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991.
The petrography as well as the major and trace element compositions of the Selinunte grinding stones, made of grey vesicular lava, were analysed. By comparison with geochemical data from volcanic rocks in the Mediterranean, we were able to determine that only a minor number of the tools were extracted from the nearest volcanics of Mount Etna and the Hyblean Mountains, while the majority of the grinding stones were most probably imported from the Aeolian Islands, although an origin from the Aegean cannot be excluded entirely. The results are important in order to scrutinize trading connections, especially for the earlier times of settlement during the sixth century bc .  相似文献   
992.
Archaeological wood is usually severely degraded. The Norwegian Viking Age Oseberg find exemplifies problems arising due to past conservation treatments and the need for new types of preservatives. Phenol formaldehyde (PF) has been investigated as a consolidant for alum‐treated wood. X‐ray tomography has revealed that it is possible to obtain a porous structure inside the wood, ensuring ethical acceptability by allowing re‐treatment. In order to understand the curing mechanics, the kinetics of the initial condensation reaction were elucidated at room temperature. It was found that a second‐order reaction using both phenol and formaldehyde concentrations is the most probable mechanism.  相似文献   
993.
Xiaoshan in Zhejiang Province was an important ceramic production area in ancient China. During recent years, local archaeologists have found a number of mound tombs dating to the Zhou Dynasty and the Spring and Autumn period. Many shards of stamped stoneware and proto‐porcelain have been unearthed from these tombs. In this paper, we report how we collected ceramic shards from tombs and samples from local ancient kilns as reference materials in order to clarify their relationship. We have used the energy‐dispersive X‐ray fluorescence technique to analyse the chemical composition of the ceramic samples. The results indicate that some of the tomb artefacts may be imported from other production areas. We infer that the other tomb samples were produced at local kilns, but due to production process–related compositional differences, there are small differences in chemical composition between different categories of samples.  相似文献   
994.
Stable isotopic analysis was undertaken for the gunpowder ingredients from crude saltpetre and propellants from several types of gun that prevailed during the late 19th century in south‐western Japan. Stable isotopic signatures for δ15Nsaltpetre nitrogen, δ34Snative sulphur and δ13Ccharcoal carbon in crude saltpetre, gunpowder magazines bearing the trademark of mills from southern Scotland and cartridges for an improved Sharps rifle (with a US trademark) all imply common assemblages from the same source (saltpetre and native sulphur from British India and Sicily, respectively) in the United Kingdom (UK). One Pritchett patron is common for muzzle‐loading Enfield rifles, while the other suggests a four‐allied lead bullet for an unidentified hand gun. Propellants in the Pritchett patron from the same institution also suggest a common source of these rifles. On the contrary, the ingredients for an unidentified rifle and time fuse for a Paixhans gun with unique stylistic devices showed distinctive isotopic signatures, indicating a local Japanese origin. The Pritchett patron from the Kumamoto Museum involved a mixed provenance from the UK and Japan. The stable isotopic analysis provides direct evidence for the ultimate origin of the propellant.  相似文献   
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Justin T. Maher 《对极》2015,47(4):980-998
Complicating top‐down analyses of neoliberal development, this article charts how demographically diverse residents in Columbia Heights—a rapidly gentrifying neighborhood in Washington, DC—reinforce and resist dominant narratives of diversity that praise multicultural, mixed urban spaces. These narratives often not only fail to discuss power and equity, they are typically used to market state‐sponsored, upscale development that actively threatens the very diversity appropriated to sell a neighborhood. I argue that many residents initially reproduce this rhetoric of diversity, but discuss power and difference more candidly in their discussion of the neighborhood's history and amenities. Most residents who recently moved to the neighborhood juxtapose praise of diversity with comments that associate crime, litter, and “grime” with that diversity. Residents who grew up in Columbia Heights moved from praising the influx of development and new (largely upper‐middle class) residents to expressing concerns about exclusion, disrespect, and possible displacement.  相似文献   
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