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Author Janssens, K.; Legrand, S.; van der Snickt, G.; Vanmeert, F. pdf  doi
openurl 
  Title Virtual archaeology of altered paintings : multiscale chemical imaging tools Type A1 Journal article
  Year 2016 Publication Elements Abbreviated Journal Elements  
  Volume 12 Issue 1 Pages 39-44  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Understanding how painted works of art were constructed, layer-by-layer, requires a range of macroscopic and microscopic X-ray and infrared-based analytical methods. Deconstructing complex assemblies of paints horizontally across a picture and vertically through it provides insight into the detailed production process of the art work and on the painting techniques and styles of its maker. The unwanted chemical transformations that some paint pigments undergo are also detectable; these changes can alter the paint's optical properties. Understanding the chemistry behind such paint degradation gives conservators vital clues to counter these effects and is an invaluable asset in protecting these cultural artefacts for future generations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000370987700007 Publication Date 2016-02-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1811-5209 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.038 Times cited 12 Open Access  
  Notes ; ; Approved Most recent IF: 4.038  
  Call Number UA @ admin @ c:irua:132301 Serial 5904  
Permanent link to this record
 

 
Author Zanin, L.; Tomasi, N.; Rizzardo, C.; Gottardi, S.; Terzano, R.; Alfeld, M.; Janssens, K.; De Nobili, M.; Mimmo, T.; Cesco, S. pdf  doi
openurl 
  Title Iron allocation in leaves of Fe-deficient cucumber plants fed with natural Fe complexes Type A1 Journal article
  Year 2015 Publication Physiologia plantarum Abbreviated Journal Physiol Plantarum  
  Volume 154 Issue 1 Pages 82-94  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Iron (Fe) sources available for plants in the rhizospheric solution are mainly a mixture of complexes between Fe and organic ligands, including phytosiderophores (PS) and water-extractable humic substances (WEHS). In comparison with the other Fe sources, Fe-WEHS are more efficiently used by plants, and experimental evidences show that Fe translocation contributes to this better response. On the other hand, very little is known on the mechanisms involved in Fe allocation in leaves. In this work, physiological and molecular processes involved in Fe distribution in leaves of Fe-deficient Cucumis sativus supplied with Fe-PS or Fe-WEHS up to 5days were studied combining different techniques, such as radiochemical experiments, synchrotron micro X-ray fluorescence, real-time reverse transcription polymerase chain reaction and in situ hybridization. In Fe-WEHS-fed plants, Fe was rapidly (1day) allocated into the leaf veins, and after 5days, Fe was completely transferred into interveinal cells; moreover, the amount of accumulated Fe was much higher than with Fe-PS. This redistribution in Fe-WEHS plants was associated with an upregulation of genes encoding a ferric(III)-chelate reductase (FRO), a Fe2+ transporter (IRT1) and a natural resistance-associated macrophage protein (NRAMP). The localization of FRO and IRT1 transcripts next to the midveins, beside that of NRAMP in the interveinal area, may suggest a rapid and efficient response induced by the presence of Fe-WEHS in the extra-radical solution for the allocation in leaves of high amounts of Fe. In conclusion, Fe is more efficiently used when chelated to WEHS than PS and seems to involve Fe distribution and gene regulation of Fe acquisition mechanisms operating in leaves.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000353067500007 Publication Date 2014-10-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9317 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.33 Times cited 14 Open Access  
  Notes ; Research was supported by grants from Italian MIUR (FIRB-Programma 'Futuro in Ricerca') and Free University of Bolzano (TN5056). Synchrotron experiments at HASYLAB were financially supported by the European Community-Research Infrastructure Action under the FP6 'Structuring the European Research Area' Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). We thank Karen Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; Approved Most recent IF: 3.33; 2015 IF: 3.138  
  Call Number UA @ admin @ c:irua:132500 Serial 5678  
Permanent link to this record
 

 
Author Thirumalraj, alamurugan; Palanisamy, S.; Chen, S.-M.; De Wael, K. pdf  url
doi  openurl
  Title A graphene/gelatin composite material for the entrapment of hemoglobin for bioelectrochemical sensing applications Type A1 Journal article
  Year 2016 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc  
  Volume 163 Issue 7 Pages 265-271  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract In the present work, a novel graphene (GN) and gelatin (GTN) composite was prepared and used as an immobilization matrix for hemoglobin (Hb). Compared with Hb immobilized on a bare, GN or GTN modified glassy carbon electrode (GCE), a stable and pair of well-defined quasi redox couple was observed at an Hb modified GN/GTN composite GCE at a formal potential of −0.306 V versus Ag|AgCl. The direct electrochemical behavior of Hb was greatly enhanced by the presence of both GTN and GN. A heterogeneous electron transfer rate constant (Ks) was calculated as 3.82 s−1 for Hb immobilized at GN/GTN modified GCE, which indicates the fast direct electron transfer of Hb toward the electrode surface. The biosensor shows a stable and wide linear response for H2O2 in the linear response range from 0.1 μM to 786.6 μM with an analytical sensitivity and limit of detection of 0.48 μAμM−1 cm−2 and 0.04 μM, respectively. The fabricated biosensor holds its high selectivity in the presence of potentially active interfering species and metal ions. The biosensor shows its satisfactory practical ability in the commercial contact lens solution and human serum samples.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000377412900047 Publication Date 2016-04-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0013-4651 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.259 Times cited 9 Open Access  
  Notes ; This project was supported by the Ministry of Science and Technology (project no. NSC1012113M027001MY3), Taiwan (Republic of China). The authors express their sincere thanks to Prof. Bih-Show Lou, Chemistry Division, Center for General Education, Chang Gung University, Tao-Yuan, Taiwan for providing the human serum samples. ; Approved Most recent IF: 3.259  
  Call Number UA @ admin @ c:irua:132627 Serial 5635  
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Author Trashin, S.; De Jong, M.; Meynen, V.; Dewilde, S.; De Wael, K. url  doi
openurl 
  Title Attaching redox proteins onto electrode surfaces by bis-silane Type A1 Journal article
  Year 2016 Publication ChemElectroChem Abbreviated Journal Chemelectrochem  
  Volume 3 Issue 7 Pages 1035-1038  
  Keywords A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Immobilization of redox proteins on electrode surfaces is of special interest for mechanistic studies and applications because of a well-controlled redox state of protein molecules by a polarized electrode and fast electron transfer kinetics, free from diffusion limitation. Here, bis-organosilane (1,2-bis(trimethoxysilyl)ethane) was applied as a fresh solution in a pH 7 phosphate buffer without use of any organic solvent, sol-gel or mesoporous bulk matrix. A short aging period of 30 minutes before deposition on the electrodes was optimal for the immobilization of proteins. Three redox proteins (cytochrome c, neuroglobin and GLB-12) were confined to the gold surface of electrodes with high coverages and stability, indicating that the suggested technique is simple, efficient and generic in nature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000380043500001 Publication Date 2016-03-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2196-0216 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.136 Times cited 4 Open Access  
  Notes ; The authors thank the Fund for Scientific Research-Flanders (FWO) (Grant G.0687.13) and the GOA-BOF UA 2013-2016 (project ID 28312) for funding. ; Approved Most recent IF: 4.136  
  Call Number UA @ admin @ c:irua:132628 Serial 5485  
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Author Van Hommes, M.E.; Lambour, R.; Du Mortier, B.M.; De Winkel, M.; Tauber, G.; Alfeld, M.; Janssens, K.; Dik, J. openurl 
  Title The hidden youth of Dirck Jacobsz leeuw : a portrait by Govert Flinck revealed Type A1 Journal article
  Year 2016 Publication The Rijksmuseum bulletin Abbreviated Journal  
  Volume 64 Issue 1 Pages 4-61  
  Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1877-8127 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes ; ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:133250 Serial 5873  
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Author Janssens, K.; van der Snickt, G.; Alfeld, M.; Noble, P.; van Loon, A.; Delaney, J.; Conover, D.; Zeibel, J.; Dik, J. pdf  doi
openurl 
  Title Rembrandt's 'Saul and David' (c. 1652) : use of multiple types of smalt evidenced by means of non-destructive imaging Type A1 Journal article
  Year 2016 Publication Microchemical journal Abbreviated Journal Microchem J  
  Volume 126 Issue Pages 515-523  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The painting Saul and David, considered to date from c. 1652 and previously attributed to Rembrandt van Rijn and/or his studio, is a complex work of art that has been recently subjected to intensive investigation and conservation treatment. The goal of the research was to give insight into the painting's physical construction and condition in preparation for conservation treatment. It was also anticipated that analysis would shed light on authenticity questions and Rembrandt's role in the creation of the painting. The painting depicts the Old Testament figures of King Saul and David. At left is Saul, seated, holding a spear and wiping a tear from his eye with a curtain. David kneels before him at the right playing his harp. In the past, the large sections with the life-size figures were cut apart and later reassembled. A third piece of canvas was added to replace a missing piece of canvas above the head of David. As part of the investigation into the authenticity of the curtain area, a number of paint micro samples were examined with LM and SEM-EDX. Given that the earth, smalt and lake pigments used in the painting could not be imaged with traditional imaging techniques, the entire painting was also examined with state of the art non-destructive imaging techniques. Special attention was devoted to the presence of cobalt-containing materials, specifically the blue glass pigment smalt considered characteristic for the late Rembrandt. A combination of quantitative electron microprobe analysis and macroscopic X-ray fluorescence scanning revealed that three types of cobalt-containing materials are present in the painting. The first type is a cobalt drier that was found in the overpaint used to cover up the canvas inset and the joins that were added in the 19th century. The other two Co-containing materials are part of the original paint used by Rembrandt and comprise two varieties of smalt, a K-rich glass pigment that derives its gray-blue color by doping with Co-ions. Smalt paint with a higher Ni content (NiO:CoO ratio of around 1:4) was used to depict the blue stripes in Saul's colorful turban, while smalt with a lower Ni content was employed (NiO:CoO ratio of around 1:5) for the broad expanses of Saul's garments. The presence of two types of smalt not only supports the recent re-attribution of the painting to Rembrandt, but also that the picture was painted in two phases. Saul's dark red garment is painted in a rough, “loose” manner and the now discolored smalt-rich layer was found to have been partially removed during a past restoration treatment/s. In contrast, the blue-green smalt in the turban is much better preserved and provides a colorful accent. While the use of different types of smalt in a Rembrandt painting has been previously identified using quantitative EDX analysis of paint cross-sections, to the best of our knowledge this is the first time such a distinction has been observed in a 17th-century painting using non-destructive imaging techniques. In addition to the XRF-based non-invasive elemental mapping, hyperspectral imaging in the visual to near-infrared (VNIR) region was also carried out. (C) 2016 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000373647500063 Publication Date 2016-01-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0026-265x; 0026-265x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.034 Times cited 18 Open Access  
  Notes ; This research is part of the ReVisualising late Rembrandt: Developing and Applying New Imaging Techniques research project, supported by the Science4Arts research program of the Netherlands Organisation for Scientific Research (NWO, The Hague, NL, ReVisRembrandt project) and the National Science Foundation (NSF, Washington DC, USA, award 1041827). We would like to thank colleagues of the Mauritshuis (The Hague, NL) and the Dutch Cultural Heritage Agency (RCE) in Rijswijk, NL for their support and assistance during the scanning of the Saul and David painting. The GOA project “SOLARPAINT” (University of Antwerp) and the Fund Baillet Latour (Brussels, B) are acknowledged for financial support to GvdS and KJ. We also like to acknowledge the help of Eliza Longhini and Stijn Legrand during some of the XRF scanning stages. ; Approved Most recent IF: 3.034  
  Call Number UA @ admin @ c:irua:133258 Serial 5813  
Permanent link to this record
 

 
Author Schalm, O.; Anaf, W. pdf  doi
openurl 
  Title Laminated altered layers in historical glass : density variations of silica nanoparticle random packings as explanation for the observed lamellae Type A1 Journal article
  Year 2016 Publication Journal of non-crystalline solids Abbreviated Journal  
  Volume 442 Issue Pages 1-16  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)  
  Abstract One of the most striking but unexplained phenomena in the natural degradation of glass is the transformation of an almost colorless, transparent and homogeneous glass into a colored, opaque and heterogeneous degradation layer. In many cases, the degradation layer consists of numerous lamellae with a thickness between 0.1 and 10 pm. However, both internal structure and formation proess of laminated degradation layers remain unclear. In this paper, a model is proposed where we assume that transformed (degraded) glass consists of a random packing of nano-sized silica particles while the lamellae are the result of different packing densities. The model is able to connect the texture of numerous lamellae observed by several types of microscopic techniques with the structure at molecular level determined by means of chemical analysis. In addition, the model is able to explain numerous properties such as the parameters responsible for the contrast between lamellae. This contrast can be caused by differences in color, density, elemental composition, or surface roughness. (C) 2016 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000375809800001 Publication Date 2016-04-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3093 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:133634 Serial 8146  
Permanent link to this record
 

 
Author Pilehvar, S. openurl 
  Title Development of new strategies for electrochemical aptasensing Type Doctoral thesis
  Year 2016 Publication Abbreviated Journal  
  Volume Issue Pages 198 p.  
  Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links (up) UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:133790 Serial 7802  
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Author Trashin, S.; De Jong, M.; Luyckx, E.; Dewilde, S.; De Wael, K. url  doi
openurl 
  Title Electrochemical evidence for neuroglobin activity on NO at physiological concentrations Type A1 Journal article
  Year 2016 Publication Journal of biological chemistry Abbreviated Journal J Biol Chem  
  Volume 291 Issue 36 Pages 18959-18966  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The true function of neuroglobin (Ngb) and, particularly, human Ngb (NGB) has been under debate since its discovery 15 years ago. It has been expected to play a role in oxygen binding/supply, but a variety of other functions have been put forward, including NO dioxygenase activity. However, in vitro studies that could unravel these potential roles have been hampered by the lack of an Ngb-specific reductase. In this work, we used electrochemical measurements to investigate the role of an intermittent internal disulfide bridge in determining NO oxidation kinetics at physiological NO concentrations. The use of a polarized electrode to efficiently interconvert the ferric (Fe3+) and ferrous (Fe2+) forms of an immobilized NGB showed that the disulfide bridge both defines the kinetics of NO dioxygenase activity and regulates appearance of the free ferrous deoxy-NGB, which is the redox active form of the protein in contrast to oxy-NGB. Our studies further identified a role for the distal histidine, interacting with the hexacoordinated iron atom of the heme, in oxidation kinetics. These findings may be relevant in vivo, for example in blocking apoptosis by reduction of ferric cytochrome c, and gentle tuning of NO concentration in the tissues.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000383242300031 Publication Date 2016-07-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9258; 1083-351x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.125 Times cited 11 Open Access  
  Notes ; This work was supported by Fonds Wetenschappelijk Onderzoek (FWO) Grant G.0687.13 and Universiteit Antwerpen GOA BOF 28312. The authors declare that they have no conflicts of interest with the contents of this article. ; Approved Most recent IF: 4.125  
  Call Number UA @ admin @ c:irua:134340 Serial 5590  
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Author Pauwels, D.; Pilehvar, S.; Geboes, B.; Hubin, A.; De Wael, K.; Breugelmans, T. pdf  url
doi  openurl
  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.  
  Address  
  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 (up) 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 Castanheiro, A.; Samson, R.; De Wael, K. pdf  url
doi  openurl
  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 (up) 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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Author Pilehvar, S.; Reinemann, C.; Bottari, F.; Vanderleyden, E.; Van Vlierberghe, S.; Blust, R.; Strehlitz, B.; De Wael, K. pdf  url
doi  openurl
  Title A joint action of aptamers and gold nanoparticles chemically trapped on a glassy carbon support for the electrochemical sensing of ofloxacin Type A1 Journal article
  Year 2017 Publication Sensors and actuators : B : chemical Abbreviated Journal Sensor Actuat B-Chem  
  Volume 240 Issue Pages 1024-1035  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A joint action of ssDNA aptamers and electrochemistry is a key element in developing successful biosensing platforms, since aptamers are capable of binding various targets with high specificity, and electrochemistry is one of the most sensitive techniques for on-site detections. A continuous search for improved immobilization and sensing strategies of aptamers on transducer surfaces resulted in the strategy presented in this article. The strategy is based on the covalent attachment of gold nanoparticles on the surface of glassy carbon electrodes through sulfhydryl-terminated monolayer, acting as a glue to connect AuNPs on the electrode. The covalently attached gold nanoparticles modified glassy carbon electrodes have been applied for the efficient immobilization of thiolated ssDNA probes, with a surface coverage of about 8.54 × 1013 molecules cm−2 which was 7-fold higher than that on the electrochemically deposited gold nanoparticles. Consequently, improved sensitivity, good reproducibility and stability are achieved for electrochemical aptasensor. Combined with the high affinity and specificity of an aptamer, a simple, novel, rapid, sensitive and label-free electrochemical aptasensor was successfully fabricated for ofloxacin (OFL) detection. The linear dynamic range of the sensor varies between 5 × 10−8 to 2 × 10−5 M OFL with a detection limit of 1 × 10−9 M OFL. A potential application in environmental monitoring was demonstrated by using this sensing strategy for the determination of OFL in (experimentally spiked) real samples such as tap water and effluent of sewage treatment plant. The proposed nanoaptasensor combines the advantages of the covalent attachment of neatly arranged AuNPs (enlarged active surface area and strengthened electrochemical signal) and the elimination of labels for the amplified detection of OFL, with the covalent attachment of highly specific aptamers to the surface of the modified electrode.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000390622300123 Publication Date 2016-09-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-4005 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.401 Times cited 21 Open Access  
  Notes ; This work was financially supported by the University of Antwerp (BOF), The Research Foundation – Flanders (FWO) and The Hercules Foundation. S. P. is thankful to UA for DOCPRO financial support. C.R. and B.S. acknowledge funding by the Federal Ministry of Education and Research (BMBF) under contract no. 03X0094B. ; Approved Most recent IF: 5.401  
  Call Number UA @ admin @ c:irua:135410 Serial 5682  
Permanent link to this record
 

 
Author Hamidi-Asl, E.; Dardenne, F.; Pilehvar, S.; Blust, R.; De Wael, K. url  doi
openurl 
  Title Unique properties of core shell Ag@Au nanoparticles for the aptasensing of bacterial cells Type A1 Journal article
  Year 2016 Publication Chemosensors Abbreviated Journal  
  Volume 4 Issue 3 Pages 16  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract In this article, it is shown that the efficiency of an electrochemical aptasensing device is influenced by the use of different nanoparticles (NPs) such as gold nanoparticles (Au), silver nanoparticles (Ag), hollow gold nanospheres (HGN), hollow silver nanospheres (HSN), silvergold core shell (Ag@Au), goldsilver core shell (Au@Ag), and silvergold alloy nanoparticles (Ag/Au). Among these nanomaterials, Ag@Au core shell NPs are advantageous for aptasensing applications because the core improves the physical properties and the shell provides chemical stability and biocompatibility for the immobilization of aptamers. Self-assembly of the NPs on a cysteamine film at the surface of a carbon paste electrode is followed by the immobilization of thiolated aptamers at these nanoframes. The nanostructured (Ag@Au) aptadevice for Escherichia coli as a target shows four times better performance in comparison to the response obtained at an aptamer modified planar gold electrode. A comparison with other (core shell) NPs is performed by cyclic voltammetry and differential pulse voltammetry. Also, the selectivity of the aptasensor is investigated using other kinds of bacteria. The synthesized NPs and the morphology of the modified electrode are characterized by UV-Vis absorption spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis, and electrochemical impedance spectroscopy.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000382480000006 Publication Date 2016-08-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2227-9040 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 9 Open Access  
  Notes ; Ezat Hamidi-Asl was financially supported by Belspo (University of Antwerp). The authors are thankful to Femke De Croock for her technical support and to Stanislav Trashin for his worthwhile comments on the manuscript. ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:135411 Serial 5886  
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Author Leyva Pernia, D.; Cabal Rodríguez, A.E.; Schalm, O.; van Espen, P.; Piñera Hernández, I.; Abreu Alfonso, Y. pdf  isbn
openurl 
  Title Study of the main physical processes contributing to image formation in emission radiography using mathematical modeling Type P3 Proceeding
  Year 2013 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords P3 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-959-7136-98-9 Additional Links (up) UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:135412 Serial 8607  
Permanent link to this record
 

 
Author Schalm, O.; Wouters, H.; Janssens, K. isbn  openurl
  Title Composition of 13-17th century glass from non-figurative windows in secular buildings excavated in Belgium Type P3 Proceeding
  Year 2005 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords P3 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 978-90-72290-05-2 Additional Links (up) UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:135440 Serial 5539  
Permanent link to this record
 

 
Author Schalm, O.; Caen, J.; Janssens, K. openurl 
  Title Chemical composition of 19th century window glass originating from stianed glass windows located in Belgium Type P2 Proceeding
  Year 2007 Publication Abbreviated Journal  
  Volume Issue Pages 169-178  
  Keywords P2 Proceeding; Engineering sciences. Technology; 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 978-2-930466-08-8 ISBN Additional Links (up) UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:135466 Serial 5513  
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Author Cosyns, P.; Janssens, K.; Vanderlinden, V.; Schalm, O. pdf  openurl
  Title Black glass vessels and jewellery in Belgium : production, context analysis, chronology and use Type P3 Proceeding
  Year 2005 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords P3 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links (up) UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:135467 Serial 5491  
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Author 't Hart, L.; Storme, P.; Anaf, W.; Nuyts, G.; Vanmeert, F.; Dorriné, W.; Janssens, K.; De Wael, K.; Schalm, O. pdf  url
doi  openurl
  Title Monitoring the impact of the indoor air quality on silver cultural heritage objects using passive and continuous corrosion rate assessments Type A1 Journal article
  Year 2016 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater  
  Volume 122 Issue 10 Pages 923-10  
  Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)  
  Abstract There is a long tradition in evaluating industrial atmospheres by measuring the corrosion rate of exposed metal coupons. The heritage community also uses this method, but the interpretation of the corrosion rate often lacks clarity due to the low corrosivity in indoor museum environments. This investigation explores the possibilities and drawbacks of different silver corrosion rate assessments. The corrosion rate is determined by three approaches: (1) chemical characterization of metal coupons using analytical techniques such as electrochemical measurements, SEM-EDX, XRD, and µ-Raman spectroscopy, (2) continuous corrosion monitoring methods based on electrical resistivity loss of a corroding nm-sized metal wire and weight gain of a corroding silver coated quartz crystal, and (3) characterization of the visual degradation of the metal coupons. This study confirms that subtle differences in corrosivity between locations inside a museum can be determined on condition that the same corrosion rate assessment is used. However, the impact of the coupon orientation with respect to the prevailing direction of air circulation can be substantially larger than the impact of the coupon location.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000384753800053 Publication Date 2016-09-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0947-8396 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.455 Times cited 3 Open Access  
  Notes ; This research has been sponsored by the Belgian Federal Public Planning Service Science Policy (BELSPO) under Project Number BR/132/A6/AIRCHECQ. In this project an innovative monitoring kit is developed that continuously and simultaneously measures both environmental parameters and material behaviour, enabling the study of the cause-effect relationships. The Quanta 250 FEG microscope at the University of Antwerp was funded by the Hercules foundation of the Flemish Government. ; Approved Most recent IF: 1.455  
  Call Number UA @ admin @ c:irua:135511 Serial 5733  
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Author Vermeulen, M.; Nuyts, G.; Sanyova, J.; Vila, A.; Buti, D.; Suuronen, J.-P.; Janssens, K. pdf  doi
openurl 
  Title Visualization of As(III) and As(V) distributions in degraded paint micro-samples from Baroque- and Rococo-era paintings Type A1 Journal article
  Year 2016 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 31 Issue 9 Pages 1913-1921  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Orpiment and realgar, both arsenic sulfide pigments respectively used for their vivid yellow and red-orange hues, are two of many artists' pigments that appear not to be stable upon light exposure, quickly degrading to arsenic trioxide and arsenate. This often results in whitening or transparency in the painted surfaces. While conventional techniques such as microscopic Raman (mu-RS) and microscopic Fourier transform infrared (mu-FTIR) spectroscopies can allow a quick and relatively easy identification of the orpiment, realgar, artificial arsenic sulfide glass and, to some extent, arsenic oxide, the identification and visualization of distributions of the degradation products – and especially arsenate compounds – in the paint micro-samples is generally more challenging. This challenge is due to the rather unfavorable limit of detection and low spectral resolution of such conventional spectroscopic techniques. This restricts the conclusions that can be drawn regarding the conservation state of valuable works of art. In this paper, we present how synchrotron radiation (SR) based techniques can overcome this challenge while working on painting cross-sections taken from a 17th-century painting by the Flemish artist Daniel Seghers (oil on canvas, Statens Museum for Kunst, Denmark) and an 18th-century French Chinoiserie (private collection, France). SR micro-X-ray fluorescence (m-XRF) mapping analysis performed on a visually degraded orpiment-containing paint stratigraphy reveals that arsenic is distributed throughout the entire cross-section, while X-ray absorption near edge structure (mu-XANES) demonstrated that the arsenic is present in both arsenite (As-III) and arsenate (As-V) forms. The latter compound(s), despite being barely identifiable by means of FTIR, were not only located at the surface of large and partially altered grains of arsenic sulfide but also spread throughout the entire paint stratigraphy. Their presence and distribution are attributed either to the complete degradation of smaller arsenic sulfide grains or to migration of the arsenates within the paint layer away from their original location of formation. The combination of mu-XRF and mu-XANES was very useful for the characterization of the advanced degradation state of the arsenic-containing pigments in paint systems; this type of information could not be obtained by means of conventional spectroscopic methods of microanalysis.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000382071200017 Publication Date 2016-08-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 20 Open Access  
  Notes ; This research is made possible with the support of the Belgian Science Policy Office (BELSPO) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (SD/RI/04A). The CATS gratefully acknowledge VILLUM FONDEN and VELUX FONDEN for infra-structural financial support as well as Anne Haack Christensen, Hannah Tempest and Johanne M. Nielsen for their help and suggestions. The European Synchrotron Radiation Facility is acknowledged for provision of synchrotron radiation facilities. ; Approved Most recent IF: 3.379  
  Call Number UA @ admin @ c:irua:135691 Serial 5907  
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Author Patiño, Y.; Pilehvar, S.; Díaz, E.; Ordóñez, S.; De Wael, K. pdf  url
doi  openurl
  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 (up) 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 Misseeuw, L.; Krajewska, A.; Pasternak, I.; Ciuk, T.; Strupinski, W.; Reekmans, G.; Adriaensens, P.; Geldof, D.; Geldof, D.; Van Vlierberghe, S.; Thienpont, H.; Dubruelf, P.; Vermeulen, N. pdf  doi
openurl 
  Title Optical-quality controllable wet-chemical doping of graphene through a uniform, transparent and low-roughness F4-TCNQ/MEK layer Type A1 Journal article
  Year 2016 Publication RSC advances Abbreviated Journal  
  Volume Issue 106 Pages 104491-104501  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Controllable chemical doping of graphene has already proven very useful for electronic applications, but when turning to optical and photonic applications, the additional requirement of having both a high transparency and a low surface roughness has, to our knowledge, not yet been fulfilled by any chemical dopant system reported so far. In this work, a new method that meets for the first time this opticalquality requirement while also providing efficient, controllable doping is presented. The method relies on F4-TCNQ dissolved in methyl ethyl ketone (MEK) yielding a uniform deposition after spin coating because of an extraordinary charge transfer interaction between the F4-TCNQ and MEK molecules. The formed F4-TCNQ/MEK layer exhibits a very high surface quality and optical transparency over the visible-infrared wavelength range between 550 and 1900 nm. By varying the dopant concentration of F4-TCNQ from 2.5 to 40 mg ml1 MEK, the doping effect can be controlled between Dn ¼ +5.73 1012 cm2 and +1.09 1013 cm2 for initially strongly p-type hydrogen-intercalated graphene grown on 6Hsilicon- carbide substrates, and between Dn ¼ +5.56 1012 cm2 and +1.04 1013 cm2 for initially weakly p-type graphene transferred on silicon samples. This is the first time that truly optical-quality chemical doping of graphene is demonstrated, and the obtained doping values exceed those reported before for F4-TCNQ-based graphene doping by as much as 50%.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000388111900075 Publication Date 2016-10-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:136405 Serial 8335  
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Author Martins, A.; Coddington, J.; van der Snickt, G.; van Driel, B.; McGlinchey, C.; Dahlberg, D.; Janssens, K.; Dik, J. doi  openurl
  Title Jackson Pollock's Number 1A, 1948 : a non-invasive study using macro-x-ray fluorescence mapping (MA-XRF) and multivariate curve resolution-alternating least squares (MCR-ALS) analysis Type A1 Journal article
  Year 2016 Publication Heritage science Abbreviated Journal  
  Volume 4 Issue Pages 33  
  Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Jackson Pollock's Number 1A, 1948 painting was investigated using in situ scanning macro-x-ray fluorescence mapping (MA-XRF) to help characterize the artist's materials and his creative process. A multivariate curve resolution-alternating least squares (MCR-ALS) approach was used to examine the hyperspectral data and obtain distribution maps and signature spectra for the paints he used. The composition of the paints was elucidated based on the chemical elements identified in the signature spectra and a tentative list of pigments, fillers and other additives is proposed for eleven different paints and for the canvas. The paint distribution maps were used to virtually reconstruct the artist process and document the sequence and manner in which Pollock applied the different paints, using deliberate and specific gestures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000386395100001 Publication Date 2016-09-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2050-7445 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:138172 Serial 8134  
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Author Godoi, R.H.M.; Goncalves, S.J., Jr.; Sayama, C.; Polezer, G.; Reis Neto, J.M.; Alfoldy, B.; Van Grieken, R.; Riedi, C.A.; Yamamoto, C.I.; Godoi, A.F.L.; Bencs, L. pdf  doi
openurl 
  Title Health implications of atmospheric aerosols from asbestos-bearing road pavements traditionally used in Southern Brazil Type A1 Journal article
  Year 2016 Publication Environmental Science and Pollution Research T2 – 1st International Caparica Conference on Pollutant Toxic Ions and, Molecules (PTIM), 2015, Caparica, PORTUGAL Abbreviated Journal  
  Volume 23 Issue 24 Pages 25180-25190  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Serpentine and amphibole asbestos occur naturally in certain geologic settings worldwide, most commonly in association with ultramafic rocks, along associated faults. Ultramafic rocks have been used in Pin County, Southern Brazil for decades for the purpose of road paving in rural and urban areas, but without the awareness of their adverse environmental and health impact. The aim of this study was the chemical characterization of aerosols re-suspended in two rural roads of Pin, paved with ultramafic rocks and to estimate the pulmonary deposition of asbestos aerosols. Bulk aerosol samples were analyzed by means of X-ray fluorescence spectrometry and X-ray diffraction analysis, in order to characterize elemental composition and crystallinity. Single-particle compositions of aerosols were analyzed by computer-controlled electron-probe microanalysis, indicating the presence of a few percentages of serpentine and amphibole. Given the chemical composition and size distribution of aerosol particles, the deposition efficiency of chrysotile, a sub-group of serpentine, in two principal segments of the human respiratory system was estimated using a lung deposition model. As an important finding, almost half of the inhaled particles were calculated to be deposited in the respiratory system. Asbestos depositions were significant (similar to 25 %) in the lower airways, even though the selected breathing conditions (rest situation, nose breathing) implied the lowest rate of respiratory deposition. Considering the fraction of inhalable suspended chrysotile near local roads, and the long-term exposure of humans to these aerosols, chrysotile may represent a hazard, regarding more frequent development of lung cancer in the population of the exposed region.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000389301700060 Publication Date 2016-09-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0944-1344; 1614-7499 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:139232 Serial 8018  
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Author Eliaerts, J.; Dardenne, P.; Meert, N.; Van Durme, F.; Samyn, N.; Janssens, K.; De Wael, K. url  doi
openurl 
  Title Rapid classification and quantification of cocaine in seized powders with ATR-FTIR and chemometrics Type A1 Journal article
  Year 2017 Publication Drug testing and analysis Abbreviated Journal Drug Test Anal  
  Volume 9 Issue 10 Pages 1480-1489  
  Keywords A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Traditionally, fast screening for the presence of cocaine in unknown powders is performed by means of colour tests. The major drawbacks of these tests are subjective colour evaluation depending on the operator (50 shades of blue) and a lack of selectivity. An alternative fast screening technique is Fourier Transform InfraRed (FTIR) spectrometry. This technique provides spectra that are difficult to interpret without specialized expertise and showing a lack of sensitivity for the detection of cocaine in mixtures. To overcome these limitations, a portable FTIR spectrometer using Attenuated Total Reflectance (ATR) sampling was combined with a multivariate technique, called Support Vector Machines (SVM). Representative street drug powders (n = 482), seized during the period January 2013 to July 2015, and reference powders (n = 33) were used to build and validate a classification model (n = 515) and a quantification model (n = 378). Both models were compared with the conventional chromatographic techniques. The SVM classification model showed a high sensitivity, specificity and efficiency (99%). The SVM quantification model determined cocaine content with a root mean squared error of prediction (RMSEP) of 6% calculated over a wide working range from 4 to 99 w%. In conclusion, the developed models resulted in a clear output (cocaine detected or cocaine not detected) and a reliable estimation of the cocaine content in a wide variety of mixtures. The ATR-FTIR technique combined with SVM is a straightforward, user-friendly and fast approach for routine classification and quantification of cocaine in seized powders.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000413685200001 Publication Date 2016-12-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1942-7603; 1942-7611 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.469 Times cited 9 Open Access  
  Notes ; ; Approved Most recent IF: 3.469  
  Call Number UA @ admin @ c:irua:139483 Serial 5799  
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Author Lybaert, J.; Trashin, S.; Maes, B.U.W.; De Wael, K.; Abbaspour Tehrani, K. pdf  url
doi  openurl
  Title Cooperative electrocatalytic and chemoselective alcohol oxidation by Shvo's catalyst Type A1 Journal article
  Year 2017 Publication Advanced synthesis and catalysis Abbreviated Journal Adv Synth Catal  
  Volume 359 Issue 6 Pages 919-925  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)  
  Abstract A new electrocatalytic conversion of alcohols to ketones and aldehydes was developed based on an electrochemical study of Shvos complex. The oxidation of secondary alcohols was efficiently performed under mild conditions using a catalytic amount of Shvos catalyst, in combination with a sub-stoichiometric amount of 2,6-dimethoxy-1,4- benzoquinone in N,N-dimethylformamide at 80 8C. The hydroquinone thus formed is continuously reoxidized with the aid of an electrochemical device. Excellent yields for different ketones, aromatic as well as aliphatic and a,b-unsaturated ketones, are obtained. In addition, chemoselectivity towards oxidation of the secondary alcohol is achieved when converting vicinal diols such as 1,2-octanediol and 1,2-decanediol.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000397584000003 Publication Date 2017-01-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1615-4150; 1615-4169 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.646 Times cited 4 Open Access  
  Notes ; This work was financially supported by the University of Antwerp (BOF), the Research Foundation – Flanders (FWO) and the Hercules Foundation. ; Approved Most recent IF: 5.646  
  Call Number UA @ admin @ c:irua:139795 Serial 5559  
Permanent link to this record
 

 
Author Janssens, K.; van der Snickt, G.; Vanmeert, F.; Legrand, S.; Nuyts, G.; Alfeld, M.; Monico, L.; Anaf, W.; de Nolf, W.; Vermeulen, M.; Verbeeck, J.; De Wael, K. pdf  doi
openurl 
  Title Non-invasive and non-destructive examination of artistic pigments, paints, and paintings by means of X-Ray methods Type A1 Journal article
  Year 2016 Publication Topics in Current Chemistry Abbreviated Journal Topics Curr Chem  
  Volume 374 Issue 374 Pages 81  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Recent studies are concisely reviewed, in which X-ray beams of (sub)micrometre to millimetre dimensions have been used for non-destructive analysis and characterization of pigments, minute paint samples, and/or entire paintings from the seventeenth to the early twentieth century painters. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging, as well as with the combined use of X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Microscopic XRF is a variant of the method that is well suited to visualize the elemental distribution of key elements, mostly metals, present in paint multi-layers, on the length scale from 1 to 100 μm inside micro-samples taken from paintings. In the context of the characterization of artists pigments subjected to natural degradation, the use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS and μ-XRD have proven themselves to be very suitable for such studies. Their use is often combined with microscopic Fourier transform infra-red spectroscopy and/or Raman microscopy since these methods deliver complementary information of high molecular specificity at more or less the same length scale as the X-ray microprobe techniques. Since microscopic investigation of a relatively limited number of minute paint samples, taken from a given work of art, may not yield representative information about the entire artefact, several methods for macroscopic, non-invasive imaging have recently been developed. Those based on XRF scanning and full-field hyperspectral imaging appear very promising; some recent published results are discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Springer international publishing ag Place of Publication Cham Editor  
  Language Wos 000391178900006 Publication Date 2016-11-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2365-0869;2364-8961; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.033 Times cited 50 Open Access  
  Notes ; ; Approved Most recent IF: 4.033  
  Call Number UA @ lucian @ c:irua:139930UA @ admin @ c:irua:139930 Serial 4443  
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Author Rahemi, V.; Sarmadian, N.; Anaf, W.; Janssens, K.; Lamoen, D.; Partoens, B.; De Wael, K. pdf  url
doi  openurl
  Title Unique opto-electronic structure and photo reduction properties of sulfur doped lead chromates explaining their instability in paintings Type A1 Journal article
  Year 2017 Publication Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 89 Issue 89 Pages 3326-3334  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artists material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0≤x≤0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods. Pure PbCrO4 (crocoite in its natural form) has a deep yellow color and is relatively stable, while the co-precipitate with lead sulfate (PbCr1-xSxO4) has a paler shade and seems to degrade faster. This degradation is assumed to be related to the reduction of Cr(VI) to Cr(III). We show that on increasing the sulfur(S)-content in chrome yellow, the band gap increases. Typically, when increasing the band gap, one might assume that a decrease in photo activity is the result. However, the photo activity relative to the Cr content, and thus Cr reduction, of sulfur-rich PbCr1-xSxO4 is found to be much higher compared to the sulfur-poor or non-doped lead chromates. This discrepancy can be explained by the evolution of the crystal and electronic structure as function of the sulfur content: first-principles density functional theory calculations show that both the absorption coefficient and reflection coefficients of the lead chromates change as a result of the sulfate doping in such a way that the generation of electron-hole pairs under illumination relative to the total Cr content increases. These changes in the material properties explain why paler shade yellow colors of this pigment are more prone to discoloration. The electronic structure calculations also demonstrate that lead chromate and its co-precipitates are p-type semiconductors, which explains the observed reduction reaction. As understanding this phenomenon is valuable in the field of cultural heritage, this study is the first joint action of photo-electrochemical measurements and first-principles calculations to approve the higher tendency of sulfur-rich lead chromates to darken.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000397478300015 Publication Date 2017-02-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2700 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 7 Open Access OpenAccess  
  Notes ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government, department EWI. The BOF-GOA action SOLARPAINT of the University of Antwerp Research Council is acknowledged for financial support. W.A. acknowledges support from BELSPO project S2-ART. Dr. L. Monico and Dr. C. Miliani (ISTM, Perugia) are gratefully acknowledged for helpful discussions and for providing some of the initial batches of the materials studied. ; Approved Most recent IF: 6.32  
  Call Number UA @ lucian @ c:irua:140886 Serial 4451  
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Author Cotte, M.; Checroun, E.; De Nolf, W.; Taniguchi, Y.; De Viguerie, L.; Burghammer, M.; Walter, P.; Rivard, C.; Salome, M.; Janssens, K.; Susini, J. pdf  doi
openurl 
  Title Lead soaps in paintings : friends or foes? Type A1 Journal article
  Year 2017 Publication Studies in conservation Abbreviated Journal Stud Conserv  
  Volume 62 Issue 1 Pages 2-23  
  Keywords A1 Journal article; Art; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The origin(s) and role(s) of metal soaps in paints are a worldwide concern today. These hybrid compounds, containing both fatty acid chains and metals associated with a carboxylate function, are increasingly identified in paints. As reviewed in the first part of this work, the presence of metal soaps in paints is differently interpreted in scientific publications: metal soaps are sometimes considered to play a positive role as anchor points, during paint drying processes; they can also be considered as responsible for many degradation processes (protrusions, efflorescences, darkening, etc.). Their origins are also interpreted in various ways. In some paintings (in particular from the twentieth century), they have sometimes introduced on purpose, as additives, to modify the physical properties of the painting materials. In older paintings, metal soaps are usually thought to result from an uncontrolled reaction of oil with lead-based pigments, in particular lead white, red lead, and lead tin yellow. In the second part of this work, the review of historical recipes of lead-based paint shows an important number of recipes based on controlled mixing of oil with lead driers. In the third part, the experimental reproduction of such traditional recipes using walnut oil and litharge (PbO) shows that lead soaps can be formed, both in about one hour at approximate to 100 degrees C, or in about one month at room temperature. It shows as well that after a few years, litharge is no longer detected in the paint medium, while different lead carbonates are. Finally, the micro-infrared spectroscopy and micro-X-ray diffraction re-analysis of protrusions from a nine-year model painting shows together with lead soaps, the presence of Pb-5(CO3)(3)(OH)(2)O ('synthetic plumbonacrite'), an unusual phase recently observed in a protrusion from a painting by Vincent Van Gogh. This work highlights (i) the multiple origins and roles of metal soaps in paints and (ii) the importance of combining the analysis of fragments from historical paintings with the analysis and reproduction of historical recipes. In particular, we show that the components detected today in historical paintings may severely differ from those originally used or prepared by the painter, complicating the assessment of the painter's intentions. More than the presence of metal soaps, the key questions to be tackled should be about their origins and (re)mobilization.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000393691200002 Publication Date 2016-10-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0039-3630; 2047-0584 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 0.578 Times cited 26 Open Access  
  Notes ; This work was supported by the European Synchrotron Radiation Facility. ; Approved Most recent IF: 0.578  
  Call Number UA @ admin @ c:irua:141976 Serial 5690  
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Author van der Snickt, G.; Dubois, H.; Sanyova, J.; Legrand, S.; Coudray, A.; Glaude, C.; Postec, M.; van Espen, P.; Janssens, K. pdf  doi
openurl 
  Title Large-area elemental imaging reveals Van Eyck's original paint layers on the Ghent altarpiece (1432), rescoping its conservation treatment Type A1 Journal article
  Year 2017 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 56 Issue 17 Pages 4797-4801  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A combination of large-scale and micro-scale elemental imaging, yielding elemental distribution maps obtained by, respectively non-invasive macroscopic X-ray fluorescence (MA-XRF) and by secondary electron microscopy/energy dispersive X-ray analysis (SEM-EDX) and synchrotron radiation-based micro-XRF (SR m-XRF) imaging was employed to reorient and optimize the conservation strategy of van Eyck's renowned Ghent Altarpiece. By exploiting the penetrative properties of X-rays together with the elemental specificity offered by XRF, it was possible to visualize the original paint layers by van Eyck hidden below the overpainted surface and to simultaneously assess their condition. The distribution of the high-energy Pb-L and Hg-L emission lines revealed the exact location of hidden paint losses, while Fe-K maps demonstrated how and where these lacunae were filled-up using an iron-containing material. The chemical maps nourished the scholarly debate on the overpaint removal with objective, chemical arguments, leading to the decision to remove all skillfully applied overpaints, hitherto interpreted as work by van Eyck. MA-XRF was also employed for monitoring the removal of the overpaint during the treatment phase. To gather complementary information on the in-depth layer build-up, SEM-EDX and SR mu-XRF imaging was used on paint cross sections to record microscale elemental maps.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000398576000019 Publication Date 2017-03-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-7851; 0570-0833 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 11 Open Access  
  Notes ; This research was supported by the Baillet Latour fund, the Belgian Science Policy Office (Projects MO/39/011) and the Gieskes-Strijbis fund. The authors are also indebted to the BOF-GOA SOLAR Paint project of the University of Antwerp Research Council. The church wardens of the cathedral of St. Bavo and their chairman L. Collin are acknowledged for this agreeable collaboration. We also wish to thank conservators L. Depuydt, B. De Volder, F. Rosier, N. Laquiere and G. Steyaert as well as the members of the international committee. We are indebted to Prof. Em. A. Van Grevenstein-Kruse. ; Approved Most recent IF: 11.994  
  Call Number UA @ admin @ c:irua:142376 Serial 5688  
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Author Cotte, M.; Pouyet, E.; Salome, M.; Rivard, C.; De Nolf, W.; Castillo-Michel, H.; Fabris, T.; Monico, L.; Janssens, K.; Wang, T.; Sciau, P.; Verger, L.; Cormier, L.; Dargaud, O.; Brun, E.; Bugnazet, D.; Fayard, B.; Hesse, B.; del Real, A.E.P.; Veronesi, G.; Langlois, J.; Balcar, N.; Vandenberghe, Y.; Sole, V.A.; Kieffer, J.; Barrett, R.; Cohen, C.; Cornu, C.; Baker, R.; Gagliardini, E.; Papillon, E.; Susini, J. doi  openurl
  Title The ID21 X-ray and infrared microscopy beamline at the ESRF: status and recent applications to artistic materials Type A1 Journal article
  Year 2017 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 32 Issue 3 Pages 477-493  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The ID21 beamline (European Synchrotron Radiation facility, France) is a multi micro-analytical platform combining X-ray and infrared micro-probes, for characterization of elements, species, molecular groups and crystalline structures in complex materials. Applications are mainly in the fields of cultural heritage, life science, environmental and earth sciences, materials sciences. Here, we first present the status of instruments: (i) the scanning micro-spectroscopy end-station, operating from 2.0 to 9.2 keV, under vacuum and offering cryo conditions, for the acquisition of 2D micro X-ray fluorescence (mu XRF) maps, single point micro X-ray Absorption Near Edge Structure (mu XANES) spectra and speciation maps with sub-micrometric resolution; (ii) the XANES full-field end-station, operating in the same vacuum and energy conditions, for the acquisition of hyper-spectral radiographs of thin concentrated samples, resulting in speciation maps with micrometric resolution and millimetric field of view; (iii) the scanning micro-X-ray diffraction (mu XRD)/mu XRF end-station, operating at 8.5 keV, in air, for the acquisition of 2D crystalline phase maps, with micrometric resolution; and (iv) the scanning infrared microscope, operating in the mid-infrared range for the acquisition of molecular maps and some structural maps with micrometric resolution. Recent hardware and software developments are presented, as well as new protocols for improved sample preparation of thin sections. Secondly, a review of recent applications for the study of cultural heritage is presented, illustrated by various examples: determination of the origin of the color in blue Chinese porcelains and in brown Sevres porcelains; detection of lead in ink on Herculaneum papyri; identification and degradation of modeling materials used by Auguste Rodin and of chrome yellow pigments used by Vincent van Gogh. Cryo capabilities are illustrated by the analysis of plants exposed to chromate solutions. These examples show the variety of materials analyzed, of questions tackled, and particularly the multiple advantages of the ID21 analytical platform for the analysis of ancient and artistic materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000396286900002 Publication Date 2016-12-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 39 Open Access  
  Notes ; ; Approved Most recent IF: 3.379  
  Call Number UA @ admin @ c:irua:142493 Serial 5874  
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