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   23篇
  免费   0篇
  2022年   1篇
  2019年   3篇
  2017年   1篇
  2016年   1篇
  2013年   5篇
  2012年   4篇
  2011年   1篇
  2009年   1篇
  2008年   4篇
  2007年   1篇
  2006年   1篇
排序方式: 共有23条查询结果,搜索用时 250 毫秒
1.
Tooth pendants of European elk, Eurasian beaver and brown bear are the most common artefact type in graves at Late Mesolithic Yuzhniy Oleniy Ostrov on Lake Onega, northwestern Russia. In one burial of a 20-35-year-old woman, 18 fragments of wild boar tooth pendants from at least five individuals were found. Wild boar was not a regular part of local fauna in the Mesolithic, and if these wild boars were hunted locally, they were very unusual game. These wild boar tooth pendants may also represent imported goods that came to Onega from a more southern area via exchange. It is also possible that the woman was not local but came from a region where wild boars were abundant and common game for Mesolithic people.  相似文献   
2.
The United States is more violent than Canada and it always has been. Even in the face of mass shootings, most Americans remain culturally and politically resistant to the sorts of gun control measures that have long existed in Canada. America’s unique gun culture is embedded in the history, imagery, and especially the mythology of the American frontier. Canada had its own frontier experience and has its own history of gun ownership, but it does not have a parallel gun culture. This article presents a comparative analysis of post-Civil War/post-Confederation frontier history and mythology, and examines the construction of contrasting cultural narratives of America’s “Wild West” and Canada’s “Mild West.” It suggests that US–Canadian differences in gun laws and gun culture—even in the borderlands region of Alberta/Montana—are better explained by the countries’ two different frontier mythologies than by their actual western histories.  相似文献   
3.
清人邓汉仪《诗观二集》中辑录了曹寅诗三首,出于其未刊诗稿《野鹤堂草》,因诗稿迷失,《楝亭集》未收。  相似文献   
4.
古建筑三维重建已成为历史遗迹保护与修复的重要内容。为了探讨三维激光扫描数据的获取流程、数据处理方法,以三维激光扫描获取的大雁塔海量点云数据为例,研究了古建筑三维重建中点云数据获取与处理的详细过程。联合Cyclone、AutoCAD和3D-Max软件的优点构建了大雁塔真实的横面、剖面、立面模型,其中重点研究了海量点云数据在Cyclone软件中分块建模的方法。结果表明:将拼接好的大雁塔海量点云数据分块建模,不仅加快了数据处理的速度,而且符合精度要求。在点云数据拼接时采用标靶拼接和同名点拼接相结合及测站间两两拼接之后再整体拟合平差的方法,减少了拼接中的误差,使每站拼接误差都不超过3cm。在建模过程中的墙体拟合是上万个点云经过平差计算得到,精度高达2mm。最后在3D-Max软件中组合、渲染和贴图,真实地构建了大雁塔三维立体模型。为古建筑数字化存档和后期的修缮工作提供了重要的依据。  相似文献   
5.
Pollen analyses of 13 archaeological sites in the Wadi Teshuinat area, in southwestern Fezzan, Libya, were synthesised to explore the potential contribution of palynological investigation to archaeological research in this area. During the Holocene, the sites were occupied by pre-Pastoral (hunter–gatherers) and Pastoral (pastoralists) cultures. Different pollen stratigraphies and floras characterised the diverse sites and the relevant cultural phases. Pollen data were reported by discussing the sites separately, and by combining them to interpret the regional data set. Emphasis was made on the anthropogenic pollen indicators and grasses, including large grass pollen grains (>40 μm), which were considered evidence of plant transport into the site. These were ethnobotanical markers, human-made evidence of plant harvesting by hunter–gatherers, or of animal breeding by pastoralists. The disappearance of some wild cereals was also observed, consistent with increasing climate dryness and land exploitation. Macroremains were used as a parallel tool to better understand plant exploitation in the region.  相似文献   
6.
明代的茶果银是一种重要的历史现象,有礼仪、贿赂和赋税三种性质。茶果在人际交往和祭祀神灵的过程中起着重要作用,有时用银钱代替实际的茶果,于是产生了礼仪性质的茶果银。明朝制度虽然禁止征收茶果银,但贿赂性质的茶果银实际上广泛存在,并造成严重危害。赋税性质的茶果银由礼仪和贿赂性质的茶果银演变而来,到清代成了正规的赋税。  相似文献   
7.
Computed tomography (CT) and traditional techniques were used to study the internal morphology of modern fruits of Pleiogynium timoriense (DC.) Leenh., and phosphatized and silicified fruits that were considered to belong to the genus. The results demonstrate that phosphatized fruits from the Oligocene–Miocene Dunsinane site at Riversleigh and silicified fruits from the Oligocene Glencoe Site, which are both in Queensland, are referable to Pleiogynium. The Riversleigh material (Pleiogynium wannanii Rozefelds, Dettmann & Clifford sp. nov.) is very similar to extant P. timoriense (DC.) Leenh. Both possess locules that, in the vertical axial plane, are asymmetrically reniform and enclosed by a two-layered endocarp, the inner layer woody and resistant to decay, the outer of fibres and parenchyma, surrounded by a mesocarp of fibres and sclereids and a parenchymatous exocarp. The outer mesocarp is sculpted by meridionally arranged, elongate depressions (germination apertures) situated at the dorsal surface of each locule; erosion of the mesocarp and outer endocarp provides passage for emergence of the embryo’s radicle on germination. The silicified material from Glencoe (P. parvum Rozefelds, Dettmann & Clifford sp. nov.) is smaller in all its parts and has locules that are ovate in the vertical axial plane. Discrete, cap-like, opercula are not evident in the fruit wall of the fossil and extant fruits studied. The presence of Pleiogynium, and associated taxa, indicates the existence of rainforest communities at Glencoe, and mixed open forest/rainforest at Riversleigh during Oligocene–Miocene times. The multilocular, fossil fruit described as Pleiogynium mitchellii Collinson, Manchester and Wilde from the Eocene deposits at Messel Quarry, Germany, is not considered to belong in the genus, as evidence of elongate depressions on the dorsal surface of the fruit stones has not been demonstrated conclusively, and its internal morphology/anatomy differs significantly from that of Pleiogynium.  相似文献   
8.
易溶盐富集是陕西西安大雁塔砖体表面风化、结构破坏、强度衰减的主要原因。为分析盐害对大雁塔砖体结构、强度的影响机理,采用以饱和硫酸钠溶液为介质,对大雁塔砖体进行易溶盐结晶循环模拟劣化试验。在Na2SO4反复结晶、溶解过程中,测定试样的质量、波速及单轴抗压强度等指标,分析其变化规律。结果表明,在盐害作用下,试验砖体表现出与塔体表面类似的风化破坏现象;Na2SO4晶体在试样孔隙内不断发育,晶体挤压效应导致孔隙率增大,内部结构破损;质量、波速、单轴抗压强度随循环的次数呈先增加后减小的变化规律。砖体对盐害耐受力约为砖体质量的0.5%。  相似文献   
9.
This research aims to shed light on the early stages of agricultural development in Northern Africa through the analysis of the rich macro-botanical assemblages obtained from Ifri Oudadane, an Epipalaeolithic–Early Neolithic site from North-East Morocco. Results indicate the presence of domesticated plants, cereals (Hordeum vulgare, Triticum monococcum/dicoccum, Triticum durum and Triticum aestivum/durum) and pulses (Lens culinaris and Pisum sativum) in the Early Neolithic. One lentil has been dated to 7611 ± 37 cal BP representing the oldest direct date of a domesticated plant seed in Morocco and, by extension, in North Africa. Similarities in both radiocarbon dates and crop assemblages from Early Neolithic sites in Northern Morocco and the Iberian Peninsula suggest a simultaneous East to West maritime spread of agriculture along the shores of the Western Mediterranean. Wild plants were abundantly collected in both the Epipalaeolithic and the Early Neolithic periods pointing to the important role of these resources during the two periods. In addition to fruits and seeds that could have been consumed by both humans and domesticated animals, fragments of esparto grass (Stipa tenacissima) rhizomes have been identified. This is a western Mediterranean native plant that may have been used as a source of fibres for basketry.  相似文献   
10.
Conran, J.G., Bannister, J.M. & Lee, D.E., 2013. Fruits and leaves with cuticle of Laurelia otagoensis sp. nov. (Atherospermataceae) from the early Miocene of Otago (New Zealand). Alcheringa 37, 496–509. ISSN 0311-5518.

Laurelia otagoensis sp. nov. Conran, Bannister & D.E. Lee (Laurales: Atherospermataceae) is described from the earliest Miocene Foulden Maar diatomite deposit, Otago, New Zealand. The new species is represented by mummified fossil leaves with well-preserved cuticle and associated clusters of achenes bearing persistent, long plumose styles. This basal angiosperm family is of significance because of its classic southern disjunctions and ecological importance in extant Gondwana-type rainforests, but has a very sparse fossil record. The present study describes one of very few convincing leaf fossils for Atherospermataceae and the only definitive fossil fruits. The presence of fossil Laurelia in Oligo–Miocene New Zealand combined with fossil leaf impressions from the late Eocene, Miocene dispersed cuticle and pollen from the Oligocene to Holocene shows that the family has had a long history in Cenozoic New Zealand. These new fossils also support palaeoclimatic data suggesting warmer conditions in the earliest Miocene of New Zealand.

John G. Conran [john.conran@adelaide.edu.au], Australian Centre for Evolutionary Biology & Biodiversity and Sprigg Geobiology Centre, School of Earth and Environmental Sciences, Benham Bldg DX 650 312, The University of Adelaide, SA 5005 Australia; Jennifer M. Bannister [jennifer.bannister@xtra.co.nz], Department of Botany, University of Otago, PO Box 56, Dunedin, New Zealand; Daphne E. Lee [daphne.lee@otago.ac.nz], Department of Geology, University of Otago, PO Box 56, Dunedin, New Zealand. Received 17.12.2012; revised 9.4.2013; accepted 15.4.2013.  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