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Author Radepont, M.; Coquinot, Y.; Janssens, K.; Ezrati, J.-J.; de Nolf, W.; Cotte, M. url  doi
openurl 
  Title Thermodynamic and experimental study of the degradation of the red pigment mercury sulfide Type A1 Journal article
  Year (up) 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 30 Issue 3 Pages 599-612  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The red pigment mercury sulfide, called cinnabar or vermilion, is well known to suffer from an alteration giving rise to a grey, grey-white or black color at the surface of degraded works of art. This phenomenon can dramatically affect the esthetical value of artworks. This work aims at assessing the factors (light, halides) influencing the instability of red mercury sulfide and understanding (by combining thermodynamic and experimental approaches) the chemical equilibria governing the formation and evolution of the different degradation compounds. From the thermodynamic study of the Hg-S-Cl-H2O system, it was concluded that Hg(0), Hg3S2Cl2, and Hg2Cl2 can be formed from the reaction of alpha-HgS with ClO(g). In the second part, the artificial ageing experiments presented were carried out on model samples following the conditions assessed in the first part, in order to reproduce natural ageing observed on red mercury sulfide. Similarly to degradation compounds detected on original works of art, mercury chlorine compounds such as calomel (Hg2Cl2) and corderoite (alpha-Hg3S2Cl2) were identified on the surface of alpha-HgS model samples, when exposed to light and a sodium hypochlorite solution. Sulfates were detected as well, and more particularly gypsum (CaSO4 center dot 2H(2)O) when Ca was originally present in the model sample. The relationship between color and composition is discussed as well.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000350650800005 Publication Date 2015-01-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 26 Open Access  
  Notes ; The authors gratefully acknowledge the ESRF for granting beamtime under proposal no. EC720. Michel Dubus is thanked for providing precious advices concerning ageing protocols. This research was supported by Belgian Science Policy project S2-ART (BELSPO S4DA), the GOA “SOLARPAINT” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects no. G.0C12.13, G.0704.08 and G.01769.09. ; Approved Most recent IF: 3.379; 2015 IF: 3.466  
  Call Number UA @ admin @ c:irua:125474 Serial 5877  
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Author Aghaei, M.; Bogaerts, A. url  doi
openurl 
  Title Particle transport through an inductively coupled plasma torch: elemental droplet evaporation Type A1 Journal article
  Year (up) 2016 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 31 Issue 31 Pages 631-641  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract We studied the transport of copper droplets through an inductively coupled plasma, connected to the sampling cone of a mass spectrometer, by means of a computational model. The sample droplets are followed until they become evaporated. They are inserted as liquid particles from the central inlet and the effects of injection position (i.e. “on” and “off” axis), droplet diameter, as well as mass loading flow rate are investigated. It is shown that more “on-axis” injection of the droplets leads to a more straight path line, so that the droplets move less in the radial direction and are evaporated more on the central axis, enabling a better sample transfer efficiency to the sampler cone. Furthermore, there are optimum ranges of diameters and flow rates, which guarantee the proper position of evaporation along the torch, i.e. not too early, so that the sample can get lost in the torch, and not too late, which reduces the chance of becoming ionized before reaching the sampler.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000372857300003 Publication Date 2015-07-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 21 Open Access  
  Notes The authors are very grateful to H. Lindner for the many fundamental and fruitful discussions. They are also gratefully acknowledge nancial support from the Fonds voor Wetenschappelijk Onderzoek (FWO). Approved Most recent IF: 3.379  
  Call Number c:irua:133240 Serial 4024  
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Author Vermeulen, M.; Nuyts, G.; Sanyova, J.; Vila, A.; Buti, D.; Suuronen, J.-P.; Janssens, K. pdf  doi
openurl 
  Title Visualization of As(III) and As(V) distributions in degraded paint micro-samples from Baroque- and Rococo-era paintings Type A1 Journal article
  Year (up) 2016 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 31 Issue 9 Pages 1913-1921  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Orpiment and realgar, both arsenic sulfide pigments respectively used for their vivid yellow and red-orange hues, are two of many artists' pigments that appear not to be stable upon light exposure, quickly degrading to arsenic trioxide and arsenate. This often results in whitening or transparency in the painted surfaces. While conventional techniques such as microscopic Raman (mu-RS) and microscopic Fourier transform infrared (mu-FTIR) spectroscopies can allow a quick and relatively easy identification of the orpiment, realgar, artificial arsenic sulfide glass and, to some extent, arsenic oxide, the identification and visualization of distributions of the degradation products – and especially arsenate compounds – in the paint micro-samples is generally more challenging. This challenge is due to the rather unfavorable limit of detection and low spectral resolution of such conventional spectroscopic techniques. This restricts the conclusions that can be drawn regarding the conservation state of valuable works of art. In this paper, we present how synchrotron radiation (SR) based techniques can overcome this challenge while working on painting cross-sections taken from a 17th-century painting by the Flemish artist Daniel Seghers (oil on canvas, Statens Museum for Kunst, Denmark) and an 18th-century French Chinoiserie (private collection, France). SR micro-X-ray fluorescence (m-XRF) mapping analysis performed on a visually degraded orpiment-containing paint stratigraphy reveals that arsenic is distributed throughout the entire cross-section, while X-ray absorption near edge structure (mu-XANES) demonstrated that the arsenic is present in both arsenite (As-III) and arsenate (As-V) forms. The latter compound(s), despite being barely identifiable by means of FTIR, were not only located at the surface of large and partially altered grains of arsenic sulfide but also spread throughout the entire paint stratigraphy. Their presence and distribution are attributed either to the complete degradation of smaller arsenic sulfide grains or to migration of the arsenates within the paint layer away from their original location of formation. The combination of mu-XRF and mu-XANES was very useful for the characterization of the advanced degradation state of the arsenic-containing pigments in paint systems; this type of information could not be obtained by means of conventional spectroscopic methods of microanalysis.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000382071200017 Publication Date 2016-08-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 20 Open Access  
  Notes ; This research is made possible with the support of the Belgian Science Policy Office (BELSPO) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (SD/RI/04A). The CATS gratefully acknowledge VILLUM FONDEN and VELUX FONDEN for infra-structural financial support as well as Anne Haack Christensen, Hannah Tempest and Johanne M. Nielsen for their help and suggestions. The European Synchrotron Radiation Facility is acknowledged for provision of synchrotron radiation facilities. ; Approved Most recent IF: 3.379  
  Call Number UA @ admin @ c:irua:135691 Serial 5907  
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Author Bogaerts, A.; Aghaei, M. pdf  url
doi  openurl
  Title Inductively coupled plasma-mass spectrometry: insights through computer modeling Type A1 Journal article
  Year (up) 2017 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 32 Issue 32 Pages 233-261  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract In this tutorial review paper, we illustrate how computer modeling can contribute to a better insight in inductively coupled plasma-mass spectrometry (ICP-MS). We start with a brief overview on previous efforts, studying the fundamentals of the ICP and ICP-MS, with main focus on previous modeling activities. Subsequently, we explain in detail the model that we developed in previous years, and we show typical calculation results, illustrating the plasma characteristics, gas flow patterns and the sample transport, evaporation and ionization. We also present the effect of various experimental parameters, such as operating conditions, geometrical aspects and sample characteristics, to illustrate how modeling can help to elucidate the optimal conditions for improved analytical performance.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000395529800002 Publication Date 2016-12-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 14 Open Access OpenAccess  
  Notes The authors are very grateful to H. Lindner for the initial model development and for the many interesting discussions. They also gratefully acknowledge nancial support from the Fonds voor Wetenschappelijk Onderzoek (FWO; Grant number 6713). The calculations were carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. Approved Most recent IF: 3.379  
  Call Number PLASMANT @ plasmant @ c:irua:140074 Serial 4416  
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Author Vermeulen, M.; Sanyova, J.; Janssens, K.; Nuyts, G.; De Meyer, S.; De Wael, K. url  doi
openurl 
  Title The darkening of copper- or lead-based pigments explained by a structural modification of natural orpiment : a spectroscopic and electrochemical study Type A1 Journal article
  Year (up) 2017 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 32 Issue 7 Pages 1331-1341  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A combined Raman and electrochemical study of natural orpiment (As2S3), an arsenic sulfide pigment, was used to assess the quick formation of oxidized species such as arsenic oxide (As2O3) upon exposing the pigment to 405 nm or 532 nm monochromatic light while simultaneously recording the Raman spectra of the exposed sample. During this process, a distortion of the main band at 355 cm−1, associated with the stretching of the AsS3/2 pyramids of natural orpiment, was observed as well as an increased intensity of the 359 cm−1 band, corresponding to covalent AsAs bonds in natural orpiment. The distortion was accompanied by an overall decrease of the global Raman signal for natural orpiment, which could be explained by a loss in the crystal structure. The same phenomena were recorded in reference natural orpiment model paint samples stored for a long time together with verdigris (Cu(OH)2·(CH3COO)2·5H2O) and minium (Pb3O4) paints, the latter two appearing darkened on their sides closest to the orpiment sample as well as in several historical samples containing natural orpiment mixed with various blue pigments. By SEM-EDX and XRPD analysis, respectively on loose material and cast thin-sections of model paint samples, the darkening was identified as dark sulfide species such as chalcocite (Cu2S) and galena (PbS), suggesting the release of volatile sulfide or related species by the natural orpiment paint. XANES analyses of paint samples presenting AsAs bond increase indicated the presence of sulfur species most likely identified as organosulfur compounds formed upon the AsAs bond formation and explained the darkening of the Cu- and Pb-based pigments. To the best of our knowledge, this article reports for the first time the light-induced formation of AsAs bonds in natural orpiment used as an artists' pigment and objectively demonstrates the incompatibility between orpiment and (arsenic) sulfide-sensitive pigments.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000404998500007 Publication Date 2017-05-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 10 Open Access  
  Notes ; This research is made possible with the support of the Belgian Science Policy Office (BELSPO, Brussels) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (SD/RI/04A). We gratefully acknowledge Julie Arslanoglu (Conservation and Scientific Research Department at the Metropolitan Museum of Art, New York, USA) for providing us the orpiment, verdigris and minium mock-up samples. We gratefully acknowledge the Paul Scherrer Institut, Villigen, Switzerland and the German Electron Synchrotron (DESY) for provision of synchrotron radiation beamtimes at respectively beamlines of the SLS and Petra III. ; Approved Most recent IF: 3.379  
  Call Number UA @ admin @ c:irua:144384 Serial 5564  
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Author Cotte, M.; Pouyet, E.; Salome, M.; Rivard, C.; De Nolf, W.; Castillo-Michel, H.; Fabris, T.; Monico, L.; Janssens, K.; Wang, T.; Sciau, P.; Verger, L.; Cormier, L.; Dargaud, O.; Brun, E.; Bugnazet, D.; Fayard, B.; Hesse, B.; del Real, A.E.P.; Veronesi, G.; Langlois, J.; Balcar, N.; Vandenberghe, Y.; Sole, V.A.; Kieffer, J.; Barrett, R.; Cohen, C.; Cornu, C.; Baker, R.; Gagliardini, E.; Papillon, E.; Susini, J. doi  openurl
  Title The ID21 X-ray and infrared microscopy beamline at the ESRF: status and recent applications to artistic materials Type A1 Journal article
  Year (up) 2017 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 32 Issue 3 Pages 477-493  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The ID21 beamline (European Synchrotron Radiation facility, France) is a multi micro-analytical platform combining X-ray and infrared micro-probes, for characterization of elements, species, molecular groups and crystalline structures in complex materials. Applications are mainly in the fields of cultural heritage, life science, environmental and earth sciences, materials sciences. Here, we first present the status of instruments: (i) the scanning micro-spectroscopy end-station, operating from 2.0 to 9.2 keV, under vacuum and offering cryo conditions, for the acquisition of 2D micro X-ray fluorescence (mu XRF) maps, single point micro X-ray Absorption Near Edge Structure (mu XANES) spectra and speciation maps with sub-micrometric resolution; (ii) the XANES full-field end-station, operating in the same vacuum and energy conditions, for the acquisition of hyper-spectral radiographs of thin concentrated samples, resulting in speciation maps with micrometric resolution and millimetric field of view; (iii) the scanning micro-X-ray diffraction (mu XRD)/mu XRF end-station, operating at 8.5 keV, in air, for the acquisition of 2D crystalline phase maps, with micrometric resolution; and (iv) the scanning infrared microscope, operating in the mid-infrared range for the acquisition of molecular maps and some structural maps with micrometric resolution. Recent hardware and software developments are presented, as well as new protocols for improved sample preparation of thin sections. Secondly, a review of recent applications for the study of cultural heritage is presented, illustrated by various examples: determination of the origin of the color in blue Chinese porcelains and in brown Sevres porcelains; detection of lead in ink on Herculaneum papyri; identification and degradation of modeling materials used by Auguste Rodin and of chrome yellow pigments used by Vincent van Gogh. Cryo capabilities are illustrated by the analysis of plants exposed to chromate solutions. These examples show the variety of materials analyzed, of questions tackled, and particularly the multiple advantages of the ID21 analytical platform for the analysis of ancient and artistic materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000396286900002 Publication Date 2016-12-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 39 Open Access  
  Notes ; ; Approved Most recent IF: 3.379  
  Call Number UA @ admin @ c:irua:142493 Serial 5874  
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Author Verlinden, B.; Van Hoecke, K.; Aerts, A.; Daems, N.; Dobney, A.; Janssens, K.; Cardinaels, T. doi  openurl
  Title Quantification of boron in cells for evaluation of drug agents used in boron neutron capture therapy Type A1 Journal article
  Year (up) 2021 Publication Journal Of Analytical Atomic Spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 36 Issue 3 Pages 598-606  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Boron neutron capture therapy (BNCT) is an extensively studied radiotherapeutic strategy for cancer treatment. BNCT is based on irradiation of malignant tumour cells with neutrons after uptake of a B-10 containing molecule. Alpha particles, locally produced by neutron irradiation kill the cancer cells. Important for ongoing research regarding cellular uptake and cytotoxicity of a large variety of B-10 containing molecules is the accurate determination of boron concentrations in cell cultures. In this work, the sample preparation for quantitative inductively coupled plasma mass spectrometry (ICP-MS) analysis on cell cultures was optimized. By making use of acid digestion combined with UV digestion, low detection limits (0.4 mu g L-1) and full recoveries of boron could be achieved while measurements were free of spectral and non-spectral interferences. Finally, cell-associated boron in the form of 4-borono-l-phenylalanine (l-BPA) in vascular endothelial cell cultures could be determined with ICP-MS as (1.26 +/- 0.10) x 10(9) boron atoms per cell. The developed method can prove its importance for further BNCT research and elemental analysis of cell cultures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000629283400009 Publication Date 2021-01-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.379  
  Call Number UA @ admin @ c:irua:177656 Serial 8435  
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Author Monico, L.; Prati, S.; Sciutto, G.; Catelli, E.; Romani, A.; Balbas, D.Q.; Li, Z.; De Meyer, S.; Nuyts, G.; Janssens, K.; Cotte, M.; Garrevoet, J.; Falkenberg, G.; Tardillo Suarez, V.I.; Tucoulou, R.; Mazzeo, R. url  doi
openurl 
  Title Development of a multi-method analytical approach based on the combination of synchrotron radiation X-ray micro-analytical techniques and vibrational micro-spectroscopy methods to unveil the causes and mechanism of darkening of “fake-gilded” decorations in a Cimabue painting Type A1 Journal article
  Year (up) 2022 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 37 Issue 1 Pages 114-129  
  Keywords A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS)  
  Abstract Redox processes activated by environmental factors have been identified as the main cause of the chromatic alterations of a number of artists' pigments, including the yellow pigment orpiment (As2S3). Although a general comprehension of the mechanisms has been provided through characterization of degradation compounds of As2S3, experimental evidences to prove how other paint components and how different environmental agents influence the formation pathways of specific secondary compounds are still lacking. Thus, it becomes fundamental to develop a methodological strategy which enable achieving a discrimination among the causes affecting the chemical stability of more heterogenous As2S3-based paints and defining the mechanism through which the alteration establishes and evolves, with the ultimate goal of optimizing the preventive conservation measures of unique masterpieces. In this paper, we propose a comprehensive multi-material and multi-method approach based on the combination of synchrotron radiation X-ray micro-analytical techniques (i.e., X-ray diffraction, X-ray fluorescence and X-ray absorption near edge structure spectroscopy at S K-/Ag L-3-/As K-edges) and vibrational micro-spectroscopy methods to unveil the causes and mechanism of darkening of “fake-gilded” decorations in tempera paintings, originally consisting of an unusual mixture of As2S3 and metallic silver (Ag-0). Such degradation process is a not yet understood phenomenon threatening a series of Old Master paintings, including those by the Italian painters Cimabue and Pietro Lorenzetti. The high specificity, sensitivity and lateral resolution of the employed analytical methods allowed providing first-time evidence for the presence of black acanthite (alpha-Ag2S), mimetite [Pb-5(AsO4)(3)Cl] and syngenite [K2Ca(SO4)(2)center dot H2O] as degradation products of the “fake-gilded” decorations in the Maesta by Cimabue (Church of Santa Maria dei Servi, Bologna, Italy). Furthermore, the study of the painting combined with that of tempera paint mock-ups permitted to explore and define the environmental agents and internal factors causing the darkening, by proving that: (i) Ag-0 and moisture are key-factors for triggering the transformation of As2S3 to alpha-Ag2S and As-oxides; (ii) S2--ions arising from the degradation of As2S3 are the main responsible for the formation of alpha-Ag2S; (iii) light exposure strengthens the tendency of the paint components towards alteration. Based on our findings, we finally propose a degradation mechanism of As2S3/Ag-0-based tempera paints.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000722353400001 Publication Date 2021-11-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.4 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.4  
  Call Number UA @ admin @ c:irua:184871 Serial 7142  
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