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21.
Three different lithotype groups have been recognized in representative fragments of pietra ollare artefacts found in the mediaeval archaeological excavations of Comacchio (Italy). Petrographic, mineralogical and chemical compositions clearly show that Valchiavenna and Valmalenco, in the Central Alps, represent the provenance areas of two of the pietra ollare groups, i.e. grey carbonate talc schist (also known as soapstone) and green chlorite schist, respectively. The third representative pietra ollare group consists of whitish-yellowish rocks inferred to be Alpine talc schists that have suffered some artificial pyrometamorphic transformation hindering their classification in the framework of pietra ollare lithotype categories and source localities reported in literature. A distinguishing feature of these high temperature-fired (HT-fired) talc schist samples is the occurrence of talc and chlorite dehydroxylation and subsolidus reaction products, mainly protoenstatite/enstatite + forsterite, together with relatively low loss on ignition values. These talc schists might have been exposed to temperatures >900 °C (with the resulting talc dehydroxylation producing a void-rich texture), but never reaching 1200 °C, which is the sintering temperature for soapstones. The whitish-yellowish artefacts were definitely not used as containers for cooking food at temperatures below or around 500–600 °C (as instead shown by the preservation of the original physical features of the grey pietra ollare lithotypes), but in some kind of higher-T pyrotechnological processes.  相似文献   
22.
ABSTRACT

Disaster risk mitigation has become a urgent global need. Similar to other natural hazards, earthquakes may cause significant damage on a large scale. In Europe and in other regions with dense urbanization, seismic events can heavily impact historical city centers due to the several structural fragilities. These centers are often part of the worldwide cultural heritage and their preservation is considered a strategic issue. Furthermore, earthquakes may have severe negative short-term economic effects on the impacted communities and adverse longer-term consequences for economic growth. For this reason, the development of an efficient approach for urban seismic risk assessment becomes essential. An original approach is proposed, based on performance concepts and multidisciplinary perspectives. The procedure is applied for validation to the city center of Concordia Sulla Secchia (Italy), damaged by the 2012 Pianura Padana Earthquake (PPE), comparing predicted damage scenarios with the actual post-seismic survey data.  相似文献   
23.
Iulia Concordia is an important Roman settlement known for the production of iron objects and weapons during the Roman Empire. A huge number of well-preserved styli were found in the bed of the main channel of the city. In order to shed light on the production processes used by Roman for stylus manufacturing and the conservation state of the finds, a neutron tomography analysis was performed on NEUTRA beamline in Switzerland. SEM-EDS analyses were performed on few selected objects in order to identify the composition of metal decorations. Here, we present results from our investigation conducted on 91 styli, disclosing, in a non-invasive way, the morphological characterization related to the ancient Roman working techniques.  相似文献   
24.
Chert from the limestones and marly limestones of Castelltallat Formation (Ebro Basin) was widely used throughout prehistoric times in north-eastern Iberia to produce stone tools due to its properties and accessibility. A rough estimate indicates that this rock—either as raw material or as lithic products—was distributed mainly to the north of the outcrops, over an area of 6000–8000 km2. However, other rocks in the area have similar characteristics which can lead to confusion in the interpretation of its prehistoric use and distribution. In order to establish useful archaeometric criteria for differentiating this chert from other similar, the Castelltallat chert is characterised in petrographic, mineralogical and geochemical terms. The chert nodules are found to be homogenous at the macroscopic and microscopic level, with a significant presence of bioclasts, thus indicating they might be formed in a freshwater lake environment by the early diagenetic replacement of carbonates in shallow waters. The mineralogical composition is homogeneously uniform and of a flint type, characterised by an almost exclusive predominance of quartz, without any opaline phases, and a variable proportion of moganite. The iron oxide content is very low, whereas its chemical composition is unusually high in uranium which correlates positively with carbonate content and negatively with silica. Archaeometrical parameters are provided to reach a proper identification of tools knapped with this chert. This way, chert from Castelltallat Formation turns out to be a valuable lithological marker to evaluate the range of mobility of the human groups who lived in the north-eastern Iberia and their contacts with neighbouring areas.  相似文献   
25.
Abstract

This article analyzes the development of different political tendencies with the Italian Church during the pontificate of John Paul II. Two different strategies enabled the episcopal conference to maintain stability for a long period, in which time Cardinal Ruini played a key role, first as secretary and then president of the bishops. In his years the conference of bishops accepted that the political unity of the Catholic world was over, but it still tried to retain a strong political influence even though the mediation of the Christian Democratic Party was no longer available. With the end of Wojty?a's pontificate, however, this period came to a close and the different tendencies that make up the rich and complex world of the Italian Catholic Church have become more visible.  相似文献   
26.
A new method called the Baseline Stiffness Method (BSM), used to locate and quantify damage in buildings without baseline modal parameters (undamaged state), is presented. In order to determine this reference state, the BSM uses modal parameters from the damaged state of the building and the lateral stiffness matrix of the first story without damage. Afterwards, by means of an iterative process using singular value decomposition, location and severity of damage are obtained by comparing information about the damaged and non damaged states. Numerical and experimental examples are presented and discussed showing the advantages of the application of the proposed BSM.  相似文献   
27.
A brief overview is provided on the development of histology as an independent discipline at the University of Pavia, through documents and preparations preserved in the Museum for the History of the University. Studies on the organization of tissues and cells started blooming in the mid-1850s, when morphological observations were supported by significant technical advancements in microscopy and tissue preparation. The role of Albert Koelliker, the great father of European Histology in the second half of 19 th century, is also discussed. Koelliker had several contacts with Camillo Golgi and promoted the diffusion of Golgi's discoveries. The authors also underline the innovative role of Camillo Golgi in the histological approach to research and in the foundation of modern histology.  相似文献   
28.
The metropolitan urbanization shows evidence that planning at the regional, subregional and municipal levels with its wide range of territorial, urban and sectorial competences is now longer able to significantly influence territorial development. This has led to a greater demand for alternative approaches, methods and instruments. For this research study, the metropolitan area of Granada was used as a field laboratory to assess the capacity of metropolitan planning to have an impact on metropolitan processes and dynamics. For this purpose, a method for metropolitan planning evaluation, MPE methodology, was proposed, which involves two evaluation processes. This method first evaluated the coherence of plans of different competences and at different scales within the metropolitan context (trans-scalar evaluation); it then evaluated the interaction between methods and proposals in plans and metropolitan dynamics (interactive evaluation).  相似文献   
29.
30.
Journal of Archaeological Research - The Late Bronze Age (1700–900 BC) represents an extremely dynamic period for Mediterranean Europe. Here, we provide a comparative survey of the...  相似文献   
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