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In this work, we present the results of the characterization of 20 lime plaster samples taken from the Sacred Precinct of Tenochtitlan (Mexico City), the ancient capital of the Aztec empire. The samples come from different buildings of this precinct (A, B and D) and from the west façade of phase VI of the Templo Mayor pyramid. The objective of the work is to characterize the plaster samples, to understand the raw materials used, and to evaluate the presence of similarities and differences among the samples in the building techniques and raw materials employed. All the samples were studied with OM, SEM–EDS and LA–ICP–MS. The study provided evidence of the plastering and replastering practice in the same constructive phases. The results of the analyses showed the existence of important similarities and differences among buildings and constructive phases in the Sacred Precinct. In order to understand the provenance of the limestone used in the plasters, the lumps and the binder of the samples were analysed. The results were compared with those of the limestone outcrops located in central Mexico. The provenance study showed that all the limestone used in the construction of the analysed buildings of Tenochtitlan's Sacred Precinct comes from the Tula region.  相似文献   
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Numerous scholars have outlined what they believed to be the consequences of the advent of iron technology in sub-Saharan Africa: increased food production using more efficient bush clearing tools; increased population densities; larger and more stable communities; increased trade, specialization and social differentiation; and the embryonic rise of modern politics. (Davidson 1974.) However, little has been demonstrated in the field.A regional study of the Bassar iron industry of northern Togo has shown that the rise of large-scale iron production may lead to higher population densities, larger and more stable communities, a more aggregated settlement pattern in the ore zone, and increased craft specialization and trade. However, it does not necessarily result in a significant increase in the degree of political centralization. The Bassar data also suggest that even the appearance of relatively small scale iron production may generate similar trends, albeit at more modest levels.
Résumé De nombreux auteurs ont décrit ce qu'ils proposent d'avoir été les conséquences de l'adoption de la technologie de fer dans l'Afrique au sud du Sahara: augmentation de la production de nourriture à l'aide des outils plus efficaces pour débroussailler le paysage; augmentation des densités de population; communautés plus grandes et plus stables; croissance de la commerce, de la specialisation artisanale et de la differentiation sociale; et naissance embryonique de la politique moderne (Davidson 1974). Cependant il n 'y a que très peu de ce schéma qui a été validé par les recherches sur le terrain.Une étude régionale de l'industrie du fer des Bassar du nord de Togo a montré que l'essor de la production de fer à grande échelle peut aboutir à des densités de population plus hauts, des communautés plus grands et plus stables, une répartition de l'habitat plus agrégée dans la zone des minerais de fer, et l'augmentation de la specialisation artisanale et du commerce. Cependant il n'aboutit pas obligatoirement à une centralisation importante au niveau politique. Les résultats fournis par cette étude des Bassar nous amènt à proposer aussi que même l'apparition de la production modeste de fer peut donner naissance à des développements comparables, mais d'un ampleur plus restreint.
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During the last restoration of the Fontana di Trevi -Rome (2014–2015), it has been performed a diagnostic investigation to characterize the materials used to build and obtain the colors of the surfaces of some architectural elements of this fountain. According to the restoration teamwork needs, we focussed our efforts on the dome over the central statue of Oceanus, on the bas-relieves on the sides of the dome, and on the cliff where the water flows. Several samples were collected from these elements and therefore, they were subjected to an analytical approach including infrared spectroscopy, optical and scanning electron microscopy. The achieved results indicated the use of red earth pigments on the dome. The same pigment has been revealed on the bas-relieves, although their colors have an additional contribution due to degraded layers. Samples taken from the cliff showed a complex stratigraphy, although a white scialbo has been identified as original layer, testifying the intentions of the authors in term of color rendering. This information was essential for the restores in order to choose the proper intervention procedure for each investigated surface. The research testified the importance of an integrated diagnostic analysis to preserve the original colours of monuments and building.  相似文献   
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作为当今国际学术界一位知名且相当有成就的荷兰东印度公司的档案学专家 ,包乐史教授充分搜集和系统运用荷兰文与中文的历史档案文献来研究华侨华人历史 ,尤其是 1 7、 1 8世纪东南亚华侨史、东南亚华商贸易和当时华侨的社会问题 ,从而构成了包教授对华侨华人历史研究的最主要的特色和成就。  相似文献   
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79 samples of black glazed pottery, Terra sigillata, fine common ware, and production indicators were recovered in the archaeological site of Cales and investigated via a multi-analytical program (polarized light microscopy, thermal analyses, XRPD, XRF, FESEM, FESEM-EDS). Among the materials, finds of important production indicators, represented by welded pieces of black glazed pottery and spacers, attest a local production. Polarized light microscopy shows that the inclusions consist of feldspar, quartz, mica, calcite, and lithic fragments of both volcanic and sedimentary nature. Additional information about the mineralogical assemblage comes from the XRPD that revealed the presence of neoformed Ca-silicates, indicating equivalent firing temperatures ranging from 750 to 1050°C. All the samples show a Ca-rich character and an extreme compositional homogeneity, including the production indicators. The comparison with some Ca-rich Campanian clay raw materials shows a greater affinity with the Mio-Pliocene marine clay sediments of the Apennine sector, which include local clays. This allowed us to formulate the first hypotheses about clay sources used to produce fine pottery during the third century BCE to the early imperial period in Cales.  相似文献   
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Situated along the southern fringe of the North Sea basin, northwest Belgium holds great potential for understanding hunter–gatherer responses to environmental change at the Pleistocene–Holocene transition. Recent intensive fieldwork has yielded valuable data on the palaeoenvironment, chronology, and hunter–gatherer mobility and land use in this region. At the Late Glacial/Early Holocene transition this region was comprised of a landscape of coversand ridges and lakes that flanked the northern part of the Scheldt river basin. This landscape was highly productive for hunter–gatherer populations. As the landscape developed in response to the increasing water table caused by the inundation of the North Sea populations responded by changing their forms of mobility and land use. These changes are indicated by the reduction in the number and density of sites, as well as their geographical settings, from the Late Glacial (Federmesser) and Early Mesolithic to the Middle-Final Mesolithic. Late Glacial/Early Mesolithic sites indicate much higher mobility comprised of rapid displacements of camps and re-occupation of the same coversand ridges over long time-spans. Middle/Late Mesolithic sites indicate a reduction in mobility, increasing focus on prolonged riverside settlement, and a more rigid organization of residential sites.  相似文献   
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The purpose of this paper is to demonstrate cross‐Channel exchange of calcareous sandstone‐type whetstones derived from the Weald (Sussex, UK) in the Roman period. The presence of this particular type of whetstone at several Roman sites on the Continent – more specifically, in Belgium, France and the Netherlands – is reported for the first time. The morphology, geological provenance, petrographic characteristics and distribution patterns are discussed, based on a comparative analysis with archaeological and geological reference material. The geological analysis identifies a common geological source for the Continental finds: the very fine‐grained, thin‐bedded, flagstone‐like calcareous sandstone beds of the Lower Cretaceous Wealden Clay Formation. These sandstones were, most probably, extracted in the north‐western part of the Weald area. The distribution pattern of the archaeological material implies the importance of personal mobility, with potential military affinities.  相似文献   
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