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121.
This article explores the causes for differences in the average CO2 emissions intensity of the new passenger car (NPC) fleet in member states (MS) across Europe. Although EU policies mitigating CO2 emissions from NPCs have been in place since 1999, MS strongly diverge in the absolute amount and relative change in emissions over the last decade. The authors employ a qualitative approach to analyse the factors, in particular national vehicle taxes, contributing to this divergence and the relative contribution of national and European policies in reducing national CO2 emissions from NPCs. The analysis shows that there has been a significant reduction in CO2 emissions intensity of NPCs since 2007 across most MS, compared with the six years previous to that date. This would indicate that EU-wide policies, such as the CO2 vehicles regulation, along with the economic recession in 2008, have influenced national NPC CO2 emissions. Generally, countries with CO2-differentiated vehicle taxes are observed as more likely to have achieved greater reductions in CO2 emissions. However, over the same period there have been many confounding factors, such as economic instability in the EU, that also influence NPC emissions. Using more detailed case study analyses of six countries, the authors find that there is scope for well-designed national vehicle tax policies to drive NPC emissions down further than the EU average. In countries with the highest success rate, such as the Netherlands, the design of the vehicle tax, as part of a well-aligned policy package, has been very important in delivering the biggest reductions in CO2 emissions from NPCs.

POLICY RELEVANCE

The transport sector continues to be an intractable source of CO2 emissions. Governments around the world are seeking effective policies to deal with the increase in passenger car CO2 emissions appropriate to their own circumstances. This article examines the experience of EU MS with CO2-differentiated vehicle taxes in reducing CO2 emissions in the context of other national and international contributing factors. It should therefore both be useful to policy makers and contribute to climate policy research in general.  相似文献   

122.
Heavy snowfalls can pose natural hazards in the North American Great Lakes region. Maximum annual snowfalls are presented from an extensive data base at 82 long-period-of-record stations. In the absence of site-specific information, these data should be useful to designers, planners, and resource managers in the region. A relationship exists between maximum snowfalls and latitude because the northern Great Lakes climate is cooler and drier than the climate of the southern Great Lakes. A relationship between longitude and maximum snowfalls appears to be based on the longitudinal variation of precipitable water vapor aloft. No apparent relationship exists between maximum snowfall and elevation when station data are analyzed without regard to data from lake-effect zones. However, when one lake-effect region was analyzed in detail, an orographic effect was clearly evident in both maximum and average annual snowfalls.  相似文献   
123.
Analysis of 24 reference materials for B, Sm, Gd, H, has been carried out over several years, using prompt gamma neutron activation analysis. The results are compared with values obtained by other workers, in order to better calibrate these standards. In most cases our results of repeated analysis of RMs show agreement with results from other laboratories, using various methods. A djustments to working values are proposed in some cases.  相似文献   
124.
Lithology variation is known to have a major control on landslide kinematics, but this effect may remain unnoticed due to low spatial coverage during investigation. The large clayey Avignonet landslide (French Alps) has been widely studied for more than 35 years. Displacement measurements at 38 geodetic stations over the landslide showed that the slide surface velocity dramatically increases below an elevation of about 700 m and that the more active zones are located at the bottom and the south of the landslide. Most of the geotechnical investigation was carried out in the southern part of the landslide where housing development occurred on lacustrine clay layers. In this study, new electrical prospecting all across the unstable area revealed the unexpected presence of a thick resistive layer covering the more elevated area and overlying the laminated clays, which is interpreted as the lower part of moraine deposits. The downslope lithological boundary of this layer was found at around 700 m asl. This boundary coincides with the observed changes in slide velocity and in surface roughness values computed from a LiDAR DTM acquired in 2006. This thick permeable upper layer constitutes a water reservoir, which is likely to influence the hydromechanical mechanism of the landslide. The study suggests a major control of vertical lithological variations on the landslide kinematics, which is highlighted by the relation between slide velocity and electrical resistivity.  相似文献   
125.
Existing GIS‐based least‐cost routefinding approaches can in some cases be confounded by linear features in the landscape whose crossing costs are high relative to other traversing costs found throughout the landscape. Unfortunately, such high‐cost linear features are not uncommon; they frequently occur in the form of hydrologic features whose crossing costs are high relative to costs of traversing the surrounding dry land. This study (1) enumerates the situations where existing approaches can fail, (2) proposes a simple method for overcoming the limitations of the existing approaches, and (3) conducts an experiment to assess the impact of the weaknesses of existing approaches and the magnitude of the differences between the results produced by existing and revised approaches. Our results show that in mountainous terrain, linear hydrologic features with high crossing costs can have a profound impact on least‐cost routes, and the choice of solution method has equally profound impacts on the optimal route produced by the analysis.  相似文献   
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128.
Mass-balance models have been constructed using inverse methodology for the northern Gulf of St. Lawrence for the mid-1980s, the mid-1990s, and the early 2000s to describe ecosystem structure, trophic group interactions, and the effects of fishing and predation on the ecosystem for each time period. Our analyses indicate that the ecosystem structure shifted dramatically from one previously dominated by demersal (cod, redfish) and small-bodied forage (e.g., capelin, mackerel, herring, shrimp) species to one now dominated by small-bodied forage species. Overfishing removed a functional group in the late 1980s, large piscivorous fish (primarily cod and redfish), which has not recovered 14 years after the cessation of heavy fishing. This has left only marine mammals as top predators during the mid-1990s, and marine mammals and small Greenland halibut during the early 2000s. Predation by marine mammals on fish increased from the mid-1980s to the early 2000s while predation by large fish on fish decreased. Capelin and shrimp, the main prey in each period, showed an increase in biomass over the three periods. A switch in the main predators of capelin from cod to marine mammals occurred, while Greenland halibut progressively replaced cod as shrimp predators. Overfishing influenced community structure directly through preferential removal of larger-bodied fishes and indirectly through predation release because larger-bodied fishes exerted top-down control upon other community species or competed with other species for the same prey. Our modelling estimates showed that a change in predation structure or flows at the top of the trophic system led to changes in predation at all lower trophic levels in the northern Gulf of St. Lawrence. These changes represent a case of fishery-induced regime shift.  相似文献   
129.
The multivariate variogram and the multivariate covariogram are used as spatial weighting functions for forming spatially homogeneous groups automatically. The groups are created after either deflating similarities between distant samples with the multivariate covariogram or by inflating dissimilarities between distant samples with the multivariate variogram. These approaches can be seen as generalization of the Oliver and Webster proposal. Two data sets show the efficiency of the two weighting functions when compared to the classical approach which does not take spatial information into account. In one case study, the weighting of similarities by the multivariate covariogram showed more interpretable results than the weighting of dissimilarities by the multivariate variogram.  相似文献   
130.
We investigate the accuracy to which we can retrieve the solar photospheric magnetic field vector using the Helioseismic and Magnetic Imager (HMI) that will fly onboard of the Solar Dynamics Observatory by inverting simulated HMI profiles. The simulated profiles realistically take into account the effects of the photon noise, limited spectral resolution, instrumental polarization modulation, solar p modes, and temporal averaging. The accuracy of the determination of the magnetic field vector is studied by considering the different operational modes of the instrument.  相似文献   
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