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891.
V. P. Okhlopkov 《Cosmic Research》2018,56(2):101-107
The quasi-biennial variations in the flux of galactic cosmic rays (GCRs) have been studied based on the data of stratospheric sensing and measurements by neutron monitors, as well as in various manifestations of solar activity and interplanetary medium parameters. It has been shown that quasi-biennial GCR variations are caused by variations with the same period in the mean magnetic field of the Sun that coincide with them over time and have been identified in the anti-phase, which respond to the sign of this field. The variations in the quasi-biennial cosmic ray are caused by quasi-biennial variations in the mean magnetic field of the Sun via the quasi-biennial variations in the interplanetary magnetic field. 相似文献
892.
A. B. Agul’nik I. V. Kravchenko A. A. Gorbunov A. A. Novoselova A. P. Sklyarova 《Russian Aeronautics (Iz VUZ)》2018,61(3):441-444
This paper considers double bypass aircraft engine with controlled air bleed to the second bypass duct. Its performance is evaluated by mathematical modeling techniques. The second bypass air bleed amount is determined to provide the best engine efficiency at various operating modes. 相似文献
893.
The dynamics of a satellite-gyrostat moving in the central Newtonian force field along a circular orbit is studied. In the particular case when the vector of gyrostatic moment is parallel to one of the satellite’s principal central axes of inertia, all the equilibrium states are determined. For each equilibrium orientation, sufficient conditions of stability are obtained as a result of the analysis of the generalized energy integral, and necessary conditions of stability are determined as a result of analysis of the linearized equations of motion. The evolution of regions of validity for the conditions of stability of equilibrium positions are studied in detail depending on the parameters of the problem. All the bifurcation values of the parameters at which qualitative changes of the regions of stability take place are determined.__________Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 4, 2005, pp. 283–294.Original Russian Text Copyright © 2005 by Sarychev, Mirer, Degtyarev. 相似文献
894.
Yu.A. Surkov V.L. Barsukov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(8):17-29
Physical and mechanical properties as well as chemical and mineral composition of Venus rocks are discussed on the basic of the data obtained by ground-based radar observations and the experiments in situ. 相似文献
895.
U. von Zahn V.I. Moroz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(11):173-195
Our current knowledge on the composition of the Venus atmosphere in the altitude range from the surface to 100 km is compiled. Gases that have been measured, and whose mixing ratios are assumed to be constant with altitude, are CO2, N2, He, Ne, Ar, and Kr. Gases that have been identified in the lower and/or middle atmosphere, but whose mixing ratios may depend on altitude, latitude and/or local time, are CO, H2O, HCl, HF, and SO2. Conflicting data or only upper limits exist on some important trace gases, such as O2, H2, and Cl2. The latter two are key constituents in the photochemistry of the middle atmosphere of Venus. The chapter concludes with a listing of the isotopic abundances of elements measured in the Venus atmosphere. 相似文献
896.
N.V. Jorjio R.A. Kovrazhkin M.M. Mogilevsky J.M. Bosqued H. Rème J.A. Sauvaud C. Béghin J.L. Rauch 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(4):141-144
The plasma diagnostic experiments on the AUREOL-3 satellite have revealed flows of low energy 0+ ions deep inside the night plasmasphere during a large substorm. Flux gradients of the 0+ ions were accompanied by enhancements of ELF electric field noise. The appearance of suprathermal ions at is interpreted within the framework of electrostatic ion-cyclotron acceleration of ionospheric ions in the diffuse auroral zone /12/ followed by a radial displacement of these ions inside the plasmasphere driven by azimuthal electric fields during substorm activity. Electrostatic oscillations observed inside the plasmasphere are apparently associated with gradient instability at the sharp boundaries of suprathermal ion flows. 相似文献
897.
V.N. Chelomey 《Acta Astronautica》1984,11(5):269-273
New paradoxical phenomena encountered during experiments with vibrating fluids and solid bodies are reviewed. 相似文献
898.
I V Gribovskaya I A Gladchenko G K Zinenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,18(4-5):93-97
Two methods of extracting mineral elements from otherwise deadlock products of a life-support system are presented. We describe first optimum conditions for recovering elements by water extraction from dry wastes of plants, biomass ash, and solid human wastes after passing them through the catalytic furnace; and, second, we describe acid extracts of biogenous elements by 1N and 2N HNO3 from these products. Ways to use the extracts of elements in plant nutrition are considered in order to increase the extent to which the mineral loop of a life-support system can be closed. 相似文献
899.
A Tani Y Nishiura M Kiyota H Murase N Honami I Aiga 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,18(4-5):251-254
It is possible to cultivate plants under an artificial gravity field generated by a centrifugal device in space. In order to determine an optimal magnitude of gravity, there is a need to investigate the relationship between plant and growth and gravity, including not only reduced gravity but also gravity greater than 1G. A prototype centrifugal phytotron was designed and fabricated in order to investigate the relationship between plant growth and increased gravity. This device enables us to cultivate plants over the long term by controlling environmental conditions in the phytotron such as temperature, relative humidity, CO2 concentration and light intensity. The results of our experiment indicate that plant seeds can germinate and grow even under an artificial gravity which changes sinusoidally from 2G to 4G. 相似文献
900.
P M Sterns L I Tennen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1995,15(3):281-284
The planning and execution of manned and robotic missions to Mars present a wide range of jurisprudential issues. Provisions to prevent the disruption of natural celestial environments, as well as damage to the environment of Earth by the return of extraterrestrial materials, are important components of the law applicable to mankind's activities in outer space, and have been supplemented by scientifically instituted planetary protection policies. However, divergent legal regimes may exist, as the space treaties in force are neither uniform in their provisions, nor identical as to the states which have signed, ratified, or adopted the international agreements. The legal requirements applicable to a specific mission will vary depending on the entities conducting the program and specific mission profile. This article analyzes the divergent international legal regimes together with the factors which will influence the determination of the standards of conduct which will govern manned and robotic missions to Mars. 相似文献