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21.
Blue‐on‐blue (‘berettino’) sherds have appeared in numerous production and consumption archaeological excavations in Lisbon and other archaeological sites in Portugal (dated from the mid‐16th century to the beginning of the 17th century). The abundance of this interesting faience led us to compare it with similar pottery from other well‐known production centres in Italy, namely Liguria (Savona and Albisola), Spain (the Triana kilns) and the Low Countries. Differences in the diffraction patterns of the sherds' pastes from the four countries were observed. In most samples, cobalt blue silicate (cobalt olivine) was identified in the dark blue or light blue glazes through the use of micro‐Raman spectroscopy and diffuse reflectance spectra. A remarkable difference in the calcite contents of the Lisbon and Seville pottery sherds was observed, in accordance with previous observations of high calcite contents of Seville ceramics. A comparison was also made for all of the blue‐on‐blue sherds studied here with many other 16th–17th century sherds from Lisbon using bivariate plots of K/Si versus Ca/Si. Lisbon and Seville pottery behave very differently, whereas sherds from Italy and the Low Countries occupy intermediate positions.  相似文献   
22.
At the turn of the twentieth century, private grain exchanges settled the daily prices for North American wheat. By the end of the Second World War, the Canadian and US governments had intervened significantly in these markets. The Canadian government required farmers in its western provinces to deliver their product to the Canadian Wheat Board (CWB), a single-selling-desk agency that, by then, had supplanted private wheat marketing in western Canada. Meanwhile, the United States government subsidized farm incomes with domestic-use taxes and import tariffs, but otherwise preserved private wheat marketing. In this article, I demonstrate that these disparate agricultural policies were broadly defined by immutable economic realities imposed on each country by global wheat-trade patterns and triggered by unprecedentedly severe agricultural crises. That is, amidst the precipitous fall in wheat prices in the early 1930s, each government crafted farm-support policies that reflected its domestic-consumption share of wheat production and the importance of wheat to its overall economy.  相似文献   
23.
Lithic assemblages recovered from sites located in the eastern Pampa–Patagonia transition include a great diversity of raw materials, some from neighbouring regions, such as the Humid and Dry Pampa subregions and Northpatagonia. Lithic raw material assignments to specific procurement areas were preliminarily proposed based on macroscopic characterizations. The aim of the paper is to present the results obtained from the petrographic thin sections of archaeological artefacts from Middle and Late Holocene sites recorded at the study area. The analyses corroborate most of the macroscopic determinations, and more detailed knowledge of the acquisition areas of these raw materials was obtained.  相似文献   
24.
In this article, GPR – Ground Penetrating Radar and inductive electromagnetic (EM38 equipment) results are presented for three archaeological sites of shell mounds located between Laguna and Jaguaruna cities, mid-southern coast of Santa Catarina state, Brazil. The Jabuticabeira II, Santa Marta IV, and Encantada III sites were studied. These sites consist of carbonate shell mounds built by societies that inhabited this region during the pre-colonial period (7.5–1.3 ky BP). Geophysical responses obtained in these archaeological sites had allowed the identification of anomalous regions related to archaeological point targets as well as continuous targets, correlated to the shell mound's structure and buried geologic features. GPR numerical modelling studies were done in order to evaluate the performance of the GPR method in relation to materials found in that environment, besides helping interpretations of real results. The synthetic GPR model was a good match with real data obtained in the field. So, the real and synthetic results serve as a reference guide to direct excavation activities in these archaeological and geological structures. In the Jabuticabeira II shell mound, lithic materials and burials were found amidst archaeological layers characterized by sediment rich in organic material, ferruginous concretions, and loose shells. In the Santa Marta IV archaeological site, a concentration of ceramic materials, burials and fireplaces were found. In the Encantada III site, a strong anomaly characterized by a hyperbolic reflection was related to the presence of a silicified tree root; a great example of ambiguity in shallow geophysics interpretation in archaeological applications. Results functioned as a guide to archaeological excavations, allowing cost and time reduction as well as contributing to improve the knowledge of these archaeological sites situated in southern Brazil.  相似文献   
25.
We present results of electrical conductivity profiles obtained with inductive electromagnetic geophysical method in Santa Marta archaeological site, Santa Catarina State, southern Brazil. This site is a sambaqui (shell mound), in which several human occupation remains are found during pre-colonial period such as buried lithic and bone artifacts, fire-place, etc. Most of these mounds include as well many human burials, which, in many cases, point to funerary ritual as a main agency for mound building. A set of profiles of apparent electrical conductivity and magnetic susceptibility was acquired in two sites aiming the identification of geophysical anomalies with potential interest for excavation. To enhance conductivity data, we applied an effective procedure to remove topographical effects in the apparent conductivity measurements, which are rather conditioned by the presence of a variable water table depth or conductive sediment layer. A linear dependence among conductivity values and the site elevation provided a simple linear model to remove the influence of topography. Corrected electric conductivity maps substantially improved the definition of anomalies, many of them rather subtle in raw data images. Corrected maps also show a better adherence with magnetic susceptibility maps, both of them identifying archaeological structures of interest: a well-structured fire-place and a concentration of ceramic fragments.  相似文献   
26.
In the present study the author examines the migratory practices of movement between France and Portugal of young French of Portuguese ancestry, as well as of young Portuguese living in France. The study of these practices from an ethnological point of view sheds light on the interaction of material resources and the multifaceted symbolic resources associated with them. Besides the economic and political dimension in which these practices are grounded, the identity — forming process of which they are a part raises a number of questions — especially in the context of the European Union. The author shows how, by using elements drawn from the family migratory history, natural history and Portuguese culture, the descendents of Europeans who migrated for economic reasons are now trying to go beyond the dilemma of an identity posed by their «double culture», as well as the social and cultural constraints imposed on them by their elders.  相似文献   
27.
Fire safety is an important issue of building safety, especially when the building’s fire load contents enhance the risks of fire deflagration. When existing timber structures are involved, the most usual way to improve its reaction to fire is to treat wood with fire retardants. This study focuses on the surface protection of existing timber roof structures against fire, through the use of fire retardant (FR) treatments applied on site. An experimental investigation was carried out to study the effect of FR treatments on timber reaction to fire, with a special emphasis on timber members with biological deterioration and previously treated with preservative products. The behaviour and effectiveness of intumescent and non-intumescent treatments was also investigated. The study showed that the application of FR treatments improved the reaction to fire of timber, even in the presence of previous preservative treatments. However, the choice of the specific FR treatment should take into account the substrate conditions. In addition, test results suggest that protection systems involving multi layers (intumescent and non-intumescent) with different functioning modes each are likely to have a good global performance on the protection of timber elements against fire.  相似文献   
28.
29.
Contemporary cities have witnessed the emergence of new real-estate products in which gated communities and closed condominiums (CCs) can be included. The proliferation of these urban products is worldwide, with similar patterns that are analysed in this paper according to five perspectives of analysis: physical, economic, social, political and cultural. These perspectives cross-cut some of the main issues of discussion of the contemporary urban debate associated with private residential developments. These developments seem to appeal to an increasing number of social groups and have been able to adapt to different planning systems. With a smaller scale, these developments emerged in Portugal in the form of CCs, and are analysed in a case study in Greater Oporto. The purpose of this paper is to present the Portuguese singularities of this phenomenon in comparison with the worldwide dimension. In our case study we find some important particularities strongly associated with the Portuguese planning system. Some of these particularities have negative impacts on the surrounding urban landscape. As a result, CCs demand specific planning policies to counteract the negative consequences they are likely to generate in local social and urban fabrics. In the absence of these policies, CCs, as well as other private residential developments, are likely to contribute further to an increasingly fragmented and divided urban landscape.  相似文献   
30.
In a world in growing turbulence, complexity and uncertainty, where crisis is becoming the norm rather than the exception, resilience is increasingly seen as a critical feature that reflects the capacity of a system to absorb disturbance and reorganize without collapsing. Resilient systems are more adaptable to change, are more able to learn and are less vulnerable to disturbance and external shocks (e.g. natural phenomena, economic crises or political shifts). The resilience theories are re-emerging as a field of research and practice with application to socio-ecological systems, fostering new insights in the discussions about sustainable development. The main purpose of this paper is to explore resilience as a concept and as a framework for promoting more sustainable trajectories, highlighting its potentialities and advantages for policy and planning processes. SPARK, or the strategic planning approach for resilience keeping is introduced in the paper as a new sustainability framework, following key underlying concepts and seven key principles that capture the essence of resilience theories. The paper advances a methodological concept proposal for resilience assessment and planning that aims to contribute to linking theory and practice, performing knowledge brokerage and enhancing policy learning.  相似文献   
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