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   858篇
  免费   41篇
  2023年   5篇
  2020年   16篇
  2019年   17篇
  2018年   25篇
  2017年   41篇
  2016年   28篇
  2015年   31篇
  2014年   31篇
  2013年   268篇
  2012年   25篇
  2011年   24篇
  2010年   18篇
  2009年   15篇
  2008年   19篇
  2007年   11篇
  2006年   21篇
  2005年   6篇
  2004年   14篇
  2003年   10篇
  2002年   12篇
  2001年   10篇
  2000年   13篇
  1999年   14篇
  1998年   11篇
  1997年   13篇
  1996年   4篇
  1995年   12篇
  1994年   4篇
  1993年   10篇
  1992年   5篇
  1991年   4篇
  1990年   7篇
  1989年   10篇
  1988年   8篇
  1987年   10篇
  1986年   11篇
  1985年   8篇
  1984年   8篇
  1983年   6篇
  1982年   10篇
  1981年   5篇
  1980年   11篇
  1979年   5篇
  1978年   4篇
  1977年   10篇
  1976年   7篇
  1973年   4篇
  1971年   7篇
  1970年   6篇
  1966年   4篇
排序方式: 共有899条查询结果,搜索用时 15 毫秒
51.
52.
Based on existing work, there are clear differences in the incidence of degree holders across the urban–rural hierarchy in favor of large urban areas. In large part, this gradient can be traced to the higher probability of obtaining a degree among residents of larger urban centers. Utilizing data from the Youth in Transition Survey (YITS), this paper explores factors that may account for university participation among Canadian youth. It asks whether this difference is due to local access to universities, family characteristics (e.g., parental income, education, and immigrant status), and local labor market characteristics that may increase the incentive for urban youth to attend university.  相似文献   
53.
54.
In this paper we debate the interpretation of embodied experience on international volunteering placements. Drawing on six in-depth interviews with volunteers recently returned from Northern Thailand, we document the affects and emotions that play a key role in the formation of volunteer–host relations. We then present two interpretations of the data, conceptualising power-body relations in two different ways: from power’s affective and emotional literacy, to the body’s autonomous capacities. With these two interpretations at hand we then consider the performative nature of academic labour and make the case, following the work of feminist geographers J.K. Gibson-Graham, for a research praxis that does not set limits on subjectivity but rather excavates – and writes into being – the possible. We therefore argue for a conceptualisation and interpretation of embodied experience in volunteering as a site of potential transformation and transcendence of the inequalities that otherwise set the conditions of the volunteer–host encounter.  相似文献   
55.
Zhen, Y.Y., Wang, G.X. &; Percival, I.G., August 2016. Conodonts and tabulate corals from the Upper Ordovician Angullong Formation of central New South Wales, Australia. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

The Angullong Formation is the youngest Ordovician unit exposed in the Cliefden Caves area of central New South Wales. Its maximum age is constrained by a Styracograptus uncinatus graptolite Biozone fauna at the very top of the underlying Malongulli Formation, but the few fossils previously reported from higher in the Angullong Formation are either long-ranging or poorly known. From allochthonous limestone clasts in the middle part of the formation, we document a conodont fauna comprising Aphelognathus grandis, A. solidum, Aphelognathus sp., Aphelognathus? sp., Belodina confluens, Drepanoistodus suberectus, Panderodus gracilis, Panderodus sp., Phragmodus undatus, Pseudobelodina inclinata and Pseudobelodina? sp. aff. P. obtusa, which supports correlation with the Aphelognathus grandis Biozone (late Katian) of the North American Midcontinent succession. The species concepts of Aphelognathus and Pseudobelodina are reviewed in detail. Associated corals are exclusively tabulates, dominated by agetolitids, including Agetolites angullongensis sp. nov., Heliolites orientalis, Hemiagetolites breviseptatus, Hemiagetolites sp. cf. H. spinimarginatus, Navoites sp. cf. N. circumflexa, Plasmoporella bacilliforma, P. marginata, Quepora sp. cf. Q. calamus and Sarcinula sp. Affinities of the coral fauna from the Angullong Formation are closer to faunas from northern NSW and northern Queensland than to the locally recognized Fauna III of late Eastonian age in central NSW. We propose a subdivision of Fauna III to account for this difference, with the late Katian Fauna IIIB characterized by the incoming of agetolitid corals. The currently known distribution of representatives of this group with adequate age constraints suggests that agetolitids possibly originated in North China, subsequently migrating to Tarim, South China and adjacent peri-Gondwanan terranes while also spreading eastward to northern Gondwana, where they progressively moved through eastern Australia to reach the central NSW region by the early Bolindian.

Yong Yi Zhen* () and Ian G. Percival (), Geological Survey of New South Wales, W.B. Clarke Geoscience Centre, 947953 Londonderry Road, Londonderry, NSW 2753, Australia; Guangxu Wang (), State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, 39 East Beijing Road Nanjing 210008 PR China.  相似文献   
56.
Recent excavations in south‐eastern Wadi ‘Araba in Jordan have revealed the first early Islamic‐period copper‐smelting site known in the eastern side of the valley, which extends south of the Dead Sea to the Gulf of ‘Aqaba. Five test pits were excavated in 2012 at Khirbat al–Mana‘iyya, a prominent copper‐smelting camp in south‐eastern Wadi ‘Araba, Jordan. The results of these excavations demonstrate that the site was primarily active in the seventh–ninth century AD. Its distance from the copper sources of south‐west ‘Araba suggests that its location was chosen based on proximity to wood and water resources, rather than copper ore deposits. The discovery that the site dates to the early Islamic period has implications for previous and future work in south‐east ‘Araba. In particular, it challenges the common—until now—view of the region as virtually devoid of settlement during this period.  相似文献   
57.
While Indonesia’s efforts at countering violent extremism have enjoyed some successes, a section of its Islamist community remains committed to militant jihadism. The return from overseas of hundreds of militants linked to ISIS means that there is now a greater need than ever for interventions to prevent radicalisation – and for programs to reintegrate militants back into society. Drawing on 20 selected interviews with former jihadists, this article asks how successful official efforts have been at disengaging those convicted under Indonesia’s Anti-Terrorism Law from violent extremism. A significant minority remain welded to a militant mindset: “committed jihadists” who are likely to reoffend. Some former jihadists have “disengaged provisionally” but remain vulnerable: they have only disengaged for tactical or practical reasons. Yet some have also begun to disengage emotionally. While they may not disavow completely the use of force, these “provisionally deradicalised” activists have moved closer to that minority of interviewees who are “fully deradicalised”. Using this four-part typology of the pathways by which some militant jihadists have disengaged but others have not, this article finds that disengagement is a gradual process shaped by social networks. Consequently, it is suggested that a variety of methods be used to promote disengagement both before and after inmates leave prison.  相似文献   
58.
59.
60.
The extent to which North Atlantic Holocene climatic perturbations influenced past human societies is an area of considerable uncertainty and fierce debate. Ireland is ideally placed to help resolve this issue, being occupied for over 9000 yr and located on the eastern Atlantic seaboard, a region dominated by westerly airflow. Irish bog and lake tree populations provide unambiguous evidence of major shifts in surface moisture through the Holocene similar to cycles recorded in the marine realm of the North Atlantic, indicating significant changes in the latitude and intensity of zonal atmospheric circulation across the region. To test for human response to these cycles we summed the probabilities of 465 radiocarbon ages obtained from Irish archaeological contexts and observe enhanced archaeological visibility during periods of sustained wet conditions. These results suggest either increasing density of human populations in key, often defensive locations, and/or the development of subsistence strategies to overcome changing conditions, the latter recently proposed as a significant factor in avoiding societal collapse. Regardless, we demonstrate environmental change is a significantly more important factor in influencing human activity in the landscape than has hitherto been acknowledged.  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