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   1772篇
  免费   67篇
  2021年   9篇
  2020年   15篇
  2019年   26篇
  2018年   43篇
  2017年   39篇
  2016年   58篇
  2015年   35篇
  2014年   33篇
  2013年   526篇
  2012年   66篇
  2011年   70篇
  2010年   57篇
  2009年   62篇
  2008年   43篇
  2007年   57篇
  2006年   52篇
  2005年   25篇
  2004年   17篇
  2003年   15篇
  2002年   16篇
  2001年   18篇
  2000年   15篇
  1999年   26篇
  1998年   11篇
  1997年   15篇
  1996年   17篇
  1995年   19篇
  1994年   11篇
  1993年   19篇
  1992年   16篇
  1991年   21篇
  1989年   9篇
  1988年   14篇
  1987年   18篇
  1986年   23篇
  1985年   17篇
  1984年   16篇
  1983年   19篇
  1982年   23篇
  1981年   19篇
  1980年   14篇
  1979年   15篇
  1978年   14篇
  1977年   13篇
  1976年   15篇
  1975年   15篇
  1973年   11篇
  1970年   9篇
  1969年   11篇
  1967年   15篇
排序方式: 共有1839条查询结果,搜索用时 31 毫秒
101.
Recent developments in evolutionary psychology expanding on signaling theory provide key insights to the connections between expressing social commitments and resource rights. Credibility enhancing displays (CREDs) are a means to convince individuals of commitment to belief systems and can link costly acts or extravagant displays to social success. In the Salish Sea, the transition from labrets to cranial modification from 3200 to 1000 BP has often been framed in terms reflecting a shift from achieved to ascribed social status. Other researchers have argued that labrets may reflect village scale identity not tied to political power. We suggest that an explicitly evolutionary approach provides novel insights into the changing material expressions of Coast Salish social commitments, specifically reciprocal resource access. The shift to cranial modification reflects increased CRED investment and cost, but not necessarily a transition towards ascribed status. Instead this shift may be changing expressions of the same forms of social commitments.  相似文献   
102.
103.
A robust debate among coastal geomorphologists as to the processes by which beach‐ridge plains around Australia have formed was initiated by a former President of the Institute of Australian Geographers. This review gives special consideration to the work of Jack L. Davies, whose academic contributions to coastal geomorphology in Australia have not always been appropriately acknowledged when explaining how similar plains have evolved elsewhere in the world. Davies recognised that relatively steep storm waves caused erosion (cut) on beaches, whereas less steep long‐period swell waves returned sand (fill). He considered the beach berm to be the nucleus on which a beach ridge formed, which could subsequently develop into a foredune, in contrast to cobble ridges that were deposited during storms. Offshore conditions regulate supply of sand to the shoreline, partly through effects on wave refraction, with higher rates of supply where the nearshore is shallow. It was apparent to Davies that the elevation of successive ridges might, but not necessarily, provide evidence of past changes of sea level, despite adornment by variable amounts of windblown dune sand. Morphodynamic understanding of long‐term coastal evolution, based on radiocarbon dating chronologies, has demonstrated that Australian coastal plains formed over the past ~6,000 years when sea level has been close to its present level, in contrast to several documented locations in the northern hemisphere where the sea has been rising for the past few millennia. Particularly insightful were observations by Davies that ridge formation could be influenced by a range of factors including changes in sea level, storminess, or sediment supply. These factors acting singly or in combination seem likely to change in the future. Understanding such responses remains a high priority and can be addressed by new technologies, such as light detection and ranging, optically stimulated luminescence dating, ground‐penetrating radar, and computer simulation.  相似文献   
104.
ABSTRACT

Over the last five decades, the emergence of a sophisticated and multidimensional set of governance institutions in the predominantly Inuit regions of Canada and the circumpolar north has had a profound impact on the lives of Inuit peoples and the states in which they live. The region of Nunavik in northern Québec has played an important role in the political development of the Canadian and circumpolar Inuit, serving as both an institutional innovator and a key source of leadership at the regional, national, and international levels. Using a multilevel governance framework, this article explores the vertical and horizontal dimensions of Inuit governance in Canada and the circumpolar north. In particular, the article will focus on Nunavik’s contribution to and place in this multidimensional governance structure.  相似文献   
105.
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   
106.
Drawing on various historical documents, the article uses process tracing methods and analytic narratives to establish a relationship between historical contractual practices and state formation in nineteenth-century East Africa. I trace the process through which local political leaders historically sought to secure monopolistic deals over trade with foreign entrepreneurs through incomplete contracts for tangible economic goods (arms and slave trades, manufactured goods) and intangible political goods or services (security, knowledge, independence). By showcasing agents’ bargaining strategies in contractual agreements, the article sheds light on notions of sovereignty and independence articulated through public contracting in Africa’s political development. Historical understandings of notions of independence and sovereignty by procurement practitioners in East Africa provide seeds for thought in controversial debates about government outsourcing today. Is outsourced sovereignty always threatening? Can we outsource sovereignty and remain independent? These are perhaps the most important conceptual queries that make East Africa’s historical contractual experience pertinent today as new public-private partnerships for development, including government outsourcing, increasingly call for the use of private means to solve public problems in the developing countries.  相似文献   
107.
108.
The handle‐shaped artefact is a special jade object of the Three Dynasties (c.2000–200 bc ) period. The manufacturing technology and function of the handle‐shaped artefacts are widely questioned. In this paper, two handle‐shaped artefacts from Yinxu (c.1300–1046 bc ) are tested by digital microscope, Raman spectrometer and scanning electron microscope. The results indicate that the handle‐shaped artefacts might be made in four steps, namely rough shape cutting, edge reforming, handle making and single‐side polishing. It also suggests that the handle‐shaped artefacts might be used as sacrificial offerings, but not as hairpins or handles.  相似文献   
109.
Rock‐magnetic techniques were used to examine the topsoil layer of Kurma archaeological site (in the Olkhon region, on the north‐western coast of Lake Baikal, Siberia) in an effort to determine the possible sources of iron ores for iron‐smelting centres (at about the bc /ad boundary). Measurements have shown a magnetic enhancement of the topsoil due to magnetite grains resulting from weathering of strongly magnetic crystalline rocks. They have also revealed a preliminary picture of the distribution of strongly magnetic topsoils around the ancient iron‐smelting centres. Perhaps, in addition to traditional sources of raw materials, the ancient metallurgists used black sand talus as an ore deposit.  相似文献   
110.
Between 2000 and 2003, the Institute of Nautical Archaeology in collaboration with the Bulgarian Centre for Underwater Archaeology excavated the remains of an Ottoman period shipwreck in the southern bay of the town of Kitten, Bulgaria, dating to the reign of Sultan Selim III (1789–1807). This article discusses the smoking pipes and paraphernalia found on the wreck. The studied material offers a refinement to the dating of Ottoman pipes and proposes a reading of Ottoman pipe stamps from the Balkans that were hitherto considered undecipherable.  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