ORMYLIA Foundation

Ormília, Greece

ORMYLIA Foundation

Ormília, Greece

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Sotiropoulou S.,Ormylia Foundation | Papliaka Z.E.,Elettra - Sincrotrone Trieste | Vaccari L.,Elettra - Sincrotrone Trieste
Microchemical Journal | Year: 2016

This work deals with the detection and imaging of metal oxalates/carboxylates in the paint layers of ancient wall paintings and with the investigation of their possible association with the ageing of organic substances used as binding media in the original painting. This assumption is investigated employing Fourier transform infrared (FTIR) imaging on several case studies; starting with a thin section of the paint stratigraphy extracted from extensively deteriorated post-Byzantine murals, painted with an oil binder. Metal carboxylates and oxalates show their maximum concentration at the interface of free fatty acids and pigment particles, indicating a possible origin of their formation. Then, the methodology was applied in paint thin sections, originating from Prehistoric, Roman and Hellenistic wall paintings. In these case studies, metal oxalates detected within the paint layers were explored regarding their relation to the use of an organic binder in the wall paintings. The chemical images of calcium oxalates in the paint layers of the Prehistoric wall paintings was a trigger for further laborious investigation on numerous samples, which resulted in revealing the spectrum of an aged proteinaceous binding medium. Thereafter, the distribution of metal oxalates within the paint layers of the samples from the Roman and Hellenistic wall paintings, unaffected by any later intervention, was assumed as an indirect indication of the use of an original organic binder. © 2015 Elsevier B.V.


Mantzouris D.,Aristotle University of Thessaloniki | Mantzouris D.,Ormylia Foundation | Karapanagiotis I.,Ormylia Foundation | Karapanagiotis I.,Heritage University | Panayiotou C.,Aristotle University of Thessaloniki
Microchemical Journal | Year: 2014

The extractions of indigo (Indigofera tinctoria L.) and safflower (Carthamus tinctorius L.) red and yellow from wool fibres are investigated using high performance liquid chromatography with photo-diode-array detection (HPLC-PDA) which is frequently coupled to Mass Spectrometry (HPLC-PDA-MS) for identification purposes. The efficiencies of dimethyl sulfoxide (DMSO) and dimethyl formamide (DMF) to extract indigo and safflower from wool, are compared for a wide range of temperature (from 40 to 120. °C) and treatment time (from 1 to 30. min). Extraction procedures are investigated by measuring integrated HPLC peak areas of selected dyestuff components, evaluating simultaneously the effects of solvent (DMSO and DMF), treatment temperature (T) and time (t). Thus, cross-influence of the different extraction parameters (solvent, T and t) is taken into account. Indigotin, isatin and indirubin are monitored to evaluate the extraction of indigo. Carthamin, a decomposition product of carthamin, apigenin, safflomin A, 6-hydroxykaempferol-3-O-β-D-glucoside, anhydrosafflor yellow Ct1 and Ct4 are monitored to investigate the extractions of safflower red and yellow. Overall, it is reported that DMSO gives better extraction yields than DMF.The best conditions for the extraction of the marker compounds of the three dyes are summarized as follows. For indigotin, treatments of the wool with DMSO at 80. °C for t. >. 5. min or at 120. °C min for t. = 1. min give the best yield. Longer treatment (t. >. 1. min) at 120. °C results to decomposition of indigotin. For carthamin, treatments of the wool with DMSO at 80. °C for t. >. 5. min or at 120. °C min for short t (<. 5. min) give the best yield, considering that longer (>. 5. min) treatment at 120. °C results to decomposition of the marker compound. Finally, for safflomin A treatments of the wool with DMSO at 100. °C for t. >. 10. min or at 120. °C min for t. = 5. min give the best result. © 2014 Elsevier B.V.


Matziaris K.,Aristotle University of Thessaloniki | Stefanidou M.,Aristotle University of Thessaloniki | Karagiannis G.,ORMYLIA Foundation
Progress in Organic Coatings | Year: 2011

The imperative needs of energy saving during the latest years indicate the necessity of producing hydrophobic building materials in order to increase their durability. In the frame of this experimental work, low-fired clay (roof tiles and facing bricks) have been subjected to impregnation to make them water-repellent. To achieve this, water- and solvent-based silanes/siloxanes have been selected enriched with Si nanoparticles. Generally the mechanism of these coatings is to reduce the water capillary absorption of the building materials which has penetrated, but does not clog pores or capillaries, therefore little or no impairment of the building material's ability to "breathe". Different tests have been performed in the laboratory in order to test the efficiency of the tested solutions such as capillary elevation and water absorption. Additional the measurement and the evaluation of the thickness and the retention of the applied coating on the LFCM were performed using acoustic microscopy. This evaluation can be made in a repetitive way during the lifetime of the material targeting to the continuous monitoring of this effect. © 2011 Elsevier B.V. All rights reserved.


Papadopoulou S.K.,Aristotle University of Thessaloniki | Dritsas G.,Aristotle University of Thessaloniki | Karapanagiotis I.,Ormylia Foundation | Zuburtikudis I.,TEI of Western Macedonia | Panayiotou C.,Aristotle University of Thessaloniki
European Polymer Journal | Year: 2010

A fluorinated methacrylic homopolymer, poly(2,2,3,3,3-pentafluoropropyl methacrylate) (PPFPMA) was synthesized by a free radical polymerization reaction. The dispersive component of the surface energy (γsd) of PPFPMA was determined by contact angle measurements and inverse gas chromatography (IGC). An extensive surface characterization was conducted by means of IGC. Surface characterization demonstrated that PPFPMA has low γsd value, even at 35 °C and is a Lewis amphoteric polymer with predominantly basic character, as confirmed by the Lewis acidity and basicity constants KA and KB, respectively. The values of γsd obtained by IGC are slightly higher than those obtained by the contact angle method. This trend can be attributed to the fact that IGC evaluates, primarily, high energy sites of a surface. © 2009 Elsevier Ltd. All rights reserved.


Papadopoulou S.K.,Aristotle University of Thessaloniki | Karapanagiotis I.,Ormylia Foundation | Zuburtikudis I.,TEI of Western Macedonia | Panayiotou C.,Aristotle University of Thessaloniki
Journal of Polymer Science, Part B: Polymer Physics | Year: 2010

The thermodynamic characterization of a fluorinated methacrylic homopolymer was conducted by means of inverse gas chromatography (IGC), at infinite dilution. The homopolymer under study, poly(2,2,3,3,3-pentafluoropropyl methacrylate) (PPFPMA), was synthesized via a free radical polymerization reaction and was characterized by the employment of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and size exclusion chromatography (SEC) techniques. The specific retention volume of 15 solvents, used as probes, was used for the assessment of the Flory-Huggins interaction parameter, the weight fraction activity coefficient, the molar heat, energy and entropy of sorption, the partial heat of mixing of the probes, as well as the solubility parameter of the polymer. The results demonstrate that PPFPMA is insoluble in most organic solvents even at increased temperatures, with the exception of solvents like 2-Butanone. © 2010 Wiley Periodicals, Inc.


Stefanidou M.,Aristotle University of Thessaloniki | Matziaris K.,Aristotle University of Thessaloniki | Karagiannis G.,ORMYLIA Foundation
Geosciences (Switzerland) | Year: 2013

Modern sustainable architecture indicates the use of local natural stones for building. Greek sandstones from Epirus (Demati, Greece, EN 12440) used as building facades meet aesthetic and have high mechanical properties, but the inevitable interaction between stone materials and natural or anthropogenic weathering factors controls the type, and extent of stone damages. In the present paper, samples of sandstone were treated with a conventional hydrophobic product and four solutions of the same product, enriched with nanosilica of different concentrations. The properties of the treated samples, such as porosity and pore size distribution, microstructure, static contact angle of a water droplet, and durability to deterioration cycles (freeze-thaw) were recorded and conclusions were drawn. The research indicates the increased hydrophobic properties in nanosilica solutions but also the optimum content in nanoparticles that provides hydrophobicity without altering the properties of the stone. © 2013 by the authors; licensee MDPI, Basel, Switzerland.


Stefanidou M.,Aristotle University of Thessaloniki | Matziaris K.,Aristotle University of Thessaloniki | Karagiannis G.,Ormylia Foundation
Geological Society Special Publication | Year: 2016

The protection of Pendelikon marbles to weathering has been the main aim of numerous and longstanding studies. Latest scientific approaches in the field of conservation include methods for self-cleaning surfaces that mimic natural phenomena. In our research, we have critically studied and implemented by means of nanotechnology, the development of a biomimetic composite, protective, hybrid nanostructured film. The mineral substrates have been coated with a fluorosilanic base matrix and furthermore top-coated with a nanostructured synthesis made from amorphous silicon dioxide, sprayed using the 'alla prima' technique. The behaviour of the composite protective coating has been evaluated in terms of wettability, retreatability and resistance to weathering. © 2016 The Geological Society of London.


Grigoriadou I.,Aristotle University of Thessaloniki | Paraskevopoulos K.M.,Aristotle University of Thessaloniki | Karavasili M.,Aristotle University of Thessaloniki | Karagiannis G.,Ormylia Foundation | And 2 more authors.
Composites Part B: Engineering | Year: 2013

In the present study HDPE nanocomposites containing different amounts of copper nanofibers were prepared by melt mixing on a Haake-Buchler Reomixer. From SEM micrographs it was found that there is a fine dispersion of nanofibers into HDPE matrix. Tensile strength at break was unaffected from the addition of nanoparticles and only Young's modulus was enhanced. All nanocomposites in the form of thin films were exposed to UV irradiation at 280 nm for several days. As it was verified from FTIR measurements the mechanism of photo-oxidation consists of macromolecular chain scission, formation of compounds with unsaturated, hydroxyl and carbonyl end groups as well. Also, from FTIR spectroscopy and variation of mechanical properties it was concluded that the addition of Cu-nanofibers enhances the UV stability of HDPE. From acoustic microscopy it was verified that the UV degradation is an oxygen diffusion process and the addition of Cu-nanofibers delays its progress. © 2013 Elsevier Ltd. All rights reserved.


Sotiropoulou S.,Ormylia Foundation | Daniilia S.,Ormylia Foundation
Accounts of Chemical Research | Year: 2010

Holy icons created in the Byzantine era are a vital entity in Orthodox Christianity, a living tradition unbroken over more than 1500 years. The importance of these symbolic representations has inspired interdisciplinary studies to better understand the materials and process of their construction. Researchers from a variety of fields are working together to place icons in their proper historical and cultural framework, as well as to develop long-term conservation strategies. In this Account, we review very recent analytical results of the materials and painting methods used in the production of Byzantine iconography. The care of icons requires particular attention because of their function; icons are objects of veneration and, for the most part, still stand in todays churches to serve ritual practices. Accordingly, they are affected by random, fluctuating environmental conditions aggravated by public access. Because of the holiness of the icons, the typical tradition of the church is to periodically restore the depicted scenes, either by retouching any defects or by partial or complete overpainting. These interventions greatly increase the complexity of the paint stratigraphy. To reveal the extent and quality of the original painting under several historical overpaintings or dirt overlays on the icon, researchers usually pursue a manifold approach, combining complementary multispectral imaging and spectroscopic techniques nondestructively. Unfortunately, a visual and exhaustive spectroscopic examination of a minimum number of cross-sectional microsamples is almost always necessary to clarify the structure of the paint layers and map the constituent materials identified therein. A full understanding of these details is critical for assessing the painting methods, stylistic conventions, and compositional concepts that render the different iconographic details. Cross-sectional micro-Raman spectroscopy, although time-consuming, now affords the direct identification of the distinct grains of almost all of the inorganic pigments and inert components included in the paint layers. Micro-Raman studies are complemented and cross-checked by micro-FTIR and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) studies. This approach is essential in documenting the evolution of the materials and techniques used in creating icons over the centuries. Analytical data on Greek icons are now available for comparison with similar results from other important schools of iconography, such as in the eastern Mediterranean, the Balkans, or Russia, or, further, with Western schools of painting. The research constitutes a reference base for identifying and solving analytical problems, such as those related to the organic materials found in icons that have not yet been systematically studied. Moreover, the results on icons are also generally applicable to important analytical issues encountered in studying any multilayered paint stratigraphies. © 2010 American Chemical Society.


Karapanagiotis I.,Heritage University | Mantzouris D.,Ormylia Foundation | Cooksey C.,59 Swiss Avenue | Mubarak M.S.,University of Jordan | Tsiamyrtzis P.,Athens University of Economics and Business
Microchemical Journal | Year: 2013

The efficiencies of dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), and pyridine to treat and solubilise Tyrian purple are compared using high performance liquid chromatography (HPLC). For the comparative study, samples of Hexaplex trunculus, collected from the area of Carthage, are treated with the three solvents and the following compounds are monitored with HPLC: indigotin, indirubin, 6'-bromoindirubin, 6-bromoindirubin, 6-bromoindigotin, 6,6'-dibromoindigotin and 6,6'-dibromoindirubin. HPLC identifications are achieved as these compounds were synthesized in pure forms and characterized using 1H NMR, elemental analyses and IR spectroscopy. It is shown that pyridine results in poor yields compared to the quantities solubilised using DMF or DMSO. However, the relative composition of the purple dye is not affected by the solvent used for sample treatment. DMSO resulted in improved HPLC signals (peak heights) over DMF and is therefore selected for further studies. The effects of treatment temperature and time are investigated, suggesting that the best conditions correspond to 80°C and 15min.The improved method (treatment with DMSO at 80. °C for 15. min) is used to treat more molluscan samples which are then subjected to HPLC analysis. The results are investigated in the light of previously collected (published and unpublished) analytical data. In particular, principal component analysis (PCA) is applied, to investigate if it is possible to achieve a distinction between the three Mediterranean molluscan species (H. trunculus L., Bolinus brandaris L. and Stramonita haemastoma), using all the HPLC quantitative results reported up until now by various researchers. The PCA plot shows that B. brandaris and S. haemastoma species are not separated and H. trunculus samples are slightly separated from the other two species.The above findings are used to investigate the possible biological origin of Tyrian purple detected in historical -initially studied using X-ray fluorescence spectroscopy- and archaeological samples. Furthermore, the improved method, devised herein, resulted in the identification of monobromoindirubins in the DMSO extracts of the archaeological samples, which were not detected in previous studies where DMF was used to treat the same significant samples. © 2013 Elsevier B.V.

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