“Characterization of the ionic and particulate systems in the reservoir”. Godoi RHM, Lima Bittencourt AV, Hirata PY, Jafelicci Junior M, dos Reis Neto JM, Van Grieken R page 143 (2014).
Keywords: H2 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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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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“Characterization of Yenisey River U-particles using a combination of μ-XRF, μ-XRD and U-LIII μ-XANES”. Lind OC, Claussen-Kjerre L, de Nolf W, Falkenberg G, Jaroszewicz J, Janssens K, Salbu B page 1279 (2008).
Keywords: H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Charakterystyka i wpływ zanieczyszczeń, powietrza na eksponaty w muzeach”. Kontozova-Deutsch V, Deutsch F, Krata A, Van Grieken R, Análityka , 64 (2008)
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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Sabzalipour A (2021) Charge transport in magnetic topological insulators. xiv, 185 p
Abstract: Novel quantum phases of matter and developing practical control over their characteristics is one of the primary aims of current condensed matter physics. It offers the potential for a new generation of energy, electronic and photonic technologies. Among all the newly found phases of matter, topological insulators are novel phases of quantum matter with fascinating bulk band topology and surface states protected by specific symmetries. For example, at the boundary of a strong topological insulator and a trivial insulator, metallic surface states appear that are protected by time-reversal symmetry. As a result, the bulk continues to be insulating, while the surface can support exotic high-mobility spin-polarized electronic states. Since there is no such thing as a clean system, impurities and other disorders are always present in materials. Even while impurities appear to be unfavorable to a system at first look, doping the host system with impurities allows us to engineer different electronic properties of systems, such as the Fermi level or electron density. Because of the symmetry protected metallic states in topological insulators, charge transport responds distinctively to magnetic and non-magnetic impurities. This doctoral dissertation explores how the longitudinal charge transport in magnetic topological thin films and the anomalous Hall effect on the surface of 3D magnetic topological insulators is influenced by point-like and randomly distributed dilute magnetic impurities. We are interested in how charge transport in these systems responds to the orientation of the magnetization orientation and how this response evolves based on the system's main characteristics, such as the magnitude of the Fermi level or gate voltage. Because topological insulators have a strong spin-orbit coupling, the interaction between conducting electrons and local magnetic impurities is very anisotropic. We will show that this anisotropy even enhances when magnetic topological thin films are exposed to a substrate or gate voltage. Therefore, to properly capture this anisotropy in charge transport calculations, we rely on a generalized Boltzmann formalism together with a modified relaxation time scheme. We show that magnetic impurities affect the charge transport in topological insulators by inducing a transition selection rule that governs scatterings of electrons between various electronic states. We see that this selection rule is highly sensitive to the spin direction of the magnetic impurities as well as the position of the Fermi level. According to this selection rule and depending on the position of the Fermi level, two different transport regimes are realized in magnetic topological thin films. In one of these regimes, our findings show that a dissipation less charge current can be generated. In other words, even if there are many magnetic impurities in the system, electrons do not notice them and, remarkably, conduct charge without dissipation. Outside this regime, the charge transport is always dissipative and its sensitivity to the spatial orientation of the magnetic impurities can be effectively modulated by a substrate or gate voltage. In this doctoral thesis, we also explore the anomalous Hall effect (AHE) on the surface of 3D magnetic topological insulators. The AHE is generated by three mechanisms: the intrinsic effect (owing to a nonzero Berry curvature), the side jump effect, and the skew scattering effect. They compete to dominate the AHE in distinct regimes. Analytically, we calculate the contributions of all three mechanisms to the scattering of massive Dirac fermions by magnetic impurities. Our results reveal three transport regimes based on the relative importance of the engaged mechanisms. The identification of these three distinctive transport regimes can assist experimentalists in achieving a regime in which each contribution is dominant over the others, allowing them to measure them separately. Typically, this is not feasible empirically since the total value of the experimentally observed AHE conceals the specific information of each of the three contributions. Based on our analytical calculations, we prove that the AHE can change sign by varying the orientation of the surface magnetization, the concentration of impurities, and the location of the Fermi level, which is consistent with previous experimental findings. In addition, we show that by suitably adjusting the given parameters, any contribution to the AHE, or even the entire AHE, can be turned off. For example, in a system with in-plane magnetization, one can turn off the AHE by pushing the system into the completely metallic regime. Furthermore, we demonstrate that any contribution to the AHE, or even the whole AHE, can be turned off by appropriately changing the provided parameters. For example, in a system with in-plane magnetization, the AHE can be turned off by pushing the system into the fully metallic regime.
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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“Charged-impurity correlations in a δ-doped quantum barrier”. Koenraad PM, Shi JM, van de Stadt AFW, Smets A, Perenboom JAAJ, Peeters FM, Devreese JT, Wolter JH, , 2351 (1996)
Keywords: P3 Proceeding; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
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“Charged-impurity correlations in Si ?-doped GaAs”. Shi JM, Koenraad PM, van de Stadt AFW, Peeters FM, Devreese JT, Wolter JH, , 2351 (1996)
Keywords: P3 Proceeding; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
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“Chelating 2,2′-diaminodiethylamine cellulose filters and X-ray fluorescence for preconcentration and trace analysis of natural waters”. Smits J, Van Grieken R, International journal of environmental analytical chemistry 9, 81 (1981). http://doi.org/10.1080/03067318108071902
Abstract: The 2,2′-diaminodiethylamine (DEN) functional group can be expected to have ideal properties for the chelation of transition metals and their collection from aqueous solutions, independent of the alkali and alkaline earth ions concentration. Introducing DEN into cellulose filters allows straightforward preconcentration of trace cations by a simple filtration step, and the DEN-filter constitutes a suitable target for X-ray fluorescence (XRF) analysis. The linearity between the XRF-response on the loaded DEN-filter and the trace cation concentration in the solution appears excellent, up to a total filter capacity of ca. 3 μeq.cm−2. The detection limits are around 0.5 μg. l−1 in most practical cases. Accuracy and precision are around 10%. The applicability of the proposed procedure is illustrated on a comparative basis by XRF-analysis of drinking water and surface water, after preconcentration by DEN-filtration and by alternative procedures.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/03067318108071902
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“Chelex-100 ion-exchange filter membranes for preconcentration in x-ray-fluorescence analysis of water”. Van Grieken RE, Bresseleers CM, Vanderborght BM, Analytical chemistry 49, 1326 (1977). http://doi.org/10.1021/AC50017A011
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/AC50017A011
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“Chemical alteration and colour changes in the Amsterdam sunflowers”. Monico L, Hendriks E, Geldof M, Miliani C, Janssens K, Brunetti BG, Cotte M, Vanmeert F, Chieli A, Van der Snickt G, Romani A, Melo MJ page 125 (2019).
Abstract: This chapter provides a description of colour changes in the Amsterdam Sunflowers due to chemical alteration of pigments, with a focus on geranium lakes and chrome yellows. The brilliant and forceful colours of these and other late nineteenth-century synthetic materials offered artists such as Vincent van Gogh new means of artistic expression that exploited a range of contrasting hues and tints. However, geranium lakes have a strong tendency to fade and chrome yellows to darken under the influence of light. Van Gogh, like other artists of his day, was aware of this drawback, yet he continued to favour the use of both pigments up until his death in July 1890 due to the unparalleled effects they gave. In April 1888, Vincent wrote to his brother Theo: Van Gogh's use of unstable colours opens a series of questions regarding the extent to which colour change affects the way his paintings look today, as discussed here in relation to the Amsterdam Sunflowers. Furthermore, given the frequency with which geranium lakes and chrome yellows occur in Van Gogh's paintings of the period 1888–90 and the predominance of chrome yellows in Sunflowers, it becomes important to understand the factors that can drive these processes of deterioration in order to develop appropriate strategies for conserving the artist's works.
Keywords: H1 Book chapter; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
DOI: 10.1017/9789048550531.006
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“Chemical analysis in metal processing: overview and future needs in refined and ultrapure metals”. Gijbels R, Acta technica Belgica: metallurgie 30, 91 (1991)
Keywords: A3 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
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“Chemical analysis of the powder deposit on Chinese jade objects”. Aerts A, Janssens K, Adams F page 12 (1995).
Keywords: H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical characterisation of weathering crust and run-off water for a deteriorated limestone cathedral”. Roekens E, Leysen L, Van Grieken R, Komy Z, (1986)
Keywords: P3 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical characterisation, source identification and quantification of the input of atmospheric particulate matter into the North Sea”. van Malderen H, de Bock L, Hoornaert S, Injuk J, Van Grieken R page 103 (1996).
Keywords: H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical characterization and multivariate analysis of atmospheric PM2.5 particles”. Ravindra K, Stranger M, Van Grieken R, Journal of atmospheric chemistry 59, 199 (2008). http://doi.org/10.1007/S10874-008-9102-5
Abstract: The new European Council Directive (PE-CONS 3696/07) frames the inhalable (PM10) and fine particles (PM2.5) on priority to chemically characterize these fractions in order to understand their possible relation with health effects. Considering this, PM2.5 was collected during four different seasons to evaluate the relative abundance of bulk elements (Cl, S, Si, Al, Br, Cu, Fe, Ti, Ca, K, Pb, Zn, Ni, Mn, Cr and V) and water soluble ions (F−, Cl−, NO2 −, NO3 −, SO4 2−, Na+, NH4 +, Ca2+ and Mg2+) over Menen, a Belgian city near the French border. The air quality over Menen is influenced by industrialized regions on both sides of the border. The most abundant ionic species were NO3 −, SO4 2− and NH4 +, and they showed distinct seasonal variation. The elevated levels of NO3 − during spring and summer were found to be related to the larger availability of the NOx precursor. The various elemental species analyzed were distinguished into crustal and anthropogenic source categories. The dominating elements were S and Cl in the PM2.5 particles. The anthropogenic fraction (e.g. Zn, Pb, and Cu) shows a more scattered abundance. Furthermore, the ions and elemental data were also processed using principal component analysis and cluster analysis to identify their sources and chemistry. These approach identifies anthropogenic (traffic and industrial) emissions as a major source for fine particles. The variations in the natural/anthropogenic fractions of PM2.5 were also found to be a function of meteorological conditions as well as of long-range transport of air masses from the industrialized regions of the continent.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S10874-008-9102-5
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“Chemical characterization and source apportionment of fine aerosols”. Ravindra K, Stranger M, Van Grieken R, Sokhi RS (2009).
Keywords: H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical characterization of airborne particles in St. Martinus Cathedral in Weert, The Netherlands”. Spolnik Z, Worobiec A, Injuk J, Neilen D, Schellen H, Van Grieken R, Microchimica acta 145, 223 (2004). http://doi.org/10.1007/S00604-003-0158-2
Keywords: A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1007/S00604-003-0158-2
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“Chemical characterization of airborne particulate matter above the North Sea”. Bruynseels F, Storms H, Van Grieken R, (1985)
Keywords: P3 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical characterization of individual aerosol particles from remote and polluted marine air”. Bruynseels F, Storms H, Van Grieken R, (1985)
Keywords: P3 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical characterization of individual aerosol particles in Central Siberia”. van Malderen H, Van Grieken R, Bufetov NV, Koutzenogii KP, Environmental science and technology 30, 312 (1996). http://doi.org/10.1021/ES950402K
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1021/ES950402K
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Horemans B (2012) Chemical characterization of particulate air pollutants : case studies on indoor air quality, cultural heritage and the marine environment. 229 p
Keywords: Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical composition and mass closure of particulate matter at six urban sites in Europe”. Sillanpää, M, Hillamo R, Saarikoski S, Frey A, Pennanen A, Makkonen U, Spolnik Z, Van Grieken R, Brani&scaron, M, Brunekreef B, Chalbot M-C, Kuhlbusch T, Sunyer J, Kerminen V-M, Kulmala M, Salonen RO, Atmospheric environment : an international journal 40, S212 (2006). http://doi.org/10.1016/J.ATMOSENV.2006.01.063
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.ATMOSENV.2006.01.063
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Schalm O, Caen J, Janssens K (2007) Chemical composition of 19th century window glass originating from stianed glass windows located in Belgium. 169–178
Keywords: P2 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical composition of atmospheric aerosols sampled worldwide”. Van Grieken R, Maenhaut W, Winchester JW, National Geographic Society research reports 20, 791 (1985)
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical composition of building materials used in Turkey”. Čevik U, Damla N, Van Grieken R, Vefa Akpinar M, Construction and building materials 25, 1546 (2011). http://doi.org/10.1016/J.CONBUILDMAT.2010.08.011
Abstract: The main goal of this work was to determine the chemical composition of building materials used in Turkey by utilizing energy dispersive X-ray fluorescence (EDXRF) spectrometry. Gas concrete, cement, sand, bricks, roofing tiles, marble, lime and gypsum materials were selected as building materials for this research. The chemical contents and their trace concentrations of the selected samples were determined. The most abundant oxides measured were generally SiO2, Al2O3, CaO, MgO, Fe2O3, K2O and SO3 for all samples. While the main chemical component of gas concrete, cement, sand and marble samples were SiO2 and CaO, brick and roofing tile mainly consisted of SiO2 and Al2O3. CaO and SO3 were major component of lime and gypsum samples, respectively. For U and Th concentrations in the samples, activities of 226Ra and 232Th were measured by utilizing gamma spectrometry. ANOVA and Pearson correlation analyses were performed on the studied data for statistical analysis.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.CONBUILDMAT.2010.08.011
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“Chemical composition of river sediments from the Indian sub-continent”. Subramanian V, Van 't dack L, Van Grieken R, Chemical geology 48, 271 (1985). http://doi.org/10.1016/0009-2541(85)90052-X
Abstract: River sediments from all of the major drainage basins (except the Indus) in the Indian sub-continent were collected and analysed by thin-film X-ray fluorescence technique (XRF) to determine their chemical composition. On the basis of analysis of more than 120 samples, average chemical compositions of river-borne sediments from the Indian sub-continent have been calculated. Also, average concentration values for sediments from each of the river basins, and the sub-continent average and the inter-basin differences are discussed in relation to weathering processes in the drainage basins. Comparisons have been made with the chemistry of sediments from the Bay of Bengal (which receives the bulk of sediments delivered by Indian rivers). Our observations are discussed in the light of average chemical composition of world-river sediments and the world surface rock exposed for continental weathering.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/0009-2541(85)90052-X
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“Chemical composition of riverine suspended matter and sediments from the Indian sub-continent”. Dekov V, Subramanian V, Van Grieken R, Mitteilungen aus dem Geologisch-Paläontologischen Institut der Universität Hamburg 82, 99 (1999)
Keywords: A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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“Chemical composition of sediments and suspended matter from the Cauvery and Brahmaputra rivers (India)”. Dekov VM, Araujo F, Van Grieken R, Subramanian V, The science of the total environment 212, 89 (1998). http://doi.org/10.1016/S0048-9697(97)00132-0
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/S0048-9697(97)00132-0
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“Chemical composition of sediments and suspended matter from the Cauvery and Brahmaputra rivers (India)”. Dekov VM, Araujo F, Van Grieken R, Subramanian V, The science of the total environment 203, 51 (1997)
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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