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The 18th century roof tiles from the "Casa delle vigne", located in the Aosta region (north-east Italy), were investigated as an example of a peculiar historical roof covering: ceramic tiles with a lead-based glaze finishing to waterproof them are used to create colourful patterns. A conservation project proposed the integration of the original tiles with new ones, produced according to traditional methods. Ancient and new tiles were analysed with Fiber Optics Reflectance Spectroscopy, micro-Raman, Fourier Transform Infrared Spectroscopy and X-ray Fluorescence Spectrometry, Thermogravimetry and Differential Scanning Calorimetry for understanding the composition and the production technology of this manufacture. Their resistance to freezing and thawing cycles was then tested, considering their exposure in the severe alpine climate of Aosta. The use of pure clays with low calcium contents, high firing temperature and lead-rich glazes was found in ancient tiles, able to outstand several freezing-thawing cycles without damages. Iron and copper pigments were used in old yellow and green glazes. Zinc-based pigment, low lead and calcium-rich glazes are used in the new ones, which remained mainly coherent to the ceramic body during the freeze-thaw test. [ABSTRACT FROM AUTHOR]

Abstract: Stucco samples of the 17th century were collected from the Addolorata Chapel in San Pantalon's church, which represents an important example of the stucco forte technique in Venice. Stucco forte is usually made adding powdered lime and marble to the gypsum base mixture. However, the exact recipe remain in most cases still unknown as often related to the knowledge and experience of the artisans [1]. The aim of the present work is to characterize and study the chemical-physical composition, the working techniques and the conservation state of the stucco forte in Venice. The samples were subjected to optical and electrical microscopic observation (OM, SEM-EDX), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG-DSC), and mercury intrusion porosimetry (MIP). Gypsum, and calcium carbonate were found as major components with presence of magnesium carbonate and traces of hydromagnesite. Magnesite and hydromagnesite do not develop within the normal carbonation processes suggesting that magnesium carbonate was intentionally employed for improving the material characteristics. [Copyright &y& Elsevier]

Thermogravimetry coupled with differential scanning calorimetry (TG-DSC) has been commonly used in the field of conservation of Cultural Heritage for the study of art objects, especially for the characterisation of inorganic matrixes. In recent years, thermal analyses have been applied to the study of organic painting materials. The advantages of performing TG-DSC are linked to the fact that it is micro-destructive technique which does not require any treatment prior the analysis and provide useful information in relatively short time. The aim of this study is to describe the application of TG-DSC on the study of oil binders used in contemporary paints. Even if synthetic binders have become increasingly popular in the 20th century, many contemporary artists still prefer the more traditional media: drying oils. Although the wish of recalling traditional methods, much practical knowledge in paint preparation by mixing drying oil and pigments and in the behaviour of the mixture has been lost. This is mainly due to the different composition of contemporary materials in comparison with the traditional ones and may sometimes lead to different drying properties of the oil paint formulations and consequent problems in the art creation and conservation. For answer to this artistic need and in particular to the difficulties outlined by artists themselves in producing and employing oil paints, unpigmented and pigmented oil films were studied after a week, 1 and 2 years of natural drying under laboratory conditions. Thermal analyses were performed in air flow: the focus of this research was, in fact, to study the thermal and oxidative behaviours of young films for better understanding the very first processes leading to the formation of the film. [ABSTRACT FROM AUTHOR]

The objective of this study was to prepare, characterize and test the catalytic properties of iron and gallium salts of Aquivion ® PFSA (hereinafter Aquivion-H). The samples were characterized by the determination of metal loading in fresh and used materials, ATR-FTIR, and thermogravimetric analysis (TG-DSC). The salts were screened in Friedel–Crafts acylation of some heterocyclic compounds and compared with some homogeneous and heterogeneous Lewis acids as well as with pure Aquivion-H. These new salts revealed efficient catalytic activity and recyclability. [ABSTRACT FROM AUTHOR]