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Author Török, S.; Braun, T.; Van Dyck, P.; Van Grieken, R.
Title Heterogeneity effects in direct XRF analysis of traces of heavy metals preconcentrated on polyurethane foam sorbents Type A1 Journal article
Year 1986 Publication X-ray spectrometry Abbreviated Journal
Volume 15 Issue 1 Pages 7-11
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) Trace amounts of heavy metals were preconcentrated on discs of polyurethane (PU) foam loaded with ammonium diethyldithiocarbamate (DDTC), to increase the sensitivity of XRF. Since the diameter of the cavities in the open-cell PU foams reaches 30300 μm, considerable heterogeneity effects might occur, which could reduce the accuracy of the method. The possible systematic error introduced by considering the sample to be homogeneous is calculated using the Berry et al. model. The calculations show that the underestimation of the absorption correction factor when considering the sample as being homogeneous is less than 2% for high-Z elements when the sample thickness is at least 2 mm. The detection limits are also around the minima for this thickness.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1986AYN6000002 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:116488 Serial 8030
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Author Romero-Pastor, J.; Garcia-Porras, A.; Van Grieken, R.; Potgieter-Vermaak, S.; Coll-Conesa, J.; Cardell, C.
Title New insights in technology characterization of medieval Valencia glazes Type A1 Journal article
Year 2015 Publication X-ray spectrometry Abbreviated Journal
Volume 44 Issue 6 Pages 426-435
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) This study shows the first Raman microscopy (RM) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) characterization of two 14th and 15th century lead-glazed and luster ceramics from the Manises and Paterna workshops (Valencia, Spain) produced after the Aragon Christian conquest of the Iberian Peninsula (14th century). According to experts, these coetaneous ceramics were most probably involved in a process of technological transfer from the Islamic area of Southeast Spain to the Christian area of Valencia (East Spain) at the beginning of the 14th century; later on, the celebrated Manises and Paterna workshops were formed. Although these ceramics have been studied widely in terms of production technology (ceramic body, glazes and luster) using an array of diverse analytical techniques, until now, an RM study has not been carried out. This paper presents results regarding the complex chemical composition of the glaze and luster coloring agents, and the quality of color manufacturing processes, elucidating firing conditions via spectral components analysis (i.e., Q(n) for stretching/bending components) and polymerization index (Ip), emphasizing chronology and pigment technology changes between both Valencian workshops. Coloring agents identified in glazes and lusters were cobalt present in blue glazes, copper in greenish glazes, copper and cobalt in the turquoise glaze, and pyrolusite in black glazes. Tin oxyde was used as an opacifier in white glazes. Two luster manufacture recipes were recognized mainly based on copper and silver compounds. Calculated firing temperatures were up to 1000 degrees C for white glazes and up to 600 degrees C for luster and color glazes. Copyright (c) 2015 John Wiley & Sons, Ltd.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000363279600002 Publication Date 2015-03-12
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 UA @ admin @ c:irua:129445 Serial 8300
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Author Asfora, V.K.; Bueno, C.C.; de Barros, V.M.; Khoury, H.; Van Grieken, R.
Title X-ray spectrometry applied for characterization of bricks of Brazilian historical sites Type A1 Journal article
Year 2020 Publication X-Ray Spectrometry Abbreviated Journal X-Ray Spectrom
Volume Issue Pages 1-8
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) This paper presents the results of X-ray fluorescence (XRF) analysis of bricks sampled from historical places in Pernambuco, a state in the northeastern region of Brazil. In this study, twenty bricks found in historical sites were analyzed. Two bricks made in the 17th century, presumably used as ballast in ships coming from Holland, five locally manufactured bricks: one from 18th century, three from 19th century, and one from 20th century, and thirteen bricks collected from a recent Archeological investigation of Alto da Se, in the town of Olinda. Qualitative determination of the chemical elements present in the samples was undertaken using a self-assembled portable XRF system based on a compact X-ray tube and a thermoelectrically cooled Si-PIN photodiode system, both commercially available. X-ray diffraction analysis was also carried out to assess the crystalline mineral phases present in the bricks. The results showed that quartz (SiO2) is the major mineral content in all bricks. Although less expressive in the XRD patterns, mineral phases of illite, kaolinite, anorthite, and rutile are also identified. The trace element distribution patterns of the bricks, determined by the XRF technique, is dominated by Fe and, in decreasing order, by K, Ti, Ca, Mn, Zr, Rb, Sr, Cr, and Y with slight differences among them. Analyses of the chemical compositional features of the bricks, evaluated by principal component analysis of the XRF datasets, allowed the samples to be grouped into five clusters with similar chemical composition. These cluster groups were able to identify both age and manufacturing sites. Dutch bricks prepared with different geological clays compositions were defined.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000568830300001 Publication Date 2020-09-17
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 1.2 Times cited Open Access
Notes ; The authors are grateful to CNPQ (Process: 305903/2011-0 and 407458/2013-1) for providing funds to carry out the present work and for supporting a visitor professor to UFPE through the program science without frontier. The authors also thank Mr. Roberto Araujo from the Center of Advanced Studies on Integrated Environmental Protection-CECI that made available the bricks to be analyzed. ; Approved Most recent IF: 1.2; 2020 IF: 1.298
Call Number UA @ admin @ c:irua:171960 Serial 6654
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Author Cagno, S.; van der Snickt, G.; Legrand, S.; Caen, J.; Patin, M.; Meulebroeck, W.; Dirkx, Y.; Hillen, M.; Steenackers, G.; Rousaki, A.; Vandenabeele, P.; Janssens, K.
Title Comparison of four mobile, non‐invasive diagnostic techniques for differentiating glass types in historical leaded windows : MA‐XRF , UV–Vis–NIR, Raman spectroscopy and IRT Type A1 Journal article
Year 2020 Publication X-Ray Spectrometry Abbreviated Journal X-Ray Spectrom
Volume Issue Pages xrs.3185-17
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract (down) This paper critically compares the performance of four non-invasive techniques that match the accuracy, flexibility, time-efficiency, and transportability required for in situ characterization of leaded glass windows: macroscopic X-ray fluorescence imaging (MA-XRF), UV-Vis-NIR, Raman spectroscopy, and infrared thermography (IRT). In order to compare the techniques on equal grounds, all techniques were tested independently of each other by separate research groups on the same historical leaded window tentatively dated to the 17th century, without prior knowledge. The aim was to assess the ability of these techniques to document the conservation history of the window by classifying and grouping the colorless glass panes, based on differences in composition. IRT, MA-XRF and UV-Vis-NIR spectroscopy positively distinguished at least two glass groups, with MA-XRF providing the most detailed chemical information. In particular, based on the ratio between the network modifier (K) and network stabilizer (Ca) and on the level of colorants and decolorizers (Fe, Mn, As), the number of plausible glass families could be strongly reduced. In addition, UV-Vis-NIR detected cobalt at ppm level and gave more specific information on the chromophore Fe2+/Fe(3+)ratio. Raman spectroscopy was hampered by fluorescence caused by the metal ions of the decolorizer in most of the panes, but nevertheless identified one group as HLLA.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000561869600001 Publication Date 2020-08-24
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 1.2 Times cited Open Access
Notes ; Belgian Federal Science Policy Office, Grant/Award Number: BR/175/A3/FENESTRA; Fonds Wetenschappelijk Onderzoek, Grant/Award Number: 12X1919N; Baillet-Latour Fund ; Approved Most recent IF: 1.2; 2020 IF: 1.298
Call Number UA @ admin @ c:irua:170972 Serial 6473
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Author Ozen, S.A.; Ozkalayci, F.; Cevik, U.; Van Grieken, R.
Title Investigation of heavy metal distributions along 15m soil profiles using EDXRF, XRD, SEM-EDX, and ICP-MS techniques Type A1 Journal article
Year 2018 Publication X-ray spectrometry Abbreviated Journal
Volume 47 Issue 3 Pages 231-241
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) The research of soil contamination by heavy metal is an important field due to its environmental and health implications. The goal was to study the elemental mobility as a function of depth. For this reason, the distribution of heavy metals (V, Cr, Co, Ni, Cu, Zn, As, Sn, and Pb) was investigated along soil profiles up to a depth of 15m at 9 sampling sites in the Nilufer industrial district (Bursa, Turkey). Elemental analyses were done with the Epsilon 5 energy dispersive X-ray fluorescence and inductively coupled plasma mass spectrometry equipment. Particle analysis was performed with a JEOL scanning electron microscope equipped with a Si(Li) X-ray detector. The crystallographic compositions of oxide compounds in soil samples were identified by a Rigaku X-ray diffraction instrument. Different parameters such as the soil's chemical (mineralogical structure, pH, and electrical conductivity) and physical properties (the number of blows, the stiffness index, the liquidity index, the plasticity index, and the water content) were analyzed. To assess the mobility of the heavy metals, diffusion (D) and convection coefficients (?) were calculated with the finite difference method. Convection was determined to dominate the studied region. In addition, the mobility coefficient was determined for each metal. High mobilities were determined for Zn and V, moderate mobilities for Cr, Ni, Cu, and As, and low mobilities were determined for Co and Pb. The results revealed that elements had reached depths of up to 15m, causing irreversible soil contamination that may lead to environmental health issues.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430188700005 Publication Date 2018-03-09
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:150722 Serial 8123
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Author Amato, S.R.; Burnstock, A.; Cross, M.; Janssens, K.; Rosi, F.; Cartechini, L.; Fontana, R.; Dal Fovo, A.; Paolantoni, M.; Grazia, C.; Romani, A.; Michelin, A.; Andraud, C.; Tournie, A.; Dik, J.
Title Interpreting technical evidence from spectral imaging of paintings by Edouard Manet in the Courtauld Gallery Type A1 Journal article
Year 2019 Publication X-ray spectrometry T2 – MA-XRF Workshop on Developments and Applications of Macro-XRF in, Conservation, Art, and Archeology, SEP 24-25, 2017, Trieste, ITALY Abbreviated Journal X-Ray Spectrom
Volume 48 Issue 4 Pages 282-292
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) The paintings by edouard Manet in The Courtauld Gallery Dejeuner sur l'herbe (1863-68), Marguerite de Conflans en Toilette de Bal (1870-1880), Banks of the Seine at Argenteuil (1874), and A Bar at the Folies-Bergere (1882) were investigated for the first time using a range of non-invasive in situ analyses. The aims of the study were to investigate the painting techniques and materials used for this group of works and to critically evaluate the technical evidence derived from the integrated use of imaging techniques and portable spectroscopic methods in this context. The paintings were investigated by means of macro X-ray fluorescence (MA-XRF), reflection spectral imaging, portable UV-Vis-NIR spectroscopy, portable Raman spectroscopy, and reflection FTIR. MA-XRF and reflection spectral imaging allowed visualising elements in the compositions that were not visible using traditional methods of technical study. For example, MA-XRF analysis of Dejeuner sur l'herbe revealed elements of the development of the composition that provided new evidence to consider its relationship to other versions of the composition. The study also highlighted questions about the interpretation of elemental distribution maps and spectral images that did not correspond to the reworking visible in X-radiographs. For example, in A Bar at the Folies-Bergere Manet made numerous changes during painting, which were not clearly visualised with any of the techniques used. The research has wider implications for the study of Impressionist paintings, as the results will support technical studies of works by other artists of the period who used similar materials and painting methods.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000472210700005 Publication Date 2018-01-23
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 Open Access
Notes ; Financial support by the Access to Research Infrastructures activity in the Horizon 2020 Programme of the EU (IPERION CH Grant agreement 654028) is gratefully acknowledged. ; Approved Most recent IF: 1.298
Call Number UA @ admin @ c:irua:161296 Serial 5670
Permanent link to this record
 
 
Author Török, S.; Van Dyck, P.; Van Grieken, R.
Title Heterogeneity effects in direct X-ray fluorescence analysis of hair Type A1 Journal article
Year 1984 Publication X-ray spectrometry Abbreviated Journal
Volume 13 Issue 1 Pages 27-32
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) The methodology of direct hair analysis by energy-dispersive x-ray fluorescence was studied. The effect on the XRF result of having a non-homogeneous radial distribution of the analyte in a single hair strand and the macroscopic effects in a bundle of hairs were calculated to evaluate possible systematic errors. The detection limits were mapped as a function of the target thickness and surface fraction. It appeared that a 10 mg cm−2 sample thickness, i. e. a target with about four layers of hair strands, is recommended. The standard deviation of this simple direct analytical method is 619% for some important elements. Discrepancies with neutron activation analysis had a mean value of around 15%. About twelve elements can be determined simultaneously on a routine basis.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1984SB70200004 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:116485 Serial 8029
Permanent link to this record
 
 
Author Godoi, R.H.M.; Potgieter-Vermaak, S.; Godoi, A.F.L.; Stranger, M.; Van Grieken, R.
Title Assessment of aerosol particles within the Rubens' House Museum in Antwerp, Belgium Type A1 Journal article
Year 2008 Publication X-ray spectrometry Abbreviated Journal
Volume 37 Issue 4 Pages 298-303
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) The majority of researchers, conservators and curators recognise that atmospheric pollution is one of the major threats to works of art. In principle, all atmospheric particles, when deposited onto art objects can be considered harmful because of their potential in causing deterioration. Moreover, under certain conditions, particulate matter can induce and intensify surface damage, particularly because of its potential to serve as centre for moisture condensation and adsorbent of gaseous pollutants. To investigate the potential harm that these particles can cause, comprehensive characterisation of the particulate matter is necessary. Particulate matter was collected at the Rubens' House Museum in Antwerp, Belgium, where a unique exhibit of the paintings and living quarters of Peter Paul Rubens (1577-1640) are seen. Size segregated aerosol samples were collected for analyses of bulk and single particle elemental and molecular compositions. They were analysed by electron probe micro-analysis, utilising facilities for low-Z element determination, and by energy-dispersive x-ray fluorescence, to investigate the elemental composition of individual particles and bulk samples, and by micro Raman spectrometry, to elucidate the molecular composition. Results are interpreted separately and as a whole with the specific aim of identifying compounds that could contribute to the chemical reactions taking place on the surfaces of artefacts and which could potentially cause degradation of the objects.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000258670600004 Publication Date 2008-03-10
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:69494 Serial 7499
Permanent link to this record
 
 
Author Čevik, U.; Koz, B.; Makarovska, Y.
Title Heavy metal analysis around Iskenderun Bay in Turkey Type A1 Journal article
Year 2010 Publication X-ray spectrometry Abbreviated Journal
Volume 39 Issue 3 Pages 202-207
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) The heavy metal analysis around Iskenderun Bay in Turkey was carried out using mosses, soils, mussels, and sediments. This region is one of the most industrial areas of Turkey, including iron-steel plants, beverage, liquefied petroleum gas (LPG) plants, and oil transfer docks. Energy dispersive X-ray fluorescence spectrometry (Epsilon 5, PANalytical, Almelo, The Netherlands) was used to analyze all samples. V, Cr, Mn, Fe, Ni, Cu, Zn, As, and Pb elements were observed in all samples studied. Although Ce was detected in some mosses and soils, Sn was detected only in some moss samples. Pb concentrations in the moss samples are higher than the soil, the mussel, and the sediment samples. This can be attributed to the mosses that absorb heavy metals such as Pb easily from the air. As the aim of this study was to analyze heavy metals, the evaluation of these elements with their potential hazards for ecology and humans is briefly discussed
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000277637400006 Publication Date 2010-03-29
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:82678 Serial 8020
Permanent link to this record
 
 
Author Storms, H.M.; Janssens, K.H.; Török, S.B.; Van Grieken, R.E.
Title Evaluation of the ArmstrongBuseck correction for automated electron probe X-ray microanalysis of particles Type A1 Journal article
Year 1989 Publication X-ray spectrometry Abbreviated Journal
Volume 18 Issue 2 Pages 45-52
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) The ArmstrongBuseck correction for absorption effects in electron probe x-ray microanalysis of particles considers seven specific particle shapes, and for these geometries exact correction equations are used. This procedure implies that the analyst has to associate the particle to be analysed with a certain particle type; an arbitrary relative thickness is sometimes assumed. A theoretical study was made of this absorption correction as a function of the particle composition, type and thickness for micrometre-sized particles. It appears that a correct choice of the particle type is critical. However, when the analytical results are normalized to 100%, the differences between the models are much less pronounced, and it is justified to assume a spherical model in all cases.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1989U261400001 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:116489 Serial 5616
Permanent link to this record
 
 
Author Van Dyck, P.; Van Grieken, R.
Title Automated matrix-correction of line ratios in energy-dispersive x-ray fluorescence spectrum deconvolution Type A1 Journal article
Year 1983 Publication X-ray spectrometry Abbreviated Journal
Volume 12 Issue 3 Pages 111-114
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) Most computer XRF-spectrum deconvolution routines make use of fixed intensity ratios for the lines from one element. The magnitude of the error that fixed ratios imply has been quantitatively evaluated for samples with a varible thickness or matrix. A procedure for routinely adapting the line ratios according to the matrix effect in every sample (by making use of the matrix information present in the scatter peaks) enhances the accuracy of the spectrum evaluation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1983RA69700004 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
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:116484 Serial 7539
Permanent link to this record
 
 
Author Markowicz, A.; Van Dyck, P.; Van Grieken, R.
Title Radiometric diameter concept and exact intensities for spherical particles in x-ray fluorescence analysis Type A1 Journal article
Year 1980 Publication X-ray spectrometry Abbreviated Journal
Volume 9 Issue 2 Pages 52-56
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) In X-ray fluorescence analysis the concept of radiometric diameter, d, is often introduced in considerations of the fluorescent intensity from a particulate sample. It represents the mean geometric path of the X-rays through one particle and is usually simply taken to be equal to the volume-to-area ratio of the particle. The effective radiometric path is, however, itself dependent on geometry and absorption effects. Rigorous calculations of the fluorescent intensity from a particle in the π and π/2 geometries were carried out to evaluate the errors involved. It appears that, for π geometry, the discrepancy between these exact results and the intensity calculated via the use of d does not exceed 5.2%. For the π/2 geometry, the errors are much larger and can amount to 50% in realistic cases of X-ray fluorescence analysis. These conclusions are also applicable to monolayers. The effective radiometric diameter approaches d only when absorption effects become negligible, but is smaller in other cases.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1980JN16500003 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:116482 Serial 8451
Permanent link to this record
 
 
Author van der Linden, V.; Schalm, O.; Houbraken, J.; Thomas, M.; Meesdom, E.; Devos, A.; van Dooren, R.; Nieuwdorp, H.; Janssen, E.; Janssens, K.
Title Chemical analysis of 16th to 19th century Limoges School painted enamel objects in three museums of the Low Countries Type A1 Journal article
Year 2010 Publication X-ray spectrometry Abbreviated Journal X-Ray Spectrom
Volume 39 Issue 2 Pages 112-121
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) In this study, the results of analysing of a series of 16th-19th century painted enamel objects of the Limoges School currently in collections in three Dutch and Flemish museums by means of portable and micro x-ray fluorescence analysis (PXRF and µ-XRF) and electron probe micro analysis (EPMA) are presented. The aim of the investigation was the authentication of specific pieces. Therefore, the glass compositions as well as the (glass) colouring agents used by the Limoges' artists were studied as a function of the age of the objects. Due to the evolution of these properties, it is possible to approximately date these objects based on their chemical composition. The complete émail peint collection of the Museum Boijmans-Van Beuningen (Rotterdam, The Netherlands), consisting of 20 émail peint plaques, was analysed with µ-XRF. Quantitative information was obtained by EPMA analysis of 15 enamel fragments of objects from museum and private collections in the Low Countries. PXRF analyses were performed on the painted enamel collection of the Antwerp Vleeshuis Museum (13 objects) and the Mayer van den Bergh Museum (4 objects) and on a set of 18 plaques that were donated to the Boijmans-Van Beuningen Museum by a private collector. The results obtained by means of EPMA, µ-XRF and PXRF proved to be useful in the discrimination of 16th century painted enamel objects from those of the19th century. From a total of 70 objects examined, 2 objects (OM964A and OM993) featured a chemical signature that deviated from the published literature composition and pigment use consistent with its presumed period of manufacture.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000275959400007 Publication Date 2009-08-11
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 8 Open Access
Notes ; ; Approved Most recent IF: 1.298; 2010 IF: 1.661
Call Number UA @ admin @ c:irua:82325 Serial 5509
Permanent link to this record
 
 
Author van der Snickt, G.; Janssens, K.; Schalm, O.; Aibéo, C.; Kloust, H.; Alfeld, M.
Title James Ensor's pigment use: artistic and material evolution studied by means of portable X-ray fluorescence spectrometry Type A1 Journal article
Year 2010 Publication X-ray spectrometry Abbreviated Journal X-Ray Spectrom
Volume 39 Issue 2 Pages 103-111
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) In this paper, portable X-ray fluorescence spectrometry (PXRF) was employed as a screening tool for determining and comparing the pigment use in a large series of paintings by the Belgian artist James Ensor (1860-1949). Benefits and drawbacks of PXRF as a method, and the instrument employed, are discussed from a practical, conservation and instrumental perspective. Regardless of several restrictions due to the set-up and/or the analytical method, it appeared feasible to document the evolution with time in Ensor's use of inorganic pigments and to correlate this technical evolution with stylistic developments, Nevertheless, it became clear that a full identification of all materials present can only be done by means of the analysis of (cross-sectioned) samples.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000275959400006 Publication Date 2009-12-15
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 25 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The staff of the different museums and private institutions is acknowledged for rendering their assistance to this research, i.e. by making all paintings available for analysis and authorising the publication of the images in this article. Therefore, a word of gratitude to Paul Huvenne, Yolande Deckers, Herwig Todts, Stef Antonissen, Gwen Borms and Lizet Klaassen of the Koninklijk Museum voor Schone Kunsten Antwerpen (KMSKA), Luuk Van der Loeff of the Kroller-Muller Museum in Otterlo and Mireille Engel, Barbara De Jong of the Musea aan Zee (MuZee), Patricia Jaspers of the Dexia bank, Hildegard Van de Velde of the KBC bank and Frederik Leen of the Koninklijke Musea voor Schone Kunsten van Belgie (KMSKB). Special thanks to Xavier Tricot and the other members of the Ensor committee for their valuable feedback. ; Approved Most recent IF: 1.298; 2010 IF: 1.661
Call Number UA @ admin @ c:irua:82324 Serial 5680
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Author Cabal, A.; Schalm, O.; Eyskens, P.; Willems, P.; Harth, A.; van Espen, P.
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 (down) 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 UA @ admin @ c:irua:126016 Serial 7698
Permanent link to this record
 
 
Author Van Grieken, R.E.; Adams, F.C.
Title Folding of aerosol loaded filters during X-ray fluorescence analysis Type A1 Journal article
Year 1976 Publication X-ray spectrometry Abbreviated Journal
Volume 5 Issue 2 Pages 61-67
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) Folding aerosol loaded filters in two with the loaded side inwards during the X-ray analysis not only reduces possible filter heterogeneity effects and improves sample protection, but also increases the sensitivity and renders filter paper absorption corrections simple and more accurate in many instances. It is shown that folding an aerosol loaded Whatman filter paper during Kα X-rays counting leads to an increased sensitivity for all elements up from calcium, scandium or titanium (depending on the sensitivity definition and on the aerosol load) and for all elements up from phosphorus, sulphur or chlorine in the case of the Nuclepore filter. Although the absorption by the filter, into which the aerosol penetrates to some extent, is always more important in the sandwich than in the usual geometry, the dependence of the absorption correction on the usually unknown average deposition depth is less pronounced. Assuming all the aerosol material to be collected at the very surface of the filter and hence being present in the centre of the sandwich to be analysed, leads to an extremely simple filter paper absorption correction which is less prone to uncertainties than more sophisticated corrections in the usual geometry requiring additional measurements. This is the case for all elements up from potassium on Whatman filters and up from phosphorus on Nuclepore filters.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1976BM95300002 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:116480 Serial 7976
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Author Van Dyck, P.; Markowicz, A.; Van Grieken, R.
Title Influence of sample thickness, excitation energy and geometry on particle size effects in XRF Type A1 Journal article
Year 1985 Publication X-ray spectrometry Abbreviated Journal
Volume 14 Issue 4 Pages 183-187
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) Expressions are presented for calculating the matrix effect and the pure particle size effect in the XRF analysis of particulate samples with a discrete particle size. The equations are based on the absorption-weighted radiometric diameter concept. Two excitationdetection geometries are considered, with the angles between the sample plane and both the incident and emerging radiation being either 90° (π geometry) or 45° (π/2 geometry). Calculations were made for different sample loadings and exciting radiation energies. The influence of these parameters on the matrix and pure particle size effects is shown. From the results, it is possible to predict the performances of alternative experimental correction procedures for the particle size effect, involving dual measurements at different excitation energies or in different excitationdetection geometries.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1985ATB6100007 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:116486 Serial 8097
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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 461-466
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) 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
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Author Arana, A.; Loureiro, A.L.; Barbosa, H.M.J.; Van Grieken, R.; Artaxo, P.
Title Optimized energy dispersive X-ray fluorescence analysis of atmospheric aerosols collected at pristine and perturbed Amazon Basin sites Type A1 Journal article
Year 2014 Publication X-ray spectrometry Abbreviated Journal
Volume 43 Issue 4 Pages 228-237
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) Elemental composition of aerosols is important to source apportionment studies and to understand atmospheric processes that influence aerosol composition. Energy dispersive X-ray fluorescence spectroscopy was applied for measuring the elemental composition of Amazonian atmospheric aerosols. The instrument used was a spectrometer Epsilon 5, PANalytical B. V., with tridimensional geometry that reduces the background signal with a polarized X-ray detection. The measurement conditions were optimized for low-Z elements, e. g. Mg, Al, Si, that are present at very low concentrations in the Amazon. From Na to K, our detection limits are about 50% to 75% lower than previously published results for similar instrument. Calibration was performed using Micromatter standards, except for P whose standard was produced by nebulization of an aqueous solution of KH2PO4 at our laboratory. The multi-element reference material National Institute of Standards and Technology-2783 (air particulate filter) was used for evaluating the accuracy of the calibration procedure of the 22 elements in our standard analysis routine, and the uncertainty associated with calibration procedures was evaluated. The overall performance of the instrument and validation of our measurements were assessed by comparison with results obtained from parallel analysis using particle-induced X-ray emission and another Epsilon 5 spectrometer. The elemental composition in 660 samples collected at a pristine site in the Amazon Basin and of 1416 samples collected at a site perturbed by land use change was determined. Our measurements show trace elements associated with biogenic aerosols, soil dust, biomass burning, and sea-salt, even for the very low concentrations as observed in Amazonia. Copyright (C) 2014 John Wiley & Sons, Ltd.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000337724600006 Publication Date 2014-06-09
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:118419 Serial 8342
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Author Sauter, L.; Van der Ben, D.; Van Grieken, R.
Title Trace analysis of estuarine brown algae by energy-dispersive X-ray fluorescence Type A1 Journal article
Year 1979 Publication X-ray spectrometry Abbreviated Journal
Volume 8 Issue 4 Pages 159-163
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) Brown algae, which are good indicators for estuarine metal pollution, can advantageously be analysed by energy-dispersive X-ray fluorescence. The use of thin film samples and samples of intermediate thickness has several advantages over the conventional thick pellet procedure. A quite homogeneous thin target is prepared by suspending 15 mg of dried and ground seaweed powder in bi-distilled water and evaporating the slurry on a 10 cm2 Mylar foil held in a Teflon ring. The effective sample weight in the beam is calculated by a procedure based on the scatter peaks in the spectrum. Sensitivities are typically in the 215 ppm range. The coefficient of variation per analysis averaged over ten elements amounts to 10%. The natural concentration variation in seaweed specimens at one location is 13%. Samples from locations in the more polluted western Scheldt estuary yield significantly higher values for several elements, relative to the eastern Scheldt sites. Possible trace element variations between the top and base of plants, and between different seaweed specimens and sampling seasons, are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1979JC63700003 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:116481 Serial 8687
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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 372-376
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract (down) 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 Muia, L.M.; Van Grieken, R.
Title Theoretical evaluation of the effective alpha and De Jongh approaches in X-ray fluorescence analysis of geological materials in borax glass beads Type A1 Journal article
Year 1989 Publication X-ray spectrometry Abbreviated Journal
Volume 18 Issue 6 Pages 259-262
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) An evaluation of the accuracy and suitability of the LachanceTraill algorithm using effective α-coefficients, and the De Jongh α approach for x-ray fluorescence analysis of borax glass beads prepared from geological material was performed. By using theoretical α-coefficients obtained from the same standard and calculated elemental intensities, the two algorithms were compared under identical conditions. When only the monitor standard is used, the LachanceTrail1 approach is found to be inferior to the De Jongh basic α method. If multi-standard calibration is performed for both approaches, the accuracies are almost identical and no significant difference is found in the results. The LachanceTraill algorithm has the advantage of being easier to implement on a minicomputer and, when used without standards, it is found to give results within a few percent of the true values, which is a useful indicator in the choice of appropriate standards for more accurate analytical work.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1989CE70800002 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:116490 Serial 8660
Permanent link to this record
 
 
Author Muia, L.M.; Van Grieken, R.
Title Use of theoretical accurate binary influence coefficients with Tertian's equation in X-ray fluorescence analysis of silicate rocks in borax glass beads Type A1 Journal article
Year 1990 Publication X-ray spectrometry Abbreviated Journal
Volume 19 Issue 3 Pages 141-144
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) A study of the suitability of the Tertian algorithm using new accurate binary influence coefficients and a comparison standard for x-ray fluorescence analysis of geological materials prepared as borax glass beads was performed. The algorithm was found to give satisfactory results for the analysis of four major components in geological materials. Even in the worst case, when there is a factor of 20 difference in the concentration in the specimen and a comparison standard, the algorithm gives results which differ from the true results by a factor of about 2. This makes the algorithm attractive as a diagnostic tool in analyses of unknown specimens and in the identification of appropriate standards. The binary coefficients are easily calculated so that the algorithm can be implemented on a minicomputer.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1990DJ47800009 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:116492 Serial 8725
Permanent link to this record
 
 
Author Markowicz, A.; Storms, H.; Van Grieken, R.
Title A simple absorption correction for electron probe X-ray microanalysis of bulk samples Type A1 Journal article
Year 1986 Publication X-ray spectrometry Abbreviated Journal
Volume 15 Issue 2 Pages 115-119
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) A simple procedure is proposed for the calculation of the absorption correction factor in electron-probe x-ray microanalysis. It is based on the concept of an effective depth of x-ray production, assuming a rectangular depth distribution function for x-ray generation. This effective x-ray production depth is expressed as a fraction of the x-ray excitation depth given by Whelan's expression. Adequate values for this fraction are presented. Two versions are considered. In the first the effective x-ray production is a function of both the characteristic x-ray energy and the atomic numbers of the matrix elements, whereas in the second one, which is indicated for routine use, the energy dependence is neglected. Calculations pointed to satisfactory results, even for low x-ray energies and high overvoltages.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1986C017300007 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:113872 Serial 8524
Permanent link to this record
 
 
Author Araujo, M.F.; van Espen, P.; Van Grieken, R.
Title Determination of sample thickness via scattered radiation in X-ray fluorescence spectrometry with filtered continuum excitation Type A1 Journal article
Year 1990 Publication X-ray spectrometry Abbreviated Journal
Volume 19 Issue 1 Pages 29-33
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract (down) A semi-empirical approach is described for determining the mass per unit area of a sample being analysed. The method can be used to estimate the concentration of minor and trace elements in matrices containing a substantial amount of light elements. The procedure utilizes the coherently and incoherently scattered radiation induced in the sample by the filtered continuum radiation of a rhodium x-ray tube. The relationship between the intensity of the scattered radiation per unit mass and the average atomic number of the sample is established via calibration graphs, which can be applied for different x-ray tube voltages and for different primary beam filters. The overall procedure was validated by the analysis of several geological standards, deposited as thin slurries of unknown thickness either on Mylar foil or on Nuclepore filters.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1990CU24700005 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:116491 Serial 7787
Permanent link to this record
 
 
Author Markowicz, A.; Storms, H.; Van Grieken, R.
Title Evaluation of an equation for bremsstrahlung background in electron-probe X-ray microanalysis of composite samples Type A1 Journal article
Year 1986 Publication X-ray spectrometry Abbreviated Journal
Volume 15 Issue 2 Pages 131-133
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) A new equation for predicting the generated bremsstrahlung background intensity in electron-probe x-ray microanalysis has been verified experimentally. This equation is applicable to all bulk composite specimens and reduces to Kramers' equation for pure elements only. The experimental verification has been carried out for Al2O3, Fe2O3 and ZrO2 with radiation energies from 4.2 to 14.8 keV. The predicted bremsstrahlung intensities are in good agreement with the experimental data.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1986C017300009 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:113873 Serial 7937
Permanent link to this record
 
 
Author Van Dyck, P.; Török, S.; Van Grieken, R.
Title Monte Carlo simulation of backscattered peaks in secondary target energy-dispersive X-ray spectra Type A1 Journal article
Year 1986 Publication X-ray spectrometry Abbreviated Journal
Volume 15 Issue 4 Pages 231-238
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) A Monte Carlo simulation has been developed to describe the incoherent and coherent scatter processes for the complex geometry of a secondary target energy-dispersive x-ray fluorescence system. Photons are followed from the x-ray tube anode until the detection of scattered secondary target photons in the active Si layer of the detector. The program quantitatively shows the broadening of the incoherent scatter peak with increasing atomic number, and it models the incoherent peak shape adequately. The incoherent-to-coherent scatter intensity ratios obtained differ by 1030% from the theoretical values, while their dependence on the sample atomic number corresponds to that expected from theory.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1986E535600001 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:113612 Serial 8280
Permanent link to this record
 
 
Author Van Dyck, P.; Markowicz, A.; Van Grieken, R.
Title Automatic absorption correction in x-ray fluorescence analysis of intermediate thickness samples using a dual external reference signal Type A1 Journal article
Year 1980 Publication X-ray spectrometry Abbreviated Journal
Volume 9 Issue 2 Pages 70-76
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) A method has been investigated which allows calculations from the X-ray fluorescence spectra of the absorption coefficients at any energy for any sample, without any additional measurement. Use is made of the ratio of the characteristic X-ray signals from a Zr wire positioned in front of the sample and from a Pd foil placed behind the sample, both in a fixed geometry. From the experimentally measured absorption coefficient at the Pd L energy (2.9 keV), the coefficients for higher energies are calculated. By the use of an iterative computer routine in which corrections for the enhancement of the Pd foil by the sample are also included, an accuracy of 2% or better on the absorption coefficient determination can be reached for homogenous samples in one measurement. Grain-size and heterogeneity effects induce inaccuracies on the absorption coefficient determinations which might well reach 20% for particulate samples like intermediate thickness deposits of geological materials. This approach thus has the same limitations as the classical transmission method for such heterogeneous samples.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1980JN16500007 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:116483 Serial 7541
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Author Vanmeert, F.; Mudronja, D.; Fazinic, S.; Janssens, K.; Tibljas, D.
Title Semi-quantitative analysis of the formation of a calcium oxalate protective layer for monumental limestone using combined micro-XRF and micro-XRPD Type A1 Journal article
Year 2013 Publication X-ray spectrometry Abbreviated Journal X-Ray Spectrom
Volume 42 Issue 4 Pages 256-261
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) A current method for the protection of cretaceous limestone present in various monuments consists of performing a passivating treatment with ammonium oxalate (AmOx). A calcium oxalate protective layer is formed on the surface and enhances the acid resistance of the stone. The in-depth formation of the calcium oxalate layer was investigated on cross sections by using combined micro X-ray fluorescence and micro X-ray powder diffraction (mu XRF/mu XRPD). XRPD showed the presence of both whewellite and weddellite in the calcite stone matrix. A correction was made for sample misalignment, which was visible in both the fluorescence and the diffraction line measurements. A semi-quantitative analysis was performed on the basis of Klug's equation for a two-phase mixture (the presence of weddellite was neglected) without the need for a known reference sample. By assuming two extreme compositions for a reference weight fraction (1 and 99wt%), it was possible to obtain whewellite concentration profiles, which can be used for comparing the effectiveness of different methods for the application of AmOx to the stone surface and the effect of treatment time and AmOx concentration used. It is shown that for the relative amounts of whewellite formed, the differences due to the assumed weight fractions are smaller than the errors due to sample heterogeneity and preferred orientation. Copyright (c) 2013 John Wiley & Sons, Ltd.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000320727900015 Publication Date 2013-05-14
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 5 Open Access
Notes ; The authors would like to thank De Nolf W. for his valuable feedback on the analysis of the X-ray diffraction data. We acknowledge SOLEIL for provision of SR facilities (proposal ID 20100979), and we would like to thank Dr. C. Mocuta for his assistance at the DIFFABS beamline. This research was supported by the Interuniversity Attraction Poles Program – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA 'XANES meets ELNES' (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. The EU Community's FP7 Research Infrastructures program for the CHARISMA Project (grant agreement 228330) and, within framework in particular, the access possibilities to the SOLEIL and IPANEMA facilities are also acknowledged. ; Approved Most recent IF: 1.298; 2013 IF: 1.187
Call Number UA @ admin @ c:irua:109579 Serial 5827
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Author Labrecque, J.J.; Beusen, J.M.; Van Grieken, R.E.
Title Determination of barium, lanthanum, cerium and neodymium in lateritic materials by various energy-dispersive X-ray fluorescence techniques and neutron activation analysis Type A1 Journal article
Year 1986 Publication X-ray spectrometry Abbreviated Journal
Volume 15 Issue 1 Pages 13-18
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract (down) A comparison of four methods for the determination of barium, lanthanum, cerium and neodymium in lateritic materials from Brazil is presented. Three of the methods were based on x-ray fluorescence (XRF) spectroscopy: two by radioisotope excitation (Co-57 and Am-241) and one by secondary target XRF (a molybdenum target with a tungsten anode). The other method was based on neutron activation analysis employing both a Ge(Li) coaxial detector and a high-purity germanium detector. The results from these four methods were similar for lanthanum, cerium and neodymium, but for barium at low concentrations (<500 ppm) the neutron activation and the secondary target XRF methods were not suitable. Data on the precision and accuracy of these methods using a series of standard reference rocks are given. The advantages and limitations of each of these methods with respect to the analysis of lateritic materials are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1986AYN6000003 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:116487 Serial 7774
Permanent link to this record