首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   48篇
  免费   3篇
  2023年   3篇
  2020年   2篇
  2019年   2篇
  2018年   4篇
  2017年   3篇
  2016年   1篇
  2014年   2篇
  2013年   20篇
  2012年   2篇
  2011年   1篇
  2010年   2篇
  2009年   1篇
  2005年   1篇
  2003年   1篇
  1999年   1篇
  1988年   2篇
  1981年   1篇
  1974年   1篇
  1955年   1篇
排序方式: 共有51条查询结果,搜索用时 15 毫秒
21.
Discourses on “illegal” or informal small-scale mining (galamsey) have presented it largely as a menace. Using Ghana as the focus of our study, we present a counter-narrative to the predominant discourse. Employing qualitative in-depth interviews with 193 local galamsey operators, the study found that economic factors coupled with the combative posture of state regulatory agencies explain the persistence of illegal activity. Although galamsey is not problem-free, the study revealed it is the livelihood support base of such communities, providing jobs and incomes to many households. Since mineral-rich local communities, at least, in part, depend on galamsey, the state and its regulatory agencies could collaboratively work with local agencies and mineral-rich communities to fully exploit the hidden treasures in galamsey while reducing the proximate negative effects.  相似文献   
22.
Eggshells are unusual finds in the Iron Age of eastern Europe (500 BC–1200 AD) deserving extra attention in terms of analysis as well as interpretation. This paper discusses two rare eggshell finds, discovered in female burials at the conversion period (12th–13th century AD) cemetery at Kukruse, NE Estonia. Our multianalytical study combining FT-IR, SEM(-EDS), microscopy and ZooMS provides an overview of methods applicable for identifying egg species, their predepositional history and curation. Based on the analytical results and the comparative analysis of the content and context of these two burials, we argue that different aims and connotations lay behind depositing eggs as burial goods, allowing well-supported interpretations of both pagan and Christian religious worldviews simultaneously.  相似文献   
23.
24.
25.
Study of an ostracode assemblage from the Miocene Fyansford Formation near Mornington allows determination of the principal characteristics of the hydrologic environment at that time.

Palaeodepth was upper epibathyal (about 150–250 m). The oxygen minimum zone mostly was weakly demarcated at about O2 5 ml/l. Productivity was good and the benthic ostracode microfauna was rich and varied. Occasionally, a sudden and strong increase in productivity occurred which correlated to a rapid and well marked increase in the oxygen minimum zone. Physico-chemical factors, which developed following bacterial breakdown of organic matter that had accumulated on the bottom, are reflected in Bradleya shells by distinct signs of aggradation/degradation. A few allochthonous forms from the nearby continental shelf were transported downwards onto this part of the upper slope. Bottom currents contributed (by furrowing) to the formation of calcareous ‘hard grounds’.

Bradleya morningtonensis n.sp. is described as new.  相似文献   
26.
27.
Under the right conditions, compounding socio‐political and economic change can dramatically alter government policy. From 2000, Western Australia, a resource‐rich jurisdiction, experienced significant change owing to a once‐in‐a‐generation resources boom, which forced a break with earlier development approaches. In 2008, regional interventionism returned to the State via the State Government's Royalties for Regions program. Departing from the neo‐liberal tradition, the program allocated 25 per cent of the State's royalty income to non‐metropolitan regions, over and above existing regional allocations, and its success remains disputed. While it is easy to question the program retrospectively, the socio‐economic and political circumstances from 2000 to 2008 reveal a “perfect storm” of conditions enabling the transition from neo‐liberalism to interventionism in regional development. This paper sets out to understand the multi‐faceted conditions that enabled the dramatic paradigm shift embodied by the program. To this end, it examines the State's rural–urban settlement dichotomy, its staples economy, and the policy context leading up to the program. Following that, the paper proposes a causal framework mapping out the factors driving and rationalising the program. These factors are then examined in detail and include perceived rural voter disenchantment, ineffectual regional development policy, the State's mining boom, inadequate regional development funding, the contrasting fortunes of two regions (illustrative of the impact of growth, and the lack thereof), and the political manoeuvring during the 2008 election. Finally, the paper concludes by considering how the conversion of these conditions resulted in the State's most significant regional policy redirection in decades.  相似文献   
28.
Between 1831 and 1833 the Chief Justice of the Cape Colony, Sir John Wylde, was involved in a scandal surrounding anonymous accusations of incest resulting from the alleged pregnancy of his unmarried daughter. The rumours led to an official inquiry by the secretary of state. The resulting political crisis took place against a background of social tension over impending slave emancipation. The records of the inquiry, together with contemporary comment, form the basis for a discussion of how gender roles, gossip and a separation between public and private spheres informed the operation of Cape colonial politics and society.  相似文献   
29.
30.
Dietary adaptations of prehistoric hunter-gatherers from Neolithic and Early Bronze Age cemeteries in the Little Sea region of Cis-Baikal (the region to the west and north of Lake Baikal) are explored using stable isotopes of carbon and nitrogen. Stable isotope data, including stable carbon isotopes from bone carbonate, are presented for 22 individuals from the site of Kurma XI, dated to approximately 6500 B.P. to 4000 B.P. Data are compared to previously analyzed individuals from the larger Early Bronze Age cemetery, Khuzhir-Nuge XIV (Katzenberg et al., 2009 JAS) and to smaller sites located along the shore of the Little Sea, including sites on Olkhon Island. An extensive collection of fauna, both prehistoric and modern, from the Little Sea and neighboring regions is also analyzed for stable isotopes of carbon and nitrogen. Clear distinctions are found in modern fish recovered from the Little Sea, in contrast to those from the open waters of the lake and from the neighboring Angara and Lena rivers. Considerable variation is seen in stable carbon isotope ratios from fish while stable nitrogen isotope ratios are not as variable, regardless of habitat. Isotope source modeling is used to assist in reconstructing past dietary adaptations. While there is ample evidence from other studies for cultural change over this temporal span, diet appears to have been relatively stable.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号