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31.
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A pattern of mainly NW-striking tectonic zones is described in the western part of the Northeastern European Platform.  相似文献   
33.
Immigrant–native segregation is present in the spaces in which individuals from different ethnic/racial groups practice their everyday lives; interact with others and develop their ethnic, social and spatial networks. The overwhelming majority of academic research on immigrant segregation has focused on the residential domain, thus largely overlooking other arenas of daily interaction. The present study contributes to the emerging literature on immigrant residential and workplace segregation by examining changes in patterns of residential and workplace segregation over time. We draw our data from the Stockholm metropolitan region, Sweden’s main port of entry for immigrants. The results suggest a close association between residential and workplace segregation. Immigrant groups that are more segregated at home are also more segregated in workplace neighborhoods. More importantly, we found that a changing segregation level in one domain tends to involve a similar trend in the other domain.  相似文献   
34.
The paleogeographic reconstruction for an early Badenian connection of the Vienna Basin and the Carpathian Foredeep in the Mikulov area (Mikulov Gate) based on paleontological (otoliths) and geological (regional geology, tectonics) data has been provided. The ecologically homogenous deep water associations of otoliths in the most NW tip of the Vienna Basin (Sedlec HJ-2 Borehole) links up bathymetrically with nearly adequate otolith assemblages in the southernmost Moravian part of the foredeep. Ten meso- and bathypelagic teleost species have been identified in the Vienna Basin for the first time. Geological analyses proved inversion processes of recurrent nature along old faults of the NW-SE direction in the Dyje (Thaya) Depression. In the early Badenian the Mikulov Gate resulted from the sagging block of the Waschberg Zone. This marine channel was relatively deep (> 200m, as indicated by otoliths) and in all probability flooded an entire front of the nappes in this area.  相似文献   
35.
The European part of Russia exhibits highly developed sulphate and carbonate karst. It mostly occurs within river valleys with relatively thin covering deposits. These conditions may induce karst collapses, which appear to be the main danger for civil and industrial buildings. Evolution of karst rocks includes several epochs of karst development, which causes complicated distribution of karst caves in karst rocks and, as the result, irregular distribution of karst caves on the surface. Karst hazards prediction is mostly reliable within the geotechnical system "Karst-Construction", using probability methods. This approach allows creating 3 types of antikarst protection (alternative design of construction arrangement on a plan, structural protection of a construction and plugging of karst caves beneath construction foundation) and selecting the optimum or the most effective version or their rational combination.  相似文献   
36.
The growth of Pelvetia canaliculata (L.) Dec. et Thur., Fucus spiralis L., Fucus vesiculosus L. and Fucus serratus L. is measured in various concentrations of copper (12–970 μg/litre) during a period of ten days. Significant reductions in growth were observed at 12 μg/litre of copper added for P. canaliculata and F. spiralis, at 25 μg/litre for F. serratus and at 50 μg/litre for F. vesiculosus. There is a linear relationship between the percentage reduction (z) in growth rate and the product of time (x) and concentration (y), giving the equation z = kx × xy. The constant k is specific and may be used as a measure of resistance capacity to copper exposure. When previous data on Ascophyllum nodosum (L.) Le Jolis are included the five large Fucoids in the intertidal area may be ranked as follows according to their resistance capacity: A. nodosum > F. vesiculosus > P. canaliculata ? F. spiralis > F. serratus.  相似文献   
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The baryte occurrences along N to NW striking faults in Carboniferous and Devonian strata of the Ruhr area and the Rheinisches Schiefergebirge (Western Germany) are related to still presently active chloridic, Ba-Sr bearing Na and Na-Ca solutions. These originated from deeper seated waters which have their origin in meteoric waters circulating in the fault systems, and in fossil waters from Ba-rich Ordovician strata. Experimental results of the solubility behaviour of BaSO4 and SrSO4 in water and in aqueous solutions can explain the Ba and Sr content of these recent and fossil brines. A theory of Ba-Sr mineralisation is presented for the Rheinisches Schiefergebirge which is believed to find general application in other regions.  相似文献   
39.
A calibration data set of 51 surface sediment samples from Lake Donggi Cona on the northeastern Tibetan Plateau was investigated to study the relationship between sub-fossil ostracod assemblages and water depth. Samples were collected over a depth range from 0.6 to 80 m. A total of 16 ostracod species was identified from the lake with about half of the species restricted to the Tibetan Plateau and its adjacent mountain ranges and poorly known in terms of ecological preferences, and the other half displaying a mainly Holarctic distribution. Living macrophytes and macroalgae were recorded in Lake Donggi Cona down to a depth of about 30 m, and bivalve (Pisidium cf. zugmayeri) and gastropod (Gyraulus, Radix) shells were found down to depths of 43 and 48 m, respectively. The ostracod-water-depth relationship was assessed by multivariate statistical analysis and ostracod-based transfer functions for water depth were constructed. Weighted averaging partial least squares (WA-PLS) regression provided the best model with a coefficient of determination r 2 of 0.91 between measured and ostracod-inferred water depth, a root mean square error of prediction of 8% and a maximum bias of 10.6% of the gradient length, as assessed by leave-one-out cross-validation. Our results show the potential of ostracods as palaeo-depth indicators in appropriate settings. However, transfer-function applications using fossil ostracod assemblages for palaeo-depth estimations require a thorough understanding of the palaeolimnological conditions of lakes and therefore detailed multi-proxy analysis to avoid misinterpretation of ostracod-based inferences.  相似文献   
40.
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