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931.
Using power resources of the outer space and its industrialization have become an urgent task in the development of present day civilization. Solar energy is the most suitable basis for power supply for the majority of projects in the near-Earth space. Passing on to the large-scale space-based systems of power supply requires putting into life demonstration experiments in which power transmission by electromagnetic emission is supposed.In the paper the expedience of developing an autonomous power module which provides the possibility of space programs with great power consumption and wireless transmission system running-up is proved. Ukraine can design a solar power satellite of 10–20 kW power on the basis of the research satellite AUOS-SM. Two variants of design solutions for such satellite with solar arrays of great area are presented. Power transmission to the space vehicle-consumer can be conducted by cable as well as in a wireless way. The possibilities of placing microwave and laser energy transmission systems on board the satellite are analysed. It is shown that a power supply system for space vehicles with transmission distance of thousands km can be designed basing on modern lasers.Some experiments making use of great electric power generated by the plant of the satellite under consideration are proposed. The running-up of electric thrusters which are necessary for orientation and distancing is of great interest. Wireless power transmission may be carried on to a small satellite equipped with electric thrusters. 相似文献
932.
Ionic conductivity in poly(vinyl butyral) based polymeric electrolytes: Effect of solvents and salts
Li+ conductive solid polymeric electrolytes (SPEs) have been prepared by complexing Li salts LiX (X = I, SCN, CLO4, CF3SO3) with poly(vinyl butyral) (PVB) an amorphous polymer with a low Tg value and well known for its outstanding laminating properties. These self-supporting SPEs have been prepared by the solution cast technique using cyclohexanone, tetrahydrofuran, and n-butyl alcohol as solvents. The XRD and DSC investigations correlated to measured ionic conductivities have revealed that in addition to the amorphous nature of the resulting complex, its Tg value, the concentration and the values of the lattice energies of the complexing salts, the solvent used in making the SPEs also govern the value of ionic conductivity. Highest ionic conductivity values attained in SPEs made with n-butyl alcohol are explained in terms of the interception of the hydrogen bonding due to solvation. 相似文献
933.
934.
This article considers a discrete sequential multilevel automated system for recording electron-diffraction patterns. A comparative
analysis is presented, along with experimental results that make it possible to evaluate the effectiveness of the technical
decisions on which the device is based. The general design of the system is presented.
Translated from Izmeritel'naya Tekhnika No. 5, pp. 16–18, May, 1996. 相似文献
935.
NIKIÉT. Translated from Atomnaya Énergiya, Vol. 75, No. 4, pp. 265-269, October, 1993. 相似文献
936.
V. P. Titov 《Powder Metallurgy and Metal Ceramics》1994,32(11-12):911-912
The solubility of tungsten in iron has been determined at 1560–1620°C by successively saturating molten iron with tungsten while ensuring a uniform distribution of the content over the height. The temperature dependence of the solubility over that temperature range is described by a Schröder equation: Cs=(3.94±0.11)×103e-(84.4±0.4)/RT. 相似文献
937.
V. F. Prisnyakov Yu. D. Morozov A. N. Privalov 《International Journal of Heat and Mass Transfer》1994,37(18):3015-3020
Experimental results on void fraction and friction pressure drop in vapour-potassium flows in the high-vapour-quality region up to unity are presentéd. The experimental data obtained and the pertinent results of other authors are generalized, and empirical relationship are suggested to calculate void fraction and pressure drop in two-phase liquid metal flows for channels of various configurations and orientations. The relationships are valid within the range of vapour qualities from almost zero to unit. The experimental data prove the mass velocity to have no influence on the hydrodynamic characteristics within the range of the parameters investigated. It is found in the experiments with heat supply that friction pressure losses are smaller than those for adiabatic conditions. It is shown that this result is in good correspondence with the model of the effect of injection in a boundary layer on the value of shear stresses between cases. 相似文献
938.
939.
G. I. Leibengardt A. S. Naidenov V. L. Fedorin V. L. Shur 《Measurement Techniques》1993,36(7):763-766
A two-wave laser interference refractometer for measuring the refractive index of air, pure gases, and gaseous mixtures is described. An algorithm for calculating the results of measurements using the method of coincidence of fractional parts of the orders of interference is given.Translated from Izmeritel'naya Tekhnika, No. 7, pp. 29–31, July, 1993. 相似文献
940.
I. P. Borovinskaya T. P. Ivleva V. E. Loryan K. G. Shkadinskii 《Journal of Engineering Physics and Thermophysics》1993,65(4):988-990
A mathematical model of dissolution of gas in a metal is suggested with account of phase formation in accordance with the phase constitution diagram (PCD). The stage-by-stage saturation process to the final product formation is shown for an individual particle, through which a reaction wave passes, depending on the diffusion permeability of the metal and solubility conditions that obey Sieverts's law. The effect of the filtration supply of the oxidant to the reaction zone and the process exothermicity on the course of the process is shown.Institute of Structural Macrokinetics, Russian Academy of Sciences, Chernogolovka, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 4, pp. 447–450, October, 1993. 相似文献