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“An expert system for chemical speciation of individual particles using low-Z particle electron probe X-ray microanalysis data”. Ro C-U, Kim HK, Van Grieken R, Analytical chemistry 76, 1322 (2004). http://doi.org/10.1021/AC035149I
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/AC035149I
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“An electrochemical impedimetric aptasensing platform for sensitive and selective detection of small molecules such as chloramphenicol”. Pilehvar S, Dierckx T, Blust R, Breugelmans T, De Wael K, Sensors 14, 12059 (2014). http://doi.org/10.3390/S140712059
Abstract: We report on the aptadetection of chloramphenicol (CAP) using electrochemical impedance spectroscopy. The detection principle is based on the changes of the interfacial properties of the electrode after the interaction of the ssDNA aptamers with the target molecules. The electrode surface is partially blocked due to the formation of the aptamer-CAP complex, resulting in an increase of the interfacial electron-transfer resistance of the redox probe detected by electrochemical impedance spectroscopy or cyclic voltammetry. We observed that the ratio of polarization resistance had a linear relationship with the concentrations of CAP in the range of 1.76127 nM, and a detection limit of 1.76 nM was obtained. The covalent binding of CAP-aptamer on the electrode surface combined with the unique properties of aptamers and impedimetric transduction leads to the development of a stable and sensitive electrochemical aptasensor for CAP.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
Impact Factor: 2.677
Times cited: 34
DOI: 10.3390/S140712059
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“An adhesive conducting electrode material based on commercial mesoporous titanium dioxide as a support for Horseradish peroxidase for bioelectrochemical applications”. Rahemi V, Trashin S, Meynen V, De Wael K, Talanta : the international journal of pure and applied analytical chemistry 146, 689 (2016). http://doi.org/10.1016/J.TALANTA.2015.06.041
Abstract: An adhesive conducting electrode material containing of graphite, biocompatible ion exchange polymer nafion® and commercial mesoporous TiO2 impregnated with horseradish peroxidase (HRP) is prepared and characterized by amperometric, UVvis and N2 sorption methods. The factors influencing the performance of the resulting biosensor are studied in detail. The optimal electrode material consists of 45% graphite, 50% impregnated HRPTiO2 and 5% nafion®. The optimum conditions for H2O2 reduction are an applied potential of 0.3 V and 0.1 mM hydroquinone. Sensitivity and limit of detection in the optimum conditions are 1 A M−1 cm−2 and 1 µM correspondingly. The N2 sorption results show that the pore volume of TiO2 decreases sharply upon adsorption of HRP. The preparation process of the proposed enzyme electrode is straightforward and potentially can be used for preparation of carbon paste electrodes for bioelectrochemical detections.
Keywords: A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 4.162
Times cited: 7
DOI: 10.1016/J.TALANTA.2015.06.041
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“Amperometric flow-injection analysis of phenols induced by reactive oxygen species generated under daylight irradiation of titania impregnated with horseradish peroxidase”. Rahemi V, Trashin S, Hafideddine Z, Van Doorslaer S, Meynen V, Gorton L, De Wael K, Analytical Chemistry 92, 3643 (2020). http://doi.org/10.1021/acs.analchem.9b04617
Abstract: Titanium dioxide (TiO2) is a unique material for biosensing applications due to its capability of hosting enzymes. For the first time, we show that TiO2 can accumulate reactive oxygen species (ROS) under daylight irradiation and can support the catalytic cycle of horseradish peroxidase (HRP) without the need of H2O2 to be present in the solution. Phenolic compounds, such as hydroquinone (HQ) and 4-aminophenol (4-AP), were detected amperometrically in flow-injection analysis (FIA) mode via the use of an electrode modified with TiO2 impregnated with HRP. In contrast to the conventional detection scheme, no H2O2 was added to the analyte solution. Basically, the inherited ability of TiO2 to generate reactive oxygen species is used as a strategy to avoid adding H2O2 in the solution during the detection of phenolic compounds. Electron paramagnetic resonance (EPR) spectroscopy indicates the presence of ROS on titania which, in interaction with HRP, initiate the electrocatalysis toward phenolic compounds. The amperometric response to 4-AP was linear in the concentration range between 0.05 and 2 μM. The sensitivity was 0.51 A M–1 cm–2, and the limit of detection (LOD) 26 nM. The proposed sensor design opens new opportunities for the detection of phenolic traces by HRP-based electrochemical biosensors, yet in a more straightforward and sensitive way following green chemistry principles of avoiding the use of reactive and harmful chemical, such as H2O2.
Keywords: A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 7.4
Times cited: 3
DOI: 10.1021/acs.analchem.9b04617
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“Alteration of fossil-bearing shale (Autun, France, Permian), part II : monitoring artificial and natural ageing by combined use of S and Ca K-edge XANES analysis, Rock-Eval pyrolysis and FTIR analysis”. Odin GP, Vanmeert F, Farges F, Gand G, Janssens K, Romero-Sarmiento M-F, Steyer JS, Vantelon D, Rouchon V, Annales de paléontologie 101, 225 (2015). http://doi.org/10.1016/J.ANNPAL.2015.03.001
Abstract: Fossil-bearing shale specimens that include sulfides in their compositions are chemically reactive and sometimes also mechanically fragile. This decay is often related to iron sulfate efflorescence resulting from the oxidation of sulfide compounds. The processes underlying these degradations are poorly known, thus impeding the elaboration of curative or preventive treatments. The present contribution aims to identify the origin of museum specimen alterations. It focuses on the Flouest collection housed at the Museum National d'Histoire Naturelle (MNHN, Paris, France) and originating from the Autun Basin (Saone-et-Loire, France, Permian). To evaluate the alteration of MNHN specimens, it appeared necessary to compare their composition with that of unaltered shale so as to identify chemical changes occurring during ageing. Therefore, new material was collected in the Autun Basin, among others on the locality of Muse that corresponds to the same lithostratigraphic unit as that of the MNHN specimens. This material was, if necessary, artificially aged. The first part of this work, presented elsewhere, deals with the use of Xray diffraction and Mossbauer spectroscopy for characterizing iron reactivity and speciation. It leads to the conclusion that the reactivity of iron in the shale matrix was limited and could not account for the large efflorescence of iron (II) sulfate occurring nearby the fossil. The second part presented here focuses on the use of S K-edge X-ray Absorption Near Edge Structure (XANES) spectroscopy for characterizing sulfur speciation and reactivity. Measurements were performed on the shale matrix and on thin layers of maceral found in the proximity of damaged areas. As sulfur may be found in association with calcium or organic matter, complementary techniques were implemented, such as FTIR spectroscopy, Rock-Eval pyrolysis (characterization of organic matter content) and Ca K-edge XANES (analysis of calcium speciation) spectroscopy. It was shown that sulfur is mainly related to thioether, sulfoxide, iron sulfide, and sulfates whereas calcium is mainly bound to carboxylate, carbonate and/or sulfate groups. FTIR analysis of the macerals confirmed the presence of vitrinite on damaged MNHN specimens. The low oxygen content of new shale samples determined by Rock-Eval pyrolysis indicates that the organic matter is well preserved, despite the fact that samples come from outcrop surface. In the newly collected material, sulfur is mainly related to organic sulfides (thioether) with a minor occurrence of iron sulfide. In the shale fraction of damaged MNHN specimens, sulfur is mostly oxidized into a mixture of iron and calcium sulfate. However, in the vitrinite layers of the same specimens, a large proportion of sulfur corresponds to organic sulfides. Also the oxidation of sulfur does not occur homogeneously but preferentially in the shale fraction, probably because this latter is porous whereas vitrinite is not. Artificial ageing of new shale material showed that the oxidation of organic sulfides could be reproduced at 90 degrees C, 80% of relative humidity. However, the obtained efflorescence almost exclusively corresponds to calcium sulfate whereas iron (II) sulfates are mostly observed on MNHN specimens. The new material collected on site is probably to be questioned, and future studies will have to select new samples with fossil remains. This will be the object of the third part of this work. (C) 2015 Elsevier Masson SAS. All rights reserved.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 1.113
Times cited: 6
DOI: 10.1016/J.ANNPAL.2015.03.001
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“All crystal clear : 18th-century glass à, la façon de Bohème from the cistercian nunnery of Clairefontaine, Belgium”. Herremans D, Cagno S, Vincke A, Janssens K, De Clercq W, Journal of glass studies 55, 137 (2013)
Abstract: Excavations at the Cistercian nunnery of Clairefontaine, located near Arlon in the south of Belgium, revealed an assemblage of 18th-century colorless glass. The morphology of the vessels and the engraved decoration suggest a central European origin or, at least, stylistic inspiration. The composition of the glass points to a recipe combining silica, lime, and potash: a colorless potash glass a la facon de Boheme. This article considers the technology, morphology, and origin of the vessels. The art-historical analysis is supported by chemical research (scanning electron microscopy energy-dispersive X-ray spectroscopy [SEM-EDX]). The finds are also discussed in light of the emerging northwestern European glass industry, changing consumer practices during the 18th century, and their meaning for the inhabitants of the abbey.
Keywords: A1 Journal article; Art; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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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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“Airborne particles in the Miyagi Museum of Art in Sendai, Japan, studied by electron probe X-ray microanalysis and energy dispersive X-ray fluorescence analysis”. Injuk J, Osán J, Van Grieken R, Tsuji K, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry 18, 561 (2002). http://doi.org/10.2116/ANALSCI.18.561
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.2116/ANALSCI.18.561
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“Air-pollution-induced chemical decay of a sandy-limestone cathedral in Belgium”. Leysen L, Roekens E, Van Grieken R, The science of the total environment 78, 263 (1989). http://doi.org/10.1016/0048-9697(89)90038-7
Abstract: Different trace- and microanalytical techniques were used in an extensive study to elucidate the chemical deterioration process of the sandy-limestone St Rombouts Cathedral in Mechelen, Belgium. Samples of stones, mortar joints, slates, atmospheric aerosols and gases, total and wet deposition, and water that had run down the cathedral walls, were all thoroughly characterized. At the east side, usually not exposed to precipitation, a 3001000-μm thick outer crust of microcrystalline gypsum was observed, while at the west side, this surface layer was mostly eroded away due to precipitation. At the north and south sides, the crust contains varying amounts of gypsum and calcite. The gypsum is mostly present in a bar-shaped morphology and carbonaceous fly-ash particles were rarely found in the weathering crust. Local stone characteristics seem to be extremely important in relation to the gypsum content of the crust; black samples always have a much higher sulphate content than the corresponding white samples, irrespective of the predominant direction of orientation. The relative contribution of nitrogen- and chlorine-containing pollutants to the total decay process is much smaller than that of sulphur-containing pollutants. Deposition samples collected at the site of the cathedral mostly had a pH of > 5.6, due to the neutralization of the rainwater by alkaline atmospheric constituents. Runoff water and washdown water were enriched in all ions, especially Ca2+ and SO42−, indicating that, indeed, gypsum is the most important weathering product. The suspension in deposition samples and black-well leaching water was highly enriched in silicon-containing particles, while runoff water and white-wall leaching water contained a predominant calcium-rich suspension.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0048-9697(89)90038-7
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“Air quality monitoring in a museum for preventive conservation : results of a three-year study in the Plantin-Moretus Museum in Antwerp, Belgium”. Krupińska B, Van Grieken R, De Wael K, Microchemical journal 110, 350 (2013). http://doi.org/10.1016/J.MICROC.2013.05.006
Abstract: Through different research projects on air quality in museums, researcher and conservators try identifying various risks of air pollution on materials. The conclusions may be later translated into specific actions for a maximum preservation of the museum collections, a process known as preventive conservation. Air pollution is a particular problem in historical buildings such as museums, because they were not originally built to exhibit and protect art objects in a sustainable way. This article reports on the data and results that were obtained during 10 sampling campaigns, in the period between November 2008 and February 2012 in a museum in Antwerp (Belgium), i.e. Plantin-Moretus Museum/Print Room. Different pollutants were measured inside and outside the museum such as inorganic gases, particulate matter and black carbon. The report specifically addresses environmental factors that may be responsible for damage to the collections present in museums. Thanks to the knowledge about the current situation in the museum, accurate solutions regarding preventive conservation, in general, are suggested.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 3.034
Times cited: 46
DOI: 10.1016/J.MICROC.2013.05.006
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“Air pollution and preventive conservation in some European museums”. Van Grieken R, , 19 (2014)
Keywords: P1 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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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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“Aerosols in Santiago de Chile : a study using receptor modeling with X-ray fluorescence and single particle analysis”. Rojas CM, Artaxo P, Van Grieken R, Atmospheric environment: part B : urban atmosphere 24, 227 (1990). http://doi.org/10.1016/0957-1272(90)90028-S
Abstract: Between 15 January and 26 February 1987, 51 fine and coarse mode aerosol samples were collected at the Universidad de Santiago de Chile Planetarium using a dichotomous sampler. The samples were analyzed by X-ray fluorescence for up to 17 elements (Mg, Al, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb). Aerosol particles were individually studied by Electron Probe Microanalysis (EPMA) and Laser Microprobe Mass Analysis (LAMMA). The data set consisting of aerosol elemental concentrations and meteorological variables was subjected to Principal Factor Analysis (PFA), allowing the identification of six fine mode particle source classes (soil, industrial, sulfate particles, traffic, residual oil, wood-burnings), and five coarse mode particle source classes (soil, industrial, traffic, residual oil, sulfate particles). Both PFA solutions explained about 81 and 90% of the total variance in the data set, respectively. The regression of elemental mass concentrations on the Absolute Principal Factor Scores allowed the estimation of the contribution of the different source classes to the Santiago aerosol. Within the fine fraction, secondary SO42− particles were responsible for about 49% of the fine mode aerosol mass concentration, while 26, 13, 6.4 and 5.6% were attributed to wood-burning/car exhausts, residual oil combustion, soil dust/metallurgical, and soil dust/wood-burning releases, respectively. The coarse fraction source apportionment was mainly dominated by soil dust, accounting for 74% of the coarse mode aerosol mass concentration. A composite of soil dust and industrial release accounted for 13%; a composite of secondary sulfates contributed with 9%; a composite of soil dust and automotive emissions, and secondary sulfates were responsible for 4 and 0.03% of the coarse aerosol mass concentration, respectively. EPMA results are in satisfactory agreement with those from the bulk analysis and allowed the identification of eight particle types in both fine and coarse mode aerosols, pertaining to different source classes, namely soil, seaspray, secondary SO42−, metallurgical emissions and biomass burning release. EPMA also evidenced that one of the most abundant particle types corresponded to marine aerosol, having an average diameter of 0.7 μm for the fine mode and 2.2 μm for the coarse mode aerosol. LAMMA results indicate that, in fact, seaspray has been transported into the city of Santiago de Chile airshed, suffering several transformations and a sulfur enrichment. This analytical technique also provided evidence of the abundance of carbon-rich particles, which were not detected by either the bulk X-ray analysis or EPMA; they are probably due to fossil-fuel combustion releases.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0957-1272(90)90028-S
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“Aerosol-soil fractionation for Namib Desert samples”. Eltayeb MAH, Van Grieken RE, Maenhaut W, Annegarn HAJ, Atmospheric environment: part A : general topics 27, 669 (1993). http://doi.org/10.1016/0960-1686(93)90185-2
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0960-1686(93)90185-2
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“Aerosol-soil fractionation for Namib desert samples”. Eltayeb MAH, Van Grieken RE, Maenhaut W, Annegarn HAJ, Journal of aersol science 23, 983 (1992)
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Aerosol composition studies using accelerator proton bombardment”. Van Grieken R, (1974)
Keywords: P3 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Aerosol composition as a function of particle size”. Koleleni YIA, Van Grieken R, Tanzanian journal of science 19, 49 (1993)
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Aerosol characteristics and sources for the Amazon Basin during the wet season”. Artaxo P, Maenhaut W, Storms H, Van Grieken R, Journal of geophysical research 95, 16971 (1990). http://doi.org/10.1029/JD095ID10P16971
Abstract: As a part of the NASA Global Tropospheric Experiment (GTE), aerosols were sampled in the tropical rain forest of the Amazon Basin during the Amazon Boundary Layer Experiment (ABLE 2B) in April and May 1987, in the wet season, when no forest burning occurs. Fine (dp < 2.0 μm) and coarse (2.0 < dp < 15 μm) aerosol fractions were collected using stacked filter units, at three sites under the forest canopy and at three levels of a tower inside the jungle. Particle-induced X ray emission (PIXE) was used to measure concentrations of 22 elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Zr, and Pb). Morphological and trace element measurements of individual particles were carried out by automated electron probe X ray microanalysis. Gravimetric analysis was performed to obtain the fine and coarse aerosol mass concentration. Absolute factor analysis was used to interpret the large data set of the trace element concentrations and to obtain elemental source profiles. Hierarchical cluster analysis was used to derive groups of individual particles. The concentrations of soil dust related elements (Al, Si, Ti, Fe, Mn) were 5 times larger in the wet season compared to the 1985 ABLE 2A dry season experiment. Biogenic aerosol related elements in the fine fraction showed lower concentrations in the wet season. Fine aerosol mass concentration averaged only 2.1±0.7 μg m−3, while the average coarse mass concentration was 6.1±1.8 μg m −3. Sulphur concentrations averaged 76±14 ng m −3 in the fine fraction and 37±9 ng m −3 in the coarse fraction. Biogenic aerosol-related elements were dominant under the forest canopy, while soil dust dominated at the top of the forest canopy. Only two factors explained about 90% of the data variability for the fine and coarse aerosol fractions. These were soil dust (represented mainly by Al, Si, Ti, Mn, and Fe) and biogenic aerosol (represented by K, P, Cl, S, Zn, and the aerosol mass concentration). Source profiles showed a homogeneous aerosol distribution with similar elemental compositions at the different sampling sites. Enrichment factor calculations revealed a soil dust elemental profile similar to the average bulk soil composition, and a biogenic component similar to the plant bulk elemental composition. Total aerosol mass source apportionment showed that biogenic particles account for 5595% of the airborne concentrations. The analysis of individual aerosol particles showed that the biogenic particles consist of leaf fragments, pollen grains, fungi, algae, and other types of particles. Several groups of particles with K, Cl, P, S, and Ca as minor elements could easily be identified as biogenic particles on the basis of their morphology. Considering the vast area of tropical rain forests and the concentrations measured in this work, it is possible that biogenic particles can play an important role in the global aerosol budget and in the global biogeochemical cycles of various elements.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1029/JD095ID10P16971
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“Advantages of combined mu-XRF and mu-XRD for phase characterization of Ti-B-C ceramics compared with conventional X-ray diffraction”. Jaroszewicz J, de Nolf W, Janssens K, Michalski A, Falkenberg G, Analytical and bioanalytical chemistry 391, 1129 (2008). http://doi.org/10.1007/S00216-008-2097-6
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 3.431
Times cited: 7
DOI: 10.1007/S00216-008-2097-6
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Legrand S (2021) Advanced chemical imaging of artworks. 315 p
Abstract: Last century the field of heritage sciences expanded beyond imagination. The inventions of X-ray radiography and infrared reflectography allowed experts to investigate paintings below the surface as well. More recent developments led to the advent of the field of hyperspectral imaging, to which the advanced chemical imaging methods, used in this thesis work, belong. These techniques not only allow to identify the components present in artworks, but also to visualize their distribution over these objects. The resulting distribution maps permit a broader public to interpret the scientific data and to relate these results with the artwork itself. During this thesis work a range of flat artworks were investigated in a non-destructive manner using mainly two macroscopic imaging techniques: macroscopic X-ray fluorescence scanning and macroscopic Fourier transformed mid-infrared scanning in reflectance mode. The resulting images were sometimes supplemented with microscopic techniques on a minute selection of samples to fully understand the layer build-up, composition and distribution of these materials over the stratigraphy. Illuminated manuscripts pushed the interpretation of the macroscopic imaging techniques: due to the impossibility of sampling, all answers had to be obtained non-destructively. Documenting masterpieces such as the Ghent Altarpiece by means of chemical imaging techniques, helped the restoration team, assisted by the international commission to make the daring decision of manually removing the non-original paint layers. Scanning stained-glass windows allowed experts to document the panels, create situation reports, identify later infills and guide the restoration process in a more efficient manner. By initially applying non-destructive imaging techniques, many of the research/conservation questions could already be answered. Based on the resulting distribution maps, only a very limited amount of sampling was required to obtain a representative set to answer the remaining questions. In most cases the combination of multiple methods was necessary to fully understand the situation. A similar trend could be seen in the research field: the collaboration between divergent disciples was often required in order to explain all observations. In order to completely break through, the scanning speed of these techniques has to increase even more in order to cover an acceptable surface in one workday. Parallel with the operational speed, the (basic) data treatment should also be streamlined more in order to allow a broader user group to access the results. Once these two improvements are carried out, these techniques become accessible to a larger public.
Keywords: Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Acute changes in pulse pressure in relation to constituents of particulate air pollution in elderly persons”. Jacobs L, Buczyńska A, Walgraeve C, Potgieter-Vermaak S, Van Grieken R, et al, Environmental research 117, 60 (2012). http://doi.org/10.1016/J.ENVRES.2012.05.003
Abstract: An increased pulse pressure (difference between systolic and diastolic blood pressure) suggests aortic stiffening. The objective of this study was to examine the acute effects of both particulate matter (PM) mass and composition on blood pressure, among elderly persons. We carried out a panel study in persons living in elderly homes in Antwerp, Belgium. We recruited 88 non-smoking persons, 70% women with a mean age of 83 years (standard deviation: 5.2). Blood pressure was measured and a blood sample was collected on two time points, which were chosen so that there was an exposure contrast in ambient PM exposure. The elemental content of the collected indoor and outdoor PM2.5 (particulate matter with an aerodynamic diameter <2.5 μm) mass concentration was measured. Oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) on outdoor PM10 (particulate matter with an aerodynamic diameter <10 μm) were measured. Each interquartile range increase of 20.8 μg/m³ in 24-h mean outdoor PM2.5 was associated with an increase in pulse pressure of 4.0 mmHg (95% confidence interval: 1.86.2), in persons taking antihypertensive medication (n=57), but not in persons not using antihypertensive medication (n=31) (p for interaction: 0.02). Vanadium, iron and nickel contents of PM2.5 were significantly associated with systolic blood pressure and pulse pressure, among persons on antihypertensive medication. Similar results were found for indoor concentrations. Of the oxy-PAHs, chrysene-5,6-dione and benzo[a]pyrene-3,6-dione were significantly associated with increases in systolic blood pressure and pulse pressure. In elderly, pulse pressure was positively associated with acute increases in outdoor and indoor air pollution, among persons taking antihypertensive medication. These results might form a mechanistic pathway linking air pollution as a trigger of cardiovascular events.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.ENVRES.2012.05.003
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“Accurate evaluation of \mu-PIXE and \mu-XRF spectral data through iterative least squares fitting”. Janssens K, Vekemans B, Adams F, van Espen P, Mutsaers P, Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms
T2 –, 7th International Conference on Particle Induced X-ray Emission and Its Analytical Applications, MAY 26-30, 1995, Abano Terme, Italy 109, 179 (1996). http://doi.org/10.1016/0168-583X(95)01211-7
Abstract: The integration of the nonlinear least squares X-ray spectrum evaluation progam AXIL. into a mu-PIXE and a mu-XRF setup is discussed. The use of the software when procesing data sets derived from biological and geological samples is described.
Keywords: A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
DOI: 10.1016/0168-583X(95)01211-7
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“Accelerated microstructural evolution of a calcium-silicate-hydrate (C-S-H) phase in pozzolanic pastes using fine siliceous sources: comparison with historic pozzolanic mortars”. Moropoulou A, Cakmak A, Labropoulos KC, Van Grieken R, Torfs K, Cement and concrete research 34, 1 (2004). http://doi.org/10.1016/S0008-8846(03)00187-X
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/S0008-8846(03)00187-X
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“Accelerated ageing of shales of palaeontological interest : impact of temperature conditions”. Odin GP, Vanmeert F, Janssens K, Lelièvre H, Mertz J-D, Rouchon V, Annales de paléontologie 100, 137 (2014). http://doi.org/10.1016/J.ANNPAL.2013.12.002
Abstract: The palaeontological collections of the Muséum national dHistoire naturelle (MNHN, Paris, France) and the Muséum dHistoire naturelle dAutun (MHNA, Autun, France) include many fossil specimens originating from the argillaceous shales of the Autun basin (Saône-et-Loire, France). These fossils are preserved within sedimentary rocks containing unstable sulphide compounds, such as pyrite, which may deteriorate in contact with water and oxygen. This alteration provokes crystalline efflorescence and cracks, thus compromising the preservations of the fossils. This work constitutes the first step of a project that aims to understand the mechanisms of alteration of these materials in order to define conservation guidelines for palaeontological collections. For this purpose, eight damaged specimens originating from the Permian Autun basin (Saône-et-Loire, France) were selected and analyzed by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy coupled to energy dispersive X-ray spectrometry (SEM/EDS) and X-ray absorption spectroscopy at the threshold of the sulphur Kα-edge (XANES). This methodology enabled the characterization of the matrices composition and the chemical nature of the alterations. Subsequently, we have sought to reproduce by artificial ageing the alteration phenomena encountered in the collections. New shale samples were collected on seven outcrops of the same Autun basin. They were analyzed and subjected to artificial ageing at 50% relative humidity (RH) and at temperatures ranging between 40 °C and 90 °C. Our work shows that damaged specimens and newly collected shale have a similar mineralogical composition. Yet the crystalline efflorescence material formed on the surface of damaged specimens belongs to the iron sulphate group whereas gypsum predominates on artificially aged shale samples. Reproducing the alterations observed on specimens by artificial ageing remains therefore problematic. Additionally, it appears that the temperature of ageing controls the nature of the damage: at 40 °C, many samples are mechanically damaged whereas no or minor crystalline efflorescence occurs. At 90 °C, it is the opposite tendency that is observed. Finally, mechanical damages do not seem to be correlated with the development of the efflorescence: samples with efflorescent crystals generally do not show clearly visible cracks; those that seem most fragmented do not show any visible efflorescence.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 1.113
Times cited: 5
DOI: 10.1016/J.ANNPAL.2013.12.002
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“Absorption correction via scattered radiation in energy-dispersive X-ray fluorescence analysis for samples of variable composition and thickness”. Van Dyck PM, Van Grieken RE, Analytical chemistry 52, 1859 (1980). http://doi.org/10.1021/AC50062A020
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/AC50062A020
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“Absorption correction in electron probe x-ray microanalysis of thin samples”. Markowicz AA, Storms HM, Van Grieken RE, Analytical chemistry 58, 1282 (1986). http://doi.org/10.1021/AC00298A003
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/AC00298A003
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“Absorption correction for X-ray-fluorescence analysis of aerosol loaded filters”. Adams FC, Van Grieken RE, Analytical chemistry 47, 1767 (1975). http://doi.org/10.1021/AC60361A040
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/AC60361A040
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“A XANES study of chromophores : the case of black glass”. Ceglia A, Nuyts G, Cagno S, Meulebroeck W, Baert K, Cosyns P, Nys K, Thienpont H, Janssens K, Terryn H, Analytical methods 6, 2662 (2014). http://doi.org/10.1039/C3AY42029A
Abstract: We studied the Fe K-edge X-ray absorption near edge (XANES) spectra of several Roman black glass fragments in order to determine the Fe3+/ΣFe ratio of these materials. The selected archaeological glass samples cover the period 1st5th century AD in nine different sites of the North Western provinces of the Roman Empire. The fragments belong to two different compositional groups demonstrating a diachronic evolution: early Roman HMG (High Magnesia Glass) and Roman Imperial LMG (Low Magnesia Glass). The first group contains natural Fe levels (below 2 wt% as Fe2O3), while the LMG has concentrations above 5 wt%. This difference is also reflected by Fe3+/ΣFe values. Low iron glass was produced under strongly reducing conditions in order to obtain the black colour, with average Fe3+/ΣFe values ≈ 0.17. LMG glass is somewhat more oxidised (Fe3+/ΣFe ≈ 0.40.5). While HMG glass required active control of the furnace environment, LMG was made under ambient atmosphere and its higher oxidation degree is mainly determined by the chemistry of the raw glass.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 1.9
Times cited: 14
DOI: 10.1039/C3AY42029A
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“A survey of the recent use of x-ray beam methods for non-destructive investigations in the cultural heritage sector”. Janssens K page 265 (2005).
Keywords: H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“A survey of occupational exposure to inhalable wood dust among workers in small- and medium-scale wood-processing enterprises in Ethiopia”. Ayalew E, Gebre Y, De Wael K, The annals of occupational hygiene 59, 253 (2015). http://doi.org/10.1093/ANNHYG/MEU086
Abstract: A study of wood dust exposure in 20 small- and medium-scale wood-processing enterprises was performed in Ethiopia. Sampling was conducted daily from January to June, 2013 and a total of 360 samples from 113 workers were collected with Institute of Occupational Medicine (IOM) personal samplers. Eight-hour time-weighted average exposure to wood dust ranged from 0.24 to 23.3mg m−3 with a geometric mean (GM) of 6.82mg m−3 and a geometric standard deviation of 1.82. Although Ethiopia did not have any defined standard of Occupational Exposure Limit for wood dust exposure, 71% of the measurements exceeded the limit of 5mg m−3 set by the European Union (EU). Higher than the EU exposure limit was measured while workers perform sanding and sawing activities with a GM of 9.72 and 7.60mg m−3, respectively. In conclusion, wood workers in the small- and medium-scale enterprises are at a higher risk of developing different respiratory health problems with continuous exposure trends.
Keywords: A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 1.71
Times cited: 4
DOI: 10.1093/ANNHYG/MEU086
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