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	Author	Caen, J.; Schalm, O.; van der Snickt, G.; van der Linden, V.; Frederickx, P.; Schryvers, D.; Janssens, K.; Cornelis, E.; van Dyck, D.; Schreiner, M.
	Title	Enamels in stained-glass windows : preparation, chemical composition, microstructure and causes of deterioration			Type	P3 Proceeding
	Year	2005	Publication		Abbreviated Journal
	Volume		Issue		Pages	121-126
	Keywords	P3 Proceeding; Art; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Vision lab
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	Glassac	Place of Publication	Lisbon	Editor
	Language		Wos		Publication Date	0000-00-00
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:112025			Serial	1036
Permanent link to this record



	Author	van der Snickt, G.; Schalm, O.; Caen, J.; Janssens, K.; Schreiner, M.
	Title	Blue enamel on sixteenth- and seventeenth-century window glass : deterioration, microstructure, composition and preparation			Type	A1 Journal article
	Year	2006	Publication	Studies in conservation	Abbreviated Journal	Stud Conserv
	Volume	51	Issue		Pages	212-222
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000241941100006	Publication Date	2014-01-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0039-3630; 2047-0584	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	0.578	Times cited	8	Open Access
	Notes				Approved	Most recent IF: 0.578; 2006 IF: 0.609
	Call Number	UA @ admin @ c:irua:60712			Serial	5492
Permanent link to this record



	Author	de Nolf, W.; Vekemans, B.; Janssens, K.; van der Snickt, G.; Falkenberg, G.
	Title	Pigment identification by scanning μ-XRF/μ-XRD			Type	H3 Book chapter
	Year	2007	Publication		Abbreviated Journal
	Volume		Issue		Pages
	Keywords	H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:64595			Serial	5773
Permanent link to this record



	Author	van der Snickt, G.; de Boeck, A.; Keutgens, K.; Anthierens, D.
	Title	The SALUT project : study of advanced laser techniques for the uncovering of polychromed works of art			Type	P1 Proceeding
	Year	2007	Publication		Abbreviated Journal
	Volume	116	Issue		Pages	151-158 T2 - Proceedings of the 6th International
	Keywords	P1 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In order to find out whether the existing laser systems can be employed to remove superimposed layers of paint on secco wall paintings in a selective way, laser tests were carried out on three types of prepared samples simulating three stratigraphies that are frequently encountered in practice. OM, EPMA, colorimetry, mu Raman, and FT-IR were used to evaluate the results. It was found that Q-switched Nd:YAG lasers emitting at 1,064 nm could be employed to remove unwanted layers of oil paint and limewash, but the treatment of large areas requires implementation of a computer-controlled X-Y-Z station in order to control the parameters. However, the applicability of this technique will remain limited as ablation at the established optimum parameters implied a discoloration of the pigments cinnabar, yellow ochre, and burnt sienna. Moreover, it was observed that no ablation took place when the limewash thickness exceeds 25 mu m. Unwanted layers of acrylic could be removed in an efficient way with an excimer laser emitting at 193 nm.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000252680500018	Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	978-3-540-72129-1; 0930-8989	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:157216			Serial	8491
Permanent link to this record



	Author	de Nolf, W.; Jaroszewicz, J.; van der Snickt, G.; Janssens, K.; Farnell, S.; Klaassen, L.
	Title	Combined micro-XRF/XRPD tomography on historical and modern paint multilayer samples at Beamline L			Type	H3 Book chapter
	Year	2008	Publication		Abbreviated Journal
	Volume		Issue		Pages	1633-1634
	Keywords	H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:74475			Serial	5522
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	Author	Dik, J.; Janssens, K.; van der Snickt, G.; Wallert, A.; Rickers, K.; Falkenberg, G.
	Title	High-E scanning m-XRF experiment on test paintings			Type	H3 Book chapter
	Year	2008	Publication		Abbreviated Journal
	Volume		Issue		Pages	1589-1590
	Keywords	H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:74469			Serial	5638
Permanent link to this record



	Author	van der Snickt, G.; de Nolf, W.; Vekemans, B.; Janssens, K.
	Title	μ-XRF/μ-RS vs. SR μ-XRD for pigment identification in illuminated manuscripts			Type	A1 Journal article
	Year	2008	Publication	Applied physics A : materials science & processing	Abbreviated Journal	Appl Phys A-Mater
	Volume	92	Issue	1	Pages	59-68
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	For the non-destructive identification of pigments and colorants in works of art, in archaeological and in forensic materials, a wide range of analytical techniques can be used. Bearing in mind that every method holds particular limitations, two complementary spectroscopic techniques, namely confocal ì-Raman spectroscopy (ì-RS) and ì-X-ray fluorescence spectroscopy (ì-XRF), were joined in one instrument. The combined ì-XRF and ì-RS device, called PRAXIS unites both complementary techniques in one mobile setup, which allows ì- and in situ analysis. ì-XRF allows one to collect elemental and spatially-resolved information in a non-destructive way on major and minor constituents of a variety of materials. However, the main disadvantages of ì-XRF are the penetration depth of the X-rays and the fact that only elements and not specific molecular combinations of elements can be detected. As a result ì-XRF is often not specific enough to identify the pigments within complex mixtures. Confocal Raman microscopy (ì-RS) can offer a surplus as molecular information can be obtained from single pigment grains. However, in some cases the presence of a strong fluorescence background limits the applicability. In this paper, the concrete analytical possibilities of the combined PRAXIS device are evaluated by comparing the results on an illuminated sheet of parchment with the analytical information supplied by synchrotron radiation ì-X-ray diffraction (SR ì-XRD), a highly specific technique.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000256426000008	Publication Date	2008-03-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0947-8396	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.455	Times cited	56	Open Access
	Notes				Approved	Most recent IF: 1.455; 2008 IF: 1.884
	Call Number	UA @ admin @ c:irua:74465			Serial	5695
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	Author	Aibéo, C.L.; Goffin, S.; Schalm, O.; van der Snickt, G.; Laquière, N.; Eyskens, P.; Janssens, K.
	Title	Micro-Raman analysis for the identification of pigments from 19th and 20th century paintings			Type	A1 Journal article
	Year	2008	Publication	Journal of Raman spectroscopy	Abbreviated Journal	J Raman Spectrosc
	Volume	39	Issue	8	Pages	1091-1098
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In this article, results using confocal µ-Raman to analyse the cross-section of paint samples are presented. Results obtained with light microscopy, scanning electron microscopy (SEM) combined with an energy dispersive X-ray analysis (EDX) and micro-X-ray fluorescence (µ-XRF) are mentioned and compared to the ones obtained with confocal (MRS). In some cases, pigment identification was possible only by combining analytical results from different techniques. The samples were drawn from five paintings belonging to the Academy of Fine Arts of Antwerp, which are part of a collection of 34 paintings made by students from the Academy between 1819 and 1920. Since, on the one hand, the painting techniques and materials, especially pigments, used in this period are still not completely known, and on the other hand, this collection constitutes a very important and reliable resource of information, these paintings were chosen for a systematic investigation. They represent the evolution of painting in Belgium over approximately a century.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000259242100020	Publication Date	2008-05-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0377-0486	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.969	Times cited	28	Open Access
	Notes				Approved	Most recent IF: 2.969; 2008 IF: 3.526
	Call Number	UA @ admin @ c:irua:74467			Serial	5716
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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
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000258448100039	Publication Date	2008-07-29
	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	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



	Author	Schalm, O.; van der Linden, V.; Frederickx, P.; Luyten, S.; van der Snickt, G.; Caen, J.; Schryvers, D.; Janssens, K.; Cornelis, E.; van Dyck, D.; Schreiner, M.
	Title	Enamels in stained glass windows: preparation, chemical composition, microstructure and causes of deterioration			Type	A1 Journal article
	Year	2009	Publication	Spectrochimica acta: part B : atomic spectroscopy	Abbreviated Journal	Spectrochim Acta B
	Volume	64	Issue	8	Pages	812-820
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Vision lab
	Abstract	Stained glass windows incorporating dark blue and purple enamel paint layers are in some cases subject to severe degradation while others from the same period survived the ravages of time. A series of dark blue, greenblue and purple enamel glass paints from the same region (Northwestern Europe) and from the same period (16early 20th centuries) has been studied by means of a combination of microscopic X-ray fluorescence analysis, electron probe micro analysis and transmission electron microscopy with the aim of better understanding the causes of the degradation. The chemical composition of the enamels diverges from the average chemical composition of window glass. Some of the compositions appear to be unstable, for example those with a high concentration of K2O and a low content of CaO and PbO. In other cases, the deterioration of the paint layers was caused by the less than optimal vitrification of the enamel during the firing process. Recipes and chemical compositions indicate that glassmakers of the 1617th century had full control over the color of the enamel glass paints they made. They mainly used three types of coloring agents, based on Co (dark blue), Mn (purple) and Cu (light-blue or greenblue) as coloring elements. Bluepurple enamel paints were obtained by mixing two different coloring agents. The coloring agent for redpurple enamel, introduced during the 19th century, was colloidal gold embedded in grains of lead glass.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000269995300018	Publication Date	2009-06-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0584-8547;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.241	Times cited	28	Open Access
	Notes	Iuap Vi/6; Fwo; Goa			Approved	Most recent IF: 3.241; 2009 IF: 2.719
	Call Number	UA @ lucian @ c:irua:79647			Serial	1035
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	Author	van der Snickt, G.; Dik, J.; Cotte, M.; Janssens, K.; Jaroszewicz, J.; de Nolf, W.; Groenewegen, J.; van der Loeff, L.
	Title	Characterization of a degraded cadmium yellow (CdS) pigment in an oil painting by means of synchrotron radiation based X-ray techniques			Type	A1 Journal article
	Year	2009	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	81	Issue	7	Pages	2600-2610
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	On several paintings of James Ensor (1860−1949), a gradual fading of originally bright yellow areas, painted with the pigment cadmium yellow (CdS), is observed. Additionally, in some areas exposed to light, the formation of small white-colored globules on top of the original paint surface is observed. In this paper the chemical transformation leading to the color change and to the formation of the globules is elucidated. Microscopic X-ray absorption near-edge spectroscopy (ì-XANES) experiments show that sulfur, originally present in sulfidic form (S2−), is oxidized during the transformation to the sulfate form (S6+). Upon formation (at or immediately below the surface), the highly soluble cadmium sulfate is assumed to be transported to the surface in solution and reprecipitates there, forming the whitish globules. The presence of cadmium sulfate (CdSO4·2H2O) and ammonium cadmium sulfate [(NH4)2Cd(SO4)2] at the surface is confirmed by microscopic X-ray diffraction measurements, where the latter salt is suspected to result from a secondary reaction of cadmium sulfate with ammonia. Measurements performed on cross sections reveal that the oxidation front has penetrated into the yellow paint down to ca. 1−2 ìm. The morphology and elemental distribution of the paint and degradation product were examined by means of scanning electron microscopy equipped with an energy-dispersive spectrometer (SEM-EDS) and synchrotron radiation based micro-X-ray fluorescence spectrometry (SR ì-XRF). In addition, ultraviolet-induced visible fluorescence photography (UIVFP) revealed itself to be a straightforward technique for documenting the occurrence of this specific kind of degradation on a macroscale by painting conservators.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000264759400025	Publication Date	2009-03-11
	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	91	Open Access
	Notes				Approved	Most recent IF: 6.32; 2009 IF: 5.214
	Call Number	UA @ admin @ c:irua:76415			Serial	5501
Permanent link to this record



	Author	van der Snickt, G.; Janssens, K.; Schalm, O.; Aibéo, C.; Kloust, H.; Alfeld, M.
	Title	James Ensor's pigment use: artistic and material evolution studied by means of portable X-ray fluorescence spectrometry			Type	A1 Journal article
	Year	2010	Publication	X-ray spectrometry	Abbreviated Journal	X-Ray Spectrom
	Volume	39	Issue	2	Pages	103-111
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In this paper, portable X-ray fluorescence spectrometry (PXRF) was employed as a screening tool for determining and comparing the pigment use in a large series of paintings by the Belgian artist James Ensor (1860-1949). Benefits and drawbacks of PXRF as a method, and the instrument employed, are discussed from a practical, conservation and instrumental perspective. Regardless of several restrictions due to the set-up and/or the analytical method, it appeared feasible to document the evolution with time in Ensor's use of inorganic pigments and to correlate this technical evolution with stylistic developments, Nevertheless, it became clear that a full identification of all materials present can only be done by means of the analysis of (cross-sectioned) samples.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000275959400006	Publication Date	2009-12-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0049-8246	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.298	Times cited	25	Open Access
	Notes	; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The staff of the different museums and private institutions is acknowledged for rendering their assistance to this research, i.e. by making all paintings available for analysis and authorising the publication of the images in this article. Therefore, a word of gratitude to Paul Huvenne, Yolande Deckers, Herwig Todts, Stef Antonissen, Gwen Borms and Lizet Klaassen of the Koninklijk Museum voor Schone Kunsten Antwerpen (KMSKA), Luuk Van der Loeff of the Kroller-Muller Museum in Otterlo and Mireille Engel, Barbara De Jong of the Musea aan Zee (MuZee), Patricia Jaspers of the Dexia bank, Hildegard Van de Velde of the KBC bank and Frederik Leen of the Koninklijke Musea voor Schone Kunsten van Belgie (KMSKB). Special thanks to Xavier Tricot and the other members of the Ensor committee for their valuable feedback. ;			Approved	Most recent IF: 1.298; 2010 IF: 1.661
	Call Number	UA @ admin @ c:irua:82324			Serial	5680
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	Author	Janssens, K.; de Nolf, W.; van der Snickt, G.; Vincze, L.; Vekemans, B.; Terzano, R.; Brenker, F.E.
	Title	Recent trends in quantitative aspects of microscopic X-ray fluorescence analysis			Type	A1 Journal article
	Year	2010	Publication	Trends in analytical chemistry	Abbreviated Journal	Trac-Trend Anal Chem
	Volume	29	Issue	6	Pages	464-478
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000279235000014	Publication Date	2010-03-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0165-9936	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.442	Times cited	48	Open Access
	Notes	; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of FWO (Brussels, Belgium) projects nr. G.0704.08 and G.0179.09 and from the UA-BOF GOA programme. ;			Approved	Most recent IF: 8.442; 2010 IF: 6.602
	Call Number	UA @ admin @ c:irua:83903			Serial	5806
Permanent link to this record



	Author	Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Verbeeck, J.; Tian, H.; Tan, H.; Dik, J.; Radepont, M.; Cotte, M.
	Title	Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples			Type	A1 Journal article
	Year	2011	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	83	Issue	4	Pages	1214-1223
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000287176900011	Publication Date	2011-02-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700;1520-6882;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.32	Times cited	113	Open Access
	Notes	Iuap; Fwo			Approved	Most recent IF: 6.32; 2011 IF: 5.856
	Call Number	UA @ lucian @ c:irua:88794UA @ admin @ c:irua:88794			Serial	632
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	Author	Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Dik, J.; Radepont, M.; Hendriks, E.; Geldof, M.; Cotte, M.
	Title	Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 2 : original paint layer samples			Type	A1 Journal article
	Year	2011	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	83	Issue	4	Pages	1224-1231
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The darkening of the original yellow areas painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is a phenomenon widely observed on several paintings by Vincent van Gogh, such as the famous different versions of Sunflowers. During our previous investigations on artificially aged model samples of lead chromate, we established for the first time that darkening of chrome yellow is caused by reduction of PbCrO4 to Cr2O3·2H2O (viridian green), likely accompanied by the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide]. In the second part of this work, in order to demonstrate that this reduction phenomenon effectively takes place in real paintings, we study original paint samples from two paintings of V. van Gogh. As with the model samples, in view of the thin superficial alteration layers that are present, high lateral resolution spectroscopic methods that make use of synchrotron radiation (SR), such as microscopic X-ray absorption near edge (μ-XANES) and X-ray fluorescence spectrometry (μ-XRF) were employed. Additionally, μ-Raman and mid-FTIR analyses were carried out to completely characterize the samples. On both paint microsamples, the local presence of reduced Cr was demonstrated by means of μ-XANES point measurements. The presence of Cr(III) was revealed in specific areas, in some cases correlated to the presence of Ba(sulfate) and/or to that of aluminum silicate compounds.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000287176900012	Publication Date	2011-02-14
	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	84	Open Access
	Notes	; This research was funded by grants from ESRF (experiment EC-504) and by HASYLAB (experiments 11-20080130 EC and 11-20070157 EC) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Van Gogh Museum, Amsterdam, is acknowledged for their agreeable cooperation and for the authorization to publish the images of the paintings in this article. L.M. was financially supported by the Erasmus Placement in the framework of Lifelong Learning Programme (A.Y. 2009-2010). The EU Community's FP7 Research Infrastructures program under the CHARISMA Project (Grant Agreement 228330) is also acknowledged. ;			Approved	Most recent IF: 6.32; 2011 IF: 5.856
	Call Number	UA @ admin @ c:irua:88795			Serial	5571
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	Author	de Nolf, W.; Dik, J.; van der Snickt, G.; Wallert, A.; Janssens, K.
	Title	High energy X-ray powder diffraction for the imaging of (hidden) paintings			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	5	Pages	910-916
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Over the past few years a number of innovative imaging techniques have been introduced for the visualization of hidden paint layers in Old Master Paintings. These include X-ray fluorescence scanning, TeraHertz imaging, optical coherence tomography and other acoustics-based forms of visualization. All of these techniques are usually a trade-off between their penetrative capability on the one side and their analytical precision in terms of spatial resolution and material identification on the other. Here, we present the first-time use of High-Energy X-ray Powder Diffraction imaging (HE-XRPD) in the study of hidden layers in paintings. As an imaging tool, it combines high-depth sensitivity with fingerprint identification of most inorganic painting materials. The potential as well as some limitations of this technique are demonstrated using model paintings as well as an authentic 16th century painting.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000289731900005	Publication Date	2011-03-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	34	Open Access
	Notes	; ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:89922			Serial	5640
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	Author	van der Snickt, G.; Miliani, C.; Janssens, K.; Brunetti, B.G.; Romani, A.; Rosi, F.; Walter, P.; Castaing, J.; de Nolf, W.; Klaassen, L.; Labarque, I.; Wittermann, R.
	Title	Material analyses of “Christ with singing and music-making Angels”, a late 15th-C panel painting attributed to Hans Memling and assistants : part 1 : non-invasive in situ investigations			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	11	Pages	2216-2229
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In cultural heritage science, compositional data is traditionally obtained from works of art through the analysis of samples by means of various bench-top instruments (scanning electron microscope, Raman spectrometer, etc.). Alternatively, the object can be transported to a laboratory where it may be examined, usually by spectroscopic methods working in reflection mode. However, this paper describes how a complementary set of mobile and portable instruments was deployed in situ to gain a comprehensive view on the materials and related ageing compounds of an (almost) unmovable 15th-C polyptych, prior to and in preparation of the extraction of a limited number of samples. In line with the methodological approach discussed, PXRF was first employed as an efficient screening tool. The ensuing elemental data was supplemented by more specific information on both organic as inorganic materials supplied by reflection near- and mid-FTIR spectroscopy and fluorimetry. In completion, a limited number of diffraction patterns were collected with a mobile XRD instrument in order to identify the constituent crystalline phases in pigments, grounding materials and degradation products. In this way, it could be demonstrated how a rich array of colours was obtained by means of a limited palette of pigments: lead white, lead tin yellow, azurite, natural ultramarine, bone black, vermillion, madder lake, and a green copper-organo complex were detected and situated on the panels. Remarkably, next to chalk also gypsum was found in the ground layer(s) of this Western European easel painting. The relatively large surface of the background was covered with gold leaf; the analyses seem to point towards the labour-intensive water gilding technique. The versatility of this combination of analytical techniques was further illustrated by the accurate characterisation of degradation products affecting the readability and conservation of the painting: the overall presence of a calcium oxalate-based film of variable thickness was established. Nevertheless, further analysis of cross-sectioned samples was considered desirable in order to study the stratigraphy, to gain direct access to altered and sub-imposed layers and to allow highly detailed analysis of micrometric degradation products by state-of-the art techniques (i.e. synchrotron radiation).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000296021800010	Publication Date	2011-09-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	32	Open Access
	Notes	; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0103.04, G.0689.06 and G.0704.08. The staff of the Royal Museum of Fine Arts Antwerp is acknowledged for this pleasant cooperation and the authorisation for the publication of the images in this article. Therefore, a word of gratitude to Paul Huvenne, Yolande Deckers, Stef Antonissen and Gwen Borms. In addition, the authors would like to thank the MOLAB's team operators Chiari Anselmi and Federica Presciutti. MOLAB analyses have been carried out through the support of the EU within the 6th Framework Programme (Contract Eu-ARTECH, RII3-CT-2004-506171). ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:93680			Serial	5705
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	Author	Alfeld, M.; Janssens, K.; Dik, J.; de Nolf, W.; van der Snickt, G.
	Title	Optimization of mobile scanning macro-XRF systems for the in situ investigation of historical paintings			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	5	Pages	899-909
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Elemental distribution maps are of great interest in the study of historical paintings, as they allow to investigate the pigment use of the artist, to image changes made in the painting during or after its creation and in some cases to reveal discarded paintings that were later over painted. Yet a method that allows to record such maps of a broad range of elements in a fast, non-destructive and in situ manner is not yet commonly available; a dedicated mobile scanning XRF instrument might fill this gap. In this paper we present three self-built scanning macro-XRF instruments, each based on the experience gained with its precursor. These instruments are compared in terms of sensitivity and limits of detection, which includes a discussion of the use of polycapillary optics and pinhole collimators as beam defining devices. Furthermore, the imaging capabilities of the instruments are demonstrated in three exemplary cases: (parts of) historical paintings from the 15th to the 19th century are examined. These cases illustrate the value of element specific distribution maps in the study of historical paintings and allow in the case of Vincent van Gogh's Patch of Grass a direct comparison between in situ and synchrotron based scanning macro-XRF.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000289731900004	Publication Date	2011-03-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	107	Open Access
	Notes	; The investigation of the “Triptych of the Seven Sacraments'' was done in collaboration with Griet Steyaert, independent restorer, and Lizet Klaassen, Royal Museum of Fine Arts (Antwerp, Belgium). The investigation of ”Patch of Grass'' was realized in collaboration with Luuk van der Loeff, Kroller-Muller-Museum (Otterlo, The Netherlands). M. Alfeld is a PhD fellowship of the Research Foundation-Flanders (FWO). This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16) NACHO. The text also presents results of GOA "XANES meets ELNES'' (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0103.04, G.0689.06 and G.0704.08. Further, the work presented was sponsored by the Innovational Research Incentives Scheme of the Netherlands Organization for Scientific Research, NWO (proj. no. 016.118.303). ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:89919			Serial	5758
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	Author	Radepont, M.; de Nolf, W.; Janssens, K.; van der Snickt, G.; Coquinot, Y.; Klaassen, L.; Cotte, M.
	Title	The use of microscopic X-ray diffraction for the study of HgS and its degradation products corderoite (\alpha-Hg₃S₂Cl₂), kenhsuite (\gamma-Hg₃S₂Cl₂) and calomel (Hg₂Cl₂) in historical paintings			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	5	Pages	959-968
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Since antiquity, the red pigment mercury sulfide (α-HgS), called cinnabar in its natural form or vermilion red when synthetic, was very often used in frescoes and paintings, even if it was known to suffer occasionally from degradation. The paint hereby acquires a black or silver-grey aspect. The chemical characterization of these alteration products is rather challenging mainly because of the micrometric size and heterogeneity of the surface layers that develop and that are responsible for the color change. Methods such as electron microscopy, synchrotron-based microscopic X-ray fluorescence, microscopic X-ray absorption near edge spectroscopy, Raman microscopy and secondary ion microscopy have been previously employed to identify the (Hg- and S-) compounds present and to study their co-localization. Next to these, also microscopic X-ray diffraction (XRD) (either by making use of laboratory X-ray sources or when used at a synchrotron facility) allows the identification of the crystal phases that are present in degraded HgS paint layers. In this paper we employ these various forms of micro-XRD to analyze degraded red paint in different paintings and compare the results with other X-ray based methods. Whereas the elemental analyses of the degradation products revealed, next to mercury and sulfur, the presence of chlorine, X-ray diffraction allowed the identification, next to α-HgS, of the Hg and S-containing compound calomel (Hg2Cl2) but also of the Hg, S and Cl-containing minerals corderoite (α-Hg3S2Cl2) and kenhsuite (γ-Hg3S2Cl2). These observations are consistent with X-ray absorption spectroscopy measurements performed at the S- and Cl-edges.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000289731900011	Publication Date	2011-03-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	40	Open Access
	Notes	; The authors gratefully acknowledge GOA programme “XANES meets EELS'' (University of Antwerp Research Council), the IUAP VI/P16 programme ”Nacho'' (BELSPO, Brussels, Belgium) and FWO (Brussels, Belgium) projects no. G.0689.06, G.0704.08 and G017909N for financial support, the ESRF for granting beamtime under proposals no. EC442 and EC720, and Gema Martinez-Criado for practical help on ID18F. The KMSKA staff is also gratefully acknowledged for their help and interest. Javier Chillida is thanked for providing us with the Pedralbes samples. The authors are also indebted to the CHARISMA project (grant agreement 228330) for financial support. ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:89927			Serial	5896
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	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	van der Snickt, G.
	Title	James Ensor's pigments studied by means of portable and synchrotron radiation-based X-ray techniques : evolution, context and degradation			Type	Doctoral thesis
	Year	2012	Publication		Abbreviated Journal
	Volume		Issue		Pages	501 p.
	Keywords	Doctoral thesis; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:100628			Serial	8135
Permanent link to this record



	Author	Alfeld, M.; Pedroso, J.V.; van Hommes, M.E.; van der Snickt, G.; Tauber, G.; Blaas, J.; Haschke, M.; Erler, K.; Dik, J.; Janssens, K.
	Title	A mobile instrument for in situ scanning macro-XRF investigation of historical paintings			Type	A1 Journal article
	Year	2013	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	28	Issue	5	Pages	760-767
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Scanning macro-X-ray fluorescence analysis (MA-XRF) is rapidly being established as a technique for the investigation of historical paintings. The elemental distribution images acquired by this method allow for the visualization of hidden paint layers and thus provide insight into the artist's creative process and the painting's conservation history. Due to the lack of a dedicated, commercially available instrument the application of the technique was limited to a few groups that constructed their own instruments. We present the first commercially available XRF scanner for paintings, consisting of an X-ray tube mounted with a Silicon-Drift (SD) detector on a motorized stage to be moved in front of a painting. The scanner is capable of imaging the distribution of the main constituents of surface and sub-surface paint layers in an area of 80 by 60 square centimeters with dwell times below 10 ms and a lateral resolution below 100 mu m. The scanner features for a broad range of elements between Ti (Z = 22) and Mo (Z = 42) a count rate of more than 1000 counts per second (cps)?mass percent and detection limits of 100 ppm for measurements of 1 s duration. Next to a presentation of spectrometric figures of merit, the value of the technique is illustrated through a case study of a painting by Rembrandt's student Govert Flinck (1615-1660).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000317674200019	Publication Date	2013-03-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	106	Open Access
	Notes	; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The text also presents the results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. M. Alfeld receives a Ph. D. fellowship of the Research Foundation-Flanders (FWO). We thank J. Langerock for allowing us to examine the portable altar triptych shown in Fig. 5. ;			Approved	Most recent IF: 3.379; 2013 IF: 3.396
	Call Number	UA @ admin @ c:irua:108517			Serial	5453
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	Author	Monico, L.; Janssens, K.; Miliani, C.; van der Snickt, G.; Brunetti, B.G.; Guidi, M.C.; Radepont, M.; Cotte, M.
	Title	Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 4 : artificial aging of model samples of co-precipitates of lead chromate and lead sulfate			Type	A1 Journal article
	Year	2013	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	85	Issue	2	Pages	860-867
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Previous investigations about the darkening of chrome yellow pigments revealed that this form of alteration is attributable to a reduction of the original Cr(VI) to Cr(III), and that the presence of sulfur-containing compounds, most often sulfates, plays a key role during this process. We recently demonstrated that different crystal forms of chrome yellow pigments (PbCrO4 and PbCr1xSxO4) are present in paintings by Vincent van Gogh. In the present work, we show how both the chemical composition and the crystalline structure of lead chromate-based pigments influence their stability. For this purpose, oil model samples made with in-house synthesized powders of PbCrO4 and PbCr1xSxO4 were artificially aged and characterized. We observed a profound darkening only for those paint models made with PbCr1xSxO4, rich in SO42 (x ≥ 0.4), and orthorhombic phases (>30 wt %). Cr and S K-edge micro X-ray absorption near edge structure investigations revealed in an unequivocal manner the formation of up to about 60% of Cr(III)-species in the outer layer of the most altered samples; conversely, independent of the paint models chemical composition, no change in the S-oxidation state was observed. Analyses employing UVvisible diffuse reflectance and Fourier transform infrared spectroscopy were performed on unaged and aged model samples in order to obtain additional information on the physicochemical changes induced by the aging treatment.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000313668400032	Publication Date	2012-10-10
	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	49	Open Access
	Notes	; This research was supported by grants from ESRF (experiment EC-799), the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16), and the BELSPO-SDD S2-ART (SD/RI/04) project. The text also presents results from GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects G.0704.08 and G.01769.09. The EU FP7 programme CHARISMA (Grant Agreement 228330) and MIUR (PRIN08, Materiali e sistemi innovativi per la conservazione dell'arte contemporanea 2008 FFXXN9) are also acknowledged. ;			Approved	Most recent IF: 6.32; 2013 IF: 5.825
	Call Number	UA @ admin @ c:irua:110471			Serial	5569
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	Author	Alfeld, M.; van der Snickt, G.; Vanmeert, F.; Janssens, K.; Dik, J.; Appel, K.; van der Loeff, L.; Chavannes, M.; Meedendorp, T.; Hendriks, E.
	Title	Scanning XRF investigation of a Flower Still Life and its underlying composition from the collection of the Kröller-Muller Museum			Type	A1 Journal article
	Year	2013	Publication	Applied physics A : materials science & processing	Abbreviated Journal	Appl Phys A-Mater
	Volume	111	Issue	1	Pages	165-175
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000316075700020	Publication Date	2013-01-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0947-8396	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.455	Times cited	35	Open Access
	Notes	; This research was supported by the SSD program of BELSPO, Brussels (project S2-ART). Results are also presented here from Gemeenschappelijke Onderzoeksactie (GOA) 'XANES meets ELNES' (Research Fund, University of Antwerp, Belgium) and from Fonds voor Wetenschappelijk Onderzoek (FWO) (Brussels, Belgium) project Nos. G.0704.08 and G.01769.09. The research leading to these results was funded by the European Community's Seventh Framework Program (FP7/2007-2013) under grant agreement No. 226716 and the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) under the VIDI project “Looking Over the Painter's Shoulder” (grant No. 700.10.426). M. Alfeld is the recipient of a Ph.D. fellowship of the Research Foundation-Flanders (FWO). ;			Approved	Most recent IF: 1.455; 2013 IF: 1.694
	Call Number	UA @ admin @ c:irua:108264			Serial	5826
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	Author	Janssens, K.; Alfeld, M.; van der Snickt, G.; de Nolf, W.; Vanmeert, F.; Radepont, M.; Monico, L.; et al.
	Title	The use of synchrotron radiation for the characterization of artists' pigments and paintings			Type	A1 Journal article
	Year	2013	Publication	Annual review of analytical chemistry	Abbreviated Journal	Annu Rev Anal Chem
	Volume	6	Issue		Pages	399-425
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	We review methods and recent studies in which macroscopic to (sub)microscopic X-ray beams were used for nondestructive analysis and characterization of pigments, paint microsamples, and/or entire paintings. We discuss the use of portable laboratory- and synchrotron-based instrumentation and describe several variants of X-ray fluorescence (XRF) analysis used for elemental analysis and imaging and combined with X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Macroscopic and microscopic (μ-)XRF variants of this method are suitable for visualizing the elemental distribution of key elements in paint multilayers. Technical innovations such as multielement, large-area XRF detectors have enabled such developments. The use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that take place during natural pigment alteration processes. However, synchrotron-based combinations of μ-XRF, μ-XAS, and μ-XRD are suitable for such studies.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000323887500019	Publication Date	2013-06-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1936-1327	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	7.435	Times cited	46	Open Access
	Notes	; ;			Approved	Most recent IF: 7.435; 2013 IF: 7.814
	Call Number	UA @ admin @ c:irua:111315			Serial	5902
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				Thesis
	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
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	Author	Legrand, S.; Vanmeert, F.; van der Snickt, G.; Alfeld, M.; de Nolf, W.; Dik, J.; Janssens, K.
	Title	Examination of historical paintings by state-of-the-art hyperspectral imaging methods : from scanning infra-red spectroscopy to computed X-ray laminography			Type	A1 Journal article
	Year	2014	Publication	Heritage science	Abbreviated Journal
	Volume	2	Issue		Pages	13-11
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The development of advanced methods for non-destructive selective imaging of painted works of art at the macroscopic level based on radiation in the X-ray and infrared range of the electromagnetic spectrum are concisely reviewed. Such methods allow to either record depth-selective, element-selective or species-selective images of entire paintings. Camera-based full field methods (that record the image data in parallel) can be discerned next to scanning methods (that build up distributions in a sequential manner by scanning a beam of radiation over the surface of an artefact). Six methods are discussed: on the one hand, macroscopic X-ray fluorescence and X-ray diffraction imaging and X-ray laminography and on the other hand macroscopic Mid and Near Infrared hyper- and full spectral imaging and Optical Coherence Tomography. These methods can be considered to be improved versions of the well-established imaging methods employed worldwide for examination of paintings, i.e., X-ray radiography and Infrared reflectography. Possibilities and limitations of these new imaging techniques are outlined.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2014-05-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2050-7445	ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:124629			Serial	5619
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	Author	Van der Stighelen, K.; Janssens, K.; van der Snickt, G.; Alfeld, M.; Van Beneden, B.; Demarsin, B.; Proesmans, M.; Marchal, G.; Dik, J.
	Title	Young Anthony van Dyck revisited : a multidisciplinary approach to a portrait once attributed to Peter Paul Rubens			Type	A3 Journal article
	Year	2014	Publication	Art matters : international journal for technical art history	Abbreviated Journal
	Volume	6	Issue		Pages	21-35
	Keywords	A3 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Part of the collection of the Rubens House in Antwerp is a portrait of young Anthony van Dyck, alternatively attributed to Peter Paul Rubens and his pupil Anthony van Dyck. In order to reconstruct the genesis of the portrait in a manner that improves upon past investigations, a number of high-end technological methods, such as X-radiography, X-ray computer tomography, mammographic tomosynthesis and macroscopic X-ray fluorescence, have been employed to render the overpainted layers visible again. The results of the interdisciplinary examinations of the portrait of the youthful Van Dyck are impressive. The combined results allow the later additions to be peeled away until the original composition can be reached. Several pentimenti are easily discernible and refer to a rather immature hand that makes the authorship of Peter Paul Rubens very unlikely. What emerges is a portrait of an ambitious young man with a luxuriant head of hair and a slightly turned-up collar. The hat and cape were added later. The facial features are more recognisable and the execution of the bold curls points irrefutably in the direction of Anthony van Dyck as the author of his own portrait.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:122562			Serial	5922
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	Author	Janssens, K.; Alfeld, M.; Van der Snickt, G.; De Nolf, W.; Vanmeert, F.; Monico, L.; Legrand, S.; Dik, J.; Cotte, M.; Falkenberg, G.; van der Loeff, L.; Leeuwestein, M.; Hendriks, E.
	Title	Examination of Vincent van Gogh's paintings and pigments by means of state-of-the-art analytical methods			Type	H2 Book chapter
	Year	2014	Publication		Abbreviated Journal
	Volume		Issue		Pages	373-403 T2 - Science and art : the painted surface
	Keywords	H2 Book chapter; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Recent studies in which X-ray beams of macroscopic to (sub) microscopic dimensions were used for non-destructive analysis and characterization of pigments, paint micro samples and/or entire paintings by Vincent van Gogh are concisely reviewed. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging as well as with the combined use of X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Microscopic and macroscopic XRF are variants of the method that are well suited to visualize the elemental distribution of key elements, mostly metals, present in paint multi layers, either on the length scale from 1–100 μm inside micro samples taken from paintings or on the 1–100 cm length scale when the (subsurface) distribution of specific pigments in entire paintings is concerned. In the context of the characterization of van Gogh's pigments subject to natural degradation, the use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS and μ-XRD have proven themselves to be very suitable for such studies. Their use is often combined with microscopic Fourier transform infra-red (μ-FTIR) spectroscopy since this method delivers complementary information at more or less the same length scale as the X-ray microprobe techniques. Also in the context of macroscopic imaging of works of art, the complementary use of X-ray based and infra-red based imaging appears very promising; some recent developments are discussed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2020-02-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	978-1-84973-818-7	Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:190782			Serial	7943
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	Author	Monico, L.; Janssens, K.; Hendriks, E.; Vanmeert, F.; van der Snickt, G.; Cotte, M.; Falkenberg, G.; Brunetti, B.G.; Miliani, C.
	Title	Evidence for degradation of the chrome yellows in Van Gogh's sunflowers : a study using noninvasive in situ methods and synchrotron-radiation-based x-ray techniques			Type	A1 Journal article
	Year	2015	Publication	Angewandte Chemie: international edition in English	Abbreviated Journal	Angew Chem Int Edit
	Volume	54	Issue	47	Pages	13923-13927
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	This paper presents firm evidence for the chemical alteration of chrome yellow pigments in Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam). Noninvasive in situ spectroscopic analysis at several spots on the painting, combined with synchrotron-radiation-based X-ray investigations of two microsamples, revealed the presence of different types of chrome yellow used by Van Gogh, including the lightfast PbCrO4 and the sulfur-rich PbCr1-xSxO4 (x approximate to 0.5) variety that is known for its high propensity to undergo photoinduced reduction. The products of this degradation process, i.e., Cr-III compounds, were found at the interface between the paint and the varnish. Selected locations of the painting with the highest risk of color modification by chemical deterioration of chrome yellow are identified, thus calling for careful monitoring in the future.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000367722500009	Publication Date	2015-10-20
	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	; We acknowledge financial support from the Italian MIUR project SICH-PRIN (2010329WPF_001) and BELSPO (Brussels) Project S2-ART (SD04A), GOA “SOLARPAINT” (Research Fund Antwerp University, BOF-2015), and FWO (Brussels) projects G.0C12.13, G.0704.08, G.01769.09. We thank ESRF (EC-1051, HG-26) and DESY (I-20120312 EC) for beamtime grants received. Noninvasive analysis of Sunflowers were supported by the EU FP7 programme CHARISMA (Grant 228330) and the Fund Inbev-Baillet Latour (Brussels). L.M. acknowledges financial support from the CNR Short Term Mobility Programme-2013. We thank Muriel Geldof, Luc Megens, Suzan de Groot (The Netherlands Cultural Heritage Agency, RCE), Chiara Grazia, David Buti (CNR-ISTM and SMAArt Centre), and the staff of the Van Gogh Museum for their collaboration. ;			Approved	Most recent IF: 11.994; 2015 IF: 11.261
	Call Number	UA @ admin @ c:irua:131110			Serial	5617
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