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1.
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
2.
油画颜料层裂纹是一种常见的病害类型,严重的裂纹会影响作品的视觉效果。裂纹修复所采取的措施应以缓解病害,延续寿命为目标,避免不当修复对其文物价值的改变。本研究通过红外光谱和便携式X荧光能谱分析,初步确定了裂纹产生的原因与材料技法和机械作用力有关,长期的温湿度波动则是最终形成老化裂纹的重要因素。对两类常见的裂纹加固方法比较后得出结论,色蜡改变了原画的光泽度和肌理层,动物胶调碳酸钙更适宜作为裂纹的填补材料。观察修复后的油画保存状况,发现经过修复的颜料层仍存在继续劣化的风险,必须维持保存环境的相对稳定,方可延长修复周期。 相似文献
3.
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
4.
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
史红帅 《中国历史地理论丛》2020,(1):5-24
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
5.
Cheng Lei Meng Hui Zhang Shi Qiang Fang 《International Journal of Architectural Heritage》2015,9(8):942-948
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.
Wei She M. R. Jones Yunsheng Zhang Xing Shi 《International Journal of Architectural Heritage》2015,9(7):775-793
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.
Shi Jinsong 《Acta Archaeologica》2019,90(1):81-109
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
8.
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
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10.
二里头文化二里头类型第一期和第二期是同一种文化连续发展的不同发展阶段。二里头类型主要来源于豫西南地区的河南龙山文化晚期。后羿属于东夷,而非西夷。 相似文献