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   4487篇
  免费   150篇
  2020年   49篇
  2019年   93篇
  2018年   107篇
  2017年   116篇
  2016年   119篇
  2015年   92篇
  2014年   87篇
  2013年   1318篇
  2012年   139篇
  2011年   123篇
  2010年   156篇
  2009年   147篇
  2008年   96篇
  2007年   116篇
  2006年   106篇
  2005年   66篇
  2004年   55篇
  2003年   54篇
  2002年   65篇
  2001年   72篇
  2000年   56篇
  1999年   62篇
  1998年   63篇
  1997年   50篇
  1996年   57篇
  1995年   45篇
  1994年   49篇
  1993年   45篇
  1992年   42篇
  1991年   37篇
  1990年   24篇
  1989年   43篇
  1988年   37篇
  1987年   50篇
  1986年   37篇
  1985年   41篇
  1984年   50篇
  1983年   43篇
  1982年   33篇
  1981年   42篇
  1980年   52篇
  1979年   45篇
  1978年   27篇
  1977年   50篇
  1976年   34篇
  1975年   37篇
  1974年   23篇
  1972年   25篇
  1970年   23篇
  1969年   22篇
排序方式: 共有4637条查询结果,搜索用时 15 毫秒
131.
Archaeological and ethnological evidence from the site of Efutu in Ghana is used to indicate the African cultural background of people imported into the Caribbean for enslavement in historical times. Historical, oral and ethnographic data are cited as bases for identifying the characteristics that enabled the enslaved people in the Caribbean successfully to establish independent communities and to put up a prolonged resistance against colonial powers. The heritage of Maroon communities in Jamaica is then discussed in order to identify continuities and discontinuities in African traditions among Caribbean societies.
Résumé Les témoignages archéologiques et ethnologiques du site d'Efutu au Ghana servent à donner des indications sur le passé culturel africain des gens importés aux Antilles comme esclaves aux temps historiques. Des données historiques, orales et ethnographiques sont citées comme bases pour l'identification des caractéristiques ayant permis aux esclaves des Antilles de parvenir à établir des communautés indépendantes et d'opposer une résistance prolongée aux puissances coloniales. L'héritage des communautés d'esclaves marrons en Jamaïque est ensuite discuté afin d'identifier les continuités et discontinuités des traditions africaines parmi les sociétés caraïbes.
  相似文献   
132.
Several samples of pyramids from Giza were obtained. The samples were analysed by scanning electron microscopy, electron diffraction by X-rays, powder X-ray diffraction, inductively coupled plasmography, Fourier-transform infrared spectroscopy and other techniques. Some scientists who have recently studied the pyramids have suggested that the pyramids were poured into place, stone by stone. The prevailing theory among Egyptologists is, of course, that the pyramids were built from blocks of natural stone. All of the results obtained during this study directly support the concept that the pyramids are made of limestone and are not cementitious in nature.  相似文献   
133.
134.
135.
Mining of mineral sands has taken place on North Stradbroke Island for over 40 years. Revegetation of mined areas creates a mosaic of seral classes. For a mine site in the northwest of the island, Landsat Thematic Mapper data were used successfully to map the distribution of seven seral classes resulting from mining rehabilitation. Faecal pellet counts were used to assess usage of these areas and surrounding natural forest by swamp wallabies, Wallabia bicolor. Results indicated that revegetated sites from 2 to 4 years in age were heavily used by wallabies. Older revegetated sites, dominated by senile Acacia cunninghamii, and offering little or no forage, were avoided. Swamp wallabies used revegetated sites for night-time feeding sessions and rested, during the day, in surrounding eucalypt forest.  相似文献   
136.
In skeletons excavated from Woodland sites, copper and barium levels are found to have been contaminated by influx from the soil environment. Electron microprobe scans for both elements show build-up along the outer surface of femur cross sections. Elemental levels for Cu and Ba are lower in the femur or fibula than in the more porous rib. The distribution of Cu in the immediately surrounding soil is highly anisotropic. These observations indicate that Cu and Ba should not be used for dietary inferences about ancient populations without independent evidence that diagenesis is not important.  相似文献   
137.
138.
139.
Book reviews     
Adam Watson, Diplomacy: the dialogue between states. Eyre Methuen, London, 1982, pp.239. $28.95.

Desmond Ball and J.O. Langtry (eds). Civil Defence and Australia's Security in the Nuclear Age. Strategic and Defence Studies Centre, Australian National University, Canberra, and George Allen and Unwin Australia, Sydney. 1983, pp. 359. $12.95.

Bruce Grant, Gods and Politicians. Allen Lane, Ringwood, Victoria, 1982, pp.wi + 190. $16.95.

B.A. Santamaria, Santamaria, Against the Tide. Oxford University Press, Melbourne, 1981, pp. 382. $22.50

M.M. Kritz. C.B. Keely and S.M. Tomasi (eds.), Global Trends in Migration: Theory and Research on International Population Movements. The Centre for Migration Studies, New York, 1981, pp.xi + 433. $US14.95 (cloth), $US9.95 (paper).

Robert Cassen, Richard Jolly, John Sewell and Robert Wood (eds). Rich Country Interests and Third World Development. Croom Helm, London and Canberra, 1982, pp. 369. $27.75.

David Childs, The GDR: Moscow's German Ally. George Allen and Unwin, London, 1983, pp. xiii + 346. $49.95 (cloth), $19.95 (paper).

Alexander Shtromas, Political Change and Social Development; The Case of the Soviet Union. Verlag Peter Lang, Bern, 1981, pp 173. S Fr 40.

Joel K. Goldstein, The Modern American Vice Presidency. The Transformation of a Political Institution. Princeton University Press, Princeton, N.J., 1982, pp. xxii + 409. $US36.50 (cloth) $US 10.50 (paper).

Colin Mackerras, Modern China ‐ A Chronology from 1842 to the Present. Thames and Hudson, London, 1982, pp. 703. $60.00

John H. Fincher, Chinese Democracy: The Self Government Movement in Local. Provincial and National Politics, 1905–1914. Australian National University Press, Canberra, 1981, pp. 27s6. $23.95.

A.J. Youngson, Hong Kong: Economic Growth and Policy. Oxford University Press, Hong Kong, 1982, pp. 163. $10.95.

Peter Wesley‐Smith, Unequal Treaty 1898–1997: China. Great Britain and Hong Kong's New Territories. Oxford University Press, Hong Kong. 1980, pp. XV + 270. $39.00.

Michael Leifer, Indonesia's Foreign Policy. George Allen & Unwin, London, 1983, pp. xvii + 198. $39.95.

Grant Evans, The Yellow Rainmakers. New Left Books/Verso, London, 1983, pp. 202. $33.50 (cloth) $10.50 (paper).

Stewart Firth, New Guinea Under the Germans. Melbourne University Press, Melbourne, 1982, pp. xiii + 216. $25.00.

R.J. May (ed.), Micronationalist Movements in Papua New Guinea. Political and Social Change Monograph No. 1, Department of Political and Social Change, Research School of Pacific Studies, Australian National University, Canberra, 1982, pp. xi. + 486 $9.50.

Politics in Melanesia. Institute of Pacific Studies, University of the South Pacific, Suva, 1982, pp. xxi + 170. $4.00

Foreign Forces in Pacific Politics. Institute of Pacific Studies, University of the South Pacific, Suva, 1983, pp. xv + 325, $6.00.

Mike Moore, A Pacific Parliament. Asia Pacific Books, Wellington and the Institute of Pacific Studies, University of the South Pacific, Suva, 1982, pp. 86. No price given.

Australia and the South Pacific. Conference Papers and Reports. Centre for Continuing Education, Australian National University, Canberra, 1983, pp. 157. $8.00.

Alan R. Taylor, The Arab Balance of Power, Syracuse University Press, Syracuse, 1982, pp. xii + 165. $US22.00 (cloth) $US11.95 (paper).

Tareq Y. Ismael, Iraq and Iran: Roots of Conflict. Syracuse University Pess. Syracuse. 1982, pp xii + 226. $US24.00 (cloth) $US12.95 (paper).

Peter Gubser, Jordan: Crossroads of Middle Eastern Events. Croom Helm, London and Westview Press, Boulder, Colorado, 1983, pp. xi+ 139. £13.50.

Ibrahim Ibrahim (ed.), Arab Resources: The Transformation of a Society. Croom Helm, London, 1983, pp. 304. $24.25.

David Goldsworthy, The International Politics of the Namibian Dispute, Discussion Paper No. 3, 1982, pp. 41

Jock McCulloch, South Africa's Invasion of Angola: Many Reasons Why. Current Issues Brief No. 7, 1981, pp. 10 both published by the Legislative Research Service, Department of the Parliamentary Library, Canberra.  相似文献   

140.
Among the manifestations of radioactive decay which can be etched to optical visibility on the surface of mica are tracks from nuclei recoiling from alpha emission, called ‘alpha-recoil tracks’. If, beforeetching, the mica is heated to temperatures of the order of 600°C, all evidence of these tracks is annealed from muscovite mica in a few minutes. Alpha activity observed on mica from pot sherds, from stones surrounding fire places, from fire pits, and fired daub may constitute an alpha-recoil track clock which started at the moment of the last firing of the artifacts.  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