1,721,007 research outputs found
Stone Porosity, wettability changes and other features detected by MRI and NMR relaxometry: a more than 15-year study
No full textScientists applying magnetic resonance techniques to cultural heritage are now a quite vast and international community,
even if these applications are not yet well known outside this community. Not only laboratory experiments but also
measurements in the field are now possible, with the use of portable nuclear magnetic resonance (NMR) instruments
that enable non-invasive and non-destructive studies on items of any size, of high artistic and historical value as well
as diagnosis of their conservation state. The situation was completely different in the second half of the 1990s when
our group started working on applications of NMR to cultural heritage, by combining the knowledge of NMR for fluids
in porous media at the University of Bologna, with the skilfulness of the chemists for cultural heritage of CNR and
University of Florence, and Safeguarding Cultural Heritage Department of Aosta. Since then, our interest has been mainly
devoted to develop methods to study the structure of pore space and their changes as a result of the decay, as well as to
evaluate performance of the protective and conservative treatments of porous materials like stone, ceramic, cements and
wood. In this paper, we will review the pathway that led us from the first tentative experiments, in the second half of the
1990s to the current work on these topics
Quantitative Nuclear Magnetic Resonance Imaging, Profiling and Diffusometry on Fluorinated Compounds to Preserve Cultural Heritage Porous Media and Safe for the Environment
No full textThis work was focused on the preparation of a new protective agent with low average
molecular weight containing short pendant perfluoropolyether segments linked to an
oligosuccinamide chain in order to achieve: (i) high hydrophobic effect and photo-stability, (ii)
good adhesion to the rock through the polar amidic groups, (iii) excellent distribution on the pore
walls surface without their blockage, (iv) solubility in environmental friendly solvents.
Hydrophobic penetration and distribution properties of the compound applied on a
biocalcarenite (Lecce stone), have been investigated by Nuclear Magnetic Resonance (NMR)
Imaging, Profiling and Diffusometry of 1H nuclei, and compared with a perfluorinated commercial
product. These NMR techniques has been proved to be a valid non-destructive and non-invasive
technique for monitoring the conservation state and water absorption in materials and objects of
interest to cultural heritage, as well as for evaluating the efficiency and distribution of protective or
consolidation treatments
Traditional buildings for tobacco processing in Val Tiberina (Tuscany-Italy)
Full text linkThis paper focuses on the analysis of buildings devoted to tobacco processing, built in the first half of the 20th century in Tuscany (province of Arezzo), by studying construction techniques, materials, and preservation issues. Since the 16th century, in Tuscany, the sites involved in tobacco cultivation are both the upper Val Tiberina and Val di Chiana (in particular, Arezzo and Siena territories). At first, tobacco was used either for medical purposes or as snuff and pipe powder. It soon became the most renewed cultivation throughout the Tiberina Valley, due to the excellent quality of the tobacco produced. The first significant crops date back to the early 17thcentury. The drying process took place in specific buildings named “tabaccaie”, where tobacco leaves were placed over an oak wood fire to dry. This process was adopted until the 1970s. Subsequently, a profound crisis of the agricultural sector determined the falling into disuse and the abandonment of numerous “tabaccaie”. In some cases, these buildings have been reused as luxury hotels for touristic purposes, but many of them are in a state of ruin or have been demolished. They represent the testimony of agro-industrial vernacular architectures nowadays at significant risk. Indeed, most of the recovery interventions have often wholly obliterated the original structure to make the former “tabaccaie” able to satisfy housing and comfort requests. The study aims to deepen the knowledge of these buildings to preserve cultural identities and transfer inherited values
Rilievo, sperimentazione e monitoraggio programmato per la tutela e conservazione della facciata della Chiesa degli Scalzi a Venezia
No full textIl caso studio del restauro della facciata della chiesa di Santa Maria di Nazareth (meglio conosciuto come chiesa degli Scalzi) a Venezia rappresenta un’innovativa e fruttuosa collaborazione interdisci-plinare. Essendo posta all’ingresso della città lagunare, la chiesa già da fine Ottocento rappresenta un landmark segnando in maniera decisa la facies urbana della città di Venezia. La facciata barocca, realizzata sul progetto di Giuseppe Sardi tra il 1672 e il 1680, rappresenta un unicum a Venezia in quanto interamente realizzata in marmo di Carrara, un calcare a struttura saccaroide che si è dimostra-to nei secoli inadatto all’aggressivo clima lagunare. Nel corso dei secoli sono stati necessari diversi interventi di restauro, l’ultimo dei quali tra il 2014 e fine 2018 a seguito della caduta di una foglia d’acanto di un capitello nell’estate 2013. Le indagini diagnostiche hanno portato alla luce un vasto e inaspettato fenomeno degenerativo che ha interessato l’intero apparato decorativo. È stata quindi intrapresa una ricerca sperimentale sia dal punto di vista del rilievo metrico e formale, inteso come operazione necessaria alla conoscenza del monumento, sia dal punto delle tecnologie e delle tecniche di consolidamento effettuate nei secoli.
Data la complessità della facciata, le operazioni di rilievo, svolte con le metodologie più innovative, sono state fondamentali per acquisire una profonda conoscenza dell’intero manufatto, importante rife-rimento su cui impostare la campagna di monitoraggio, ma anche utile a pianificare futuri interventi di manutenzione.
Il principio costitutivo del progetto di restauro della facciata si è orientato verso l’impiego di materiali e di tecnologie costruttive tradizionali con l’abbinamento di materiali innovativi, come l’impiego di na-notecnologie per l’intervento di consolidamento. A partire quindi da una verifica puntuale, garantita da una sperimentazione accurata e da un attento monitoraggio, si è voluto perseguire l’obiettivo di un re-stauro conservativo efficace, compatibile e ritrattabile e capace di consentire il controllo dell’efficacia degli interventi nel futuro.
The case study of the façade restoration of the Church of Santa Maria di Nazareth (better known as the Church of the Scalzi) in Venice epresents an innovative and fruitful interdisciplinary collaboration. Being located at the entrance to the lagoon city, the church has been a landmark since he late nineteenth century, decisively marking the facies urbana of Venice. The baroque façade, built on the project by Giuseppe Sardi between 1672 and 1680, is unique in Venice as it is entirely made of Carrara marble, a limestone with a saccharoid structure that over the centuries has proved unsuitable for the aggressive lagoon climate. Over the centuries, several restoration interventions have been necessary, the last of which between 2014 and the end of 2018, following the fall of an acanthus leaf from a capital in the Summer 2013. The diagnostic investigations have brought to light a wide and unexpected degenerative phenomenon that has affected the entire decorative apparatus. An experimental research
was therefore undertaken both from the point of view of the metric and formal survey, intended as an operation necessary for the knowledge of the monument, both from the point of view of technologies and consolidation techniques carried out over the centuries.
Given the complexity of the façade the survey operations, carried out with the most innovative methodologies, have been essential to acquire a deep knowledge of the entire building. Knowledge that constituted an important reference on which the monitoring campaign has been set up and that will be useful for planning future maintenance interventions.
The leading principle of the façade restoration project is oriented towards the use of traditional construction materials and technologies with the combination of innovative materials, such as the use of nanotechnologies for the consolidation intervention. Beginning with an in-depth check, guaranteed by careful experimentation and thorough monitoring, the authors wanted to pursue the goal of an effective, compatible and retractable conservative restoration, capable of allowing in the future the control of the interventions effectiveness
Two 1H-NMR methods to measure internal porosity of bone trabeculae: by solid-liquid signal separation and by longitudinal relaxation
No full textNon-invasive and Micro-invasive Investigations on Wall Paintings from a XIII century Temple in Bagan Valley (Myanmar)
No full textOn August 24, 2016, a magnitude 6.8
earthquake struck central Myanmar, seriously
damaging and partially destroying more than 300
structures in Bagan Archaeological Zone.
Department of Archaeology, UNESCO Bangkok
Office and Japan International Cooperation Agency
collected information about the damage to the
cultural heritage caused by the earthquake.
In February and July 2017, a scientific survey
concerning XIII centuries wall paintings of temple
Me-taw-ya, located in the south of Myinkaba village
in Bagan site, carried out. It was supported by Tokyo
National Research Institute for Cultural Properties
(TNRICP).
As a part of a previous project, preliminary
investigations were carried out to acquire information
on constitutive materials and construction technology
of wall paintings.
The conservation state of wall paintings and the
presence of non-original materials were also
investigated.
The goal of the present study is to obtain appropriate
technical scientific information to draw up a
“practical code” to be adopted in wall paintings
restoration
Calcium antimonate: A new discovery in colour palette of Paestum wall paintings
No full textDuring a restoration and diagnostic campaigns carried out on Paestum funerary slabs belonging to the Lucanian funerary art, calcium antimonate (CaSb2O6) was detected for the first time in the pictorial layers. This artificial pigment, widely employed as opacifier both in ancient glass and glaze covering clay objects, was found in the wall paintings, regardless of the colour, supporting the hypothesis of an intentional addition of calcium antimonate to the pigments and the involvement of ceramic painters. A multi-analytical approach was performed on 32 funerary slabs (6th-3rd century BCE), currently located at the National Archaeological Museum of Paestum (Italy) using both polarized light microscopy and environmental scanning electron microscopy equipped with energy dispersive X-ray spectrometer, micro X-ray fluorescence, micro Raman spectroscopy, Fourier Transform Infrared spectroscopy and powder X-ray diffraction. The results confirmed the use of a limited number of pigments, usually applied with fresco technique, although in many cases the stratigraphy of the painted layer showed morphology of mezzo fresco technique, but no organic binders were found. The hues of vegetal decorations were obtained using green earth, sometimes Egyptian blue mixed with yellow ochre, carbon and bone blacks, and orpiment. The alteration of green earth and other ironcontaining pigments are likely responsible for the discolouration of the original hues. In red paints, hematite and red ochre are frequently associated with ilmenite, a typical volcanic mineral. Egyptian blue was used in blue paints while in black paints it was mixed with carbon and bone black pigments
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
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