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Stephen K. Wegren Frode Nilssen Christel Elvestad 《Eurasian Geography and Economics》2016,57(6):671-699
AbstractFood security has guided Russia’s food policy since 2010. The article examines the impact of food security policy on the food system. The Russian model of food security combines government intervention in the form of assistance for domestic production while simultaneously restricting market access. Food security does not appear to have a deleterious impact on the food system. We measure impact on four dimensions. Financial support for agriculture continues to increase in nominal rubles. In food production, the beef and dairy branches continue to lag, but increased grain production has made Russia a global leader in grain exports. Average per capita food consumption improved, although the poor consume much less, and the decline of the ruble affects the way Russians shop. The largest impact of food security has been on food trade. Food security policy has brought food to the forefront as an instrument of foreign policy. Food trade is politicized, witnessed by the food embargo against the West and food import bans against Turkey and Ukraine. 相似文献
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Elizabeth Hervey Stephen 《Asian Population Studies》2016,12(1):50-67
South Korea experienced below replacement fertility for the first time in 1983, which also marked the point from which fertility rates continued to decline over the next 20 years to reach a low of 1.2 in 2003. In spite of recent pronatalist policies, the fertility rate has remained near this level and has not increased appreciably. The reasons for sustained low fertility in South Korea are complex and solutions remain elusive. One option that has been suggested is reunification with North Korea, which could address the eventual decline in the population and mitigate the increasing proportion of the elderly. Although the conditions surrounding the German reunification experience were vastly different than what Korea will likely undergo, it is informative to look at Germany as a guide to the demographic parameters of reunification. Three projection models for 2015–2050 are presented; even the highest fertility models show that reunification will not be the answer to population restructuring already underway in South Korea as a result of sustained low fertility. 相似文献
108.
Medieval Shipwrecks from North Norway and their Contribution to Understanding Maritime Interaction and Trade
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Stephen Wickler 《International Journal of Nautical Archaeology》2016,45(1):59-76
This article presents the remains of three medieval ships from North Norway. The sites are clustered near the Arctic Circle, two from the islands of Husøy (Træna) and Lovund in the Helgeland region, and a potential third wreck from the small lake Fiskvågvatn in Saltdal. Available information from the wrecks is presented to provide a basis for assessing their cultural contexts and relevance to medieval maritime activities, the dried‐cod (stockfish) trade in particular. The circumstances surrounding their discovery and documentation also offer insights into the history of cultural heritage management and role of community engagement in northern Norwegian shipwreck archaeology. 相似文献
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Stephen Brain 《Cold War History》2016,16(4):443-462
This paper argues that the Cold War, for all its environmental costs, brought in its train a hidden benefit: the creation of an international ideological competition that made meaningful environmental agreements more likely. After reviewing the history of Soviet environmental initiatives, the paper discusses the rise of international environmental agreements and the abrupt decline after 1991. 相似文献
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Exploring the potential linkages between oil‐field brine reinjection,crystalline basement permeability,and triggered seismicity for the Dagger Draw Oil field,southeastern New Mexico,USA, using hydrologic modeling
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Y. Zhang S. S. Edel J. Pepin M. Person R. Broadhead J. P. Ortiz S. L. Bilek P. Mozley J. P. Evans 《Geofluids》2016,16(5):971-987
We used hydrologic models to explore the potential linkages between oil‐field brine reinjection and increases in earthquake frequency (up to Md 3.26) in southeastern New Mexico and to assess different injection management scenarios aimed at reducing the risk of triggered seismicity. Our analysis focuses on saline water reinjection into the basal Ellenburger Group beneath the Dagger Draw Oil field, Permian Basin. Increased seismic frequency (>Md 2) began in 2001, 5 years after peak injection, at an average depth of 11 km within the basement 15 km to the west of the reinjection wells. We considered several scenarios including assigning an effective or bulk permeability value to the crystalline basement, including a conductive fault zone surrounded by tighter crystalline basement rocks, and allowing permeability to decay with depth. We initially adopted a 7 m (0.07 MPa) head increase as the threshold for triggered seismicity. Only two scenarios produced excess heads of 7m five years after peak injection. In the first, a hydraulic diffusivity of 0.1 m2 s?1 was assigned to the crystalline basement. In the second, a hydraulic diffusivity of 0.3 m2 s?1 was assigned to a conductive fault zone. If we had considered a wider range of threshold excess heads to be between 1 and 60 m, then the range of acceptable hydraulic diffusivities would have increased (between 0.1–0.01 m2 s?1 and 1–0.1 m2 s?1 for the bulk and fault zone scenarios, respectively). A permeability–depth decay model would have also satisfied the 5‐year time lag criterion. We also tested several injection management scenarios including redistributing injection volumes between various wells and lowering the total volume of injected fluids. Scenarios that reduced computed excess heads by over 50% within the crystalline basement resulted from reducing the total volume of reinjected fluids by a factor of 2 or more. 相似文献