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41.
C. Unglaub Ch. Jacobi G. Schmidtke B. Nikutowski R. Brunner 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Primary photoionisation of major ionospheric constituents is calculated from satellite-borne solar EUV measurements. Number densities of the background atmosphere are taken from the NRLMSISE-00 climatology. From the calculated ionisation rates, a proxy termed EUV-TEC, which is based on the global total ionisation is calculated, and describes the ionospheric response to solar EUV and its variability. The proxy is compared against the global mean ionospheric total electron content (TEC) derived from GPS data. Results show that the EUV-TEC proxy provides a better overall representation of global TEC than conventional solar indices like F10.7 do. The EUV-TEC proxy may be used for scientific research, and to describe the ionospheric effects on radio communication and navigation systems. 相似文献
42.
Ch.-H. Chun 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(5):183-186
During a 6-minutes free flight of a sounding rocket an experiment on the thermal Marangoni convection in a right circular cylindric floating zone was carried out to verify the thermal Marangoni convection by flow visualisation for the first time at 10?4 g. From the motion picture analysis the velocity distributions are obtained. The interdependence between the two velocity maxima and the S-shaped temperature distribution on the free surface is discussed. The influence of the heat transfer caused by the flow of the surrounding air induced by the thermal Marangoni convection itself is considered briefly. 相似文献
43.
Global monitoring of tropospheric water vapor with GPS radio occultation aboard CHAMP 总被引:1,自引:0,他引:1
S. Heise J. Wickert G. Beyerle T. Schmidt Ch. Reigber 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,37(12):2222-II
The global positioning system radio occultation (GPS RO) technique provides a powerful tool for atmospheric sounding which requires no calibration, is not affected by clouds, aerosols or precipitation, and provides an almost uniform global coverage. The paper deals with application of GPS RO measurements from CHAllenging Minisatellite Payload (CHAMP) for the retrieval of tropospheric water vapor profiles. CHAMP RO data are available since 2001 with up to 200 high resolution atmospheric profiles per day. We introduce a new direct method for water vapor retrieval from GPS RO data. Additionally, a 1Dvar algorithm is used for this purpose. The so derived CHAMP water vapor profiles are validated with radiosonde data on a global scale. Here, both methods come to statistically comparable results revealing a negative bias of less than 0.1 g/kg and a standard deviation of less than 1 g/kg specific humidity in the mid troposphere. Potentials of CHAMP RO retrievals for monitoring the mean tropospheric water vapor distribution on a global scale are presented. 相似文献
44.
The "C.E.B.A.S. MINI-MODULE": a self-sustaining closed aquatic ecosystem for spaceflight experimentation. 总被引:1,自引:0,他引:1
V Blum M Andriske Ch Ludwig U Paassen D Voeste 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):201-210
The C.E.B.A.S. MINI-MODULE is the miniaturized space flight version of the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.). It fits into a large middeck locker tray and is scheduled to be flown in the STS 85 and in the NEUROLAB missions. Its volume is about 9 liters and it consists of two animal tanks, a plant cultivator, and a bacteria filter in a monolithic design. An external sensor unit is connected to a data acquisition/control unit. The system integrates its own biological life support. The CO2 exhaled by the consumers (fishes, snails, microorganisms) is assimilated by water plants (Ceratophyllum demersum) which provide them with oxygen. The products of biomass degradation and excretion (mainly ammonia ions) are converted by bacteria into nitrite and nitrate. The latter is taken up by the plants as a nitrogen source together with other ions like phosphate. The plants convert light energy into chemical energy and their illumination is regulated via the oxygen concentration in the water by the control unit. In ground laboratory tests the system exhibited biological stability up to three month. The buffer capacity of the biological filter system is high enough to eliminate the degradation products of about one half of the dead animal biomass as shown in a "crash test". A test series using the laboratory model of the flight hardware demonstrated the biological stability and technical reliability with mission-identical loading and test duration. A comprehensive biological research program is established for the C.E.B.A.S. MINI-MODULE in which five German and three U.S.-American universities as well as the Russian Academy of Sciences are involved. 相似文献
45.
46.
Ch. Jacobi K. Fröhlich Y. Portnyagin E. Merzlyakov T. Solovjova N. Makarov D. Rees A. Fahrutdinova V. Guryanov D. Fedorov D. Korotyshkin J. Forbes A. Pogoreltsev D. Kürschner 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
During recent years, special attention has been paid to understanding the background circulation of the middle atmosphere. Particularly in the mesosphere/lower thermosphere (MLT) region, this has involved including data from a range of new radar measurements. It has also involved the comparison of existing empirical middle atmosphere wind models, such as CIRA-86 and HWM-93 to the new data. This has led to the construction of empirical models of MLT winds such as the Global Empirical Wind Model (GEWM). Further investigations are aimed at the construction of new empirical and semi-empirical wind models of the entire middle atmosphere including these new experimental results. The results of a new wind climatology (0–100 km) are presented here, based upon the GEWM, a reanalysis of stratospheric data, and a numerical model which is used to fill the gap between data from the stratospheric and MLT regions. 相似文献
47.
Mass exchange in an experimental new-generation life support system model based on biological regeneration of environment. 总被引:3,自引:0,他引:3
A A Tikhomirov S A Ushakova N S Manukovsky G M Lisovsky Yu A Kudenko V S Kovalev V G Gubanov Yu V Barkhatov I V Gribovskaya I G Zolotukhin J B Gros Ch Lasseur 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(7):1711-1720
An experimental model of a biological life support system was used to evaluate qualitative and quantitative parameters of the internal mass exchange. The photosynthesizing unit included the higher plant component (wheat and radish), and the heterotrophic unit consisted of a soil-like substrate, California worms, mushrooms and microbial microflora. The gas mass exchange involved evolution of oxygen by the photosynthesizing component and its uptake by the heterotroph component along with the formation and maintaining of the SLS structure, growth of mushrooms and California worms, human respiration, and some other processes. Human presence in the system in the form of "virtual human" that at regular intervals took part in the respirative gas exchange during the experiment. Experimental data demonstrated good oxygen/carbon dioxide balance, and the closure of the cycles of these gases was almost complete. The water cycle was nearly 100% closed. The main components in the water mass exchange were transpiration water and the watering solution with mineral elements. Human consumption of the edible plant biomass (grains and roots) was simulated by processing these products by a unique physicochemical method of oxidizing them to inorganic mineral compounds, which were then returned into the system and fully assimilated by the plants. The oxidation was achieved by "wet combustion" of organic biomass, using hydrogen peroxide following a special procedure, which does not require high temperature and pressure. Hydrogen peroxide is produced from the water inside the system. The closure of the cycle was estimated for individual elements and compounds. Stoichiometric proportions are given for the main components included in the experimental model of the system. Approaches to the mathematical modeling of the cycling processes are discussed, using the data of the experimental model. Nitrogen, as a representative of biogenic elements, shows an almost 100% closure of the cycle inside the system. The proposed experimental model of a biological system is discussed as a candidate for potential application in the investigations aimed at creating ecosystems with largely closed cycles of the internal mass exchange. The formation and maintenance of sustainable cycling of vitally important chemical elements and compounds in biological life support systems (BLSS) is an extremely pressing problem. To attain the stable functioning of biological life support systems (BLSS) and to maintain a high degree of closure of material cycles in than, it is essential to understand the character of mass exchange processes and stoichiometnc proportions of the initial and synthesized components of the system. 相似文献
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49.
A.A. Galeev I.Ch. Chabibrachmanov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(3):71-75
The ionization of the gas ejections from the Io satellite into the Jovian magnetosphere by the corotating magnetospheric plasma flow is considered. It is shown that the plasma flow velocity at the Io orbit exceeds the critical velocity at which the anomalous electron ionization of the heavy gas components takes place due to collisionless energy transfer from ionized gas atoms to plasma electrons. The energy, number density and spatial distribution of suprathermal electrons is calculated using the quasilinear theory of newly ionized atoms instability in a moving plasma. Saturation of the plasma density build up in a plasma is considered in terms of the instability quenching by Coulomb collisions. 相似文献
50.
A review is made on the design philosophy of groundbased multichannel spectrometers for measurements of solar irradiation reflected from various natural formations within the visible and near infrared range of the electromagnetic spectrum. Important specifics of the new generation ground-based spectrometers are the improved functional possibilities for the scientific experiments, management and for the specialized data processing. The instruments enable the performance both of automated mode of operation and within the payload of complex measurement equipment. The incorporation of proper computer techniques accounts for the increased intelligence and adaptivity which provides for the precise resolution necessary for the scientific methodology and applicable tasks. 相似文献