System environment "Brainstorm" for support of the inherited software

The problem of support of the inherited software, arising at accompaniment of existing applied programs packages is analyzed. Solution of the given problem with the help of system environment «BrainStorm v. 1.0» under MS Windows which allows to create and to accompany software packages which were carried out under MS-DOS is proposed. The basic mechanisms of system maintenance realized in «BrainStorm» are described. Results of testing of the given tool means are given

Theoretical prediction of perfect spin filtering at interfaces between close-packed surfaces of Ni or Co and graphite or graphene

The in-plane lattice constants of close-packed planes of fcc and hcp Ni and Co match that of graphite almost perfectly so that they share a common two dimensional reciprocal space. Their electronic structures are such that they overlap in this reciprocal space for one spin direction only allowing us to predict perfect spin filtering for interfaces between graphite and (111) fcc or (0001) hcp Ni or Co. First-principles calculations of the scattering matrix show that the spin filtering is quite insensitive to amounts of interface roughness and disorder which drastically influence the spin-filtering properties of conventional magnetic tunnel junctions or interfaces between transition metals and semiconductors. When a single graphene sheet is adsorbed on these open $d$-shell transition metal surfaces, its characteristic electronic structure, with topological singularities at the K points in the two dimensional Brillouin zone, is destroyed by the chemical bonding. Because graphene bonds only weakly to Cu which has no states at the Fermi energy at the K point for either spin, the electronic structure of graphene can be restored by dusting Ni or Co with one or a few monolayers of Cu while still preserving the ideal spin injection property.Comment: 12 pages, 11 figure

The experimental data on the density, viscosity, and boiling temperature of the coffee extract

The paper shows the experimental data on the density, viscosity, and boiling temperature of the coffee extract. The mass fraction of the dry substances varies in the range of 15-70 % for all measurements. The coffee extract temperature varies in the rage of 20-80 °C for the density and viscosity measurements. It is found that the coffee extract density varies in the range of 1030-1350 kg/m3 for the considered cases. The coffee extract viscosity varies in the range of 0.0008-27.4810 Pa•s for the considered cases. The coffee extract boiling temperature varies in the range of 100.0-103.3 °C at atmospheric pressure. It was found that the coffee extract is foaming in the considered range of dry substances mass fraction. The foaming temperature is decreasing with the dry substances mass fraction increasing. © 2020 Published under licence by IOP Publishing Ltd

Experimental research of the bovine black albumin spray drying processes

The paper shows the results of the experimental research of the spray drying of the bovine black albumin. The physicochemical properties of the dried bovine black albumin were obtained. The granulometric composition and the particle shape structure of the dried product were obtained for the spray drying using the centrifugal sprayer and the pneumatic sprayer for the various solid content range in the source product and the various drying agent initial temperature. The effect of the spraying method, the drying agent initial temperature and the solid content range in the source product on the dried bovine black albumin particle average size was defined. © 2019 Published under licence by IOP Publishing Ltd

Mathematical Model of Two-Phase Flow Processes in Heat Exchange Tubes of the Falling Film Evaporator

In this work, a mathematical model and a method for calculating the film evaporation apparatus were proposed. The mathematical model provides data on the distribution of hydrodynamic parameters of a two-phase flow along the length of the heat exchange tubes of the evaporator. The obtained data are necessary for the design of an efficient falling film evaporator. © Published under licence by IOP Publishing Ltd

Perturbation theory for the one-dimensional optical polaron

The one-dimensional optical polaron is treated on the basis of the perturbation theory in the weak coupling limit. A special matrix diagrammatic technique is developed. It is shown how to evaluate all terms of the perturbation theory for the ground-state energy of a polaron to any order by means of this technique. The ground-state energy is calculated up to the eighth order of the perturbation theory. The effective mass of an electron is obtained up to the sixth order of the perturbation theory. The radius of convergence of the obtained series is estimated. The obtained results are compared with the results from the Feynman polaron theory.Comment: 9 pages, 2 figures, RevTeX, to be published in Phys. Rev. B (2001) Ap

Modelling of Sediment Mixing Processes During Preparation of Conversion of Scandium Concentrate

Modern methods of computational fluid dynamics make it possible to evaluate the effectiveness of various design options for chemical devices already at the design stage. This work is devoted to the study of the processes of mixing sediment with a high solids content, in the preparation of the conversion of scandium concentrate, using the methods of computational fluid dynamics, based on a previously developed mathematical model. As a result of the work, the parameters of the distribution of the volume fraction of the solid phase were established, and the velocity field of the suspension in the simulated apparatus was investigated. © Published under licence by IOP Publishing Ltd

Graphite and graphene as perfect spin filters

Based upon the observations (i) that their in-plane lattice constants match almost perfectly and (ii) that their electronic structures overlap in reciprocal space for one spin direction only, we predict perfect spin filtering for interfaces between graphite and (111) fcc or (0001) hcp Ni or Co. The spin filtering is quite insensitive to roughness and disorder. The formation of a chemical bond between graphite and the open $d$-shell transition metals that might complicate or even prevent spin injection into a single graphene sheet can be simply prevented by dusting Ni or Co with one or a few monolayers of Cu while still preserving the ideal spin injection property

Investigation of Hydrodynamic Parameters Distribution in Heat Exchange Tubes of Falling Film Evaporator

The purpose of this work is investigation of changes in hydrodynamic parameters (absolute pressure, mass flow rates of solution and secondary steam, secondary steam velocity, solution irrigation density, and pressure loss) along the length of the heat exchange tube of a vertical falling film evaporator. The obtained data of the distribution of hydrodynamic parameters were used in the design of falling film evaporators. © 2021 Author(s)

Investigation of Two-phase Flow Hydrodynamics of Heat Exchange Tube Outlet Falling Film Evaporator

The purpose of this work is investigation the distribution of the gas phase velocity and the liquid phase irrigation density at the outlet of the heat exchange tube of a vertical falling film evaporator. Experimental studies of the hydrodynamics of the two-phase flow at the outlet of the heat exchange tube were carried out on the pilot instalation. Radial distributions of the liquid phase irrigation density at various distances from the lower section of the heating tube are obtained. It is established that high gas phase velocities contribute to turbulization of the two-phase flow in the heat exchange tube and redistribution of part of the liquid phase to the gas flow. © 2021 Author(s)