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ABSTRACT

Instead of the framework of influence–acceptance commonly used in previous studies, the author uses new sources to reexamine John Dewey’s visit to China from the perspective of interactive experience. This study presents Dewey’s lectures in China as the result of interrelationships among a variety of elements – Columbia University, different hosts and audiences, the media, all levels of the Chinese government, the domestic situation in the United States, the international situation, and Dewey’s expectations and work – against the general background of China’s New Culture Movement and new educational reforms. Dewey’s speeches on democracy, science, and new education were remarkably successful in the first year of his visit to China, but began to meet with resistance from some students beginning in June 1920. Because of the Red Scare in the United States, Dewey had to stay in China. In the second year of his visit, he gave warmly welcomed lectures on the same topics in Jiangxi, Fujian, and Guangdong Provinces. With a deeper understanding of China, Dewey not only identified himself with reform plans but also began to pay more attention to China’s economic problems. His inquiry into the problems confronting China is a good example of what he advocated in his lectures: seeing democracy, science, and new education as a way of thinking and carrying out actions and making intellectual choices while moving forward.  相似文献   
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The refining of silver ores in New Spain was defined by the chemical nature of the silver ore. Argentiferous galena (lead sulphide) could only be refined by smelting (36% silver produced), irrespective of silver content, and amalgamation (64%) could only be applied to the silver sulphide ores. Both processes were transferred from Europe, but amalgamation was transformed by local expertise from a recipe of limited application to an industrial-scale solution for refining sulphidic silver ores. Its implementation shaped the environmental history of colonial silver refining in the New World. Mercury was consumed mainly through its chemical conversion into calomel, with minimal emissions of volatile mercury. Waste silt and liquid mercury in the soil and waterways were its main legacy. Smelting created a greater impact on the environment of New Spain, via lead in lead fumes as the main heavy metal issued to the air, and its depletion of woodlands. This article argues that a technical analysis of period refining practices in New Spain reorients our understanding of Spain’s imperial relations with its New World colonies, of the role of local knowledge in a global economy of silver production, and of environmental issues in colonial history. It thus speaks to the problem of unpacking the complex web of relations that composed early European imperialism, in which were enmeshed commodities such as silver, cotton and sugar.  相似文献   
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近年来,红色旅游发展为江苏省旅游发展带来了新的机遇,也对市场经济条件下的文物保护事业提出了新的挑战。从分析江苏省红色旅游与文物保护的现状入手,通过问卷调查、现场访谈等方式进行实证研究,提出了红色旅游与文物保护的互动发展模式,并在此基础上提出了具有可操作性的发展对策。  相似文献   
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五千年前陶质建材的测试研究   总被引:1,自引:0,他引:1  
迄今为止的考古发掘表明,我国最早的陶质建材,应该是距今5500年左右的凌家滩“红陶块”。考古学家推测其原料为粘土矿物,烧成温度约800~1000℃,且其物理性能与砖质建材较为接近,应为“砖的雏形”,为此,本工作测试分析了凌家滩“红陶块”的物相组成、烧成温度、吸水率与抗压强度,同时对比分析了明砖、汉砖、现代砖的物理性能,发现“红陶块”系粘土原料在950℃以上温度烧制而成,其吸水率和抗压强度由外向内呈梯度变化,内层的抗压强度、吸水率接近于现代砖和汉砖,业已超过明砖样品,所有这些分析结果,皆支持考古学家关于凌家滩“红陶块”为砖的雏型的推测。  相似文献   
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Twenty‐six samples from domestic assemblages of 9th–12th century Córdoba were subjected to electron microprobe analysis. The results reveal two main compositional types. The first, encountered in 13 of the samples, seems to result from the combination of plant ashes with high‐impurity sand, and has some contemporary parallels from Syria and Egypt. The second type is a lead–soda–silica glass, encountered in a relatively high proportion of the glasses (11 of the 26 sampled), possibly formed by the addition of lead metal to existing glasses and with very few known parallels. These are among a very small number of results available to date on the chemical composition of glasses from medieval Spain, and the presence of a high proportion of lead–soda–silica glasses is particularly interesting, possibly indicating a technological practice unique to, or originating in, the western Muslim world.  相似文献   
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At the hill of Agios Symeon, on the island of Kea, Aegean Sea, Greece, ancient metallurgical slags with a high Pb–Zn–Cu content have been found. Thermodynamic simulations have been carried out, using the FactSage? thermodynamic database computing system, with a view to understanding the ancient metallurgical processes that produced the observed slag compositions and morphologies. The simulations demonstrate that the slag samples resulted from Cu‐making processes. It would thus appear that mixed ores were used, containing Cu2S–FeS–PbS with significant amounts of sphalerite (ZnS) as impurity. The roasted ores were reduced at relatively high oxygen potentials at ~1125°C to form Cu containing low levels of Pb, Fe and Zn.  相似文献   
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The first part of this paper is a brief critical history of the use of Pb isotopes for inferring the geological provenance of archaeological materials, with an emphasis on non-ferrous metals. The second part examines variation in the Pb isotopic ratios of oxide and sulphide ore minerals in selected regions of the world, and relates these to the geological histories of ore formation in each region. This exercise shows that in regions where most ore deposits are of similar geological age—as in the Andes, Europe and the circum-Mediterranean—provenance analysis with Pb isotopes is inherently difficult because geographically distant sources often exhibit similar isotopic ratios. Conversely, regions with many periods of ore formation—such as southern Africa—appear to be very promising regions for future studies of provenance with Pb isotopes. The wider implication of this exploratory survey is that archaeologists should carefully consider the range and clustering of geological Pb isotopic ratios in their regions of interest before investing large sums of money into Pb isotopic analysis of artefacts.  相似文献   
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年画是中国特有的民间艺术形式。本研究介绍了传统年画印制所用红蓝色料的发展历史,选取15种中国古代与近现代常用红蓝色料进行红外光谱分析,并归纳总结了标准样品的化学结构与红外谱图特征。在此基础上,利用衰减全反射傅里叶变换红外光谱仪对三幅清末民初时期的传统年画开展无损检测。结果显示三幅年画的红蓝色料均为合成颜料或染料,包括酸性大红G、酸性墨水蓝G、普鲁士蓝等。本研究扩展了红外光谱在书画文物分析检测中的应用范围,为传统年画色料的无损鉴定提供科学依据。  相似文献   
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