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61.
Results are given of LDA measurements of averaged and fluctuation velocities of glass particles during their deposition in smooth and dimpled narrow pipes. Experiments reveal a decrease in the axial component of averaged velocity of particles and a significant increase in fluctuation velocities of particles during their motion in a pipe with dimples. 相似文献
62.
O. D. Brovko Yu. A. Bublikov I. V. Mezhebovskii S. N. Podgornyi G. A. Polyakov A. S. Popov A. V. Rabinovich Yu. V. Sadovnik 《Russian Metallurgy (Metally)》2013,2013(12):952-956
Direct alloying of steel by chromium-containing briquettes with a cement binder is tested when they are added to a charge in a DSP-3M furnace under the conditions of the Mirgorod foundry from PAOArmaprom (Ukraine). The actual through extraction of chromium is more than 80 rel. %. 相似文献
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66.
A. E. Polyakov K. A. Polyakov R. V. Trykov I. N. Seryakov N. K. Pavlov T. P. Bordovskaya 《Fibre Chemistry》2009,41(4):260-262
A concept for building the structure and studying controllable electrotechnical complexes for manufacturing equipment that
increase the efficiency of saving energy and resources by optimizing the speed regimes is proposed. Selection of the velocity
diagram of transportation, spinning, and winding of synthetic fibres and nonwovens should precede the process study to determine
the optimum regime indexes. 相似文献
67.
This paper treats the singularities of utilization of laser Doppler anemometers for investigation of the structure of heterogeneous
flows of gas with solid particles. Problems are treated that are associated with studies into the behavior of particles moving
in a gas flow, as well as their reactive effect on the parameters of the carrier medium. The procedures developed for monitoring
the accuracy of the results are described. 相似文献
68.
In this paper, we provide an assessment of plantation forests and private land resources potentially available for pine plantation development in 11 southern states of the United States. After a sustained growth for 50 years, plantation forests (softwood and hardwood on both private and public lands) amounted to 18 million ha or 24 percent of all timberlands in these states in 2007. The vast majority of the plantation forests were established on private lands with fast-growing loblolly pines and slash pines. While purposeful hardwood plantations were rare, there were hardwood stands growing on failed pine plantation sites. Using a two-stage Markov land use transition model, we forecast that private forest land in these states will decline about 7 percent or from 66 million ha in 1997 to 61 million ha in 2027, primarily due to urbanization, and that private pine plantations will rise nearly 40 percent from 11 million ha to 16 million ha. Further, growth in pine plantations will decline in coming decades, and states with low population and population growth have the greatest increase in plantations. These plantations, along with other woody biomass, are expected to play an important role in the emerging bio-energy sector. 相似文献
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70.
T. A. Kudryashova S. V. Polyakov A. A. Sverdlin 《Mathematical Models and Computer Simulations》2009,1(4):445-452
An original numerical algorithm for calculating the gas parameters around a reentry vehicle was described and tested. It is based on a system of Quasi Gas Dynamics (QGD) equations and its approximations on hybrid meshes, which suppose adaptive, locally thickening meshes including both rectangular and triangular cells. The results of the calculations on a sequence of condensed meshes for Mach number values of 2, 5, and 12 are presented. These results correspond to well-known data and demonstrate the high efficiency of the algorithm. 相似文献