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31.
In this work we carried out INAA major (Na, K, Ca and Fe %) and trace (ppm) elements (plus Mn by FAAS analysis) of 15 obsidian samples (waste flakes) coming from an unknown archaeological site (14C-AMS age of 1425 AD) located on the south-eastern flank of the back-arc Sumaco volcano (to the east of the Cordillera Real) and from two already known pre-Columbian archaeological localities: La Florida (Quito) and Milan (Cayambe). Literature compositional data of the Ecuadorian obsidian outcrops provide some constraints on the provenance of the analyzed waste flakes, even though different methods of analyses make comparisons a difficult task. Concerning the obsidian artifacts of La Florida and Milan, they come from the well known Sierra de Guamanì obsidian sources (Cordillera Real). By contrast, the obsidian fragments of the Sumaco settlement show some compositional characters compatible with obsidian erratic pebbles recently discovered in some river banks of the Amazonian foothills draining the easternmost flanks of the Antisana volcano in the Cordillera Real as well. In this way, the obsidian artifacts found at the Sumaco site reinforce the opinion that Ecuadorian source inventory is not yet exhaustive. Although the Antisana volcano seems to be the best candidate to find out additional primary outcrops of obsidian sources, it cannot be also excluded that sub-Andean and Amazonian people directly took advantage from obsidian secondary sources (e.g. river banks), rather than procurements from primary outcrops in the Cordillera Real. The new archaeological findings at the Sumaco volcano are really of paramount importance in tracing the ancient routes of a possible obsidian eastward trade toward the Amazonian region.  相似文献   
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In 2012, fragments of hull planking bearing the signs of a Roman‐era sewn vessel, with holes drilled along the plank edges, washed ashore on Venice Lido, the barrier island separating the Venice Lagoon from the Adriatic Sea. This paper describes the construction features of this timber assemblage and places it within the context of other excavated sewn boats of the Upper Adriatic. The assemblage presented here best fits into the north‐western Adriatic sewn tradition and likely represents either a fluvial‐maritime or maritime watercraft.  相似文献   
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Maistre studies     
This article examines the excitement that Adam Smith's Theory of Moral Sentiments generated in France during the French Revolution, focusing particularly on the writings of political theorists, participants and commentators such as the abbé Sieyès, Pierre-Louis R?derer, the Marquis de Condorcet and Sophie de Grouchy Condorcet, who were dismayed at their political opponents’ use of Rousseau, and looked to Smith for an understanding of the passions that was compatible with democratic sovereignty and representative government. In the political context of the early 1790s, clarifying the concept of natural sociability, which Rousseau had rejected, but Smith and Helvétius, in different ways, each regarded as indispensible to a society dependent on advanced division of labour, became a central concern in the public lectures delivered by Pierre-Louis R?derer as the Terror took hold.  相似文献   
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The remains of a Roman barge were found in 1981 in the River Stella, Udine, Italy. Its cargo consisted mainly of roof tiles. It was excavated in 1998 and 1999, and detailed recording of the hull, and a second wooden structure, was achieved in 2011. A spread of material upstream of the wreck has been investigated 2012–2015. The barge was originally dated to the first quarter of the 1st century AD by the in situ cargo. This article describes the bottom‐based sewn‐plank hull construction and examines it in the light of local boatbuilding traditions. The second wooden structure is also described, along with recent finds and new dating evidence from the dispersed material. The Stella 1 excavation was part of the Anaxum Project, a wider study of the Stella River's cultural landscape through time.  相似文献   
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ABSTRACT

This article attempts to describe a particular form of baraccata house, found in L’Aquila, Italy. The differences between this form of baraccato and the Italian traditional timber-framed (T-F) structures, the baraccato borbonico and the baraccato alla beneventana, are shown. In the upper valley of the Aterno river (Abruzzo, Italy), a few kilometers far from L’Aquila, wonderful 18th-century examples of T-F masonry structures are present. The use of wood pervades both the poor and noble buildings. In this article, the documentary and functional features of this peculiar anti-seismic timber-based building technique, which is widespread in L’Aquila and the neighboring areas, is described. After a comparative analysis of the technique’s features, the case of three T-F buildings, belonging to three different social classes is reported, the first is the Ricci palace in Mopolino di Montereale, the second is a middle-class building, and the third is a rural one. The 1703 earthquake, which affected the upper valley of the Aterno river and the nearby city of L’Aquila, gave rise to an ante litteram anti-seismic culture. Timber was not seen as an obstacle to durability but a material to be exploited to protect buildings from earthquakes.  相似文献   
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The Grande Aula, or Great Hall, of the Markets of Trajan (AD 96 to 115) is an intact example of the domed, concrete architecture of imperial Rome. Petrographic, x-ray diffraction, chemical, and SEM analyses demonstrate that wall mortars contain Pozzolane Rosse volcanic ash aggregate (harenae fossiciae) and strätlingite, a complex calcium aluminate cement hydrate (C2 ASH8) that gives modern cements good durability and compressive strength. Specific gravity tests and a new petrographic method for assessing bulk densities indicate unit weights of about 1750 kg/m3 for the wall mortars and 1430–1640 kg/m3 for the pumice bearing, vaulted ceiling mortars. Innovative point load source tests record the tensile strengths (ft) of the aggregate and interfacial elements of the conglomeratic concrete fabric. These suggest ft of about 2.7 MPa for brick, 1.2 MPa for Tufo Lionato tuff, and 0.9 MPa for Tufo Giallo della Via Tiberina tuff coarse aggregate (caementa), based on a tentative, approximate correlation with splitting (Brazilian) tests. The pozzolanic mortar and interfacial zones have lower ft in the range of 0.8 MPa to 0.5 MPa. The relatively low mortar strength and its somewhat tenuous adhesion to the coarse aggregate suggests that the caementa may have arrested the propagation of tensile microcracks that formed in the mortar, thereby increasing the composite tensile strength of the concrete. Roman builders selected the complex aggregate mixes to optimize the performance of the wall and vault concretes.  相似文献   
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