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Vienna, Austria

The Academy of Fine Arts Vienna is a public art school of higher education in Vienna, Austria. Wikipedia.

Hobro A.J.,Vienna University of Technology | Kuligowski J.,University of Valencia | Doll M.,Austrian Academy of Fine Arts | Lendl B.,Vienna University of Technology
Analytical and Bioanalytical Chemistry

Wood is a ubiquitous material used in everyday life. Accurate identification of species can be of importance in a historical context enabling appropriate conservation treatment and adequate choice of material to be applied to historic wooden objects, and in a more modern context, in the identification of forgeries. Wood is also often treated to improve certain physical characteristics, often strength and durability. However, determination of whether or not a piece of wood has been treated can be very difficult. Infrared spectroscopy has previously been applied to differentiate between different wood species or between treated and untreated wood, often in conjunction with chemometric analysis techniques. Here, we report the use of mid-IR spectroscopy, coupled with partial least squares discriminant analysis for the discrimination between two walnut wood species and to differentiate between steamtreated and untreated samples of each of these wood species. We show that the discrimination between species and between steam-treated and non-steam-treated wood from Juglans nigra is very clear and, while analysis of the quality of the discrimination between steam-treated and non-steam-treated J. regia samples is not as good, it is, nevertheless, sufficient for discrimination between the two groups with a statistical significance of P<0.0001. © Springer-Verlag 2010. Source

Martina I.,Austrian Academy of Fine Arts | Martina I.,University of Padua | Wiesinger R.,Austrian Academy of Fine Arts | Schreiner M.,Austrian Academy of Fine Arts | Schreiner M.,Vienna University of Technology
Journal of Raman Spectroscopy

Silver is a soft, lustrous metal with the highest electrical and thermal conductivity. Due to these properties, it has many applications as a precious material both in pure and alloy form (ornaments, jewellery, utensils, coins), but also in several technological fields, considering silver compounds (e.g. photography, electric and electronic industry). As a consequence of this, silver and its by-products are regularly exposed to different atmospheres where a wide spectrum of agents (e.g. moisture, temperature, air pollutants, UV light) may cause metal corrosion and alteration of their surface characteristics and properties. The aim of this research is to deepen the potential and applicability of micro-Raman spectroscopy as a surface-sensitive technique to investigate the initial steps of atmospheric corrosion throughout the identification of surface chemical reactions and corrosion products formed on silver substrates. In a previous study, micro-Raman analysis was carried out on pure silver powder compounds, selected among the most expected corrosion products occurring on silver substrates, in order to optimize experimental conditions and to obtain reference spectra [1]. Subsequently highly pure silver samples were exposed for 24 h to different controlled laboratory atmospheres (synthetic air, relative humidity, SO2, H2S), particularly focusing on sulfur containing gases, and the resulting surface reactions. The experiments highlight micro-Raman spectroscopy as a highly surface-sensitive technique enabling to detect both adsorbed chemical species and crystalline corrosion products of only several monolayers of thickness. Furthermore, these investigations could show the trends of primary and secondary corrosion mechanisms and their mutual interaction occurring on silver substrates. Copyright © 2013 John Wiley & Sons, Ltd. Source

Wiesinger R.,Austrian Academy of Fine Arts | Martina I.,Austrian Academy of Fine Arts | Kleber C.,Austrian Academy of Fine Arts | Kleber C.,CEST Center Of Electrochemical Surface Technology | And 2 more authors.
Corrosion Science

The interaction of highly pure polycrystalline silver samples with ozone (500ppb) was investigated under certain relative humidity (RH) content (0%, 50% and 90%) in synthetic air. All experiments were performed at room temperature (22°C) and atmospheric pressure. Highly surface sensitive methods were used to investigate chemical, morphological and structural changes and composition of the corrosion products formed at different RH and reaction times. Silver is oxidized by ozone forming Ag2O/AgO(AgIAgIIIO2) surface species. The oxide formation and corrosion rate is dependent on the RH content in the atmosphere, showing that silver is most susceptible to ozone oxidation at 50% RH. © 2013 Elsevier Ltd. Source

De Bardi M.,Vienna University of Technology | De Bardi M.,Austrian Academy of Fine Arts | Hutter H.,Vienna University of Technology | Schreiner M.,Vienna University of Technology | Schreiner M.,Austrian Academy of Fine Arts
Applied Surface Science

In this work the durability to acidic solutions of two kinds of potash-lime-silica glasses with compositions typical for mediaeval stained glass was investigated. The low amount of network formers such as silica and alumina, and the high amount of network modifiers such as potassium and calcium, give to the glass a lower chemical stability compared to modern glass. Studies on its durability are of interest to understand degradation mechanisms. In particular the leaching procedure was focused on determining any correlation between the type of acid and the corrosion of glass independently from the pH value, which was kept constant during the different acidic treatments. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a valuable tool to study compositional variations of glass, giving useful information concerning provenance, effects of the conservation environment, of weathering or leaching processes and about the compositional differences between the corroded layer and the bulk as a function of depth. In spite of that the insulating properties of glass, the surface roughness and the parameters used for the measurements can lead to possible misinterpretations of the results; in this paper these difficulties are discussed, in order to better interpret the analyses performed on leached glass. ToF-SIMS data are influenced by strong matrix effects making quantification difficult; for this reason the quantitative composition and surface morphology of the leached layer were additionally investigated with scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM-EDX). © 2013 Elsevier B.V. All rights reserved. Source

Pintus V.,Vienna University of Technology | Pintus V.,Austrian Academy of Fine Arts | Schreiner M.,Vienna University of Technology | Schreiner M.,Austrian Academy of Fine Arts
Analytical and Bioanalytical Chemistry

This study characterizes and identifies two different acrylic binding media such as Plextol® D498 and Primal® AC33, which are widely used in modern and contemporary art. In order to investigate their fast photooxidative deterioration when exposed to ultraviolet (UV) light, ageing studies on these materials were carried out. For this purpose, pure synthetic materials but also mixed with different inorganic pigments were identified and characterized before and after UV exposure by means of pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Particular attention was paid to the comparison of two different analytical methods: (1) single-shot method based on a pyrolysis for the analysis of polymers and (2) double-shot method, which allows a unique combination of thermal desorption for the analysis of volatile compounds and pyrolysis of the polymers themselves. These analyses have been complemented by Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) studies. The comparison of the results obtained from unaged samples and UV-aged clearly showed material alterations as well as the formation of new products, which were recorded by FTIR-ATR. Generally, these changes were more pronounced when the acrylic binding media were mixed with pigments. The double-shot technique of Py-GC/MS additionally allowed the detection of the phenolic antioxidant in unaged Plextol® D498, but no oxidation products could be identified by Py-GC/MS in all samples. © Springer-Verlag 2010. Source

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