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The methodology to determine physical and mechanical properties of granular materials containing coal is substantiated. A set of methods and facilities is developed to find bulk density, cohesion coefficient, internal and external friction coefficients and distributive capacity for ROM coals, coal concentrates and other coal-bearing materials. The laws of change in the listed characteristics within some variation intervals of process parameters are found for the real-life processes of coal flow and storage. The integrated studies and systematization of coal flow process parameters are described.

Selection of efficient methods and means for rock fracture is one of the major challenges the coal mining industry is faced with. For rocks of high hardness, the most efficient fracture method is drilling with button bits. The main objective of the implemented research is determining the actual time of contact between bit buttons and rock and the required time of contact to reach the destructive load with respect to various influences.

The authors analyze the mechanical and process properties of gabbro, diorite, peridotite, serpentine and talc carbonate rocks of the Bazhenov chrysotile asbestos deposit. The hardness metering is performed on the surface of the sampled hand specimens. Their compression and tension strengths are found in the air-dry condition. The interrelations are revealed between the mechanical properties of the test rocks and the hardness meter readings. Using an empirical relationship, the crushability classes of the test rocks are determined. The correlation is found between the hardness meter readings and rock crushability at the test deposit. Finally, it is inferred that the present-day idea of the rock strength-crushability connection is valid both in traditional and express method testing.

Experiments on dried and saturated marble samples were conducted at different loading rates to investigate the influences of loading rate and saturated water on the deformation, strength and brittleness indexes of marble. Strength and deformation, the applicability and variation of different brittleness indexes, and the relationship between elastic strain energy limit and brittleness indexes were analyzed comprehensively under different loading rates. The results show that the strength of marble increases with an increase in loading rate, while elastic modulus decreases and peak strain increases. The influence of loading rate on brittleness was analyzed for seven values of the latter. The results indicate that some of the indexes of brittleness cannot reflect the influence of loading rate. Meanwhile, there are two indexes that can accurately express the variation law of rock brittleness with an increase in loading rate. Moreover, these brittleness indexes increase linearly with an increase in loading rate and exhibit a quadratic function relationship with elastic strain energy limit. A new brittleness index that can comprehensively consider strength and energy is proposed to fully express the effects of loading rate and saturation on rock brittleness. In accordance with the macroscopic failure characteristics of marble, the conclusion that a brittleness index increases with an increase in loading rate was proven correct.

The article addresses peculiarities of solid mineral mining in difficult geological and hydrogeological conditions in eastern Russia. The known methods of preparing wet deposits for their further mining are reviewed. Special attention is given to mineral extraction from deposits in river channels, which is the most expensive process subjected to difficult-to-accomplish ecological requirements. The wet deposits are grouped with respect to possible drainage and opencast mining technologies. Some eco-oriented mining technologies are put forward, with efficient management of natural and manmade resources.

A correlation is found between the pressure pulse amplitude of the power unit of a vibration exciter and the impact energy of the driving piston of an electromagnetic percussion drive as a component of the exciter. The correlation is used to investigate energy characteristics of the electromagnetic drive. It is shown that the energy contributed by the flyback coil to the total mechanical work done by the electromagnetic drive in one cycle is 70-75%, while the energy contributed by the forward run coil is 25-30%.

Eco-friendly method for nitration of aromatic compounds using different solid supports has been successfully reported.

The presented work contains the results of studying the floristic diversity of vascular plants in protected mires in the mountain part of the Sverdlovsk Region (Russia). The studies were carried out on six peat six mires: Shitovskoe, Malinovskoe, Paklinskoe, Moroshechnoe, Severka, Shaitanskoe. The article provides a list of discovered species of vascular plants. In total, 170 species of vascular plants, 10 subspecies and 3 hybrids belonging to 104 genera, 47 families, and 5 divisions were identified in the flora of the studied mires. The leading families in terms of the number of species are Cyperaceae (27 species), Rosaceae (15 species) and Ericaceae (12 species), the leading genera are Carex L. (21 species), Salix L. (9) and Rubus L. (6). A relatively low level of species similarity between the floristic lists of bogs under consideration was revealed. The greatest similarity was noted for the Paklinskoye and Severka mires. Рlurizonal and boreal species with a wide distribution (Holarctic, European-West Asian and Eurasian) dominate in the flora. Among the biomorphological groups, polycarpic herbs are of significant importance (63 %), of which 39 % are rhizomatous plants. In the studied mires, cenopopulations of some rare species included into the Red Data Book of the Sverdlovsk Region were revealed: Juncus stygius L., Corallorhiza trifida Châtel., Nymphaea candida J. Presl et C. Presl, Hammarbya paludosa (L.) Kuntze, Dactylorhiza incarnata (L.) Soó, Dactylorhiza maculata subsp. fuchsii (Druce) Hyl., Goodyera repens (L.) R. Br., Malaxis monophyllos (L.) Sw. and Neottia ovata (L.) Bluff et Fingerh.

In this article we present the results of the study of littoral diatom complexes of Lake Shunet (Republic of Khakassia), which belongs to the drainless meromictic lakes of the arid zone. There are results of complex hydrobiological research on this water body, but the floristic component is not sufficiently studied, so an inventory of taxa is important for replenishing information about the diatom flora of the lake. In samples collected in 2017-2020 in Lake Shunet, we identified 179 species (189 species and intraspecific taxa) of diatoms belonging to 16 orders, 35 families, and 71 genera. The most widely represented families are Bacillariaceae (30 species), Naviculaceae (18), Cymbellaceae (12), Eunotiaceae (10), Mastogloiaceae (9) and genera: Nitzschia (17 species), Navicula (13), Eunotia (10), Tryblionella (8), Gomphonema , Mastogloia , Pinnularia (7 species each). The minimum diversity of diatoms is typical for the plankton of the lake - 25 species and intraspecific taxa, with the dominance of cyanobacteria Planktolyngbya contorta (Lemmermann) Anagnostidis et Komárek. Benthos and periphyton have the same number of species and intra-species algal taxa - 123. Complexes of dominant taxa have the following composition in these communities: Ctenophora pulchella (Ralfs ex Kützing) D.M. Williams et Round, Cocconeis scutellum var. minutissima Grunow, C . euglypta Ehrenberg, C . placentula Ehrenberg, Haslea spicula (Hickie) Bukhtiyarova, Navicula salinarum Grunow, Pleurosigma elongatum W. Smith, Brachysira aponina Kützing, Pseudostaurosira brevistriata (Grunow) D.M. Williams et Round, Surirella striatula Turpin. Diatom assemblages of the lake consist of freshwater, brackish-water and marine taxa, with a relatively high proportion of halophobes likely coming from the stream and deposited on the sediments.

The paper presents the results of a survey of tree plantings in the city of Bokhtar (Khatlon region of the Republic of Tajikistan). About 180 species of trees and shrubs currently used in urban landscaping. Most of them are deciduous trees. However, the main share of Bokhtar trees, which retain decorative qualities for a long time, are evergreen coniferous plants from the genera Juniperus , Pinus , Cupressus , and Thuja . Most of deciduous trees have high decorative qualities, but they are less stable in local climate. These ones create a variety of urban landscapes, but they are more demanding on growing conditions and agricultural techniques, so the areas occupied by these species are much smaller. Exotic fruit trees such as Citrus and palm species need of additional care and protection and have limited use in landscaping of Bokhtar city. We carried out phenological observations, assessed the stability and decorativeness, and developed the assortment of woody plants recommended for landscaping of Bokhtar. It includes 39 promising species combined into 5 groups, in accordance with their biological characteristics and use in landscape design. Optimal propagation methods identified for the most valuable species. Seed propagation recommended for all species except Salix babylonica and Paulownia tomentosa . Vegetative propagation by cuttings of shoots recommended for 11 species of deciduous trees, for coniferous trees - only Thuja occidentalis . Recommendations on the use of trees and shrubs in Bokhtar landscaping take into account the features of the urban landscape, the architectural and planning solution of the landscaping site and its functional purpose. We recommend to plant groups of trees to create large-scale compositions in the architectural space, tall trees for central city streets landscaping, public gardens and parks. Conversely, in residential areas we recommend planting of low-growing trees as protective ones. Trees for boulevards landscaping and along highways must be resistant to exhaust fumes, temperature changes, low humidity and soil compaction.