全文获取类型
收费全文 | 751篇 |
免费 | 13篇 |
出版年
2024年 | 1篇 |
2023年 | 4篇 |
2022年 | 10篇 |
2021年 | 11篇 |
2020年 | 25篇 |
2019年 | 14篇 |
2018年 | 11篇 |
2017年 | 13篇 |
2016年 | 18篇 |
2015年 | 14篇 |
2014年 | 15篇 |
2013年 | 38篇 |
2012年 | 45篇 |
2011年 | 60篇 |
2010年 | 55篇 |
2009年 | 91篇 |
2008年 | 57篇 |
2007年 | 66篇 |
2006年 | 46篇 |
2005年 | 51篇 |
2004年 | 21篇 |
2003年 | 30篇 |
2002年 | 11篇 |
2001年 | 14篇 |
2000年 | 17篇 |
1999年 | 9篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有764条查询结果,搜索用时 31 毫秒
1.
Non‐invasive materials characterisation of reconstructed statues of Emperor Qin Shihuang's Terracotta Army has revealed distinct micro‐geochemical patterning within the clay paste used in their manufacture. The significance of this is explored in terms of the production sequence, logistics and supply‐chain management involved in the construction of this enormous funerary assemblage. Of particular interest is a compositional distinction between figures marked with the names ‘Gong’ (宫) and ‘Xianyang’ (咸阳). These seem to represent the products of two workshops involved in the supply of ceramic objects for this ambitious, large‐scale building project undertaken by the Qin Empire during the third century bce . 相似文献
2.
14年抗战,九一八事变是毫无疑义的起点。在这历史的起点,中共是当事各方都没有忽视的重要存在。实际上,当时日本利用一切机会强调中国共产党这一因素在东北问题复杂性中的地位。当国际联盟(League of Nations)派员到东北实地考察时,日方以当地“土匪”有受共产党“策动之虞”,配置装甲车,作为国联专列的“先导”,①以作微妙的提醒。 相似文献
3.
甘肃酒泉、嘉峪关壁画墓霉菌分离鉴定与防治研究 总被引:1,自引:1,他引:0
通过对墓葬壁画霉菌分离鉴定,筛选出合适的防霉材料,对壁画进行防霉处理是解决未搬迁尚很潮湿壁画墓科学保存问题的一个重要方面。 相似文献
4.
This paper provides a new review of archaeometric research carried out on glass found in China, set in an archaeological context, from its earliest occurrence to the Song dynasty. It is set within a broad geographical context taking the terrestrial and maritime Silk Road contacts into account. We discuss chemical and isotopic compositional contrasts in glasses from different periods found in different parts of China, the glasses that were almost certainly made in China and those that were imported. A theme that runs through the paper is the problem of provenancing glass found in China, along with a lack of evidence for primary glass‐making sites and minimal evidence for secondary glass production. We discuss the glass artefacts that are of typical Chinese types and contrast these with imports; the structure reflects this contrast. We discuss potential new scientific and archaeological approaches to Chinese glass. 相似文献
5.
Solution strategies are presented to address three potential problems in the empirical derivation of fragility functions from empirical data using the maximum likelihood method. The first strategy addresses the case of fragility curves that cross, the second strategy incorporates demand uncertainty in fragility derivation from post-earthquake reconnaissance data, and the third strategy provides a framework for the resolution of conflict between empirical data and expert opinions. The advantages and disadvantages of the proposed solution strategies are discussed and their use is demonstrated by way of suitable illustrative examples. 相似文献
6.
Zbigniew M. Bochenski Teresa Tomek Krzysztof Wertz Małgorzata Kaczanowska Janusz K. Kozłowski Adamantios Sampson 《Archaeological and Anthropological Sciences》2018,10(7):1603-1615
The taphonomic analysis of avian remains from Sarakenos Cave reveals that, contrary to previous suggestions, many bird bones excavated there represent food remains of the Eagle Owls rather than humans. The conclusion is based on the presence of traces of digestion, beak and claw punctures, and indirect evidence that includes relative preservation of particular elements, species composition, the lack of cut marks, and the absence of numerous traces of burning. Specimens with medullary bone and traces of digestion indicate that the owls killed breeding females in spring. Since it is unlikely that owls shared the cave with humans at the same time, it supports the notion based on archeological evidence that human groups did not inhabit it permanently. 相似文献
7.
1866年《南部宅地法》为了解决美国黑人自由民的土地问题制定了相对有利的宅地申请条件。然而由于缺乏申请宅地以及从事农业生产的初始资本和其他借贷来源,美国联邦政府也没有在借贷方面为宅地申请者提供相应的扶持,绝大多数黑人自由民并没有利用《南部宅地法》提供的有利条件转变为独立的小农场主。这是1866年《南部宅地法》失败的深层次原因。 相似文献
8.
K. Su J.‐P. Latham D. Pavlidis J. Xiang F. Fang P. Mostaghimi J. R. Percival C. C. Pain M. D. Jackson 《Geofluids》2015,15(4):592-607
Accurate simulation of multiphase flow in fractured porous media remains a challenge. An important problem is the representation of the discontinuous or near discontinuous behaviour of saturation in real geological formations. In the classical continuum approach, a refined mesh is required at the interface between fracture and porous media to capture the steep gradients in saturation and saturation‐dependent transport properties. This dramatically increases the computational load when large numbers of fractures are present in the numerical model. A discontinuous finite element method is reported here to model flow in fractured porous media. The governing multiphase porous media flow equations are solved in the adaptive mesh computational fluid dynamics code IC‐FERST on unstructured meshes. The method is based on a mixed control volume – discontinuous finite element formulation. This is combined with the PN+1DG‐PNDG element pair, which has discontinuous (order N+1) representation for velocity and discontinuous (order N) representation for pressure. A number of test cases are used to evaluate the method's ability to model fracture flow. The first is used to verify the performance of the element pair on structured and unstructured meshes of different resolution. Multiphase flow is then modelled in a range of idealised and simple fracture patterns. Solutions with sharp saturation fronts and computational economy in terms of mesh size are illustrated. 相似文献
9.
Cheng Lei Meng Hui Zhang Shi Qiang Fang 《International Journal of Architectural Heritage》2015,9(8):942-948
Ancient mortars played a crucial role in the construction of historical architectures due to their physical and chemical compatibility with traditional building materials such as stones and bricks. Therefore, the analysis and optimization of the ancient mortar formula are significant in the restoration and preservation of historical sites. In this work, 20 mortar samples selected from five ancient stone pagodas in Zhejiang Province, China, were analyzed. The results showed that mud, lime-soil mortar, lime-sand mortar, and lime-gypsum mortar were used as binders in these pagodas. The Ca(OH)2/aggregate ratio ranging from 0.3 to 2.7 was usually used to prepare lime mortar. Protein and polysaccharide were also found in some samples. 相似文献
10.
罗马帝国初期的200年(公元前27年~公元2世纪)是罗马的鼎盛时期,开创了经济、文化、军事、艺术前所未有的高峰,被称为"罗马和平"时期。本文保护修复的几件"罗马和平"时期的石碑原本收藏在意大利罗维纳市的Lapidario博物馆,后委托意大利博洛尼亚KRITERION文物修复公司进行保护修复,进行了清洗、补全、封护等保护修复工作。 相似文献