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   174篇
  免费   9篇
  2021年   1篇
  2019年   3篇
  2018年   2篇
  2017年   4篇
  2016年   5篇
  2015年   5篇
  2014年   4篇
  2013年   33篇
  2012年   7篇
  2011年   6篇
  2010年   5篇
  2009年   8篇
  2008年   12篇
  2007年   2篇
  2006年   2篇
  2005年   4篇
  2004年   6篇
  2003年   2篇
  2002年   4篇
  2001年   4篇
  2000年   2篇
  1999年   4篇
  1998年   4篇
  1997年   1篇
  1996年   2篇
  1995年   1篇
  1993年   1篇
  1992年   2篇
  1991年   2篇
  1990年   1篇
  1989年   1篇
  1988年   2篇
  1987年   5篇
  1985年   3篇
  1982年   2篇
  1981年   6篇
  1980年   4篇
  1979年   6篇
  1978年   4篇
  1977年   4篇
  1976年   1篇
  1975年   2篇
  1972年   2篇
  1966年   1篇
  1955年   1篇
排序方式: 共有183条查询结果,搜索用时 15 毫秒
21.
22.
This paper is aimed at defining the artistic technique performed by the outstanding artist Isidoro Bianchi for the Baroque stucco decorations in the church of Santa Maria dei Ghirli (Campione d'Italia, Italy). Samples of stucco were examined by means of optical microscopy, scanning electron microscopy with a microprobe, X‐ray powder diffraction, Fourier transform infrared spectroscopy, gas chromatography–mass spectrometry and laser ablation mass spectrometry equipped with plasma source spectrometry. On the basis of the results obtained, art historians have made new hypotheses on the biography of the artist and on the historical location of his birthplace.  相似文献   
23.
24.
The article describes lithic industries of the Upper Paleolithic levels of Kulbulak, Uzbekistan, a key site in southwestern Central Asia based on materials from excavations at several sites in the western and northwestern Pamir– Tien Shan region (Kulbulak, Kyzyl-Alma-2, Dodekatym-2, and Shugnou). A new cultural and technological tradition is introduced, for which the authors suggest the name Kulbulakian. Its distinctive features are the bladelet technique and a microlithic set including backed pieces and triangular microliths. Stages in the evolution of the Kulbulakian tradition are reconstructed: origins, development, peak, and disappearance of the carinated technology. Industries belonging to this tradition have shaped the general appearance of the Upper Paleolithic in the area in question.  相似文献   
25.
26.
More than 400 fayalitic bloomery slags from prehistoric iron production sites in Upper and Lower Lusatia, eastern Germany, as well as bog iron ore samples and intermediary samples of the smelting process, were analysed by chemical and mineralogical techniques. While the precursor bog iron ores exploited in the two regions under investigation were very similar in composition, consisting of low‐manganese/low‐barium as well as high‐manganese/high‐barium types of ore, pronounced differences in slag composition were detected. Slags from 17 investigated sites in Upper Lusatia showed average P2O5 contents between 1 and 3 mass%, whereas slags from 15 investigated sites in Lower Lusatia were generally much richer in phosphorus, reaching values as high as 7 mass% P2O5. Since a reasonable correlation exists between calcium and phosphorus contents in the slags of the latter sites, it is conjectured that deliberate addition of CaO to the ore/charcoal charge of the bloomery furnace may have taken place in order to fix the phosphorus in the slags effectively. In many samples, this conjecture is being supported by the detection of a slag mineral Ca–Fe phosphate Ca9?xFe1+x(PO4)7 that presumably crystallized from a residual phosphorus‐rich melt and shows a cotectic relationship to both Ca‐rich fayalite and wustite, as well as to members of the solid solution series magnetite–hercynite.  相似文献   
27.
28.
29.
30.
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