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	Author	Allegretta, I.; Legrand, S.; Alfeld, M.; Gattullo, C.E.; Porfido, C.; Spagnuolo, M.; Janssens, K.; Terzano, R.
	Title	SEM-EDX hyperspectral data analysis for the study of soil aggregates			Type	A1 Journal article
	Year	2022	Publication	Geoderma: an international journal of soil science	Abbreviated Journal	Geoderma
	Volume	406	Issue		Pages
	Keywords	A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	Scanning electron microscopy coupled with microanalysis (SEM-EDX) is an important analytical tool for the morphological and chemical characterization of different types of materials. In many applications, SEM-EDX elemental maps are usually used and processed as images, thus flattening and reducing the spectroscopic information contained in EDX hyperspectral data cubes. The exploitation of the full hyperspectral dataset could be indeed very useful for the study of complex matrices like soil. In order to maximize the information attainable by SEM-EDX data cubes analysis, the software package “Datamuncher Gamma” was implemented and applied to study soil aggregates. By using this approach, different phases (silicates, aluminosilicates, Ca-carbonates, Ca-phosphates, organic matter, iron oxides) inside soil aggregates were successfully identified and segmented. The advantages of this method over the common ROI imaging approach are presented. Finally, this method was used to compare different aggregates in a Cr-polluted soil and understand their possible pedological history. The present method can be used for the analysis of every type of SEM-EDX data cubes, allowing its application to different types of samples and fields of study.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000708893700026	Publication Date	2021-10-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0016-7061	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.1	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 6.1
	Call Number	UA @ admin @ c:irua:182493			Serial	7207
Permanent link to this record



	Author	Alvarez-Martin, A.; Newsome, G.A.; Janssens, K.
	Title	High-resolution mass spectrometry and nontraditional mass defect analysis of brominated historical pigments			Type	A1 Journal article
	Year	2021	Publication	Analytical Chemistry	Abbreviated Journal	Anal Chem
	Volume	93	Issue	44	Pages	14851-14858
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	The implementation of high-resolution mass spectrometry systems offers new possibilities for the analysis of complex art samples such as historical oil paintings. However, these multicomponent systems generate large and complex data sets that require advanced visualization tools to aid interpretation, especially when no chromatographic separation is performed. In the context of this research, it was crucial to propose a data analysis tool to identify the products generated during the synthesis, drying, and aging of historical pigments. This study reports for the first time a nontraditional mass defect analysis of oil paint samples containing a fugitive brominated-organic pigment, eosin or geranium lake, by using direct infusion electrospray ionization in combination with a high-resolution Orbitrap mass spectrometer. The use of nontraditional Kendrick mass defect plots is presented in this study as a processing and visualization tool to recognize brominated species based on their specific mass defect and isotope pattern. The results demonstrate that this approach could provide valuable molecular compositional information on the degradation pathways of this pigment. We anticipate that mass defect analysis will become highly relevant in future degradation studies of many more historical organic pigments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000718171600037	Publication Date	2021-10-29
	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		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:182347			Serial	8038
Permanent link to this record



	Author	Monico, L.; Prati, S.; Sciutto, G.; Catelli, E.; Romani, A.; Balbas, D.Q.; Li, Z.; De Meyer, S.; Nuyts, G.; Janssens, K.; Cotte, M.; Garrevoet, J.; Falkenberg, G.; Tardillo Suarez, V.I.; Tucoulou, R.; Mazzeo, R.
	Title	Development of a multi-method analytical approach based on the combination of synchrotron radiation X-ray micro-analytical techniques and vibrational micro-spectroscopy methods to unveil the causes and mechanism of darkening of “fake-gilded” decorations in a Cimabue painting			Type	A1 Journal article
	Year	2022	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	37	Issue	1	Pages	114-129
	Keywords	A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	Redox processes activated by environmental factors have been identified as the main cause of the chromatic alterations of a number of artists' pigments, including the yellow pigment orpiment (As2S3). Although a general comprehension of the mechanisms has been provided through characterization of degradation compounds of As2S3, experimental evidences to prove how other paint components and how different environmental agents influence the formation pathways of specific secondary compounds are still lacking. Thus, it becomes fundamental to develop a methodological strategy which enable achieving a discrimination among the causes affecting the chemical stability of more heterogenous As2S3-based paints and defining the mechanism through which the alteration establishes and evolves, with the ultimate goal of optimizing the preventive conservation measures of unique masterpieces. In this paper, we propose a comprehensive multi-material and multi-method approach based on the combination of synchrotron radiation X-ray micro-analytical techniques (i.e., X-ray diffraction, X-ray fluorescence and X-ray absorption near edge structure spectroscopy at S K-/Ag L-3-/As K-edges) and vibrational micro-spectroscopy methods to unveil the causes and mechanism of darkening of “fake-gilded” decorations in tempera paintings, originally consisting of an unusual mixture of As2S3 and metallic silver (Ag-0). Such degradation process is a not yet understood phenomenon threatening a series of Old Master paintings, including those by the Italian painters Cimabue and Pietro Lorenzetti. The high specificity, sensitivity and lateral resolution of the employed analytical methods allowed providing first-time evidence for the presence of black acanthite (alpha-Ag2S), mimetite [Pb-5(AsO4)(3)Cl] and syngenite [K2Ca(SO4)(2)center dot H2O] as degradation products of the “fake-gilded” decorations in the Maesta by Cimabue (Church of Santa Maria dei Servi, Bologna, Italy). Furthermore, the study of the painting combined with that of tempera paint mock-ups permitted to explore and define the environmental agents and internal factors causing the darkening, by proving that: (i) Ag-0 and moisture are key-factors for triggering the transformation of As2S3 to alpha-Ag2S and As-oxides; (ii) S2--ions arising from the degradation of As2S3 are the main responsible for the formation of alpha-Ag2S; (iii) light exposure strengthens the tendency of the paint components towards alteration. Based on our findings, we finally propose a degradation mechanism of As2S3/Ag-0-based tempera paints.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000722353400001	Publication Date	2021-11-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.4	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.4
	Call Number	UA @ admin @ c:irua:184871			Serial	7142
Permanent link to this record



	Author	Derks, K.; van der Snickt, G.; Legrand, S.; van der Stighelen, K.; Janssens, K.
	Title	The dark halo technique in the oeuvre of Michael Sweerts and other Flemish and Dutch baroque painters. A 17th c. empirical solution to mitigate the optical 'simultaneous contrast' effect?			Type	A1 Journal article
	Year	2022	Publication	Heritage science	Abbreviated Journal
	Volume	10	Issue	1	Pages	5
	Keywords	A1 Journal article; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	Although the topic is rarely addressed in literature, a significant number of baroque paintings exhibit dark, halo-like shapes around the contours of the dramatis personae. Close examination of both finished and unfinished works suggests that this intriguing feature was a practical tool that helped the artist in the early painting stages. When applying the final brushwork, the halo lost its function, with some artists undertaking efforts to hide it. Although their visibility might not have been intended by the artists, today this dark paint beneath the surface is partially visible through the upper paint layers. Moreover, the disclosure of many halos using infrared photography (IRP), infrared reflectography (IRR) and macro X-ray fluorescence imaging (MA-XRF), additional to those that can be observed visually, suggests that this was a common and established element of 17th-century painting practice in Western Europe. Building on an existing hypothesis, we argue that halos can be considered as a solution to an optical problem that arose when baroque painters reversed the traditional, 15th- and 16th-century painting sequence of working from background to foreground. Instead, they started with the dominant parts of a composition, such as the face of a sitter. In that case, a temporary halo can provide the essential tonal reference to anticipate the chromatic impact of the final dark colored background on the adjacent delicate carnations. In particular, we attempt to clarify the prevalence of dark halos as a response to optical effects such as 'simultaneous contrast' and 'the crispening effect', described in literature only centuries later. As such, the recently termed 'ring condition' can be seen as the present-day equivalent of the 'halo solution' that was seemingly empirically or intuitively developed by 17th-century artists. Modern studies in visual perception proves that by laying a black ring around a target color, the optical impact of a surrounding color can be efficiently neutralized. Finally, by delving into works by Michael Sweerts, it becomes clear that resourceful artists might have adapted the halo technique and the underlying principles to their individual challenges, such as dealing with differently colored grounds.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000739965700001	Publication Date	2022-01-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2050-7445	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.5	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 2.5
	Call Number	UA @ admin @ c:irua:185458			Serial	7217
Permanent link to this record



	Author	Monico, L.; Rosi, F.; Vivani, R.; Cartechini, L.; Janssens, K.; Gauquelin, N.; Chezganov, D.; Verbeeck, J.; Cotte, M.; D'Acapito, F.; Barni, L.; Grazia, C.; Buemi, L.P.; Andral, J.-L.; Miliani, C.; Romani, A.
	Title	Deeper insights into the photoluminescence properties and (photo)chemical reactivity of cadmium red (CdS_1-xSe_x) paints in renowned twentieth century paintings by state-of-the-art investigations at multiple length scales			Type	A1 Journal article
	Year	2022	Publication	The European Physical Journal Plus	Abbreviated Journal	Eur Phys J Plus
	Volume	137	Issue	3	Pages	311
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	Cadmium red is the name used for denoting a class of twentieth century artists' pigments described by the general formula CdS1-xSex. For their vibrant hues and excellent covering power, a number of renowned modern and contemporary painters, including Jackson Pollock, often used cadmium reds. As direct band gap semiconductors, CdS1-xSex compounds undergo direct radiative recombination (with emissions from the green to orange region) and radiative deactivation from intragap trapping states due to crystal defects, which give rise to two peculiar red-NIR emissions, known as deep level emissions (DLEs). The positions of the DLEs mainly depend on the Se content of CdS1-xSex; thus, photoluminescence and diffuse reflectance vis-NIR spectroscopy have been profitably used for the non-invasive identification of different cadmium red varieties in artworks over the last decade. Systematic knowledge is however currently lacking on what are the parameters related to intrinsic crystal defects of CdS1-xSex and environmental factors influencing the spectral properties of DLEs as well as on the overall (photo)chemical reactivity of cadmium reds in paint matrixes. Here, we present the application of a novel multi-length scale and multi-method approach to deepen insights into the photoluminescence properties and (photo)chemical reactivity of cadmium reds in oil paintings by combining both well established and new non-invasive/non-destructive analytical techniques, including macro-scale vis-NIR and vibrational spectroscopies and micro-/nano-scale advanced electron microscopy mapping and X-ray methods employing synchrotron radiation and conventional sources. Macro-scale vis-NIR spectroscopy data obtained from the in situ non-invasive analysis of nine masterpieces by Gerardo Dottori, Jackson Pollock and Nicolas de Stael allowed classifying the CdS1-xSex-paints in three groups, according to the relative intensity of the two DLE bands. These outcomes, combined with results from micro-/nano-scale electron microscopy mapping and X-ray analysis of a set of CdS1-xSex powders and artificially aged paint mock-ups, indicated that the relative intensity of DLEs is not affected by the morphology, microstructure and local atomic environment of the pigment particles but it is influenced by the presence of moisture. Furthermore, the extensive study of artificially aged oil paint mock-ups permitted us to provide first evidence of the tendency of cadmium reds toward photo-degradation and to establish that the conversion of CdS1-xSex to CdSO4 and/or oxalates is triggered by the oil binding medium and moisture level and depends on the Se content. Based on these findings, we could interpret the localized presence of CdSO4 and cadmium oxalate as alteration products of the original cadmium red paints in two paintings by Pollock.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000765807600002	Publication Date	0000-00-00
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2190-5444	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.4	Times cited	3	Open Access	OpenAccess
	Notes	g The research was financially supported by the EU FP7 and Horizon 2020 Projects CHARISMA (FP7-INFRASTRUCTURES, GA No. 228330), IPERION-CH (H2020-INFRAIA-2014-2015, GA No. 654028), IPERION-HS (H2020-INFRAIA-2019-1, GA No. 871034) and ESTEEM3 (Research and innovation programme, GA No. 823717) and the Italian project AMIS (Dipartimenti di Eccellenza 2018–2022, funded by MIUR and Perugia University). For the beamtime grants received, we thank ESRF-ID21 (Experiment No. HG156 and in-house beamtimes) and the CERIC-ERIC Research Infrastructure for the investigations at ESRF-BM08 (LISA) beamline (Proposal Id: 20207042). D.C. acknowledges TOP/BOF funding of the University of Antwerp.; esteem3reported; esteem3TA			Approved	Most recent IF: 3.4
	Call Number	UA @ admin @ c:irua:187375			Serial	7060
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	Author	Cotte, M.; Gonzalez, V.; Vanmeert, F.; Monico, L.; Dejoie, C.; Burghammer, M.; Huder, L.; de Nolf, W.; Fisher, S.; Fazlic, I.; Chauffeton, C.; Wallez, G.; Jimenez, N.; Albert-Tortosa, F.; Salvado, N.; Possenti, E.; Colombo, C.; Ghirardello, M.; Comelli, D.; Avranovich Clerici, E.; Vivani, R.; Romani, A.; Costantino, C.; Janssens, K.; Taniguchi, Y.; McCarthy, J.; Reichert, H.; Susini, J.
	Title	The “Historical Materials BAG” : a new facilitated access to synchrotron X-ray diffraction analyses for cultural heritage materials at the European Synchrotron Radiation Facility			Type	A1 Journal article
	Year	2022	Publication	Molecules: a journal of synthetic chemistry and natural product chemistry	Abbreviated Journal	Molecules
	Volume	27	Issue	6	Pages	1997-21
	Keywords	A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	The European Synchrotron Radiation Facility (ESRF) has recently commissioned the new Extremely Brilliant Source (EBS). The gain in brightness as well as the continuous development of beamline instruments boosts the beamline performances, in particular in terms of accelerated data acquisition. This has motivated the development of new access modes as an alternative to standard proposals for access to beamtime, in particular via the “block allocation group” (BAG) mode. Here, we present the recently implemented “historical materials BAG”: a community proposal giving to 10 European institutes the opportunity for guaranteed beamtime at two X-ray powder diffraction (XRPD) beamlines-ID13, for 2D high lateral resolution XRPD mapping, and ID22 for high angular resolution XRPD bulk analyses-with a particular focus on applications to cultural heritage. The capabilities offered by these instruments, the specific hardware and software developments to facilitate and speed-up data acquisition and data processing are detailed, and the first results from this new access are illustrated with recent applications to pigments, paintings, ceramics and wood.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000776369800001	Publication Date	2022-03-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1420-3049	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.6	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 4.6
	Call Number	UA @ admin @ c:irua:188053			Serial	7218
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	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	De Keyser, N.; Broers, F.; Vanmeert, F.; De Meyer, S.; Gabrieli, F.; Hermens, E.; van der Snickt, G.; Janssens, K.; Keune, K.
	Title	Reviving degraded colors of yellow flowers in 17th century still life paintings with macro- and microscale chemical imaging			Type	A1 Journal article
	Year	2022	Publication	Science Advances	Abbreviated Journal
	Volume	8	Issue	23	Pages	1-12
	Keywords	A1 Journal article; Engineering sciences. Technology; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	Over time, artist pigments are prone to degradation, which can decrease the readability of the artwork or notably change the artist's intention. In this article, the visual implication of secondary degradation products in a degraded yellow rose in a still life painting by A. Mignon is discussed as a case study. A multimodal combination of chemical and optical imaging techniques, including noninvasive macroscopic x-ray powder diffraction (MA-XRPD) and macroscopic x-ray fluorescence imaging, allowed us to gain a 3D understanding of the transformation of the original intended appearance of the rose into its current degraded state. MA-XRPD enabled us to precisely correlate in situ formed products with what is optically visible on the surface and demonstrated that the precipitated lead arsenates and arsenolite from the yellow pigment orpiment and the light-induced fading of an organic yellow lake irreversibly changed the artist's intentional light-shadow modeling.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000811556500011	Publication Date	2022-06-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2375-2548	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	13.6	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 13.6
	Call Number	UA @ admin @ c:irua:189657			Serial	7205
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	Author	Gestels, A.; Van der Snickt, G.; Caen, J.; Nuyts, G.; Legrand, S.; Vanmeert, F.; Detry, F.; Janssens, K.; Steenackers, G.
	Title	Combined MA-XRF, MA-XRPD and SEM-EDX analysis of a medieval stained-glass panel formerly from Notre Dame, Paris reveals its material history			Type	A1 Journal article
	Year	2022	Publication	Microchemical journal	Abbreviated Journal	Microchem J
	Volume	177	Issue		Pages	107304
	Keywords	A1 Journal article; Engineering sciences. Technology; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	As part of its conservation-restoration, the 13th century stained-glass panel ‘the Annunciation’, was examined at the micro- and macro level. This window, since 1898 in the collection of the Museum Mayer Van den Bergh (Antwerp, B), was formerly a part of the southern Rose window of the Notre Dame Cathedral (Paris, F). The insigths emerging from a first phase of the analysis, comprising non-invasive analysis techniques such as optical microscopy combined with macroscopic X-ray fluorescence (MA-XRF) and X-ray diffraction (MA-XRPD) mapping, were used to select sampling positions for the second phase of investigation that involved micro-invasive analysis, namely scanning-electron microscopy coupled to energy-dispersive X-ray analysis (SEM-EDX). The aim of the investigation was fourfold: (1) to assess the applicability of MA-XRF scanning for the characterisation of stained glass windows prior to any conservation or restoration procedure, (2) to assess the applicability of MA-XRPD scanning to identify the degradation products formed on the surface of stained glass windows, (3) to establish a method to limit the set of sampled glass fragments taken from a glass panel for quantititive analysis while maintaining sufficient representativeness and (4) to distinguish the original glass panes and grisaille paint from non-original glass panes that were inserted during various past interventions. Most of the panes in this window proved to consist of medieval potash glass, consistent with the 13th c. origin of the window while a limited number of panes were identified as non-original infills, with divergent glass compositional types and/or colorants. Most panes derive their color from the pot metal glass (i.e. homogenously colored) they were made of. Some of the panes that originally had a red flashed layer on their surface, completely or partially lost this layer due to weathering. Three main compositional glass families with similar color could be defined. With the exception of the yellow and orange panes, the chromophoric elements responsible for the dark(er) and light(er) blue (Co), green (Cu), purple (Mn) and red colors (Cu) were identified. Two different grisaille paints were encountered, part of which were restored during the 19th century. On the basis of this information, all missing pieces were replaced by glass panes with appropriate colors and the panel could be successfully conserved to its former glory. On the surface of several panes, typical glass degradation products such as calcite, syngenite and gypsum were identified, together with lead based degradation products such as anglesite and palmierite. In addition, the presence of hematite and melanotekite in the grisailles was observed; also the presence of Zn, uncorrelated to Cu, in the grissailes on the right side of the window became apparent.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000850000900001	Publication Date	2022-02-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0026-265x; 0026-265x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.8	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 4.8
	Call Number	UA @ admin @ c:irua:187493			Serial	7138
Permanent link to this record



	Author	De Kerf, T.; Gestels, A.; Janssens, K.; Scheunders, P.; Steenackers, G.; Vanlanduit, S.
	Title	Quantitative detection of corrosion minerals in carbon steel using shortwave infrared hyperspectral imaging			Type	A1 Journal article
	Year	2022	Publication	RSC advances	Abbreviated Journal	Rsc Adv
	Volume	12	Issue	50	Pages	32775-32783
	Keywords	A1 Journal article; Engineering sciences. Technology; Vision lab; Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	This study presents a novel method for the detection and quantification of atmospheric corrosion products on carbon steel. Using hyperspectral imaging (HSI) in the short-wave infrared range (SWIR) (900-1700 nm), we are able to identify the most common corrosion minerals such as: alpha-FeO(OH) (goethite), gamma-FeO(OH) (lepidocrocite), and gamma-Fe2O3 (maghemite). Six carbon steel samples were artificially corroded in a salt spray chamber, each sample with a different duration (between 1 h and 120 hours). These samples were analysed by scanning X-ray diffraction (XRD) and also using a SWIR HSI system. The XRD data is used as baseline data. A random forest regression algorithm is used for training on the combined XRD and HSI data set. Using the trained model, we can predict the abundance map based on the HSI images alone. Several image correlation metrics are used to assess the similarity between the original XRD images and the HSI images. The overall abundance is also calculated and compared for XRD and HSI images. The analysis results show that we are able to obtain visually similar images, with error rates ranging from 3.27 to 13.37%. This suggests that hyperspectral imaging could be a viable tool for the study of corrosion minerals.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000885554600001	Publication Date	2022-11-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2046-2069	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	3.9	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.9
	Call Number	UA @ admin @ c:irua:192085			Serial	7334
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	Author	Byrnes, I.; Rossbach, L.M.; Jaroszewicz, J.; Grolimund, D.; Sanchez, D.F.; Gomez-Gonzalez, M.A.; Nuyts, G.; Reinoso-Maset, E.; Janssens, K.; Salbu, B.; Brede, D.A.; Lind, O.C.
	Title	Synchrotron XRF and histological analyses identify damage to digestive tract of uranium NP-exposed Daphnia magna			Type	A1 Journal article
	Year	2023	Publication	Environmental science and technology	Abbreviated Journal
	Volume	57	Issue	2	Pages	1071-1079
	Keywords	A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	Micro-and nanoscopic X-ray techniques were used to investigate the relationship between uranium (U) tissue distributions and adverse effects to the digestive tract of aquatic model organism Daphnia magna following uranium nanoparticle (UNP) exposure. X-ray absorption computed tomography measure-ments of intact daphnids exposed to sublethal concentrations of UNPs or a U reference solution (URef) showed adverse morphological changes to the midgut and the hepatic ceca. Histological analyses of exposed organisms revealed a high proportion of abnormal and irregularly shaped intestinal epithelial cells. Disruption of the hepatic ceca and midgut epithelial tissues implied digestive functions and intestinal barriers were compro-mised. Synchrotron-based micro X-ray fluorescence (XRF) elemental mapping identified U co-localized with morphological changes, with substantial accumulation of U in the lumen as well as in the epithelial tissues. Utilizing high-resolution nano-XRF, 400-1000 nm sized U particulates could be identified throughout the midgut and within hepatic ceca cells, coinciding with tissue damages. The results highlight disruption of intestinal function as an important mode of action of acute U toxicity in D. magna and that midgut epithelial cells as well as the hepatic ceca are key target organs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000910915100001	Publication Date	2023-01-04
	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; 2023 IF: 6.198
	Call Number	UA @ admin @ c:irua:193478			Serial	7342
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	Author	Gonzalez, V.; Fazlic, I.; Cotte, M.; Vanmeert, F.; Gestels, A.; De Meyer, S.; Broers, F.; Hermans, J.; van Loon, A.; Janssens, K.; Noble, P.; Keune, K.
	Title	Lead(II) formate in Rembrandt's Night Watch : detection and distribution from the macro- to the micro-scale			Type	A1 Journal article
	Year	2023	Publication	Angewandte Chemie: international edition in English	Abbreviated Journal
	Volume		Issue		Pages	1-9
	Keywords	A1 Journal article; Art; Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	The Night Watch, painted in 1642 and on view in the Rijksmuseum in Amsterdam, is considered Rembrandt's most famous work. X-ray powder diffraction (XRPD) mapping at multiple length scales revealed the unusual presence of lead(II) formate, Pb(HCOO)(2), in several areas of the painting. Until now, this compound was never reported in historical oil paints. In order to get insights into this phenomenon, one possible chemical pathway was explored thanks to the preparation and micro-analysis of model oil paint media prepared by heating linseed oil and lead(II) oxide (PbO) drier as described in 17(th) century recipes. Synchrotron radiation based micro-XRPD (SR-mu-XRPD) and infrared microscopy were combined to identify and map at the micro-scale various neo-formed lead-based compounds in these model samples. Both lead(II) formate and lead(II) formate hydroxide Pb(HCOO)(OH) were detected and mapped, providing new clues regarding the reactivity of lead driers in oil matrices in historical paintings.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000920584500001	Publication Date	2023-01-02
	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	16.6	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 16.6; 2023 IF: 11.994
	Call Number	UA @ admin @ c:irua:194279			Serial	7318
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	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
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	Author	Ortega Saez, N.; Arno, R.; Marchetti, A.; Cauberghs, S.; Janssens, K.; Van der Snickt, G.; Al-Emam, E.
	Title	Towards a novel strategy for soot removal from water-soluble materials : the synergetic effect of hydrogels and cyclomethicone on gelatine emulsion-based photographs			Type	A1 Journal article
	Year	2023	Publication	Heritage science	Abbreviated Journal
	Volume	11	Issue	1	Pages	78-17
	Keywords	A1 Journal article; Engineering sciences. Technology; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	Gels are a popular cleaning method for paper conservators and a lot of research has been done concerning gel cleaning of paper objects over the last 15 years. Despite the close interconnection between the conservation fields of paper and photographic material, research on using gels for cleaning photographs is very scarce. However, gels can provide an excellent cleaning method for photographic material. Cleaning silver gelatine prints with aqueous solvents is very complex due to the hydrophilic properties and fragility of the gelatine layer which makes mechanical cleaning difficult. The properties of gels ensure better control over the flow and evaporation of the solvent, facilitating the cleaning process. This study is the first insight into the viability of using gellan gum gel and polyvinyl acetate-borax (PVAc-borax) gel to clean contaminants from the surface of silver gelatine photographs. It is based on self-made samples that were artificially aged and contaminated with soot. Water, ethanol (EtOH), and Kodak Photo-flo were studied as solvents to remove the soot from the silver gelatine-based prints. These solvents were loaded into the aforementioned gels and applied to the samples in two different methods. These gel cleaning methods were subsequently compared with traditional cleaning methods. In addition, the usage of cyclomethicone D4 as a protective mask for the gelatine layer was studied. Measuring methods used to evaluate the cleaning were visual comparison, microscopic observation, and densitometry. ATR-FTIR measurements were also conducted to investigate potential side-effects of the cleaning methods on the prints, such as unwanted chemical transformations or the presence of gel residues after the treatments. Most of the gel cleaning methods within this study proved to be inadequate, with the exception of the gellan gum gel loaded with 30% EtOH. It was used as a granulated gel applied mechanically on a print saturated with cyclomethicone (octamethylcyclotetrasiloxane D4). Cyclomethicone proved to be a very effective protective barrier for the water-sensitive gelatine layer with minimal reduction in cleaning effectiveness.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000970139500001	Publication Date	2023-04-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2050-7445	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.5	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 2.5; 2023 IF: NA
	Call Number	UA @ admin @ c:irua:196445			Serial	8945
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	Author	Hillen, M.; Sels, S.; Ribbens, B.; Verspeek, S.; Janssens, K.; Van der Snickt, G.; Steenackers, G.
	Title	Qualitative Comparison of Lock-in Thermography (LIT) and Pulse Phase Thermography (PPT) in Mid-Wave and Long-Wave Infrared for the Inspection of Paintings			Type	A1 Journal article
	Year	2023	Publication	Applied Sciences	Abbreviated Journal	Appl Sci-Basel
	Volume	13	Issue	7	Pages	1-13
	Keywords	A1 Journal article; Engineering sciences. Technology; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	When studying paintings with active infrared thermography (IRT), minimizing the temperature fluctuations and thermal shock during a measurement becomes important. Under these conditions, it might be beneficial to use lock-in thermography instead of the conventionally used pulse thermography (PT). This study compared the observations made with lock-in thermography (LIT) and pulse phase thermography (PPT) with halogen light excitation. Three distinctly different paintings were examined. The LIT measurements caused smaller temperature fluctuations and, overall, the phase images appeared to have a higher contrast and less noise. However, in the PPT phase images, the upper paint layer was less visible, an aspect which is of particular interest when trying to observe subsurface defects or the structure of the support. The influence of the spectral range of the cameras on the results was also investigated. All measurements were taken with a mid-wave infrared (MWIR) and long wave infrared (LWIR) camera. The results show that there is a significant number of direct reflection artifacts, caused by the use of the halogen light sources when using the MWIR camera. Adding a long-pass filter to the MWIR camera eliminated most of these artifacts. All results are presented in a side-by-side comparison.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000972133900001	Publication Date	2023-03-24
	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	OpenAccess
	Notes				Approved	Most recent IF: 2.7; 2023 IF: 1.679
	Call Number	UA @ admin @ c:irua:194898			Serial	7333
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	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
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	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
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	Author	Monico, L.; d'Acapito, F.; Cotte, M.; Janssens, K.; Romani, A.; Ricci, G.; Miliani, C.; Cartechini, L.
	Title	Total electron yield (TEY) detection mode Cr K-edge XANES spectroscopy as a direct method to probe the composition of the surface of darkened chrome yellow (PbCr1-xSxO4) and potassium chromate paints			Type	A1 Journal article
	Year	2023	Publication	Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms	Abbreviated Journal
	Volume	539	Issue		Pages	141-147
	Keywords	A1 Journal article; Engineering sciences. Technology; Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract	The darkening of chromate-pigments, including chrome yellows (PbCr1-xSxO4), is a surface phenomenon affecting late 19th-early 20th c. paintings, such as those by Van Gogh. Exploring analytical strategies that contribute to a deep understanding of darkening is therefore significant for the long-term conservation of unique masterpieces. Here, we examined the capabilities of Cr K-edge XANES spectroscopy collected at the same time in X-ray fluorescence yield (XFY) and total electron yield (TEY) detection modes to selectively study the surface composition of darkened oil paint mock-ups composed of chrome yellow (PbCr0.2S0.8O4) or potassium chromate. By discussing advantages and drawbacks in using XFY/TEY modes in relation to XFY & mu;-XANES analysis from sectioned samples, we aim at assessing if TEY-XANES spectroscopy: (i) is a selective surface method to determine the abundance of different Cr-species from paint fragments; (ii) can contribute to optimize the analytical strategy by limiting time consuming sample preparation procedures; (iii) can decrease the probability of radiation damage.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001041485400001	Publication Date	2023-04-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0168-583x	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	1.3	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 1.3; 2023 IF: 1.109
	Call Number	UA @ admin @ c:irua:198427			Serial	8944
Permanent link to this record



	Author	Janssens, K.
	Title	EXRS2022 : the 2022 edition of the European X-ray Spectrometry conference, held in Bruges, Belgium			Type	Editorial
	Year	2023	Publication	X-ray spectrometry	Abbreviated Journal
	Volume	52	Issue	6	Pages	276-278
	Keywords	Editorial; Antwerp X-ray Imaging and Spectroscopy (AXIS)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001043528400001	Publication Date	2023-08-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0049-8246	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	1.2	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 1.2; 2023 IF: 1.298
	Call Number	UA @ admin @ c:irua:198217			Serial	8865
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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
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001056388600001	Publication Date	2023-08-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1420-3049	ISBN		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
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	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
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	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
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	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
	Corporate Author				Thesis
	Publisher		Place of Publication		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
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	Author	Alvarez-Martin, A.; Quanico, J.; Scovacricchi, T.; Avranovich Clerici, E.; Baggerman, G.; Janssens, K.
	Title	Chemical mapping of the degradation of geranium lake in paint cross sections by MALDI-MSI			Type	A1 Journal article
	Year	2023	Publication	Analytical chemistry	Abbreviated Journal
	Volume	95	Issue	49	Pages	18215-18223
	Keywords	A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS); Ecosphere
	Abstract	Matrix assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) has become a powerful method to extract spatially resolved chemical information in complex materials. This study provides the first use of MALDI-MSI to define spatial–temporal changes in oil paints. Due to the highly heterogeneous nature of oil paints, the sample preparation had to be optimized to prevent molecules from delocalizing. Here, we present a new protocol for the layer-specific analysis of oil paint cross sections achieving a lateral resolution of 10 μm and without losing ionization efficiency due to topographic effects. The efficacy of this method was investigated in oil paint samples containing a mixture of two historic organic pigments, geranium lake and lead white, a mixture often employed in the work of painter Vincent Van Gogh. This methodology not only allows for spatial visualization of the molecules responsible for the pink hue of the paint but also helps to elucidate the chemical changes behind the discoloration of paintings with this composition. The results demonstrate that this approach provides valuable molecular compositional information about the degradation pathways of pigments in specific paint layers and their interaction with the binding medium and other paint components and with light over time. Since a spatial correlation between molecular species and the visual pattern of the discoloration pattern can be made, we expect that mass spectrometry imaging will become highly relevant in future degradation studies of many more historical pigments and paints.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001142876000001	Publication Date	2023-11-23
	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
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:201644			Serial	9007
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	Author	Janssens, K.; van Espen, P.
	Title	Implementation of an expert system for the qualitative interpretation of x-ray-fluorescence spectra			Type	A1 Journal article
	Year	1986	Publication	Analytica chimica acta	Abbreviated Journal
	Volume	184	Issue		Pages	117-132
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1986D964700010	Publication Date	2002-07-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2670	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:149782			Serial	5655
Permanent link to this record



	Author	Janssens, K.; van Espen, P.
	Title	Evaluation of energy-dispersive x-ray-spectra with the aid of expert systems			Type	A1 Journal article
	Year	1986	Publication	Analytica chimica acta	Abbreviated Journal
	Volume	191	Issue		Pages	169-180
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1986H681700015	Publication Date	2002-07-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2670	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:149780			Serial	5612
Permanent link to this record



	Author	van Espen, P.; Janssens, K.; Nobels, J.
	Title	AXIL-PC, software for the analysis of complex-x-ray spectra			Type	A1 Journal article
	Year	1986	Publication	Chemometrics and intelligent laboratory systems	Abbreviated Journal
	Volume	1	Issue	1	Pages	109-114
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1986K579000015	Publication Date	2002-07-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0169-7439	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:149781			Serial	5487
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	Author	Janssens, K.; van Espen, P.
	Title	A general-purpose interface between fortran and the low-level functions of the ibm-pc			Type	A1 Journal article
	Year	1988	Publication	Trends in analytical chemistry	Abbreviated Journal
	Volume	7	Issue	4	Pages	128-130
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1988M999800003	Publication Date	2002-07-25
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:149778			Serial	5450
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	Author	Janssens, K.; Vanborm, W.; van Espen, P.
	Title	Increased accuracy in the automated interpretation of large epma data sets by the use of an expert system			Type	A1 Journal article
	Year	1988	Publication	Journal of research of the National Bureau of Standards (1934)	Abbreviated Journal
	Volume	93	Issue	3	Pages	260-264
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1988P035100026	Publication Date	2012-07-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0091-0635	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:149777			Serial	5660
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	Author	Janssens, K.; Nobels, J.; van Espen, P.
	Title	PC-MCA : a software package for the acquisition and processing of spectral data			Type	A1 Journal article
	Year	1988	Publication	Chemometrics and intelligent laboratory systems	Abbreviated Journal
	Volume	3	Issue	4	Pages	335-341
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1988P260100012	Publication Date	2002-07-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0169-7439	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:149776			Serial	5768
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	Author	Janssens, K.; Dorrine, W.; van Espen, P.
	Title	The development process of an expert system for the automated interpretation of large epma data sets			Type	A1 Journal article
	Year	1988	Publication	Chemometrics and intelligent laboratory systems	Abbreviated Journal
	Volume	4	Issue	2	Pages	147-161
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1988Q148500007	Publication Date	2002-07-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0169-7439	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:149775			Serial	5872
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	Author	Storms, H.M.; Janssens, K.H.; Török, S.B.; Van Grieken, R.E.
	Title	Evaluation of the ArmstrongBuseck correction for automated electron probe X-ray microanalysis of particles			Type	A1 Journal article
	Year	1989	Publication	X-ray spectrometry	Abbreviated Journal
	Volume	18	Issue	2	Pages	45-52
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The ArmstrongBuseck correction for absorption effects in electron probe x-ray microanalysis of particles considers seven specific particle shapes, and for these geometries exact correction equations are used. This procedure implies that the analyst has to associate the particle to be analysed with a certain particle type; an arbitrary relative thickness is sometimes assumed. A theoretical study was made of this absorption correction as a function of the particle composition, type and thickness for micrometre-sized particles. It appears that a correct choice of the particle type is critical. However, when the analytical results are normalized to 100%, the differences between the models are much less pronounced, and it is justified to assume a spherical model in all cases.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1989U261400001	Publication Date	2005-05-28
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:116489			Serial	5616
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