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981.
S.M. Ivanova N.A. Brazhe O.G. Luneva Y.V. Yarlikova O.I. Labetskaya E.Y. Parshina A.A. Baizhumanov G.V. Maksimov B.V. Morukov 《Acta Astronautica》2011,68(9-10):1517-1522
We studied microfluidity and selective ion permeability of plasma membranes and O2-binding properties of erythrocytes of cosmonauts during early rehabilitation after a long-term space flight (LTSF). Microfluidity of plasma membranes in surface regions was found to undergo a reversible decrease during 13–15 days following LTSF, which was accompanied by a reversible increase in relative cholesterol content. Cosmonauts’ erythrocytes revealed an increased activity of Na/H-exchanger and KCa-channel as well as a decrease in number of discocytes and increase in number of echinocytes, stomatocytes and knizocytes. Total hemoglobin content as well as oxyhemoglobin content were lowered after the LTSF, while the affinity of hemoglobin to O2 was advanced. It is suggested that the changes in Hb properties, microfluidity and selective permeability of plasma membranes following the elevated cholesterol content in the membranes can decrease tissue supply with O2. 相似文献
982.
983.
Hristo S. Nikolov Doyno I. Petkov Nina Jeliazkova Stela Ruseva Kiril Boyanov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The aim of this research is to develop an effective approach being able to deal with the stochastic nature of remote sensing data. In order to achieve this objective it is necessary to structure the methodological knowledge in the area of data mining and reveal the most suitable methods for the prediction and decision support based on large amounts of multispectral data. The idea is to establish a framework by decomposing the task into functionality objectives and to allow the end-user to experiment with a set of classification methods and select the best methods for specific applications. As a first step, we compare our results from Bayesian classification based on non-parametric probability density estimates of the data to the results obtained from other classification methods. Tree scenarios are considered, making use of a small benchmark dataset, a larger dataset from Corine land cover project for Bulgaria and analyzing different features and feature selection methods. We show that the theoretically optimal Bayesian classification can also achieve optimal classification in practice and provides a realistic interpretation of the world where land cover classes intergrade gradually. 相似文献
984.
A. Iarocci P. Benedetti F. Caprara A. Cardillo F. Di Felice G. Di Stefano P. Drakøy R. Ibba M. Mari S. Masi I. Musso P. Palangio S. Peterzen G. Romeo G. Spinelli D. Spoto G. Urbini 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
Stratospheric balloons are powerful and affordable tools for a wide spectrum of scientific investigations that are carried out at the stratosphere level. They are less expensive compared to satellite projects and have the capability to lift payloads from a few kilograms to a couple of tons or more, well above the troposphere, for more than a month. Another interesting feature of these balloons, which is not viable in satellites, is the short turnaround time, which enables frequent flights. 相似文献
985.
W.Q. Gan Y.P. Li L.I. Miroshnichenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(6):908-913
The footpoint motions of flare hard X-ray (HXR) sources are directly related to the reconnection scenario of a solar flare. In this work, we tried to extract the information of footpoint motions for a number of flares observed with RHESSI. We found that the RHESSI flare results of the footpoint motions strongly support the classification proposed from the observations of YOHKOH/HXT. Furthermore, it is found that a flare can consist of two types of footpoint motions. We discussed the connections of the footpoint motions with the two-dimensional reconnection models. 相似文献
986.
K. Haijima K.G. Tanaka M. Fujimoto I. Shinohara 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(10):1643-1648
Recent two-dimensional (2-D) particle-in-cell (PIC) simulations have shown that there is a critical thickness of a current sheet, above which no significant saturation amplitude of the 2-D tearing (TI) mode can be expected. Here, we have introduced the initial electron temperature anisotropy (αe0 = Te⊥/Te|| > 1), which is known to raise significantly the linear growth rates, and inspected if αe0 > 1 can change the saturation level of the TI in a super-critical current sheet. Varying αe0 and D (D: the current sheet half-thickness) systematically, we have found that while αe0 boosts up the linear growth rate in both sub- and super-critical current sheets, macroscopic effects are obtained only in sub-critical current sheets, that is, energy transfer from the fastest growing short wavelength modes to longer wavelength modes are available only in the sub-critical regime. Since the critical thickness is a fraction of the ion inertial length, the tearing mode assisted by the electron temperature anisotropy alone, despite its significant boost in the linear growth rate, cannot be the agent for reconnection triggering in a current sheet of ion-scale thickness. 相似文献
987.
Results of processing the data of multi-frequency Doppler sounding of the low-latitude ionosphere are presented. Interesting
features in the behavior of time variations of the Doppler frequency shift are found. These features are interpreted as manifestations
of wave disturbances in the ionospheric plasma density. 相似文献
988.
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
989.
990.
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