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Author Van Tendeloo, M. openurl 
  Title Resource-efficient nitrogen removal from sewage : kinetic, physical and chemical tools for mainstream partial nitritation/anammox Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages iv, 204 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Adequate removal of pollutants from sewage is important to protect the environment and public health. Today, sewage treatment plants are operational in many parts of the world, and although the used technologies are effective in removing pollutants from wastewater, they are energy- and resource-intensive. Reshaping sewage treatment into a two-stage system, with separated organic carbon and nitrogen removal, facilitates the transformation towards energy-positive sewage treatment. This thesis will focus on resource-efficient nitrogen removal from sewage via partial nitritation/anammox (PN/A), with reduced organic carbon and oxygen consumption compared to conventional techniques. PN/A relies on the teamwork between two microbial groups to convert ammonium into nitrogen gas. Several other groups of microbes however can proliferate in the sludge, competing for substrate with the key players, lowering the nitrogen removal efficiency and increasing the energy demand. To obtain the desired microbial community, control tools should be applied to selectively promote the desired microbes while suppressing the unwanted competitors. In this thesis, multiple control tools were studied to establish a workable framework for successful implementation of PN/A in the main stream of a sewage treatment plant. These tools can be divided into three categories: i) kinetic tools, regulating substrate availability (e.g., oxygen availability control and residual ammonium concentration), ii) physical tools, revolving around sludge retention and selection (e.g., sludge age control and sludge aggregation form), and iii) chemical tools, exposing the sludge to stress conditions for which the unwanted microbes are vulnerable (e.g., sludge treatments with a single stressor such as free ammonia). The first research chapter focussed on oxygen availability control and single-stressor sludge treatments. The following two chapters covered the development of a novel multi-stressor concept combining substrate starvation and exposure to sulphide and free ammonia. In the final research chapter, the previously obtained knowledge was combined into a demonstration study on pilot-scale. The combination of these control tools was found effective in achieving nitrogen removal via PN/A, both on lab- and pilot-scale. Consequently, the obtained results in this thesis can catalyse the implementation of mainstream PN/A by providing a toolbox with multiple control tools and clever reactor design, thus advancing the concept of energy neutrality and resource efficiency in sewage treatment plants.  
  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:187665 Serial 7204  
Permanent link to this record
 

 
Author Cui, Z.; Zhou, C.; Jafarzadeh, A.; Meng, S.; Yi, Y.; Wang, Y.; Zhang, X.; Hao, Y.; Li, L.; Bogaerts, A. url  doi
openurl 
  Title SF₆ catalytic degradation in a γ-Al₂O₃ packed bed plasma system : a combined experimental and theoretical study Type A1 Journal article
  Year 2022 Publication High voltage Abbreviated Journal  
  Volume (down) Issue Pages 1-11  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Effective abatement of the greenhouse gas sulphur hexafluoride (SF6) waste is of great importance for the environment protection. This work investigates the size effect and the surface properties of gamma-Al2O3 pellets on SF6 degradation in a packed bed dielectric barrier discharge (PB-DBD) system. Experimental results show that decreasing the packing size improves the filamentary discharges and promotes the ignition and the maintenance of plasma, enhancing the degradation performance at low input powers. However, too small packing pellets decrease the gas residence time and reduce the degradation efficiency, especially for the input power beyond 80 W. Besides, lowering the packing size promotes the generation of SO2, while reduces the yields of S-O-F products, corresponding to a better degradation. After the discharge, the pellet surface becomes smoother with the appearance of S and F elements. Density functional theory calculations show that SF6 is likely to be adsorbed at the Al-III site over the gamma-Al2O3(110) surface, and it is much more easily to decompose than in the gas phase. The fluorine gaseous products can decompose and stably adsorb on the pellet surface to change the surface element composition. This work provides a better understanding of SF6 degradation in a PB-DBD system.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000827312700001 Publication Date 2022-07-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2397-7264 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 4.4 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.4  
  Call Number UA @ admin @ c:irua:189603 Serial 7208  
Permanent link to this record
 

 
Author Pacquets, L. url  openurl
  Title Towards stable Cu-Ag bimetallic nanoparticles to boost the electrocatalytic CO2 reduction Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages xvi, 188 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)  
  Abstract Ever since the industrial revolution, the emission of greenhouse gasses dramatically increased, resulting in high CO2 concentration in the atmosphere. The electrochemical conversion of CO2 to value added products, such as carbon monoxide, formic acid, methane, ethylene and ethanol is a very promising strategy to inhibit CO2 emissions. Nevertheless, at the moment, the electrochemical CO2 reduction (eCO2R) is not yet industrially viable, mainly due to the lack of good electrocatalysts. On the other hand, core-shell nanoparticles (NPs) have emerged over the last couple of years as promising candidates. It is believed that bimetallic enhancement effects are behind the improved performance of these core-shell NPs when compared to the individual metals. Although widely investigated, there are still some remaining issues and/or open questions. Indeed, the development of a robust and straightforward synthesis method along with fundamental insight into their resistance towards electrochemical stress remains absent. A good control over morphology, size and composition is key in determining which properties are beneficial for the eCO2R. Since these catalysts are designed to be implemented in electrolyzers, they have to maintain long-term performance. This makes the design of a reproducible method, unveiling structure-performance relationships the effect of electrochemical stress, a crucial aspect. Exploring and modifying existing synthesis methods, have led to the acquisition of a robust and reproducible synthesis method where thermal decomposition of the Cu core is combined with the galvanic replacement of Ag in organic solvents. The implementation of this method has led to the design of a wide variety of Cu-Ag bimetallic NPs and enabled to investigate their composition-selectivity profile. Introducing Ag on Cu suppressed hydrogen and increased the CO formation. CO production was boosted by using Cu@Ag core-shells and was promoted even more by changing the type of electrolyte. As these nanoparticles suffered from degradation, the 3D mapping of the structural changes of Cu@Ag core-shells under operating conditions led to the hypothesis of a two-step degradation mechanism where initially Cu leaching was observed with the subsequent sintering of the Ag shells. One approach to avoid this electrochemical degradation, investigated in this research, was the application of an ultrathin carbon layer to protect the active layer. This ultrathin carbon layer operated as a protective layer, suppressing hydrogen production and increasing the stability of the electrocatalyst. In conclusion, the product selectivity can be tuned by using different Cu-Ag bimetallic nanoparticles synthesized through a robust method. Their unique degradation pathway of Cu@Ag core-shell nanoparticles has led to the proposition of a more accurate stabilization strategy. These findings can contribute significantly in the quest for improved electrocatalysts for the eCO2R.  
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  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:190236 Serial 7221  
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Author Gielis, J.; Shi, P.; Caratelli, D. openurl 
  Title Universal equations : a fresh perspective Type A1 Journal article
  Year 2022 Publication Growth and Form Abbreviated Journal  
  Volume (down) Issue Pages  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract A uniform description of natural shapes and phenomena is an important goal in science. Such description should check some basic principles, related to 1) the complexity of the model, 2) how well its fits real objects, phenomena and data, and 3) ia direct connection with optimization principles and the calculus of variations. In this article, we present nine principles, three for each group, and we compare some models with a claim to universality. It is also shown that Gielis Transformations and power laws have a common origin in conic sections  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:189317 Serial 7224  
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Author Magalhães Cunha, S. url  openurl
  Title Wave-packet dynamics and electronic transport properties in 2D materials Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages 219 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract This piece of work is twofold. First, the time evolution of wave-packets in 2D systems is analyzed by the Split-Operator technique in three different scenarios: in multilayer phosphorene, the transient oscillations in the time-dependent average of position and momentum were observed due to the zitterbewegung effect, and the wave packet propagates non-uniformly along the space deforming itself into an elliptical shape. These results were corroborated by the Green’s function formalism except for large values of the wave-vector and long times; in 2D semiconductor quantum wires (QWs) with anisotropic effective masses and different angle orientations with respect to the anisotropic axis. We have shown that the greater this angle, the smaller is the energy levels spacing implying in an increase of the accessible electronic states. Additionally, for non-null magnetic field, the quantum Hall edge states are significantly affected by the edge orientation. In the anisotropic case damped oscillations in the average values of velocity in both x and y directions where obtained. Theses oscillations are originated by the QW geometry but also from subwavepackets with different momentum orientations, whereas for isotropic QWs the wavepacket disperses without splitting; in the third scenario the split-operator technique was used to study the Landau levels, the wave packet trajectories and velocities of electrons in graphene at low-energy regime described by a modified Dirac equation where the momentum-operator is written in a generalized form as result of applying the position-dependent translation operator formalism (PDTO). In the second part of this thesis, the electronic and tunneling properties of α − T3 lattices were studied. Electrons in these lattices behave analogous to integer-spin Dirac Fermions. The presence of a third atomic site in the unit cell leads to a flat band in the energy spectrum, providing unique electronic and tunneling properties. The presence of a super-periodic potential and the inclusion of symmetry-breaking terms results in deviations of the atomic equivalence between the atomic sites affecting the Dirac points and the band-gap. Small deviations in the equivalence between the atomic sites and the number of barriers change the transmission properties in these lattices. Additionally, new tunneling regions are possible by adjusting the symmetry between the atomic sites and affect the omnidirectional total transmission called super-Klein tunneling observed in these lattices. We compare those results to the tunneling probabilities through regions where the energy spectrum changes from linear with a middle flat band to a hyperbolic dispersion.  
  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:189191 Serial 7227  
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Author Batuk, M.; Vandemeulebroucke, D.; Ceretti, M.; Paulus, W.; Hadermann, J. url  doi
openurl 
  Title Topotactic redox cycling in SrFeO2.5+δ explored by 3D electron diffraction in different gas atmospheres Type A1 Journal article
  Year 2022 Publication Journal of materials chemistry A : materials for energy and sustainability Abbreviated Journal J Mater Chem A  
  Volume (down) Issue Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract For oxygen conducting materials applied in solid oxide fuel cells and chemical-looping processes, the understanding of the oxygen diffusion mechanism and the materials’ crystal structure at different stages of the redox reactions is a key parameter to control their performance. In this paper we report the first ever in situ 3D ED experiment in a gas environment and with it uncover the structure evolution of SrFeO2.5 as notably different from that reported from in situ X-ray and in situ neutron powder diffraction studies in gas environments. Using in situ 3D ED on submicron sized single crystals obtained from a high quality monodomain SrFeO2.5 single crystal , we observe the transformation under O2 flow of SrFeO2.5 with an intra- and interlayer ordering of the left and right twisted (FeO4) tetrahedral chains (space group Pcmb) into consecutively SrFeO2.75 with space group Cmmm (at 350°C, 33% O2) and SrFeO3-δ with space group Pm3 ̅m (at 400°C, 100% O2). Upon reduction in H2 flow, the crystals return to the brownmillerite structure with intralayer order, but without regaining the interlayer order of the pristine crystals. Therefore, redox cycling of SrFeO2.5 crystals in O2 and H2 introduces stacking faults into the structure, resulting in an I2/m(0βγ)0s symmetry with variable β.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000891928400001 Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2050-7488 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.9 Times cited Open Access OpenAccess  
  Notes Financial support is acknowledged from the FWO-Hercules fund I003218N ‘Infrastructure for imaging nanoscale processes in gas/vapor or liquid environments’, from the University of Antwerp through grant BOF TOP 38689. This work was supported by the European Commission Horizon 2020 NanED grant number 956099. Financial support from the French National Research Agency (ANR) through the project “Structural induced Electronic Complexity controlled by low temperature Topotactic Reaction” (SECTOR No. ANR-14-CE36- 0006-01) is gratefully acknowledged. Approved Most recent IF: 11.9  
  Call Number EMAT @ emat @c:irua:192325 Serial 7229  
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Author Wang, J.; Zhang, K.; Kavak, S.; Bals, S.; Meynen, V. pdf  url
doi  openurl
  Title Modifying the Stöber Process: Is the Organic Solvent Indispensable? Type A1 Journal Article
  Year 2022 Publication Chemistry-A European Journal Abbreviated Journal Chem-Eur J  
  Volume (down) Issue Pages  
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;  
  Abstract The Stöber method is one of the most important and fundamental processes for the synthesis of inorganic (nano)materials but has the drawback of using a large amount of organic solvent. Herein, ethanol was used as an example to explore if the organic solvent in a typical Stöber method can be omitted. It was found that ethanol increases the particle size of the obtained silica spheres and aids the formation of uniform silica particles rather than forming a gel. Nevertheless, the results indicated that an organic solvent in the initial synthesis mixture is not indispensable. An initially immiscible synthesis method was discovered, which can replace the organic solvent-based Stöber method to successfully synthesize silica particles with the same size ranges as the original Stöber process without addition of organic solvents. Moreover, this process can be of further value for the extension to synthesis processes of other materials based on the Stöber process.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000898283500001 Publication Date 2022-12-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0947-6539 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.3 Times cited 3 Open Access OpenAccess  
  Notes The authors are grateful to Alexander Vansant and Dr. Steven Mullens of VITO for their contributions to the DLS measurements in this paper. J.W acknowledges the State Scholarship funded by the China Scholarship Council (201806060123). K.Z acknowledges the EASiCHEM project funded by the Flemish Strategic Basic Research Program of the Catalisti cluster and Flanders Innovation & Entrepreneurship (HBC.2018.0484). S.K acknowledges the Flemish Fund for Scientific Research (FWO Flanders) through a PhD research grant (1181122N). Approved Most recent IF: 4.3  
  Call Number EMAT @ emat @c:irua:191646 Serial 7233  
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Author Le Compte, M.; Cardenas De La Hoz, E.; Peeters, S.; Smits, E.; Lardon, F.; Roeyen, G.; Vanlanduit, S.; Prenen, H.; Peeters, M.; Lin, A.; Deben, C. url  doi
openurl 
  Title Multiparametric tumor organoid drug screening using widefield live-cell imaging for bulk and single-organoid analysis Type A1 Journal article
  Year 2022 Publication Jove-Journal Of Visualized Experiments Abbreviated Journal Jove-J Vis Exp  
  Volume (down) Issue 190 Pages 1-18  
  Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Center for Oncological Research (CORE)  
  Abstract Patient-derived tumor organoids (PDTOs) hold great promise for preclinical and translational research and predicting the patient therapy response from ex vivo drug screenings. However, current adenosine triphosphate (ATP)-based drug screening assays do not capture the complexity of a drug response (cytostatic or cytotoxic) and intratumor heterogeneity that has been shown to be retained in PDTOs due to a bulk readout. Live-cell imaging is a powerful tool to overcome this issue and visualize drug responses more in-depth. However, image analysis software is often not adapted to the three-dimensionality of PDTOs, requires fluorescent viability dyes, or is not compatible with a 384-well microplate format. This paper describes a semi-automated methodology to seed, treat, and image PDTOs in a high-throughput, 384-well format using conventional, widefield, live-cell imaging systems. In addition, we developed viability marker-free image analysis software to quantify growth rate-based drug response metrics that improve reproducibility and correct growth rate variations between different PDTO lines. Using the normalized drug response metric, which scores drug response based on the growth rate normalized to a positive and negative control condition, and a fluorescent cell death dye, cytotoxic and cytostatic drug responses can be easily distinguished, profoundly improving the classification of responders and non-responders. In addition, drug-response heterogeneity can by quantified from single-organoid drug response analysis to identify potential, resistant clones. Ultimately, this method aims to improve the prediction of clinical therapy response by capturing a multiparametric drug response signature, which includes kinetic growth arrest and cell death quantification. ,  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000928020400010 Publication Date 2022-12-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1940-087x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.2 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 1.2  
  Call Number UA @ admin @ c:irua:193168 Serial 7271  
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Author Deben, C.; Cardenas De La Hoz, E.; Le Compte, M.; Van Schil, P.; Hendriks, J.M.H.; Lauwers, P.; Yogeswaran, S.K.; Lardon, F.; Pauwels, P.; van Laere, S.; Bogaerts, A.; Smits, E.; Vanlanduit, S.; Lin, A. url  doi
openurl 
  Title OrBITS : label-free and time-lapse monitoring of patient derived organoids for advanced drug screening Type A1 Journal article
  Year 2022 Publication Cellular Oncology (2211-3428) Abbreviated Journal Cell Oncol  
  Volume (down) Issue Pages 1-16  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Center for Oncological Research (CORE)  
  Abstract Background Patient-derived organoids are invaluable for fundamental and translational cancer research and holds great promise for personalized medicine. However, the shortage of available analysis methods, which are often single-time point, severely impede the potential and routine use of organoids for basic research, clinical practise, and pharmaceutical and industrial applications. Methods Here, we developed a high-throughput compatible and automated live-cell image analysis software that allows for kinetic monitoring of organoids, named Organoid Brightfield Identification-based Therapy Screening (OrBITS), by combining computer vision with a convolutional network machine learning approach. The OrBITS deep learning analysis approach was validated against current standard assays for kinetic imaging and automated analysis of organoids. A drug screen of standard-of-care lung and pancreatic cancer treatments was also performed with the OrBITS platform and compared to the gold standard, CellTiter-Glo 3D assay. Finally, the optimal parameters and drug response metrics were identified to improve patient stratification. Results OrBITS allowed for the detection and tracking of organoids in routine extracellular matrix domes, advanced Gri3D (R)-96 well plates, and high-throughput 384-well microplates, solely based on brightfield imaging. The obtained organoid Count, Mean Area, and Total Area had a strong correlation with the nuclear staining, Hoechst, following pairwise comparison over a broad range of sizes. By incorporating a fluorescent cell death marker, infra-well normalization for organoid death could be achieved, which was tested with a 10-point titration of cisplatin and validated against the current gold standard ATP-assay, CellTiter-Glo 3D. Using this approach with OrBITS, screening of chemotherapeutics and targeted therapies revealed further insight into the mechanistic action of the drugs, a feature not achievable with the CellTiter-Glo 3D assay. Finally, we advise the use of the growth rate-based normalised drug response metric to improve accuracy and consistency of organoid drug response quantification. Conclusion Our findings validate that OrBITS, as a scalable, automated live-cell image analysis software, would facilitate the use of patient-derived organoids for drug development and therapy screening. The developed wet-lab workflow and software also has broad application potential, from providing a launching point for further brightfield-based assay development to be used for fundamental research, to guiding clinical decisions for personalized medicine.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000898426100001 Publication Date 2022-12-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2211-3428; 2211-3436 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.6 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 6.6  
  Call Number UA @ admin @ c:irua:192698 Serial 7272  
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Author Wang, J. url  openurl
  Title Plasma catalysis : study of CO2 reforming of CH4 in a DBD reactor Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages XVI, 232 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The plasma-based dry reforming in a dielectric barrier discharge (DBD) reactor is important to achieve sustainable goals, but many challenges remain. For example, the conversion and energy yield of DBD reactors are relatively low, and the catalysts or packing materials used in existing studies cannot improve them, possibly due to the unsuitable properties and structures of catalysts or packing materials for plasma processes. In order to study the effect of catalyst structure on plasma-based dry reforming, a controllable synthesis of the catalyst supports or templates was explored. In Chapter 2, an initially immiscible synthesis method was proposed to synthesize uniform silica spheres, which can replace the organic solvent-based Stöber method to successfully synthesize silica particles with the same size ranges as the original Stöber process without addition of organic solvents. Using the silica spheres as templates, 3D porous Cu and CuO catalysts with different pore sizes were synthesized in Chapter 3 to study the effect of catalyst pore size on the plasma-catalytic dry reforming. In most cases, the smaller the pore size, the higher the conversion of CH4 and CO2 due to the reaction of radicals and ions formed in the plasma. An exception are the samples synthesized from 1 μm silica, which show better performance due to the electric field enhancement for pore sizes close to the Debye length. Besides the pore size, the particle diameter of the catalyst or packing is also one of the important factors affecting the interaction between plasma and catalyst. In Chapter 4, SiO2 spheres (with or without supported metal) were used to study the effect of different support particle sizes on plasma-based dry reforming. We found that a uniform SiO2 packing improves the conversion of plasma-based dry reforming. The conversion of plasma-based dry reforming first increases and then decreases with increasing particle size, due to the balance between the promoting and hindering effect of the particle filling on the plasma discharge. Chapter 5 is to improve the design of the DBD reactor itself, in order to try to increase its low energy yield. Some stainless steel rings were put over the inner electrode rod of the DBD reactor. The presence of rings increases the local electric field, the displaced charges and the discharge fraction, and also makes the discharge more stable and with more uniform intensity. The placement of the rings improves the performance of the reactor at 30 W supplied power.  
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  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:194045 Serial 7273  
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Author Penders, A.G. url  openurl
  Title Microstructural investigation of irradiation assisted stress corrosion cracking mechanisms based on focused ion beam analysis of tested and industrial specimens Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages xxxviii, 226 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Irradiation assisted stress corrosion cracking (IASCC) is an intergranular cracking effect which can occur in heavily irradiated internal structural components of nuclear reactor cores. It is a complex phenomenon which is not yet fully understood because it occurs through an interplay of several material degradation processes. The factors that influence IASCC susceptibility include irradiation damage (neutrons and other irradiation particles stemming from the nuclear fission reaction), the operating temperature of the nuclear reactor, water corrosion, operating stresses, and the composition of materials susceptible to IASCC. Such materials are typically fabricated from austenitic stainless steels because of their relatively high strength, ductility, and fracture toughness. However, besides excellent metallurgical and corrosion resistant qualities, the operating conditions may still cause severe material degradation and component failure, which is extremely important for nuclear power plant safety and lifetime managements. Despite much accumulated data in the literature, both crack initiation and crack propagation mechanisms still need to be further elucidated. To that end, a probabilistic fracture model entitled the subcritical crack propagation (SCP) was recently developed, which assumes that the oxidized part of stainless steel in front of the crack plays an essential role in the crack initiation and crack propagation in sample failures. Still, despite a very good agreement with experimental observations, the SCP model but also other contemporary models favoured within the literature, require further experimental verification to what concerns the investigation of (IA)SCC. To that end, the main objective of this doctorate was to utilize experimental instrumentations like SEM, FIB-SEM and (S)TEM to conduct the investigation of the crack initiation and propagation processes in both tested and industrial specimens. Some of the investigated materials were retrieved within a nuclear reactor and are thus considered as unique test material to investigate the material degradation processes relevant for cracking. Other specimens were tailor-made to simulate the cracking processes of irradiated materials in otherwise un-irradiated materials. The newly acquired experimental results in this doctorate help rationalize existing models and methodologies used in the literature to analyse the IASCC failures of structural materials of reactor components. These results also facilitate in the development of predictive methodologies and mitigation strategies towards IASCC cracking and provide more information on IASCC from a microstructural perspective.  
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  Corporate Author Thesis  
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  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
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  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:192431 Serial 7323  
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Author Han, S.; Tang, C.S.; Li, L.; Liu, Y.; Liu, H.; Gou, J.; Wu, J.; Zhou, D.; Yang, P.; Diao, C.; Ji, J.; Bao, J.; Zhang, L.; Zhao, M.; Milošević, M.V.; Guo, Y.; Tian, L.; Breese, M.B.H.; Cao, G.; Cai, C.; Wee, A.T.S.; Yin, X. pdf  url
doi  openurl
  Title Orbital-hybridization-driven charge density wave transition in CsV₃Sb₅ kagome superconductor Type A1 Journal article
  Year 2022 Publication Advanced materials Abbreviated Journal Adv Mater  
  Volume (down) Issue Pages 1-9  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Owing to its inherent non-trivial geometry, the unique structural motif of the recently discovered kagome topological superconductor AV(3)Sb(5) (A = K, Rb, Cs) is an ideal host of diverse topologically non-trivial phenomena, including giant anomalous Hall conductivity, topological charge order, charge density wave (CDW), and unconventional superconductivity. Despite possessing a normal-state CDW order in the form of topological chiral charge order and diverse superconducting gaps structures, it remains unclear how fundamental atomic-level properties and many-body effects including Fermi surface nesting, electron-phonon coupling, and orbital hybridization contribute to these symmetry-breaking phenomena. Here, the direct participation of the V3d-Sb5p orbital hybridization in mediating the CDW phase transition in CsV3Sb5 is reported. The combination of temperature-dependent X-ray absorption and first-principles studies clearly indicates the inverse Star-of-David structure as the preferred reconstruction in the low-temperature CDW phase. The results highlight the critical role that Sb orbitals play and establish orbital hybridization as the direct mediator of the CDW states and structural transition dynamics in kagome unconventional superconductors. This is a significant step toward the fundamental understanding and control of the emerging correlated phases from the kagome lattice through the orbital interactions and provides promising approaches to novel regimes in unconventional orders and topology.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000903664200001 Publication Date 2022-12-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 29.4 Times cited 1 Open Access OpenAccess  
  Notes Approved Most recent IF: 29.4  
  Call Number UA @ admin @ c:irua:193500 Serial 7328  
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Author Kashiwar, A. url  doi
openurl 
  Title TEM investigations of deformation mechanisms in nanocrystalline metals and multilayered composites Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages xvi, 129 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract In the last few decades, nanostructuring has driven significant attention towards the development of novel metallic materials with advanced mechanical properties. Nanocrystalline (nc) metals are a class of nanostructured materials with grain sizes smaller than about 100 nm. These exhibit outstanding mechanical strength and fatigue properties compared to their coarse-grained (cg) counterparts. These are promising candidates for application as structural or functional materials. Nc metals in the form of thin films are employed as hard coatings on bulk components, structural components, and conductive layers in various micro-/nanoscale devices. These structural components and devices are often subjected to cyclic stresses or fatigue loading. Under these cyclic stresses, nc metals tend to exhibit the Bauschinger effect (BE). The strength loss during the BE is of great importance concerning the strength-ductility trade-off in nc metals. Furthermore, contact surfaces of the engineering components in service often undergo relative motion and are subject to both friction and wear. These extreme loading conditions demand nc metals with tailored interfacial characteristics for improved tribological performance. Aiming at ensuring high reliability and mechanical robustness for optimum performance of these components, there has been a strong motivation for understanding the mechanical properties and governing deformation mechanisms in nc metallic materials. This thesis aimed at in-depth investigation of microstructures at micro-/nanoscales using state-of-the-art in situ and ex situ transmission electron microscopy (TEM) to develop a closer link between the deformation structure and underlying deformation mechanisms in some nc metallic materials. The thesis has primarily focused on the in situ TEM nanomechanics of the BE and rotational deformation of grains in nc palladium thin films. A sputtered thin film of nc Pd was deformed inside TEM by cyclic loading-unloading experiments and the evolving microstructure was studied in real-time under different TEM imaging modes. The stress-strain response of the film exhibited a characteristic non-linear unloading behavior confirming the BE in the film. The corresponding bright-field TEM imaging revealed evidence of partially reversible dislocation activity. Towards a quantitative understanding of the deformation structure in real-time, in situ nanomechanical testing was coupled with precession-assisted automated crystal orientation mapping in scanning TEM (ACOM-STEM). Global ACOM-STEM analysis offered crystal orientation of a large number of grains at different states of deformation and confirmed partially reversible rotations of nanosized grains fitting to the observed BE during loading and unloading. Analysis of intragranular rotations showed substantial changes in the sub-structure within most of these grains indicating a dominant role of dislocation-based processes in driving these rotations. Globally, an unusually random evolution of texture was seen that demonstrated the influence of deformation heterogeneity and grain interactions on the resulting texture characteristics in nc metals. In the quest of understanding the grain interactions, local investigations based on annular dark-field STEM imaging during loading-unloading showed reversible changes in the contrast of grains with sets of adjoining grains exhibiting a unique cooperative rotation. Local analysis of the density of geometrically necessary dislocations (GNDs) showed the formation of dislocation pile-up at grain boundaries due to the generation of back-stresses during unloading. Critical observations of the evolution of GND density offered greater insights into the mechanism of cooperative grain rotations and these rotations were related to grain structure and grain boundary characteristics. In addition to understanding the influence of grain structure and grain boundaries, the thesis has further investigated the role of heterointerfaces in sputtered Au-Cu and Cu-Cr nanocrystalline multilayered composites (NMCs) deformed under cyclic sliding contact. The microstructural evolution in the NMCs was investigated at different deformation states by classical TEM imaging, ACOM-STEM as well as energy-filtered TEM (EFTEM). Au-Cu NMC with an initial high density of twin boundaries deformed by stress-driven detwinning with a concurrent change in grain structure in both Au and Cu. The formation of a vortex structure was observed due to plastic flow instabilities at Au-Cu interfaces that led to codeformation and mechanical intermixing. Cu-Cr NMC showed a preferential grain growth in Cu layers whereas no noticeable change in the grain sizes was seen in Cr layers. The phase maps revealed sharp interfaces between Cu and Cr layers indicating no intermixing between the immiscible phases. EFTEM results exposed the cracking processes in Cr layers with a concurrent migration of Cu in the cracks. Overall, the thesis has attempted to analyze the competing deformation processes and relate these with the microstructural heterogeneity in terms of grain structure and GB and interfacial characteristics in nc metallic materials.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:189013 Serial 7343  
Permanent link to this record
 

 
Author Motamedi, J.; Azadi, H.; Alijanpour, A.; Shafiei, A.B.; Sheidai-Karkaj, E.; Mofidi-Chelan, M.; Moghaddam, S.M.; Van Passel, S.; Witlox, F. pdf  doi
openurl 
  Title Economic indices of by-products utilization and forage production in semi-arid rangelands Type A1 Journal article
  Year 2022 Publication Journal Of Environmental Planning And Management Abbreviated Journal J Environ Plann Man  
  Volume (down) Issue Pages 1-29  
  Keywords A1 Journal article; Sociology; Law; Engineering Management (ENM)  
  Abstract One of the most basic criteria in documenting rangeland use prospects is the recognition of byproducts and their economic appraisal. The current study was conducted to assess the economic indices of exploiting byproduct production in Shahindej, Northwest Iran. For this purpose, 24 by-product-generating species were selected in 114 locations that belong to 49 rangeland units. The total expected value of 24 by-product generating species yield and forage production was calculated at 44.22 USD ha(-1). The results of this study showed that the sustainability of natural resources depends on the effective participation and empowerment of local communities. Furthermore, by-product exploitation contributes significantly to the local economy and employment while also reducing grazing intensity. Overall, the findings of this study show that by-product earnings should be considered in range management schemes and comprehensive natural-area management.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000830614200001 Publication Date 2022-07-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0964-0568 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 1.56 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:189725 Serial 7355  
Permanent link to this record
 

 
Author Naderi Mahdei, K.; Esfahani, S.M.J.; Lebailly, P.; Dogot, T.; Van Passel, S.; Azadi, H. pdf  doi
openurl 
  Title Environmental impact assessment and efficiency of cotton : the case of Northeast Iran Type A1 Journal article
  Year 2022 Publication Environment, development and sustainability Abbreviated Journal  
  Volume (down) Issue Pages 1-21  
  Keywords A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM)  
  Abstract Cotton is one of the important crops that play an important role in creating a livelihood for rural people in many parts of Iran. Cotton production necessitates a large amount of resources (e.g., fossil energy and agrochemicals, all of which have the potential to damage the environment in various ways). The purpose of the current study was to evaluate the environmental effects of cotton production in the South Khorasan Province of Iran. For this purpose, life cycle assessment (LCA) and data envelopment analysis (DEA) techniques have been applied to investigate the environmental impacts of cotton production. LCA is a practical method to evaluate the environment on the product flow, in which all aspects of the product life cycle are examined by a comprehensive approach. Furthermore, combining the LCA method with other managerial strategies such as DEA could allow researchers to provide decision-makers with more practical and interpretable data. The findings of the efficiency test showed that the average technical efficiency, pure technical efficiency, and scale efficiency were 0.81, 0.92, and 0.87, respectively. Respiratory inorganics (i.e., respiratory effects resulting from winter smog caused by emissions of dust, sulfur, and nitrogen oxides to air) posed the greatest environmental burden in cotton production, followed by non-renewable energy, carcinogens, and global warming. In addition, the highest effects were on human health, and then, on resources and climate change. Energy, on-system pollution, and waste played a crucial role in the environmental impacts of cotton processing. This study suggests improving farmers' knowledge toward the optimum application of chemical fertilizers, or their substitution with green fertilizers, which reduces the environmental effect of growing cotton in the area.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000826851400001 Publication Date 2022-07-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1387-585x; 1573-2975 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 4.9 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.9  
  Call Number UA @ admin @ c:irua:189630 Serial 7356  
Permanent link to this record
 

 
Author Larraín, M. openurl 
  Title Recycling of plastics : linking technical, economic and policy aspects of post-consumer plastic packaging Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages x, 165 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Engineering Management (ENM); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS)  
  Abstract The rise in plastic packaging production and disposal has encouraged the progress of recycling technologies and aroused policy discussion on how to increase recycling rates. However, the effect that these policy instruments will have on the development of the different recycling technologies has not been studied holistically yet. This dissertation explores how new and existing technologies will behave under the market and policy conditions observed at present and after the implementation of the policy instruments that are under discussion. The technologies that are analyzed in this thesis are mechanical recycling and thermochemical recycling of post-consumer polyolefin waste. Using a techno-economic assessment that takes into account the physical properties of the different plastic fractions and their contamination level, the study shows that both mechanical and thermochemical recycling can be profitable if oil prices remain steady or increase. Specifically, mechanical recycling will show better results than thermochemical recycling for plastic fractions with low contamination levels. On the contrary, thermochemical recycling is more profitable for fractions with a higher contamination level from which high-quality products cannot be obtained with mechanical recycling, such as PE films. Moreover, it demonstrates that besides the oil prices and sorted waste prices, waste purity and the plant capacity are the variables that influence more the net present value of thermochemical recycling and the labor cost and waste purity the ones of mechanical recycling. The thesis explores the dynamics between the stakeholders of the circular value chain and predicts the recycling rates under the implementation of several policy instruments. This is done with a supply chain equilibrium model, based on the extended producer responsibility scheme implemented in Flanders, that uses as an input the cost structures of mechanical and thermochemical recycling obtained from the techno-economic assessments. Direct interventions like recycled content standards, can decouple the recycling industry from the oil market, but in the long term, they may not present incentives to achieve recycling levels beyond the targeted amounts and thus limit technological innovation. On the contrary, economic interventions such as taxes, create economic incentives for recycling and allow fund collection from the government but leave the recycled levels dependent on external markets. Results also show that higher recycling rates does not necessarily mean better environmental performance. Therefore, when designing circular economy policies, policymakers should carefully analyze whether the intention is to increase circularity or improve the sustainability of the value chains.  
  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:191730 Serial 7366  
Permanent link to this record
 

 
Author Tschulkow, M. openurl 
  Title A techno-environmental economic assessment of a lignin-first biorefinery : a dynamic and prospective framework for emerging technologies Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages 175 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Engineering Management (ENM)  
  Abstract Novel emerging biorefinery technologies have gained interest and have the potential to tackle several sustainability challenges in our society. A lignin-first biorefinery process – reductive catalytic fractionation (RCF) – is currently under development with the aim to process wood into high-value end-products that replace highly polluting fossil oil-based products. However, such emerging technologies are not matured yet, holding a certain degree of technological, economic, and environmental uncertainty. Hence, an appropriate assessment method is required to assess techno-economic feasibility and environmental impacts of emerging uncertain technologies (e.g lignin-first RCF process). This dissertation aims to develop an integrated techno-environmental economic assessment framework to assess emerging technologies dynamically and prospectively from economic and environmental points of view. First, a techno-economic assessment (TEA) is performed to assess the economic feasibility and the most influential economic and technological parameters of the lignin-first RCF biorefinery taking the whole wood value chain into account. By making the relations across the wood value chain, the scale of the biorefinery, wood species, and output prices highly determine the economic feasibility. The economic feasibility can be reached by a sufficient capacity level which depends on wood species-specific conditions. Also, waste wood proves to be the most profitable feedstock in comparison to virgin wood. Second, an analytical real options analysis (ROA) is performed taking two correlated market uncertainties and the value of flexibility into account to identify the optimal investment decision in an RCF biorefinery. Two different investment options, separated and united investments in harvesting equipment and RCF biorefinery, are analyzed. In both scenarios, market uncertainty postpones the investment. When both investment decisions are united, the probability of investment increases in comparison to separated investments. The study reveals that RCF has the potential to stimulate investments within the wood value chain. Third, a consequential life cycle assessment (LCA) is performed to assess the carbon emissions and the environmental consequences of the lignin-first RCF process and its products. The study reveals that at the current stage RCF products have higher carbon emissions than their alternative counterparts. Several options to improve the environmental performance are discussed such as different RCF technology configurations, targeting different RCF products with the ability to replace higher polluting alternative counterparts on the markets. Other discussion points such as transportation type and the distance, (in-)direct land-use change, the use stage and disposal stages implications, and a more comprehensive environmental view of the RCF products, show the potential to improve the environmental performance of the RCF technology. Overall, the study shows that the RCF process can be environmentally desirable if the appropriate RCF configuration and products are chosen. Finally, the above-mentioned methods – techno-economic assessment, analytical real options analysis, and consequential life cycle assessment – are uniquely integrated within the newly developed integrated assessment framework. The framework has the aim to complement the shortcomings and combine the advantages of all three methods. The framework assesses emerging technologies to give predictive insights about the time-specific economic and environmental performance under the newly developed three threshold conditions: technological readiness, economic feasibility, and environmental desirability. The developed integrated assessment framework assesses dynamically and prospectively the RCF biorefinery implementation under Belgian conditions. It reveals that the economic feasibility increases and carbon emissions decrease over time. The RCF biorefinery fulfills all three threshold conditions – technological readiness, economic feasibility, and environmental desirability – consecutively. The newly developed integrated assessment framework offers decision support to several stakeholders of emerging technologies starting from low technology readiness level (TRL). Practitioners such as the technology developers, researchers, and policymakers can use the framework to evaluate emerging technologies that deal with high levels of technological, economic, and environmental uncertainties. The framework assesses emerging technologies on a detailed level to give decision-makers in-depth insights into the intertwined nature of the technological, economic, and environmental dimensions. It offers insights into the expected time-specific economic and environmental performances, potential, and challenges of the emerging technology to further improve the technology and direct R&Ds along the right path.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:188968 Serial 7369  
Permanent link to this record
 

 
Author Mendonça Verbinnen, C.D. openurl 
  Title Development of semiconductor-based photoelectrochemical sensing strategies for phenolic compounds in natural and supply water Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages 152 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)  
  Abstract A wide variety of organic and inorganic compounds have been frequently released into the environment without control by industries and agricultural activities. This has caused significant impact on the development and health of living organisms, and biodiversity. Therefore, the challenge of monitoring and/or remediation of these contaminants remains. This thesis presents the development of three sensing strategies based on photoelectrochemical sensors to monitor phenolic contaminants. The well-known semiconductors TiO2 and ZnO were used for building novel setups for nM analysis of phenolic compounds in water. The setups employing TiO2-based photosensors were integrated into a photoelectrochemical flow cell. The flow system favored higher sensitivity of the method by periodic wash sequences of the electrode, significantly reducing the electrode fouling. Firstly, a straightforward method was developed based on the immobilization of TiO2 on screen printed graphite electrodes. Under UV light, the developed photosensor presented high performance for the detection of 4- aminophenol. A second study was developed by impregnating gold nanoparticles into TiO2 structure. The incorporation of gold nanoparticles can broaden the light absorption region of TiO2 and improve its photocatalytic activity for the detection of hydroquinone under visible light. In both systems, the detection was possible due to the presence of reactive oxygen species at the surface of TiO2 upon light, which participate in the oxidation process of the analyte. By applying a reductive potential, the oxidized form of the analyte gets reduced and a measurable amperometric response proportional to the initial analyte concentration is recorded. The third proposed setup is a ZnO-based photosensor for the quantification of 4-nitrophenol under UVA light. Nanostructured ZnO was electrochemically synthesized on FTO glass without the use of catalysts or seed layer. A post-growth annealing treatment significantly improved ZnO nanorods physicochemical properties. Subsequent modification of ZnO nanorods with a photosensitizer (perylene acid) increased the photocurrent response and the sensitivity. In this system, the detection mechanism is based on the decrease of the photocurrent response at the presence of an electron harvesting molecule, such as 4-nitrophenol. The decrease in photocurrent is proportional to the increase of 4-nitrophenol concentration in the solution. The applicability of the photoelectrochemical semiconductor-based sensing setups was verified to analyze phenolic compounds in natural and supply water samples. The proposed robust and sensitive approaches were designed for the on-site monitoring of phenolic compounds. The encouraging results confirm the potential of these photosensors as promising tools for tracelevel sensing purposes.  
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  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
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  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:186763 Serial 8850  
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Author Filez, M.; Feng, J.-Y.; Minjauw, M.M.; Solano, E.; Poonkottil, N.; Van Daele, M.; Ramachandran, R.K.; Li, C.; Bals, S.; Poelman, H.; Detavernier, C.; Dendooven, J.; Filez, M.; Minjauw, M.; Solano, E.; Poonkottil, N.; Li, C.; Bals, S.; Dendooven, J. pdf  url
doi  openurl
  Title Shuffling atomic layer deposition gas sequences to modulate bimetallic thin films and nanoparticle properties Type A1 Journal article
  Year 2022 Publication Chemistry of materials Abbreviated Journal  
  Volume (down) Issue Pages  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Atomic layer deposition (ALD) typically employs metal precursors and co-reactant pulses to deposit thin films in a layer-by-layer fashion. While conventional ABAB-type ALD sequences implement only two functionalities, namely, a metal source and ligand exchange agent, additional functionalities have emerged, including etching and reduction agents. Herein, we construct gas-phase sequences-coined as ALD+-with complex-ities reaching beyond the classic ABAB-type ALD by freely combining multiple functionalities within irregular pulse schemes, e.g., ABCADC. The possibilities of such combinations are explored as a smart strategy to tailor bimetallic thin films and nanoparticle (NP) properties. By doing so, we demonstrate that bimetallic thin films can be tailored with target thickness and through the full compositional range, while the morphology can be flexibly modulated from thin films to NPs by shuI 1ing the pulse sequence. These complex pulse schemes are expected to be broadly applicable but are here explored for Pd-Ru bimetallic thin films and NPs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000823205700001 Publication Date 2022-06-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756; 1520-5002 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited 2 Open Access OpenAccess  
  Notes This research was funded by the Research Foundation, Flanders (FWO) , and the Special Research Fund BOF of Ghent University (GOA 01G01019) . M.F. and M.M.M. acknowledge the FWO for a postdoctoral research fellowship (1280621N) . N.P. acknowledges the European Union's Horizon 2020 research and innovation program under the Marie Skiodowska-Curie grant agreement no. 765378. For the GISAXS measurements, the author s received funding from the European Community's Transnational Access Program CALIPSOplus. E.S. acknowledges the Spanish project RTI2018-093996-B-C32 MICINN/FEDER funds. Air Liquide is acknowledged for supporting this research. The authors acknowledge SOLEIL for the provision of synchrotron radiation facilities and would like to thank Dr. Alessandro Coati for assistance in using beamline SiXS. The GIWAXS experiments were performed at NCD-SWEET beamline at ALBA Synchrotron with the collaboration of ALBA staff . Approved no  
  Call Number UA @ admin @ c:irua:189541 Serial 8928  
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Author Thiruvottriyur Shanmugam, S. openurl 
  Title Singlet oxygen-based photoelectrochemical detection of nucleic acids Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages 217 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)  
  Abstract MicroRNAs (miRNAs) are small oligonucleotides (18-25 bases) that play a key role in epigenetic regulation. Since the discovery of miRNAs in 1993, their role in biological processes has been extensively investigated. By now, it has been evidenced that monitoring and detection of miRNAs can improve (early) disease diagnosis. The existing diagnostic approaches have limitations such as the need for complex multistep protocols for sample preparation, analysis, data interpretation, high cost of equipment, the need for highly qualified personnel, and high laboratory standards. As opposed to this, point-of-care biosensors and chips aim to facilitate the procedure and avoid sending samples into centralized laboratories, which saves time, reduces the chance of sample degradation, and enables analysis of patient samples in remote areas, directly at home or primary and secondary care facilities (i.e. general practitioners and specialists). The latter is essential for therapy assessment and follow-up monitoring of patients with chronic diseases and cancer. Nevertheless, the development of such sensors is lagging compared to the projections of 10 – 20 years ago, mainly due to insufficient sensitivity, poor reproducibility, and the complexity of the sensors’ design reported in the research literature. This motivates the development of new detection strategies and technologies such as photoelectrochemical sensors that combine the best features of different sensing approaches. The primary concern when developing detection technologies for miRNA is the need for a highly sensitive and selective platform. This thesis explores a novel photoelectrochemical (PEC) method that is distinctive owing to its sensitive nature and simple and robust design. Firstly, we focused on the usage of recently emerging commercial gold-sputtered electrode systems for the detection of short nucleic acid with enzymatic amplification. Importantly, cleaning such electrodes is a challenge since the standard procedures known for regular disk electrodes such as polishing cannot be employed here, since it will damage the protective layer on the electrode. However, the electrodes can be washed and pretreated chemically and/or electrochemically. Thus, a procedure to effectively clean and modify the gold-sputtered electrode has been developed, resulting in high-performance gold-sputtered nucleic acid sensors. Next, the usage of molecular photosensitizers as an alternative to enzymatic amplification has been evaluated. We took advantage of the singlet oxygen production by photosensitizers upon photoexcitation, leading to a photocurrent response due to the singlet oxygen-induced (electro)chemical conversions. Following the demonstration of the detection strategy, the analytical performance of the sensing system was evaluated using magnetic beads-based nucleic acid assay on disposable electrode platforms, with a focus to enhance the sensitivity and robustness of the technique in detecting complementary nucleic acid targets. Following the fundamental evaluation of the singlet oxygen-based PEC detection of nucleic acids, we further optimized the assay and measurement parameters and employed the sensing strategy for a polymerase chain reaction-free (PCR-free) quantification of miRNAs related to prostate cancer. By successfully detecting and quantifying low-picomolar range concentrations (< 10 pM) in plasma samples from prostate cancer patients, we successfully showed the applicability of the novel sensing strategy. We have also compared and positioned the performance of our developed PEC strategy with an existing state-of-art technique, i.e. electrochemiluminescence (ECL). Our PEC strategy performed on par with ECL, both yielding low-picomolar detection limits in serum matrices, however quicker and cheaper than ECL. Owing to the versatility of this PEC technique, the final study explored its multiplexing capability. As a starting point in this branch of the research, we have investigated two possible ways for multiplexing. To perform multiple measurements at the same time, constructing calibration plots and quantifying unknown miRNA concentrations in patient samples at the same time, we have developed a high-throughput detection with 96X multi-channel electrode systems and in-house designed and constructed 96XLED illumination sources. Secondly, to detect more than one target miRNA in a single measurement, intra-vial multiplexing where the samples were analyzed for different targets in one vial was also explored. Altogether, this thesis presents the fundamentals, development and application of a novel PEC strategy for detecting short (< 25 bases) nucleic acid sequences, in particular, miRNA. With an aim to serve as a distinctive technique to function as a clinical testing platform without any need for PCR, this work adds value to the development of nucleic acid-based sensors for miRNAs and other short-stranded nucleic acid biomarkers, and benefits in the early detection of diseases like cancer.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:191753 Serial 8931  
Permanent link to this record
 

 
Author Neven, L. file  openurl
  Title Singlet oxygen-based photoelectrochemical detection of phenolic contaminants Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume (down) Issue Pages 234 p.  
  Keywords Doctoral thesis; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)  
  Abstract Phenolic compounds can be found everywhere in our daily lives but exhibit high toxicity, low (bio)degradability and hormone-disrupting effects when they are released in the environment. It is for this reason imperative to develop detection strategies for these pollutants. A promising approach involves the use of a photoelectrochemical (PEC) sensor. In this sensor, a photosensitiser (PS) type II, which generates 1O2 under illumination, is used to oxidise phenolic compounds present in the sample. The oxidised phenols are reduced at the electrode surface leading to the generation of an electrocatalytic redox cycle. In this thesis, an in-depth understanding, through the identification of the reactive oxygen species (ROS) in the PEC sensing mechanism, is obtained. The detection strategy is optimised by choosing the PS with the highest 1O2 production and by optimising the detection parameters so that the PEC sensor can be successfully applied for the detection of phenols in industrial samples. First, it was determined that the use of highly fluorinated zinc phthalocyanine derivatives, F52PcZn and F64PcZn, as photocatalysts was optimal for the sensing of phenol due to their high 1O2 production and improved single-site isolation. However, next to 1O2, it was shown that the ROS O2•- and H2O2 were also generated in the PEC sensor. Their contribution to the photocurrent response was studied by rotating disk electrode measurements in function of the pH and applied potential. After this, the PEC detection strategy was optimised in terms of pH and applied potential for the detection of doxycycline, cefadroxil, and phenol. It was found that the use of alkaline pH-levels led to nmol L-1-level detection limits. The combination with square wave voltammetry (SWV) was, also, proposed to allow the quantification and identification of phenolic compounds in a specific sample. At last, the developed PEC and SWV sensors were applied for the measurement of phenolic compounds in industrial water samples. The PEC sensor could follow the decrease of the phenolic concentration throughout the wastewater treatment process while the SWV sensor provided the electrochemical fingerprints of these samples. The thesis concluded that the use of the PEC sensor was advantageous in the measurement of lower concentrated phenolic samples due to its high sensitivity and fast measurement time in comparison to commercial test kits.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:187029 Serial 8932  
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