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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.
The time dimension has not attracted enough attention in policy process research in China, yet speed is the most distinctive feature of China’s recent development. This article, based on observations of China’s policy practices, proposes a new research perspective for understanding how the Chinese government has been able to address policy challenges in an era of rapid transition. The approach adopted by the government allows decision makers to respond quickly to serious problems with a truncated decision-making process, and then implement the decisions through a more gradual deliberative process. The article examines China’s coal-mining industry reform as an empirical case to illustrate how this governance approach has been used to achieve major policy reform, namely property rights reform for coal mines, while simultaneously maintaining stability, regulating production safety, and stimulating industrial development. The article concludes with a discussion of the broad implications of this pattern for improving the effectiveness of public policy both in and outside China.  相似文献   
3.
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   
4.
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   
5.
In archaeology, strontium isotope analysis is developing into an efficient scientific technique for tracing the movement of prehistoric humans and animals. Determining the local bioavailable 87Sr/86Sr ratio range is the key to distinguishing whether the human or animal is indigenous to the local area. It has been shown that the 87Sr/86Sr ratio in the enamel of pigs can be an excellent sample to determine the range of local strontium isotope ratio at the site. However, pigs may not be all local at the site, and there is no special study on whether pigs’ different ages and tooth types impact the local strontium isotope characteristics. In this paper, the tooth enamel of 19 pigs from the Zaoshugounao site for strontium isotope ratio (87Sr/86Sr) by multicollector–inductively coupled plasma mass spectrometry. There were no significant differences in 87Sr/86Sr ratios of local pigs at different months and different molar types, which did not affect the determination of the local strontium isotope standard. Based on the local strontium isotope ratio range (0.711056–0.711476), we found that five pigs were non-local. The Jing and Wei river basins (in Guanzhong basin) and northern Shaanxi are likely sources of non-pigs.  相似文献   
6.
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   
7.
Lei, Q.P., September .2015. New ontogenetic information on Duyunaspis duyunensis Zhang & Qian in Zhou et al., 1977 (Trilobita, Corynexochida) from the Cambrian and its possible sexual dimorphism. Alcheringa 40, XXX–XXX. ISSN 0311-5518.

The hypostomal condition and the complete ontogenetic development of Duyunaspis duyunensis Zhang & Qian in Zhou et al., 1977 are restudied on the basis of abundant specimens from the Balang Formation (Cambrian, Qiandongian) in Zila Village, Paiwu Township, Huayuan County, Hunan Province. The relatively complete ontogenetic series (degree 0 to 9) provides new evidence that the holaspis of this species has nine rather than seven thoracic segments as proposed by McNamara et al. (2006). Comparisons between Duyunaspis duyunensis and two associated species, Arthricocephalus chauveaui and Changaspis elongata, support its placement in the Subfamily Oryctocarinae. Moreover, based on observations of a large number of specimens, the presence of an anterior indentation on the pygidial end is possibly representative of sexual dimorphism.

Qianping Lei [], Natural Department, Changzhou Museum, Changzhou, Jiangsu Province, 213022, PR China; State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, 210008, PR China.  相似文献   

8.
蔡磊 《民俗研究》2007,(1):55-262
2006年12月16日至17日,"民族志·民俗志的理论与实践学术研讨会"在北京师范大学成功召开.这次大会由北京师范大学文学院民俗学与文化人类学研究所、北京师范大学民俗文化普查与研究中心、北京民间文艺家协会联合主办.  相似文献   
9.
陕西省麟游县境内以山地为主,山丘之间河溪众多,西北部的天堂河乃泾河水三级支流,其北流注入达溪河。天堂河与其支流南沟交汇处即园子坪遗址之所在(图一)。  相似文献   
10.
《冠子》中的《夜行》篇主要讲述了道家的某些思想。所谓“夜行”即《管子》的《形势》篇中所言的“心行” ,具体而言 ,就是于内心行道 ,不待见于具体行事 ,已能达到招远亲近而有天下的效果。  相似文献   
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