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351.
Cloud amounts data of a five year period manually digitized from meteorological satellite imagery are used for cloud statistics over the European region. Spatial and temporal structure functions of the cloud field are computed and analysed for the seasons. The results give a numerical representation of the effects of the general circulation and the geographical-physical conditions on cloudiness.  相似文献   
352.
A study carried out by a team of seven scientists appointed by ESA resulted in the design of a biological laboratory "Biolab" for Columbus APM. The basis for the study were four pre-Phase A studies performed by industry on the assumption that 15 racks would be available to biology and biotechnology in the APM. Due to the constraints newly imposed by the Columbus project, only five racks are now allocated. The tasks of the Biolab scientific team were: (i) to define the scientific objectives of biological research in Columbus; (ii) to review the requirements of the industrial studies; and (iii) to design a multi-purpose facility compatible with the present constraints and satisfying the requirements of the biological investigations considered in the four studies. The Biolab team was able to define a facility capable of accommodating in five racks the following biological objects: small plants (up to 40 cm), insects like drosophila, frog eggs, single cells from animals, bacteria, slime molds and protozoa, as well as human physiology, but restricted to general diagnostic needs. The Biolab facility includes instruments and devices providing the capacity of holding and/or growing the organisms as well as to perform basic experimentation and a minimum essential diagnostic inflight. Within the growth unit the growth chambers/incubators are exchangeable, permitting the use of growth chambers of different sizes. The temperature will be adjustable to the requirements of the objects under investigation, i.e. either 20 or 37 degrees C. Thus a considerable level of flexibility will permit to investigate a broad spectrum of living systems.  相似文献   
353.
One instrument of the Canadian Auroral Network for the Open Program Unified Study (CANOPUS) is a pulsed dual bistatic auroral radar system (BARS) for the mapping of ionospheric electric fields, using the STARE technique originated by R.A. Greenwald [14]. The Canadian system is presently in the specification and design phases, with the objective of being operational by mid-1984. This paper describes the geometry of the BARS system, the design considerations, and the planned data and control network.  相似文献   
354.
355.
The STructure and Atmospheric Turbulence Environment (STATE) experiment was conducted during the second week of June 1983 at Poker Flat Research Range, Alaska. The measurements focus on a study of the middle atmosphere dynamics by comparison between in-situ probe measurements and MST radar measurements. Rocket launchings were conducted at three periods which were selected by monitoring the doppler velocity spectra of the MST radar.The STATE program has included the efforts of several scientists in planning and carrying out the ground-based and rocket measurements. An overview of the program is given together with some preliminary results. The regions in intense backscatter signals detected by the MST radar are shown to correlate with large irregularities in the electron profiles measured.  相似文献   
356.
The Pioneer 11 Infrared Radiometer instrument made observations of Saturn and its rings in broadband channels centered at 20 and 45 μm and obtained whole-disk information on Titan. A planetary average effective temperature of 96.5±2.5 K implies a total emission 2.8 times the absorbed sunlight. Correlation with radio science results implies that the molar fraction of H2 is 90±3% (assuming the rest is He). Temperatures at the 1 bar level are 137 to 140 K; regions appearing cooler may be overlain by a cloud acting as a 124 K blackbody surface. A minimum temperature averaging 87 K is reached near 0.06 bars. Ring boundaries and optical depths are consistent with those at optical wavelengths. Ring temperatures are 64–86 K on the south (illuminated) side, ~54 K on the north (unilluminated) side, and at least 67 K in Saturn's shadow. There is evidence for a south to north drop in ring temperatures. Titan's 45 μm brightness temperature is 75±5 K.  相似文献   
357.
An electrical power system for a space-based radar satellite is described. When the radar is on, its transmitter needs an average DC power of 30 kW. The problem of distributing the power efficiently in pulses to many transmit/receive modules is addressed. System requirements include a high-voltage battery and transmission line, load-sharing between the solar array, and the battery during sunlit periods, and a 25-kW solar array. A scaled-down version of the power system for a proof-of-concept demonstration is described  相似文献   
358.
The early evolution of a photocatalytic system of the porphyrin type, able to efficiently collect and utilize solar energy for primary electron transfer is discussed. Experimental results concerning some spectral and photochemical properties of the porphyrins, biosynthetic precursors of chlorophyll and their complexes with polymeric templates are reviewed. Protoporphyrin IX associated with pigmented proteinoid is demonstrated to be a favourable candidate for a role of a photosensitizer of the first photosynthetic reaction centers. The origin and early evolution of the photosynthetic electron transfer chain and of the phosphorylating mechanism are discussed with emphasis on the energetic mechanisms of archaebacteria.  相似文献   
359.
We present data from the Lexan top stacks in the Heavy Ions In Space (HIIS) experiment which was flown for six years (April 1984-Jan 1990) onboard the LDEF spacecraft in 28.5 degrees orbit at about 476 km altitude. HIIS was built of passive (i.e. no timing resolution) plastic track detectors which collected particles continuously over the entire mission. In this paper we present data on low energy heavy ions (10 < or = Z, 20MeV/nuc < E < 200 MeV/nuc). These ions are far below the geomagnetic cutoff for fully ionized ions in the LDEF orbit even after taking into account the severe cutoff suppression caused by occasional large geomagnetic storms during the LDEF mission. Our preliminary results indicate an unusual elemental composition of trapped particles in the inner magnetosphere during the LDEF mission, including both trapped anomalous cosmic ray species (Ne, Ar) and other elements (such as Mg and Fe) which are not found in the anomalous component of cosmic rays. The origin of the non-anomalous species is not understood, but they may be associated with the solar energetic particle events and geomagnetic disturbances of 1989.  相似文献   
360.
The Shuttle Activation Monitor (SAM) experiment was flown on the Space Shuttle Columbia (STS-28) from 8-13 August, 1989 in a 57 degrees, 300 km orbit. One objective of the SAM experiment was to determine the relative effect of different amounts of shielding on the gamma-ray backgrounds measured with similarly configured sodium iodide (NaI) and bismuth germante (BGO) detectors. To achieve this objective twenty-four hours of data were taken with each detector in the middeck of the Shuttle on the ceiling of the airlock (a high-shielding location) as well as on the sleep station wall (a low-shielding location). For the cosmic-ray induced background the results indicate an increased overall count rate in the 0.2 to 10 MeV energy range at the more highly shielded location, while in regions of trapped radiation the low shielding configuration gives higher rates at the low energy end of the spectrum.  相似文献   
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