“Computer simulations of a dielectric barrier discharge used for analytical spectrometry”. Martens T, Bogaerts A, Brok W, van Dijk J, Analytical and bioanalytical chemistry 388, 1583 (2007). http://doi.org/10.1007/s00216-007-1269-0
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.431
Times cited: 28
DOI: 10.1007/s00216-007-1269-0
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“Atomic spectroscopy”. Bings NH, Bogaerts A, Broekaert JAC, Analytical chemistry 80, 4317 (2008). http://doi.org/10.1021/ac8006297
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 6.32
Times cited: 53
DOI: 10.1021/ac8006297
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“Expansion of laser-generated plumes near the plasma ignition threshold”. Balazs L, Gijbels R, Vertes A, Analytical chemistry 63, 314 (1991)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 5.636
Times cited: 71
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“Optimized transport setup for high repetition rate pulse-separated analysis in laser ablation-inductively coupled plasma mass spectrometry”. Lindner H, Autrique D, Garcia CC, Niemax K, Bogaerts A, Analytical chemistry 81, 4241 (2009). http://doi.org/10.1021/ac802627x
Abstract: An optimized laser ablation setup, proposed for high repetition rate inductively coupled plasma mass spectrometry (ICPMS) analyses such as 2D imaging or depth profiling, is presented. For such applications, the particle washout time needs to be as short as possible to allow high laser pulse frequencies for reduced analysis time. Therefore, it is desirable to have an ablation setup that operates as a laminar flow reactor (LFR). A top-down strategy was applied that resulted in the present design. In the first step, a previously applied ablation setup was analyzed on the basis of computational fluid dynamics (CFD) results presented by D. Autrique et al. (Spectrochim. Acta, B 2008, 63, 257−270). By means of CFD simulations, the design was modified in such a way that it operated in the LFR regime. Experimental results demonstrate that the current design can indeed be regarded as an LFR. Furthermore, the operation under LFR conditions allowed some insight into the initial radial concentration distribution if the experimental ICPMS signal and analytical expressions are taken into account. Recommendations for a modified setup for more resilient spatial distributions are given. With the present setup, a washout time of 140 ms has been achieved for a 3% signal area criterion. Therefore, 7 Hz repetition rates can be applied with the present setup. Using elementary formulas of the analytical model, an upper bound for the washout times for similar setups can be predicted. The authors believe that the presented setup geometry comes close to the achievable limit for reliable short washout times.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 6.32
Times cited: 18
DOI: 10.1021/ac802627x
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“Theoretical characterization of an atmospheric pressure glow discharge used for analytical spectrometry”. Martens T, Mihailova D, van Dijk J, Bogaerts A, Analytical chemistry 81, 9096 (2009). http://doi.org/10.1021/ac9017742
Abstract: We have investigated the plasma processes in an atmospheric pressure glow discharge (APGD) in He used for analytical spectrometry by means of fluid and Monte Carlo (MC) simulations. Typical results include the potential and electric field distributions in the plasma, the density profiles of the various plasma species throughout the discharge, the mean electron energy, as well as the rates of the various collision processes in the plasma, and the relative importance of the different production and loss rates for the various species. The similarities and differences with low-pressure glow discharges are discussed. The main differences are a very small cathode dark space region and a large positive column as well as the dominant role of molecular ions. Some characteristic features of the APGD, such as the occurrence of the different spatial zones in the discharge, are illustrated, with links to experimental observations.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 6.32
Times cited: 15
DOI: 10.1021/ac9017742
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“Atomic spectroscopy: a review”. Bings NH, Bogaerts A, Broekaert JAC, Analytical chemistry 82, 4653 (2010). http://doi.org/10.1021/ac1010469
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 6.32
Times cited: 65
DOI: 10.1021/ac1010469
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“Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples”. Monico L, van der Snickt G, Janssens K, de Nolf W, Miliani C, Verbeeck J, Tian H, Tan H, Dik J, Radepont M, Cotte M, Analytical chemistry 83, 1214 (2011). http://doi.org/10.1021/ac102424h
Abstract: On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 6.32
Times cited: 113
DOI: 10.1021/ac102424h
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“Simulation and experimental studies on plasma temperature, flow velocity, and injector diameter effects for an inductively coupled plasma”. Lindner H, Murtazin A, Groh S, Niemax K, Bogaerts A, Analytical chemistry 83, 9260 (2011). http://doi.org/10.1021/ac201699q
Abstract: An inductively coupled plasma (ICP) is analyzed by means of experiments and numerical simulation. Important plasma properties are analyzed, namely, the effective temperature inside the central channel and the mean flow velocity inside the plasma. Furthermore, the effect of torches with different injector diameters is studied by the model. The temperature inside the central channel is determined from the end-on collected line-to-background ratio in dependence of the injector gas flow rates. Within the limits of 3% deviation, the results of the simulation and the experiments are in good agreement in the range of flow rates relevant for the analysis of relatively large droplets, i.e., 50 μm. The deviation increases for higher gas flow rates but stays below 6% for all flow rates studied. The velocity of the gas inside the coil region was determined by side-on analyte emission measurements with single monodisperse droplet introduction and by the analysis of the injector gas path lines in the simulation. In the downstream region significantly higher velocities were found than in the upstream region in both the simulation and the experiment. The quantitative values show good agreement in the downstream region. In the upstream region, deviations were found in the absolute values which can be attributed to the flow conditions in that region and because the methods used for velocity determination are not fully consistent. Eddy structures are found in the simulated flow lines. These affect strongly the way taken by the path lines of the injector gas and they can explain the very long analytical signals found in the experiments at low flow rates. Simulations were performed for different injector diameters in order to find conditions where good analyte transport and optimum signals can be expected. The results clearly show the existence of a transition flow rate which marks the lower limit for effective analyte transport conditions through the plasma. A rule-of-thumb equation was extracted from the results from which the transition flow rate can be estimated for different injector diameters and different injector gas compositions.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 6.32
Times cited: 34
DOI: 10.1021/ac201699q
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“FIB, TEM and LA-ICPMS investigations on melt inclusions in Martian meteorites –, Analytical capabilities and geochemical insights”. Bleiner D, Macri M, Gasser P, Sautter V, Maras A, Talanta : the international journal of pure and applied analytical chemistry (2006). http://doi.org/10.1016/J.TALANTA.2005.08.022
Abstract: In order to obtain full information coverage on melt inclusions in Martian meteorites (subgroup nakhlites) complementary micro-analytical techniques were used, i.e. focused ion beam, transmission electron microscopy and laser ablation. Using focused ion beam several lamellae for transmission electron microscopy were prepared and secondary electron images of cross-sections could be acquired. Laser ablation-inductively coupled plasma mass spectrometry analyses were performed on selected inclusions to obtain mass-oriented bulk composition of inclusions at depth. The differences in composition between melt inclusions in olivine and augite crystals would suggest a xenocrystic origin for olivine. Furthermore, electron diffraction patterns clearly indicated that the SiO2-rich phase in inclusions from augite in meteorites from Northwest Africa site is re-crystallized, whereas it is still vitreous in the inclusions from Nakhla sampling site. Therefore, different post-entrapment evolutions were active for the two nakhlite meteorite sets, the Nakhla and the NWA817 set. Melt inclusions in Nakhla olivine presented alteration veins, which were presumably produced before their landing on Earth. If this is the case, this would indicate a alteration stage already on Mars with all the consequence in terms of climate history. Melt inclusions in Nakhla augite resulted unaffected by any alteration or modification following the entrapment, and therefore represent the best candidate to indicate the pristine magma composition. (c) 2005 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 4.162
Times cited: 9
DOI: 10.1016/J.TALANTA.2005.08.022
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