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Author Moro, G.; De Wael, K.; Moretto, L.M.
Title Challenges in the electrochemical (bio)sensing of non-electroactive food and environmental contaminants Type A1 Journal article
Year 2019 Publication Current opinion in electrochemistry Abbreviated Journal
Volume 16 Issue 16 Pages 57-65
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The electrochemical detection of non-electroactive contaminants can be successfully faced via the use of indirect detection strategies. These strategies can provide sensitive and selective responses often coupled with portable and user-friendly analytical tools. Indirect detection strategies are usually based on the change in the signal of an electroactive probe, induced by the presence of the target molecule at a modified electrode. This critical review aims at addressing the developments in indirect electro-sensing strategies for non-electroactive contaminants in food and environmental analysis in the last years (2017-2019). Emphasis is given to the strategy design, the electrode modifiers used and the feasibility of technological transfer.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000485814400010 Publication Date 2019-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2451-9103; 2451-9111 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 4 Open Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:159574 Serial 5498
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Author Cotte, M.; Genty-Vincent, A.; Janssens, K.; Susini, J.
Title Applications of synchrotron X-ray nano-probes in the field of cultural heritage Type A1 Journal article
Year 2018 Publication Comptes rendus : physique Abbreviated Journal Cr Phys
Volume 19 Issue 7 Pages 575-588
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Synchrotron-based techniques are increasingly used in the field of cultural heritage, and this review focuses notably on the application of nano-beams to access high-spatial-resolution information on fragments sampled in historical or model artworks. Depending on the targeted information, various nano-analytical techniques can be applied, providing both identification and localization of the various components. More precisely, nano-X-ray fluorescence probes elements, nano-X-ray diffraction identify crystalline phases, and nano X-ray absorption spectroscopy is sensitive to speciation. Furthermore, computed tomography-based techniques can provide useful information about the morphology and in particular the porosity of materials. (C) 2018 Academie des sciences. Published by Elsevier Masson SAS.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000451631400006 Publication Date 2018-08-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1631-0705; 1878-1535 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.048 Times cited 3 Open Access
Notes ; ; Approved Most recent IF: 2.048
Call Number UA @ admin @ c:irua:156320 Serial 5476
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Author Anaf, W.; Schalm, O.; Janssens, K.; De Wael, K.
Title Understanding the (in)stability of semiconductor pigments by a thermodynamic approach Type A1 Journal article
Year 2015 Publication Dyes and pigments Abbreviated Journal Dyes Pigments
Volume 113 Issue Pages 409-415
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Several artists pigments are semiconductors. Some of these materials appear stable over time, whereas others already show remarkable signs of degradation after limited time periods. The (in)stability of these pigments can be understood using a thermodynamic approach. For several pigment-related materials, the thermodynamic oxidation and reduction potential (ϕox and ϕred) were determined and evaluated considering the absolute energy positions of the valence and conduction band edges and the water redox potentials. The positions of ϕox and ϕred can be used in a fast screening of the stability of semiconductor pigments towards photoinduced corrosion in an aqueous/humid environment. This theoretical approach corresponds well with experimental data on pigment permanence and degradation phenomena found in literature.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000346543200052 Publication Date 2014-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0143-7208 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.473 Times cited 14 Open Access
Notes ; The authors acknowledge the funding from the Belspo S2-ART project (Belgian Federal Government) SD/RI/04A. ; Approved Most recent IF: 3.473; 2015 IF: 3.966
Call Number UA @ admin @ c:irua:118875 Serial 5885
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Author Alvarez-Martin, A.; Trashin, S.; Cuykx, M.; Covaci, A.; De Wael, K.; Janssens, K.
Title Photodegradation mechanisms and kinetics of Eosin-Y in oxic and anoxic conditions Type A1 Journal article
Year 2017 Publication Dyes and pigments Abbreviated Journal Dyes Pigments
Volume 145 Issue Pages 376-384
Keywords A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract Lakes based on Eosin-Y are extensively used by 19th century artists. Unfortunately, the identification of these pigments in paintings is a difficult task because Eosin-Y degrades very fast under the influence of light. The characterization of the (photo)degradation products of Eosin-Y can be very useful for the identification of these pigments in historic works of art and related cultural heritage artifacts. Furthermore, knowledge on how different factors influence the discoloration process (e.g. different types of irradiation sources and presence/absence of oxygen) is a valuable tool for preventive conservation. To this aim we performed a study on the photodegradation of Eosin-Y in solution under different illumination and in both oxic and anoxic conditions. The photodegradation of Eosin-Y was monitored by UV-VIS spectrophotometry, LC-QTOFMS and electrochemistry techniques. Results indicated higher degradation rates, by a factor of 20 or higher, under illumination with wavelengths near to the main absorbance band of the red pigment. Two different degradation pathways are observed under the conditions studied. LC-QTOFMS and electrochemistry suggested that in the presence of oxygen the degradation mechanism is an oxidative process where the breakdown of the structure causes the total discoloration. Meanwhile under anoxic conditions, a debromination process takes place while the chromophore, and consequently the color of the molecule in solution, remains essentially intact.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000405972900046 Publication Date 2017-06-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0143-7208 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.473 Times cited 18 Open Access
Notes ; ; Approved Most recent IF: 3.473
Call Number UA @ admin @ c:irua:144385 Serial 5770
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Author Beltran, V.; Marchetti, A.; De Meyer, S.; Nuyts, G.; De Wael, K.
Title Geranium lake pigments : the role of the synthesis on the structure and composition Type A1 Journal article
Year 2021 Publication Dyes And Pigments Abbreviated Journal Dyes Pigments
Volume 189 Issue Pages 109260
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Eosin Y has an extraordinary capacity to form complexes with metallic elements, that have applications in many different fields, from photovoltaics and photocatalysis to historical artists? pigments. To unravel the complexes reactivity, it is essential to have a precise knowledge of their structure and composition, as well as how these can be affected by the synthesis protocol, an often underestimated factor. This manuscript presents a thorough investigation of the structure and composition of eosin Y complexes based on Al and Pb, by FTIR, XRPD and Raman spectroscopy, with a particular focus on the effect of the synthesis conditions. Results clearly show the change of the coordination mode in Pb complexes depending on the protocol, while the structure of Al complexes remains stable. In both cases, the formation of by-products was observed. Additionally, a detailed band assignment of the FTIR and Raman spectra of eosin Y and Pb and Al complexes is described, providing interesting details such as the interaction between the metallic ion and the xanthene moiety (chromophore). This is extremely important for the analysis of historical paintings where eosin Y is bonded to metallic ions, as well as for other materials in dye-sensitized solar cells, wastewater treatment or photocatalysis.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000634733200001 Publication Date 2021-03-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0143-7208 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.473 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.473
Call Number UA @ admin @ c:irua:177676 Serial 8002
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Author Pauwels, D.; Pilehvar, S.; Geboes, B.; Hubin, A.; De Wael, K.; Breugelmans, T.
Title A new multisine-based impedimetric aptasensing platform Type A1 Journal article
Year 2016 Publication Electrochemistry communications Abbreviated Journal Electrochem Commun
Volume 71 Issue Pages 23-27
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
Abstract In this work an aptamer-based biosensor is combined with a multisine electrochemical impedance spectroscopy sensing methodology into a novel and promising biosensing strategy. Employing a multisine instead of a traditional single sine measuring method allows the detection and quantification of parameters that provide information about the accuracy and reliability of the results, such as noise and distortions. This does not only lead to a shorter measurement time, but it also enables an easy and fast evaluation of the quality of the data and fitting, leading to more accurate results.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000383445000006 Publication Date 2016-07-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1388-2481; 1873-1902 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.396 Times cited 1 Open Access
Notes ; ; Approved Most recent IF: 4.396
Call Number UA @ admin @ c:irua:134765 Serial 5746
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Author Mendonça, C.D.; Rahemi, V.; Hereijgers, J.; Breugelmans, T.; Machado, S.A.S.; De Wael, K.
Title Integration of a photoelectrochemical cell in a flow system for quantification of 4-aminophenol with titanium dioxide Type A1 Journal article
Year 2020 Publication Electrochemistry Communications Abbreviated Journal Electrochem Commun
Volume 117 Issue Pages 106767-5
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
Abstract The photoelectrochemical quantification of phenolic compounds such as hydroquinone (HQ) and 4-aminophenol (4-AP) is accomplished by integrating a photoelectrochemical cell into a flow injection analysis (FIA) setup. It is a well-known fact that during the electroanalysis of phenolic compounds, the electrode surface is susceptible to poisoning. However, electrode fouling can be reduced significantly by using the FIA system with periodic washing of the electrode. Reactive oxygen species (ROS), which are generated on the surface of TiO2 under UV light, can oxidize phenolic compounds such as 4-AP. The oxidized form of 4-AP is reduced back at the electrode surface, generating a measurable signal proportional to its concentration. The factors influencing the perfor-mance of the sensor, such as flow rate, applied potential for back reduction and pH, are investigated in detail. In the concentration range 0.0125-1.0 mu M, a linear correlation between the photocurrent and the concentration of 4-AP was observed with a sensitivity of 0.6 A M-1 cm(-2) and a limit of detection of 18 nM. A straightforward analytical methodology for the on-site, highly sensitive and low-cost quantification of phenolic compounds is presented, based on the use of TiO2 in a photoelectrochemical flow cell.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000552618700004 Publication Date 2020-06-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1388-2481; 1873-1902 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.4 Times cited 1 Open Access
Notes ; The authors thank FAPESP funding for the fellowship to Camila D. Mendonca (Grant #2018/13724-0) and FWO funding (grant 12T4219N and 28761) for the postdoctoral fellowship to Dr. Vanoushe Rahemi and Dr. Jonas Hereijgers. ; Approved Most recent IF: 5.4; 2020 IF: 4.396
Call Number UA @ admin @ c:irua:169924 Serial 6547
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Author Lybaert, J.; Maes, B.U.W.; Tehrani, K.A.; De Wael, K.
Title The electrochemistry of tetrapropylammonium perruthenate, its role in the oxidation of primary alcohols and its potential for electrochemical recycling Type A1 Journal article
Year 2015 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 182 Issue Pages 693-698
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)
Abstract The search for strategies aiming at more sustainable (oxidation) reactions has led to the application of electrochemistry for recycling the spent catalyst. In this work, an electrochemical study of the tetrapropylammonium perruthenate catalyst (TPAP) and its activity towards a primary alcohol, n-butanol, has been carried out as well as a control study with tert-butanol. The redox chemistry of TPAP and the transition between the perruthenate anion and ruthenium tetroxide in a non-aqueous solvent have been, for the first time, investigated in depth. The oxidation reaction of n-butanol in the presence of TPAP has been electrochemically elucidated by performing potentiostatic experiments and registration of the corresponding oxidation current. Furthermore, it was shown that, by applying a specific potential, the reoxidized TPAP is able to oxidize/convert the primary alcohol, paving the way for practical applications using TPAP in electrochemical synthesis. The conversion of n-butanol into n-butanal was proven by the use of GC-MS.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000365075800084 Publication Date 2015-09-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.798 Times cited 2 Open Access
Notes ; ; Approved Most recent IF: 4.798; 2015 IF: 4.504
Call Number UA @ admin @ c:irua:127676 Serial 5599
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Author Lybaert, J.; Tehrani, K.A.; De Wael, K.
Title Mediated electrolysis of vicinal diols by neocuproine palladium catalysts Type A1 Journal article
Year 2017 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 247 Issue Pages 685-691
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)
Abstract Synthetic electrochemistry agrees well with the principles of sustainable chemistry, therefore it is considered as a more environmentally friendly approach than some current synthetic methods Here, we present a new strategy for the chemoselective oxidation of vicinal diols, viz. the integration of neocuproine palladium catalysts and electrosynthesis. Benzoquinones are used as an effective mediator as the reduced species (hydroquinones) can be easily reoxidized at relative low potentials at an electrode surface. NeocuproinePd(OAc)2 efficiently works as a catalyst in an electrolysis reaction for vicinal diols at room temperature. This is a remarkable observation given the fact that aerobic oxidation reactions of alcohols typically need a more complex catalyst, i.e. [neocuproinePdOAc]2[OTf]2. In this article we describe the optimization of the electrolysis conditions for the neocuproinePd(OAc)2 catalyst to selectively oxidize diols. The suggested approach leads to conversion of alcohols with high yields and provides an interesting alternative to perform oxidation reactions under mild conditions by the aid of electrochemistry.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000408582300072 Publication Date 2017-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.798 Times cited Open Access
Notes ; ; Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:144118 Serial 5706
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Author Pauwels, D.; Ching, H.Y.V.; Samanipour, M.; Neukermans, S.; Hereijgers, J.; Van Doorslaer, S.; De Wael, K.; Breugelmans, T.
Title Identifying intermediates in the reductive intramolecular cyclisation of allyl 2-bromobenzyl ether by an improved electron paramagnetic resonance spectroelectrochemical electrode design combined with density functional theory calculations Type A1 Journal article
Year 2018 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 271 Issue 271 Pages 10-18
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
Abstract The electrochemical activation of C-X bonds requires very negative electrode potentials. Lowering the overpotentials and increasing the catalytic activity requires intensive electrocatalytic research. A profound understanding of the reaction mechanism and the influence of the electrocatalyst allows optimal tuning of the electrocatalyst. This can be achieved by combining electrochemical techniques with electron paramagnetic resonance (EPR) spectroscopy. Although this was introduced in the mid-twentieth century, the application of this combined approach in electrocatalytic research is underexploited. Several reasons can be listed, such as the limited availability of EPR instrumentation and electrochemical devices for such in situ experiments. In this work, a simple and inexpensive construction adapted for in situ EPR electrocatalytic research is proposed. The proof of concept is provided by studying a model reaction, namely the reductive cyclisation of allyl 2-bromobenzyl ether which has interesting industrial applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430369800002 Publication Date 2018-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.798 Times cited 2 Open Access
Notes ; The authors would like to thank Melissa Van Landeghem for her assistance with the experimental work and analysis of the data. Jonas Hereijgers greatly acknowledges the Research Foundation Flanders (FWO) for support through a Post-Doctoral grant (12Q8817N). H.Y. Vincent Ching gratefully acknowledges the University of Antwerp for a Post-Doctoral grant. Sabine Van Doorslaer and Tom Breugelmans acknowledge the FWO for research funding (research grant G093317N). ; Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:150463 Serial 5652
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Author Gaetani, C.; Gheno, G.; Borroni, M.; De Wael, K.; Moretto, L.M.; Ugo, P.
Title Nanoelectrode ensemble immunosensing for the electrochemical identification of ovalbumin in works of art Type A1 Journal article
Year 2019 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 312 Issue 312 Pages 72-79
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This research is aimed to the study and application of an electrochemical immunosensor for the detection of ovalbumin (OVA) from egg white (or albumen) used as a binder in some works of art, such as some historical photographic prints and tempera paintings. The immunosensor takes advantage of the interesting biodetection capabilities offered by nanoelectrode ensembles (NEEs). The NEEs used to this aim are prepared by template deposition of gold nanoelectrodes within the pores of track-etched polycarbonate (PC) membranes. The affinity of polycarbonate for proteins is exploited to capture OVA from the aqueous extract obtained by incubation in phosphate buffer of a small sample fragment (<1 mg). The captured protein is reacted selectively with anti-OVA antibody, labelled with glucose oxidase (GOx). In the case of positive response, the addition of the GOx substrate (i.e. glucose) and a suitable redox mediator (a ferrocenyl derivative) reflects in the up rise of an electrocatalytic oxidation current, which depends on the OVA amount captured on the NEE, this amount correlating with OVA concentration in the extract. After optimization, the sensor is successfully applied to identify OVA in photographic prints dating back to the late 19th century, as well as in ancient tempera paintings from the 15th and 18th centuries.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000468595500008 Publication Date 2019-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.798 Times cited 2 Open Access
Notes ; ; Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:159573 Serial 5743
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Author Mendonça, C.D.; Khan, S.U.; Rahemi, V.; Verbruggen, S.W.; Machado, S.A.S.; De Wael, K.
Title Surface plasmon resonance-induced visible light photocatalytic TiO₂ modified with AuNPs for the quantification of hydroquinone Type A1 Journal article
Year 2021 Publication Electrochimica Acta Abbreviated Journal Electrochim Acta
Volume 389 Issue Pages 138734
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL)
Abstract The impregnation of size-controlled gold nanoparticles (AuNPs) on an anatase TiO2 structure (AuNPs@TiO2) was studied for the photoelectrochemical detection of hydroquinone (HQ) under visible light illumination integrated into a flow injection analysis (FIA) setup. The crystalline form of TiO2 was preserved during synthesis and the homogeneous distribution of AuNPs over the TiO2 structure was confirmed. Its photoelectrocatalytic activity was improved due to the presence of AuNPs, preventing charge recombination in TiO2 and improving its light absorption ability by the surface plasmon resonance effect (SPR). The FIA system was used in order to significantly reduce the electrode fouling during electroanalysis through periodic washing steps of the electrode surface. During the amperometric detection process, reactive oxygen species (ROS), generated by visible light illumination of AuNPs@TiO2, participate in the oxidation process of HQ. The reduction of the oxidized form of HQ, i.e. benzoquinone (BQ) occurs by applying a negative potential and the measurable amperometric response will be proportional to the initial HQ concentration. The influencing parameters on the response of the amperometric photocurrent such as applied potential, flow rate and pH were investigated. The linear correlation between the amperometric response and the concentration of HQ was recorded (range 0.0125 – 1.0 µM) with a limit of detection (LOD) of 33.8 nM and sensitivity of 0.22 A M−1 cm−2. In this study, we illustrated for the first time that the impregnation of AuNPs in TiO2 allows the sensitive detection of phenolic substances under green laser illumination by using a photoelectrochemical flow system.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000687283100018 Publication Date 2021-06-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.798 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:178908 Serial 8626
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Author Van Echelpoel, R.; Kranenburg, R.; van Asten, A.; De Wael, K.
Title Electrochemical detection of MDMA and 2C-B in ecstasy tablets using a selectivity enhancement strategy by in-situ derivatization Type A1 Journal article
Year 2022 Publication Forensic chemistry Abbreviated Journal
Volume 27 Issue Pages 100383
Keywords A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract Forensic drug laboratories are confronted with increasing amounts of drugs and a demand for faster results that are directly available on-site. In addition, the drug market is getting more complex with hundreds of new psychoactive substances (NPS) entering the market in recent years. Rapid and on-scene presumptive drug testing therefore faces a shift from manual colorimetric tests towards approaches that can detect a wider range of components and process results automatically. Electrochemical detection offers these desired characteristics, making it a suitable candidate for on-site drug detection. In this study, a two-step electrochemical sensor is introduced for the detection of MDMA and 2C-B. Firstly, a direct electrochemical analysis was performed to detect MDMA. Validation experiments on over 70 substances revealed that 2C-B was the only frequently encountered drug that gave a false positive result for MDMA in this first analysis. A second step using in-situ derivatization was subsequently introduced. To this end, formaldehyde was used for N-methylation of 2C-B thereby enhancing its electrochemical profile. The enriched electrochemical fingerprint in the second step allowed for clear differentiation between MDMA and 2C-B. The applicability of this approach was demonstrated with 71 ecstasy tablets seized by the Amsterdam Police. The MDMA/2C-B sensor correctly identified all 39 MDMA-containing tablets and 10 out of 11 tablets containing 2C-B. Most notably, correct results were also obtained for dark colored tablets in which both spectroscopic analysis and colorimetric tests failed due to obscured signals.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000725708200002 Publication Date 2021-11-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2468-1709 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
Call Number UA @ admin @ c:irua:183340 Serial 7149
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Author Lopes, F.; Lima, A.; Pires de Matos, A.; Custódio, J.; Cagno, S.; Schalm, O.; Janssens, K.
Title Characterization of 18th century Portuguese glass from Real Fábrica de Vidros de Coina Type A1 Journal article
Year 2017 Publication Journal of Archaeological Science: Reports Abbreviated Journal
Volume 14 Issue Pages 137-145
Keywords A1 Journal article; Engineering sciences. Technology; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract This work reports the first systematic chemical characterization of Portuguese 18th century glassware. 28 selected glass fragments, recovered from an archaeological excavation carried out in the site where King D. João V of Portugal established an important glass manufacture, Real Fábrica de Vidros de Coina (Coina Royal Glass Factory), were studied. This factory operated from 1719 until 1747, the year in which the factory was transferred to Marinha Grande. The fragments were analysed by micro-energy dispersive X-ray fluorescence (micro-EDXRF), using a portable spectrometer ArtTAX, and scanning electron microscopy (SEM-EDX). The analytical data showed that a large variety of glass types was manufactured in that factory, namely soda-lime glass, mixed-alkali glass, high lime-low alkali glass, potash glass and lead glass. In general, the composition of the glass varies according to the function of the objects. It was demonstrated that micro-EDXRF can be an important tool to characterize museum glass objects when only in situ non-invasive analytical methods are allowed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000415616700015 Publication Date 2017-05-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2352-409x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes ; This study was supported by FCT (Fundacao para a Ciencia e a Tecnologia) under the project POCI/HAR/55882/2004 and UID/EAT/00729/2013. The PhD grant SFRH/BD/ 85329/2012 by FCT to Filipa Lopes is also acknowledged. The authors are grateful to Rosario Gil and Camara Municipal do Barreiro for their help in accessing the archaeological glass collection. We would like to thank in particular Manuela Almeida Ferreira for her valuable support in this project. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:143545 Serial 5500
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Author Bottari, F.; De Wael, K.
Title Electrodeposition of gold nanoparticles on boron doped diamond electrodes for the enhanced reduction of small organic molecules Type A1 Journal article
Year 2017 Publication Journal of electroanalytical chemistry : an international journal devoted to all aspects of electrode kynetics, interfacial structure, properties of electrolytes, colloid and biological electrochemistry. Abbreviated Journal J Electroanal Chem
Volume 801 Issue Pages 521-526
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The performance of gold nanoparticles electrodeposited on boron doped diamond (BDD) electrodes was investigated in respect to the reduction of chloramphenicol (CAP), an antibiotic of the phenicols family. The chosen deposition protocol, three nucleation-growing pulses, shows a remarkable surface coverage, with an even distribution of average-sized gold particles (~ 50 nm), and it was proven capable of generating a three-fold increase in the CAP reduction current. A calibration plot for CAP detection was obtained in the micromolar range (535 μM) with good correlation coefficient (0.9959) and an improved sensitivity of 0.053 μA μM− 1 mm− 2 compared to the electrochemistry of CAP at a bare BDD electrode.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000411847500065 Publication Date 2017-08-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1572-6657 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.012 Times cited 4 Open Access
Notes ; This work was financially supported by the University of Antwerp (BOF) and the Research Foundation Flanders (FWO) (project G037415N). ; Approved Most recent IF: 3.012
Call Number UA @ admin @ c:irua:146372 Serial 5600
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Author Ortiz-Aguayo, D.; De Wael, K.; del Valle, M.
Title Voltammetric sensing using an array of modified SPCE coupled with machine learning strategies for the improved identification of opioids in presence of cutting agents Type A1 Journal article
Year 2021 Publication Journal Of Electroanalytical Chemistry Abbreviated Journal J Electroanal Chem
Volume 902 Issue Pages 115770
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract This work reports the use of modified screen-printed carbon electrodes (SPCEs) for the identification of three drugs of abuse and two habitual cutting agents, caffeine and paracetamol, combining voltammetric sensing and chemometrics. In order to achieve this goal, codeine, heroin and morphine were subjected to Square Wave Voltammetry (SWV) at pH 7, in order to elucidate their electrochemical fingerprints. The optimized SPCEs electrode array, which have a differentiated response for the three oxidizable compounds, was derived from Carbon, Prussian blue, Cobalt (II) phthalocyanine, Copper (II) oxide, Polypyrrole and Palladium nanoparticles ink-modified carbon electrodes. Finally, Principal Component Analysis (PCA) coupled with Silhouette parameter assessment was used to select the most suitable combination of sensors for identification of drugs of abuse in presence of cutting agents.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000714415500006 Publication Date 2021-10-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1572-6657; 1873-2569 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.012 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.012
Call Number UA @ admin @ c:irua:184018 Serial 8745
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Author Barich, H.; Cánovas, R.; De Wael, K.
Title Electrochemical identification of hazardous phenols and their complex mixtures in real samples using unmodified screen-printed electrodes Type A1 Journal article
Year 2022 Publication Journal of electroanalytical chemistry : an international journal devoted to all aspects of electrode kynetics, interfacial structure, properties of electrolytes, colloid and biological electrochemistry. Abbreviated Journal J Electroanal Chem
Volume 904 Issue Pages 115878
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract The electrochemical behavior of some of the most relevant endocrine-disrupting phenols using unmodified carbon screen-printed electrodes (SPEs) is described for the first time. Experiments were made to assess the electrochemical behavior of phenol (PHOH), pentachlorophenol (PCP), 4-tert octylphenol (OP) and bisphenol A (BPA) and their determination in the most favorable conditions, using voltammetric methods such as cyclic voltammetry (CV), linear sweep voltammetry (LSV) and square wave voltammetry (SWV) in Britton Robinson (BR) buffer. Further, the usefulness of the electrochemical approach was validated with real samples from a local river and was compared to commercial phenols test kit, which is commonly used for on-site screening in industrial streams and wastewaters. Finally, the approach was compared with a lab-bench standard method using real samples, i.e., high-performance liquid chromatography with a photodiode array detector (HPLC-DAD).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000741151200005 Publication Date 2021-11-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1572-6657; 1873-2569 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.5 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.5
Call Number UA @ admin @ c:irua:184384 Serial 7150
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Author Cagno, S.; Lind, O.C.; Popic, J.M.; Skipperud, L.; De Nolf, W.; Nuyts, G.; Vanmeert, F.; Jaroszewicz, J.; Janssens, K.; Salbu, B.
Title Micro-analytical characterization of thorium-rich aggregates from Norwegian NORM sites (Fen Complex, Telemark) Type A1 Journal article
Year 2020 Publication Journal Of Environmental Radioactivity Abbreviated Journal J Environ Radioactiv
Volume 219 Issue Pages 106273
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this study we performed microscopic characterization of mineral particles that were collected in the thorium-rich Fen Complex in Norway and identified and isolated based on autoradiography in function of their radioactivity. For this we combined information obtained with X-ray absorption mu-CT, mu-XRF and mu-XRD, both in bi- and in three-dimensional (tomographic) mode. We demonstrate that radionuclides and metals are heterogeneously distributed both within soil samples and within individual Th-enriched aggregates, which are characterised as low-density mineral bulk particles with high density material inclusions, where Th as well as several metals are highly concentrated. For these sites, it is important to take into account how these inhomogeneous distributions could affect the overall environmental behaviour of Th and progeny upon weathering due to human or environmental factors. Moreover, the estimated size of the Th-containing inclusions as determined in this work represents information of importance for the characterization of radionuclides and toxic metals exposure, as well as for assessing the viability of mining for Th and rare-earth metals in the Fen Complex and the associated environmental impact.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000535130500005 Publication Date 2020-04-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0265-931x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.3 Times cited Open Access
Notes Approved Most recent IF: 2.3; 2020 IF: 2.31
Call Number UA @ admin @ c:irua:181195 Serial 8229
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Author Patiño, Y.; Pilehvar, S.; Díaz, E.; Ordóñez, S.; De Wael, K.
Title Electrochemical reduction of nalidixic acid at glassy carbon electrodemodified with multi-walled carbon nanotubes Type A1 Journal article
Year 2017 Publication Journal of hazardous materials Abbreviated Journal J Hazard Mater
Volume 323 Issue B Pages 621-631
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The aqueous phase electrochemical degradation of nalidixic acid (NAL) is studied in this work, using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) as instrumental techniques. The promotional effect of multi-walled carbon nanotubes (MWCNT) on the the performance of glassy carbon electrodes is demonstrated, being observed that these materials catalyze the NAL reduction. The effect of surface functional groups on MWCNT −MWCNT-COOH and MWCNT-NH2was also studied. The modification of glassy carbon electrode (GCE) with MWCNT leads to an improved performance for NAL reduction following the order of MWCNT > MWCNT-NH2 > MWCNT-COOH. The best behavior at MWCNT-GCE is mainly due to both the increased electrode active area and the enhanced MWCNT adsorption properties. The NAL degradation was carried out under optimal conditions (pH = 5.0, deposition time = 20 s and volume of MWCNT = 10 μL) using MWCNT-GCE obtaining an irreversible reduction of NAL to less toxic products. Paramaters as the number of DPV cycles and the volume/area (V/A) ratio were optimized for maximize pollutant degradation. It was observed that after 15 DPV scans and V/A = 8, a complete reduction was obtained, obtaining two sub-products identified by liquid chromatography-mass spectrometry (LCMS).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000390513700004 Publication Date 2016-10-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3894 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.065 Times cited 4 Open Access
Notes ; This work was supported by the Spanish Government (contract CTQ2011-29272-C04-02) and by the Government of the Principality of Asturias (contract FC-15-GRUPIN14-078). Y. Patifio thanks the Government of the Principality of Asturias for a Ph.D. fellowship (Severo Ochoa Program). S.P. and K.D.W. are thankful to UA for DOCPRO financial support. ; Approved Most recent IF: 6.065
Call Number UA @ admin @ c:irua:136108 Serial 5594
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Author Schalm, O.; Nuyts, G.; Janssens, K.
Title Some critical observations about the degradation of glass : the formation of lamellae explained Type A1 Journal article
Year 2021 Publication Journal Of Non-Crystalline Solids Abbreviated Journal J Non-Cryst Solids
Volume 569 Issue Pages 120984
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This study demonstrates that the mechanism responsible for the transformation of glass into a degradation layer is pH-dependent. In acid conditions, the transformed glass is homogeneous and brittle. In mild alkaline conditions, transformed glass is heterogeneous due to the presence of lamellae composed of silica nanoparticles and the occurrence of Ca-rich inclusions. The fundamental difference between acid and alkaline conditions cannot be explained by the currently accepted degradation mechanism based on ion exchange. To explain this critical observation, we propose a refined degradation mechanism based on existing knowledge that involves several inwardly moving reaction fronts. The fronts responsible for the transformation of the silicate network into amorphous silica are also responsible for the morphology of the transformed glass. We have identified the feedback mechanism that explains the formation of lamellae in alkaline conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000674487200009 Publication Date 2021-06-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3093 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.124 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 2.124
Call Number UA @ admin @ c:irua:179835 Serial 8551
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Author Buczyńska, A.J.; Geypens, B.; Van Grieken, R.; De Wael, K.
Title Optimization of sample clean-up for the GC-C-IRMS and GC-IT-MS analysis of PAHs from air particulate matter Type A1 Journal article
Year 2015 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 119 Issue Pages 83-92
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The optimization of sample clean-up for the analysis of air particulate matter PAHs stable carbon isotope ratio using Solid Phase Extraction (SPE) cartridges is described in this paper. Various adsorbents, such as silica gel, alumina, florisil, commercially available for sample purification were compared. Best performance for the clean-up of 24-h air particulate matter samples was obtained with activated silica-gel columns in terms of selectivity and reproducibility. One step clean-up was optimized for concentration determination and in case of co-elutions, a second step was additionally used for carbon isotope ratio analysis. The method was subsequently validated with standard reference material and was checked for carbon isotope fractionation artefacts. No significant differences in δ13C values were found for unprocessed solutions of PAHs and solution subjected to the extraction and purification procedure. The procedure was tested on air particulate matter samples collected in three different locations in Belgium. Statistically significant differences in carbon isotope ratio of PAHs between Borgerhout location and Zelzate or Gent were noticed, confirming the differences in distribution and diagnostic ratios found during the concentration analyses and different PAH sources in these locations. The results, therefore, seem very promising for the use of δ13C of PAHs as an additional information helpful in source identification of these pollutants
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000348957800013 Publication Date 2014-11-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 7 Open Access
Notes ; ; Approved Most recent IF: 3.034; 2015 IF: 2.746
Call Number UA @ admin @ c:irua:120641 Serial 5759
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Author Monico, L.; Janssens, K.; Cotte, M.; Sorace, L.; Vanmeert, F.; Brunetti, B.G.; Miliani, C.
Title Chromium speciation methods and infrared spectroscopy for studying the chemical reactivity of lead chromate-based pigments in oil medium Type A1 Journal article
Year 2016 Publication Microchemical journal T2 – TECHNART Conference, APR 27-30, 2015, Catania, ITALY Abbreviated Journal Microchem J
Volume 124 Issue Pages 272-282
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Environmental factors, such as light, humidity and temperature are triggering agents for the alteration of organic and/or inorganic constituents of oil paintings. The oxidation of the organic material is favored by increasing of relative humidity and temperature, whereas processes involving changes of the oxidation states of a number of inorganic pigments (e.g., vermilion, cadmium yellows, zinc yellows, chrome yellows) are mainly activated by light-exposure. In view of the optimization of the long-term conservation and restoration strategies of paintings it is of relevant interest to establish the consequences of thermal parameters (temperature and relative humidity) on the chemical/photochemical-reactivity and the nature of the alteration products of light sensitive-pigments in oil medium. To this aim here we propose a multi-method analytical approach based on the combination of diffuse reflectance UV-Vis, FTIR, synchrotron radiation (SR)-based micro X-ray fluorescence (mu-XRF)/micro-X-ray absorption neat edge structure ()CANES) and electron paramagnetic resonance (EPR) spectroscopies for studying the effects of different relative humidity conditions before and after light exposure on the reactivity of a series of lead chromate-based pigments [such as PbCrO4 center dot PbO (monoclinic), PbCrO4 (monoclinic) and PbCr0.2S0.8O4 (orthorhombic)] in an oil medium. The investigation of paint models was also compared to that of a late 19th century historical orthorhombic PbCr0.4S0.6O4 oil paint. Diffuse reflectance UV-Vis and FTIR spectroscopies were used to obtain information associated with chromatic changes and the formation of organo-metal degradation products at the paint surface. SR-based Cr K-edge mu-XANES/mu-XRF mapping analysis and EPR spectroscopy were employed in a complementary fashion to determine the amount, nature and distribution of Cr(III) and Cr(V)-based alteration compounds within the paints with micrometric spatial resolution. Under the employed thermal aging conditions, lead(II)-carboxylates and reduced Cr-compounds (in abundance of up to about 35% at the surface) have been identified in the lead chromate-based paints. The tendency of chromates to become reduced increased with increasing moisture levels and was favored for the orthorhombic PbCr0.2S0.8O4 compounds. The redox process gave rise to the formation of Cr(V)-species in relative amount much higher than that was formed in the equivalent paint which was exposed only to light. After light-exposure of the thermally aged paints, compounds ascribable to the oxidation of the organic binder were detected for all the types of pigments. Nevertheless, the previous thermal treatment increased the tendency toward photo-reduction of only the PbCr0.2S0.8O4 pigment. For this light-sensitive compound, the thickness variation of the reduced Cr-rich (ca. 70%) photo-alteration layer with moisture levels could be ascribed to a surface passivation phenomenon that had already occurred before photochemical aging. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000367755600042 Publication Date 2015-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 23 Open Access
Notes ; ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:131099 Serial 5519
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Author Legrand, S.; Ricciardi, P.; Nodari, L.; Janssens, K.
Title Non-invasive analysis of a 15th century illuminated manuscript fragment: point-based vs imaging spectroscopy Type A1 Journal article
Year 2018 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 138 Issue 138 Pages 162-172
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Illuminated manuscript fragments are some of the best preserved objects of Western cultural heritage. Therefore, scholars are limited to non-invasive – often point-based – methods, to answer questions on material usage, technique, origin and previous treatments. These powerful methods yield specific information; however, the information is limited to the number of points analyzed. Imaging spectroscopies such as MA-XRF and MA-rFTIR combine specificity with the power of imaging, resulting in distribution images that are interpretable by non-spectroscopists and the public at large. In this paper the possible added value of using imaging spectroscopy is discussed. Do these methods yield the same results as an extensive point-based spectroscopic campaign and can they bring novel information? As a case study, a 15th century illuminated manuscript fragment is employed in order to explore the differences between these approaches and present an inventory of their advantages and limitations. (C) 2018 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000428103000019 Publication Date 2018-01-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 12 Open Access
Notes ; The authors wish to thank Dr. Stella Panayotova, Keeper of Manuscripts and Printed Books at the Fitzwilliam Museum, for allowing technical analysis of the manuscript fragment, and Dr. Suzanne Reynolds, Assistant Keeper of Manuscripts and Printed Books, for crucial help in identifying the text on the reverse of the fragment and its significance. We also wish to thank Prof. Andrew Beeby and Dr. Catherine Nicholson for their complementary Raman analyses. The warm hospitality of the Hamilton Kerr Institute is also gratefully acknowledged. The Esmee Fairbairn Collections Fund and Cambridge University's Returning Carers Scheme provided funding for part of this research. SL and KJ acknowledge support from project METOX (contract BR/165/A6/MetOx), BELSPO, Brussels. ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:151563 Serial 5749
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Author Vermeulen, M.; Janssens, K.; Sanyova, J.; Rahemi, V.; McGlinchey, C.; De Wael, K.
Title Assessing the stability of arsenic sulfide pigments and influence of the binding media on their degradation by means of spectroscopic and electrochemical techniques Type A1 Journal article
Year 2018 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 138 Issue 138 Pages 82-91
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this paper, we used the semiconducting and lightfastness properties of synthetic and mineral arsenic sulfide pigments to study their stability by means of electrochemical and microfadometric techniques. A combination of these techniques shows that in the early stage of the degradation process, amorphous arsenic sulfides are more stable than both crystalline forms, while upon longer exposure time, amorphous pigments will fade more than both mineral pigments, making it less suitable. While the stability study was carried out on unbound pigments, the influence of the organic binder on the relative degradation of the arsenic sulfide pigments was investigated through a multi-analytical approach on pigment/binder mock-up paint samples. For this purpose, the formation of arsenic trioxide was assessed by micro Fourier transform infrared (μ-FTIR) spectroscopy while the influence of the binder on the formation of sulfates was studied by means of synchrotron radiation X-ray near edge structure (μ-XANES). Both techniques elucidate a higher stability of all pigments in gum arabic while the use of egg yolk as binder leads to the most degradation, most likely due to its sulfur-rich composition. In the context of the degradation of arsenic sulfide pigments, other binders such as animal glue, egg white or linseed oil show an intermediate impact.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000428103000010 Publication Date 2018-01-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 4 Open Access
Notes ; This research is made possible with the support of the Belgian Science Policy Office (BELSPO, Brussels) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (grant number SD/RI/04A). We gratefully acknowledge Megane Willems (Institut Paul-Lambin) for her help with mu-FFIR analyses and realization of the mock-up paint samples. We acknowledge the Paul Scherrer Institut, Villigen, Switzerland for provision of synchrotron radiation beamtime at beamline Phoenix of the SLS. ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:150149 Serial 5482
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Author van der Snickt, G.; Legrand, S.; Slama, I.; Van Zuien, E.; Gruber, G.; Van der Stighelen, K.; Klaassen, L.; Oberthaler, E.; Janssens, K.
Title In situ macro X-ray fluorescence (MA-XRF) scanning as a non-invasive tool to probe for subsurface modifications in paintings by PP Rubens Type A1 Journal article
Year 2018 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 138 Issue 138 Pages 238-245
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Within the last decade, the established synchrotron- and laboratory-based micro-XRF scanning technology inspired the development of mobile instruments that allow performing in situ experiments on paintings on a macro scale. Since the development of the first mobile scanner at the start of this decade, this chemical imaging technique has brought new insights with respect to several iconic paintings, especially in cases when standard imaging techniques such as X-Ray Radiography (XRR) or Infrared Refiectography (IRR) yielded ambiguous results. The ability of scanning MA-XRF to visualise the distribution of elements detected at and below the paint surface renders this spectrometric method particularly helpful for studying painting techniques and revealing materials that remain hidden below the paint surface. The latter aspect is especially relevant for the technical study of works by Pieter Paul Rubens (1577-1640) as this highly productive seventeenth century master is particularly renowned for the continuous application of modifications during (and even after) the entire course of the creative process. In this work, the added value of MA-XRF scanning experiments for visualising these subsurface features is exemplified by interpreting the chemical images obtained on three of Rubens' key works. Special attention is given to three types of adjustments that are particularly relevant for the technical study of Rubens' oeuvre: (1) compositional changes ('pentimenti'), exemplified by results obtained on The Portrait of Helene Fourment (ca. 1638), (2) extensions to the support ('Anstlickungen.), illustrated by imaging experiments performed on the Venus Frigida (1614) and (3) Rubens' intriguing halos around flesh tones, as found amongst others in The Incredulity of Saint Thomas (1613). The ensuing insights in the paint stratigraphy and the underlying supporting structure illustrate the potential of MA-XRF scanning for the non-invasive, comparative study of Rubens' oeuvre. The results do not only augment the understanding of the complex genesis of Rubens' works of art and his efficient painting technique, but prove valuable during conservation treatments as well, as addressed in this paper. (C) 2018 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000428103000027 Publication Date 2018-01-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 5 Open Access
Notes ; ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:151564 Serial 5657
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Author Alvarez-Martin, A.; Janssens, K.
Title Protecting and stimulating effect on the degradation of eosin lakes. Part 1 : lead white and cobalt blue Type A1 Journal article
Year 2018 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 141 Issue 141 Pages 51-63
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract An important problem encountered during the preservation of paintings and other artworks is the fading of the original colors due to exposure of the colorants to light. This fact is clearly evidenced in some of Vincent Van Gogh's paintings in which an organic red, eosin or geranium lake, is present. The identification of eosin and the characterization of its degradation products in paintings represents a challenge because of (i) the generally low concentration of the pigment remaining after an aging period of ca 100 years, (ii) the scarcity of the paint micro samples available for analysis and the difficulty of obtaining additional ones and (iii) the complexity of the degradation behavior of eosin when it is mixed with organic or inorganic pigments, binding media or varnish. This study presents an accelerated aging experiment of eosin paint models in order to understand better the discoloration process; more specifically the influence of different metals with which eosin forms complexes and of the presence of admixture pigments such as lead white and cobalt blue on the lightfastness of eosin is evaluated. Paint model samples were prepared using eosin, lead white, and cobalt blue in different mixing ratios and were characterized with several techniques before and after aging. The possible formation of intermediate molecular forms during the aging experiment and the influence of pigment ratios on the discoloration process were monitored at periodic intervals using a combination of LTV Visible and attenuated total Reflectance-Fourier transform infrared (ATR-FTIR) spectroscopies. Raman spectroscopy, scanning electron microscopy coupled to energy-dispersive X-ray analysis (SEM-EDX) and optical microscopy (OM) analyses were performed to gain information about the discoloration processes taking place within the paint models. Eosin precipitated on lead, aluminum and potassium/aluminum salts was used. These three lakes showed similar discoloration rates under light exposure. In contrast, the presence and relative abundance of the admixture pigments lead white and cobalt blue had a significant influence on the (speed of the) eosin discoloration process. The presence of lead white and cobalt blue appears to stimulate the eosin degradation. However, the cobalt blue shows less influence in the discoloration process, showing a protective effect during the first stages of the aging. This may be qualitatively explained in terms of the ability of lead white to scatter light towards eosin molecules and the absorption characteristics of cobalt blue in the green range of the electromagnetic spectrum, shielding eosin from incoming light. The color changes observed in the paint reconstructions are similar to discoloration phenomena visible in some Van Gogh paintings and can offer an explanation of the gradual discoloration process that took place over the years. These insights will be helpful to estimate the original hues color used/intended by the artist.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000439678200006 Publication Date 2018-05-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 3 Open Access
Notes ; The authors sincerely acknowledged Dr. Costanza Miliani for sharing information about the synthesis of geranium lake. The authors also acknowledged Dr. Geert van der Snickt and Gert Nuyts for the help with the aging experiments and for carrying out the SEM-EDX measurements respectively. The authors would like to acknowledge the SolarPaint project (GOA programme, Antwerp University Research Council) for financial support. ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:153087 Serial 5788
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Author Moiseeva, E.O.; Trashin, S.; Korostei, Y.S.; Khan, S.U.; Kosov, A.D.; De Wael, K.; Dubinina, T.V.; Tomilova, L.G.
Title Electrochemical and spectroelectrochemical studies of tert-butyl-substituted aluminum phthalocyanine Type A1 Journal article
Year 2021 Publication Polyhedron Abbreviated Journal Polyhedron
Volume 200 Issue Pages 115136
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Tetra-tert-butylphthalocyanine aluminum (III) chloride was studied by voltammetric and potential-resolved spectroelectrochemical methods in a non-coordinating solvent o-dichlorobenzene. Five redox transitions were found including two oxidation waves at 0.18 and 0.90 V and three reduction waves at −1.28, −1.65, and −2.63 V vs. Fc+/Fc. Electrochemical reversibility of the first oxidation and reduction processes was assessed by using the diagnostic criteria of cyclic voltammetry. First comprehensive spectroelectrochemical characterization of oxidation of the aluminum phthalocyanine is reported. Moreover, potential-resolved spectroelectrochemical titration revealed strong influence of aggregation on the UV–vis spectra and the half-wave potentials of the first oxidation transition and disclosed the presence of the partially oxidized complex in the initial solution, which noticeably affected the spectrum of the neutral form.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000640386000006 Publication Date 2021-03-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0277-5387 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.926 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 1.926
Call Number UA @ admin @ c:irua:176389 Serial 7860
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Author Nuyts, G.; Cagno, S.; Hellemans, K.; Veronesi, G.; Cotte, M.; Janssens, K.
Title Study of the early stages of Mn intrusion in corroded glass by means of combined SR FTIR/\muXRF imaging and XANES spectroscopy Type P1 Proceeding
Year 2013 Publication Procedia Chemistry T2 – Youth in Conservation of Cultural Heritage Conference (YOCOCU), June 18-20, 2012, University of Antwerp, Antwerp, Belgium Abbreviated Journal
Volume Issue Pages 239-247
Keywords P1 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Historical glass, especially medieval glass, can undergo weathering under the influence of time and environmental conditions. The aim of this investigation was to better understand the processes involved in this natural degradation process by studying artificially altered glass samples prepared for the use of evaluation of conservation methods. Non-durable glass sensors produced by the Fraunhofer Institute (type M1.0) were used as a starting material for artificial alteration. These were immersed in acidic (pH = 0, 2, 4) and neutral solutions (1 h – 8 h). In a second stage the glass samples were immersed in a 0.5 M MnCl2 solution (24 h, 48 h and 72 h), allowing intrusion of Mn from the solution into the gel layer. The samples were characterized at different stages with reflectance FTIR spectroscopy, mu XRF mapping and mu XANES. All measurements were carried out at ESRF, beamline ID21. Reflectance FTIR spectroscopy measurements were performed in the 800 4000 cm(-1) range. Cluster analysis of the resulting maps evidenced the rapid growth of the gel layer in strong acidic conditions. The average spectra for each cluster feature show for the original glass a strong Si-O- stretching band between 900 and 1000 cm(-1), whereas the gel layer could be identified by the increasing Si-O-Si bands around 1100 and 1250 cm(-1). mu XRF maps were recorded at different stages of the experiment at energies around the Mn-K edge (6.539 keV) and with a step size of 2 by 2 m. These confirm the leaching of K+ and Ca+2 from the glass and the intrusion of Mn from the solution. Mn was found throughout the entire gel layer, but with a concentration gradient peaking at the surface. XANES point measurements were recorded at various points where Mn was present. No spatial variation was found, but linear combination fitting of the spectra with various Mn reference compounds indicated that Mn2+Mn23+O4 is the main Mn compound in the gel layer, as was hypothesised by Watkinson et al. The standard corroded glass samples studied here can be used for the evaluation of conservation treatments in follow-up experiments. (C) 2013 The Authors. Published by Elsevier B.V. Selection and peer-review under responsibility of the IA-CS (Italian Association of Conservation Scientists) and University of Antwerp
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000321673900030 Publication Date 2013-04-17
Series Editor Series Title Abbreviated Series Title
Series Volume 8 Series Issue Edition
ISSN 1876-6196 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 4 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA XANES “meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. We gratefully acknowledge ESRF for granting beamtime (experiment EC873). ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:109871 Serial 5851
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Author Anaf, W.; Bencs, L.; Van Grieken, R.; Janssens, K.; De Wael, K.
Title Indoor particulate matter in four Belgian heritage sites : case studies on the deposition of dark-colored and hygroscopic particles Type A1 Journal article
Year 2015 Publication The science of the total environment Abbreviated Journal Sci Total Environ
Volume 506 Issue Pages 361-368
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Atmospheric total suspended particulate (TSP) was passively sampled by means of deployed horizontal and vertical filters in various rooms of four Belgian cultural heritage buildings, installed with various heating/ventilation systems. Soiling/blackening and deposition of inorganic, water-soluble aerosol components were considered. The extent of soiling was determined by means of two independent methods: (1) in terms of the covering rate of the samplers by optical reflection microscopy and (2) the reduction in lightness of the samplers using the CIE L*a*b* color space by spectrophotometry. A fairly good correlation was found between both methods. The inorganic composition of the deposited water-soluble TSP was quantified by means of ion chromatography. Compared to controlled environments, uncontrolled environments showed increased water-soluble aerosol content of the total deposited mass. Higher chloride deposition was observed on horizontal surfaces, compared to vertical surfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000347576800039 Publication Date 2014-11-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.9 Times cited 12 Open Access
Notes ; ; Approved Most recent IF: 4.9; 2015 IF: 4.099
Call Number UA @ admin @ c:irua:120640 Serial 5662
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Author Castanheiro, A.; Samson, R.; De Wael, K.
Title Magnetic- and particle-based techniques to investigate metal deposition on urban green Type A1 Journal article
Year 2016 Publication The science of the total environment Abbreviated Journal Sci Total Environ
Volume 571 Issue Pages 594-602
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Urban green works as a recorder of atmospheric PM. This paper reports on the utility of combining magnetic- and particle-based techniques to investigate PM leaf deposition as a bio-indicator of metal pollution. Ivy (Hedera helix) leaves were collected from five different land use classes, i.e. forest, rural, roadside, industrial, train. Leaf magnetic measurements were done in terms of saturation isothermal remanent magnetization (leaf SIRM), while ca. 40,000 leaf-deposited particles were analyzed through SEM/EDX to estimate the elemental composition. The influence of the different land use classes was registered both magnetically and in terms of metal content. Leaf area-normalized SIRM values ranged from 19.9 to 444.0 μA, in the following order forest < rural < roadside < industrial < train. Leaf SIRM showed to be significantly correlated (p < 0.01) with the content in Fe, Zn, and Pb, followed by Mn and Cd (p < 0.05), while no significant correlation was found with the metals Cr and Cu. Although presenting a similar metal content, roadside and train were magnetically very distinct. By exhibiting a very high content in Pb, and with an Fe content being comparable to the one observed at the forest and rural land uses, the industrial leaf-deposited particles showed to be mainly due to industrial activity. While SEM/EDX is a suitable approach for detailed particle analysis, leaf SIRM of ivy can be used as a rapid discriminatory tool for metal pollution. Their complementary use delivers further knowledge on land use classes reflecting different PM conditions and/or sources.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000383930400059 Publication Date 2016-07-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.9 Times cited 17 Open Access
Notes ; This research was supported by a PhD grant of the Research Foundation Flanders (FWO). The authors thank W. Dorrine for his help and supervision on operating the SEM, and G. Nuyts and K Wuyts for their valuable comments on data treatment The authors also acknowledge the three anonymous reviewers for their constructive comments, which helped to improve the manuscript. ; Approved Most recent IF: 4.9
Call Number UA @ admin @ c:irua:134845 Serial 5703
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