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991.
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   
992.
This mischievously artful essay plays out on several levels; think of them as storeys of an imaginary castle much like the real, solid, central Italian one it explores and expounds. On its own ground floor, the essay recounts a gruesome murder, a noble husband's midnight revenge upon his wife and upon her bastard lover, his own half–brother, in her castle chamber, in bed. In sex. Of course. The murder itself is pure Renaissance, quintessential Boccaccio or Bandello, but the aftermath, in fort and village, is more singular, more ethnographically delightful, as castle and village trace a ceremonious passage from frozen limbo to fluid grief and storytelling, finally set in motion by the arrival of the dead wife's brother. Meanwhile, one flight up, the essay retells my own investigation of the real castle's geometry, as I clambered through rooms, peered out windows, prowled the roof, and scanned blueprints seeking the places of the plotters' plots. In an expository attic, I lodge reflections on my teaching stratagems, as I led a first–year seminar into detection's crafts and exposition's ploys. All the while, on its rooftop, this essay dances among fantastical chimneys and turrets of high theory and literary practice, musing on the patent irony of artful artifice, which evokes both the irony and the pathos of scholars' cool histories about hot deeds and feelings. Art suggests we authors had best hide ourselves, unlike normal essayists, so as not to spoil the show. But, I posit, our self–effacement is so conspicuous that it proclaims our presence, as in fact it should, and, by so doing, trumpets the necessary tensions of our artifice and craft. Thus artfulness itself nicely both proclaims and celebrates the bittersweet frustrations of historians' and readers' quest for knowledge and, especially, for experience of a lost past.  相似文献   
993.
994.
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   
995.
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   
996.
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   
997.
This study analyzes the faunal assemblages corresponding to the Middle and Upper Paleolithic and the Early Epipaleolithic for the central Spanish Mediterranean Region dated from between 135,000 and 9,000 B.P. To interpret these data, we employ a zooarchaeological and paleoeconomic perspective. Human large and small game hunting systems are analyzed through the identification of the origins of faunal assemblages, bone breackage patterns, and prey selection patterns. Our study shows that hunting systems changed significantly through time, which may be related to the characteristics of the Mediterranean ecosystem and, above all, to cultural changes.  相似文献   
998.
999.
The characterization of a ceremonial bronze axe is described. The axe is assigned to the Santamarian culture of north‐west Argentina, c. 1000–1470 ad, and was selected to increase presently limited knowledge of prehistoric metallurgy in the Andean region of Argentina. The characterization methods used were electron probe microanalysis, gamma radiography, X‐ray diffraction, optical metallography and microhardness testing. The axe was well cast in a bivalve mould, with the only defects in the area of an ancient fracture. The analysis showed that it is made from a tin bronze with a, probably, accidental addition of lead. Arsenic was found as a surface contamination, probably deriving from arsenic in the water of the stream in which the axe was found. The axe shows that Santamarian craftsmen had the skill to decorate the axe in an artistic style with a strong local accent while providing a functional, annealed and cold‐worked cutting edge.  相似文献   
1000.
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