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The productivity of filtration systems for dewatering of finely dispersed suspensions can be increased by pulsating overpressure. For suspensions of marine organic‐mineral sediments, press filtration processes were investigated under static and pulsating overpressure. The influence of the static pressure component, the pressure amplitude characteristic, the pressure vibration frequency, and the filtration time on the volume of filtrate were determined. Based on Darcy's law, a model of the filtration process under static overpressure was developed. For pulsating overpressure, the mathematical theory of experiment planning and the statistical data analysis method were used. 相似文献
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The combinatoric and topological analysis and modeling of the self-assembly of the Na26Cd141–hP168 crystal structure (space group Pbcm; a = 5.483 Å, b = 24.519 Å, and c = 14.573 Å; and V = 1895 Å3) are performed using computational methods (the ToposPro software package). Ninety-eight versions of the cluster representation of the 3D atomic network with the number of structural units ranging from four to seven are found. It is determined that polyhedral clusters–precursors C8 = 0@Na2Cd6 and C9 = 0@Na3Cd6 are templates, on the surface of which atomic shells consisting of 38 and 41 atoms are formed. The composition of the two-layer clusters is C46 = 0@(Na2Cd6)@(Na12Cd26) and C50 = 0@(Na3Cd6)@(Na6Cd35). The centers of clusters C46 and C50 are occupied by positions 1a with the symmetry 6/mmm and 2c with the symmetry −6m2. The symmetry and topology codes of the processes of self-assembly of 3D structures from nanoclusters–precursors C46 and C50 are reconstructed. 相似文献
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Phase equilibria of the binary PbO-ZnO and ternary PbO-ZnO-SiO2 systems have been experimentally investigated at 1033–1898?K (760–1625?°C) for oxide liquid in equilibrium with air and solid oxide phases: tridymite or cristobalite (SiO2), willemite (Zn2SiO4), zincite (ZnO), larsenite (PbZnSiO4) and lead-zinc melilite (Pb2ZnSi2O7) covering the ranges of concentrations not studied before. High-temperature equilibration on primary phase or inert metal (platinum) substrates, followed by quenching and direct measurement of the Pb, Zn and Si concentrations in the phases with the electron probe X-ray microanalysis (EPMA) has been used. Liquidus phase equilibrium data is essential for the development of the thermodynamic model. 相似文献
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G. V. Shevchenko 《Automation and Remote Control》2014,75(10):1732-1742
A numerical method to minimize the resource consumption by the linear systems with constant time delay in the system phase states was proposed. Its global convergence to the ?-optimal solution was proved. By the ?-optimal solution is meant the feasible control u(t), t ∈ [0, T], driving the system to the ?-neighborhood of the origin and providing a value of the functional that differs from the optimal one at most by ?. 相似文献