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991.
O.H.库德尔雅绍夫 《航空精密制造技术》1999,35(6)
介绍了俄罗斯大型运载火箭壳体结构的材料。装配和焊接概况.对我国同类型航天火箭的制造有参考和借鉴意义. 相似文献
992.
A. Dmitriev S. Kuznetsov P. Shavrin V. Lyagushin O. Nechaev M. Panasyuk E. Tolstaya M. Nikiforova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,21(12):1797-1800
A set of instruments for measuring energetic particle fluxes, containing two neutron detectors under different plexiglas shielding thicknesses, a scintillation detector, measuring energy release >0. I MeV and 0.5 MeV and a Geiger counter were launched onboard OS ‘MIR’. The latitude dependencies of the cosmic ray measurements were obtained and studied. The distributions of primary particle fluxes (protons and electrons) as well as secondary particle fluxes (bremsstrahlung gamma-rays and neutrons) produced in interactions of radiation belt particles with the station materials were obtained. The electron belt, generated during the storm of March 24 1991, is studied. 相似文献
993.
O.?V.?SapunovaEmail author N.?L.?Borodkova V.?G.?Eselevich G.?N.?Zastenker Yu.?I.?Yermolaev 《Cosmic Research》2017,55(6):396-402
The paper is concerned with studying the thickness of fronts of 38 interplanetary shocks detected by the BMSW instrument, which is a part of the scientific payload of the SPEKTR-R spacecraft, which was launched into a highly elliptical orbit in 2011. The main parameters of the interplanetary shocks have been calculated as follows: the ratio of thermal pressure to magnetic pressure before the front β, the angle between the shock front normal and the undisturbed magnetic field θBn, the ratio of the shock propagation velocity to the magnetosonic velocity in the undisturbed region Mms, and the shock front velocity relative to the Earth. It has been shown that the front thickness determined from the plasma parameters approximately matches the front thickness obtained from the magnetic field measurements and lies between 0.5 and 5 proton inertial lengths. In some events, the oscillations have been observed (upstream and downstream of the shock) in plasma parameters and in the magnetic field data. The length has been found to be between 0.5 and 6 proton inertial lengths for the preceding oscillations and between 0.5 and 10 proton inertial lengths for the following oscillations. The average value of the proton inertial length is 62 km. 相似文献
994.
Results of laboratory measurements of the dielectric characteristics of lunar soil samples returned to the Earth by the Luna and Apollo missions have been analyzed. The feasibility of determining the density of the upper cover of the Moon from the permittivity, which is restored as a result of solving the inverse problem of radiolocation, has been discussed. A formula has been proposed for approximating the frequency dependence of the loss tangent for the regolith and bedrock. Relationships have been deduced for estimating the percentage of metal oxides in the lunar soil. 相似文献
995.
A I Grigoriev L B Buravkova V A Loginov O L Vinogradova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,20(7):1397-1399
The problems and approaches to organisation of the education process in the field of aerospace and environmental medicine for medical students are discussed. Original education developed on the basis of Russian experience in space biology and physiology, environmental medicine, aerospace medicine and medical support during spaceflight. The main goals of these programs are to acquaint students with: interaction of living organisms with natural and artificial surroundings, including space flight conditions; the physiological reactions on extreme environmental factors; basic mechanisms of human adaptation to space flight and particularly to microgravity; the current research in space medicine and new telecommunication technologies. All programs are formed in accordance with contemporary progress in life sciences and revealed a result of the interdisciplinary approach to education process. 相似文献
996.
Energetic (0.1-16 keV/e) ion data from a plasma composition experiment on the ISEE-1 spacecraft show that Earth's plasma sheet (inside of 23 RE) always has a large population of H+ and He++ ions, the two principal ionic components of the solar wind. This population is the largest, in terms of both number density and spatial thickness, during extended periods of northward interplanetary magnetic field (IMF) and is then also the most "solar wind-like" in the sense that the He++/H+ density ratio is at its peak (about 3% on average in 1978 and 79) and the H+ and He++ have mean (thermal) energies that are in the ratio of about 1:4 and barely exceed the typical bulk flow energy in the solar wind. During geomagnetically active times, associated with southward turnings of the IMF, the H+ and He++ are heated in the central plasma sheet, and reduced in density. Even when the IMF is southward, these ions can be found with lower solar wind-like energies closer to the tail lobes, at least during plasma sheet thinning in the early phase of substorms, when they are often seen to flow tailward, approximately along the magnetic field, at a slow to moderate speed (of order 100 km s-1 or less). These tailward flows, combined with the large density and generally solar wind-like energies of plasma sheet H+ and He++ ions during times of northward IMF, are interpreted to mean that the solar wind enters along the tail flanks, in a region between the lobes and the central plasma sheet, propelled inward by ExB drift associated with the electric fringe field of the low latitude magnetopause boundary layer (LLBL). In order to complete this scenario, it is argued that the rapid (of order 1000 km s-1) earthward ion flows (mostly H+ ions), also along the magnetic field, that are more typically the precursors of plasma sheet "recovery" during substorm expansion, are not proof of solar wind entry in the distant tail, but may instead be a time-of-flight effect associated with plasma sheet redistribution in a dipolarizing magnetic field. 相似文献
997.
Morphology and physics of short-period magnetic pulsations 总被引:5,自引:0,他引:5
This review is devoted to the main problems of experimental and theoretical investigations of geoelectromagnetic waves in the frequency range from 0.1 to 5 Hz. These waves constitute the short-period subclass of so-called geomagnetic pulsations. The short-period pulsations are represented by Pc1, Pc2, Pi1, Ipdp types and some subclassifications. The understanding of the pulsation mechanisms provides an insight into the structure and dynamics of the Earth's magnetosphere. We focus our attention on Pc1 pearl pulsations and on the classical (evening) Ipdp, for which basic physical concepts have been established. Other types and varieties are outlined also, but in less detail. In these cases, the physical mechanism is not always clear (as, for example, in the case of morning Ipdp), and/or the morphology is still to be determined carefully (Pc2 and discrete signals in polar cusps as typical examples).Short-period pulsations are a spontaneous, sporadic phenomenon which undergo a certain evolution in the course of a magnetic storm. We consider the storm-time variation as a natural background, and we use this background to collect the information about the pulsations in an orderly manner. At the same time, together with the transient storm-time variation of pulsation activity, quasi-periodic variations take place, which are connected with the Earth's and Sun's rotation, Earth's orbital motion and solar cycle activity. The study of these regular variations allows us to have a new approach to the mechanisms of excitation and propagation of short-period geomagnetic pulsations. 相似文献
998.
J. Kleczek H. Nussbaumer K. A. van der Hucht J. P. de Greve G. Ooms R. J. Rutten H. van der Laan F. W. Jäger G. C. M. Reijnen w. Bijleveld J. Kistemaker C. de Jager E. R. Mustel Y. Ne'eman E. R. Priest H. Stiller W. Seifert O. Namba M. Kuperus Roel Hoekstra F. L. H. M. Stumpers S. Frank J. T. F. Zimmerman C. de Loore R. Gendrin J. Schrijver P. S. Mulder K. A. Pounds R. S. Young L. Houziaux O. Engvold B. J. Bok W. de Graaff 《Space Science Reviews》1983,36(4):415-432
999.
O. Ooms Hans Van Der Woerd Henny J. G. L. M. Lamers Josip Kleczek J. Kovalevsky R. Gathier T. Jarzebowski J. P. Swings K. A. van der Hucht O. Namba R. Mewe D. Lynden-Bell Jan Kuijpers M. van der Klis D. de Hoop H. Wittenberg W. Iwanowska P. S. Thé J. Schrijver S. R. Pottasch 《Space Science Reviews》1984,38(3-4):385-387
1000.
K. O. Mason 《Space Science Reviews》1985,40(1-2):99-115
EXOSAT results on cataclysmic variables are reviewed. The long continuous X-ray observations afforded by this observatory, coupled with the sensitivity of its instruments to medium energy and very low energy X-rays, have enabled the rotational and orbital X-ray light curves of these stars to be measured in unprecedented detail. Examples are given of data on synchronously and asynchronously rotating magnetic systems, and on disc accreting stars. The impact of the new observations on our understanding of cataclysmic variables is discussed. 相似文献