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931.
932.
Genetic Relationship between Natural Gas Dispersal Zone and Uranium Accumulation in the Northern Ordos Basin, China 下载免费PDF全文
The Ordos Basin is well-known for the coexistence of oil, natural gas, coal and uranium. However, there has been little research to discuss the genetic relationship between them. In this paper, a case study of the Zaohuohao area in Dongsheng, Inner Mongolia, China, is conducted to investigate the genetic relationship between the natural gas and the uranium accumulation. Fluid inclusion data from the uranium-bearing sandstone samples indicate that the fluid inclusions formed in a gas-water transition zone. Using the homogeneous temperatures of aqueous inclusions coeval with hydrocarbon-bearing inclusions, combined with the buried history and paleo-temperature data, the gas-water transition zone reached the area at about 110 Ma. On the basis of this, the contents of Uranium (U) and Total Organic Carbon (TOC) of the samples were analyzed, and there was no obvious relation between them. With regard to the available data from both publications and this study, it is found that the U mineralization has a spatiotemporal accordance with the gas-water dispersal zone. Thus, it is believed that the natural gas in the gas-water zone is an effective reducer to the U-bearing ground water abundant in oxygen, which is the main factor to U accumulation. This result can be used as the reference to the U mines predicting and prospecting. 相似文献
933.
冀东铁精矿的物化性能测试 总被引:1,自引:0,他引:1
对冀东铁精矿进行了系统的物化性能测试。结果表明,铁精矿粒度较粗、颗粒表面光滑、比表面积小、SiO2含量较高。结合矿相结构分析了冀东铁精矿成球性能比较差的原因。采用3%的优质膨润土作铁精矿球团的黏结剂,制得球团的性能能够满足生产要求。 相似文献
934.
935.
由于自然伽马能谱测井(NGS)的放射性元素U、Th、K的含量与粘土矿物有着密切的关系,所以可利用NGS定性或定量确定油气储层粘土矿物含量。阐述了自然伽马能谱测井资料在确定粘土矿物含量中的地质依据,建立了研究地层粘土矿物含量的计算模型。由研究油田的NGS测井资料计算并对比了粘土矿物的含量,最终得到很好的效果。 相似文献
936.
本研究建立了一个反映植被辐射传输和几何光学特性的混合模型,以模拟半干旱地区天然草地的多波段反射率值。该模型引入一个几何相似性参数,用以描述植株冠层的几何形状对叶/枝角分布、阴影地面比例、冠层和地面各光学分量、冠层反射率和总反射率的影响。模型模拟值与研究区3个不同退化程度羊草草地的实测值较为吻合,而且退化程度越轻的草地,模拟效果也越好。对于中度退化草地,在高度与冠幅之比(chw)不变的情况下,当45°≤太阳天顶角sza≤75°时,不同几何形状植株的总反射率之间无显著差异;当0°≤sza〈45°或75°〈sza≤90°时,锥体与球体和柱体植株的总反射率之间有较显著差异;而球体和柱体植株的总反射率之间始终无显著差异。当chw由小到大变化时,以上结论基本不变。 相似文献
937.
Antonino D’Andrea Salvatore Cafiso Antonio Condorelli 《Pure and Applied Geophysics》2005,162(4):767-782
The recent earthquakes in California and Japan have shown the fundamental role that the road infrastructure plays in emergencies. In fact, only the maintenance of a sufficient level of efficiency can help to quickly reach the affected areas and thus avoid further serious consequences. The necessity of guaranteeing the functionality of the transport network during seismic events therefore requires seismic risk planning extended also to the road infrastructures in order to support the management of post-earthquake emergencies. Analogously it is fundamentally important to have analysis instruments of the road system able to preventatively evaluate the effects of earthquakes in order to identify possible emergencies, therefore preparing a program of intervention to reduce seismic risk on road networks. This paper proposes a methodology for the evaluation of seismic risk of road infrastructures according to the following points:Study of seismic hazard of the site for the definition of a seismic scenario using attenuation models in relation to historical seismology and the geological and tectonic characteristics of the territory;Analysis of the direct exposure connected to the probability of the presence of road users on the different parts of the network directly exposed to the seismic event;Analysis of the indirect exposure relative to the distribution of the population and the infrastructures for which post-earthquake accessibility must be guaranteed;Evaluation of the functional vulnerability in relation to the potential replaceability of damaged stretches considering network configuration and geometrical characteristics;Evaluation of structural vulnerability of the stretch correlated to the characteristics (structural, mechanical, technological, etc.) of the different components (bridges, embankments, trenches, tunnels) that make up the stretches obtained by the use of correctly elaborated tables for each component.The determination of global risk indexes of the single stretches and of the network, evaluated by means of a relationship between the ascertained parameters derived from the investigation of the previous points, provides the necessary information for the definition of mitigation measures to reduce the risk and for management planning before and after disaster. The proposed methodology, which has already been applied to a restricted area, is currently being applied to the province of Catania (Sicily, Italy), which is one of the geographical regions of highest seismic risk in Europe, and its future extension to all of eastern Sicily is foreseeable. 相似文献
938.
LIU Xiangwen JIN Zhenmin QU Jing & WANG Lu . State Key Laboratory of Geological Processes Mineral Resources China University of Geosciences Wuhan China . Graduate School of China University of Geosciences Wuhan China . Faculty of Earth Sciences China University of Geosciences Wuhan China 《中国科学D辑(英文版)》2005,48(9):1368-1376
Since coesite-bearing eclogite was found in the Dabie-Sulu area[1-3], the ultrahigh-pressure (UHP) me- tamorphic belt has become a hot topic studying by domestic and overseas scientists. The studying about the forming depth of UHP metamorphic rocks is ex- tremely important, because the peak-metamorphic depth of UHP metamorphic rocks exhumated back to the crust is the key to discuss the processes of magma formation, fluid activity and metamorphism at bottom of orogenic belt. The discovery o… 相似文献
939.
漠滨金矿的可见金中,有一种呈聚集式乳滴状结构的自然金集合体。本文就其形成机理进行了探讨。这种结构显示的自然金的运动趋势和历史,为原生粗粒金的形成提供了一种可以探讨的途径。 相似文献
940.
Ethanol Production Using Corn,Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower 总被引:23,自引:0,他引:23
Energy outputs from ethanol produced using corn, switchgrass, and wood biomass were each less than the respective fossil energy inputs. The same was true for producing biodiesel using soybeans and sunflower, however, the energy cost for producing soybean biodiesel was only slightly negative compared with ethanol production. Findings in terms of energy outputs compared with the energy inputs were: • Ethanol production using corn grain required 29% more fossil energy than the ethanol fuel produced. • Ethanol production using switchgrass required 50% more fossil energy than the ethanol fuel produced. • Ethanol production using wood biomass required 57% more fossil energy than the ethanol fuel produced. • Biodiesel production using soybean required 27% more fossil energy than the biodiesel fuel produced (Note, the energy yield from soy oil per hectare is far lower than the ethanol yield from corn). • Biodiesel production using sunflower required 118% more fossil energy than the biodiesel fuel produced. 相似文献