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水是造成砖石质文物劣化的主要因素之一,因此探明其在文物内部的分布、运移规律是开展保护研究的重要基础。微波技术在检测材料内部的水分含量方面表现出较好前景,但在文物保护领域还未普遍应用。基于此,本研究首先介绍了微波技术的理论基础和相关仪器,并选取山西省的长春玉皇庙为对象,针对砖石材料的内部含水率开展了室内样块检测和现场墙体检测。结果表明,微波技术能够较为准确地揭示出文物内部的空间含水率分布规律,这对于研究其病害成因等具有重要作用。此外,与其他多种无损检测技术相比,微波技术检测材料含水率的优点更多,值得文物工作者进一步研究与应用。 相似文献
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正In China,legend says that animals choose different trees to inhabit.In Nagqu,situated on the northern area of the Tibet Autonomous Region,trees are nowhere to be seen,and birds often share holes underground with mice and rabbits.Nagqu means"black river"in Tibetan.The place is situated 相似文献
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试论旅游项目可行性研究的理论与实践 总被引:2,自引:0,他引:2
本文论述了旅游项目的可行性研究的特征,分析了目前可行性研究工作的常见问题,剖析了以通过审批为目的的编造可行性的主要动机。 相似文献
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Feng Li Li Wu Cheng Zhu Chaogui Zheng Wei Sun Xinhao Wang Shixun Shao Yao Zhou Tingting He Suyuan Li 《Journal of archaeological science》2013
Understanding how to live successfully within our environment is among the most pressing challenges facing contemporary society. This paper probes the problem based on comparative analysis and discusses the relationship between the spatial–temporal distribution of the Neolithic cultural sites and the geographic context in the Hanjiang River Basin in the south of Shaanxi Province, China. Archaeological studies have identified 175 Neolithic cultural sites in the study area, with a sequence of Laoguantai (14C age 8–7 ka BP), Yangshao (14C age 7–5 ka BP) and the late period of the Neolithic Age (14C age 5–4 ka BP). The total number of archaeological sites, the distribution area and the density all showed an early ascending and later descending trend, but the proportion of the number of archaeological sites in the study area to the corresponding value of the entire Shaanxi Province declined sharply. Spatially, these sites were concentrated on the terraces of the Hanjiang River and its main tributaries with an altitude of 400–800 m. Multiple data were integrated to clarify the critical effects of tectonic and geomorphologic conditions on the distribution of the Neolithic sites. Further comparisons revealed the correlation of Holocene climate change and environmental evolution with the Neolithic cultural succession in the study area that ameliorated conditions to generally promote the development of the primitive culture while degeneration coincided with the culture's transition or interruption. The discussion on the origin of the primitive culture and the temporal–spatial distribution corresponding to the regional culture differentiation sheds light on the complex and dynamic human–nature interaction system during the Neolithic Age, thus emphasising the wider field-based investigation and high-resolution reconstruction works of the palaeoclimate and palaeoenvironment in the future. 相似文献
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While recent research on temporary clusters and temporary markets has emphasized the knowledge generation processes associated with trade fairs, little is known about the knowledge exchanges that are embedded in market relations at these events. This paper uses the case of the Canton Fair in Guangzhou, the largest trade fair in China, to illustrate that such events do not operate as a single market, but that they generate multiple dynamic market configurations, which entail different flows of knowledge, goods and people. In a typical case study, four types of market configurations are identified that simultaneously develop at this event. The findings contribute to a more comprehensive understanding of the dynamics of market relations, knowledge and transactions in temporary spatial settings. 相似文献