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“Classification of coal mine dust particles through fuzzy clustering of their energy-dispersive electron microprobe X-ray spectra”. Bondarenko I, van Espen P, Treiger B, Van Grieken R, Adams F, Microbeam analysis 3, 33 (1994)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
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“Classification of mineral particles by nonlinear mapping of electron microprobe energy-dispersive X-ray spectra”. Treiger B, Bondarenko I, van Espen P, Van Grieken R, Adams F, The analyst 119, 971 (1994). http://doi.org/10.1039/AN9941900971
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1039/AN9941900971
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“Determination of fluorine in uranium oxyfluoride particles as an indicator of particle age”. Kips R, Pidduck AJ, Houlton MR, Leenaers A, Mace JD, Marie O, Pointurier F, Stefaniak EA, Taylor PDP, van den Berghe S, van Espen P, Van Grieken R, Wellum R, Spectrochimica acta: part B : atomic spectroscopy 64, 199 (2009). http://doi.org/10.1016/J.SAB.2008.12.001
Abstract: As swipe samples from enrichment activities typically contain uranium particles with a detectable amount of fluorine, the question was raised whether the analysis of fluorine in particles could complement the information on the uranium isotope ratios. For this, uranium oxyfluoride particles were prepared from the controlled hydrolysis of uranium hexafluoride (UF6). The relative amount of fluorine was characterized by scanning electron microscopy combined with energy-dispersive X-ray spectrometry (SEM-EDX), as well as ion-microprobe secondary ion mass spectrometry (IM-SIMS). Of particular interest was the assessment of the reduction of the amount of fluorine over time, and after exposure to UV-light and high temperatures. Micro-Raman spectrometry (MRS) was applied to look for differences in molecular structure between these various sample types. Both SEM-EDX and IM-SIMS showed a general reduction of the fluorine-to-uranium ratio after 12 years of storage. The exposure to UV-light and high temperatures was found to have accelerated the loss of fluorine. A distinct peak at 865 cm− 1 Raman shift was detected for the majority of particles analyzed by MRS. For the particles that were heat-treated, the Raman spectra were similar to the spectrum of U3O8. Although often large variations were observed between particles from the same sample, the three particle measurement techniques (IM-SIMS, SEM-EDX and MRS) showed some consistent trends. They therefore appear promising in terms of the ability to place bounds on particle age, as well as shedding light on the complex processes involved in UO2F2 particle ageing.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1016/J.SAB.2008.12.001
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“Determination of sample thickness via scattered radiation in X-ray fluorescence spectrometry with filtered continuum excitation”. Araujo MF, van Espen P, Van Grieken R, X-ray spectrometry 19, 29 (1990). http://doi.org/10.1002/XRS.1300190107
Abstract: 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.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1002/XRS.1300190107
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“Effective sample weight from scatter peaks in energy-dispersive x-ray fluorescence”. van Espen P, Van 't dack L, Adams F, Van Grieken R, Analytical chemistry 51, 961 (1979). http://doi.org/10.1021/AC50043A042
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1021/AC50043A042
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“Evaluation of energy-dispersive x-ray spectra of low-Z elements from electron-probe microanalysis of individual particles”. Osán J, de Hoog J, van Espen P, Szalóki I, Ro C-U, Van Grieken R, X-ray spectrometry 30, 419 (2001). http://doi.org/10.1002/XRS.523
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1002/XRS.523
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“Fractal dimensional classification of aerosol particles by computer-controlled scanning electron microscopy”. Kindratenko VV, van Espen PJM, Treiger BA, Van Grieken RE, Environmental science and technology 28, 2197 (1994). http://doi.org/10.1021/ES00061A031
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1021/ES00061A031
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“IDAS: a Windows based software package for cluster analysis”. Bondarenko I, Treiger B, Van Grieken R, van Espen P, Spectrochimica acta: part B : atomic spectroscopy 51, 441 (1996)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
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“Non-linear mapping of microbeam proton-induced X-ray emission data for source identification of North Sea aerosols”. Treiger B, Injuk J, Bondarenko I, van Espen P, Van Grieken R, Breitenbach L, Wätjen U, Spectrochimica acta: part B : atomic spectroscopy 49, 345 (1994). http://doi.org/10.1016/0584-8547(94)80029-4
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1016/0584-8547(94)80029-4
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“Performance of a new compact EDXRF spectrometer for aerosol analysis”. Samek L, Injuk J, van Espen P, Van Grieken R, X-ray spectrometry 31, 84 (2002). http://doi.org/10.1002/XRS.551
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1002/XRS.551
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“Pixe analysis of aerosol samples collected over the atlantic-ocean from a sailboat”. Maenhaut W, Selen A, van Espen P, Van Grieken R, Winchester WJ, Nuclear instruments and methods 181, 399 (1981). http://doi.org/10.1016/0029-554X(81)90640-6
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.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1016/0029-554X(81)90640-6
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“Size-differentiated composition of aerosols in Khartoum, Sudan”. Eltayeb MAH, van Espen PJ, Cafmeyer J, Van Grieken RE, Maenhaut W, The science of the total environment 120, 281 (1992). http://doi.org/10.1016/0048-9697(92)90062-W
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1016/0048-9697(92)90062-W
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“Studying aerosol samples by non-linear mapping of electron probe microanalysis data”. Treiger B, van Malderen H, Bondarenko I, van Espen P, Van Grieken R, Analytica chimica acta 284, 119 (1993). http://doi.org/10.1016/0003-2670(93)80014-C
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1016/0003-2670(93)80014-C
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“M\alpha/L\alpha intensity ratios for Ta, W, Pt, Au, Pb and Bi for electron energies in the 11-40 keV range”. Trincavelli J, Montoro S, van Espen P, Van Grieken R, X-ray spectrometry 22, 372 (1993). http://doi.org/10.1002/XRS.1300220510
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.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1002/XRS.1300220510
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“Unraveling the Role of Lattice Substitutions on the Stabilization of the Intrinsically Unstable Pb2Sb2O7Pyrochlore: Explaining the Lightfastness of Lead Pyroantimonate Artists&rsquo, Pigments”. Marchetti A, Saniz R, Krishnan D, Rabbachin L, Nuyts G, De Meyer S, Verbeeck J, Janssens K, Pelosi C, Lamoen D, Partoens B, De Wael K, Chemistry Of Materials 32, 2863 (2020). http://doi.org/10.1021/acs.chemmater.9b04821
Abstract: The pyroantimonate pigments Naples yellow and lead tin antimonate yellow are recognized as some of the most stable synthetic yellow pigments in the history of art. However, this exceptional lightfastness is in contrast with experimental evidence suggesting that this class of mixed oxides is of semiconducting nature. In this study the electronic structure and light-induced behavior of the lead pyroantimonate pigments were determined by means of a combined multifaceted analytical and computational approach (photoelectrochemical measurements, UV-vis diffuse reflectance spectroscopy, STEM-EDS, STEM-HAADF, and density functional theory calculations). The results demonstrate both the semiconducting nature and the lightfastness of these pigments. Poor optical absorption and minority carrier mobility are the main properties responsible for the observed stability. In addition, novel fundamental insights into the role played by Na atoms in the stabilization of the otherwise intrinsically unstable Pb2Sb2O7 pyrochlore were obtained.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Impact Factor: 8.6
Times cited: 8
DOI: 10.1021/acs.chemmater.9b04821
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“Particle deposition in airways of chronic respiratory patients exposed to an urban aerosol”. Horemans B, Van Holsbeke C, Vos W, Darchuk L, Novakovic V, Fontan AC, de Backer J, van Grieken R, de Backer W, De Wael K, Environmental science and technology 46, 12162 (2012). http://doi.org/10.1021/es302755s
Abstract: Urban atmospheres in modern cities carry characteristic mixtures of particulate pollution which are potentially aggravating for chronic respiratory patients (CRP). Although air quality surveys can be detailed, the obtained information is not always useful to evaluate human health effects. This paper presents a novel approach to estimate particle deposition rates in airways of CRP, based on real air pollution data. By combining computational fluid dynamics with physical-chemical characteristics of particulate pollution, deposition rates are estimated for particles of different toxicological relevance, that is, minerals, iron oxides, sea salts, ammonium salts, and carbonaceous particles. Also, it enables some qualitative evaluation of the spatial, temporal, and patient specific effects on the particle dose upon exposure to the urban atmosphere. Results show how heavy traffic conditions increases the deposition of anthropogenic particles in the trachea and lungs of respiratory patients (here, +0.28 and +1.5 μg·h1, respectively). In addition, local and synoptic meteorological conditions were found to have a strong effect on the overall dose. However, the pathology and age of the patient was found to be more crucial, with highest deposition rates for toxic particles in adults with a mild anomaly, followed by mild asthmatic children and adults with severe respiratory dysfunctions (7, 5, and 3 μg·h1, respectively).
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
Impact Factor: 6.198
Times cited: 5
DOI: 10.1021/es302755s
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“Assessment of the air quality (NO2, SO2, O3 and particulate matter) in the Plantin-Moretus Museum/Print Room in Antwerp, Belgium, in different seasons of the year”. Krupińska B, Worobiec A, Rotondo GG, Novaković, V, Kontozova V, Ro C-U, Van Grieken R, De Wael K, Microchemical journal 102, 49 (2012). http://doi.org/10.1016/J.MICROC.2011.11.008
Abstract: The Plantin-Moretus Museum/Print Room in Antwerp, Belgium, gathers one of the most precious collections of typographical material and old printed books in the world. Rich decorations of this former printing-house and the history of the building itself underline its uniqueness. The cultural heritage (CH) objects collected in the museum, in particular books and manuscripts are vulnerable to the atmospheric pollution and can be irreversibly damaged. To assess the air quality inside the museum, four consecutive sampling campaigns were performed in each season of the year. The gas monitoring of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3) was carried out outside the building, in galleries and in showcases by means of using diffusive samplers. The particulate matter (PM) was collected in bulk form and as single particles and then analysed with use of energy dispersive X-ray fluorescence (EDXRF) and electron probe micro-analyser (EPMA), respectively. The museum complex turned out to show good protection against gaseous pollutants, especially SO2 and O3. The concentrations of these pollutants were significantly reduced inside the building in comparison to the outdoor ones. Similar protective character of the museum complex was established in case of the coarse fraction of PM; however with some limitations. Single particle analysis showed that the relative abundance of carbon-rich particles inside the museum was greater than outside. Moreover, these particles contributed more to the fine fraction of PM than to the coarse fraction. Therefore, for better preservation of cultural heritage, special attention should be paid to the small particles and their distribution within the museum.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
Impact Factor: 3.034
Times cited: 25
DOI: 10.1016/J.MICROC.2011.11.008
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“Air particulate emissions in developing countries : a case study in South Africa”. Worobiec A, Potgieter-Vermaak SS, Berghmans P, Winkler H, Burger R, Van Grieken R, Analytical letters 44, 1907 (2011). http://doi.org/10.1080/00032719.2010.539734
Abstract: Atmospheric aerosols were collected during the winter in Bethlehem, South Africa. The particulate mass concentrations, ambient carbon mass concentrations, and chemical composition of various particulate fractions showed that the area is highly polluted. The fine particle mass concentrations peaked at 1000 µg/m3 for PM2.5. Ambient carbon mass concentrations ranged from 20 to 40 µg/m3. Single particle analysis confirmed that the fine particle fraction was dominated by organic particles. The topographical conditions, causing a low inversion, together with the high amounts of emissions from biomass burning, result in unacceptable levels of air pollution and pose a considerable health threat to the population.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1080/00032719.2010.539734
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“Airborne particulate matter and BTEX in office environments”. Horemans B, Worobiec A, Buczyńska A, van Meel K, Van Grieken R, Journal of environmental monitoring 10, 867 (2008). http://doi.org/10.1039/B804475A
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1039/B804475A
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“Application of EDXRF and thin window EPMA for the investigation of the influence of hot air heating on the generation and deposition of particulate matter”. Spolnik Z, Bencs L, Worobiec A, Kontozova V, Van Grieken R, Microchimica acta 149, 79 (2005). http://doi.org/10.1007/S00604-004-0299-Y
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1007/S00604-004-0299-Y
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“Argentinean prehistoric pigments' study by combined SEM/EDX and molecular spectroscopy”. Darchuk L, Tsybrii Z, Worobiec A, Vázquez C, Palacios OM, Stefaniak EA, Gatto Rotondo G, Sizov F, Van Grieken R, Spectrochimica acta: part A: molecular and biomolecular spectroscopy 75, 1398 (2010). http://doi.org/10.1016/J.SAA.2010.01.006
Abstract: Composition of the prehistoric pigments (from Carriqueo rock shelter, Rio Negro province, Argentina) has been analysed by means of molecular spectroscopy (Fourier transform infrared (FTIR) and micro-Raman) and scanning electron microscopy (SEM) coupled to an energy-dispersive X-ray spectrometer (EDS). Red and yellow pigments were recognized as red and yellow ochre. The matrix of the pigments is composed of one or more substances. According to the matrix composition yellow and red pigments were also divided into two groupsi.e. those containing kaolinite or sulphates. Green pigment was detected as green earth, made up of celadonite as a chromophore.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1016/J.SAA.2010.01.006
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“Behavior of semi-volatile particles under a laser and electron beam: influence on the quality of analytical results”. Worobiec A, Potgieter-Vermaak S, Darchuk L, Vishnyakov V, Potgieter H, Van Grieken R, AIP conference proceedings 1267, 523 (2010). http://doi.org/10.1063/1.3482653
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1063/1.3482653
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“Characterisation of Amazon Basin aerosols at the individual particle level by X-ray microanalytical techniques”. Worobiec A, Szalóki I, Osán J, Maenhaut W, Stefaniak EA, Van Grieken R, Atmospheric environment : an international journal 41, 9217 (2007). http://doi.org/10.1016/J.ATMOSENV.2007.07.056
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1016/J.ATMOSENV.2007.07.056
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“Characterisation of individual atmospheric particles within the Royal Museum of the Wawel Castle in Cracow, Poland”. Worobiec A, Stefaniak EA, Kontozova V, Samek L, Karaszkiewicz P, van Meel K, Van Grieken R, e-Preservation Science 3, 63 (2006)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
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“Comparative assessment of air quality in two health resorts using carbon isotopes and palynological analyses”. Górka M, Jedrysek MO, Maj J, Worobiec A, Buczyńska A, Stefaniak E, Krata A, Van Grieken R, Zwozdziak A, Sówka I, Zwozdziak J, Lewicka-Szczebak D, Atmospheric environment 43, 682 (2009). http://doi.org/10.1016/J.ATMOSENV.2008.09.056
Abstract: This paper describes results of applying the palynological and carbon isotopic analysis of the organic fraction of Total Suspended Particles (TSP) to discriminate distinct pollution sources and assess the anthropogenic impact for the investigated areas. The samples of atmospheric particles were collected in Czerniawa and Cieplice (two health resorts in Lower Silesia, SW Poland) twice a year in summer and winter season (from July 2006 to February 2008). The palynological spectra represent in the vast majority local plant communities without a noticeable contribution of long-transported plant particles. Palynological analysis revealed also differences in the specificity of the two sampling areas, i.e. the higher contribution of identified organic material in Czerniawa stands for more natural character of this site, but is also responsible for the higher allergic pressure when compared to Cieplice. The carbon isotopic composition of TSP varied seasonally (ä13C value from −27.09 in summer to −25.47 in winter). The increased ä13C value in winter (heating period) is most probably caused by uncontrolled contribution of coal soot. On the basis of isotopic mass balance the calculated contribution of anthropogenic organic particles in the atmosphere reached in winter season 72% in Czerniawa and 79% in Cieplice.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1016/J.ATMOSENV.2008.09.056
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“Composition of aerosols from the shelter of the Chernobyl power plant”. Darchuk L, Worobiec A, Khan V, Krasnov V, Van Grieken R, AIP conference proceedings 1267, 512 (2010). http://doi.org/10.1063/1.3482646
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1063/1.3482646
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“Composition of pigments on human bones found in excavations in Argentina studied with micro-Raman spectrometry and scanning electron microscopy”. Darchuk L, Stefaniak EA, Vázquez C, Palacios OM, Worobiec A, Van Grieken R, e-Preservation Science 6, 112 (2009)
Abstract: Results on analysis of prehistoric pigments from excavations and pigments on coloured child bones from North Patagonia, Argentina, are reported. To analyze their composition we used two micro-analytical techniques: micro- Raman spectrometry (MRS) and scanning electron microscopy coupled with X-ray micro-analysis (SEM/EDX). Most investigated excavated pigments show red or yellow ochres consistent with reddish or yellow minerals, such as á- and ã-goethite, haematite, erdite, haapalaite and jarosite. Raman spectra show also evidence of calcium oxalate monohydrate and calcite indicating lichen activity. Pigments covering human bones were identified as hematite and magnetite. This study allows us to infer that pigments found in excavation were employed for burial ceremonies, even though distances between excavated pigment archaeological site and buried remains are quite far, more than 50 km in a straight line.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
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“Composition of prehistoric rock-painting pigments from Egypt (Gilf Kébir area)”. Darchuk L, Gatto Rotondo G, Swaenen M, Worobiec A, Tsybrii Z, Makarovska Y, Van Grieken R, Spectrochimica acta: part A: molecular and biomolecular spectroscopy 83, 34 (2011). http://doi.org/10.1016/J.SAA.2011.06.054
Abstract: The composition of rock-painting pigments from Egypt (Gilf Kebia area) has been analyzed by means of molecular spectroscopy such as Fourier transform infrared and micro-Raman spectroscopy and scanning electron microscopy coupled to an energy dispersive X-ray spectrometer and X-ray fluorescence analysis. Red and yellow pigments were recognized as red and yellow ochre with additional rutile.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1016/J.SAA.2011.06.054
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“Damage and molecular changes under a laser beam in SEM-EDX/MRS interface : a case study on iron-rich particles”. Worobiec A, Darchuk L, Brooker A, Potgieter H, Van Grieken R, Journal of Raman spectroscopy 42, 808 (2011). http://doi.org/10.1002/JRS.2789
Abstract: The control of damage to individual environmental particles by a laser beam during Raman spectroscopy carried out in ambient air is generally well understood. The nature and control of damage under vacuum conditions (e.g. in the scanning electron microscopy with energy X-ray detection combined with micro-Raman spectroscopyinterfaced SEM-EDX/MRS) are more complex and less well comprehended. The physical and chemical processes that affect the damage caused to small particles by lasers still remain somewhat unclear, but certainly the atmosphere (vacuum/air) and the beam intensity have very significant influences. Furthermore, it has been determined that some particles (e.g. haematite), although stable under an electron beam, are damaged by the laser beam, hampering their analysis. Additionally, when simultaneous analyses by SEM/EDX and MRS are considered, the correct choice of the collection surface plays a crucial role. As a result, the following collection substrates were tested to determine their influence on the laser beam damage process to the particle: silver and aluminium foils and silicon wafers. A test study was performed using artificial examples of haematite (Fe2O3) particles. Exposure of Fe2O3 particles in vacuum to 514- and 785-nm laser radiation often leads to their melting, transformation and evaporation. The dependence of the damage caused by the laser beam on the particle structure is reported here. Molecular and crystallographic changes have also been revealed. Formation of magnetite (as an effect of re-crystallisation) and Raman inactive structures was detected.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1002/JRS.2789
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“Fingerprinting of South African ordinary Portland cements, cement blends and mortars for identification purposes: discrimination with starplots and PCA”. Potgieter-Vermaak SS, Potgieter JH, Worobiec A, Van Grieken R, Marjanovic L, Moeketsi S, Cement and concrete research 37, 834 (2007). http://doi.org/10.1016/J.CEMCONRES.2007.02.013
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1016/J.CEMCONRES.2007.02.013
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