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The child-friendly city advocates for children's ‘right to the city’. Much of this advocacy focuses on the independent child, with little attention paid to the accompanied experiences of younger children, such as those travelling in prams. This paper draws on a material feminist perspective to help address this gap. We offer the concept of mother–child–pram assemblage to bring to the fore the corporeal dimensions of everyday pram journeys. By analysing sensory ethnographic materials collected with mothers and young children living in Wollongong, Australia, this paper highlights how the ‘affective affordances’ and ‘affective atmospheres’ of pram mobilities shape urban experience by reference to how motherhood and childhood are achieved on-the-move. We conclude with policy-relevant insights for the child-friendly city.  相似文献   
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There is considerable literature suggesting that silica (opal) phytoliths cause dental enamel microwear in mammals. Much of this literature cites a single study from 1959 as evidence that silica phytoliths are harder than mammalian tooth enamel and so have the potential to cause dental microwear. No other studies using similar methodology have actually confirmed whether phytoliths are harder than dental enamel.  相似文献   
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Traditions and transitions in Korean bronze technology   总被引:1,自引:0,他引:1  
Metallurgical examination of Korean bronze artifacts shows that a technical tradition based on casting and use of leaded high-tin alloys was established in Korea at the early stages of bronze use. After the subsequent discovery of quenching methods that suppress formation of the brittle δ phase, new thermo-mechanical techniques were introduced between the 7th and 10th centuries AD. Lead-free alloys were used, and tin contents near that of the peritectic point in the Cu–Sn phase diagram were chosen. Leaded high tin alloys continued in use, but only in cast objects, and with significant composition variation. The unique conditions during the time of innovation suggest that the transition to new metallurgical techniques was gradually achieved through domestic technical innovation inspired by external influences.  相似文献   
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Metallurgical study of seven cast iron artifacts recovered from sites of the former Xiongnu (BC 3rd to AD 1st), Turk (AD 6th to 8th), Khitan (AD 10th to 12th), and Mongolian empires (AD 12th to 15th) shows that the earlier Xiongnu and Turk artifacts were made of cast iron alloys of near eutectic composition. The later Khitan and Mongol objects had greatly reduced carbon content in the range of ultrahigh carbon steel rather than cast iron, and contained more than 0.5 mass % silicon as an alloying element. Inclusions high in sulfur, phosphorus or silicon are also present. These differences suggest that Mongolia experienced a technical transition a few centuries before the establishment of the Mongolian empire, which is in agreement with some written accounts. The microstructures of the cast iron artifacts are compared with the related archaeological and documentary evidence. The results suggest that the use of fossil coal in smelting and the state policy of controlling iron production were the major factors responsible for the transition.  相似文献   
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In September 1988 archaeologists and students from the Program in Maritime History and Underwater Research at East Carolina University (PMHUR) identified the remains of an early shipwreck during a survey of the Western Ledge Reefs carried out for the Bermuda Maritime Museum (BMM). Structural material exposed at the wreck site proved to be a section of lower hull containing the keel, hull planking, frames, and a portion of the keelson that included a mast-step. In order to recover the archaeological record preserved at the site, the BMM applied for, and received, a licence from the Receiver of Wreck. As work at the site intensified, a prior claim to the wreck was discovered. Discovery of that claim ultimately led to a co-operative agreement between Brian Malpas, Donald Canton and the BMM that permitted on-site investigation to continue. During 1989 and 1990, the site was excavated by the Museum's underwater archaeological staff, the staffand students of the PMHUR and volunteers. In 1990, a comprehensive in situ map of the hull remains was completed and in accordance with the terms of an agreement between Malpas and Canton and the BMM, a team of archaeologists, students and volunteers raised the remains of the Western Ledge shipwreck in August 1991. Each recovered element of the wreck was transported to storage facilities at the museum and catalogued, cleaned, recorded and documented using techniques developed to record the Red Bay galleon. That work was completed in the autumn of 1991 and on 31st October 1991 the wreck structure was donated to the museum for study and possible display.  相似文献   
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