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51.
We consider a relationship between the difference in spectral indices of the spectra of single hadrons and all hadrons (sngl – h) and the difference in the indices of the spectra of galactic cosmic ray (GCR) protons and nuclei. It is demonstrated that at the mountain level the ratio (p – Z)/(sngl – h) is always larger than unity, if (sngl – h) > 0.1. From the experimental value sngl – h = 0.4 ± 0.05 we derive that, in the vicinity of E = 10 TeV, p – Z 0.49 ± 0.06 , i.e., p 3.09 ± 0.06.__________Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 2, 2005, pp. 83–87.Original Russian Text Copyright © 2005 by Grigorov, Tolstaya. 相似文献
52.
Pulsation and vibration process in high speed centrifugal pumps and feed lines were investigated. Linear and quadratic relations between pulsation parameters and main factors were obtained. The investigation of turbopump low frequency oscillations showed that the intensity of pulsations is proportional to the pump specific linear size. Linear mathematic models with lumped parameters fairly well demonstrate the vibration influence on low frequency flow pressure vibrations in pumps and feed lines. It is shown that, in some conditions, the pressure oscillation amplitude distribution by the vibrating feed lines length may be characterized by the presence of a node in an intermediate section. A one-dimensional mathematic model based on wave equations proved to be suitable for calculations of vibration and pulsation parameters within a wide frequency range. 相似文献
53.
In a number of flights, cosmonauts and astronauts have experienced aggravation of their health status and general condition in the initial hours and days in a weightless environment. One of the trigger mechanisms for the onset of these unfavourable conditions at the start of space flight is a redistribution of body fluids and a blood shift towards the head. To ensure controlled hypohydration as a countermeasure to the deleterious effects of 0-g and to investigate the feasibility to control adaptation, six cosmonauts were administered lasix once a day during the first 3 days of a mission. All data of the experiment (correction test, questionnaire, hematocrit) were recorded on a special form in the logbook and transmitted to the control centre for processing. Results showed that the diuretic weakened the sensation of discomfort and improved the cosmonauts' general condition. Objective indices of the correction test indicate an increased work ability of cosmonauts. After hypohydration, circulating plasma volumes in the group were reduced by 6.8 + 1.0% on average. 相似文献
54.
Tether Satellite System Collision Study 总被引:1,自引:0,他引:1
A study was performed to determine the probability of collision with resident space objects and untrackable debris for the tether component of the Tethered Satellite System (TSS) after it broke away from the Space Shuttle orbiter (mission STS-75) in February 1996. Both an analytical and a numerical approach were used in this study, and the results obtained with these two methods were found to be in good agreement. These results show that the deployed tether is expected to have been impacted by several particles 0.1mm or larger in size. The probability of collision with objects 10cm in size or larger was on the order of 10–3 per month. Since the severed tether reentered within one month after deployment, the collision hazard to other objects while in orbit was small. The analytical methods used in this study are useful for tether collision evaluations in general. 相似文献
55.
L L Stazhadze I B Goncharov I P Neumyvakin V V Bogomolov I V Vladimirov 《Acta Astronautica》1981,8(9-10):1109-1113
When discussing problems related to medical service in space flight, particular attention should be given to the specific living conditions and changes associated with space flight. In disease and injury, surgery can be provided only after conservative therapy has failed. In this context gnotobiological chambers allowing surgery in aseptic conditions seem promising. A portable set of interchangeable surgical tools should be made of light-weight alloys that can be readily sterilized. Electroanalgesia in combination with auriculoacupuncture as well as peridureal anesthesia may be used as they allow normal operations in autonomous space flight conditions. Changes in the sympatho-adrenal and kallikrein-kinin systems, as well as water-electrolyte balance, should be taken into account in developing methods and means of medical service in critical situations. Special attention should be given to the prevention and treatment of brain edema in view of weightlessness-induced cephalad fluid shifts. 相似文献
56.
V V Demidov A A Goncharov V B Osipov V I Trofimov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1995,15(3):251-255
The viewpoint of working group of Russian experts on the problem of planetary protection for future manned and unmanned Mars mission is presented. Recent data of Martian environment and on survival of terrestrial microorganisms in extreme conditions were used for detailed analysis and overview of planetary protection measures in regard to all possible flight situations including accidental landing. The special emphasis on "Mars-94" mission was done. This analysis resulted in revised formulation of spacecraft sterilization requirements and possible measures for their best implementation. New general combined approach to spacecraft sterilization was proposed. It includes penetrating radiation and heat treatment of spacecraft parts and components which is to be carried out before the final assembly of spacecraft and gaseous radiation sterilization of the whole spacecraft during the flight to Mars (or from Mars for return missions). 相似文献
57.
B. Valnicek V. Vanysek 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(12):137-141
A total of 3600 spectra of Comet Halley in the 275–710 nm were obtained on March, 8, 9, 10 and 11, 1986, from the VEGA 2 spacecraft. The emissions of OH, NH, CN, C3, CH, C2, NH2 and H2O+ are identified. From the OH intensity in the (0,0) band: 1.1 Megarayleigh at 5400 km from the nucleus, it can be inferred that the OH production rate was (1.4 ± 0.5)×1030 molecules s−1. The NH, C3, CH and NH2 bands became comparatively more intense at distances from the nucleus shorter than 3000km. At 06:40 U.T. when the instrument field of view was 6000×4500 km, two jets were observed. Spectra from the jets show significant differences with other spectra. Inside a jet NH, C3 and NH2 are comparatively more intense and the rotational distributions of OH, CN and C2 are strongly distorted. This shows that part of the observed emissions probably comes from radicals directly produced in the excited state during the initial process of photolysis of the parent molecules. 相似文献
58.
D O Klymchuk E L Kordyum T V Vorobyova D K Chapman C S Brown 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(10):2283-2288
Changes in the vacuolation in root apex cells of soybean (Glycine max L. [Merr.]) seedlings grown in microgravity were investigated. Spaceflight and ground control seedlings were grown in the absence or presence of KMnO4 (to remove ethylene) for 6 days. After landing, in order to study of cell ultrastructure and subcellular free calcium ion distribution, seedling root apices were fixed in 2.5% (w/v) glutaraldehyde in 0.1 M cacodylate buffer and 2% (w/v) glutaraldehyde, 2.5% (w/v) formaldehyde, 2% (w/v) potassium antimonate K[Sb(OH)6] in 0.1 M K2HPO4 buffer with an osmolarity (calculated theoretically) of 0.45 and 1.26 osmol. The concentrations of ethylene in all spaceflight canisters were significantly higher than in the ground control canisters. Seedling growth was reduced in the spaceflight-exposed plants. Additionally, the spaceflight-exposed plants exhibited progressive vacuolation in the root apex cells, particularly in the columella cells, to a greater degree than the ground controls. Plasmolysis was observed in columella cells of spaceflight roots fixed in solutions with relatively high osmolarity (1.26 osmol). The appearance of plasmolysis permitted the evaluation of the water status of cells. The water potential of the spaceflight cells was higher than the surrounding fixative solution. A decrease in osmotic potential and/or an increase in turgor potential may have induced increases in cell water potential. However, the plasmolysed (i.e. non-turgid) cells implied that increases in water potential were accompanied with a decrease in osmotic potential. In such cells changes in vacuolation may have been involved to maintain turgor pressure or may have been a result of intensification of other vacuolar functions like digestion and storage. 相似文献
59.
Nussinov MD Burdyuzha VV Gleizer SI 《Journal of the British Interplanetary Society》1992,45(6):251-255
An analysis of the experimental data available and of the present theoretical concepts shows that even the initial physicochemical chemical precellular stages of biological evolution are impossible in the interstellar medium, while biomonomers possibly formed on asteroids and comets might have participated after transportation to the Earth in the final stages of the origin of the first precellular biological structures and then in the first living cells. 相似文献
60.
Nussinov MD Lysenko SV Kozlovskii MYu Pogodin YuS 《Journal of the British Interplanetary Society》1992,45(1):13-14
The use of charge-coupled devices is suggested as a means for detecting growth of micro-organism colonies. The accuracy of the method is determined by channel width and the sensitivity by the signal/noise ratio. The method was tested on a dense nutrient medium, which is to be considered more suitable to micro-organisms of the dry Martian soil than the water solution of nutrients employed in the Viking's strategy. 相似文献