Home << 1 2 3 >>
List View
 | 
Citations
 | 
Details
   web
Records
Author Van Echelpoel, R.; de Jong, M.; Daems, D.; van Espen, P.; De Wael, K.
Title Unlocking the full potential of voltammetric data analysis : a novel peak recognition approach for (bio)analytical applications Type A1 Journal article
Year 2021 Publication Talanta Abbreviated Journal Talanta
Volume 233 Issue Pages (down) 122605
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Bridging the gap between complex signal data output and clear interpretation by non-expert end-users is a major challenge many scientists face when converting their scientific technology into a real-life application. Currently, pattern recognition algorithms are the most frequently encountered signal data interpretation algorithms to close this gap, not in the least because of their straight-forward implementation via convenient software packages. Paradoxically, just because their implementation is so straight-forward, it becomes cumbersome to integrate the expert's domain-specific knowledge. In this work, a novel signal data interpretation approach is presented that uses this domain-specific knowledge as its fundament, thereby fully exploiting the unique expertise of the scientist. The new approach applies data preprocessing in an innovative way that transcends its usual purpose and is easy to translate into a software application. Multiple case studies illustrate the straight-forward application of the novel approach. Ultimately, the approach is highly suited for integration in various (bio)analytical applications that require interpretation of signal data.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000668000500108 Publication Date 2021-06-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-9140; 1873-3573 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.162 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.162
Call Number UA @ admin @ c:irua:179417 Serial 8712
Permanent link to this record
 
 
Author Baly, L.; Quesada, I.; Murray, A.S.; Martin, G.; van Espen, P.; Arteche, R.; Jain, M.
Title Modeling the charge deposition in quartz grains during natural irradiation and its influence on the optically stimulated luminescence signal Type A1 Journal article
Year 2021 Publication Radiation Measurements Abbreviated Journal Radiat Meas
Volume 142 Issue Pages (down) 106564
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The rate of charge deposition in quartz grains irradiated in natural conditions is computed by radiation transport modeling. Quartz luminescence models are modified with the addition of the resulting charge deposition term, and the influence of this process on the optically stimulated luminescence (OSL) signal is analyzed. The results indicate that the charge deposition occurring in the quartz grain during the time of residence within rock could lead to the depletion of trapped holes in the recombination centres. For the two different quartz models investigated here, complete depletion is expected to occur for rock ages between 500 Ma and 1100 Ma. It is predicted that for sedimentary quartz derived from such rocks, the OSL signal is dominated by the slow component. It was also found that the shape and saturation level of the natural sensitivity-corrected dose response curve (DRC) of quartz is affected by the charge deposition; specifically, a linear reduction of the saturation level with the age of the rock is observed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000639160300003 Publication Date 2021-03-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1350-4487 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.442 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 1.442
Call Number UA @ admin @ c:irua:178307 Serial 8265
Permanent link to this record
 
 
Author Alejo, D.; Morales, M.C.; de la Torre, J.B.; Grau, R.; Bencs, L.; Van Grieken, R.; van Espen, P.; Sosa, D.; Nuñez, V.
Title Seasonal trends of atmospheric nitrogen dioxide and sulfur dioxide over North Santa Clara, Cuba Type A1 Journal article
Year 2013 Publication Environmental monitoring and assessment Abbreviated Journal
Volume 185 Issue 7 Pages (down) 6023-6033
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Atmospheric nitrogen dioxide (NO2) and sulfur dioxide (SO2) levels were monitored simultaneously by means of Radiello passive samplers at six sites of Santa Clara city, Cuba, in the cold and the warm seasons in 2010. The dissolved ionic forms of NO2 and SO2 as nitrate and sulfite plus sulfate, respectively, were determined by means of ion chromatography. Analysis of NO2 as nitrite was also performed by UVVis spectrophotometry. For NO2, significant t tests show good agreement between the results of IC and UVVis methods. The NO2 and SO2 concentrations peaked in the cold season, while their minimum levels were experienced in the warm season. The pollutant levels do not exceed the maximum allowable limit of the Cuban Standard 39:1999, i.e., 40 μg/m3 and 50 μg/m3 for NO2 and SO2, respectively. The lowest pollutant concentrations obtained in the warm season can be attributed to an increase in their removal via precipitation (scavenging) while to the decreased traffic density and industrial emission during the summer holidays (e.g., July and August).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000319753600053 Publication Date 2012-12-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1420-2026; 1573-2967 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:107293 Serial 8501
Permanent link to this record
 
 
Author van der Snickt, G.; Dubois, H.; Sanyova, J.; Legrand, S.; Coudray, A.; Glaude, C.; Postec, M.; van Espen, P.; Janssens, K.
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 (down) 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 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
Permanent link to this record
 
 
Author Verlinden, G.; Janssens, G.; Gijbels, R.; van Espen, P.; Geuens, I.
Title Three-dimensional chemical characterization of complex silver halide microcrystals by scanning ion microprobe mass analysis Type A1 Journal article
Year 1997 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 69 Issue Pages (down) 3773-3779
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos A1997XV71200019 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 6 Open Access
Notes Approved Most recent IF: 6.32; 1997 IF: 4.743
Call Number UA @ lucian @ c:irua:16959 Serial 3647
Permanent link to this record
 
 
Author Roet, D.; van Espen, P.
Title Monte Carlo simulation of X-ray spectra from low energy electrons using optical data Type A1 Journal article
Year 2010 Publication Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms Abbreviated Journal
Volume 268 Issue 17/18 Pages (down) 2794-2800
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract An approach using optical data to simulate both the bremsstrahlung continuum and characteristic K and L X-ray lines generated by low energy electrons (cfr. electron microscopy) in solids is discussed in this paper. The necessary analytical expressions together with the data to calculate the relevant cross sections for elastic and inelastic interactions at these energies along with variance reduction techniques are given. The results of the Monte Carlo simulation are compared to experimental data measured with a JEOL 6300 electron microscope.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281498900039 Publication Date 2010-07-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-583x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:84261 Serial 8281
Permanent link to this record
 
 
Author Gregory, C.L.; Nullens, H.A.; Gijbels, R.H.; van Espen, P.J.; Geuens, I.; de Keyzer, R.
Title Automated particle analysis of populations of silver halide microcrystals by electron probe microanalysis under cryogenic conditions Type A1 Journal article
Year 1998 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 70 Issue Pages (down) 2551-2559
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000074584700047 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 12 Open Access
Notes Approved Most recent IF: 6.32; 1998 IF: 4.580
Call Number UA @ lucian @ c:irua:21308 Serial 210
Permanent link to this record
 
 
Author Kindratenko, V.V.; van Espen, P.J.M.; Treiger, B.A.; Van Grieken, R.E.
Title Fractal dimensional classification of aerosol particles by computer-controlled scanning electron microscopy Type A1 Journal article
Year 1994 Publication Environmental science and technology Abbreviated Journal
Volume 28 Issue Pages (down) 2197-2202
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1994PP82900033 Publication Date 2007-05-30
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 UA @ admin @ c:irua:9497 Serial 7983
Permanent link to this record
 
 
Author Abreu, Y.; Cruz, C.M.; van Espen, P.; Piñera, I.; Leyva, A.; Cabal, A.E.
Title Multiscale modeling of radiation damage and annealing in Si samples implanted with 57-Mn radioactive ions Type P1 Proceeding
Year 2011 Publication IEEE conference record T2 – IEEE Nuclear Science Symposium/Medical Imaging Conference (NSS/MIC)/18th, International Workshop on Room-Temperature Semiconductor X-Ray and, Gamma-Ray Detectors, OCT 23-29, 2011, Valencia, SPAIN Abbreviated Journal
Volume Issue Pages (down) 1754-1756
Keywords P1 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The radiation damage created in silicon materials by Mn-57 -> Fe-57 ion implantation has been studied and characterized by Mossbauer spectroscopy showing four main lines, assigned to: substitutional, interstitial and damaged configuration sites of the implanted ions. Nevertheless, the Mossbauer spectrum of Fe-57 in this materials remains with some ambiguous identification regarding the implantation configurations before and after annealing, specially the damaged configurations and its evolution. In the present work some possible implantation configurations are suggested and evaluated using a multiscale approach by Monte Carlo ion transport and electronic structure calculations within DFT. The proposed implantation environments were evaluated in terms of stability and the Fe-57 hyperfine parameters were calculated to establish the connections with the experimental observations. Good agreement was found between the experimental and the calculated hyperfine parameters for some configurations; suggesting which ones could be the implantation environments before and after sample annealing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000304755601202 Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-1-4673-0120-6 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:113073 Serial 8289
Permanent link to this record
 
 
Author Piñera, I.; Abreu, Y.; van Espen, P.; Diaz, A.; Leyva, A.; Cruz, C.M.
Title Radiation damage evaluation on LYSO and LuYAP materials through Dpa calculation assisted by Monte Carlo method Type P1 Proceeding
Year 2011 Publication IEEE conference record T2 – IEEE Nuclear Science Symposium/Medical Imaging Conference (NSS/MIC)/18th, International Workshop on Room-Temperature Semiconductor X-Ray and, Gamma-Ray Detectors, OCT 23-29, 2011, Valencia, SPAIN Abbreviated Journal
Volume Issue Pages (down) 1609-1611
Keywords P1 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The aim of the present work is to study the radiation damage induced in LYSO and LuYAP crystals by the gamma radiation and the secondary electrons/positrons generated. The displacements per atom (dpa) distributions inside each material were calculated following the Monte Carlo assisted Classical Method (MCCM) introduced by the authors. As gamma sources were used Sc-44, Na-22 and V-48. Also the energy of gammas from the annihilation processes (511 keV) was included in the study. This procedure allowed studying the in-depth dpa distributions inside each crystal for all four sources. It was also possible to obtain the separate contribution from each atom to the total dpa. The LYSO crystals were found to receive more damage, mainly provoked by the displacements of silicon and oxygen atoms.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000304755601169 Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-1-4673-0120-6 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:113072 Serial 8447
Permanent link to this record
 
 
Author Cabal Rodríguez, A.E.; Leyva Pernia, D.; Schalm, O.; van Espen, P.J.M.
Title Possibilities of energy-resolved X-ray radiography for the investigation of paintings Type A1 Journal article
Year 2012 Publication Analytical and bioanalytical chemistry Abbreviated Journal
Volume 402 Issue 4 Pages (down) 1471-1480
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract X-ray radiographic images of paintings often show little or no contrast. In order to increase the contrast in radiographic images we measured the X-ray spectrum of a low power X-ray tube, after passing through the painting, with a high energy-resolution SDD detector. To obtain images, the detector is collimated with a 400 mu m diameter pinhole and the painting was moved through the beam in the x and y-direction using a dwell time of a few seconds per pixel. The data obtained consists of a data cube of, typically, 200 x 200 pixels and a 512-channel X-ray spectrum for each pixel, spanning the energy range from 0 to 40 keV. Having the absorbance spectrum available for each pixel, we are able, a posteriori, to produce images by edge subtraction for any given element. In this way high contrast, element-specific, images can be obtained. Because of the high energy-resolution a much simpler edge subtraction algorithm can be applied. We also used principal-component imaging to obtain, in a more automated way, images with high contrast. Some of these images can easily be attributed to specific elements. It turns out that preprocessing of the spectral data is crucial for the success of the multivariate image processing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000299842000008 Publication Date 2011-07-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1618-2642; 1618-2650 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:96200 Serial 8394
Permanent link to this record
 
 
Author Janssens, K.; van Espen, P.; Van 't dack, L.
Title Euroanalysis 14: the European Conference on Analytical Chemistry Type Editorial
Year 2008 Publication Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem
Volume 391 Issue 4 Pages (down) 1107-1108
Keywords Editorial; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000256088700001 Publication Date 2008-05-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.431 Times cited Open Access
Notes Approved Most recent IF: 3.431; 2008 IF: 3.328
Call Number UA @ admin @ c:irua:69316 Serial 5608
Permanent link to this record
 
 
Author Schalm, O.; Cabal, A.; van Espen, P.; Laquière, N.; Storme, P.
Title Improved radiographic methods for the investigation of paintings using laboratory and synchrotron X-ray sources Type A1 Journal article
Year 2011 Publication Journal of analytical atomic spectrometry Abbreviated Journal
Volume 26 Issue 5 Pages (down) 1068-1077
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract It is generally known that radiographic inspection of 1517th century paintings can easily be done with a polychromatic X-ray source using a voltage between 20 kV and 40 kV in combination with classic X-ray films. Unfortunately, the spatial structure of numerous 19th and early 20th century paintings cannot be visualized with conventional radiography due to several reasons such as the use of lead white grounds or low absorbing pigments. Radiographic images are blurred or worse, they do not contain the picture of the painting. During the last decades, many technological innovations have been introduced in the field of radiography but their possibilities in cultural heritage have not been explored in full detail. In our investigation we used phosphor imaging plates, energy dispersive detectors and CCD-cameras in combination with synchrotron radiation and conventional X-ray tubes in order to improve the quality of radiographic images. Several promising techniques that could improve the quality of radiographs of paintings were identified.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000289731900023 Publication Date 2011-04-11
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 Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:89928 Serial 8070
Permanent link to this record
 
 
Author Treiger, B.; Bondarenko, I.; van Espen, P.; Van Grieken, R.; Adams, F.
Title Classification of mineral particles by nonlinear mapping of electron microprobe energy-dispersive X-ray spectra Type A1 Journal article
Year 1994 Publication The analyst Abbreviated Journal
Volume 119 Issue Pages (down) 971-974
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1994NR76500037 Publication Date 2004-03-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:8918 Serial 7669
Permanent link to this record
 
 
Author van Espen, P.; Van 't dack, L.; Adams, F.; Van Grieken, R.
Title Effective sample weight from scatter peaks in energy-dispersive x-ray fluorescence Type A1 Journal article
Year 1979 Publication Analytical chemistry Abbreviated Journal
Volume 51 Issue 7 Pages (down) 961-967
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1979GW66100047 Publication Date 2005-03-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:111404 Serial 7841
Permanent link to this record
 
 
Author Lemberge, P.; Deraedt, I.; Janssens, K.; van Espen, P.
Title Quantitative analysis of 16-17th century archaeological glass vessels using PLS regression of EPXMA and μ-XRF data Type A1 Journal article
Year 2000 Publication Journal of chemometrics Abbreviated Journal J Chemometr
Volume 14 Issue Pages (down) 751-763
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000090065100026 Publication Date 2002-09-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0886-9383 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.884 Times cited Open Access
Notes Approved Most recent IF: 1.884; 2000 IF: 2.081
Call Number UA @ admin @ c:irua:32405 Serial 5793
Permanent link to this record
 
 
Author Cabal, A.; Legrand, S.; Van den Bril, B.; Tote, K.; Janssens, K.; van Espen, P.
Title Study of the uniformity of aerosol filters by scanning MA-XRF Type A1 Journal article
Year 2017 Publication X-ray spectrometry T2 – 17th European Conference on X-Ray Spectrometry (EXRS), JUN 19-24, 2016, Univ Gothenburg, Univ Gothenburg, Gothenburg, SWEDEN Abbreviated Journal X-Ray Spectrom
Volume 46 Issue 5 Pages (down) 461-466
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Energy-dispersive X-ray fluorescence (XRF) is an attractive analytical method to determine the level of air pollution by heavy metals. The concentration of the filter in ng/cm(2) is obtained by direct comparison of the net characteristic line intensity of an element with that of a thin film standard. As the sampled area on the filter and the area of the standard are larger than the area analysed by the instrument, the distribution of the elements on the surface of both samples and standards have to be sufficiently uniform. If this is not the case, biased concentration estimates are obtained. Two scanning macro-XRF setups with a beam diameter of similar to 0.5 mm were used to investigate the distribution of elements in (1) commercially available (Micromatter) standards, (2) in-house quartz filter standards obtained with an aerosol generator and (3) particulatematter (PM10) collected on quartz filters by a Leckel SEQ 47/50 sampler. The uniformity of the Micromatter standards was better than 2%. At least some in-house standards showed a concave distribution with less material at the edges. The maximum bias introduced by this is less than 5%. Because of the limited sensitivity of scanning XRF compared with conventional XRF, the distribution of only a few common elements like Ca and Fe could be determined reliably in aerosol filters. The distribution of some heavy elements could only be measured in filters sampled in polluted regions. In general, the loading of particulate matter over the filters was uniform. Copyright (C) 2017 John Wiley & Sons, Ltd.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000409246400026 Publication Date 2017-03-21
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 1.298 Times cited 4 Open Access
Notes ; ; Approved Most recent IF: 1.298
Call Number UA @ admin @ c:irua:145644 Serial 5852
Permanent link to this record
 
 
Author Oleshko, V.; Kindratenko, V.; Gijbels, R.; van Espen, P.; Jacob, W.
Title Study of quasi-fractal many-particle-systems and percolation networks by zero-loss spectroscopic imaging, electron energy-loss spectroscopy and digital image analysis Type A1 Journal article
Year 1996 Publication Mikrochimica acta: supplementum Abbreviated Journal
Volume 13 Issue Pages (down) 443-451
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Chemometrics (Mitac 3)
Abstract Submicron colloidal Ag particles and nano-sized filaments forming a statistical percolation network during ''in situ'' development of double structure tabular microcrystals of AgRr(I) emulsions have been studied by electron energy-loss spectroscopy and zero-loss electron spectroscopic imaging (EELS/ZLESI). Image analysis has shown that random quasi-fractal clusters were formed in the colloid. ZLESI has been applied to characterise the morphology and defect structure of aggregated particles and filaments. Their energy-loss spectra revealed plasmon excitations and interband 4d electron transitions between 4-32 eV energy-loss. To study the cluster structure and its relation to the physical properties, fractal analysis including estimations of cluster fractal dimensions and of density autocorrelation functions has been performed. Mechanisms of fractal aggregation based on known models of diffusion limited aggregation, cluster-cluster aggregation and percolation are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Wien Editor
Language Wos A1996VT82300038 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0076-8642 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number UA @ lucian @ c:irua:16247 Serial 3332
Permanent link to this record
 
 
Author Bondarenko, I.; Treiger, B.; Van Grieken, R.; van Espen, P.
Title IDAS: a Windows based software package for cluster analysis Type A1 Journal article
Year 1996 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal
Volume 51 Issue Pages (down) 441-456
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
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 0584-8547; 1873-3565 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:14649 Serial 8050
Permanent link to this record
 
 
Author Osán, J.; de Hoog, J.; van Espen, P.; Szalóki, I.; Ro, C.-U.; Van Grieken, R.
Title Evaluation of energy-dispersive x-ray spectra of low-Z elements from electron-probe microanalysis of individual particles Type A1 Journal article
Year 2001 Publication X-ray spectrometry Abbreviated Journal
Volume 30 Issue Pages (down) 419-426
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000172347800010 Publication Date 2002-08-25
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 UA @ admin @ c:irua:36091 Serial 7939
Permanent link to this record
 
 
Author Abreu, Y.; Cruz, C.M.; van Espen, P.; Pérez, C.; Piñera, I.; Leyva, A.; Cabal, A.E.
Title Electric field gradient calculations in ZnO samples implanted with 111In(111Cd) Type A1 Journal article
Year 2012 Publication Solid state communications Abbreviated Journal
Volume 152 Issue 5 Pages (down) 399-402
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract A first-principles study of the electric field gradient (EFG) calculated for ideal and In-111(Cd-111) implanted ZnO samples is reported in the present work. The study was made for ZnO ideal hexagonal structures and supercells were introduced in order to consider the possible implantation environments. The calculation was done using the “WIEN2k” code within the density functional theory, the exchange and correlation effects were determined by the GGA approximation. Three possible In-111(Cd-111) implantation configurations were studied, one substitutional incorporation at cation site and two interstitials. The obtained EFG values for the ideal structure and the substitutional site are in good agreement with the experimental reports measured by perturbed angular correlation (PAC) and high precision nuclear magnetic resonance (NMR). Thus, the ascription of substitutional incorporation of In-111(Cd-111) probe atom at the ZnO cation site after annealing was confirmed. (C) 2011 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000301329200016 Publication Date 2011-12-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:97821 Serial 7857
Permanent link to this record
 
 
Author Maenhaut, W.; Selen, A.; van Espen, P.; Van Grieken, R.; Winchester, W.J.
Title Pixe analysis of aerosol samples collected over the atlantic-ocean from a sailboat Type A1 Journal article
Year 1981 Publication Nuclear instruments and methods Abbreviated Journal
Volume 181 Issue 1-3 Pages (down) 399-405
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract Size-fractionated aerosol samples, collected over the Atlantic Ocean, were analyzed for up to 20 elements by PIXE. Using a sailboat as sampling platform, duplicate samples were taken for two-day periods by means of battery operated 6-stage cascade impactors, positioned about 8 m above the sea surface. In the PIXE analysis of the fine particle stages (stages 3 to 5) a 5 times smaller beam size was used than for stages 1 and 2. This led to significant improvement in the detection limits for the former stages. The results from the duplicate impactor samples were normally in good agreement, indicating that the combined uncertainty of sampling and PIXE analysis was of the order of 20%. The precision of the PIXE analysis alone was investigated by rebombarding some samples six months after the first analysis. The trends with time of the fine particle sulfur and the coarse particle iron concentrations are discussed in some detail.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1981LH81100073 Publication Date 2002-11-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0029-554x; 1878-3759 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:113628 Serial 8386
Permanent link to this record
 
 
Author Alejo, ellys; Morales, M.C.; Nuñez, V.; Bencs, L.; Van Grieken, R.; van Espen, P.
Title Monitoring of tropospheric ozone in the ambient air with passive samplers Type A1 Journal article
Year 2011 Publication Microchemical journal Abbreviated Journal
Volume 99 Issue 2 Pages (down) 383-387
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Two sampling campaigns in suburban places in the north zone of Santa Clara city, Cuba, have been carried out on a weekly base with the use of Radiello passive diffusion tubes in order to monitor the tropospheric ozone (O3) levels in 2010. The first campaign was scheduled from February to April (cold season) and the second one in August and October (warm season), both of them at two sampling sites, i.e., Farm and School of Art Instructors. After aqueous extraction, the samples were analyzed by UVVIS spectrophotometry. A seasonal trend was observed with the maximum O3 concentrations in the cold season and the minimum levels in the warm season. Samples collected during the cold season showed the highest O3 levels. Higher levels were reached at the Farm site with average values of about 58 ± 12 μg/m3, which exceeded the limit of the Cuban Standard 99:1999. In the warm season, the O3 concentrations were similar for both sites, but lower than those observed in the cold season. The overall, seasonal average value was found to be 24 μg/m3. Despite the higher weekly average temperatures in August, the O3 concentrations during this month showed the lowest values of the whole sampling period, which finding is in agreement with that reported by the Meteorological Institute of Cuba. Mathematical models, based on the Cochrane-Orcutt algorithm, were fitted to the acquired data set to explain the change in the tropospheric ozone concentrations under various meteorological conditions during the two campaigns. The correlation coefficients for both the cold and the warm seasons demonstrated a strong correlation, i.e., 0.779 and 0.951, respectively. The high correlation of wind speed in the model from the first sampling campaign explains the sharp decrease in O3 concentrations at the SAI sampling site from the sixth week of sampling.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000295770700034 Publication Date 2011-06-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:93294 Serial 8277
Permanent link to this record
 
 
Author Trincavelli, J.; Montoro, S.; van Espen, P.; Van Grieken, R.
Title M\alpha/L\alpha intensity ratios for Ta, W, Pt, Au, Pb and Bi for electron energies in the 11-40 keV range Type A1 Journal article
Year 1993 Publication X-ray spectrometry Abbreviated Journal
Volume 22 Issue Pages (down) 372-376
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract Both energy- and wavelength-dispersive systems were used to obtain Malpha/Lalpha intensity ratios for Ta, W, Pt, Au, Pb and Bi at various overvoltages. A table of these ratios corrected for matrix absorption and detector efficiency is presented, in addition to an interpolatory function of Malpha/Lalpha generated ratios vs. overvoltage, for each element. In addition, three different ZAF correction models were used to predict both detected and generated ratios. Finally, experimental Mbeta/Malpha ratios measured at different overvoltages are presented for the six elements considered.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1993MB01200008 Publication Date 2005-05-28
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 UA @ admin @ c:irua:6221 Serial 8649
Permanent link to this record
 
 
Author Treiger, B.; Injuk, J.; Bondarenko, I.; van Espen, P.; Van Grieken, R.; Breitenbach, L.; Wätjen, U.
Title Non-linear mapping of microbeam proton-induced X-ray emission data for source identification of North Sea aerosols Type A1 Journal article
Year 1994 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal
Volume 49 Issue 4 Pages (down) 345-353
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1994NM41200004 Publication Date 2003-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0584-8547; 1873-3565 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:9500 Serial 8314
Permanent link to this record
 
 
Author Geuens, I.; Nys, B.; Naudts, J.; Gijbels, R.; Jacob, W.; van Espen, P.
Title The primary energy dependence of backscattered electron images up to 100 keV Type A1 Journal article
Year 1991 Publication Scanning microscopy Abbreviated Journal
Volume 5 Issue 2 Pages (down) 339-344
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Chicago, Ill. Editor
Language Wos A1991GC67000005 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0891-7035 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:709 Serial 2713
Permanent link to this record
 
 
Author Janssens, K.; Nobels, J.; van Espen, P.
Title PC-MCA : a software package for the acquisition and processing of spectral data Type A1 Journal article
Year 1988 Publication Chemometrics and intelligent laboratory systems Abbreviated Journal
Volume 3 Issue 4 Pages (down) 335-341
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1988P260100012 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-7439 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:149776 Serial 5768
Permanent link to this record
 
 
Author Vanmeert, F.; De Meyer, S.; Gestels, A.; Clerici, E.A.; Deleu, N.; Legrand, S.; Van Espen, P.; Van der Snickt, G.; Alfeld, M.; Dik, J.; Monico, L.; De Nolf, W.; Cotte, M.; Gonzalez, V.; Saverwyns, S.; Depuydt-Elbaum, L.; Janssens, K.
Title Non-invasive and non-destructive examination of artists’ pigments, paints and paintings by means of X-ray imaging methods Type H1 Book chapter
Year 2022 Publication Abbreviated Journal
Volume Issue Pages (down) 317-357
Keywords H1 Book chapter; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract Recent studies 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 fifteenth to twentieth century artists are discussed. 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 with X-ray diffraction (XRD). Microscopic XRF (μ-XRF) is a variant of the XRF method able to visualize the elemental distribution of key elements, mostly metals, on the scale from 1 μm to 100 μm present inside multi-layered micro samples taken from paintings. In the context of the characterization of artists’ pigments subjected to natural degradation, in many cases the use of methods limited to elemental analysis or imaging does not suffice to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS (microscopic X-ray absorption spectroscopy) and μ-XRD have proven themselves to be very suitable for such studies. Since microscopic investigation of a relatively limited number of minute paint samples may not yield representative information about the complete artefact they were taken from, several methods for macroscopic, non-invasive imaging have recently been developed. Combined macroscopic XRF/XRD scanning is able to provide a fairly complete overview of the inorganic pigments employed to create a work of art, to answer questions about ongoing degradation phenomena and about its authenticity. As such these newly developed non-invasive and highly specific imaging methods are of interest for many cultural heritage stakeholders.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2022-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 978-3-030-86864-2 Additional Links UA library record
Impact Factor Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:190777 Serial 7183
Permanent link to this record
 
 
Author Bondarenko, I.; Treiger, B.; Van Grieken, R.; van Espen, P.
Title IDAS: a new Windows based software for multivariate analysis of atmospheric aerosol composition data bases Type H3 Book chapter
Year 1995 Publication Abbreviated Journal
Volume Issue Pages (down) 308-315 T2 - Space and time in environmental infor
Keywords H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
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 UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:12357 Serial 8049
Permanent link to this record
 
 
Author Eltayeb, M.A.H.; van Espen, P.J.; Cafmeyer, J.; Van Grieken, R.E.; Maenhaut, W.
Title Size-differentiated composition of aerosols in Khartoum, Sudan Type A1 Journal article
Year 1992 Publication The science of the total environment Abbreviated Journal
Volume 120 Issue Pages (down) 281-299
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1992JA65200008 Publication Date 2003-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697; 1879-1026 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:2834 Serial 8543
Permanent link to this record