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“Automatic absorption correction in x-ray fluorescence analysis of intermediate thickness samples using a dual external reference signal”. Van Dyck P, Markowicz A, Van Grieken R, X-ray spectrometry 9, 70 (1980). http://doi.org/10.1002/XRS.1300090209
Abstract: 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.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1002/XRS.1300090209
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“Background aerosol composition in the Namib Desert, South West-Africa (Namibia)”. Annegarn HJ, Van Grieken RE, Dibby DM, Von Blottnitz F, Atmospheric environment : an international journal 17, 2045 (1983). http://doi.org/10.1016/0004-6981(83)90361-X
Abstract: A remote site in the Namib Desert was selected for sampling background aerosols in southern Africa, as one of a wide network of stations spanning the Southern Hemisphere in a programme designed to measure the background concentrations of trace elements in the atmosphere. A series of samples was collected over a 6-month period using a single-orifice cascade impactor, which fractionated the particles into six size groups. Analysis was performed using particle-induced X-ray emission (PIXE), yielding results for S, Cl, K, Ca, Ti, Mn, Fe, Br and Sr, and occasionally also for V, Cr, Ni, Cu, Zn and Pb. No direct correlations with wind direction were observed excluding strong local or regional sources of particles. K, Ca, Ti, Mn and Fe can be identified with a dust dispersion source. Cl, large particle S and Br, and part of the K and Sr are derived from sea spray. Relative to the soil components small particle K is not enriched as it normally is in regions with less scarce vegetation. Cr, V, Ni, Cu, Zn and Pb concentrations and enrichments in the aerosol are lower than practically all values measured at any other location hitherto. The concentration of the small particle sulphur, 200 ng m−3, is believed to be related to anaerobic conditions and plankton blooms in the ocean upwelling zones off Namibia.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0004-6981(83)90361-X
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“Barite formation in the Southern Ocean water column”. Stroobants N, Dehairs F, Goeyens L, Vanderheijden N, Van Grieken R, Marine chemistry 35, 411 (1991). http://doi.org/10.1016/S0304-4203(09)90033-0
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/S0304-4203(09)90033-0
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“Base cation fluxes in mountain landscapes of Lake Baikal southern shore”. Semenov MY, Van Grieken R, Communications in soil science and plant analysis 38, 2635 (2007). http://doi.org/10.1080/00103620701662851
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/00103620701662851
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“Benzene concentrations on board chemical tankers”. Jacobs W, Dubois D, Floren E, Aerts D, Goris J, Buczyńska A, Van Grieken R, WMU journal of maritime affairs 10, 117 (2011). http://doi.org/10.1007/S13437-010-0002-6
Abstract: Maritime transport of benzene is regulated by the International Maritime Organisation (IMO). Two important guidelines for a ships crew in this matter are IMO circulars 1095 and 1220. The first one describes the minimum safety standards for ships carrying liquids in bulk containing benzene while circular 1220 deals with structural guidelines for new ships carrying liquids in bulk containing benzene, but also technical developments could help in improving safety and health protection on board chemical tankers carrying benzene in bulk. The aim of the present paper is to determine the benzene concentration in the working and living environment on board a modern chemical tanker carrying benzene in bulk, where all safety, technical and operational procedures described by IMO in the above-mentioned circulars are followed. During specific cargo operations, we measured the benzene concentrations on different locations on board by means of Radiello® passive diffusive samplers. Despite all measures taken, we found an important difference in benzene concentration between operations with a benzene cargo compared to operations without benzene on board, as well as inside and outside the accommodation. Moreover, even during discharge operations, where the emission is theoretically zero, we found an important increase in the benzene concentration. In addition, we found less favourable results for the engine room.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S13437-010-0002-6
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“Biogeochemical study of a coccolithophore bloom in the northern Bay of Biscay (NE Atlantic Ocean) in June 2004”. Harlay J, Borges AV, van der Zee C, Delille B, Godoi RHM, Schiettecatte L-S, Roevros N, Aerts K, Lapernat P-E, Rebreanu L, Groom S, Daro M-H, Van Grieken R, Chou L, Progress in oceanography 86, 317 (2010). http://doi.org/10.1016/J.POCEAN.2010.04.029
Abstract: The present paper synthesizes data obtained during a multidisciplinary cruise carried out in June 2004 at the continental margin of the northern Bay of Biscay. The data-set allows to describe the different stages of a coccolithophore bloom dominated by Emiliania huxleyi. The cruise was carried out after the main spring phytoplankton bloom that started in mid-April and peaked in mid-May. Consequently, low phosphate (PO4 < 0.2 μM) and silicate (DSi < 2.0 μM) concentrations, low partial pressure of carbon dioxide (pCO2) and high calcite saturation degree in surface waters combined with thermal stratification, probably favoured the blooming of coccolithophores. During the period of the year our cruise was carried out, internal tides induce enhanced vertical mixing at the continental shelf break leading to the injection of inorganic nutrients to surface waters that probably trigger the bloom. The bloom developed as the water-column stratified and as the water mass was advected over the continental shelf, following the general residual circulation in the area. The most developed phase of the bloom was sampled in a remote sensed high reflectance (HR) patch over the continental shelf that was characterized by low chlorophyll-a (Chl-a) concentration in surface waters (<1.0 μg L−1), high particulate inorganic carbon (PIC) concentration (not, vert, similar8 μmol L−1) and coccolithophore abundance up to 57 × 106 cells L−1. Transparent exopolymer particles (TEP) concentrations ranged between 15 and 75 μg C L−1 and carbon content of TEP represented up to 26% of the particulate organic carbon (POC; maximum concentration of 15.5 μmol L−1 in the upper 40 m). Integrated primary production (PP) ranged between 210 and 680 mg C m−2 d−1 and integrated calcification (CAL) ranged between 14 and 140 mg C m−2 d−1, within the range of PP and CAL values previously reported during coccolithophore blooms in open and shelf waters of the North Atlantic Ocean. Bacterial protein production (BPP) measurements in surface waters (0.30.7 μg C L−1 h−1) were much higher than those reported during early phases of coccolithophore blooms in natural conditions, but similar to those during peak and declining coocolithophorid blooms reported in mesocosms. Total alkalinity anomalies with respect to conservative mixing (ΔTA) down to −49 μmol kg−1 are consistent with the occurrence of biogenic precipitation of calcite, while pCO2 remained 15107 μatm lower than atmospheric equilibrium (372 μatm). The correlation between ΔTA and pCO2 suggested that pCO2 increased in part due to calcification, but this increase was insufficient to overcome the background under-saturation of CO2. This is related to the biogeochemical history of the water masses due to net carbon fixation by the successive phytoplankton blooms in the area prior to the cruise, hence, the investigated area remained a sink for atmospheric CO2 despite calcification.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.POCEAN.2010.04.029
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“Bremsstrahlung background in electron-probe X-ray-microanalysis of thin films”. Markowicz AA, Storms HM, Van Grieken RE, Analytical chemistry 57, 2885 (1985). http://doi.org/10.1021/AC00291A032
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/AC00291A032
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“A case study of high-temperature corrosion in rotary cement kilns”. Potgieter JH, Godoi RHM, Van Grieken R, Journal of the South African Institute of Mining and Metallurgy 104, 603 (2004)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“A case study of ship track formation in a polluted marine boundary layer”. Noone KJ, Johnson DW, Taylor JP, Ferek RJ, Garrett T, Hobbs PV, Durkee PA, Nielsen K, Öström E, O'Dowd CD, Smith MH, Russell LM, Flagan RC, Seinfeld JH, de Bock L, Van Grieken RE, Hudson JG, Brooks I, Gasparovic RF, Pockalny RA, Journal of the atmospheric sciences 57, 2748 (2000). http://doi.org/10.1175/1520-0469(2000)057<2748:ACSOST>2.0.CO;2
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1175/1520-0469(2000)057<2748:ACSOST>2.0.CO;2
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“A case study of ships forming and not forming tracks in moderately polluted clouds”. Noone KJ, Öström E, Ferek RJ, Garrett T, Hobbs PV, Johnson DW, Taylor JP, Russell LM, Flagan RC, Seinfeld JH, O'Dowd CD, Smith MH, Durkee PA, Nielsen K, Hudson JG, Pockalny RA, de Bock L, Van Grieken RE, Gasparovic RF, Brooks I, Journal of the atmospheric sciences 57, 2729 (2000). http://doi.org/10.1175/1520-0469(2000)057<2729:ACSOSF>2.0.CO;2
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1175/1520-0469(2000)057<2729:ACSOSF>2.0.CO;2
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“The cathedral of Bari, Italy: evaluation of environmental effects on stone decay phenomena”. Torfs K, Van Grieken R, Zezza F, Garcia N, Macri F, Studies in conservation = Études de conservation 42, 193 (1997). http://doi.org/10.2307/1506750
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.2307/1506750
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“Characterisation of particulate matter in the Royal Museum of Fine Arts, Antwerp, Belgium”. Gysels K, Deutsch F, Van Grieken R, Atmospheric environment : an international journal 36, 4103 (2002). http://doi.org/10.1016/S1352-2310(02)00229-7
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/S1352-2310(02)00229-7
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“Characterisation of soot emitted by domestic heating, aircraft and cars using diesel or biodiesel”. Smekens A, Godoi RHM, Berghmans P, Van Grieken R, Journal of atmospheric chemistry 52, 45 (2005). http://doi.org/10.1007/S10874-005-6903-7
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S10874-005-6903-7
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“A characterisation of the surface properties of an ultra fine fly ash (UFFA) used in the polymer industry”. Potgieter-Vermaak SS, Potgieter JH, Kruger RA, Spolnik Z, Van Grieken R, Fuel 84, 2295 (2005). http://doi.org/10.1016/J.FUEL.2005.05.013
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.FUEL.2005.05.013
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“Characterisation of wood combustion particles using electron probe microanalysis”. Osán J, Alföldy B, Török S, Van Grieken R, Atmospheric environment : an international journal 36, 2207 (2002). http://doi.org/10.1016/S1352-2310(02)00153-X
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/S1352-2310(02)00153-X
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“Characterization of a 2,2'-diaminodiethylamine-cellulose filter toward metal cation extraction”. Smits JA, Van Grieken RE, Analytical chemistry 52, 1479 (1980). http://doi.org/10.1021/AC50059A022
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/AC50059A022
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“Characterization of aerosol-associated lead by DPASV and LAMMA”. Wonders JHAM, Houweling S, de Bont FAJ, van Leeuwen HP, Eeckhaoudt SM, Van Grieken R, International journal of environmental analytical chemistry 56, 193 (1994). http://doi.org/10.1080/03067319408034100
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/03067319408034100
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“Characterization of airborne particulate matter collected over the North Sea”. Rojas CM, Otten PM, Van Grieken RE, Journal of aerosol science 20, 1257 (1989). http://doi.org/10.1016/0021-8502(89)90811-2
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0021-8502(89)90811-2
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“Characterization of colloidal and particulate matter transported by the Magela Creek system, Northern Australia”. Hart BT, Douglas GB, Beckett R, van Put A, Van Grieken R, Hydrological processes 7, 105 (1993)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Characterization of gas concrete materials used in buildings of Turkey”. Damla N, Čevik U, Kobya AI, Celik A, Van Grieken R, Kobya Y, Journal of hazardous materials 168, 681 (2009). http://doi.org/10.1016/J.JHAZMAT.2009.02.092
Abstract: The activity concentration of 226Ra, 232Th and 40K in gas concrete samples collected from different suppliers and some provinces in Turkey were measured using gamma-ray spectrometry. Knowledge of radioactivity in gas concrete used in building materials enables one to assess any possible radiological risks to human health. The mean activity concentrations observed in the gas concrete samples were 82.0, 28.2 and 383.9 Bq kg−1 for 226Ra, 232Th and 40K, respectively. The radium equivalent activity, external and internal hazard indices as well as terrestrial absorbed dose and annual effective dose rate was calculated. The results indicate that the radium equivalent activity values of gas concrete samples are lower than the limit of 370 Bq kg−1, equivalent to a gamma-dose of 1.5 mSv y−1. Moreover, mass attenuation coefficients were measured in some gas concrete samples. It was found that the mass attenuation coefficients decreased with increasing photon energies. Also, chemical compositions and structural analysis (XRD and SEM) of the gas concrete samples were investigated.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.JHAZMAT.2009.02.092
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“Characterization of individual estuarine and marine particles by LAMMA and EPXMA”. Wouters L, Bernard P, Van Grieken R, International journal of environmental analytical chemistry 34, 17 (1988). http://doi.org/10.1080/03067318808029918
Abstract: Laser microprobe mass analysis (LAMMA) was applied to particulate matter from the Atlantic Ocean. Inferring information about the surface layer by LAMMA was not probe X-ray microanalysis (EPXMA). Geochemically relevant groups of particles had been identified by EPXMA and cluster analysis. For both locations, the most abundant ones appeared to be those rich in silicon and the alumino-silicates. Afterwards LAMMA was applied to obtain more information about the trace element composition and surface characteristics. The iron-rich phase appeared to contain significant amounts of heavy metals and of phosphate. Lead appeared to be associated in detectable amounts with alumino-silicates in the Scheldt but not with those in the Atlantic Ocean. Inferring information about the surface layer by LAMMA was not always unambiguous.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/03067318808029918
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“Characterization of individual giant aerosol particles above the North Sea”. van Malderen H, Rojas C, Van Grieken R, Environmental science and technology 26, 750 (1992). http://doi.org/10.1021/ES00028A013
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/ES00028A013
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“Characterization of individual particle types in coastal air by laser microprobe mass analysis”. Bruynseels F, Storms H, Tavares T, Van Grieken R, International journal of environmental analytical chemistry 23, 1 (1985). http://doi.org/10.1080/03067318508076430
Abstract: Laser Microprobe Mass Analysis (LAMMA) was used in a preliminary study to characterize aerosol particles from a beach and inland sites and from a heavily industrialized area. As many as six types of both positive and negative mass spectra with different inorganic and organic signals could be distinguished in the different particle size ranges. Information about the elemental composition and the speciation of S and N was obtained. With increasing distance from sea, progressive uptake of nitrate in seasalt particles was found. Complex particles, containing soot and organic ammonium sulfate, were also detected.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/03067318508076430
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“Characterization of individual particles in the North Sea surface microlayer and underlying seawater: comparison with atmospheric particles”. Xhoffer C, Wouters L, Van Grieken R, Environmental science and technology 26, 2151 (1992). http://doi.org/10.1021/ES00035A013
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/ES00035A013
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“Characterization of indoor air quality in primary schools in Antwerp, Belgium”. Stranger M, Potgieter-Vermaak SS, Van Grieken R, Indoor air: international journal of indoor quality and climate 18, 454 (2008). http://doi.org/10.1111/J.1600-0668.2008.00545.X
Abstract: The indoor air quality of 27 primary schools located in the city centre and suburbs of Antwerp, Belgium, was assessed. The primary aim was to obtain correlations between the various pollutant levels. Indoor:outdoor ratios and the building and classroom characteristics of each school were investigated. This paper presents results on indoor and local outdoor PM2.5 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 its black smoke content. In addition, indoor and local outdoor levels of the gases NO2, SO2, O3, and BTEX (benzene, toluene, ethyl benzene, and xylene isomers) were determined. Black smoke, NO2, SO2 and O3, occurred at indoor:outdoor ratios below unity, indicating their significant outdoor sources. No linear correlation was established between indoor and outdoor levels for PM2.5 mass concentrations and BTEX; their indoor:outdoor ratios exceeded unity except for benzene. Classroom PM2.5 occurred with a different elemental composition than local outdoor PM2.5. The re-suspension of dust because of room occupation is probably the main contributor for the I/O ratios higher than 1 reported for elements typically constituting dust particles. Finally, increased benzene concentrations were reported for classrooms located at the lower levels.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1111/J.1600-0668.2008.00545.X
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“Characterization of indoor and outdoor atmospheric pollutants impacting architectural monuments : the case of San Jerónimo Monastery (Granada, Spain)”. Kontozova-Deutsch V, Cardell carolina, Urosevic M, Ruiz-Agudo E, Deutsch F, Van Grieken R, Environmental earth sciences 63, 1433 (2011). http://doi.org/10.1007/S12665-010-0657-5
Abstract: Indoor and outdoor concentrations of atmospheric gaseous pollutants as well as composition, size, and morphology of particulate matter have been investigated at the monastery of San Jerónimo in Granada (Southern Spain). Complementary micro- and nano-analytical techniques were applied; elemental and mineralogical composition and morphological characteristics of particulate matter were investigated combining electron probe microanalysis at the single particle level, and bulk aerosol samples were analyzed using energy-dispersive X-ray fluorescence, X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray analyzer and transmission electron microscopy (TEM). Microclimatic conditions at the monastery were monitored, and gas concentrations were assessed by means of diffusion tubes subsequently analyzed with ion chromatography. Results revealed high abundances of soil dust particles (aluminosilicates, calcite, dolomite, quartz), salt aerosols (chlorides, sulfates and ammonium-rich salts), and NO2 and SO2 both outdoors and indoors. Amorphous black carbon particles had surprisingly high abundances for Granada, a non-industrialized city. The composition of indoor particles corresponds to severe weathering affecting the construction materials and artworks inside the church; moreover their composition promotes a feedback process that intensifies the deterioration. Chemical reactions between chloride-rich salts and pigments from paintings were confirmed by TEM analyses. Indoors, blackening of surface decorative materials is fostered by particle re-suspension due to cleaning habits in the monastery (i.e. dusting). This is the first air quality study performed in a monument in the city of Granada with the aim of developing a strategy for preventive conservation.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S12665-010-0657-5
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“Characterization of North-Sea aerosols by individual particle analyses”. Bruynseels F, Storms H, Van Grieken R, Van der Auwera L, Atmospheric environment : an international journal 22, 2593 (1988). http://doi.org/10.1016/0004-6981(88)90493-3
Abstract: On aerosol and rain water samples, collected in the Southern Bight of the North Sea, single particle analyses were performed using both laser microprobe mass analysis and electron-probe X-ray microanalysis in combination with an automated image analysis system. In the aerosols collected from an air mass that had travelled from the Atlantic Ocean along the coast of North France, pure seasalt constituted the most abundant particle type, while aluminosilicates (mostly spherical fly-ash particles) amounted to about 20% and mixed seasalt/aluminosilicate, carbonaceous particles, CaSO4 and spherical iron oxides contributed each 510 %. In air masses that had a longer residence time over the continent, spherical iron oxides, carbonaceous particles and ammonium sulfates together made up 70 % of the total particle load. Seasalt particles were nearly all enriched in sulfate or nitrate, but they were seen to be washed out efficiently after a rain shower. In rain water, some 40 % of the particles appeared to be spherical or irregularly shaped aluminosilicates, from fly-ash and dust dispersal, but more than 50 % consisted of SiO2. The high relative abundance of these particles in rain water may be the result of Al leaching from fly-ash, or of more efficient scavenging by rain droplets.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0004-6981(88)90493-3
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“Characterization of the atmospheric aerosol over the eastern equatorial Pacific”. Maenhaut W, Raemdonck H, Selen A, Van Grieken R, Winchester JW, Journal of geophysical research 88, 5353 (1983). http://doi.org/10.1029/JC088IC09P05353
Abstract: By using a polyester sailboat as sampling platform, a series of duplicate aerosol samples was collected by cascade impactors on a trip from Panama to Tahiti in 1979. Elemental analysis mainly by particle-induced X ray emission (PIXE) indicated, in the samples collected between Panama and the Galapagos Islands, the presence of a substantial crustal component (∼0.4 μg/m3), fine Cu (∼0.4 ng/m3) and Zn (∼0.6 ng/m3), and excess fine S and K (∼100 and ∼2.4 ng/m3, respectively) in addition to the major sea salt elements. The crustal component and fine Cu and Zn are suggested to result from natural continental sources (i.e., eolian dust transport from the American continents and perhaps geothermal emissions). Samples collected west of the Galapagos Islands in the southern trades showed significantly lower concentrations for the nonseawater components. The average Si and Fe levels were as low as 4.8 and 3.3 ng/m3, corresponding to a maximum of 0.066 μg/m3 for an assumed mineral dust component, whereas heavy metal concentrations were all below the detection limits (typically ranging from 0.05 to 0.15 ng/m3 for V, Cr, Mn, Ni, Cu, Zn, and Se). Excess fine S decreased to a mean of 46 ng/m3, a level similar to those reported for other remote marine and continental locations. This all indicates that the marine atmosphere west of the Galapagos was little influenced by natural continental source processes or by anthropogenic emissions. Under these truly marine conditions, several concentration ratios of the major seawater elements were significantly different from those in bulk seawater. Ca, Sr, and S in >1 μm diameter particles were enriched relative to K and Na, with the enrichment being substantially more pronounced (up to 50% or higher) for l4-μm diameter particles than for particles >4 μm. Comparison of these data with a similar data set from samples collected over the Atlantic indicates that the departures from seawater composition are significantly larger for the Pacific. Differences in sea-to-air fractionation processes, probably involving binding of divalent cations to organic matter in the oceanic surface microlayer, are suggested as being responsible for these observations.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1029/JC088IC09P05353
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“Characterization of the spheroliths present in primary atypical bandkeratopathy using laser microprobe mass analysis”. Vandeputte DF, Van Grieken RE, Foets BJJ, Misotten L, Biomedical and environmental mass spectrometry 18, 753 (1989). http://doi.org/10.1002/BMS.1200180918
Abstract: Laser microprobe mass analysis was applied to study the chemical composition of spheroliths in the Bowman's membrane of patients suffering from primary atypical bandkeratopathy. The inclusions appear to consist mainly of calcium phosphate.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1002/BMS.1200180918
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“Characterization of the weathering crust of various historical buildings in Belgium”. Leysen LA, Roekens EJ, Van Grieken RE, De Geyter G, The science of the total environment 90, 117 (1990). http://doi.org/10.1016/0048-9697(90)90190-6
Abstract: A variety of samples, collected from different historical buildings and monuments throughout Belgium, were thoroughly studied, using several trace- and micro-analysis techniques. Thin sections of stones and mortar joints were characterized by means of electron probe X-ray microanalysis (EPXMA). The morphological appearance of the surface weathering crust and the possible presence of non-innate particles in the crust were elucidated using petrographical and electron microscopy. Quantitative characterization of the total chemical composition of the crust surface layer and underlying layer was performed by energy-dispersive X-ray fluorescence, and by ion chromatography and atomic absorption spectrometry for the leachable components. Special attention was also paid to the chemical composition of rain and air at the particular sampling sites. The element distribution in the transition zone between the weathering crust and the original stone material was found to vary greatly amongst the different samples analyzed. Detailed EPXMA measurements on pieces of the weathering crust showed remarkable differences in morphology and composition between the surface and the underlying layer, and provided information about the presence of fly-ash and soil dust particles in the crust. Except for crusts from the city of Brussels, which were all very high in sulphate, the samples appeared to contain very variable sulphate contents; very local micro-climate and environmental conditions at a particular site are more important in determining the weathering condition of the building stones than the local air pollution situation. Bulk analytical characterization further showed, in all the crust samples studied, a very small contribution of nitrogen- and chlorine-containing weathering products, in contrast to sulphur-containing weathering salts.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0048-9697(90)90190-6
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