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	Author	Rojas, C.M.; Figueroa, L.; Janssens, K.H.; Van Espen, P.E.; Adams, F.C.; Van Grieken, R.E.
	Title	The elemental composition of airborne particulate matter in the Atacama desert, Chile			Type	A1 Journal article
	Year	1990	Publication	The science of the total environment	Abbreviated Journal
	Volume	91	Issue		Pages	251-267
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Air particulate samples were collected at Chapiquiña near Arica (Chile) with a six-stage cascade impactor for about 17-day periods during a 31 month interval. Sixteen elements were determined by energy dispersive X-ray fluorescence analysis, and the elemental concentrations were subjected to principal factor analysis. The variability with time of the coarse particles was described by two factors both related to soil dispersion, whereas the fine particle variations could be explained by a third factor related to marine influence. Enrichment factors were compared with those obtained in other remote continental areas, in particular those of air particulate matter sampled at Chacaltaya, Bolivia. Results point to a negligible anthropogenic influence.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1990CM36100019	Publication Date	2003-09-12
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:116652			Serial	5602
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	Author	Morales-Yanez, F.; Trashin, S.; Hermy, M.; Sariego, I.; Polman, K.; Muyldermans, S.; De Wael, K.
	Title	Fast one-step ultrasensitive detection of toxocara canis antigens by a nanobody-based electrochemical magnetosensor			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	18	Pages	11582-11588
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Human toxocariasis (HT) is a cosmopolitan zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis. Current HT diagnostic methods do not discriminate between active and past infections. Here, we present a method to quantify Toxocara excretory/secretory antigen, aiming to identify active cases of HT. High specificity is achieved by employing nanobodies (Nbs), single domain antigen binding fragments from camelid heavy chain-only antibodies. High sensitivity is obtained by the design of an electrochemical magnetosensor with an amperometric read-out. Reliable detection of TES antigen at 10 and 30 pg/mL level was demonstrated in phosphate buffered saline and serum, respectively. Moreover, the assay showed no cross-reactivity with other nematode antigens. To our knowledge, this is the most sensitive method to quantify the TES antigen so far. It also has great potential to develop point of care diagnostic systems in other conditions where high sensitivity and specificity are required.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000487156900016	Publication Date	2019-08-20
	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	2	Open Access
	Notes	; This project was funded by the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO-Flanders, Project G.0189.13N) and BOF UAntwerp. The authors acknowledge Prof. Pierre Dorny (Institute of Tropical Medicine Antwerp) and Dr. Beatrice Nickel (Swiss Institute of Tropical Medicine) for providing the antigens needed for the cross-reactivity experiments. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:163784			Serial	5621
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	Author	Neven, L.; Thiruvottriyur Shanmugam, S.; Rahemi, V.; Trashin, S.; Sleegers, N.; Carrion, E.N.; Gorun, S.M.; De Wael, K.
	Title	Optimized photoelectrochemical detection of essential drugs bearing phenolic groups			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	15	Pages	9962-9969
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The World Health Organization (WHO) model “List of Essential Medicines” includes among indispensable medicines antibacterials and pain and migraine relievers. Monitoring their concentration in the environment, while challenging, is important in the context of antibiotic resistance as well as their production of highly toxic compounds via hydrolysis. Traditional detection methods such as high-performance liquid chromatography (HPLC) or LC combined with tandem mass spectrometry or UV-vis spectroscopy are time-consuming, have a high cost, require skilled operators and are difficult to adapt for field operations. In contrast, (electrochemical) sensors have elicited interest because of their rapid response, high selectivity, and sensitivity as well as potential for on-site detection. Previously, we reported a novel sensor system based on a type II photosensitizer, which combines the advantages of enzymatic sensors (high sensitivity) and photoelectrochemical sensors (easy baseline subtraction). Under red-light illumination, the photosensitizer produces singlet oxygen which oxidizes phenolic compounds present in the sample. The subsequent reduction of the oxidized phenolic compounds at the electrode surface gives rise to a quantifiable photocurrent and leads to the generation of a redox cycle. Herein we report the optimization in terms of pH and applied potential of the photoelectrochemical detection of the hydrolysis product of paracetamol, i.e., 4-aminophenol (4-AP), and two antibacterials, namely, cefadroxil (CFD, beta-lactam antibiotic) and doxycycline (DXC, tetracycline antibiotic). The optimized conditions resulted in a detection limit of 0.2 mu mol L-1 for DXC, but in a 10 times higher sensitivity, 20 nmol L-1, for CFD. An even higher sensitivity, 7 nmol L-1, was noted for 4-AP.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000480499200086	Publication Date	2019-06-25
	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	2	Open Access
	Notes	; FWO and UA-BOF are acknowledged for financial support. The Center for Functional Materials of Seton Hall University is thanked for support (S.M.G. and E.N.C.). Joren Van Loon is thanked for the graphical abstract. This research was supported by the medium scale research infrastructure funding Hercules funding (SEM). ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:161831			Serial	5763
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	Author	Alvarez-Martin, A.; Cleland, T.P.; Kavich, G.M.; Janssens, K.; Newsome, G.A.
	Title	Rapid evaluation of the debromination mechanism of eosin in oil paint by direct analysis in real time and direct infusion-electrospray ionization mass spectrometry			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	16	Pages	10856-10863
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Eosin is a synthetic organic colorant prone to fading under the influence of light. On the basis of the growing interest in the understanding of the discoloration mechanism of eosin-based lakes, this study compares the ability of two ultrafast and ultrasensitive mass spectrometry techniques to detect eosin derivatives in complex matrices, such as oil media without the use of conventional separation columns or additional sample preparation protocols. Direct analysis in real time mass spectrometry (DART-MS) and direct infusion electrospray ionization mass spectrometry (DI-ESI-MS) were used to characterize the degradation pathway of eosin in oil media. The analysis protocols developed in this study are applied to discern the degradation mechanism of the lake pigment eosin (comprising the molecule per se complexed to an inorganic substrate) dispersed in linseed oil to create an oil paint. The analysis of oil paints by high resolution MS without an extraction methodology that modifies the system chemistry allowed us to identify the degradation forms without causing any additional fragmentation. Both techniques revealed the primary photodegradation pathway of eosin in linseed oil, and DI-ESI-MS provided additional information on the native conformation of the lake.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000482545300069	Publication Date	2019-07-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700; 5206-882x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.32	Times cited	3	Open Access
	Notes	; The authors would like to acknowledge the SolarPaint project (GOA program, Antwerp University Research Council) and Smithsonian Institution for financial support. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:162879			Serial	5800
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	Author	Terzano, R.; Denecke, M.A.; Falkenberg, G.; Miller, B.; Paterson, D.; Janssens, K.
	Title	Recent advances in analysis of trace elements in environmental samples by X-ray based techniques (IUPAC Technical Report)			Type	A1 Journal article
	Year	2019	Publication	Pure and applied chemistry	Abbreviated Journal	Pure Appl Chem
	Volume	91	Issue	6	Pages	1029-1063
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Trace elements analysis is a fundamental challenge in environmental sciences. Scientists measure trace elements in environmental media in order to assess the quality and safety of ecosystems and to quantify the burden of anthropogenic pollution. Among the available analytical techniques, X-ray based methods are particularly powerful, as they can quantify trace elements in situ. Chemical extraction is not required, as is the case for many other analytical techniques. In the last few years, the potential for X-ray techniques to be applied in the environmental sciences has dramatically increased due to developments in laboratory instruments and synchrotron radiation facilities with improved sensitivity and spatial resolution. In this report, we summarize the principles of the X-ray based analytical techniques most frequently employed to study trace elements in environmental samples. We report on the most recent developments in laboratory and synchrotron techniques, as well as advances in instrumentation, with a special attention on X-ray sources, detectors, and optics. Lastly, we inform readers on recent applications of X-ray based analysis to different environmental matrices, such as soil, sediments, waters, wastes, living organisms, geological samples, and atmospheric particulate, and we report examples of sample preparation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000471262400011	Publication Date	2019-05-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0033-4545	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.626	Times cited	3	Open Access
	Notes	; This document was developed as a part of IUPAC, Funder Id: http://dx.doi.org/ 10.13039/100006987, Project #2016-019-2-600 “Trace elements analysis of environmental samples with X-rays: from synchrotron to lab and from lab to synchrotron” led by Roberto Terzano (Task Group Chair). Task Group Members for this project were: Melissa Anne Denecke, Gerald Falkenberg, Armin Gross, Koen Janssens, Bradley Miller, David Paterson, Ryan Tappero, Fang-Jie Zhao. Their contribution to the project is gratefully acknowledged. ;			Approved	Most recent IF: 2.626
	Call Number	UA @ admin @ c:irua:161369			Serial	5803
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	Author	Vanmeert, F.; De Keyser, N.; van Loon, A.; Klaassen, L.; Noble, P.; Janssens, K.
	Title	Transmission and reflection mode macroscopic x-ray powder diffraction imaging for the noninvasive visualization of paint degradation in still life paintings by Jan Davidsz. de Heem			Type	A1 Journal article
	Year	2019	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	91	Issue	11	Pages	7153-7161
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The use of noninvasive chemical imaging techniques is becoming more widespread for the study of cultural heritage artifacts. Recently a mobile instrument for macroscopic X-ray powder diffraction (MA-XRPD) scanning was developed, which is capable of visualizing the distribution of crystalline (pigment) phases in quasi-flat-painted artifacts. In this study, MA-XRPD is used in both transmission and reflection mode for the analysis of three 17th century still life paintings, two paintings by Jan Davidsz. de Heem (1606-1684) and one copy painting after De Heem by an unknown artist. MA-XRPD allowed to reveal and map the presence of in situ-formed alteration products. In the works examined, two rare lead arsenate minerals, schultenite (PbHAsO4) and mimetite (Pb-5(AsO4)(3)Cl), were encountered, both at and below the paint surface; they are considered to be degradation products of the pigments realgar (alpha-As4S4) and orpiment (As2S3). In transmission mode, the depletion of lead white, present in the (second) ground layer, could be seen, illustrating the intrusive nature of this degradation process. In reflection mode, several sulfate salts, palmierite (K2Pb(SO4)(2)), syngenite (K2Ca(SO4)(2)center dot H2O), and gypsum (CaSO4 center dot 2H(2)O), could be detected, in particular, at the (top) surface of the copy painting. Estimates for the information depth and sensitivity of both transmission and reflection mode MA-XRPD for various pigments have been made. The possibility of MA-XRPD to allow for noninvasive identification and visualization of alteration products is considered a significant advantage and unique feature of this method. MA-XRPD can thus provide highly relevant information for assessing the conservation state of artworks and could guide possible future restoration treatments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000470793800031	Publication Date	2019-05-10
	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	5	Open Access
	Notes	; The authors acknowledge financial support from BELSPO (Brussels) S2-ART and METOX projects, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, and the GOA Project Solarpaint (University of Antwerp Research Council). The authors thank the Rijksmuseum, the Royal Museum of Fine Arts Antwerp, and their staff for the collaborations. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:160245			Serial	5882
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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	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	de Maeyer-Worobiec, A.; Dekov, V.M.; Laane, R.W.P.M.; Van Grieken, R.
	Title	EPXMA survey of shelf sediments (Southern Bight, North Sea): a glance beyond the XRD-invisible			Type	A1 Journal article
	Year	2009	Publication	Microchemical journal	Abbreviated Journal
	Volume	91	Issue	1	Pages	21-31
	Keywords	A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Shelf sediments of the southern North Sea, were studied with a microanalytical [electron probe X-ray microanalysis (EPXMA)] and two bulk [X-ray diffraction (XRD) and X-ray fluorescence (XRF)] techniques. The investigation proved that the promptness of the microanalytical method is combined with a reasonable analytical reliability. XRD studies of such a type of sediments with monotonous mineral composition are not able to provide mineralogical information beyond the main well-crystalline minerals and the mineralogical quantitative characteristic of the sediment based on XRD estimations are incorrect. The EPXMA mineralogical interpretations are based on the statistical evaluation of a huge data set (thousands of mineral particles) and provide a rather correct quantitative determination of the main minerals. The comparative EPXMAXRF study revealed that the Al, Si, K, Ca, Fe and to some extent Ti contents estimated by EPXMA are fairly reliable. In this respect the accuracy of the EPXMA-based mineral identification of the pure silicates, pure aluminosilicates, and Al-, Ca-, Fe- and Ti-containing minerals with simple composition is very high. Mg-calcite, augite and apatite determinations are assessed to be correct. The supposed accuracy of the clay mineral determinations is slightly lower (7080%) than that of the other main minerals due to the complex and varying composition of the clays. The identification of XRD-invisible accessory minerals and quantification of their presence in the sediments is an essential advantage of the EPXMA, which makes it a useful approach in tracing the origin of the sediments, the pathways of their transport and the geochemical processes they have undergone. However, the EPXMA has several flaws, which need to be solved in the future sediment investigations: (1) calibration with natural standards is needed in order to provide a higher accuracy of the mineral determinations; (2) any EPXMA study of sediments needs to be secured with XRF examinations of selected samples since EPXMA gives only semi-quantitative information about the abundance of the elements; (3) ultra-thin window EPXMA of low-Z elements has to be used since some of them (O, C) are always present in the main sediment components: silicates, aluminosilicates, carbonates and metal oxyhydroxides; (4) the interpretations of the clay fraction have to be supported with detailed XRD investigations of selected samples, while the mineralogy of the silt and sand fractions needs to be backed up with optical microscopy studies. The information from different analytical techniques (EPXMA with XRFXRD-optical microscopy of selected samples) combined with the knowledge about the most possible minerals in a given environment, would give the most reliable results in studying mineralogical composition of shelf sediments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000262963300006	Publication Date	2008-07-14
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:71604			Serial	7933
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	Author	Godoi, R.H.M.; Aerts, K.; Harlay, J.; Kaegi, R.; Ro, C.-U.; Chou, L.; Van Grieken, R.
	Title	Organic surface coating on Coccolithophores – Emiliania huxleyi: its determination and implication in the marine carbon cycle			Type	A1 Journal article
	Year	2009	Publication	Microchemical journal	Abbreviated Journal
	Volume	91	Issue	2	Pages	266-271
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Most of the marine precipitation of CaCO3 is due to the biological activities of planktonic and benthic organisms in waters largely oversaturated with respect to calcium carbonates. This saturation state is expected to decrease as CO2 increases in seawater. A conventional view in oceanography suggests that calcium carbonates organisms are preserved in oversaturated waters and dissolve only below the lysocline. However, it has be postulated that a fraction of the CaCO3 precipitated biogenically could dissolve in oversaturated waters due to the formation of microenvironments in which respired CO2 decreases the saturation state of seawater (Ù) in the vicinity of CaCO3 crystals. In the present study, cells of the coccolithophore Emiliania huxleyi obtained from laboratory cultures and field samples collected in the Gulf of Biscay, were examined using variable-energy electron-probe microanalysis, to determine the presence and thickness of their organic coating. In addition, a new approach for transferring micrometer-sized particles from a filter onto transmission electron microscope grids using manipulators was used to investigate individual coccolithophores. The dry thickness of an organic coating over the coccolithophore surface was found to range between 280 and 350 nm. The resemblance of this coating to the carbohydrates produced and released by the cell is discussed as well as their potential for constituting a microenvironment that hosts bacteria. The properties of this organic coating and its role in the preservation/dissolution and export of biogenic carbonates in the water column are one of the major issues of carbonate geochemistry.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000264238000020	Publication Date	2009-01-02
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:73322			Serial	8346
Permanent link to this record



	Author	De Jong, M.; Florea, A.; de Vries, A.-M.; van Nuijs, A.L.N.; Covaci, A.; Van Durme, F.; Martins, J.C.; Samyn, N.; De Wael, K.
	Title	Levamisole : a common adulterant in cocaine street samples hindering electrochemical detection of cocaine			Type	A1 Journal article
	Year	2018	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	90	Issue	8	Pages	5290-5297
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
	Abstract	The present work investigates the electrochemical determination of cocaine in the presence of levamisole, one of the most common adulterants found in cocaine street samples. Levamisole misleads cocaine color tests, giving a blue color (positive test) even in the absence of cocaine. Moreover, the electrochemical detection of cocaine is also affected by the presence of levamisole, with a suppression of the oxidation signal of cocaine. When levamisole is present in the sample in ratios higher than 1:1, the cocaine signal is no longer detected, thus leading to false negative results. Mass spectrometry and nuclear magnetic resonance were used to investigate if the signal suppression is due to the formation of a complex between cocaine and levamisole in bulk solution. Strategies to eliminate this suppressing effect are further suggested in this manuscript. In a first approach, the increase of the pH of the sample solution from pH 7 to pH 12 allowed the voltammetric determination of cocaine in the presence of levamisole in a concentration range from 10 to 5000 μM at nonmodified graphite disposable electrodes with a detection limit of 5 μM. In a second approach, the graphite electrode was cathodically pretreated, resulting in the presence of oxidation peaks of both cocaine and levamisole, with a detection limit for cocaine of 3 μM over the linear range of concentrations from 10 to 2500 μM. Both these strategies have been successfully applied for the simultaneous detection of cocaine and levamisole in three street samples on unmodified graphite disposable electrodes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000430512200049	Publication Date	2018-02-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700; 5206-882x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.32	Times cited	8	Open Access
	Notes	; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by BR/314/PI/ APTADRU Project and IOF-SBO (UAntwerp). Alexander van Nuijs acknowledges the Research Foundation-Flanders (FWO) for his postdoctoral fellowship. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:149528			Serial	5693
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	Author	Vanmeert, F.; de Nolf, W.; De Meyer, S.; Dik, J.; Janssens, K.
	Title	Macroscopic X-ray powder diffraction scanning, a new method for highly selective chemical imaging of works of art : instrument optimization			Type	A1 Journal article
	Year	2018	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	90	Issue	11	Pages	6436-6444
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In the past decade macroscopic X-ray fluorescence imaging (MA-XRF) has become established as a method for the noninvasive investigation of flat painted surfaces, yielding large scale elemental maps. MA-XRF is limited by a lack of specificity, only allowing for indirect pigment identification based on the simultaneous presence of chemical elements. The high specificity of X-ray powder diffraction (XRPD) mapping is already being exploited at synchrotron facilities for investigations at the (sub)microscopic scale, but the technique has not yet been employed using lab sources. In this paper we present the development of a novel MA-XRPD/XRF instrument based on a laboratory X-ray source. Several combinations of X-ray sources and area detectors are evaluated in terms of their spatial and angular resolution and their sensitivity. The highly specific imaging capability of the combined MA-XRPD/XRF instrument is demonstrated on a 15th/16th century illuminated manuscript directly revealing the distribution of a large number of inorganic pigments, including the uncommon yellow pigment massicot (o-PbO). The case study illustrates the wealth of new mapping information that can be obtained in a noninvasive manner using the laboratory MA-XRPD/XRF instrument.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000434893200019	Publication Date	2018-04-06
	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	11	Open Access
	Notes	; The authors thank the persons involved at Incoatec GmbH, imXPAD SAS and Dectris Ltd. for loaning us some of their products over the past years. We acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” Project and GOA Project Solarpaint (University of Antwerp Research Council). Photo Copyright Geert Van der Snickt, 2008 for the photograph of the illuminated manuscript in the TOC graphic. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:151993			Serial	5701
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	Author	Vanmeert, F.; de Nolf, W.; Dik, J.; Janssens, K.
	Title	Macroscopic X-ray powder diffraction scanning : possibilities for quantitative and depth-selective parchment analysis			Type	A1 Journal article
	Year	2018	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	90	Issue	11	Pages	6445-6452
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	At or below the surface of painted works of art, valuable information is present that provides insights into an objects past, such as the artists technique and the creative process that was followed or its conservation history but also on its current state of preservation. Various noninvasive techniques have been developed over the past 2 decades that can probe this information either locally (via point analysis) or on a macroscopic scale (e.g., full-field imaging and raster scanning). Recently macroscopic X-ray powder diffraction (MA-XRPD) mapping using laboratory X-ray sources was developed. This method can visualize highly specific chemical distributions at the macroscale (dm(2)). In this work we demonstrate the synergy between the quantitative aspects of powder diffraction and the noninvasive scanning capability of MA-XRPD highlighting the potential of the method to reveal new types of information. Quantitative data derived from a 15th/16th century illuminated sheet of parchment revealed three lead white pigments with different hydrocerussite-cerussite compositions in specific pictorial elements, while quantification analysis of impurities in the blue azurite pigment revealed two distinct azurite types: one rich in barite and one in quartz. Furthermore, on the same artifact, the depth-selective possibilities of the method that stem from an exploitation of the shift of the measured diffraction peaks with respect to reference data are highlighted. The influence of different experimental parameters on the depth-selective analysis results is briefly discussed. Promising stratigraphic information could be obtained, even though the analysis is hampered by not completely understood variations in the unit cell dimensions of the crystalline pigment phases.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000434893200020	Publication Date	2018-04-06
	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 thank Incoatec GmbH for giving us the opportunity to test the I mu S Cu X-ray source. We acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, and GOA Project Solarpaint (University of Antwerp Research Council). Photo Copyright Geert Van der Snickt, 2008 for the photograph of the illuminated manuscript in the TOC graphic. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:151994			Serial	5702
Permanent link to this record



	Author	De Jong, M.; Florea, A.; Eliaerts, J.; Van Durme, F.; Samyn, N.; De Wael, K.
	Title	Tackling poor specificity of cocaine color tests by electrochemical strategies			Type	A1 Journal article
	Year	2018	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	90	Issue	11	Pages	6811-6819
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	This paper presents electrochemical strategies for the fast screening of cocaine and most common cutting agents found in seized drug samples. First, a study on the performance of Scott color tests on cocaine and a wide range of cutting agents is described. The cutting agents causing false positive or false negative results when in mixture with cocaine are identified. To overcome the lack of specificity of color tests, we further propose a fast screening strategy by means of square wave voltammetry on disposable graphite screen printed electrodes, which reveals the unique fingerprint of cocaine and cutting agents. By employing a forward and backward scan and by a dual pH strategy, we enrich the electrochemical fingerprint and enable the simultaneous detection of cocaine and cutting agents. The effectiveness of the developed strategies was tested for the detection of cocaine in seized cocaine samples and compared with the color tests. Moreover, we prove the usefulness of square wave voltammetry for predicting possible interfering agents in color tests, based on the reduction peak of cobalt thiocyanate. The developed electrochemical strategies allow for a quick screening of seized cocaine samples resulting in a selective identification of drugs and cutting agents.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000434893200066	Publication Date	2018-05-09
	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	7	Open Access
	Notes	; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by Grants BR/314 /PI/APTADRU and IOF-SBO. ;			Approved	Most recent IF: 6.32
	Call Number	UA @ admin @ c:irua:151316			Serial	5867
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	Author	Leysen, L.A.; Roekens, E.J.; Van Grieken, R.E.; De Geyter, G.
	Title	Characterization of the weathering crust of various historical buildings in Belgium			Type	A1 Journal article
	Year	1990	Publication	The science of the total environment	Abbreviated Journal
	Volume	90	Issue		Pages	117-147
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	A variety of samples, collected from different historical buildings and monuments throughout Belgium, were thoroughly studied, using several trace- and micro-analysis techniques. Thin sections of stones and mortar joints were characterized by means of electron probe X-ray microanalysis (EPXMA). The morphological appearance of the surface weathering crust and the possible presence of non-innate particles in the crust were elucidated using petrographical and electron microscopy. Quantitative characterization of the total chemical composition of the crust surface layer and underlying layer was performed by energy-dispersive X-ray fluorescence, and by ion chromatography and atomic absorption spectrometry for the leachable components. Special attention was also paid to the chemical composition of rain and air at the particular sampling sites. The element distribution in the transition zone between the weathering crust and the original stone material was found to vary greatly amongst the different samples analyzed. Detailed EPXMA measurements on pieces of the weathering crust showed remarkable differences in morphology and composition between the surface and the underlying layer, and provided information about the presence of fly-ash and soil dust particles in the crust. Except for crusts from the city of Brussels, which were all very high in sulphate, the samples appeared to contain very variable sulphate contents; very local micro-climate and environmental conditions at a particular site are more important in determining the weathering condition of the building stones than the local air pollution situation. Bulk analytical characterization further showed, in all the crust samples studied, a very small contribution of nitrogen- and chlorine-containing weathering products, in contrast to sulphur-containing weathering salts.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1990CJ43500010	Publication Date	2003-09-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0048-9697; 1879-1026	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:116650			Serial	7636
Permanent link to this record



	Author	Verbueken, A.; Van Grieken, R.
	Title	Influence on photoplate evaluation parameters in spark source mass spectrometric analysis			Type	A1 Journal article
	Year	1981	Publication	Bulletin des sociétés chimiques belges	Abbreviated Journal
	Volume	90	Issue		Pages	331-341
	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	0037-9646	ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:116626			Serial	8099
Permanent link to this record



	Author	Van Borman, W.; Wouters, L.; Van Grieken, R.; Adams, F.
	Title	Lead particles in an urban atmosphere : an individual particle approach			Type	A1 Journal article
	Year	1990	Publication	The science of the total environment	Abbreviated Journal
	Volume	90	Issue		Pages	55-66
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In air particulate matter, sampled at a suburban site near the city of Antwerp, Belgium, more than 1500 individual Pb-containing aerosol particles with projected diameters between 0.2 and 15 μm were analyzed by automated electron probe X-ray micro analysis (EPXMA) for 26 elements and morphological features. Laser microprobe mass analysis (LAMMA) was used to detect elements with Z < 11, particularly ammonium compounds. The Pb-containing particles were classified into five main classes: Pb-sulfates, Pb-halides, soil related Pb, Pb associated with medium atomic number elements and Pb associated with high atomic number elements. Each class was divided into several distinct particle types, of which the abundance (in number and mass %), the mean projected particle diameter, and the chemical composition were determined. Auto exhaust products are responsible for Pb-sulfates and Pb-halides, making up respectively 66.7 and 27.8% by mass of the Pb-containing particles. Ammonium sulfate coatings were found to be present on nearly all Pb particles. The observations were correlated with daily concentrations of Pb and Br, obtained by particle induced X-ray emission analysis (PIXE).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1990CJ43500005	Publication Date	2003-09-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0048-9697; 1879-1026	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:116651			Serial	8169
Permanent link to this record



	Author	Stranger, M.; Krata, A.; Kontozova-Deutsch, V.; Bencs, L.; Deutsch, F.; Worobiec, A.; Naveau, I.; Roekens, E.; Van Grieken, R.
	Title	Monitoring of NO₂ in the ambient air with passive samplers before and after a road reconstruction event			Type	A1 Journal article
	Year	2008	Publication	Microchemical journal	Abbreviated Journal
	Volume	90	Issue	2	Pages	93-98
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
	Abstract	Nitrogen dioxide (NO2) concentrations were used to evaluate the air quality before and after the infrastructural change of an important traffic artery in Mortsel, Antwerp (Belgium). During the reconstruction works two pairs of traffic lanes were reduced to one in each direction. Two sampling campaigns were conducted: the first one before the works in 2003 and the second one in 2005, after the road works were finished. Sampling was performed on a weekly base with the use of passive diffusion tubes on the streets, and also indoors in nearby houses. The samples were analyzed by ion chromatography, from which data the NO2 concentrations in air could be calculated. These results were compared with NO2 values from the air monitoring station 42R801 of the Flemish Environment Agency in Borgerhout, Antwerp. On the base of different NO2 concentrations, correlated well with the traffic density, sampling locations were classified into three groups as follows: 1) heavily polluted (heavy traffic); 2) moderately polluted (medium traffic); or 3) less polluted (low traffic density). Sampling sites located further from the road works, enclosed to the group less polluted, showedthe lowestNO2 concentrations. The highestNO2 levelwas found for the locations close to reconstructionworks, which belonged to the group heavily polluted. The contribution of NO2 was at the samelevel before and after the roadworks. During the first campaign it ranged from30±7 µg/m3 to 71±11 µg/m3 and during the second sampling itwas between 36±17 µg/m3 and 73±17 µg/m3. These modernizationworks had no impact on preventing the traffic-related pollutant as NO2 and as a consequence no significant effect on the air quality in the studied region. It has been proven that the impact of traffic on the air quality is unmistakably high and simply reduction of the number of the traffic lanes, intended to discourage the traffic flow, had apparently no environmentally advantageous effect
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000261084200002	Publication Date	2008-04-18
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:71076			Serial	8276
Permanent link to this record



	Author	Mihucz, V.G.; Varga, Z.; Tatár, E.; Virág, I.; Van Grieken, R.; Koleszár, Z.; Záray, G.
	Title	Redistribution of uranium and thorium by soil/plant interaction in a recultivated mining area			Type	A1 Journal article
	Year	2008	Publication	Microchemical journal	Abbreviated Journal
	Volume	90	Issue	1	Pages	44-49
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	During the recultivation of the uranium mining area of Kõvágószõlõs (Hungary), the tailings were covered with clay and loess soil layers having a thickness of 30 cm and 100 cm, respectively. In the loess covering layer, acacia (Robinia pseudoacacia), poplars (Populus × albus, Populus × canescens), oak (Quercus pubescens), silver tree (Eleagnus angustifolia) were planted between 1996 and 2004. In order to establish the extent of the uranium and thorium transport from the sludge to the leaves by uptake and translocation processes through roots with a length higher than 1.3 m results in a remarkable redistribution of these pollutants, a gray poplar tree, growing spontaneously in the last uncovered tailing, being selected as reference tree. The U and Th concentrations in the leaves of the above-mentioned trees, in the covering layers as well as in the original sludge were determined by inductively coupled plasma sector field mass spectrometry (ICP-SF-MS). Generally, the Th concentration of the soils was about 4 times higher than that of uranium, while uranium concentration was about 10130 times higher than that of thorium in the leaf samples and its concentration ranged from 28 to 1045 ng g− 1, the last value belonging to the poplar tree growing on the last uncovered tailing. In order to assume the mobility and bioavailability of uranium if the dry leaves fall down, the uranium species in the leaves of the poplar tree growing in the uncovered reservoir were determined applying ultrasound-assisted extraction with distilled water and ammonium acetate as well as high performance liquid chromatographic (HPLC)-ICP-SF-MS technique. About 20% of total uranium could be extracted in form of uranyl cations and a presumably negatively charged uranium compound. Estimations revealed that the annual increment of U in the soil surface layer due to the dead fallen leaves in case of the investigated gray poplar (Populus × canescens) is about 1.2%.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000258744000008	Publication Date	2008-03-21
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:70717			Serial	8464
Permanent link to this record



	Author	Worobiec, A.; Samek, L.; Karaszkiewicz, P.; Kontozova-Deutsch, V.; Stefaniak, E.A.; van Meel, K.; Krata, A.; Bencs, L.; Van Grieken, R.
	Title	A seasonal study of atmospheric conditions influenced by the intensive tourist flow in the Royal Museum of Wawel Castle in Cracow, Poland			Type	A1 Journal article
	Year	2008	Publication	Microchemical journal	Abbreviated Journal
	Volume	90	Issue	2	Pages	99-106
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
	Abstract	Increasingmass tourismcan generate importantmicroclimatic perturbations and also elevate indoor pollution by the transport of fine particulatematter. The purpose of this researchwas to study the indoor air conditions in the RoyalMuseum ofWawel Castle in Cracow, Poland, displaying amongst other valuable works of art also a unique collection of Flemish tapestries. The investigation involved in the determination of transport and deposition of particulate matter brought in by visitors. The microclimate inside the exhibition rooms was also monitored. Samples of suspended particulateswere collected inside and outside themuseuminwinterand summer2006.On days with intensive tourist visits the concentration of total suspended particulates was significantly higher (i.e., 130 µg/m3 inwinter and 49 µg/m3 in summer) than on those days without tourists (i.e., 73 µg/m3 and 22 µg/m3 in winter and summer, respectively). The concentrations of all investigated elementswere also considerably higher during the tourist flow. This was especially valid for soil dust associated elements (Si, K, Ca, Al, and Ti), with considerably higher levels in summer than winter. This could be linked with much more frequent tourist activity in the summer period. Also, the concentration of Clwasmuch higher inwinter than summer, due to the use of deicing salts on the roads and pavements.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000261084200003	Publication Date	2008-04-27
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:70988			Serial	8500
Permanent link to this record



	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	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
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	Author	Vanderborght, B.; Van Grieken, R.
	Title	Reduction of trace metal levels in analytical-grade activated carbon			Type	A1 Journal article
	Year	1977	Publication	Analytica chimica acta	Abbreviated Journal
	Volume	89	Issue	2	Pages	399-402
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1977DB52500022	Publication Date	2002-07-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2670; 1873-4324	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:116368			Serial	8466
Permanent link to this record



	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	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
Permanent link to this record



	Author	Maenhaut, W.; Raemdonck, H.; Selen, A.; Van Grieken, R.; Winchester, J.W.
	Title	Characterization of the atmospheric aerosol over the eastern equatorial Pacific			Type	A1 Journal article
	Year	1983	Publication	Journal of geophysical research	Abbreviated Journal
	Volume	88	Issue	C:9	Pages	5353-5364
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	By using a polyester sailboat as sampling platform, a series of duplicate aerosol samples was collected by cascade impactors on a trip from Panama to Tahiti in 1979. Elemental analysis mainly by particle-induced X ray emission (PIXE) indicated, in the samples collected between Panama and the Galapagos Islands, the presence of a substantial crustal component (∼0.4 μg/m3), fine Cu (∼0.4 ng/m3) and Zn (∼0.6 ng/m3), and excess fine S and K (∼100 and ∼2.4 ng/m3, respectively) in addition to the major sea salt elements. The crustal component and fine Cu and Zn are suggested to result from natural continental sources (i.e., eolian dust transport from the American continents and perhaps geothermal emissions). Samples collected west of the Galapagos Islands in the southern trades showed significantly lower concentrations for the nonseawater components. The average Si and Fe levels were as low as 4.8 and 3.3 ng/m3, corresponding to a maximum of 0.066 μg/m3 for an assumed mineral dust component, whereas heavy metal concentrations were all below the detection limits (typically ranging from 0.05 to 0.15 ng/m3 for V, Cr, Mn, Ni, Cu, Zn, and Se). Excess fine S decreased to a mean of 46 ng/m3, a level similar to those reported for other remote marine and continental locations. This all indicates that the marine atmosphere west of the Galapagos was little influenced by natural continental source processes or by anthropogenic emissions. Under these truly marine conditions, several concentration ratios of the major seawater elements were significantly different from those in bulk seawater. Ca, Sr, and S in >1 μm diameter particles were enriched relative to K and Na, with the enrichment being substantially more pronounced (up to 50% or higher) for l4-μm diameter particles than for particles >4 μm. Comparison of these data with a similar data set from samples collected over the Atlantic indicates that the departures from seawater composition are significantly larger for the Pacific. Differences in sea-to-air fractionation processes, probably involving binding of divalent cations to organic matter in the oceanic surface microlayer, are suggested as being responsible for these observations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1983QU67600025	Publication Date	2008-02-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0148-0227; 2156-2202; 0022-1406; 0196-6928; 0196-6936; 0885-3401; 8755-8556; 0196-2256; 0747-7309; 1	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:113625			Serial	7633
Permanent link to this record



	Author	Alfeld, M.; Broekaert, J.A.C.
	Title	Mobile depth profiling and sub-surface imaging techniques for historical paintings : a review			Type	A1 Journal article
	Year	2013	Publication	Spectrochimica acta: part B : atomic spectroscopy	Abbreviated Journal
	Volume	88	Issue		Pages	211-230
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Hidden, sub-surface paint layers and features contain valuable information for the art-historical investigation of a painting's past and for its conservation for coming generations. The number of techniques available for the study of these features has been considerably extended in the last decades and established techniques have been refined. This review focuses on mobile non-destructive subsurface imaging and depth profiling techniques, which allow for the in-situ investigation of easel paintings, i.e. paintings on a portable support. Among the techniques discussed are: X-ray radiography and infrared reflectography, which are long established methods and are in use for several decades. Their capabilities of element/species specific imaging have been extended by the introduction of energy/wavelength resolved measurements. Scanning macro-X-ray fluorescence analysis made it for the first time possible to acquire elemental distribution images in-situ and optical coherence tomography allows for the non-destructive study the surface paint layers in virtual cross-sections. These techniques and their variants are presented next to other techniques, such as Terahertz imaging, Nuclear Magnetic Resonance depth profiling and established techniques for non destructive testing (thermography, ultrasonic imaging and laser based interference methods) applied in the conservation of historical paintings. Next to selected case studies the capabilities and limitations of the techniques are discussed. (C) 2013 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000325838900028	Publication Date	2013-07-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0584-8547; 1873-3565	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:112232			Serial	8256
Permanent link to this record



	Author	Smits, J.; Van Grieken, R.
	Title	Optimization of a simple spotting procedure for x-ray fluorescence analysis of waters			Type	A1 Journal article
	Year	1977	Publication	Analytica chimica acta	Abbreviated Journal
	Volume	88	Issue	1	Pages	97-107
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Several sample preparation methods for waters for energy-dispersive x.r.f. were examined, as well as the influence of sample size on the analytical characteristics. The most satisfactory simple, rapid method proved to be spotting of 1.5 ml of water sample on a Whatman-41 cellulose filter paper provided with a wax ring of 29-mm diameter and evaporating the water with an unheated air stream from underneath. Sensitivities are below 100 p.p.b. for most elements and often below 50 p.p.b. when the optimal secondary fluorescer is used. Accuracy and precision are usually in the 1520 % range. The method is applicable to many dilute aqueous solutions as is illustrated by analysis of industrial water samples and ashed biological material.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1977CQ82600011	Publication Date	2002-07-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2670; 1873-4324	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:116367			Serial	8337
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	Author	Ranjbari, E.; Hadjmohammadi, M.R.; Kiekens, F.; De Wael, K.
	Title	Mixed hemi/ad-micelle sodium dodecyl sulfate-coated magnetic iron oxide nanoparticles for the efficient removal and trace determination of rhodamine-B and rhodamine-6G			Type	A1 Journal article
	Year	2015	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	87	Issue	15	Pages	7894-7901
	Keywords	A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Mixed hemi/ad-micelle sodium dodecyl sulfate (SDS)-coated magnetic iron oxide nanoparticles (MHAMS-MIONPs) were used as an efficient adsorbent for both removal and preconcentration of two important carcinogenic xanthine dyes named rhodamine-B (RB) and rhodamine-6G (RG). To gain insight in the configuration of SDS molecules on the surface of MIONPs, zeta potential measurements were performed in different [SDS]/[MIONP] ratios. Zeta potential data indicated that mixed hemi/ad-micelle MHAM was formed in [SDS]/[MIONP] ratios over the range of 1.1 to 7.3. Parameters affecting the adsorption of dyes were optimized as removal efficiency by one variable at-a-time and response surface methodology; the obtained removal efficiencies were ∼100%. Adsorption kinetic and equilibrium studies, under the optimum condition (pH = 2; amount of MIONPs = 87.15 mg; [SDS]/[MIONP] ratio = 2.9), showed that adsorption of both dyes are based on the pseudo-second-order and the Langmuir isotherm models, respectively. The maximum adsorption capacities for RB and RG were 385 and 323 mg g1, respectively. MHAMS-MIONPs were also applied for extraction of RB and RG. Under optimum conditions (pH = 2; amount of damped MHAMS-MIONPs = 90 mg; eluent solvent volume = 2.6 mL of 3% acetic acid in acetonitrile), extraction recoveries for 0.5 mg L1 of RB and RG were 98% and 99%, with preconcentration factors of 327 and 330, respectively. Limit of detection obtained for rhodamine dyes were <0.7 ng mL1. Finally, MHAMS-MIONPs were successfully applied for both removal and trace determination of RB and RG in environmental and wastewater samples.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000359277900056	Publication Date	2015-07-08
	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	6.32	Times cited	36	Open Access
	Notes	; ;			Approved	Most recent IF: 6.32; 2015 IF: 5.636
	Call Number	UA @ admin @ c:irua:126583			Serial	5730
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	Author	Idris, A.M.; Eltayeb, M.A.H.; Potgieter-Vermaak, S.S.; Van Grieken, R.; Potgieter, J.H.
	Title	Assessment of heavy metals pollution in Sudanese harbours along the Red Sea Coast			Type	A1 Journal article
	Year	2007	Publication	Microchemical journal	Abbreviated Journal
	Volume	87	Issue	2	Pages	104-112
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000251750000003	Publication Date	2007-07-05
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:66067			Serial	7504
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	Author	Kabsch-Korbutowicz, M.; Krupinska, B.
	Title	Removal of natural organic matter from water by using ion-exchange resins			Type	A1 Journal article
	Year	2008	Publication	Przemysl chemiczny T2 – Scientific and Technical Conference on Water and Wastewater Basis for, Environmental Protection (School of Quality Water 2008), MAY 28-30, 2008, Kolobrzeg, POLAND	Abbreviated Journal
	Volume	87	Issue	5	Pages	473-475
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Four aq. solns. contg. natural peat components and the water from Odra river were treated with 3 anion-exchange resins (2.5 to 15 cm(3) of resin per 1 dm(3) of the sample) for 5-60 min to remove the org. matter. The process efficiency was detd. by UV absorbance (254 nm) and colour intensity measurements. The treatment resulted in discoloration of the solns. A resin with weak alky, was the most efficient. The degree of removal increased with increasing the resin dose and contact time. The presence of inorg. anions in the soins. contributed to a decrease of process effectivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000257179000020	Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0033-2496	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:102617			Serial	8471
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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	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	Monico, L.; Janssens, K.; Vanmeert, F.; Cotte, M.; Brunetti, B.G.; van der Snickt, G.; Leeuwestein, M.; Plisson, J.S.; Menu, M.; Miliani, C.
	Title	Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : part 5 : effects of nonoriginal surface coatings into the nature and distribution of chromium and sulfur species in chrome yellow paints			Type	A1 Journal article
	Year	2014	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	86	Issue	21	Pages	10804-10811
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The darkening of lead chromate yellow pigments, caused by a reduction of the chromate ions to Cr(III) compounds, is known to affect the appearance of several paintings by Vincent van Gogh. In previous papers of this series, we demonstrated that the darkening is activated by light and depends on the chemical composition and crystalline structure of the pigments. In this work, the results of Part 2 are extended and complemented with a new study aimed at deepening the knowledge of the nature and distribution of Cr and S species at the interface between the chrome yellow paint and the nonoriginal coating layer. For this purpose, three microsamples from two varnished paintings by Van Gogh and a waxed low relief by Gauguin (all originally uncoated) have been examined. Because nonoriginal coatings are often present in artwork by Van Gogh and contemporaries, the understanding of whether or not their application has influenced the morphological and/or physicochemical properties of the chrome yellow paint underneath is relevant in view of the conservation of these masterpieces. In all the samples studied, microscopic X-ray fluorescence (mu-XRF) and X-ray absorption near edge structure (mu-XANES) investigations showed that Cr(III)-based alteration products are present in the form of grains inside the coating (generally enriched of S species) and also homogeneously widespread at the paint surface. The distribution of Cr(III) species may be explained by the mechanical friction caused by the coating application by brush that picked up and redistributed the superficial Cr compounds, likely already present in the reduced state as result of the photodegradation process. The analysis of the XANES profiles allowed us to obtain new insights into the nature of the Cr(III) alteration products, that were identified as sulfate-, oxide-, organo-metal-, and chloride-based compounds. Building upon the knowledge acquired through the examination of original paint samples and from the investigation of aged model paints in the last Part 4 paper, in this study we aim to characterize a possible relation between the chemical composition of the coating and the chrome yellow degradation pathways by studying photochemically aged model samples covered with a dammar varnish contaminated with sulfide and sulfate salts. Cr speciation results did not show any evidence of the active role of the varnish and added S species on the reduction process of chrome yellows.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000344510200043	Publication Date	2014-10-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700; 5206-882x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.32	Times cited	25	Open Access
	Notes	; This research was supported by the Italian projects PRIN (SICH) and PON (ITACHA). The text also presents results from Interuniversity Attraction Poles Programme Belgian Science Policy (S2-ART project S4DA), GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. ESRF is acknowledged for the grants received (experiments EC-799 and EC-1051). L.M. acknowledges the CNR for the financial support received in the framework of the Short Term Mobility Programme 2013. Thanks are expressed to Ella Hendriks (Van Gogh Museum, Amsterdam) and Muriel Geldof (Cultural Heritage Agency of The Netherlands) for selecting and sharing the information on the cross-section taken from Bank of the Seine. All the staff of the Van Gogh Museum, the Kroller-Muller Museum, and the Musee d'Orsay are acknowledged for the agreeable cooperation. ;			Approved	Most recent IF: 6.32; 2014 IF: 5.636
	Call Number	UA @ admin @ c:irua:122100			Serial	5570
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