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981.
ABSTRACTMuch has changed since the first mapping of single-sex couples and families from the 2006 Australian census. An increasing willingness to allow their identification in the census has accompanied increasing public acceptance of same-sex couples culminating in significant support for legalising same-sex marriage in a 2017 national survey. Technological advances permit complex cross-tabulations of Australian census data and more detailed characterisations of same-sex couples. New geographies differentiate between male and female couples with children, showing same-sex couples are not just a feature of some inner-city areas, though these remain important, but also of suburban, regional and some rural areas. Drawing on the 2016 census, contemporary geographies of same-sex couples with and without children in Australia and changes over the past decade in Sydney are analysed at a time of increased interest in this demographic. 相似文献
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983.
984.
Frank A. van den Heuvel 《ISPRS Journal of Photogrammetry and Remote Sensing》1998,53(6):354-368
Photogrammetry has many advantages as a technique for the acquisition of three-dimensional models for virtual reality. But the traditional photogrammetric process to extract 3D geometry from multiple images is often considered too labour-intensive. In this paper a method is presented with which a polyhedral object model can be efficiently derived from measurements in a single image combined with geometric knowledge on the object. Man-made objects can often be described by a polyhedral model and usually many geometric constraints are valid. These constraints are inferred during image interpretation or may even be extracted automatically. In this paper different types of geometric constraints and their use for object reconstruction are discussed. Applying more constraints than needed for reconstruction will lead to redundancy and thereby to the need for an adjustment. The redundancy is the basis for reliability that is introduced by testing for possible measurement errors. The adjusted observations are used for object reconstruction in a separate step. Of course the model that is obtained from a single image will not be complete, for instance due to occlusion. An arbitrary number of models can be combined using similarity transformations based on the coordinates of common points. The information gathered allows for a bundle adjustment if highest accuracy is strived for. In virtual reality applications this is generally not the case, as quality is mainly determined by visual perception. A visual aspect of major importance is the photo-realistic texture mapped to the faces of the object. This texture is extracted from the same (single) image. In this paper the measurement process, the different types of constraints, their adjustment and the object model reconstruction are treated. A practical application of the proposed method is discussed in which a texture mapped model of a historic building is constructed and the repeatability of the method is assessed. The application shows the feasibility of the method and the potential of photogrammetry as an efficient tool for the production of 3D models for virtual reality applications. 相似文献
985.
Frank T. Howell 《Geological Journal》1971,7(2):329-334
Continuous seismic profile devices, modified for use in freshwater have been used on Windermere to determine the total thickness of lakebed sediments and the morphology of the underlying bedrock. The survey detected two overdeepened irregularly shaped rock basins. The northerly one approaches 110 feet (34 m) below sea level and contains 70 feet (21 m) of sediment. The corresponding dimensions of the Southern basin are 120 feet (37 m) and 130 feet (40 m) respectively. Glacial scouring is postulated as the origin of the rock basins. Some profiles show two types of sediment; the higher parts of which are known to be Post Glacial. 相似文献
986.
Frank O. Bryan 《Dynamics of Atmospheres and Oceans》1997,25(3):191-216
In this study we examine the axial angular momentum balance of a non-eddy-resolving global ocean general circulation model, from the perspective of the geographical and seasonal variability of angular momentum and from the perspective of the torques acting on the ocean through its surfaces. Our purpose is to provide an estimate of the magnitude of the seasonal storage of angular momentum in the ocean and hence the oceanic excitation of variability in length of day, and to elucidate the role of the ocean in transferring angular momentum between the atmosphere and the Earth's crust. We provide an assessment of the reliability of the model results by examining the sensitivity of the angular momentum and torque distributions to several model parameters.Although the Southern Ocean region containing the Antarctic Circumpolar Current (ACC) makes the largest contribution to both the annual mean oceanic angular momentum and its seasonal variability, inclusion of the rest of the world ocean reduces both of these quantities to about two-thirds of the value of the Southern Ocean alone. The annual, global mean angular momentum is found to be insensitive to most model choices except for the isopycnal diffusivity. The seasonal variability, on the other hand, is insensitive to the isopycnal diffusivity, but sensitive to the smoothness of the representation of topography and moderately sensitive to horizontal and vertical friction parameterizations. The torque balance at all latitudes, including within the Antarctic circumpolar belt, is between wind stress and bottom pressure torques. Horizontal friction torques are small but non-negligible. Bottom friction and storage of angular momentum are negligible in angular momentum budgets on seasonal time scales. Two commonly used wind stress climatologies, one based on historical marine meteorological observations and the other based on operational weather analyses, differ in the sign of the globally integrated wind stress torque. 相似文献
987.
Mingyu Yang Tracy D. Frank Christopher R. Fielding Megan E. Smith Peter K. Swart 《Sedimentology》2020,67(2):721-741
Inorganic aragonite occurs in a wide spectrum of depositional environments and its precipitation is controlled by complex physio-chemical factors. This study investigates diagenetic conditions that led to aragonite cement precipitation in Cenozoic glaciomarine deposits of McMurdo Sound, Antarctica. A total of 42 sandstones that host intergranular cement were collected from the CIROS-1 core, located proximal to the terminus of Ferrar Glacier. Standard petrography, Raman spectroscopy and electron microprobe analysis reveal a prominent aragonite cement phase that occurs as a pore-filling blocky fabric throughout the core. Oxygen isotope compositions (δ18O = −30·0 to −8·6‰ Vienna Pee-Dee Belemnite) and clumped isotope temperatures (TΔ47 = 13·1 to 31·5°C) determined from the aragonite cements provide precise constraints on isotopic compositions (δ18Ow) of the parent fluid, which mostly range from −10·8 to −7·2‰ Vienna Standard Mean Ocean Water. The fluid δ18Ow values are consistent with those of pore water, previously identified as cryogenic brine in the nearby AND-2A core. Petrographic and geochemical data suggest that aragonite cement in the CIROS-1 core precipitated from a similar brine. The brine likely formed and infiltrated sediments in flooded glacial valleys along the western margin of McMurdo Sound during the middle Miocene Climatic Transition, and subsequently flowed basinward in the subsurface. Consequently, the brine forms as a longstanding subsurface fluid that has saturated Cenozoic sediments below southern McMurdo Sound since at least the middle Miocene. Aragonite cementation in the CIROS-1 core is interpreted to reflect its proximal position to sites of brine formation and greater likelihood of experiencing brines with sustained high carbonate saturation states and Mg/Ca ratios. This unusual occurrence expands the range of known natural occurrences of aragonite cement. Given the potential for cryogenic brine formation in glaciomarine settings, blocky aragonite, as the end member of the spectrum of aragonite cement morphology, may be more widespread in glaciomarine sediments than currently thought. 相似文献
988.
Laurent Andre Monika A.M. Kedziorek Alain C.M. Bourg Frank Haeseler Denis Blanchet 《Journal of Hydrology》2009,370(1-4):1-8
Soils need to be thoroughly investigated regarding their potential for the natural attenuation of non-aqueous phase liquids (NAPL). Laboratory investigations truly representative of degradation processes in field conditions are difficult to implement for porous media partially saturated with water, NAPL and air. We propose an innovative protocol to investigate degradation processes under steady-state vadose zone conditions. Experiments are carried out in glass columns filled with a sand and, as bacteria source, a soil from a diesel-fuel-polluted site. Water and NAPL (n-hexadecane diluted in heptamethylnonane (HMN)) are added to the porous medium in a two-step procedure using ceramic membranes placed at the bottom of the column. This procedure results, for appropriate experimental conditions, in a uniform distribution of the two fluids (water and NAPL) throughout the column. In a biodegradation experiment non-biodegradable HMN is used to provide NAPL mass, while keeping biodegradable n-hexadecane small enough to monitor its rapid degradation. Biodegradation is followed as a function of time by measuring oxygen consumption, using a respirometer. Degradative activity is controlled by diffusive transfers in the porous network, of oxygen from the gas phase to the water phase and of n-hexadecane from the NAPL phase to the water phase. 相似文献
989.
Polyphase Tectonics through subsidence analysis: the Oligo-Miocene Venetian and Friuli Basin, north-east Italy 总被引:1,自引:0,他引:1
Subsidence and provenance analysis has been used as a tool to quantify and discriminate the role of tectonics and eustasy in the Veneto and Friuli Basin, north-east Italy, using 17 sections distributed along east–west-trending outcrops of Oligo-Miocene deposits. The basin can be considered a two-phase foreland; first, during late Oligocene to Langhian with respect to the NW–SE-trending Dinaric Chain, and then with respect to the south-vergent South-Alpine Chain.The clastic succession is up to 4000 m thick, and was deposited in a generally shallow-marine to nonmarine environment. Subsidence diagrams reconstructed for each section and E–W subsidence profiles indicate a compound effect of the Dinaric and South-Alpine tectonics as well as interference with eustatic sea-level changes.During the Oligocene and the early Miocene, the cycles recognized within the basin approximately match sea-level curves, the inferred cyclicity being primarily eustatic. However, the westward migration of the sedimentary depocentre during the same interval of time indicates activity of Dinaric thrusts.From Burdigalian (20 Ma) onwards, differential subsidence between the northernmost and the southernmost sectors of the basin suggests initiation of South-Alpine uplift in the frontal parts. During Tortonian and early Messinian uplift, erosion and southward migration of the thrust system was associated with the progressive closure of the basin from open marine influence. During Messinian sea-level drop, up to 2500 m of alluvial sediments were deposited at the same time as the South-Alpine thrusts were emerging, as confirmed by progressive angular unconformities within the continental succession. 相似文献
990.