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In the Iberian Peninsula, the copper metallurgy from the Chalcolithic to the Middle Bronze Age (MBA) was mostly characterized by low arsenic contents. A collection of 53 MBA artefacts from southern Portugal was analysed by micro‐EDXRF, optical microscopy, SEM–EDS and Vickers to investigate the metal composition and manufacture. No technological distinction was found between artefacts from domestic and funerary contexts, which were radiocarbon‐dated to 2000–1500 cal bc . The arsenic contents of almost 100 MBA artefacts from this region, including the above‐mentioned set, have a Gaussian distribution with a high average (3.9 wt% As). Possible explanations are discussed for this distinctive metallurgy at the south‐western end of the Iberian Peninsula.  相似文献   
2.
We have determined the composition of rock art pigments from two megalithic barrows located in the north of Portugal. The use of XRD, SEM–EDS and FT–IR spectroscopy confirmed the presence of hematite and kaolinite in the red pigments from the Eireira barrow, and kaolinite in the white pigment from the Leira das Mamas barrow. The organic composition of the pigments was studied by GC–MS, suggesting that the red sinuous lines and dots from the Eireira barrow were prepared with cooked or heated algae and/or aquatic plants, with egg as binder, while the white pigment from the Leira das Mamas barrow revealed a mixture of vegetable oils for kaolinite moulding, which could be stabilized by temporary exposure to high temperatures. The multi‐analytical approach used on this study of megalithic pigments allowed the recovery of important data about north‐western prehistoric communities, namely the way in which they exploited existing resources and their ability to transform them.  相似文献   
3.
Urban developments can transform adjacent rural areas by degrading their natural resource base and environmental values. In this paper we provide evidence on the implementation of an endogenous sustainable development plan for the rural–urban environment in the city of Las Palmas de Gran Canaria. The objective was the generation of endogenous development in the rural areas by implicating the local population in developing activities in line with natural values and the recuperation of traditional cultures. At the same time, urban societies were expected to benefit from the preservation and availability of these rural environments. The plan was implemented in a large rural valley located between adjacent urban areas. The valley represents an opportunity for urban dwellers to benefit from a large rural park in the urban environment for leisure and cultural activities. The overall accomplishment of the plan was evaluated and contrasted with the benefits to the urban population, which were also measured with a discrete choice experiment. The results highlight that the principal objectives failed because of the lack of political determination to promote the participatory channels that would lead to the preservation of natural resources in a dynamic process of social change.  相似文献   
4.
Metals from a votive deposit at Moita da Ladra (Tagus Estuary) dating to the eighth century bc were studied by micro‐EDXRF, optical microscopy and Vickers testing to investigate the adoption of Phoenician innovations by indigenous communities. Artefacts are made of bronze alloys with suitable tin contents (11.6 ± 2.3 wt%) and very low iron impurities (<0.05 wt%), and were often manufactured using the long post‐casting sequence. Comparisons with indigenous and Phoenician metallurgies from western Iberia revealed a conservative technology suggesting that the spread of Phoenician innovations was very slow. In this region, the adoption of a diversified copper‐based metallurgy and reduction furnaces only seems to occur during the Post‐Orientalizing Period, c. sixth to fourth centuries bc .  相似文献   
5.
Historically, geographers, anthropologists and colonial British administrators (1860–1947) frequently mentioned two ethno-geographical categories – khoungtha and toungtha – when referring to the tribal groups in the Chittagong Hills of Bangladesh. Some of these early works considered the livelihood patterns of these groups and the nature of their social and economic interactions. However, a discussion of the changes to their vernacular built environment has escaped any serious investigation. Using empirical findings, this article examines the changes to architectural practices of lowland and highland groups in the socially and ethnically complex region of the Chittagong Hills. Narrowing the discussion to the toungtha Mru ethnic group, this article also examines religious patterns, building techniques and spatial changes in a remotely placed, relatively inaccessible part of the hills where the built environment is still a strong cultural priority.  相似文献   
6.
The publication of Part 3 of Eurocode 8 (EC8-3), dedicated to the seismic assessment of existing buildings, took place a decade ago. However, its application in engineering practice has been limited. Moreover, no studies have been conducted regarding the application of EC8-3 to steel structures. In this paper, a critical review and practical application of EC8-3 and ASCE41-13 are carried out. Issues related to the definition of the performance requirements, compliance criteria, and the consistency of the analysis procedures proposed by both standards are identified. Conceptual differences between both documents are highlighted, and several inconsistencies in EC8-3 are discussed.  相似文献   
7.
Copper ores recovered at the third millennium bce settlement of São Pedro, Portugal, were characterized by micro-Raman spectroscopy, micro-energy dispersive X-ray spectrometry (micro-EDXRF) and micro-particle-induced X-ray emission spectrometry (micro-PIXE). The collection shows the common presence of secondary copper minerals (malachite, pseudomalachite and libethenite) combined with iron oxyhydroxides (hematite and goethite), while arsenic-rich minerals are absent and, therefore, can be excluded as the source of arsenical copper. Overall, these copper ores suggest a primitive technology involving the exploitation of the superficial zone of ore bodies and reliant on the fortuitous finding of arsenic-rich sources to produce the arsenical copper alloy frequently present among metallic collections of the Iberian Peninsula.  相似文献   
8.
The composition and manufacture of Late Bronze Age metallic artefacts from funerary and domestic contexts of southern inland Portugal was studied. The prevailing trend comprises binary bronzes (10.3 ± 2.1 wt% Sn) showing deformed equiaxial grains, annealing twins and slip bands. The alloy composition is somewhat independent of artefact type, while the manufacture seems to rely on artefact function and the skilfulness of the metallurgist. The technological characteristics were linked with archaeological and chronological features, disclosing some artefacts of uncommon composition, such as low‐tin bronze bracelets (4.3–7.1 wt% Sn) associated with ornaments of exotic materials (glass and Egyptian faience beads, and also ostrich egg shell beads). The assemblage testifies to an archaic trade with the Mediterranean region before the establishment of the first Phoenician colonies on the southern Iberian coast.  相似文献   
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