“Immersion calorimetry as a tool to evaluate the catalytic performance of titanosilicate materials in the epoxidation of cyclohexene”. Vernimmen J, Guidotti M, Silvestre-Albero J, Jardim EO, Mertens M, Lebedev OI, Van Tendeloo G, Psaro R, Rodríguez-Reinoso F, Meynen V, Cool P, Langmuir: the ACS journal of surfaces and colloids 27, 3618 (2011). http://doi.org/10.1021/la104808v
Abstract: Different types of titanosilicates are synthesized, structurally characterized, and subsequently catalytically tested in the liquid-phase epoxidation of cyclohexene. The performance of three types of combined zeolitic/mesoporous materials is compared with that of widely studied Ti-grafted-MCM-41 molecular sieve and the TS-1 microporous titanosilicate. The catalytic test results are correlated with the structural characteristics of the different catalysts. Moreover, for the first time, immersion calorimetry with the same substrate molecule as in the catalytic test reaction is applied as an extra means to interpret the catalytic results. A good correlation between catalytic performance and immersion calorimetry results is found. This work points out that the combination of catalytic testing and immersion calorimetry can lead to important insights into the influence of the materials structural characteristics on catalysis. Moreover, the potential of using immersion calorimetry as a screening tool for catalysts in epoxidation reactions is shown.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Impact Factor: 3.833
Times cited: 19
DOI: 10.1021/la104808v
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“New insights in the formation of combined zeolitic/mesoporous materials by using a one-pot templating synthesis”. Vernimmen J, Meynen V, Herregods SJF, Mertens M, Lebedev OI, Van Tendeloo G, Cool P, European journal of inorganic chemistry , 4234 (2011). http://doi.org/10.1002/ejic.201100268
Abstract: Zeolitic growth is often absent or occurs in separate phases when synthetic strategies based on the combination of zeolite templates and mesopore templating agents are applied. In this work, zeolitic growth and mesopore formation have been investigated at different temperatures by applying a one-pot templating approach, based on a TS-1 zeolite synthesis whereby part of the microtemplate (tetrapropylammonium hydroxide, TPAOH) is replaced by a mesotemplate (hexadecyltrimethylammonium bromide, CTMABr). Moreover, the synthesis duration and the molar ratio of the microtemplate/mesotemplate have also been studied. The different syntheses clearly show the inherent competitive mechanism between zeolitic growth and mesopore formation. These insights have led to the conclusion that by following a one-pot templating strategy with standard, nonexotic commercial templates, i.e. CTMABr and TPAOH, it is not possible to develop a true hierarchical mesoporous zeolite, meaning a mesoporous siliceous material with highly crystalline zeolitic walls. The resultant materials are instead combined zeolitic/mesoporous composite structures with, however, highly tuneable and controllable porosity characteristics.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Impact Factor: 2.444
Times cited: 7
DOI: 10.1002/ejic.201100268
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“Formation of a Ti-siliceous trimodal material with macroholes, mesopores and zeolitic features via a one-pot templating synthesis”. Vernimmen J, Meynen V, Mertens M, Lebedev OI, Van Tendeloo G, Cool P, Journal of porous materials 19, 153 (2012). http://doi.org/10.1007/s10934-011-9470-0
Abstract: Based on a facile one-pot templating synthesis, using a TS-1 zeolite recipe whereby part of the zeolite structure directing agent is replaced by a mesopore templating agent, a trimodal material is formed. The resulting meso-TSM material combines mesoporosity (Ti-MCM-41) with zeolitic features (TS-1) and a unique sheet-like morphology with uniform macroporous voids (macroholes). Moreover, the macrohole formation, mesoporosity and zeolitic properties of the meso-TSM material can be controlled in a straightforward way by adjusting the length of the hydrothermal treatment. This newly developed material may imply great potential for catalytic redox applications and diffusion limitated processes because of its highly tunable character in all three dimensions (micro-, meso- and macroporous scale).
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Impact Factor: 1.624
Times cited: 2
DOI: 10.1007/s10934-011-9470-0
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“Chemical, structural and electrical characterizations in the BIZNVOX family”. Vernochet C, Vannier R-N, Huvé, M, Pirovano C, Nowogrocki G, Mairesse G, Van Tendeloo G, Journal of materials chemistry 10, 2811 (2000). http://doi.org/10.1039/b006157n
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 13
DOI: 10.1039/b006157n
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“3D arrangement of epitaxial graphene conformally grown on porousified crystalline SiC”. Veronesi S, Pfusterschmied G, Fabbri F, Leitgeb M, Arif O, Esteban DA, Bals S, Schmid U, Heun S, Carbon 189, 210 (2022). http://doi.org/10.1016/j.carbon.2021.12.042
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 10.9
Times cited: 3
DOI: 10.1016/j.carbon.2021.12.042
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“Quantum mechanical solver for confined heterostructure tunnel field-effect transistors”. Verreck D, Van de Put M, Sorée B, Verhulst AS, Magnus W, Vandenberghe WG, Collaert N, Thean A, Groeseneken G, Journal of applied physics 115, 053706 (2014). http://doi.org/10.1063/1.4864128
Abstract: Heterostructure tunnel field-effect transistors (HTFET) are promising candidates for low-power applications in future technology nodes, as they are predicted to offer high on-currents, combined with a sub-60 mV/dec subthreshold swing. However, the effects of important quantum mechanical phenomena like size confinement at the heterojunction are not well understood, due to the theoretical and computational difficulties in modeling realistic heterostructures. We therefore present a ballistic quantum transport formalism, combining a novel envelope function approach for semiconductor heterostructures with the multiband quantum transmitting boundary method, which we extend to 2D potentials. We demonstrate an implementation of a 2-band version of the formalism and apply it to study confinement in realistic heterostructure diodes and p-n-i-n HTFETs. For the diodes, both transmission probabilities and current densities are found to decrease with stronger confinement. For the p-n-i-n HTFETs, the improved gate control is found to counteract the deterioration due to confinement. (C) 2014 AIP Publishing LLC.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.068
Times cited: 15
DOI: 10.1063/1.4864128
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“Improved source design for p-type tunnel field-effect transistors : towards truly complementary logic”. Verreck D, Verhulst AS, Sorée B, Collaert N, Mocuta A, Thean A, Groeseneken G, Applied physics letters 105, 243506 (2014). http://doi.org/10.1063/1.4904712
Abstract: Complementary logic based on tunnel field-effect transistors (TFETs) would drastically reduce power consumption thanks to the TFET's potential to obtain a sub-60 mV/dec subthreshold swing (SS). However, p-type TFETs typically do not meet the performance of n-TFETs for direct bandgap III-V configurations. The p-TFET SS stays well above 60 mV/dec, due to the low density of states in the conduction band. We therefore propose a source configuration in which a highly doped region is maintained only near the tunnel junction. In the remaining part of the source, the hot carriers in the exponential tail of the Fermi-Dirac distribution are blocked by reducing the doping degeneracy, either with a source section with a lower doping concentration or with a heterostructure. We apply this concept to n-p-i-p configurations consisting of In0.53Ga0.47As and an InP-InAs heterostructure. 15-band quantum mechanical simulations predict that the configurations with our source design can obtain sub-60 mV/dec SS, with an on-current comparable to the conventional source design. (C) 2014 AIP Publishing LLC.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 10
DOI: 10.1063/1.4904712
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“Full-zone spectral envelope function formalism for the optimization of line and point tunnel field-effect transistors”. Verreck D, Verhulst AS, Van de Put M, Sorée B, Magnus W, Mocuta A, Collaert N, Thean A, Groeseneken G, Journal of applied physics 118, 134502 (2015). http://doi.org/10.1063/1.4931890
Abstract: Efficient quantum mechanical simulation of tunnel field-effect transistors (TFETs) is indispensable to allow for an optimal configuration identification. We therefore present a full-zone 15-band quantum mechanical solver based on the envelope function formalism and employing a spectral method to reduce computational complexity and handle spurious solutions. We demonstrate the versatility of the solver by simulating a 40 nm wide In0.53Ga0.47As lineTFET and comparing it to p-n-i-n configurations with various pocket and body thicknesses. We find that the lineTFET performance is not degraded compared to semi-classical simulations. Furthermore, we show that a suitably optimized p-n-i-n TFET can obtain similar performance to the lineTFET. (C) 2015 AIP Publishing LLC.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.068
Times cited: 9
DOI: 10.1063/1.4931890
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“Uniform strain in heterostructure tunnel field-effect transistors”. Verreck D, Verhulst AS, Van de Put ML, Sorée B, Collaert N, Mocuta A, Thean A, Groeseneken G, IEEE electron device letters 37, 337 (2016). http://doi.org/10.1109/LED.2016.2519681
Abstract: Strain can strongly impact the performance of III-V tunnel field-effect transistors (TFETs). However, previous studies on homostructure TFETs have found an increase in ON-current to be accompanied with a degradation of subthreshold swing. We perform 30-band quantum mechanical simulations of staggered heterostructure p-n-i-n TFETs submitted to uniaxial and biaxial uniform stress and find the origin of the subthreshold degradation to be a reduction of the density of states in the strained case. We apply an alternative configuration including a lowly doped pocket in the source, which allows to take full benefit of the strain-induced increase in ON-current.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.048
Times cited: 17
DOI: 10.1109/LED.2016.2519681
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“Self-consistent procedure including envelope function normalization for full-zone Schrodinger-Poisson problems with transmitting boundary conditions”. Verreck D, Verhulst AS, Van de Put ML, Sorée B, Magnus W, Collaert N, Mocuta A, Groeseneken G, Journal of applied physics 124, 204501 (2018). http://doi.org/10.1063/1.5047087
Abstract: In the quantum mechanical simulation of exploratory semiconductor devices, continuum methods based on a k.p/envelope function model have the potential to significantly reduce the computational burden compared to prevalent atomistic methods. However, full-zone k.p/envelope function simulation approaches are scarce and existing implementations are not self-consistent with the calculation of the electrostatic potential due to the lack of a stable procedure and a proper normalization of the multi-band envelope functions. Here, we therefore present a self-consistent procedure based on a full-zone spectral k.p/envelope function band structure model. First, we develop a proper normalization for the multi-band envelope functions in the presence of transmitting boundary conditions. This enables the calculation of the free carrier densities. Next, we construct a procedure to obtain self-consistency of the carrier densities with the electrostatic potential. This procedure is stabilized with an adaptive scheme that relies on the solution of Poisson's equation in the Gummel form, combined with successive underrelaxation. Finally, we apply our procedure to homostructure In0.53Ga0.47As tunnel field-effect transistors (TFETs) and staggered heterostructure GaAs0.5Sb0.5/In0.53Ga0.47As TFETs and show the importance of self-consistency on the device predictions for scaled dimensions. Published by AIP Publishing.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.068
Times cited: 1
DOI: 10.1063/1.5047087
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“Field demonstration and evaluation of the passive flux meter on a CAH groundwater plume”. Verreydt G, Annable MD, Kaskassian S, van Keer I, Bronders J, Diels L, Vanderauwera P, Environmental Science and Pollution Research 20, 4621 (2013). http://doi.org/10.1007/S11356-012-1417-8
Abstract: This study comprises the first application of the Passive Flux Meter (PFM) for the measurement of chlorinated aliphatic hydrocarbon (CAH) mass fluxes and Darcy water fluxes in groundwater at a European field site. The PFM was originally developed and applied to measurements near source zones. The focus of the PFM is extended from near source to plume zones. For this purpose, 48 PFMs of 1.4 m length were constructed and installed in eight different monitoring wells in the source and plume zone of a CAH-contaminated field site located in France. The PFMs were retrieved, sampled, and analyzed after 3 to 11 weeks of exposure time, depending on the expected contaminant flux. PFM evaluation criteria include analytical, technical, and practical aspects as well as conditions and applicability. PFM flux data were compared with so-called traditional soil and groundwater concentration data obtained using active sampling methods. The PFMs deliver reasonable results for source as well as plume zones. The limiting factor in the PFM applicability is the exposure time together with the groundwater flux. Measured groundwater velocities at the field site range from 2 to 41 cm/day. Measured contaminant flux data raise up to 13 g/m(2)/day for perchloroethylene in the plume zone. Calculated PFM flux averaged concentration data and traditional concentration data were of similar magnitude for most wells. However, both datasets need to be compared with reservation because of the different sampling nature and time. Two important issues are the PFM tracer loss during installation/extraction and the deviation of the groundwater flow field when passing the monitoring well and PFM. The demonstration of the PFM at a CAH-contaminated field site in Europe confirmed the efficiency of the flux measurement technique for source as well as plume zones. The PFM can be applied without concerns in monitoring wells with European standards. The acquired flux data are of great value for the purpose of site characterization and mass discharge modeling, and can be used in combination with traditional soil and groundwater sampling methods.
Keywords: A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Biochemical Wastewater Valorization & Engineering (BioWaVE)
DOI: 10.1007/S11356-012-1417-8
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“Passive samplers for monitoring VOCs in groundwater and the prospects related to mass flux measurements”. Verreydt G, Bronders J, van Keer I, Diels L, Vanderauwera P, Ground water monitoring and remediation 30, 114 (2010). http://doi.org/10.1111/J.1745-6592.2010.01281.X
Abstract: Measurement and interpretation of mass fluxes in favor of concentrations is gaining more and more interest, especially within the framework of the characterization and management of large-scale volatile organic carbon (VOC) groundwater contamination (source zones and plumes). Traditional methods of estimating contaminant fluxes and discharges involve individual measurements/calculations of the Darcy water flux and the contaminant concentrations. However, taken into account the spatially and temporally varying hydrologic conditions in complex, heterogeneous aquifers, higher uncertainty arises from such indirect estimation of contaminant fluxes. Therefore, the potential use of passive sampling devices for the direct measurement of groundwater-related VOC mass fluxes is examined. A review of current passive samplers for the measurement of organic contaminants in water yielded the selection of 18 samplers that were screened for a number of criteria. These criteria are related to the possible application of the sampler for the measurement of VOC mass fluxes in groundwater. This screening study indicates that direct measurement of VOC mass fluxes in groundwater is possible with very few passive samplers. Currently, the passive flux meter (PFM) is the only passive sampler which has proven to effectively measure mass fluxes in near source groundwater. A passive sampler for mass flux measurement in plume zones with regard to long-term monitoring (several months to a year) still needs to be developed or optimized. A passive sampler for long-term monitoring of contaminant mass fluxes in groundwater would be of considerable value in the development of risk-based assessment and management of soil and groundwater pollutions.
Keywords: A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1111/J.1745-6592.2010.01281.X
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“In situ study of ballast tank corrosion on ships: part 1”. Verstraelen H, de Baere K, Schillemans W, Lemmens L, Dewil R, Lenaerts S, Potters G, Materials performance 48, 48 (2009)
Keywords: A1 Journal article; Engineering sciences. Technology; Theory of quantum systems and complex systems; Sustainable Energy, Air and Water Technology (DuEL)
Impact Factor: 0.149
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“In situ study of ballast tank corrosion on ships: part 2”. Verstraelen H, de Baere K, Schillemans W, Lemmens L, Dewil R, Lenaerts S, Potters G, Materials performance 48, 54 (2009)
Abstract: A study was undertaken to determine causes and effects of corrosion processes in ballast tanks. Part 1 of this article (October 2009 MP) described the data collection. Part 2 describes the development of a corrosion index (CI) derived from the general International Association of Classification Societies corrosion assessment methods. The CI can be used in situ to assess ballast tank corrosion. An average timeline for-corrosion of tanks is presented.
Keywords: A1 Journal article; Engineering sciences. Technology; Theory of quantum systems and complex systems; Sustainable Energy, Air and Water Technology (DuEL)
Impact Factor: 0.149
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“Used water and nutrients : recovery perspectives in a 'panta rhei' context”. Verstraete W, Clauwaert P, Vlaeminck SE, Bioresource technology 215, 199 (2016). http://doi.org/10.1016/J.BIORTECH.2016.04.094
Abstract: There is an urgent need to secure global supplies in safe water and proteinaceous food in an eco-sustainable manner, as manifested from tensions in the nexus Nutrients-Energy-Water-Environment-Land. This paper is concept based and provides solutions based on resource recovery from municipal and industrial wastewater and from manure. A set of decisive factors is reviewed facilitating an attractive business case. Our key message is that a robust barrier must clear the recovered product from its original status. Besides refined inorganic fertilizers, a central role for five types of microbial protein is proposed. A resource cycling solution for the extremely confined environment of space habitation should serve as an incentive to assimilate a new user mindset. To achieve the ambitious goal of sustainable food security, the solutions suggested here need a broad implementation, hand in hand with minimizing losses along the entire fertilizer-feed-food-fork chain. (C) 2016 Elsevier Ltd. All rights reserved.
Keywords: A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1016/J.BIORTECH.2016.04.094
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“Phototoxicity and cell passage affect intracellular reactive oxygen species levels and sensitivity towards non-thermal plasma treatment in fluorescently-labeled cancer cells”. Verswyvel H, Deben C, Wouters A, Lardon F, Bogaerts A, Smits E, Lin A, Journal of physics: D: applied physics 56, 294001 (2023). http://doi.org/10.1088/1361-6463/accc3d
Abstract: Live-cell imaging with fluorescence microscopy is a powerful tool, especially in cancer research, widely-used for capturing dynamic cellular processes over time. However, light-induced toxicity (phototoxicity) can be incurred from this method, via disruption of intracellular redox balance and an overload of reactive oxygen species (ROS). This can introduce confounding effects in an experiment, especially in the context of evaluating and screening novel therapies. Here, we aimed to unravel whether phototoxicity can impact cellular homeostasis and response to non-thermal plasma (NTP), a therapeutic strategy which specifically targets the intracellular redox balance. We demonstrate that cells incorporated with a fluorescent reporter for live-cell imaging have increased sensitivity to NTP, when exposed to ambient light or fluorescence excitation, likely through altered proliferation rates and baseline intracellular ROS levels. These changes became even more pronounced the longer the cells stayed in culture. Therefore, our results have important implications for research implementing this analysis technique and are particularly important for designing experiments and evaluating redox-based therapies like NTP.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Center for Oncological Research (CORE)
Impact Factor: 3.4
DOI: 10.1088/1361-6463/accc3d
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“Restricted energy transfer in laser desorption of high molecular weight biomolecules”. Vertes A, Gijbels R, Scanning microscopy 5, 317 (1991)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Times cited: 11
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“Hydrodynamic model of matrix-assisted laser desorption mass spectrometry”. Vertes A, Irinyi G, Gijbels R, Analytical chemistry 65, 2389 (1993). http://doi.org/10.1021/ac00065a036
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 5.636
Times cited: 100
DOI: 10.1021/ac00065a036
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“How important is reactor design for CO2 conversion in warm plasmas?”.Vertongen R, Bogaerts A, Journal of CO2 Utilization 72, 102510 (2023). http://doi.org/10.1016/j.jcou.2023.102510
Abstract: In this work, we evaluated several new electrode configurations for CO2 conversion in a gliding arc plasmatron
(GAP) reactor. Although the reactor design influences the performance, the best results give only slightly higher
CO2 conversion than the basic GAP reactor design, which indicates that this reactor may have reached its performance
limits. Moreover, we compared our results to those of four completely different plasma reactors, also
operating at atmospheric pressure and with contact between the plasma and the electrodes. Surprisingly, the
performance of all these warm plasmas is very similar (CO2 conversion around 10 % for an energy efficiency
around 30 %). In view of these apparent performance limits regarding the reactor design, we believe further
improvements should focus on other aspects, such as the post-plasma-region where the implementation of
nozzles or a carbon bed are promising. We summarize the performance of our GAP reactor by comparing the
energy efficiency and CO2 conversion for all different plasma reactors reported in literature. We can conclude
that the GAP is not the best plasma reactor, but its operation at atmospheric pressure makes it appealing for
industrial application. We believe that future efforts should focus on process design, techno-economic assessments
and large-scale demonstrations: these will be crucial to assess the real industrial potential of this warm
plasma technology
Keywords: A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Impact Factor: 7.7
DOI: 10.1016/j.jcou.2023.102510
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“Enhancing CO2 conversion with plasma reactors in series and O2 removal”. Vertongen R, Trenchev G, Van Loenhout R, Bogaerts A, Journal Of Co2 Utilization 66, 102252 (2022). http://doi.org/10.1016/j.jcou.2022.102252
Abstract: In this work, we take a crucial step towards the industrial readiness of plasma-based CO2 conversion. We present a stepwise method to study plasma reactors in series as a first approach to a recycle flow. By means of this procedure, the CO2 conversion is enhanced by a factor of 3, demonstrating that a single-pass plasma treatment performs far below the optimal capacity of the reactor. Furthermore, we explore the effect of O2 in the mixture with our flexible procedure. Addition of O2 in the mixture has a clear detrimental effect on the conversion, in agreement with other experiments in atmospheric pressure plasmas. O2 removal is however highly beneficial, demonstrating a conversion per pass that is 1.6 times higher than the standard procedure. Indeed, extracting one of the products prevents recombination reactions. Based on these insights, we discuss opportunities for further improvements, especially in the field of specialised separation techniques.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 7.7
DOI: 10.1016/j.jcou.2022.102252
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“Chronic interstitial nephritis in agricultural communities : a toxin-induced proximal tubular nephropathy”. Vervaet BA, Nast CC, Jayasumana C, Schreurs G, Roels F, Herath C, Kojc N, Samaee V, Rodrigo S, Gowrishankar R, European Medical Journal : Nephrology 8, 40 (2020)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Pathophysiology
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“Chronic interstitial nephritis in agricultural communities is a toxin induced proximal tubular nephropathy”. Vervaet BA, Nast CC, Jayasumana C, Schreurs G, Roels F, Herath C, Kojc N, Samaee V, Rodrigo S, Gowrishankar S, Mousson C, Dassanayake R, Orantes CM, Vuiblet V, Rigothier C, d' Haese PC, de Broe ME, Kidney international 97, 350 (2019). http://doi.org/10.1016/J.KINT.2019.11.009
Abstract: Almost 30 years after the detection of chronic interstitial nephritis in agricultural communities (CINAC) its etiology remains unknown. To help define this we examined 34 renal biopsies from Sri Lanka, El Salvador, India and France of patients with chronic kidney disease 2-3 and diagnosed with CINAC by light and electron microscopy. In addition to known histopathology, we identified a unique constellation of proximal tubular cell findings including large dysmorphic lysosomes with a light-medium electron-dense matrix containing dispersed dark electron-dense non-membrane bound “aggregates”. These aggregates associated with varying degrees of cellular/tubular atrophy, apparent cell fragment shedding and no-weak proximal tubular cell proliferative capacity. Identical lysosomal lesions, identifiable by electron microscopy, were observed in 9% of renal transplant implantation biopsies, but were more prevalent in six month (50%) and 12 month (67%) protocol biopsies and in indication biopsies (76%) of calcineurin inhibitor treated transplant patients. The phenotype was also found associated with nephrotoxic drugs (lomustine, clomiphene, lithium, cocaine) and in some patients with light chain tubulopathy, all conditions that can be directly or indirectly linked to calcineurin pathway inhibition or modulation. One hundred biopsies of normal kidneys, drug/toxin induced nephropathies, and overt proteinuric patients of different etiologies to some extent could demonstrate the light microscopic proximal tubular cell changes, but rarely the electron microscopic lysosomal features. Rats treated with the calcineurin inhibitor cyclosporine for four weeks developed similar proximal tubular cell lysosomal alterations, which were absent in a dehydration group. Overall, the finding of an identical proximal tubular cell (lysosomal) lesion in CINAC and calcineurin inhibitor nephrotoxicity in different geographic regions suggests a common paradigm where CINAC patients undergo a tubulotoxic mechanism similar to calcineurin inhibitor nephrotoxicity.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory Experimental Medicine and Pediatrics (LEMP); Pathophysiology
Impact Factor: 8.395
DOI: 10.1016/J.KINT.2019.11.009
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“Plasma-Based N2Fixation into NOx: Insights from Modeling toward Optimum Yields and Energy Costs in a Gliding Arc Plasmatron”. Vervloessem E, Aghaei M, Jardali F, Hafezkhiabani N, Bogaerts A, Acs Sustainable Chemistry &, Engineering 8, 9711 (2020). http://doi.org/10.1021/acssuschemeng.0c01815
Abstract: Plasma technology provides a sustainable, fossil-free method for N2 fixation, i.e., the conversion of inert atmospheric N2 into valuable substances, such as NOx or ammonia. In this work, we present a novel gliding arc plasmatron at atmospheric pressure for NOx production at different N2/O2 gas feed ratios, offering a promising NOx yield of 1.5% with an energy cost of 3.6 MJ/mol NOx produced. To explain the underlying mechanisms, we present a chemical kinetics model, validated by experiments, which provides insight into the NOx formation pathways and into the ambivalent role of the vibrational kinetics. This allows us to pinpoint the factors limiting the yield and energy cost, which can help to further improve the process.
Keywords: A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 8.4
DOI: 10.1021/acssuschemeng.0c01815
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“Sustainable NOxproduction from air in pulsed plasma: elucidating the chemistry behind the low energy consumption”. Vervloessem E, Gorbanev Y, Nikiforov A, De Geyter N, Bogaerts A, Green Chemistry 24, 916 (2022). http://doi.org/10.1039/D1GC02762J
Abstract: N-Based fertilisers are paramount to support our still-growing world population. Current industrial N<sub>2</sub>fixation is heavily fossil fuel-dependent, therefore, a lot of work is put into the development of fossil-free pathways. Plasma technology offers a fossil-free and flexible method for N<sub>2</sub>fixation that is compatible with renewable energy sources. We present here a pulsed plasma jet for direct NO<sub><italic>x</italic></sub>production from air. The pulsed power allows for a record-low energy consumption (EC) of 0.42 MJ (mol N)<sup>−1</sup>. This is the lowest reported EC in plasma-based N<sub>2</sub>fixation at atmospheric pressure thus far. We compare our experimental data with plasma chemistry modelling, and obtain very good agreement. Hence, we can use our model to explain the underlying mechanisms responsible for this low EC. The pulsed power and the corresponding pulsed gas temperature are the reason for the very low EC: they provide a strong vibrational–translational non-equilibrium and promote the non-thermal Zeldovich mechanism. This insight is important for the development of the next generation of plasma sources for energy-efficient NO<sub><italic>x</italic></sub>production.
Keywords: A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 9.8
DOI: 10.1039/D1GC02762J
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“NH3and HNOxFormation and Loss in Nitrogen Fixation from Air with Water Vapor by Nonequilibrium Plasma”. Vervloessem E, Gromov M, De Geyter N, Bogaerts A, Gorbanev Y, Nikiforov A, ACS Sustainable Chemistry and Engineering 11, 4289 (2023). http://doi.org/10.1021/acssuschemeng.3c00208
Abstract: The current global energy crisis indicated that increasing our
insight into nonfossil fuel nitrogen fixation pathways for synthetic fertilizer
production is more crucial than ever. Nonequilibrium plasma is a good candidate
because it can use N2 or air as a N source and water directly as a H source, instead
of H2 or fossil fuel (CH4). In this work, we investigate NH3 gas phase formation
pathways from humid N2 and especially humid air up to 2.4 mol % H2O (100%
relative humidity at 20 °C) by optical emission spectroscopy and Fouriertransform
infrared spectroscopy. We demonstrate that the nitrogen fixation
capacity is increased when water vapor is added, as this enables HNO2 and NH3
production in both N2 and air. However, we identified a significant loss
mechanism for NH3 and HNO2 that occurs in systems where these species are
synthesized simultaneously; i.e., downstream from the plasma, HNO2 reacts with NH3 to form NH4NO2, which rapidly decomposes
into N2 and H2O. We also discuss approaches to prevent this loss mechanism, as it reduces the effective nitrogen fixation when not
properly addressed and therefore should be considered in future works aimed at optimizing plasma-based N2 fixation. In-line removal
of HNO2 or direct solvation in liquid are two proposed strategies to suppress this loss mechanism. Indeed, using liquid H2O is
beneficial for accumulation of the N2 fixation products. Finally, in humid air, we also produce NH4NO3, from the reaction of HNO3
with NH3, which is of direct interest for fertilizer application.
Keywords: A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 8.4
DOI: 10.1021/acssuschemeng.3c00208
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“Stabilities of bimetallic nanoparticles for chirality-selective carbon nanotube growth and the effect of carbon interstitials”. Vets C, Neyts EC, The journal of physical chemistry: C : nanomaterials and interfaces 121, 15430 (2017). http://doi.org/10.1021/ACS.JPCC.7B02880
Abstract: Bimetallic nanoparticles play a crucial role in various applications. A better understanding of their properties would facilitate these applications and possibly even enable chirality-specific growth of carbon nanotubes (CNTs). We here examine the stabilities of NiFe, NiGa, and FeGa nanoparticles and the effect of carbon dissolved in NiFe nanoparticles through density functional theory (DFT) calculations and Born Oppenheimer molecular dynamics (BOMD) simulations. We establish that nanoparticles with more Fe in the core and more Ga on the surface are more stable and compare these results with well-known properties such as surface energy and atom size. Furthermore, we find that the nanoparticles become more stable with increasing carbon content, both at 0 K and at 700 K. These results provide a basis for further research into the chirality-specific growth of CNT's.
Keywords: A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 4.536
Times cited: 2
DOI: 10.1021/ACS.JPCC.7B02880
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“Sailing through end-of-life challenges : a comprehensive review for offshore wind”. Vetters J, Thomassen G, Van Passel S, Renewable and sustainable energy reviews 199, 114486 (2024). http://doi.org/10.1016/J.RSER.2024.114486
Abstract: Over the past thirty years, European offshore wind farm development surged, yet end-of-life and decommissioning considerations were overshadowed by initial climate and energy security objectives during design and construction. As the first major projects near their final decade, numerous unanswered questions persist. Through a comprehensive literature review, this study identifies, maps, and evaluates challenges across technical, economic, environmental, social, and policy dimensions spanning five end-of-life phases: planning, dismantling, transport and logistics, waste management, and site recovery. Examining 42 publications reveals 46 distinct challenges affecting stakeholders such as the end-of-life supply chain, policy makers, and society. While 33% of the challenges manifested in the technical dimension, 48% of the challenges covered the planning phase. Notably, the economic challenge of vessel cost and availability was raised most often. Less-explored challenges underscore the importance of consideration before the end-of-life phase intensifies. The study illustrates the complex interconnection of numerous end-of-life challenges across phases, dimensions, and disciplines, emphasizing the imperative of addressing bottlenecks in a comprehensive and integrated manner. The results of this study help steering future research, while also improving awareness of challenges for stakeholders, emphasizing the need for collaborative efforts between governmental bodies and industry stakeholders to address imminent challenges through transparent guidelines, data exchange, and circular design principles. The novelty of this study lies in its holistic, multidisciplinary approach, systematic framework for identifying challenges, and critical perspective unveiling interconnectedness.
Keywords: A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM)
Impact Factor: 15.9
DOI: 10.1016/J.RSER.2024.114486
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“Oxidation processes at the metal/oxide interface in CoFe2/CoFe2O4 bilayers deposited by pulsed laser deposition”. Viart N, Sayed Hassan R, Ulhaq-Bouillet C, Meny C, Panissod P, Loison JL, Versini G, Huber F, Pourroy G, Verbeeck J, Van Tendeloo G, Acta materialia 54, 191 (2006). http://doi.org/10.1016/j.actamat.2005.08.041
Abstract: CoFe2/CoFe2O4 bilayers were made by pulsed laser ablation of a CoFe2 target on Si(I 0 0) substrates. The metallic layer was deposited first, in vacuum. The oxide was then deposited in an oxidizing O-2:N-2 (20:80) atmosphere. Two different procedures were used for the introduction of the oxidizing atmosphere in the deposition chamber: the laser ablation of the target was either stopped (discontinuous deposition process) or maintained (continuous deposition process) during the 20 min necessary for the establishment of the desired O-2:N-2 pressure. In both cases, the different electronegativities of Fe and Co cause an important modification of the Fe/Co ratio at the metal/oxide interface, with a depletion of Fe in the metal region and of Co in the oxide region. In the continuous procedure, the combination of the kinetic energy given by the ablation process to the Fe and Co adatoms with the one they get from their different affinity towards oxidation allows the formation of a low roughness metal/oxide interface with a high (111) preferred orientation of the CoFe2O4 layer, an induced re-crystallisation of the metal layer underneath and an unusual antiferromagnetic metal/oxide magnetic coupling. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 5.301
Times cited: 5
DOI: 10.1016/j.actamat.2005.08.041
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“Heterometal nanoparticles from Ru-based molecular clusters covalently anchored onto functionalized carbon nanotubes and nanofibers”. Vidick D, Ke X, Devillers M, Poleunis C, Delcorte A, Moggi P, Van Tendeloo G, Hermans S, Beilstein journal of nanotechnology 6, 1287 (2015). http://doi.org/10.3762/bjnano.6.133
Abstract: Heterometal clusters containing Ru and Au, Co and/or Pt are anchored onto carbon nanotubes and nanofibers functionalized with chelating phosphine groups. The cluster anchoring yield is related to the amount of phosphine groups available on the nanocarbon surface. The ligands of the anchored molecular species are then removed by gentle thermal treatment in order to form nanoparticles. In the case of Au-containing clusters, removal of gold atoms from the clusters and agglomeration leads to a bimodal distribution of nanoparticles at the nanocarbon surface. In the case of Ru-Pt species, anchoring occurs without reorganization through a ligand exchange mechanism. After thermal treatment, ultrasmall (1-3 nm) bimetal Ru-Pt nanoparticles are formed on the surface of the nanocarbons. Characterization by high resolution transmission electron microscopy (HRTEM) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) confirms their bimetal nature on the nanoscale. The obtained bimetal nanoparticles supported on nanocarbon were tested as catalysts in ammonia synthesis and are shown to be active at low temperature and atmospheric pressure with very low Ru loading.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.127
Times cited: 7
DOI: 10.3762/bjnano.6.133
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“Absence of a pressure gap and atomistic mechanism of the oxidation of pure Co nanoparticles”. Vijayakumar J, Savchenko TM, Bracher DM, Lumbeeck G, Béché, A, Verbeeck J, Vajda Š, Nolting F, Vaz Caf, Kleibert A, Nature communications 14, 174 (2023). http://doi.org/10.1038/s41467-023-35846-0
Abstract: Understanding chemical reactivity and magnetism of 3<italic>d</italic>transition metal nanoparticles is of fundamental interest for applications in fields ranging from spintronics to catalysis. Here, we present an atomistic picture of the early stage of the oxidation mechanism and its impact on the magnetism of Co nanoparticles. Our experiments reveal a two-step process characterized by (i) the initial formation of small CoO crystallites across the nanoparticle surface, until their coalescence leads to structural completion of the oxide shell passivating the metallic core; (ii) progressive conversion of the CoO shell to Co<sub>3</sub>O<sub>4</sub>and void formation due to the nanoscale Kirkendall effect. The Co nanoparticles remain highly reactive toward oxygen during phase (i), demonstrating the absence of a pressure gap whereby a low reactivity at low pressures is postulated. Our results provide an important benchmark for the development of theoretical models for the chemical reactivity in catalysis and magnetism during metal oxidation at the nanoscale.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 16.6
Times cited: 1
DOI: 10.1038/s41467-023-35846-0
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