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排序方式: 共有3343条查询结果,搜索用时 15 毫秒
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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元末熊梦祥所撰《析津志》(现仅存辑佚本)的"名宦"部分,从木华黎到刘因等47人的记载,是从《元朝名臣事略》中辑录而得,二者之间存在史源关系。确立了史源关系后,进一步梳理其中的内容,发现《析津志》和《元朝名臣事略》对元初中书官员刘肃的官职记载亦有误,应为"左三部尚书"而非"右三部尚书"。深入考察后进一步发现,《元史·百官志》对元初左右三部设置时间的记载亦有误,应为中统二年,而非中统元年。 相似文献
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ABSTRACT This paper investigates the implication of production-technology uncertainty for the exclusion theorem. The paper presents the result that the risk-averse firm facing production technology uncertainty prefers an intermediate location to avoid risk under certain conditions. The firm chooses an intermediate location (over a corner location) particularly if its degree of risk aversion overwhelms the inherent convexity of profit with respect to location. The latter depends, in turn, on the structure of production technology characterized by the elasticity of substitution and returns to scale parameters. 相似文献
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Geoffrey K. Turnbull 《Journal of regional science》1988,28(4):541-562
ABSTRACT. This paper incorporates an exogenous taxing and service-providing public sector into a dynamic residential land-use model in order to examine how local-government fiscal policies alter the pace and pattern of residential development. The model is used to derive the comparative-dynamic responses to variations in the income, sales, and property taxes and public-service time paths. The results show how tax and expenditure effects systematically depend upon the anticipated relative growth rates in rents to alternative uses and vary across locations within a given urban area as well as across urban areas themselves. 相似文献
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ABSTRACT. This paper introduces the household interactive variable input-output (HIVIO) model to measure the effect of cost variation on industrial outputs. The model produces a variety of cost elasticities that separate out impacts on industrial prices, imports, and outputs, with “own” and “cross” elasticity components. Like the conventional input-output multipliers, these cost elasticities can be useful parameters to evaluate the substituting behavior of firms and consumers. By using the 1980 Korean input-output transactions table, we find the wage and import price effects on industrial prices, outputs, and import demands. 相似文献
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Mohammed K. Fazel 《Iranian studies》1988,21(3-4):37-51