1,720,994 research outputs found
Epoxy Resin for the Slope Consolidation Intervention on the Tropea Sandstone Cliff (Southern Calabria, Italy)
No full textThe Tropea cliff (southern Calabria, Italy), affected by fast weathering processes and landslides, has needed various interventions of slope consolidation aimed at reducing hazard conditions. These interventions were performed with low environmental impact techniques in order to preserve the architecture and the landscape of the area. In 1998, a consolidant resin was tested on a limited portion of the Tropea sandstone cliff. The purpose of this test was checking the resin behavior against erosion processes. Previous researches showed a good resistance to erosion with only a slight opacification of the treated sandstone portion. This paper aims at studying the behavior of the consolidant resin after 17 years from its application. The research was performed by several laboratory tests. The Fourier transform infrared spectroscopy analysis has indicated that the consolidant product was an epoxy resin. The scanning electron microscopy analysis has shown that the resin has penetrated into the rock up to 2 mm. The chemical analysis further testified that the tested surface is characterized by higher content of soluble salts than the non-treated surface. The salt content is mainly related to the infiltration of water enriched in soluble salts, due to the marine aerosol. The soluble salts, crystallizing in the rock pores and between the mica sheets, produce an increase of physical stress that is responsible of the exfoliation processes of the resin. Therefore, the use of epoxy resin on the tested sandstone rocks increases the strength on the outer rock surface, with a consequent good resistance to erosion processes just in a restricted period. Overtime, water infiltration introduces dangerous soluble salts below the treated surface, causing salt crystallization with important exfoliation processes of the treated rock surface
Characterisation of ancient mortars from the S. Niccolò archaeological complex in Montieri (Tuscany – Italy)
No full textThe object of the present work is the archaeometric study of the mortars from the S. Niccolo archaeological site in Montieri (Tuscany Italy). The petrographic, mineralogical and chemical characterisation of the samples was obtained by the use of multi-analytical techniques (OM, XRD, SEM-EDS, XRF). The knowledge of the constitutive materials allowed us to understand the different production technologies and highlighted the use of materials with hydraulic behaviour, such as metallurgical slags and cocciopesto. The compositional analogies and differences among the samples contributed to the reconstruction of the building phases, favouring the reading of the history and the evolution of the site over time
Archeologia di un cantiere curtense: il caso del castello di Donoratico (LI) tra IX e X secolo: sequenze stratigrafiche e analisi archeometriche
No full textLe indagini archeologiche svolte nel castello di Donoratico tra il 2000 e il 2010 hanno portato alla luce un’eccezionale sequenza insediativa compresa tra il IV secolo a. C. ed il XV secolo. Particolarmente interessanti le stratigrafie attribuibili al tardo IX secolo, momento in cui furono edificate una cinta difensiva, un ridotto fortificato, una torre e una chiesa, adottando la pietra come materiale da costruzione e l’insediamento, legato al potente monastero di San Pietro in Palazzuolo, assunse notevole rilevanza nelle strategie di controllo e sfruttamento del territorio.
Le caratteristiche del cantiere di costruzione emerse dalla rielaborazione dei dati di scavo e dalle puntuali analisi archeometriche costituiscono uno dei più chiari parametri di lettura per capire il quadro economico e politico di quei decenni, di poco successivi allo sfaldamento del regno carolingio. Le importanti innovazioni tecnologiche adottate, come i tre miscelatori da calce, si spiegano alla luce di un circuito di circolazione di maestranze itineranti con particolari specialismi, probabilmente provenienti anche da territori extra regionali
Petrographic characterization and provenance determination of the white marbles used in the Roman sculptures of Forum Sempronii (Fossombrone, Marche, Italy).
No full textThe Roman municipium of Forum Sempronii (Fossombrone, Marche) was located along the ‘Via Consolare Flaminia’, in the stretch of road where it ran along the final sector of the valley of the River Metauro (Mataurus). The ancient colony of Forum Sempronii, which is cited
by Strabo, Pliny, and Ptolemy, was found in the second century BC, probably on the site of an earlier community and its activity continued until the end of the fifth century AD. During ancient and more recent archaeological excavations, many fragments of coloured stones and marbles, and some white marble sculptures have been unearthed.
In this paper, we report the results of the provenance identification of the white marbles used for the sculptures found in the archaeological site of Forum Sempronii and now displayed at the local archaeological museum. The determination of the source origin of the white marbles used for the sculptures has been established by mineralogical-petrographic and geochemical analyses. Microscopic study of thin sections together with carbon and oxygen stable isotope ratios indicate that more than one type of white marbles was used: Pentelikon, Lunense, and Thasian
Cultural Heritage Documentation and Conservation: Three-Dimensional (3D) Laser Scanning and Geographical Information System (GIS) Techniques for Thematic Mapping of Facade Stonework of St. Nicholas Church (Pisa, Italy)
No full textThis article reports the mapping of the stones, including marbles and brick masonry, used for building the facade of the medieval Church of St. Nicholas (XI century ad), one of the most interesting churches in Pisa, due also to the nearby famous octagonal bell tower. Mapping of stone materials was performed using a computer-aided design (CAD)/geographical information system (GIS) software package for storing and processing spatial information of the ashlars, obtained using three-dimensional (3D) laser-scanning data, combined with high-resolution images, and stone-to-stone observations. Based on collected data, the facade of the Church of St. Nicholas appeared mostly composed of rocks belonging to the metamorphic Tuscan sequence, quartzites, and marbles from Mt. Pisano area. Other types of rocks were also observed, as black limestones quarried at some kilometers northwest from Pisa in the Monti dOltre Serchio area, white Apuan marbles and Macigno sandstones. Conversely, intarsia appeared mainly made up of serpentinite and, subordinately, red limestones laid in white Apuan and Mt. Pisano marbles. © 2016 Taylor & Francis
High‐performing mortar‐based materials from the late imperial baths of Aquileia: An outstanding example of Roman building tradition in Northern Italy
Full text linkThis study provides the first detailed insight into the composition and properties of structural mortars used in a 4th-century AD bath complex in Aquileia, the emblematic center of Roman culture in Northern Italy. Eighteen mortars, taken from different structures of the site, and three stone samples from the vaulting opus caementicium have been analyzed adopting a multianalytical approach integrating optical microscopy, X-ray powder diffraction, X-ray fluorescence, and scanning electron microscopy coupled with energy-dispersive spectroscopy. The properties of the compounds are outstanding, as revealed by the formation of hydraulic phases (i.e., Al-tobermorite and AFm) in most of the samples: the waterproofing capabilities of cocciopesto mortars are remarkable, as revealed by the formation of anthropogenic Al-tobermorite (5.5 wt%) in pool coating samples; the lightweight of the vaults was guaranteed by the use of porous caementa and pozzolanic volcanic aggregates imported from the Gulf of Naples, as demonstrated by petro-mineralogical features and chemical analysis of major and trace elements. This is the first proven case of trade in these building materials to the north of the Italian peninsula. These outcomes shed new light on the robust technical expertise of local artisans in Aquileia and indicate that the Cisalpina province was by no means a peripheral reality in the Roman Empire, as far as mortar-based materials are concerned
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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