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991.
G. K. Garipov P. A. Klimov V. S. Morozenko M. I. Panasyuk B. A. Khrenov 《Cosmic Research》2011,49(5):391-398
Using a detector of near ultra-violet (UV) emission (wavelength range 300–400 nm) [1] onboard the Universitetsky-Tatiana satellite with an orbit height of 950 km and inclination of 81° we have detected and studied short UV flashes [2–5]. In this
paper the observed UV flashes are classified according to the type of their time profiles, and the times of emission intensity
rise and decay are investigated in every flash. Using the data on time profiles it turned out to be possible to estimate the
flash energy in the atmosphere even in case of saturation of a signal measuring channel at the maximum of emission. The energy
spectrum of observed flashes is estimated. Time and energy characteristics of the flashes are important for choosing a model
of development of electric discharges in the upper atmosphere that are responsible for observed emission. 相似文献
992.
993.
A technique for evaluating and predicting flexural stiffness of an aircraft wing in the process of operation based on measuring
the first tone of flexural wing vibrations in flight is proposed. 相似文献
994.
In this paper, it is shown that the conventional design calculation of turbines with a zero radial clearance results in no large errors of the flow parameter determination and an additional decrease of an angle of flow outlet from the turbine rotor blade to compensate the real clearance influence brings the flow parameters closer to the design ones, but fails to provide any significant increase of turbine efficiency. 相似文献
995.
Topological model of the solar event including a flare and coronal mass ejection on October 19, 2001
Based on the analysis of a strong solar flare X1.6/2B on October 19, 2001 in the active region 9661, accompanied by a coronal mass ejection (CME) of the halo type, a topological model of development of this solar event is suggested. The model considers a unified process of development of CME and a chromosphere flare. According to the model, this process has a common source of energy supply: the turbulent current layer lying between the arcade of flare loops and the surface of CME going away. The structures on the ends of flare bands (SEFB) represent in this model chromosphere feet of the system of large-scale coronal magnetic arches at the initial stage of the dynamic processes whose evolution results in CME. Peripheral structures (PS) of the flare (elongated double bright emission strips beyond the limits of the active region) are interpreted as chromosphere bases of magnetic field lines that form an external shell (braid) of the CME at the late stage of the flare. 相似文献
996.
G. A. Zherebtsov V. A. Kovalenko S. I. Molodykh O. A. Rubtsova L. A. Vasil’eva 《Cosmic Research》2008,46(4):358-366
We present the mechanism and the concept of a model of the solar activity impact on thermobaric and climatic characteristics of the troposphere. Both are based on the idea of parametric action. The results of analysis are presented concerning specific features and regularities of changes in temperature regime of the troposphere in the period of variable helio-and geophysical activity, as well as long-term variations of temperature and heat content of the troposphere. The influence of changes in circulation in the atmosphere and ocean on processes in the system atmosphere-ocean-cryosphere is considered: thermohaline circulation of the oceans and energy exchange between the atmosphere and ocean. The revealed regularities find their complete explanation within the context of a model and mechanism of solar activity impact on climatic characteristics of the troposphere that were suggested previously by the authors. 相似文献
997.
T. K. Breus R. M. Baevskii I. I. Funtova G. A. Nikulina E. V. Alexeev A. G. Chernikova 《Cosmic Research》2008,46(4):367-372
Investigations of the effect of geomagnetic activity factors on the cardiac rhythm regulation and arterial pressure of cosmonauts during the expeditions onboard the Soyuz spacecraft, and the MIR and ISS orbital space stations was carried out for various durations of flight in weightlessness and, under control. Groups of cosmonauts were inspected under flight conditions outside the geomagnetic disturbances and in ground preflight conditions, during disturbances without them. The presence of specific effect of geomagnetic disturbances on the system of vegetative regulation of blood circulation of cosmonauts during the flight was demonstrated for the first time. The response of cosmonauts’ cardiac rhythm on the magnetic storm is definitely revealed; however, it depends on the initial functional background and, in particular, on the state of mechanisms of vegetative regulation (the duration of flight and adaptation to it). 相似文献
998.
S. I. Kozlov N. V. Smirnova T. V. Loseva A. N. Lyakhov I. B. Kosarev 《Cosmic Research》2008,46(6):489-498
A theoretical interpretation is given to the experimental data on the luminescence in the visible spectral region of the disturbed upper atmosphere in the conditions of injection of a high-velocity aluminum plasma jet (the “Fluxus” experiment). Mathematical models of optical effects are presented. It is demonstrated that the results of the calculations and the experimental data agree satisfactorily. The principal physical and chemical processes responsible for the observed luminescence are determined. 相似文献
999.
A. V. Bobylev A. A. Dyad’kin V. I. Kobzev V. M. Poedinok A. G. Reshetin S. N. Suprunenko V. A. Jaroshevskii 《Cosmic Research》2008,46(1):74-89
We consider the problems of control of the angular and trajectory motion of the Kliper re-entry vehicle. This spacecraft with a moderate hypersonic lift-to-drag ratio is designed according to the load-carrying frame scheme. Gas-dynamic engines, a split balancing flap, and an air brake are used as mounting devices of control. 相似文献
1000.
N.G. Ptitsyna V.V. Kasinskii G. Villoresi N.N. Lyahov L.I. Dorman N. Iucci 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,42(9):1510-1514
Intense geomagnetically induced currents (GIC) can hamper rail traffic by disturbing signaling and train control systems. GIC threats have been a concern for technological systems at high-latitude locations due to geomagnetic disturbances driven by substorm expansion electrojet or convection electrojet intensifications. However, other geomagnetic storm processes such as storm sudden commencement (SSC) and geomagnetic pulsations can also cause GIC concerns for technological systems. We present in this paper the first evidence based on statistical data for links between geomagnetic disturbances and faulty operations (anomalies) in the functioning of railway automatics and telemetry. We analyze anomalies of automatic signaling and train control equipment which occurred in 2004 on the East-Siberian Railway (corrected geomagnetic latitude m = 46–51°N and longitude λm = 168–187°E). Our results reveal a seasonal effect in the number of anomalies per train similar to the one observed in geomagnetic activity (Kp, Ap, Dst indices). We also found an increase by a factor of 3 in the total duration of daily anomalies during intense geomagnetic storms (local geomagnetic index specific to Siberian Observatory Amax > 30), with a significant correlation between the daily sum of durations of anomalies with geomagnetic activity. Special attention was paid to failures not related to recognized technical malfunctions. We found that the probability of these failures occurring in geomagnetically disturbed periods was 5–7 times higher than the average anomaly occurrence. 相似文献