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241.
D Voeste L H Levine H G Levine V Blum 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):211-214
The Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) Mini-Module, a Space Shuttle middeck locker payload which supports a variety of aquatic inhabitants (fish, snails, plants and bacteria) in an enclosed 8.6 L chamber, was tested for its biological stability in microgravity. The aquatic plant, Ceratophyllum demersum L., was critical for the vitality and functioning of this artificial mini-ecosystem. Its photosynthetic pigment concentrations were of interest due to their light harvesting and protective functions. "Post-flight" chlorophyll and carotenoid concentrations within Ceratophyllum apical segments were directly related to the quantities of light received in the experiments, with microgravity exposure (STS-89) failing to account for any significant deviation from ground control studies. 相似文献
242.
V Blum 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(7):1683-1691
The Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) is an artificial aquatic ecosystem which contains teleost fishes, water snails, ammonia oxidizing bacteria and edible non-gravitropic water plants. It serves as a model for aquatic food production modules which are not seriously affected by microgravity and other space conditions. Its space flight version, the so-called C.E.B.A.S. MINI-MODULE was already successfully tested in the STS-89 and STS-90 (NEUROLAB) missions. It will be flown a third time in space with the STS-107 mission in January 2003. All results obtained so far in space indicate that the basic concept of the system is more than suitable to drive forward its development. The C.E.B.A.S. MINI-MODULE is located within a middeck locker with limited space for additional components. These technical limitations allow only some modifications which lead to a maximum experiment time span of 120 days which is not long enough for scientifically essential multi-generation-experiments. The first necessary step is the development of "harvesting devices" for the different organisms. In the limited space of the plant bioreactor a high biomass production leads to self-shadowing effects which results in an uncontrolled degradation and increased oxygen consumption by microorganisms which will endanger the fishes and snails. It was shown already that the latter reproduce excellently in space and that the reproductive functions of the fish species are not affected. Although the parent-offspring-cannibalism of the ovoviviparous fish species (Xiphophorus helleri) serves as a regulating factor in population dynamics an uncontrolled snail reproduction will also induce an increased oxygen consumption per se and a high ammonia concentration in the water. If harvesting locks can be handled by astronauts in, e. g., 4-week intervals their construction is not very difficult and basic technical solutions are already developed. The second problem is the feeding of the animals. Although C.E.B.A.S.-based aquaculture modules are designed to be closed food loop systems (edible herbivorous fish species and edible water plants) which are already verified on Earth this will not be possible in space without devices in which the animals are fed from a food storage. This has to be done at least once daily which would waste too much crew time when done by astronauts. So, the development of a reliable automated food dispenser has highest priority. Also in this case basic technical solutions are already elaborated. The paper gives a comprehensive overview of the proposed further C.E.B.A.S.-based development of longer-term duration aquatic food production modules. 相似文献
243.
The effects of microgravity on induced mutation in Escherichia coli and Saccharomyces cerevisiae. 总被引:6,自引:0,他引:6
A Takahashi K Ohnishi S Takahashi M Masukawa K Sekikawa T Amano T Nakano S Nagaoka T Ohnishi 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2001,28(4):555-561
We examined whether microgravity influences the induced-mutation frequencies through in vivo experiments during space flight aboard the space shuttle Discovery (STS-91). We prepared dried samples of repair-deficient strains and parental strains of Escherichia (E.) coli and Saccharomyces (S.) cerevisiae given DNA damage treatment. After culture in space, we measured the induced-mutation frequencies and SOS-responses under microgravity. The experimental findings indicate that almost the same induced-mutation frequencies and SOS-responses of space samples were observed in both strains compared with the ground control samples. It is suggested that microgravity might not influence induced-mutation frequencies and SOS-responses at the stages of DNA replication and/or DNA repair. In addition, we developed a new experimental apparatus for space experiments to culture and freeze stocks of E. coli and S. cerevisiae cells. 相似文献
244.
G S Nechitailo A L Mashinsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,20(10):1959-1965
The results of experiments aboard spacecraft demonstrated the dependence of the pattern of biological processes on microgravity and on the ability of biological objects to adapt themselves to new environmental conditions. This is of fundamental importance for solving theoretical and practical problems of space biology, or elaborating the theory of organism's behavior in weightlessness, and for elucidating the global mechanisms of the action of microgravity on living systems. 相似文献
245.
M. M. Freund T. Hirao T. Matsumoto S. Sato T. Watabe G. K. Brubaker L. Duband B. Grossman N. Larkin S. Lumetta A. E. Lange 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1993,13(12):505-508
We describe the design and calibration of the Far-Infrared Photometer (FIRP), one of four focal plane instruments on the Infrared Telescope in Space (IRTS). The FIRP will provide absolute photometry in four bands centered at 150, 250, 400, and 700 μm with spectral resolution λ/Δλ ≈ 3 and spatial resolution ΔΘ = 0.5 degrees. High sensitivity is achieved by using bolometric detectors operated at 300 mK in an AC bridge circuit. The closed-cycle 3He refrigerator can be recycled in orbit. A 2 K shutter provides a zero reference for each field of view. More than 10% of the sky will be surveyed during the ≈3 week mission lifetime with a sensitivity of <10−13 W·cm−2·sr−1 per 0.5 degree pixel. 相似文献
246.
D. Haegan M. Haiduc A. Marin E.E. Kovalev G.P. Hertzen S.A. Dashin A.M. Marenny 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(14):55-60
LET variation with the absorber thickness was measured by plastic detectors exposed on COSMOS-1129 satellite. 相似文献
247.
H. S. Hudson 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(13):247-250
HEAO-1 observed hard radiations (X- and gamma-rays) from a major solar flare on 11 July 1978. The observations showed gamma-ray line and continuum emission extending to the highest energy observed. The lines are identified with the 2.2 MeV line of deuterium formation and the 4.4 MeV line of inelastic scattering on 12C, both previously observed in the flares of August 1972 [1]. The 11 July flare was identified as a white-light flare by observations at Debrecen [2]. It thus provides the first opportunity for a detailed examination of white-light flare theories that depend upon proton heating of the photosphere. The line strength over a four-minute integration at 2.2 MeV was 1.00 ± 0.29 ph(cm2 sec)−1, and the gamma-ray emission (excluding the 2.2 MeV line which was appreciably delayed) lagged by less than 20 sec approximately after the hard X-ray and microwave fluxes. We conclude that the “second-stage” acceleration of high-energy solar particles must commence promptly after the impulsive phase. 相似文献
248.
V. Yurchyshyn Q. Hu R.P. Lepping B.J. Lynch J. Krall 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2007,40(12):1821-1826
Coronal mass ejections (CMEs) observed near the Sun via LASCO coronographic imaging are the most important solar drivers of geomagnetic storms. ICMEs, their interplanetary, near-Earth counterparts, can be detected in situ, for example, by the Wind and ACE spacecraft. An ICME usually exhibits a complex structure that very often includes a magnetic cloud (MC). They can be commonly modelled as magnetic flux ropes and there is observational evidence to expect that the orientation of a halo CME elongation corresponds to the orientation of the flux rope. In this study, we compare orientations of elongated CME halos and the corresponding MCs, measured by Wind and ACE spacecraft. We characterize the MC structures by using the Grad–Shafranov reconstruction technique and three MC fitting methods to obtain their axis directions. The CME tilt angles and MC fitted axis angles were compared without taking into account handedness of the underlying flux rope field and the polarity of its axial field. We report that for about 64% of CME–MC events, we found a good correspondence between the orientation angles implying that for the majority of interplanetary ejecta their orientations do not change significantly (less than 45 deg rotation) while travelling from the Sun to the near-Earth environment. 相似文献
249.
S.V. Chalov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2005,35(12):2106-2114
It may not be doubted anymore that anomalous cosmic rays (ACRs) are produced in the heliosphere from interplanetary pick-up ions through their acceleration at the solar wind termination shock. However, there is no general agreement in the community of heliospheric researchers concerning the mechanism of injection of the pick-up ions into the shock acceleration. We discuss here three possible ways for pick-up ions to be involved into the acceleration process at the termination shock: (1) preacceleration of pick-up ions in the whole region from the Sun up to the termination shock by solar wind turbulences and interplanetary shock waves, (2) local preacceleration of pick-up ions in a vicinity of the termination shock by shock surfing, and (3) formation of high-velocity tails in pick-up ion spectra consisting of secondary pick-up ions which are produced in the supersonic solar wind due to ionization of energetic neutral atoms entering from the inner heliosheath. 相似文献
250.
S Silverstone M Nelson A Alling J Allen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):69-75
For humans to survive during long-term missions on the Martian surface, bioregenerative life support systems including food production will decrease requirements for launch of Earth supplies, and increase mission safety. It is proposed that the development of "modular biospheres"--closed system units that can be air-locked together and which contain soil-based bioregenerative agriculture, horticulture, with a wetland wastewater treatment system is an approach for Mars habitation scenarios. Based on previous work done in long-term life support at Biosphere 2 and other closed ecological systems, this consortium proposes a research and development program called Mars On Earth(TM) which will simulate a life support system designed for a four person crew. The structure will consist of 6 x 110 square meter modular agricultural units designed to produce a nutritionally adequate diet for 4 people, recycling all air, water and waste, while utilizing a soil created by the organic enrichment and modification of Mars simulant soils. Further research needs are discussed, such as determining optimal light levels for growth of the necessary range of crops, energy trade-offs for agriculture (e.g. light intensity vs. required area), capabilities of Martian soils and their need for enrichment and elimination of oxides, strategies for use of human waste products, and maintaining atmospheric balance between people, plants and soils. 相似文献