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Author Jiang, J.
Title Ginzburg-Landau dynamical simulations on the nonreciprocal transport properties of two-dimensional superconductors Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages XII, 79 p.
Keywords Doctoral thesis; Condensed Matter Theory (CMT)
Abstract The nonreciprocal charge transport property which depends on the polarity of the applied current, such as the diode effect and the rectification effect, is of great importance for both theoretical research and engineering application. The nonreciprocal transport property in superconductors generally requires to break both the spatial inversion symmetry and the time-reversal symmetry, and therefore becomes one of the fundamental issues in superconductivity. Of particular interest, the superconducting diode effect, which exhibits one-way superconductivity, can potentially be applied to dissipationless diode devices, as a consequence has received extensive attention in recent years. In this Ph. D thesis, we simulate vortex dynamics with heat dissipation by numerically solving time-dependent Ginzburg-Landau equations and heat transfer equation. The nonreciprocal transport properties of the following three superconducting systems are studied. We study a superconducting film patterned with a conformal pinning array and find a giant rectification effect which is consistent with the experimental observation. In presence of the funneling effect due to the geometry of the conformal pinning array, Joule heating of the accumulating vortices creates hot spots and drives the sample to the normal state. Meanwhile, the density gradient of vortex does not match the gradient of pinning. The two mechanisms together lead to the giant rectification effect. We study the nonreciprocal charge transport property in a pinning-free superconducting nano-ring. We systematically calculate the response of the ratchet signal to various parameters in both D.C. and A.C. currents. By analyzing the vortex potential, we find that the nonreciprocal transport property is caused by the asymmetry potential barriers for vortex entry and exit. We study a superconductor/nanoscale-magnetic-dot hybrid structure. It takes advantage of the external current to control the nucleation of vortex-antivortex pairs, and can produce superconducting diode effect without applied magnetic fields. Our vortex dynamics simulation details the progress of the superconducting-normal phase transition due to motion of vortex pairs and heat dissipation. The nonreciprocal transport properties of the above three systems are all based on the broken symmetry of spatial inversion, which is caused by the anisotropic pinning array, the asymmetric geometry, and the nonuniform distribution of the magnetic field, respectively. The mechanisms we discuss in this thesis do not require special property of the materials and thus can be applied to any kinds of conventional superconductors. The present studies would provide solid theoretical basis for the future design and application of the dissipationless superconducting devices.
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:188525 Serial 7168
Permanent link to this record
 
 
Author Oliveira, M.C.
Title Influence of phase-separated domains on the permeability of oxidized lipid membranes Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages 151 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Biological membranes are under constant attack of reactive oxygen and nitrogen species (RONS), which may lead to a complex mixture of nitro-oxidized lipids that are responsible for structural and dynamic changes on the membrane. Because of that, nitro-oxidized lipids are also associated with several tumors and inflammatory and neurodegenerative diseases. Moreover, lipid oxidation may induce membrane phase-separated domains, which also drastically affect the membrane function. Evidence suggests that domain interfaces are “hot spots” for pore formation, but the underlying mechanisms remain elusive. There is an urgent need for an improved understanding of oxidation-induced phase separation on membrane properties. Likewise, the molecular structure at domain interfaces still needs to be elucidated. To evaluate the effect of lipid nitro-oxidation on the permeability of single-phase (homogeneous) and phase-separated (heterogeneous) phospholipid bilayers (PLBs), we performed atomistic molecular dynamics (MD) simulations using: (1) single-phase PLBs composed of several isomers of nitrated and/or oxidized lipids; (2) phase-separated PLBs composed of coexisting liquid ordered (Lo) and liquid disordered (Ld) domains, where the Ld domain is composed of non-oxidized and/or oxidized lipids. Our results show that nitrated lipids increase the membrane permeability of single-phase PLBs by three-fold compared to oxidized lipids. In addition, we show that oxidized lipids in the presence of nitrated lipids decrease the membrane permeability, suggesting an interaction between nitrated and oxidized lipids. Overall, the permeability of single-phase and phase-separated PLBs was comparable, and the presence of oxidized lipids increases the membrane permeability only in single-phase PLBs. Despite the latter, the presence of only 1.5% of lipid aldehydes at the Lo/Ld domain interfaces of phase-separated PLBs was able to increase the membrane permeability. In consequence of this, we also performed coarse-grained MD simulations to evaluate whether lipid aldehydes have a preference to accumulate at the interface between Lo/Ld domains. Our results show that lipid aldehydes derived from mono-unsaturated lipids accumulate at the interface, but those derived from poly-unsaturated lipids remain in the Ld domain. This study is of interest for photodynamic therapy and plasma medicine for cancer treatment, to understand the effects caused by RONS in cell membranes.
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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:191039 Serial 7173
Permanent link to this record
 
 
Author Hao, Y.
Title A joint experimental-modeling study of the structure and properties of functional molecular monolayers for the control of organic crystal growth Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages xiii, 174 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Among all types of discovered crystals, those formed by organic molecules show the greatest diversity, which results from the intrinsic complexity of the organic molecules and the weak interactions between them. Even for a given compound, different crystal structures can exist. This feature is referred to as polymorphism in the modern crystallographic context and those different crystal forms are called polymorphs. In reality, the crystallization of organic molecules is often performed at the surface of a substrate, giving rise to heterogeneous crystallization. Except for the well-known catalyzing effects, the existence of substrates brings more possibilities to the polymorphic behaviors of organic molecules, promoting the formation of new polymorphs that are only stable in the vicinity of the substrates. For this reason, these new polymorphic forms are often described as substrate-induced polymorphs (SIPs). It is of great importance to understand the formation of SIPs for organic molecules as it has been reported that SIPs can show superior properties with respect to their bulk form counterparts. Up to now, most studies focus on the identifying and characterizing the presence of SIPs, which relies mainly on X-ray diffraction techniques. However, a detailed explanation about the origin of SIPs is still missing. In this work, we have combined several powerful experimental characterization techniques, including X-ray diffraction, transmission electron microscopy (TEM) and scanning tunneling microscopy (STM) in order to reach an integrated view over the formation of SIPs. These experimental studies are strongly supported by computational chemistry simulations, such as density functional theory and molecular dynamics. A big advantage of using atomistic simulations is that it enables the possibility to predict a priori the crystal structures of SIPs and to establish a posteriori the general rules for the formation of SIPs. In practice, this thesis employs state-of-art atomistic simulation approaches in order to bridge substrate-induced polymorphism with a conceptually-connected research area: the self-assembly of molecular networks (SAMNs), also called 2D crystallization. Unlike SIPs, which extend at least several molecular layers, SAMNs are composed of a single layer of molecules with ordered packing. Our simulations have enabled a more comprehensive understanding about the role of substrate during the formation of SIPs and we elucidate how the positional and orientational order of molecules propagates from the substrate to the upper 2D and even 3D crystal layers. In this way, a fundamental understanding of the substrate-induced crystallization is gained by connecting 2D and 3D crystallization using substrate-induced approaches.
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:191758 Serial 7176
Permanent link to this record
 
 
Author Loomba, V.; Pourfallah, H.; Olsen, J.E.; Einarsrud, K.E.
Title Lab-scale physical model experiments to understand the effect of particle bed on tapping flow rates Type P1 Proceeding
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages 159-170
Keywords P1 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2022-02-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-3-030-92543-7; 2367-1181; 2367-1696; 978-3-030-92546-8; 978-3-030-92544-4 ISBN Additional Links UA library record
Impact Factor Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:186090 Serial 7177
Permanent link to this record
 
 
Author Gielis, J.; Grigolia, R.
Title Lamé curves and Rvachev's R-functions Type A3 Journal article
Year 2022 Publication Sn – 1512-0066 Abbreviated Journal
Volume 37 Issue (up) Pages 1-4
Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Gielis transformations are a generalization of Lame curves. To combine domains, we can make use of the natural alliance between Lame's work and Rvachev's R-functions. A logical next step is the extension to n-valued logic dening dierent partitions.
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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:189316 Serial 7178
Permanent link to this record
 
 
Author Vanmeert, F.; De Meyer, S.; Gestels, A.; Clerici, E.A.; Deleu, N.; Legrand, S.; Van Espen, P.; Van der Snickt, G.; Alfeld, M.; Dik, J.; Monico, L.; De Nolf, W.; Cotte, M.; Gonzalez, V.; Saverwyns, S.; Depuydt-Elbaum, L.; Janssens, K.
Title Non-invasive and non-destructive examination of artists’ pigments, paints and paintings by means of X-ray imaging methods Type H1 Book chapter
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages 317-357
Keywords H1 Book chapter; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract Recent studies in which X-ray beams of (sub)micrometre to millimetre dimensions have been used for non-destructive analysis and characterization of pigments, minute paint samples and/or entire paintings from fifteenth to twentieth century artists are discussed. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging as well as with the combined use with X-ray diffraction (XRD). Microscopic XRF (μ-XRF) is a variant of the XRF method able to visualize the elemental distribution of key elements, mostly metals, on the scale from 1 μm to 100 μm present inside multi-layered micro samples taken from paintings. In the context of the characterization of artists’ pigments subjected to natural degradation, in many cases the use of methods limited to elemental analysis or imaging does not suffice to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS (microscopic X-ray absorption spectroscopy) and μ-XRD have proven themselves to be very suitable for such studies. Since microscopic investigation of a relatively limited number of minute paint samples may not yield representative information about the complete artefact they were taken from, several methods for macroscopic, non-invasive imaging have recently been developed. Combined macroscopic XRF/XRD scanning is able to provide a fairly complete overview of the inorganic pigments employed to create a work of art, to answer questions about ongoing degradation phenomena and about its authenticity. As such these newly developed non-invasive and highly specific imaging methods are of interest for many cultural heritage stakeholders.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2022-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 978-3-030-86864-2 Additional Links UA library record
Impact Factor Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:190777 Serial 7183
Permanent link to this record
 
 
Author Ysebaert, T.; Samson, R.; Denys, S.
Title Parameterisation of the drag effect of climbers depending on wind speed and LAD Type A1 Journal article
Year 2022 Publication Sustainable Cities and Society Abbreviated Journal Sustain Cities Soc
Volume 84 Issue (up) Pages 103979-12
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The implementation of green walls is increasingly seen as a strategy to tackle urban air pollution and to make cities more climate resilient. The correct description of the vegetation-wind interaction is key in describing the effect of vegetation in computational fluid dynamics (CFD) models. The accuracy of the modelled wind flow is highly linked to the uncertainty about the drag coefficient (C-d). In addition, at low wind speeds viscous drag (K) is not negligible and it should be regarded in CFD models. This research aims to address the uncertainty related to C-d and K by including the effect of climbers on both the momentum and turbulence equations in the Wilcox revised k-omega model. The change of K with increasing Reynolds number showed an increase from 5.10(-8 )m(2) up to the dynamic viscosity of air (asymptotic to 10(-5) m(2)) following a logistic function. Beyond the transition region from viscous to form drag, C-d, in the range of 0.1-1.1, declined with increasing Reynolds number following a power law function. Furthermore, the plant morphological parameters determining permeability and drag coefficient were identified. This study showed that the knowledge of viscous and shape resistance is necessary to obtain accurate statistics for air flow through vegetation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000831685500001 Publication Date 2022-06-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2210-6707 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.7 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 11.7
Call Number UA @ admin @ c:irua:189465 Serial 7187
Permanent link to this record
 
 
Author Borah, R.
Title Photoactive nanostructures : from single plasmonic nanoparticles to self-assembled films Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages xxxiv, 220 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Photoactive nanoparticles and their light-driven applications have gained tremendous scientific attention towards remediation of the global environmental problems, meeting alternative energy demands, and other new technological discoveries. The research work presented in this dissertation includes a fundamental investigation of such nanoparticles to gain deeper insights that will ultimately benefit their application. In particular, the study of plasmonic metal nanoparticles and metal oxide nanoparticles for light driven applications is the major theme of this work. The investigation begins with isolated plasmonic Au and Ag nanoparticles, followed by a natural extension to nanoparticle clusters, and then further to nanoparticle films. Next, the application of such plasmonic nanoparticle films for gaseous phase sensing of volatile organic compounds is explored. Finally, the film formation of metal-oxide nanoparticles by self-assembly is investigated for the fabrication of photoactive functional interfaces. The fundamental theoretical investigation of the isolated plasmonic nanoparticles encompasses alloy and core-shell nanostructures of Au-Ag bimetallic compositions. First, the optical properties of bimetallic alloy and core-shell nanoparticles are compared for different structures such as nanospheres, nanotriangles and nanorods. Based on the optical properties, the photothermal properties of these nanostructures are also evaluated for relevant light-driven applications. Further, to bridge the gap between the theoretical and experimental optical properties of colloidal plasmonic nanoparticles, the effect of different statistical parameters pertaining to the particle size distribution is studied. Going from isolated nanoparticles to nanoparticle clusters, the changes in the optical properties of plasmonic nanoparticles when they form finite clusters is investigated. A strong effect of clustering on the absorption intensities of the nanoparticles and hence, on the photothermal properties is found. Next, for the study of plasmonic nanoparticle infinite arrays, Au and Ag nanoparticles films are experimentally obtained by the self-assembly at the air-ethylene glycol interface. Upon further validation of the computational models with the experimental optical properties of these films, the near-field and far-field optical response of the plasmonic nanoparticle arrays is investigated. An application of the self-assembled Au nanoparticle film is then demonstrated in the sensing of volatile organic compounds (VOCs). Finally, the focus is shifted from plasmonic nanoparticles to metal oxide nanoparticles for their self-assembly at the air-water interface to obtain self-assembled films. For this, the hydrophobic functionalization of four metal oxides nanoparticles namely, TiO2, ZnO, WO3 and CuO is investigated. The insights from this work is useful for the design and fabrication of functional nanoparticles and interfaces for light driven applications.
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:189155 Serial 7188
Permanent link to this record
 
 
Author Van Hal, M.; Lenaerts, S.; Verbruggen, S.W.
Title Photocatalytic soot degradation under UV and visible light Type A1 Journal article
Year 2022 Publication Environmental Science and Pollution Research Abbreviated Journal Environ Sci Pollut R
Volume Issue (up) Pages 1-11
Keywords A1 Journal article; Engineering sciences. Technology
Abstract Particulate matter is one of the most persistent global air pollutants that is causing health problems, climate disturbance and building deterioration. A sustainable technique that is able to degrade soot using (sun)light is photocatalysis. Currently, research on photocatalytic soot oxidation focusses on large band gap TiO2-based photocatalysts and thus requires the use of UV light. It would prove useful if visible light, and thus a larger fraction of the (freely available) solar spectrum, could additionally be utilised to drive this process. In this work, a visible light-active photocatalyst, WO3, is benchmarked to TiO2 under both UV and visible light. At the same time, the versatility and drastic improvement of a recently introduced digital image-based soot degradation detection method are demonstrated. An additional step correcting for non-soot related catalyst colour changes is applied, resulting in accurate detection and quantification of soot degradation for all studied photocatalysts, even for materials such as WO3 that are inherently coloured. With this study, we aim to broaden the scope of photocatalytic soot oxidation technology to visible light-active photocatalyst. Along with this study, we provide a versatile soot degradation detection methodology based on digital image analysis that is made widely applicable.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000871854600010 Publication Date 2022-10-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0944-1344; 1614-7499 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5.8
Call Number UA @ admin @ c:irua:191275 Serial 7189
Permanent link to this record
 
 
Author van 't Veer, K.C.
Title Plasma kinetics modelling of nitrogen fixation : ammonia synthesis in dielectric barrier discharges with catalysts Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages 241 p.
Keywords Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Ammonia (NH3) synthesis is crucial for the production of artificial fertilizer and is carried out through the Haber-Bosch process. With an energy consumption of 30 GJ/t-NH3 and the emission of 2 kg-CO2/kg-NH3, ammonia is the chemical with the largest environmental footprint. Haber-Bosch operates under high pressure and high temperature conditions. Plasma technology potentially allows greener ammonia production. Dielectric barrier discharges are a popular plasma source in which a catalyst is easily incorporated. The combination of plasma and catalyst can circumvent the harsh reaction conditions of the Haber-Bosch process. Plasma kinetics modelling is used to gain insight into the mechanisms of such plasma-catalytic systems. Special attention is given to the instantaneous power absorbed by the electrons, the relevant fraction of the microdischarges and the discharge volumes. The importance of vibrational excitation is investigated. Depending on the exact discharge conditions, it was found that both the strong microdischarges and vibrational excitation can be simultaneously important for the ammonia yield. The temporal behavior of filamentary dielectric barrier discharges was explicitly taken into account. Ammonia was found to decompose during the microdischarges due to electron impact dissociation. At the same time atomic nitrogen and other excited species are created. Those reactive species recombine to ammonia in the afterglow through various elementary Eley-Rideal and Langmuir-Hinshelwood surface reaction steps with a net ammonia gain. Finally, the concept of the fraction of microdischarges was generalized. It directly represents the efficiency with which the applied electric power is transferred to each individual particle in the plasma reactor. It is argued that any type of spatial or temporal non-uniformity of the plasma will cause unequal treatment of the gas molecules in the reactor, corresponding to a lower efficiency at which the power is transferred to the gas molecules. All of those insights aid in an increased understanding of plasma-catalytic ammonia synthesis as a potential green chemistry solution to the synthesis of ammonia on small scale.  
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:188246 Serial 7193
Permanent link to this record
 
 
Author Dingenen, F.; Borah, R.; Ninakanti, R.; Verbruggen, S.W.
Title Probing oxygen activation on plasmonic photocatalysts Type A1 Journal article
Year 2022 Publication Frontiers in Chemistry Abbreviated Journal Front Chem
Volume 10 Issue (up) Pages 988542-10
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In this work we present an assay to probe the oxygen activation rate on plasmonic nanoparticles under visible light. Using a superoxide-specific XTT molecular probe, the oxygen activation rate on bimetallic gold-silver “rainbow” nanoparticles with a broadband visible light (> 420 nm) response, is determined at different light intensities by measuring its conversion into the colored XTT-formazan derivate. A kinetic model is applied to enable a quantitative estimation of the rate constant, and is shown to match almost perfectly with the experimental data. Next, the broadband visible light driven oxygen activation capacity of this plasmonic rainbow system, supported on nano-sized SiO 2 , is demonstrated towards the oxidation of aniline to azobenzene in DMSO. To conclude, a brief theoretical discussion is devoted to the possible mechanisms behind such plasmon-driven reactions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000860818400001 Publication Date 2022-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296-2646 ISBN Additional Links UA library record; WoS full record
Impact Factor 5.5 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5.5
Call Number UA @ admin @ c:irua:190868 Serial 7197
Permanent link to this record
 
 
Author Spanoghe, J.
Title Purple bacteria cultivation on light, carbon dioxide and hydrogen gas : exploring and tuning the potential for microbial food production Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages vi, 207 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The human population is projected to grow to 9.7 billion by 2050, resulting in an estimated increase in protein demand of 50%. From an environmental perspective, the current and future demand of protein cannot be sustainably met as the conventional food production chain is severely altering biogeochemical cycles of nitrogen and phosphorus, biodiversity and land-use, with flows towards the biosphere and oceans that are exceeding the planetary boundaries. Microbial protein (protein derived from microorganisms) has been suggested as an excellent sustainable protein source, a fortiori when produced in a land- and fossil free manner. The photoautohydrogenotrophic cultivation (i.e. with light, CO2 and H2) of purple bacteria links up perfectly with the upcoming green electrification of industry (green H2) and the need for carbon capture and utilization. However, this metabolism represented a gap in literature, and thus this thesis aimed to establish a basic knowledge platform on its kinetic, stoichiometric and nutritional performance. At first, three originally photoheterotrophically enriched purple bacteria were studied of which Rhodobacter capsulatus reached the highest protein productivity of 0.16 g protein/L/d, which aligned well with the commonly-known photoautotrophic microalgae. Moreover, a full dietary essential amino acid match was found for human food, while the fatty acid content was dominated by the health-stimulating vaccenic acid (82-86%). Lastly, the achieved protein yield in photoautohydrogenotrophic purple bacteria was 2.3 times higher compared to hydrogen oxidizing bacteria, indicating a resource-efficient use of H2. Next, a photoautohydrogenotrophic enrichment of wastewater treatment microbiomes was performed in search for specialist species. While the isolates of this enrichment showed improvements in their performance during acclimation, the kinetic and nutritional performance of Rhodobacter capsulatus still excelled. Subsequently, the influence of nutrient limitations (C or N) and nitrogen gas fixation was studied on the nutritional tuning potential. Both the limitations as well as the N2 fixation resulted in the shift of the essential amino acid profiles. Additionally, the limitations significantly decreased the pigment content, while an increase in the storage of poly-P was seen in case of carbon limitations. The next major challenge was the production intensification in a photobioreactor of which the design was linked to minimizing both H2 and light limitations. The chosen bubble-column photobioreactor already resulted in a doubled biomass productivity. Finally, the remaining technological and non-technological challenges ahead for the production of a high-value, cost-efficient, environment-friendly microbial protein that complies with legislative requirements and appeals to future consumers were discussed.
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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 978-90-5728-741-1 Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:188233 Serial 7198
Permanent link to this record
 
 
Author Spanoghe, J.; Ost, K.J.; Van Beeck, W.; Vermeir, P.; Lebeer, S.; Vlaeminck, S.E.
Title Purple bacteria screening for photoautohydrogenotrophic food production : are new H₂-fed isolates faster and nutritionally better than photoheterotrophically obtained reference species? Type A1 Journal article
Year 2022 Publication New biotechnology Abbreviated Journal New Biotechnol
Volume 72 Issue (up) Pages 38-47
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Photoautohydrogenotrophic enrichments of wastewater treatment microbiomes were performed to obtain hypothetically high-potential specialist species for biotechnological applications. From these enrichment cultures, ten photoautohydrogenotrophic species were isolated: six Rhodopseudomonas species, three Rubrivivax members and Rhodobacter blasticus. The performance of these isolates was compared to three commonly studied, and originally photoheterotrophically enriched species (Rhodopseudomonas palustris, Rhodobacter capsulatus and Rhodobacter sphaeroides), designated as reference species. Repeated subcultivations were applied to improve the initial poor performance of the isolates (acclimation effect), which resulted in increases in both maximum growth rate and protein productivity. However, the maximum growth rate of the reference species remained 3–7 times higher compared to the isolates (0.42–0.84 d−1 at 28 °C), while protein productivities remained 1.5–1.7 times higher. This indicated that H2-based enrichment did not result in photoautohydrogenotrophic specialists, suggesting that the reference species are more suitable for intensified biomass and protein production. On the other hand, the isolates were able to provide equally high protein quality profiles as the references species, providing full dietary essential amino acid matches for human food. Lastly, the effect of metabolic carbon/electron switching (back and forth between auto- to heterotrophic conditions) initially boosted µmax when returning to photoautohydrogenotrophic conditions. However, the switch negatively impacted lag phase, protein productivities and pigment contents. In the case of protein productivity, the acquired acclimation was partially lost with decreases of up to 44 % and 40 % respectively for isolates and reference species. Finally, the three reference species, and specifically Rh. capsulatus, remained the most suitable candidate(s) for further biotechnological development.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000861078800005 Publication Date 2022-08-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1871-6784; 1876-4347 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.4 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5.4
Call Number UA @ admin @ c:irua:190188 Serial 7199
Permanent link to this record
 
 
Author Peng, L.; Lou, W.; Xu, Y.; Yu, S.; Liang, C.; Alloul, A.; Song, K.; Vlaeminck, S.E.
Title Regulating light, oxygen and volatile fatty acids to boost the productivity of purple bacteria biomass, protein and co-enzyme Q10 Type A1 Journal article
Year 2022 Publication The science of the total environment Abbreviated Journal Sci Total Environ
Volume 822 Issue (up) Pages 153489
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Purple non‑sulfur bacteria (PNSB) possess significant potential for bioresource recovery from wastewater. Effective operational tools are needed to boost productivity and direct the PNSB biomass towards abundant value-added substances (e.g., protein and co-enzyme Q10, CoQ10). This study aimed to investigate the impact of light, oxygen and volatile fatty acids (VFAs) on PNSB growth (i.e., Rhodobacter sphaeroides) and productivity of protein and CoQ10. Overall, the biomass yields and specific growth rates of PNSB were in the ranges of 0.57–1.08 g biomass g−1 CODremoved and 0.48–0.71 d−1, respectively. VFAs did not influence the biomass yield, yet acetate and VFA mixtures enhanced the specific growth rate with a factor of 1.2–1.5 compared to propionate and butyrate. The most PNSB biomass (1.08 g biomass g−1 CODremoved and 0.71 d−1) and the highest biomass quality (protein content of 609 mg g−1 dry cell weight (DCW) and CoQ10 content of 13.21 mg g−1 DCW) were obtained in the presence of VFA mixtures under natural light and microaerobic (low light alternated with darkness; dissolved oxygen (DO) between 0.5 and 1 mg L−1) conditions (vs. light anaerobic and dark aerobic cultivations). Further investigation on VFAs dynamics revealed that acetate was most rapidly consumed by PNSB in the individual VFA feeding (specific uptake rate of 0.76 g COD g−1 DCW d−1), while acetate as a co-substrate in the mixed VFAs feeding might accelerate the consumption of propionate and butyrate through providing additional cell metabolism precursor. Enzymes activities of succinate dehydrogenase and fructose-1,6-bisphosphatase as well as the concentration of photo pigments confirmed that light, oxygen and VFAs regulated the key enzymes in the energy metabolism and biomass synthesis to boost PNSB growth. These results provide a promising prospect for utilization of fermented waste stream for the harvest of PNSB biomass, protein and CoQ10.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000766801800010 Publication Date 2022-02-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 9.8
Call Number UA @ admin @ c:irua:185706 Serial 7202
Permanent link to this record
 
 
Author Guo, A.; Bai, H.; Liang, Q.; Feng, L.; Su, X.; Van Tendeloo, G.; Wu, J.
Title Resistive switching in Ag₂Te semiconductor modulated by Ag+-ion diffusion and phase transition Type A1 Journal article
Year 2022 Publication Advanced Electronic Materials Abbreviated Journal Adv Electron Mater
Volume Issue (up) Pages 2200850-2200858
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Memristors are considered to be the fourth circuit element and have great potential in areas like logic operations, information storage, and neuromorphic computing. The functional material in a memristor, which has a nonlinear resistance, is the key component to be developed. Herein, resistive switching is demonstrated and the structural evolutions in Ag2Te are examined under an external electric field. It is shown that the electroresistance effect is originating from an electronically triggered phase transition together with directional Ag+-ion diffusion. Using in situ transmission electron microscopy, the phase transition from the monoclinic alpha-Ag2Te into the face-centered cubic beta-Ag2Te, accompanied by a change in resistance, is directly observed. Diffusion of Ag+-ions modulates the localized density of Ag+-ion vacancies, leading to a change in electrical conductivity and influences the threshold voltage to trigger the phase transition. During the electric field-driven phase transition, the spontaneous and localized multiple polarizations from the low-symmetry alpha-Ag2Te (referring to an antiferroelectric structure) are vanishing in the cubic beta-Ag2Te (referring to a paraelectric structure). The abrupt resistance change of thin Ag2Te caused by the phase transition and modulated by the applied electric field demonstrates its great potential as functional material in volatile memory and memristors with a low-energy consumption.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000855728500001 Publication Date 2022-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2199-160x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.2 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 6.2
Call Number UA @ admin @ c:irua:190582 Serial 7203
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Author Van Tendeloo, M.
Title Resource-efficient nitrogen removal from sewage : kinetic, physical and chemical tools for mainstream partial nitritation/anammox Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages iv, 204 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Adequate removal of pollutants from sewage is important to protect the environment and public health. Today, sewage treatment plants are operational in many parts of the world, and although the used technologies are effective in removing pollutants from wastewater, they are energy- and resource-intensive. Reshaping sewage treatment into a two-stage system, with separated organic carbon and nitrogen removal, facilitates the transformation towards energy-positive sewage treatment. This thesis will focus on resource-efficient nitrogen removal from sewage via partial nitritation/anammox (PN/A), with reduced organic carbon and oxygen consumption compared to conventional techniques. PN/A relies on the teamwork between two microbial groups to convert ammonium into nitrogen gas. Several other groups of microbes however can proliferate in the sludge, competing for substrate with the key players, lowering the nitrogen removal efficiency and increasing the energy demand. To obtain the desired microbial community, control tools should be applied to selectively promote the desired microbes while suppressing the unwanted competitors. In this thesis, multiple control tools were studied to establish a workable framework for successful implementation of PN/A in the main stream of a sewage treatment plant. These tools can be divided into three categories: i) kinetic tools, regulating substrate availability (e.g., oxygen availability control and residual ammonium concentration), ii) physical tools, revolving around sludge retention and selection (e.g., sludge age control and sludge aggregation form), and iii) chemical tools, exposing the sludge to stress conditions for which the unwanted microbes are vulnerable (e.g., sludge treatments with a single stressor such as free ammonia). The first research chapter focussed on oxygen availability control and single-stressor sludge treatments. The following two chapters covered the development of a novel multi-stressor concept combining substrate starvation and exposure to sulphide and free ammonia. In the final research chapter, the previously obtained knowledge was combined into a demonstration study on pilot-scale. The combination of these control tools was found effective in achieving nitrogen removal via PN/A, both on lab- and pilot-scale. Consequently, the obtained results in this thesis can catalyse the implementation of mainstream PN/A by providing a toolbox with multiple control tools and clever reactor design, thus advancing the concept of energy neutrality and resource efficiency in sewage treatment plants.
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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:187665 Serial 7204
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Author Allegretta, I.; Legrand, S.; Alfeld, M.; Gattullo, C.E.; Porfido, C.; Spagnuolo, M.; Janssens, K.; Terzano, R.
Title SEM-EDX hyperspectral data analysis for the study of soil aggregates Type A1 Journal article
Year 2022 Publication Geoderma: an international journal of soil science Abbreviated Journal Geoderma
Volume 406 Issue (up) Pages
Keywords A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract Scanning electron microscopy coupled with microanalysis (SEM-EDX) is an important analytical tool for the morphological and chemical characterization of different types of materials. In many applications, SEM-EDX elemental maps are usually used and processed as images, thus flattening and reducing the spectroscopic information contained in EDX hyperspectral data cubes. The exploitation of the full hyperspectral dataset could be indeed very useful for the study of complex matrices like soil. In order to maximize the information attainable by SEM-EDX data cubes analysis, the software package “Datamuncher Gamma” was implemented and applied to study soil aggregates. By using this approach, different phases (silicates, aluminosilicates, Ca-carbonates, Ca-phosphates, organic matter, iron oxides) inside soil aggregates were successfully identified and segmented. The advantages of this method over the common ROI imaging approach are presented. Finally, this method was used to compare different aggregates in a Cr-polluted soil and understand their possible pedological history. The present method can be used for the analysis of every type of SEM-EDX data cubes, allowing its application to different types of samples and fields of study.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000708893700026 Publication Date 2021-10-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0016-7061 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.1 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 6.1
Call Number UA @ admin @ c:irua:182493 Serial 7207
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Author Cui, Z.; Zhou, C.; Jafarzadeh, A.; Meng, S.; Yi, Y.; Wang, Y.; Zhang, X.; Hao, Y.; Li, L.; Bogaerts, A.
Title SF₆ catalytic degradation in a γ-Al₂O₃ packed bed plasma system : a combined experimental and theoretical study Type A1 Journal article
Year 2022 Publication High voltage Abbreviated Journal
Volume Issue (up) Pages 1-11
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Effective abatement of the greenhouse gas sulphur hexafluoride (SF6) waste is of great importance for the environment protection. This work investigates the size effect and the surface properties of gamma-Al2O3 pellets on SF6 degradation in a packed bed dielectric barrier discharge (PB-DBD) system. Experimental results show that decreasing the packing size improves the filamentary discharges and promotes the ignition and the maintenance of plasma, enhancing the degradation performance at low input powers. However, too small packing pellets decrease the gas residence time and reduce the degradation efficiency, especially for the input power beyond 80 W. Besides, lowering the packing size promotes the generation of SO2, while reduces the yields of S-O-F products, corresponding to a better degradation. After the discharge, the pellet surface becomes smoother with the appearance of S and F elements. Density functional theory calculations show that SF6 is likely to be adsorbed at the Al-III site over the gamma-Al2O3(110) surface, and it is much more easily to decompose than in the gas phase. The fluorine gaseous products can decompose and stably adsorb on the pellet surface to change the surface element composition. This work provides a better understanding of SF6 degradation in a PB-DBD system.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000827312700001 Publication Date 2022-07-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-7264 ISBN Additional Links UA library record; WoS full record
Impact Factor 4.4 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.4
Call Number UA @ admin @ c:irua:189603 Serial 7208
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Author Van Putte, N.; Meire, P.; Seuntjens, P.; Joris, I.; Verreydt, G.; Hambsch, L.; Temmerman, S.
Title Solving hindered groundwater dynamics in restored tidal marshes by creek excavation and soil amendments : a model study Type A1 Journal article
Year 2022 Publication Ecological engineering: the journal of ecotechnology Abbreviated Journal Ecol Eng
Volume 178 Issue (up) Pages 106583-15
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL); Ecosphere
Abstract Groundwater fluxes in tidal marshes largely control key ecosystem functions and services, such as vegetation growth, soil carbon sequestration, and nutrient cycling. In tidal marshes restored on formerly embanked agricultural land, groundwater fluxes are often limited as compared to nearby natural marshes, as a result of historical agricultural soil compaction. To improve the functioning of restored tidal marshes, knowledge is needed on how much certain design options can optimize soil-groundwater interactions in future restoration projects. Based on measured data on soil properties and tidally induced groundwater dynamics, we calibrated and evaluated a 2D vertical model of a creek-marsh cross-section, accounting for both saturated and unsaturated groundwater flow and solute transport in a variably saturated groundwater flow model. We found that model simulations of common restoration practices such as soil amendments (increasing the depth of porous soil on top of the compact layer) and creek excavation (increasing the creek density) increase the soil aeration depth and time, the drainage depth and the solute flux, and decrease the residence time of solutes in the porewater. Our simulations indicate that increasing the depth to the compact layer from 20 cm to 40 cm, or increasing the creek density from 1 creek to 2 creeks along a 50 m marsh transect (while maintaining the total creek cross-sectional area), in both cases more than doubles the volume of water processed by the marsh soil. We discuss that this may stimulate nutrient cycling. As such, our study demonstrates that groundwater modelling can support the design of marsh restoration measures aiming to optimize groundwater fluxes and related ecosystem services.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000795478200005 Publication Date 2022-03-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-8574 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.8
Call Number UA @ admin @ c:irua:186605 Serial 7210
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Author Spacova, I.; Ahannach, S.; Breynaert, A.; Erreygers, I.; Wittouck, S.; Bron, P.A.; Van Beeck, W.; Eilers, T.; Alloul, A.; Blansaer, N.; Vlaeminck, S.E.; Hermans, N.; Lebeer, S.
Title Spontaneous riboflavin-overproducing Limosilactobacillus reuteri for biofortification of fermented foods Type A1 Journal article
Year 2022 Publication Frontiers in Nutrition Abbreviated Journal
Volume 9 Issue (up) Pages 916607-916619
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Riboflavin-producing lactic acid bacteria represent a promising and cost-effective strategy for food biofortification, but production levels are typically insufficient to support daily human requirements. In this study, we describe the novel human isolate Limosilactobacillus reuteri AMBV339 as a strong food biofortification candidate. This strain shows a high natural riboflavin (vitamin B2) overproduction of 18.36 mu g/ml, biomass production up to 6 x 10(10) colony-forming units/ml (in the typical range of model lactobacilli), and pH-lowering capacities to a pH as low as 4.03 in common plant-based (coconut, soy, and oat) and cow milk beverages when cultured up to 72 h at 37 degrees C. These properties were especially pronounced in coconut beverage and butter milk fermentations, and were sustained in co-culture with the model starter Streptococcus thermophilus. Furthermore, L. reuteri AMBV339 grown in laboratory media or in a coconut beverage survived in gastric juice and in a simulated gastrointestinal dialysis model with colon phase (GIDM-colon system) inoculated with fecal material from a healthy volunteer. Passive transport of L. reuteri AMBV339-produced riboflavin occurred in the small intestinal and colon stage of the GIDM system, and active transport via intestinal epithelial Caco-2 monolayers was also demonstrated. L. reuteri AMBV339 did not cause fecal microbiome perturbations in the GIDM-colon system and inhibited enteric bacterial pathogens in vitro. Taken together, our data suggests that L. reuteri AMBV339 represents a promising candidate to provide riboflavin fortification of plant-based and dairy foods, and has a high application potential in the human gastrointestinal tract.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000814856600001 Publication Date 2022-06-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296-861x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5
Call Number UA @ admin @ c:irua:189011 Serial 7211
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Author Zhu, W.; Van Tendeloo, M.; Alloul, A.; Vlaeminck, S.E.
Title Towards mainstream partial nitritation/anammox in four seasons : feasibility of bioaugmentation with stored summer sludge for winter anammox assistance Type A1 Journal article
Year 2022 Publication Bioresource technology Abbreviated Journal Bioresource Technol
Volume 347 Issue (up) Pages 126619-11
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The strong effect of low temperatures on anammox challenges its mainstream application over the winter in temperate climates. Winter bioaugmentation with stored summer surplus sludge is a potential solution to guarantee sufficient nitrogen removal in winter. Firstly, the systems for which nitrogen removal deteriorated by the temperature decrease (25 °C → 20 °C) could be fully restored bioaugmenting with granules resp. flocs stored for 6 months at 118 resp. 220% of the initial biomass levels. Secondly, the reactivation of these stored sludges was tested in lower temperature systems (15.3 ± 0.4/10.4 ± 0.4 °C). Compared to the activity before storage, between 56% and 41% of the activity of granules was restored within one month, and 41%–32% for flocs. Additionally, 85–87% of granules and 50–53% of flocs were retained in the systems. After reactivation (15.3 ± 0.4/10.4 ± 0.4 °C), a more specialized community was formed (diversity decreased) with Candidatus Brocadia still dominant in terms of relative abundance. Capital and operating expenditures (CAPEX, OPEX) were negligible, representing only 0.19–0.36% of sewage treatment costs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000781730900001 Publication Date 2021-12-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.4 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 11.4
Call Number UA @ admin @ c:irua:185210 Serial 7220
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Author Pacquets, L.
Title Towards stable Cu-Ag bimetallic nanoparticles to boost the electrocatalytic CO2 reduction Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages xvi, 188 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Ever since the industrial revolution, the emission of greenhouse gasses dramatically increased, resulting in high CO2 concentration in the atmosphere. The electrochemical conversion of CO2 to value added products, such as carbon monoxide, formic acid, methane, ethylene and ethanol is a very promising strategy to inhibit CO2 emissions. Nevertheless, at the moment, the electrochemical CO2 reduction (eCO2R) is not yet industrially viable, mainly due to the lack of good electrocatalysts. On the other hand, core-shell nanoparticles (NPs) have emerged over the last couple of years as promising candidates. It is believed that bimetallic enhancement effects are behind the improved performance of these core-shell NPs when compared to the individual metals. Although widely investigated, there are still some remaining issues and/or open questions. Indeed, the development of a robust and straightforward synthesis method along with fundamental insight into their resistance towards electrochemical stress remains absent. A good control over morphology, size and composition is key in determining which properties are beneficial for the eCO2R. Since these catalysts are designed to be implemented in electrolyzers, they have to maintain long-term performance. This makes the design of a reproducible method, unveiling structure-performance relationships the effect of electrochemical stress, a crucial aspect. Exploring and modifying existing synthesis methods, have led to the acquisition of a robust and reproducible synthesis method where thermal decomposition of the Cu core is combined with the galvanic replacement of Ag in organic solvents. The implementation of this method has led to the design of a wide variety of Cu-Ag bimetallic NPs and enabled to investigate their composition-selectivity profile. Introducing Ag on Cu suppressed hydrogen and increased the CO formation. CO production was boosted by using Cu@Ag core-shells and was promoted even more by changing the type of electrolyte. As these nanoparticles suffered from degradation, the 3D mapping of the structural changes of Cu@Ag core-shells under operating conditions led to the hypothesis of a two-step degradation mechanism where initially Cu leaching was observed with the subsequent sintering of the Ag shells. One approach to avoid this electrochemical degradation, investigated in this research, was the application of an ultrathin carbon layer to protect the active layer. This ultrathin carbon layer operated as a protective layer, suppressing hydrogen production and increasing the stability of the electrocatalyst. In conclusion, the product selectivity can be tuned by using different Cu-Ag bimetallic nanoparticles synthesized through a robust method. Their unique degradation pathway of Cu@Ag core-shell nanoparticles has led to the proposition of a more accurate stabilization strategy. These findings can contribute significantly in the quest for improved electrocatalysts for the eCO2R.
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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:190236 Serial 7221
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Author Gielis, J.; Shi, P.; Caratelli, D.
Title Universal equations : a fresh perspective Type A1 Journal article
Year 2022 Publication Growth and Form Abbreviated Journal
Volume Issue (up) Pages
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract A uniform description of natural shapes and phenomena is an important goal in science. Such description should check some basic principles, related to 1) the complexity of the model, 2) how well its fits real objects, phenomena and data, and 3) ia direct connection with optimization principles and the calculus of variations. In this article, we present nine principles, three for each group, and we compare some models with a claim to universality. It is also shown that Gielis Transformations and power laws have a common origin in conic sections
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:189317 Serial 7224
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Author Magalhães Cunha, S.
Title Wave-packet dynamics and electronic transport properties in 2D materials Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages 219 p.
Keywords Doctoral thesis; Condensed Matter Theory (CMT)
Abstract This piece of work is twofold. First, the time evolution of wave-packets in 2D systems is analyzed by the Split-Operator technique in three different scenarios: in multilayer phosphorene, the transient oscillations in the time-dependent average of position and momentum were observed due to the zitterbewegung effect, and the wave packet propagates non-uniformly along the space deforming itself into an elliptical shape. These results were corroborated by the Green’s function formalism except for large values of the wave-vector and long times; in 2D semiconductor quantum wires (QWs) with anisotropic effective masses and different angle orientations with respect to the anisotropic axis. We have shown that the greater this angle, the smaller is the energy levels spacing implying in an increase of the accessible electronic states. Additionally, for non-null magnetic field, the quantum Hall edge states are significantly affected by the edge orientation. In the anisotropic case damped oscillations in the average values of velocity in both x and y directions where obtained. Theses oscillations are originated by the QW geometry but also from subwavepackets with different momentum orientations, whereas for isotropic QWs the wavepacket disperses without splitting; in the third scenario the split-operator technique was used to study the Landau levels, the wave packet trajectories and velocities of electrons in graphene at low-energy regime described by a modified Dirac equation where the momentum-operator is written in a generalized form as result of applying the position-dependent translation operator formalism (PDTO). In the second part of this thesis, the electronic and tunneling properties of α − T3 lattices were studied. Electrons in these lattices behave analogous to integer-spin Dirac Fermions. The presence of a third atomic site in the unit cell leads to a flat band in the energy spectrum, providing unique electronic and tunneling properties. The presence of a super-periodic potential and the inclusion of symmetry-breaking terms results in deviations of the atomic equivalence between the atomic sites affecting the Dirac points and the band-gap. Small deviations in the equivalence between the atomic sites and the number of barriers change the transmission properties in these lattices. Additionally, new tunneling regions are possible by adjusting the symmetry between the atomic sites and affect the omnidirectional total transmission called super-Klein tunneling observed in these lattices. We compare those results to the tunneling probabilities through regions where the energy spectrum changes from linear with a middle flat band to a hyperbolic dispersion.
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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:189191 Serial 7227
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Author Kovács, A.; Yusupov, M.; Cornet, I.; Billen, P.; Neyts, E.C.
Title Effect of natural deep eutectic solvents of non-eutectic compositions on enzyme stability Type A1 Journal article
Year 2022 Publication Journal Of Molecular Liquids Abbreviated Journal J Mol Liq
Volume 366 Issue (up) Pages 120180-17
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Biochemical Wastewater Valorization & Engineering (BioWaVE); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS)
Abstract Natural deep eutectic solvents (NADES) represent a green alternative to common organic solvents in the biochemical industry due to their benign behavior and tailorable properties, in particular as media for enzymatic reactions. However, to fully exploit their potential in enzymatic reactions, there is a need for a more fundamental understanding of how these neoteric solvents influence the course of these reac-tions. Thus, the aim of this study is to investigate the influence of NADES with various molar composi-tions on the stability and structure of enzymes, applying molecular dynamics simulations. This can help to better understand the effect of individual compounds of NADES, in addition to eutectic mixtures. More specifically, we simulate the behavior of Candida antarctica lipase B (CALB) enzyme in NADES com-posed of choline chloride with either urea, ethylene glycol or glycerol. Hereto, we monitor the NADES microstructure, the general stability of the enzyme and changes in the structure of its active sites and sur-face residues. Our simulations show that none of the studied NADES systems significantly disrupt the microstructure of the solvent or the stability of the CALB enzyme within the time scales of the simula-tions. The enzyme preserves its initial structure, size and intra-chain hydrogen bonds in all investigated compositions and, for the first time reported, also in NADES with increased hydrogen bond donating com-pound ratios. As the main novelty, our results indicate that, in addition to the composition, the molar ratio can be an additional variable to fine-tune the physicochemical properties of NADES without altering the enzyme characteristics. These findings could facilitate the development and application of task -tailored NADES media for biocatalytic processes. (c) 2022 Elsevier B.V. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000865431800010 Publication Date 2022-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0167-7322 ISBN Additional Links UA library record; WoS full record
Impact Factor 6 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 6
Call Number UA @ admin @ c:irua:191538 Serial 7265
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Author Lu, X.P.; Bruggeman, P.J.; Reuter, S.; Naidis, G.; Bogaerts, A.; Laroussi, M.; Keidar, M.; Robert, E.; Pouvesle, J.-M.; Liu, D.W.; Ostrikov, K.(K.)
Title Grand challenges in low temperature plasmas Type A1 Journal article
Year 2022 Publication Frontiers in physics Abbreviated Journal
Volume 10 Issue (up) Pages 1040658-12
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Low temperature plasmas (LTPs) enable to create a highly reactive environment at near ambient temperatures due to the energetic electrons with typical kinetic energies in the range of 1 to 10 eV (1 eV = 11600K), which are being used in applications ranging from plasma etching of electronic chips and additive manufacturing to plasma-assisted combustion. LTPs are at the core of many advanced technologies. Without LTPs, many of the conveniences of modern society would simply not exist. New applications of LTPs are continuously being proposed. Researchers are facing many grand challenges before these new applications can be translated to practice. In this paper, we will discuss the challenges being faced in the field of LTPs, in particular for atmospheric pressure plasmas, with a focus on health, energy and sustainability.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000878212000001 Publication Date 2022-10-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296-424x ISBN Additional Links UA library record; WoS full record
Impact Factor 3.1 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.1
Call Number UA @ admin @ c:irua:192173 Serial 7267
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Author Deben, C.; Cardenas De La Hoz, E.; Le Compte, M.; Van Schil, P.; Hendriks, J.M.H.; Lauwers, P.; Yogeswaran, S.K.; Lardon, F.; Pauwels, P.; van Laere, S.; Bogaerts, A.; Smits, E.; Vanlanduit, S.; Lin, A.
Title OrBITS : label-free and time-lapse monitoring of patient derived organoids for advanced drug screening Type A1 Journal article
Year 2022 Publication Cellular Oncology (2211-3428) Abbreviated Journal Cell Oncol
Volume Issue (up) Pages 1-16
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Center for Oncological Research (CORE)
Abstract Background Patient-derived organoids are invaluable for fundamental and translational cancer research and holds great promise for personalized medicine. However, the shortage of available analysis methods, which are often single-time point, severely impede the potential and routine use of organoids for basic research, clinical practise, and pharmaceutical and industrial applications. Methods Here, we developed a high-throughput compatible and automated live-cell image analysis software that allows for kinetic monitoring of organoids, named Organoid Brightfield Identification-based Therapy Screening (OrBITS), by combining computer vision with a convolutional network machine learning approach. The OrBITS deep learning analysis approach was validated against current standard assays for kinetic imaging and automated analysis of organoids. A drug screen of standard-of-care lung and pancreatic cancer treatments was also performed with the OrBITS platform and compared to the gold standard, CellTiter-Glo 3D assay. Finally, the optimal parameters and drug response metrics were identified to improve patient stratification. Results OrBITS allowed for the detection and tracking of organoids in routine extracellular matrix domes, advanced Gri3D (R)-96 well plates, and high-throughput 384-well microplates, solely based on brightfield imaging. The obtained organoid Count, Mean Area, and Total Area had a strong correlation with the nuclear staining, Hoechst, following pairwise comparison over a broad range of sizes. By incorporating a fluorescent cell death marker, infra-well normalization for organoid death could be achieved, which was tested with a 10-point titration of cisplatin and validated against the current gold standard ATP-assay, CellTiter-Glo 3D. Using this approach with OrBITS, screening of chemotherapeutics and targeted therapies revealed further insight into the mechanistic action of the drugs, a feature not achievable with the CellTiter-Glo 3D assay. Finally, we advise the use of the growth rate-based normalised drug response metric to improve accuracy and consistency of organoid drug response quantification. Conclusion Our findings validate that OrBITS, as a scalable, automated live-cell image analysis software, would facilitate the use of patient-derived organoids for drug development and therapy screening. The developed wet-lab workflow and software also has broad application potential, from providing a launching point for further brightfield-based assay development to be used for fundamental research, to guiding clinical decisions for personalized medicine.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000898426100001 Publication Date 2022-12-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2211-3428; 2211-3436 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.6 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 6.6
Call Number UA @ admin @ c:irua:192698 Serial 7272
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Author Wang, J.
Title Plasma catalysis : study of CO2 reforming of CH4 in a DBD reactor Type Doctoral thesis
Year 2022 Publication Abbreviated Journal
Volume Issue (up) Pages XVI, 232 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The plasma-based dry reforming in a dielectric barrier discharge (DBD) reactor is important to achieve sustainable goals, but many challenges remain. For example, the conversion and energy yield of DBD reactors are relatively low, and the catalysts or packing materials used in existing studies cannot improve them, possibly due to the unsuitable properties and structures of catalysts or packing materials for plasma processes. In order to study the effect of catalyst structure on plasma-based dry reforming, a controllable synthesis of the catalyst supports or templates was explored. In Chapter 2, an initially immiscible synthesis method was proposed to synthesize uniform silica spheres, which can replace the organic solvent-based Stöber method to successfully synthesize silica particles with the same size ranges as the original Stöber process without addition of organic solvents. Using the silica spheres as templates, 3D porous Cu and CuO catalysts with different pore sizes were synthesized in Chapter 3 to study the effect of catalyst pore size on the plasma-catalytic dry reforming. In most cases, the smaller the pore size, the higher the conversion of CH4 and CO2 due to the reaction of radicals and ions formed in the plasma. An exception are the samples synthesized from 1 μm silica, which show better performance due to the electric field enhancement for pore sizes close to the Debye length. Besides the pore size, the particle diameter of the catalyst or packing is also one of the important factors affecting the interaction between plasma and catalyst. In Chapter 4, SiO2 spheres (with or without supported metal) were used to study the effect of different support particle sizes on plasma-based dry reforming. We found that a uniform SiO2 packing improves the conversion of plasma-based dry reforming. The conversion of plasma-based dry reforming first increases and then decreases with increasing particle size, due to the balance between the promoting and hindering effect of the particle filling on the plasma discharge. Chapter 5 is to improve the design of the DBD reactor itself, in order to try to increase its low energy yield. Some stainless steel rings were put over the inner electrode rod of the DBD reactor. The presence of rings increases the local electric field, the displaced charges and the discharge fraction, and also makes the discharge more stable and with more uniform intensity. The placement of the rings improves the performance of the reactor at 30 W supplied power.
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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:194045 Serial 7273
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Author Bignoli, F.; Rashid, S.; Rossi, E.; Jaddi, S.; Djemia, P.; Terraneo, G.; Li Bassi, A.; Idrissi, H.; Pardoen, T.; Sebastiani, M.; Ghidelli, M.
Title Effect of annealing on mechanical properties and thermal stability of ZrCu/O nanocomposite amorphous films synthetized by pulsed laser deposition Type A1 Journal article
Year 2022 Publication Materials & design Abbreviated Journal Mater Design
Volume 221 Issue (up) Pages 110972-10
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Binary ZrCu nanocomposite amorphous films are synthetized by pulsed laser deposition (PLD) under vac-uum (2 x 10-3 Pa) and 10 Pa He pressure, leading to fully amorphous compact and nanogranular mor-phologies, respectively. Then, post-thermal annealing treatments are carried out to explore thermal stability and crystallization phenomena together with the evolution of mechanical properties. Compact films exhibit larger thermal stability with partial crystallization phenomena starting at 420 degrees C, still to be completed at 550 degrees C, while nanogranular films exhibit early-stage crystallization at 300 degrees C and com-pleted at 485 degrees C. The microstructural differences are related to a distinct evolution of mechanical
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000886072100004 Publication Date 2022-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0264-1275; 1873-4197 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.4 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 8.4
Call Number UA @ admin @ c:irua:192194 Serial 7299
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Author Hajizadeh, A.; Shahalizade, T.; Riahifar, R.; Yaghmaee, M.S.; Raissi, B.; Gholam, S.; Aghaei, A.; Rahimisheikh, S.; Ghazvini, A.S.
Title Electrophoretic deposition as a fabrication method for Li-ion battery electrodes and separators : a review Type A1 Journal article
Year 2022 Publication Journal of power sources Abbreviated Journal J Power Sources
Volume 535 Issue (up) Pages 231448-26
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Electrophoretic Deposition (EPD) is one of the alternative methods to fabricate and enhance the performance of Li-ion batteries. It enables the fabrication of electrodes with outstanding qualities and different electrochemical properties by the great domination over various parameters. EPD facilitates the processing of electrodes by binder-free grafting of nanomaterials, such as graphene derivatives, carbon nanotube, and nanoparticles, into the battery electrodes. It also enables the assembly of the free-standing electrodes with 3D structure and provides possibilities, such as the fabrication of the electrodes with an oriented microstructure, even on 3D substrates to improve the energy or power density. In this review, after an introduction to EPD, the effect of EPD parameters on the properties of the prepared electrodes is reviewed. Then, EPD is compared with tape cast, and its advantages over the conventional method are evaluated. Also, employing the EPD method as an intermediate process is discussed. Finally, the application of EPD in the fabrication of separators is assessed, and the prospects for the future are described.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000913348500001 Publication Date 2022-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0378-7753 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.2 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 9.2
Call Number UA @ admin @ c:irua:194403 Serial 7303
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