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The experiment with two-frequency radio occultation measurements of the Venusian nightside ionosphere using the Venera-9 and 10 orbiters is described. The experiment is the first of a kind in which the radio link to one of the spacecraft is used to probe the ionosphere, while the other is measuring the variations in the integral electron number density along the path of radio ray propagation. The experiment has been designed to achieve the maximum possible accuracies in determining the parameters of the probed ionosphere using the bistatic two-frequency radio occultation method.  相似文献   
2.
Levels of adenylate metabolism have been studied in cells of Nicotiana tabacum growing in vitro, and in root apex extracts of Pisum sativum irradiated at the 95-in. isochronous cyclotron U-240, Institute for Nuclear Research, Ukrainian National Academy of Sciences, Kyiv. Particle beams of accelerated helium ions with energy 9.34 keV/micrometer were used. Replacement and rapid freezing of the irradiated plants samples in liquid nitrogen were carried out with a manipulator and a remote control system. After doses of 5, 20, 50, and 100 Gy of gamma-irradiation, as well as 50 and 100 Gy 4He irradiation, the cellular ATP/ADP ratio increased during early stages of the response. This effect was absent at higher doses and after exposure to sparesly-ionizing radiation, when a rapid decline in the cellular ATP concentration and the ATP/ADP ratio occurred.  相似文献   
3.
The 3 : 1 mean motion resonance is studied in the planar elliptic restricted three-body problem (Sun-Jupiter-asteroid). Using double numerical averaging, the equations are constructed that describe the secular evolution of eccentricity and perihelion longitude of the asteroid orbit. The region of adiabatic chaos is isolated in the phase space of the system under study.  相似文献   
4.
AVHRR MCSST data for the periods 1982–2000 (mean weekly data) were used to calculate mean gradient fields in the ocean for different periods of time. Three-month averaged sea surface temperature gradients (SSTG) and their mean seasonal variations have been studied for 25 points in the large-scale oceanic fronts zones. Major oceanic fronts in the Atlantic and Pacific have been identified and compared in literature. In the North Atlantic and Pacific, the areas under study were the North Polar Front and Subpolar Fronts. In the South Atlantic and Pacific we studied the region of the Antarctic Circumpolar Current (ACC) and the fronts formed by this current, known as the South Polar Front, and the Subantarctic Front. SSTG were also calculated for El Niño (Southeast Pacific) and Benguela Current (Southeast Atlantic).  相似文献   
5.
On the basis of using of modern methods of cytological analysis the cell growth peculiarities, reproduction and structure of plant cells of different level organisation (unicellular algae, mosses, angiosperms, cell cultures of higher factors--weightlessness, hypogravity, magnetic fields of various intensity, vibration and acceleration were cleared. It is shown that many discovered biological effects of space flight are connected with the degree of complexity of the object organisation and intensified with the increasing duration of influence.  相似文献   
6.
The attitude motion of an artificial satellite carrying a strong magnet is studied. The approximate first integrals of the problem, i.e., adiabatic invariants, are indicated. The basic properties of the satellite motions close to the regular precessions with slowly varying parameters are established via the analysis of the adiabatic invariants.  相似文献   
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