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41.
交通区位条件是反映区域发展潜力的重要指标,分析其与空间开发强度之间的时空协同关系对揭示区域发展的动力机制具有重要启示意义。以重庆市为例,通过指数建模、回归拟合及弹性系数等方法,揭示其间互动关系。研究发现:①研究区交通区位指数处于快速跃升阶段,区域差距有所缩小,空间集聚格局基本稳定;②空间开发强度指数数值整体偏低,增速差异较大,空间集聚格局呈单集聚中心向多集聚中心演进趋势;③不同类型的交通区位指数(内部、外部和综合)与空间开发强度指数均呈显著正相关,且关联性表现出不同状态;④交通区位演化与空间开发强度互动敏感程度较高,各弹性系数空间集聚格局基本一致,但其形成机理差异较大。 相似文献
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Ofir Katz Dan Cabanes Stephen Weiner Aren M. Maeir Elisabetta Boaretto Ruth Shahack-Gross 《Journal of archaeological science》2010
A rapid phytolith extraction procedure is described, that allows phytolith concentrations and morphotype assemblages to be analyzed within hours. This procedure enables the results of these analyses to be used during an archaeological excavation, in order to better understand how plants were used. The new procedure was tested using a standard phytolith extract and two experimental phytolith-sediment blends and found to be both accurate and precise. The reliability of partial slide counting was evaluated and found to be as accurate and precise as existing phytolith quantification methods. The new extraction and counting procedures were applied to an archaeological site, Tell es-Safi/Gath, Israel. The results demonstrate how information on phytolith concentrations in sediments that are available from one day to the next, can be used during an excavation to more effectively document the local features of interest and obtain better information. 相似文献
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Weijuan Zhao Dan Zhao Qinlong Chen Bo Wu Xiang Li Jianfeng Cui Jihong Li Bo Li 《Archaeometry》2023,65(2):259-268
This article considered glazed tiles excavated from the Ming Imperial Palace site in Nanjing as the research object. Glazed tiles were selected and analyzed via vacuum porosimeter, thermal dilation (TD), X-ray diffraction (XRD), and energy dispersive X-ray fluorescence (EDXRF) to determine their physical property, firing temperature, phase composition, and chemical composition, respectively. Results show that the firing temperature of body belongs to the temperature range (of 950–1,100°C), whereas the water absorption and apparent porosity are large. The phase composition of glazed tile bodies is the same (predominantly quartz and mullite). However, some samples contain trace amounts of rutile, hematite, sodalite, and orthoclase. The firing temperature combined with the phase composition indicates that the raw material and firing process of glazed tile body samples have similarities, which embody of the strict and unified management system of the official kiln. The raw materials of glazed tile body in the Ming Imperial Palace site may come from Dangtu glazed kiln, whereas the rest of the samples remains to be explored. This study provides a scientific basis for understanding the evolution of glazed tile-making technology in ancient China, and is important for the protection and repair of glazed buildings in the Ming Dynasty. 相似文献
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风化盐析是影响土遗址最为严重的病害之一。了解不同深度处土遗址可溶盐的含量以及变化规律可为土遗址的盐析病害提供理论依据和技术支撑。为此,本实验采用有机玻璃土柱装置和应用EM50传感器探头监测土柱不同深度处的含水率、电导率的变化规律,并结合实验室分析测定了不同时间土柱表面的含盐种类以及含盐量、不同深度处的含盐量等。结果表明,不同深度处土样的含水率越小电导率越大,且土壤表面的含水率最小,电导率最大;利用离子色谱法测定结果表明,除K+之外,Na~+,Mg~(2+),Ca~(2+),Cl-and SO_4~(2-)的含量随深度的变化趋势与含盐量随深度的变化趋势一致。本研究可为土遗址盐析病害的防治提供理论参考。 相似文献
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新石器时代对于儿童的埋葬方式在一定程度上反映出先民精神文化面貌。屈家岭文化是长江中游的一种考古学文化,在所发现的众多的遗址中,对于儿童的埋葬方式主要采取两种:一种是土坑葬,另一种就是较为多见的瓮棺葬。选取一些典型的文化遗址,分不同的类型从埋葬方式、葬具、葬坑等方面入手,进行深入的分析和研究,探讨其内涵和意义。 相似文献
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Dan Klooster 《Development and change》2000,31(1):281-305
Community forestry is thought to diffuse the kind of tensions over access to resources that frequently make centralized forest management systems based on the principles of scientific forestry ineffective and conflictive. Centralized systems often create resistance, as communities whose vegetation management practices have been declared illegal by forest bureaucracies anonymously contest the restrictions imposed on them by ‘stealing’ trees and committing ‘arson’. These restrictions are intimately related to the requirements of scientific forestry, however, so co‐management strategies relying on scientific forestry might also engender various forms of internal resistance, such as tree theft. Local interpretations of justice in access to resources, together with community social structures and the distribution of resources can result in internalized resistance, rendering community‐based resource management ineffective. In a Mexican community case‐study, scientific forestry and tree theft co‐evolved during a period of concessions and continue under co‐management. This system creates an arena where anonymous individual resistance like tree theft can give way to forms of protest more likely to result in legitimate and effective forest management systems. 相似文献