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F. Albarde J. Blichert‐Toft F. de Callataÿ G. Davis P. Debernardi L. Gentelli H. Gitler F. Kemmers S. Klein C. Malod‐Dognin J. Milot P. Tlouk M. Vaxevanopoulos K. Westner 《Archaeometry》2021,63(1):142-155
The reasons why the Western Mediterranean, especially Carthage and Rome, resisted monetization relative to the Eastern Mediterranean are still unclear. We address this question by combining lead (Pb) and silver (Ag) isotope abundances in silver coinage from the Aegean, Magna Graecia, Carthage and Roman Republic. The clear relationships observed between 109Ag/107Ag and 208Pb/206Pb reflect the mixing of silver ores or silver objects with Pb metal used for cupellation. The combined analysis of Ag and Pb isotopes reveals important information about the technology of smelting. The Greek world extracted Ag and Pb from associated ores, whereas, on the Iberian Peninsula, Carthaginians and Republican‐era Romans applied Phoenician cupellation techniques and added exotic Pb to Pb‐poor Ag ores. Massive Ag recupellation is observed in Rome during the Second Punic War. After defeating the Carthaginians and the Macedonians in the late second century bce , the Romans brought together the efficient, millennium‐old techniques of silver extraction of the Phoenicians, who considered this metal a simple commodity, with the monetization of the economy introduced by the Greeks. 相似文献
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In 2022, an Athenian red-figured cup attributed to Makron was returned to Italy by New York’s Metropolitan Museum of Art. The cup had been acquired in fragments, through purchase and gift, from multiple sources over several years, starting with two fragments from the restorer Fritz Bürki in 1978. A second cup, also attributed to Makron, was acquired in a parallel way. The sources for the fragments from both cups point to galleries collectors and donors – Summa Galleries, Frieda Tchachos, Elizabeth Hecht, and Dietrich von Bothmer – who have been associated with other material that has been repatriated to Italy in recent years. It is suggested that some of the incised ‘signatures’ by Hieron that are found on cups attributed to Makron may have been applied since antiquity. 相似文献
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As technologies grow in complexity, firms often target their internal R&D resources on core competencies and utilize outside sources for supporting knowledge and technology. Where do firms turn to find such resources? This paper reports the perceptions of technology transfer managers in United States manufacturing firms toward federal and university labs and identifies the types of farms that are better positioned to utilize externally available technological resources. Based on replies from research-intensive companies within the United States, the authors find that larger firms with high research and development (R&D) budgets tend to ascribe greater significance to external sources than do smaller ones. Also, companies spending over $500 million in R&D rank universities the most significant external source of knowledge, followed by V S.-based firms, and then foreign firms. 相似文献
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Current federal hazardous and low-level radioactive waste management policies (under conjoint federalism) fail to balance national concerns for consistency with state concerns for equity, discretion, and adequate resources. Congress should expand conjoint federalism to permit states to charge differential fees on imported hazardous waste as it does for low-level radioactive waste. For low-level radioactive waste, clarification of the "take title" issue makes the present framework for state discretion implementable, given sufficient time. 相似文献