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271.
272.
273.
A full color active-matrix liquid crystal display (AMLCD) with night-vision-goggle (NVG) compatibility is reported. The display is a 5-in-diagonal high-resolution triad (RGB) color pixel with 80×108 color groups per inch (H/V). It has a specially designed high-brightness backlight with low profile and the above-mentioned NVG characteristics. The color coordinates of the unit are almost identical to those of the display without NVG filter, preserving the red color coordinates. This display has full avionic characteristics, such as high contrast at high ambient light and extended temperature range 相似文献
274.
The replacement of electrical lines and connectors by free space or guided-wave optics in high-performance digital systems is discussed. Components for such systems are considered, and prototype systems are described. Optical interconnections with only a laser, two lenses, and a detector are possible and such a free-space board-to-board interconnection has been demonstrated at 1 Gb/s with an average power dissipation of only about 40 mW 相似文献
275.
P. Lukáč A. Meňovský Z. Trojanová J. Krumpos 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(5):73-76
The crystal growth under near-zero gravity conditions may lead to materials of better crystalline and compositional perfection [1]. Unidirectional solidification of metals is a part of Czechoslovak programme on space research within the framework of Interkosmos [2]. On the model-like systems of metals grown in the space we want to study the effect of foreign atoms on the surface tension and the lattice defects density. The objectives of our ground-based and space experiments are discussed. 相似文献
276.
M.-J. Martres B.E. Woodgate N. Mein Z. Mouradian J. Rayrole B. Schmieder G. Simon I. Soru-Escaut 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(7):5-10
According to the definition of the homology (optical) kept in reference, the homologous flares (HFl) may be observed wherever flares occur. The supposed supplementary preflaring conditions to have HFl may be either that the preflaring conditions have not been destroyed by the first flare (and then what mechanism has stopped the first and triggered the second ?) or that the preflaring conditions have been destroyed and rebuilt (and then, how ?). The analysis of data related to some selected active regions AR by the members of the working group, and the earlier works on HFl, may be used simultaneously to investigate the differences between one set of HFl and the others, the location of their sites and the evolution of HFl productive AR. This study brings the appearance of new footpoints from one flare to the following, the behaviour of cool arches (surging arches) leading to information on the changes of the magnetic configuration, and to peculiar characteristics of HFl, oif 2nd, 3rd in the time order concerning the chromospheric transition zone or coronal regions. The time delay between two consecutive homologous flares appears very quickly as an essential parameter to study homology. It was found that every set of flares (same type of site) is able to produce “rafales” of homologous flares, i.e. two, three, four, oir more flares with Δt in the range of one hour or less. The observations show no great chantes in macroscopic photospheric patterns (B, V) during this H flaring period. They lead to compare their temporal variation curves of flare brightness. A quantitative brightness parameter of homology relation has been defined. Some scale changes have also been detected in the dynamic spectrum of the site, and it is in good agreement with a very interesting theoretical suggestion made by P. Sturrock to produce such “rafales”. It may be shown that the closely consecutive time-homologous flares (CCHF) or “rafales” represent a good tool to analyse the critical conditions related to the origin and the amount of energy, mechanism of storage and release, necessary and, perhaps, sufficient conditions. New statistical results, applied to the different selected homologous flare active regions are presented and show the existence in homologous flaring areas of a “pivot” of previous filaments interpreted as a signature of an anomaly in the Solar rotation. 相似文献
277.
P Jiang S Fu H Cang X Wang Q Ren Y Yuan T Meng H Kang J Hu C Chen Z Yang R Bi 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,32(2):243-249
A Controllable and Observable Protein Crystallization Facility (ACOP) was developed in 1999 for space experiment in the Get Away Special canister of Space Shuttle. To regulate the vapor diffusion rate, in a crystallization chamber, five cells each containing precipitant solution of different concentrations, exposed to one protein cell in turn. Five layers of chambers were overlapped coaxially. The crystallization process was observed and recorded by digital cameras. Structure of facility and result of image sequence were given. 相似文献
278.
Mutagenic effects of heavy ion radiation in plants. 总被引:5,自引:0,他引:5
M Mei H Deng Y Lu C Zhuang Z Liu Q Qiu Y Qiu T C Yang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(10):363-372
Genetic and developmental effects of heavy ions in maize and rice were investigated. Heavy particles with various charges and energies were accelerated at the BEVALAC. The frequency of occurrence of white-yellow stripes on leaves of plants developed from irradiated maize seeds increased linearly with dose, and high-LET heavy charged particles, e.g., neon, argon, and iron, were 2-12 times as effective as gamma rays in inducing this type of mutation. The effectiveness of high-LET heavy ion in (1) inhibiting rice seedling growth, (2) reducing plant fertility, (3) inducing chromosome aberration and micronuclei in root tip cells and pollen mother cells of the first generation plants developed from exposed seeds, and (4) inducing mutation in the second generation, were greater than that of low-LET gamma rays. All effects observed were dose-dependent; however, there appeared to be an optimal range of doses for inducing certain types of mutation, for example, for argon ions (400 MeV/u) at 90-100 Gy, several valuable mutant lines with favorable characters, such as semidwarf, early maturity and high yield ability, were obtained. Experimental results suggest that the potential application of heavy ions in crop improvement is promising. RFLP analysis of two semidwarf mutants induced by argon particles revealed that large DNA alterations might be involved in these mutants. 相似文献
279.
E. S. Andreeva M. B. Gokhberg V. E. Kunitsyn E. D. Tereshchenko B. Z. Khudukon S. L. Shalimov 《Cosmic Research》2001,39(1):10-14
Long-lived local disturbances of the ionospheric density over the site of ground industrial explosions were detected by the ionosphere radiotomography method. It is assumed that the density anomalies arise because of the initiation of vortex motion in a neutral component after acoustic impulse passage. 相似文献
280.
J. Eró K. Kecskeméty T. Kovács G. Kozma I. Náday A. Somogyi L. Szabó I. T-Szücs A. Zarándy 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(3):173-176
A charged particle semiconductor-telescope is under construction in the CRIP, Budapest, to measure fluxes of 4–30 MeV/AMU protons, alphas, and M nuclei in interplanetary space. Identification and counting of particles are made on-board using microprocessor techniques. Details including some new ideas on economical coding of information and design of electronics are given. 相似文献