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991.
Ecological modernization theory posits that social movements play a central role in the environmental transformation of contemporary society. How they do so has received limited scholarly attention. This article seeks to reduce this thesis to a number of propositions which are then examined in light of the experience of the pulp and paper industry in the 1980s and 1990s. Drawing on field research and interviews in Southeast Asia, Australia and the United States, as well as available data, the study finds that social movements were instrumental in the environmental transformation of the pulp industry, with important differences between North and South. It concludes with a call for more nuanced studies of the influence of social movements on different sectors and countries, especially in newly industrializing countries where more tenuous and dependent forms of ecological modernization may be emerging.  相似文献   
992.
Recent work has celebrated the political potential of ‘counter‐mapping’, that is, mapping against dominant power structures, to further seemingly progressive goals. This article briefly reviews the counter‐mapping literature, and compares four counter‐mapping projects from Maasai areas in Tanzania to explore some potential pitfalls in such efforts. The cases, which involve community‐based initiatives led by a church‐based NGO, ecotourism companies, the Tanzanian National Parks Authority, and grassroots pastoralist rights advocacy groups, illustrate the broad range of activities grouped under the heading of counter‐mapping. They also present a series of political dilemmas that are typical of many counter‐mapping efforts: conflicts inherent in conservation efforts involving territorialization, privatization, integration and indigenization; problems associated with the theory and practice of ‘community‐level’ political engagement; the need to combine mapping efforts with broader legal and political strategies; and critical questions involving the agency of ‘external’ actors such as conservation and development donors, the state and private business interests.  相似文献   
993.
994.
The analysis by nuclear activation techniques and by inductively coupled plasma mass spectrometry combined with an UV laser of a large number of gold coins issued in the Arab Empire from the seventh to the 12th century ad showed that several different supplying sources were used, according to the region and to the period. The aim of this paper is to point out the circulation of gold in the Near and Middle Eastern mints of the Arab Empire and to make a parallel with the mints’ policies running in the other regions of the Empire, such as North Africa, the Iberian Peninsula and the Sicily. The identification of different gold ores by means of characteristic trace elements indicated recycling of the ancient coinage and, after ad 750, the minting in the entire Arab Empire of different new gold ores: Egyptian type, North Eastern type and West African type. The analysis of a small number of silver coins from the same periods and regions also showed a change in the ore supply after ad 750.  相似文献   
995.
张国焘关于中共成立前后情况的讲稿   总被引:6,自引:0,他引:6  
不久前,俄罗斯科学院远东研究所K·B·舍维廖夫教授给本刊寄来了新发现的两份珍贵档案材料:张国焘关于中共成立情况的两次讲课稿.据舍维廖夫先生称,讲稿写在1929年印制的笔记本上,估计是在以瞿秋白为首的中共党史教研室成立后为莫斯科中山大学撰写的.由于张国焘是中国共产党的早期领导人之一,参加了中共一大及中共创立前后的许多重要活动,因此他早年撰写的这两份讲稿,无疑具有重要的资料价值.我们特予刊登,以飨读者.  相似文献   
996.
Books reviewed in this article:
Ernest Freeberg, The Education of Laura Bridgman: The First Deaf and Blind Person to Learn Language
Elisabeth Gitter, The Imprisoned Guest: Samuel Howe and Laura Bridgman, the Original Deaf–Blind Girl  相似文献   
997.
Gas breakthrough experiments on fine-grained sedimentary rocks   总被引:1,自引:0,他引:1  
The capillary sealing efficiency of fine‐grained sedimentary rocks has been investigated by gas breakthrough experiments on fully water saturated claystones and siltstones (Boom Clay from Belgium, Opalinus Clay from Switzerland and Tertiary mudstone from offshore Norway) of different lithological compositions. Sand contents of the samples were consistently below 12%, major clay minerals were illite and smectite. Porosities determined by mercury injection lay between 10 and 30% while specific surface areas determined by nitrogen adsorption (BET method) ranged from 20 to 48 m2 g ? 1. Total organic carbon contents were below 2%. Prior to the gas breakthrough experiments the absolute (single phase) permeability (kabs) of the samples was determined by steady state flow tests with water or NaCl brine. The kabs values ranged between 3 and 550 nDarcy (3 × 10?21 and 5.5 × 10?19 m2). The maximum effective permeability to the gas‐phase (keff) measured after gas breakthrough on initially water‐saturated samples extended from 0.01 nDarcy (1 × 10?23 m2) up to 1100 nDarcy (1.1 × 10?18 m2). The residual differential pressures after re‐imbibition of the water phase, referred to as the ‘minimum capillary displacement pressures’ (Pd), ranged from 0.06 to 6.7 MPa. During the re‐imbibition process the effective permeability to the gas phase decreases with decreasing differential pressure. The recorded permeability/pressure data were used to derive the pore size distribution (mostly between 8 and 60 nm) and the transport porosity of the conducting pore system (10‐5–10‐2%). Correlations could be established between (i) absolute permeability coefficients and the maximum effective permeability coefficients and (ii) effective or absolute permeability coefficients and capillary sealing efficiency. No correlation was found between the capillary displacement pressures determined from gas breakthrough experiments and those derived theoretically by mercury injection.  相似文献   
998.
Underwater gas and liquid escape from the seafloor has long been treated as a mere curiosity. It was only after the advent of the side‐scan sonar and the subsequent discovery of pockmarks that the scale of fluid escape and the moon‐like terrain on parts of the ocean floor became generally known. Today, pockmarks ranging in size from the ‘unit pockmark’ (1–10 m wide, < 0.6 m deep) to the normal pockmark (10–700 m wide, up to 45 m deep) are known to occur in most seas, oceans, lakes and in many diverse geological settings. In addition to indicating areas of the seabed that are ‘hydraulically active’, pockmarks are known to occur on continental slopes with gas hydrates and in association with slides and slumps. However, possibly their potentially greatest significance is as an indicator of deep fluid pressure build‐up prior to earthquakes. Whereas only a few locations containing active (bubbling) pockmarks are known, those that become active a few days prior to major earthquakes may be important precursors that have been overlooked. Pockmark fields and individual pockmarks need to be instrumented with temperature and pressure sensors, and monitoring should continue over years. The scale of such research calls for a multinational project in several pockmark fields in various geological settings.  相似文献   
999.
We predict that portions of the New Jersey continental slope were unstable approximately 0.5 million years ago. This instability was caused by rapid sediment loading during a Pleistocene sea‐level lowstand and by flow focusing in underlying, permeable Miocene strata. The simulated instability is consistent with soft‐sediment deformation and small slumps in Pleistocene strata of the Hudson Apron. Stability of the New Jersey margin has increased since 0.3 Ma because sedimentation rate has decreased. Today, the modelled factor of safety (FS) for the upper slope is approximately 1.5 whereas in the lower slope it exceeds 3. We predict that sedimentation rate is a dominant factor on slope stability. When rapid and asymmetric loading of a highly permeable sedimentary layer occurs, the location of instability can shift seaward to regions where sedimentation rates are low. Stability calculations use pressures and effective stresses predicted by a coupled sedimentation‐fluid flow model. This hydrodynamic analysis demonstrates how the interplay of sedimentation and fluid migration affects the distribution, timing, and size of sedimentary failures.  相似文献   
1000.
The Devonian Antrim Shale is an organic‐rich, naturally fractured black shale in the Michigan Basin that serves as both a source and reservoir for natural gas. A well‐developed network of major, through‐going vertical fractures controls reservoir‐scale permeability in the Antrim Shale. Many fractures are open, but some are partially sealed by calcite cements that retain isotopic evidence of widespread microbial methanogenesis. Fracture filling calcite displays an unusually broad spectrum of δ13C values (+34 to ?41‰ PDB), suggesting that both aerobic and anaerobic bacterial processes were active in the reservoir. Calcites with high δ13C values (>+15‰) record cementation of fractures from dissolved inorganic carbon (DIC) generated during bacterial methanogenesis. Calcites with low δ13C values (13C values between ?10 and ?30‰ can be attributed to variable organic matter oxidation pathways, methane oxidation, and carbonate rock buffering. Identification of 13C‐rich calcite provides unambiguous evidence of biogenic methane generation and may be used to identify gas deposits in other sedimentary basins. It is likely that repeated glacial advances and retreats exposed the Antrim Shale at the basin margin, enhanced meteoric recharge into the shallow part of the fractured reservoir, and initiated multiple episodes of bacterial methanogenesis and methanotrophic activity that were recorded in fracture‐fill cements. The δ18O values in both formation waters and calcite cements increase with depth in the basin (?12 to ?4‰ SMOW, and +21 to +27‰ PDB, respectively). Most fracture‐fill cements from outcrop samples have δ13C values between ?41 and ?15‰ PDB. In contrast, most cement in cores have δ13C values between +15 and +34‰ PDB. Radiocarbon and 230Th dating of fracture‐fill calcite indicates that the calcite formed between 33 and 390 ka, well within the Pleistocene Epoch.  相似文献   
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