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931.
J. C. Archer G. T. Murauskas F. M. Shelley P. J. Taylor E. R. White 《The Professional geographer》1985,37(3):279-287
County scale cartographic analysis of Ronald Reagan's reelection landslide of 1984 shows the geographical core of his electoral strength to be in the Interior West, non-ethnic areas of the South, and suburbs across the nation. Examination of spatio-temporal variations using factor analysis at a state scale shows this to be a continuation and reinforcement of recent electoral-geographical cleavages. T-mode factor analysis traces the emergence of a contemporary Conservative Normal Vote during the past several presidential elections and the manifestation of this cleavage in the election of 1984. 相似文献
932.
933.
934.
Stuart Ross Taylor 《Earth, Moon, and Planets》1973,7(1-2):181-195
The principal rock types in the highlands are highland basalt (gabbroic anorthosite) with 28% Al2O3 and low K Fra Mauro basalt with 18% Al2O3. The chemistry of the highland soils and breccias can be represented by simple mixing models involving these rock types as major constituents. The mixing occurred during the intense highland cratering. Layering observed at the Apennine Front is interpreted as produced the Serenitatis basin collision. The plains-forming Cayley Formation and the Descartes Formation are not volcanic, but are derived from pre-existing highland crust.Although the overall chemical composition of the Moon has been affected by pre-accretion processes (e.g. loss of volatile elements), the composition of the highlands is mainly the result of postaccretion melting and element fractionation. Thus the individual rock types show involatile element distribution patterns, relative to primitive abundances, indicative of solid-liquid equilibria, evidence of post-accretion lunar igneous activity.The chemistry of the primitive green glass component (15426) indicates that the abundance of the involatile elements (REE, Ba, Zr, Hf, Th and U) in the source regions is at most only 2–3 times the abundances in chondrites.Paper dedicated to Professor Harold C. Urey on the occasion of his 80th birthday on 29 April, 1973. 相似文献
935.
936.
Taylor G.W. Burns J.R. Kammann S.A. Powers W.B. Welsh T.R. 《Oceanic Engineering, IEEE Journal of》2001,26(4):539-547
The Energy Harvesting Eel (Eel) is a new device that uses piezoelectric polymers to convert the mechanical flow energy, available in oceans and rivers, to electrical power. Eel generators make use of the regular trail of traveling vortices behind a bluff body to strain the piezoelectric elements; the resulting undulating motion resembles that of a natural eel swimming. Internal batteries are used to store the surplus energy generated by the Eel for later use by a small, unattended sensor or robot. Because of the properties of commercially available piezoelectric polymers, Eels will be relatively inexpensive and are easily scaleable in size and have the capacity to generate from milli-watts to many watts depending on system size and flow velocity of the local environment. A practical Eel structure has been developed that uses the commercially available piezoelectric polymer, PVDF. Future Eels may use more efficient electrostrictive polymer. Every aspect of the system from the interactions between the hydrodynamics of the water flow and structural elements of the Eel, through the mechanical energy input to the piezoelectric material, and finally the electric power output delivered through an optimized resonant circuit has been modeled and tested. The complete Eel system, complete with a generation and storage system, has been demonstrated in a wave tank. Future work on the Eel will focus on developing and then deploying a small, lightweight, one-watt power generation unit, initially in an estuary and then subsequently in the ocean. Such Eels will have the ability to recharge batteries or capacitors of a distributed robotic group, or remote sensor array, thus extending the mission life indefinitely in regions containing flowing water 相似文献
937.
Abstract— ‐Mercury has widespread plains deposits proposed to be volcanic in origin. In a Mariner 10 color‐derived parameter image, sensitive to FeO and maturity, these volcanic plains have a value equivalent to, or slightly elevated above, the hemispheric average, thus implying FeO equivalent to, or slightly less than, the hemispheric average (~3 wt% FeO). Since FeO has a solid/liquid distribution coefficient ~1 during partial melting, we estimate the mantle of Mercury to have an FeO abundance equal to the lava flows. This is consistent with models that predict Mercury was assembled from planetesimals formed near the planet's current position. This new estimate of Mercury's bulk FeO (~3 wt%) is consistent with data for the other terrestrial planets that suggest there was a radial gradient in FeO in the solar nebula. 相似文献
938.
939.
Shaun Cole Peder Norberg Carlton M. Baugh Carlos S. Frenk Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Nicholas Cross Gavin Dalton Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole Jackson Ofer Lahav Ian Lewis Stuart Lumsden Steve Maddox Darren Madgwick John A. Peacock Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2001,326(1):255-273
940.
C. H. TAYLOR Methodological issues associated with isotopic hydrograph separations (IHSs) in built-up environments are explored using results from the 1990 spring melt in a suburban basin in Peterborough, Ontario, Canada. The hetrogeneous nature of suburban environments complicates the selection of appropriate isotopic signatures for event and pre-event waters. Near-stream groundwater δ18O sampled from wells was poorly mixed, such that the pre-event water signature was best characterized by δ18O in pre-melt baseflow or discharge from a headwater spring. The event water signature during snowmelt can be characterized using δ18O in the pre-melt snowpack, surface runoff samples or meltwater from lysimeters. However, the use of snowpack δ18O may be inappropriate in suburban basins where meltwater from thin snowcover may exhibit pronounced responses to δ18O in rainfall contributions. Intensive sampling of the spatial variability of runoff or meltwater δ18O may be required to characterize the average event water signature adequately. Rainfall δ18O provided an appropriate event water signal during a large rain on snow event, and differences between this IHS and one generated using an event water signature that included meltwater contributions from snow-covered surfaces were within the uncertainty attributable to the analytical error in δ18O values. Event water supplied 55-63% of the peak discharge and 48-58% of total runoff from the basin during the melt, which is consistent with the fraction of the basin that has been developed. These results contrast with IHSs conducted in forested basins that suggest that stormflow is dominated by pre-event water contributions. 相似文献