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“Integration of analysis techniques of different scales using X ray induced and electron induced X ray spectrometry for applications in preventive conservation and environmental monitoring”. Van Grieken R, Darchuk L, Kontozova V, Potgieter-Vermaak S, van Meel K, Stefaniak E, Worobiec A page 53 (2011).
Abstract: In the past years, and also within the framework of this CRP, we have used a combination of several nuclear and non-nuclear techniques in fundamental research and especially in various applications. Most work has been done with energy-dispersive X ray fluorescence in combination with electron probe X ray microanalysis, but several other more common analysis techniques have been used as well. The applications have included mostly preventive conservation (e.g. characterisation of damaging atmospheric particles in many museums) and environmental monitoring (e.g. for atmospheric particles in relation to their health effects in outdoor and especially indoor environments). Fundamental aspects have been in the optimising of interfaced electron microprobe and Raman microprobe analysis and the evaluation of the potential of such an instrument for atmospheric aerosols; quite a few unexpected and unpredicted problems have appeared in the latter study.
Keywords: H2 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
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“Interfaced SEM/EDX and micro-Raman spectrometry for characterisation of heterogeneous environmental particles: fundamental and practical challenges”. Worobiec A, Potgieter-Vermaak S, Brooker A, Darchuk L, Stefaniak E, Van Grieken R, Microchemical journal 94, 65 (2010). http://doi.org/10.1016/J.MICROC.2009.09.003
Abstract: The molecular character of atmospheric particulate matter is of prime importance when interpreting air pollution trends and its subsequent influence on environmental monitoring and preventative conservation. The known methods of estimating the molecular composition normally involve elemental analysis of particles (both as bulk and computer controlled analyses of single particles) with subsequent multivariate analyses to clusterise the elements in groups of elements that are closely related to each other. With this approach one can at best suggest associations. Evidently the application of molecular spectroscopy in addition to elemental concentration profiles would provide intimate information regarding the nature of the particles and consequently their fate. This paper gives an overview of research performed in our laboratory and describes the optimisation of experimental parameters to use scanning electron microscopy with energy-dispersive X-ray detection (SEM/EDX) or electron probe X-ray microanalysis (EPXMA) in parallel with micro-Raman Spectrometry (MRS) to investigate single environmental particles. The challenges associated with the two stand-alone techniques are revealed and consequently those posed with an interfaced approach are discussed. Preliminary results, of an initial investigation of the SEM/EDX interfaced with MRS to ultra-fine heterogeneous environmental particles, are given.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
DOI: 10.1016/J.MICROC.2009.09.003
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“Methods, fluxes and sources of gas phase alkyl nitrates in the coastal air”. Dirtu AC, Buczyńska AJ, Godoi AFL, Favoreto R, Bencs L, Potgieter-Vermaak SS, Godoi RHM, Van Grieken R, Van Vaeck L, Environmental monitoring and assessment 186, 6445 (2014). http://doi.org/10.1007/S10661-014-3866-7
Abstract: The daily and seasonal atmospheric concentrations, deposition fluxes and emission sources of a few C3C9 gaseous alkyl nitrates (ANs) at the Belgian coast (De Haan) on the Southern North Sea were determined. An adapted sampler design for low- and high-volume air-sampling, optimized sample extraction and clean-up, as well as identification and quantification of ANs in air samples by means of gas chromatography mass spectrometry, are reported. The total concentrations of ANs ranged from 0.03 to 85 pptv and consisted primarily of the nitro-butane and nitro-pentane isomers. Air mass backward trajectories were calculated by the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to determine the influence of main air masses on AN levels in the air. The shorter chain ANs have been the most abundant in the Atlantic/Channel/UK air masses, while longer chain ANs prevailed in continental air. The overall mean N fluxes of the ANs were slightly higher for summer than those for winter-spring, although their contributions to the total nitrogen flux were low. High correlations between AN and HNO2 levels were observed during winter/spring. During summer, the shorter chain ANs correlated well with precipitation. Source apportionment by means of principal component analysis indicated that most of the gas phase ANs could be attributed to traffic/combustion, secondary photochemical formation and biomass burning, although marine sources may also have been present and a contributing factor.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
DOI: 10.1007/S10661-014-3866-7
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“Micro-Raman spectroscopy for the analysis of environmental particles”. Potgieter-Vermaak S, Worobiec A, Darchuk L, Van Grieken R page 193 (2011).
Keywords: H1 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
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“Micro-structural characterization of black crust and laser cleaning of building stones by micro-Raman and SEM techniques”. Potgieter-Vermaak SS, Godoi RHM, Van Grieken R, Potgieter JH, Oujja M, Castillejo M, Spectrochimica acta: part A: molecular and biomolecular spectroscopy 61, 2460 (2005). http://doi.org/10.1016/J.SAA.2004.09.010
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.SAA.2004.09.010
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“Molecular and elemental characterisation of mineral particles by means of parallel micro-Raman spectrometry and Scanning Electron Microscopy/Energy Dispersive X-ray Analysis”. Stefaniak EA, Worobiec A, Potgieter-Vermaak S, Alsecz A, Török S, Van Grieken R, Spectrochimica acta: part B : atomic spectroscopy 61, 824 (2006). http://doi.org/10.1016/J.SAB.2006.04.009
Keywords: A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.SAB.2006.04.009
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“New insights in technology characterization of medieval Valencia glazes”. Romero-Pastor J, Garcia-Porras A, Van Grieken R, Potgieter-Vermaak S, Coll-Conesa J, Cardell C, X-ray spectrometry 44, 426 (2015). http://doi.org/10.1002/XRS.2613
Abstract: 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.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1002/XRS.2613
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“Particulate matter analysis at elementary schools in Curitiba, Brazil”. Avigo D, Godoi AFL, Janissek PR, Makarovska Y, Krata A, Potgieter-Vermaak S, Alfoldy B, Van Grieken R, Godoi RHM, Analytical and bioanalytical chemistry 391, 1459 (2008). http://doi.org/10.1007/S00216-008-2031-Y
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S00216-008-2031-Y
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“Particulate matter and gaseous pollutants in residences in Antwerp, Belgium”. Stranger M, Potgieter-Vermaak SS, Van Grieken R, The science of the total environment 407, 1182 (2009). http://doi.org/10.1016/J.SCITOTENV.2008.10.019
Abstract: This comprehensive study, a first in Flanders, Belgium, aimed at characterizing the residential indoor air quality of subgroups that took part in the European Community Respiratory Health Survey (ECRHS I1991 and ECHRS II1996) questionnaire-based asthma and related illnesses studies. This pilot study aimed at the evaluation of particulate matter and various inorganic gaseous compounds in residences in Antwerp. In addition personal exposure to the gaseous compounds of one individual per residence was assessed. The main objective was to obtain some base-line pollutant levels and compare these with studies performed in other cities, to estimate the indoor air quality in residences in Antwerp. Correlations between the various pollutant levels, indoor:outdoor ratios and the micro-environments of each residence were investigated. This paper presents results on indoor and ambient PM1, PM2.5 and PM10 mass concentrations, its elemental composition in terms of K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb, Al, Si, S and Cl and the water-soluble ionic concentrations in terms of SO42−, NO32−, Cl−, NH4+ K+, Ca2+. In addition, indoor, ambient and personal exposure levels of the gases NO2, SO2, and O3 were determined. Elevated indoor:outdoor ratios were found for NO2 in residences containing gas stoves. In smoker's houses increased PM concentrations of 58 and 43% were found for the fine and coarse fractions respectively. Contrary to the fact that all I/O ratios of the registered elements in each individual house were significantly correlated to each other, no correlation could be established between the I/O ratios of the different houses, thus indicating a unique micro-environment for each residence. Linear relationships between the particulate matter elemental composition, SO2 and O3 levels indoors and outdoors could be established. No linear relationships between indoor and outdoor NO2 and particulate mass concentrations were found.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.SCITOTENV.2008.10.019
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“Preliminary evaluation of micro-Raman spectrometry for the characterization of individual aerosol particles”. Potgieter-Vermaak SS, Van Grieken R, Applied spectroscopy 60, 39 (2006). http://doi.org/10.1366/000370206775382848
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1366/000370206775382848
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“Raman spectroscopy for the analysis of coal : a review”. Potgieter-Vermaak S, Maledi N, Wagner N, van Heerden JHP, Van Grieken R, Potgieter JH, Journal of Raman spectroscopy 42, 123 (2011). http://doi.org/10.1002/JRS.2636
Abstract: The advances in the characterization of amorphous carbons by Raman spectroscopy over the last four decades are of interest to many industries, especially those involving the combustion, gasification and pyrolysis of coal. Many researchers report on the Raman character of the natural organic matter in carbon-containing compounds, such as coal, and relate the Raman bands to the structural order of the amorphous carbons. The basis of most of these studies evolved around the assignment of the G (graphitic, ∼1580 cm−1) band to crystalline graphite and any other bands, called D bands, (disorder, various from 1100 to 1500 cm−1) to any type of structural disorder in the graphitic structure. Concerning coal analysis, the information gained by Raman investigations has been used to describe char evolution as a function of temperature, the presence of catalysts and different gasification conditions. In addition, researchers looked at maturation, grade, doppleritization and many more aspects of interest. One aspect that has, however, not been addressed by most of the researchers is the natural inorganic matter (NIM) in the carbon-containing compounds. Micro-Raman spectroscopy (MRS) has many advantages over other characterization tools, i.e. in situ analysis, nondestructive, no sample preparation, low detection limit, micrometer-scale characterization, versatility and sensitivity to many amorphous compounds. With the distinct advantages it has over that of other molecular characterization tools, such as powder X-ray diffraction (PXRD), Fourier-transform infrared spectrometry (FT-IR) and scanning electron microscopy with X-ray detection (SEM/EDS), it is surprising that it has not yet been fully exploited up to this point for the characterization of the NIM in coal and other amorphous carbons. This paper reviews the work published on the Raman characterization of the natural organic matter (NOM) of coals and reports on preliminary results of the NIM character of various South African coals, whereby various inorganic compounds and minerals in the coal have been characterized.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1002/JRS.2636
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“Die risikoprofiel van Pb en Cr in stedelike padstof”. Potgieter-Vermaak S, Van Grieken R, Potgieter H, Litnet akademies : 'n joernaal vir die geesteswetenskappe 9, 1 (2012)
Abstract: The risk profile of Cr and Pb in urban road deposited sediment Exponential urbanisation and industrial growth occur on a global scale and result in an ecological burden, of which one important part is pollution. It is well known that the extent of air pollution has escalated over the past two decades in several parts of the world, despite mitigating measures and legislation. Current research points to the fact that air pollution in urban and industrial areas is substantially different from that found in rural areas. Road dust (RD) contributes up to 35% of airborne particulate matter due to resuspension thereof, and poses a health concern due to carcinogenic and toxic components potentially present in the micron-sized fractions. Although literature does report on the concentrations of trace, toxic metals and metalloids present in RD (Hooker and Nathanail 2006), the molecular make-up of particulates generated due to the resuspension of the RD is not well documented. In vitro and animal toxicological studies have confirmed that the chemical composition of inhaled particles plays a major role in its toxic, genotoxic and carcinogenic mechanisms, but the component-specific toxic effects are still not understood. Transition metals binding to air particle matter can result in reactive oxygen species in the human body (particularly in the lungs), and this is a significant risk, especially for vulnerable population groups like elderly people, children and terminally ill patients. The characterisation of the molecular composition of the fine fraction is evidently of importance for public health. During an earlier study, road dust from an inner-city environment in the UK was collected and partially characterised (Barrett e.a. 2010). These same-size fractions were analysed for their elemental concentrations, using X-ray Fluorescence Spectrometry (XRFS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). In addition, single-particle analysis was performed on the different fractions by means of Computer Controlled Electron Probe X-ray Micro Analysis (CC-EPXMA) and their molecular structure probed by studying elemental associations. These findings were correlated with Micro Raman Spectroscopy (MRS) results. It was found that the fine fraction (<38 μm) had the highest Pb (238 ppm) and Cr (171 ppm) concentrations. The CC-EPXMA data showed >50% association of Cr-rich particles with Pb and the MRS data showed that the Cr was mostly present as lead chromate and therefore in the Cr(VI) oxidation state. Concentrations of both Pb and Cr decreased substantially (279 (<38 mm) 13 ppm (<1mm); 171 (<38 mm) 91 ppm (<1mm) respectively) in the larger fractions. Apart from rather alarmingly high concentrations of oxidative stressors (Cu, Fe, Mn), the carcinogenic and toxic potential of the inhalable fraction is evident. Preliminary bioaccessibility data indicated that both Cr and Pb are readily
Keywords: A2 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Risk assessment and spatial chemical variability of PM collected at selected bus stations”. Godoi RHM, Godoi AFL, de Quadros LC, Polezer G, Silva TOB, Yamamoto CI, Van Grieken R, Potgieter-Vermaak S, Air quality, atmosphere &, health , 1 (2013). http://doi.org/10.1007/S11869-013-0210-2
Abstract: The chemical characterization of particulate matter inside and outside of confined bus shelters has been discerned for the first time. Transit patrons are at risk due to the close vicinity of densely trafficked areas resulting in elevated pollution footprints. Incomplete combustion processes, as well as exhaust and wear and tear emissions from public and personal transportation vehicles, are key contributors to degraded urban air quality and are often implicated as causal to various diseases in humans. Urban planning, therefore, includes efficient public transport systems to mitigate the effect. The bus rapid transit system was inaugurated in Curitiba to ensure dedicated traffic lanes, major bus interchanges and semi-confined bus stops called tube stations. To assess the chemical risk that the passengers are exposed to, an investigation of the aerosol inside and outside five of these tube stations was launched. Electron probe X-ray micro-analysis and X-ray fluorescence were used to determine the elemental composition of individual and of bulk particle samples. An aethalometer quantified the black carbon. Elemental concentrations inside the shelters were in general higher than outside, especially for traffic-related elements. The lead concentration exceeded the NAAS standard at times, although the average was below the guideline. The biogenic, organic and soot clusters showed the highest abundance for the city centre sites. The overall carcinogenic risk could be classed as moderate, and the risk was significant at two sites during one of the sampling campaigns. The non-carcinogenic risk is well below the significant value.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S11869-013-0210-2
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“Substrate selection for optimum qualitative and quantitative single atmospheric particles analysis using nano-manipulation, sequential thin-window electron probe X-ray microanalysis and micro-Raman spectrometry”. Godoi RHM, Potgieter-Vermaak S, de Hoog J, Kaegi R, Van Grieken R, Spectrochimica acta: part B : atomic spectroscopy 61, 375 (2006). http://doi.org/10.1016/J.SAB.2006.02.004
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.SAB.2006.02.004
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“NO2 verkeersmetingen in Vlaanderen door passieve bemonstering”. Potgieter-Vermaak S, Stranger M, Verlinden L, Roekens E, Van Grieken R, Die Suid-Afrikaanse tydskrif vir natuurwetenskap en tegnologie 27, 266 (2008)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“X ray fluorescence in member states: Belgium: integration of analysis techniques of different scales using X ray induced and electron induced X ray spectrometry for applications in preventive conservation and environmental monitoring”. Van Grieken R, Potgieter-Vermaak S, Darchuk L, Worobiec A, XRF newsletter , 9 (2009)
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
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