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411.
V. A. Fedorov 《Cosmic Research》2006,44(1):9-18
Mechanisms of generation and dynamics of HF and LF emissions related to an electron beam injection from a spacecraft into the ionosphere are studied. The choice of the source and region of emission is substantiated. The plasma current neutralizing the spacecraft charge and the region of spatial charge in the vicinity of the spacecraft are chosen. Mechanisms of the generation of HF and LF emissions are proposed and their characteristics are determined. For the considered ranges of emission, the explanation of the facts related to the difficulties in interpretation of the amplitude value observed experimentally and the behavior of its envelope are presented. It is shown that the results obtained in this work agree well with the data of the conducted experiments. 相似文献
412.
B.V. Somov T. Kosugi H.S. Hudson T. Sakao S. Masuda 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,32(12):2439-2450
The basic ideas to model the large solar flares are reviewed and illustrated. Some fundamental properties of potential and non-potential fields in the solar atmosphere are recalled. In particular, we consider a classification of the non-potential fields or, more exactly, related electric currents, including reconnecting current layers. The so-called ‘rainbow reconnection’ model is presented with its properties and predictions. This model allows us to understand main features of large flares in terms of reconnection. We assume that in the two-ribbon flares, like the Bastille-day flare, the magnetic separatrices are involved in a large-scale shear photospheric flow in the presence of reconnecting current layers generated by a converging flow. 相似文献
413.
Ts P Dachev E G Stassinopoulous B T Tomov Pl G Dimitrov Yu N Matviichuk V A Shurshakov V M Petrov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,32(1):67-71
The LIULIN-3M instrument is a further development of the LIULIN dosimeter-radiometer, used on the MIR spacestation during the 1988-1994 time period. The LIULIN-3M is designed for continuous monitoring of the radiation environment during the BION-12 satellite flight in 1999. A semiconductor detector with 1 mm thickness and cm2 area is contained in the instrument. Pulse high analysis technique is used to determine the energy losses in the detector. The final data from the instrument are the flux and the dose rate for the exposure time and 256 channels of absorbed dose spectra based on the assumption that the particle flux is normal to the detector. The LIULIN-3M instrument was calibrated by proton fluxes with different energies at the Indiana University Cyclotron Facility in June 1997 and had been used for radiation measurements during commercial aircraft flights. The calibration procedure and some flight results are presented in this paper. 相似文献
414.
G. V. Kasatkin 《Cosmic Research》2007,45(2):110-125
Attractive forces inside a thin nonuniform meteor ring are found and their features are revealed. 相似文献
415.
E.B. Romanova O.M. Pirog N.M. Polekh A.V. Tashchilin G.A. Zherebtsov J.K. Shi X. Wang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(4):569-578
The results of modeling of ionospheric disturbances observed in the East Asian region during moderate storms are presented. The numerical model for ionosphere–plasmasphere coupling developed at the ISTP SB RAS is used to interpret the data of observations at ionospheric stations located in the longitudinal sector of 90–130°E at latitudes from auroral zone to equator. There is obtained a reasonable agreement between measurements and modeling results for winter and equinox. In the summer ionosphere, at the background of high ionization by the solar EUV radiation in the quiet geomagnetic period the meridional thermospheric wind strongly impacts the electron concentration in the middle and auroral ionosphere. The consistent calculations of the thermospheric wind permit to obtain the model results which are closer to summer observations. The actual information about the space-time variations of thermosphere and magnetosphere parameters should be taken into account during storms. 相似文献
416.
West W.C. Whitacre J.F. Brandon E.J. Ratnakumar B.V. 《Aerospace and Electronic Systems Magazine, IEEE》2001,16(8):31-33
Recent successes in the effort to miniaturize spacecraft components using MEMS technology, integrated passive components, and low power electronics have driven the need for very low power, low profile, low mass micro-power sources for micro/nanospacecraft applications. Recent work at JPL has focused upon developing thin film/micro-batteries compatible with temperature sensitive substrates. A process to prepare crystalline LiCoO2 films with RF sputtering and moderate (<700°C) annealing temperature has been developed. Thin film batteries with cathode films prepared with this process have specific capacities approaching the practical limit for LiCoO2, with acceptable rate capabilities and discharge voltage profiles. Solid-state micro-scale batteries have also been fabricated with feature sizes on the order of 50 microns 相似文献
417.
R Facius K Scherer G Reitz H Bucker L V Nevzgodina E N Maximova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(10):93-103
The potentially specific importance of the heavy ions of the galactic cosmic radiation for radiation protection in manned spaceflight continues to stimulate in situ, i.e., spaceflight experiments to investigate their radiobiological properties. Chromosome aberrations as an expression of a direct assault on the genome are of particular interest in view of cancerogenesis being the primary radiation risk for man in space. In such investigations the establishment of the geometrical correlation between heavy ions' trajectories and the location of radiation sensitive biological substructures is an essential task. The overall qualitative and quantitative precision achieved for the identification of particle trajectories in the order of approximately 10 micrometers as well as the contributing sources of uncertainties are discussed. We describe how this was achieved for seeds of Lactuca sativa as biological test organisms, whose location and orientation had to be derived from contact photographies displaying their outlines and those of the holder plates only. The incidence of chromosome aberrations in cells exposed during the COSMOS 1887 (Biosatellite 8) and the COSMOS 2044 (Biosatellite 9) mission was determined for seeds hit by cosmic heavy ions. In those seeds the incidence of both single and multiple chromosome aberrations was enhanced. The results of the Biosatellite 9 experiment, however, are confounded by spaceflight effects unrelated to the passage of heavy ions. 相似文献
418.
I.V. Chashei 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,20(12):2299-2302
Small scale turbulence in the solar corona and the solar wind is considered. The estimates of dissipation scale in the inner heliosphere are obtained in the assumption that the initial source of turbulence is located near the chromosphere-corona transition layer. Theoretical results are compared with radiooccultation data. 相似文献
419.
V. Formisano V.I. Moroz H. Hirsch P. Orleanski G. Michel J. Lopez-Moreno E. Amata G. Bellucci G. Piccioni G. Chionchio A. Carusi A. Coradini P. Cerroni M.T. Capria F. Capaccioni A. Adriani M. Vitterbini F. Angrilli G. Bianchini B. Saggin S. Fonti E. Bussoletti D. Mancini L. Colangeli A. Grigoriev B. Moshkin V. Gnedykh I.A. Matsygorin D. Patsaev Yu.V. Nikolsky D.V. Titov L.V. Zasova I. Khatuntsev A. Kiselev G. Arnold H. Driesher M.I. Blecka R. Rodrigo J. Rodriguez-Gomez 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,17(12):61-64
Thin films containing a mixture of aliphatic (glycine) and aromatic (tryptophan or tyrosine) amino acids were exposed to a vacuum ultraviolet radiation (VUV) with wavelenghts 100–200 nm. Dipeptides (glycyl-tryptophan and glycyl-tyrosine) were synthesized in these conditions. We compared the actions of VUV and γ-radiation. Polymerization is an essential step in prebiological evolution and we have shown that this stage probably occured over an early Solar system history. 相似文献
420.
K. Kudela V. N. Lutsenko D. G. Sibeck M. Slivka T. V. Gretchko E. T. Sarris 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2002,30(12):2849-2854
Time period from October 1996 until January 1998 was checked on high energy resolution DOK2 energetic particle instrument measurements on Interball-1 and Interball-2 for the ion (> 20 keV) dispersive events (EDIS) with the exclusion of Interball-1 orbit parts in the tail. A variety of energy dispersive events, both in ion and electron spectra with different duration is found in the auroral regions, in the outer magnetosphere and near the cusp. While EDIS were observed in all sectors of MLT, the best conditions for their observation were in the afternoon local time. The characteristics of dispersive events observed by DOK2 are consistent with their explanation by the gradient-curvature drift of particles from the injection point(s) in the night local time sector given in Lutsenko at al., 2000a, b. 相似文献