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211.
This instrument is designed to make measurements of the full three-dimensional distribution of suprathermal electrons and ions from solar wind plasma to low energy cosmic rays, with high sensitivity, wide dynamic range, good energy and angular resolution, and high time resolution. The primary scientific goals are to explore the suprathermal particle population between the solar wind and low energy cosmic rays, to study particle accleration and transport and wave-particle interactions, and to monitor particle input to and output from the Earth's magnetosphere.Three arrays, each consisting of a pair of double-ended semi-conductor telescopes each with two or three closely sandwiched passivated ion implanted silicon detectors, measure electrons and ions above 20 keV. One side of each telescope is covered with a thin foil which absorbs ions below 400 keV, while on the other side the incoming <400 keV electrons are swept away by a magnet so electrons and ions are cleanly separated. Higher energy electrons (up to 1 MeV) and ions (up to 11 MeV) are identified by the two double-ended telescopes which have a third detector. The telescopes provide energy resolution of E/E0.3 and angular resolution of 22.5°×36°, and full 4 steradian coverage in one spin (3 s).Top-hat symmetrical spherical section electrostatic analyzers with microchannel plate detectors are used to measure ions and electrons from 3 eV to 30 keV. All these analyzers have either 180° or 360° fields of view in a plane, E/E0.2, and angular resolution varying from 5.6° (near the ecliptic) to 22.5°. Full 4 steradian coverage can be obtained in one-half or one spin. A large and a small geometric factor analyzer measure ions over the wide flux range from quiet-time suprathermal levels to intense solar wind fluxes. Similarly two analyzers are used to cover the wide range of electron fluxes. Moments of the electron and ion distributions are computed on board.In addition, a Fast Particle Correlator combines electron data from the high sensitivity electron analyzer with plasma wave data from the WAVE experiment (Bougeretet al., in this volume) to study wave-particle interactions on fast time scales. The large geometric factor electron analyzer has electrostatic deflectors to steer the field of view and follow the magnetic field to enhance the correlation measurements.  相似文献   
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213.
In the 18.5-day flight of the Soviet biosatellite Cosmos-936 (3-22, August 1977) com-parative investigations of the physiological effects of prolonged weightlessness (20 rats) and artificial gravity of 1 g (10 rats) were carried out. Throughout the flight artificial gravity was generated by means of animal rotation in two centrifuges with a radius of 320mm. Postflight examination of animals and treatment of the flight data were performed by Soviet scientists in collaboration with the specialists from Bulgaria, Czechoslovakia, the German Democratic Republic, Hungary, Poland, Rumania, France and the U.S.A. During the flight the total motor activity of the weightless rats was higher and their body temperature was lower than those of the centrifuged animals. Postflight examination of the weightless rats showed a greater percentage of errors during maze an increase in water intake and a decrease in diuresis; a fall of the resistance of peripheral red cells; an increase in the conditionally pathogenic microflora in the mouth; a decrease of oxygen consumption, carbon dioxide production and energy expenditures; a drop in the static physical endurance; a decline in the capacity to keep balance on the rail; an increase in the latent period of the lifting reflex, etc. The centrifugal animals displayed lesser or no change of the above type. These findings together with the biochemical and morphological data give evidence that during and after flight adaptive processes in the centrifuged rats developed better.  相似文献   
214.
Modular pallet-type structures, designed for optimal usage of the Space Shuttle as a launch vehicle, can be used in three mission modes—Shuttle-attached, attached to an orbiting Power Module, or as fully autonomous free flyers. The requirements for such structures are defined and three structural solutions—the Spacelab pallet, a cubic framework structure and a honeycomb panel structure—are described. System and subsystem concepts of varying complexity and autonomy are indicated and their applications to several typical payload examples are shown.  相似文献   
215.
The paper has presented a study of the dependence of the H+ ions concentration in the plasmasphere on geographic longitude. A vast database of measurements of the cold plasma density by the Alpha-3 instrument on board the INTERBALL-1 satellite has been used for the study. Based on these measurements, a dependence of the H+ ions concentration in the filled magnetic flux tube in the plasmasphere in the equatorial plane under quiet geomagnetic conditions has been obtained as a function of geographic longitude. Studies have been performed for two seasons, summer and winter. It has been shown that, during the summer in the near-midnight sector, the minimum in the H+ concentration falls within geographic longitudes of 270°–315°. The ratio of the concentration of H+ ions at various longitudes could reach a factor of three. During the winter, in the near-noon sector, the maximum of the H+ ions concentration falls within longitudes of 180°–225°, whereas the concentration ratio could reach a factor of 2.2.  相似文献   
216.
In August, 1981, the Westerbork Synthesis Radio Telescope was used for 4 h to search for narrowband pulsing radio beacons in the direction of the Galactic Center. By using both the spatial discrimination and temporal stability available to an interferometric measurement, weak intermittent signals can be detected even in the face of the strong, naturally caused radiation from this region. A radio beacon within our bandwidth, centered on the 21 cm neutral hydrogen line, would be recognizable if it had a repetition period between 40 sec and 1/2 h. The rms sensitivity to point sources was approximately 50 mJy/cycle, and the detection limit was 500 mJy/cycle. The limit degrades for pulse widths < 0.02s. No repetitive signals were found. For a swept, narrow-band radio beacon constrained to the Galactic Disk (beamwidth = 0.02 rad), our detection limit corresponds to a transmitter power of 10(11) MW at the Galactic Center.  相似文献   
217.
Cytos 2 experiment, carried out during the French-Soviet manned flight (July 1982), has studied the antibiotics sensitivity of bacteria cultivated in vitro during the orbital flight. The results show an increase of the antibiotics resistance and a larger thickness of the cellular envelope for the inflight cells. The increase of antibiotics resistance can be related to a stimulating effect of space on the cell growth rate or to changes of the cellular envelope structure.  相似文献   
218.
Complex honeycomb space structures (i.e. antennas, solar panels, etc.) must be inspected and accurately tested before flight.The thermography can be employed with success for the detection of the position of defects (delaminations, noneffective bondings, cracks, etc.) and for the evaluation of their size and geometry in all the cases in which the defect acts as a thermal resistance due to the low conductivity of the air filling the defect volume.The basic idea is to create in the specimen a heat flow distribution that is altered by the presence of the defect.The surface temperature distribution is then measured by means of a thermograph and is correlated with the presence of the defect.A numerical analysis and preliminary experiments have been carried out which show the feasibility of the method as applied to honeycomb structures.  相似文献   
219.
The COSAC (Cometary Sampling and Composition Experiment) onboard the Rosetta mission is a combined gas chromatograph (GC)-mass spectrometer (MS). It is situated on Philae, the lander of the mission, which is intended to land on the nucleus of comet 67P/Churyumov- Gerasimenko. The purpose of the experiment is to analyze the volatile fraction of soil samples retrieved by a drill. For investigation, the samples will be pyrolysed, and the emanating gases fed into a GC, into an MS, or the combination of both. In the first part of this paper, the bioastronomical relevance of such measurements is outlined. In the second part the details of the hardware and its performance are described.  相似文献   
220.
For estimating radiation risk in space flights it is necessary to determine radiation dose obtained by critical organs of a human body. For this purpose the experiments with human body models are carried out onboard spacecraft. These models represent phantoms equipped with passive and active radiation detectors which measure dose distributions at places of location of critical organs. The dosimetric Liulin-5 telescope is manufactured with using three silicon detectors for studying radiation conditions in the spherical tissue-equivalent phantom on the Russian segment of the International space station (ISS). The purpose of the experiment with Liulin-5 instrument is to study dynamics of the dose rate and particle flux in the phantom, as well as variations of radiation conditions on the ISS over long time intervals depending on a phase of the solar activity cycle, orbital parameters, and presence of solar energetic particles. The Liulin-5 dosimeter measures simultaneously the dose rate and fluxes of charged particles at three depths in the radial channel of the phantom, as well as the linear energy transfer. The paper presents the results of measurements of dose rate and particle fluxes caused by various radiation field components on the ISS during the period from June 2007 till December 2009.  相似文献   
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