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Paper bookbindings have been disregarded for centuries by scholars since they were only considered temporary covering materials for manuscripts and books. Recently, there is a willingness to reconsider these bindings and to evaluate their role. Thanks to the collaboration with the Marciana National Library in Venice, which stores an impressive collection of 849 detached bindings, the current research provides a chemical-physical elucidation about the composition and the manufacture of paper bookbindings realized between the 16th and the eighteenth century in the Venetian area. A selection of bookbindings was analysed by the means of complementary methods (thickness measurements, Attenuated Total Reflection—Fourier-Transform Infrared Spectroscopy (ATR-FTIR), Pyrolysis–Gas Chromatography–Mass Spectrometry (Py-GC–MS) and X-Ray Fluorescence (XRF)). Data evidence the presence of cellulose as the main component of paper pulp; hemicellulose and lignin were identified too, probably related to the presence of linen/hemp rags in the paper production. Gelatine was detected muck likely related to paper sizing; among inorganic additives CaCO3 was found in all samples. The presence of waxy material may be due to past undocumented conservation treatments. [ABSTRACT FROM AUTHOR]

The combination of the ability to absorb most of the solar radiation and simultaneously suppress infrared re-radiation allows selective solar absorbers (SSAs) to maximize solar energy to heat conversion, which is critical to several advanced applications. The intrinsic spectral selective materials are rare in nature and only a few demonstrated complete solar absorption. Typically, intrinsic materials exhibit high performances when integrated into complex multilayered solar absorber systems due to their limited spectral selectivity and solar absorption. In this study, we propose CoSbx (2 < x < 3) as a new exceptionally efficient SSA. Here we demonstrate that the low bandgap nature of CoSbx endows broadband solar absorption (0.96) over the solar spectral range and simultaneous low emissivity (0.18) in the mid-infrared region, resulting in a remarkable intrinsic spectral solar selectivity of 5.3. Under 1 sun illumination, the heat concentrates on the surface of the CoSbx thin film, and an impressive temperature of 101.7 °C is reached, demonstrating the highest value among reported intrinsic SSAs. Furthermore, the CoSbx was tested for solar water evaporation achieving an evaporation rate of 1.4 kg m−2 h−1. This study could expand the use of narrow bandgap semiconductors as efficient intrinsic SSAs with high surface temperatures in solar applications. The efficiency of CoSbx (where 2 < x < 3) as a selective solar absorber is investigated. Here, authors demonstrate that CoSbx endows broadband solar absorption (0.96) and simultaneous low emissivity (0.18), making it a promising material for use in solar energy systems. [ABSTRACT FROM AUTHOR]

In this work, we present the results of the analysis of the indoor behavior of temperature and relative humidity in the space of temporary exhibitions of the Gallerie dell'Accademia Museum in Venice (Italy), located in the ancient Santa Maria della Carità Church. The museum was monitored from May to October 2019 during the exhibition "Baselitz-Academy". This research analyzed the microclimate using a tailored methodology for the study of indoor climate in historical buildings." This methodology is based on the calculation of daily and weekly fluctuations, as well as the speed of weekly fluctuations in temperature and relative humidity. Additionally, the microclimate in the monitored rooms were compared by calculating the indices of climate excursions (ICE) for each type of fluctuation. In the Santa Maria della Carità church, the analysis shows that the current use of an adapted air conditioning system plus the hygrothermal inertia of the building ensures a stable ambience, appropriate for the conservation needs of fragile artworks with little fluctuations. [ABSTRACT FROM AUTHOR]

Although in many cases Pb isotopic analysis can be relied on for provenance determination of ancient bronzes, sometimes the use of 'non-traditional' isotopic systems, such as those of Cu and Sn, is required. The work reported on in this paper aimed at revising the methodology for Cu and Sn isotope ratio measurements in archaeological bronzes via optimization of the analytical procedures in terms of sample pre-treatment, measurement protocol, precision, and analytical uncertainty. For Cu isotopic analysis, both Zn and Ni were investigated for their merit as internal standard (IS) relied on for mass bias correction. The use of Ni as IS seems to be the most robust approach as Ni is less prone to contamination, has a lower abundance in bronzes and an ionization potential similar to that of Cu, and provides slightly better reproducibility values when applied to NIST SRM 976 Cu isotopic reference material. The possibility of carrying out direct isotopic analysis without prior Cu isolation (with AG-MP-1 anion exchange resin) was investigated by analysis of CRM IARM 91D bronze reference material, synthetic solutions, and archaeological bronzes. Both procedures (Cu isolation/no Cu isolation) provide similar δCu results with similar uncertainty budgets in all cases (±0.02-0.04 per mil in delta units, k = 2, n = 4). Direct isotopic analysis of Cu therefore seems feasible, without evidence of spectral interference or matrix-induced effect on the extent of mass bias. For Sn, a separation protocol relying on TRU-Spec anion exchange resin was optimized, providing a recovery close to 100 % without on-column fractionation. Cu was recovered quantitatively together with the bronze matrix with this isolation protocol. Isotopic analysis of this Cu fraction provides δCu results similar to those obtained upon isolation using AG-MP-1 resin. This means that Cu and Sn isotopic analysis of bronze alloys can therefore be carried out after a single chromatographic separation using TRU-Spec resin. Tin isotopic analysis was performed relying on Sb as an internal standard used for mass bias correction. The reproducibility over a period of 1 month ( n = 42) for the mass bias-corrected Sn isotope ratios is in the range of 0.06-0.16 per mil (2 s), for all the ratios monitored. [ABSTRACT FROM AUTHOR]

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]