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This paper presents the results of sound velocity measurements performed in natural uranium during the high-rate deformation of sound in α- and γ-phase regions, as well as in the melting region at the shock front. The processes are recorded using the manganin sensor method (range 20 ÷ 110 GPa) and the indicator method (range 70 ÷ 260 GPa). In the region of the solid uranium phase, changes in Poisson's ratio, Young's modulus, bulk modulus, and shear modulus along the uranium shock adiabat are determined.

The article presents the integrated research into geomechanics and geodynamics of Small Tulukui uranium ore field in southeastern Transbaikalia. The studies into tectonic structure and the terrain morphometry in the area of the Steltsov ore field reveals the modern geodynamics features and their correlation with the stress-strain behavior of rock mass. The stress field parameters and the physical/mechanical properties of rocks point at potential of dynamic fracture in the edge area of the deposit. The numerical stress-strain modeling and in-situ observation data prove the tendency of rock mass to rockbursting, and the bottom levels of the deposit (at the depth of 500 m and downward) are assessed as rockburst-hazardous. A package of measures aimed to prevent rock bursts and to reduce geodynamic risk is developed for the mining safety.

The authors describe the dilatancy testing of granular media composed on similar spherical particles-glass balls, millet grains and peas. The testing included simple shearing and complex loading with continuous rotation of the strain tensor axes. The cyclic deformation enables partial elimination of defects of the initial stochastic packing and promotes its transition to a reversible state. The optimal relative density of a packing is presented for the discrete element analyses.

The authors discuss the numerical and field research findings on seismic radiation of water flow in a fracture. The flow parameters can be remotely controlled using the amplitude-versus-frequency response of the vibrations recorded. It is recommended to include the infra-low frequency control in the seismic monitoring in hydrodynamically hazardous mines.

3D discrete-element modeling is used to analyze passive pressure applied by dense soil to a retaining wall. The soil particles have spherical shapes with the radii selected from the normal distribution. The calculation of tangential forces between the particles takes into account the sliding friction and rolling resistance. The surface roughness of the retaining wall has influence on localization of shear strains in the granular medium and on the pressure applied to the wall by the granular material. The calculation results are compared with the classical solution of the limit state theory.

The damage to the surrounding rock under the adjacent explosive load generally manifests as fracture growth. In order to in-depth understand the fracture growth law and mechanism, fracture growth process in the surrounding rock with a nearby adjacent tunnel under the explosive load is studied using the dynamic caustics method. Test results indicate that the original fracture growth process can be divided into two stages, demarcated when the main fracture penetrates the original fracture. The original fracture grows in the vertical direction due to the free surface of the tunnel in the first stage. The main fracture from the explosive source plays a dominant role in the growth direction of the original fracture in the second stage, and the original fracture deflects and grows parallel to the main fracture. Based on kinematic and energy analysis, the penetration process is companied by energy transfer and superposition. The neglected back-facing side also contains fracture on the lower side. The fracture growth direction changes after the original fracture penetrates the free surface of tunnel under the combined effect of the original fracture and unloading wave.

High mountain, locally endemic plant species potentially vulnerable in the context of global climate change are singled out for the mountain systems of the Altai-Sayan Ecoregion.

Features and results of application of biomorphological approaches for the decision of problems in plants introduction are considered. As examples heterogeneous objects, mainly herbaceous, was chosen: large polymorphic genera complexes of moderate warm and tropical origin ( Salvia and Begonia species), and also economic valuable group of ornamental annuals from Asteraceae family.

Rhythms of seasonal development and introduction peculiarities of species and forms of P. mollis Wulfen ex Hornem. and P. saccharata Mill. were studied. Valuable ornamental forms from Novosibirsk and Tomsk regions were described.