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101.
高青陈庄遗址M35、M36出土的青铜器具有黑色锈蚀等特殊的腐蚀现象。本研究在对这两个墓出土青铜器腐蚀现象统计分析的基础上,对其典型的腐蚀特征进行了总结,并进行了相应的科技检测分析。得知,这两个墓葬土壤中可溶性硫酸盐的含量很高;青铜器中含有大量的S;其黑色腐蚀产物为铜硫化物;闪亮颗粒物为结晶良好的铜硫化物,晶粒为平行的板片状集合体;含有大量的“铜”,纯铜颗粒和纯铜片的显微结构形貌与铜硫化物相同;铜器所带有的绿色调和绿色锈点为硫酸盐矿物结晶所致;基体表层黄白、灰白色锈蚀中含有铜锡合金;铜器很少检测出氯离子。  相似文献   
102.
Copper ores recovered at the third millennium bce settlement of São Pedro, Portugal, were characterized by micro-Raman spectroscopy, micro-energy dispersive X-ray spectrometry (micro-EDXRF) and micro-particle-induced X-ray emission spectrometry (micro-PIXE). The collection shows the common presence of secondary copper minerals (malachite, pseudomalachite and libethenite) combined with iron oxyhydroxides (hematite and goethite), while arsenic-rich minerals are absent and, therefore, can be excluded as the source of arsenical copper. Overall, these copper ores suggest a primitive technology involving the exploitation of the superficial zone of ore bodies and reliant on the fortuitous finding of arsenic-rich sources to produce the arsenical copper alloy frequently present among metallic collections of the Iberian Peninsula.  相似文献   
103.
Over the course of the eighteenth century, two major models of European international order emerged as alternatives to universal monarchy: one was based on the balance of power; the other centred on the idea of perpetual peace. This article traces each back to its origins in debates around the moment of the Peace of Utrecht in 1713. In particular, it examines the evolution of the doctrine of balance of power in early eighteenth-century English political thought and then as a legal principle incorporated into the Treaty of Utrecht, before proceeding to the counter-proposal in the form of the Abbé de Saint-Pierre's Plan of Perpetual Peace and the objections it raised. It then shows how Saint-Pierre's paradigm of a league of European states found (albeit in altered form) its way into the Treaty of the Holy Alliance (1815) proposed by Tsar Alexander I after the defeat of Napoleon. It concludes by highlighting the fundamental soundness of the idea of European league, as well as the flaws inherent in the early model of Saint-Pierre.  相似文献   
104.
This article analyses the industrial enterprise of the Dutch-born brothers Abraham and Jakob Momma-Reenstierna and their investments in Sápmi and the upper parts of the Torne River Valley, northern Sweden, during the second half of the seventeenth century. The aim is to explore the driving forces behind the industrial projects of the two brothers in a larger global and colonial context. With inspiration from recent critical studies on the simplifications, and Eurocentrism, in earlier understandings of the birth of modernity, we focus on the modernizing processes taking place in the upper part of the Torne River Valley as a meeting zone between local populations and landscapes and external capital. Metal extraction was booming in the seventeenth-century Sámi areas. Both the Danish-Norwegian and the Swedish Crowns invested heavily in the mining of silver, copper and iron. The scientific focus in archaeology and history has hitherto been very much on the state-governed projects, and limited interest has been directed towards the private enterprises. Moreover, there is also a need to study the roles of the local Finnish and Sámi populations, as well as the global connections, in these colonial industrial projects.  相似文献   
105.
This paper highlights the geographical contributions made to academic debate about democracy, representation and the role of the political party. It argues that while geographers have made important arguments in relation to the structure and operation of representative democracy, there is scope for paying greater attention to the internal spatial dynamics of the political party. A successful political party requires a balance between the national party machine and its local membership base. This paper draws on research to explore the way in which the British Labour Party sought to renew its local membership base by adopting community organising techniques and establishing a new arms-length organisation, Movement for Change (M4C), between 2010 and 2015. It uses this research material to highlight the importance of the internal balance of power within any political party, and the need for a multi-scalar approach to understanding the successful operation of any political party.  相似文献   
106.
David Rindos' coevolution theory remains the most comprehensive application of Darwinian theory to issues of prehistoric agriculture evolution. While his theory has drawn attention, there has been a lack of subsequent development of the application of Darwinian theory to prehistoric agricultural evolution. Combining Sewall Wright's shifting balance theory of evolution with aspects of Rindos' coevolution theory provides important new insights into the processes of crop transmission between regions. Using these theories, a model is developed for the adoption and subsequent evolution of maize agriculture in the Eastern Woodlands of North America.  相似文献   
107.
河南省镇平县楸树湾的古铜矿冶遗址,是在20世纪60年代由河南省有色金属地质勘探三队发现的.1982年由镇平县人民政府公布为镇平县第一批重点文物保护单位.1996年秋由河南省文物考古研究所、南阳市文物研究所和镇平县彭雪枫纪念馆联合对该遗址进行了复查,现将调查概况报告如下.  相似文献   
108.
随着近年来地震灾害的频发,分析浮放于俑坑中的秦兵马俑在地震波影响下的运动方式是秦俑地震灾害防御研究中的首要环节。本研究利用力矩平衡的原理测量秦兵马俑的重心位置,进而初步计算得到陶俑的临界地震加速度,依据陶俑的形体特征计算出每类陶俑的抗倾倒极限地震加速度,验证了测量结果的可靠性,为制定秦俑的地震设防等级和防震保护工作提供了基础数据。  相似文献   
109.
腐蚀青铜器中纯铜晶粒形成机理的初步研究   总被引:5,自引:0,他引:5       下载免费PDF全文
本文以吴国青铜兵器的金相检测为基础,利用电子显微镜对样品中出现的纯铜晶粒进行检 测分析,从矿物转化及自然铜形成机理解释了纯铜晶粒的形成,讨论了可能形成纯铜晶粒的条件。 结果认为纯铜晶粒的析出并非是筒单的电解分解与电解析出,这个过程涉及到合金的矿化产生不 稳定的中间腐蚀产物向析出自然铜的稳定态转变,这种转化由原子在矿物质中的反应扩散完成。这 个过程相当漫长,非实验室条件所能摸拟。从矿物转化析出机理考虑,纯铜晶粒中的“李晶”结构可 解释为自然铜的双晶形态,与合金本身,加工工艺以及腐蚀产生的微小体积变化无关。  相似文献   
110.
为研究化学镀与电刷镀技术在鎏金铜器修复中的应用,使用扫描电镜、X射线衍射等测试方法对样品进行实验。结果发现在模拟补配材料的样品上镀覆效果良好,并对一件有残缺的鎏金铜器实施茬口清理、补配、化学镀、电刷镀等保护修复技术处理,完成一件器物独立配件的制备。修复后器物形态完整,外观和谐,再现了器物的美学价值。  相似文献   
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