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Author Ro, C.-U.; Oh, K.-Y.; Osán, J.; de Hoog, J.; Worobiec, A.; Van Grieken, R.
Title Heterogeneity assessment in individual CaCO3-CaSO4 particles using ultrathin window electron probe X-ray microanalysis Type A1 Journal article
Year 2001 Publication Analytical chemistry Abbreviated Journal
Volume 73 Issue (up) 19 Pages 4574-4583
Keywords A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000171356800012 Publication Date 2002-07-26
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:36085 Serial 8028
Permanent link to this record
 
 
Author Bings, N.H.; Bogaerts, A.; Broekaert, J.A.C.
Title Atomic spectroscopy Type A1 Journal article
Year 2013 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 85 Issue (up) 2 Pages 670-704
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000313668400013 Publication Date 2012-11-07
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 29 Open Access
Notes Approved Most recent IF: 6.32; 2013 IF: 5.825
Call Number UA @ lucian @ c:irua:104719 Serial 190
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Author Monico, L.; Janssens, K.; Miliani, C.; Brunetti, B.G.; Vagnini, M.; Vanmeert, F.; Falkenberg, G.; Abakumov, A.; Lu, Y.; Tian, H.; Verbeeck, J.; Radepont, M.; Cotte, M.; Hendriks, E.; Geldof, M.; van der Loeff, L.; Salvant, J.; Menu, M.;
Title Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 3 : synthesis, characterization, and detection of different crystal forms of the chrome yellow pigment Type A1 Journal article
Year 2013 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 85 Issue (up) 2 Pages 860-867
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The painter, Vincent van Gogh, and some of his contemporaries frequently made use of the pigment chrome yellow that is known to show a tendency toward darkening. This pigment may correspond to various chemical compounds such as PbCrO4 and PbCr1-xSxO4, that may each be present in various crystallographic forms with different tendencies toward degradation. Investigations by X-ray diffraction (XRD), mid-Fourier Transform infrared (FTIR), and Raman instruments (benchtop and portable) and synchrotron radiation-based micro-XRD and X-ray absorption near edge structure spectroscopy performed on oil-paint models, prepared with in-house synthesized PbCrO4 and PbCr1-xSxO4, permitted us to characterize the spectroscopic features of the various forms. On the basis of these results, an extended study has been carried out on historic paint tubes and on embedded paint microsamples taken from yellow-orange/pale yellow areas of 12 Van Gogh paintings, demonstrating that Van Gogh effectively made use of different chrome yellow types. This conclusion was also confirmed by in situ mid-FTIR investigations on Van Goghs Portrait of Gauguin (Van Gogh Museum, Amsterdam).
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000313668400031 Publication Date 2012-10-10
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 79 Open Access
Notes Goa; Fwo Approved Most recent IF: 6.32; 2013 IF: 5.825
Call Number UA @ lucian @ c:irua:108707UA @ admin @ c:irua:108707 Serial 631
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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 (up) 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 Vanderborght, B.M.; Van Grieken, R.E.
Title Enrichment of trace metals in water by adsorption on activated carbon Type A1 Journal article
Year 1977 Publication Analytical chemistry Abbreviated Journal
Volume 49 Issue (up) 2 Pages 311-316
Keywords A1 Journal article; 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 0003-2700; 5206-882x ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:116513 Serial 7923
Permanent link to this record
 
 
Author Monico, L.; Cotte, M.; Vanmeert, F.; Amidani, L.; Janssens, K.; Nuyts, G.; Garrevoet, J.; Falkenberg, G.; Glatzel, P.; Romani, A.; Miliani, C.
Title Damages induced by synchrotron radiation-based X-ray microanalysis in chrome yellow paints and related Cr-compounds : assessment, quantification, and mitigation strategies Type A1 Journal article
Year 2020 Publication Analytical Chemistry Abbreviated Journal Anal Chem
Volume 92 Issue (up) 20 Pages 14164-14173
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Synchrotron radiation (SR)-based X-ray methods are powerful analytical tools for several purposes. They are widely used to probe the degradation mechanisms of inorganic artists' pigments in paintings, including chrome yellows (PbCr1-xSxO4; 0 <= x <= 0.8), a class of compounds often found in Van Gogh masterpieces. However, the high intensity and brightness of SR beams raise important issues regarding the potential damage inflicted on the analyzed samples. A thorough knowledge of the SR X-ray sensitivity of each class of pigment in the painting matrix is therefore required to find analytical strategies that seek to minimize the damage for preserving the integrity of the analyzed samples and to avoid data misinterpretation. Here, we employ a combination of Cr K-edge X-ray absorption near-edge structure spectroscopy, Cr-K-beta X-ray emission spectroscopy, and X-ray diffraction to monitor and quantify the effects of SR X-rays on the stability of chrome yellows and related Cr compounds and to define mitigation strategies. We found that the SR X-ray beam exposure induces changes in the oxidation state and local coordination environment of Cr ions and leads to a loss of the compound's crystalline structure. The extent of X-ray damage depends on some intrinsic properties of the samples (chemical composition of the pigment and the presence/absence and nature of the binder). It can be minimized by optimizing the overall fluence/dose released to the samples and by working in vacuum and under cryogenic conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000584418100072 Publication Date 2020-09-21
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 7.4 Times cited Open Access
Notes Approved Most recent IF: 7.4; 2020 IF: 6.32
Call Number UA @ admin @ c:irua:174363 Serial 7754
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Author Wouters, L.C.; Van Grieken, R.E.; Linton, R.W.; Bauer, C.F.
Title Discrimination between coprecipitated and adsorbed lead on individual calcite particles using laser microprobe mass analysis Type A1 Journal article
Year 1988 Publication Analytical chemistry Abbreviated Journal
Volume 60 Issue (up) 20 Pages 2218-2220
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1988Q513900012 Publication Date 2005-03-08
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:116526 Serial 7813
Permanent link to this record
 
 
Author Martens, T.; Mihailova, D.; van Dijk, J.; Bogaerts, A.
Title Theoretical characterization of an atmospheric pressure glow discharge used for analytical spectrometry Type A1 Journal article
Year 2009 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 81 Issue (up) 21 Pages 9096-9108
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We have investigated the plasma processes in an atmospheric pressure glow discharge (APGD) in He used for analytical spectrometry by means of fluid and Monte Carlo (MC) simulations. Typical results include the potential and electric field distributions in the plasma, the density profiles of the various plasma species throughout the discharge, the mean electron energy, as well as the rates of the various collision processes in the plasma, and the relative importance of the different production and loss rates for the various species. The similarities and differences with low-pressure glow discharges are discussed. The main differences are a very small cathode dark space region and a large positive column as well as the dominant role of molecular ions. Some characteristic features of the APGD, such as the occurrence of the different spatial zones in the discharge, are illustrated, with links to experimental observations.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000276191900062 Publication Date 2009-10-08
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 15 Open Access
Notes Approved Most recent IF: 6.32; 2009 IF: 5.214
Call Number UA @ lucian @ c:irua:79554 Serial 3604
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Author Cagno, S.; Brede, D.A.; Nuyts, G.; Vanmeert, F.; Pacureanu, A.; Tucoulou, R.; Cloetens, P.; Falkenberg, G.; Janssens, K.; Salbu, B.; Lind, O.C.
Title Combined computed nanotomography and nanoscopic x-ray fluorescence imaging of cobalt nanoparticles in caenorhabditis elegans Type A1 Journal article
Year 2017 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 89 Issue (up) 21 Pages 11435-11442
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Synchrotron radiation phase-contrast computed nanotomography (nano-CT) and two-and three-dimensional (2D and 3D) nanoscopic X-ray fluorescence (nano-XRF) were used to investigate the internal distribution of engineered-cobalt nanoparticles (Co NPs) in exposed individuals of the nematode Caenorhabditis elegans. Whole-nematodes and selected tissues and organs were 3D-rendered: anatomical 3D renderings with 50 nm voxel size enabled the visualization of spherical nanoparticle aggregates. with size tip to 200 nm within intact C. elegans. A 20 X 37 nm(2) high-brilliance beam was employed to obtain XRF elemental distribution maps of entire nematodes or anatomical details such as embryos, which could be compared with the CT data, These maps showed Co NPs to be predominantly present within the intestine and the epithelium, and they were not colocalized with Zn granules found in the lysosonie-containing vesicles or Fe agglomerates in the intestine. Iterated XRF scanning of a specimen at 0 degrees and 90 degrees angles suggested that NP aggregates were translocated into tissues outside of the intestinal lumen. Virtual-slicing by means of 2D XRF tomography, combined with holotomography, indicated presumable presence of individual NP aggregates inside the uterus and within embryos.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000414887000041 Publication Date 2017-10-10
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 13 Open Access
Notes ; This study has been funded by the Norwegian Research Council through its Centre of Excellence (CoE) funding scheme (Project 223268/F50). We gratefully acknowledge ESRF and DESY for granting beamtime and Karl Andreas Jensen for performing ICPMS analysis. We thank Erica Maremonti for supplying the phase-contrast image used in Figure ^1A. ; Approved Most recent IF: 6.32
Call Number UA @ admin @ c:irua:147383 Serial 5520
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 (up) 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
Permanent link to this record
 
 
Author Adriaensen, L.; Vangaever, F.; Gijbels, R.
Title Metal-assisted secondary ion mass spectrometry: the influence of Ag and Au deposition on molecular ion yields Type A1 Journal article
Year 2004 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 76 Issue (up) 22 Pages 6777-6785
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000225076400033 Publication Date 2004-11-12
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 67 Open Access
Notes Approved Most recent IF: 6.32; 2004 IF: 5.450
Call Number UA @ lucian @ c:irua:51980 Serial 2006
Permanent link to this record
 
 
Author Gorbanev, Y.; Privat-Maldonado, A.; Bogaerts, A.
Title Analysis of Short-Lived Reactive Species in Plasma–Air–Water Systems: The Dos and the Do Nots Type A1 Journal Article
Year 2018 Publication Analytical Chemistry Abbreviated Journal Anal Chem
Volume 90 Issue (up) 22 Pages 13151-13158
Keywords A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract This Feature addresses the analysis of the reactive species generated by nonthermal atmospheric

pressure plasmas, which are widely employed in industrial and biomedical research, as well as first

clinical applications. We summarize the progress in detection of plasma-generated short-lived

reactive oxygen and nitrogen species in aqueous solutions, discuss the potential and limitations of

various analytical methods in plasma−liquid systems, and provide an outlook on the possible future

research goals in development of short-lived reactive species analysis methods for a general

nonspecialist audience.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000451246100002 Publication Date 2018-11-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 17 Open Access Not_Open_Access
Notes European Commission, 743151 ; This work was supported by the European Marie Sklodowska- Curie Individual Fellowship within Horizon2020 (“LTPAM”, Grant No. 743151). Approved Most recent IF: 6.32
Call Number PLASMANT @ plasmant @c:irua:156301 Serial 5152
Permanent link to this record
 
 
Author Bulska, E.; Wysocka, I.A.; Wierzbicka, M.H.; Proost, K.; Janssens, K.; Falkenberg, G.
Title In vivo investigation of the distribution and the local speciation of selenium in Allium cepa L. by means of microscopic X-ray absorption near-edge structure spectroscopy and confocal microscopic X-ray fluorescence analysis Type A1 Journal article
Year 2006 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 78 Issue (up) 22 Pages 7616-7624
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000242021400003 Publication Date 2006-10-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 56 Open Access
Notes Approved Most recent IF: 6.32; 2006 IF: 5.646
Call Number UA @ admin @ c:irua:60714 Serial 5659
Permanent link to this record
 
 
Author Romero-Pastor, J.; Duran, A.; Rodríguez-Navarro, A.B.; Van Grieken, R.; Cardell, C.
Title Compositional and quantitative microtextural characterization of historic paintings by micro-X-ray diffraction and Raman microscopy Type A1 Journal article
Year 2011 Publication Analytical chemistry Abbreviated Journal
Volume 83 Issue (up) 22 Pages 8420-8428
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This work shows the benefits of characterizing historic paintings via compositional and microtextural data from micro-X-ray diffraction (μ-XRD) combined with molecular information acquired with Raman microscopy (RM) along depth profiles in paint stratigraphies. The novel approach was applied to identify inorganic and organic components from paintings placed at the 14th century Islamic UniversityMadrasah Yusufiyyain Granada (Spain), the only Islamic University still standing from the time of Al-Andalus (Islamic Spain). The use of μ-XRD to obtain quantitative microtextural information of crystalline phases provided by two-dimensional diffraction patterns to recognize pigments nature and manufacture, and decay processes in complex paint cross sections, has not been reported yet. A simple Nasrid (14th century) palette made of gypsum, vermilion, and azurite mixed with glue was identified in polychromed stuccos. Here also a Christian intervention was found via the use of smalt, barite, hematite, Brunswick green and gold; oil was the binding media employed. On mural paintings and wood ceilings, more complex palettes dated to the 19th century were found, made of gypsum, anhydrite, barite, dolomite, calcite, lead white, hematite, minium, synthetic ultramarine blue, and black carbon. The identified binders were glue, egg yolk, and oil.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000296830200011 Publication Date 2011-10-10
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:92679 Serial 7715
Permanent link to this record
 
 
Author Tsuji, K.; Spolnik, Z.; Wagatsuma, K.; Van Grieken, R.E.; Vis, R.D.
Title Grazing-exit particle-induced X-ray emission analysis with extremely low background Type A1 Journal article
Year 1999 Publication Analytical chemistry Abbreviated Journal
Volume 71 Issue (up) 22 Pages 5033-5036
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000083647100004 Publication Date 2002-07-26
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:27588 Serial 8010
Permanent link to this record
 
 
Author Vincze, L.; Vekemans, B.; Brenker, F.E.; Falkenberg, G.; Rickers, K.; Somogyi, A.; Kersten, M.; Adams, F.
Title Three-dimensional trace element analysis by confocal X-ray microfluorescence imaging Type A1 Journal article
Year 2004 Publication Analytical chemistry Abbreviated Journal
Volume 76 Issue (up) 22 Pages 6786-6791
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000225076400034 Publication Date 2004-11-12
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:49817 Serial 8669
Permanent link to this record
 
 
Author van der Snickt, G.; Janssens, K.; Dik, J.; de Nolf, W.; Vanmeert, F.; Jaroszewicz, J.; Cotte, M.; Falkenberg, G.; Van der Loeff, L.
Title Combined use of synchrotron radiation based micro-X-ray fluorescence, micro-X-ray diffraction, micro-X-ray absorption near-edge, and micro-fourier transform infrared spectroscopies for revealing an alternative degradation pathway of the pigment cadmium yellow in a painting by Van Gogh Type A1 Journal article
Year 2012 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 84 Issue (up) 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
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Author Lindner, H.; Murtazin, A.; Groh, S.; Niemax, K.; Bogaerts, A.
Title Simulation and experimental studies on plasma temperature, flow velocity, and injector diameter effects for an inductively coupled plasma Type A1 Journal article
Year 2011 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 83 Issue (up) 24 Pages 9260-9266
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract An inductively coupled plasma (ICP) is analyzed by means of experiments and numerical simulation. Important plasma properties are analyzed, namely, the effective temperature inside the central channel and the mean flow velocity inside the plasma. Furthermore, the effect of torches with different injector diameters is studied by the model. The temperature inside the central channel is determined from the end-on collected line-to-background ratio in dependence of the injector gas flow rates. Within the limits of 3% deviation, the results of the simulation and the experiments are in good agreement in the range of flow rates relevant for the analysis of relatively large droplets, i.e., 50 μm. The deviation increases for higher gas flow rates but stays below 6% for all flow rates studied. The velocity of the gas inside the coil region was determined by side-on analyte emission measurements with single monodisperse droplet introduction and by the analysis of the injector gas path lines in the simulation. In the downstream region significantly higher velocities were found than in the upstream region in both the simulation and the experiment. The quantitative values show good agreement in the downstream region. In the upstream region, deviations were found in the absolute values which can be attributed to the flow conditions in that region and because the methods used for velocity determination are not fully consistent. Eddy structures are found in the simulated flow lines. These affect strongly the way taken by the path lines of the injector gas and they can explain the very long analytical signals found in the experiments at low flow rates. Simulations were performed for different injector diameters in order to find conditions where good analyte transport and optimum signals can be expected. The results clearly show the existence of a transition flow rate which marks the lower limit for effective analyte transport conditions through the plasma. A rule-of-thumb equation was extracted from the results from which the transition flow rate can be estimated for different injector diameters and different injector gas compositions.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000297946900013 Publication Date 2011-07-29
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 34 Open Access
Notes Approved Most recent IF: 6.32; 2011 IF: 5.856
Call Number UA @ lucian @ c:irua:94001 Serial 3009
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Author Hamidi-Asl, E.; Daems, D.; De Wael, K.; Van Camp, G.; Nagels, L.J.
Title Concentration related response potentiometric titrations to study the interaction of small molecules with large biomolecules Type A1 Journal article
Year 2014 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 86 Issue (up) 24 Pages 12243-12249
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In the present article, the utility of a special potentiometric titration approach for recognition and calculation of biomolecule/small molecule interactions is reported. This approach is fast, sensitive, reproducible and inexpensive in comparison to the other methods for the determination of the association constant values (Ka) and the interaction energies (ΔG). The potentiometric titration measurement is based on the use of a classical polymeric membrane indicator electrode in a solution of the small molecule ligand. The biomolecule is used as a titrant. The potential is measured versus a reference electrode and transformed to a concentration related signal over the entire concentration interval, also at low concentrations, where the mV (y-axis) versus logcanalyte (x-axis) potentiometric calibration curve is not linear. In the procedure, the Ka is calculated for the interaction of cocaine with a cocaine binding aptamer and with an anti-cocaine antibody. To study the selectivity and cross-reactivity, other oligonucleotides and aptamers are tested, as well as other small ligand molecules such as tetrakis (4-chlorophenyl)borate, metergoline, lidocaine, and bromhexine. The calculated Ka compared favorably to the value reported in the literature using SPR. The potentiometric titration approach called Concentration related Response Potentiometry, is used to study molecular interaction for 7 macromolecular target molecules and 4 small molecule ligands.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000346683900048 Publication Date 2014-11-13
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 10 Open Access
Notes ; Financial support for this work was provided by the University of Antwerp by granting L.J.N., K.D.W, G.V.C., and Ronny Blust a POC interdisciplinary research project. ; Approved Most recent IF: 6.32; 2014 IF: 5.636
Call Number UA @ admin @ c:irua:120164 Serial 5548
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Author De Jong, M.; Sleegers, N.; Florea, A.; Van Loon, J.; van Nuijs, A.L.N.; Samyn, N.; De Wael, K.
Title Unraveling the mechanisms behind the complete suppression of cocaine electrochemical signals by chlorpromazine, promethazine, procaine, and dextromethorphan Type A1 Journal article
Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 91 Issue (up) 24 Pages 15453-15460
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre; Product development
Abstract The present work investigates the challenges accompanied by the electrochemical cocaine detection in physiological conditions (pH 7) in the presence of chlorpromazine, promethazine, procaine, and dextromethorphan, frequently used cutting agents in cocaine street samples. The problem translates into the absence of the cocaine oxidation signal (signal suppression) when in a mixture with one of these compounds, leading to false negative results. Although a solution to this problem was provided through earlier experiments of our group, the mechanisms behind the suppression are now fundamentally investigated via electrochemical and liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) strategies. The latter was used to confirm the passivation of the electrodes due to their interaction with promethazine and chlorpromazine. Electron transfer mechanisms were further identified via linear sweep voltammetry. Next, adsorption experiments were performed on the graphite screen printed electrodes both with and without potential assistance in order to confirm if the suppression of the cocaine signals is due to passivation induced by the cutting agents or their oxidized products. The proposed strategies allowed us to identify the mechanisms of cocaine suppression for each cutting agent mentioned. Suppression due to procaine and dextromethorphan is caused by fouling of the electrode surface by their oxidized forms, while for chlorpromazine and promethazine the suppression of the cocaine signal is related to the strong adsorption of these (nonoxidized) cutting agents onto the graphite electrode surface. These findings provide fundamental insights in possible suppression and other interfering mechanisms using electrochemistry in general not only in the drug detection sector.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000503910600018 Publication Date 2019-11-14
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 Open Access
Notes ; The authors acknowledge financial support from IOF-SBO/POC (UAntwerp) and the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; Approved Most recent IF: 6.32
Call Number UA @ admin @ c:irua:165727 Serial 5887
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Author Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K.
Title Cephalosporin antibiotics : electrochemical fingerprints and core structure reactions investigated by LC-MSMS Type A1 Journal article
Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 91 Issue (up) 3 Pages 2035-2041
Keywords A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract Electrochemistry and exploiting electrochemical fingerprints is a potent approach to address newly emerging surveillance needs, for instance for antibiotics. However, a comprehensive insight in the electrochemical oxidation behaviour and mechanism is re-quired for this sensing strategy. To address the lack in knowledge of the voltammetric behaviour of the cephalosporins antibiotics, a selection of cephalosporin antibiotics and two main intermediates were subjected to an electrochemical study of their redox behaviour by means of pulsed voltammetric techniques and small-scale electrolysis combined with HPLC-MS/MS analyses. Sur-prisingly, the detected oxidation products did not fit the earlier suggested oxidation of the sulfur group to the corresponding sul-foxide. The influence of different side chains, both at the three and the seven position of the β-lactam core structure on the elec-trochemical fingerprint were investigated. Additional oxidation signals at lower potentials were elucidated and linked to different side chains. These signals were further exploited to allow simultaneous detection of different cephalosporins in one voltammetric sweep. These fundamental insights can become the building blocks for an new on-site screening method.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000458220300055 Publication Date 2019-01-03
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 6 Open Access
Notes ; The authors acknowledge financial support from the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; Approved Most recent IF: 6.32
Call Number UA @ admin @ c:irua:156046 Serial 5497
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Author Ayalew, E.; Janssens, K.; De Wael, K.
Title Unraveling the reactivity of minium towards bicarbonate and the role of lead oxides therein Type A1 Journal article
Year 2016 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 88 Issue (up) 3 Pages 1564-1569
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Understanding the reactivity of (semiconductor) pigments provides vital information on how to improve conservation strategies for works of art in order to avoid rapid degradation of the pigments. This study focuses on the photoactivity of minium (Pb3O4), a semiconductor pigment, that gives rise to strong discoloration phenomena upon exposure to various environmental conditions. To demonstrate its photoactivity, an electrochemical setup with minium-modified graphite electrode (C|Pb3O4) was used. It is confirmed that minium is a p-type semiconductor which is photoactive during illumination and becomes inactive in the dark. Raman measurements confirm the formation of the degradation products. The photoactivity of a semiconductor pigment is partly defined by the presence of lead oxide (PbO) impurities; these introduce new states in the original band gap. It will be experi-mentally evidenced that the presence of PbO particles in minium leads to an upward shift of the valence band that reduces the band gap. Thus, upon photoexcitation, the electron/hole separation is more easily initialized. The PbO/Pb3O4 composite electrodes demonstrate a higher reductive photocurrent compared to the photocurrent registered at pure PbO or Pb3O4 modified electrodes. Upon exposure to light with energy close to and above the band gap, electrons are excited from the valence band to the conduction band to initialize the reduction of Pb(IV) to Pb(II), resulting in the initial formation of PbO. However in the presence of bicarbonate ions, a significantly higher photoreduction current is recorded since the PbO reacts further to form hydrocerussite. Therefore the presence of bicarbonates in the environment stimulates the photodecomposition process of minium and plays an important role in the degradation process.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000369471100014 Publication Date 2015-12-31
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 9 Open Access
Notes ; The authors acknowledge Sanne Aerts from the Laboratory of Adsorption and Catalysis (LADCA) of the University of Antwerp for her help with the UV-vis-DR. Financial support from the SOLARPAINT BOF-GOA project (University of Antwerp Research Council) is acknowledged. The authors are also indebted to F. Vanmeert for performing the XRD measurements. ; Approved Most recent IF: 6.32
Call Number UA @ admin @ c:irua:129963 Serial 5888
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Author Robberecht, H.J.; Van Grieken, R.E.
Title Sub-part-per-billion determination of total dissolved selenium and selenite in environmental waters by X-ray fluorescence spectrometry Type A1 Journal article
Year 1980 Publication Analytical chemistry Abbreviated Journal
Volume 52 Issue (up) 3 Pages 449-453
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1980JG67900021 Publication Date 2005-03-08
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:116514 Serial 8613
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Author Khan, S.U.; Trashin, S.; Beltran, V.; Korostei, Y.S.; Pelmus, M.; Gorun, S.M.; Dubinina, T., V.; Verbruggen, S.W.; De Wael, K.
Title Photoelectrochemical behavior of phthalocyanine-sensitized TiO₂ in the presence of electron-shuttling mediators Type A1 Journal article
Year 2022 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 94 Issue (up) 37 Pages 12723-12731
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract Dye-sensitized TiO(2 )has found many applications for dye sensitized solar cells (DSSC), solar-to-chemical energy conversion, water/air purification systems, and (electro)chemical sensors. We report an electrochemical system for testing dye-sensitized materials that can be utilized in photoelectrochemical (PEC) sensors and energy conversion. Unlike related systems, the reported system does not require a direct electron transfer from semiconductors to electrodes. Rather, it relies on electron shuttling by redox mediators. A range of model photocatalytic materials were prepared using three different TiO2 materials (P25, P90, and PC500) and three sterically hindered phthalocyanines (Pcs) with electron-rich tert-butyl substituents (t-Bu4PcZn, t-Bu4PcAlCl, and t-Bu4PcH2). The materials were compared with previously developed TiO(2 )modified by electron-deficient, also sterically hindered fluorinated phthalocyanine F64PcZn, a singlet oxygen (O-1(2)) producer, as well as its metal-free derivative, F64PcH2. The PEC activity depended on the redox mediator, as well as the type of TiO2 and Pc. By comparing the responses of one-electron shuttles, such as K4Fe(CN)(4), and O-1(2)-reactive electron shuttles, such as phenol, it is possible to reveal the action mechanism of the supported photosensitizers, while the overall activity can be assessed using hydroquinone. t-Bu4PcAlCl showed significantly lower blank responses and higher specific responses toward chlorophenols compared to t-Bu4PcZn due to the electron-withdrawing effect of the Al3+ metal center. The combination of reactivity insights and the need for only microgram amounts of sensing materials renders the reported system advantageous for practical applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000855284300001 Publication Date 2022-09-12
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 7.4 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 7.4
Call Number UA @ admin @ c:irua:190602 Serial 7190
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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 (up) 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 (up) 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 Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K.
Title Electrochemistry of intact versus degraded cephalosporin antibiotics facilitated by LC–MS analysis Type A1 Journal article
Year 2021 Publication Analytical Chemistry Abbreviated Journal Anal Chem
Volume 93 Issue (up) 4 Pages 2394-2402
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract The electrochemical detection of cephalosporins is a promising approach for the monitoring of cephalosporin levels in process waters. However, this class of antibiotics, like penicillins, is composed of chemically active molecules and susceptible to hydrolysis and aminolysis of the four membered β-lactam ring present. In order to develop a smart monitoring strategy for cephalosporins, the influence of degradation (hydrolysis and aminolysis) on the electrochemical fingerprint has to be taken into account. Therefore, an investigation was carried out to understand the changes of the voltammetric fingerprints upon acidic and alkaline degradation. Changes in fingerprints were correlated to the degradation pathways through the combination of square wave voltammetry and liquid chromatography quadrupole time-of-flight analysis. The characteristic electrochemical signals of the β-lactam ring disappeared upon hydrolysis. Additional oxidation signals that appeared after degradation were elucidated and linked to different degradation products, and therefore, enrich the voltammetric fingerprints with information of the state of the cephalosporins. The applicability of the electrochemical monitoring system was explored by the analysis of the intact and degraded industrial process waters containing the key intermediate 7-aminodeacetoxycephalosporanic acid (7-ADCA). Clearly, the intact process samples exhibited the expected core signals of 7-ADCA and could be quantified, while the degraded samples only showed the newly formed degradation products.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000618089100063 Publication Date 2021-01-04
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 Not_Open_Access
Notes Approved Most recent IF: 6.32
Call Number UA @ admin @ c:irua:176206 Serial 7864
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Author Marguí, E.; van Meel, K.; Van Grieken, R.; Buendía, A.; Fontás, C.; Hidalgo, M.; Queralt, I.
Title Method for the determination of Pd-catalyst residues in active pharmaceutical ingredients by means of high-energy polarized-beam energy dispersive X-ray fluorescence Type A1 Journal article
Year 2009 Publication Analytical chemistry Abbreviated Journal
Volume 81 Issue (up) 4 Pages 1404-1410
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In medicinal chemistry, Pd is perhaps the most-widely utilized precious metal, as catalyst in reactions which represent key transformations toward the synthesis of new active pharmaceutical ingredients (APIs). The disadvantage of this metal-catalyzed chemistry is that expensive and toxic metal residues are invariably left bound to the desired product. Thus, stringent regulatory guidelines exist for the amount of residual Pd that a drug candidate is allowed to contain. In this work, a rapid and simple method for the determination of Pd in API samples by high-energy polarized-beam energy dispersive X-ray fluorescence spectrometry has been developed and validated according to the specification limits of current legislation (10 mg kg−1 Pd) and the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH guidelines). Sample and calibration standards preparation includes a first step of homogenization and then, in a second step, the pressing of the powdered material into pellets without any chemical treatment. The use of several synthetic calibration standards made of cellulose to simulate the API matrix appears to be an effective means to obtain reliable calibration curves with a good spread of data points over the working range. With the use of the best measuring conditions, the limit of detection (0.11 mg kg−1 Pd) as well as the limit of quantitation (0.37 mg kg−1 Pd) achieved meet rigorous requirements. The repeatability of the XRF measurement appeared to be less than 2%, while the precision of the whole method was around 7%. Trueness was evaluated by analyzing spiked API samples at the level of the specification limit and calculating the recovery factor, which was better than 95%. To study the applicability of the developed methodology for the intended purpose, three batches of the studied API were analyzed for their Pd content, and the attained results were comparable to those obtained by the daily routine method (acid digestion plus atomic spectroscopy) used in most pharmaceutical laboratories.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000263319000015 Publication Date 2009-01-22
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:74340 Serial 8220
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Author Ro, C.-U.; Osán, J.; Szalóki, I.; de Hoog, J.; Worobiec, A.; Van Grieken, R.
Title A Monte Carlo program for quantitative electron-induced x-ray analysis of individual particles Type A1 Journal article
Year 2003 Publication Analytical chemistry Abbreviated Journal
Volume 75 Issue (up) 4 Pages 851-859
Keywords A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000181073800021 Publication Date 2003-02-14
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:40613 Serial 8279
Permanent link to this record
 
 
Author Liu, Y.; Cánovas, R.; Crespo, G.A.; Cuartero, M.
Title Thin-layer potentiometry for creatinine detection in undiluted human urine using ion-exchange membranes as barriers for charged interferences Type A1 Journal article
Year 2020 Publication Analytical Chemistry Abbreviated Journal Anal Chem
Volume 92 Issue (up) 4 Pages 3315-3323
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Herein, thin-layer potentiometry combined with ion-exchange membranes as barriers for charged interferences is demonstrated for the analytical detection of creatinine (CRE) in undiluted human urine. Briefly, CRE diffuses through an anion-exchange membrane (AEM) from a sample contained in one fluidic compartment to a second reservoir, containing the enzyme CRE deiminase. There, CRE reacts with the enzyme, and the formation of ammonium is dynamically monitored by potentiometric ammonium-selective electrodes. This analytical concept is integrated into a lab-on-a-chip microfluidic cell that allows for a high sample throughput and the operation under stop-flow mode, which allows CRE to passively diffuse across the AEM. Conveniently, positively charged species (i.e., potassium, sodium, and ammonium, among others) are repelled by the AEM and never reach the ammonium-selective electrodes; thus, possible interference in the response can be avoided. As a result, the dynamic potential response of the electrodes is entirely ascribed to the stoichiometric formation of ammonium. The new CRE biosensor exhibits a Nernstian slope, within a linear range of response from 1 to 50 mM CRE concentration. As expected, the response time (15–60 min) primarily depends on the CRE diffusion across the AEM. CRE analysis in urine samples displayed excellent results, without requiring sample pretreatment (before the introduction of the sample in the microfluidic chip) and with high compatibility with development into a potential point-of-care clinical tool. In an attempt to decrease the analysis time, the presented analytical methodology for CRE detection is translated into an all-solid-state platform, in which the enzyme is immobilized on the surface of the ammonium-selective electrode and with the AEM on top. While more work is necessary in this direction, the CRE sensor appears to be promising for CRE analysis in both urine and blood.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-01-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record
Impact Factor 7.4 Times cited Open Access
Notes Approved Most recent IF: 7.4; 2020 IF: 6.32
Call Number UA @ admin @ c:irua:184380 Serial 8667
Permanent link to this record