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71.
    
A coated Roman iron coin from Villa Loig in Salzburg, Austria was investigated. The coating is a copper alloy consisting of Cu, Pb, Sn, Zn and negligible amounts of Ag, a variant of gunmetal known as ‘leaded red brass’. The numismatic term for such a coin is subferratus (Latin). From an archaeometallurgical point of view, information about the chemical composition, the microstructure and the manufacturing technique are of interest. To achieve these objectives, different analytical techniques and metallographic examinations were applied. Droplet‐shaped iron inclusions were observed in the red brass coating, while at the grain boundaries, inside the iron core, copper and lead were detected (liquid metal embrittlement). The dendritic microstructure of the coating, the spheroidal‐shaped iron inclusions in the coating and the liquid metal embrittlement show that the iron coin was plated by immersing it in a molten copper alloy. The iron core is a low‐carbon steel with slag stringers, both of which are characteristic of a bloomery iron. Deformation twins (Neumann lines) were observed in the microstructure of the iron core and indicate that the coining was performed after the flan was cooled.  相似文献   
72.
    
This article argues that George Savile's thought casts light on international relations in the seventeenth century. Halifax's life and works concern not only England's domestic politics, but also its foreign affairs. Indeed, he develops a clear vision of international politics. This article analyses Halifax's international thought, in particular three concepts that are closely related to one another: ‘interest’, ‘reason of state’, and ‘balance of power’. Through the study of these ideas, this article will try to point out both the novelty of Halifax's thought compared with that of his contemporaries, and to reverse the stereotypical understanding of his intellectual legacy and political behaviour. The ‘trimmer’ contrasts with Louis XIV's attempt to establish a universal monarchy across Europe, outlining a doctrine of moderation that seeks to ensure liberty, security, and restraint in international relations.  相似文献   
73.
    
This paper explores the possible provenance of ores employed for metallurgical production during the Early Bronze Age in the central Hexi Corridor of north-west China. In total, 78 pieces of copper (Cu) ore samples were collected from five Early Bronze Age sites and one Cu deposit site (the Beishantang Cu deposit) in the Heihe River region of the central corridor. These sites were dated to the late Machang (4100–4000 bp ), Xichengyi (4000–3700 bp ), Qijia (4000–3600 bp ) and Siba (3700–3400 bp ) cultures. After comparing with published lead (Pb) isotopic data from other possible Cu deposits in north-west China, the results show that the Cu ores collected from the Early Bronze Age sites were most likely derived from the adjacent Beishan Cu deposit. More intriguingly, for the first time in Hexi Corridor, a dozen Cu ores were discovered containing highly radiogenic Pb. Though fundamentally different from those in the Central Plains, they illustrate a possible new type of Cu used in Bronze Age western China, and the first-hand materials are significant for further understanding the provenance of raw metals for metallurgical production in the prehistoric Hexi Corridor.  相似文献   
74.
    
The paper focuses on ceramic vessels unearthed from Copper Age necropolises located in the area of the modern city of Rome and commonly attributed to the Rinaldone culture. The peculiar vessels' shapes, mainly associated with the consumption of beverages, their accuracy of manufacture and the very low impact of these ceramic morphologies in the coeval household assemblages lead to the study of such an apparently selected production through a multidisciplinary research. Petrographic analysis, X-ray fluorescence (XRF) and X-ray diffraction (XRD) integrated with the analysis of manufacturing traces and X-ray investigation suggest the transmission of technological choices, which remained unchanged over almost two millennia.  相似文献   
75.
    
Tinning copper and copper alloy objects by putting them into (electrical) contact with metallic tin in a boiling aqueous solution of potassium hydrogen tartar is a very old technique, but is nowadays almost forgotten. It was possibly invented by the Gauls and used intensively until the 20th century. This paper first briefly recounts the history of this galvanic process. To understand better the parameters influencing the thickness of the coat and thus to reconstruct this ancient technique, laboratory tests were undertaken by varying a series of parameters. The results are then presented with a short interpretation.  相似文献   
76.
77.
清康熙年间意大利传教士马国贤及避暑山庄铜版画   总被引:1,自引:0,他引:1  
传教士马国贤是清康熙年间中西文化交流中的重要人物,是中国园林西传的先驱人物。他曾在中国宫廷服务13年,将西方的铜版技术传入中国,为康熙皇帝制作了避暑山庄铜版画。后来,他把避署山庄铜版画带回欧洲,使中国园林的图像资料第一次进入欧洲并在欧洲传播,推动了欧洲特别是英国园林设计的革命。  相似文献   
78.
先秦马车在构造技术上力求解决车辆重心的平衡与协调,尤其是为促进牵引力与重心力之间的平衡及保持重心的稳定而发展起来的构造与组装技术,进一步提高了车辆的各项性能,技术的进步使得马车各部分构件及整体形制渐趋合理。  相似文献   
79.
Studies of home-based telework by women yield mixed results regarding the usefulness of telework in facilitating work–life balance. Most research on the social impacts of home-based telework focuses on workers—employees or self-employed—who deliberately choose that alternative work arrangement. Labour force analysts, however, predict an increase in employer-initiated teleworking. As a case study of the workforce of one large, financial-sector firm in Canada, this article considers the conditions of employment of involuntary teleworkers, those required by their employer to work full-time from a home office. In-depth interviews were co nducted with a sample of 18 female teleworkers working for the case study firm in a professional occupation. Study participants described the advantages and disadvantages of working from home, particularly with regard to spatial and social aspects of locating work in a home setting. The gendered nature of their jobs, and the caring and supportive functions they provide both through their employment and their household responsibilities are seen to support the relocation of their jobs from office to their homes. In many jurisdictions, telework is promoted as a means of giving women more flexibility to balance their paid work with their household responsibilities; the article highlights some of the contradictions involved in moving the workplace into women's homes.  相似文献   
80.
Following a right cerebral stroke, the German artist Anton Raederscheidt produced a remarkable series of self-portraits that depicted his severe visual neglect and gradual recovery. These distorted images, like those drawn by others with this disorder, inform us about lateral balance in art and why it is common in the art of cultures separated in time and space. After describing how artists in various cultures have employed lateral balance, I present Arnheim’s view that this aspect of art is the result of visual forces generated by the brain. Following a brief history of visual neglect, I present evidence that this disorder provides us with clues to the origin of the visual forces responsible for lateral balance in art. The relevant brain mechanisms control exploration of visual space by integrating orienting movements with visual spatial information. The prevalence of lateral balance in art becomes understandable when we consider that these brain mechanisms evolved to promote survival in our vertebrate ancestors. I end with a speculative neurological account of the aesthetics of lateral balance – why it is pleasing and its absence is displeasing.  相似文献   
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