toggle visibility
Search within Results:
Display Options:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author De Weerdt, L. file  openurl
  Title An inquiry into the market acceptance of circular plastics Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages xii, 154 p.  
  Keywords Doctoral thesis; Engineering Management (ENM)  
  Abstract Closing material loops and reducing resource extraction is considered to be the foundation of the circular economy that delivers environmental gains. Today, certain materials with large environmental impacts, such as plastics, are placed high on the circularity agenda. In this thesis, the market acceptance of circular plastics is analyzed. Firstly, the current – mostly linear – market for plastics in the European Union is analyzed. We find that market failure and uncertainties lead to postponed and scaled down private investments in recycling facilities for plastics. As a consequence, we conclude the failing and uncertain market needs government intervention. Secondly, potential government interventions that alleviate the market failure and reduce the present uncertainties are analyzed. Government intervention can be either incentive-based or regulatory-based. The Flemish government already acts as an incentivizer. For more than two decades already, a tax is levied on the incineration of plastic waste. We find that this tax reduces industrial plastic waste generation, but fails to elicit investments in recycling facilities. Regulatory-based policies are expected to gain in importance in the pursuit of a circular economy. Indeed, in the European Commission’s latest circularity action plan, a policy to mandate the use of recycled plastics is signaled. Mandating the use of recycled plastics can enable the circularity of plastics effectively. However, it would also generate a shock wave on the market, especially because, i.a. the implementation time of such a policy is uncertain. We investigate how firms can invest optimally in the use of recycled plastics under the presence of policy uncertainty. We conclude that the European market will be able to successfully adopt circular plastics. However, stimulating policies, both incentive-based and regulatory-based, turn out to be essential in this adoption process. Therefore, there will be a need for a combination of policies in order to prevent the incessant mass single-use consumption of plastics, which harms the environment.  
  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:178913 Serial 6930  
Permanent link to this record
 

 
Author Einhäupl, P. openurl 
  Title Landfill mining : implementing the missing link to a circular economy: an evaluation of the societal sustainability Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages xxiii, 216 p.  
  Keywords Doctoral thesis; Economics; Engineering sciences. Technology; Engineering Management (ENM)  
  Abstract One of the main objectives of implementing a circular economy system is the reuse and recycling of resources. Closing material cycles and renewable-based electricity and fuel production are essential to such systems. To achieve a high degree of circularity, waste streams have to be rethought and integrated from a cradle-to-grave to a cradle-to-cradle approach. However, today’s circular economy strategies mostly focus on current waste streams, while past waste streams, buried in landfills, could play an important role when recovering resources and energy. Hence, a well-thought-out circular economy strategy should include the re-integration of past waste streams. A grave-to-cradle approach is needed. Landfill mining (LFM), i.e. the excavation and processing of formerly buried waste to energy and materials, aims at utilizing these past waste streams. Doing so could bear potential economic, environmental, and societal burdens and benefits. Originating from landfill remediation projects, landfill mining has been further developed towards resource recovery. Today, using up-to-date technologies and following the most stringent environmental and social criteria, the concept is also known as enhanced landfill mining (ELFM). Throughout the relevant scientific literature, most attention is given to advances in technological development for (E)LFM, as well as its techno-economic and environmental assessment. Societal assessments of LFM projects are rare and treat societal impacts only selectively or from unilateral societal perspectives. If stakeholders are included in societal (E)LFM assessments, only industrial actors, like landfill operators, and governmental actors are asked to participate. A holistic stakeholder assessment for (E)LFM is missing. Moreover, the diverse societal impacts – ranging from socio-environmental benefits through the mitigation of health risks, over socio-economic benefits through land reclamation, and social benefits through community engagement, for example – are either only studied selectively or evaluated as one, entangling various societal effects. A holistic and specific assessment of societal factors affecting (E)LFM implementation is also missing. This thesis uses an anticipatory approach to tackle these challenges. This approach aims to integrate stakeholder values and include uncertainty through the use of multiple social perspectives and prospective modeling tools. In-depth interviews were conducted to develop a typology of (E)LFM stakeholders and to elicit the most important stakeholder needs. Stakeholders were selected along an extended quadruple helix framework, including industrial, institutional, scientific, and community actors. Furthermore, using system dynamics tools, namely causal loop diagrams, societal systems of (E)LFM could be visualized and analyzed. Finally, a discrete choice experiment was conducted to evaluate a set of societal factors representing the conversion of a landfill into a public park for recreational use. The in-depth interviews included landfill operators, technology providers and incubators, local governments and governmental institutions, as well as researchers and community members. To structure the diverse perspectives of stakeholders on (E)LFM, five stakeholder archetypes were developed: The Entrepreneur, the Engaged Citizen, the Visionary, the Technology Enthusiast, and the Skeptic. The archetypes capture important characteristics and opinions approaching (E)LFM implementation. They differ in risk perceptions, knowledge base, influence on (E)LFM’s systemic and project implementation, and their main concerns and motivations. Furthermore, 18 stakeholder needs were derived from the interviews. This includes societal, environmental, regulatory, and techno-economic needs. The needs are put in relation to the affected stakeholders and sustainability dimensions. Uncertainties that could potentially be reduced through the fulfillment of each need are qualitatively assessed. Quantitatively, stakeholders were focusing on societal, regulatory, and techno-economic needs, whereas qualitative emphasis was given to environmental needs, especially the avoidance of impacts from primary resource production. When meeting stakeholder needs fairly, intra- and inter-dimensional trade-offs have to be considered as different perspectives can lead to different and sometimes contradicting implications for (E)LFM implementation. To conceptualize societal systems of (E)LFM, causal loop diagrams were developed following system dynamics methodology. The visualizations show how (E)LFM is embedded in its societal context. Variables comprising the societal impact were analyzed, and mechanisms affecting the public project acceptance and the market acceptance of (E)LFM products worked out. Leverage points were identified, helping (E)LFM practitioners and policymakers to minimize potential risks and maximize potential benefits. To these count technological choices, stakeholder involvement, the after-use, quality standards, and LFM regulation in general, amongst others. To disentangle and evaluate societal impacts of (E)LFM, a discrete choice experiment was conducted deriving the utility of five distinct attributes: the size of a landfill, the project duration, job creation, disamenities, and climate impacts. To determine the willingness to pay, perform scenario analysis, and model policy simulations, a sixth attribute was added representing a cost factor for project implementation. Environmental considerations are most important to the sample, while project duration and disamenities also play a significant role. The scenario analysis and policy simulations show that taxing households for (E)LFM implementation is a viable option, especially for environmentally beneficial projects. Nonetheless, a favorable combination of the remaining attributes can compensate utility losses for environmentally questionable projects. As risks of classical landfill management practices are likely to grow with an updated evaluation of after-care periods lasting up to 100 years and more, positive effects of (E)LFM become even more noteworthy. Nonetheless, (E)LFM projects also pose potential risks like groundwater contamination or the reintroduction of hazardous materials. If executed poorly, (E)LFM projects could potentially do more harm than good. A mix of policy measures is recommended to push a major part of potential (E)LFM projects from being environmentally beneficial and economically inefficient to being societally, environmentally, and economically favorable. Overall, more research is necessary to integrate (E)LFM into circular economy strategies and build a sensible grave-to-cradle approach.  
  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:181007 Serial 6935  
Permanent link to this record
 

 
Author Admasu, W.F. openurl 
  Title Socioeconomic and environmental impact of expropriation of agricultural land for urbanisation in Ethiopia Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 162 p.  
  Keywords Doctoral thesis; Engineering Management (ENM)  
  Abstract Globally, incorporation of agricultural lands into the urban boundary has been a common phenomenon. Governments use various alternatives to access the required land, including land expropriation procedures, which refers to the compulsorily taking of land from the landholders without their consent by paying compensation. In Ethiopia, the urban population is growing rapidly which resulted into an increase in the demand for urban land for housing construction, public services provision, and infrastructure developments. As the Ethiopian constitution prohibits sale of landholders, governments, at various levels, have been expropriating land from the surrounding farmers to meet the demand for urban land. The general objective of this thesis is to improve the understanding of the impacts of local land deals for urbanization on socioeconomics of farmers and the environment. The findings of this thesis revealed that there are gaps in the current practices of land expropriation for urban expansion that should be improved. The results showed that the compensation paid to the affected farmers is found to be economically inappropriate, i.e., not enough to restore the affected farmers’ livelihoods, in contrast with the land laws that allows a compensation amount that would put previous land users in a better or the same wellbeing as before the land expropriation. In addition, it is indicated that the land expropriation process does not take into account the value of ecosystem services, which are benefits obtain from the land, and important for the wellbeing of the society. We conclude that while land expropriation is an important tool to obtain land from the landholders when it is needed for public purposes, the practices in the study area show it is adversely affecting the socioeconomics of farmers and the environment.  
  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:177909 Serial 6944  
Permanent link to this record
 

 
Author Bjørnåvold, A. isbn  openurl
  Title Unlocking lock-in : accelerating socio-technical transitions to sustainability Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 189 p.  
  Keywords Doctoral thesis; Linguistics; Engineering Management (ENM)  
  Abstract Achieving global sustainability goals will require cleaner and cheaper technologies. Public policy is central to achieving these goals and, in turn, ensuring a quicker pace of change. A major obstacle lies in the fact that technologies cannot be considered isolated entities: they are embedded in a powerful social context of cultural, organisational and institutional systems. This intertwining of different elements is referred to as a socio-technical system. This thesis discusses how socio-technical systems have, over time, allowed locked-in configurations to emerge, referring to a combination of systematic forces that perpetuate unsustainable infrastructures embedded in society. Such lock-ins can inhibit innovation and competitiveness of low-carbon and sustainable technologies, and this thesis looks to concrete solutions for unlocking them. Vital to this objective lies better understanding preferences, intentions, and behaviour of actors involved at each stage of technological development to improve public policy design. A discrete choice experiment – a quantitative non-market valuation method – was, therefore, a core method used to model preferences of key target groups. Target groups considered in the four components of the thesis include i) industry players, ii) policymakers, iii) farmers, and iv) the general public in Belgium, France, Germany, Italy and Spain. The thesis seeks to establish how both economic and regulatory instruments can be leveraged to overcome lock-in. One conclusion sees that implementing an efficient environmental tax regime – an economic instrument – requires balancing political feasibility and public acceptance considerations in line with tax and environmental policy. Results indicate that public acceptance for environmental taxation increases with earmarking. Another conclusion highlights the importance of taking behavioural and habitual considerations into account – both when considering policymakers’ investment decisions, and farmers’ decisions to adopting agro-ecological practices when responding to regulatory instruments. Overall, policy design should emphasise a more continuous and systemic approach to innovation and technology policy on the road to accelerating socio-technical transitions to sustainability.  
  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 978-90-5728-692-6 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:179247 Serial 6949  
Permanent link to this record
 

 
Author Sabzalipour, A. url  openurl
  Title Charge transport in magnetic topological insulators Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages xiv, 185 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract Novel quantum phases of matter and developing practical control over their characteristics is one of the primary aims of current condensed matter physics. It offers the potential for a new generation of energy, electronic and photonic technologies. Among all the newly found phases of matter, topological insulators are novel phases of quantum matter with fascinating bulk band topology and surface states protected by specific symmetries. For example, at the boundary of a strong topological insulator and a trivial insulator, metallic surface states appear that are protected by time-reversal symmetry. As a result, the bulk continues to be insulating, while the surface can support exotic high-mobility spin-polarized electronic states. Since there is no such thing as a clean system, impurities and other disorders are always present in materials. Even while impurities appear to be unfavorable to a system at first look, doping the host system with impurities allows us to engineer different electronic properties of systems, such as the Fermi level or electron density. Because of the symmetry protected metallic states in topological insulators, charge transport responds distinctively to magnetic and non-magnetic impurities. This doctoral dissertation explores how the longitudinal charge transport in magnetic topological thin films and the anomalous Hall effect on the surface of 3D magnetic topological insulators is influenced by point-like and randomly distributed dilute magnetic impurities. We are interested in how charge transport in these systems responds to the orientation of the magnetization orientation and how this response evolves based on the system's main characteristics, such as the magnitude of the Fermi level or gate voltage. Because topological insulators have a strong spin-orbit coupling, the interaction between conducting electrons and local magnetic impurities is very anisotropic. We will show that this anisotropy even enhances when magnetic topological thin films are exposed to a substrate or gate voltage. Therefore, to properly capture this anisotropy in charge transport calculations, we rely on a generalized Boltzmann formalism together with a modified relaxation time scheme. We show that magnetic impurities affect the charge transport in topological insulators by inducing a transition selection rule that governs scatterings of electrons between various electronic states. We see that this selection rule is highly sensitive to the spin direction of the magnetic impurities as well as the position of the Fermi level. According to this selection rule and depending on the position of the Fermi level, two different transport regimes are realized in magnetic topological thin films. In one of these regimes, our findings show that a dissipation less charge current can be generated. In other words, even if there are many magnetic impurities in the system, electrons do not notice them and, remarkably, conduct charge without dissipation. Outside this regime, the charge transport is always dissipative and its sensitivity to the spatial orientation of the magnetic impurities can be effectively modulated by a substrate or gate voltage. In this doctoral thesis, we also explore the anomalous Hall effect (AHE) on the surface of 3D magnetic topological insulators. The AHE is generated by three mechanisms: the intrinsic effect (owing to a nonzero Berry curvature), the side jump effect, and the skew scattering effect. They compete to dominate the AHE in distinct regimes. Analytically, we calculate the contributions of all three mechanisms to the scattering of massive Dirac fermions by magnetic impurities. Our results reveal three transport regimes based on the relative importance of the engaged mechanisms. The identification of these three distinctive transport regimes can assist experimentalists in achieving a regime in which each contribution is dominant over the others, allowing them to measure them separately. Typically, this is not feasible empirically since the total value of the experimentally observed AHE conceals the specific information of each of the three contributions. Based on our analytical calculations, we prove that the AHE can change sign by varying the orientation of the surface magnetization, the concentration of impurities, and the location of the Fermi level, which is consistent with previous experimental findings. In addition, we show that by suitably adjusting the given parameters, any contribution to the AHE, or even the entire AHE, can be turned off. For example, in a system with in-plane magnetization, one can turn off the AHE by pushing the system into the completely metallic regime. Furthermore, we demonstrate that any contribution to the AHE, or even the whole AHE, can be turned off by appropriately changing the provided parameters. For example, in a system with in-plane magnetization, the AHE can be turned off by pushing the system into the fully metallic regime.  
  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:182192 Serial 6973  
Permanent link to this record
 

 
Author Rodrigues Lavor, I. url  openurl
  Title Plasmons and electronic transport in two-dimensional materials Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 219 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract This thesis presents, in its first part, an investigation on the trembling motion of wave packets known as zitterbewegung (ZBW), in multilayer graphene, as well as in moiré excitons in twisted MoS2/WSe2 hetero-bilayers. In the last few decades, the dynamics of wave packets has been subject of many theoretical and experimental studies in various types of systems such as semiconductors, superconductors, crystalline solids and cold atoms. The discovery of graphene and moiré excitons in twisted hetero-bilayers, brought two new platforms for the investigation on time evolution of wave packets and possible observation of ZBW. This trembling motion was first theoretically predicted by Schrödinger for wave packets describing particles that obey the Dirac equation. This is exactly the case of low energy electrons in graphene, as well as of moiré exciton in twisted MoS2/WSe2 under an external applied electromagnetic field. ZBW in multilayer graphene was studied both analytically and computationally, respectively, through the Green's function and split-operator methods. In this system, it is found that ZBW depends not only on the wave packet width and initial pseudospin polarization, but also on the number of layers. Furthermore, the analytical and numerical methods proposed here allow to investigate wave packet dynamics in graphene systems with an arbitrary number of layers and arbitrary potential landscapes. For moiré excitons in twisted MoS2/WSe2 hetero-bilayers, it is shown that, analogously to other Dirac-like particles, this system also exhibits ZBW when under a perpendicular applied field. In this case, the ZBW presents long timescales that are compatible with current experimental techniques for exciton dynamics. This promotes the study of the dynamics of moiré excitons in van der Waals heterostructures as an advantageous solidstate platform to probe zitterbewegung, broadly tunable by gating and inter-layer twist angle. In the second part of this thesis, a study into graphene plasmonic in van der Waals heterostructure (vdWhs) are treated in a linear response framework within the Random Phase Approximation and with support of the quantum electrostatic heterostructure (QEH), a DFT-based method. Since Dirac plasmons in graphene are very sensitive to the dielectric properties of the environment, it is possible to explore this property to probe the structure and composition of van der Waals heterostructures (vdWh) placed underneath a single graphene layer. In this way, one can achieve a layer sensitivity of a single layer and differentiate between different TMDs for heterostructures thicker than 2 layers. As a consequence of this, study, the hybridization of Dirac plasmons in graphene with phonons of transition metal dichalcogenides (TMDs), when the materials are combined in so-called van der Waals heterostructures (vdWh) forming surface plasmon-phonon polaritons (SPPPs) are also investigated. It was found that it is possible to realize both strong and ultrastrong coupling regimes by tuning graphene’s Fermi energy and changing TMD layer number.  
  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:181012 Serial 7011  
Permanent link to this record
 

 
Author Maciel de Menezes, R. url  openurl
  Title Skyrmionics and magnonics in chiral ferromagnets : from micromagnetic to atomistic control Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 222 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract The precise control of skyrmionics and magnonics in magnetic materials is key to the development of novel spin-based technology and information transport applications. Essentially, the inherent stability of magnetic skyrmions (provided by their topological charge) together with their extremely small size (down to a few nanometers) and the ultralow threshold current necessary to move them in nanostructures are the main advantages of skyrmionics. Not least, magnonics offers lower power consumption compared to electronics and the excitation of high frequency (sub-100~nm wavelength) magnons makes it possible for the creation of nanometric devices for ultrafast information transport. Even though extensive research has been carried out in recent years, the precise manipulation of skyrmions and spin waves (magnons) in nanostructures is not fully mastered and needs to be addressed before making functional skyrmionic and magnonic devices. In this thesis, we reveal multiple alternatives for the manipulation of skyrmions and spin-waves in different materials, such as bulk chiral magnets, heterochiral structures, magnet-supperconductor hybrids and two-dimentional magnetic materials. We make use of a multiscale model to numerically simulate the magnetic states at each considered material, from micromagnetic to atomistic control. We first explore the different nucleation mechanisms, activation energy, and the time evolution of the skyrmion formation in chiral magnetic films, crucial for the realization of skyrmion-based devices. We show that the skyrmion lattice is formed from the conical phase progressively, most probably by the formation of chiral bobbres, followed by the cylindrical growth of individual skyrmions from the film surface. That reflects a rod-like (one-dimensional) nucleation of the skyrmion phase, with an activation barrier of several electronvolts per skyrmion for the case of MnSi (Manganese monosilicide). In addition, we reveal the interesting blinking (creation-annihilation) behavior of skyrmions close to the phase boundary between the conical and skyrmion phases, where we recall that such switching between topologically distinct states has been proposed as a bit operation for information storage. Next, we discuss the motion of ferromagnetic and antiferromagnetic skyrmions in heterochiral magnets. We report the characteristic deflection of ferromagnetic skyrmions when moving across a heterochiral interface, where the extent of such deflection is tuned by the applied spin-polarized current and the magnitude of Dzyaloshinskii-Moriya interaction. Following, we show that the antiferromagnetic skyrmion achieves much higher velocities than its ferromagnetic counterpart, yet experiences far stronger confinement in nanoengineered heterochiral tracks, which reinforces antiferromagnetic skyrmions as a favorable choice for skyrmion-based devices. After that, we study the interesting coupling of magnetic skyrmions and superconducting vortices in magnet-superconductor heterostructures. We perform numerical simulations, based on experimental observations, to demonstrate that the stray field of magnetic skyrmions can nucleate antivortices in an adjacent superconducting film, giving rise to a hybrid topological object, the skyrmion-vortex pair, which harbor promising features for skyrmionics and quantum computing applications. We then explore the manipulation of a single skyrmion-vortex pair when currents are applied into both superconducting and magnetic parts of the heterostructure, which is of importance for the facilitated skyrmion guidance in racetrack applications. Afterwards, we make use of the high tunability of magnetic parameters in two-dimensional magnetic materials to reveal the rich phase diagram of exotic magnetic configurations in magnetic monolayers with suppressed nearest-neighbour exchange, where we show that several unique cycloidal, checkerboard, row-wise and spin-ice states are stabilized by the competition between the second-nearest-neighbor exchange, Dzyaloshinskii-Moriya, and dipolar interactions. Additionally, we show the coexistence of ferromagnetic and antiferromagnetic spin-cycloids, as well as novel types of skyrmions and chiral domain walls. Finally, in the last part of the thesis, we present the spin wave properties in the two-dimensional magnetic materials CrBr$3$ and CrI$3$. Using spin-dynamics simulations parametrized from first principles, we reveal that the spin wave dispersion in such materials can be tuned in a broad range of frequencies by strain-engineering, and that a designed pattern of strain, as well as structural defects (halide vacancies) can be turned useful in the design of spin-wave guides. Lastly, we discuss the realization of magnonic crystals by moiré-periodic modulation of magnetic parameters in van der Waals heterostructures, where we show that the several nanometer small periodicities in such samples are ideal for the interference of terahertz spin waves. Recalling the wide range of possibilities for manipulating spin waves in such two-dimensional materials, we therefore suggest these systems as a front-runner for prospective terahertz magnonic 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:184244 Serial 7019  
Permanent link to this record
 

 
Author Gonzalez Garcia, A. url  openurl
  Title Tuning the properties of group III-As in the thinnest limit : a theoretical study of single layer and 2D-heterostructures Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages xvii, 175 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract In this thesis, a first-principles research to tune the physical properties of group III-V materials in the thinnest limit is carried out. Among the different methods to tune the mechanical, electronic and magnetic properties of these graphene related materials, we use: two-dimensional (2D) multilayers, straintronics, hydrogen functionalization, and transition metal adsorption. The first part of this research is devoted to a complete characterization of the structural, electronic, mechanical and vibrational properties of 2D group III-As monolayers, obtained from density functional theory. Our findings are used to understand the contribution of the  
  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:182959 Serial 7040  
Permanent link to this record
 

 
Author Legrand, S. url  openurl
  Title Advanced chemical imaging of artworks Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 315 p.  
  Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Last century the field of heritage sciences expanded beyond imagination. The inventions of X-ray radiography and infrared reflectography allowed experts to investigate paintings below the surface as well. More recent developments led to the advent of the field of hyperspectral imaging, to which the advanced chemical imaging methods, used in this thesis work, belong. These techniques not only allow to identify the components present in artworks, but also to visualize their distribution over these objects. The resulting distribution maps permit a broader public to interpret the scientific data and to relate these results with the artwork itself. During this thesis work a range of flat artworks were investigated in a non-destructive manner using mainly two macroscopic imaging techniques: macroscopic X-ray fluorescence scanning and macroscopic Fourier transformed mid-infrared scanning in reflectance mode. The resulting images were sometimes supplemented with microscopic techniques on a minute selection of samples to fully understand the layer build-up, composition and distribution of these materials over the stratigraphy. Illuminated manuscripts pushed the interpretation of the macroscopic imaging techniques: due to the impossibility of sampling, all answers had to be obtained non-destructively. Documenting masterpieces such as the Ghent Altarpiece by means of chemical imaging techniques, helped the restoration team, assisted by the international commission to make the daring decision of manually removing the non-original paint layers. Scanning stained-glass windows allowed experts to document the panels, create situation reports, identify later infills and guide the restoration process in a more efficient manner. By initially applying non-destructive imaging techniques, many of the research/conservation questions could already be answered. Based on the resulting distribution maps, only a very limited amount of sampling was required to obtain a representative set to answer the remaining questions. In most cases the combination of multiple methods was necessary to fully understand the situation. A similar trend could be seen in the research field: the collaboration between divergent disciples was often required in order to explain all observations. In order to completely break through, the scanning speed of these techniques has to increase even more in order to cover an acceptable surface in one workday. Parallel with the operational speed, the (basic) data treatment should also be streamlined more in order to allow a broader user group to access the results. Once these two improvements are carried out, these techniques become accessible to a larger public.  
  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:176342 Serial 7420  
Permanent link to this record
 

 
Author Xie, Y. url  openurl
  Title Bioreactor strategies for sustainable nitrogen cycling based on mineralization/nitrification, partial nitritation/anammox or sulfur-based denitratation Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages iv, 205 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In the biogeochemical flows on Earth, the reactive nitrogen (Nr) level has three times surpassed the safe boundary. The severe transgression of this boundary goes against sustainable planetary development. The modern food production process excessively relies on synthetic Nr fertilizers from the Haber– Bosch process. However, the massive loss of valuable nitrogen resources (i.e., 78-89%) from agriculture has been causing severe nitrogen cascade. Besides, the domestic wastewater in some local areas is discharged without proper treatment, making it a nonnegligible source of Nr pollution for local water bodies. Anthropogenic activities keep pumping out Nr pollution via point-source and non-point-source (NPS) emissions. Compared to the NPS emissions, point sources give visible and identified waste streams. It is vital to intervene the nitrogen cascade from point sources and facilitate humanity back to the safe Nr boundary. The collected and collectible Nr streams from food production, waste management, and recycling secondary raw materials can be used as waste-based fertilizers for agricultural cultivation. Besides the well-investigated recovery of inorganic Nr, organic Nr accounts for a massive Nr proportion on the Earth. Proper handling and treatment make these useful organic fertilizers for soil-based cultivation. However, these organic Nr fertilizers cannot directly apply to fertigation or hydroponic cultivation systems, and further biological conversion via nitrogen mineralization and nitrification to nitrate is essential. Besides the direct Nr cycling, the indirect Nr cycling ‘over the atmosphere’ should also be considered. In this way, the nitrogen cycle can be completed via converting the waste Nr back to nitrogen gas (i.e., Nr removal) and then synthesizing into Nr again. The municipal wastewater treatment plants receive a vast amount of low-strength Nr wastewater (mainly as ammonium) daily. Compared to the conventional nitrification/denitrification process, partial nitritation/anammox (PN/A) is considered a resource- and cost-effective technology for wastewater with a low COD/N ratio. Moreover, the novel autotrophic denitratation/anammox process could be a good Nr removal process for wastewater containing both ammonium and nitrate. This Ph.D. thesis aimed to develop Nr recovery, conversion, and removal bioreactor strategies for different types of waste streams and biomass. Nr recovery was investigated on high-strength Nr waste streams for fertigation or hydroponic applications in Chapters 2 and 3. On the other hand, Nr removal was studied on the medium- to low-strength Nr waste streams in Chapters 4 and 5. In Chapter 2, a novel mineralization and nitrification system was proposed, producing nutrient solutions from solid organic fertilizers for hydroponic systems. Batch tests showed that aerobic incubation at 35°C could realize the NO₃⁻-N production efficiency above 90% from a novel microbial fertilizer. Subsequently, in the stirred tank bioreactor test, NO₃⁻-N production efficiency stabilized in a range of 44-51% under the influent loading rate of 400 mg TN L⁻¹ d⁻¹ at a 5-day HRT. Using Ca(OH)₂ and Mg(OH)₂ as pH control reagents generated the nutrient solutions with different P, Ca, and Mg nutrient levels. After modeling the nutrient balancing process, the proportion of organic-sourced NO₃⁻-N in the Hoagland nutrient solution (HNS) of Ca(OH)₂ scenario was 92.7%, while only 37.4% in the Mg(OH)₂ scenario. Compared to commercial scenarios, the total costs of the organic-sourced HNS can be cost-competitive for hydroponic cultivation. In Chapter 3, the Nr recovery as nitrate (NO₃⁻-N) from diluted human urine (around 670 mg N L⁻¹) was explored in a trickling filter (TF) for the first time. A novel concept of in-situ integrating the TF system into hydroponic systems was proposed as meaningful progress towards sustainable agriculture. The difference between synthetic and real urine in nitrification efficiency was found to be negligible. The full nitrification of alkalinized real urine was realized in the pH-controlled TF by calcium hydroxide (Ca(OH)₂) at around pH 6. The TF could handle different urine collection batches and maintain relatively stable nitrification performance, with NO₃⁻-N production efficiency and rate of 88±3% and 136±4 mg N L⁻¹ d⁻¹, respectively. The optimal HLR to realize this nitrification performance was 2 m³ m⁻² h⁻¹, with energy consumption of 1.8 kWh electricity kg⁻¹ NO₃⁻-N production. Ca(OH)₂, as a cheap base, its triple advantages on urine alkalinization, full nitrification, and macronutrient supplementation were successfully demonstrated in our proposed concept. In Chapter 4, towards more sustainable wastewater treatment, the feasibility of one-stage partial nitritation/anammox (PN/A) was investigated in three parallel packed-bed trickling filters (TFs), with three types of carrier materials of different specific surface areas. Synthetic wastewater containing 100-250 mg NH₄⁺-N L⁻¹ was tested to mimic medium-strength household waste streams after carbon removal. Interestingly, the cheap carrier based on expanded clay achieved similar rates as commercially used plastic carrier materials. The top passive ventilation combined with an optimum hydraulic loading rate of 1.8 m³ m⁻² h⁻¹ could reach approximately 60% total nitrogen (TN) removal at a rate of 300 mg N L⁻¹ d⁻¹. A relatively low NO₃⁻-N production (13%) via PN/A was achieved in TFs. Most of the TN removal took place in the top compartment, where anammox activity was the highest. Energy consumption estimation (0.78 kWh electricity g⁻¹ N removed) suggested that the proposed process could be a suitable low-cost alternative for nitrogen removal. In Chapter 5, coupling sulfur-driven denitratation (SDN) with anammox was proposed to treat the wastewater containing both NO₃⁻-N and NH₄⁺-N, like the secondary effluents of mainstream PN/A processes. To explore the feasibility of sufficient and stable NO₂⁻-N accumulation via SDN in the long term, the effects of pH setpoints, residual NO₃⁻-N level, and biomass-specific NO₃⁻-N loading rate (BSNLR) were investigated. Alternating the pH setpoints between 7.0 and 8.5 could temporarily stimulate the NO₂⁻-N accumulation. Both the residual NO₃⁻-N and BSNLR showed highly positive correlations with the NO₂⁻-N accumulation efficiency. Under the control of pH 8.5, 1.0±0.8 mg NO₃⁻-N L⁻¹ and 150±42 mg NO₃⁻-N g⁻¹ VSS d⁻¹, SDN could produce 6.4±1.0 mg NO₂⁻-N L⁻¹ in the short term. Thiobacillus members may play a crucial role in managing the NO₂⁻-N accumulation, but the reduction of abundance and possible adaptation significantly impaired the efficacy of control strategies in the long run. Overall, novel technologies have been proposed to sustainably convert Nr in waste streams and biomass. The decision for Nr recovery versus removal and synthesis should be based on specific cases with the best environmental, economic, and human-health sustainability. In the future, the Nr management concepts should be further improved to make the nitrogen cycle more sustainable with higher resource use efficiency and less Nr emissions to the environment. Although the thesis is mainly focused on limited types of Nr waste streams, it pointed out the direction of sustainable Nr management and could facilitate the Nr back to the safe boundary in the long run.  
  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:182099 Serial 7563  
Permanent link to this record
 

 
Author Sleegers, N. openurl 
  Title Cephalosporin antibiotics : electrochemical fingerprints and redox pathways investigated by mass spectral analysis Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 208 p.  
  Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)  
  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:181014 Serial 7588  
Permanent link to this record
 

 
Author Zhang, L. openurl 
  Title Characteristic diagnosis of atmospheric discharge plasma and kinetics study of reactive species Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages XVIII, 148 p.  
  Keywords Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Low-temperature plasma has received extensive attention due to its promising application prospects in the field of air pollutants degradation and energy conversion. To fulfill the need for particular applications, constructing stable plasma sources and investigating the interaction mechanisms between plasma and substances have been hot research topics. This thesis reports the diagnosis and improvement of plasma sources, diagnosis of the active species in plasma and a modeling study of chemical kinetics processes. The main research contents are as follows: In Chapter 3, a diffuse sine AC dielectric barrier discharge (DBD) is successfully obtained by optimizing the electrode structure. It is found that using double-layer dielectric plates can limit the discharge current intensity and significantly improve the discharge uniformity. The electrical characteristics and gas temperature with different operating time show that the discharge stability is also improved by using double-layer dielectric plates. In Chapter 4, nanosecond pulses are employed to generate diffuse DBD plasmas. Three main discharge stages are distinguished by ICCD images, i.e., the streamer breakdown from the needle tip to the plate electrode, the regime transition from streamer to diffuse plasma, and the propagation of surface discharge on the plate electrode surface. The chapter reveales that in nanosecond pulsed discharges the vibrational temperature of N2 increases with the discharge duration, while the rotational temperature mainly stays constant, which means electron energy is transferred into the vibrational levels, but gas heating is not obvious during the discharge pulse. In Chapter 5, both sine AC DBD and nanosecond pulsed DBD, studied in Chapter 2 and 3, are used for formaldehyde degradation. It is found that nanosecond pulsed DBD has more homogenous characteristics, better stability, and lower plasma gas temperature. Moreover, the energy consumption of nanosecond pulsed DBD is much lower than that of AC DBD. In Chapter 6, a 0D chemical kinetics model is developed to investigate the underlying plasma chemistry of methane dry reforming in a nanosecond pulsed discharge. An overview of the dominant reaction pathways of CO2 and CH4 conversion into the major products is given. Furthermore, most of the CO2 molecules are populated into vibrational states during the pulse. Hence, the vibrational states of CO2 play an important role in its dissociation process. In general, this PhD thesis contributes to a better insight in the mechanisms of sinusoidal AC DBD and nanosecond pulsed DBD plasmas and their applications, i.e., decomposition of formaldehyde and dry reforming of methane.  
  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:183166 Serial 7605  
Permanent link to this record
 

 
Author Alemam, E. url  openurl
  Title Cleaning of wall paintings by Polyvinyl alcohol–Borax/Agarose (PVA–B/AG) double network hydrogels : characterization, assessment, and applications Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 184 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)  
  Abstract Wall paintings make up an important section of cultural heritage. They resemble time portals that can be used to travel back into the past and witness the life of our ancestors. In these paintings, the ancient artists depicted the different aspects of their life, such as cooking, baking, farming, manufacturing, as well as thoughts and beliefs. Unfortunately, wall paintings are susceptible to degradation over time in the form of the accumulations of dirt and deposits on the painted surfaces and loss of adhesion of the paint layers at the surface. Therefore, the removal of these deposits is one of the primary duties of conservator-restorers. Such operations are intended to restore the painted surface to a condition close enough to its original state. Since cleaning artworks may cause undesirable physicochemical alterations and is nonreversible, the proper cleaning procedure should be adopted. In this regard, numerous gels have been developed and exploited for the cleaning of various artwork surfaces. Lately, polyvinyl alcohol-borax (PVA-B) and agarose (AG) hydrogels have been widely employed as cleaning materials by conservator-restorers. However, both hydrogels have shown limitations in specific cleaning practices. In this work, we investigated a new double network hydrogel based on blending PVA-B and agarose to avoid the limitations posed by the constituting hydrogels. For this reason, a detailed characterization of the PVA–B/AG double network hydrogel was performed, including chemical structure, liquid phase retention, mechanical strength, rheological behavior, and self-healing behavior of various PVA-B/AG hydrogels. These new hydrogels revealed better properties than PVA-B and agarose hydrogels and obviated their limitations. A laboratory experiment on the removal of deteriorated Paraloid® B72 proved that the PVA-B/AG hydrogel loaded 10%/10% MEK/1-PeOH was able to remove these layers efficiently. Therefore, the hydrogel was tested on a wall painting from the Temple of Seti I in Abydos – Egypt. It removed the glossy/darkened consolidant from the wall painting and restored the original matt appearance of the painted surface. In another application on the painted ceiling of the same temple, the hydrogel was tested for removing thick soot layers. The hydrogel formulation (loaded with 5% ammonia, 0.3% ammonium carbonate, and 0.3% EDTA) removed these layers with no noticeable damage to the paint layers. In a wide-scale application of the hydrogel (loaded with 10% propylene carbonate), it removed a highly deteriorated varnish layer from a 19-c wall painting. All the traditional cleaning methods employed caused damage to the paint layers, proving that gel cleaning can be a safer cleaning alternative in some cases.  
  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:183381 Serial 7671  
Permanent link to this record
 

 
Author Blidar, A.-M. url  openurl
  Title The development of sensitive and selective electrochemical methods for the detection of antibiotics Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 139 p.  
  Keywords Doctoral thesis; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)  
  Abstract The discovery of antibiotics represented one of the greatest breakthroughs in medicine. Their success combined with an increasing intensive use is apparently bound to be also their undoing. This is due to the development of acquired antibiotic resistance, leading to inefficient antibiotherapy and even to the impossibility of treatment and death. The development and spread of antibiotic resistance are fueled by the widespread presence of trace levels of antibiotics residue, in various media, from environment to aliments. One of the solutions is the rigorous monitoring of the levels of antibiotics, which in term requires an almost constant development of new, more accessible analytical methods, especially screening methods, capable of decentralized analysis. In this direction, the electrochemical detection of antibiotics represents a very viable alternative. In this context, the aim of this thesis was to develop new electrochemical methods for the detection of antibiotics by employing and expanding on several strategies, like biomimetic sensors and electrochemical fingerprinting. Five studies were described in this thesis, that can be roughly divided in three categories, based on the analytical strategy employed. The first group is represented by direct electrochemical methods. The second group focuses on the use of biomimetic elements, molecularly imprinted polymers and aptamers. The hyphenation of electrochemical methods with other analytical methods was explored in the last group. In the last study, included in this group, the singlet oxygen-based photoelectrochemical approach was used for the detection of a phenolic antibiotic, rifampicin. The originality of the thesis consists in the testing and development of new approaches to various strategies used in electrochemical detection, revealing new insights in the field of electrochemical detection of antibiotics. The complex electrochemical fingerprint and the mechanism of the electrochemical oxidation were created and investigated, respectively, for the antibiotic vancomycin. New sensitive nanoplatforms were prepared by employing and combining new protocols. Additionally, important contributions were brought through the study involving the singlet oxygen-based detection of rifampicin. We demonstrated how a photocatalyst can exhibit analyte selectivity by strongly interacting with a complex phenolic compound, rifampicin. Summing up, the studies presented in this thesis will have an important impact in the field of electrochemical detection of antibiotics.  
  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:182955 Serial 7804  
Permanent link to this record
 

 
Author Shaw, P. url  openurl
  Title Dual action of reactive species as signal and stress agents in plasma medicine : combined computational and experimental research Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 191 p.  
  Keywords Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Center for Oncological Research (CORE)  
  Abstract Reactive oxygen and nitrogen species (RONS) generated by cold atmospheric plasma (CAP) can activate discrete signaling transduction pathways or disrupt redox cellular homeostasis, depending on their concentration. This makes that CAP possesses therapeutic potential towards wound healing, cancer, and other diseases. In order to effectively use CAP in the clinic, a clear understanding of the interaction of RONS with biomolecules (lipids, proteins and nucleic acids) from the atomic to the macro scale, and their biological significance, is needed. In this work, I have therefore studied the dual role of CAP-derived RONS, i.e., (i) in the signaling pathways involved in wound healing, and (ii) in their reaction with biomolecules to cause oxidation-mediated damage. I performed computer simulations to provide fundamental insight about the occurring processes that are difficult or even impossible to obtain experimentally. Furthermore, next to computational studies, I used both 2D and 3D tissue cultures. 3D model allows proliferation in a more physiologically relevant geometry that stimulates the production of extracellular matrix proteins. I investigated the treatment of human gingival fibroblasts with low doses of CAP-generated RONS. This treatment demonstrated that it can inhibit colony formation but does not induce cell death, induce the expression of metalloprotease proteins, induce extracellular matrix degradation, and promote cell migration, which could result in enhanced wound healing. In contrast, at high concentrations, RONS can disrupt the cell membrane integrity and induce cancer cell death through oxidative stress-mediated pathways. I discovered how oxidation of the cell membrane (lipid-peroxidation) can facilitate the access of a drug (Melittin) into cancer cells, and in this way, reduce the required therapeutic dose of Melittin in melanoma and breast cancer cells (demonstrated using in vitro, in ovo and in silico approaches). Furthermore, I studied how excessive lipid-oxidation in chemoresistant pancreatic cancer cells promotes ferroptotic cell death. This was due to the stimulation of the iron-dependent Fenton reaction by targeting a redox specific signaling network. However, upon oxidative stress, cells protect themselves via a sophisticated intracellular antioxidant system that involves the regulation of glutathione/glutathione peroxidase 4 (lipid repair enzyme). Cancer cells exhibited increased levels of intracellular RONS due to their hyper metabolism, leading to high expression of anti-oxidant systems. I therefore focus on the effect of reactive species on the intracellular anti-oxidant system and corresponding DNA damages in both temozolomide-sensitive as well as temozolomide-resistant glioblastoma spheroids, in a 3-dimensional tumor model with a more complex tumor microenvironment than cell monolayers.  
  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:183751 Serial 7828  
Permanent link to this record
 

 
Author Cui, Z. file  openurl
  Title Experimental and theoretical study on SF6 degradation by packed-bed DBD plasma Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Sulfur hexafluoride (SF6), as a man-made gas, is widely used in power industry, semiconductor industry and metal-processing industry. However, SF6 is a greenhouse gas and its global warming potential is 23500 times that of CO2. Besides, SF6 is very stable, with a lifetime in the atmosphere for more than one thousand years. Under natural conditions, only the ultraviolet light can make it slowly decomposed. Thus, the emission of SF6 has a great threat to the environment. In recent years, with the development of our national economy, the use of SF6 increased dramatically. And 90% of the SF6 emissions come from the power industry. In the meantime, the emission of SF6 exists a ‘hysteresis effect’, as many of the SF6-gas insulation equipment will retire in next decades, the emission of SF6 may increase sharply, and this may put great pressure on the environment. Therefore, it’s necessary to make efforts in controlling and treating the SF6 emission. Among the SF6 abatement technologies, the non-thermal plasma(NTP) represented by the dielectric barrier discharge(DBD) can effectively degrade SF6 and is suitable for large-scale industry applications. However, its energy efficiency still gets room for improvement and this kind of method has a defect that it’s hard to regulate the degradation by-products. Therefore, this paper proposed the combination of the packed bed reactor and the DBD technology to form a packed DBD discharge system for SF6 degradation, so that to further improve the energy efficiency and regulate the selectivity of by-products. By experiment and simulation research, the following innovations have been achieved: (1) Based on the packed bed DBD platform, the power parameter and gas-phase parameters of SF6 degradation were studied. It was found that the discharge process was significantly enhanced with the addition of packing particles, and the discharge energy efficiency was improved. The increase of input voltage can obviously increase the degradation rate, but reduces the energy efficiency. The increase of SF6 initial concentration and gas flow rate can improve the energy efficiency, but reduce the degradation rate. Therefore, both degradation rate and energy efficiency should be considered in deciding basic experimental conditions. (2) Active gases, such as O2, H2O and NH3, could effectively promote the degradation rate of SF6, and changed the product selectivity. In our packed bed DBD system, O2 and H2O have the optimal concentration conditions, which are 2% and 1%, respectively. The addition of O2 can promote the generation of S-O-F products, and inhibit the selectivity of SO2, while the addition of H2O had the opposite effects. In addition, the synergistic degradation of NH3 and SF6 will produce solid products, such as NH3HF, NH4HF2 and elemental S. For gaseous products, the increase of NH3 will lead to the generation of SO2 in the final degradation products and inhibit the generation of S-O-F products. (3) Different kinds of packing materials have great impacts on the degradation system in the discharge parameters, degradation rate and energy efficiency, as well as the products distribution. In the experiment, we compared the degradation results in three systems: glass beads packing, γ-Al2O3 packing and no-packing system. The packing of glass beads effectively improved the discharge voltage amplitude and discharge power, while had a limited effect on the equivalent capacitance of the dielectric. Besides, γ-Al2O3 packing had little effect on voltage amplitude, but obviously increased the equivalent capacitance of the dielectric. Furthermore, the degradation rate and energy efficiency in γ-Al2O3 system was higher than that of glass bead system. For products selectivity, γ-Al2O3 system was more desirable, where S-O-F type of product selectivity was suppressed and the SO2 selectivity increased significantly. By contrast, the glass beads system hardly affected the product selectivity. This results are presumably due to the relatively high dielectric constant of γ-Al2O3 particles and γ-Al2O3 itself may act as a reactant or a catalyst participating in the degradation reactions. (4) The size and status of the packing particles also have significant effects on the degradation process. The systems packed with 1, 2 and 4mm γ-Al2O3 particles for SF6 degradation were compared, and the 2mm system had the best performance, which may because the 2mm system had a good balance between the active contact area and the gas residence time. In addition, the packing pellets suffered from a hydration process slightly reduced the discharge parameters in the γ-Al2O3 packing system and significantly reduced the degradation rate was, which may because the H2O molecules pre-occupied the active sites on the γ-Al2O3 surface and reduced the discharge process. (5) Based on density functional theory (DFT), the degradation process of SF6 in the packed bed DBD system was studied at atomic scale. It was found that the SF6 can occur a physical adsorption at AlⅢ active sites on γ-Al2O3 surface. The activation barrier for the first degradation step of SF6 on γ-Al2O3 surface is much lower than in gas phase, which proved that the SF6 molecule is activated on the γ-Al2O3 surface. In addition, the plasma may affect the γ-Al2O3 surface to generate excess electrons or external electric fields. This two effects can change the adsorbed SF6 molecules from physical adsorption to chemisorption, together with an obvious stretching of S-F bonds, indicating that the plasma surface effects prmote the activation and decomposition of SF6 molecules. Furthermore, the stepwise degradation process of SF6 on γ-Al2O3 surface were investigated. The influence of radicals produced by plasma on the degradation process was analyzed. It was found that via Eley–Rideal (ER) reactions, high-energy radicals could effectively reduce the activation barriers and promote the surface reactions. Finally, the degradation mechanism of SF6 molecules in the packed bed plasma system was summarized, which may provide a theoretical basis for the study of harmless degradation of SF6. Keywords: SF6; Packed Bed DBD; Discharge Parameters; Products Analysis; Degradation Mechanism  
  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:180819 Serial 7946  
Permanent link to this record
 

 
Author Zhu, W. url  openurl
  Title Microbial resource management for mainstream partial nitritation/anammox : strategies to enhance the nitrogen conversion efficiency Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 207 p.  
  Keywords Doctoral thesis; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract This thesis provides three potential ways to enhance the nitrogen removal efficiency of mainstream partial nitritation/anammox (PN/A), a key technology to enable energy-positive sewage treatment. In Chapter 1, the typical technologies to promote nitrogen removal efficiency are summarized. In Chapters 2 and 3, the concept ‘winter bioaugmentation with stored summer surplus sludge’ is proposed. Applying that, a cost-effective sludge preservation strategy is required. Preserving PN/A biomass without cooling and redox adjustment proved to be the cost-effective strategy. The reactivation of these stored sludges was also tested in low-temperature systems (15 and 10℃). Respectively 56% and 41% of granules activity compared to pre-storage activity (after Arrhenius-based temperature correction) could be recovered within a month (41% and 32% for flocs activity). In the end, the stored AnAOB bioaugmentation was successfully validated in the lab (20℃). In Chapter 4, a return-sludge nursery concept, applying the sidestream nitritation and blending the resulting effluent with mainstream effluent to achieve an intermediate temperature and nitrogen concentrations, is proposed. That led to a 33 – 36% increase in nitrogen removal efficiency. Arrhenius’ expectations (10 ℃ higher temperature, θ = 1.09) could only explain 49-51% of the activity increase in the nursery reactor, pointing to the role of other factors, e.g., the ~400% elevated electrical conductivity (15-16%), the 56-335% higher effluent nitrogen concentrations (12-14%), and the synergy and unknown factors (20-23%). Thus, the return-sludge biostimulation approach could also enhance nitrogen efficiency in the mainstream. In Chapter 5, the N2O emissions, linked to three typical nitrite-oxidizing bacteria (NOB) suppression strategies (low dissolved oxygen (DO) level, free ammonia (FA), and free nitrous acids (FNA) treatments) were tested in a biofilm system. A low emerged DO level (~0.60 mg O2 L-1) was effective to suppress NOB activity and decrease N2O emissions, but NOB adaptation gradually appeared after 200 days. Further NOB inhibition was successfully achieved by periodical (3 hours per week) FA (~30 mg NH3-N L-1) or FNA (~3 mg HNO2-N L-1) treatments. The FA treatment promoted N2O production, while the FNA treatment had no effect. Thus, PN/A systems should be operated at relatively low DO levels with periodical FNA treatment. In Chapter 6, the major findings proposed and the main conclusions drawn in this thesis are outlined. Beyond that, the possible design of a mainstream PN/A configuration that combined all described three technologies is demonstrated. Overall, the novel insights from this thesis potential to improve nitrogen removal efficiency in the mainstream.  
  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:184236 Serial 8245  
Permanent link to this record
 

 
Author Marchetti, A. url  openurl
  Title Novel insights and approaches for the analytical characterization of tangible cultural heritage objects Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 333 p.  
  Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Cultural heritage represents the vehicle of our cultural identity, handed over from past to future generations throughout human history. As a repository of fundamental cultural and social values, the preservation of all forms of cultural heritage is a responsibility of every society and of humankind as a whole. When it comes to tangible cultural heritage, preservation of heritage translates into preservation of objects and, therefore, of the materials they are constituted of. This crucial task relies heavily on the application of scientific analytical methods to answer material and conservation-related questions. ​ ​ The fundamental contribution of this analytical approach led, in the past decades, to an ever-deepening understanding of the factors governing the degradation of cultural heritage. However, the extreme complexity of the heritage object-environment system results in a massive research field, which inevitably presents relevant open questions. This is where the present PhD work comes into play, attempting to fill knowledge gaps in literature by starting from specific case studies and un-answered research questions. ​ ​ The multianalytical research conducted during this PhD unraveled fundamental information on the properties governing the reactivity and long-term behavior of different classes of materials, from α-brass in an indoor environment to artists’ pigments in the presence of light, moisture and soluble particulate matter (PM). The paramount importance of the synthesis conditions on the composition, physical properties and reactivity of heritage materials was also demonstrated, in particular for stable lead pyroantimonate and unstable Geranium lake artists’ pigments. Moreover, the study and characterization of specific heritage objects, namely a series of 16th century reliquary altarpieces and the painting L’Arlesienne, by Vincent Van Gogh, allowed to obtain relevant insights into their composition and on potential risks for their conservation. The challenging nature of the samples considered, created the perfect opportunity to test an innovative spectroscopic technique, optical photo-thermal IR (O-PTIR), for the characterization of heritage materials. Striking results were obtained, highlighting a great potential for the application of this non-destructive sub-micron molecular spectroscopy to the analysis of cultural heritage. Finally, in the last section of this work, strategies to implement the continuous monitoring of PM levels in indoor environmental quality studies were also considered, with a particular focus on the identification of environmental hazards for the collections housed in specific conservation environments (War Heritage Institute in Brussels and St. Martin’s church in Aalst, BE).  
  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:177849 Serial 8319  
Permanent link to this record
 

 
Author Cong, S. file  openurl
  Title Numerical study on low-pressure hollow cathode argon arc plasma Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages XIX, 126 p.  
  Keywords Doctoral thesis; Philosophy; Educational sciences; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The low-pressure hollow cathode discharge made of a hollow circular tube and an anode is a type of simple structure discharge system. In particular, under the arc discharge mode, hollow cathodes have high plasma density and energy density with a wide range of adaptability of pressure and current. Low-pressure hollow cathode arc (HCA) discharges have been widely used as plasma sources in various fields such as manufacturing, vacuum welding, and aerospace since the 1960s. Despite the early experimental and applied researches on low-pressure HCA discharges, the basic theoretical study was relatively lagged much behind, resulting in many unanswered questions, such as the optimal discharge operating parameters, the power deposition inside the cathode, the causes of plasma instability, and how to effectively reduce cathode erosion and so on. Due to the special discharge structure of the hollow cathode, it is difficult to make an accurate experimental diagnosis, so a reasonable numerical simulation is an effective study method. However, up to now, there is still a lack of complete and effective numerical models which can evaluate various physical fields in the low-pressure hollow cathode discharges. To address the above problems and difficulties, a comprehensive and self-consistent 2D multi-physical coupling numerical model based on a commercial program of finite element method, the COMSOL Multiphysics, was provided in this paper. The model involves plasma transport, arc flow and heat transfer, and cathode thermal equilibrium, and can consider the effect of an applied magnetic field. The processes of secondary electron emission, thermal-field electron emission, ions and backflow high-energy electrons bombardment, and thermal radiation from the cathode surface are considered in the cathode thermal equilibrium process. Based on the above background, this paper works from the following aspects: In Chapter 1, the basic concepts of low-pressure HCA discharge including the hollow cathode effect, the basic characteristics, and operation modes were introduced firstly; Secondly, the application fields, development history, and overseas and domestic research status of hollow cathode discharge were reviewed; finally, the problems were presented and the research background was explained, and the research purpose of this paper was clarified. In Chapter 2, a complete and self-consistent numerical model of low-pressure hollow cathode discharge was proposed based on the fundamental theory and assumptions, and the set of control equations and boundary conditions in the model were elaborated. In addition, the electron energy distribution function, the collision processes, the solving tools of this model, and calculation schemes were introduced in detail. Finally, a validation example was given to test the rationality and applicability of the numerical model. In Chapter 3, the fundamental plasma properties of low-pressure hollow cathode arcs were investigated. Firstly, the ion Joule heating effect was studied. The results showed that the temperature distributions of the arc and cathode are only able to approach the experimental measurements after considering the ion Joule heating, which shows that the Joule heating of ions is crucial for the heating of the arc plasma. Secondly, by comparing the radial distribution of electron and ion density inside the cathode, the structure of the cathode sheath could be simulated well using this model. Finally, it was shown that the thermal radiation from the cathode surface is an important cooling mechanism of the cathode and only under higher surface emissivity can balance the larger heat flow given by the plasma to the cathode, and the temperature distribution of the cathode shows a non-monotonic increasing trend and is consistent with the profile of experimental measurement so that the so-called active zone is formed. In Chapter 4, the power deposition in the low-pressure HCA was studied in simulation. Two main aspects were considered: the power deposition into particles (both electrons and heavy particles) and the power deposition onto the cathode. It was found that the deposited power into particles increases with the rise of discharge current, but there is no effect on the total power deposition onto the cathode. In high-density plasmas, Coulomb collisions between electrons and ions also become very important, especially since a portion of the deposition energy on heavy particles comes mainly from the energy transfer from electrons to ions. It was also found that regardless of external parameters, half of the power deposition onto the cathode always comes from the particle contribution, while the other half is the net contribution of heat transfer and cathode radiation. The HCA model also allows the simulation of multiple discharge modes for low-pressure HCA discharges over a wide range of gas flow rates. It was also shown that the discharge operating conditions and the external magnetic field can change the distribution of the particle flow on the cathode wall. In Chapter 5, the ion sputtering erosion process on the cathode was simulated by coupling the HCA numerical model with the moving grid technique. The results showed that the ion sputtering erosion on the cathode depends on the ion flux and the plasma potential near the cathode wall and that their distribution and magnitude jointly determine the erosion morphology of the cathode. It was also found that the location of the most severe erosion on the cathode is located in the region of the densest ion flux on the cathode wall, rather than in the longitudinal correspondence with the central region of the internal positive column (IPC). The external magnetic fields can mitigate the cathode erosion and reduce the erosion depth, but stronger magnetic fields lead to a concentration of current density at the cathode tip, which can enhance erosion slightly at the cathode outlet end. Finally, the conclusions and innovation highlights were summarized, and prospects for future work were discussed.  
  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:178725 Serial 8323  
Permanent link to this record
 

 
Author Van Hal, M. url  openurl
  Title Photo(electro)catalytic air purification and soot degradation with simultaneous energy recovery Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages XXXII, 203 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Today’s society is increasingly challenged by a range of urgent environmental problems. Air pollution is one of these pressing topics. This thesis will mainly focus on the degradation of volatile organic compounds (VOCs) and particulate matter (PM) – more specifically soot. A second globally urging topic is the quest for sustainable energy production. To simultaneously target both environmental problems, a photoelectrochemical (PEC) cell will be studied in this thesis, combining air purification and sustainable energy production in a single device. Photocatalysis is used at the anode of the PEC cell to drive the air purification process, while the energy contained in the degraded compounds is (partially) recovered at the cathode, either as H2 gas or electricity. The first two experimental chapters focus on the proof of concept of such an unbiased all-gas phase PEC cell targeting VOC degradation, using both TiO2- and WO3-based photocatalysts. In the two following experimental chapters the photocatalytic soot oxidation capacity of these TiO2- and WO3-based photocatalysts was studied. In the final experimental chapter the previously obtained results were combined, striving towards an efficient, sunlight-driven and soot-degrading waste gas-to-energy PEC cell.  
  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:184521 Serial 8378  
Permanent link to this record
 

 
Author Daems, E. url  openurl
  Title Shaping up oligonucleotides : aptamer-target recognition investigated by native mass spectrometry Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 235 p.  
  Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Aptamers are short, synthetic DNA or RNA molecules that are characterized by a specific 3D conformation which enables specific target recognition. Aptamers are promising tools in many application fields from sensing to therapeutics. One of the major challenges in the aptamer field is understanding the relationship between the sequence and what determines the higher-order structure and specific interactions with targets. Therefore, this PhD thesis focuses on the use of different mass spectrometry (MS) based approaches to characterize aptamers and their interactions. Several of these approaches are already widely applied to study other biomolecules, such as proteins, but are still largely unexplored for aptamers and oligonucleotides in general. A first focus was put on obtaining information on the higher-order structure and conformational stability of aptamers using a combination of MS and with ion mobility (IM) spectrometry by performing collision-induced unfolding (CIU) experiments. CIU was shown to hold great promise to analyze the conformational dynamics and gas-phase stabilities of aptamers. Next, the capabilities and limitations of native IM-MS for the analysis of noncovalent interactions of aptamers were demonstrated. The conformational behavior and interactions of cocaine-binding aptamers were studied and it was found that relative binding affinities of aptamers that only differ slightly in sequence and structure can be determined using native MS. Moreover, native IM-MS allowed the detection of small conformational changes upon binding of a target, which were found to be dependent on the binding mode of the aptamer. An adaptive binding mechanism was suggested for flexible aptamers that require more reorganization upon binding. In the final part of this thesis, the importance of thoroughly characterizing and validating aptamer-target interactions before using them in an application was emphasized. Moreover, the gathered insights were applied in our own development of a proof-of-concept aptamer-based sensor. This was shown by investigating the interactions of ampicillin aptamers which were found to not bind the target they were selected for in the first place. A multi-analytical approach combining complementary techniques was used for this purpose since no single technique is generally applicable to characterize all aptamers and their interactions and to obtain a comprehensive picture of the aptamer-target interactions. Furthermore, such multi-analytical approach was used to characterize a testosterone-binding aptamer while developing an aptamer-based electrochemiluminescent sensing strategy for this target. This shows the importance of native MS, in combination with other techniques, to thoroughly understand the aptamer-target interactions in the development of a designed application.  
  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:178116 Serial 8517  
Permanent link to this record
 

 
Author Van Loenhout, J. url  openurl
  Title Targeting pancreatic ductal adenocarcinoma and glioblastoma with oxidative stress-mediated treatment strategies : focus on tumor cell death and modulation of the tumor microenvironment Type (up) Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 167 p.  
  Keywords Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Center for Oncological Research (CORE)  
  Abstract Pancreatic ductal adenocarcinoma (PDAC) and glioblastoma multiforme (GBM) are two of the most malignant solid tumor types with poor survival rates, which underscore the urgency of novel and efficacious treatment strategies. Within the last decade, immunotherapy has been established as a breakthrough in cancer therapy. This mainly has been driven by the clinical data and approval associated with several immune checkpoint inhibitors (e.g. anti-CTLA-4 and anti-PD-1/L1). Despite the clinical benefit in specific tumor types, these inhibitors have not yet fulfilled their promise in low immunogenic tumors such as PDAC and GBM. Oxidative stress in cancer cells due to elevated reactive oxygen species (ROS) and an inability to balance intracellular redox state has recently been highlighted as promising target for anticancer treatment strategies with possible immunogenic effects. In this PhD dissertation, I investigated novel oxidative stress-mediated treatment approaches to target PDAC and GBM and to enhance immunogenicity by inducing immunogenic cell death (ICD). In the first part of this thesis (chapter 2), I reviewed the mechanistic responses of cancer cells towards different oxidative stress-inducing treatment strategies and their immunomodulating effects. The resulting literature demonstrated that different exogenous and endogenous ROS-inducing therapies show direct and indirect immunomodulating effects, which can be either immunostimulatory or immunosuppressive. One of the indirect immunostimulatory effects of the ROS-mediating therapies is the capacity of inducing immunogenic cell death (ICD) in tumor cells, which can increase the immunogenicity and consequently can trigger an antitumoral immune response. In chapter 3, I investigated a novel exogenous ROS-inducing treatment method, namely cold atmospheric plasma, to determine the therapeutic and ICD-inducing effects in PDAC, in vitro. I revealed that plasma-treated PBS (pPBS) has the potential to induce ICD in pancreatic cancer cells (PCCs) and to reduce the immunosuppressive tumor microenvironment (TME) by attacking the tumor supportive pancreatic stellate cells (PSCs). Although the cell death induced in PSCs was non-immunogenic as seen by the lack of danger-associated molecular patterns (DAMPs) emission and DC activation, I showed that pPBS could disrupt the physical barrier and lower the immunosuppressive secretion profile (lower TGF-β) of PSCs. In contrast, DAMPs were released by PCCs after treatment with pPBS which resulted in activation and maturation of DCs and a more immunostimulatory secretion profile (higher TNF-α, IFN-γ). Hence, indirect plasma treatment via pPBS has the potential to enhance immunogenicity in PDAC by triggering ICD and by attacking the immunosuppressive PSCs. Tumor cells can evolve adaptation mechanisms to protect themselves against intrinsic oxidative stress by upregulation of pro-survival molecules and their antioxidant defense system to maintain the redox balance. As such, tumor cells can become resistant towards exogenous ROS-inducing therapies, like plasma. Dual targeting of the redox balance of tumor cells by increasing exogenous levels of ROS and inhibiting the antioxidant defense system can maximally exploit ROS-mediated cell death mechanisms as therapeutic anticancer strategy. In this regard, cold atmospheric plasma was combined with auranofin, a thioredoxin reductase inhibitor, in GBM (chapter 4). A synergistic effect was shown after this combination treatment in 2D and 3D, however, in 3D only high concentrations of auranofin synergized with plasma treatment. I confirmed a ROS-mediated response after combination treatment, which was able to induce distinct cell death mechanisms, specifically apoptosis and ferroptosis. Additionally, the auranofin and plasma combined treatment strategy induced cell death, which resulted in an increased release of DAMPs. Together with the observed DC maturation, these results indicates the potential increase in immunogenicity, though, the phagocytotic capacity of DCs was inhibited by auranofin. In chapter 5, I evaluated this promising oxidative stress combination therapy in GBM, in vivo. A decrease in tumor kinetics and an increased survival in GBM-bearing mice was observed when auranofin was sequentially combined with direct plasma treatment. No T cell infiltration was observed after auranofin monotherapy. However, further characterization of the TME after the combination therapy is necessary to provide more insight in the immunogenic effects in vivo. In conclusion, this PhD dissertation comprises novel and important therapeutic and immunogenic insights in cold atmospheric plasma and auranofin as promising oxidative stress-mediated treatment strategies for low immunogenic tumors, like PDAC and GBM. These preclinical results provide a solid basis for future research towards combinations with immunotherapeutic 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:181309 Serial 8643  
Permanent link to this record
 

 
Author Kaushik, N.K.; Bekeschus, S.; Tanaka, H.; Lin, A.; Choi, E.H. url  doi
openurl 
  Title Plasma medicine technologies Type (up) Editorial
  Year 2021 Publication Applied Sciences-Basel Abbreviated Journal Appl Sci-Basel  
  Volume 11 Issue 10 Pages 4584-4  
  Keywords Editorial; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract This Special Issue, entitled “Plasma Medicine Technologies”, covers the latest remarkable developments in the field of plasma bioscience and medicine. Plasma medicine is an interdisciplinary field that combines the principles of plasma physics, material science, bioscience, and medicine, towards the development of therapeutic strategies. A study on plasma medicine has yielded the development of new treatment opportunities in medical and dental sciences. An important aspect of this issue is the presentation of research underlying new therapeutic methods that are useful in medicine, dentistry, sterilization, and, in the current scenario, that challenge perspectives in biomedical sciences. This issue is focused on basic research on the characterization of the bioplasma sources applicable to living cells, especially to the human body, and fundamental research on the mutual interactions between bioplasma and organic–inorganic liquids, and bio or nanomaterials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000662527200001 Publication Date 2021-05-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2076-3417 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.679 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 1.679  
  Call Number UA @ admin @ c:irua:178139 Serial 6771  
Permanent link to this record
 

 
Author Barbiellini, B.; Kuriplach, J.; Saniz, R. url  doi
openurl 
  Title Study of rechargeable batteries using advanced spectroscopic and computational techniques Type (up) Editorial
  Year 2021 Publication Condensed Matter Abbreviated Journal  
  Volume 6 Issue 3 Pages 26  
  Keywords Editorial; Electron microscopy for materials research (EMAT)  
  Abstract Improving the efficiency and longevity of energy storage systems based on Li- and Na-ion rechargeable batteries presents a major challenge. The main problems are essentially capacity loss and limited cyclability. These effects are due to a hierarchy of factors spanning various length and time scales, interconnected in a complex manner. As a consequence, and in spite of several decades of research, a proper understanding of the ageing process has remained somewhat elusive. In recent years, however, combinations of advanced spectroscopy techniques and first-principles simulations have been applied with success to tackle this problem. In this Special Issue, we are pleased to present a selection of articles that, by precisely applying these methods, unravel key aspects of the reduction-oxidation reaction and intercalation processes. Furthermore, the approaches presented provide improvements to standard diagnostic and characterisation techniques, enabling the detection of possible Li-ion flow bottlenecks causing the degradation of capacity and cyclability.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000699368400001 Publication Date 2021-07-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2410-3896 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:181630 Serial 6890  
Permanent link to this record
 

 
Author Fatermans, J.; de Backer, A.; den Dekker, A.J.; Van Aert, S. pdf  doi
isbn  openurl
  Title Atom column detection Type (up) H2 Book chapter
  Year 2021 Publication Advances in imaging and electron physics T2 – Advances in imaging and electron physics Abbreviated Journal  
  Volume Issue Pages 177-214  
  Keywords H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract By combining statistical parameter estimation and model-order selection using a Bayesian framework, the maximum a posteriori (MAP) probability rule is proposed in this chapter as an objective and quantitative method to detect atom columns from high-resolution scanning transmission electron microscopy (HRSTEM) images. The validity and usefulness of this approach is demonstrated to both simulated and experimental annular dark-field (ADF) STEM images, but also to simultaneously acquired annular bright-field (ABF) and ADF STEM image data.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2021-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 217 Series Issue Edition  
  ISSN ISBN 978-0-12-824607-8; 1076-5670 Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes ERC Consolidator project funded by the European Union grant #770887 Picometrics Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:177531 Serial 6775  
Permanent link to this record
 

 
Author de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. pdf  doi
isbn  openurl
  Title Atom counting Type (up) H2 Book chapter
  Year 2021 Publication Advances in imaging and electron physics T2 – Advances in imaging and electron physics Abbreviated Journal  
  Volume Issue Pages 91-144  
  Keywords H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract In this chapter, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high-resolution annular dark-field (ADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. We show that this method can be applied to nanocrystals of arbitrary shape, size, and atom type. The validity of the atom-counting results is confirmed by means of detailed image simulations and it is shown that the high sensitivity of our method enables us to count atoms with single atom sensitivity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2021-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 217 Series Issue Edition  
  ISSN ISBN 978-0-12-824607-8; 1076-5670 Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes ERC Consolidator project funded by the European Union grant #770887 Picometrics Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:177529 Serial 6776  
Permanent link to this record
 

 
Author de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. pdf  doi
isbn  openurl
  Title Efficient fitting algorithm Type (up) H2 Book chapter
  Year 2021 Publication Advances in imaging and electron physics T2 – Advances in imaging and electron physics Abbreviated Journal  
  Volume Issue Pages 73-90  
  Keywords H2 Book chapter; Electron microscopy for materials research (EMAT)  
  Abstract An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic-resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighboring columns, enabling the analysis of a large field of view. To provide end-users with this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. In this chapter, this efficient algorithm is applied to three different nanostructures for which the analysis of a large field of view is required.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2021-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 217 Series Issue Edition  
  ISSN ISBN 978-0-12-824607-8; 1076-5670 Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes ERC Consolidator project funded by the European Union grant #770887 Picometrics Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:177528 Serial 6778  
Permanent link to this record
 

 
Author de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. pdf  doi
isbn  openurl
  Title General conclusions and future perspectives Type (up) H2 Book chapter
  Year 2021 Publication Advances in imaging and electron physics T2 – Advances in imaging and electron physics Abbreviated Journal  
  Volume Issue Pages 243-253  
  Keywords H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract This chapter provides an overview of statistical and quantitative methodologies that have pushed (scanning) transmission electron microscopy ((S)TEM) toward accurate and precise measurements of unknown structure parameters for understanding the relation between the structure of a material and its properties. Hereby, statistical parameter estimation theory has extensively been used which enabled not only measuring atomic column positions, but also quantifying the number of atoms, and detecting atomic columns as accurately and precisely as possible from experimental images. As a general conclusion, it can be stated that advanced statistical techniques are ideal tools to perform quantitative electron microscopy at the atomic scale. In the future, statistical methods will continue to be developed and novel quantification procedures will open up new possibilities for studying material structures at the atomic scale.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2021-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 217 Series Issue Edition  
  ISSN ISBN 978-0-12-824607-8; 1076-5670 Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes ERC Consolidator project funded by the European Union grant #770887 Picometrics Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:177533 Serial 6781  
Permanent link to this record
 

 
Author Fatermans, J.; de Backer, A.; den Dekker, A.J.; Van Aert, S. pdf  doi
isbn  openurl
  Title Image-quality evaluation and model selection with maximum a posteriori probability Type (up) H2 Book chapter
  Year 2021 Publication Advances in imaging and electron physics T2 – Advances in imaging and electron physics Abbreviated Journal  
  Volume Issue Pages 215-242  
  Keywords H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract The maximum a posteriori (MAP) probability rule for atom column detection can also be used as a tool to evaluate the relation between scanning transmission electron microscopy (STEM) image quality and atom detectability. In this chapter, a new image-quality measure is proposed that correlates well with atom detectability, namely the integrated contrast-to-noise ratio (ICNR). Furthermore, the working principle of the MAP probability rule is described in detail showing a close relation to the principles of model-selection methods.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2021-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 217 Series Issue Edition  
  ISSN ISBN 978-0-12-824607-8; 1076-5670 Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes ERC Consolidator project funded by the European Union grant #770887 Picometrics Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:177532 Serial 6782  
Permanent link to this record
 

 
Author de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. pdf  doi
isbn  openurl
  Title Introduction Type (up) H2 Book chapter
  Year 2021 Publication Advances in imaging and electron physics T2 – Advances in imaging and electron physics Abbreviated Journal  
  Volume Issue Pages 1-28  
  Keywords H2 Book chapter; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2021-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 217 Series Issue Edition  
  ISSN ISBN 978-0-12-824607-8; 1076-5670 Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes ERC Consolidator project funded by the European Union grant #770887 Picometrics Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:177525 Serial 6784  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: