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111.
The discovery of Kef en-Naga site, an open-air human occupation in northeastern Algeria, was favored by a sandstone quarrying where work truncated much of the archaeological sequence on its cross-section. A multidisciplinary rescue excavation conducted on this site provided, for the first time in the region, the evidence of superimposition of two stratigraphic levels (lower and upper) of sandy clay deposits formed in humid paleoenvironmental conditions. Besides, XRD analysis show that a large amount of hematite (Fe2O3) is localized at the lower level of the stratigraphic section, where iron is found in oxide form due to the moisture. As for rock magnetic property characterization analysis, the various magnetic parameters have strong values in the upper level, and the grains are small-sized. However, various magnetic parameters are lower at the lower level and the magnetic grain concentration is reduced. Although the site is lacking faunal and carpological remains, thereby depriving us of reliable dates, the two stratigraphic levels are correlated to the Holocene according to archaeological and paleoenvironmental considerations. The lower level likely corresponding to an early Epipaleolithic culture marked by the production of microliths using a microburin blow technique, while the upper level is related to a subsequent Epipaleolithic phase, characterized by the disappearance of microburin blow technique, the dominance of an industry on flakes and the existence of pressure debitage.  相似文献   
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The Ubaid cultural phenomena (6500–4200 BC) of southern Mesopotamia has been used to characterise other archaeological sites in the Arabian Gulf region. The aim of this inquiry is to explore the nature of the interaction between the homeland of the Ubaid and the wider Gulf region. Through the use of a non-destructive portable X-ray fluorescence (pXRF) spectrometer, this study seeks to characterise and identify the chemical and mineralogical compositions of the ceramic assemblage from the Bahra 1 site of the As-Sabbiya region, Kuwait. The chemical results demonstrated that a combination of six trace elements [rubidium (Rb), strontium (Sr), yttrium (Y), zirconium (Zr), niobium (Nb) and barium (Ba)] occur significantly enough to delineate clay-based artifact groups—local red coarse from Ubaid, while the mineralogical analysis confirms the pXRF result and identifies the source of the raw materials and temper as well. Also, the comparison between the Ubaid and Bronze Age assemblage results suggests that potters used different clay resources within their own regions and/or production techniques.  相似文献   
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Roger Keil  Harris Ali 《对极》2007,39(5):846-873
Abstract: Based on a case study of the 2003 severe acute respiratory syndrome (SARS) outbreak in Toronto, Canada, this article suggests that we may have to rethink our common perception of what urban governance entails. Rather than operating solely in the conceptual proximity of social cohesion and economic competitiveness, urban governance may soon prove to be more centrally concerned with questions of widespread disease, life and death and the construction of new internal boundaries and regulations just at the time that globalization seems to suggest the breakdown of some traditional scalar incisions such as national boundaries in a post‐Westphalian environment. We argue that urban governance must face the new (or reemerging) challenge of dealing with infectious disease in the context of the “new normal” and that global health governance may be better off by taking the possibilities that rest in metropolitan governance more seriously.  相似文献   
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The prejudicial linking of infection with ethnic minority status has a long-established history, but in some ways this association may have intensified under the contemporary circumstances of the "new public health" and globalization. This study analyzes this conflation of ethnicity and disease victimization by considering the stigmatization process that occurred during the 2003 outbreak of Severe Acute Respiratory Syndrome (SARS) in Toronto. The attribution of stigma during the SARS outbreak occurred in multiple and overlapping ways informed by: (i) the depiction of images of individuals donning respiratory masks; (ii) employment status in the health sector; and (iii) Asian-Canadian and Chinese-Canadian ethnicity. In turn, stigmatization during the SARS crisis facilitated a moral panic of sorts in which racism at a cultural level was expressed and rationalized on the basis of a rhetoric of the new public health and anti-globalization sentiments. With the former, an emphasis on individualized self-protection, in the health sense, justified the generalized avoidance of those stigmatized. In relation to the latter, in the post-9/11 era, avoidance of the stigmatized other was legitimized on the basis of perceiving the SARS threat as a consequence of the mixing of different people predicated by economic and cultural globalization.  相似文献   
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Strength hierarchy assessment is a method that can be utilized to identify the weakest structural element at a reinforced concrete (RC) beam-column joint. The method was extensively used in various research activities at the University of Canterbury, which mainly involved beam-column joint subassembly tests. However, this method required improvements and refinements in order to be adopted in multi-story building applications. In this paper, the improvements made to the method are reported. In the improved method, capacity of the weakest element at every beam-column joint in an RC frame building can be related to the corresponding global base shear demand. The method has been illustrated via two example applications: an RC frame lacking joint shear reinforcement and a modern RC frame with adequate joint shear reinforcement. The case study examples confirmed the accuracy and the effectiveness of the method.  相似文献   
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Abstract

Monitoring and understanding of land use/forest cover dynamics as well as the factors affecting the changes in land use/forest cover are necessary for the sustainable management of natural resources. This study analyzes the spatial and temporal changes in land use and forest cover patterns in a typical mountain forest area in the Torul State Forest Enterprise area of Northeastern Turkey. The investigation evaluates the temporal changes of the spatial structure of forest conditions through the spatial analysis of forest-cover type maps from 1984 and 2005 using GIS and FRAGSTATS. The evidence presented here showed that there were drastic changes in the temporal and spatial dynamics of land use/forest cover, and between 1984 and 2005 there was a net increase of 19.9% in total forested area. Productive forest area increased by 3161 ha, although degraded forest area increased 9216 ha. In examining the changes of crown closure and development stages of the forest ecosystem during the study period, the forest stand area with low crown closures increased. The regenerated area increased because of regeneration activities while the other development stages were left to grow to older development stages in the period. These results regarding the crown closure and development stage show that forest quality has increased, and this is partly due to emigration of the rural population in Torul. In terms of spatial configuration, the landscape structure in Torul, the State Forest Enterprise area, changed substantially over the 21-year study period, resulting in fragmentation of the landscape as indicated by large patch numbers and smaller mean patch sizes, owing to heavy timber subtraction, illegal cutting, and uncontrolled stand treatments.  相似文献   
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