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991.
Thirty‐three samples of window glass and five glass lumps coming from three Italian archaeological sites—the Suasa excavations (Ancona, settled from the third century bc to the fifth to sixth centuries ad ), the Roman town of Mevaniola (Forlì‐Cesena, settled from the Imperial Age up to the fourth century ad ) and Theodoric's Villa of Galeata (Forlì‐Cesena, settled from the sixth century ad onwards)—were analysed to track the changes in the chemical composition and manufacturing technology of window glass through the centuries. The aims of this study were: (1) to establish the origin of the raw materials; (2) to verify the chemical homogeneity among samples coming from different sites and/or produced using different techniques; and (3) to sort the samples into the compositional groups of ancient glass. The analysis of all the chemical variables allowed two groups to be distinguished: (a) finds from Mevaniola and Suasa; and (b) finds from Galeata. All the samples had a silica–soda–lime composition, but the analysis of minor elements—in particular, of Fe, Mn, and Ti—made it possible to split the samples into two groups, with the higher levels of these elements always found in the Galeata samples (HIMT glass). In conclusion, it can be asserted that the main differences between the samples are related to their chronology. 相似文献
992.
Natural processes are known to cause significant damage to archaeological monuments. In fact, the key to understanding the decay of building materials is the internal movement of water through the mineral matrix, which influences the distribution of chemical, physical and biological deterioration processes. Electrical resistivity tomography (ERT) was traditionally used as a surveying tool within archaeology, but a new high‐resolution technique that accurately traces the movement of moisture in building materials could provide a vital tool for understanding the decay of many archaeological monuments. This paper considers current progress, the shift of ERT from soil to rock research and the impact that this development could have on future conservation, using Hertford College (Oxford) and Neolithic rock art (Golden Gate Reserve, South Africa) as case studies. 相似文献
993.
Site F2 in the Timna Valley, Israel, is a small copper smelting site of ‘primitive’ technology, dated by its excavator to the Pottery Neolithic (sixth to fifth millennium bce ). This early date challenges the common view of the beginning of smelting technology in the Levant and has been contested by various scholars since its publication. In this study, we present results of archaeointensity experiments conducted on slag fragments from the site. The slag yielded an excellent ancient geomagnetic value (64.1 ± 1.1 μT) that, when compared to the Levantine master curve, suggests an age not older than the second millennium and most probably between the 13th and 11th centuries bce . In addition to demonstrating the applicability of geomagnetic archaeointensity experiments to independent dating of slag, we discuss the implications of the current results for the socio‐historical picture of the Timna Valley, and in particular for the way in which technological developments were previously modelled in the archaeometallurgical research on the region. 相似文献
994.
The paper reports a case study of factors attracting and retaining talented and creative workers in Halifax, Nova Scotia. All categories of workers interviewed mentioned quality of place and amenities in discussing their location preferences, but that could not fully explain their choices. For some occupations (like health research), talented people followed jobs; in other sectors (like music), talented workers migrated to a sympathetic locale with the right conditions for creative engagement; creative workers in some occupations (like those in architectural, engineering or planning consulting) were more rooted in place. The social dynamics—that is, positive and collaborative social networks within key sectors and a wider community perceived as welcoming and interesting—make this mid‐sized city attractive to talented workers. Local universities and a vibrant music scene generate a mutually reinforcing context that attracted mobile talented and creative workers to the city. Respondents noted Halifax's limited cultural diversity but did not report a perceived lack of tolerance as affecting their choices. In smaller cities, the social dynamics of place and workplace and the quality of life available may play more significant roles than tolerance in attracting and retaining talented workers, challenging a basic assumption of creative cities discourse. 相似文献
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