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Author Rather, J.A.; Pilehvar, S.; De Wael, K. pdf  doi
openurl 
  Title Polycyclodextrin and carbon nanotubes as composite for tyrosinase immobilization and its superior electrocatalytic activity towards butylparaben an endocrine disruptor Type A1 Journal article
  Year 2015 Publication Journal of nanoscience and nanotechnology Abbreviated Journal  
  Volume 15 Issue 5 Pages 3365-3372  
  Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract We developed a protocol for the immobilization of tyrosinase (Tyr) on the composite of polycyclodextrin polymer (CDP) and carbon nanotubes for the detection of an endocrine disruptor, i.e., butylparaben (BP). The formation of the CDP polymer was characterized by UV-Vis spectrophotometry. The conducting film of cross-linked CDP and carbon nanotubes, displays excellent matrix capabilities for Tyr immobilization. The host-guest chemical reaction ability of CD and the ππ stacking interaction assure the bioactivity of Tyr towards butylparaben. The developed biosensor was characterized electrochemically by electrochemical impedance spectroscopy. The enzyme-substrate kinetic parameters such as the apparent Michaelis-Menten constant (K M app) was measured under saturated substrate concentration. The determination of butylparaben was carried out by using square wave voltammetry over the concentration range of 2.1 to 35.4 μM with a detection limit of 0.1 μM. The fabricated biosensor was successfully applied in real-life cosmetic samples with good recovery ranging from 98.5 to 102.8%.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000347435200007 Publication Date 2014-10-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1533-4899 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 3 Open Access  
  Notes ; The authors are highly thankful for the mobility grant (Non-Europe Postdoc Fellowship) for one of the author (Jahangir Ahmad Rather) supported by the Belgian Federal Science Policy (Belspo) co-funded by the Marie Curie Actions from the European Commission. Sanaz Pilehvar is funded by BOF-DOCPRO UA. ; Approved Most recent IF: NA  
  Call Number (up) UA @ admin @ c:irua:119550 Serial 5776  
Permanent link to this record
 

 
Author Verbruggen, S.W.; Lenaerts, S.; Denys, S. pdf  url
doi  openurl
  Title Analytic versus CFD approach for kinetic modeling of gas phase photocatalysis Type A1 Journal article
  Year 2015 Publication Chemical engineering journal Abbreviated Journal Chem Eng J  
  Volume 262 Issue Pages 1-8  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In this work two methods for determining the LangmuirHinshelwood kinetic parameters for a slit-shaped flat bed photocatalytic reactor are compared: an analytic mass transfer based model adapted from literature and a computational fluid dynamics (CFD) approach that was used in conjunction with a simplex optimization routine. Despite the differences between both approaches, similar values for the kinetic parameters and similar trends in terms of their UV intensity dependence were found. Using an effectiveness-NTU (number of transfer units) approach, the analytic mass transfer based method could quantify the relative contributions of the rate limiting steps through a reaction effectiveness parameter. The numeric CFD approach on the other hand could yield the two kinetic parameters that determine the photocatalytic reaction rate simultaneously. Furthermore, it proved to be more accurate as it accounts for the spatial variation of flow rate, reaction rate and concentrations at the surface of the photocatalyst. We elaborate this dual kinetic analysis with regard to the photocatalytic degradation of acetaldehyde in air over a silicon wafer coated with a layer of TiO2 P25 (Evonik) and study the usefulness and limitations of both strategies.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000347577700001 Publication Date 2014-09-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1385-8947; 1873-3212 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.216 Times cited 30 Open Access  
  Notes ; S.W.V. acknowledges the Research Foundation of Flanders (FWO) for financial support. ; Approved Most recent IF: 6.216; 2015 IF: 4.321  
  Call Number (up) UA @ admin @ c:irua:119724 Serial 5927  
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Author Ayalew, E.; Gebre, Y.; De Wael, K. url  doi
openurl 
  Title A survey of occupational exposure to inhalable wood dust among workers in small- and medium-scale wood-processing enterprises in Ethiopia Type A1 Journal article
  Year 2015 Publication The annals of occupational hygiene Abbreviated Journal Ann Occup Hyg  
  Volume 59 Issue 2 Pages 253-257  
  Keywords A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A study of wood dust exposure in 20 small- and medium-scale wood-processing enterprises was performed in Ethiopia. Sampling was conducted daily from January to June, 2013 and a total of 360 samples from 113 workers were collected with Institute of Occupational Medicine (IOM) personal samplers. Eight-hour time-weighted average exposure to wood dust ranged from 0.24 to 23.3mg m−3 with a geometric mean (GM) of 6.82mg m−3 and a geometric standard deviation of 1.82. Although Ethiopia did not have any defined standard of Occupational Exposure Limit for wood dust exposure, 71% of the measurements exceeded the limit of 5mg m−3 set by the European Union (EU). Higher than the EU exposure limit was measured while workers perform sanding and sawing activities with a GM of 9.72 and 7.60mg m−3, respectively. In conclusion, wood workers in the small- and medium-scale enterprises are at a higher risk of developing different respiratory health problems with continuous exposure trends.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000352158700011 Publication Date 2014-10-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-4878 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.71 Times cited 4 Open Access  
  Notes ; Eyasu Ayalew thanks the Addis Ababa University (Center for Environmental Sciences) for the personal grant for independent study. ; Approved Most recent IF: 1.71; 2015 IF: 2.101  
  Call Number (up) UA @ admin @ c:irua:119739 Serial 5857  
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Author Anaf, W.; Bencs, L.; Van Grieken, R.; Janssens, K.; De Wael, K. pdf  url
doi  openurl
  Title Indoor particulate matter in four Belgian heritage sites : case studies on the deposition of dark-colored and hygroscopic particles Type A1 Journal article
  Year 2015 Publication The science of the total environment Abbreviated Journal Sci Total Environ  
  Volume 506 Issue Pages 361-368  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Atmospheric total suspended particulate (TSP) was passively sampled by means of deployed horizontal and vertical filters in various rooms of four Belgian cultural heritage buildings, installed with various heating/ventilation systems. Soiling/blackening and deposition of inorganic, water-soluble aerosol components were considered. The extent of soiling was determined by means of two independent methods: (1) in terms of the covering rate of the samplers by optical reflection microscopy and (2) the reduction in lightness of the samplers using the CIE L*a*b* color space by spectrophotometry. A fairly good correlation was found between both methods. The inorganic composition of the deposited water-soluble TSP was quantified by means of ion chromatography. Compared to controlled environments, uncontrolled environments showed increased water-soluble aerosol content of the total deposited mass. Higher chloride deposition was observed on horizontal surfaces, compared to vertical surfaces.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000347576800039 Publication Date 2014-11-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0048-9697 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.9 Times cited 12 Open Access  
  Notes ; ; Approved Most recent IF: 4.9; 2015 IF: 4.099  
  Call Number (up) UA @ admin @ c:irua:120640 Serial 5662  
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Author Buczyńska, A.J.; Geypens, B.; Van Grieken, R.; De Wael, K. pdf  url
doi  openurl
  Title Optimization of sample clean-up for the GC-C-IRMS and GC-IT-MS analysis of PAHs from air particulate matter Type A1 Journal article
  Year 2015 Publication Microchemical journal Abbreviated Journal Microchem J  
  Volume 119 Issue Pages 83-92  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The optimization of sample clean-up for the analysis of air particulate matter PAHs stable carbon isotope ratio using Solid Phase Extraction (SPE) cartridges is described in this paper. Various adsorbents, such as silica gel, alumina, florisil, commercially available for sample purification were compared. Best performance for the clean-up of 24-h air particulate matter samples was obtained with activated silica-gel columns in terms of selectivity and reproducibility. One step clean-up was optimized for concentration determination and in case of co-elutions, a second step was additionally used for carbon isotope ratio analysis. The method was subsequently validated with standard reference material and was checked for carbon isotope fractionation artefacts. No significant differences in δ13C values were found for unprocessed solutions of PAHs and solution subjected to the extraction and purification procedure. The procedure was tested on air particulate matter samples collected in three different locations in Belgium. Statistically significant differences in carbon isotope ratio of PAHs between Borgerhout location and Zelzate or Gent were noticed, confirming the differences in distribution and diagnostic ratios found during the concentration analyses and different PAH sources in these locations. The results, therefore, seem very promising for the use of δ13C of PAHs as an additional information helpful in source identification of these pollutants  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000348957800013 Publication Date 2014-11-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.034 Times cited 7 Open Access  
  Notes ; ; Approved Most recent IF: 3.034; 2015 IF: 2.746  
  Call Number (up) UA @ admin @ c:irua:120641 Serial 5759  
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Author Van Grieken, R. doi  openurl
  Title Introducing four new members of the editorial board of X-ray spectrometry Type Editorial
  Year 2015 Publication X-ray spectrometry Abbreviated Journal  
  Volume 44 Issue 1 Pages 1-2  
  Keywords Editorial; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000346727300001 Publication Date 2014-12-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0049-8246 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:123608 Serial 8119  
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Author Rossi, F.; Olguin, E.J.; Diels, L.; De Philippis, R. pdf  doi
openurl 
  Title Microbial fixation of CO2 in water bodies and in drylands to combat climate change, soil loss and desertification Type A1 Journal article
  Year 2015 Publication New biotechnology Abbreviated Journal  
  Volume 32 Issue 1 Pages 109-120  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The growing concern for the increase of the global warming effects due to anthropogenic activities raises the challenge of finding novel technological approaches to stabilize CO2 emissions in the atmosphere and counteract impinging interconnected issues such as desertification and loss of biodiversity. Biological-CO2 mitigation, triggered through biological fixation, is considered a promising and eco-sustainable method, mostly owing to its downstream benefits that can be exploited. Microorganisms such as cyanobacteria, green algae and some autotrophic bacteria could potentially fix CO2 more efficiently than higher plants, due to their faster growth. Some examples of the potential of biological-CO2 mitigation are reported and discussed in this paper. In arid and semiarid environments, soil carbon sequestration (CO2 fixation) by cyanobacteria and biological soil crusts is considered an eco-friendly and natural process to increase soil C content and a viable pathway to soil restoration after one disturbance event. Another way for biological-CO2 mitigation intensively studied in the last few years is related to the possibility to perform carbon dioxide sequestration using microalgae, obtaining at the same time bioproducts of industrial interest. Another possibility under study is the exploitation of specific chemotrophic bacteria, such as Ralstonia eutropha (or picketii) and related organisms, for CO2 fixation coupled with the production chemicals such as polyhydroxyalkanoates (PHAs). In spite of the potential of these processes, multiple factors still have to be optimized for maximum rate of CO2 fixation by these microorganisms. The optimization of culture conditions, including the optimal concentration of CO2 in the provided gas, the use of metabolic engineering and of dual purpose systems for the treatment of wastewater and production of biofuels and high value products within a biorefinery concept, the design of photobioreactors in the case of phototrophs are some of the issues that, among others, have to be addressed and tested for cost-effective CO2 sequestration.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000347507800015 Publication Date 2013-12-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1871-6784; 1876-4347 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:123762 Serial 8242  
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Author Jochems, P.; Mueller, T.; Satyawali, Y.; Diels, L.; Dejonghe, W.; Hanefeld, U. pdf  doi
openurl 
  Title Active site titration of immobilized beta-galactosidase for the determination of active enzymes Type A1 Journal article
  Year 2015 Publication Biochemical engineering journal Abbreviated Journal  
  Volume 93 Issue Pages 137-141  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In the present study, an active site titration method is demonstrated, to determine the amount of active enzyme (beta-galactosidase), immobilized on a support. Two types of supports were investigated, viz, amino acrylic resin and a mixed matrix membrane. Furthermore, 2',4'-dinitrophenyl 2-deoxy-2-fluoro-beta-D-galactopyranoside was used as an inhibitor for the active site titration of immobilized beta-galactosidase obtained from Kluyveromyces lactis. Using the active site titration, approximately 8.3 mg of active enzyme was found on 1 g of dried commercially available SPRIN imibond, which is an amino acrylic resin with covalently bound beta-galactosidase obtained from K. lactis. However, this method, in its present form, was not effective on the mixed matrix membranes due to the irreversible partial adsorption of the leaving group (2',4'-dinitrophenolate) by the membrane. This observation implied that it is important to investigate interactions between the support and the used inhibitor and leaving group. (C) 2014 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000347362100018 Publication Date 2014-10-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1369-703x; 1873-295x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:123763 Serial 7417  
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Author Liao, L.; Heylen, S.; Vallaey, B.; Keulemans, M.; Lenaerts, S.; Roeffaers, M.B.J.; Martens, J.A. pdf  doi
openurl 
  Title Photocatalytic carbon oxidation with nitric oxide Type A1 Journal article
  Year 2015 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ  
  Volume 166 Issue Pages 374-380  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The photocatalytic oxidation of carbon black on TiO2 using nitric oxide as an oxidizing agent was investigated. Layer-wise deposited carbon and TiO2 powder was illuminated with UVA light in the presence of NO at parts per million concentrations in dry and hydrated carrier gas at a temperature of 150 degrees C. Carbon was photocatalytically converted mainly into CO2, and NO mainly into N-2. Carbon oxidation rates of 7.2 mu g/h/mgTiO(2) were achieved in the presence of 3000 ppm NO. Under these experimental conditions in the absence of molecular oxygen, formation of surface nitrates causing TiO2 photocatalyst deactivation is suppressed. Addition of water enhances surface nitrate formation and catalyst deactivation. NO and carbon particulate matter are air pollutants emitted by diesel engines. Elimination of soot collected on a diesel particulate filter through oxidation is a demanding reaction requiring temperatures in excess of 250 degrees C. The present study opens perspectives for a low-temperature regeneration strategy for the diesel particulate filter that simultaneously performs DeNO(x) reactions. (C) 2014 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000348753400042 Publication Date 2014-12-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0926-3373 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.446 Times cited 5 Open Access  
  Notes ; This work was supported by long-term structural funding by the Flemish government (Methusalem). ; Approved Most recent IF: 9.446; 2015 IF: 7.435  
  Call Number (up) UA @ admin @ c:irua:123858 Serial 5977  
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Author Benito, P.; Monti, M.; de Nolf, W.; Nuyts, G.; Janssens, K.; et al. pdf  doi
openurl 
  Title Improvement in the coating homogeneity in electrosynthesized Rh structured catalysts for the partial oxidation of methane Type A1 Journal article
  Year 2015 Publication Catalysis today Abbreviated Journal Catal Today  
  Volume 246 Issue Pages 154-164  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The precipitation of Rh/Mg/Al and Rh/Al hydroxides on the surface of FeCrAlloy foams by a base electrogeneration method was investigated to improve the properties of the deposited film (homogeneity and composition) and therefore the performances of the structured catalysts, obtained by calcination, in the Catalytic Partial Oxidation of CH4 to syngas. The work focussed on decreasing current gradients within open-cell foam cylinders by increasing the number of electrical contacts from 1 to 3 points to promote a more homogeneous precipitation of the hydroxides. Electrochemical and catalytic tests as well as SEM/EDS and mu-XRFIXRD analyses allowed to correlate the effect of the number of electrical contact points with materials properties. Lastly, syntheses were performed on Pt plates to study the effect of the electrical behaviour and shape of the support on the composition of the film. A more homogeneous coating of the foam surface was achieved by adopting a configuration with 3 contact points since the reduction of nitrates and water molecules that generates the basic media in the vicinity of the support was enhanced. Layer thicknesses up to 5-15 mu m were deposited; however, the sequential precipitation of a film with composition closer to the expected one and a layer enriched in Al and Rh (outer layer) was not avoided. The improvement in the coating gave rise to enhanced performances for a sample prepared at -1.1 V for 3000 s. Contrarily, the low adherence of the outer layer in a sample prepared at -1.2 V for 2000 s during both calcination and catalytic tests may be responsible of the unexpected decrease in catalytic performances. The same sequential precipitation was observed by performing the syntheses on Pt plates, showing that the electrical nature the support did not play a key role on this phenomenon. (C) 2014 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000349998300020 Publication Date 2014-10-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0920-5861 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.636 Times cited 14 Open Access  
  Notes ; The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, I) is gratefully acknowledged. The authors thank D. Grolimund and C.N. Borca for assisting the mu XRF/XRD conducted experiments at MicroXAS Beamline of SLS Thanks are due to Porvair for supplying FeCrAlloy foams. ; Approved Most recent IF: 4.636; 2015 IF: 3.893  
  Call Number (up) UA @ admin @ c:irua:124616 Serial 5656  
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Author Vanmeert, F.; van der Snickt, G.; Janssens, K. pdf  doi
openurl 
  Title Plumbonacrite identified by X-ray powder diffraction tomography as a missing link during degradation of red lead in a Van Gogh painting Type A1 Journal article
  Year 2015 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 54 Issue 12 Pages 3607-3610  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Red lead, a semiconductor pigment used by artists since antiquity, is known to undergo several discoloration phenomena. These transformations are either described as darkening of the pigment caused by the formation of either plattnerite (β-PbO2) or galena (PbS) or as whitening by which red lead is converted into anglesite (PbSO4) or (hydro)cerussite (2 PbCO3⋅Pb(OH)2; PbCO3). X-ray powder diffraction tomography, a powerful analytical method that allows visualization of the internal distribution of different crystalline compounds in complex samples, was used to investigate a microscopic paint sample from a Van Gogh painting. A very rare lead mineral, plumbonacrite (3 PbCO3⋅ Pb(OH)2⋅PbO), was revealed to be present. This is the first reported occurrence of this compound in a painting dating from before the mid 20th century. It constitutes the missing link between on the one hand the photoinduced reduction of red lead and on the other hand (hydro)cerussite, and thus sheds new light on the whitening of red lead.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000351178300008 Publication Date 2015-02-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 24 Open Access  
  Notes ; The authors acknowledge L. Van der Loeff and M. Leeuwestein (Kroller-Muller Museum) for providing the paint sample. We thank Dr. J. Jaroszewicz (WUT) for performing the CT measurements. This research was carried out at the light source PETRA III at DESY, a member of the Helmholtz Association (HGF). We thank Dr. G. Falkenberg and the members of his team for their assistance in using beam line P06. We acknowledge financial support from the University of Antwerp GOA projects “XANES meets EELS” and “SOLARPaint”, as well as from BELSPO (Brussels) Project S2-ART and FWO (Brussels) project “ESRF-Dubble”. ; Approved Most recent IF: 11.994; 2015 IF: 11.261  
  Call Number (up) UA @ admin @ c:irua:124620 Serial 5774  
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Author Bertrand, L.; Schoeeder, S.; Anglos, D.; Breese, M.B.H.; Janssens, K.; Moini, M.; Simon, A. pdf  doi
openurl 
  Title Mitigation strategies for radiation damage in the analysis of ancient materials Type A1 Journal article
  Year 2015 Publication Trends in analytical chemistry Abbreviated Journal Trac-Trend Anal Chem  
  Volume 66 Issue Pages 128-145  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The study of materials in cultural heritage artifacts and micro-samples benefits from diagnostic techniques based on intense radiation sources, such as synchrotrons, ion-beam accelerators and lasers. While most of the corresponding techniques are classified as non-destructive, investigation with photons or charged particles entails a number of fundamental processes that may induce changes in materials. These changes depend on irradiation parameters, properties of materials and environmental factors. In some cases, radiation-induced damage may be detected by visual inspection. When it is not, irradiation may still lead to atomic and molecular changes resulting in immediate or delayed alteration and bias of future analyses. Here we review the effects of radiation reported on a variety of cultural heritage materials and describe the usual practice for assessing short-term and long-term effects. This review aims to raise awareness and encourage subsequent research activities to limit radiation side effects.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000352248200020 Publication Date 2014-12-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0165-9936 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.442 Times cited 35 Open Access  
  Notes ; We wish to acknowledge the support of this initiative by the International Atomic Energy Agency. We gratefully thank Professor Manfred Schreiner of the Institute of Natural Sciences and Technology in the Arts (Akademie den bildenden Kunst, Vienna, Austria) for helpful discussions and insights on this work. We thank all colleagues who accepted to have their work reproduced in this review. IPANEMA at Synchrotron SOLEIL, the Hungarian Academy of Science and IESL-FORTH were supported within the Research Infrastructure program CHARISMA of the 7th Framework Programme of the EU (Grant Agreement no. 228330). MM's contribution is based upon work supported by the National Science Foundation under Grant numbers CHE 1241672 and CHE 1440849. We thank Chris McGlinchey and Lauren Klein (Museum of Modern Art, New York, USA) for their critical rereading of the manuscript. ; Approved Most recent IF: 8.442; 2015 IF: 6.472  
  Call Number (up) UA @ admin @ c:irua:124627 Serial 5729  
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Author Vermeulen, M.; Sanyova, J.; Janssens, K. url  doi
openurl 
  Title Identification of artificial orpiment in the interior decorations of the Japanese tower in Laeken, Brussels, Belgium Type A1 Journal article
  Year 2015 Publication Heritage science Abbreviated Journal  
  Volume 3 Issue Pages Unsp 9  
  Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract In this paper, we used a multi-technique approach in order to identify the arsenic sulfide pigment used in the decorative panels of the Japanese tower in Laeken, Belgium. Our attention was drawn to this particular pigment because of its relatively good conservation state, despite its known tendency to fade over time when exposed to light. The pigment was used with different painting techniques, bound with oil and urushi in the lacquers and with an aqueous binder in the mat relief panels. In the latter case it is always applied as an underlayer mixed with ultramarine blue. This quite unusual pigment mixture also shows a good state of preservation. In this study, the orpiment used for the Japanese tower has been identified as an amorphous arsenic sulfide glass (AsxSx) with the aid of light microscopy, PLM, SEM-EDX and Raman microscopy. The pigment features different degrees of As4S4 monomer units in its structure, also known as realgar-like nano-phases. This most likely indicates different synthesis processes as the formation of these As4S4 monomers is dependent of the quenching temperature (Tq) to which the artificial pigment is exposed during the preparation phase.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000356920400001 Publication Date 2015-02-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 17 Open Access  
  Notes ; We cordially thank Gunter Grundmann for his precious advice regarding PLM and arsenic sulfide glass. 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). ; Approved Most recent IF: NA  
  Call Number (up) UA @ admin @ c:irua:124904 Serial 5649  
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Author Carniato, L.; Schoups, G.; van de Giesen, N.; Seuntjens, P.; Bastiaens, L.; Sapion, H. pdf  url
doi  openurl
  Title Highly parameterized inversion of groundwater reactive transport for a complex field site Type A1 Journal article
  Year 2015 Publication Journal of contaminant hydrology Abbreviated Journal  
  Volume 173 Issue Pages 38-58  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In this study a numerical groundwater reactive transport model of a shallow groundwater aquifer contaminated with volatile organic compounds is developed. In addition to advective-dispersive transport, the model includes contaminant release from source areas, natural attenuation, abiotic degradation by a permeable reactive barrier at the site, and dilution by infiltrating rain. Aquifer heterogeneity is parameterized using pilot points for hydraulic conductivity, specific yield and groundwater recharge. A methodology is developed and applied to estimate the large number of parameters from the limited data at the field site (groundwater levels, groundwater concentrations of multiple chemical species, point-scale measurements of soil hydraulic conductivity, and lab-scale derived information on chemical and biochemical reactions). The proposed methodology relies on pilot point parameterization of hydraulic parameters and groundwater recharge, a regularization procedure to reconcile the large number of spatially distributed model parameters with the limited field data, a step-wise approach for integrating the different data sets into the model, and high performance computing. The methodology was proven to be effective in reproducing multiple contaminant plumes and in reducing the prior parameter uncertainty of hydraulic conductivity and groundwater recharge. Our results further indicate that contaminant transport predictions are strongly affected by the choice of the groundwater recharge model and flow parameters should be identified using both head and concentration measurements. (C) 2014 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000348878900004 Publication Date 2014-12-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0169-7722 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:125290 Serial 8041  
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Author Silva, A.L.M.; Carvalho, M.L.; Janssens, K.; Veloso, J.F.C.A. pdf  doi
openurl 
  Title A large area full-field EDXRF imaging system based on a THCOBRA gaseous detector Type A1 Journal article
  Year 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 30 Issue 2 Pages 343-352  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract By taking advantage of the attractive features in terms of gain, position and energy resolution of the 2D-THCOBRA detector, a new large area Full-Field X-ray Fluorescence Imaging (FF-XRFI) system for EDXRF imaging applications was developed. The proposed FF-XRFI system has an active area of 10 x 10 cm(2) and can be used to examine macroscopic samples with a moderately good energy resolution (< 1.6 keV FWHM at 8 keV) and a suitable spatial resolution (similar to 500 mu m FWHM). This combination of characteristics allows us to record elemental distribution maps from the surface of different sample types by combining image and energy information. Two different approaches were used for X-ray optics, one based on a single pinhole and another based on a parallel multiple-hole collimator. To illustrate the system capabilities, some sample examples were imaged and studied.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000349145700003 Publication Date 2014-10-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 11 Open Access  
  Notes ; The authors thank Stijn Legrand for acquisition of the MAXRF maps shown in Fig. 15. This work was partially supported by projects CERN/FP/123604/2011 FEDER, COMPETE and FCT (Lisbon) programs. A. L. M. Silva is supported by the QREN programme Mais Centro – Programa Operacional Regional do Centro, FEDER and COMPETE, through the project Biomaterials for Regenerative Medicine (CENTRO-07-ST24-FEDER-002030). ; Approved Most recent IF: 3.379; 2015 IF: 3.466  
  Call Number (up) UA @ admin @ c:irua:125297 Serial 5452  
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Author Baken, S.; Salaets, P.; Desmet, N.; Seuntjens, P.; Vanlierde, E.; Smolders, E. doi  openurl
  Title Oxidation of iron causes removal of phosphorus and arsenic from streamwater in groundwater-fed lowland catchments Type A1 Journal article
  Year 2015 Publication Environmental science and technology Abbreviated Journal  
  Volume 49 Issue 5 Pages 2886-2894  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The fate of iron (Fe) may affect that of phosphorus (P) and arsenic (As) in natural waters. This study addresses the removal of Fe, P, and As from streams in lowland catchments fed by reduced, Fe-rich groundwater (average: 20 mg Fe L-1). The concentrations of dissolved Fe (<0.45 mu m) in streams gradually decrease with increasing hydraulic residence time (travel time) of the water in the catchment. The removal of Fe from streamwater is governed by chemical reactions and hydrological processes: the oxidation of ferrous iron (Fe(II)) and the subsequent formation of particulate Fe oxyhydroxides proceeds as the water flows through the catchment into increasingly larger streams. The Fe removal exhibits first-order kinetics with a mean half-life of 12 h, a value in line with predictions by a kinetic model for Fe(II) oxidation. The Fe concentrations in streams vary seasonally: they are higher in winter than in summer, due to shorter hydraulic residence time and lower temperature in winter. The removal of P and As is much faster than that of Fe. The average concentrations of P and As in streams (42 mu g P L-1) and 1.4 mu g As L-1) are 1 order of magnitude below those in groundwater (393 mu g P L-1 and 17 mu g As L-1). This removal is attributed to fast sequestration by oxidizing Fe when the water enters oxic environments, possibly by adsorption on Fe oxyhydroxides or by formation of ferric phosphates. The average P and As concentrations in groundwater largely exceed local environmental limits for freshwater (140 mu g P L-1 and 3 mu g As L((-1)), but in streams, they are below these limits. Naturally occurring Fe in groundwater may alleviate the environmental risk associated with P and As in the receiving streams.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000350611100040 Publication Date 2015-02-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0013-936x; 1520-5851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:125409 Serial 8354  
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Author Radepont, M.; Coquinot, Y.; Janssens, K.; Ezrati, J.-J.; de Nolf, W.; Cotte, M. url  doi
openurl 
  Title Thermodynamic and experimental study of the degradation of the red pigment mercury sulfide Type A1 Journal article
  Year 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 30 Issue 3 Pages 599-612  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The red pigment mercury sulfide, called cinnabar or vermilion, is well known to suffer from an alteration giving rise to a grey, grey-white or black color at the surface of degraded works of art. This phenomenon can dramatically affect the esthetical value of artworks. This work aims at assessing the factors (light, halides) influencing the instability of red mercury sulfide and understanding (by combining thermodynamic and experimental approaches) the chemical equilibria governing the formation and evolution of the different degradation compounds. From the thermodynamic study of the Hg-S-Cl-H2O system, it was concluded that Hg(0), Hg3S2Cl2, and Hg2Cl2 can be formed from the reaction of alpha-HgS with ClO(g). In the second part, the artificial ageing experiments presented were carried out on model samples following the conditions assessed in the first part, in order to reproduce natural ageing observed on red mercury sulfide. Similarly to degradation compounds detected on original works of art, mercury chlorine compounds such as calomel (Hg2Cl2) and corderoite (alpha-Hg3S2Cl2) were identified on the surface of alpha-HgS model samples, when exposed to light and a sodium hypochlorite solution. Sulfates were detected as well, and more particularly gypsum (CaSO4 center dot 2H(2)O) when Ca was originally present in the model sample. The relationship between color and composition is discussed as well.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000350650800005 Publication Date 2015-01-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 26 Open Access  
  Notes ; The authors gratefully acknowledge the ESRF for granting beamtime under proposal no. EC720. Michel Dubus is thanked for providing precious advices concerning ageing protocols. This research was supported by Belgian Science Policy project S2-ART (BELSPO S4DA), the GOA “SOLARPAINT” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects no. G.0C12.13, G.0704.08 and G.01769.09. ; Approved Most recent IF: 3.379; 2015 IF: 3.466  
  Call Number (up) UA @ admin @ c:irua:125474 Serial 5877  
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Author Monico, L.; Janssens, K.; Alfeld, M.; Cotte, M.; Vanmeert, F.; Ryan, C.G.; Falkenberg, G.; Howard, D.L.; Brunetti, B.G.; Miliani, C. url  doi
openurl 
  Title Full spectral XANES imaging using the Maia detector array as a new tool for the study of the alteration process of chrome yellow pigments in paintings by Vincent van Gogh Type A1 Journal article
  Year 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 30 Issue 3 Pages 613-626  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A combination of synchrotron radiation (SR) micro X-ray fluorescence (m-XRF) and XRF mode X-ray absorption near edge structure (XANES) measurements at the Cr K-edge already allowed us to establish that the photo-reduction of chromates to Cr(III) compounds is the cause of darkening of chrome yellow pigments (PbCr1-xSxO4, 0 <= x <= 0.8) in a number of paintings by Vincent van Gogh and in corresponding artificially aged paint models. A silicon drift detector (SDD) was employed to record the Cr-K XRF radiation in these X-ray micro beam-based measurements. However, in view of the limited count rate capabilities and collection solid angle of a single device, m-XRF and m-XANES employing single element SDDs (or similar) are primarily suited for collection of spectral data from individual points. Additionally, collection of XRF maps via point-by-point scanning with relatively long dwell times per point is possible but is usually confined to small areas. The development of the 384 silicon-diode array Maia XRF detector has provided valuable solutions in terms of data acquisition rate, allowing for full spectral (FS) XANES imaging in XRF mode, i.e., where spectroscopic information is available at each pixel in the scanned map. In this paper, the possibilities of SR Cr K-edge FS-XANES imaging in XRF mode using the Maia detector are examined as a new data collection strategy to study the speciation and distribution of alteration products of lead chromate-based pigments in painting materials. The results collected from two micro-samples taken from two Van Gogh paintings and an aged paint model show the possibility to perform FS-XANES imaging in practical time frames (from several minutes to a few hours) by scanning regions of sample sizes of the same order (more than 500 mm). The sensitivity and capabilities of FS-XANES imaging in providing representative chemical speciation information at the microscale (spatial resolution from similar to 2 to 0.6 mm) over the entire scanned area are demonstrated by the identification of Cr(OH) 3, Cr(III) sulfates and/or Cr(III) organometallic compounds in the corresponding phase maps, as alteration products. Comparable Cr-speciation results were obtained by performing equivalent higher spatial resolution SR m-XRF/single-point m-XANES analysis using a more conventional SDD from smaller regions of interest of each sample. Thus, large-area XRF mode FS-XANES imaging (Maia detector) is here proposed as a valuable and complementary data collection strategy in relation to “ zoomed-in” high-resolution m-XRF mapping and single-point m-XANES analysis (SDD).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000350650800006 Publication Date 2014-12-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 28 Open Access  
  Notes ; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (S2-ART project S4DA), GOA “SOLARPAINT” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) project no. G.0C12.13, G.0704.08 and G.01769.09. Support from the Italian projects PRIN (SICH Sustainability in Cultural Heritage: from diagnosis to the development of innovative system for consolidation, cleaning and protection) and PON (ITACHA Italian advanced technologies for cultural heritage applications) is also acknowledged. For the grants received thanks are expressed to ESRF (experiments EC-799, EC-1051) and DESY (experiment H-20000043). Part of this research was undertaken at the XFM beamline at the Australian Synchrotron, Victoria, Australia (experiment M4604). LM 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), Muriel Geldof (Cultural Heritage Agency of The Netherlands) and Margje Leeuwestein (Kroller-Muller Museum, Otterlo) for selecting and sharing the information on the cross-section taken from the paintings The Bedroom and Falling Leaves (Les Alyscamps). All the staff of the Van Gogh Museum and the Kroller-Muller Museum are acknowledged for their agreeable cooperation. ; Approved Most recent IF: 3.379; 2015 IF: 3.466  
  Call Number (up) UA @ admin @ c:irua:125475 Serial 5628  
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Author Nuyts, G.; Cagno, S.; Bugani, S.; Janssens, K. url  doi
openurl 
  Title Micro-XANES study on Mn browning: use of quantitative valence state maps Type A1 Journal article
  Year 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 30 Issue 3 Pages 642-650  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Historical glass, especially non-durable medieval glass, can undergo corrosion. This sometimes results in the formation of dark-coloured manganese-rich inclusions that reduce the transparency of the glass. While unaltered bulk glass contains manganese mainly present in the +II valence state, inside the inclusions Mn is present in higher valence states (+III to +IV). Two different strategies may be considered by conservators when aiming to improve the transparency. One is based on the reduction of highly oxidised black/brown compounds using mildly reducing solutions, while the other focuses more on the extraction of manganese from the inclusions by the application of chelating agents. In this paper, a method for quantitative mapping of the Mn speciation inside partially corroded historical windowpanes based on X-Ray Absorption Near-Edge Structure (XANES) spectroscopy is discussed. The calibration of such Mn valence state maps based on the combo method, a fairly reliable way to determine the oxidation state, is described in more detail. This method is used to evaluate the effect of reducing treatments on historical glass, dated to the 14th century and originating from Sidney Sussex College (Cambridge, UK), suffering from Mn browning. Glasses were examined by means of Synchrotron Radiation (SR) based microscopic X-Ray Absorption Near-Edge Structure (mXANES) spectroscopy and microscopic X-Ray Fluorescence (mXRF). X-Ray elemental distribution maps of glass cross-sections are recorded at different energies, while Mn K-edge spectra are used to convert these into Mn valence state (VS) maps. Such valence state maps will allow evaluation of a reducing treatment.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000350650800009 Publication Date 2015-02-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 8 Open Access  
  Notes ; This research was supported by the Interuniversity Attraction Poles Programme Belgian Science Policy (IUAP VI/16) and partially by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/ F50. The text also presents results of Center of Excellence AGRECHEM (Research Fund University of Antwerp, Belgium) and from the Fund for Scientific Research (FWO, Brussels, Belgium) projects no. G.0C12.13 and G.01769.09. We gratefully acknowledge ESRF for granting beamtime (experiment EC768) and the beamline scientists of ID21 for their support. The authors also want to thank Leonie Seliger of Canterbury Cathedral, UK, the Sidney Sussex College Council and Bursar Charles Larkum for providing the archaeological samples of the Franciscan Friary which are kept in store for Sidney Sussex College in Cambridge (UK). ; Approved Most recent IF: 3.379; 2015 IF: 3.466  
  Call Number (up) UA @ admin @ c:irua:125476 Serial 5719  
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Author Alfeld, M.; Janssens, K. url  doi
openurl 
  Title Strategies for processing mega-pixel X-ray fluorescence hyperspectral data: a case study on a version of Caravaggio's painting Supper at Emmaus Type A1 Journal article
  Year 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 30 Issue 3 Pages 777-789  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Technical progress in the fields of X-ray sources, optics and detectors is constantly enhancing the pace of data acquisition in XRF imaging. This enlarges the size of the hyperspectral datasets and the number of their sub-parts. This paper describes the challenges in processing large XRF datasets featuring several million pixels/spectra and the strategies developed to overcome them. During the investigation of historical paintings by scanning macro-XRF the main challenges are the correct identification of all spectral features in a dataset and its timely processing. For the identification of spectral features different approaches are discussed, i.e. the use of sum spectra, maximum pixel spectra and of chi(2)(r) maps. For the time-efficient, artefact-free evaluation of XRF imaging data, different software packages are evaluated and intercompared (AXIL, PyMCA, GeoPIXE and the in-house written datamuncher). The process of data evaluation is illustrated on a large dataset (3.4 MPixels) acquired during the investigation of a version of Caravaggio's Supper at Emmaus (143 x 199.5 cm(2)). This 17th century painting is currently the largest object entirely scanned with macroscopic XRF.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000350650800026 Publication Date 2015-02-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 67 Open Access  
  Notes ; The authors would like to thank W. de Nolf, A. Rothkirch, C. Ryan, A. Sole, B. Vekemans, P. van Espen and L. Vincze for their fruitful discussions over the years. Furthermore, the authors thank D. Swetzoff for his support. M. Alfeld was from 2009 to 2013 the recipient of a Ph.D. fellowship of the Research Foundation-Flanders (FWO, Brussels). ; Approved Most recent IF: 3.379; 2015 IF: 3.466  
  Call Number (up) UA @ admin @ c:irua:125477 Serial 5848  
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Author Vandersteen, G.; Schneidewind, U.; Anibas, C.; Schmidt, C.; Seuntjens, P.; Batelaan, O. doi  openurl
  Title Determining groundwater-surface water exchange from temperature-time series : combining a local polynomial method with a maximum likelihood estimator Type A1 Journal article
  Year 2015 Publication Water resources research Abbreviated Journal  
  Volume 51 Issue 2 Pages 922-939  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The use of temperature-time series measured in streambed sediments as input to coupled water flow and heat transport models has become standard when quantifying vertical groundwater-surface water exchange fluxes. We develop a novel methodology, called LPML, to estimate the parameters for 1-D water flow and heat transport by combining a local polynomial (LP) signal processing technique with a maximum likelihood (ML) estimator. The LP method is used to estimate the frequency response functions (FRFs) and their uncertainties between the streambed top and several locations within the streambed from measured temperature-time series data. Additionally, we obtain the analytical expression of the FRFs assuming a pure sinusoidal input. The estimated and analytical FRFs are used in an ML estimator to deduce vertical groundwater-surface water exchange flux and its uncertainty as well as information regarding model quality. The LPML method is tested and verified with the heat transport models STRIVE and VFLUX. We demonstrate that the LPML method can correctly reproduce a priori known fluxes and thermal conductivities and also show that the LPML method can estimate averaged and time-variable fluxes from periodic and nonperiodic temperature records. The LPML method allows for a fast computation of exchange fluxes as well as model and parameter uncertainties from many temperature sensors. Moreover, it can utilize a broad frequency spectrum beyond the diel signal commonly used for flux calculations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000351401200009 Publication Date 2014-12-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0043-1397; 0043-137x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:125492 Serial 7797  
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Author Silva, F.S.; Godoi, R.H.M.; Tauler, R.; de André, P.A.; Saldiva, P.H.N.; Van Grieken, R.; de Marchi, M.R.R. url  doi
openurl 
  Title Elemental composition of PM2.5 in Araraquara City (Southeast Brazil) during seasons with and without sugar cane burning Type A2 Journal article
  Year 2015 Publication Journal of environmental protection Abbreviated Journal  
  Volume 6 Issue 5 Pages 426-434  
  Keywords A2 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5), present in polluted air, has been associated with a large spectrum of health impairments, mainly because of its deep deposition into the lungs. Araraquara City (Southeast Brazil) is surrounded by sugar-cane plantations, which are burned to facilitate the harvesting; this process causes environmental pollution due to the large amounts of soot that are released into the atmosphere. In this work, the elemental composition of PM2.5 was studied in two scenarios, namely in sugar-cane harvesting (HV) and in non-harvesting (NHV) seasons. The sampling strategy included one campaign in each season. PM2.5 was collected using a dichotomous sampler (10 L·min-1, 24 h) with PTFE filters. Information concerning the bulk elemental concentration was provided by energy-dispersive X-ray fluorescence. Enrichment factor analysis indicated that S, Cl, K, Cr, Ni, Cu, Zn, As, Cd and Pb were highly enriched relative to their crustal ratios (to Al). Principal component analysis was used to get some insight about the sources of the elements. Principal component 1 (PC1) explained 30.5% of data variance. The elements that had high loading (>0.7) were: S, Cr, As, and Pb; these are associated with combustion of fossil fuels. In principal component 2 (PC2), Cl, Cu, Zn, and Cd showed high loadings; these elements are associated with biomass burning. The Ni concentration found is three times larger than the threshold of risk for lung cancer, as recommended by the World Health Organization.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2015-05-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2152-2197 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:125885 Serial 7891  
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Author Borhani, A.H.; Berghmans, H.; Trashin, S.; De Wael, K.; Fago, A.; Moens, L.; Habibi-Rezaei, M.; Dewilde, S. url  doi
openurl 
  Title Kinetic properties and heme pocket structure of two domains of the polymeric hemoglobin of Artemia in comparison with the native molecule Type A1 Journal article
  Year 2015 Publication Biochimica et biophysica acta : proteins and proteomics Abbreviated Journal Bba-Proteins Proteom  
  Volume 1854 Issue 10a Pages 1307-1316  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract In this project, we studied some physicochemical properties of two different globin domains of the polymeric hemoglobin of the brine shrimp Artemia salina and compared them with those of the native molecule. Two domains (AsHbC1D1 and AsHbC1D5) were cloned and expressed in BL21(DE3)pLysS strain of Escherichiacoli. The recombinant proteins as well as the native hemoglobin (AfHb) were purified from bacteria and frozen Artemia, respectively by standard chromatographic methods and assessed by SDS-PAGE. The heme environment of these proteins was studied by optical spectroscopy and ligand-binding kinetics (e.g. CO association and O2 binding affinity) were measured for the two recombinant proteins and the native hemoglobin. This indicates that the CO association rate for AsHbC1D1 is higher than that of AsHbC1D5 and AfHb, while the calculated P50 value for AsHbC1D1 is lower than that of AsHbC1D5 and AfHb. The geminate and bimolecular rebinding parameters indicate a significant difference between both domains. Moreover, EPR results showed that the heme pocket in AfHb is in a more closed conformation than the heme pocket in myoglobin. Finally, the reduction potential of − 0.13 V versus the standard hydrogen electrode was determined for AfHb by direct electrochemical measurements. It is about 0.06 V higher than the potential of the single domain AsHbC1D5. This work shows that each domain in the hemoglobin of Artemia has different characteristics of ligand binding.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000362307500008 Publication Date 2015-05-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1570-9639 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 2.773 Times cited Open Access  
  Notes ; This work was supported by the general grant for visiting scholar of the Ministry of Science, Research and Technology of I. R. Iran and by the University of Antwerp. ; Approved Most recent IF: 2.773; 2015 IF: 2.747  
  Call Number (up) UA @ admin @ c:irua:125909 Serial 5683  
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Author Tang, T.; Boenne, W.; Desmet, N.; Seuntjens, P.; Bronders, J.; van Griensven, A. pdf  doi
openurl 
  Title Quantification and characterization of glyphosate use and loss in a residential area Type A1 Journal article
  Year 2015 Publication The science of the total environment Abbreviated Journal  
  Volume 517 Issue Pages 207-214  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Urban runoff can be a significant source of pesticides in urban streams. However, quantification of this source has been difficult because pesticide use by urban residents (e.g., on pavements or in gardens) is often unknown, particularly at the scale of a residential catchment. Proper quantification and characterization of pesticide loss via urban runoff require sound information on the use and occurrence of pesticides at hydrologically-relevant spatial scales, involving various hydrological conditions. We conducted a monitoring study in a residential area (9.5 ha, Flanders, Belgium) to investigate the use and loss of a widely-used herbicide (glyphosate) and its major degradation product (aminomethylphosphonic acid, AMPA). The study covered 13 rainfall events over 67 days. Overall, less than 0.5% of glyphosate applied was recovered from the storm drain outflow in the catchment. Maximum detected concentrations were 6.1 mu g/L and 5.8 mu g/L for glyphosate and AMPA, respectively, both of which are below the predicted no-effect concentration for surface water proposed by the Flemish environmental agency (10 mu g/L), but are above the EU drinking water standard (0.1 mu g/L). The measured concentrations and percentage loss rates can be attributed partially to the strong sorption capacity of glyphosate and low runoff potential in the study area. However, glyphosate loss varied considerably among rainfall events and event load of glyphosate mass was mainly controlled by rainfall amount, according to further statistical analyses. To obtain urban pesticide management insights, robust tools are required to investigate the loss and occurrence of pesticides influenced by various factors, particularly the hydrological and spatial factors. (C) 2015 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000352663800020 Publication Date 2015-02-27  
  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 (up) UA @ admin @ c:irua:125992 Serial 8431  
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Author Cabal, A.; Schalm, O.; Eyskens, P.; Willems, P.; Harth, A.; van Espen, P. pdf  doi
openurl 
  Title Comparison of x-ray absorption and emission techniques for the investigation of paintings Type A1 Journal article
  Year 2015 Publication X-ray spectrometry Abbreviated Journal  
  Volume 44 Issue 3 Pages 141-148  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)  
  Abstract Four x-ray techniques: computed radiography, emission radiography, energy-resolved radiography and imaging x-ray fluorescence were compared using four mock-up panel paintings. The paintings have different stratigraphy and pigments and are representative for different historical periods. One of the paintings has a hidden underlying painting. The type of pigments used mainly influences the information obtained by both the emission and absorption measurements; high-Z white pigment and high-Z color pigments giving the best contrast. Each of the techniques revealed interesting aspects of the paintings, but none of them could reveal the hidden painting to a satisfactory level. Due to the statistical quality of the spectral data, x-ray fluorescence gives elemental images with high contrast. The radiographic images are better to reveal the internal structure. Imaging x-ray fluorescence and energy-resolved radiography measurements can be done simultaneously, and the combination has the highest potential for the study of complex multilayer paintings. Copyright (c) 2015 John Wiley & Sons, Ltd.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000353644500010 Publication Date 2015-02-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0049-8246 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:126016 Serial 7698  
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Author Alfeld, M.; Laurenze-Landsberg, C.; Denker, A.; Janssens, K.; Noble, P. pdf  doi
openurl 
  Title Neutron activation autoradiography and scanning macro-XRF of Rembrandt van Rijn's Susanna and the Elders (Gemaldegalerie Berlin) : a comparison of two methods for imaging of historical paintings with elemental contrast Type A1 Journal article
  Year 2015 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater  
  Volume 119 Issue 3 Pages 795-805  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Imaging methods with elemental contrast are of great value for the investigation of historical paintings, as they allow for study of sub-surface layers that provide insight into a painting's creation process. Two of the most important methods are neutron activation autoradiography (NAAR) and scanning macro-XRF (MA-XRF). Given the differences between these methods in the fundamental physical phenomena exploited, a theoretical comparison of their capabilities is difficult and until now a critical comparison of their use on the same painting is missing. In this paper, we present a study of Rembrandt van Rijn's painting Susanna and the Elders from the Gemaldegalerie in Berlin employing both techniques. The painting features a considerable number of overpainted features and a wide range of pigments with different elemental tracers, including earth pigments (Mn/Fe), Azurite (Cu), lead white (Pb), vermilion (Hg) and smalt (Co, As). MA-XRF can detect all elements above Si (Z = 14), suffers from few spectral overlaps and can be performed in a few tens of hours in situ, i.e. in a museum. NAAR requires the stay of the painting at a research facility for several weeks, and inter-element interferences can be difficult to resolve. Also, only a limited number of elements contribute to the acquired autoradiographs, most notably Mn, Cu, As, Co, Hg and P. However, NAAR provides a higher lateral resolution and is less hindered by absorption in covering layers, which makes it the only method capable of visualizing P in lower paint layers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000354189200001 Publication Date 2015-04-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.455 Times cited 11 Open Access  
  Notes ; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents the results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) Project Nos. G.0704.08 and G.01769.09. M. Alfeld received from 2009 to 2013 a PhD fellowship of the Research Foundation-Flanders (FWO). ; Approved Most recent IF: 1.455; 2015 IF: 1.704  
  Call Number (up) UA @ admin @ c:irua:126034 Serial 5745  
Permanent link to this record
 

 
Author Van Hoey, S.; Nopens, I.; van der Kwast, J.; Seuntjens, P. doi  openurl
  Title Dynamic identifiability analysis-based model structure evaluation considering rating curve uncertainty Type A1 Journal article
  Year 2015 Publication Journal of hydrologic engineering Abbreviated Journal  
  Volume 20 Issue 5 Pages 04014072  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract When applying hydrological models, different sources of uncertainty are present, and evaluations of model performances should take these into account to assess model outcomes correctly. Furthermore, uncertainty in the discharge observations complicates the model identification, both in terms of model structure and parameterization. In this paper, the authors compare two different lumped model structures (PDM and NAM) considering uncertainty coming from the rating curve. Limits of acceptability for the model simulations were determined based on derived uncertainty bounds of the discharge observations. The authors applied the DYNamic Identifiability Approach (DYNIA) to identify structural failure of both models and to evaluate the configuration of their structures. In general, similar model performances are observed. However, the model structures tend to behave differently in the course of time, as revealed by the DYNIA approach. Based on the analyses performed, the probability based soil storage representation of the PDM model outperforms the NAM structure. The incorporation of the observation error did not prevent the DYNIA analysis to identify potential model structural deficiencies that are limiting the representation of the seasonal variation, primarily indicated by shifting regions of parameter identifiability. As such, the proposed approach is able to indicate where deficiencies are found and model improvement is needed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000353995400002 Publication Date 2014-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1084-0699 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number (up) UA @ admin @ c:irua:126056 Serial 7829  
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Author Hamidi-Asl, E.; Dardenne, F.; Blust, R.; De Wael, K. url  doi
openurl 
  Title An improved electrochemical aptasensor for chloramphenicol detection based on aptamer incorporated gelatine Type A1 Journal article
  Year 2015 Publication Sensors Abbreviated Journal Sensors-Basel  
  Volume 15 Issue 4 Pages 7605-7618  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Because of the biocompatible properties of gelatine and the good affinity of aptamers for their targets, the combination of aptamer and gelatine type B is reported as promising for the development of biosensing devices. Here, an aptamer for chloramphenicol (CAP) is mixed with different types of gelatine and dropped on the surface of disposable gold screen printed electrodes. The signal of the CAP reduction is investigated using differential pulse voltammetry. The diagnostic performance of the sensor is described and a detection limit of 1.83 x 10(-10) M is found. The selectivity and the stability of the aptasensor are studied and compared to those of other CAP sensors described in literature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000354236100025 Publication Date 2015-03-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1424-8220 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.677 Times cited 21 Open Access  
  Notes ; Ezat Hamidi-Asl was financially supported by IOF-POC (University of Antwerp). ; Approved Most recent IF: 2.677; 2015 IF: 2.245  
  Call Number (up) UA @ admin @ c:irua:126071 Serial 5464  
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Author Pilehvar, S.; Jambrec, D.; Gebala, M.; Schuhmann, W.; De Wael, K. doi  openurl
  Title Intercalation of proflavine in ssDNA aptamers : effect on binding of the specific target chloramphenicol Type A1 Journal article
  Year 2015 Publication Electroanalysis Abbreviated Journal Electroanal  
  Volume 27 Issue 8 Pages 1836-1841  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The structural modification of ssDNA-based aptamers upon specific binding of its target molecule leads to changes of the charge-transfer resistance (Rct) of a negatively-charged free-diffusing redox probe. The aptamer adopts a structure due to self-hybridization which is stabilized using profalvine as intercalator. The pre-organized aptamer structure is used to detect chloramphenicol (CAP) requiring a substantial change of the aptamer structure indicated by a CAP concentration dependent increase in the Rct values. Pre-incubation of the aptamer-modified electrode with an intercalator allows for the modulation of the aptamer/target interaction and hence for a modulation of the CAP-dependent variation of the Rct values.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000359737500006 Publication Date 2015-06-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1040-0397 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.851 Times cited 5 Open Access  
  Notes ; D. J., M. G., W. S. are grateful for financial support to the Deutsch-Israelische Projektkooperation (DIP) in the framework of the project “Nanoengineered optoelectronics with biomaterials and bioinspired assemblies” funded by the Deutsche Forschungsgemeinschaft. S. P. and K. D. W. are thankful to UA for DOCPRO financial support. ; Approved Most recent IF: 2.851; 2015 IF: 2.138  
  Call Number (up) UA @ admin @ c:irua:126494 Serial 5666  
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Author Amiri-Aref, M.; Raoof, J.B.; Kiekens, F.; De Wael, K. pdf  doi
openurl 
  Title Mixed hemi/ad-micelles coated magnetic nanoparticles for the entrapment of hemoglobin at the surface of a screen-printed carbon electrode and its direct electrochemistry and electrocatalysis Type A1 Journal article
  Year 2015 Publication Biosensors and bioelectronics Abbreviated Journal Biosens Bioelectron  
  Volume 74 Issue Pages 518-525  
  Keywords A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract An efficient procedure for the physical entrapment of proteins within a biocompatible matrix and their immobilization on electrode surfaces is of utmost importance in the fabrication of biosensors. In this work, the magnetic entrapment of hemoglobin (Hb) at the surface of a screen-printed carbon electrode (SPCE), through mixed hemi/ad-micelles (MHAM) array of positively charged surfactant supported iron oxide magnetic nanoparticles (Mag-NPs), is reported. The Hb/MHAM@Mag-NPs biocomposite is captured at SPCE by a super magnet (Hb/MHAM@Mag-NPs/SPCE). To gain insight in the configuration of the mixed hemi/ad-micelles of CTAB at Mag-NPs, zeta-potential measurements were performed. The entrapment of Hb at MHAM@Mag-NPs was confirmed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR). Direct electron transfer of the Hb intercalated into the composite film showed a pair of well-defined quasi-reversible redox peak at formal potential of −0.255 V vs. Ag/AgCl corresponding to heme Fe(III)/Fe(II) redox couple. It shows that the MHAM@Mag-NPs composite could increase the adsorption ability for Hb, thus provides a facile direct electron transfer between the Hb and the substrate. The proposed biosensor showed excellent electrocatalytic activity to the H2O2 reduction in the wide concentration range from 5.0 to 300.0 µM obtained by amperometric measurement. The MichaelisMenten constant (Km) value of Hb at the modified electrode is 55.4 µM, showing its high affinity. Magnetic entrapment offers a promising design for fast, convenient and effective immobilization of protein within a few minutes for determination of the target molecule in low sample volume at disposable cost-effective SPCE.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000360772800071 Publication Date 2015-07-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0956-5663 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 7.78 Times cited 14 Open Access  
  Notes ; We are thankful for the BOF financial support from the University of Antwerp and Hercules financial support (SEM). ; Approved Most recent IF: 7.78; 2015 IF: 6.409  
  Call Number (up) UA @ admin @ c:irua:126535 Serial 5731  
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