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781.
The Soyuz 22 space cabin atmosphere was studied for volatile organic trace contaminants. By gas chromatography the following constituents were identified: methane, ethane, heptane, methanol, ethanol, n-propanol, acetaldehyde, acetone, ethyl benzene. Except for acetone, concentrations of the above compounds were close to the values determined in the mock-up experiments.  相似文献   
782.
This paper is a review of nonlinear theory of ELF waves propagating along the magnetic field in the magnetosphere. The following subjects are covered: (1) Main peculiarities of the Quasi-linear Approximation. (2) Nonlinear interaction of monochromatic waves with the resonant particles. (3) Side-band instability. (4) Quasimonochromatic wave packets. (5) Effects due to the inhomogeneity of the medium.  相似文献   
783.
MHD-flow during melting of a spherical metal sample under contactless positioning by alternating magnetic field produced by two circular turns with currents, is investigated. It is shown that when the currents supplying the turns are opposite in direction, electromagnetic forces, originating from the interaction of the Foucault currents with alternating magnetic field, induce two torus-like eddies in the interior of the molten metal drop.  相似文献   
784.
It is shown that decline of spherical albedo of Venus toward the ultraviolet can be explained by the presence of two absorbing agents: a) SO2, for which abundance is 1011 cm?3 at height 68 km and scale height is about 1 km; b) some unknown aerosol absorbent, possibly a 1% FeCl3 admixture in a sulfuric acid concentrated solution. A mechanism of aerosol formation is proposed.  相似文献   
785.
By means of a statistical analysis of the rotational properties of asteroids, we define a class of large amplitude and short period objects (LASPA). A possible interpretation of their collisional evolution and present physical status, in terms of ellipsoidal figures of equilibrium, is proposed.  相似文献   
786.
Gaillard  F.  Bouhifd  M. A.  Füri  E.  Malavergne  V.  Marrocchi  Y.  Noack  L.  Ortenzi  G.  Roskosz  M.  Vulpius  S. 《Space Science Reviews》2021,217(1):1-28
Space Science Reviews - Accretion onto black holes is an efficient mechanism in converting the gas mass-energy into energetic outputs as radiation, wind and jet. Tidal disruption events, in which...  相似文献   
787.
Possible mechanisms of solar-climatic connections, which may be of importance as over short and long time intervals, are discussed. The variations of energetic balance of Earth's climatic system for the last fifty years are estimated. It is ascertained that the disbalance between the flux of solar energy that comes to the Earth and radiates to space is of 0.1% for the last ten years. The suggested mechanism makes it possible to explain not only the observed variation of the enthalpy of the Earth's climatic system for the period 1910-1980, but also the climate anomalies during last thousand years: the climate optimum in 12 century, and"small glacial period" in 16-17 centuries.  相似文献   
788.
A restricted 2?+?2 body problem is proposed as a possible mechanism to explain the capture of small bodies by a planet. In particular, we consider two primaries revolving in a circular mutual orbit and two small bodies of equal mass, neither of which affects the motion of the primaries. If the small bodies are temporarily captured in the Hill sphere of the smaller primary, they may get close enough to each other to exchange energy in such a way that one of them becomes permanently captured. Numerical simulations show that capture is possible for both prograde and retrograde orbits.  相似文献   
789.
Results of the optical observations of Mercury and the Moon confirm the close similarity of photometric properties of the bodies. Undoubtedly, the surface of Mercury, which is subjected to the same processes, is covered by a mantle of shattered rocks – the regolith. The structure of the reflecting layer determines the photometric and polarization characteristics of the surface of a planetary body. Despite the general similarity of the integral optical properties of the surfaces of Mercury and the Moon, specific characteristics of the media of these celestial bodies manifest themselves as identifiable differences in the details of the measured parameters: Mercury’s regolith is smoother than of the Moon, probably contains a greater fines fraction, and has greater maturity.  相似文献   
790.
In the present work the possibility of the fractal analysis application for GRB temporal profiles was studied. We have analysed the 4B revised BATSE catalog: temporal profiles of GRB with t90 < 3 s (287 short and 100 intermediate) were studied on TTE data, a sample of 278 intermediate GRB with t90  3 s were studied on DISCSC data. An analysis of the background fractal dimension distributions obtained using TTE and DISCSC data (143 and 110 background regions, respectively), indicates that for both datasets background fractal dimensions Dbgr = 1.5 that the fractal dimension distributions obtained by using these data can be processed simultaneously. The change of the fractal index Dbgr for Poisson statistics – dominated sets with different coefficients of error in counting (up to 10) was studied and Dbgr = 1.5. The ranges of fractal dimension (0.80  D  2.25 for short and 0.85  D  2.01 for intermediate GRB) are shifted over range for theoretical fractal curve (1 < D < 2) due to the finite detector time resolution. There are four subgroups in fractal dimension distribution for short GRB (D = 1.05 ± 0.03, D = 1.31 ± 0.05, D = 1.51 ± 0.04, D = 1.90 ± 0.03) and six subgroups for intermediate one (D = 1.05 ± 0.09, D = 1.24 ± 0.08, D = 1.44 ± 0.07, D = 1.51 ± 0.08, D = 1.64 ± 0.07, D = 1.91 ± 0.1). Time profiles with fractal dimension smaller then background can be obtained by using models with many short chaotic processes in sources, for example, fireball model with shock waves. The range of fractal dimensions for the modelled temporal profiles is 1.213  D  1.400, which can correspond to subgroups of short and intermediate GRB with D = 1.31 and D = 1.24; moreover, the fractal dimension of a simulated indented event and GRB990208 are equal within the error limits for some model parameters and it is possible to obtain smooth temporal profiles with D = Dbgr.  相似文献   
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