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971.
972.
The accumulated published database of stable lead isotope analyses of ore and slag specimens taken from Anatolian mining sites that parallel the Black Sea coast has been augmented with 22 additional analyses of such specimens carried out at the National Institute of Standards and Technology. Multivariate statistical analysis has been used to divide this composite database into five separate ore source groups. Evidence that most of these ore sources were exploited for the production of metal artefacts during the Bronze Age and Phrygian Period has been obtained by statistically comparing to them the isotope ratios of 184 analysed artefacts from nine archaeological sites situated within a few hundred kilometres of these mining sites. Also, Appendix B contains 36 new isotope analyses of ore specimens from Central Taurus mining sites that are compatible with and augment the four Central Taurus Ore Source Groups defined in Yener et al. (1991).  相似文献   
973.
This paper examines developments in bilateral planning in the border regions of Mexico and the US. Pressures of globalization and regional integration are transforming institutions and communities in these border regions, changing planning from a diplomatic to a transborder and translocal process. Drawing on institutional examples and community case studies, the paper highlights the role of political mobilization and community collaboration across the border as an effective mechanism to address Mexican-US border region planning issues.  相似文献   
974.
Among the Nigerian cast copper‐alloy artefacts, the chronology of the Benin memorial heads has been the most fully worked out. Therefore, a study focused upon their elemental compositions is particularly likely to be interpretable in terms of development of the alloys used in their making. The elemental analyses, both published and unpublished, of 66 Benin heads, supplemented with seven analyses of some artefacts excavated from a well‐dated, very early Benin site, have been collected, analysed statistically and computed to the elemental analyses of 11 heads and figures from Udo. All but a very few of the Benin heads and artefacts separate into five compositional groups, indicating a chronological sequence of different alloying traditions. All but one of the Udo objects fall into a distinctly separate compositional group, together with two Medicine heads. The compositional groups correlate remarkably well with the stylistic types proposed by Dark.  相似文献   
975.
976.
The application of solid state electrochemistry techniques for the characterization and dating of leaded bronze objects is described. Characteristic voltammetric signatures of copper and lead corrosion products were used as markers of more or less prolonged corrosion periods. The proposed methodology was applied to samples from the Roman archaeological sites of Valeria (Spain) and Gadara (Jordan), Roman and medieval sites in Xàtiva (Spain), and modern statuary exhibited outdoors, on the campus of the Universitat Politècnica of Valencia, Spain, covering a time interval between the fourth to second century bc and the 20th century ad . For such samples, the ratio between the signals for copper and lead corrosion products decreased monotonically with the corrosion time. This variation was modelled on the basis of thermochemical and kinetic considerations, the experimental data being consistent with a potential rate law for the corrosion process.  相似文献   
977.
Samples of ancient Indian lime plaster have not previously been analysed. Excavation of a seventh century AD baked brick structure provided the necessary samples for a detailed laboratory examination of plaster. The plaster samples were studied by chemical and petrographic methods. The probable sources of lime and sand were indicated by the mineralogy.  相似文献   
978.
Over 200 sherds of samian and colour-coated pottery of late 2nd or early 3rd century date have been analysed by inductively coupled plasma (ICP) emission spectrometry. Most of this material was excavated at Colchester, England; the remainder is related East Gaulish material. Some clay samples were also analysed. The material divides, after multivariate statistical analysis, into 11 clusters. These accord well with known archaeological evidence and suggest assignments of origin where these are uncertain. In particular, the archaeological evidence for a link between Colchester and the Sinzig potters is supported.  相似文献   
979.
980.
The main purpose of magical gems was to secure divine protection, avert evil influences and heal various diseases. Some body parts are especially addressed, such as the stomach and the uterus. This concern seems to relate to ‘societal diseases’ also found in contemporary literature. How do these ‘healing pictures’ function? The analysis of the pictorial elements reveals different levels of therapeutic efficacy. Some images use visual plays upon words, others combine Egyptian and Graeco‐Roman elements, allowing ‘bilingual’ readings. The mnemonic function of images, charakteres and voces magicae also requires further investigations. Objects could transmit the memory of oral rituals and knowledge. The transfer of magical figures on other media is very rare, but when it occurs, as on a few medical devices, it may help us to understand the mechanism of medico‐magical performance, combining formalism and inventiveness.  相似文献   
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