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Lithium (Li) concentrations of produced water from unconventional (horizontally drilled and hydraulically fractured shale) and conventional gas wells in Devonian reservoirs in the Appalachian Plateau region of western Pennsylvania range from 0.6 to 17 mmol kg?1, and Li isotope ratios, expressed as in δ7Li, range from +8.2 to +15‰. Li concentrations are as high as 40 mmol kg?1 in produced waters from Plio‐Pleistocene through Jurassic‐aged reservoirs in the Gulf Coast Sedimentary Basin analyzed for this study, and δ7Li values range from about +4.2 to +16.6‰. Because of charge‐balance constraints and rock buffering, Li concentrations in saline waters from sedimentary basins throughout the world (including this study) are generally positively correlated with chloride (Cl), the dominant anion in these fluids. Li concentrations also vary with depth, although the extent of depth dependence differs among sedimentary basins. In general, Li concentrations are higher than expected from seawater or evaporation of seawater and therefore require water–mineral reactions that remove lithium from the minerals. Li isotope ratios in these produced waters vary inversely with temperature. However, calculations of temperature‐dependent fractionation of δ7Li between average shale δ7Li (?0.7‰) and water result in δ7Liwater that is more positive than that of most produced waters. This suggests that aqueous δ7Li may reflect transport of water from depth and/or reaction with rocks having δ7Li lighter than average shale.  相似文献   
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Mobility is a powerful resource young people can draw on to improve their lives, but it can also entail risks. This paper explores how mobility becomes a contradictory resource for peripatetic Qur'anic students (almajirai) in Kano State in northern Nigeria. Moving to urban areas allows the young almajirai to escape difficult conditions and to access educational and income opportunities absent in their rural homes. It makes it possible for them to adopt self-conceptions as migrants in search of sacred knowledge who were once widely respected. However, economic decline has made survival in the city more difficult. Lacking the economic and cultural resources to participate in displays of status, and without social superiors to speak for them, the almajirai feel they have become fair game for those searching for scapegoats.  相似文献   
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In the 1940s, scholars across a variety of disciplines started using phrases such as ‘garrison state’ and ‘garrison mentality’ to describe societies where military imperatives predominated. They frequently argued that a perpetual sense of threat and a profound feeling of isolation shaped the outlook of residents in these communities. Such terms continue to surface in contemporary scholarship and popular media, where ‘the garrison’ often remains a stock image. Evidence from eighteenth-century Gibraltar, however, suggests that traditional readings of the garrison as an insulated fortress should be reconsidered. The survival of this strategic outpost actually required that colonial administrators rely on an array of foreigners to keep it supplied during times of both war and peace. At Gibraltar, the garrison was neither isolated from its surrounding environment nor perpetually threatened by its cosmopolitan residents—instead, inescapable dependence on a motley local population often rendered administrators willing to accommodate the alien in their midst and to acknowledge the interconnections between military and civilian.  相似文献   
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This paper takes as its focus the Midland Group Gallery in order to, first, make a case for the consideration of the geographies of art galleries; second, highlight the importance of galleries in the context of cultural geographies of the 1960s and third, discuss the role of provinciality in the operation of art worlds. In doing so, it explicates one set of geographies surrounding the gallery—those of the local, regional and international networks that are connected to produce art works and art space. It reveals how the interactions between places and practices outside of metropolitan and regional hierarchies provide a more nuanced insight into how art worlds operated during the 1960s, a period of growing internationalism of art, and how contested definitions of the provincial played an integral role in this. The paper charts the operations of the Midland Group Gallery and the spaces that it occupied to demonstrate how it was representative of a post-war discourse of provincialism and a corresponding re-evaluation of regional cultural activity.  相似文献   
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The "panoptic" logic of social control analyzed by Michel Foucault plays an important part in regulating "normal" citizens of the modern world as well as institutionalized populations. However, control of the unconfined presupposes certain conditions not paid adequate attention by Foucault, especially the requirement that people be individually identifiable in most activities, and that private property be located at fixed addresses. In order to explore the importance and the implications of these and other preconditions, this paper examines the strategies with which the U.S. government attempted to bring the Oglala Lakota under administrative control during the first decade of their settlement around the Red Cloud Agency on the northern Great Plains. Oglala society exhibited none of the hypothesized prerequisites for social control by the U.S. government at the beginning of the decade, but by 1879, the rudiments of a working system were in place. This story of the struggles surrounding its imposition robs modern social control of its seeming naturalness and immutability, brings into a critical light many of the spatial conditions we take for granted in today's world, and suggests the importance of a new, relatively unexplored dimension of the historical geography of American Indians and their dealings with White society.To the men of my time was appointed the task of taking the raw and bleeding material which made the hostile strength of the plains Indians, of bringing that material to the mills of the white man, and of transmuting it into a manufactured product that might be absorbed by the nation without interfering with the national digestion…In the language of the bounding West in which he made his habitat, it may be said that, in 1871, the Indian was "halter-broke but he had not yet been bitted".James McLaughlin,Former Agent to the Standing Rock Sioux  相似文献   
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This paper challenges the proposition that connecting with nature through direct encounters with nonhumans promotes ethical regard for them. It probes the limits of more-than-human ethics founded on personal encounters which struggle to cross distance and difference. I consider how personal engagement influences ethical perspectives and attend to processes by which care for nonhumans is learnt. Empirical research in community gardens reveals diverse relationships with nonhumans and underlines the importance of attending to qualities of relating. I propose typologies for thinking through more-than-human relationships, organising them according to degree of care. The research finds limits to gardening’s potential to promote more care-full relations with others, with care limited by the prevalence of instrumental relationships with nonhumans. Learning to care for nonhumans requires a sense of connection to combine with disconnection gained through reflection, setting specific encounters within the context of more extensive relations and their power dynamics. More important than encounters teaching care for specific nonhuman dependents are those promoting understanding of the interdependent nature of more-than-human communities, and that stimulate reflection on the cumulative impact of a human tendency to forget this.  相似文献   
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Diffusion research often characterizes the role of the federal government in innovation adoption as a supportive one, either increasing the likelihood of adoption or its speed. We examine the adoption of medical marijuana laws (MMLs) from 1996 to 2014 to shed light on what motivates states to adopt innovations that are in explicit defiance of federal law. Furthermore, we examine whether federal signals have any influence on the likelihood of adoption. In doing so, we utilize implementation theory to expand our understanding of how the federal government's position impacts state policy innovation adoption. We find mixed evidence for the influence of federal signals on the adoption of MMLs. The results suggest that medical marijuana policies are much more likely to be adopted in states when proponents have the political or institutional capital, rather than a medical or fiscal need. Moreover, this political capital is sufficient independent of the federal government's real or perceived position.  相似文献   
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