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61.
A large ceramic vessel was discovered at São Brás (southern Portugal) containing a metallic hoard from the Chalcolithic/Early Bronze Age period. These weapons and tools were characterized by microanalytical techniques as being composed of copper with varying arsenic contents (2.2 ± 1.6 wt%) and minor amounts of lead, bismuth and iron. The collection shows a clear association between daggers and copper with a higher arsenic content, which can be explained by the high status of these silvery alloys. Finally, the compositional distribution of the hoard was compared with the metallurgy of the Bell Beaker and non–Bell Beaker communities inhabiting the south‐western Iberian Peninsula. 相似文献
62.
Climrio Paulo da Silva Neto Alexei Kojevnikov 《Berichte zur Wissenschaftsgeschichte》2019,42(4):375-399
At the height of the Cold War, in the 1950s, the process of parallel invention of masers and lasers took place on the opposing sides of the Iron Curtain. While the American part of the story has been investigated by historians in much penetrating detail, comparable Soviet developments were described more superficially. This study aims at, to some extent, repairing this discrepancy by analyzing the Soviet path towards the maser from a comparative angle. It identifies, on the one hand, significant differences between the two projects regarding their heuristics, the relationship between theory and experiment, grounding in different academic cultures, and the resulting conceptualization of the maser principle. At the same time, the case also illustrates more fundamental transformations in the practices of postwar research that can be characterized as a convergence between the Soviet and the American science of the period. 相似文献
63.
The Glaze Technology of Hispano‐Moresque Ceramic Tiles: A Comparison Between Portuguese and Spanish Collections
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S. Coentro L. C. Alves C. Relvas T. Ferreira J. Mirão J. Molera T. Pradell R. A. A. Trindade R. C. Da Silva V. S. F. Muralha 《Archaeometry》2017,59(4):667-684
For the first time, Hispano‐Moresque glazed tiles from Portuguese and Spanish collections were studied together and compared. This work is included in a wider study tackling the technology of Hispano‐Moresque tile production from several collections in the Iberian Peninsula. While showing many similarities, differences were identified between collections, regarding both chemical and morphological characteristics. The collection from the Mosteiro de Santa Clara‐a‐Velha (Coimbra) stands out from the other collections, with higher SnO2 content (up to 14 wt%), the highest Fe2O3 contents in amber glazes and a Ca‐rich interface layer (mostly comprised of wollastonite, CaSiO3). Samples from Palácio Nacional de Sintra (near Lisbon) and Seville‐attributed samples (from the Instituto Valencia de Don Juan) are chemically similar, except that most Sintra's samples display a K‐rich glaze/ceramic interface, whereas the ones from Seville exhibit both K‐rich and Ca‐rich inclusions. The samples attributed to Toledo show glazes with many inclusions, contrasting with the homogeneous glazes in most Hispano‐Moresque tiles. From these results, we identify differences that can be used as markers in future studies on Hispano‐Moresque tiles. 相似文献
64.
J. Alexandre Bogas Miguel Silva M. Glória Gomes 《International Journal of Architectural Heritage》2019,13(4):569-584
This article aims to characterize the physical, mechanical, and water-resistant behavior of unstabilized and stabilized compressed earth blocks (CEB) produced with partial incorporation of recycled fine aggregates from construction debris. The objective was to produce an alternative-earth construction material with lower embodied energy. To this end, different types of common CEB were covered, namely: unstabilized CEB; stabilized CEB with 8% cement; stabilized CEB with 4% cement and 4% lime. CEB were characterized in terms of density, thermal conductivity, compressive and tensile strength, water absorption, permeability, and resistance to water erosion from drip and spray tests. The influence of moisture content was also analyzed. Lime stabilization had little effect on the early age mechanical and durability behavior of CEB. Design coefficients are suggested for common cement-stabilized CEB under different environmental conditions. A minimum of 4% cement content was sufficient to produce water-resistant CEB with partial incorporation of recycled aggregates. 相似文献
65.
A. M. Silva 《International Journal of Osteoarchaeology》2005,15(6):449-453
This paper reports articular surface defects detected in three foot bones. These were exhumed from Portuguese collective burial places, Hipogeu de São Paulo II (artificial cave, Almada) and Necrópole da Serra da Roupa (shelter, Columbeira) dated to the Late Neolithic and Chalcolithic periods. Other aetiologies were presented, but non‐osseous calcaneonavicular coalition proved to be the most probable explanation for the unusual morphology detected in two calcanei and one navicular bone. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
66.
Stable Isotope Analysis of Diet‐based Social Differentiation at Late Prehistoric Collective Burials in South‐Western Portugal
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In the Neolithic and Copper Age collective burials of the Portuguese Estremadura, the majority of material culture and skeletal remains are highly commingled, making it difficult for archaeologists to evaluate social status by linking individuals with specific grave goods. In these circumstances, bio‐anthropological data about individual life histories offer an additional avenue of investigation into social complexity among prehistoric communities practising collective burial. In this study, stable isotope data were gathered from 81 individuals from seven collective burial sites and one settlement, the fortified site of Zambujal, in order to determine if significant dietary differences exist within or between burials that may point to patterns of social differentiation, both at individual sites and across the region. While in general all of the sampled individuals consumed fairly homogeneous diets based on terrestrial animal proteins and C3 plants, this study found that statistically significant differences in δ13Cap and δ15N values exist between several sites, which may indicate socially differentiated consumption of meat and plants. Additionally, statistically significant differences were found in δ15N values between adults and juveniles, which may either be attributable to protein‐restrictive child‐feeding practices or physiological processes related to skeletal growth and development. 相似文献
67.
Social Protection,Economic Growth and Social Change: Goals,Issues and Trajectories in China,India, Brazil and South Africa,edited by JamesMidgley and DavidPiachaud. 2013. Cheltenham,U.K. and Northampton,Massachusetts: Edward Elgar. 283 + xiii. ISBN 978‐1‐78195‐394‐5, $117.
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Patricio Aroca 《Journal of regional science》2016,56(2):365-366
68.
Hugo Augusto José Miguel Castro Carlos Rebelo Luís Simões da Silva 《Journal of Earthquake Engineering》2019,23(5):810-836
This paper seeks to contribute to the development and improvement of displacement-based design procedures, proposing improved ductility-equivalent viscous damping relationships for steel moment-resisting framed structures with dissipative beam-to-column partial-strength joints. These relationships can be used directly in procedures like the Direct Displacement-Based Seismic Design (DDBD) that uses effective stiffness, ductility-equivalent viscous damping relationships, and period-displacement relationships in a performance-based design approach. To this end, a finite element model of a steel beam-to-column sub-assemblage, characterized by an extended end-plate, is developed in ABAQUS. The model, which is validated against monotonic and cyclic experimental data obtained in previous research, is employed to carry out non-linear time-history (NLTH) analyses, using real records scaled to target several levels of ductility demand. A procedure is then proposed and applied to determine the ductility-equivalent viscous damping relationships of the sub-assemblages. The equivalent linearization technique is applied to the non-linear responses obtained in the NLTH analyses, using an elastic single degree of freedom structure and the elastic displacement spectra. The influence of joints mechanisms and of the dynamic characteristics of the structure in the equivalent viscous damping is investigated, and an expression for ductility-equivalent viscous damping is proposed. The proposed expression represents a clear improvement in relation to the existing expressions available in literature. 相似文献
69.
Kapila D. Silva 《International Journal of Heritage Studies》2013,19(8):820-841
There is no clear approach to defining the authenticity of the ‘spirit and feeling’ of a place or how it could inform heritage conservation. I argue that the notion of spirit of place may be defined in a manner that directly links it with the concept of cultural significance of historic places, how it is understood by a community and with heritage conservation goals and development needs of that place. Residents in the World Heritage Town of Bhaktapur, Nepal, were interviewed to explore their shared understanding of its spirit of place. The residents identify the spirit of place of Bhaktapur in terms of four interrelated place dimensions; that is, the ‘sense of sacrality’, the ‘sense of community’, the ‘sense of historicity’ and the ‘sense of serenity’. 相似文献
70.