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Author |
Gielis, J.; Brasili, S. |
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Title |
Proceedings of the 1st International Symposium on Square Bamboos and the Geometree (ISSBG 2022) |
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ME3 Book as editor |
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Year |
2023 |
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Pages |
xi, 175 p. |
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Keywords |
ME3 Book as editor; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Publication Date |
2023-11-29 |
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978-90-833839-0-3 |
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UA library record |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:201049 |
Serial |
9077 |
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Author |
Deylgat, E.; Chen, E.; Sorée, B.; Vandenberghe, W.G. |
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Title |
Quantum transport study of contact resistance of edge- and top-contacted two-dimensional materials |
Type |
P1 Proceeding |
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Year |
2023 |
Publication |
International Conference on Simulation of Semiconductor Processes and Devices : [proceedings]
T2 – International Conference on Simulation of Semiconductor Processes and, Devices (SISPAD), SEP 27-29, 2023, Kobe, Japan |
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45-48 |
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Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
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Abstract |
We calculate the contact resistance for an edge- and top-contacted 2D semiconductor. The contact region consists of a metal contacting a monolayer of MoS2 which is otherwise surrounded by SiO2. We use the quantum transmitting boundary method to compute the contact resistance as a function of the 2D semiconductor doping concentration. An effective mass Hamiltonian is used to describe the properties of the various materials. The electrostatic potentials are obtained by solving the Poisson equation numerically. We incorporate the effects of the image-force barrier lowering on the Schottky barrier and examine the impact on the contact resistance. At low doping concentrations, the contact resistance of the top contact is lower compared to edge contact, while at high doping concentrations, the edge contact exhibits lower resistance. |
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001117703800012 |
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2023-11-20 |
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978-4-86348-803-8 |
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UA library record; WoS full record |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:202839 |
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9079 |
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Author |
Derks, K.; Youchaeva, M.; Van der Snickt, G.; Van der Stighelen, K.; Janssens, K. |
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Title |
Reconstructing Sweerts : practical insights into the historical dark halo technique based on paint reconstructions |
Type |
P1 Proceeding |
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Year |
2024 |
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Pages |
259-271
T2 - Alla maniera : technical art history |
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Keywords |
P1 Proceeding; Engineering sciences. Technology; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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978-90-429-5216-4 |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:203062 |
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9082 |
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Author |
Poppe, R. |
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Title |
Refining short-range order parameters from diffuse electron scattering |
Type |
Doctoral thesis |
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Year |
2023 |
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Abbreviated Journal |
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Pages |
iv, 150 p. |
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Doctoral thesis; Electron microscopy for materials research (EMAT) |
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Electrons, X-rays and neutrons that pass through a thin crystalline sample will be diffracted. Diffraction patterns of crystalline materials contain Bragg reflections (sharp discrete intensity maxima) and diffuse scattering (a weak continuous background). The Bragg reflections contain information about the average crystal structure (the type of atoms and the average atomic positions), whereas the diffuse scattering contains information about the short-range order (deviations from the average crystal structure that are ordered on a local scale). Because the properties of many materials depend on the short-range order, refining short-range order parameters is essential for understanding and optimizing material properties. The refinement of short-range order parameters has previously been applied to the diffuse scattering in single-crystal X-ray and single-crystal neutron diffraction data but not yet to the diffuse scattering in single-crystal electron diffraction data. In this work, we will verify the possibility to refine short-range order parameters from the diffuse scattering in single-crystal electron diffraction data. Electron diffraction allows to acquire data on submicron-sized crystals, which are too small to be investigated with single-crystal X-ray and single-crystal neutron diffraction. In the first part of this work, we will refine short-range order parameters from the one-dimensional diffuse scattering in electron diffraction data acquired on the lithium-ion battery cathode material Li1.2Ni0.13Mn0.54Co0.13O2. The number of stacking faults and the twin percentages will be refined from the diffuse scattering using a Monte Carlo refinement. We will also describe a method to determine the spinel/layered phase ratio from the intensities of the Bragg reflections in electron diffraction data. In the second part of this work, we will refine short-range order parameters from the three-dimensional diffuse scattering in both single-crystal electron and single-crystal X-ray diffraction data acquired on Nb0.84CoSb. The correlations between neighbouring vacancies and the displacements of Sb and Co atoms will be refined from the diffuse scattering using a Monte Carlo refinement and a three-dimensional difference pair distribution function refinement. The effect of different experimental parameters on the spatial resolution of the observed diffuse scattering will also be investigated. Finally, the model of the short-range Nb-vacancy order in Nb0.84CoSb will also be applied to LiNi0.5Sn0.3Co0.2O2. |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:200610 |
Serial |
9084 |
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Author |
Ysebaert, T.; Samson, R.; Denys, S. |
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Title |
Revisiting dry deposition modelling of particulate matter on vegetation at the microscale |
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A1 Journal article |
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Year |
2023 |
Publication |
Air quality, atmosphere & health |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Dry deposition is an important process determining pollutant concentrations, especially when studying the influence of urban green infrastructure on particulate matter (PM) levels in cities. Computational fluid dynamics (CFD) models of PM capture by vegetation are useful tools to increase their applicability. The meso-scale models of Zhang et al. (Atmos Environ 35:549-560, 2001) and Petroff and Zhang (Geosci Model Dev 3(2):753-769, 2010) have often been adopted in CFD models, however a comparison of these models with measurements including all PM particle sizes detrimental to health has been rarely reported and certainly not for green wall species. This study presents dry deposition experiments on real grown Hedera helix in a wind tunnel setup with wind speeds from 1 to 4 m s(-1) and PM consisting of a mixture of soot (0.02 – 0.2 mu mu m) and dust particles (0.3 – 10 mu mu m). Significant factors determining the collection efficiency (%) were particle diameter and wind speed, but relative air humidity and the type of PM (soot or dust) did not have a significant influence. Zhang's model outperformed Petroff's model for particles < 0.3 mu mu m, however the inclusion of turbulent impaction in Petroff's model resulted in better agreement with the measurements for particles > 2 – 3 mu mu m. The optimised model had an overall root-mean-square-error of similar to 4% for collection efficiency (CE) and 0.4 cm s-1 for deposition velocity (nu d), which was shown to be highly competitive against previously described models. It can thus be used to model PM deposition on other plant species, provided the correct parameterisation of the drag by this species. A detailed description of the spatial distribution of the vegetation could solve the underestimation for particle sizes of 0.3 – 2 mu mu m. |
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Wos |
001125841300001 |
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2023-12-14 |
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ISSN |
1873-9318; 1873-9326 |
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UA library record; WoS full record |
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Impact Factor |
5.1 |
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Most recent IF: 5.1; 2023 IF: 3.184 |
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Call Number |
UA @ admin @ c:irua:201986 |
Serial |
9086 |
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Author |
Vervloessem, E. |
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Title |
The role of pulsing and humidity in plasma-based nitrogen fixation : a combined experimental and modeling study |
Type |
Doctoral thesis |
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Year |
2023 |
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Pages |
358 p. |
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Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Nitrogen (N) is an indispensable building block for all living organisms as well as for pharmaceutical and chemical industry. In a nutshell, N is needed for plants to grow and beings to live and nitrogen fixation (NF) is the process that makes N available for plants as food by converting N2 into a reactive form, such as ammonia (NH3) or nitrogen oxides (NOx), upon reacting with O2 and H2. The aim of this thesis is to elucidate (wet) plasma-based nitrogen fixation with a focus on (1) the role of pulsing in achieving low energy consumption, (2) the role of H2O as a hydrogen source in nitrogen fixation and (3) elucidation of nitrogen fixation pathways in humid air and humid N2 plasma in a combined experimental and computational study. Furthermore, this thesis aims to take into account the knowledge-gaps and challenges identified in the discussion of the state of the art. Specifically, (1) we put our focus on branching out to another way of introducing water into the plasma system, i.e. H2O vapor, (2) we de-couple the problem for pathway elucidation by starting with characterization of the chosen plasma, next a simpler gas mixture and building up from there, (3) we include modelling, though not under wet conditions and (4) we focus on also analyzing species and performance outside liquid H2O. Firstly, based on the reaction analysis of a validated quasi-1D model, we can conclude that pulsing is indeed the key factor for energy-efficient NOx- formation, due to the strong temperature drop it causes. Secondly, the thesis shows that added H2O vapor, and not liquid H2O, is the main source of H for NH3 generation. Related to this, we discuss how the selectivity of plasma-based NF in humid air and humid N2 can be controlled by changing the humidity in the feed gas. Interestingly, NH3 production can be achieved in both N2 and air plasmas using H2O as a H source. Lastly, we identified a significant loss mechanism for NH3 and HNO2 that occurs in systems where these species are synthesized simultaneously, i.e. downstream from the plasma, HNO2 reacts with NH3 to form NH4NO2, which decomposes into N2 and H2O. This reduces the effective NF when not properly addressed, and should therefore be considered in future works aimed at optimizing plasma-based NF. In conclusion, this thesis adds further to the current state of the art of plasma-based NF both in the presence of H2O and in dry systems. |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:197038 |
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9088 |
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Author |
Peeters, H. |
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Title |
Solar active photocatalytic self-cleaning coatings based on plasmon-embedded titania |
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Doctoral thesis |
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Year |
2023 |
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Pages |
XX, 125 p. |
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Doctoral thesis; Engineering sciences. Technology |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:201390 |
Serial |
9093 |
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Author |
Dingenen, F. |
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Title |
Solar-driven H2 production from seawater using stabilized plasmon-enhanced photocatalysts |
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Doctoral thesis |
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2023 |
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XXXVIII, 210 p. |
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Doctoral thesis; Engineering sciences. Technology |
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As natural gas prices proved to be very volatile, sustainable alternatives are highly needed. Water-derived H2 was revealed as a promising substitute, allowing to produce a green energy carrier with a minimum of harmful emissions. Direct splitting of earth-abundant seawater provides an eco-friendly route for the production of clean H2, but is hampered by selectivity and stability issues due to the presence of salts.Photocatalytic seawater splitting is particularly promising for this purpose, as it seems less affected by adversary seawater effects and might rely on free and renewable solar power. Unfortunately, the benchmark photocatalyst, TiO2, still suffers from its low solar light activity. It is only actived upon illumination with energetic ultraviolet light (<5% of the sunlight). In order to broaden the activity window to the visible light, the concept of the 'plasmonic rainbow' was explored. Here, TiO2 is modified with various gold-silver composites that possess the unique optical phenomenon of Surface Plasmon Resonance (SPR). This phenomenon enables the absorption of light at very specific wavelengths, depending on the metal type, size, shape and dielectric environment. The light energy might then be converted into hot carriers, strong local electromagnetic fields and/or heat. By combining multiple composites with various sizes and compositions, a broadband absorption could be obtained, resulting in significantly enhanced activity in photocatalytic model reactions under simulated sunlight. The major disadvantage of these plasmonic nanoparticles is their tendency to oxidize and deactivate. To overcome this, polymer shell stabilization strategies were found to be effective to protect the metal cores. Both conductive and non-conductive polymers were studied. For the former, a mix-and-wait strategy generating polyaniline shells of 2-5 nm was used, whille the latter was based on a Layer-by-Layer approach, allowing (sub) nanometer thickness control. For the actual H2 production experiments, the plasmonic loading was optimized in a pure water:methanol scavenger (7:1) mixture and initially the stabilization strategies proofed to be effective for simulated seawater (0.5M NaCl), even after 2 years. However, in real seawater, the activity decreased drastically due to aggregation of the photocatalyst in the presence of multivalent cations. Finally, facile immobilization strategies using 3D printing showed to be able to yield stable, solar active photocatalyst for real seawater splitting. |
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Most recent IF: NA |
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UA @ admin @ c:irua:203196 |
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9094 |
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Menegaldo, B.; Aleccia, D.; Nuyts, G.; Amato, A.; Orsega, E.F.; Moro, G.; Balliana, E.; De Wael, K.; Moretto, L.M.; Beltran, V. |
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Title |
Stories of the life of Saint George : materials and techniques from a Barbelli mural painting |
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A1 Journal article |
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Year |
2023 |
Publication |
Studies in conservation |
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1-14 |
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A1 Journal article; Art; History; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
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Gian Giacomo Inchiocchio (1604-1656), better known as Barbelli, was one of the main exponents of Lombard painting of the seventeenth century. A large body of work is attributed to him, encompassing a wide range of drawings, murals, and oil paintings. However, despite his broad production, there are still many open questions regarding his painting techniques and materials. In this paper, a multi-analytical study of the cycle Stories of the life of Saint George that originally decorated the presbytery of the parish church of Casaletto Vaprio (Cremona, Italy) was performed, combining non-invasive techniques with the characterisation of selected micro samples. Results show that Barbelli used a very limited number of inorganic pigments, often mixing them together to create different colours and shades. Remains of caseinate and degradation products (i.e. weddellite and whewellite) related to the strappo intervention were also highlighted. The study helped to decipher the materials and technique of this painting, providing data that can be used as a reference to study his extensive production. |
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001080139100001 |
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2023-10-04 |
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ISSN |
0039-3630; 2047-0584 |
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UA library record; WoS full record |
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Impact Factor |
0.8 |
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Most recent IF: 0.8; 2023 IF: 0.578 |
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UA @ admin @ c:irua:200302 |
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9098 |
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Grünewald, L.; Chezganov, D.; De Meyer, R.; Orekhov, A.; Van Aert, S.; Bogaerts, A.; Bals, S.; Verbeeck, J. |
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Supplementary Information for “In-situ Plasma Studies using a Direct Current Microplasma in a Scanning Electron Microscope” |
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2023 |
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Dataset; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Supplementary information for the article “In-situ Plasma Studies using a Direct Current Microplasma in a Scanning Electron Microscope” containing the videos of in-situ SEM imaging (mp4 files), raw data/images, and Jupyter notebooks (ipynb files) for data treatment and plots. Link to the preprint: https://doi.org/10.48550/arXiv.2308.15123 Explanation of the data files can be found in the Information.pdf file. The Videos folder contains the in-situ SEM image series mentioned in the paper. If there are any questions/bugs, feel free to contact me at lukas.grunewaldatuantwerpen.be |
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Not_Open_Access |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:203389 |
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9100 |
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Author |
Biondo, O. |
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Towards a fundamental understanding of energy-efficient, plasma-based CO<sub>2</sub> conversion |
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Doctoral thesis |
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2023 |
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221 p. |
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Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Plasma-based CO2 conversion is worldwide gaining increasing interest. The aim of this work is to find potential pathways to improve the energy efficiency of plasma-based CO2 conversion beyond what is feasible for thermal chemistry. To do so, we use a combination of modeling and experiments to better understand the underlying mechanisms of CO2 conversion, ranging from non-thermal to thermal equilibrium conditions. Zero-dimensional (0D) chemical kinetics modelling, describing the detailed plasma chemistry, is developed to explore the vibrational kinetics of CO2, as the latter is known to play a crucial role in the energy efficient CO2 conversion. The 0D model is successfully validated against pulsed CO2 glow discharge experiments, enabling the reconstruction of the complex dynamics underlying gas heating in a pure CO2 discharge, paving the way towards the study of gas heating in more complex gas mixtures, such as CO2 plasmas with high dissociation degrees. Energy-efficient, plasma-based CO2 conversion can also be obtained upon the addition of a reactive carbon bed in the post-discharge region. The reaction between solid carbon and O2 to form CO allows to both reduce the separation costs and increase the selectivity towards CO, thus, increasing the energy efficiency of the overall conversion process. In this regard, a novel 0D model to infer the mechanism underlying the performance of the carbon bed over time is developed. The model outcome indicates that gas temperature and oxygen complexes formed at the surface of solid carbon play a fundamental and interdependent role. These findings open the way towards further optimization of the coupling between plasma and carbon bed. Experimentally, it has been demonstrated that “warm” plasmas (e.g. microwave or gliding arc plasmas) can yield very high energy efficiency for CO2 conversion, but typically only at reduced pressure. For industrial application, it will be important to realize such good energy efficiency at atmospheric pressure as well. However, recent experiments illustrate that the microwave plasma at atmospheric pressure is too close to thermal conditions to achieve a high energy efficiency. Hence, we use a comprehensive set of advanced diagnostics to characterize the plasma and the reactor performance, focusing on CO2 and CO2/CH4 microwave discharges. The results lead to a deeper understanding of the mechanism of power concentration with increasing pressure, typical of plasmas in most gases, which is of great importance for model validation and understanding of reactor performance. |
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Wos |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:197213 |
Serial |
9108 |
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| Permanent link to this record |
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Author |
Van Echelpoel, R.; De Wael, K. |
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Title |
Voltammetric drug testing makes sense at the border |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Nature Reviews Chemistry |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-2 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
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Abstract |
The European BorderSens project leverages voltammetric sensors, developed with end-users' input, to rapidly and accurately detect illicit drugs. By embracing practicalities and validation, this technology has the potential to combat the illicit drug problem. |
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Place of Publication |
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Editor |
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Language |
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Wos |
001142000900001 |
Publication Date |
2024-01-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2397-3358 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:202646 |
Serial |
9112 |
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Author |
Gao, Y.-J.; Jin, H.; Esteban, D.A.; Weng, B.; Saha, R.A.; Yang, M.-Q.; Bals, S.; Steele, J.A.; Huang, H.; Roeffaers, M.B.J. |
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Title |
3D-cavity-confined CsPbBr₃ quantum dots for visible-light-driven photocatalytic C(sp³)-H bond activation |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Carbon Energy |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
e559 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Metal halide perovskite (MHP) quantum dots (QDs) offer immense potential for several areas of photonics research due to their easy and low-cost fabrication and excellent optoelectronic properties. However, practical applications of MHP QDs are limited by their poor stability and, in particular, their tendency to aggregate. Here, we develop a two-step double-solvent strategy to grow and confine CsPbBr3 QDs within the three-dimensional (3D) cavities of a mesoporous SBA-16 silica scaffold (CsPbBr3@SBA-16). Strong confinement and separation of the MHP QDs lead to a relatively uniform size distribution, narrow luminescence, and good ambient stability over 2 months. In addition, the CsPbBr3@SBA-16 presents a high activity and stability for visible-light-driven photocatalytic toluene C(sp(3))-H bond activation to produce benzaldehyde with similar to 730 mu mol g(-1) h(-1) yield rate and near-unity selectivity. Similarly, the structural stability of CsPbBr3@SBA-16 QDs is superior to that of both pure CsPbBr3 QDs and those confined in MCM-41 with 1D channels. |
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Wos |
001223583600001 |
Publication Date |
2024-05-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2637-9368 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
|
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:206000 |
Serial |
9133 |
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| Permanent link to this record |
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Author |
Yang, C.-Q.; Yin, Z.-W.; Li, W.; Cui, W.-J.; Zhou, X.-G.; Wang, L.-D.; Zhi, R.; Xu, Y.-Y.; Tao, Z.-W.; Sang, X.; Cheng, Y.-B.; Van Tendeloo, G.; Hu, Z.-Y.; Su, B.-L. |
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Title |
Atomically deciphering the phase segregation in mixed halide perovskite |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Advanced functional materials |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-10 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Mixed-halide perovskites show promising applications in tandem solar cells owing to their adjustable bandgap. One major obstacle to their commercialization is halide phase segregation, which results in large open-circuit voltage deficiency and J-V hysteresis. However, the ambiguous interplay between structural origin and phase segregation often results in aimless and unspecific optimization strategies for the device's performance and stability. An atomic scale is directly figured out the abundant Ruddlesden-Popper anti-phase boundaries (RP-APBs) within a CsPbIBr2 polycrystalline film and revealed that phase segregation predominantly occurs at RP-APB-enriched interfaces due to the defect-mediated lattice strain. By compensating their structural lead halide, such RP-APBs are eliminated, and the decreasing of strain can be observed, resulting in the suppression of halide phase segregation. The present work provides the deciphering to precisely regulate the perovskite atomic structure for achieving photo-stable mixed halide wide-bandgap perovskites of high-efficiency tandem solar cell commercial applications. The phase segregation in mixed halide perovskite film predominantly occurs at Ruddlesden-Popper anti-phase boundaries (RP-APBs)-enriched interfaces due to the defect-mediated lattice strain. The RP-APBs defects can be eliminated by compensating for their structural lead halide deficiency, resulting in the suppression of halide phase segregation. image |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001200673300001 |
Publication Date |
2024-04-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616-301x |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
19 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 19; 2024 IF: 12.124 |
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Call Number |
UA @ admin @ c:irua:205509 |
Serial |
9134 |
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Author |
Lelouche, S.N.K.; Lemir, I.; Biglione, C.; Craig, T.; Bals, S.; Horcajada, P. |
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Title |
AuNP/MIL-88B-NH₂ nanocomposite for the valorization of nitroarene by green catalytic hydrogenation |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Chemistry: a European journal |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-10 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The efficiency of a catalytic process is assessed based on conversion, yield, and time effectiveness. However, these parameters are insufficient for evaluating environmentally sustainable research. As the world is urged to shift towards green catalysis, additional factors such as reaction media, raw material availability, sustainability, waste minimization and catalyst biosafety, need to be considered to accurately determine the efficacy and sustainability of the process. By combining the high porosity and versatility of metal organic frameworks (MOFs) and the activity of gold nanoparticles (AuNPs), efficient, cyclable and biosafe composite catalysts can be achieved. Thus, a composite based on AuNPs and the nanometric flexible porous iron(III) aminoterephthalate MIL-88B-NH2 was successfully synthesized and fully characterized. This nanocomposite was tested as catalyst in the reduction of nitroarenes, which were identified as anthropogenic water pollutants, reaching cyclable high conversion rates at short times for different nitroarenes. Both synthesis and catalytic reactions were performed using green conditions, and even further tested in a time-optimizing one-pot synthesis and catalysis experiment. The sustainability and environmental impact of the catalytic conditions were assessed by green metrics. Thus, this study provides an easily implementable synthesis, and efficient catalysis, while minimizing the environmental and health impact of the process. |
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Place of Publication |
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Wos |
001204094600001 |
Publication Date |
2024-03-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0947-6539 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
4.3 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 4.3; 2024 IF: 5.317 |
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Call Number |
UA @ admin @ c:irua:205426 |
Serial |
9135 |
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Author |
Osorio-Tejada, J.; Escriba-Gelonch, M.; Vertongen, R.; Bogaerts, A.; Hessel, V. |
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Title |
CO₂ conversion to CO via plasma and electrolysis : a techno-economic and energy cost analysis |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Energy & environmental science |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Electrification and carbon capture technologies are essential for achieving net-zero emissions in the chemical sector. A crucial strategy involves converting captured CO2 into CO, a valuable chemical feedstock. This study evaluates the feasibility of two innovative methods: plasma activation and electrolysis, using clean electricity and captured CO2. Specifically, it compares a gliding arc plasma reactor with an embedded novel carbon bed system to a modern zero-gap type low-temperature electrolyser. The plasma method stood out with an energy cost of 19.5 GJ per tonne CO, marking a 43% reduction compared to electrolysis and conventional methods. CO production costs for plasma- and electrolysis-based plants were $671 and $962 per tonne, respectively. However, due to high uncertainty regarding electrolyser costs, the CO production costs in electrolysis-based plants may actually range from $570 to $1392 per tonne. The carbon bed system in the plasma method was a key factor in facilitating additional CO generation from O-2 and enhancing CO2 conversion, contributing to its cost-effectiveness. Challenges for electrolysis included high costs of equipment and low current densities. Addressing these limitations could significantly decrease production costs, but challenges arise from the mutual relationship between intrinsic parameters, such as CO2 conversion, CO2 input flow, or energy cost. In a future scenario with affordable feedstocks and equipment, costs could drop below $500 per tonne for both methods. While this may be more challenging for electrolysis due to complexity and expensive catalysts, plasma-based CO production appears more viable and competitive. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001218045900001 |
Publication Date |
2024-05-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1754-5692; 1754-5706 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
32.5 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 32.5; 2024 IF: 29.518 |
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Call Number |
UA @ admin @ c:irua:205986 |
Serial |
9138 |
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Author |
Ahmadi Eshtehardi, H. |
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Title |
Combined computational-experimental study on plasma and plasma catalysis for N2 fixation |
Type |
Doctoral thesis |
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Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
160 p. |
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Keywords |
Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Humanity feels the urge of shifting to a sustainable society more than at any other time in its history. Electrification of chemical industry plays a key role in this transition. The possibility of producing fertilizers from air using renewable electricity, and simultaneously, no greenhouse gas emission, resulted in an increasing interest toward plasma technology as a solution for electrification of a part of the chemical industry in the past few years. Additionally, the activation of nitrogen molecules by vibrational and electronic excitation reactions in plasma can lead to an energy-efficient process. Last but not least, the modularity (fast on/off characteristic) of plasma technology makes it capable of using intermittent renewable electricity on site for the production of fertilizers using air. All these advantages offered by plasma technology make it a potential solution for the on-site production of fertilizers in small and decentralized plants using air and renewable electricity, which leads to a considerable reduction in fertilizer production and transportation costs. However, industrialization of plasma-based NF suffers from several challenges, including challenges of plasma catalysis for the selective production of desired species, the high energy cost of plasma-based NF compared to current industrial processes, and the design and development of scaled up and energy-efficient plasma reactors for industrial purposes. In the framework of this thesis we have tried to add to the state-of-the-art (SOTA) in plasma-based NOx production and deal with its limitations using a combination of experimental and modelling work. |
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Corporate Author |
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Place of Publication |
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Wos |
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Publication Date |
2024-06-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:205246 |
Serial |
9139 |
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| Permanent link to this record |
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Author |
Yao, W.; Hui, C.; Wang, L.; Wang, J.; Gielis, J.; Shi, P. |
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Title |
Comparison of the performance of two polar equations in describing the geometries of elliptical fruits |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Botany letters |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
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Abstract |
In nature, the two-dimensional (2D) profiles of fruits from many plants often resemble ellipses. However, it remains unclear whether these profiles strictly adhere to the ellipse equation, as many natural shapes resembling ellipses are actually better described as superellipses. The superellipse equation, which includes an additional parameter n compared to the ellipse equation, can generate a broader range of shapes, with the ellipse being just a special case of the superellipse. To investigate whether the 2D profiles of fruits are better described by ellipses or superellipses, we collected a total of 751 mature and undamaged fruits from 31 naturally growing plants of Cucumis melo L. var. agrestis Naud. Our analysis revealed that most adjusted root-mean-square errors (> 92% of the 751 fruits) for fitting the superellipse equation to the fruit profiles were consistently less than 0.0165. Furthermore, there were 638 of the 751 fruits (ca. 85%) with the 95% confidence intervals of the estimated parameter n in the superellipse equation not including 2. These findings suggest that the profiles of C. melo var. agrestis fruits align more closely with the superellipse equation than with the ellipse equation. This study provides evidence for the existence of the superellipse in fruit profiles, which has significant implications for studying fruit geometries and estimating fruit volumes using the solid of revolution formula. Furthermore, this discovery may contribute to a deeper understanding of the mechanisms driving the evolution of fruit shapes. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
001219634500001 |
Publication Date |
2024-05-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2381-8107; 2381-8115 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.5 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 1.5; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:205955 |
Serial |
9140 |
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Author |
Khan, S.U.; Matshitse, R.; Borah, R.; Nemakal, M.; Moiseeva, E.O.; Dubinina, T.V.; Nyokong, T.; Verbruggen, S.W.; De Wael, K. |
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Title |
Coupling of phthalocyanines with plasmonic gold nanoparticles by click chemistry for an enhanced singlet oxygen based photoelectrochemical sensing |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
ChemElectroChem |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-11 |
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Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab); Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
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Abstract |
Coupling photosensitizers (PSs) with plasmonic nanoparticles increases the photocatalytic activity of PSs as the localized surface plasmon resonance (LSPR) of plasmonic nanoparticles leads to extreme concentration of light in their vicinity known as the near-field enhancement effect. To realize this in a colloidal phase, efficient conjugation of the PS molecules with the plasmonic nanoparticle surface is critical. In this work, we demonstrate the coupling of phthalocyanine (Pc) molecules with gold nanoparticles (AuNPs) in the colloidal phase via click chemistry. This conjugated Pc-AuNPs colloidal system is shown to enhance the photocatalytic singlet oxygen (1O2) production over non-conjugated Pcs and hence improve the photoelectrochemical detection of phenols. The plasmonic enhancement of the 1O2 generation by Pcs was clearly elucidated by complementary experimental and computational classical electromagnetic models. The dependence of plasmonic enhancement on the spectral position of the excitation laser wavelength and the absorbance of the Pc molecules with respect to the wavelength specific near-field enhancement is clearly demonstrated. A high similar to 8 times enhancement is obtained with green laser (532 nm) at the LSPR due to the maximum near-field enhancement at the resonance wavelength. Zinc phthalocyanine is covalently linked to plasmonic AuNPs via click chemistry to investigate the synergistic effect that boosts the overall activity toward the detection of HQ under visible light illumination. The 1O2 quantum yield of ZnPc improved significantly after conjugating with AuNPs, resulting in enhanced photoelectrochemical activity. image |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
001214481000001 |
Publication Date |
2024-05-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2196-0216 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 4; 2024 IF: 4.136 |
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Call Number |
UA @ admin @ c:irua:205962 |
Serial |
9142 |
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| Permanent link to this record |
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Author |
Cioni, M.; Delle Piane, M.; Polino, D.; Rapetti, D.; Crippa, M.; Arslan Irmak, E.; Pavan, G.M.; Van Aert, S.; Bals, S. |
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Title |
Data for Sampling Real‐Time Atomic Dynamics in Metal Nanoparticles by Combining Experiments, Simulations, and Machine Learning |
Type |
Dataset |
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Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
Dataset; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Even at low temperatures, metal nanoparticles (NPs) possess atomic dynamics that are key for their properties but challenging to elucidate. Recent experimental advances allow obtaining atomic‐resolution snapshots of the NPs in realistic regimes, but data acquisition limitations hinder the experimental reconstruction of the atomic dynamics present within them. Molecular simulations have the advantage that these allow directly tracking the motion of atoms over time. However, these typically start from ideal/perfect NP structures and, suffering from sampling limits, provide results that are often dependent on the initial/putative structure and remain purely indicative. Here, by combining state‐of‐the‐art experimental and computational approaches, how it is possible to tackle the limitations of both approaches and resolve the atomistic dynamics present in metal NPs in realistic conditions is demonstrated. Annular dark‐field scanning transmission electron microscopy enables the acquisition of ten high‐resolution images of an Au NP at intervals of 0.6 s. These are used to reconstruct atomistic 3D models of the real NP used to run ten independent molecular dynamics simulations. Machine learning analyses of the simulation trajectories allows resolving the real‐time atomic dynamics present within the NP. This provides a robust combined experimental/computational approach to characterize the structural dynamics of metal NPs in realistic conditions. |
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Wos |
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Series Editor |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:205843 |
Serial |
9143 |
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De Luca, F.; Abate, S.; Bogaerts, A.; Centi, G. |
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Title |
Electrified CO2 conversion : integrating experimental, computational, and process simulation methods for sustainable chemical synthesis |
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Doctoral thesis |
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Year |
2024 |
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Pages |
xv, 152 p. |
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Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Nowadays, the burning of fossil fuels, particularly petroleum, natural gas, and coal, meets the rising need for power and fuels for automobiles and industries. This has given rise to ecological and climate challenges. This thesis explores these issues from three distinct perspectives: (i) experimental, (ii) computational, and (iii) process simulation, with a focus on studying CO2 as an alternative and economically viable raw material. Firstly, the experimental study is focused on the synthesis, characterization, and testing of novel catalysts for electroreduction of CO2 and oxalic acid, an intermediate product of CO2. Electrocatalysts based on Cu supported by citrus (orange and lemon) peel biomass are prepared. These catalysts exhibit activity in the electrochemical reduction of CO2, emphasizing the effectiveness of biomasses, particularly orange peels, as environmentally friendly precursors for sustainable and efficient electrocatalysts. In addition, graphitic carbon nitrides/TiO2 nanotubes (g-C3N4/TiNT) composites are prepared for the electrocatalytic reduction of oxalic acid to glycolic acid, revealing superior electrocatalytic properties compared to pristine TiNT. Characterization by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electronic microscopy were performed for all the prepared electrocatalysts. Delving into the reduction of CO2 on Cu catalysts, a computational study about the synthesis of methanol on Cu(111) surface is performed by using the Vienna Ab initio Simulation Package. A systematic study is carried out to define the activation energies of the elementary reactions by using mGGA DF. Consequently, it is shown that the rate-controlling step is CH3O* hydrogenation and the formate pathway on Cu(111) proceeds through the HCOOH* intermediate. Finally, the process simulation, performed by using the software Aspen Plus 11 from AspenTech Inc., is based on the comparison of a catalytic (oxidation of ethylene glycol) and an electrocatalytic process (CO2 electroreduction chain) to synthesize glycolic acid. An economic analysis of the operational and investment costs reveals that the catalytic process is more cost-effective due to the current instability of electrocatalysts and proton exchange membranes, resulting in increased maintenance costs and, consequently, higher prices for the product. |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:205262 |
Serial |
9147 |
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Author |
Wu, X.; Ding, J.; Cui, W.; Lin, W.; Xue, Z.; Yang, Z.; Liu, J.; Nie, X.; Zhu, W.; Van Tendeloo, G.; Sang, X. |
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Title |
Enhanced electrical properties of Bi2-xSbxTe3 nanoflake thin films through interface engineering |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Energy & environment materials |
Abbreviated Journal |
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Pages |
e12755-8 |
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A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The structure-property relationship at interfaces is difficult to probe for thermoelectric materials with a complex interfacial microstructure. Designing thermoelectric materials with a simple, structurally-uniform interface provides a facile way to understand how these interfaces influence the transport properties. Here, we synthesized Bi2-xSbxTe3 (x = 0, 0.1, 0.2, 0.4) nanoflakes using a hydrothermal method, and prepared Bi2-xSbxTe3 thin films with predominantly (0001) interfaces by stacking the nanoflakes through spin coating. The influence of the annealing temperature and Sb content on the (0001) interface structure was systematically investigated at atomic scale using aberration-corrected scanning transmission electron microscopy. Annealing and Sb doping facilitate atom diffusion and migration between adjacent nanoflakes along the (0001) interface. As such it enhances interfacial connectivity and improves the electrical transport properties. Interfac reactions create new interfaces that increase the scattering and the Seebeck coefficient. Due to the simultaneous optimization of electrical conductivity and Seebeck coefficient, the maximum power factor of the Bi1.8Sb0.2Te3 nanoflake films reaches 1.72 mW m(-1) K-2, which is 43% higher than that of a pure Bi2Te3 thin film. |
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001204495900001 |
Publication Date |
2024-04-18 |
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UA library record; WoS full record; WoS citing articles |
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Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:205438 |
Serial |
9148 |
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Author |
Vlasov, E. |
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Title |
Exploiting secondary electrons in transmission electron microscopy for 3D characterization of nanoparticle morphologies |
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Doctoral thesis |
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Year |
2024 |
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Pages |
x, 118 p. |
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Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
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Abstract |
Electron tomography (ET) is an indispensable tool for determining the three-dimensional (3D) structure of nanomaterials in (scanning) transmission electron microscopy ((S)TEM). ET enables 3D characterization of a variety of nanomaterials across different fields, including life sciences, chemistry, solid-state physics, and materials science down to atomic resolution. However, the acquisition of a conventional tilt series for ET is a time-consuming process and thus cannot capture fast transformations of materials in realistic conditions. Moreover, only a limited number of nanoparticles (NPs) can be investigated, hampering a general understanding of the average properties of the material. Therefore, alternative characterization techniques that allow for high-resolution characterization of the surface structure without the need to acquire a full tilt series in ET are required which would enable a more time-efficient investigation with better statistical value. In the first part of this work, an alternative technique for the characterization of the morphology of NPs to improve the throughput and temporal resolution of ET is presented. The proposed technique exploits surface-sensitive secondary electron (SE) imaging in STEM employed using a modification of electron beam-induced current (EBIC) setup. The time- and dose efficiency of SEEBIC are tested in comparison with ET and superior spatial resolution is shown compared to conventional scanning electron microscopy. Finally, contrast artefacts arising in SEEBIC images are described, and their origin is discussed. The second part of my thesis focuses on real applications of the proposed technique and introduces a high-throughput methodology that combines images acquired by SEEBIC with quantitative image analysis to retrieve information about the helicity of gold nanorods. It shows that SEEBIC imaging overcomes the limitation of ET providing a general understanding of the connection between structure and chiroptical properties. |
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Publication Date |
2024-06-17 |
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Most recent IF: NA |
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UA @ admin @ c:irua:204905 |
Serial |
9149 |
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Author |
Xu, H.; Li, H.; Gauquelin, N.; Chen, X.; Wu, W.-F.; Zhao, Y.; Si, L.; Tian, D.; Li, L.; Gan, Y.; Qi, S.; Li, M.; Hu, F.; Sun, J.; Jannis, D.; Yu, P.; Chen, G.; Zhong, Z.; Radovic, M.; Verbeeck, J.; Chen, Y.; Shen, B. |
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Title |
Giant tunability of Rashba splitting at cation-exchanged polar oxide interfaces by selective orbital hybridization |
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A1 Journal article |
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Year |
2024 |
Publication |
Advanced materials |
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A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The 2D electron gas (2DEG) at oxide interfaces exhibits extraordinary properties, such as 2D superconductivity and ferromagnetism, coupled to strongly correlated electrons in narrow d-bands. In particular, 2DEGs in KTaO3 (KTO) with 5d t2g orbitals exhibit larger atomic spin-orbit coupling and crystal-facet-dependent superconductivity absent for 3d 2DEGs in SrTiO3 (STO). Herein, by tracing the interfacial chemistry, weak anti-localization magneto-transport behavior, and electronic structures of (001), (110), and (111) KTO 2DEGs, unambiguously cation exchange across KTO interfaces is discovered. Therefore, the origin of the 2DEGs at KTO-based interfaces is dramatically different from the electronic reconstruction observed at STO interfaces. More importantly, as the interface polarization grows with the higher order planes in the KTO case, the Rashba spin splitting becomes maximal for the superconducting (111) interfaces approximately twice that of the (001) interface. The larger Rashba spin splitting couples strongly to the asymmetric chiral texture of the orbital angular moment, and results mainly from the enhanced inter-orbital hopping of the t2g bands and more localized wave functions. This finding has profound implications for the search for topological superconductors, as well as the realization of efficient spin-charge interconversion for low-power spin-orbitronics based on (110) and (111) KTO interfaces. An unambiguous cation exchange is discovered across the interfaces of (001), (110), and (111) KTaO3 2D electron gases fabricated at room temperature. Remarkably, the (111) interfaces with the highest superconducting transition temperature also turn out to show the strongest electron-phonon interaction and the largest Rashba spin splitting. image |
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001219658400001 |
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2024-03-13 |
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0935-9648 |
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UA library record; WoS full record |
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Impact Factor |
29.4 |
Times cited |
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Most recent IF: 29.4; 2024 IF: 19.791 |
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Call Number |
UA @ admin @ c:irua:206037 |
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9152 |
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Author |
Tsonev, I.; Ahmadi Eshtehardi, H.; Delplancke, M.-P.; Bogaerts, A. |
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Title |
Importance of geometric effects in scaling up energy-efficient plasma-based nitrogen fixation |
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A1 Journal article |
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Year |
2024 |
Publication |
Sustainable energy & fuels |
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1-19 |
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A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Despite the recent promising potential of plasma-based nitrogen fixation, the technology faces significant challenges in efficient upscaling. To tackle this challenge, we investigate two reactors, i.e., a small one, operating in a flow rate range of 5-20 ln min-1 and current range of 200-500 mA, and a larger one, operating at higher flow rate (100-300 ln min-1) and current (400-1000 mA). Both reactors operate in a pin-to-pin configuration and are powered by direct current (DC) from the same power supply unit, to allow easy comparison and evaluate the effect of upscaling. In the small reactor, we achieve the lowest energy cost (EC) of 2.8 MJ mol-1, for a NOx concentration of 1.72%, at a flow rate of 20 ln min-1, yielding a production rate (PR) of 33 g h-1. These values are obtained in air; in oxygen-enriched air, the results are typically better, at the cost of producing oxygen-enriched air. In the large reactor, the higher flow rates reduce the NOx concentration due to lower SEI, while maintaining a similar EC. This stresses the important effect of the geometrical configuration of the arc, which is typically concentrated in the center of the reactor, resulting in limited coverage of the reacting gas flow, and this is identified as the limiting factor for upscaling. However, our experiments reveal that by changing the reactor configuration, and thus the plasma geometry and power deposition mechanisms, the amount of gas treated by the plasma can be enhanced, leading to successful upscaling. To obtain more insights in our experiments, we performed thermodynamic equilibrium calculations. First of all, they show that our measured lowest EC closely aligns with the calculated minimum thermodynamic equilibrium at atmospheric pressure. In addition, they reveal that the limited NOx production in the large reactor results from the contracted nature of the plasma. To solve this limitation, we let the large reactor operate in so-called torch configuration. Indeed, the latter enhances the NOx concentrations compared to the pin-to-pin configuration, yielding a PR of 80 g h-1 at an EC of 2.9 MJ mol-1 and NOx concentration of 0.31%. This illustrates the importance of reactor design in upscaling. With the focus on feasibility evaluation of scaling-up plasma-based nitrogen fixation by combined experiments and thermodynamic modelling, we aim to tackle the challenge of design and development of an energy-efficient and scaled-up plasma reactor. |
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001203657700001 |
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2024-04-11 |
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UA library record; WoS full record |
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Most recent IF: NA |
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UA @ admin @ c:irua:205435 |
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9155 |
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Author |
Kummamuru, N.B. |
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Title |
Methane and hydrogen storage in clathrate hydrates |
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Doctoral thesis |
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Year |
2024 |
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XXV, 260 p. |
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Doctoral thesis; Engineering sciences. Technology; Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
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In a world increasingly reliant on alternative energy sources, the quest for efficient and secure storage solutions is paramount. This doctoral thesis explores the exciting potential of a familiar material – water – to act as a vault for next-generation energy sources like hydrogen (H2) and methane (CH4). Nature offers a solution in the form of clathrate hydrates, fascinating cage-like structures formed from water molecules that can trap these gas molecules within their framework. This research investigates on improving the formation kinetics and gas storage capabilities of clathrate hydrates utilizing porous materials and the interstitial space between non-porous materials to augment the contact between gas and water thereby catalysing the growth of hydrates and unlocking their full potential as efficient and secure energy storage reservoirs. A key outcome of this research is the formulation of an empirical correlation, offering predictive insights into CH4 hydrate phase equilibrium conditions. Innovative approaches utilizing thermally conductive beads have yielded substantial enhancements in CH4 uptake. Furthermore, the identification of optimal water content within porous materials showcases a pathway to maximize CH4 storage capacity and hydrate growth kinetics. In the domain of hydrogen storage, attention is also directed towards unstirred systems, where the integration of functionalized porous materials has demonstrated a significant improvement in the rate of hydrate formation and the overall H2 storage capacity. A noteworthy achievement of this research lies in the successful storage of H2 within confined CH4 hydrates through a gas exchange process and the preliminary results show the potential for safer and more sustainable method for H2 storage at mild thermodynamic conditions, offering promising prospects for future energy systems. |
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Most recent IF: NA |
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UA @ admin @ c:irua:206258 |
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9160 |
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Wang, G.; Xie, C.; Wang, H.; Li, Q.; Xia, F.; Zeng, W.; Peng, H.; Van Tendeloo, G.; Tan, G.; Tian, J.; Wu, J. |
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Mitigated oxygen loss in lithium-rich manganese-based cathode enabled by strong Zr-O affinity |
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A1 Journal article |
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2024 |
Publication |
Advanced functional materials |
Abbreviated Journal |
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2313672 |
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A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Oxygen loss is a serious problem of lithium-rich layered oxide (LLO) cathodes, as the high capacity of LLO relies on reversible oxygen redox. Oxygen release can occur at the surface leading to the formation of spinel or rock salt structures. Also, the lattice oxygen will usually become unstable after long cycling, which remains a major roadblock in the application of LLO. Here, it is shown that Zr doping is an effective strategy to retain lattice oxygen in LLO due to the high affinity between Zr and O. A simple sol-gel method is used to dope Zr4+ into the LLOs to adjust the local electronic structure and inhibit the diffusion of oxygen anions to the surface during cycling. Compared with untreated LLOs, LLO-Zr cathodes exhibit a higher cycling stability, with 94% capacity retention after 100 cycles at 0.4 C, up to 223 mAh g-1 at 1 C, and 88% capacity retention after 300 cycles. Theoretical calculations show that due to the strong Zr-O covalent bonding, the formation energy of oxygen vacancies has effectively increased and the loss of lattice oxygen under high voltage can be suppressed. This study provides a simple method for developing high-capacity and cyclability Li-rich cathode materials for lithium-ion batteries. Oxygen release can occur at the cathode surface leading to the formation of spinel or rock salt structures. Here, it is shown that Zr doping is an effective strategy to retain lattice oxygen in lithium-rich layered oxides (LLO) due to the high affinity between Zr and O. LLO-Zr exhibit higher cycling stability, with 88% capacity retention after 300 cycles at 1 C. image |
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001159843800001 |
Publication Date |
2024-02-10 |
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1616-301x |
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UA library record; WoS full record |
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Impact Factor |
19 |
Times cited |
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Approved |
Most recent IF: 19; 2024 IF: 12.124 |
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UA @ admin @ c:irua:203812 |
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9161 |
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Long, Y.; Wang, X.; Zhang, H.; Wang, K.; Ong, W.-L.; Bogaerts, A.; Li, K.; Lu, C.; Li, X.; Yan, J.; Tu, X.; Zhang, H. |
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Plasma chemical looping : unlocking high-efficiency CO₂ conversion to clean CO at mild temperatures |
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A1 Journal article |
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2024 |
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JACS Au |
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A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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We propose a plasma chemical looping CO2 splitting (PCLCS) approach that enables highly efficient CO2 conversion into O-2-free CO at mild temperatures. PCLCS achieves an impressive 84% CO2 conversion and a 1.3 mmol g(-1) CO yield, with no O-2 detected. Crucially, this strategy significantly lowers the temperature required for conventional chemical looping processes from 650 to 1000 degrees C to only 320 degrees C, demonstrating a robust synergy between plasma and the Ce0.7Zr0.3O2 oxygen carrier (OC). Systematic experiments and density functional theory (DFT) calculations unveil the pivotal role of plasma in activating and partially decomposing CO2, yielding a mixture of CO, O-2/O, and electronically/vibrationally excited CO2*. Notably, these excited CO2* species then efficiently decompose over the oxygen vacancies of the OCs, with a substantially reduced activation barrier (0.86 eV) compared to ground-state CO2 (1.63 eV), contributing to the synergy. This work offers a promising and energy-efficient pathway for producing O-2-free CO from inert CO2 through the tailored interplay of plasma and OCs. |
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001225139200001 |
Publication Date |
2024-05-08 |
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UA library record; WoS full record |
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Most recent IF: NA |
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UA @ admin @ c:irua:205970 |
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9166 |
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Lu, Q. |
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Title |
Precipitation behavior and heat resistance properties of Al-Cu-Mg-Ag-(Si) alloy |
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Doctoral thesis |
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2024 |
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Abbreviated Journal |
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VIII, 212 p. |
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Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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With the rapid increase in the speed of new-generation aerospace vehicles, conventional heat-resistant aluminum alloys cannot meet the long-term service of the equipment. Therefore, the development of new high-strength heat-resistant aluminum alloys is of great strategic for the sustainable and high-quality development of industries. Al-Cu-Mg-Ag alloy is an age-hardenable heat-resistant aluminum alloy and has high strength and heat resistance. The addition of alloying elements such as Si and Sc to Al-Cu-Mg-Ag alloy introduces a competitive relationship among the σ-Al5Cu6Mg2, θ′-Al2Cu, and Ω phases. Therefore, a systematic investigation of precipitation behavior and heat resistance of Al-Cu-Mg-Ag-(Si) is essential for guiding the design of high-strength heat-resistant aluminum alloys. Combined characterization testing methods such as scanning electron microscopy, transmission electron microscopy, atom probe tomography, microhardness testing, and tensile testing with simulation calculation methods such as calculation of phase diagram, first-principles calculations, and Ab initio molecular dynamics, the effects of heat treatment processes and element content on the precipitation behavior, mechanical properties, and heat resistance of Al-Cu-Mg-Ag-(Si) alloys were systematically investigated. Furthermore, a multiple interface segregation structure was constructed at the θ′/Al interface, and a new Al-Cu-Mg-Ag-Si-Sc alloy with synergistically improved strength and heat resistance was developed. The main conclusions are as follows: (1) Based on the Kampmann-Wagner-Numerical theory, the relationship between the coarsening rate of the Ω phase and the aging process was analyzed, revealing for the first time that the critical size of Ω phase ( ) under thermal exposure temperature was the key factor determining the coarsening rate of Ω phase during long time thermal exposure heat treatment. After artificial ageing, when the size of Ω phase was smaller than the critical size , the dissolution of smaller Ω phase leaded to a rapid decrease in the number density of Ω phases, thereby reducing the heat resistance of the alloy. When the size of Ω phase was greater than or equal to the critical size , the coarsening rate of Ω phase was consistent, but a larger initial size would result in a larger final size after long-term thermal exposure. Therefore, the closer the size of Ω phase in the alloy is to the critical size under heat exposure temperature, the better the heat resistance of the alloy. (2) A concept of constructing a multiple interface segregation structure at the precipitate/matrix interface was proposed, and based on this concept, a multiple interface segregation structure containing the C/L-AlMgSiCu interfacial phase, newly discovered χ-AgMg interfacial phase, and Sc segregation layer was successfully constructed at the θ′/Al interface. The existence of the multiple interface segregation structure ensured that the designed Al-Cu-Mg-Ag-Si-Sc alloy maintains a yield strength of 400 MPa after thermal exposure at 200 C for 100 h, with a strength retention rate of 97%, creating a new record for the synergistic improvement of strength and heat resistance in aluminum alloys. In addition, combining transmission electron microscopy ex-situ/in-situ characterization with first-principles calculations, it is shown that the χ-AgMg interface phase will be destroyed due to the diffusion of the outer Ag layer during thermal exposure, and gradually dissolve into the matrix, but it can still delay the coarsening behavior of θ′-Al2Cu phase. (3) The criteria for determining whether Ω phase can precipitate are updated in Al-Cu-Mg-Ag-Si alloys with low Mg/Si ratio based on phase diagram thermodynamic calculations and multi-scale structural characterization. When W(Mg)/W(Si) > 1.4 and X(Ag)/X(Mgexcess) > 1, Ω phase can precipitate in Al-Cu-Mg-Ag-Si alloys, where X(Mgexcess) represents the atomic percentage of residual Mg elements after the formation of the AlMgSiCu quaternary precipitate phase C/L phase in the supersaturated solid solution, and the W(Mg) is the mass fraction of Mg in the supersaturated solid solution before artificial ageing. (4) The effects of alloy element content on precipitation behavior and heat resistance of Al-Cu-Mg-Ag-Si alloys were systematically analyzed. Critical conditions for the precipitation of σ-Al5Cu6Mg2 and Ω phase in Al-Cu-Mg-Ag-Si alloys are revealed. Based on calculation of phase diagram results, the conditions for precipitating σ-Al5Cu6Mg2 phase in the alloy are: ① W(Mg)/W(Si) > 1.8; ② W(Cu) > 2.7W(Mg) – 5W(Si). When W(Mg)/W(Si) < 1.8, the alloy is mainly precipitated with C/L/Q′-AlMgSiCu. When W(Cu) < 2.7W(Mg) – 5W(Si), the alloy will generate GPB zone. In addition, W(Ag)/W(Si) > 4 is the critical condition which the Ω phase can the main precipitates in Al-Cu-Mg-Ag-Si alloys. Furthermore, the correlation between precipitate types and heat resistance was summarized, showing that Al-Cu-Mg-Ag-(Si) alloys with Ω phase as the main strengthening phase are more suitable for the preparation of structures with short service time but high temperature, while Al-Cu-Mg-Ag-(Si) alloys with low Mg content and multiple segregation structures are more suitable for structures requiring long-term service at medium to high temperatures. This study, for the first time, combines calculation of phase diagram with multi-scale microstructure characterization, systematically unraveling the effects of element content on precipitation behavior, strength, and heat resistance of Al-Cu-Mg-Ag-(Si) alloys. In addition, a concept of constructing a multiple interface segregation structure at the precipitate/matrix interface was proposed to synergistically improve alloy strength and heat resistance. This work provides theoretical guidance for optimizing the composition and processing of Al-Cu-Mg-Ag-(Si) alloy and regulating the microstructure. Furthermore, it also offers new ideas and theoretical guidance for the development of novel high-strength heat-resistant alloys in other systems. |
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UA @ admin @ c:irua:206180 |
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9167 |
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Manaigo, F. |
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Study of a gliding arc discharge for sustainable nitrogen fixation into NOx |
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2024 |
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Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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With the growth of the world population, the agricultural sector is required to meet an increasing demand for nutrients and currently relies on industrially produced fertilizers. Among them, nitrogen-based fertilizers are the most common choice and require N2 to be converted into more reactive molecules in a process called “nitrogen fixation”. This is mainly performed through the Haber-Bosch process, which, is not ideal since it requires large-scale facilities to be economical and is associated with a high energy cost and high CO2 emissions, resulting in an environmental impact that is pushing for the study of greener alternatives. Among these, plasma-based nitrogen fixation into NOx is promising, and gliding arc plasma, specifically, proved to be suitable for nitrogen fixation. This thesis aims to study plasma-based nitrogen fixation focusing on an atmospheric pressure gliding arc plasma on three different levels. On a fundamental level, an approach dealing with laser-based excitation of separate rotational lines was successfully developed. This method can be implemented on atmospheric discharges that produce rather high NOx densities and, thus, can impose essential restrictions for the use of “classical” laser-induced fluorescence methods. The approach is then implemented, providing a discussion on the two-dimensional distributions of both the gas temperature and the NO ground state density. A clear correlation between these quantities is found and the effects of both the gas temperature and the plasma power on NO and NO2 concentrations are discussed, revealing how the NO oxidation is already significant in the plasma afterglow region and how the gas flow rate is a crucial parameter affecting the temperature gradients. >From a technological level, the conventional approach of introducing external resistors to stabilize the arc is challenged by studying both its performance and its stability replacing the external resistor with an inductor. We conclude that similar stabilization results can be obtained while significantly lowering the overall energy cost, which decreased from up to a maximum of 7.9 MJ/mol N to 3 MJ/mol N. Finally, we study whether a small-scale fertilizer production facility based on a gliding arc plasma can be a local competitive alternative. This is done by proposing a comparative model to understand how capital, operative expenditures and transport costs affect the production costs. The model highlights how, with the current best available technology, plasma-based nitrogen fixation, while being an interesting alternative for NOx synthesis, still requires a more efficient use of H2 for direct NH3 production. |
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UA @ admin @ c:irua:205259 |
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9175 |
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