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   101篇
  免费   3篇
  2023年   3篇
  2020年   5篇
  2019年   3篇
  2018年   4篇
  2017年   5篇
  2016年   7篇
  2015年   3篇
  2014年   4篇
  2013年   28篇
  2012年   5篇
  2011年   1篇
  2010年   4篇
  2009年   2篇
  2008年   3篇
  2007年   4篇
  2005年   3篇
  2004年   1篇
  2003年   1篇
  2002年   2篇
  2001年   1篇
  1999年   1篇
  1997年   3篇
  1996年   1篇
  1995年   1篇
  1990年   1篇
  1982年   1篇
  1979年   2篇
  1978年   1篇
  1977年   3篇
  1975年   1篇
排序方式: 共有104条查询结果,搜索用时 31 毫秒
41.
Caves have yielded some of the most globally important archaeological sequences, but often their interpretation has suffered from assumptions about cave sedimentary processes. Caves contain distinctive sedimentary environments: this has major implications for the understanding of contained archaeological materials. This paper describes and analyses the Holocene sediments in the Haua Fteah, a sequence regarded as essentially continuous by the original excavator. 50 years after it was first excavated, the Haua's Epipalaeolithic to post-Classical chronological range and rich finds make it still the key Holocene archaeological site in North Africa. The reassessment shows, however, that the sequence is strongly discontinuous and this has major implications for the reinterpretation of the site, as the highly-resolved archaeological record is thus likely to reflect a series of brief occupations, rather than continuous human activity. As with many caves, the sedimentary record in the Haua Fteah is an extremely sensitive indicator of environments and processes in the wider landscape. Secure understanding of sedimentary process, from analysis of the highly individual records found in caves, is essential for full understanding of their contained archaeology.  相似文献   
42.
43.
This paper addresses the material boat culture of Vietnam both in its current context and more specifically through an assessment of how the boats of Vietnam have been studied in the past. It presents a comprehensive summary of past publications describing the construction, use and variety of boats in the region, from the earliest volumes to modern research projects, including the work of the US military. It highlights the rich diversity of construction approaches and boat‐types that are still built and used, and demonstrates the need for further field research to record the fast‐disappearing traditional boats of Vietnam. © 2010 The Authors  相似文献   
44.
45.
At the end of the First World War, the British government put into operation a Free Passage Scheme for ex-servicemen, ex-servicewomen and their dependants to emigrate to the colonies and dominions of the Empire. This scheme was driven by a complex network of interlinked beliefs and policies concerning both the relationship between the metropole and the Empire, and the perceived necessity for social stability in Britain and in the dominions and colonies. This article examines the Free Passage Scheme, paying particular attention to the ways in which it was envisaged as a means of restoring a gendered balance of the population in Britain, where young women outnumbered young men at the end of the war, and in the dominions, where men outnumbered women, and was also seen as a way of emigrating women whose wartime work experiences were understood to be in conflict with gendered identities in the post-war period. The article argues that the Free Passage Scheme needs to be understood as gendered, as it envisaged the transformation of female members of the auxiliary wartime services into domestic servants for the Dominions. The scheme's failure, it is argued, prefigures the failure of the far larger Empire Settlement Act of 1922 to emigrate large numbers of British women as domestic servants.  相似文献   
46.
47.
Transverse sections of Chirodipterus australis and Griphognathus whitei are used to demonstrate the histological structures of the rostral and symphysial tubuli in Devonian lungfish. The walls of the tubuli are composed of bony tissue indistinguishable from the cancellar bone found in dermal bone. It has many spaces and perforations, and is contiguous in places with the cancellar bone of the external dermal bone. The walls of lateral-line canals have the same histological structure as the walls of the tubuli; they also intercommunicate with them. The tubuli and the lateral-line canals open to the surface through large perforations on the external surface. In Griphognathus the walls of the tubes under the external dermal bone have two layers: the outer one is dense bone, but the inner one has the appearance of calcified fibrous connective tissue of the kind associated with the tissue surrounding the lateral-line canals in living lungfish. The tubuli are closely related to the pore-canal system via canals that penetrate the dermal bone; this same relationship has been observed in Dipnorhynchus and Speonesydrion. The intimate connection between the tubuli and the lateral-line system suggests that they were formed by the sinking of neuromasts into and under the external dermal bone, with their walls surrounded by cancellar bone.  相似文献   
48.
Summary.  This analysis of prehistoric pottery and clay samples from Cornwall demonstrates that the clay used to make Cornish gabbroic pottery in prehistory originated around the gabbro rock outcrop in a small area of the Lizard peninsula. The research uses petrographic and chemical analysis to subdivide the prehistoric pottery into six groups. Owing to the unusual geology of the Lizard these groups can be attributed to specific locations. The most abundant pottery fabric, Typical Gabbroic , was made using coarse clay which is mainly found in a 1 km2 area near Zoar. A finer version of this clay, found higher in the soil profile or slightly transported and redeposited, was used to make Fine Gabbroic pottery and an even finer variant called FNS (Fine Non-Sandy) Gabbroic . We identify for the first time here a Loessic/Gabbroic pottery fabric which can be matched exactly to clay found at Lowland Point. Serpentinitic/Gabbroic pottery was made using clay from the gabbro/serpentinite border zone. Pottery made from the Granitic/Gabbroic fabric did not match any clay from the Lizard, showing that gabbroic clay was sometimes removed and made into pottery elsewhere in Cornwall. The main clay source near Zoar was used for clay extraction throughout the Bronze Age and Iron Age for pottery which was traded all over Cornwall. Other gabbroic clay sources produced pottery only during certain periods and exclusively supplied particular settlements, such as the Loessic/Gabbroic fabric which was found only at Gear and Caer Vallack. The results suggest that pottery was produced by several small-scale cottage industries, which may have operated on a seasonal, part-time basis and probably formed only part of a wide range of activities located around the Lizard area.  相似文献   
49.
50.
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