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1.
Y. Zhang L. Wei Z. Cui T. Zhang Y. Lei A. Gu Y. Chen L. Y. Zhang Z. X. Du 《Archaeometry》2020,62(3):660-676
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
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Y. H. Dennis Wei 《Geografiska annaler. Series B, Human geography》2011,93(3):237-251
This article attempts to advance the research on industrial districts and regional development through a study of the restructuring of the clothing industry in Wenzhou Municipality, a regional driver of the Chinese economy. Wenzhou is known for the Wenzhou model of development traditionally centred on family‐owned small businesses embedded in local institutions. The clothing industry is one of the leading industries in Wenzhou, and a cluster with national significance has emerged, where most of the production components can be purchased locally. However, the industry has been scaled up nationally and internationally, with the expansion of sales networks and production facilities across China, and to a lesser extent, abroad. This restructuring has changed the endogenous nature of industrial clusters/districts. The restructuring challenges the orthodox notion of the Wenzhou model and the New Regionalism literature, particularly the orthodox notion of Marshallian industrial districts that overly emphasizes small firms and local assets, and the global production network perspective that highlights coupling with global lead firms in regional development. 相似文献
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ABSTRACT. In a simple urban model, where the only spatial distinction made is between center and suburb, we introduce a uniform distribution of preferences for land. Under a logarithmic utility function, we examine how the location and consumption decisions of individuals differ in consequence of their different preferences for land. Comparative statics indicate that the qualitative response of the city at equilibrium to changes in per capita income and transportation cost is not affected by the introduction of such heterogeneity. Possible extensions are also briefly discussed. 相似文献
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Kubo Y 《Journal of regional science》1986,26(3):579-593
"This paper examines the mechanism and extent of urban concentration using a two-sector growth model. The cause of urbanization is sought in the existence of urban scale economies. Assuming that temporary production decisions are concerned with optimal labor inputs and that profit incomes are reinvested according to relative profitability, the model shows persistent tendency for urban concentration and the transition of the economy from unlimited to limited labor supply. A simple example suggests that urban concentration is more likely than rural expansion with urban contraction." 相似文献
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针对莫高窟在保护利用数据传输过程中出现的问题与发展趋势,提出了利用无线网络深度覆盖技术构建数据传输平台,解决莫高窟大型洞窟内保护利用数据无法传输的问题。为构建实用性强的传输平台,采取了如下措施。首先,针对莫高窟保护利用各项业务数据采集、传输模式、传输机制等各阶段特点,提出了基于无线网络深度覆盖技术构建数据传输试验平台的需求;其次,设计了试验平台构建方案,依据莫高窟洞窟分布与建筑形制确定了试验平台构建位置。结合莫高窟目前无线网络覆盖现状,通过选型分析确定了无线网络深度覆盖关键技术,并应用该技术构建试验平台;最后,对试验平台无线信号覆盖范围、信号强度、传输性能、安全性等进行验证,确保数据传输的完整性与连续性。此试验平台已运行一年有余,应用效果良好。 相似文献
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