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951.
I.A. Zhulin V.M. Kostin I.A. Pimenov Ju.Ja. Ruzhin V.S. Skomarovsky Ju.M. Zhuchenko Ju.A. Romanovsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):319-323
Evidence for an enhancement of the electron flux associated with a barium chaped charge release from “SPOLOKH-2” rocket payload, launched from Volgograd (L = 2.2) on June 29, 1978, will be presented. There is also evidence for a periodic train of particle bursts occurring with about 11 second period during more than 100 seconds after the release. The observed phenomena is interpreted as a “trigger-effect”. 相似文献
952.
The detection performance of a single-channel MTI receiver with post-detection integration, for a Swerling I target, has been evaluated by a Monte Carlo simulation. It is shown that a fairly good approximation is obtained by applying the ?effective number of independent integrated samples? to the standard detection curves. The ?I-only? loss is about 2 dB for integration of more than 20 pulses; thus this receiver is acceptable if implementation constraints dictate it. 相似文献
953.
The mutual potential of 2 solid bodies is a function of the six parameters defining the relative position of these two bodies, it is not a function of only either 3 or 5 parameters as it is implicitly assumed in most studies.The sixth parameter, “the potential torsion” is related to the orientation of the two bodies around the axis of the two centers, its influence is small. An upper limit is given. 相似文献
954.
I. N. Toptyghin 《Space Science Reviews》1980,26(2):157-213
The theory and observational evidence pertaining to particle acceleration by shock waves in astrophysical objects and in space are systematized. Recent works showing observational and theoretical aspects of the problem dealing with shocks in turbulent media are emphasized. The acceleration of particles by shocks in turbulent media is observed in interplanetary space. This acceleration mechanism is of particular interest from the point of view of the origin of cosmic rays, providing the degree form of the spectrum. The index of the spectrum is close to the observable one for galactic cosmic rays. It depends slightly on specific conditions in the acceleration region. Electron and nucleus acceleration in supernova remnants and in radiogalaxies is discussed, and theory and observational data are compared. The theory of particle acceleration by supersonic turbulence is outlined. 相似文献
955.
L A Somova N S Pechurkin V I Polonsky T I Pisman A B Sarangova M Andre G M Sadovskaya 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,20(10):1939-1943
The effect has been studied of inoculation of seeds of wheat with two species of rhizospheric microorganisms--Pseudomonas fluorescens and Pseudomonas putida--on young plant growth with complete and with nitrogen deficit mineral nutrition. With complete mineral medium, plants grown from seeds inoculated with bacteria of Pseudomonas genus (experiment plants) have been found to have better growth over plants not inoculated with these bacteria (control plants). The experiment plants had increased transpiration and their biomass had higher organic nitrogen content. With nitrogen deficit medium, the plants inoculated with bacteria and those without them, have not revealed changes in growth. Neither case demonstrated competition of microorganisms with plants for nitrogen sources. 相似文献
956.
I. Apáthy I. Szemerey P. Bencze K. Kovács V. Afonin V. Bezrukih K. Gringauz N. Shutte 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(12):101-105
Ion temperature and total ion concentration measured on 25th October 1977 during the flight of the geophysical rocket “Vertical-6” are analyzed. The solar EUV fluxes determined in five wave-length bands with a photoelectron analyzer are also given. The observed anomalous variation of ion temperature between 700 and 900 km and the measured ion concentration can be explained, if the charge exchange reactions H+ ? O+ and diffusion are taken into account. 相似文献
957.
The effect of I F filter bandwidth to I F frequency ratio on the probability of error in a binary bandpass communication system with nonreturn-to-zero (NRZ) and split-phase (SP) signals is investigated. ed. Explicit results are given for the case when the bandpas I F filter is transformed from a single-pole low-pass filter. 相似文献
958.
I. Kimura H. Matsumoto K. Hashimoto T. Mukai R.A. Helliwell T.F. Bell U.S. Inan J.P. Katsufrakis 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):197-202
A Japanese magnetospheric satellite Jikiken (EXOS-B) was used to observe Siple transmissions and VLF emissions triggered by the Siple signals. Energetic particle fluxes were also observed at the same time. The first experiments were made during July, August and September in 1979 and the second experiments were made during December in 1979 and January in 1980. The Siple triggered emissions were observed in August. This report reviews the preliminary results. 相似文献
959.
The first 8.5m infrared heterodyne spectrometer has been constructed using tuneable semiconductor (PbSe) diode lasers and was used to measure absorption line profiles of N2O in the laboratory and black body emission from the Moon and from Mars. Spectral information was recorded over a 200 MHz bandwidth using an 8-channel filter bank. The resolution was 25 MHz (6 × 10–6
m) and the minimum detectable (black-body) power was 1 × 10–16 W for 8 min of integration. The results demonstrate the usefulness of heterodyne spectroscopy for the study of remote and local sources in the infrared.We wish to thank Dr Jack Butler and Craig Simpson (Arthur D. Little, Inc.) for their continuing (and successful) efforts to grow better diode lasers during the course of this experiment. We thank the National Radio Astronomy Observatory for the loan of a 40-channel filter bank and associated mini-computer.We thank en masse the dozens of people who loaned equipment to us for the duration of this experiment, and the commercial firms (especially Harshaw, Inc.) which expedited orders for crucial equipment. We thank Dr Bertram Donn, Dr Norman Ness, and Dr George Pieper for administrative, scientific, and financial support; and we thank Mr James Faris for technical assistance and Dr Sol Glicker for preparation of sample gas cells. We thank Dr Thomas Clark for providing the Kohoutek ephemeris, sighting printout, and predicted molecular line positions and for advice and the loan of some equipment. Finally, we wish to acknowledge the strong support accorded us by our wives and families who scarcely saw us during this period. 相似文献
960.
The objective of the Search for Extraterrestrial Intelligence (SETI) is to locate an artificially created signal coming from a distant star. This is done in two steps: (1) spectral analysis of an incoming radio frequency band, and (2) pattern detection for narrow-band signals. Both steps are computationally expensive and require the development of specially designed computer architectures. To reduce the size and cost of the SETI signal detection machine, two custom VLSI chips are under development. The first chip, the SETI DSP Engine, is used in the spectrum analyzer and is specially designed to compute Discrete Fourier Transforms (DFTs). It is a high-speed arithmetic processor that has two adders, one multiplier-accumulator, and three four-port memories. The second chip is a new type of Content-Addressable Memory. It is the heart of an associative processor that is used for pattern detection. Both chips incorporate many innovative circuits and architectural features. 相似文献