| Records |
| Author |
Alvarez-Martin, A.; Cleland, T.P.; Kavich, G.M.; Janssens, K.; Newsome, G.A. |
| Title |
Rapid evaluation of the debromination mechanism of eosin in oil paint by direct analysis in real time and direct infusion-electrospray ionization mass spectrometry |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
91 |
Issue |
16 |
Pages  |
10856-10863 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Eosin is a synthetic organic colorant prone to fading under the influence of light. On the basis of the growing interest in the understanding of the discoloration mechanism of eosin-based lakes, this study compares the ability of two ultrafast and ultrasensitive mass spectrometry techniques to detect eosin derivatives in complex matrices, such as oil media without the use of conventional separation columns or additional sample preparation protocols. Direct analysis in real time mass spectrometry (DART-MS) and direct infusion electrospray ionization mass spectrometry (DI-ESI-MS) were used to characterize the degradation pathway of eosin in oil media. The analysis protocols developed in this study are applied to discern the degradation mechanism of the lake pigment eosin (comprising the molecule per se complexed to an inorganic substrate) dispersed in linseed oil to create an oil paint. The analysis of oil paints by high resolution MS without an extraction methodology that modifies the system chemistry allowed us to identify the degradation forms without causing any additional fragmentation. Both techniques revealed the primary photodegradation pathway of eosin in linseed oil, and DI-ESI-MS provided additional information on the native conformation of the lake. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
|
| Language |
|
Wos |
000482545300069 |
Publication Date |
2019-07-30 |
| 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 |
3 |
Open Access |
|
| Notes |
; The authors would like to acknowledge the SolarPaint project (GOA program, Antwerp University Research Council) and Smithsonian Institution for financial support. ; |
Approved |
Most recent IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:162879 |
Serial |
5800 |
| Permanent link to this record |
| |
|
| |
| Author |
Monico, L.; Janssens, K.; Vanmeert, F.; Cotte, M.; Brunetti, B.G.; van der Snickt, G.; Leeuwestein, M.; Plisson, J.S.; Menu, M.; Miliani, C. |
| Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : part 5 : effects of nonoriginal surface coatings into the nature and distribution of chromium and sulfur species in chrome yellow paints |
Type |
A1 Journal article |
| Year |
2014 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
86 |
Issue |
21 |
Pages |
10804-10811 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
The darkening of lead chromate yellow pigments, caused by a reduction of the chromate ions to Cr(III) compounds, is known to affect the appearance of several paintings by Vincent van Gogh. In previous papers of this series, we demonstrated that the darkening is activated by light and depends on the chemical composition and crystalline structure of the pigments. In this work, the results of Part 2 are extended and complemented with a new study aimed at deepening the knowledge of the nature and distribution of Cr and S species at the interface between the chrome yellow paint and the nonoriginal coating layer. For this purpose, three microsamples from two varnished paintings by Van Gogh and a waxed low relief by Gauguin (all originally uncoated) have been examined. Because nonoriginal coatings are often present in artwork by Van Gogh and contemporaries, the understanding of whether or not their application has influenced the morphological and/or physicochemical properties of the chrome yellow paint underneath is relevant in view of the conservation of these masterpieces. In all the samples studied, microscopic X-ray fluorescence (mu-XRF) and X-ray absorption near edge structure (mu-XANES) investigations showed that Cr(III)-based alteration products are present in the form of grains inside the coating (generally enriched of S species) and also homogeneously widespread at the paint surface. The distribution of Cr(III) species may be explained by the mechanical friction caused by the coating application by brush that picked up and redistributed the superficial Cr compounds, likely already present in the reduced state as result of the photodegradation process. The analysis of the XANES profiles allowed us to obtain new insights into the nature of the Cr(III) alteration products, that were identified as sulfate-, oxide-, organo-metal-, and chloride-based compounds. Building upon the knowledge acquired through the examination of original paint samples and from the investigation of aged model paints in the last Part 4 paper, in this study we aim to characterize a possible relation between the chemical composition of the coating and the chrome yellow degradation pathways by studying photochemically aged model samples covered with a dammar varnish contaminated with sulfide and sulfate salts. Cr speciation results did not show any evidence of the active role of the varnish and added S species on the reduction process of chrome yellows. |
| Address |
|
| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000344510200043 |
Publication Date |
2014-10-10 |
| 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 |
25 |
Open Access |
|
| Notes |
; This research was supported by the Italian projects PRIN (SICH) and PON (ITACHA). The text also presents results from Interuniversity Attraction Poles Programme Belgian Science Policy (S2-ART project S4DA), GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. ESRF is acknowledged for the grants received (experiments EC-799 and EC-1051). L.M. acknowledges the CNR for the financial support received in the framework of the Short Term Mobility Programme 2013. Thanks are expressed to Ella Hendriks (Van Gogh Museum, Amsterdam) and Muriel Geldof (Cultural Heritage Agency of The Netherlands) for selecting and sharing the information on the cross-section taken from Bank of the Seine. All the staff of the Van Gogh Museum, the Kroller-Muller Museum, and the Musee d'Orsay are acknowledged for the agreeable cooperation. ; |
Approved |
Most recent IF: 6.32; 2014 IF: 5.636 |
| Call Number |
UA @ admin @ c:irua:122100 |
Serial |
5570 |
| Permanent link to this record |
| |
|
| |
| Author |
Mayda, S.; Monico, L.; Krishnan, D.; De Meyer, S.; Cotte, M.; Garrevoet, J.; Falkenberg, G.; Sandu, I.C.A.; Partoens, B.; Lamoen, D.; Romani, A.; Miliani, C.; Verbeeck, J.; Janssens, K. |
| Title |
A combined experimental and computational approach to understanding CdS pigment oxidation in a renowned early 20th century painting |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Chemistry of materials |
Abbreviated Journal |
|
| Volume |
35 |
Issue |
24 |
Pages |
10403-10415 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
Cadmium sulfide (CdS)-based yellow pigments have been used in a number of early 20th century artworks, including The Scream series painted by Edvard Munch. Some of these unique paintings are threatened by the discoloration of these CdS-based yellow oil paints because of the oxidation of the original sulfides to sulfates. The experimental data obtained here prove that moisture and cadmium chloride compounds play a key role in promoting such oxidation. To clarify how these two factors effectively prompt the process, we studied the band alignment between CdS, CdCl2, and Cd-(OH)Cl as well as the radicals center dot OH and H3O center dot by density functional theory (DFT) methods. Our results show that a stack of several layers of Cd-(OH)Cl creates a pocket of positive holes at the Cl-terminated surface and a pocket of electrons at the OH-terminated surface by leading in a difference in ionization energy at both surfaces. The resulting band alignment indicates that Cd-(OH)Cl can indeed play the role of an oxidative catalyst for CdS in a moist environment, thus providing an explanation for the experimental evidence. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
001133000900001 |
Publication Date |
2023-12-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0897-4756; 1520-5002 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
The experimental research on the cadmium yellow powders/paint mock-ups and The Scream (ca. 1910) was financially supported by the European Union, research projects IPERION-CH (H2020-INFRAIA-2014-2015, GA no. 654028) and IPERION-HS (H2020-INFRAIA-2019-1, GA no. 871034) and the project AMIS within the program Dipartimenti di Eccellenza 2018-2022 (funded by MUR and the University of Perugia). For the beamtime grants received, the authors thank the ESRF-ID21 beamline (experiments HG64 and HG95), the DESY-P06 beamline, a member of the Helmholtz Association HGF (experiments I-20130221 EC and I-20160126 EC), and the project CALIPSOplus under the GA no. 730872 from the E.U. Framework Programme for Research and Innovation Horizon 2020. All of the staff of the MUNCH Museum (Conservation Department) is acknowledged for their collaboration. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO – Vlaanderen and the Flemish Government, Department EWI. |
Approved |
no |
| Call Number |
UA @ admin @ c:irua:202836 |
Serial |
8999 |
| Permanent link to this record |
| |
|
| |
| Author |
van der Snickt, G.; Janssens, K.; Dik, J.; de Nolf, W.; Vanmeert, F.; Jaroszewicz, J.; Cotte, M.; Falkenberg, G.; Van der Loeff, L. |
| Title |
Combined use of synchrotron radiation based micro-X-ray fluorescence, micro-X-ray diffraction, micro-X-ray absorption near-edge, and micro-fourier transform infrared spectroscopies for revealing an alternative degradation pathway of the pigment cadmium yellow in a painting by Van Gogh |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
84 |
Issue |
23 |
Pages |
10221-10228 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Over the past years a number of studies have described the instability of the pigment cadmium yellow (CdS). In a previous paper we have shown how cadmium sulfide on paintings by James Ensor oxidizes to CdSO4 center dot H2O. The degradation process gives rise to the fading of the bright yellow color and the formation of disfiguring white crystals that are present on the paint surface in approximately 50 mu m sized globular agglomerations. Here, we study cadmium yellow in the painting “Flowers in a blue vase” by Vincent van Gogh. This painting differs from the Ensor case in the fact that (a) a varnish was superimposed onto the degraded paint surface and (b) the CdS paint area is entirely covered with an opaque crust. The latter obscures the yellow color completely and thus presents a seemingly more advanced state of degradation. Analysis of a cross-sectioned and a crushed sample by combining scanning microscopic X-ray diffraction (mu-XRD), microscopic X-ray absorption near-edge spectroscopy (mu-XANES), microscopic X-ray fluorescence (mu-XRF) based chemical state mapping and scanning microscopic Fourier transform infrared (mu-FT-IR) spectrometry allowed unravelling the complex alteration pathway. Although no crystalline CdSO4 compounds were identified on the Van Gogh paint samples, we conclude that the observed degradation was initially caused by oxidation of the original CdS pigment, similar as for the previous Ensor case. However, due to the presence of an overlying varnish containing lead-based driers and oxalate ions, secondary reactions took place. In particular, it appears that upon the photoinduced oxidation of its sulfidic counterion, the Cd2+ ions reprecipitated at the paint/varnish interface after having formed a complex with oxalate ions that themselves are considered to be degradation products of the resin and/or oil in the varnish. The SO42- anions, for their part, found a suitable reaction partner in Pb2+ ions stemming from a dissolved lead-based siccative that was added to the varnish to promote its drying. The resulting opaque anglesite compound in the varnish, in combination with the underlying CdC2O4 layer at the paint/varnish interface, account for the orange-gray crust that is disfiguring the painting on a macroscopic level. In this way, the results presented in this paper demonstrate how, through a judicious combined use of several microanalytical methods with speciation capabilities, many new insights can be obtained from two minute, but highly complex and heterogeneous paint samples. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000311815300013 |
Publication Date |
2012-08-30 |
| 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 |
59 |
Open Access |
|
| Notes |
; This research was supported by BELSPO via the Interuniversity Attraction Poles Programme (IUAP VI/16) and the S2-ART project (SD/RI/04A) and funded by Grants from the ESRF (EC-442) and PETRA-III (I-20120312 EC). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Kroller-Muller Museum and painting conservators Margje Leeuwestein and Esther Van Duijn are acknowledged for this pleasant cooperation and the authorization for the publication of the images in this article. ; |
Approved |
Most recent IF: 6.32; 2012 IF: 5.695 |
| Call Number |
UA @ admin @ c:irua:105971 |
Serial |
5526 |
| Permanent link to this record |
| |
|
| |
| 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). |
| Address |
|
| Corporate Author |
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Thesis |
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| Publisher |
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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 |
18 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 6.32; 2014 IF: 5.636 |
| Call Number |
UA @ admin @ c:irua:118834 |
Serial |
5593 |
| Permanent link to this record |
| |
|
| |
| Author |
Broers, F.T.H.; Verslype, I.; Bossers, K.W.; Vanmeert, F.; Gonzalez, V.; Garrevoet, J.; van Loon, A.; va Duijn, E.; Krekeler, A.; De Keyser, N.; Steeman, I.; Noble, P.; Janssens, K.; Meirer, F.; Keune, K. |
| Title |
Correlated x-ray fluorescence and ptychographic nano-tomography on Rembrandt's The Night Watch reveals unknown lead “layer” |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Science Advances |
Abbreviated Journal |
|
| Volume |
9 |
Issue |
50 |
Pages |
eadj9394-13 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Art; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
The Night Watch, one of the most famous masterpieces by Rembrandt, is the subject of a large research and conservation project. For the conservation treatment, it is of great importance to understand its current condition. Correlated nano-tomography using x-ray fluorescence and ptychography revealed a-so far unknown-lead-containing “layer”, which likely acts as a protective impregnation layer applied on the canvas before the quartz-clay ground was applied. This layer might explain the presence of lead soap protrusions in areas where no other lead components are present. In addition to the three-dimensional elemental mapping, ptychography visualizes and quantifies components not detectable by hard x-ray fluorescence such as the organic fraction and quartz. The first-time use of this combination of synchrotron-based techniques on a historic paint micro-sample shows it to be an important tool to better interpret the results of noninvasive imaging techniques operating on the macroscale. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
|
| Language |
|
Wos |
001142514700010 |
Publication Date |
2023-12-15 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2375-2548 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
no |
| Call Number |
UA @ admin @ c:irua:203849 |
Serial |
9016 |
| Permanent link to this record |
| |
|
| |
| Author |
Broers, F.T.H.; Janssens, K.; Weker, J.N.; Webb, S.M.; Mehta, A.; Meirer, F.; Keune, K. |
| Title |
Two pathways for the degradation of orpiment pigment (As₂S₃) found in paintings |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
|
| Volume |
145 |
Issue |
16 |
Pages |
8847-8859 |
| Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
Paintings are complex objects containing many different chemical compounds that can react over time. The degradation of arsenic sulfide pigments causes optical changes in paintings. The main degradation product was thought to be white arsenolite (As2O3), but previous research also showed the abundant presence of As(V) species. In this study, we investigate the influence of the presence of a medium on the degradation mechanism of orpiment (As2S3) using synchrotron radiation (SR)-based tomographic transmission X-ray microscopy, SR-based micro-X-ray fluorescence, and Xray absorption near edge structure spectroscopy. Upon direct illumination of dry orpiment powder using UV-visible light, only the formation of As2O3 was observed. When As2S3 was surrounded by a medium and illuminated, As2O3 was only observed in the area directly exposed to light, while As(V) degradation species were found elsewhere in the medium. Without accelerated artificial light aging, As(V)(aq) species are formed and migrate throughout the medium within weeks after preparation. In both scenarios, the As(V) species form via intermediate As(III)(aq) species and the presence of a medium is necessary. As(V)(aq) species can react with available cations to form insoluble metal arsenates, which induces stress within the paint layers (leading to, e.g., cracks and delamination) or can lead to a visual change of the image of the painting. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000974346900001 |
Publication Date |
2023-04-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-7863 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
15 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 15; 2023 IF: 13.858 |
| Call Number |
UA @ admin @ c:irua:196762 |
Serial |
8948 |
| Permanent link to this record |
| |
|
| |
| Author |
Bulska, E.; Wysocka, I.A.; Wierzbicka, M.H.; Proost, K.; Janssens, K.; Falkenberg, G. |
| Title |
In vivo investigation of the distribution and the local speciation of selenium in Allium cepa L. by means of microscopic X-ray absorption near-edge structure spectroscopy and confocal microscopic X-ray fluorescence analysis |
Type |
A1 Journal article |
| Year |
2006 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
78 |
Issue |
22 |
Pages |
7616-7624 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
|
| Address |
|
| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000242021400003 |
Publication Date |
2006-10-10 |
| 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 |
56 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.32; 2006 IF: 5.646 |
| Call Number |
UA @ admin @ c:irua:60714 |
Serial |
5659 |
| Permanent link to this record |
| |
|
| |
| Author |
Vanmeert, F.; Hendriks, E.; van der Snickt, G.; Monico, L.; Dik, J.; Janssens, K. |
| Title |
Chemical Mapping by Macroscopic X-ray Powder Diffraction (MA-XRPD) of Van Gogh's Sunflowers : identification of areas with higher degradation risk |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
| Volume |
57 |
Issue |
25 |
Pages |
7418-7422 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
The discoloration rate of chrome yellow (CY), a class of synthetic inorganic pigments (PbCr1-xSxO4) frequently used by Van Gogh and his contemporaries, strongly depends on its sulfate content and on its crystalline structure (either monoclinic or orthorhombic). Macroscopic X-Ray powder diffraction imaging of selected areas on Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam) revealed the presence of two subtypes of CY: the light-fast monoclinic PbCrO4 (LF-CY) and the light-sensitive monoclinic PbCr1-xSxO4 (x approximate to 0.5; LS-CY). The latter was encountered in large parts of the painting (e.g., in the pale-yellow background and the bright-yellow petals, but also in the green stems and flower hearts), thus indicating their higher risk for past or future darkening. Overall, it is present in more than 50% of the CY regions. Preferred orientation of LS-CY allows observation of a significant ordering of the elongated crystallites along the direction of Van Gogh's brush strokes. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000434949200023 |
Publication Date |
2018-03-02 |
| 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 |
10 |
Open Access |
|
| Notes |
; The authors acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, the GOA Project Solarpaint (University of Antwerp Research Council), and the Interreg Smart*Light project. Raman analyses were performed using the European MOLAB platform, which is financially supported by the Horizon 2020 Programme (IPERION CH Grant 654028). The authors thank the staff of the Van Gogh Museum for their collaboration. ; |
Approved |
Most recent IF: 11.994 |
| Call Number |
UA @ admin @ c:irua:153185 |
Serial |
5517 |
| Permanent link to this record |
| |
|
| |
| Author |
Miliani, C.; Monico, L.; Melo, M.J.; Fantacci, S.; Angelin, E.M.; Romani, A.; Janssens, K. |
| Title |
Photochemistry of Artists' Dyes and Pigments : towards better understanding and prevention of colour change in works of art |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
| Volume |
57 |
Issue |
25 |
Pages |
7324-7334 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
The absorption of light gives a pigment its colour and its reason for being, but it also creates excited states, that is, new molecules with an energy excess that can be dissipated through degradation pathways. Photodegradation processes provoke long-term, cumulative and irreversible colour changes (fading, darkening, blanching) of which the prediction and prevention are challenging tasks. Of all the environmental risks that affect heritage materials, light exposure is the only one that cannot be controlled without any impact on the optimal display of the exhibit. Light-induced alterations are not only associated with the pigment itself but also with its interactions with support/binder and, in turn, are further complicated by the nature of the environmental conditions. In this Minireview we investigate how chemistry, encompassing multi-scale analytical investigations of works of art, computational modelling and physical and chemical studies contributes to improve our prediction of artwork appearance before degradation and to establish effective preventive conservation strategies. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000434949200006 |
Publication Date |
2018-04-26 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
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Edition |
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| ISSN |
1433-7851; 0570-0833 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
11.994 |
Times cited |
10 |
Open Access |
|
| Notes |
; We acknowledge: ACS and APS for the permission to adapt Figure 1c,d; RSC to adapt Figures 1e, 3c,d and 4a; Wiley and IUCr to adapt Figures 3b and 4b-d; for the detail of a Andean textile in Figure 5, Museum of Fine Arts, Boston, USA; for the illuminated initial in Figure 6, Torre do Tombo (ANTT). Financial support from the H2020 project IPERION-CH (GA. 654028) is gratefully acknowledged. ; |
Approved |
Most recent IF: 11.994 |
| Call Number |
UA @ admin @ c:irua:153184 |
Serial |
5769 |
| Permanent link to this record |
| |
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| |
| Author |
Vanmeert, F.; De Keyser, N.; van Loon, A.; Klaassen, L.; Noble, P.; Janssens, K. |
| Title |
Transmission and reflection mode macroscopic x-ray powder diffraction imaging for the noninvasive visualization of paint degradation in still life paintings by Jan Davidsz. de Heem |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
91 |
Issue |
11 |
Pages |
7153-7161 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
The use of noninvasive chemical imaging techniques is becoming more widespread for the study of cultural heritage artifacts. Recently a mobile instrument for macroscopic X-ray powder diffraction (MA-XRPD) scanning was developed, which is capable of visualizing the distribution of crystalline (pigment) phases in quasi-flat-painted artifacts. In this study, MA-XRPD is used in both transmission and reflection mode for the analysis of three 17th century still life paintings, two paintings by Jan Davidsz. de Heem (1606-1684) and one copy painting after De Heem by an unknown artist. MA-XRPD allowed to reveal and map the presence of in situ-formed alteration products. In the works examined, two rare lead arsenate minerals, schultenite (PbHAsO4) and mimetite (Pb-5(AsO4)(3)Cl), were encountered, both at and below the paint surface; they are considered to be degradation products of the pigments realgar (alpha-As4S4) and orpiment (As2S3). In transmission mode, the depletion of lead white, present in the (second) ground layer, could be seen, illustrating the intrusive nature of this degradation process. In reflection mode, several sulfate salts, palmierite (K2Pb(SO4)(2)), syngenite (K2Ca(SO4)(2)center dot H2O), and gypsum (CaSO4 center dot 2H(2)O), could be detected, in particular, at the (top) surface of the copy painting. Estimates for the information depth and sensitivity of both transmission and reflection mode MA-XRPD for various pigments have been made. The possibility of MA-XRPD to allow for noninvasive identification and visualization of alteration products is considered a significant advantage and unique feature of this method. MA-XRPD can thus provide highly relevant information for assessing the conservation state of artworks and could guide possible future restoration treatments. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000470793800031 |
Publication Date |
2019-05-10 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
|
Edition |
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| ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.32 |
Times cited |
5 |
Open Access |
|
| Notes |
; The authors acknowledge financial support from BELSPO (Brussels) S2-ART and METOX projects, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, and the GOA Project Solarpaint (University of Antwerp Research Council). The authors thank the Rijksmuseum, the Royal Museum of Fine Arts Antwerp, and their staff for the collaborations. ; |
Approved |
Most recent IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:160245 |
Serial |
5882 |
| Permanent link to this record |
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| |
| Author |
Terzano, R.; Spagnuolo, M.; Vekemans, B.; de Nolf, W.; Janssens, K.; Falkenberg, G.; Ruggiero, P. |
| Title |
Assessing the origin and fate of CR, Ni, Cu, Zn, Ph, and V in industrial polluted soil by combined microspectroscopic techniques and bulk extraction methods |
Type |
A1 Journal article |
| Year |
2007 |
Publication |
Environmental science & technology |
Abbreviated Journal |
|
| Volume |
41 |
Issue |
19 |
Pages |
6762-6769 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
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| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000249840600024 |
Publication Date |
2007-08-29 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
61 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:66622 |
Serial |
5481 |
| Permanent link to this record |
| |
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| |
| Author |
Monico, L.; Sorace, L.; Cotte, M.; de Nolf, W.; Janssens, K.; Romani, A.; Miliani, C. |
| Title |
Disclosing the binding medium effects and the pigment solubility in the (photo)reduction process of chrome yellows (PbCrO4/PbCr1-xSxO4) |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
ACS Omega |
Abbreviated Journal |
|
| Volume |
4 |
Issue |
4 |
Pages |
6607-6619 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
The darkening due to chemical alteration of chrome yellows (PbCrO4/PbCr1-xSxO4) is a phenomenon threatening a large number of 19th-20th century paintings, including the Amsterdam Sunflowers by Vincent van Gogh. Our earlier studies have proven that the alteration is due to a Cr(VI) -> Cr(III) reduction with Cr(V)-species that are formed as long-lived intermediates and that bCr(1-x)S(x)O(4) (0 < x <= 0.8) types undergo reduction more readily than monoclinic, S-free, PbCrO4. In this context, there is still lack of knowledge about the effects of the chemical properties of the binding medium (i.e., chemical composition and drying process) and the solubility of chrome yellows on the overall reduction pathways. Here, we study a series of naturally and photochemically aged mock-up paints prepared by mixing chrome yellow powders (PbCrO4/PbCr0.2S0.8O4) with either linseed oil or a water-based acrylic emulsion as the binding medium. Equivalent paints made up of the highly soluble K2CrO4 were also investigated and used as benchmarks to provide a more in-depth understanding of the influence of the solubility on the chromate reduction pathways in the two different binders. A combination of synchrotron radiation-based Cr K-edge X-ray absorption near edge structure (XANES), electron paramagnetic resonance (EPR), and UV-Visible spectroscopy measurements shows that: (1) the Cr(VI) reduction results from the interaction between the pigment and the binder; (2) the process is more significant in oil, giving rise to Cr(V)- and Cr(III)-species as well as oxidized organic compounds; (3) the lightfastness of the chrome yellow pigment is enhanced in the acrylic binder; and (4) the tendency toward chromium reduction increases with increasing solubility of the pigment. Based on our findings, we propose a scheme for the mechanism of the (photo)reduction process of chrome yellows in the oil and acrylic binder. Overall, our results provide new insights into the factors driving the degradation of lead chromate-based paints in artworks and contribute to the development of strategies for preserving them over time. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000466552500057 |
Publication Date |
2019-04-10 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
|
Edition |
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| ISSN |
2470-1343 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
4 |
Open Access |
|
| Notes |
; The research was financially supported by the European research project IPERION-CH, funded by the European Commission, H2020-INFRAIA-2014-2015 (grant agreement n. 654028), and by the project AMIS, within the program Dipartimenti di Eccellenza 2018-2022, funded by MIUR and University of Perugia. The University of Perugia is also acknowledged for financial support under the program “Ricerca di Base 2017”. L.S. acknowledges the financial support of Ente CRF. For the beamtime grants received, we thank the ESRF (experiment no. HG64 and in-house beamtimes). ; |
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:160416 |
Serial |
5577 |
| Permanent link to this record |
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| |
| Author |
Vanmeert, F.; de Nolf, W.; Dik, J.; Janssens, K. |
| Title |
Macroscopic X-ray powder diffraction scanning : possibilities for quantitative and depth-selective parchment analysis |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
90 |
Issue |
11 |
Pages |
6445-6452 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
At or below the surface of painted works of art, valuable information is present that provides insights into an objects past, such as the artists technique and the creative process that was followed or its conservation history but also on its current state of preservation. Various noninvasive techniques have been developed over the past 2 decades that can probe this information either locally (via point analysis) or on a macroscopic scale (e.g., full-field imaging and raster scanning). Recently macroscopic X-ray powder diffraction (MA-XRPD) mapping using laboratory X-ray sources was developed. This method can visualize highly specific chemical distributions at the macroscale (dm(2)). In this work we demonstrate the synergy between the quantitative aspects of powder diffraction and the noninvasive scanning capability of MA-XRPD highlighting the potential of the method to reveal new types of information. Quantitative data derived from a 15th/16th century illuminated sheet of parchment revealed three lead white pigments with different hydrocerussite-cerussite compositions in specific pictorial elements, while quantification analysis of impurities in the blue azurite pigment revealed two distinct azurite types: one rich in barite and one in quartz. Furthermore, on the same artifact, the depth-selective possibilities of the method that stem from an exploitation of the shift of the measured diffraction peaks with respect to reference data are highlighted. The influence of different experimental parameters on the depth-selective analysis results is briefly discussed. Promising stratigraphic information could be obtained, even though the analysis is hampered by not completely understood variations in the unit cell dimensions of the crystalline pigment phases. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000434893200020 |
Publication Date |
2018-04-06 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.32 |
Times cited |
6 |
Open Access |
|
| Notes |
; The authors thank Incoatec GmbH for giving us the opportunity to test the I mu S Cu X-ray source. We acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, and GOA Project Solarpaint (University of Antwerp Research Council). Photo Copyright Geert Van der Snickt, 2008 for the photograph of the illuminated manuscript in the TOC graphic. ; |
Approved |
Most recent IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:151994 |
Serial |
5702 |
| Permanent link to this record |
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| |
| Author |
Vanmeert, F.; de Nolf, W.; De Meyer, S.; Dik, J.; Janssens, K. |
| Title |
Macroscopic X-ray powder diffraction scanning, a new method for highly selective chemical imaging of works of art : instrument optimization |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
90 |
Issue |
11 |
Pages |
6436-6444 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
In the past decade macroscopic X-ray fluorescence imaging (MA-XRF) has become established as a method for the noninvasive investigation of flat painted surfaces, yielding large scale elemental maps. MA-XRF is limited by a lack of specificity, only allowing for indirect pigment identification based on the simultaneous presence of chemical elements. The high specificity of X-ray powder diffraction (XRPD) mapping is already being exploited at synchrotron facilities for investigations at the (sub)microscopic scale, but the technique has not yet been employed using lab sources. In this paper we present the development of a novel MA-XRPD/XRF instrument based on a laboratory X-ray source. Several combinations of X-ray sources and area detectors are evaluated in terms of their spatial and angular resolution and their sensitivity. The highly specific imaging capability of the combined MA-XRPD/XRF instrument is demonstrated on a 15th/16th century illuminated manuscript directly revealing the distribution of a large number of inorganic pigments, including the uncommon yellow pigment massicot (o-PbO). The case study illustrates the wealth of new mapping information that can be obtained in a noninvasive manner using the laboratory MA-XRPD/XRF instrument. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000434893200019 |
Publication Date |
2018-04-06 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.32 |
Times cited |
11 |
Open Access |
|
| Notes |
; The authors thank the persons involved at Incoatec GmbH, imXPAD SAS and Dectris Ltd. for loaning us some of their products over the past years. We acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” Project and GOA Project Solarpaint (University of Antwerp Research Council). Photo Copyright Geert Van der Snickt, 2008 for the photograph of the illuminated manuscript in the TOC graphic. ; |
Approved |
Most recent IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:151993 |
Serial |
5701 |
| Permanent link to this record |
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| |
| Author |
Dik, J.; Janssens, K.; van der Snickt, G.; van der Loeff, L.; Rickers, K.; Cotte, M. |
| Title |
Visualization of a lost painting by Vincent van Gogh using synchrotron radiation based X-ray fluorescence elemental mapping |
Type |
A1 Journal article |
| Year |
2008 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
80 |
Issue |
16 |
Pages |
6436-6442 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Vincent van Gogh (1853−1890), one of the founding fathers of modern painting, is best known for his vivid colors, his vibrant painting style, and his short but highly productive career. His productivity is even higher than generally realized, as many of his known paintings cover a previous composition. This is thought to be the case in one-third of his early period paintings. Van Gogh would often reuse the canvas of an abandoned painting and paint a new or modified composition on top. These hidden paintings offer a unique and intimate insight into the genesis of his works. Yet, current museum-based imaging tools are unable to properly visualize many of these hidden images. We present the first-time use of synchrotron radiation based X-ray fluorescence mapping, applied to visualize a womans head hidden under the work Patch of Grass by Van Gogh. We recorded decimeter-scale, X-ray fluorescence intensity maps, reflecting the distribution of specific elements in the paint layers. In doing so we succeeded in visualizing the hidden face with unprecedented detail. In particular, the distribution of Hg and Sb in the red and light tones, respectively, enabled an approximate color reconstruction of the flesh tones. This reconstruction proved to be the missing link for the comparison of the hidden face with Van Goghs known paintings. Our approach literally opens up new vistas in the nondestructive study of hidden paint layers, which applies to the oeuvre of Van Gogh in particular and to old master paintings in general. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000258448100039 |
Publication Date |
2008-07-29 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.32 |
Times cited |
178 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.32; 2008 IF: 5.712 |
| Call Number |
UA @ admin @ c:irua:74466 |
Serial |
5906 |
| Permanent link to this record |
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| Author |
Terzano, R.; Spagnuolo, M.; Medici, L.; Vekemans, B.; Vincze, L.; Janssens, K.; Ruggiero, P. |
| Title |
Copper stabilization by zeolite synthesis in polluted soils treated with coal fly ash |
Type |
A1 Journal article |
| Year |
2005 |
Publication |
Environmental science and technology |
Abbreviated Journal |
Environ Sci Technol |
| Volume |
39 |
Issue |
16 |
Pages |
6280-6287 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
This study deals with the process of zeolite formation in an agricultural soil artificially polluted by high amounts of Cu (15 mg of Cu/g of soil dry weight) and treated with fused coal fly ash at 30 and 60 degrees C and how this process affects the mobility and availability of the metal. As a consequence of the treatment, the amount of dissolved Cu, and thus its mobility, was strongly reduced, and the percentage of the metal stabilized in the solid phase increased over time, reaching values of 30% at 30 degrees C and 40% at 60 degrees C. The physicochemical phenomena responsible for Cu stabilization in the solid phase have been evaluated by EDTA sequential extractions and synchrotron radiation based X-ray microanalytical techniques. These techniques were used for the visualization of the spatial distribution and the speciation of Cu in and/or on the neo-formed zeolite particles. In particular, micro XRF (X-ray fluorescence) tomography showed direct evidence that Cu can be entrapped as clusters inside the porous zeolitic structures while,mu-XANES (X-ray absorption near edge structure) spectroscopy determinations revealed Cu to be present mainly as Cu(II) hydroxide and Cu(II) oxide. The reported results could be useful as a basic knowledge for planning new technologies for the on site physicochemical stabilization of heavy metals in heavily polluted soils. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000231203100053 |
Publication Date |
2005-08-11 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0013-936x; 1520-5851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.198 |
Times cited |
39 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.198; 2005 IF: 4.054 |
| Call Number |
UA @ admin @ c:irua:103658 |
Serial |
5560 |
| Permanent link to this record |
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| Author |
Avranovich Clerici, E.; De Meyer, S.; Vanmeert, F.; Legrand, S.; Monico, L.; Miliani, C.; Janssens, K. |
| Title |
Multi-scale X-ray imaging of the pigment discoloration processes triggered by chlorine compounds in the Upper Basilica of Saint Francis of Assisi |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Molecules: a journal of synthetic chemistry and natural product chemistry |
Abbreviated Journal |
|
| Volume |
28 |
Issue |
16 |
Pages |
6106-6123 |
| Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
In this paper, the chromatic alteration of various types of paints, present on mural painting fragments derived from the vaults of The Upper Basilica of Saint Francis of Assisi in Italy (12th-13th century), is studied using synchrotron radiation. Six painted mural fragments, several square centimeters in size, were available for analysis, originating from the ceiling paintings attributed to Cimabue and Giotto; they correspond to originally white, blue/green, and brown/yellow/orange areas showing discoloration. As well as collecting macroscopic X-ray fluorescence and diffraction maps from the entire fragments in the laboratory and at the SOLEIL synchrotron, corresponding paint cross-sections were also analyzed using microscopic X-ray fluorescence and powder diffraction mapping at the PETRA-III synchrotron. Numerous secondary products were observed on the painted surfaces, such as (a) copper tri-hydroxychloride in green/blue areas; (b) corderoite and calomel in vermillion red/cinnabar-rich paints; (c) plattnerite and/or scrutinyite assumed to be oxidation products of (hydro)cerussite (2PbCO(3)center dot Pb(OH)(2)) in the white areas, and (d) the calcium oxalates whewellite and weddellite. An extensive presence of chlorinated metal salts points to the central role of chlorine-containing compounds during the degradation of the 800-year-old paint, leading to, among other things, the formation of the rare mineral cumengeite (21PbCl(2)center dot 20Cu(OH) (2) center dot 6H(2)O). |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
001056388600001 |
Publication Date |
2023-08-17 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
|
Edition |
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| ISSN |
1420-3049 |
ISBN |
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Additional Links |
UA library record; WoS full record |
| Impact Factor |
4.6 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 4.6; 2023 IF: 2.861 |
| Call Number |
UA @ admin @ c:irua:199265 |
Serial |
8902 |
| Permanent link to this record |
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| Author |
Koirala, B.; Rasti, B.; Bnoulkacem, Z.; De Lima Ribeiro, A.; Madriz, Y.; Herrmann, E.; Gestels, A.; De Kerf, T.; Janssens, K.; Steenackers, G.; Gloaguen, R.; Scheunders, P. |
| Title |
An extensive multisensor hyperspectral benchmark datasets of intimate mixtures of mineral powders |
Type |
P1 Proceeding |
| Year |
2023 |
Publication |
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Abbreviated Journal |
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| Volume |
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Issue |
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Pages |
5890-5893
T2 - IGARSS 2023 - 2023 IEEE Internation |
| Keywords |
P1 Proceeding; Vision lab; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
Since many materials behave as heterogeneous intimate mixtures with which each photon interacts differently, the relationship between spectral reflectance and material composition is very complex. Quantitative validation of spectral unmixing algorithms requires high-quality ground truth fractional abundance data, which are very difficult to obtain.In this work, we generated a comprehensive hyperspectral dataset of intimate mineral powder mixtures by homogeneously mixing five different clay powders (Kaolin, Roof clay, Red clay, mixed clay, and Calcium hydroxide). In total 325 samples were prepared. Among the 325 samples, 60 mixtures were binary, 150 were ternary, 100 were quaternary, and 15 were quinary. For each mixture (and pure clay powder), reflectance spectra are acquired by 13 different sensors, with a broad wavelength range between the visible and the long-wavelength infrared regions (i.e., between 350 nm and 15385 nm) and with a large variation in sensor types, platforms, and acquisition conditions. We will make this dataset public, to be used by the community for the validation of nonlinear unmixing methodologies (https://github.com/VisionlabUA/Multisensor_datasets) |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
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Publication Date |
2023-10-20 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
979-83-503-2010-7 |
ISBN |
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Additional Links |
UA library record |
| Impact Factor |
|
Times cited |
|
Open Access |
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| Notes |
|
Approved |
no |
| Call Number |
UA @ admin @ c:irua:201596 |
Serial |
9035 |
| Permanent link to this record |
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| Author |
Tadić, M.; Peeters, F.M.; Janssens, K.L.; Korkusinski, M.; Hawrylak, P. |
| Title |
Strain and band edges in single and coupled cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
92 |
Issue |
10 |
Pages |
5819-5829 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
A comparative study is made of the strain distribution in cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots as obtained from isotropic elasticity theory, the anisotropic continuum mechanical model, and from atomistic calculations. For the isotropic case, the recently proposed approach [J. H. Davies, J. Appl. Phys. 84, 1358 (1998)] is used, while the finite-element method, the valence force field method, and Stillinger-Weber potentials are employed to calculate the strain in anisotropic structures. We found that all four methods result in strain distributions of similar shapes, but with notable quantitative differences inside the dot and near the disk-matrix boundary. The variations of the diagonal strains with the height of the quantum dot, with fixed radius, as calculated from all models, are almost linear. Furthermore, the energies of the band edges in the two types of quantum dots are extracted from the multiband effective-mass theory by inserting the strain distributions as obtained by the four models. We demonstrated that all strain models produce effective potentials for the heavy and light holes which agree very well inside the dot. A negligible anisotropy of all normal strains in the (x,y) plane is found, which, providing the axial symmetry of the kinetic part of the multiband effective-mass Hamiltonian, justifies the use of the axial approximation. Strain propagation along the vertical direction is also considered with the aim to study the influence of strain on the electron coupling in stacks of quantum dots. We found that the interaction between the strain fields of the individual quantum dots makes the effective quantum wells for the electrons in the conduction band shallower, thereby counteracting the quantum mechanical coupling. (C) 2002 American Institute of Physics. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000178987200036 |
Publication Date |
2002-11-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.068 |
Times cited |
73 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.068; 2002 IF: 2.281 |
| Call Number |
UA @ lucian @ c:irua:103327 |
Serial |
3164 |
| Permanent link to this record |
| |
|
| |
| Author |
Byrnes, I.; Rossbach, L.M.; Brede, D.A.; Grolimund, D.; Sanchez, D.F.; Nuyts, G.; Cuba, V.; Reinoso-Maset, E.; Salbu, B.; Janssens, K.; Oughton, D.; Scheibener, S.; Teien, H.-C.; Lind, O.C. |
| Title |
Synchrotron-based X-ray fluorescence imaging elucidates uranium toxicokinetics in Daphnia magna |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
ACS nano |
Abbreviated Journal |
|
| Volume |
17 |
Issue |
6 |
Pages |
5296-5305 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
A combination of synchrotron-based elemental anal-ysis and acute toxicity tests was used to investigate the biodistribution and adverse effects in Daphnia magna exposed to uranium nanoparticle (UNP, 3-5 nm) suspensions or to uranium reference (Uref) solutions. Speciation analysis revealed similar size distributions between exposures, and toxicity tests showed com-parable acute effects (UNP LC50: 402 mu g L-1 [336-484], Uref LC50: 268 mu g L-1 [229-315]). However, the uranium body burden was 3 -to 5-fold greater in UNP-exposed daphnids, and analysis of survival as a function of body burden revealed a similar to 5-fold higher specific toxicity from the Uref exposure. High-resolution X-ray fluorescence elemental maps of intact, whole daphnids from sublethal, acute exposures of both treatments revealed high uranium accumulation onto the gills (epipodites) as well as within the hepatic ceca and the intestinal lumen. Uranium uptake into the hemolymph circulatory system was inferred from signals observed in organs such as the heart and the maxillary gland. The substantial uptake in the maxillary gland and the associated nephridium suggests that these organs play a role in uranium removal from the hemolymph and subsequent excretion. Uranium was also observed associated with the embryos and the remnants of the chorion, suggesting uptake in the offspring. The identification of target organs and tissues is of major importance to the understanding of uranium and UNP toxicity and exposure characterization that should ultimately contribute to reducing uncertainties in related environmental impact and risk assessments. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000960129800001 |
Publication Date |
2023-03-15 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
17.1 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 17.1; 2023 IF: 13.942 |
| Call Number |
UA @ admin @ c:irua:196061 |
Serial |
8631 |
| Permanent link to this record |
| |
|
| |
| Author |
Rossbach, L.M.; Brede, D.A.; Nuyts, G.; Cagno, S.; Olsson, R.M.S.; Oughton, D.H.; Falkenberg, G.; Janssens, K.; Lind, O.C. |
| Title |
Synchrotron XRF analysis identifies cerium accumulation colocalized with pharyngeal deformities in CeO₂ NP-exposed caenorhabditis elegans |
Type |
A1 Journal article |
| Year |
2022 |
Publication |
Environmental science and technology |
Abbreviated Journal |
Environ Sci Technol |
| Volume |
56 |
Issue |
8 |
Pages |
5081-5089 |
| Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
A combination of synchrotron radiation-based elementalimaging, in vivo redox status analysis, histology, and toxic responses was usedto investigate the uptake, biodistribution, and adverse effects of Cenanoparticles (CeO2NP; 10 nm; 0.5-34.96 mg Ce L-1) or Ce(NO3)3(2.3-26 mg Ce L-1)inCaenorhabditis elegans. Elemental mapping of theexposed nematodes revealed Ce uptake in the alimentary canal prior todepuration. Retention of CeO2NPs was low compared to that of Ce(NO3)3in depurated individuals. X-rayfluorescence (XRF) mapping showed that Cetranslocation was confined to the pharyngeal valve and foregut. Ce(NO3)3exposure significantly decreased growth, fertility, and reproduction, causedslightly reduced fecundity. XRF mapping and histological analysis revealedsevere tissue deformities colocalized with retained Ce surrounding thepharyngeal valve. Both forms of Ce activated the sod-1 antioxidant defense,particularly in the pharynx, whereas no significant effects on the cellular redox balance were identified. The CeO2NP-induceddeformities did not appear to impair the pharyngeal function or feeding ability as growth effects were restricted to Ce(NO3)3exposure. The results demonstrate the utility of integrated submicron-resolution SR-based XRF elemental mapping of tissue-specificdistribution and adverse effect analysis to obtain robust toxicological evaluations of metal-containing contaminants. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000793137500039 |
Publication Date |
2022-04-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0013-936x; 1520-5851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
11.4 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 11.4 |
| Call Number |
UA @ admin @ c:irua:188662 |
Serial |
7216 |
| Permanent link to this record |
| |
|
| |
| 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 |
|
| Address |
|
| 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 |
21 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.32; 2002 IF: 5.094 |
| Call Number |
UA @ admin @ c:irua:39871 |
Serial |
5734 |
| Permanent link to this record |
| |
|
| |
| Author |
van der Snickt, G.; Dubois, H.; Sanyova, J.; Legrand, S.; Coudray, A.; Glaude, C.; Postec, M.; van Espen, P.; Janssens, K. |
| Title |
Large-area elemental imaging reveals Van Eyck's original paint layers on the Ghent altarpiece (1432), rescoping its conservation treatment |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
| Volume |
56 |
Issue |
17 |
Pages |
4797-4801 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
A combination of large-scale and micro-scale elemental imaging, yielding elemental distribution maps obtained by, respectively non-invasive macroscopic X-ray fluorescence (MA-XRF) and by secondary electron microscopy/energy dispersive X-ray analysis (SEM-EDX) and synchrotron radiation-based micro-XRF (SR m-XRF) imaging was employed to reorient and optimize the conservation strategy of van Eyck's renowned Ghent Altarpiece. By exploiting the penetrative properties of X-rays together with the elemental specificity offered by XRF, it was possible to visualize the original paint layers by van Eyck hidden below the overpainted surface and to simultaneously assess their condition. The distribution of the high-energy Pb-L and Hg-L emission lines revealed the exact location of hidden paint losses, while Fe-K maps demonstrated how and where these lacunae were filled-up using an iron-containing material. The chemical maps nourished the scholarly debate on the overpaint removal with objective, chemical arguments, leading to the decision to remove all skillfully applied overpaints, hitherto interpreted as work by van Eyck. MA-XRF was also employed for monitoring the removal of the overpaint during the treatment phase. To gather complementary information on the in-depth layer build-up, SEM-EDX and SR mu-XRF imaging was used on paint cross sections to record microscale elemental maps. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000398576000019 |
Publication Date |
2017-03-23 |
| 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 |
11 |
Open Access |
|
| Notes |
; This research was supported by the Baillet Latour fund, the Belgian Science Policy Office (Projects MO/39/011) and the Gieskes-Strijbis fund. The authors are also indebted to the BOF-GOA SOLAR Paint project of the University of Antwerp Research Council. The church wardens of the cathedral of St. Bavo and their chairman L. Collin are acknowledged for this agreeable collaboration. We also wish to thank conservators L. Depuydt, B. De Volder, F. Rosier, N. Laquiere and G. Steyaert as well as the members of the international committee. We are indebted to Prof. Em. A. Van Grevenstein-Kruse. ; |
Approved |
Most recent IF: 11.994 |
| Call Number |
UA @ admin @ c:irua:142376 |
Serial |
5688 |
| Permanent link to this record |
| |
|
| |
| Author |
Koirala, B.; Rasti, B.; Bnoulkacem, Z.; de Lima Ribeiro, A.; Madriz, Y.; Herrmann, E.; Gestels, A.; De Kerf, T.; Lorenz, S.; Fuchs, M.; Janssens, K.; Steenackers, G.; Gloaguen, R.; Scheunders, P. |
| Title |
A multisensor hyperspectral benchmark dataset for unmixing of intimate mixtures |
Type |
A1 Journal article |
| Year |
2024 |
Publication |
IEEE sensors journal |
Abbreviated Journal |
|
| Volume |
24 |
Issue |
4 |
Pages |
4694-4710 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Vision lab; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
Optical hyperspectral cameras capture the spectral reflectance of materials. Since many materials behave as heterogeneous intimate mixtures with which each photon interacts differently, the relationship between spectral reflectance and material composition is very complex. Quantitative validation of spectral unmixing algorithms requires high-quality ground truth fractional abundance data, which are very difficult to obtain. In this work, we generated a comprehensive laboratory ground truth dataset of intimately mixed mineral powders. For this, five clay powders (Kaolin, Roof clay, Red clay, mixed clay, and Calcium hydroxide) were mixed homogeneously to prepare 325 samples of 60 binary, 150 ternary, 100 quaternary, and 15 quinary mixtures. Thirteen different hyperspectral sensors have been used to acquire the reflectance spectra of these mixtures in the visible, near, short, mid, and long-wavelength infrared regions (350-15385) nm. Overlaps in wavelength regions due to the operational ranges of each sensor and variations in acquisition conditions resulted in a large amount of spectral variability. Ground truth composition is given by construction, but to verify that the generated samples are sufficiently homogeneous, XRD and XRF elemental analysis is performed. We believe these data will be beneficial for validating advanced methods for nonlinear unmixing and material composition estimation, including studying spectral variability and training supervised unmixing approaches. The datasets can be downloaded from the following link: https://github.com/VisionlabHyperspectral/Multisensor_datasets. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
|
Publication Date |
2023-12-28 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1530-437x; 1558-1748 |
ISBN |
|
Additional Links |
UA library record |
| Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
no |
| Call Number |
UA @ admin @ c:irua:203094 |
Serial |
9059 |
| Permanent link to this record |
| |
|
| |
| Author |
Hillen, M.; Legrand, S.; Dirkx, Y.; Janssens, K.; van der Snickt, G.; Caen, J.; Steenackers, G. |
| Title |
Cluster analysis of IR thermography data for differentiating glass types in historical leaded-glass windows |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Applied Sciences-Basel |
Abbreviated Journal |
Appl Sci-Basel |
| Volume |
10 |
Issue |
12 |
Pages |
4255-13 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp Cultural Heritage Sciences (ARCHES); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Infrared thermography is a fast, non-destructive and contactless testing technique which is increasingly used in heritage science. The aim of this study was to assess the ability of infrared thermography, in combination with a data clustering approach, to differentiate between the different types of historical glass that were included in a colorless leaded-glass windows during previous restoration interventions. Inspection of the thermograms and the application of two data mining techniques on the thermal data, i.e., k-means clustering and hierarchical clustering, allowed identifying different groups of window panes that show a different thermal behavior. Both clustering approaches arrive at similar groupings of the glass with a clear separation of three types. However, the lead cames that hold the glass panes appear to have a substantial impact on the thermal behavior of the surrounding glass, thus preventing classification of the smallest glass panes. For the larger panes, this was not a critical issue as the center of the glass remained unaffected. Subtle visual color differences between panes, implying a variation in coloring metal ions, was not always distinguished by IRT. Nevertheless, data clustering assisted infrared thermography shows potential as an efficient and swift method for documenting the material intervention history of leaded-glass windows during or in preparation of conservation treatments. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000549351800001 |
Publication Date |
2020-06-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2076-3417 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.7 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.7; 2020 IF: 1.679 |
| Call Number |
UA @ admin @ c:irua:170012 |
Serial |
7674 |
| Permanent link to this record |
| |
|
| |
| Author |
Basile, F.; Benito, P.; Bugani, S.; de Nolf, W.; Fornasari, G.; Janssens, K.; Morselli, L.; Scavetta, E.; Tonelli, D.; Vaccari, A. |
| Title |
Combined use of synchrotron-radiation-based imaging techniques for the characterization of structured catalysts |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
| Volume |
20 |
Issue |
23 |
Pages |
4117-4126 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Active-phase-coated metallic supports as structured catalysts are gaining attention in endothermic and exothermic processes because they improve heat transfer. The deposition of a well-adhered and stable catalyst layer on the metallic support constitutes an important feature for the successful application of the final material. In this work, coating of FeCrAlY foams is performed by a one-step electrosynthesis-deposition of hydrotalcite-type compounds, precursors of catalysts active in endothermic steam methane reforming. The catalysts are studied at different length scales by using, for the first time, a combination of several techniques: SEM/EDS and X-ray fluorescence, X-ray powder diffraction and absorption-tomography experiments on the micro- and nanoscales at a synchrotron facility. The results show that the morphology of the coating depends on the synthesis conditions and that the catalyst may be described as Ni metal crystallites dispersed on γ-Al2O3, homogeneously coating the FeCrAlY foam. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000285392900010 |
Publication Date |
2010-09-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
24 |
Open Access |
|
| Notes |
; The authors give thanks to Dr. Cloetens, for helping during the absorption tomography experiments, performed at ID19 of the ESRF; and P. Blauet and R. Toucolou, for helping during the mu-XRF/XRPD and nano-XRF experiments at ID22 and ID22-NI of the ESRF. The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, Italy) is gratefully acknowledged. ; |
Approved |
Most recent IF: 12.124; 2010 IF: 8.508 |
| Call Number |
UA @ admin @ c:irua:85834 |
Serial |
5525 |
| Permanent link to this record |
| |
|
| |
| Author |
Benito, P.; de Nolf, W.; Nuyts, G.; Janssens, K.; et al. |
| Title |
Role of coating-metallic support interaction in the properties of electrosynthesized Rh-based structured catalysts |
Type |
A1 Journal article |
| Year |
2014 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
| Volume |
4 |
Issue |
10 |
Pages |
3779-3790 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Rh-structured catalysts for the catalytic partial oxidation of CH4 to syngas were prepared by electrosynthesis of Rh-containing hydrotalcite-type (HT) compounds on FeCrAlloy foams followed by calcination at 900 degrees C. During the calcination the simultaneous decomposition of the layered HT structure and formation of the protective FeCrAlloy outer shell in alumina occurred. Here, we studied the role of the coating-metallic support interaction in the properties of the catalysts after calcination, H-2 reduction, and catalytic tests, by a combination of electron (FEG-SEM/EDS) and synchrotron X-ray (XRF/XRPD and XRF/XANES) microscopic techniques. The characterization of crystalline phases in the metallic support and coating and distribution of Rh active species was carried out on several samples prepared by modifying the Rh content in the electrolytic solution (Rh/Mg/Al = 11.0/70.0/19.0, 5.0/70.0/25.0, 0/70.0/30.0 atomic ratio). A sample was also prepared with no aluminum in the electrolytic solution (Rh/Mg/Al = 13.6/86.4/0.0 atomic ratio) and calcined at 550 and 900 degrees C. The interaction between the elements of the metallic support and the catalytic coating increased the film adhesion during the thermal treatment and catalytic tests and modified the catalyst crystalline phases. A chemical reaction between Al corning from the foam and Mg in the coating occurred during calcination at high temperature leading to the formation of spinel phases in which rhodium is solved, together with some Rh2O3 and Rh. The metallic support was oxidized forming the corundum scale and chromium oxides, moreover t-Al2O3 was identified. For the Rh11.0Mg70.0Al19.0 catalyst the inclusion of Rh in the spinel phase decreased its reducibility in the H-2 pretreatment. The reduction continued during catalytic tests by feeding diluted CH4/O-2/He gas mixtures, evidenced by the catalyst activation. While under concentrated gas mixtures the deactivation occurred, probably by oxidation. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000345735200053 |
Publication Date |
2014-09-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2155-5435 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
10.614 |
Times cited |
13 |
Open Access |
|
| Notes |
; The authors thank the scientists who assisted during the conducted experiments: D. Grolimund and C. N. Borca for the mu XRF/XRPD experiments performed at MicroXAS Beamline of SLS, M. Janousch for the mu XRF/XANES experiments at Phoenix Beamline of the SLS, M. Salome for the mu XRE/XANES experiments at ID21 Beamline of the ESRF, and I. Guerra for the FEG-SEM/EDS experiments at Granada University. Thanks must go to Porvair for supplying FeCrAlloy foams. The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, I) is gratefully acknowledged. ; |
Approved |
Most recent IF: 10.614; 2014 IF: 9.312 |
| Call Number |
UA @ admin @ c:irua:122215 |
Serial |
5820 |
| Permanent link to this record |
| |
|
| |
| Author |
Vanmeert, F.; van der Snickt, G.; Janssens, K. |
| Title |
Plumbonacrite identified by X-ray powder diffraction tomography as a missing link during degradation of red lead in a Van Gogh painting |
Type |
A1 Journal article |
| Year |
2015 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
| Volume |
54 |
Issue |
12 |
Pages |
3607-3610 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Red lead, a semiconductor pigment used by artists since antiquity, is known to undergo several discoloration phenomena. These transformations are either described as darkening of the pigment caused by the formation of either plattnerite (β-PbO2) or galena (PbS) or as whitening by which red lead is converted into anglesite (PbSO4) or (hydro)cerussite (2 PbCO3⋅Pb(OH)2; PbCO3). X-ray powder diffraction tomography, a powerful analytical method that allows visualization of the internal distribution of different crystalline compounds in complex samples, was used to investigate a microscopic paint sample from a Van Gogh painting. A very rare lead mineral, plumbonacrite (3 PbCO3⋅ Pb(OH)2⋅PbO), was revealed to be present. This is the first reported occurrence of this compound in a painting dating from before the mid 20th century. It constitutes the missing link between on the one hand the photoinduced reduction of red lead and on the other hand (hydro)cerussite, and thus sheds new light on the whitening of red lead. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000351178300008 |
Publication Date |
2015-02-20 |
| 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 |
24 |
Open Access |
|
| Notes |
; The authors acknowledge L. Van der Loeff and M. Leeuwestein (Kroller-Muller Museum) for providing the paint sample. We thank Dr. J. Jaroszewicz (WUT) for performing the CT measurements. This research was carried out at the light source PETRA III at DESY, a member of the Helmholtz Association (HGF). We thank Dr. G. Falkenberg and the members of his team for their assistance in using beam line P06. We acknowledge financial support from the University of Antwerp GOA projects “XANES meets EELS” and “SOLARPaint”, as well as from BELSPO (Brussels) Project S2-ART and FWO (Brussels) project “ESRF-Dubble”. ; |
Approved |
Most recent IF: 11.994; 2015 IF: 11.261 |
| Call Number |
UA @ admin @ c:irua:124620 |
Serial |
5774 |
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| Author |
Monico, L.; Cartechini, L.; Rosi, F.; Chieli, A.; Grazia, C.; De Meyer, S.; Nuyts, G.; Vanmeert, F.; Janssens, K.; Cotte, M.; De Nolf, W.; Falkenberg, G.; Sandu, I.C.A.; Tveit, E.S.; Mass, J.; De Freitas, R.P.; Romani, A.; Miliani, C. |
| Title |
Probing the chemistry of CdS paints in The Scream by in situ noninvasive spectroscopies and synchrotron radiation x-ray techniques |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Science Advances |
Abbreviated Journal |
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| Volume |
6 |
Issue |
20 |
Pages |
eaay3514 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
The degradation of cadmium sulfide (CdS)-based oil paints is a phenomenon potentially threatening the iconic painting The Scream (ca. 1910) by Edvard Munch (Munch Museum, Oslo) that is still poorly understood. Here, we provide evidence for the presence of cadmium sulfate and sulfites as alteration products of the original CdS-based paint and explore the external circumstances and internal factors causing this transformation. Macroscale in situ noninvasive spectroscopy studies of the painting in combination with synchrotron-radiation x-ray microspectroscopy investigations of a microsample and artificially aged mock-ups show that moisture and mobile chlorine compounds are key factors for promoting the oxidation of CdS, while light (photodegradation) plays a less important role. Furthermore, under exposure to humidity, parallel/secondary reactions involving dissolution, migration through the paint, and recrystallization of water-soluble phases of the paint are associated with the formation of cadmium sulfates. |
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Wos |
000533573300009 |
Publication Date |
2020-05-16 |
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| ISSN |
2375-2548 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.6 |
Times cited |
4 |
Open Access |
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| Notes |
; The research was financially supported by the European research project IPERION-CH, funded by the European Commission, H2020-INFRAIA-2014-2015 (grant agreement no. 654028); the project AMIS, within the program Dipartimenti di Eccellenza 2018-2022 (funded by MIUR and University of Perugia); and the program “Ricerca di Base 2017” (funded by University of Perugia). S.D.M. and K.J. acknowledge the GOA Project SolarPaint from the University of Antwerp Research Council and projects G056619N and G054719N from FWO (Brussels). F.V. and K.J. acknowledge support from Interreg Project Smart*Light and thank BELSPO (Brussels) for financial support via FED-tWIN mandate PRF055. L.M. acknowledges the Erasmus+ program (Staff Mobility for training, A. Y. 2018 to 2019) of the European Commission. In situ noninvasive analyses were performed using the European MOLAB platform, which is financially supported by the European project IPERION-CH. For the beamtime grants received, the authors thank the ESRF-ID21 beamline (experiment nos. HG32, HG64, and HG95), DESY-P06 beamline, a member of the Helmholtz Association HGF (experiment nos. I-20130221 EC and I-20160126 EC), and the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. ; |
Approved |
Most recent IF: 13.6; 2020 IF: NA |
| Call Number |
UA @ admin @ c:irua:169519 |
Serial |
6585 |
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