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   3000篇
  免费   66篇
  2020年   20篇
  2019年   23篇
  2018年   327篇
  2017年   236篇
  2016年   281篇
  2015年   51篇
  2014年   36篇
  2013年   599篇
  2012年   84篇
  2011年   208篇
  2010年   247篇
  2009年   97篇
  2008年   110篇
  2007年   178篇
  2006年   69篇
  2005年   52篇
  2004年   42篇
  2003年   26篇
  2002年   19篇
  2001年   17篇
  2000年   10篇
  1999年   16篇
  1998年   15篇
  1997年   6篇
  1996年   9篇
  1995年   18篇
  1994年   12篇
  1993年   9篇
  1992年   12篇
  1991年   9篇
  1990年   8篇
  1989年   12篇
  1988年   13篇
  1987年   16篇
  1986年   11篇
  1985年   14篇
  1984年   11篇
  1983年   9篇
  1982年   10篇
  1981年   12篇
  1980年   14篇
  1979年   7篇
  1978年   8篇
  1977年   6篇
  1976年   8篇
  1975年   8篇
  1972年   10篇
  1971年   5篇
  1970年   7篇
  1969年   5篇
排序方式: 共有3066条查询结果,搜索用时 15 毫秒
981.
Recently found open-air flint extraction and workshop sites in the Eastern Galilee, Israel, are the focus of this paper. Lithic assemblages from among a few of the thousands of tailing piles documented in a field survey, indicate mostly late Lower Palaeolithic/Middle Palaeolithic and rarely Neolithic/Chalcolithic affinities. These discoveries substantially increase our knowledge of the scope of lithic extraction and reduction in northern Israel in these periods. The new sites are located on a 25 km2 outcrop of flint-bearing Eocene limestone indicating intensive extraction of large amounts of flint, possibly beyond immediate local consumption requirements. After describing the new sites, we discuss their relation to nearby Middle and Lower Palaeolithic sites; possible resource management scenarios; chronology and duration of the extraction and reduction activity; and the sites as possible landmarks. A key question is the extent of the flint distribution area, or, more precisely, whether this region was a dominant mega-quarry for northern Israel and/or Southern Lebanon in the periods discussed.  相似文献   
982.
The geochemical compositions for obsidian from two of the most important sources on the Japanese island of Hokkaido, Shirataki and Oketo, are presented. This work represents the first systematic study of obsidian geochemistry on Hokkaido from the view of modern methodological standards. The study was performed with the help of neutron activation analysis to determine the concentrations for 28 elements. The results obtained allow us to subdivide both sources into two geochemical groups (Shirataki‐A and ‐B; and Oketo‐A and ‐B), with each representing an individual sub‐source. Obsidian from both Shirataki and Oketo sources is identified at archaeological sites located on Hokkaido, on the neighbouring Sakhalin Island and Kurile Islands, and in the lower course of the Amur River basin. The distance of obsidian transport during the Upper Palaeolithic was up to ~250 km, and in the following Neolithic and Palaeometal periods up to ~1200 km. This testifies to the wide distribution of Hokkaido obsidian to archaeological complexes in North‐East Asia and its active transport/exchange in prehistory. The data presented here should be used as a reference for the obsidian geochemistry of Shirataki and Oketo sources from now on.  相似文献   
983.
Excavations carried out in Cuma by the Centre Jean Bérard archaeologists have uncovered a large quantity of pottery. This study is focused on cooking ware and on internal red‐slip cookware, also known as Pompeian Red Ware (Rosso Pompeiano), dated from the first century bc to the first century ad . A comparison with the minero‐petrographic composition of beach sands collected along the Bay of Naples coastline highlights the provenance of the temper from the Somma‐Vesuvius area, marked by leucite‐bearing scoriae and garnet. Petrochemical analyses allow us to distinguish two main groups of pottery characterized by different technological options based on the amount of temper and on the type of clay. X‐ray diffraction and scanning electron microscope data demonstrate improved accuracy in the production of Rosso Pompeiano, especially with regard to firing control, which was in a prevailing oxidizing atmosphere and in a narrow thermal range, between about 800 and 900°C.  相似文献   
984.
Fifty‐three ceramic samples were collected in the area of the colonial city of Riobamba, Ecuador (today Sicalpa/Cajabamba). Neutron activation analysis was used to attempt to establish elemental compositions, and from these gain information on the manufacturing locations of these samples. Colonial samples imported from Panama were separable by their high Cs contents, and can be sorted into glazed and unglazed industries based on As and Cs. High As concentrations in several sherds indicate an origin near Cuenca, in the Southern Highlands of Ecuador, for both colonial and Inca samples. Inca and colonial Quito samples from the north of the country are identifiable through high Na combined with low Sc and Cr concentrations. Locally produced Puruhá, unglazed colonial and majolica samples form a group indicative of local Riobamba elemental composition.  相似文献   
985.
World‐renowned Renaissance astronomer Tycho Brahe died on 24 October 1601, after 11 days of illness. Several conspiracy theories regarding his death have been aired, the first shortly after his death by William Shakespeare in the play Hamlet, published in 1603. A key factor in the still lively debate is whether he was administered mercury—as medicine by his own hand, or as poison by an unfriendly hand. In 2010, Brahe's grave was reopened and samples of his bones, hair, teeth and the textiles were procured and analysed. Here, we present evidence that Brahe was not administered lethal doses of mercury.  相似文献   
986.
987.
988.
989.
990.
Reverte C, José Manuel. Antropología Médica, Volume I. Madrid: Editorial Rueda, 1981. xvii + 815 pp. including figures, photographs, and bibliography. $40.00 cloth.  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