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1.
About 200 analyses have been made on late Roman and Sassanian silver objects using energy-dispersive X-ray fluorescence. This has shown that the main feature of the composition of the silver throughout the period and across the geographical area studied was towards high fineness (average silver percentage about 95%). Compositional differences are found between Roman and Sassanian silversmiths' products for the elements copper and lead. Much of the material analysed came from hoards, and using a statistical technique on the analytical data (Discriminant Analysis) broad compositional differences between hoards were found to emerge. The use of different compositions of silver for different joined parts of a single object are discussed.  相似文献   
2.
Shape memory alloys (SMA) can substantially improve the damping capacity and re-centering capability of elastomeric isolators. The objective of this study is to assess the seismic performance of smart lead rubber bearings (LRBs) equipped with double cross ferrous SMA wires. Hysteretic shear response of SMA wire-based LRB is determined using finite element method. The seismic response of a multispan continuous steel girder bridge isolated by SMA-LRB is evaluated. Hybrid SMA-LRB bearing exhibits a significantly lower shear strain demand (up to 46% reduction) and a higher energy dissipation capacity (up to 31% increase) compared to the LRB.  相似文献   
3.
大营子冶炼遗址位于赤峰市翁牛特旗五分地镇大营子村南侧的大山的北坡上,包含东西两区冶炼遗存。东区冶炼遗存年代较早,至迟在公元前1 400年已开始冶炼活动。铅同位素、微量元素示踪研究显示大营子冶炼遗址东西两区均使用了来自林西县大井古铜矿的多金属共生矿石,直接冶炼铜砷锡三元青铜合金。大营子冶炼遗址东区冶炼遗存的年代测定,获得了迄今为止最早的夏家店上层文化年代测定结果,为探讨辽西地区青铜时代考古学文化的演变提供了新的科学证据。  相似文献   
4.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
5.
Isotopic methods are widely used in archaeology to investigate paleodiet. Here, we present a new method to identify trophic level in archaeological human populations and to investigate paleodiet. We demonstrate that strontium isotope compositions (reported as δ88/86Sr) vary in a mass-dependent manner with increasing trophic level and can elucidate paleodiet in archaeological human populations. We present new mass-dependent strontium isotope data from tooth enamel and bone from individuals buried during the Late Intermediate Period (c. AD 1000–1300) in the large cemeteries of Chiribaya Alta, Chiribaya Baja, San Gerónimo, and El Yaral in the Ilo and Moquegua Valleys of southern Peru. We compare these data to radiogenic strontium isotope data (87Sr/86Sr) and light stable isotope data (δ15Ncol and δ13Ccol) from the same individuals to investigate geologic variability in strontium sources as well as marine food consumption among the Chiribaya. Our results demonstrate the utility of measurements of strontium isotope fractionation as a new tool for archaeological investigation of paleodiet. Importantly, this new technique can be used to generate paleodietary (δ88/86Sr) and paleomobility (87Sr/86Sr) data from the same specimen, minimizing destructive analyses of invaluable archaeological material, and provides a new way to examine paleodiet through hydroxyapatite, which is particularly important when collagen is poorly preserved.  相似文献   
6.
This paper presents evidence for severe lead contamination among children of samurai families living in a castle town in Edo period Japan (1603–1867). Excavated rib bones were analyzed by atomic absorption, and soft X-ray roentgenograms of long bones were taken. The median values of lead concentration in the bones of children 3 years of age and under(1241.0 μg Pb/g dry bone) and 4–6 years of age (462.5 μg Pb/g dry bone) were significantly higher than those of adult males (14.3 μg Pb/g dry bone) and females (23.6 μg Pb/g dry bone) (p < 0.001). In addition, that of children over 6 years of age (313.0 μg Pb/g dry bone) was significantly higher than those of adult males (p < 0.01) and adult females (p < 0.05). The median value of lead in the bones of children 3 years of age and under was over fifty times higher than that of their mothers (adult females). Hypertrophy was seen in the long bones of five samurai children. In this area, lead lines or lead bands were distinguished by soft X-ray roentgenogram. Samurai children suffered from severe lead contamination in Edo period Japan. When the mothers were nursing their children, the children might have ingested their mother’s white lead non-selectively.  相似文献   
7.
为进一步了解夏家店下层文化铜器的物料信息,探讨其矿料来源,采用多接收电感耦合等离子体质谱仪(MC-ICP-MS)对4处夏家店下层文化遗址和1处高台山文化遗址出土的部分铜器进行了铅同位素比值测定,并将测定结果同辽西地区几处金属矿的铅同位素数据进行了对比。结果表明:这4处夏家店下层文化遗址出土铜器的原料可能是使用辽西当地的大井多金属矿的矿石冶炼而成,而大山前遗址出土铜器的铅料有可能来自辽宁桓仁的多金属矿,二道井子遗址所出红铜器的铜料则可能另有来源。所属高台山文化的湾柳遗址铜器的铅同位素数据具有高放射性成因铅特征,表明其与同期其他考古学文化存在某种联系。  相似文献   
8.
Lead isotope compositions provide a direct means of assessing provenance. The lead contents in bronzes cannot be used to argue against lead isotopes. Any claim for the origin of the source material for the origin of Yin‐Shang bronzes must satisfy the measured lead isotope compositions. Thus far, only southern African sources are found to meet this criteria.  相似文献   
9.
The lead isotope compositions of many different samples from lead ingots of Roman age from two relicts (from Cabrera, and from Saintes‐Maries‐de‐la‐Mer) of the Western Mediterranean have been measured. Other lead isotope analyses of ores, metals or lead ingots from mines of Sierra Morena and from Cartagena and Sardinia have been accomplished. All the lead isotope measurements have been performed at the Joint Research Centre of the European Union, Ispra (Va), Italy. The samples have been prepared in a class 100 clean room, using only ultrapure reagents and FEP materials. In view of the archaeological arguments, it was possible to believe that the Roman lead ingots of the Saintes‐Maries‐de‐la‐Mer 1 wreck came from Spanish lodes, as well as those of the Cabrera 5 wreck. In fact, while the comparison between the first group of ingots (Cabrera 5) and the lead from Sierra Morena is consistent, the correspondence between the second group of ingots (Saintes‐Maries‐de‐la‐Mer 1) and the Cevennes ores (southern France) gives rise to several problems concerning the archaeological and physical origins. These problems are discussed.  相似文献   
10.
The Naples Yellow pigment was apparently used for the first time by the Egyptians, as a glass‐colouring agent. Also known in the Mesopotamian and Roman cultures, the recipe was lost in Western Europe between the fourth and the 16th centuries ad . The recipe for the production of lead antimonate recently discovered in the ‘Codice Calabranci’ (second half of the 15th century) at Montelupo, a small town near Florence (Italy) known for its large‐scale ceramic production, possibly represents the very first evidence of the reintroduction of Naples Yellow in Western Europe after a long period of absence. The major‐element composition of the lead antimonate pigment in the Montelupo ceramics of the 15th and 16th centuries is in accordance with the ‘Codice Calabranci’ recipes. Lead isotope analyses indicate that the lead used to produce the yellow pigments and the underlying glaze of the Montelupo majolica did not come from the Tuscan mining districts, but was possibly imported via Venice from more distant lead sources in Turkey.  相似文献   
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