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1.
We exploit a recent generalization of the Thrust Network Analysis (TNA) to analyse masonry structures of extremely complicated and audacious geometry such as helicoidal staircases. Actually, differently from available methods, based on ad-hoc solutions holding for each particular structure, the TNA allows for studying the equilibrium of structures of arbitrary shape by invoking the principles of limit analysis of masonry structures dictated by Heyman. Four paradigmatic monumental staircases, with increased degree of complexity, have been selected as case studies in order to show the versatility and accuracy of the proposed approach. The results entailed from the generalized TNA are also successfully compared, for the first time in the literature, with those related to the adoption of available analytical methods for the analysis of no-tension membranes.  相似文献   
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This article analyses, adopting the well-known approach of Katz and Mair, the issue of organizational change within Italian political parties since 1990. In addition to an account of trends in membership, local units, finances, staff, and of changes in party statutes, the article aims at testing the widespread view in the literature that organizational resources–hence power–are becoming more and more concentrated in the hands of party and/or parliamentary leaders, and correspondingly that the territorial presence of parties is declining. The analysis of the change over time of Katz and Mair's party organisational ‘faces’ leads to the confirmation, to a large extent, of the overall hypothesis of a decline of the party at ground level, and a concentration of party resources in the central office, and above all in the party in public office.  相似文献   
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The aim of this work was to detect imprints on soil properties from former Islamic land use (9th to 11th century) using a multi-method, soil-chemical approach. Four soil profiles (with buried horizons) found in the vicinities of former Islamic settlements in Sicily were analysed for phosphorus (total, organic and inorganic), nitrogen (total, NO3 and NH4+), carbon compounds (δ13C, lipids, polycyclic aromatic hydrocarbons (PAH) and functional groups), physical and chemical C-fractions and the state of soil weathering. Two soil profiles contained ceramic sherds from the Islamic period. Inorganic nitrogen forms, phosphorous and the PAH content indicated strong impacts from traditional agriculture and/or burning. Radiocarbon dating of soil organic carbon (SOC) fractions from buried horizons showed that distinct changes must have occurred during the Islamic epoch. The isotopic composition of SOC indicated that land use was probably different in earlier times. C4 plant cultivation was expected but surprisingly lipid analyses did not confirm this. A high amount of aliphates and low C/N ratio indicated a good, long-term SOC stabilisation under the native conditions combined with Islamic land use. The irrigation of the soils probably increased the production of weakly-crystalline Fe forms that helped to stabilise SOC.  相似文献   
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Scavenger birds can feed on large- to small-sized vertebrates and may contribute in the formation of archaeological sites. To evaluate the modifications and dispersal patterns of bones produced by New World vulture and caracara from Northwestern Patagonia, samples of adult sheep, young sheep, and hare carcasses were offered and subsequently analyzed. New World vultures and caracaras quickly fed on the samples. Taphonomic and bone dispersal patterns suggest two types of accumulations: (1) open-air sites with large and medium-sized vertebrates represented by complete, fractured, scratched, notched, and punctured elements and (2) rock shelter or cave sites dominated by small vertebrates represented by broken, corroded, fractured, and digested elements.  相似文献   
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According to a number of influential Italian contemporary historians, Italian political history since Unification has been distorted by politicized scholarship and the existence of a large number of untenable political myths. These views are presented in the volume Miti e storia dell'Italia unita (1999). In this roundtable, Ruth Ben-Ghiat, Carl Ipsen and David Kertzer discuss this thesis with two of its leading proponents: Ernesto Galli della Loggia and Luciano Cafagna. Secondo alcuni studiosi dell'Italia contemporanea, la storiografia dell'Italia unita è stata travisata dalla tendenza a scrivere testi politicizzati e dall'esistenza di numerosi miti politici infondati. In questa tavola rotonda, Ruth Ben-Ghiat, Carl Ipsen e David Kertzer discutono le tesi proposte nel volumi Miti e Storia dell'Italia Unite 1999 (Bologna, Il Mulino) con due suoi sostenitori: Ernesto Galli della Loggia e Luciano Cafagna.  相似文献   
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Bittencourt, J.S., Leal, L.A., Langer, M.C. & Azevedo, S.A.K., June 2012. An additional basal sauropodomorph specimen from theUpperTriassic Caturrita Formation, southern Brazil, with comments on the biogeography of plateosaurids. Alcheringa, 1–10. ISSN0311-5518.

We describe an additional saurischian specimen from the Caturrita Formation (Norian) of the Parana Basin, southern Brazil. This material was collected in the 1950s and remained unstudied due to its fragmentary condition. Detailed comparisons with other saurischians worldwide reveal that some characters of the ilium, including the low ventral projection of the medial wall of the acetabulum and its concave ventral margin, together with the short triangular shape of the pre-acetabular process and its mound-like dorsocaudal edge, resemble those of sauropodomorphs such as Plateosaurus and Riojasaurus. This set of traits suggests that MN 1326-V has affinities with basal Sauropodomorpha, probably closer to plateosaurians than to Saturnalia-like taxa. Previous records of this clade in the Caturrita Formation include Unaysaurus, which has been related to Plateosaurus within Plateosauridae. Alternative schemes suggest that plateosaurids include Plateosaurus plus the Argentinean ‘prosauropods’ Coloradisaurus and Riojasaurus. Both hypotheses raise biogeographic questions, as a close relationship between faunas from South America and Europe excluding Africa and North America is not supported by geological and biostratigraphical evidence. Additionally, the absence of plateosaurids in other continents suggests that the geographical distribution of thistaxon is inconsistent with the geological history of western Pangaea, and this demands further investigations of the phylogeny of sauropodomorphs or improved sampling.

J.S. Bittencourt* [sigmaorionis@yahoo.com.br] Laboratório de Paleontologia, Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 1404901, Ribeirão Preto, SP, Brazil. Fellow FAPESP; L.A. Leal, Departamento de Ciências Biológicas, Universidade Estadual do Sudoeste da Bahia, Rua José Moreira Sobrinho, s/n, 45206-190, Jequié, BA, Brazil; M.C. Langer, Laboratório de Paleontologia, Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 1404901, Ribeirão Preto, SP, Brazil; S.A.K. Azevedo, Laboratório de Processamento de Imagem Digital, Departamento de Geologia e Paleontologia, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista s/n, 20940-040, Rio de Janeiro, RJ, Brazil. Received 29.7.2011; revised 10.10.2011; accepted 18.10.2011.  相似文献   
9.
The determination of the chemical composition of different parts of wall paintings (pigments, mortars and binders) provides information about technology of preparation of an artefact. Herein, we present a multi-methodological characterisation of wall paintings from a Roman archaeological site in Cuma, focusing on differences between an indoor (domus) and outdoor fabrication (a temple, Tempio con Portico (TCP)). Both pigments, binders and mortars were studied via a combination of destructive/μ-destructive (mass spectrometry, ionic chromatography, ICP-based techniques) and non-destructive (Raman microscopy, small-angle neutron scattering (SANS) and X-ray diffraction) methodologies. Particularly, the systematic presence of dolomite only in mortars from TCP may suggest an intentional use of such limestone for the outdoor fabrication of public interest. Differences between TCP and domus are also related to the composition of the pigment binder. In particular, the detected binders (studied by LC-MS/MS and GC-MS) were proteinaceous in the case of domus (possibly egg and animal glue) and drying oils in the case of TCP. Ultimately, our multi-methodological study provides an overall picture of the material components of paintings from fabrications with different use, proposing a hypothesis on technological choices according to conservative and destination reasons.  相似文献   
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