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361.
Y. Kamotani M. Vargas S. Ostrach 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(5):37-40
The floating-zone method for crystal growth is studied in simulated low-gravity conditions by suspending a drop of fluid vertically between two circular rods and heating the upper rod with a heater. Flow and temperature oscillations are observed under certain conditions. The temperature oscillation level and the oscillation frequency are measured against the Marangoni number for several aspect ratios using hexadecane and Fluorinert as the test fluids. It is observed that, contrary to what has been believed, the Marangoni number is not the proper parameter to describe the onset of oscillation. 相似文献
362.
Y Ishikawa H Yoshida M Kinoshita A Murakami K Sugiura 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(7):1517-1527
Research of the effect of space environment on an ecosystem consisting of plants and animals is essential when they are to be positively used in space. Although there have been experiments on various organisms under space environment in the past, they mainly studied the effect of space environment on an individual organism or a single species. Microcosm is drawing attention as an experimental material of an ecosystem consisting of multiple species. The object in this research is to understand the nature of this network system called ecosystem. Thus, a mixed microorganism culturing system consisting of three types of microorganisms which form a minimum food chain system as a closed ecosystem (chlorella as the producer, bacteria as the decomposer, and rotifer as the consumer) was taken for the subject, on which to research the universal characteristics of ecosystems. From the results of experiments under the terrestrial environment, formation of colonies, which is an ecological structure, has been observed at its mature stage. The organisms form an optimal substance circulation system. Therefore, formation of colonies in simulation models is important. Many attempts have been made to create ecosystem models. For example, the Lotka-Volterra model forms a simultaneous equation with the differential equation expressing predator and prey relationship and many numerical calculations have been conducted on various ecosystems based on expanded L-V models. Conventionally, these top-down methods have been used. However, since this method only describes the average concentration of organisms that are distributed uniformly throughout the system and cannot express the spatial structure of the system, it was difficult to express ecosystem structures like colonies and density distributions. In actual ecosystems, there is heterogeneity in the number of individuals and in substance density, and this is thought to have great significance in ecosystems. Consequently, an individual-based model was used that applies rules to predator-prey relationship, suppression, production, self suppression, etc., of each species. It enabled the emergence of the overall system only by its local rules, and it was possible to reproduce colony generation. In addition, the transition and the ratio of populations for each species match well with experimental results. 相似文献
363.
H. Akiyama J. Nishimura M. Namiki Y. Okabe Y. Matsuzaka H. Hirosawa 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(6):97-100
A new static-launch method that we have developed as an improvement of our former method is described. The key procedure is to extend a whole balloon vertically upon the launcher before release, with squeezing the top bubble of the balloon by a soft collar. The new method improved the capability for heavier payload significantly. In 1981, 15 balloons, ranging from 5,000 m3 to 50,000 m3 in volume with a total lift from 150 kg to 650 kg, were launched by this new method successfully. 相似文献
364.
M. A. Hapgood T. G. Dimbylow D. C. Sutcliffe P. A. Chaizy P. S. Ferron P. M. Hill X. Y. Tiratay 《Space Science Reviews》1997,79(1-2):487-525
The Joint Science Operations Centre (JSOC) has been established to provide the operational interface between the Instrument Principal Investigators (PIs) and the European Space Operations Centre (ESOC). Its key task will be to merge inputs from the Cluster instrument teams and to generate the coordinated command schedule for operation of the scientific payload. In addition, it will collect and process data needed to plan those operations and will monitor the performance of the mission and individual instruments. This paper outlines the JSOC subsystems that have been built to carry out these tasks and highlights points of scientific or technical interest within these systems. 相似文献
365.
Y. Nakagawa 《Space Science Reviews》1976,19(4-5):459-473
The optical observations and analyses of the flares of August 1972 are reviewed with emphasis on their dynamics. In particular, various assessments are made of possible quantitative interpretation of observed data. Specific topics considered are the storage and release of magnetic energy, triggering mechanisms, particle acceleration and magnetic field reconnection, and coronal and solar wind responses. Supplemental discussions on possible future direction of research are presented, illustrating the need for examination of the storage and release of flare energy in the lower solar atmosphere.On leave from the High Altitude Observatory.The National Center for Atmospheric Research is sponsored by the National Science Foundation. 相似文献
366.
Savina VP Mikos KN Ryzhkova VE Gorshunova AI Nefyodov YG Lepsky AA Aksyonov VV 《Acta Astronautica》1979,6(10):1251-1254
The Soyuz 22 space cabin atmosphere was studied for volatile organic trace contaminants. By gas chromatography the following constituents were identified: methane, ethane, heptane, methanol, ethanol, n-propanol, acetaldehyde, acetone, ethyl benzene. Except for acetone, concentrations of the above compounds were close to the values determined in the mock-up experiments. 相似文献
367.
M B Simakov E A Kuzicheva A E Dodonova NYaAntropov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,19(7):1063-1066
The present experiment indicates that oligopeptides are easily produced in solid state from mixtures of simple amino acids by irradiating with high energy charged particles. We investigated such amino acids and their mixtures as tryptophan, tyrosine and glycine. The thin films was irradiated with protons (6.6 MeV). Such dipeptides as Trp-Trp, Gly-Tyr, Tyr-Gly, and Tyr-Tyr have been detected as products of irradiation. Cosmic rays might be an effective energy source for abiotic formation of bioorganic compounds on the surface of small bodies in the solar system on early stage of formation of planets as well as at present day. 相似文献
368.
Pelletier M. Cummins J. Delisle G.Y. 《IEEE transactions on aerospace and electronic systems》1977,(3):318-321
The phases of the radiation fields in a multibeam antenna are analyzed and their relations to the feed network are established. A method of phase control is proposed and applied to the case of cophasal beams radiated from an array for which the feed network is a lossless Butler matrix. 相似文献
369.
A.J. Merkys R.S. Laurinavichius O.Y. Rupainene D.V. Shvegzhdene A.V. Yaroshius 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(14):109-116
Gravity may influence different aspects of plant activity. The present report deals with two questions: gravity as an ecological factor determining spatial orientation of plant growth; and second, a possible requirement for gravity in the process of normal growth, morphogenesis and generative development of plants. 相似文献
370.
Stüeken E. E. Som S. M. Claire M. Rugheimer S. Scherf M. Sproß L. Tosi N. Ueno Y. Lammer H. 《Space Science Reviews》2020,216(3):1-17
Space Science Reviews - The Ionospheric Connection Explorer (ICON) mission makes measurements in near-Earth space that provide knowledge of the state of the ionosphere. From the vantage of... 相似文献