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Author Trentelman, K.; Janssens, K.; van der Snickt, G.; Szafran, Y.; Woollett, A.T.; Dik, J.
Title Rembrandt's An Old Man in Military Costume: the underlying image re-examined Type A1 Journal article
Year 2015 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
Volume 121 Issue 3 Pages 801-811
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The painting An Old Man in Military Costume in the J. Paul Getty Museum, by Rembrandt Harmensz van Rijn, was studied using two complementary, element-specific imaging techniques-neutron activation autoradiography (NAAR) and macro-X-ray fluorescence (MA-XRF) mapping-to reveal the second, hidden painting. NAAR provided a strong image of the face and cloak of the underlying figure, along with an indication of the chemical composition. The single-element distribution maps produced by MA-XRF mapping provided additional details into the shape of the underlying image and the composition of the pigments used. The underlying figure's face is richer in mercury, indicative of the pigment vermilion, than the face of the figure on the surface. Likewise, the cloak of the underlying figure is richer in copper than the surface figure though the identity of the copper-containing pigment cannot be determined from these data. The use of iron earth pigments, specifically Si-rich umbers, is indicated through the complementary information provided by the NAAR and MA-XRF maps. These data are used to create a false color digital reconstruction, yielding the most detailed representation of the underlying painting to date.
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Publisher Place of Publication Editor
Language Wos 000364914100003 Publication Date 2015-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.455 Times cited (down) 22 Open Access
Notes ; The authors gratefully acknowledge the assistance of all those who aided in the examination of this painting over the decades, that has culminated in the work presented here. Particular thanks go to Mark Leonard (former head of Paintings Conservation at the J. Paul Getty Museum) and Henry Prask (NIST) for carrying out the NAAR analysis; John Twilley (former GCI Scientist) for early investigations; Andrea Sartorius (former JPGM Paintings intern) for creating a mock-up painting used in earlier phases of this work; Peter Reishig (former GCI intern) for compiling the NAAR data; Catherine Patterson, Lynn Lee, and David Carson (GCI Science) and Gene Karraker (JPGM Paintings Conservation) for helping with the setup and operation of the M6 Jetstream; and Giacomo Chiari (former head of GCI Science) for performing the XRD analysis. Koen Janssens and Geert van der Snickt acknowledge the Fund Inbev-Baillet Latour for financial support. Joris Dik acknowledges the help of the Netherlands Organization for Scientific Research (NWO) in the form of a VIDI grant in the Innovational Research Incentive Scheme. ; Approved Most recent IF: 1.455; 2015 IF: 1.704
Call Number UA @ admin @ c:irua:130289 Serial 5812
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Author Kempenaers, L.; Janssens, K.; Vincze, L.; Vekemans, B.; Somogyi, A.; Drakopoulos, M.; Simionovici, A.S.; Adams, F.
Title A Monte Carlo model for studying the microheterogeneity of trace elements in reference materials by means of synchrotron microscopic X-ray fluorescence Type A1 Journal article
Year 2002 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 74 Issue 19 Pages 5017-5026
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000178418100031 Publication Date 2002-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited (down) 21 Open Access
Notes Approved Most recent IF: 6.32; 2002 IF: 5.094
Call Number UA @ admin @ c:irua:39871 Serial 5734
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Author Denecke, M.A.; Brendebach, B.; de Nolf, W.; Falkenberg, G.; Janssens, K.; Simon, R.
Title Spatially resolved micro-X-ray fluorescence and micro-X-ray absorption fine structure study of a fractured granite bore core following a radiotracer experiment Type A1 Journal article
Year 2009 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal Spectrochim Acta B
Volume 64 Issue 8 Pages 791-795
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Spatially resolved X-ray absorption and fluorescence investigation with a micrometer-scale resolution on actinide-containing samples provide information necessary for safety assessment of nuclear waste disposal. In this paper one example of such an experiment is presented. This example entails neptunium speciation in a fractured granite bore core from the Swedish Äspö Hard Rock Laboratory following a radiotracer experiment using µ-XAFS and µ-XRF. In order to probe micro-volumes below the surface in the granite samples and thereby avoid potential changes in the Np speciation during cutting of the bore core, a confocal irradiationdetection geometry is employed. µ-XAFS results for a selected granite bore core cross section with ~ 3 nmol Np/g reveal that Np, originally introduced as Np(V) in the tracer cocktail, is present in the granite in its reduced Np(IV) form. The Np(IV) is often present as particles, tens of µm in size. Elemental distribution maps show the tracer Np to be located in fissures and permeable channels not larger than 100 µm. The Np distribution appears often correlated with Zn also present in some fissures. We observe small granite fissures containing Fe (presumably Fe(II)), where we do not detect any Np. It is feasible that inflowing Np(V) has a shorter residence time in large fractures, while in the smaller fissures migration is slower, leading to longer residence times, i.e., reaction times, where it is reduced to less soluble Np(IV) and becomes thereby immobilized.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000269995300013 Publication Date 2009-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0584-8547; 0038-6987 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.241 Times cited (down) 21 Open Access
Notes Approved Most recent IF: 3.241; 2009 IF: 2.719
Call Number UA @ admin @ c:irua:79740 Serial 5837
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Author Cagno, S.; Badano, M.B.; Mathis, F.; Strivay, D.; Janssens, K.
Title Study of medieval glass fragments from Savona (Italy) and their relation with the glass produced in Altare Type A1 Journal article
Year 2012 Publication Journal of archaeological science Abbreviated Journal J Archaeol Sci
Volume 39 Issue 7 Pages 2191-2197
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Altare was in the medieval and post-medieval period an important glassmaking center in the Liguria region in Northern Italy. The first historical evidence of glassmaking in Altare is dated to the twelfth century. In spite of that, due to the continuity of glassmaking up to the present time and the contemporaneous intensive urbanization of the territory, no medieval glass from Altare or its immediate vicinity has been analyzed up to now. In this work, glass from archaeological excavations in the center of Savona, city with close ties with the glassmaking center, was studied. Glass fragments, dated from the tenth to the sixteenth century were selected from the collections of the Archaeological Museum in Savona and non-destructively analyzed with quantitative PIXE-PIGE. The resulting compositions, compared with known glass productions of the same time and evaluated on the basis of historical documents, offer an interesting panorama on the variety of glass circulation in Liguria. (C) 2012 Elsevier Ltd. All rights reserved.
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Language Wos 000305849400027 Publication Date 2012-03-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0305-4403 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.602 Times cited (down) 21 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. The authors gratefully acknowledge Prof. Carlo Varaldo for allowing the study of the glass preserved in the Archaeological Museum of Savona. ; Approved Most recent IF: 2.602; 2012 IF: 1.889
Call Number UA @ admin @ c:irua:100332 Serial 5849
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Author Centeno, S.A.; Hale, C.; Caro, F.; Cesaratto, A.; Shibayama, N.; Delaney, J.; Dooley, K.; van der Snickt, G.; Janssens, K.; Stein, S.A.
Title Van Gogh's Irises and Roses : the contribution of chemical analyses and imaging to the assessment of color changes in the red lake pigments Type A1 Journal article
Year 2017 Publication Heritage science Abbreviated Journal
Volume 5 Issue Pages 18
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Vincent van Gogh's still lifes Irises and Roses were investigated to shed light onto the degree to which the paintings had changed, both individually and in relation to each other since they were painted, particularly in regard to the fading of the red lakes. Non-invasive techniques, including macroscopic X-ray fluorescence mapping, reflectance imaging spectroscopy, and X-radiography, were combined with microanalytical techniques in a select number of samples. The in-depth microchemical analysis was necessary to overcome the complications that arise when evaluating by non-invasive methods alone the compositions of passages with complex layering and mixing of paints. The results obtained by these two approaches were complemented by color measurements performed on paint cross-sections and on protected edges, and with historical information provided by the artist's own descriptions, early reviews and reproductions, and the data was used to carry out digital color simulations that provided, to a certain extent, a visualization of how the paintings may have originally appeared.
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Publisher Place of Publication Editor
Language Wos 000401365400001 Publication Date 2017-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited (down) 21 Open Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:143748 Serial 5903
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Author Ceglia, A.; Nuyts, G.; Meulebroeck, W.; Cagno, S.; Silvestri, A.; Zoleo, A.; Nys, K.; Janssens, K.; Thienpont, H.; Terryn, H.
Title Iron speciation in soda-lime-silica glass: a comparison of XANES and UV-vis-NIR spectroscopy Type A1 Journal article
Year 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom
Volume 30 Issue 7 Pages 1552-1561
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Scientific analyses of ancient glasses have been carried out for many years using elemental chemical analysis. However, it is known that the control of the redox conditions in the glass melt has a strong implication on the final hue of glass because it affects Fe2+/SFe. Therefore an increasing number of studies on the redox conditions have been published in recent years by means of synchrotron based Xray absorption spectroscopy. This is a technique which is not easily accessible and requires dedicated facilities. In this paper we describe an alternative approach by means of optical absorption spectroscopy. We synthesised 10 soda-lime-silica glasses with known redox conditions and iron concentration to calibrate the absorption at 1100 nm as a function of Fe2+ concentration. The linear extinction coefficient was also determined. These glasses were also studied by means of X-ray Absorption Near Edge Structure (XANES) spectroscopy. Electron paramagnetic resonance spectroscopy was additionally used as an ancillary method to verify the quality of our data. Furthermore 28 samples from real archaeological samples were analysed by XANES and optical spectroscopy as a case study. The Fe2+/SFe values obtained were compared and demonstrated that the two techniques were in good agreement with each other. Optical spectroscopy can be applied in situ with moderate sample preparation to determine the concentration of Fe2+. To investigate the redox conditions, especially as a first screening approach, this methodology is an important tool to take into consideration before applying more sophisticated techniques such as XANES, which is more elaborate and requires high-tech resources.
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Language Wos 000356971900009 Publication Date 2015-04-15
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 (down) 20 Open Access
Notes ; The research leading to these results has received funding from the European Union Seventh Framework Programme FP7/2007-2013 under grant agreement no. 265010. For more information please visit the NARNIA website: http:// narnia-itn.eu/. This work was partly supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/ F50. We are grateful to the ESRF for granting beamtime and Dipanjan Banerjee for his help at the beamline. We are thankful to the R&D department of AGC Glass Europe, in particular Dr Benoit Cherdon, Dr Dominique Michiels and Ms Dominique Delleuze, for preparing glass for us and providing us the chemical information. A special thanks to M. Fialin for the help with EPMA measurements in CAMPARIS. We want to express our gratitude to F. Farges and A. Berry for sharing their XANES spectra with us. Thanks to Anne Isabelle for reading this paper and giving comments. Finally we are grateful to two anonymous reviewers who contributed to improve this paper. ; Approved Most recent IF: 3.379; 2015 IF: 3.466
Call Number UA @ admin @ c:irua:127060 Serial 5679
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Author Padilla, R.; Schalm, O.; Janssens, K.; Arrazcaeta, R.; van Espen, P.
Title Microanalytical characterization of surface decoration in Majolica pottery Type A1 Journal article
Year 2005 Publication Analytica chimica acta Abbreviated Journal Anal Chim Acta
Volume 535 Issue 1-2 Pages 201-211
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000228194200025 Publication Date 2005-01-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2670 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.95 Times cited (down) 20 Open Access
Notes Approved Most recent IF: 4.95; 2005 IF: 2.760
Call Number UA @ admin @ c:irua:52143 Serial 5722
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Author Vermeulen, M.; Nuyts, G.; Sanyova, J.; Vila, A.; Buti, D.; Suuronen, J.-P.; Janssens, K.
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 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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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 (down) 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 Anaf, W.; Janssens, K.; De Wael, K.
Title Formation of metallic mercury during photodegradation/photodarkening of \alpha-HgS : electrochemical evidence Type A1 Journal article
Year 2013 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 52 Issue 48 Pages 12568-12571
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Das rote Pigment α-HgS neigt in Gegenwart von Licht und Chloridionen zur Schwärzung. Als Grund für die Zersetzung und Entfärbung werden die Bildung von (schwarzem) β-HgS oder Quecksilbermetall vermutet, doch diese Substanzen wurden noch nicht auf natürlich oder künstlich zersetzter HgS-Farbe nachgewiesen. Elektrochemische Experimente belegen nun die Bildung von Quecksilbermetall in Gegenwart von Licht und Chloridionen.
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Language Wos 000327582900015 Publication Date 2013-10-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited (down) 19 Open Access
Notes ; The authors acknowledge L. Klaassen for valuable discussions and providing samples. We acknowledge financial support from the SDD programme (S2-ART project) of the Belgian Federal Goverment. ; Approved Most recent IF: 11.994; 2013 IF: 11.336
Call Number UA @ admin @ c:irua:111265 Serial 5626
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Author Cagno, S.; Cosyns, P.; Izmer, A.; Vanhaecke, F.; Nys, K.; Janssens, K.
Title Deeply colored and black-appearing Roman glass : a continued research Type A1 Journal article
Year 2014 Publication Journal of archaeological science Abbreviated Journal J Archaeol Sci
Volume 42 Issue Pages 128-139
Keywords A1 Journal article; Philosophy; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In the context of archaeological and historical assessment of Roman black-appearing glass, the chemical and physical characterization of a large collection of samples originating from various areas of the Roman Empire has been gathered over the past years to (i) verify whether a minor segment of the overall Roman glass production can help in determining possible diachronic changes in Roman imperial glass production (1st century AD – 5th century AD) and (ii) reveal regional compositional differences. In this paper, the latest results on the chemical composition of an additional 44 black-appearing Roman glass samples are presented, together with general conclusions based upon the entire compositional dataset of over 400 analyzed black glass samples. The results show that the Roman black glass is obtained through several glass compositions with a specific chronological, geographical and typological distribution. (C) 2013 Elsevier Ltd. All rights reserved.
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Publisher Place of Publication Editor
Language Wos 000332133100011 Publication Date 2013-11-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0305-4403 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.602 Times cited (down) 18 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16) and the Hercules fund, Brussels (grant A11/ 0387). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium), FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09, and VUB project OZR-BOF 1247. This work was partly supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/F50. ; Approved Most recent IF: 2.602; 2014 IF: 2.196
Call Number UA @ admin @ c:irua:115865 Serial 5567
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Author Anaf, W.; Trashin, S.; Schalm, O.; van Dorp, D.; Janssens, K.; De Wael, K.
Title Electrochemical photodegradation study of semiconductor pigments : influence of environmental parameters Type A1 Journal article
Year 2014 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 86 Issue 19 Pages 9742-9748
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Chemical transformations in paintings often induce discolorations, disturbing the appearance of the image. For an appropriate conservation of such valuable and irreplaceable heritage objects, it is important to have a good know-how on the degradation processes of the (historical) materials: which pigments have been discolored, what are the responsible processes, and which (environmental) conditions have the highest impact on the pigment degradation and should be mitigated. Pigment degradation is already widely studied, either by analyzing historical samples or by accelerated weathering experiments on dummies. However, in historic samples several processes may have taken place, increasing the complexity of the current state, while aging experiments are time-consuming due to the often extended aging period. An alternative method is proposed for a fast monitoring of degradation processes of semiconductor pigments, using an electrochemical setup mimicking the real environment and allowing the identification of harmful environmental parameters for each pigment. Examples are given for the pigments cadmium yellow (CdS) and vermilion (α-HgS).
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Publisher Place of Publication Editor
Language Wos 000343017100058 Publication Date 2014-08-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited (down) 18 Open Access
Notes ; ; Approved Most recent IF: 6.32; 2014 IF: 5.636
Call Number UA @ admin @ c:irua:118834 Serial 5593
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Author Meulebroeck, W.; Cosyns, P.; Baert, K.; Wouters, H.; Cagno, S.; Janssens, K.; Terryn, H.; Nys, K.; Thienpont, H.
Title Optical spectroscopy as a rapid and low-cost tool for the first-line analysis of glass artefacts : a step-by-step plan for Roman green glass Type A1 Journal article
Year 2011 Publication Journal of archaeological science Abbreviated Journal J Archaeol Sci
Volume 38 Issue 9 Pages 2387-2398
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Archaeometric research on glass artefacts is continuously evolving and is converging towards a multidisciplinary research domain where different types of techniques are applied depending on the questions asked and the circumstances involved. The technique described in this work is optical spectroscopy. The benefit of this technique being the possibility of building up a knowledge database for a large amount of material in a relatively short period of time and with a relatively limited budget. This is of particular interest for the investigation of extensive and/or unexplored glass collections where a first-line analysis of artefacts could facilitate the selection of material needing further and more detailed examination. This publication explores the extent to which optical spectroscopy can be used for a first-line analysis of green coloured glass artefacts from the Roman period. It is shown that the colour coordinates calculated from the measured transmission spectrum could reveal information about the fragment under study. In particular it is shown that 1) based on the position of the calculated colour values on the colour diagram (CIE1931) one could easily know whether the artefact was coloured using only iron or if copper oxides were also present. In the case of the artefact owing its colour solely to the presence of iron, the distance between the measured colour values and the colour diagrams white point can roughly indicate the iron concentration of the sample; 2) artefacts that were fabricated under similar furnace conditions can also be identified on the colour diagram; 3) samples with identical compositions and fabrication conditions but with different sample thickness, gave rise to a variation in the colour coordinates, thus allowing optical spectroscopy to help identify fragments which might belong to the same object.
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Publisher Place of Publication Editor
Language Wos 000293551200037 Publication Date 2011-05-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0305-4403 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.602 Times cited (down) 18 Open Access
Notes ; The authors would like to express their gratitude to the Vrije Universiteit Brussel for funding this research in the framework of HOA15, a “Horizontal Research Action” which encourages collaboration between research groups from different departments within the same University having expertise in specific research disciplines and also to the OZR-project 1247 BOF. The authors are also very grateful to the following persons for having permitted the study of their material: Rica Annaert and Sofie Vanhoutte of the “Vlaams lnstituut voor Onroerend Erfgoed (VIOE): Grobbendonk, Matagne-la-Petite, Oudenburg; Jean-Louis Antoine of the Musee Archeologique Namur: Nismes; Tom Debruyne of the ”Erfgoedcel“ Tienen: Tienen: Marc Rogge and Kurt Braeckman of the ”Provinciaal Archeologisch Museum (PAM)": Kruishoutem, Velzeke; Walter Sevenants: Rumst and Anne de Pyre-Gysel from the Musee Romain d'Avenches: Avenches. ; Approved Most recent IF: 2.602; 2011 IF: 1.914
Call Number UA @ admin @ c:irua:92389 Serial 5756
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Author Alvarez-Martin, A.; Trashin, S.; Cuykx, M.; Covaci, A.; De Wael, K.; Janssens, K.
Title Photodegradation mechanisms and kinetics of Eosin-Y in oxic and anoxic conditions Type A1 Journal article
Year 2017 Publication Dyes and pigments Abbreviated Journal Dyes Pigments
Volume 145 Issue Pages 376-384
Keywords A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract Lakes based on Eosin-Y are extensively used by 19th century artists. Unfortunately, the identification of these pigments in paintings is a difficult task because Eosin-Y degrades very fast under the influence of light. The characterization of the (photo)degradation products of Eosin-Y can be very useful for the identification of these pigments in historic works of art and related cultural heritage artifacts. Furthermore, knowledge on how different factors influence the discoloration process (e.g. different types of irradiation sources and presence/absence of oxygen) is a valuable tool for preventive conservation. To this aim we performed a study on the photodegradation of Eosin-Y in solution under different illumination and in both oxic and anoxic conditions. The photodegradation of Eosin-Y was monitored by UV-VIS spectrophotometry, LC-QTOFMS and electrochemistry techniques. Results indicated higher degradation rates, by a factor of 20 or higher, under illumination with wavelengths near to the main absorbance band of the red pigment. Two different degradation pathways are observed under the conditions studied. LC-QTOFMS and electrochemistry suggested that in the presence of oxygen the degradation mechanism is an oxidative process where the breakdown of the structure causes the total discoloration. Meanwhile under anoxic conditions, a debromination process takes place while the chromophore, and consequently the color of the molecule in solution, remains essentially intact.
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Language Wos 000405972900046 Publication Date 2017-06-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0143-7208 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.473 Times cited (down) 18 Open Access
Notes ; ; Approved Most recent IF: 3.473
Call Number UA @ admin @ c:irua:144385 Serial 5770
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Author Janssens, K.; van der Snickt, G.; Alfeld, M.; Noble, P.; van Loon, A.; Delaney, J.; Conover, D.; Zeibel, J.; Dik, J.
Title Rembrandt's 'Saul and David' (c. 1652) : use of multiple types of smalt evidenced by means of non-destructive imaging Type A1 Journal article
Year 2016 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 126 Issue Pages 515-523
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The painting Saul and David, considered to date from c. 1652 and previously attributed to Rembrandt van Rijn and/or his studio, is a complex work of art that has been recently subjected to intensive investigation and conservation treatment. The goal of the research was to give insight into the painting's physical construction and condition in preparation for conservation treatment. It was also anticipated that analysis would shed light on authenticity questions and Rembrandt's role in the creation of the painting. The painting depicts the Old Testament figures of King Saul and David. At left is Saul, seated, holding a spear and wiping a tear from his eye with a curtain. David kneels before him at the right playing his harp. In the past, the large sections with the life-size figures were cut apart and later reassembled. A third piece of canvas was added to replace a missing piece of canvas above the head of David. As part of the investigation into the authenticity of the curtain area, a number of paint micro samples were examined with LM and SEM-EDX. Given that the earth, smalt and lake pigments used in the painting could not be imaged with traditional imaging techniques, the entire painting was also examined with state of the art non-destructive imaging techniques. Special attention was devoted to the presence of cobalt-containing materials, specifically the blue glass pigment smalt considered characteristic for the late Rembrandt. A combination of quantitative electron microprobe analysis and macroscopic X-ray fluorescence scanning revealed that three types of cobalt-containing materials are present in the painting. The first type is a cobalt drier that was found in the overpaint used to cover up the canvas inset and the joins that were added in the 19th century. The other two Co-containing materials are part of the original paint used by Rembrandt and comprise two varieties of smalt, a K-rich glass pigment that derives its gray-blue color by doping with Co-ions. Smalt paint with a higher Ni content (NiO:CoO ratio of around 1:4) was used to depict the blue stripes in Saul's colorful turban, while smalt with a lower Ni content was employed (NiO:CoO ratio of around 1:5) for the broad expanses of Saul's garments. The presence of two types of smalt not only supports the recent re-attribution of the painting to Rembrandt, but also that the picture was painted in two phases. Saul's dark red garment is painted in a rough, “loose” manner and the now discolored smalt-rich layer was found to have been partially removed during a past restoration treatment/s. In contrast, the blue-green smalt in the turban is much better preserved and provides a colorful accent. While the use of different types of smalt in a Rembrandt painting has been previously identified using quantitative EDX analysis of paint cross-sections, to the best of our knowledge this is the first time such a distinction has been observed in a 17th-century painting using non-destructive imaging techniques. In addition to the XRF-based non-invasive elemental mapping, hyperspectral imaging in the visual to near-infrared (VNIR) region was also carried out. (C) 2016 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000373647500063 Publication Date 2016-01-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited (down) 18 Open Access
Notes ; This research is part of the ReVisualising late Rembrandt: Developing and Applying New Imaging Techniques research project, supported by the Science4Arts research program of the Netherlands Organisation for Scientific Research (NWO, The Hague, NL, ReVisRembrandt project) and the National Science Foundation (NSF, Washington DC, USA, award 1041827). We would like to thank colleagues of the Mauritshuis (The Hague, NL) and the Dutch Cultural Heritage Agency (RCE) in Rijswijk, NL for their support and assistance during the scanning of the Saul and David painting. The GOA project “SOLARPAINT” (University of Antwerp) and the Fund Baillet Latour (Brussels, B) are acknowledged for financial support to GvdS and KJ. We also like to acknowledge the help of Eliza Longhini and Stijn Legrand during some of the XRF scanning stages. ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:133258 Serial 5813
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Author Kukhlevsky, S.V.; Mechler, M.; Csapo, L.; Janssens, K.; Samek, O.
Title Enhanced transmission versus localization of a light pulse by a subwavelength metal slit Type A1 Journal article
Year 2004 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 70 Issue 19 Pages 195428,1-9
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000225477800152 Publication Date 2004-11-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited (down) 17 Open Access
Notes Approved Most recent IF: 3.836; 2004 IF: 3.075
Call Number UA @ admin @ c:irua:50849 Serial 5604
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Author Cagno, S.; Nuyts, G.; Bugani, S.; De Vis, K.; Schalm, O.; Caen, J.; Helfen, L.; Cotte, M.; Reischig, P.; Janssens, K.
Title Evaluation of manganese-bodies removal in historical stained glass windows via SR-\mu-XANES/XRF and SR-\mu-CT Type A1 Journal article
Year 2011 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom
Volume 26 Issue 12 Pages 2442-2451
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The speed and effectiveness of a conservation treatment used for stained glass windows have been investigated. Dark-coloured Mn-rich stains can be found in the alteration layer of ancient glass artefacts and cause the surface to turn brown/black: this phenomenon is known as Mn-browning or Mn-staining. While in glass manganese is present in the +II or +III oxidation states, in the Mn-rich bodies, manganese is in a higher oxidation state (+IV). In restoration practice, mildly reducing solutions are employed to eliminate the dark colour and restore the clear appearance of the glass. In this paper the effectiveness and side effects of the use of hydroxylamine hydrochloride for this purpose are assessed. Archaeological fragments of stained glass windows, dated to the 14th century and originating from Sidney Sussex College, Cambridge (UK), were examined by means of synchrotron radiation (SR) based microscopic X-ray Absorption Near-Edge Spectroscopy (μ-XANES) and microscopic X-Ray Fluorescence (μ-XRF) and with high resolution computed absorption tomography (μ-CT) before, during and after the treatment. The monitoring of the glass fragments during the treatment allows us to better understand the manner in which the process unfolds and its kinetics. The results obtained reveal that the hydroxylamine hydrochloride treatment is effective, but also that it has a number of unwanted side effects. These findings are useful for optimizing the time and other modalities of the Mn-reducing treatment as well as minimizing its unwanted results.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000297030400009 Publication Date 2011-10-11
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 (down) 17 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. Special thanks to Ms Leonie Seliger, head of the stained-glass conservation studio (The Cathedral Studios-The Chapter of Canterbury Cathedral) for the supply of the archaeological samples. The authors gratefully acknowledge ESRF for granting beamtime (proposal EC-602). ; Approved Most recent IF: 3.379; 2011 IF: 3.220
Call Number UA @ admin @ c:irua:93848 Serial 5613
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Author Vermeulen, M.; Sanyova, J.; Janssens, K.
Title Identification of artificial orpiment in the interior decorations of the Japanese tower in Laeken, Brussels, Belgium Type A1 Journal article
Year 2015 Publication Heritage science Abbreviated Journal
Volume 3 Issue Pages Unsp 9
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this paper, we used a multi-technique approach in order to identify the arsenic sulfide pigment used in the decorative panels of the Japanese tower in Laeken, Belgium. Our attention was drawn to this particular pigment because of its relatively good conservation state, despite its known tendency to fade over time when exposed to light. The pigment was used with different painting techniques, bound with oil and urushi in the lacquers and with an aqueous binder in the mat relief panels. In the latter case it is always applied as an underlayer mixed with ultramarine blue. This quite unusual pigment mixture also shows a good state of preservation. In this study, the orpiment used for the Japanese tower has been identified as an amorphous arsenic sulfide glass (AsxSx) with the aid of light microscopy, PLM, SEM-EDX and Raman microscopy. The pigment features different degrees of As4S4 monomer units in its structure, also known as realgar-like nano-phases. This most likely indicates different synthesis processes as the formation of these As4S4 monomers is dependent of the quenching temperature (Tq) to which the artificial pigment is exposed during the preparation phase.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000356920400001 Publication Date 2015-02-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited (down) 17 Open Access
Notes ; We cordially thank Gunter Grundmann for his precious advice regarding PLM and arsenic sulfide glass. 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). ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:124904 Serial 5649
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Author Terzano, R.; Spagnuolo, M.; Medici, L.; Dorriné, W.; Janssens, K.; Ruggiero, P.
Title Microscopic single particle characterization of zeolites synthesized in a soil polluted by copper or cadmium and treated with coal fly ash Type A1 Journal article
Year 2007 Publication Applied clay science Abbreviated Journal Appl Clay Sci
Volume 35 Issue 1-2 Pages 128-138
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000243825800016 Publication Date 2006-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-1317 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.101 Times cited (down) 17 Open Access
Notes Approved Most recent IF: 3.101; 2007 IF: 1.861
Call Number UA @ admin @ c:irua:62999 Serial 5723
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Author Monico, L.; Janssens, K.; Cotte, M.; Romani, A.; Sorace, L.; Grazia, C.; Brunetti, B.G.; Miliani, C.
Title Synchrotron-based X-ray spectromicroscopy and electron paramagnetic resonance spectroscopy to investigate the redox properties of lead chromate pigments under the effect of visible light Type A1 Journal article
Year 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom
Volume 30 Issue 7 Pages 1500-1510
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Light-induced redox processes have been established as the cause of the chromatic alterations of a number of artists' pigments used from the 15th to the 20th century. Despite the fact that a general comprehension of the mechanisms has been provided through the characterization of photo-degraded compounds, both exhaustive information on the wavelength-dependence of the alteration process of the pigments and experimental evidence in how visible light may influence the formation pathways of specific secondary compounds are still lacking. Establishing an analytical protocol for the study of wavelength-dependence of pigments on photo-redox pathways is relevant for the safe illumination of paintings, especially in view of the possible use of spectrally tunable light sources such as white light emitting diodes (WLEDs). In this work, we propose an integrated approach based on a combination of diffuse reflectance UV-visible, synchrotron radiation (SR)-based micro X-ray fluorescence (m-XRF)/X-ray absorption near edge structure (m-XANES) and electron paramagnetic resonance (EPR) spectroscopies to study the photo-redox process of Cr(VI) -> Cr(III) for lead chromate yellows (PbCr1-xSxO4, 0 <= x <= 0.8) under exposure to different monochromatic light. In view of the thin (3-5 mm) alteration layer that is formed at the paint surface after light exposure, SR-based Cr K-edge mu-XANES/mu-XRF analysis was employed to obtain information on the abundance, nature and distribution of the alteration of Cr(III)-compounds at the micrometricscale level. On the other hand, EPR spectroscopy was used as a complementary tool to the SR-based X-ray methods due to its sensitivity for revealing species containing one or more unpaired electrons and for distinguishing different coordination geometries of paramagnetic centers, such as Cr(V)-species. Semi-quantitative indications about the darkening of the paint surface were obtained by UV-Vis spectroscopy. An abundance of reduced Cr down to around 50% was detected at the aged surface of chrome yellow paints. The reduction process was favored not only by wavelengths shorter than 460 nm (i.e., where the pigment shows its maximum absorption) but also by light in the 490-530 nm range. The first evidence of the presence of Cr(V)-intermediates in the Cr(VI) -> Cr(III) reduction reaction allowed the risks of inducing photo-degradation of the 490-530 nm wavelength range to be explained.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000356971900004 Publication Date 2015-04-15
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 (down) 17 Open Access
Notes ; This research was supported by the Italian projects PRIN-(SICH) and PON- (ITACHA) and by Belgian Science Policy project S2-ART (BELSPO S4DA), the GOA “SOLARPAINT” (Research Fund Antwerp University, Belgium) and FWO (Brussels, Belgium) projects no. G.0C12.13, G.0704.08 and G.01769.09. ESRF is acknowledged for the grants received (experiments HG18 and HG26). L.S. and L.M. acknowledge the financial support of Ente-CRF and CNR-Short Term Mobility Programme 2013, respectively. ; Approved Most recent IF: 3.379; 2015 IF: 3.466
Call Number UA @ admin @ c:irua:127059 Serial 5862
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Author Lind, O.C.; de Nolf, W.; Janssens, K.; Salbu, B.
Title Micro-analytical characterisation of radioactive heterogeneities in samples from Central Asian TENORM sites Type A1 Journal article
Year 2013 Publication Journal of environmental radioactivity Abbreviated Journal J Environ Radioactiv
Volume 123 Issue Pages 63-70
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The present work focuses on the use of micro-analytical techniques to demonstrate the heterogeneous distribution of radionuclides and metals in soils collected at Former Soviet Union mining sites in Central Asia. Based on digital autoradiography, radionuclides were heterogeneously distributed in soil samples collected at the abandoned uranium mining sites Kurday, Kazakhstan, Kadji Sai, Kyrgyzstan and Taboshar, Tajikistan. Using electron microscopy interfaced with X-ray microanalysis submicron – mm-sized radioactive particles and rock fragments with U, As, Se and toxic metals on the surfaces were identified in Kurday and Kadji Sai samples. Employing scanning and tomographic (3D) synchrotron radiation based micro-X-ray fluorescence (mu-SRXRF) and synchrotron radiation based micro-X-ray diffraction (mu-SRXRD) allowed us to observe the inner structure of the particles without physical sectioning. The distribution of elements in virtual crosssections demonstrated that U and a series of toxic elements were rather heterogeneously distributed also within individual radioactive TENORM particles. Compared to archived data, U in Kadji Sai particles was present as uraninite (U4O9+y or UO2+x) or Na-zippeite aNa(4)(UO2)(6)[(OH)(10)(SO4)(3)]center dot 4H(2)O), i.e. U minerals with very low solubility. The results suggested that TENORM particles can carry substantial amount of radioactivity, which can be subject to re-suspension, atmospheric transport and water transport. Thus, the potential radioecological and radioanalytical impact of radioactive particles at NORM and TENORM sites worldwide should be taken into account. The present work also demonstrates that radioecological studies should benefit from the use of advanced methods such as synchrotron radiation based techniques. (C) 2012 Elsevier Ltd. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000321177200007 Publication Date 2012-03-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0265-931x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.31 Times cited (down) 16 Open Access
Notes ; We gratefully acknowledge the support provided by the Norwegian Ministry of Foreign Affairs and the European Commission (HASYLAB proposal I-20070051 EC and II-20090184 EC). The authors are indebted to Dr. Karen Appel and Dr. Manuela Borchert, Hasylab for beamline assistance. ; Approved Most recent IF: 2.31; 2013 IF: 3.571
Call Number UA @ admin @ c:irua:109558 Serial 5710
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Author van der Linden, V.; Bultinck, E.; de Ruytter, J.; Schalm, O.; Janssens, K.; Devos, W.; Tiri, W.
Title Compositional analysis of 17-18th century archaeological glass fragments, excavated in Mechelen, Belgium: comparison with data from neighboring cities in the Low Countries Type A1 Journal article
Year 2005 Publication Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms Abbreviated Journal Nucl Instrum Meth B
Volume 239 Issue 1/2 Pages 100-106
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000233514700013 Publication Date 2005-08-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-583X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.109 Times cited (down) 15 Open Access
Notes Approved Most recent IF: 1.109; 2005 IF: 1.181
Call Number UA @ lucian @ c:irua:56068 Serial 444
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Author Scot, V.; Fernandez, J.E.; Vincze, L.; Janssens, K.
Title 3D extension of the Monte Carlo code MCSHAPE for photon-matter interactions in the heterogeneous media Type A1 Journal article
Year 2007 Publication Nuclear instruments & methods in physics research section B-Beam interactions with materiala and atoms Abbreviated Journal
Volume 263 Issue 1 Pages 204-208
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000250798000042 Publication Date 2007-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited (down) 15 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:66755 Serial 5448
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Author Kempenaers, L.; de Koster, C.; van Borm, W.; Janssens, K.
Title Micro-heterogeneity study of trace elements in BCR CRM 680 by means of synchrotron micro-XRF Type A1 Journal article
Year 2001 Publication Fresenius' journal of analytical chemistry Abbreviated Journal
Volume 369 Issue Pages 733-737
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000168522500038 Publication Date 2002-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0937-0633 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited (down) 15 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:34150 Serial 5713
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Author Terzano, R.; Spagnuolo, M.; Medici, L.; Tateo, F.; Vekemans, B.; Janssens, K.; Ruggiero, P.
Title Spectroscopic investigation on the chemical forms of Cu during the synthesis of zeolite X at low temperature Type A1 Journal article
Year 2006 Publication Applied geochemistry Abbreviated Journal Appl Geochem
Volume 21 Issue 6 Pages 993-1005
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000238827500010 Publication Date 2006-05-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0883-2927 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.581 Times cited (down) 15 Open Access
Notes Approved Most recent IF: 2.581; 2006 IF: 1.866
Call Number UA @ admin @ c:irua:59636 Serial 5841
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Author Benito, P.; Monti, M.; de Nolf, W.; Nuyts, G.; Janssens, K.; et al.
Title Improvement in the coating homogeneity in electrosynthesized Rh structured catalysts for the partial oxidation of methane Type A1 Journal article
Year 2015 Publication Catalysis today Abbreviated Journal Catal Today
Volume 246 Issue Pages 154-164
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The precipitation of Rh/Mg/Al and Rh/Al hydroxides on the surface of FeCrAlloy foams by a base electrogeneration method was investigated to improve the properties of the deposited film (homogeneity and composition) and therefore the performances of the structured catalysts, obtained by calcination, in the Catalytic Partial Oxidation of CH4 to syngas. The work focussed on decreasing current gradients within open-cell foam cylinders by increasing the number of electrical contacts from 1 to 3 points to promote a more homogeneous precipitation of the hydroxides. Electrochemical and catalytic tests as well as SEM/EDS and mu-XRFIXRD analyses allowed to correlate the effect of the number of electrical contact points with materials properties. Lastly, syntheses were performed on Pt plates to study the effect of the electrical behaviour and shape of the support on the composition of the film. A more homogeneous coating of the foam surface was achieved by adopting a configuration with 3 contact points since the reduction of nitrates and water molecules that generates the basic media in the vicinity of the support was enhanced. Layer thicknesses up to 5-15 mu m were deposited; however, the sequential precipitation of a film with composition closer to the expected one and a layer enriched in Al and Rh (outer layer) was not avoided. The improvement in the coating gave rise to enhanced performances for a sample prepared at -1.1 V for 3000 s. Contrarily, the low adherence of the outer layer in a sample prepared at -1.2 V for 2000 s during both calcination and catalytic tests may be responsible of the unexpected decrease in catalytic performances. The same sequential precipitation was observed by performing the syntheses on Pt plates, showing that the electrical nature the support did not play a key role on this phenomenon. (C) 2014 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000349998300020 Publication Date 2014-10-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0920-5861 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.636 Times cited (down) 14 Open Access
Notes ; The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, I) is gratefully acknowledged. The authors thank D. Grolimund and C.N. Borca for assisting the mu XRF/XRD conducted experiments at MicroXAS Beamline of SLS Thanks are due to Porvair for supplying FeCrAlloy foams. ; Approved Most recent IF: 4.636; 2015 IF: 3.893
Call Number UA @ admin @ c:irua:124616 Serial 5656
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Author Zanin, L.; Tomasi, N.; Rizzardo, C.; Gottardi, S.; Terzano, R.; Alfeld, M.; Janssens, K.; De Nobili, M.; Mimmo, T.; Cesco, S.
Title Iron allocation in leaves of Fe-deficient cucumber plants fed with natural Fe complexes Type A1 Journal article
Year 2015 Publication Physiologia plantarum Abbreviated Journal Physiol Plantarum
Volume 154 Issue 1 Pages 82-94
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Iron (Fe) sources available for plants in the rhizospheric solution are mainly a mixture of complexes between Fe and organic ligands, including phytosiderophores (PS) and water-extractable humic substances (WEHS). In comparison with the other Fe sources, Fe-WEHS are more efficiently used by plants, and experimental evidences show that Fe translocation contributes to this better response. On the other hand, very little is known on the mechanisms involved in Fe allocation in leaves. In this work, physiological and molecular processes involved in Fe distribution in leaves of Fe-deficient Cucumis sativus supplied with Fe-PS or Fe-WEHS up to 5days were studied combining different techniques, such as radiochemical experiments, synchrotron micro X-ray fluorescence, real-time reverse transcription polymerase chain reaction and in situ hybridization. In Fe-WEHS-fed plants, Fe was rapidly (1day) allocated into the leaf veins, and after 5days, Fe was completely transferred into interveinal cells; moreover, the amount of accumulated Fe was much higher than with Fe-PS. This redistribution in Fe-WEHS plants was associated with an upregulation of genes encoding a ferric(III)-chelate reductase (FRO), a Fe2+ transporter (IRT1) and a natural resistance-associated macrophage protein (NRAMP). The localization of FRO and IRT1 transcripts next to the midveins, beside that of NRAMP in the interveinal area, may suggest a rapid and efficient response induced by the presence of Fe-WEHS in the extra-radical solution for the allocation in leaves of high amounts of Fe. In conclusion, Fe is more efficiently used when chelated to WEHS than PS and seems to involve Fe distribution and gene regulation of Fe acquisition mechanisms operating in leaves.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000353067500007 Publication Date 2014-10-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9317 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.33 Times cited (down) 14 Open Access
Notes ; Research was supported by grants from Italian MIUR (FIRB-Programma 'Futuro in Ricerca') and Free University of Bolzano (TN5056). Synchrotron experiments at HASYLAB were financially supported by the European Community-Research Infrastructure Action under the FP6 'Structuring the European Research Area' Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). We thank Karen Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; Approved Most recent IF: 3.33; 2015 IF: 3.138
Call Number UA @ admin @ c:irua:132500 Serial 5678
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Author Benito, P.; Nuyts, G.; Monti, M.; de Nolf, W.; Fornasari, G.; Janssens, K.; Scavetta, E.; Vaccari, A.
Title Stable Rh particles in hydrotalcite-derived catalysts coated on FeCrAlloy foams by electrosynthesis Type A1 Journal article
Year 2015 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ
Volume 179 Issue Pages 321-332
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Rh-based structured catalysts for the Catalytic Partial Oxidation of CH4 to syngas were prepared by electrosynthesis of Rh/Mg/Al hydrotalcite-type compounds on FeCrAlloy foams and calcination. The effects of Rh content, total metal concentration, and partial replacement of Mg2+ by Ni2+ in the electrolytic solution on coating thickness, Rh speciation, metallic particle size, and catalytic activity were investigated by SEM/EDS, mu-XRF/XANES and tests under diluted and concentrated reaction conditions. The amount of Rh species, present as Mg (RhxAl1-x)(2)O-4, depended on the thickness of the electrosynthesised layer as well as the Rh particle size and dispersion. Smaller and more dispersed particles were obtained by decreasing the Rh concentration in the electrolytic solution from Rh/Mg/Al=11/70/19 to 5/70/25 and 2/70/28 atomic ratio% (a.r.%) and in thinner rather than thicker layers. Despite the improvement in metallic particles features, the CH4 conversion was negatively affected by the low amount of active sites in the coating, the high metal support interaction and possibly the oxidation of metallic particles and carbon formation. A larger amount of solid containing well dispersed Rh particles was deposited by increasing the total metal concentration from 0.03 M to 0.06 M with the Rh/Mg/Al=5/70/25 a.r.%, and the catalytic performances were enhanced. The partial replacement of Mg2+ by Ni2+ gave rise to a very active bimetallic Rh/Ni catalyst, CH4 conversion and selectivity to syngas were above 90%, however, it slightly deactivated with time-on-stream. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000359873800036 Publication Date 2015-05-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0926-3373 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.446 Times cited (down) 14 Open Access
Notes ; The Authors acknowledge M. Salome for helping during the mu XRF/XANES experiments at ID21 Beamline of the ESRF, the Department of Structural Characterisation of CNR-IMM of Bologna for the access to the FEG-SEM facility and Dr F. Ospitali for the scientific support. Thanks are due to Farrel Lytle database for providing the necessary Rh metal spectrum (rhfoil.a99 in http:// ixs.iit.edu/data/FarrelLytledata/). The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, Italy) and the University of Bologna (FARB program) is gratefully acknowledged. ; Approved Most recent IF: 9.446; 2015 IF: 7.435
Call Number UA @ admin @ c:irua:127777 Serial 5846
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Author Anaf, W.; Schalm, O.; Janssens, K.; De Wael, K.
Title Understanding the (in)stability of semiconductor pigments by a thermodynamic approach Type A1 Journal article
Year 2015 Publication Dyes and pigments Abbreviated Journal Dyes Pigments
Volume 113 Issue Pages 409-415
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Several artists pigments are semiconductors. Some of these materials appear stable over time, whereas others already show remarkable signs of degradation after limited time periods. The (in)stability of these pigments can be understood using a thermodynamic approach. For several pigment-related materials, the thermodynamic oxidation and reduction potential (ϕox and ϕred) were determined and evaluated considering the absolute energy positions of the valence and conduction band edges and the water redox potentials. The positions of ϕox and ϕred can be used in a fast screening of the stability of semiconductor pigments towards photoinduced corrosion in an aqueous/humid environment. This theoretical approach corresponds well with experimental data on pigment permanence and degradation phenomena found in literature.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000346543200052 Publication Date 2014-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0143-7208 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.473 Times cited (down) 14 Open Access
Notes ; The authors acknowledge the funding from the Belspo S2-ART project (Belgian Federal Government) SD/RI/04A. ; Approved Most recent IF: 3.473; 2015 IF: 3.966
Call Number UA @ admin @ c:irua:118875 Serial 5885
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Author Ceglia, A.; Nuyts, G.; Cagno, S.; Meulebroeck, W.; Baert, K.; Cosyns, P.; Nys, K.; Thienpont, H.; Janssens, K.; Terryn, H.
Title A XANES study of chromophores : the case of black glass Type A1 Journal article
Year 2014 Publication Analytical methods Abbreviated Journal Anal Methods-Uk
Volume 6 Issue 8 Pages 2662-2671
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract We studied the Fe K-edge X-ray absorption near edge (XANES) spectra of several Roman black glass fragments in order to determine the Fe3+/ΣFe ratio of these materials. The selected archaeological glass samples cover the period 1st5th century AD in nine different sites of the North Western provinces of the Roman Empire. The fragments belong to two different compositional groups demonstrating a diachronic evolution: early Roman HMG (High Magnesia Glass) and Roman Imperial LMG (Low Magnesia Glass). The first group contains natural Fe levels (below 2 wt% as Fe2O3), while the LMG has concentrations above 5 wt%. This difference is also reflected by Fe3+/ΣFe values. Low iron glass was produced under strongly reducing conditions in order to obtain the black colour, with average Fe3+/ΣFe values ≈ 0.17. LMG glass is somewhat more oxidised (Fe3+/ΣFe ≈ 0.40.5). While HMG glass required active control of the furnace environment, LMG was made under ambient atmosphere and its higher oxidation degree is mainly determined by the chemistry of the raw glass.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000333524200032 Publication Date 2014-02-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1759-9660 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.9 Times cited (down) 14 Open Access
Notes ; The authors are grateful to the staff of beamline L in HASYLAB for their helpful support. The research leading to these results has received funding from the European Union Seventh Framework Programme FP7/2007-2013 under grant agreement no. 265010. Support from the University of Antwerp Research Council through GOA Programme “XANES meets ELNES” is gratefully acknowledged. This work was partly supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/F50. We would like to thank M. P. Riccardi and E. Basso of the University of Pavia and R. Falcone of the Stazione Sperimentale del Vetro who provided us with the reference glasses. ; Approved Most recent IF: 1.9; 2014 IF: 1.821
Call Number UA @ admin @ c:irua:116596 Serial 5919
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Author Fredrickx, P.; de Ryck, I.; Janssens, K.; Schryvers, D.; Petit, J.-P.; Döcking, H.
Title EPMA and µ-SRXRF analysis and TEM-based microstructure characterization of a set of Roman glass fragments Type A1 Journal article
Year 2004 Publication X-ray spectrometry Abbreviated Journal X-Ray Spectrom
Volume 33 Issue 5 Pages 326-333
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000223880800002 Publication Date 2004-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0049-8246;1097-4539; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.298 Times cited (down) 13 Open Access
Notes Approved Most recent IF: 1.298; 2004 IF: 1.391
Call Number UA @ lucian @ c:irua:48786 Serial 1076
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