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Alekseenko V.,Southern Federal University | Alekseenko A.,National Mineral Resources University University of Mines
Journal of Geochemical Exploration | Year: 2014

For the first time the abundances (the average concentrations) of chemical elements are given for the soils of urban landscapes. The figures were established by authors on the base of average concentrations of chemical elements in the soils of more than 300 cities and settlements in Europe, Asia, Africa, Australia, and America. The major part of data (sampling, analyses and their statistical treatment) was obtained directly by authors as a result of special studies conducted for more than 15. years. The concentrations of elements were defined by the spectral, gravimetric, neutron activation and the X-ray fluorescence methods of analyses. The control of sampling and also inner and outer laboratory controls of analyses were carried out. The ordinary and the control analyses were carried out in the certified and accredited laboratories, including arbitration laboratory. The sufficiently numerous published materials of different researchers were also used. © 2014 Elsevier B.V. Source

Vasilyeva M.A.,National Mineral Resources University University of Mines
Key Engineering Materials | Year: 2016

This paper is devoted to improvement of application of a peristaltic transport of heavy high-viscosity materials using magnetically active material. The main problems that arise when pumping these substances are associated with their low mobility and high shear stress. In various countries of the world peristaltic pumps are increasingly used for this purpose. A fundamentally new approach to transportation of liquid and viscous media consists in using magnetic pumps. Heavy oil and highly concentrated slurry tailings mineral resources are non-conductive materials, and as a result, require the active inducement effect on the portion of the material of the working chamber of the direct channel. © 2016 Trans Tech Publications, Switzerland. Source

Dolgiy I.E.,National Mineral Resources University University of Mines
Neftyanoe khozyaystvo - Oil Industry | Year: 2015

Exploitation of high viscous oil deposits requires specific technical and economical solution of oil extraction. Based on the analysis of current practice of high viscous oil extraction in Yaregskoye oil-titan deposit, the author suggested a system of preparation and exploitation of oil deposit by thermo-mining method. Parameters of suggested system and sequence of its realization was justified. The method of coupled extraction of oil and titan from the same layer, which is suggested in this work, let to achieve the designed production level of high viscous oils in shorter term, to decrease the duration of oil extraction from the current part of the layer and to pass to extraction of titan-oil ore in shorter time. The coupled method of high viscous oil extraction and titan ore lets to achieve the high level of oil-titan site preparation for further extraction. The method of oil extraction lets to achieve the ratio of oiltitan extraction coefficient to a number of 90 %. Source

Brigadnov I.A.,National Mineral Resources University University of Mines
Acta Mechanica | Year: 2015

The boundary value problem of small static deformation range is formulated as the variational problem for the displacement. The general local conditions of convexity and rank-one-convexity are obtained for smooth elastic–plastic potentials depending on two first convex invariants of the Cauchy strain tensor. It is demonstrated that all types of convexity are equivalent for the Hencky elastic–plastic potential, but, for example, the strain energy function of continuum fracture can have every type of convexity for different relationships between material parameters. The classical regularization method is applied for the construction of the lower convex envelope of the Hencky strain energy potential for the experimental non-monotonic stress–strain relation with falling part. For this relation, the concept of the Maxwell line is used by analogy with the Van der Waals’ gas theory. The results of 1-D and 2-D numerical examples show that this regularization is principally necessary for the convergence of the finite-difference methods that are usually used for numerical computation within the framework of the small deformation models with non-monotonic stress–strain relations. © 2015, Springer-Verlag Wien. Source

Brigadnov I.A.,National Mineral Resources University University of Mines
Acta Mechanica | Year: 2015

The boundary value problem of torsion of a solid cylinder is analyzed for a class of hyperelastic materials that exhibit the power law type dependence of the strain energy density on the magnitude of the deformation gradient. The Saint Venant hypotheses are generalized by including the non-homogeneous longitudinal and radial deformations. A nonlinear variational problem with respect to the function of the radial/surface deformation, the function of the longitudinal deformation, the normalized torque and the normalized axial force is formulated. The asymptotic analytical solutions are obtained for the hard device torsion and for large angles of twist. They illustrate the power law type dependencies of the axial force and the reaction torque on the angle of twist with the exponents p and p−1, respectively. For Treloar (neo-Hookean) materials with p = 2, the classical results can be obtained. The finite element analysis of the hard device torsion is performed by MATLAB. The results indicate that for a homogeneous class of materials and large angles of twist non-homogeneous radial/surface deformation can be observed. © 2014, Springer-Verlag Wien. Source

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