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Sandu I.C.A.,University of Evora | Hayashi M.,National Research Institute of Cultural Properties | Vasilache V.,Al. I. Cuza University | Cozma D.-G.,Al. I. Cuza University | And 3 more authors.
Revista de Chimie | Year: 2015

This study presents the data regarding the influence of two organic solvents (ethylic alcohol and Red Petroleum from Campeni), mixed with bee propolis, on different wood essences. The impact of these systems was evaluated by studying several physical-structural dynamic characteristics of the treated samples. The shrinkage of lime, poplar, fir and oak wood was studied on three sections (longitude - L, tangential - T and radial-R), for four different variations of atmospheric humidity (100,85,65,25%RH), by gradually lowering the value (100%->85%, 85%->65%, 65%->25% and 25%->0%). In order to evaluate the impact of the treatment, two chemometric characteristics were taken into consideration: Difference of shrinkage (ΔL, ΔR and ΔT) and the ratio of those differences (ΔT/ΔL, ΔT/ΔR and ΔR/ΔL). At the end of the paper, the volumetric shrinkage vas studied, alongside with the density and porosity variations of the wood. In order to evaluate the impact of these systems several chemometric characteristics were used: ΔV, Δρ and Δp. The obtained results have shown that poplar tree is virtually unaffected by the two treatments, the lime tree is slightly in fluenced, while the fir tree and oak tree are the most affected, because the used solutions easily dissolve their organic components. These components leave the resinous channels and pores of the oak tree, thus changing the specific weight and porosity. After the dissolution of the organic components present in natural wood, these solutions create a nano-coating on the surface of the anatomical elements, which confer detectable behaviours only to the wood species containing volatile components that are not compatible with the studied organic solutions. The behaviours can be detected during the interactions of the above mentioned wood species with the hygroscopic moisture in the atmosphere. Source

Hutanu I.,Al. I. Cuza University | Sandu I.,Al. I. Cuza University | Simionescu A.-E.,George Enescu University of Artes | Vasilache V.,Al. I. Cuza University | And 2 more authors.
Revista de Chimie | Year: 2015

The first intervention realized in the case of art works with a precarious state of conservation is the consolidation of support and superficial layer. Generally for the puzzle-like painting layer the preventive consolidation is an urgent intervention, which will be followed, after a succession of interventions, by a definitive one. Furthermore, if the polychrome layer is pulverous, the binder will be applied over the entire degraded surface. In both of cases, the binder can damage the polychromy and gildings. For this purpose, this paper studies the influence of acrylic binders upon gildings with gold leaf and schlagmetal, respectively the manner in which these binders are applied and the effects they have upon them. For the experiments there were used samples of fir tree gilded with gold or schlagmetal or other imitative products that are on the market. After gilding the samples were coated with acrylic binders and put in the oven, for artificial ageing. The analysis were realized with optical microscope, SEM-EDX and spectrophotometer in CIE L∗a∗b∗ system. Source

Cristache R.A.,Al. I. Cuza University | Sandu I.C.A.,University of Evora | Simionescu A.E.,George Enescu University of Artes | Vasilache V.,George Enescu University of Artes | And 2 more authors.
Revista de Chimie | Year: 2015

This paper presents a physico - chemical study of the paint layers of "Saint Nicholas" icon, which comes from a private collection in Romania. The icon has artistic characteristics of the Russian icons, the Post-Byzantine style, and is an expression of the painted art in the Orthodox Church. Significant information about the icon painting technique, the materials used and about the period in which the icon was made, were found using new analytical techniques. The aim of this study is to gather useful information about the icon to make a suitable conservation and restoration treatment of the artifact. For the analysis of the icon's materials (preparation layer, paint layer and varnish), Optical Microscopy (OM), scanning electron microscopy connected with X-ray spectrometry (SEM-EDX) and Fourier transformed infrared spectrophotometry (ju-FTIR), were used. It was concluded that the paint layer is made of tempera (pigment with egg-based emulsion), painted over silver leaf, over which olifa varnish was used. Based on the style of the painting and on its conservation state, it is presumed that it was painted in the XIXth century. The corroboration between the analytic data, highlighted different details of the painting process and of the used materials. Thus, mineral pigments, colored earths, silver leaf and paper stripes under the gesso were identified. Source

Vasilache V.,Al. I. Cuza University | Sandu I.C.A.,University of Evora | Pruteanu S.,Al. I. Cuza University | Caldeira A.T.,University of Evora | And 2 more authors.
Applied Surface Science | Year: 2016

Adherent deposits are very aggressive towards ancient heritage paintings since they affect the varnish and the painting's layers, sometimes reaching the preparative layers. The biggest problem to the restorer is their removal without affecting the patina, the transparent varnish (well preserved) and fine colour glazes made during painting. Therefore, their removal requires preliminary cleaning tests that allow the optimization of the cleaning system composition that is going to be used. The study was focused on organic natural systems, as colourless supernatants, some of them used during ages, but insufficiently studied. The paper presents an evaluation of the effectiveness of cleaning varnished icons of the nineteenth century, with complex conservation cases using supernatants derived from aqueous dispersions extracted from vegetables and dry indigenous herbal infusions. Best results, after six consecutive cleaning steps, on tempera old icon was obtained for a mixture made of mature white onion juice + extract of Soapwort flowers + corn silk tea + acacia tea. As a best result after just one cleaning step was obtained for a quaternary mixture composed from mature white onion juice + mature carrot juice + corn silk tea + aqueous extract of Soapwort flowers. © 2016 Elsevier B.V. All rights reserved. Source

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