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911.
G. Efstathiou R.I. Jedrzejewski 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
Application of the cosmic virial theorem to galaxy redshift surveys suggests an open universe - if the dark material is distributed in the same way as galaxies. Here we investigate four redshift surveys. We present new results on the amplitudes of the two- and three-point galaxy correlation functions and we estimate the relative peculiar velocities in the deep redshift survey of Kirshner and co-workers (1983). Next, we review evidence which suggests that dark material is clustered on scales comparable to the optical radii of galaxies. In particular, we use spectroscopic and photometric observations to set constraints on the mass distribution in elliptical galaxies. 相似文献
912.
N. A. Vlasova A. S. Kovtyukh M. I. Panasyuk S. Ya. Reisman E. N. Sosnovets 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1989,9(12):163-170
The data from the synchronous-orbit satellites of the Gorizont series are used to study the dependences of the ion flux variation amplitudes in the synchronous altitude region (the diurnal behaviour) on particle energies and on the form and rigidity of the particle energy spectrum. The proton fluxes were measured in the energy range E 60–120 keV, and the [N,0]2+ and [C,N,0]4+ ion fluxes in the energy range E 60–70 keV/e.
The ratio of the diurnal variation amplitudes of the studied ions is shown to correspond to the similarity of their energy spectra in the E/Q representation. The magnetically-quiet time gradient of the distribution function F(μ,J,L) in the synchronous-orbit region is shown to be (∂F/∂L)=0 for the H+ and [N,0]2+ ions and (∂F/∂L) > 0 for the [C,N,0]4+ ions (at the values of μ corresponding to the examined energy ranges). During magnetically-disturbed periods the inner boundary of the (∂F/∂L)=0 region shifts to lower L and (∂ F/∂L) = O in the synchronous altitude region must be also for the [C,N,O]4+ ions. 相似文献
913.
914.
R.K. Crouch A.L. Fripp W.J. Debnam I.O. Clark P.G. Barber F.M. Carlson 《Acta Astronautica》1985,12(11):923-929
Lead-tin-telluride has been grown in a thermally stable mode (solutally unstable) and in a solutally stable (thermally unstable) mode in a Bridgman configuration. Significant differences in the crystal morphology and the compositional homogeneity have been found between the two configurations. In addition, for the solutally stable configuration, evidence has been found that the flow characteristics in the melt change drastically during the course of the run. 相似文献
915.
J.M. Bosqued Yu.I. Galperin R.A. Kovrazhkin Yu.N. Ponomarev H. Rème J.A. Sauvaud V.N. Angarov A. Gladishev A.K. Kuzmin T.M. Muliarchik J.A. Sauvaud 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(7):81-85
The CESR Toulouse - IKI Moscow particle instrument package aboard the AUREOL-3 satellite consists of a complete set of charged particle spectrometers which measure electron and ion fluxes from 15 eV to 25 keV in 128 steps and in 11 directions. In addition, 4 channel spectrometers (2 electron and 2 ion channels in parallel) allow high time resolution measurements (up to 10 msec) with onboard calculation of auto and cross correlation functions. For higher energies (40 – 280 keV), solid-state spectrometers are used to measure electron and proton fluxes in 4 channels in parallel. In addition, two Geiger counters are used for the determination of the trapping boundaries. Two mass-energy ion spectrometers (1 to 32 A.M.U., 0.02 – 15 keV) are placed with viewing angles which allow a distinction between nearly isotropic auroral proton precipitation and conical beams accelerated in the auroral ionosphere. Auroral and airglow photometry is performed aboard the AUREOL-3 satellite by a set of 3 parallel directed photometers with tiltable interference filters for 6300 Å, 4278 Å and Doppler shifte Hβ emissions. Various modes of energy, angular and mass scanning, correlation function calculation and various Soviet and French telemetry regimes provide the possibility of choosing the sequences of measurements according to particular experimental programs along the orbit. Finally, examples of data from inflight measurements using the above instruments are presented and briefly discussed, showing several interesting features. 相似文献
916.
917.
The construction of a binary timing sequence based on interleaving shorter pseudorandom sequences is proposed and the parameter values giving the minimum acquisition time are found. A comparison is made between the interleaving concept and a previously known scheme. 相似文献
918.
G M Lisovsky J I Gitelson M P Shilenko I V Gribovskaya I N Trubachev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,20(10):1801-1804
Model experiments in phytotrons have shown that urea is able to cover 70% of the demand in nitrogen of the conveyer cultivated wheat. At the same time wheat plants can directly utilize human liquid wastes. In this article by human liquid wastes the authors mean human urine only. In a long-term experiment on "man-higher plants" system with two crewmen, plants covered 63 m2, with wheat planted to--39.6 m2. For 103 days, complete human urine (total amount--210.7 l) was supplied into the nutrient solution for wheat. In a month and a half NaCl supply into the nutrient solution stabilized at 0.9-1.65 g/l. This salination had no marked effect on wheat production. The experiment revealed the realistic feasibility to directly involve liquid wastes into the biological turnover of the life support system. The closure of the system, in terms of water, increased by 15.7% and the supply of nutrients for wheat plants into the system was decreased. 相似文献
919.
A B Sarangova L A Somova T I Pisman 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,20(10):1945-1948
Dynamics of catalase activity has been shown to reflect the growth curve of microorganisms in batch cultivation (celluloselythic bacteria Bacillus acidocaldarius and bacteria of the associated microflora Chlorella vulgaris). Gas and substrate closure of the three component ecosystems with spatially separated components "producer-consumer-reducer" (Chl. vulgaris-Paramecium caudatum-B. acidocaldarius, two bacterial strains isolated from the associated microflora Chl. vulgaris) demonstrated that the functioning of the reducer component can be estimated by the catalase activity of mciroorganisms of this component. 相似文献
920.
Literary and experimental data on the character of changes in immune organs and lymphoid tissue of respiratory system and digestive system in laboratory animals during the mission factors model area given. Inhibition of reproductive function in bone marrow, thymus and spleen under irradiation of gamma-rays and accelerated carbon ions, tensity of immune response in the lymphoid structures of larynx, trachea and bronchi under the influence of acetaldehyde vapors and decrease of lymphoid tissue square on histological series in spleen and small intestine with an increase of concentration of microbial bodies in the drinking water were estimated. 相似文献