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1.
Palace lanterns were important and highly visible decorations in the imperial palace in Beijing, China, during the Qing dynasty (1636–1912). Most lanterns had colourful tassels made of fibres. The study performed a comprehensive investigation of the materials and dyes used for palace lantern tassels preserved in The Palace Museum, Beijing. Eight samples with different colours, including yellow, green and red, from five palace lanterns were analysed. By using ultra-performance liquid chromatography combined with time-of-flight mass spectrometry, the compositions of the dyes were identified quickly, and thus the dyes' origins were explored. A X-ray fluorescence spectrometer assisted in the detection of whether a mordant was used during the dyeing process. As a result, the tassels were all made of silk, discovered through the use of microscopic observation and micro-Fourier transform infrared spectrometry analysis. Different dyeing techniques were found in these tassels: yellow tassels were dyed by cork tree or turmeric by a direct dyeing method; greens were dyed by pagoda bud with an iron mordant, or by the combination of cork tree and indigo using multi-dyeing method; and red tassels were coloured with different acid red industrial dyes. These results provide valuable data for the conservation of ancient textile tassels and contribute to the investigation of other hanging tags.  相似文献   
2.
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   
3.
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   
4.
利用三维扫描技术获取兵马俑残片的三维点云数据,结合Geomagic Studio和Hypermesh建立高精度的兵马俑足踝残片三维实体网格模型。通过基于ABAQUS的重力作用下的有限元分析,研究足踝部分的Von Mises应力和变形特征,以确定足踝处的受力薄弱部位。为进一步探究模型各残片的最佳点云简化比例,采用点云简化模型进行相同工况的有限元分析,以验证点云简化的可靠性。结果表明:结构在重力作用下可保持安全稳定的状态,相对薄弱部位位于左腿足踝处;对于大部分残片,其最佳简化比例在60%~70%,简化后可有效缩短模型实体化处理时间;采用简化模型得到的有限元结果,其最大Mises应力相比于原始模型的误差小于15%,且应力云图和变形图形状接近,模型简化具有可靠性。  相似文献   
5.
聚醋酸乙烯酯(PVAc)乳液是常见的彩绘类文物保护材料。采用激光粒度仪、热重/差热分析、红外光谱、X-射线衍射、扫描电镜、透射电镜等表征了PVAc乳液的粒径以及胶膜的热稳定性、结构和形貌;采用粘度计、表面张力仪、pH计、电导率仪等研究了乳液浓度与其粘度、表面张力、pH、电导率的关系;通过冻融、室温-高温放置、离心分离研究了乳液的稳定性;同时用PVAc乳液对模拟起甲和酥碱的壁画进行了修复。结果表明,PVAc乳液粒径呈双峰分布,小粒子的平均粒径为380 nm,大粒子的平均粒径为5.85μm;乳液胶膜为非结晶物质,胶膜热重的最终质量残留为1.54%,335℃出现放热峰。PVAc乳液的电导率随浓度的增大而增大,pH随浓度的增大而下降;相同温度下表面张力随浓度的增大而基本呈现低浓度下降,高浓度上升的趋势。相同浓度下,表面张力随温度升高而无显著变化,表明PVAc乳液的表面张力受温度变化影响不大。相同温度下,乳液粘度随浓度的增大而增大;相同浓度下,乳液的粘度随温度的升高而降低。冻融、离心分离和不同温度下静置发现,该乳液出现分层。用该乳液对模拟起甲和酥碱壁画修复后,再分别老化20个循环和12个循环,发现颜料层再次空鼓、起甲。综合分析,说明实验中所使用的该种PVAc稳定性和抗老化能力较弱,在修复彩绘类文物中应慎重选择PVAc的种类,综合考虑PVAc的使用浓度、环境因素对其性能的影响,以达到最佳使用效果。  相似文献   
6.
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   
7.
J. Henderson  J. An  H. Ma 《Archaeometry》2018,60(1):88-104
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   
8.
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   
9.
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   
10.
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   
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