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991.
992.
M. ALTAF ARAIN ROSE BLAIR† NORM FINKELSTEIN‡ JEFF BROOK§ MICHAEL JERRETT¶ 《The Canadian geographer》2009,53(2):165-190
The spatial and temporal variability of nitrogen dioxide (NO2 ) concentrations and their relationships with meteorology was evaluated in the Toronto–Hamilton urban airshed. NO2 concentrations were highest in the early morning and late evening. Mean concentrations were highest in winter, although individual one-hour NO2 concentrations were found to be highest in summer. Wind direction was the strongest control on hourly NO2 concentration, and temperature and wind speed also had an effect. Our analysis of NO2 concentration variation by wind direction showed that areas downwind of major highways, urban centres and industry were exposed to higher pollutant concentrations. Seasonal patterns of NO2 concentration displayed significant spatial heterogeneity, in particular, in Toronto. Onshore winds sheltered coastal inhabitants from the full extent of NO2 exposure they would otherwise experience. Seasonal variations in meteorology and emissions mean that the degree of spatial variability in NO2 concentrations changes from season to season. This study will help to improve existing land-use regression-based NO2 prediction models by incorporating meteorological controls on NO2 distributions for health effect studies. 相似文献
993.
A. Stewart Fotheringham 《Geographical analysis》2009,41(4):398-403
This article examines the relationship between spatial dependency and spatial heterogeneity, two properties unique to spatial data. The property of spatial dependence has led to a large body of research into spatial autocorrelation and also, largely independently, into geostatistics. The property of spatial heterogeneity has led to a growing awareness of the limitation of global statistics and the value of local statistics and local statistical models. The article concludes with a discussion of how the two properties can be accommodated within the same modelling framework. 相似文献
994.
Tor A. Benjaminsen Faustin P. Maganga Jumanne Moshi Abdallah 《Development and change》2009,40(3):423-445
Farmer–herder conflicts in Africa are often presented as being driven by ‘environmental scarcity’. Political ecologists, however, argue that these conflicts should be analysed within a broader historical and policy context. This article presents a case study of a local conflict in the Kilosa District in Tanzania that tragically culminated in the killing of thirty‐eight farmers on 8 December 2000. To understand the conflict, the authors argue that it is necessary to study the history of villagization and land use in the District, as well as national land tenure and pastoral policies. Attempts at agricultural modernization have fostered an anti‐pastoral environment in Tanzania. The government aim is to confine livestock keeping to ‘pastoral villages’, but these villages lack sufficient pastures and water supplies, leading herders to search for such resources elsewhere. Pastoral access to wetlands is decreasing due to expansion of cultivated areas and the promotion of agriculture. The main tool that pastoralists still possess to counteract this trend is their ability to bribe officials. But corruption further undermines people's trust in authorities and in the willingness of these authorities to prevent conflicts. This leads actors to try to solve problems through other means, notably violence. 相似文献
995.
996.
Christian Meyer Guido Brandt Wolfgang Haak Robert A. Ganslmeier Harald Meller Kurt W. Alt 《Journal of Anthropological Archaeology》2009,28(4):412-423
The Corded Ware is one of the major archaeological traditions of Late Neolithic Europe. Its burial customs are characterized by single graves but multiple burials also occur. We present a detailed study of antemortem and perimortem trauma in a group of Corded Ware skeletons from four multiple graves and give the most probable interpretation of the site, based upon all available bioarchaeological evidence. The pattern of observed injuries in male, female, and subadult skeletons, including cranial trauma, arrow wounds, and fractures of the forearm and hands points towards a violent event that resulted in the death of all individuals, most probably a raid. In contrast to comparable Neolithic raid sites, there was no complete extermination of the local population and no use of mass graves. The burials have been arranged with care and detailed knowledge about biological kinship ties [Haak, W., Brandt, G., de Jong, H.N., Meyer, C., Ganslmeier, R., Heyd, V., Hawkesworth, C., Pike, A.W.G., Meller, H., Alt, K.W., 2008. Ancient DNA, strontium isotopes, and osteological analyses shed light on social and kinship organization of the Later Stone Age. Proceedings of the National Academy of Sciences of the United States of America 105, 18226–18231]. The combination of clear causes of death and the proven biological relationships among some of the individuals, including a nuclear family, provides new and important insights into Corded Ware mortuary customs and the reasons why and how multiple graves have been utilised. 相似文献
997.
Climatic deterioration in the later middle ages was associated with an increasing frequency of marine storm surges affecting the coasts of the southern North Sea. This paper investigates the impact of storm surges upon the lands bordering the Thames estuary and tidal river between the mid-thirteenth and mid-fifteenth centuries. Land use in the coastal and riverine marshes is reviewed, and the means and costs of defence against marine flooding explored. The impact of flooding upon human use of the marshlands, upon the suburbs of medieval London and upon the Thames fisheries are all investigated. Stress is placed upon the complex interaction of economic and environmental factors in determining the response to the threat of marine flooding. 相似文献
998.
The origins of raw glass used to fashion Mycenaean beads were explored using trace elements analyzed by laser ablation ICP-TOFMS. The use of this minimally destructive technique for the in-situ analysis of these beads was ideal given that the material is exceedingly rare and thus too sensitive to make use of traditional micro-sampling (e.g., by scalpel). A wide range of trace elements were measured to compare these Greek glasses to other Late Bronze Age glass coming from Egypt and Mesopotamia. Of the eleven beads analyzed, four blue glasses colored with cobalt and two blue/green glasses colored with copper have trace element compositions consistent with an Egyptian origin of manufacture. The other five of the glasses, all colored with copper, were found to conform to the composition of Mesopotamian glass. These data are the first to demonstrate direct and clear evidence for the trade of raw glass to the Mycenaean states. 相似文献
999.
Stable carbon- and nitrogen-isotope ratios were measured for segments along the shafts of hair from eight individuals from the site of Pacatnamu, located in the Jequetepeque Valley on the north coast of Peru. All are from known grave contexts dating from Moche (ca. 450–750 A.D.) to Lambayeque periods (ca. 900–1100 A.D.). The mean δ13C and δ15N values of hair segments from individuals are comparable to those of bone, and demonstrate increased consumption of marine resources in the Lambayeque times relative to the Moche period. 相似文献
1000.
Gary A. King M. Thomas P. Gilbert Eske Willerslev Matthew J. Collins Harry Kenward 《Journal of archaeological science》2009
We report the recovery of short fragments of PCR amplifiable ancient DNA from exoskeletal fragments of the grain weevil Sitophilus granarius (L.) extracted from Roman and medieval deposits in Northern England. If DNA preservation in archaeological insect remains is widespread then many applications in the spheres of evolutionary studies and archaeology can be conceived, some of which are outlined. 相似文献