首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   124篇
  免费   6篇
  2024年   2篇
  2023年   2篇
  2022年   2篇
  2021年   1篇
  2020年   1篇
  2019年   2篇
  2018年   16篇
  2017年   10篇
  2016年   11篇
  2015年   6篇
  2014年   8篇
  2013年   22篇
  2012年   9篇
  2011年   2篇
  2010年   5篇
  2009年   7篇
  2008年   4篇
  2007年   3篇
  2006年   3篇
  2005年   1篇
  2003年   3篇
  2001年   1篇
  2000年   2篇
  1999年   4篇
  1998年   1篇
  1997年   1篇
  1977年   1篇
排序方式: 共有130条查询结果,搜索用时 15 毫秒
91.
This article focuses on the key role played by Fabio Luca Cavazza, founder of the publishing house Il Mulino, in the development of cultural relations between the US and Italy in the early Cold War by drawing on Cavazza’s personal papers, an as yet unexplored archival source. The Department of State and the Eisenhower administration opposed a government that included the Socialists. However, thanks to the special relationship he had with the ‘New Frontier’s men’, in particular Arthur Schlesinger Jr., Cavazza was able to revive the issue, showing how it was in line with Kennedy’s New Frontier policy.  相似文献   
92.
The measurement of the fineness of debased ancient silver coins has proven to be a very difficult issue, which has been studied for a long time. In this paper, this subject is analysed, and the various consequences of the silver surface enrichment (SSE) are discussed exploiting the most recent investigations. A new model is proposed for the complex object that is an ancient-debased silver coin, based on the silver profiles measured on some sectioned specimens. The model is applied to a sample of 43 coins, mainly Roman victoriati, Cisalpine and Illyrian drachms (from late III to I century B.C.). The coins are investigated in two different ways: neutron diffraction (ND) and specific gravity (SG). The results of the two measurements are combined via the proposed model to provide a more complete numismatic information of the original fineness of the monetary alloy. As a result, a relation between SSE thickness and SG is derived, which, for these coinages, allows to estimate the original alloy silver content from a simple SG measurement; the same method can be used to study other debased coinages, provided that all the procedure (ND and SG) is applied.  相似文献   
93.
We present the detailed analysis of a cervical vertebra from a cave bear, found at Pe?turina cave, Serbia, in a Mousterian archaeological level dated by radiocarbon at 43.5–44.6 kyr cal BP, and by ESR to between 93.5 and 102.5 kyr BP. Identified as a portion of the cranial articular facet, the fragment displays ten subparallel grooves. The microscopic study of these grooves and other surface modification present on the bone fragment, conducted with multifocus optical and confocal microscopes and complemented by a taphonomic analysis of the associated faunal assemblage, supports the hypothesis that the incisions were made by humans. Results are used to critically examine ambiguities implicit in the analysis and interpretation of early engravings, a category of material culture that has been playing a key role in the identification of early instances of symbolically mediated behavior.  相似文献   
94.
The article focuses on the Italian general election held on 4 March 2018, which was notable for the surprising results in southern Italy. These results will be analysed by looking at two dimensions of electoral behaviour: on one hand, participation and volatility, on the other the success of the protest parties, the Five Star Movement (M.5.S.) and the League. These features will be considered in relation to the territorial distribution of the vote. More specifically, in the 2018 election participation was exceptionally high, especially in the south which in some regions saw electors returning to the polls. But electoral volatility is still high. Both factors affected the extraordinary success of new protest parties and collapse of the traditional parties. Traditionally in the south the vote has gone to moderate and pro-government parties, but this time in all constituencies the M.5.S., an ‘eccentric’, protest or populist party-movement, which in many cases took over 40 per cent of the votes, with a peak of 50 per cent in Campania and Sicily. Further, the wave of protest votes favoured another party with no previous support in this geographical area, the League. It may be too soon to say whether these changes in the form and dynamics of the party system are long-lasting and able to achieve a lasting change in the political spectrum, but so far the outcome of election has given a further push to the radicalization of both electoral demand and supply.  相似文献   
95.
96.
Radiocarbon and U-series methods (230Th/U and 231Pa/235U) for absolute age determination have been applied to some fossil samples from Grotta Juntu, in North Eastern Sardinia (Italy). The remains belong to the endemic deer species Praemegaceros cazioti, which is here represented by an almost complete skeleton. The three dating methods lead to concordant ages of about 7500 years BP, indicating that the skeleton was maintained as closed system after burial. Taking into consideration these results, Praemegaceros cazioti from Grotta Juntu is now the youngest representative of this species in Sardinia.  相似文献   
97.
Although 'lake-dwellings' existed from the middle of the fifth millennium to the eighth century BC, the entire phenomenon was not a continuous one. There are several periods when the lake shores were abandoned and subsequently reoccupied. The pattern of occupation depends on cultural as well as environmental factors, amongst them the topography and the climate.
Unlike the southern part of the Alps, which seems to have had a more regular occupational pattern throughout the Neolithic and the Bronze Age, the northern Alpine region shows a marked discontinuity along most of the lake shores. Two relevant breaks in lake-shore occupation are known within the northern Alpine region Bronze Age. The first occurred between the 24th and the 20th centuries BC, and the second from the 15th to the middle of the 12th century BC.
The Early Bronze Age site of ZH-Mozartstrasse, situated on the western extreme of Lake Zurich (Switzerland), was abandoned immediately before the beginning of the second major occupational gap in 1503 BC. Two other Early Bronze Age sites namely Bodman-Schachen 1 on Lake Constance, and Arbon-Bleiche 2 on the Swiss part (the southern shore) of the same lake, follow a similar chronology in occupation; and they were both abandoned in the last decade of the 16th century BC.
A possible cause of abandonment is discussed in this paper using an environmental approach related to an abrupt change of climatic conditions which resulted in an increase of the lake levels which forced those prehistoric populations to leave the proximity of the lake shores. Following the implications of pollen and sedimental analyses, the transformation of the Bronze Age landscape caused by the lake water invasion will be simulated with the help of CAD and GIS computer programs.  相似文献   
98.
Excavations at Acheulean sites in northern Europe at the end of the 19th century have yielded fossil sponges belonging to the Late Cretaceous species Porosphaera globularis. The spherical morphology of these fossils, their small size, and the presence of a natural complete perforation in their center have led some archaeologists to interpret them as the oldest known beads. Others argue that the presence of these fossils at archaeological sites is due to natural processes. Re-examination of material collected during the 19th century has recently revived the bead interpretation. We tested the bead hypothesis by analyzing 13 samples of Porosphaera from nine sites in Britain and France. We conducted morphometric and microscopic analyses on specimens recovered from archaeological sites (n = 349), a natural geological sample, which was collected directly from Cretaceous strata (n = 352), and a sample from a Bronze Age burial (n = 43). Reappraisal of contextual data shows that the association of these finds with Acheulean artifacts is uncertain. Our results show that archaeological specimens are significantly different in size and perforation pattern from those of the natural geological sample. This may be due to size-sorting caused by sedimentary processes, size-selection by Palaeolithic people or by 19th century collectors. Modifications of the fossils' natural shape were detected on a few specimens in the form of localized abrasions and microchipping along the hole margins. A single specimen displays a facet close to the hole produced by grinding. The surfaces of these features exhibit a hue lighter than that observed on the remainder of the specimens indicating that they may be recent in origin and due to post-excavation and preservation treatment. However, this seems contradicted, for some specimens from Bedford, by the fact that according to Smith, W.G. [1884. On a Palaeolithic floor at North-East London. Journal of the Anthropological Institute of Great Britain and Ireland 13, 357–384] the specimens bearing microchipping and abrasions were found by him and “not touched or manipulated by the workmen”. We conclude that new excavations of these sites, involving systematic screening of sediments, are needed in order to attempt to solve the Porosphaera “mystery”.  相似文献   
99.
100.
ABSTRACT

The paper analyzes the static behavior and the seismic vulnerability of the “San Francesco ad Alto” building in Ancona (Italy), which is currently used as a Regional Headquarter of the Marche Region by the Italian Army and was formerly a monastery. The global static structural behavior and the dynamic properties have been evaluated using the Finite Element modeling technique, in which the nonlinear behavior of masonry has been taken into account by proper constitutive laws. The concepts of homogenized material and smeared cracking are used to evaluate the capacity of the monastery to withstand lateral loads together with the expected demands resulting from seismic actions (N2 method), using a nonlinear static analysis (pushover). The comparison of seismic demand and capacity confirms the susceptibility of these types of buildings to extensive damage and collapse, as frequently observed in similar buildings. This paper aims to point out that advanced numerical analyses can offer significant information on the understanding of the actual structural behavior of historical buildings. It is believed that the methodology and the overall conclusions of this case study are valid for many historical monasteries in Europe.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号