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841.
An upgraded system for controlling pneumatic transportation of glass batch materials produced by the Stromizmeritel' JSC is considered. Comparative analysis of various schemes of control over the process of filling the pneumatic-cell pump with material is provided. 相似文献
842.
843.
The structure and phase composition of the samples of foam aluminum based on the AMg6 alloy (Al-6%Mg-0.7%Mn) obtained in a high-energy planetary mill are investigated. Mechanical doping provides high dispersity and homogeneity of all structural components including particles of the foam agent TiH2, which allows one to obtain foam aluminum with a pore size of 1–5 mm at a density of 1.20–0.80 g/cm3. Mechanical properties of foam aluminum were estimated based on the results of compression tests. Based on preliminary investigations, an imitation model of foam formation is suggested that well describes the process of foam formation. 相似文献
844.
O. V. Anfalova A. I. Vorob’ev V. S. Kraev M. A. Chemerkin L. I. Osokin 《Atomic Energy》2006,100(6):389-393
The construction and basic technical characteristics of the TUK-84 assembly are described. The materials used to fabricate
the vessel parts and sealing components are presented, and the composition and operation of the system which monitors the
technical parameters are described. The construction of the rolled layers (courses) is discussed and their advantages are
shown.
__________
Translated from Atomnaya énergiya,Vol. 100, No. 6, pp. 419–422, June, 2006. 相似文献
845.
B. I. Anan’ev 《Journal of Computer and Systems Sciences International》2007,46(3):391-398
The problems of constructing recursive relations for conditional and unconditional distributions of random informational sets are considered. These sets, which are called multi-estimates in the paper, appear naturally in the problems of estimation of states and parameters of multistage stochastic inclusions. 相似文献
846.
Methods and algorithms of numerical simulation for three-dimensional thermal-convective motions of the inhomogeneous high-viscosity incompressible fluid in the direct and inverse time are described. In contrast to the direct-time problem, the inverse-time problem is ill-posed; to solve it, one of the variants of the quasi-reversibility method is used. The main attention is focused on the organization of effective computing processes on parallel-action computers. As an example, simulation results of the inverse problem of restoration of development history of thermal mantle plumes are given. 相似文献
847.
The testing procedure and the results of tests performed on a 19-element fragment of a VVéR-1000 fuel assembly in the channel
of a MIR reactor under conditions of the second and third stage of a maximum anticipated accident are presented. The state
arising in the reactor core with an uncompensated leak arising in the first cooling loop when a pipeline with the maximum
diameter bursts (large leak) is studied in the experiment. In each case study, superheated steam cools the top part of the
fuel elements. The main goal of the tests is to obtain data on the distortion of fuel-element cladding under tensile stresses.
__________
Translated from Atomnaya énergiya, Vol. 103, No. 5, pp. 286–291, November, 2007. 相似文献
848.
I. V. Kudryavtsev V. N. Rychkov V. I. Skorokhodov B. K. Radionov S. S. Naboichenko 《Russian Journal of Non-Ferrous Metals》2007,48(3):191-193
Interaction of cobalt(II) ions with functional groups of sorbents based on amines, which additionally contain carboxyl (ANKB-35) and hydroxyl (SB-1, AN-31) fragments, is investigated. It is shown that the form of existence of the sorbent exerts an insignificant effect on cobalt absorption with ampholyte ANKB-35. Alternatively, anion exchangers AN-31 and SB-1 sorb cobalt in noticeable amounts only in the deprotonated form (OH?). The analysis of obtained results on the cobalt sorption in equilibrium conditions as well as the IR spectroscopy provides clarification of specific features of the process. It is found that cobalt is adsorbed owing to the complex formation with nitrogen of amino groups of sorbents with the additional formation of bonds with carboxyl (ANKB-35) and hydroxyl (AN-31, SB-1) groups. In addition, the process is complicated by precipitation in the phase of sorbents according to the scheme Co2+ → Co(OH)2 → Co(OH)3. This effect is especially characteristic of the SB-1 anion exchanger, which contains a considerable amount of hydroxyl groups. The obtained data provide a justified choice of the ion exchanger and conditions of its use to concentrate Co2+ from solutions of sulfuric acid leaching of various cobalt-containing raw materials. 相似文献
849.
InAs channel field-effect transistors of 1-μm gate length were grown by molecular beam epitaxy and observed to operate at channel electric fields (20 kV/cm) higher than previously demonstrated and several times greater than the threshold for impact ionization in bulk InAs. Voltage gains on the order of 10 were observed with transconductances as high as 414 mS/mm and output conductances as low as 33 mS/mm. These voltage gains are comparable to those of GaAs-based devices and are the highest observed for InAs channel devices. The results demonstrate the potential for practical room-temperature operation of InAs FETs 相似文献
850.
I Sylvester AF Suffredini AJ Boujoukos GD Martich RL Danner T Yoshimura EJ Leonard 《Canadian Metallurgical Quarterly》1993,151(6):3292-3298
We recently found that normal human sera contain IgG antibodies against two chemoattractants, neutrophil attractant protein-1 (NAP-1/IL-8) and monocyte chemoattractant protein-1 (MCP-1), as well as immune complexes of these proteins. Intravenously administered LPS was reported to cause a sharp rise in serum NAP-1 concentration. Our study was designed to determine if LPS also caused an increase in MCP-1 and to measure associated changes in concentrations of antibody and immune complex. LPS caused a rise to peak within 2 to 3 h in serum concentrations of free NAP-1 and MCP-1, followed by an almost equally rapid fall toward base-line levels by about 5 h postinjection. MCP-1 concentration in sera from the 11 subjects rose to a peak of 330 +/- 52 pM. The peak value for NAP-1 was 80 +/- 11 pM. In 10 of the 11 subjects, free IgG autoantibody to MCP-1 decreased from a mean pre-LPS value of 1820 +/- 660 pM to a mean low of 53% of the respective initial values. Corresponding data for IgG anti-NAP-1 were a pre-LPS concentration of 216 +/- 7 pM, which decreased to a mean low of 44% of the respective initial values. The finding in some subjects of a rapid rise in free antibody after the nadir suggests the possibility of acute regulation of autoantibody secretion rates. Although the results suggested that LPS-induced chemoattractant combined with free antibody, serum concentrations of MCP-1-IgG or NAP-1-IgG did not increase, which points to an as yet unknown mechanism for trapping and elimination of the immune complexes. 相似文献