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Author Alves, L.L.; Bogaerts, A.; Guerra, V.; Turner, M.M.
Title Foundations of modelling of nonequilibrium low-temperature plasmas Type A1 Journal article
Year 2018 Publication (up) Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 27 Issue 2 Pages 023002
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract This work explains the need for plasma models, introduces arguments for choosing the type of model that better fits the purpose of each study, and presents the basics of the most common nonequilibrium low-temperature plasma models and the information available from each one, along with an extensive list of references for complementary in-depth reading. The paper presents the following models, organised according to the level of multi-dimensional description of the plasma: kinetic models, based on either a statistical particle-in-cell/Monte-Carlo approach or the solution to the Boltzmann equation (in the latter case, special focus is given to the description of the electron kinetics); multi-fluid models, based on the solution to the hydrodynamic equations; global (spatially-average) models, based on the solution to the particle and energy rate-balance equations for the main plasma species, usually including a very complete reaction chemistry; mesoscopic models for plasma–surface interaction, adopting either a deterministic approach or a stochastic dynamical Monte-Carlo approach. For each plasma model, the paper puts forward the physics context, introduces the fundamental equations, presents advantages and limitations, also from a numerical perspective, and illustrates its application with some examples. Whenever pertinent, the interconnection between models is also discussed, in view of multi-scale hybrid approaches.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000425688600001 Publication Date 2018-02-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 17 Open Access OpenAccess
Notes The authors would like to thank A Tejero-Del-Caz and A Berthelot for their technical contributions in writing the manuscript. This work was partially funded by Portuguese FCT —Fundação para a Ciência e a Tecnologia, under projects UID/ FIS/50010/2013, PTDC/FISPLA/1243/2014 (KIT-PLAS- MEBA) and PTDC/FIS-PLA/1420/2014 (PREMiERE). Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:149391 Serial 4810
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Author Bal, K.M.; Huygh, S.; Bogaerts, A.; Neyts, E.C.
Title Effect of plasma-induced surface charging on catalytic processes: application to CO2activation Type A1 Journal article
Year 2018 Publication (up) Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 27 Issue 2 Pages 024001
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Understanding the nature and effect of the multitude of plasma–surface interactions in plasma catalysis is a crucial requirement for further process development and improvement. A particularly intriguing and rather unique property of a plasma-catalytic setup is the ability of the plasma to modify the electronic structure, and hence chemical properties, of the catalyst through charging, i.e. the absorption of excess electrons. In this work, we develop a quantum chemical model based on density functional theory to study excess negative surface charges in a heterogeneous catalyst exposed to a plasma. This method is specifically applied to investigate plasma-catalytic CO2 activation on supported M/Al2O3 (M=Ti, Ni, Cu) single atom catalysts. We find that (1) the presence of a negative surface charge dramatically improves the reductive power of the catalyst, strongly promoting the splitting of CO2 to CO and oxygen, and (2) the relative activity of the investigated transition metals is also changed upon charging, suggesting that controlled surface charging is a powerful additional parameter to tune catalyst activity and selectivity. These results strongly point to plasma-induced surface charging of the catalyst as an important factor contributing to the plasma-catalyst synergistic effects frequently reported for plasma catalysis.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000424520100001 Publication Date 2018-02-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 19 Open Access OpenAccess
Notes KMB is funded as PhD fellow (aspirant) of the FWO-Flanders (Research Foundation—Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government— department EWI. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:149285 Serial 4813
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Author Zhang, Q.-Z.; Bogaerts, A.
Title Propagation of a plasma streamer in catalyst pores Type A1 Journal article
Year 2018 Publication (up) Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 27 Issue 3 Pages 035009
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Although plasma catalysis is gaining increasing interest for various environmental applications, the underlying mechanisms are still far from understood. For instance, it is not yet clear whether and how plasma streamers can propagate in catalyst pores, and what is the minimum pore size to make this happen. As this is crucial information to ensure good plasma-catalyst interaction, we study here the mechanism of plasma streamer propagation in a catalyst pore, by means of a twodimensional particle-in-cell/Monte Carlo collision model, for various pore diameters in the nm range to μm-range. The so-called Debye length is an important criterion for plasma penetration into catalyst pores, i.e. a plasma streamer can penetrate into pores when their diameter is larger than the Debye length. The Debye length is typically in the order of a few 100 nm up to 1 μm at the conditions under study, depending on electron density and temperature in the plasma streamer. For pores in the range of ∼50 nm, plasma can thus only penetrate to some extent and at

very short times, i.e. at the beginning of a micro-discharge, before the actual plasma streamer reaches the catalyst surface and a sheath is formed in front of the surface. We can make plasma streamers penetrate into smaller pores (down to ca. 500 nm at the conditions under study) by increasing the applied voltage, which yields a higher plasma density, and thus reduces the Debye length. Our simulations also reveal that the plasma streamers induce surface charging of the catalyst pore sidewalls, causing discharge enhancement inside the pore, depending on pore diameter and depth.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000427976800001 Publication Date 2018-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 16 Open Access OpenAccess
Notes We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the Fund for Scientific Research Flanders (FWO) (Excellence of Science Program; EOS ID 30505023). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:150877 Serial 4954
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Author Zhang, Q.-Z.; Wang, W.-Z.; Bogaerts, A.
Title Importance of surface charging during plasma streamer propagation in catalyst pores Type A1 Journal article
Year 2018 Publication (up) Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 27 Issue 6 Pages 065009
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma catalysis is gaining increasing interest, but the underlying mechanisms are far from understood. Different catalyst materials will have different chemical effects, but in addition, they might also have different dielectric constants, which will affect surface charging, and thus the plasma behavior. In this work, we demonstrate that surface charging plays an important role in the streamer propagation and discharge enhancement inside catalyst pores, and in the plasma distribution along the dielectric surface, and this role greatly depends on the dielectric constant of the material. For εr50, surface charging causes the plasma to spread along the dielectric surface and inside the pores, leading to deeper plasma streamer penetration, while for εr>50 or for metallic coatings, the discharge is more localized, due to very weak surface charging. In addition, at εr=50, the significant surface charge density near the pore entrance causes a large potential drop at the sharp pore edges, which induces a strong electric field and results in most pronounced plasma enhancement near the pore entrance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000436845700002 Publication Date 2018-06-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 13 Open Access OpenAccess
Notes We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the TOP-BOF project of the University of Antwerp. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:152243 Serial 4995
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Author Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A.
Title Enhancement of plasma generation in catalyst pores with different shapes Type A1 Journal article
Year 2018 Publication (up) Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 27 Issue 5 Pages 055008
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma generation inside catalyst pores is of utmost importance for plasma catalysis, as the existence of plasma species inside the pores affects the active surface area of the catalyst available to the plasma species for catalytic reactions. In this paper, the electric field enhancement, and thus the plasma production inside catalyst pores with different pore shapes is studied with a two-dimensional fluid model. The results indicate that the electric field will be significantly enhanced near tip-like structures. In a conical pore with small opening, the strongest electric field appears at the opening and bottom corners of the pore, giving rise to a prominent ionization rate throughout the pore. For a cylindrical pore, the electric field is only enhanced at the bottom corners of the pore, with lower absolute value, and thus the ionization rate inside the pore is only slightly enhanced. Finally, in a conical pore with large opening, the electric field is characterized by a maximum at the bottom of the pore, yielding a similar behavior for the ionization rate. These results demonstrate that the shape of the pore has a significantly influence on the electric field enhancement, and thus modifies the plasma properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000432351700002 Publication Date 2018-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 11 Open Access OpenAccess
Notes This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant No. G.0217.14N) and the Fundamental Research Funds for the Central Universities (Grant No. DUT17LK52). Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:151546 Serial 4998
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Author Wang, L.; Wen, D.-Q.; Zhang, Q.-Z.; Song, Y.-H.; Zhang, Y.-R.; Wang, Y.-N.
Title Disruption of self-organized striated structure induced by secondary electron emission in capacitive oxygen discharges Type A1 Journal article
Year 2019 Publication (up) Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 28 Issue 5 Pages 055007
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Self-organized striated structure has been observed experimentally and numerically in CF4 plasmas in radio-frequency capacitively coupled plasmas recently (Liu et al 2016 Phys. Rev. Lett. 116 255002). In this work, the striated structure is investigated in a capacitively coupled oxygen discharge with the introduction of the effect from the secondary electron emission, based on a particle-in-cell/Monte Carlo collision model. As we know, the transport of positive and negative ions plays a key role in the formation of striations in electronegative gases, for which, the electronegativity needs to be large enough. As the secondary electron emission increases, electrons in the sheaths gradually contribute more ionization to the discharge. Meanwhile, the increase of the electron density, especially in the plasma bulk, leads to an increased electrical conductivity and a reduced bulk electric field, which would shield the ions' mobility. These changes result in enlarged striation gaps. And then, with more emitted electrons, obvious disruption of the striations is observed accompanied with a transition of electron heating mode. Due to the weakened field, the impact ionization in the plasma bulk is attenuated, compared with the enhanced ionization caused by secondary electrons. This would lead to the electron heating mode transition from striated (STR) mode to gamma-mode. Besides, our investigation further reveals that gamma-mode is more likely to dominate the discharge under high gas pressures or driving voltages.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000467827800001 Publication Date 2019-04-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 2 Open Access Not_Open_Access: Available from 13.05.2020
Notes Approved Most recent IF: 3.302
Call Number UA @ admin @ c:irua:160365 Serial 5270
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Author Bissonnette-Dulude, J.; Heirman, P.; Coulombe, S.; Bogaerts, A.; Gervais, T.; Reuter, S.
Title Coupling the COST reference plasma jet to a microfluidic device: a computational study Type A1 Journal Article
Year 2024 Publication (up) Plasma sources science and technology Abbreviated Journal Plasma Sources Sci. Technol.
Volume 33 Issue 1 Pages 015001
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The use of microfluidic devices in the field of plasma-liquid interaction can unlock unique possibilities to investigate the effects of plasma-generated reactive species for environmental and biomedical applications. So far, very little simulation work has been performed on microfluidic devices in contact with a plasma source. We report on the modelling and computational simulation of physical and chemical processes taking place in a novel plasma-microfluidic platform. The main production and transport pathways of reactive species both in plasma and liquid are modelled by a novel modelling approach that combines 0D chemical kinetics and 2D transport mechanisms. This combined approach, applicable to systems where the transport of chemical species occurs in unidirectional flows at high Péclet numbers, decreases calculation times considerably compared to regular 2D simulations. It takes advantage of the low computational time of the 0D reaction models while providing spatial information through multiple plug-flow simulations to yield a quasi-2D model. The gas and liquid flow profiles are simulated entirely in 2D, together with the chemical reactions and transport of key chemical species. The model correctly predicts increased transport of hydrogen peroxide into the liquid when the microfluidic opening is placed inside the plasma effluent region, as opposed to inside the plasma region itself. Furthermore, the modelled hydrogen peroxide production and transport in the microfluidic liquid differs by less than 50% compared with experimental results. To explain this discrepancy, the limits of the 0D–2D combined approach are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001136607100001 Publication Date 2024-01-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.8 Times cited Open Access Not_Open_Access
Notes Natural Sciences and Engineering Research Council of Canada, RGPIN-06820 ; FWO, 1100421N ; McGill University, the TransMedTech Institute; Approved Most recent IF: 3.8; 2024 IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:202783 Serial 8990
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Author Biondo, O.; Hughes, A.; van der Steeg, A.; Maerivoet, S.; Loenders, B.; van Rooij, G.; Bogaerts, A.
Title Power concentration determined by thermodynamic properties in complex gas mixtures : the case of plasma-based dry reforming of methane Type A1 Journal article
Year 2023 Publication (up) Plasma sources science and technology Abbreviated Journal
Volume 32 Issue 4 Pages 045001-45020
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We investigate discharge contraction in a microwave plasma at sub-atmospheric pressure, operating in CO2 and CO2/CH4 mixtures. The rise of the electron number density with plasma contraction intensifies the gas heating in the core of the plasma. This, in turn, initiates fast core-periphery transport and defines the rate of thermal chemistry over plasma chemistry. In this context, power concentration describes the overall mechanism including plasma contraction and chemical kinetics. In a complex chemistry such as dry reforming of methane, transport of reactive species is essential to define the performance of the reactor and achieve the desired outputs. Thus, we couple experimental observations and thermodynamic calculations for model validation and understanding of reactor performance. Adding CH4 alters the thermodynamic properties of the mixture, especially the reactive component of the heat conductivity. The increase in reactive heat conductivity increases the pressure at which plasma contraction occurs, because higher rates of gas heating are required to reach the same temperature. In addition, we suggest that the predominance of heat conduction over convection is a key condition to observe the effect of heat conductivity on gas temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000963579500001 Publication Date 2023-03-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.8 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 3.8; 2023 IF: 3.302
Call Number UA @ admin @ c:irua:196044 Serial 8397
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Author Vanraes, P.; Parayil Venugopalan, S.; Besemer, M.; Bogaerts, A.
Title Assessing neutral transport mechanisms in aspect ratio dependent etching by means of experiments and multiscale plasma modeling Type A1 Journal Article
Year 2023 Publication (up) Plasma Sources Science and Technology Abbreviated Journal Plasma Sources Sci. Technol.
Volume 32 Issue 6 Pages 064004
Keywords A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract Since the onset of pattern transfer technologies for chip manufacturing, various strategies have been developed to circumvent or overcome aspect ratio dependent etching (ARDE). These methods have, however, their own limitations in terms of etch non-idealities, throughput or costs. Moreover, they have mainly been optimized for individual in-device features and die-scale patterns, while occasionally ending up with poor patterning of metrology marks, affecting the alignment and overlay in lithography. Obtaining a better understanding of the underlying mechanisms of ARDE and how to mitigate them therefore remains a relevant challenge to date, for both marks and advanced nodes. In this work, we accordingly assessed the neutral transport mechanisms in ARDE by means of experiments and multiscale modeling for SiO<sub>2</sub>etching with CHF<sub>3</sub>/Ar and CF<sub>4</sub>/Ar plasmas. The experiments revealed a local maximum in the etch rate for an aspect ratio around unity, i.e. the simultaneous occurrence of regular and inverse reactive ion etching lag for a given etch condition. We were able to reproduce this ARDE trend in the simulations without taking into account charging effects and the polymer layer thickness, suggesting shadowing and diffuse reflection of neutrals as the primary underlying mechanisms. Subsequently, we explored four methods with the simulations to regulate ARDE, by varying the incident plasma species fluxes, the amount of polymer deposition, the ion energy and angular distribution and the initial hardmask sidewall angle, for which the latter was found to be promising in particular. Although our study focusses on feature dimensions characteristic to metrology marks and back-end-of-the-line integration, the obtained insights have a broader relevance, e.g. to the patterning of advanced nodes. Additionally, this work supports the insight that physisorption may be more important in plasma etching at room temperature than originally thought, in line with other recent studies, a topic on which we recommend further research.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001021250100001 Publication Date 2023-06-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.8 Times cited Open Access Not_Open_Access
Notes P Vanraes acknowledges funding by ASML for the project ‘Computational simulation of plasma etching of trench structures’. P Vanraes and A Bogaerts want to express their gratitude to Mark J Kushner (University of Michigan) for the sharing of the HPEM and MCFPM codes, and for the interesting exchange of views. P Vanraes wishes to thank Violeta Georgieva and Stefan Tinck for the fruitful discussions on the HPEM code, Yu-Ru Zhang for an example of the CCP reactor code and Karel Venken for his technical help with the server maintenance and use. S P Venugopalan and M Besemer wish to thank Luigi Scaccabarozzi, Sander Wuister, Coen Verschuren, Michael Kubis, Kuan-Ming Chen, Ruben Maas, Huaichen Zhang and Julien Mailfert (ASML) for the insightful discussions. Approved Most recent IF: 3.8; 2023 IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:197760 Serial 8811
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Author Smith, G.J.; Diomede, P.; Gibson, A.R.; Doyle, S.J.; Guerra, V.; Kushner, M.J.; Gans, T.; Dedrick, J.P.
Title Low-pressure inductively coupled plasmas in hydrogen : impact of gas heating on the spatial distribution of atomic hydrogen and vibrationally excited states Type A1 Journal article
Year 2024 Publication (up) Plasma sources science and technology Abbreviated Journal
Volume 33 Issue 2 Pages 025002-25020
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Non-equilibrium inductively coupled plasmas (ICPs) operating in hydrogen are of significant interest for applications including large-area materials processing. Increasing control of spatial gas heating, which drives the formation of neutral species density gradients and the rate of gas-temperature-dependent reactions, is critical. In this study, we use 2D fluid-kinetic simulations with the Hybrid Plasma Equipment Model to investigate the spatially resolved production of atomic hydrogen in a low-pressure planar ICP operating in pure hydrogen (10-20 Pa or 0.075-0.15 Torr, 300 W). The reaction set incorporates self-consistent calculation of the spatially resolved gas temperature and 14 vibrationally excited states. We find that the formation of neutral-gas density gradients, which result from spatially non-uniform electrical power deposition at constant pressure, can drive significant variations in the vibrational distribution function and density of atomic hydrogen when gas heating is spatially resolved. This highlights the significance of spatial gas heating on the production of reactive species in relatively high-power-density plasma processing sources.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001154851700001 Publication Date 2024-01-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.8 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 3.8; 2024 IF: 3.302
Call Number UA @ admin @ c:irua:203866 Serial 9054
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Author Albrechts, M.; Tsonev, I.; Bogaerts, A.
Title Investigation of O atom kinetics in O2plasma and its afterglow Type A1 Journal Article
Year 2024 Publication (up) Plasma Sources Science and Technology Abbreviated Journal Plasma Sources Sci. Technol.
Volume 33 Issue 4 Pages 045017
Keywords A1 Journal Article; oxygen plasma, pseudo-1D plug-flow kinetic model, O atoms, low-pressure validation, atmospheric pressure microwave torch; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract We have developed a comprehensive kinetic model to study the O atom kinetics in an O<sub>2</sub>plasma and its afterglow. By adopting a pseudo-1D plug-flow formalism within the kinetic model, our aim is to assess how far the O atoms travel in the plasma afterglow, evaluating its potential as a source of O atoms for post-plasma gas conversion applications. Since we could not find experimental data for pure O<sub>2</sub>plasma at atmospheric pressure, we first validated our model at low pressure (1–10 Torr) where very good experimental data are available. Good agreement between our model and experiments was achieved for the reduced electric field, gas temperature and the densities of the dominant neutral species, i.e. O<sub>2</sub>(a), O<sub>2</sub>(b) and O. Subsequently, we confirmed that the chemistry set is consistent with thermodynamic equilibrium calculations at atmospheric pressure. Finally, we investigated the O atom densities in the O<sub>2</sub>plasma and its afterglow, for which we considered a microwave O<sub>2</sub>plasma torch, operating at a pressure between 0.1 and 1 atm, for a flow rate of 20 slm and an specific energy input of 1656 kJ mol<sup>−1</sup>. Our results show that for both pressure conditions, a high dissociation degree of ca. 92% is reached within the discharge. However, the O atoms travel much further in the plasma afterglow for<italic>p</italic>= 0.1 atm (9.7 cm) than for<italic>p</italic>= 1 atm (1.4 cm), attributed to the longer lifetime (3.8 ms at 0.1 atm vs 1.8 ms at 1 atm) resulting from slower three-body recombination kinetics, as well as a higher volumetric flow rate.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001209453500001 Publication Date 2024-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.8 Times cited Open Access
Notes This research was supported by the Horizon Europe Framework Program ‘Research and Innovation Actions’ (RIA), Project CANMILK (Grant No. 101069491). Approved Most recent IF: 3.8; 2024 IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:205920 Serial 9125
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Author Borah, R.; Kumar, A.; Samantaray, M.; Desai, A.; Tseng, F.-G.
Title Photothermal heating of Au nanorods and nanospheres : temperature characteristics and strength of convective forces Type A1 Journal article
Year 2023 Publication (up) Plasmonics Abbreviated Journal
Volume 18 Issue 4 Pages 1449-1465
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The nanoscale photothermal effect and the optofluidic convection around plasmonic nanoparticles drive the application of such nanoparticles in micro-environment. In this work, heat transfer and fluid flow around Au nanospheres and nanorods in water medium under continuous and pulsed wave laser irradiance was investigated using an FEM based numerical framework. Au nanospheres of a wide range of diameter: 40 nm = Diameter (D) = 180 nm and relatively large nanorods (diameter: 50 nm) with varying aspect ratio (1 = Aspect ratio (A) = 5) and orientation (0 degrees = ? = 90 degrees, ? = 0 degrees, 90 degrees) with respect to the incident EM radiation were investigated for continuous wave (CW) and pulsed wave laser. It was found that although nanorods can attain much higher temperature than nanospheres, orientation of a nanorod is an important factor to be carefully considered in applications. In micro-scale spherical and hemispherical confinements (diameter < 14.4 p.m), the convective velocity fields around nanoparticles is in the order of 10-9 m/s, with only a weak effect of the slip or no-slip boundary condition on the confining walls. Importantly, the size of the confinement has a strong effect leading to an order of magnitude stronger convection for 14.4 p.m (diameter) spherical confinement as compared to 3.6 p.m confinement. Additionally close proximity of the nanoparticles to the confining walls strongly reduces (by an order of magnitude) the convective currents. The results reported herein provides important insights for the use of photothermal nanoparticles in microscale confined space (e.g. cellular environment) for applications such as optical tweezers, photoporation, etc.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000985445100001 Publication Date 2023-05-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1557-1955; 1557-1963 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 3; 2023 IF: 2.139
Call Number UA @ admin @ c:irua:197380 Serial 8914
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Author van Oeffelen, L.; Van Roy, W.; Idrissi, H.; Charlier, D.; Lagae, L.; Borghs, G.
Title Ion current rectification, limiting and overlimiting conductances in nanopores Type A1 Journal article
Year 2015 Publication (up) PLoS ONE Abbreviated Journal Plos One
Volume 10 Issue 10 Pages e0124171
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Previous reports on Poisson-Nernst-Planck (PNP) simulations of solid-state nanopores have focused on steady state behaviour under simplified boundary conditions. These are Neumann boundary conditions for the voltage at the pore walls, and in some cases also Donnan equilibrium boundary conditions for concentrations and voltages at both entrances of the nanopore. In this paper, we report time-dependent and steady state PNP simulations under less restrictive boundary conditions, including Neumann boundary conditions applied throughout the membrane relatively far away from the nanopore. We simulated ion currents through cylindrical and conical nanopores with several surface charge configurations, studying the spatial and temporal dependence of the currents contributed by each ion species. This revealed that, due to slow co-diffusion of oppositely charged ions, steady state is generally not reached in simulations or in practice. Furthermore, it is shown that ion concentration polarization is responsible for the observed limiting conductances and ion current rectification in nanopores with asymmetric surface charges or shapes. Hence, after more than a decade of collective research attempting to understand the nature of ion current rectification in solid-state nanopores, a relatively intuitive model is retrieved. Moreover, we measured and simulated current-voltage characteristics of rectifying silicon nitride nanopores presenting overlimiting conductances. The similarity between measurement and simulation shows that overlimiting conductances can result from the increased conductance of the electric double-layer at the membrane surface at the depletion side due to voltage-induced polarization charges.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000354916100012 Publication Date 2015-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited 11 Open Access
Notes Approved Most recent IF: 2.806; 2015 IF: 3.234
Call Number c:irua:126366 Serial 1744
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Author Duarte-Neto, P.; Stosic, B.; Stosic, T.; Lessa, R.; Milošević, M.V.; Stanley, H.E.
Title Multifractal properties of a closed contour : a peek beyond the shape analysis Type A1 Journal article
Year 2014 Publication (up) PLoS ONE Abbreviated Journal Plos One
Volume 9 Issue 12 Pages e115262
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract In recent decades multifractal analysis has been successfully applied to characterize the complex temporal and spatial organization of such diverse natural phenomena as heartbeat dynamics, the dendritic shape of neurons, retinal vessels, rock fractures, and intricately shaped volcanic ash particles. The characterization of multifractal properties of closed contours has remained elusive because applying traditional methods to their quasi-one-dimensional nature yields ambiguous answers. Here we show that multifractal analysis can reveal meaningful and sometimes unexpected information about natural structures with a perimeter well-defined by a closed contour. To this end, we demonstrate how to apply multifractal detrended fluctuation analysis, originally developed for the analysis of time series, to an arbitrary shape of a given study object. In particular, we show the application of the method to fish otoliths, calcareous concretions located in fish's inner ear. Frequently referred to as the fish's “black box”, they contain a wealth of information about the fish's life history and thus have recently attracted increasing attention. As an illustrative example, we show that a multifractal approach can uncover unexpected relationships between otolith contours and size and age of fish at maturity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000347239900030 Publication Date 2014-12-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited 6 Open Access
Notes ; Funding: This work was supported by CNPq, Brazil (Projects No. 201506/2011-4, No. 303251/2010-7, and No. 306719/2012-6). MVM acknowledges support from Flemish Science Foundation (FWO-Vlaanderen) and CAPES PVE action No. BEX1392/ 11-5. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; Approved Most recent IF: 2.806; 2014 IF: 3.234
Call Number UA @ lucian @ c:irua:123770 Serial 2218
Permanent link to this record
 

 
Author Kamaraj, B.; Bogaerts, A.
Title Structure and function of p53-DNA complexes with inactivation and rescue mutations : a molecular dynamics simulation study Type A1 Journal article
Year 2015 Publication (up) PLoS ONE Abbreviated Journal Plos One
Volume 10 Issue 10 Pages e0134638
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The tumor suppressor protein p53 can lose its function upon DNA-contact mutations (R273C and R273H) in the core DNA-binding domain. The activity can be restored by second-site suppressor or rescue mutations (R273CT284R, R273HT284R, and R273HS240R). In this paper, we elucidate the structural and functional consequence of p53 proteins upon DNA-contact mutations and rescue mutations and the underlying mechanisms at the atomic level by means of molecular dynamics simulations. Furthermore, we also apply the docking approach to investigate the binding phenomena between the p53 protein and DNA upon DNA-contact mutations and rescue mutations. This study clearly illustrates that, due to DNA-contact mutants, the p53 structure loses its stability and becomes more rigid than the native protein. This structural loss might affect the p53-DNA interaction and leads to inhibition of the cancer suppression. Rescue mutants (R273CT284R, R273HT284R and R273HS240R) can restore the functional activity of the p53 protein upon DNA-contact mutations and show a good interaction between the p53 protein and a DNA molecule, which may lead to reactivate the cancer suppression function. Understanding the effects of p53 cancer and rescue mutations at the molecular level will be helpful for designing drugs for p53 associated cancer diseases. These drugs should be designed so that they can help to inhibit the abnormal function of the p53 protein and to reactivate the p53 function (cell apoptosis) to treat human cancer.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000359061400096 Publication Date 2015-08-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited Open Access
Notes Approved Most recent IF: 2.806; 2015 IF: 3.234
Call Number c:irua:126779 Serial 3278
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Author Domingos, J.L.C.; Peeters, F.M.; Ferreira, W.P.
Title Self-assembly and clustering of magnetic peapod-like rods with tunable directional interaction Type A1 Journal article
Year 2018 Publication (up) PLoS ONE Abbreviated Journal Plos One
Volume 13 Issue 4 Pages e0195552
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Based on extensive Langevin Dynamics simulations we investigate the structural properties of a two-dimensional ensemble of magnetic rods with a peapod-like morphology, i.e, rods consisting of aligned single dipolar beads. Self-assembled configurations are studied for different directions of the dipole with respect to the rod axis. We found that with increasing misalignment of the dipole from the rod axis, the smaller the packing fraction at which the percolation transition is found. For the same density, the system exhibits different aggregation states for different misalignment. We also study the stability of the percolated structures with respect to temperature, which is found to be affected by the microstructure of the assembly of rods.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited Open Access
Notes Approved Most recent IF: 2.806
Call Number UA @ lucian @ c:irua:150778UA @ admin @ c:irua:150778 Serial 4977
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Author Mannaerts, D.; Faes, E.; Cos, P.; Briedé, J.J.; Gyselaers, W.; Cornette, J.; Gorbanev, Y.; Bogaerts, A.; Spaanderman, M.; Van Craenenbroeck, E.; Jacquemyn, Y.; Torrens, C.
Title Oxidative stress in healthy pregnancy and preeclampsia is linked to chronic inflammation, iron status and vascular function Type University Hospital Antwerp
Year 2018 Publication (up) PLoS ONE Abbreviated Journal Plos One
Volume 13 Issue 9 Pages e0202919
Keywords University Hospital Antwerp; A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Translational Pathophysiological Research (TPR)
Abstract Background

During normal pregnancy, placental oxidative stress (OS) is present during all three trimesters and is necessary to obtain normal cell function. However, if OS reaches a certain level, pregnancy complications might arise. In preeclampsia (PE), a dangerous pregnancy specific hypertensive disorder, OS induced in the ischemic placenta causes a systemic inflammatory response and activates maternal endothelial cells. In this study, we aimed to quantify superoxide concentrations (as a measure of systemic OS) using electron paramagnetic resonance (EPR) and correlate them to markers of systemic inflammation, iron status and vascular function.

Methods

Fifty-nine women with a healthy pregnancy (HP), 10 non-pregnant controls (NP) and 28 PE patients (32±3.3weeks) were included. During HP, blood samples for superoxide, neutrophil to lymphocyte ratio (NLR), mean platelet volume (MPV) and iron status were taken at 10, 25 and 39 weeks. Vascular measurements for arterial stiffness (carotid-femoral pulse wave velocity (CF-PWV), augmentation index (AIx), augmentation Pressure (AP)) and microvascular endothelial function (reactive hyperemia index (RHI)) were performed at 35 weeks. In PE, all measurements were performed at diagnosis. CMH (1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine) was used as spin probe for EPR, since the formed CM radical

corresponds to the amount of superoxide.

Results

Superoxide concentration remains stable during pregnancy (p = 0.92), but is significantly higher compared to the NP controls (p<0.0001). At 25 weeks, there is a significant positive correlation between superoxide and ferritin concentration. (p = 0.04) In PE, superoxide, systemic inflammation and iron status are much higher compared to HP (all p<0.001). During HP, superoxide concentrations correlate significantly with arterial stiffness (all p<0.04), while in PE superoxide is significantly correlated to microvascular endothelial function (p = 0.03).

Conclusions

During HP there is an increased but stable oxidative environment, which is correlated to ferritin concentration. If superoxide levels increase, there is an augmentation in arterial stiffness. In PE pregnancies, systemic inflammation and superoxide concentrations are higher and result in a deterioration of endothelial function. Together, these findings support the hypothesis that vascular function is directly linked to the amount of OS and that measurement of OS in combination with vascular function tests might be used in the prediction of PE.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000444355500010 Publication Date 2018-09-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited 15 Open Access OpenAccess
Notes This study is part of a PhD-thesis which is supported by the University of Antwerp and the Department Obstetrics and Gynaecology of the Antwerp University Hospital. The University of Antwerp provides the earnings for the principal investigator (DM) who is responsible for the design of the study, data collection and interpretation and writing of the manuscript. The Antwerp University Hospital supports the financial part of data collection. EMVC is supported by the fund for scientific research-Flanders (FWO) as senior clinical investigator. Approved Most recent IF: 2.806
Call Number PLASMANT @ plasmant @c:irua:153802c:irua:153644 Serial 5048
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Author Smits, M.; Vanpachtenbeke, F.; Horemans, B.; De Wael, K.; Hauchecorne, B.; Van Langenhove, H.; Demeestere, K.; Lenaerts, S.
Title Effect of operating and sampling conditions on the exhaust gas composition of small-scale power generators Type A1 Journal article
Year 2012 Publication (up) PLoS ONE Abbreviated Journal Plos One
Volume 7 Issue 3 Pages e32825-e32825,10
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL)
Abstract Small stationary diesel engines, like in generator sets, have limited emission control measures and are therefore responsible for 44% of the particulate matter (PM) emissions in the United States. The diesel exhaust composition depends on operating conditions of the combustion engine. Furthermore, the measurements are influenced by the used sampling method. This study examines the effect of engine loading and exhaust gas dilution on the composition of small-scale power generators. These generators are used in different operating conditions than road-transport vehicles, resulting in different emission characteristics. Experimental data were obtained for gaseous volatile organic compounds (VOC) and PM mass concentration, elemental composition and nitrate content. The exhaust composition depends on load condition because of its effect on fuel consumption, engine wear and combustion temperature. Higher load conditions result in lower PM concentration and sharper edged particles with larger aerodynamic diameters. A positive correlation with load condition was found for K, Ca, Sr, Mn, Cu, Zn and Pb adsorbed on PM, elements that originate from lubricating oil or engine corrosion. The nitrate concentration decreases at higher load conditions, due to enhanced nitrate dissociation to gaseous NO at higher engine temperatures. Dilution on the other hand decreases PM and nitrate concentration and increases gaseous VOC and adsorbed metal content. In conclusion, these data show that operating and sampling conditions have a major effect on the exhaust gas composition of small-scale diesel generators. Therefore, care must be taken when designing new experiments or comparing literature results.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000303836500012 Publication Date 2012-03-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited 5 Open Access
Notes ; ; Approved Most recent IF: 2.806; 2012 IF: 3.730
Call Number UA @ admin @ c:irua:96545 Serial 5581
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Author Tilleman, L.; De Henau, S.; Pauwels, M.; Nagy, N.; Pintelon, I.; Braeckman, B.P.; De Wael, K.; Van Doorslaer, S.; Adriaensen, D.; Timmermans, J.-P.; Moens, L.; Dewilde, S.
Title An N-myristoylated globin with a redox-sensing function that regulates the defecation cycle in Caenorhabditis elegans Type A1 Journal article
Year 2012 Publication (up) PLoS ONE Abbreviated Journal Plos One
Volume 7 Issue 12 Pages e48768-9
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Globins occur in all kingdoms of life where they fulfill a wide variety of functions. In the past they used to be primarily characterized as oxygen transport/storage proteins, but since the discovery of new members of the globin family like neuroglobin and cytoglobin, more diverse and complex functions have been assigned to this heterogeneous family. Here we propose a function for a membrane-bound globin of C. elegans, GLB-26. This globin was predicted to be myristoylated at its N-terminus, a post-translational modification only recently described in the globin family. In vivo, this globin is found in the membrane of the head mesodermal cell and in the tail stomato-intestinal and anal depressor muscle cells. Since GLB-26 is almost directly oxidized when exposed to oxygen, we postulate a possible function as electron transfer protein. Phenotypical studies show that GLB-26 takes part in regulating the length of the defecation cycle in C. elegans under oxidative stress conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000313236200008 Publication Date 2012-12-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited 6 Open Access
Notes ; SDH is a Ph.D. fellow of the Fund for Scientific Research (FWO). Financial support to SD and LM was provided by the University of Antwerp (BOF UA TOP 2006) and to SD, LM, BPB, by FWO project G.0247.09. The UltraVIEW VoX spinning disk confocal microscope was purchased with support of the Hercules Foundation (Hercules Type 1: AUHA 09/001). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; Approved Most recent IF: 2.806; 2012 IF: 3.730
Call Number UA @ admin @ c:irua:102591 Serial 5741
Permanent link to this record
 

 
Author Wambacq, E.; Alloul, A.; Grunert, O.; Carrette, J.; Vermeir, P.; Spanoghe, J.; Sakarika, M.; Vlaeminck, S.E.; Haesaert, G.
Title Aerobes and phototrophs as microbial organic fertilizers : exploring mineralization, fertilization and plant protection features Type A1 Journal article
Year 2022 Publication (up) PLoS ONE Abbreviated Journal Plos One
Volume 17 Issue 2 Pages e0262497-15
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Organic fertilizers and especially microbial biomass, also known as microbial fertilizer, can enable a paradigm shift to the conventional fertilizer-to-food chain, particularly when produced on secondary resources. Microbial fertilizers are already common practice (e.g. Bloom® and Synagro); yet microbial fertilizer blends to align the nutrient release profile to the plant’s needs are, thus far, unexplored. Moreover, most research only focuses on direct fertilization effects without considering added value properties, such as disease prevention. This study has explored three promising types of microbial fertilizers, namely dried biomass from a consortium of aerobic heterotrophic bacteria, a microalga (Arthrospira platensis) and a purple non-sulfur bacterium (Rhodobacter sphaeroides). Mineralization and nitrification experiments showed that the nitrogen mineralization profile can be tuned to the plant’s needs by blending microbial fertilizers, without having toxic ammonium peaks. In a pot trial with perennial ryegrass (Lolium perenne L.), the performance of microbial fertilizers was similar to the reference organic fertilizer, with cumulative dry matter yields of 5.6–6.7 g per pot. This was confirmed in a pot trial with tomato (Solanum lycopersicum L.), showing an average total plant length of 90–99 cm after a growing period of 62 days for the reference organic fertilizer and the microbial fertilizers. Moreover, tomato plants artificially infected with powdery mildew (Oidium neolycopersici), a devastating disease for the horticultural industry, showed reduced disease symptoms when A. platensis was present in the growing medium. These findings strengthen the application potential of this novel class of organic fertilizers in the bioeconomy, with a promising match between nutrient mineralization and plant requirements as well as added value in crop protection.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000775890100025 Publication Date 2022-02-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.7
Call Number UA @ admin @ c:irua:185568 Serial 7122
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Author Gielis, J.; Caratelli, D.; Fougerolle, Y.; Ricci, P.E.; Tavkelidze, I.; Gerats, T.
Title Universal natural shapes : from unifying shape description to simple methods for shape analysis and boundary value problems Type A1 Journal article
Year 2012 Publication (up) PLoS ONE Abbreviated Journal
Volume 7 Issue 9 Pages e29324-11
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Gielis curves and surfaces can describe a wide range of natural shapes and they have been used in various studies in biology and physics as descriptive tool. This has stimulated the generalization of widely used computational methods. Here we show that proper normalization of the Levenberg-Marquardt algorithm allows for efficient and robust reconstruction of Gielis curves, including self-intersecting and asymmetric curves, without increasing the overall complexity of the algorithm. Then, we show how complex curves of k-type can be constructed and how solutions to the Dirichlet problem for the Laplace equation on these complex domains can be derived using a semi-Fourier method. In all three methods, descriptive and computational power and efficiency is obtained in a surprisingly simple way.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000309517500001 Publication Date 2012-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:102202 Serial 8711
Permanent link to this record
 

 
Author Bjørnåvold, A.; David, M.; Mermet-Bijon, V.; Beaumais, O.; Crastes dit Sourd, R.; Van Passel, S.; Martinet, V.
Title To tax or to ban? A discrete choice experiment to elicit public preferences for phasing out glyphosate use in agriculture Type A1 Journal article
Year 2023 Publication (up) PLoS ONE Abbreviated Journal
Volume 18 Issue 3 Pages 1-12
Keywords A1 Journal article; Economics; Engineering Management (ENM)
Abstract In 2023, the European Union will vote on the reauthorization of glyphosate use, renewed in 2017 despite concern on impacts on the environment and public health. A ban is supported by several Member States but rejected by most farmers. What are citizens’ preferences to phase out glyphosate? To assess whether taxation could be an alternative to a ban, we conducted a discrete choice experiment in five European countries. Our results reveal that the general public is strongly willing to pay for a reduction in glyphosate use. However, while 75.5% of respondents stated to support a ban in the pre-experimental survey, experimental results reveal that in 73.35% of cases, earmarked taxation schemes are preferred when they lead to a strong reduction in glyphosate use for an increase in food price lower than that induced by a ban. When glyphosate reduction is balanced against its costs, a tax may be preferred.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000985134400084 Publication Date 2023-03-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:196999 Serial 9236
Permanent link to this record
 

 
Author Moiseeva, E.O.; Trashin, S.; Korostei, Y.S.; Khan, S.U.; Kosov, A.D.; De Wael, K.; Dubinina, T.V.; Tomilova, L.G.
Title Electrochemical and spectroelectrochemical studies of tert-butyl-substituted aluminum phthalocyanine Type A1 Journal article
Year 2021 Publication (up) Polyhedron Abbreviated Journal Polyhedron
Volume 200 Issue Pages 115136
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Tetra-tert-butylphthalocyanine aluminum (III) chloride was studied by voltammetric and potential-resolved spectroelectrochemical methods in a non-coordinating solvent o-dichlorobenzene. Five redox transitions were found including two oxidation waves at 0.18 and 0.90 V and three reduction waves at −1.28, −1.65, and −2.63 V vs. Fc+/Fc. Electrochemical reversibility of the first oxidation and reduction processes was assessed by using the diagnostic criteria of cyclic voltammetry. First comprehensive spectroelectrochemical characterization of oxidation of the aluminum phthalocyanine is reported. Moreover, potential-resolved spectroelectrochemical titration revealed strong influence of aggregation on the UV–vis spectra and the half-wave potentials of the first oxidation transition and disclosed the presence of the partially oxidized complex in the initial solution, which noticeably affected the spectrum of the neutral form.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000640386000006 Publication Date 2021-03-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0277-5387 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.926 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 1.926
Call Number UA @ admin @ c:irua:176389 Serial 7860
Permanent link to this record
 

 
Author Briers, J.; Eevers, W.; Cos, P.; Geise, H.J.; Mertens, R.; Nagels, P.; Zhang, X.B.; Van Tendeloo, G.; Herrebout, W.; van der Veken, B.
Title Molecular orientation and conductivity in highly oriented poly(p-phenylene vinylene) Type A1 Journal article
Year 1994 Publication (up) Polymer Abbreviated Journal Polymer
Volume 35 Issue Pages 4569-4572
Keywords A1 Journal article; Molecular Spectroscopy (MolSpec); Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Guildford Editor
Language Wos A1994PM11600014 Publication Date 2003-06-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-3861; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.562 Times cited 16 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:8539 Serial 2180
Permanent link to this record
 

 
Author Idaszek, J.; Brynk, T.; Jaroszewicz, J.; Vanmeert, F.; Bruinink, A.; Swieszkowski, W.
Title Investigation of mechanical properties of porous composite scaffolds with tailorable degradation kinetics after in vitro degradation using digital image correlation Type A1 Journal article
Year 2017 Publication (up) Polymer composites Abbreviated Journal
Volume 38 Issue 11 Pages 2402-2410
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Tissue engineering combines artificial scaffolds and living cells in order to reconstruct damaged tissues and organs. The biodegradable scaffolds should maintain their mechanical properties during first stages of the regeneration. The aim of this study was to investigate the extent the degradation affects the mechanical stability of novel biodegradable composite scaffolds in relation to their composition. The scaffolds were made using fused deposition modeling. They were composed of ternary composites containing poly(epsilon-caprolactone) (PCL), 5 wt% of tricalcium phosphate (TCP) and 5, 15, and 25 wt% of poly(lactide-co-glycolide) (PLGA). Scaffolds made of pristine PCL and binary composite PCL-TCP were tested as reference samples. The degradation experiment was carried out in simulated body fluid at 37 degrees C for 12 weeks. Mechanical tests were carried out in a mechanical tester. Strain was measured using digital image correlation and crossbar displacement. Chemical composition had a significant effect on initial mechanical properties and their changes during degradation. The initial apparent Young's modulus of ternary composite scaffolds was two times higher than that of PCL-TCP. Higher PLGA concentration yielded faster decrease of the mechanical properties. At the end of the experiment, there were no significant differences of the modulus among all tested materials although degradation of the ternary composite scaffolds was significantly advanced. (C) 2015 Society of Plastics Engineers
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000415812000008 Publication Date 2015-10-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0272-8397 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:147728 Serial 8127
Permanent link to this record
 

 
Author Das, P.P.; Guzzinati, G.; Coll, C.; Gomez Perez, A.; Nicolopoulos, S.; Estrade, S.; Peiro, F.; Verbeeck, J.; Zompra, A.A.; Galanis, A.S.
Title Reliable Characterization of Organic & Pharmaceutical Compounds with High Resolution Monochromated EEL Spectroscopy Type A1 Journal article
Year 2020 Publication (up) Polymers Abbreviated Journal Polymers-Basel
Volume 12 Issue 7 Pages 1434
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Organic and biological compounds (especially those related to the pharmaceutical industry) have always been of great interest for researchers due to their importance for the development of new drugs to diagnose, cure, treat or prevent disease. As many new API (active pharmaceutical ingredients) and their polymorphs are in nanocrystalline or in amorphous form blended with amorphous polymeric matrix (known as amorphous solid dispersion—ASD), their structural identification and characterization at nm scale with conventional X-Ray/Raman/IR techniques becomes difficult. During any API synthesis/production or in the formulated drug product, impurities must be identified and characterized. Electron energy loss spectroscopy (EELS) at high energy resolution by transmission electron microscope (TEM) is expected to be a promising technique to screen and identify the different (organic) compounds used in a typical pharmaceutical or biological system and to detect any impurities present, if any, during the synthesis or formulation process. In this work, we propose the use of monochromated TEM-EELS, to analyze selected peptides and organic compounds and their polymorphs. In order to validate EELS for fingerprinting (in low loss/optical region) and by further correlation with advanced DFT, simulations were utilized.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000556786700001 Publication Date 2020-06-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2073-4360 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.364 Times cited 6 Open Access OpenAccess
Notes C.C., F.P., S.E. acknowledges the Spanish government for projects MAT2016-79455-P, Research Network RED2018-102609-T and the FPI (BES-2017-080045) grant of Ministerio de Ciència, Innovación y Universidades. G.G. acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek—Vlaanderen (FWO). P.P.D., A.G.P., S.N. gratefully acknowledge much helpful discussion on EELS study for organic compounds with Dr. Andrey Chuvilin (CIC NANOGUNE, Donostia—San Sebastian, Spain). The authors also acknowledge Raúl Arenal (University de Zaragoza, Spain) for useful discussion on EELS. The authors acknowledge also Ulises Julio Amador Elizondo (Universidad CEU San Pablo, Spain) for kindly provide the aripiprazole and piroxicam samples for EELS study.; EUSMI_TA; Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:170603 Serial 6400
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Author Al-Emam, E.; Beltran, V.; De Meyer, S.; Nuyts, G.; Wetemans, V.; De Wael, K.; Caen, J.; Janssens, K.
Title Removal of a past varnish treatment from a 19th-century Belgian wall painting by means of a solvent-loaded double network hydrogel Type A1 Journal article
Year 2021 Publication (up) Polymers Abbreviated Journal Polymers-Basel
Volume 13 Issue 16 Pages 2651-20
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab); Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract Polymeric materials have been used by painting conservator-restorers as consolidants and/or varnishes for wall paintings. The application of these materials is carried out when confronting loose paint layers or as a protective coating. However, these materials deteriorate and cause physiochemical alterations to the treated surface. In the past, the monumental neo-gothic wall painting 'The Last Judgment' in the chapel of Sint-Jan Berchmanscollege in Antwerp, Belgium was treated with a synthetic polymeric material. This varnish deteriorated significantly and turned brown, obscuring the paint layers. Given also that the varnish was applied to some parts of the wall painting and did not cover the entire surface, it was necessary to remove it in order to restore the original appearance of the wall painting. Previous attempts carried out by conservator-restorers made use of traditional cleaning methods, which led to damage of the fragile paint layers. Therefore, gel cleaning was proposed as a less invasive and more controllable method for gently softening and removing the varnish. The work started by identifying the paint stratigraphy and the deteriorated varnish via optical microscopy (OM), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. A polyvinyl alcohol-borax/agarose (PVA-B/AG) hydrogel loaded with a number of solvents/solvent mixtures was employed in a series of tests to select the most suitable hydrogel composite. By means of the hydrogel composite loaded with 10% propylene carbonate, it was possible to safely remove the brown varnish layer. The results were verified by visual examinations (under visible light 'VIS' and ultraviolet light 'UV') as well as OM and FTIR spectroscopy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000690248000001 Publication Date 2021-08-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2073-4360 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.364 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.364
Call Number UA @ admin @ c:irua:181567 Serial 8470
Permanent link to this record
 

 
Author Chukalina, M.; Simionovici, A.S.; Snigirev, A.; Drakopoulos, M.; Snigireva, I.; Adams, F.; Janssens, K.
Title X-ray fluorescence microtomography Type A3 Journal article
Year 2001 Publication (up) Poverhnost Abbreviated Journal
Volume 3 Issue Pages 40-43
Keywords A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:34058 Serial 5914
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Author Vazquez, C.; Martin Palacios, O.; Darchuk, L.; Marco Parra, L.-M.
Title Compositional study of prehistoric pigments (Carriqueo rock shelter, Argentina) by synchrotron radiation X-ray diffraction Type A1 Journal article
Year 2010 Publication (up) Powder diffraction Abbreviated Journal
Volume 25 Issue 3 Pages 264-269
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this work synchrotron radiation X-ray diffraction technique was successfully applied for the analysis of pigments found in excavation at Carriqueo rock shelter, Neuquen, Argentina. The pigment samples of orange, red, and brown shades were collected from different levels of this archaeological site and compared with a suspected source of provenance (La Oficina creek). X-ray diffraction patterns of several yellowish, reddish, and red pigments showed the presence of haematite, goethite, kaolinite, and quartz. The majority of Carriqueo collected samples belonged to the same group of the suspected source, having haematite and quartz as main crystalline phases. The results indicate that the raw material from La Oficina is the source of most of the pigments found at Carriqueo. The present work helps us to understand the strategy of supplying raw materials by human groups in the North Patagonia region. (C) 2010 International Centre for Diffraction Data. [DOI: 10.1154/1.3478884]
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000282386500009 Publication Date 2010-09-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0885-7156 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:95582 Serial 7717
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Author Gonzalez-Quiroga, A.; Kulkarni, S.R.; Vandewalle, L.; Perreault, P.; Goel, C.; Heynderickx, G.J.; van Geem, K.M.; Marin, G.B.
Title Azimuthal and radial flow patterns of 1g-Geldart B-type particles in a gas-solid vortex reactor Type A1 Journal article
Year 2019 Publication (up) Powder technology Abbreviated Journal
Volume 354 Issue Pages 410-422
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Processes requiring intensive interfacial momentum, mass and heat exchange between gases and particulate solids can be greatly enhanced by operating in a centrifugal field. This is realized in the Gas-Solid Vortex Reactor (GSVR) with centrifugal accelerations up to two orders of magnitude higher than the Earth's gravitational acceleration. Here, the flow patterns of two 1g-Geldart B-type particles are experimentally assessed, over the gas inlet velocity range 82–126 m s−1, in an 80 mm diameter and 15 mm height GSVR. The particles are monosized aluminum spheres of 0.5 mm diameter, and walnut shell in the sieve fraction 0.50–0.56 mm and aspect ratio 1.3 ± 0.2. Two dimensional Particle Image Velocimetry combined with Digital Image Analysis and pressure measurements revealed that periodic fluctuations in solids azimuthal and radial velocity between gas inlet slots are strongly related to the average solids azimuthal velocity and bed uniformity. Aluminum particles feature steeper changes in azimuthal velocity and more attenuated changes in radial velocity than walnut shell particles. Within the assessed gas inlet velocity range the solids bed of aluminum exhibits average azimuthal velocities and bed voidages 40–50% and ≈10% lower than those of walnut shell. The aerodynamic response time of the particles, i.e. ρsdp2/18μg, emerged as an important parameter to assess the influence of the carrier gas jet on the radial deflection of the particles and the interaction solids bed-outer wall. Too low aerodynamic response time relates to nonuniformity in bed voidage due to solids radial velocity fluctuations. Excessive aerodynamic response time indicates low solids azimuthal velocities due to solids bed-outer wall friction.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000490625500041 Publication Date 2019-06-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-5910 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:162120 Serial 7543
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