climate system, identifying aerosol sources, and improving aerosol satellite retrieval algorithms. At present, there are various ways to classify aerosol particles, but most of them do not take into account regional characteristics. Based on the archival data of photometric observations of the robotic monitoring network AERONET in Middle Urals, a version of classification of the main types of aerosol particles is suggested. The classification was performed by the spectral values of the aerosol optical thickness by the method of k -medians. The initial centers of clusters were defined by spectral values of extinction coefficient calculated with MOPSMAP package from the regional aerosol model MUrA and the global model CALIPSO. Five types of aerosols were identified: Dust, Clean Continental (background), Polluted Continental/Smoke, Polluted dust, and Elevated Smoke. Analysis of data showed that Clean Continental and Dust aerosols are most common in the Middle Urals (26 and 25% of observations, respectively), while the presence of Polluted Continental/Smoke accounts for 20%. The suggested approach makes it possible to significantly supplement the information obtained by spectral ground-based photometric measurements.

The article presents the results of aircraft lidar measurements of the spatial distribution of the relative concentration of chlorophyll- a in the surface waters of the Kara Sea. The chlorophyll concentration was determined by the laser-induced fluorescence method. For normalization, the intensity of the Raman scattering signal of water radiation was simultaneously recorded. The results of the spatial distribution of the normalized fluorescence intensity were obtained at three sites in the southwestern region of the Kara Sea. For two sites in the shelf zone near the western coast of the Yamal Peninsula, the spatial distribution of the fluorescence intensity is quite uniform with variation coefficients of 9 and 15%. The third site in the northern tip of the Yamal Peninsula is characterized by a strong influence of continental river runoff, which is manifested in the presence of sharp frontal zones with scales of 5-10 km, where the variation coefficient of the normalized fluorescence intensity Cl reaches 40%. The variation in Cl values in this section is mainly due to the strong variability of the Raman normalization signals and, to a much lesser extent, to the change in fluorescence intensity. Factors influencing the variability of Raman signals are considered. Synchronous in-situ measurements from a ship and remote measurements from an aircraft allowed us to estimate the dimensional calibration coefficient k_Cl = 1.03 ± 0.09 μg/l for the first two sections of the Kara Sea surface water sounding.

The results of microwave observations of ozone in the middle atmosphere at Apatity (67° N, 33° E) in winter 2022/2023, during a period of high solar activity in the 25th cycle, are presented. A mobile ozonemeter with an operating frequency of 110.8 GHz was used in the measurements. The device had a single-sideband noise temperature of 2500 K, which made it possible to track variations in O₃ with a 15-min resolution in the middle atmosphere. Estimates of the ozone vertical profile at altitudes of 22-60 km have been made. These results were compared with satellite MLS/Aura data on the altitude profiles of ozone and temperature. This report discusses the behavior of ozone in February-March 2023. Ozone variations took place during the sudden stratospheric warming (SSW) which occurred in mid-February and was accompanied by an extraordinary increase in the total ozone content (TOC) from 240 to 500 DU. The limits of ozone changes at altitudes of 25, 40, and 60 km are given. The influence of the intense geomagnetic disturbance (storm) on March 23-24 on the daily variation in ozone at an altitude of 60 km is discussed.

One of the indicators of ongoing climate change is the evolution of cloud regimes, both in individual regions and globally. Within this framework, the long-term variability in the structure of multilayered clouds with an optical thickness of less than 15 over Western and Eastern Siberia during the summer and winter seasons from 2006 to 2023 in daytime conditions is estimated based on CALIOP lidar data (CALIPSO satellite). Multilayering refers to the presence of clouds in several levels at the same time located under each other with gaps between them. The applied methodology is based on the use of cloud classification results from daily CALIOP lidar measurements, calculation of seasonal recurrence values for each combination of cloud types in multilayer structure, deriving time series, determining trends, and evaluating their parameters. It was found that the fractions of clouds with different numbers of layers over both regions did not significantly change during the period under study. In Western Siberia, the proportion of double-layer clouds is 68% in summer and 71% in winter, while in Eastern Siberia, 71 and 75%, respectively. The fraction of three-layer clouds reaches 27% in summer and 25% in winter in Western Siberia and 26% and 23% in Eastern Siberia. The fractions of four- and five-layer clouds do not exceed 5% in both regions together and are almost the same in the two seasons. The most frequent combinations in the multilayer clouds over Western and Eastern Siberia were determined. Estimates of linear trends in the fraction of the most frequent variations in multilayer clouds over the period under study are presented. The results can contribute to improving the accuracy of climate models and radiative transfer estimates.

The study of cirrus clouds is currently under close attention since they play an important role in the formation of the Earth’s climate. Their study is mainly conducted through laser sounding of the atmosphere. The interpretation of laser sounding data requires an adequate optical model of cirrus clouds. However, most existing optical models are developed assuming a random spatial orientation of particles, which, according to recent experimental data, is often inaccurate. We suggest an optical model of cirrus clouds which considers the preferential horizontal orientation of particles within a cloud. The model includes ideal hexagonal plates and columns and hollow columns as quasi-horizontally oriented particles. Additionally, the model incorporates hexagonal plates and columns, droxtalls and bullites, irregularly shaped particles, and aggregates of such particles as randomly oriented particles. The results are crucial for developing algorithms of lidar data interpretation when investigating cirrus clouds.

Method for detecting most forms of altocumulus, stratocumulus, and cumulus clouds and their middle (4-7) and high (8-10) amount is proposed. The method is based on statistical analysis of continuous series of measured global horizontal irradiance. Clouds are classified into two classes according to their influence on the heterogeneity of the formed series. The analysis uses the coefficient of variation and the range of sample. Testing of the method showed that cumuliform clouds are detected with accuracy of 94% at sample completeness of 63%, and the cloud amount is assessed with an error of less than 21%.

An integral component of any analyzer is a sensor. Interest in the development of highly efficient sensing elements for detecting various substances in the surrounding atmosphere remains strong. Among many types of sensors, optical sensors capable of operating in laser mode stand out due to their superior sensitivity compared to fluorescent sensors. This study describes the sensory properties of a photo-excitable active waveguide with a polymethyl methacrylate matrix doped with Nile Red dye. The threshold characteristics of the dye laser generation are investigated. Sensitivity is shown for 0.8% carbon dioxide in an argon mixture and 0.8% nitrous oxide in an argon mixture at atmospheric pressure within the active waveguide under lasing conditions. Possible mechanisms for reducing the lasing threshold in the presence of detectable substances are discussed.

Surface inspection under large strains is a critical problem for both civil and mechanical engineering. Optical techniques can be used for its solution. Digital image correlation (DIC) is one of these promising optical techniques. It is used to measure displacement and strain fields without contact with the specimen surface. Input parameters can directly affect the strain field calculation accuracy. The correlation method is a key parameter in strain field calculation based on DIC, especially under large strains. In this work, three spatial and incremental methods are tested; their accuracy and applicability are estimated; their advantages and drawbacks are discussed. The results can be useful for the developments of means for non-destructive testing.

A laser guide star is an essential part of the adaptive optics system of a ground-based optical telescope. The main limitation of sodium laser guide stars, formed on the basis of the resonant fluorescence of mesospheric sodium atoms, is the low brightness of the LGS. To estimate a possibility of creating LGS based on the fluorescence of other metals in the mesosphere, the efficiency of excitation schemes for atoms of potassium and nickel are calculated. The relative backscattering flux of fluorescence for transitions of potassium and nickel atoms is calculated taking into account the content of the atoms in the mesosphere and the transmission of the atmosphere. The comparison with the results for sodium atoms is made. Our results can be used for the development of adaptive optics systems with artificial reference sources for ground-based telescopes and mesospheric lidars.

A laser guide star is an essential part of the adaptive optics system of a ground-based optical telescope. The main limitation of sodium laser guide stars, formed on the basis of the resonant fluorescence of mesospheric sodium atoms, is the low brightness of the LGS. To estimate a possibility of creating LGS based on the fluorescence of other metals in the mesosphere, the efficiency of excitation schemes for atoms of iron are calculated. The relative backscattering flux of fluorescence for transitions of iron atoms is calculated taking into account the content of the atoms in the mesosphere and the transmission of the atmosphere. The comparison with the results for sodium, nickel, and potassium atoms is made. Our results can be used for the development of adaptive optics systems with artificial reference sources for ground-based telescopes and mesospheric lidars.

As a result of a spill and leakage of diesel fuel from storage tanks in Norilsk, oil products entered adjacent water bodies, reaching Lake Pyasino. The objects of the study were nesting and migrating geese, their organs and tissues. An aerial survey was conducted in 2021-2023, and counts in aggregations were made using photographs. For monitoring and establishment of sampling sites, the territory was divided into 4606 squares (1 km²), of which 1205 sites (149 impact sites and 1056 control sites) were identified. After their ranking and species richness analysis, 5 most contaminated and 7 control sites were identified. Nesting birds showed the greatest changes in liver, lungs and heart. Brown-colored foreign particles were present in the blood, diffusely distributed throughout the circulatory system and noted in the blood in all organs under study. At the same time in all groups of birds a pronounced invasion in the organs under study was detected. The studied birds showed disorders of hematopoiesis, venous hemorrhage, edema and hemorrhages in lungs, bronchopneumonia, hypertrophy of cardiomyocytes, fatty dystrophies in parenchyma, focal necroses in liver. The presence of brown-colored foreign particles was observed in the blood. With prolonged exposure to a toxicant there is a transition of the organism from a stress state to a shock state. In this case, free kinins, which are vasoactive polypeptides, play a significant role. Thus, after chronic exposure to petroleum products, pronounced pathologies of internal organs characterized by disorders of hepatobiliary, cardiovascular and respiratory systems were observed. The hypothesis that oil product spills during accidents, as well as their residual presence after territory cleanup are toxic for both nesting and migratory birds of the wetland complex was confirmed. However, pathohistological changes in the liver, lungs and heart are more pronounced in nesting species.

Fire-derived charcoal (charcoal) is a common product of post-fire forest ecosystems. Its role in a litter decomposition is still poorly understood, even less is known about the relationship between charcoal and soil fauna. In a field “litterbag” experiment using physical exclusion of fauna by means of mesh different sizes, the influence of charcoal on microbial activity indices at the early stage of oak leaf decomposition in conditions of faunal community complexity was studied. The response of microorganisms to charcoal addition and faunal community complexity was evaluated using the substrate-induced respiration method in terms of microbial respiration coefficient (BR/SIR) (basal respiration / substrate-induced respiration), microbial metabolic coefficient (qCO₂), and microbial biomass carbon (M_BC). When the faunal community complexity increased from microfauna to mesofauna, regardless of the presence of charcoal, microbial biomass increased by 40 %. In the control treatment, a 21 % decrease in qCO₂ and BR/SIR was observed with access of mesofauna compared to access of microfauna alone. In the charcoal treatment, the decrease in qCO₂ and BR/SIR in the presence of mesofauna was twice as pronounced and amounted to 44 % (p < 0.05), and an acceleration of mass loss by 17 % was also observed. In our study, the decrease in qCO₂ in the presence of mesofauna and its even greater decrease in the charcoal-mesofauna treatment were due to an increase in microbial biomass, but not to an increase in BR. Further complication of the faunal community (access of macrofauna) did not lead to significant changes in microbial activity indices irrespective of charcoal adding.

The paper aims at the dynamics of vegetation and soil properties formed by the primary succession (for about 30 years) in the middle taiga subzone of the European North-East of Russia. By the end of the third decade, the post-technogenic territory practically finished the process of grass-to-forest community replacement with the formation of a dense tree layer, development of soil ground cover dominated with forest and forest edge species. Forest ecosystem means differentiation of separate groups of woody plants (parcels) with the formation of litter: deciduous-coniferous litter in pine parcel and deciduous-grass litter in birch parcel. The grass-to-forest community replacement is accompanied by transition from humus-impregnated humus pelozems to eluviated humic- impregnated pelozems. At the tree stand development stage, soil morphological structure and chemical properties are determined by the parcel structure of forest community. Differences in C_org. and content of biogenic elements in litter and organic-mineral soil horizon are caused by different composition of plant communities in parcels and, consequently, different mineralisation rates of plant residues. By the end of the third succession decade, the upper 0-20-cm soil layer accumulates up to 24.5 t organic carbon /ha in pine parcel and 28.7 t organic carbon/ha in birch parcel.

Our aim was to investigate levels of biologically active compounds and antiradical activity in water-ethanol extracts from the leaves of Siberian species of the genus Caragana [ C. spinosa (L.) DC., C. arborescens Lam., C. bungei Ledeb., C. microphylla (Pall.) Lam., C. frutex (L.) C. Koch, and C. pygmaea (L.) DC.] as a source of medicinal raw material and for chemotaxonomy of these species. The profile of biologically active compounds and antiradical activity of C. frutex are reported for the first time. The leaves of C. spinosa have a high content of catechins (4.88 mg/g). It was shown that the highest concentration of secondary metabolites (tannins, flavonols, and saponins) and high antiradical activity are present in forest-steppe species: C. frutex and C. arborescens . Among all the assayed populations, the highest variation was observed for catechins, and the lowest for saponins. High interpopulation variation of biochemical traits in C. pygmaea was noted (coefficients of variation (%): catechins 119.91, flavonols 74.19, tannins 44.45, and saponins 44.09). Among the analyzed Caragana populations, a correlation was demonstrated between the antiradical activity and levels flavonols (r = -0.61), tannins (r = -0.52), and saponins (r = -0.51). The chlorophyll a /chlorophyll b ratio ranged from 2.3 to 3.8 among the populations, with a median value of 3.0, indicating near-optimal conditions for plant growth. Correlation analysis revealed a positive association between total chlorophyll and carotenoid levels (r = 0.64). The level of pectins among the studied Caragana species varied from 0.7 to 21.7 mg/g, and that of protopectins from 9.0 to 114.0 mg/g. The present paper illustrates substantial antioxidant potential of water-ethanol extracts from Caragana leaves, consistently with high concentrations of phenolic compounds and saponins, and this association was confirmed by correlation analysis. Our results point to potential uses of Siberian Caragana species in nutraceutical and pharmaceutical products and thus offer good industrial applications.

As a result of many years of research in the Barabinsk forest-steppe, the peculiarities of ecology and biology of the damselfly Enallagma cyathigerum were revealed. The species lives in all permanent reservoirs - rivers, river channels, lakes and ponds, where its most numerous populations have been identified, and also inhabits temporary reservoirs, surviving in them during periods of drying out due to the egg phase. Biotopic preferences were found in the choice of habitat: the larvae live only in non-reed hydrocenoses, which is associated with the ecological standards of the species. In the last 20 years, there has been a decrease in the number of E. cyathigerum, despite the increase in humidity in the region, which we associate with the consequences of climate warming - weather disasters in the summer, an increase in air temperature and, accordingly, water in reservoirs, leading to a deterioration in the hydrology of reservoirs and suffocation of aquatic organisms. A study of the development of E. cyathigerum on Kargat River and Fadikha Lake in 2004-2006 revealed a one-year life cycle of a species that has a different population structure on a river and lake associated with their different hydrological and temperature regimes. The species population on the Kargat River was unified in all 3 years, on Lake Fadikha in high-water 2004 it was unified, and in low-water 2006 it was divided into 2 seasonal groups - summer with wintering larvae and summer-autumn with wintering eggs. Such a complication of the population structure on Lake Fadikha in 2006 was the result of an increase in water temperature (as a result of an increase in the average daily air temperature and a decrease in the water level in the lake), and is a kind of “adjustment” of the species to the deterioration of habitat conditions in the low-water period: eggs are present in the lake almost all year round (wintering and non-wintering) and the larvae have different ages, and imagoes fly on land from spring to autumn. This adaptive feature of E. cyathigerum may partly explain its relatively high abundance, eurybiont and large range - almost the entire Palearctic.

Based on the results of computer modeling of the Altai-Sayan endemic species Euphorbia pilosa L. (Euphorbiaceae) distribution in Western Siberia, where the main part of its range is located, areas of accumulation of species registration points were identified that largely coincide with the climatic optima of the forecast model. A set of variables with a high contribution to the forecast model was established, including the long-term average monthly precipitation in August (14.1 %), the amount of precipitation in October (13.4 %), the seasonality of surface air temperature (11.4 %) and the long-term average monthly precipitation in May (10.7 %). The contribution of climatic variables characterizing the amount of precipitation significantly, more than twice, exceeds the contribution of climatic variables characterizing surface air temperature. In contrast, the total contribution of bioclimatic indicators is noticeably, more than 1.5 times, higher for air temperature indicators than for precipitation indicators (18.7 % versus 8.6 %). According to the forecast model, one of the well-defined climatic optimums is located at the northern limit of the species distribution in Western Siberia, in the vicinity of Tomsk. To identify the ecological features of the range within the Tomsk climatic optimum, a model site characterized by the highest predicted values of the probability of the species presence was selected. Using the method of latitudinal and longitudinal bands, sites with a relatively high number of species registration points were identified, and sites with the most favorable climate were determined based on the values of the probability of the species presence indicator. The obtained results are correlated with the possible impact of anthropogenic load within the boundaries of the Tomsk urban agglomeration, where deforestation in areas allocated for gardening associations and societies, construction of linear suburban and suburban infrastructure facilities (highways, railways, etc.) leads to changes of the phytocenotic confinement of the species and fragmentation of parts of its range at the northern limit of distribution in Western Siberia.

The influence of ground lichens Flavocetraria cucullata and Certraria laevigata on chemical, biochemical and microbiological characteristics of permafrost soils of Central Yakutia was studied. It was revealed that the values of the content of organic carbon, exchangeable cations and anions, and pH did not depend on the presence or absence of lichens on the soil surface. It was revealed that the main secondary metabolites of F. cucullata were usnic, lichesteric, protolichesteric and allo-protolichesteric acids, and C. laevigata - fumarprotocetraric acid. Chromatographic analysis of soils revealed the presence of only usnic acid in humus samples under F. cucullata and adjacent areas without vegetation. It was shown that as F. cucullata moved away from the place of growth, there was a decrease in the content of usnic acid and an increase in the content of specific compounds that could be biomarkers of fungi in the soil. Analysis of fungi and bacteria in soils, performed using the cultural approach, showed an abundance of fast-growing micromycetes and bacteria. According to the metagenomic analysis, the taxonomic diversity of fungi in soils was incomparably higher than according to the cultural studies, and mycorrhizal basidiomycetes were the predominant ecological group. Ectomycorrhizal basidiomycetes are primarily susceptible to the effect of lichen F. cucullata. The allelopathic effect of C. laevigata on the soil microbiome is much less pronounced. It is assumed that usnic acid synthesized by F. cucullata diffusely spreads and accumulates in the soil, selectively suppressing the growth of ectomycorrhizal basidiomycetes.

The state of urban forests of natural origin, which is the most important component of improving the ecological environment of a large city (Irkutsk, Eastern Siberia), has been studied. The condition of forests was assessed based on a set of parameters of trees, soil, and herbaceous cover. The impact of aerotechnogenic pollution on forests is shown, it was determined by the accumulation of heavy metals in the assimilation organs of forest-forming species (Pinus sylvestris, Larix sibirica, Betula pendula) and horizons of soil profiles, as well as by the amount of suspended particles of solid aerosol (Particulate Matter, PMx) adsorbed by needles/leaves. The degree of recreational load in urban forests was judged by the violation of the morphological, physical and pedochemical properties of the forest litter and upper soil horizons. A number of negative changes in the parameters of trees have been identified - the level of crown defoliation can reach 50-65 %; the photosynthetic volume of the crowns decreases by more than 2 times; photosynthesis productivity decreases (maximum) by 35-48 % compared to the background; other physiological and biochemical parameters of pine, larch, and birch also change. The herbaceous cover in the forests is sparse, the projective cover averages 60 %, the share of ruderal species averages 44 %. Negative processes were also found in the soil - destruction of forest litter, decrease in aeration, moisture content, violation of acid-base, cation exchange, humification properties. The results indicate that most of the surveyed urban forests are polluted and subjected to recreational pressure. When summarizing the data obtained from field and laboratory studies, a complex of correlating highly sensitive indicators characterizing the state of urban forest biogeocenoses was identified.

The results of an anatomical description of a cross section of a shoot of Juniperus oblonga M.Bieb are presented., affected by Arceuthobium oxycedri. The anatomical structure of a healthy shoot of J. oblonga was compared with the description of the stem of J. communis L. according to literature data, and distinctive features in the structure were noted. It was noted that shoots of J. oblonga are affected by A. oxycedri up to 12 years of age. The depth of penetration of the haustorium depends on the age of the affected shoot; when young shoots are affected, the connection of the haustorium with the xylem is detected up to the perimedullary part of the pith. The haustorium is pointed towards the center of the stem and expanded towards the crustal part and joins the xylem obliquely towards the apex of the stem. At the base of the arceutobium shoot, at the site of its penetration into the juniper bark, “root cups” are formed. n the shoots of J. oblonga affected by A. oxycedri, in the places of penetration of haustoria, the shoot xylem grows, which is the result of activation and synchronization of the work of the cambium of the host plant and the haustorium of the semi-parasite. The growth of xylem occurs due to an increase in the number of layers of the early spring part of the xylem of the stem. The connection of the xylem and phloem of the juniper stem with the conducting system of the hemiparasite is carried out through disjunctive fragments of the haustorium. Each above-ground shoot of Arceutobium has its own haustorial system, not connected with other shoots, which enters the bark part of the stem and rests on the “root cup”. By eight to twelve years of life of the juniper stem, the ectophytic part of the semi-parasite system is destroyed, only “root cups” remain on the surface of the juniper bark, and excessive thickening of the shoot stops.

The results of an experimental study of the rising process of a cluster of monosize drops of isoparaffin oil in an water-glycerol solution in the presence and absence of surfactant at the interface are presented. The flow for the Reynolds numbers range Re=0,01÷1 was studied. The effect of initial volume concentration of drops in a cluster on the rising dynamics was evaluated. New experimental data on the drag coefficient for a cluster of monosize drops uprising in a liquid with/without surfactant at the interface were obtained.

The effect of peripheral flow swirling in a cylindrical channel on the local flow structure and heat transfer in a turbulent gas-droplet flow was numerically studied with variations in the initial mass concentration of water droplets in the range M_L1 = 0 - 0.1 and the initial droplet diameter d₁ = 10 - 100 μm. It is shown that adding droplets leads to a significant increase in heat transfer (more than 2.5 times) in comparison with a single-phase swirling flow. The heat transfer patterns in gas-droplet flows with and without swirling are qualitatively similar. The effect of heat transfer intensification due to gas-droplet flow swirling reaches 50% at M_L1 = 0.1. Initially, with an increase in the droplet size, a significant intensification of heat transfer in the swirling flow occurs. The maximum heat transfer is obtained at d₁ ≈ 50 μm for all swirling intensities of the two-phase flow. Then the value of heat transfer decreases and its dependence on the droplet size becomes more gradual.

Laminar flows of a gas-dust medium with chemical reactions in an axisymmetric tube are studied in much detail in numerical experiments. The study is performed for non-oxidative reactions of catalytic synthesis of hydrocarbons from methane. The hot walls of the tube warm up a two-phase flow of methane and catalytic nanoparticles. Heating of this flow ensures endothermic conversion of methane into hydrocarbons and hydrogen. It is shown that the presence of catalytic nanoparticles in the tube, which activate heterogeneous-homogeneous reactions, leads to significant deviation of the two-phase medium flow from the Poiseuille flow of a single-component gas due to changes in the medium volume and its viscosity. The change in the heat regime along the tube with a change in the thermal conductivity of the reactive medium is investigated. Calculations are performed for various values of the wall temperature, particle concentration, laminar flow velocity, and other parameters. It is found that the medium velocity and the gas component distributions in the volume and at the tube outlet are most strongly affected by the methane activation energy on the surface of the catalytic nanoparticles, particle diameter, and particle concentration.

In a bubble flow, both proper turbulence of liquid and pseudo turbulence induced by the bubbles are present. Total two-phase turbulence of the flow is simultaneously determined by the interaction of these two components. The experimental values of the average friction stress and its pulsations obtained by eight double electrodiffusion friction sensors located uniformly in one section along the pipe perimeter are presented. The gas phase is represented by monodisperse bubble mixtures with average diameters of 1 and 2 mm and a volumetric gas content of up to 20%. To modify the Reynolds numbers for a bubble, two working solutions with different viscosities were used. The average flow velocity of liquid did not exceed 1 m/s. Flow regimes with deviations from the Sato hypothesis on the additivity of pseudo turbulence and proper turbulence of liquid were detected. At transitional Reynolds numbers of the flow and small Reynolds numbers of a bubble, total turbulence is determined by pseudo turbulence, and there is no the influence of singe-phase turbulence.

The presented research has made progress in describing sea spray and understanding the associated processes in terms of its physical properties, as well as the resulting fluxes from the ocean to the atmosphere, its influence on the development of ocean storms, and related problems and issues. The main results were obtained during laboratory experiments on wind-wave channels using high-speed photography. Descriptions of studies related to the identification of the dominant type of spray generation (the "bag-breakup" type) and the statistics of these phenomena in a wide range of conditions depending on the wind-wave Reynolds number characterizing small-scale processes are given. Convolution of this statistics with the droplet size distribution from a single phenomenon of spray generation of the specified type, obtained from data from a special experiment, yields the spray generation function.

Based on the previously developed method for constructing the equation of state (EOS) for liquid and vapor, the thermodynamically consistent analytical equation of state for liquid and gaseous nitrogen (in the molecular phase) is obtained. While constructing the equation of state, the Mie-Gruneisen form was used as a sum of potential and thermal components for pressure and internal energy. The potential components are described by a potential of the Born-Meyer type. For the thermal components, a simplifying approximation is adopted that follows from the condition for the constant average heat capacity and the dependence of Gruneisen function on the volume. When deriving the equation of state for nitrogen vapor and liquid phases, the tables calculated from equations approximating experimental data on isothermal compressibility, adiabatic speed of sound (including the critical region and phase equilibrium line) were used. The obtained equation of state for nitrogen can be useful in studying the phenomena associated with the processes of nitrogen evaporation and condensation in multiphase flow. This modeling takes into account the interfacial heat and mass transfer under conditions of low pressures and cryogenic temperatures.

The density and thermal expansion coefficients of the Li₂Ca intermetallic alloy were measured in the temperature range of 284 - 906 K for the solid and liquid states by means of sample irradiation a narrow gamma-ray beam. The density jump of the Li₂Ca intermetallic alloy was also measured during the solid - liquid phase transition. Data on the thermal properties of the alloy above room temperature were apparently obtained for the first time. A table of recommended values of the thermal properties of the Li₂Ca alloy over the entire measurement range is presented and their errors are estimated. It is confirmed that the Li - Ca melt with a calcium content of 33.33 at. % is an almost ideal solution.

A direct stastistic modeling method was applied for simulation of dynamics for a “gas - dust particle” system within the problem of study for near-core gas-dust atmopshere of a comet. The paper considers the gas-dynamic mechanism of dust particle ejection from the comet core surface. This assumes the esistance of a dust-coated cavity which is filled by sublimation products from the ice-core components. Calculation offers the data on dust particle velocity as a fuction of key parameters. The ejection velocity for a dust particle is described by one general parameter.

Results of an experimental study of gold-induced crystallization of thin films of amorphous germanium (a-Ge) are reported. The Raman spectroscopy and optical microscopy are applied to study the influence of the initial thickness of the a-Ge film on the morphology of the material obtained by means of annealing of bilayer Au/a-Ge structures. The a-Ge/Au thickness ratios equal to 1.1 and 2.3 are considered. Low-temperature annealing in quartz/Au/a-Ge samples is performed in a high-vacuum atmosphere (10^-4 Pa) at a temperature of 300 °С for 24 h. The Raman spectroscopy results show that annealing of the samples results to complete crystallization of a-Ge with formation of polycrystalline germanium (poly-Ge) in both lower and higher layers of the samples. For the sample with a-Ge/Au = 2.3, a continuous poly-Ge film is obtained on the substrate owing to implementation of the layer exchange mechanism. In this case, poly-Ge hillocks are formed in the upper layer of the sample due to a-Ge crystallization in the presence of Au. For the sample with a-Ge/Au = 1.1, a non-continuous poly-Ge film with a coverage ratio of 30% is formed in the lower layer. The poly-Ge material is formed in the upper layer owing to the processes of “explosive” crystallization and also secondary crystallization induced by Au.

A possibility of using non-monochromatic photodetectors capturing radiation in a wide range of wavelengths as sensors of the brightness channel in spectral brightness pyrometry is considered. A definition of the effective wavelength of the pyrometer is introduced on the basis of the dependence of the detected signal on the temperature of the heat source. Experimental results on determining the effective wavelength of the photodetector with the sensitivity in the interval of 400 - 1100 nm in recording the temperature lamp radiation in the temperature range from 1557 to 2494 K are reported.

The paper presents the results of dilatometric measurements for thermal expansion of monocrystal silicon for the temperature range of 100 - 1373 K. The temperature dependencies for thermal properties of material are calculated. The look-up tables for a broad range of temperatures for a solid material are calculated.

A boundary value problem is formulated for the stress-strain modeling of rock mass with regard to nonlinear deformation of rocks in the influence zones of mine roadways. Different variants of boring patterns for the directional hydrofracturing of hard roof, such that reduce the risk of geodynamic events in longwall mining of flat coal seams, are discussed. Numerical modeling shows that the most effective variant is arrangement of an initiator-notch in the seam roof in parallel to natural bedding in coal-rock mass. It is found that initiators-notches ensure a substantial decrease in roof rock displacements above production faces because of stress relaxation in rocks between induced fractures and coal seam. This effect grows when the length of an initiator-notch is increased to 10-20 m.

The article describes numerical investigation of usability of fracture propagation pressure in stress assessment of rock masses. Development and testing of the proposed approach involved 3D numerical experimental modeling of hydraulic fracturing nearby a cylindrical cavity. The main equations in the model were solved using the extended finite element method. The patterns of variation in the fracture propagation pressure nearby the cylindrical cavity are obtained. The relations are presented to find stresses in uniform compression and in a nonuniform field when the minimal stress acts in perpendicular to the axis of the cavity. It is studied how the error of the method changes depending on the ratios of the model parameters. It is shown that in some cases, it is possible to assess direction of the minimal stress by the hydraulic fracture trajectory, its exposure and propagation pressure.

Using the discrete element method, the scalar and vector properties of a granular medium subjected to loading along two-link broken trajectories are analyzed numerically. The calculations of loading samples of a granular medium by cyclic alternating shear and broken trajectory shear are performed. The issue of the value of Ilyushin’s delay trace is discussed. Based on the dilatancy analysis, the trace of delay in the scalar properties of a medium is estimated. The delay in the vector properties is assessed by comparing the stress and strain tensor components during loading. It is found that the trace of delay in the scalar and vector properties in granular media is higher than in metals by one-two orders of magnitude.

Rockburst hazard of mining operations under an open pit bottom at Sayak-1 deposit is assessed. Mining practices use the room-and-pillar system down to a depth of 295 m below the pit bottom. At the present time, pit bottom rock mass of the Central Sayak deposit holds reserves mostly in ore pillars. Single events of dynamic behavior due to the action of rock pressure were recorded in the course of mining. The strength and deformation characteristics of rocks are determined in a laboratory environment. It is found that core samples are prone to rockburst hazard. The natural stresses at the deposit are measured using the hydraulic fracturing method. RQD index of rock mass is determined. The rock mass is of fair and good quality. The average uniaxial compression strength of rocks is 95.85 MPa. By Kaiser’s criterion, rockburst hazard is absent at the deposit and dynamic failure events are unlikely as a consequence. For all rockburst-hazardous types of rocks at the deposit to the depth of 295 m, the coefficient K characterizing rockburst hazard is lower than the critical value. The level of the maximal stresses induced by mining operations is insufficient to provoke dynamic events in rock mass.

The article describes the research findings on slope stability in open pits and quarries Transbaikalia, at the stages of exploration, mine planning, design and redesign. The feature of the test surface mines is tectonic disturbance of rock masses, including zones of faulting, crushing and compression. Earlier, such geomechanical assessment was carried out using traditional approaches, and the conclusions lacked estimates of probability of slope failure in open pits. Modern regulations on pitwall stability recommend quantitative estimation of slope failure probability using the probabilistic analysis and statistical testing, for example, the Monte-Carlo method. Owing to the statistical testing and its results, it is possible to quantitatively assess probable risks of slope failures in open pits and, also, to offer better defined requirements on the input data accuracy.

The authors used numerical modeling and physical simulation techniques to study influence exerted by the discontinuity zone width in rock mass and by the size of a crushed rock fraction on the parameters of ground penetrating radar signals. The discontinuity zone represented a layer with rough boundaries. The correlation is found between the measurement error of such layer width and the size of the crushed rock fraction.

In order to study the formation mechanism of the high-cold and high-altitude mountain collapse disaster caused by underlying complex goaf group, the lithology, occurrence of structural planes in rock mass and hydrological conditions of overburden in goaf were obtained through field investigation. Combined with the field investigation results, the landslide disaster mechanism was comprehensively analyzed. The stability of the mountain slope in the underlying goaf and the potential slip arc surface of the collapse body are analyzed by the two-dimensional finite element analysis method. The main causes of surface collapse of mountain slope are: the steep structural plane of rock mass, rainfall and fissure water erosion, freeze-thaw cycle, underground ore body mining disturbance, etc. Geological conditions are the internal cause, while underground mining is the inducement. The combined action of the internal and external causes leads to the special formation mechanism of collapse.

Transition from the specific energy analysis to optimizing process variables in drilling and blasting is discussed as a case-study of the Koktasjal copper-porphyry deposit. The proposed rock hardness determination procedure, as compared with the same-purpose laboratory testing, provides preventive information on rock mass, in real time and without significant expenditures, which is beneficial for practical problem solving, in particular, drilling and blasting optimization and control. Adjustment of a mass blast project in block no. 18-19 at Terekty Mining and Processing Plant is carried out. The powder factor was calculated per each blasthole using the conventional approach and the proposed procedure with regard to the specific energy of drilling. The experimental research with the determination of the drilling specific energy as an optimization criterion of drilling and blasting yielded a positive result and a substantial economic effect. The saving totaled more than 10% of the overall explosive amount put in the mass blast project. The quality of rock fragmentation by blasting was improved as well, which was favorable for the performance of the crushing and sizing facilities.

The authors substantiate the use of the cushion blasting method and decoupled explosive charges to soften large-block (pebbly alluvium) permafrost rock mass at open pit coal mines in the cryolithic zone of Russia’ Far East. The key feature of the method is the decoupling of a borehole charge with separate initiation of the top and bottom portions at a delay not less than one day. This allows an artificial quasi-greenhouse effect owing to blocking of detonation products of the bottom charge. The introduction of the method at the Bureya Open Pit Mine in the Khabarovsk Krai ensured reduction of the powder factor more than by 1.5 times, increased underdrilling of up to 2 m to the design bench toe and enhanced level of safety due to a larger volume of mass blasts over 2 times.