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31.
Mineralogical, petrographic and chemical analyses were performed on thirty-eight samples of transport amphorae found at Gela, an important Greek colony on the southern coast of Sicily. Based on macroscopic observation, the amphorae, which are datable between the second half of the 6th and the end of the 5th century B.C., were supposed to be local because of similarities to the common wares from the same site. Therefore, in order to verify the provenance of the samples, they were compared to a reference group of locally made ceramics (kiln spacers, kiln wasters, common wares, ancient mud bricks, modern bricks) and twelve samples of local clayey sediments. The results of the analyses have allowed the assignment of all the amphorae to Gela, with the exclusion of five samples, maybe produced in neighbouring sites, and to determine for the first time the archaeometric characteristics of the Geloan medium-coarse ceramics. The aim of our research has also been to investigate some technological aspects of this production, as the location of the clay sources, the methods of clay preparation, and, in particular, the causes of the typical whitening effect on the surface of the vessels.  相似文献   
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The present paper reports the results of archaeometric characterisation of the opaque tesserae, intentionally coloured with antimony- or phosphorus-based opacifiers, coming from one of the two only palaeo-Christian glass mosaics known in the Veneto region (Italy), i.e., the mosaic which decorated the votive chapel of St. Prosdocimus in Padova. In particular, 55 tesserae belonging to glass types “White”, “Blue”, “Yellow”, “Green” and “Brown” are examined here. The multi-methodological approach (SEM-EDS, EMPA, XRPD, imaging spectroscopy coupled, in some cases, with XAS) gave valuable insights into the complexities of palaeo-Christian glass mosaic production technologies. Two main groups are identified, one characterised by glassy matrixes and opacifiers (calcium or lead antimonate) typical of the Roman period and comprising all “White”, “Blue”, and “Yellow” tesserae and some “Green” ones, and the other characterised by glassy matrixes and an opacifier (calcium phosphate) typical of the 6th century AD, composed of “Green” and “Brown” tesserae. This suggests that, during that century there was a gradual change from older to “new” production technologies: although new opacifiers such as calcium phosphate started to be used, the frequent use of antimony-based ones (43/55 samples) supports the hypothesis that their systematic use was extended until the 6th century, although re-using old tesserae cannot be completely excluded. In addition, comparisons with compositional groups already identified in the “gold” tesserae of the same mosaic and tesserae from Ravenna demonstrate that both the same “base compositions” of the glass were used to produce transparent and opaque glass. This evidence, coupled with the results of the historical-artistic study, suggests technological connections between Padova and Ravenna, the capital of Byzantine mosaics in Italy. Micro-structural observations and chemical analyses of the Paduan antimony-based opacified glass demonstrate that different processes and raw materials were used in their production. Both in situ and ex situ crystallisation can be identified for calcium and lead antimonate in Paduan tesserae, whereas the production of tesserae opacified with calcium phosphate generally appears to be highly standardised. Although the opacifiers used in the Paduan tesserae support technological transitions, the colouring elements identified here, i.e., iron and manganese for white, yellow, brown and some green tesserae, cobalt for blue, and copper for blue and green, suggest continuity, because their use is widely testified in the production of both transparent and opaque glass artefacts dating from the Bronze Age until Medieval times, from whichever archaeological site the samples come. Peculiar relationships among the oxidation states of colouring elements, their contents in the glassy matrix, the types of opacifiers used, and the final colour of tesserae were identified. In addition, the correlations of cobalt and/or copper with other elements, together with identification of relics of colouring and “metallic” droplets, allow us to speculate on possible sources and production technologies. Lastly, identification of newly formed crystalline inclusions in tesserae also yields information on kiln temperatures, which ranged between 900 and 1150 °C, a range easily reached in the furnaces of the 6th century AD.  相似文献   
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We introduce a direct Displacement-Based Design methodology for glued laminated timber portal frames with moment-resisting doweled joints. We propose practical expressions to estimate ultimate target displacement and equivalent viscous damping, and we demonstrate that these expressions provide prior values that are close to those obtained a posteriori using a more refined model. Applied to case studies, the method yields base-shear forces lower than those obtained using the force-based approach of Eurocode 8. This is due to the high dissipation capacity of the specific connection technology, which apparently is conservatively accounted for in the q-factor of Eurocode 8.  相似文献   
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Hospitals are critical infrastructures which are vulnerable to natural disasters, such as earthquakes, man-made disasters and mass causalities events. During the emergency, the hospital might also incur in structural and non-structural damage, have limited communication and resources, so they might not be able to treat the large number of incoming patients. For this reason, the majority of medium- and large-size hospitals have an emergency plan that expands their services quickly beyond normal operating conditions to meet an increased demand for medical care, but it is impossible for them to test it before an emergency occurs. The objective of this article is to develop a simplified model that could describe the ability of the Hospital Emergency Department to provide service to all patients after a natural disaster or any other emergency. The waiting time is the main response parameter used to measure hospital resilience to disasters. The analytical model has been built using the following steps. First, a discrete event simulation model of the Emergency Department in a hospital located in Italy is developed taking into account the hospital resources, the emergency rooms, the circulation patterns and the patient codes. The results of the Monte Carlo simulations show that the waiting time for yellow codes, when the emergency plan is applied, are reduced by 96%, while for green codes by 75%. Then, using the results obtained from the simulations, a general metamodel has been developed, which provides the waiting times of patients as function of the seismic input and the number of the available emergency rooms. The proposed metamodel is general and it can be applied to any type of hospital.  相似文献   
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Abstract

Is there a connection between war and madness? How have psychiatrists responded to the problem of those ‘driven mad by war’? This article tries to answer these questions by drawing on clinical records for three Italian psychiatric hospitals in the period from 1940 to 1950. While these problems have been researched and debated for combatants during the World War I, in the case of the World War II, as this article shows, it is necessary to take into account the impact of war not only on soldiers but also on civilians who were equally involved in the trauma of war.  相似文献   
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We present the find of impact scars on six Middle Paleolithic points from the rock shelter site of Oscurusciuto in southern Italy, dated to MIS 3. We review our knowledge of hunting weapons in the European Middle Paleolithic, the available evidence for the use of Mousterian points as spear tips and the interpretations of impact scars. Our identifications are based on comparisons to similar scars observed on experimental material and archaeological material of known function, made of the same raw materials (cryptocrystalline varieties of silica) as the points from the Oscurusciuto site. The scarce evidence available prior to our work suggested that at least some Mousterian points were used to tip hand-delivered spears already by MIS 6 (i.e. between 186 and 127 ka). The evidence from Oscurusciuto confirm that Neanderthals in Western Europe sometimes used Mousterian points to tip spears to hunt large and medium size mammals, like the fauna present at the Oscurusciuto site. The significance of this sample is not diminished by its small size, as indicated by a discussion of the factors that influence the frequencies of impact scars in different archaeological samples and a review of comparable evidence from residential sites of similar and younger ages.  相似文献   
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