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21.
Using microscopy methods on light and dark fields, the flow patterns developing in drying droplets of pure transparent liquids, solutions, and suspensions of micro- and nanoparticles are investigated. The flow patterns inside drying droplets of real, colloid, and mixed solutions containing nanoand microparticles-markers are studied by means of video and photo registration of microscopic images. The analysis of particle displacements indicates the existence of a global convective flow which forms a toroidal circulation with an ascending jet at the droplet center. The typical types of the structures depending on the droplet composition are distinguished. It is shown that the intensity of the flow inside the droplet affects the surface convection. The effect of the hydrodynamic flow on the transport of a substance, forming the dry-deposit texture, is studied.  相似文献   
22.
Salimov  R. B.  Shabalin  P. L. 《Mathematical Notes》2003,73(5-6):680-689
In this paper, we obtain a generalization of the method of regularizing multipliers for the solution of the Hilbert boundary-value problem with finite index in the theory of analytic functions to the case of an infinite power-behaved index. This method is used to obtain a general solution of the homogeneous Hilbert problem for the half-plane, a solution that depends on the existence and the number of entire functions possessing mirror symmetry with respect to the real axis and satisfying some additional constraints related to the singularity characteristic of the index. To solve of the inhomogeneous problem, we essentially use a specially constructed solution of the homogeneous problem whereby we reduce the boundary condition of the Hilbert problem to a Dirichlet problem.  相似文献   
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The paper presents some aspects of pneumotransport theory of solid ball motion along a pipeline of complex geometry having application for the pelletized cold moderator of the IBR-2 reactor. Motion equations for a ball carrying by gas flow along a round tube both smooth and rough, are obtained. Aerodynamics forces and momentum of forces, acting on the ball depending on its velocity are defined on the base of numerical modeling of ball movement, and analytical simplified model of pneumotransport of balls along round tube is created. This model meets the demand for practical application as it shows satisfactory agreement with experimental modelling of ball movement in a glass tube. One of important results of the work is giving proofs of irregular movement of ball along a tube stipulated by roughness of the tube side.  相似文献   
25.
On the basis of R&D results on laboratory and pilot levels the possibility of production and expansion of “Tomskneftekhim” Ltd. brand assortment of polyolefin plastics with the use of contemporary titaniummagnesium catalysts (TMC) is analyzed. The production results of “Tomskneftekhim” Ltd. polypropylene output, reached due to the use of catalyst systems of I (aluminothermal TiCl3) and II (MSK-TiCl3) generations, and forecasting results for system of IV generation (TMC) are presented in the report. The experimental testing of propylene polymerization kinetic features, raw material quality, and influence of catalyst system composition and conditions of formation on exploitation characteristics of TMC was carried out by the example of two trade marks of TMC. The conclusion was drawn that the realization by “Tomskneftekhim” Ltd. of a complex program of R&D activities for implementation of the IV generation catalyst system in the suspension technology of the polypropylene production will increase the competitiveness of the process.  相似文献   
26.
An SU(3) × U(1) × U(1)′ gauge model of weak and electromagnetic interactions is proposed which satisfies the ΔT = 12 rule for non-leptonic decays of strange particles. The value of neutral leptonic currents predicted in the model agrees with the experimental data.  相似文献   
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The dynamics of an isolated domain wall (DW) with a fine structure moving at a supersonic velocity in a rare-earth orthoferrite is studied. A set of nonlinear equations of motion of the center of a DW structure line is derived. A steady-state solution to these equations adequately describes the experimental data for yttrium orthoferrite. The effect of an external magnetic field on the steady-state velocity of a DW with structural lines is investigated.  相似文献   
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A novel family of nitrogen stilbene analogs, 1-styrylpyrroles, has been synthesized in good to excellent yields by a straightforward facile transition metal-free addition of pyrroles to arylacetylenes in the KOH/DMSO system (90–120 °C, 5–13 h). Thermodynamically controlled E/Z-isomer ratio of 1-styrylpyrroles depends on structure of both pyrroles and acetylenes ranging from ca. 100% E-stereoselectivity (for the pair unsubstituted pyrrole—phenylacetylene) to 90, 96% Z-stereoselectivity (for the pairs: 2-phenylpyrrole—phenylacetylene and 2-(2-thienyl)pyrrole—phenylacetylene, respectively).  相似文献   
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