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81.
Assessment of groundwater recharge processes through karst vadose zone by cave percolation monitoring 下载免费PDF全文
Amaël Poulain Arnaud Watlet Olivier Kaufmann Michel Van Camp Hervé Jourde Naomi Mazzilli Gaëtan Rochez Romain Deleu Yves Quinif Vincent Hallet 《水文研究》2018,32(13):2069-2083
Recharge processes of karst aquifers are difficult to assess given their strong heterogeneity and the poorly known effect of vadose zone on infiltration. However, recharge assessment is crucial for the evaluation of groundwater resources. Moreover, the vulnerability of karst aquifers depends on vadose zone behaviour because it is the place where most contamination takes place. In this work, an in situ experimental approach was performed to identify and quantify flow and storage processes occurring in karst vadose zone. Cave percolation monitoring and dye tracing were used to investigate unsaturated zone hydrological processes. Two flow components (diffuse and quick) were identified and, respectively, account for 66% and 34% of the recharge. Quickflow was found to be the result of bypass phenomenon in vadose zone related to water saturation. We identify the role of epikarst as a shunting area, most of the storage in the vadose zone occurring via the diffuse flow component in low permeability zones. Relationship between rainfall intensity and transit velocity was demonstrated, with 5 times higher velocities for the quick recharge mode than the diffuse mode. Modelling approach with KarstMod software allowed to simulate the hybrid recharge through vadose zone and shows promising chances to properly assess the recharge processes in karst aquifer based on simple physical models. 相似文献
82.
Carl Spandler Jörg Hermann Kevin Faure John A. Mavrogenes Richard J. Arculus 《Contributions to Mineralogy and Petrology》2008,155(2):181-198
The transfer of fluid and trace elements from the slab to the mantle wedge cannot be adequately explained by simple models
of slab devolatilization. The eclogite-facies mélange belt of northern New Caledonia represents previously subducted oceanic
crust and contains a significant proportion of talc and chlorite schists associated with serpentinite. These rocks host large
quantities of H2O and CO2 and may transport volatiles to deep levels in subduction zones. The bulk-rock and stable isotope compositions of talc and
chlorite schist and serpentinite indicate that the serpentinite was formed by seawater alteration of oceanic lithosphere prior
to subduction, whereas the talc and chlorite schists were formed by fluid-induced metasomatism of a mélange of mafic, ultramafic
and metasedimentary rocks during subduction. In subduction zones, dehydration of talc and chlorite schists should occur at
sub-arc depths and at significantly higher temperatures (∼ 800°C) than other lithologies (400–650°C). Fluids released under
these conditions could carry high trace-element contents and may trigger partial melting of adjacent pelitic and mafic rocks,
and hence may be vital for transferring volatile and trace elements to the source regions of arc magmas. In contrast, these
hybrid rocks are unlikely to undergo significant decarbonation during subduction and so may be important for recycling carbon
into the deep mantle.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
83.
A Dinis F Alves C Nicolau C Ribeiro M Kaufmann A Cañadas 《African Journal of Marine Science》2016,38(2):151-160
The bottlenose dolphin Tursiops truncatus is one of the most frequently sighted cetacean species in the Madeira Archipelago (North-East Atlantic); however, little is known about its population ecology in these waters. Photo-identification undertaken during systematic, non-systematic and opportunistic surveys conducted between 2001 and 2012 was used to assess group dynamics, site fidelity, residency and movement patterns of bottlenose dolphins in the archipelago. Three different patterns of residency were assigned, based on individual sighting histories. Group size ranged between 2 and 90 individuals (median 12), with no significant monthly difference in group size. All resident dolphins formed a core, complex network with migrant and transient dolphins. In contrast, satellite clusters were formed exclusively by transient individuals. The lagged identification rate (LIR) model indicated that a dolphin remained in the area for an average of 90 days, whereas the average time an individual spent outside the study area was approximately 313 days. The Madeira Archipelago appears to be only a section of a much larger home range for this population, with the dolphins exhibiting three different patterns of occurrence that associate with each other. The information gained about this poorly studied population contributes to the overall knowledge of bottlenose dolphins in insular oceanic habitats. 相似文献
84.
A Spatial Data Infrastructure Approach for the Characterization of New Zealand's Groundwater Systems 总被引:1,自引:0,他引:1 下载免费PDF全文
Alexander Kmoch Hermann Klug Alistair B. H. Ritchie Jochen Schmidt Paul A. White 《Transactions in GIS》2016,20(4):626-641
The future information needs of stakeholders for hydrogeological and hydro‐climate data management and assessment in New Zealand may be met with an Open Geospatial Consortium (OGC) standards‐compliant publicly accessible web services framework which aims to provide integrated use of groundwater information and environmental observation data in general. The stages of the framework development described in this article are search and discovery as well as data collection and access with (meta)data services, which are developed in a community process. The concept and prototype implementation of OGC‐compliant web services for groundwater and hydro‐climate data include demonstration data services that present multiple distributed datasets of environmental observations. The results also iterate over the stakeholder community process and the refined profile of OGC services for environmental observation data sharing within the New Zealand Spatial Data Infrastructure (SDI) landscape, including datasets from the National Groundwater Monitoring Program and the New Zealand Climate Database along with datasets from affiliated regional councils at regional‐ and sub‐regional scales. With the definition of the New Zealand observation data profile we show that current state‐of‐the‐art standards do not necessarily need to be improved, but that the community has to agree upon how to use these standards in an iterative process. 相似文献
85.
The first observation of a solar burst with millisecond time resolution at = 3.3 mm was obtained on 21 May, 1984. The time-scale of the millimetric pulses durations was of about 60 ms. The possible strong correlation between pulsed emission at 3.3 mm and hard X-rays is discussed.Proceedings of the Workshop on Radio Continua during Solar Flares, held at Duino (Trieste), Italy, 27–31 May, 1985. 相似文献
86.
Hermann L. F. Meyer 《International Journal of Earth Sciences》1916,7(5-6):193-248
Ohne Zusammenfassung 相似文献
87.
88.
Hermann Freudenberg 《International Journal of Earth Sciences》1940,31(3-4):285-293
Ohne Zusammenfassung 相似文献
89.
Ohne Zusammenfassung 相似文献
90.