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1.
展翔 《文献》2021,(1):32-51,F0003
中国国家图书馆所藏甲骨数量极为丰富,《甲骨文合集》和《甲骨文合集补编》仅收录其中部分藏品的拓片。本文以"中国国家数字图书馆·拓片数据库·甲骨拓片"业已公布的甲骨拓片和彩照为研究对象,进行著录整理。具体包括甲骨残片缀合15组、复原13组,并对742版甲骨做出著录情况的对勘。  相似文献   
2.
古铜矿遗址围岩表层有害生物的防治   总被引:3,自引:0,他引:3  
铜绿山古铜矿遗址地处长江中游地区、空气湿度大、围岩表层有害生物成片生长蔓延,对遗址的长期保护造成极大威胁。对此采取了改变遗址的环境条件、喷涂消杀药品的方法,消除了围岩表层有害生物的危害。经过一年半的观察表明该方法是可行的。  相似文献   
3.
近70年来中国历史城市地理研究进展   总被引:1,自引:0,他引:1  
历史城市地理是历史地理学的重要分支之一。近70年来,中国历史城市地理研究经历了奠基与探索、缓滞、复苏与拓展、深化与融合等发展阶段,在研究内容拓展、理论与方法总结、新技术探索等方面取得了长足进步和丰硕成果,促进了中国历史地理学的整体发展。基于近70年来历史城市地理领域的代表性研究论著,总结了中国历史城市地理研究的阶段性特征,论述了九大专题领域的研究进展,并对历史城市地理研究相关问题进行了辨析,对今后的研究趋向加以展望。  相似文献   
4.
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   
5.
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   
6.
The Hui-style residence is an important architectural heritage of China. The hollow wall structures are widely used to build its exterior wall system. However, the thermal performance of the hollow wall is no longer able to meet the new energy-saving and environmental requirement. This article describes a laboratory study of the development of foamed mortar (FM), with the potential for use in thermal upgrading of the Hui-style hollow wall system without dramatically changing its traditional structure. The key early age, physical, mechanical and thermal properties were systematically measured. Two extended models were respectively developed to calculate compressive strength and thermal conductivity, as a function of porosity. Environment chamber test was also employed to investigate the effectiveness of this novel thermal upgrading approach and the results show that filling the voids with FM can effectively improve the overall thermal resistance of the hollow wall system by 44%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system. In addition, the combination of these two methods yielded an overall thermal resistance of 0.701 m2·K/W, which is even higher than 0.67 m2·K/W for the code required in the hot summer/cold winter climate zone.  相似文献   
7.
Kicking in soccer has been the subject of scientific research for more than 40 years yet review articles summarizing the biomechanical fundamentals of kick optimization as a guide to coaching are scarcely to be found. The current review article aims to bridge the gap between scientific research into the maximal instep kick (including studies employing 3D motion capture and full-body biomechanical modelling) and the application of such research in coaching. It does so by supplying a scientifically founded, coaching-friendly article explaining identifiable characteristics and motor control sequencing that define this skill. Relevant biomechanical factors are identified in a way that should help coaches better develop training programmes and, at the same time, foster better understanding of the skill among athletes. Such information will contribute to both accelerated skill acquisition and, by concomitant gains in skill efficiency, the development of programmes that minimize risk of injury to athletes during training.  相似文献   
8.
The Chinese Bronze Age culture from the 19th to the 1st century BC can be divided into four zones: the Central Plain in the middle and the lower Yellow River region; the Northern zone along the Great Wall; the Southern zone, south to the middle and the lower Yangzi River; the Southwestern zone covering the upper Yangzi River. In each zone, bronzes are not only different in types and styles but also function differently responding to the processes of the early state formation and social development. More precisely, in the first zone, there are mainly ritual bronzes, serving as symbols of the social and political hierarchy. In the second zone, there are mainly utilitarian items such as weapons, tools, bronzes of everyday use, ornaments, as well as horse‐chariot fittings. Bronze musical instruments characterise the third zone. And bronzes of the fourth zone are realistic or symbolic in style, depicting scenes of social life. Though having different cultural origins and characteristics, the four zones communicate with and influence each other continuously, creating a dynamic cultural landscape of the Chinese Bronze Age.  相似文献   
9.
本文论述清代帝陵中的哑巴院和月牙城的建置与功用,进而探讨其规制的起源问题。指出关外的福陵与昭陵系参照北京明代后期的帝陵及清孝陵兴建,而南京明孝陵的规制已见哑巴院的雏形,其发展演变脉络清晰,故而哑巴院和月牙城并非明清两代帝陵规制最显著的差别。  相似文献   
10.
施爱东:做民间文化研究,许多人都把自己弄得很"田野",但我注意到您却非常注重仪表和礼节。只要是开会或上课,您总是西装革履地出现在公共场合,这样严谨地生活累不累?您参加我的博士后出站报告会的那一天,因为来不及回家换衣服,居然临时跑到商店买了一件正式的衣服换上了,那件事给我的印象非常深刻。  相似文献   
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