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111.
Guo Congcong Bai Xiaoyun Abdullah Al Mamun Sikder Mohammad Nurul Azim Xu Henglong 《Ocean Science Journal》2019,54(1):87-95
Ocean Science Journal - Biological trait analysis (BTA) of protozoan communities has been used a useful bioindicator of environmental quality status in marine ecosystems. To determine the optimal... 相似文献
112.
Soloviev An. A. Soloviev Al. A. Gvishiani A. D. Nikolov B. P. Nikolova Yu. I. 《Izvestiya Atmospheric and Oceanic Physics》2018,54(9):1363-1373
Izvestiya, Atmospheric and Oceanic Physics - Zones of higher seismic hazard occupy about 20% of Russia’s territory, and 5% are characterized by extremely high hazard. These latter are, in... 相似文献
113.
Impacts of Anthropogenic Land Use Changes on Nutrient Concentrations in Surface Waterbodies: A Review 总被引:1,自引:0,他引:1 下载免费PDF全文
Increased population leads to land use (LU) changes from natural to urban and agricultural LU. These disturbances not only decrease the natural treatment potential but they also worsen surface water quality (SWQ). The aim of this review is to assess studies about impacts of anthropogenic LU changes on levels of nutrient concentrations in surface waterbodies, highlighting the important parameters needed for an integrated simulation. The results reported in the literature are not always fully consistent. These contradictory results can sometimes be explained by field measurements under different climatic conditions, different features of landscapes, air deposition rates on ground surfaces, and groundwater flow interactions with surface water. Integrated modelling has been suggested to overcome these inconsistencies. Physical‐based and empirical models are the most popular approaches for LU‐SWQ studies. Generally, anthropogenic LU such as agricultural and urban areas usually enhances nutrient concentrations much more than natural lands such as forest and barren. Developing sustainable metropolitan areas instead of rural areas, establishing high‐standard wastewater treatment plants, and practicing efficient fertiliser application would ameliorate the poor nutrient conditions in SWQ. Riparian vegetation, grassed swales, and construction of artificial wetlands as buffer zones are the most promising natural water quality control measures. 相似文献
114.
Abdullah H. A. Dehwah Samir Al‐Mashharawi Kim Choon Ng Thomas M. Missimer 《Ground water》2017,55(3):316-326
An investigation of a sea water reverse osmosis desalination facility located in western Saudi Arabia has shown that aquifer treatment of the raw sea water provides a high degree of removal of natural organic matter (NOM) that causes membrane biofouling. The aquifer is a carbonate system that has a good hydraulic connection to the sea and 14 wells are used to induce sea water movement 400 to 450 m from the sea to the wells. During aquifer transport virtually all of the algae, over 90% of the bacteria, over 90% of the biopolymer fraction of NOM, and high percentages of the humic substance, building blocks, and some of the low molecular weight fractions of NOM are removed. Between 44 and over 90% of the transparent exopolymer particles (TEP) are removed with a corresponding significant reduction in concentration of the colloidal fraction of TEP. The removal rate for TEP appears to be greater in carbonate aquifers compared to siliciclastic systems. Although the production wells range in age from 4 months to 14 years, no significant difference in the degree of water treatment provided by the aquifer was found. 相似文献
115.
The seismicity of the northeastern part of the Indian Ocean in connection with the general structural peculiarities of the
main tectonic structures of the bottom is presented. The three main ranges of higher seismic activity at the depths of 0–17,
20–27, and 32–35 km divided by aseismic layers are revealed. The seismic activity at depths of more than 35 km is almost not
detected both for the ocean and for the Indian peninsula. The nature of the distribution of the seismicity as such in the
lithosphere is discussed. Using the results of anomalous au]gravitational field transformations, the prolongation of the East
Indian Ridge structure is revealed to 19 degrees north, while the relationship of the Afanasy Nikitin Rise and the 85th Degree
Ridge is not reflected at the tranforms. In the Cocos Basin, the mutually perpendicular disturbance zones of northeastern
and northwestern strike, as well as the point of their crossing, where the maximal number of earthquake foci are concentrated,
are distinguished. A conclusion concerning the substantial disturbance of the strength properties of the lithosphere in this
zone as a consequence of the geodynamical processes, which are accompanied by fracture tectonics, is reached. 相似文献
116.
Field examples of fault-related folds were observed in the south-western margin of the Sirt basin, south-central Libya. Single or paired (conjugate) monoclines, drape synclines, special drag faults can be put in a geometric and evolutionary model, which describes the propagation of basement faults to overlying sediments. At the first stage of evolution the propagating normal or oblique-slip faults show segmentation along-dip direction. Fault segments are separated by continuous, moderately to strongly bended horizons, which show different degrees of diagenesis than surrounding intervals. Fault-related folding and faulting was coeval with lithification of certain carbonate levels. Their gradual cementation increased the rigidity of layers promoting discrete faulting and breaching of fault-related folds. However, folding can be maintained up to the extent when layer dip approaches the dip of the propagating fault zone. This type of deformation can be characteristic for sequences consisted of lithified carbonates sandwiched between thicker marl/shale intervals. 相似文献
117.
Role of fluvial and structural processes in the formation of the Wahiba Sands, Oman: A remote sensing perspective 总被引:1,自引:0,他引:1
C.A. Robinson F. El-Baz T.M. Kusky M. Mainguet F. Dumay Z. Al Suleimani A. Al Marjeby 《Journal of Arid Environments》2007,69(4):676-694
The Wahiba Sands in northeastern Oman are bordered on the north, south and west by highlands. Remote sensing data are used to characterize the region between 19–23.5°N and 56.5–60°E by mapping surface and near-surface drainage, faults and fractures and aeolian features. It is suggested that the sands were originally deposited with surface runoff from the principal wadis and fluvially reworked fault zones, which define the northeastern and southwestern margins. These fluvial processes resulted in the accumulation of the vast groundwater resources now stored there. During dry climates, wind became the principal modification regime and it began to sort and shape the sediments into the dune forms that characterize today's Wahiba region. The thickness of the sands reflects the depth of the basin in which they lie. The center of the basin is filled with the thickest sand (the High Sands) and contains the highest groundwater concentrations. Presently, aeolian reworking dominates in the Wahiba region, although the Low and the Peripheral Sands continue to experience some fluvial action from occasional, seasonal rainfall. Even though dry conditions dominate today, it is clear that similar to the Sahara of North Africa, the surface sands of the Wahiba basin are indicators of groundwater occurrence. 相似文献
118.
119.
120.
Rebecca E. Eager Sethu Raman Teddy R. Holt Douglas Westphal Jeffrey Reid Jason Nachamkin Ming Liu Abdulla Al Mandoos 《Pure and Applied Geophysics》2007,164(8-9):1747-1764
A statistical evaluation of the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS®) was performed over the Arabian Gulf region for the period, 1 August to 5 October, 2004. Verification skill scores of bias and root-mean-square error were estimated for surface variables and for vertical profiles to investigate any diurnal variations. The model predictions of boundary-layer heights are compared with the observations at Abu Dhabi, United Arab Emirates. The Middle East presents challenges to numerical weather prediction due to complex land-ocean-land mesoscale processes. An independent data set of surface measurements from 50 stations in the UAE was available from the Department of Water Resources Studies, Abu Dhabi for model verification. The results indicate a diurnal variation in the model errors. The errors are small considering the magnitudes of the observed variables. Errors in the coastal region can be attributed to the differences in the timing of the onset of sea and land breeze circulations in the simulations as compared to the observations. Errors are relatively smaller in the offshore locations. 相似文献