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211.
Gillian Rose 《Geoforum》2009,40(1):46-54
The paper begins with the recent interest in what Mbembe has called ‘necropolitics’: the politics of the distribution of life and death by modern sovereign states. The necropolitical works through the production of spatialities, visualities, and bodies that are classed, racialised and gendered in particular ways. The paper explores a series of such productions in its discussion of the British press coverage of the bombs that exploded on London’s public transport system on 7 July 2005, and in particular the photographs used by the newspapers. It argues that the newspapers pictured bodies as gendered and racialised, with the former fixed and visible much more clearly than the latter. It further argues that the newspapers differentiated between various bodies by assuming that a certain sort of care was deserved only by some of those involved in the bombings. Finally, the paper examines how the coverage worked to place the readers of the newspapers in a specific position in the necropolitical order of power as citizens who care only for certain people, and in a particular way. The paper concludes by considering the implications of that specific caring for contemporary necropolitics and its visualities and spatialities.  相似文献   
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With respect to atmospheric impact, the 1982 eruption of the El Chichón volcano in Mexico is one of the most significant volcanic events of this century. The presence in the stratosphere, during several years, of an unusally high amount of sulfuric acid aerosols produced by this eruption is thought to be responsible for severe windshield damages on high-flying commercial jets. This problem took epidemic proportions in 1983–1984 and the cost to commercial aviation companies is estimated at several tens of millions of U.S. dollars.  相似文献   
214.
Peritidal carbonates of the Lower Jurassic (Liassic) Gibraltar Limestone Formation, which form the main mass of the Rock of Gibraltar, are replaced by fine and medium crystalline dolomites. Replacement occurs as massive bedded or laminated dolomites in the lower 100 m of an ≈460‐m‐thick platform succession. The fine crystalline dolomite has δ18Ο values either similar to, or slightly higher than, those expected from Early Jurassic marine dolomite, and δ13C values together with 87Sr/86Sr ratios that overlap with sea‐water values for that time, indicating that the dolomitizing fluid was Early Jurassic sea water. Absence of massive evaporitic minerals and/or evaporite solution‐collapse breccias in these carbonate rocks indicates that the salinity of sea water during dolomitization was below that of gypsum precipitation. The occurrence of peritidal facies, a restricted microbiota and rare gypsum pseudomorphs are also consistent with penesaline conditions (salinity 72–199‰). The medium crystalline dolomite has some δ18Ο and δ13C values and 87Sr/86Sr ratios similar to those of Early Jurassic marine dolomites, which indicates that ambient sea water was again a likely dolomitizing fluid. However, the spread of δ18Ο, δ13C and 87Sr/86Sr values indicates that dolomitization occurred at slightly increased temperatures as a result of shallow (≈500 m) burial or that dolomitization was multistage. These data support the hypothesis that penesaline sea water can produce massive dolomitization in thick peritidal carbonates in the absence of evaporite precipitation. Taking earlier models into consideration, it appears that replacement dolomites can be produced by sea water or modified sea water with a wide range of salinities (normal, penesaline to hypersaline), provided that there is a driving mechanism for fluid migration. The Gibraltar dolomites confirm other reports of significant Early Jurassic dolomitization in the western Tethys carbonate platforms.  相似文献   
215.
The effects of climate change on drinking-waterborne cryptosporidiosis transmission in the United States are analyzed using an influence diagram representation of epidemic development. Results from a systematic qualitative analysis indicate that climate change will have little effect on cryptosporidiosis incidence if the United States continues to be wealthy and maintains its commitment to public health. The major impact will, instead, be the additional costs of adapting to new climate regimes in order to avoid drinking-waterborne disease risk. These costs, for the most part, will be from improved monitoring and treatment of drinking water. The consequences of disaster scenarios are also considered. These, too, suggest that climate change per se will be a poor predictor of waterborne cryptosporidiosis in countries with high standards of living. Rather, the risk of epidemics will depend on the interplay between population, public health investment, infrastructure maintenance, emergency planning/response capabilities, water-treatment technologies, drinking-water regulations, and climate.  相似文献   
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217.
We have extended the fallout areas for each of two members of tephra-set W, erupted from Mount St. Helens about 1500 ad, by several hundred kilometers beyond the limits mapped in 1975. We traced one member (We) east into Idaho, and the other (Wn) northeast into British Columbia. After using stratigraphic and petrographic observations to assign more than 100 tephra samples to set W, we found 26 of these, selected for chemical analysis, to be closely similar in content of Ca, Fe, and K in glass shards. But improved homogeneity was evident when the 26 sampling localities for tephra W were segregated geographically, east vs. northeast of the volcano. When Ca:Fe:K proportions were plotted on a ternary diagram, there was no overlap of the plotting areas for these two groups of tephra W samples. Without such data, tephra layers We and Wn are currently separable only from stratigraphic and geographic information. Partial glass analysis is also an aid, along with stratigraphic position and petrographic characteristics, in distinguishing tephra W from associated tephra layers. These include tephra layers T and Yn from Mount St. Helens, as well as older tephra layers from Mount Mazama and Glacier Peak.  相似文献   
218.
Reference samples of three prominent pumice units of Glacier Peak tephra collected east of the volcano within a distance of 100 km are similar petrographically to units described by earlier workers. Glass shards isolated from these samples were analyzed by electron microprobe to determine the content of Ca, Fe, and K. Resulting data, plus those published for two other references samples, provide a basis for attributing certain outlying tephra layers from 14 locations in eastern Washington, Idaho, Wyoming, and Montana to eruptions of Glacier Peak. Ten of the samples have properties of both Glacier Peak tephra and Mount St. Helens set J tephra, but proportions of Ca:Fe:K in glass shards indicate that 9 of the 10 outlying samples came from Glacier Peak, whereas one is assigned to Mount St. Helens set J. The remaining six outlying samples, all from southeastern Washington, contain cummingtonite phenocrysts and are chemically similar to some parts of Mount St. Helens tephra sets that are older than 12,000 BP.  相似文献   
219.
Plagioclases in the 1974 high-Al basalt from Fuego Volcano have δO18 values of +6.0 to +8.5 per mil. Meteoric water cannot have played a significant role in Fuego’s magma. Large, weakly zone clear phenocrysts had δO18 values in the accepted mantle range, while patchyzoned and oscillatory-zoned plagioclases inferred to have formed later and shallower levels have slightly heavier oxygen isotopic ratios.  相似文献   
220.
Data on copper reserves, recent discovery rates, and historical tonnage-grade relations indicate that the U.S. can be approximately self-sufficient in copper to the year 2000 by mining grades similar to those presently being mined, and given reasonable exploration efforts, the U.S. can supply its demand for about 100 years by mining inferred tonnages above 0.1% Cu. However, recent price trends and the increased cost of mining lower grade ore will increase the price of copper at a rate faster than the general inflation rate, and may lead to significant imports because of their cheaper price.Compilation of the discovery history for copper shows that the Hubbert Gaussian curve is not applicable to predict copper reserves, and may not be applicable for other commodities.A compilation of the value of base and precious metal deposits discovered since 1940, along with meager data on cost and manpower used in exploration, indicates very little decrease in exploration effectiveness over the 40-year interval, in contrast to oil and uranium. Collection of better data on expenditures for metallic mineral exploration is recommended.  相似文献   
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