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681.
J.J. Berthelier A. Berthelier Yu.I. Galperin V.A. Gladyshev N.I. Massevitch F. Lefeuvre O.A. Molchanov M. Mogilevsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(7):49-52
In the Soviet-French Arcad-3 project, 3 experiments TBF-ONCH, TRAC and ISOPROBE are carried out on board the Aureol-3 satellite to measure the AC and DC electric and magnetic fields and waves. Several modes of telemetry, real time and memory regimes are available for data transmission. TBF-ONCH is devoted to the measurement of 3 components of the DC electric field, 2 electric and 3 magnetic components of the waves. In one mode of the real time telemetry these 5 components are transmitted simultaneously in the frequency range 10 Hz-1.5 kHz in order to be able to determine the wave normal directions of natural emissions and to localize their sources. In the second mode, morphological studies of saucers, chorus, hiss and triggered emissions can be undertaken using the wide band transmission (70 Hz-16 kHz) of any one of these 5 components with the possibility of periodically changing the transmitted component every 4 seconds or keeping the same one during all the pass. TRAC makes use of the on board 3 axis flux gate magnetometer to perform a fine measurement of the magnetic effects of the currents flowing in the vicinity of the spacecraft either in the ionosphere or along the magnetic field lines, with a resolution of ~ 12 nT and in the frequency range from DC to ~ 20 Hz. One component of the HF electric field (0.1–10 Mhz) is measured by ISOPROBE (see companion paper). Examples of inflight measurements from the above instruments and their presentation on microfiches are shown. Some new phenomena are emphasized and briefly discussed. 相似文献
682.
683.
O. Wolczek 《Acta Astronautica》1983,10(11):739-742
In spite of numerous observations and intense theoretical work already accomplished, many important questions concerning comets remain unsolved. The origin of comets is far from being elucidated. The nature of comets, of their nuclei seems to be reasonably described by the model of Whipple, yet their very structure and constitution remain hypothetical. The complex internal dynamics of active comets awaits a detailed explanation. One of the outstanding problems pertains to the very nature of the residual material remaining after the outgasing of the cometary nucleus. The problem is connected with the presence of organic matter, of their constituents as well as aggregates important to the development of life and to the hypothetical influence of such ingredients on the evolution of its forms already existing on some celestial bodies.It is obvious that irrespective to the recently devised methods and instruments new developments are needed. The paper attempts to show some novel ways of exploration of comets by the use of astronautical means. Recommendations for the realization of such future cometary missions are presented. 相似文献
684.
685.
O Messerschmidt 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1989,9(10):197-201
Injuries, caused by both whole-body irradiation and wounds or burns, have been relatively little studied. Possibly because many investigators think that these injuries are just modified radiation-induced diseases for which the same treatment principles are valid. Other authors had the impression that, for instance, the radiation burn trauma is a new kind of disease which differs significantly from either radiation syndrome alone or from burn disease. There are many experimental data on animals which suggest that the pathology of combined injuries differs significantly from that of radiation-induced disease or of thermal or mechanical traumas. Wounds or burns which, in general, do not cause septicaemia could become entrance ports for bacteria when animals are exposed to whole-body irradiation. Thrombocytopenia is the reason for hemorrhages in wounds. The susceptibility to shock is increased considerably in combined injuries and the formation of callus in the bone fractures is significantly delayed. The healing of wounds and burns in the initial phase of the radiation syndrome does not always differ from healing in the non-irradiated organism. However, a few days or weeks later very serious wound infections and hemorrhages can occur. The additional injuries almost always worsen the development and prognosis of radiation-induced disease. The recommended treatment for combined injuries will differ in many respects from the treatment of wounds and burns or the radiation syndrome. 相似文献
686.
H Bozouklian V Sanchez M Clifton O Marsal A Esterle 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1989,9(11):105-109
The use of electrokinetic phenomena should prove to be a promising bioseparation technique especially as an application of bioprocessing under microgravity. Therefore, a bioseparation Research and Development programme involving several research teams has been under way for three years in France. Based upon the results of this fundamental research, a programme is now proposed for the development of an automated process chain making it possible to obtain biological macromolecules of high purity under microgravity. This Space Bio Separation programme received the Eureka label at the 6th Ministerial Eureka conference. The project will last six years. It will involve the cooperation of several scientific and industrial partners in France, in Spain and in Belgium. The programme includes the development and validation of three different bioseparation facilities for space. 相似文献
687.
T. A. Parnell T. H. Burnett S. Dake J. H. Derrickson W. F. Fountain M. Fuki J. C. Gregory T. Hayashi R. Holynski J. Iwai W. V. Jones A. Jurak J. J. Lord O. Miyamura H. Oda T. Ogata F. E. Roberts S. Strausz T. Tabuki Y. Takahashi T. Tominaga J. W. Watts J. P. Wefel B. Wilczynska H. Wilczynski R. J. Wilkes W. Wolter B. Wosiek 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1989,9(12):45-54
Direct measurements on cosmic ray protons through iron above about 1 TeV/amu have been performed in a series of balloon-borne experiments with emulsion chambers. The measured energy spectra of protons and helium are power laws with exponents of 2.77 ± 0.09 and 2.72 ± 0.11 in the energy range 5 to 500 TeV and 2 to 50 TeV/amu, respectively. The proton spectrum shows no evidence of the steepening near 2 TeV which was reported by other experiments. Helium has a slightly higher intensity compared to extrapolations from lower energy measurements. The heavier elements, carbon to sulfur, show a small tendency for intensity enhancement in the relative abundance above 10 TeV/amu. 相似文献
688.
The mapping between function spaces that is implied by the representation of a real ?bandpass? function by a complex ?low-pass? function is explicitly emphasized. The discussion is extended to the representation of random processes where the mapping is between spaces of random processes. 相似文献
689.
P. Nenovski Y. Semkova R. Koleva S. Chapkunov N. Kanchev N. Tabov A. Kanchev O. Vaisberg V. Smirnov G. Zastenker A. Leibov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(7):27-30
An original instrument for ion energy distribution measurement in ionospheric plasma above the F-layer was designed and launched on board the ‘INTERCOSMOS-BULGARIA-1300’ satellite. The instrument performs differential energy analysis of ion species within the two energy ranges of 1 – 27 eV/q and 0.2–8keV/q. 相似文献
690.
E V Vashenyuk L I Miroshnichenko M O Sorokin J Perez-Peraza A Gallegos 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(10):711-716
Some of the Ground Level Enhancements of Solar Cosmic Rays (SCR) recorded by neutron monitors during solar cycle 22 are analyzed. The events appeared in series, and their occurrence rate in 1989-1991 was a factor of 4 larger than the average value (approximately 1/yr) for the total observation interval (since 1942). The events of Sept. 29 and Oct. 24, 1989 proved to be the more intensive. The analyzed events show no peculiarities as to the distribution of the T1/2 parameter, whereas the shape of the profile of some events is notable for a two peak structure. The latter implies the possibility of a two component SCR ejection from two different sources in the solar atmosphere. For the event of Sep. 29 we have estimated the ejection rigidity spectrum of protons to be Dsolar (R) = (1-2) 10(32)R(-2.9) Gv-1 at R > or = 1 Gv. As to its proton flux, this event proved to be by 1-2 orders less intensive than the well known event of Feb. 23 1956. 相似文献