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921.
M. P. Danilaev S. A. Mikhailov Yu. E. Pol’skii K. V. Faizullin 《Russian Aeronautics (Iz VUZ)》2012,55(2):208-211
In this paper, we formulated the criteria for evaluating the effectiveness of mixing chambers, needed in obtaining polymeric materials with reproducible properties. The results of comparative analysis of organizing the methods for mixing two multiphase flows of oppositely charged particles are presented. This analysis, carried out using CFD programs, shows that the mixing chamber construction in which the flows being mixed are directed at an angle to each other, and additional gas flow inlets are provided in the lateral wall, is the most efficient. 相似文献
922.
本文给出了正态分布单边可靠性经典精确下限的一种新的计算方法及程序。该程序比国标GB4885-85提供的程序能大量节省机时。 相似文献
923.
R.Z. Sagdeev G.G. Managadze A.A. Martinson Yu.A. Romanovsky R.I. Moisya W.K. Riedler M.F. Friedrich T.G. Adeishvily S.B. Lyakhov L.S. Novikov N.A. Leonov T.I. Gagua I.I. Slyusarenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):129-140
This paper describes two rocket experiments “Aelita” with high power lithium plasma injection. The results of onboard magnetometer, massspectrometer, photometer, plasma, corpuscular and ground radar measurements are given. Dynamics and structure of plasma formation are discussed. 相似文献
924.
A new procedure for restoration of the plasma inhomogeneities with improved resolution is suggested. The procedure deals with the double weighted Fourier transform (DWFT) of the observed wavefield in coordinates of both receivers = (x, y) and sources
0 = (x
0, y
0) [1]. Phase increments between the sources and receivers, being found from DWFT representation, can be used for extracting information on small perturbations of the dielectric constant ~(, z) in a way similar to traditional radio tomography. The resulting resolution of the method is close to the diffraction limit = h/D in the horizontal direction and z = (h/D)2 in the vertical direction, where h is the height of inhomogeneities and D is the length of the ground-based receiving system. 相似文献
925.
Avdeev S Bidoli V Casolino M De Grandis E Furano G Morselli A Narici L De Pascale MP Picozza P Reali E Sparvoli R Boezio M Carlson P Bonvicini W Vacchi A Zampa N Castellini G Fuglesang C Galper A Khodarovich A Ozerov Y Popov A Vavilov N Mazzenga G Ricci M Sannita WG Spillantini P 《Acta Astronautica》2002,50(8):511-525
The phenomenon of light flashes (LF) in eyes for people in space has been investigated onboard Mir. Data on particles hitting the eye have been collected with the SilEye detectors, and correlated with human observations. It is found that a nucleus in the radiation environment of Mir has roughly a 1% probability to cause an LF, whereas the proton probability is almost three orders of magnitude less. As a function of LET, the LF probability increases above 10 keV/micrometer, reaching about 5% at around 50 keV/micrometer. 相似文献
926.
The theoretical models of the formation of the three-dimensional quasi-stationary structures of variations of density and electrostatic potential in a multicomponent magnetosphere plasma are considered. On the basis of the perturbation method, we have studied the domains of the parametric space, where the occurrence of nonlinear quasi-stationary ion-acoustic and electron-acoustic structures are possible. For these structures, the velocities of motion along the direction of the magnetic field are estimated, together with the longitudinal and transverse scales with respect to the direction of the Earth's magnetic field. The calculated dependences of the scales l
and l
|| of the structures on the plasma parameters in the three-component plasma allow one to compare the results of the considered theoretical models with new experimental data of measuring the form of soliton structures onboard the FAST, POLAR, and GEOTAIL satellites. 相似文献
927.
舱内航天服散热途径分析 总被引:1,自引:0,他引:1
为分析常压下航天员穿着舱内航天服时的散热性能,6名健康男性青年按二次复合设计分组共进行24人次试验,经分析计算了获得了服装各散热途径的散热率随通风气源参数及人体活动水平变化的数学模型。对影响服装散热性能的因素及服装散热特性进行了分析讨论。 相似文献
928.
ECSS通信标准E-50发展现状简介 总被引:1,自引:1,他引:0
对ECSS通信标准E-50的组成、通信协议及其与CCSDS系列标准的差异和关系进行分析,并结合空间数据通信参考模型的具体应用,介绍该标准的使用方法,提出我国应用与借鉴国际空间数据传输标准的建议。 相似文献
929.
针对以往特种运动器械存在设计理念陈旧、运动功能单一等缺陷,设计了一种能够提高受训人员综合身体素质的多功能训练器械。该器械主要由旋转中心框架、圆形中心框架、防护装置以及电动传动装置等组成,能够进行康复治疗、强化"核心"训练等。通过实际训练验证,该器械性能稳定,使用安全可靠,并且适用于多人施训,省时省力。 相似文献
930.
The basic principles of selecting some design parameters of a lightweight airplane for the contemporary Russian market are presented. Recommendations for selecting these parameters with the service requirements specified are given based on the study performed. 相似文献