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Author Monico, L.; Chieli, A.; De Meyer, S.; Cotte, M.; de Nolf, W.; Falkenberg, G.; Janssens, K.; Romani, A.; Miliani, C.
Title Role of the relative humidity and the Cd/Zn stoichiometry in the photooxidation process of cadmium yellows (CdS/Cd1-xZnxS) in oil paintings Type A1 Journal article
Year 2018 Publication Chemistry: a European journal Abbreviated Journal Chem-Eur J
Volume (down) 24 Issue 45 Pages 11584-11593
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Cadmium yellows (CdYs) refer to a family of cadmium sulfide pigments, which have been widely used by artists since the late 19th century. Despite being considered stable, they are suffering from discoloration in iconic paintings, such as Joy of Life by Matisse, Flowers in a blue vase by Van Gogh, and The Scream by Munch, most likely due to the formation of CdSO4 center dot nH(2)O. The driving factors of the CdYs degradation and how these affect the overall process are still unknown. Here, we study a series of oil mock-up paints made of CdYs of different stoichiometry (CdS/Cd0.76Zn0.24S) and crystalline structure (hexagonal/ cubic) before and after aging at variable relative humidity under exposure to light and in darkness. Synchrotron radiation-based X-ray methods combined with UV-Vis and FTIR spectroscopy show that: 1) Cd0.76Zn0.24S is more susceptible to photooxidation than CdS; both compounds can act as photocatalysts for the oil oxidation. 2) The photooxidation of CdS/Cd0.76Zn0.24S to CdSO4 center dot nH(2)O is triggered by moisture. 3) The nature of alteration products depends on the aging conditions and the Cd/Zn stoichiometry. Based on our findings, we propose a scheme for the mechanism of the photocorrosion process and the photocatalytic activity of CdY pigments in the oil binder. Overall, our results form a reliable basis for understanding the degradation of CdS-based paints in artworks and contribute towards developing better ways of preserving them for future generations.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000441126900012 Publication Date 2018-06-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-6539 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.317 Times cited 5 Open Access
Notes ; The research was financially supported by the European research project IPERION-CH, funded by the European Commission, H2020-INFRAIA-2014-2015 (Grant agreement n. 654028) and by the BOF-GOA Project SOLARPaint (University of Antwerp Research Council). For the beamtime grants received, we thank the ESRF (experiments n. HG64, HG95 and in-house beamtimes) and PETRA III-DESY (experiments: I-20130221 EC, I-20160126 EC). We are also grateful to Dr. Jan Garrevoet for his contribution to set up the P06-beamline at PETRA III-DESY. ; Approved Most recent IF: 5.317
Call Number UA @ admin @ c:irua:153733 Serial 5821
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Author Xiao, S.; Lu, Y.; Xiao, B.-Y.; Wu, L.; Song, J.-P.; Xiao, Y.-X.; Wu, S.-M.; Hu, J.; Wang, Y.; Chang, G.-G.; Tian, G.; Lenaerts, S.; Janiak, C.; Yang, X.-Y.; Su, B.-L.
Title Hierarchically dual-mesoporous TiO2 microspheres for enhanced photocatalytic properties and lithium storage Type A1 Journal article
Year 2018 Publication Chemistry: a European journal Abbreviated Journal Chem-Eur J
Volume (down) 24 Issue 50 Pages 13246-13252
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Hierarchically dual‐mesoporous TiO2 microspheres have been synthesized via a solvothermal process in the presence of 1‐butyl‐3‐methylmidazolium tetrafluoroborate ([BMIm][BF4]) and diethylenetriamine (DETA) as co‐templates. Secondary mesostructured defects in the hierarchical TiO2 microspheres produce the oxygen vacancies, which not only significantly enhance the photocatalytic activity on degrading methyl blue (over 1.7 times to P25) and acetone (over 2.9 times of P25), but which also are beneficial for lithium storage. Moreover, we propose a mechanism to obtain a better understanding of the role of dual mesoporosity of TiO2 microspheres for enhancing the molecular diffusion, ion transportation and electron transformation.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000443804100025 Publication Date 2018-06-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-6539 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.317 Times cited 6 Open Access
Notes ; This work is supported by the National Key R&D Program of China (2017YFC1103800), the Program for Changjiang Scholars and Innovative Research Team in University (IRT 15R52), the National Natural Science Foundation of China (U1662134, U1663225, 51472190, 51611530672, 51503166, 21706199, 21711530705), the International Science & Technology Cooperation Program of China (2015DFE52870), the Natural Science Foundation of Hubei Province (2016CFA033, 2017CFB487), the Open Project Program of State Key Laboratory of Petroleum Pollution Control (PPC2016007), and the CNPC Research Institute of Safety and Environmental Technology. ; Approved Most recent IF: 5.317
Call Number UA @ admin @ c:irua:151812 Serial 5957
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Author Verbruggen, S.W.
Title TiO2 photocatalysis for the degradation of pollutants in gas phase : from morphological design to plasmonic enhancement Type A1 Journal article
Year 2015 Publication Journal of photochemistry and photobiology: C: photochemistry reviews Abbreviated Journal J Photoch Photobio C
Volume (down) 24 Issue Pages 64-82
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract TiO2-based photocatalysis has become a viable technology in various application fields such as (waste)water purification, photovoltaics/artificial photosynthesis, environmentally friendly organic synthesis and remediation of air pollution. Because of the increasing impact of bad air quality worldwide, this review focuses on the use and optimization of TiO2-based photocatalysts for gas phase applications. Over the past years various specific aspects of TiO2 photocatalysis have been reviewed individually. The intent of this review is to offer a broad tutorial on (recent) trends in TiO2 photocatalyst modification for the intensification of photocatalytic air treatment. After briefly introducing the fundamentals of photocatalysis, TiO2 photocatalyst modification is discussed both on a morphological and an electronic level from the perspective of gas phase applications. The main focus is laid on recent developments, but also possible opportunities to the field. This review is intended as a solid introduction for researchers new to the field, as well as a summarizing update for established investigators. (C) 2015 Elsevier B.V. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000360420600004 Publication Date 2015-07-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1389-5567 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.317 Times cited 121 Open Access
Notes ; The author wishes to thank the Research Foundation Flanders (FWO) for the financial support and postdoctoral fellowship. ; Approved Most recent IF: 12.317; 2015 IF: 16.091
Call Number UA @ admin @ c:irua:127801 Serial 5997
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Author Compernolle, T.; Van Passel, S.; Lebbe, L.; Vangronsveld, J.; Thewys, T.
Title Populieren en hun bacteriën : een sanering hoeft niet altijd duur en ingrijpend te zijn Type A3 Journal article
Year 2010 Publication Nieuwsbrief milieu & economie Abbreviated Journal
Volume (down) 24 Issue 5 Pages 15-17
Keywords A3 Journal article; Economics
Abstract
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Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:140852 Serial 6237
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Author Fatemi, M.; Azadi, H.; Rafiaani, P.; Taheri, F.; Dubois, T.; Van Passel, S.; Witlox, F.
Title Effects of supply chain management on tomato export in Iran : application of structural equation modeling Type A1 Journal article
Year 2018 Publication Journal of food products marketing Abbreviated Journal
Volume (down) 24 Issue 2 Pages 177-195
Keywords A1 Journal article; Economics; Engineering Management (ENM); Government and Law
Abstract Although Iran is one of the top 10 countries in the world that produce tomatoes, the level that they are exported into the global market is low. This issue may have resulted from a major problem within tomatoes supply chain management. This paper aims to develop an empirical model of the supply chain management (SCM) of tomato companies. Throughout the reviewed literature, a SCM construct with different six indicators has been developed, including information sharing, long-term relationship, cooperation, quality, flexibility, and delivery. In this study, the influence of the SCM components on tomato export was identified through the use of empirical data that were collected from 20 different tomato companies in Northeast Iran. Using structural equation modeling, the major elements of SCM were found to have significant impacts on the export of tomatoes. The results also showed that information sharing, cooperation, flexibility, quality, and delivery had significant positive effects on the export of tomatoes.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000424803000004 Publication Date 2017-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1045-4446 ISBN Additional Links UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:149044 Serial 6192
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Author Zhao, H.; Li, C.-F.; Yong, X.; Kumar, P.; Palma, B.; Hu, Z.-Y.; Van Tendeloo, G.; Siahrostami, S.; Larter, S.; Zheng, D.; Wang, S.; Chen, Z.; Kibria, M.G.; Hu, J.
Title Coproduction of hydrogen and lactic acid from glucose photocatalysis on band-engineered Zn1-xCdxS homojunction Type A1 Journal article
Year 2021 Publication iScience Abbreviated Journal
Volume (down) 24 Issue 2 Pages 102109
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Photocatalytic transformation of biomass into value-added chemicals coupled with co-production of hydrogen provides an explicit route to trap sunlight into the chemical bonds. Here, we demonstrate a rational design of Zn1-xCdxS solidsolution homojunction photocatalyst with a pseudo-periodic cubic zinc blende (ZB) and hexagonal wurtzite (WZ) structure for efficient glucose conversion to simultaneously produce hydrogen and lactic acid. The optimized Zn0.6Cd0.4S catalyst consists of a twinning superlattice, has a tuned bandgap, and displays excellent efficiency with respect to hydrogen generation (690 +/- 27.6 mu mol.h(-1).g(cat).(-1)), glucose conversion (similar to 90%), and lactic acid selectivity (similar to 87%) without any co-catalyst under visible light irradiation. The periodic WZ/ZB phase in twinning superlattice facilitates better charge separation, while superoxide radical (center dot O-2(-)) and photogenerated holes drive the glucose transformation and water oxidation reactions, respectively. This work demonstrates that rational photocatalyst design could realize an efficient and concomitant production of hydrogen and value-added chemicals from glucose photocatalysis.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000621266700080 Publication Date 2021-01-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2589-0042 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:176744 Serial 6720
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Author Vervloessem, E.; Gorbanev, Y.; Nikiforov, A.; De Geyter, N.; Bogaerts, A.
Title Sustainable NOxproduction from air in pulsed plasma: elucidating the chemistry behind the low energy consumption Type A1 Journal article
Year 2022 Publication Green Chemistry Abbreviated Journal Green Chem
Volume (down) 24 Issue 2 Pages 916-929
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract N-Based fertilisers are paramount to support our still-growing world population. Current industrial N<sub>2</sub>fixation is heavily fossil fuel-dependent, therefore, a lot of work is put into the development of fossil-free pathways. Plasma technology offers a fossil-free and flexible method for N<sub>2</sub>fixation that is compatible with renewable energy sources. We present here a pulsed plasma jet for direct NO<sub><italic>x</italic></sub>production from air. The pulsed power allows for a record-low energy consumption (EC) of 0.42 MJ (mol N)<sup>−1</sup>. This is the lowest reported EC in plasma-based N<sub>2</sub>fixation at atmospheric pressure thus far. We compare our experimental data with plasma chemistry modelling, and obtain very good agreement. Hence, we can use our model to explain the underlying mechanisms responsible for this low EC. The pulsed power and the corresponding pulsed gas temperature are the reason for the very low EC: they provide a strong vibrational–translational non-equilibrium and promote the non-thermal Zeldovich mechanism. This insight is important for the development of the next generation of plasma sources for energy-efficient NO<sub><italic>x</italic></sub>production.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000739578400001 Publication Date 2021-12-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9262 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.8 Times cited Open Access Not_Open_Access
Notes H2020 European Research Council, grant agreement no. 810182 – SCOPE ERC Synergy project ; Herculesstichting; Fonds Wetenschappelijk Onderzoek, EOS ID 30505023 FWO grant ID GoF9618n ; Universiteit Antwerpen; This research was supported by the Excellence of Science FWO-FNRS project (NITROPLASM, FWO grant ID GoF9618n, EOS ID 30505023), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 810182 – SCOPE ERC Synergy project), and through long-term structural funding (Methusalem). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (Department EWI) and the UAntwerpen. We thank E. H. Choi and coworkers from the Plasma Bioscience Research Center (Korea) for providing the Soft Jet plasma source, as well as K. van’t Veer and C. Verheyen for the fruitful discussion on the electron loss fraction calculations. The graphical abstract was designed using resources from Flaticon.com. Approved Most recent IF: 9.8
Call Number PLASMANT @ plasmant @c:irua:185450 Serial 6906
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Author Sebhatu, K.T.; Gezahegn, T.W.; Berhanu, T.; Maertens, M.; Van Passel, S.; D'Haese, M.
Title Exploring variability across cooperatives : economic performance of agricultural cooperatives in northern Ethiopia Type A1 Journal article
Year 2021 Publication The international food and agribusiness management review Abbreviated Journal
Volume (down) 24 Issue 3 Pages 397-419
Keywords A1 Journal article; Engineering Management (ENM)
Abstract The number of agricultural cooperatives increased quickly in Ethiopia since the 1990s. While many papers studied the impact of membership of Ethiopian cooperatives, not much is known on their performance. This study takes a cooperative-level perspective which is unique in an African context. It compares the economic performance proxied by sales revenue and profit of a wide range of agricultural cooperatives in northern Ethiopia. Data were collected from 511 agricultural cooperatives in 12 districts of Tigray. The contributing factors of the performance are analyzed with Ordinary Least Squares regression (OLS) and Heckman selection models. Our results underscore the importance of membership size, total assets, presence of conflict among members, and union membership. Chairperson characteristics and the internal organization of a cooperative seem to be less correlated to performance.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000645416400002 Publication Date 2021-03-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1096-7508; 1559-2448 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:179025 Serial 6923
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Author Windels, S.; Diefenhardt, T.; Jain, N.; Marquez, C.; Bals, S.; Schlummer, M.; De Vos, D.E.
Title Catalytic upcycling of PVC waste-derived phthalate esters into safe, hydrogenated plasticizers Type A1 Journal article
Year 2022 Publication Green chemistry : cutting-edge research for a greener sustainable future Abbreviated Journal Green Chem
Volume (down) 24 Issue 2 Pages 754-766
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Recycling of end-of-life polyvinyl chloride (PVC) calls for solutions to deal with the vast amounts of harmful phthalate plasticizers that have historically been incorporated in PVC. Here, we report on the upcycling of such waste-extracted phthalate esters into analogues of the much safer diisononyl 1,2-cyclohexanedicarboxylate plasticizer (DINCH), via a catalytic one-pot (trans)esterification-hydrogenation process. For most of the virgin phthalates, Ru/Al2O3 is a highly effective hydrogenation catalyst, yielding >99% ring-hydrogenated products under mild reaction conditions (0.1 mol% Ru, 80 degrees C, 50 bar H-2). However, applying this reaction to PVC-extracted phthalates proved problematic, (1) as benzyl phthalates are hydrogenolyzed to benzoic acids that inhibit the Ru-catalyst, and (2) because impurities in the plasticizer extract (PVC, sulfur) further retard the hydrogenation. These complications were solved by coupling the hydrogenation to an in situ (trans)esterification with a higher alcohol, and by pretreating the extract with an activated carbon adsorbent. In this way, a real phthalate extract obtained from post-consumer PVC waste was eventually completely (>99%) hydrogenated to phthalate-free, cycloaliphatic plasticizers.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000726865200001 Publication Date 2021-11-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9262; 1463-9270 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.8 Times cited 8 Open Access Not_Open_Access
Notes This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement no. 821366 (programma acronym: Circular Flooring). D. E. D. V. thanks FWO for project funding (SBO project S001819N Triple Cycle); N. J. and S. B. acknowledge the financial support from FWO and FNRS (EOS 30489208). Finally, the authors also thank S. Smolders for assistance with the TGA-MS experiments and D. Paredaens for his experimental contribution Approved Most recent IF: 9.8
Call Number UA @ admin @ c:irua:184746 Serial 6958
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Author Pattyn, C.; Maira, N.; Buddhadasa, M.; Vervloessem, E.; Iseni, S.; Roy, N.C.; Remy, A.; Delplancke, M.-P.; De Geyter, N.; Reniers, F.
Title Disproportionation of nitrogen induced by DC plasma-driven electrolysis in a nitrogen atmosphere Type A1 Journal article
Year 2022 Publication Green Chemistry Abbreviated Journal Green Chem
Volume (down) 24 Issue 18 Pages 7100-7112
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Nitrogen disproportionation i.e. its simultaneous conversion to compounds of higher (NOx) and lower (NH3) oxidation states in a N-2 DC plasma-driven electrolysis process with a plasma cathode is investigated. This type of plasma-liquid interaction exhibits a growing interest for many applications, in particular nitrogen fixation where it represents a green alternative to the Haber-Bosch process. Optical emission spectroscopy, FTIR and electrochemical sensing systems are used to characterize the gas phase physico-chemistry while the liquid phase is analyzed via ionic chromatography and colorimetric assays. Experiments suggest that lowering the discharge current enhances nitrogen reduction and facilitates the transfer of nitrogen compounds to the liquid phase. Large amounts of water vapor appear to impact the gas discharge physico-chemistry and to favor the vibrational excitation of N-2, a key parameter for an energy-efficient nitrogen fixation.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000847733600001 Publication Date 2022-08-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9262; 1463-9270 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 9.8
Call Number UA @ admin @ c:irua:190655 Serial 7145
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Author Demirkol, Ö.; Sevik, C.; Demiroğlu, I.
Title First principles assessment of the phase stability and transition mechanisms of designated crystal structures of pristine and Janus transition metal dichalcogenides Type A1 Journal article
Year 2022 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume (down) 24 Issue 12 Pages 7430-7441
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Two-dimensional Transition Metal Dichalcogenides (TMDs) possessing extraordinary physical properties at reduced dimensionality have attracted interest due to their promise in electronic and optical device applications. However, TMD monolayers can show a broad range of different properties depending on their crystal phase; for example, H phases are usually semiconductors, while the T phases are metallic. Thus, controlling phase transitions has become critical for device applications. In this study, the energetically low-lying crystal structures of pristine and Janus TMDs are investigated by using ab initio Nudged Elastic Band and molecular dynamics simulations to provide a general explanation for their phase stability and transition properties. Across all materials investigated, the T phase is found to be the least stable and the H phase is the most stable except for WTe2, while the T' and T '' phases change places according to the TMD material. The transition energy barriers are found to be large enough to hint that even the higher energy phases are unlikely to undergo a phase transition to a more stable phase if they can be achieved except for the least stable T phase, which has zero barrier towards the T ' phase. Indeed, in molecular dynamics simulations the thermodynamically least stable T phase transformed into the T ' phase spontaneously while in general no other phase transition was observed up to 2100 K for the other three phases. Thus, the examined T ', T '' and H phases were shown to be mostly stable and do not readily transform into another phase. Furthermore, so-called mixed phase calculations considered in our study explain the experimentally observed lateral hybrid structures and point out that the coexistence of different phases is strongly stable against phase transitions. Indeed, stable complex structures such as metal-semiconductor-metal architectures, which have immense potential to be used in future device applications, are also possible based on our investigation.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000766791000001 Publication Date 2022-02-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.3 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.3
Call Number UA @ admin @ c:irua:187184 Serial 7164
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Author Bellizotti Souza, J.C.; Vizarim, N.P.; Reichhardt, C.J.O.; Reichhardt, C.; Venegas, P.A.
Title Clogging, diode and collective effects of skyrmions in funnel geometries Type A1 Journal article
Year 2022 Publication New journal of physics Abbreviated Journal New J Phys
Volume (down) 24 Issue 10 Pages 103030-14
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using a particle-based model, we examine the collective dynamics of skyrmions interacting with a funnel potential under dc driving as the skyrmion density and relative strength of the Magnus and damping terms are varied. For driving in the easy direction, we find that increasing the skyrmion density reduces the average skyrmion velocity due to jamming of skyrmions near the funnel opening, while the Magnus force causes skyrmions to accumulate on one side of the funnel array. For driving in the hard direction, there is a critical skyrmion density below which the skyrmions become trapped. Above this critical value, a clogging effect appears with multiple depinning and repinning states where the skyrmions can rearrange into different clogged configurations, while at higher drives, the velocity-force curves become continuous. When skyrmions pile up near the funnel opening, the effective size of the opening is reduced and the passage of other skyrmions is blocked by the repulsive skyrmion-skyrmion interactions. We observe a strong diode effect in which the critical depinning force is higher and the velocity response is smaller for hard direction driving. As the ratio of Magnus force to dissipative term is varied, the skyrmion velocity varies in a non-linear and non-monotonic way due to the pile up of skyrmions on one side of the funnels. At high Magnus forces, the clogging effect for hard direction driving is diminished.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000873333400001 Publication Date 2022-10-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.3 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.3
Call Number UA @ admin @ c:irua:192178 Serial 7287
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Author Yorulmaz, U.; Šabani, D.; Yagmurcukardes, M.; Sevik, C.; Milošević, M.V.
Title High-throughput analysis of tetragonal transition metal Xenes Type A1 Journal article
Year 2022 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume (down) 24 Issue 48 Pages 29406-29412
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We report a high-throughput first-principles characterization of the structural, mechanical, electronic, and vibrational properties of tetragonal single-layer transition metal Xenes (t-TMXs). Our calculations revealed 22 dynamically, mechanically and chemically stable structures among the 96 possible free-standing layers present in the t-TMX family. As a fingerprint for their structural identification, we identified four characteristic Raman active phonon modes, namely three in-plane and one out-of-plane optical branches, with various intensities and frequencies depending on the material in question. Spin-polarized electronic calculations demonstrated that anti-ferromagnetic (AFM) metals, ferromagnetic (FM) metals, AFM semiconductors, and non-magnetic semiconductor materials exist within this family, evidencing the potential of t-TMXs for further use in multifunctional heterostructures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000892446100001 Publication Date 2022-11-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.3 Times cited 1 Open Access Not_Open_Access
Notes Approved Most recent IF: 3.3
Call Number UA @ admin @ c:irua:192762 Serial 7310
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Author Tavkhelidze, I.; Cassisa, C.; Gielis, J.; Ricci, P.E.
Title About “bulky” links, generated by generalized Möbius Listing's bodies GML3n Type A1 Journal article
Year 2013 Publication Matematica e applicazioni : atti della Accademia nazionale dei Lincei Abbreviated Journal
Volume (down) 24 Issue 1 Pages 11-38
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In the present paper we consider the “bulky knots'' and ”bulky links'', which appear after cutting a Generalized Möbius Listing's GMLn3 body (whose radial cross section is a plane 3-symmetric figure with three vertices) along different Generalized Möbius Listing's surfaces GMLn2 situated in it. This article is aimed to investigate the number and geometric structure of the independent objects appearing after such a cutting process of GMLn3 bodies. In most cases we are able to count the indices of the resulting mathematical objects according to the known tabulation for Knots and Links of small complexity.
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Publisher Place of Publication Editor
Language Wos 000316567700002 Publication Date 2013-03-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1120-6357 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:107174 Serial 7405
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Author Rojas, C.M.; Artaxo, P.; Van Grieken, R.
Title Aerosols in Santiago de Chile : a study using receptor modeling with X-ray fluorescence and single particle analysis Type A1 Journal article
Year 1990 Publication Atmospheric environment: part B : urban atmosphere Abbreviated Journal
Volume (down) 24 Issue 2 Pages 227-241
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Between 15 January and 26 February 1987, 51 fine and coarse mode aerosol samples were collected at the Universidad de Santiago de Chile Planetarium using a dichotomous sampler. The samples were analyzed by X-ray fluorescence for up to 17 elements (Mg, Al, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb). Aerosol particles were individually studied by Electron Probe Microanalysis (EPMA) and Laser Microprobe Mass Analysis (LAMMA). The data set consisting of aerosol elemental concentrations and meteorological variables was subjected to Principal Factor Analysis (PFA), allowing the identification of six fine mode particle source classes (soil, industrial, sulfate particles, traffic, residual oil, wood-burnings), and five coarse mode particle source classes (soil, industrial, traffic, residual oil, sulfate particles). Both PFA solutions explained about 81 and 90% of the total variance in the data set, respectively. The regression of elemental mass concentrations on the Absolute Principal Factor Scores allowed the estimation of the contribution of the different source classes to the Santiago aerosol. Within the fine fraction, secondary SO42− particles were responsible for about 49% of the fine mode aerosol mass concentration, while 26, 13, 6.4 and 5.6% were attributed to wood-burning/car exhausts, residual oil combustion, soil dust/metallurgical, and soil dust/wood-burning releases, respectively. The coarse fraction source apportionment was mainly dominated by soil dust, accounting for 74% of the coarse mode aerosol mass concentration. A composite of soil dust and industrial release accounted for 13%; a composite of secondary sulfates contributed with 9%; a composite of soil dust and automotive emissions, and secondary sulfates were responsible for 4 and 0.03% of the coarse aerosol mass concentration, respectively. EPMA results are in satisfactory agreement with those from the bulk analysis and allowed the identification of eight particle types in both fine and coarse mode aerosols, pertaining to different source classes, namely soil, seaspray, secondary SO42−, metallurgical emissions and biomass burning release. EPMA also evidenced that one of the most abundant particle types corresponded to marine aerosol, having an average diameter of 0.7 μm for the fine mode and 2.2 μm for the coarse mode aerosol. LAMMA results indicate that, in fact, seaspray has been transported into the city of Santiago de Chile airshed, suffering several transformations and a sulfur enrichment. This analytical technique also provided evidence of the abundance of carbon-rich particles, which were not detected by either the bulk X-ray analysis or EPMA; they are probably due to fossil-fuel combustion releases.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2003-08-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-1272; 1878-2132 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:116456 Serial 7427
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Author Verbueken, A.H.; van de Vijver, F.L.; de Broe, M.E.; Van Grieken, R.E.
Title Applications of laser microprobe mass analysis in medicine Type A3 Journal article
Year 1987 Publication CRC critical reviews in clinical laboratory sciences Abbreviated Journal
Volume (down) 24 Issue Pages 263-285
Keywords A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0590-8191 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:116775 Serial 7485
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Author Düking, R.; Gielis, J.; Liese, W.
Title Carbon flux and carbon stock in a bamboo stand and their relevance for mitigating climate change Type A3 Journal article
Year 2011 Publication Bamboo Science & Culture Abbreviated Journal
Volume (down) 24 Issue 1 Pages 1-6
Keywords A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In this report we describe the basics of biological carbon fixation in bamboo forests. Confusing carbon stock with carbon flux has led to false expectations on the significance of bamboo forests as carbon sinks. Furthermore, misunderstandings about the growth of bamboo culms can lead to highly exaggerated expectations on the productivity of bamboo.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1535-7635 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:91091 Serial 7578
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Author Graham, B.; Guyon, P.; Maenhaut, W.; Taylor, P.E.; Ebert, M.; Matthias-Maser, S.; Mayol-Bracero, O.L.; Godoi, R.H.M.; Artaxo, P.; Meixner, F.X.; Lima Moura, M.A.; d'Almeida Rocha, C.H.E.; Van Grieken, R.; Glovsky, M.M.; Flagan, R.C.; Andreae, M.O.
Title Composition and diurnal variability of the natural Amazonian aerosol Type A1 Journal article
Year 2003 Publication Journal of geophysical research Abbreviated Journal
Volume (down) 24 Issue 4765 Pages 5,1-16
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000187858400009 Publication Date 2003-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0148-0227; 2156-2202; 0022-1406; 0196-6928; 0196-6936; 0885-3401; 8755-8556; 0196-2256; 0747-7309; 1 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:43523 Serial 7700
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Author Eisma, D.; Kalf, J.; Karmini, M.; Mook, W.G.; Van Put, A.; Bernard, P.; Van Grieken, R.
Title Dispersal of suspended matter in Makasar Strait and the Flores Basin Type A1 Journal article
Year 1989 Publication Netherlands journal of sea research Abbreviated Journal
Volume (down) 24 Issue 4 Pages 383-398
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In November 1984 in Makasar and the Flores Basin water samples were collected (T, S, dissolved O2, total CO2), bottom samples (sediment composition) and suspended matter (particle composition, particle size). A sediment trap was moored in the Flores Basin at 4600 m depth for nearly four months, covering the dry season. In the Flores Basin there are indications for bottom flow resuspending bottom material or preventing suspended material from settling; in Makasar Strait there is probably inflow of deep water both from the south and from the north, resulting in a very slow bottom water flor. Bottom deposits in Makasar Strait and the Flores Basin are predominantly terrigenous, with an admixture of organic carbonate and silica (mostly coccoliths). Volcanic material is primarily present near to the volcanoes in the south and reaches the deeper basins by slumping. In the suspended matter no volcanic particles and little planktonic material were found, although the latter form 10 to 15% of the top sediment and of the material deposited in the sediment trap. In suspension particles with a large concentration of tin (Sn) were found associated mainly with iron. They probably come from northern Kalimantan or northern Sulawesi. Suspended matter concentrations were mainly less than 0.5 mg·dm−3, only off the Mahakam river mouth were concentrations higher than 1 mg·dm−3. Particle size was erratic because of the variable composition of the coarser particles in suspension. Organic matter concentrations in suspension (in mg·dm−3) roughly follow the distribution of total suspended matter but organic content (in %) of the suspended matter does not show any trends. All organic matter in suspension is of marine origin except in the Mahakam river and estuary. Deposition rates, as estimated from the sediment trap results, are 150 mg·cm−2·a−1 for the total sediment, 26 mg·cm−2·a−1 for carbonate and 13 mg·cm−2·a−1 for organic matter. Flocs and fibres in suspension were only found in and below the Mahakam river plume that reaches ca 400 km from the river mouth to the southeast, and in surface waters associated with plankton (diatoms). The formation of these flocs (broken-up macroflocs or marine snow) is primarily related to particle concentration, turbulence, and the presence of organisms that produce sticky material or glue particles together.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2003-08-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0077-7579; 1873-1406 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:116825 Serial 7814
Permanent link to this record
 

 
Author Demirtas, M.; Odaci, C.; Perkgoz, N.K.; Sevik, C.; Ay, F.
Title Low Loss Atomic Layer Deposited Al2O3 Waveguides for Applications in On-Chip Optical Amplifiers Type A1 Journal article
Year 2018 Publication IEEE journal of selected topics in quantum electronics Abbreviated Journal
Volume (down) 24 Issue 4 Pages 3100508
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present the growth and optimization of ultralow loss Si-based Al2O3 planar waveguides, which have a high potential to boost the performance of rare-earth ion doped waveguide devices operating at visible and C-band wavelength ranges. The planar waveguide structures are grown using thermal atomic layer deposition. Systematic characterization of the obtained thin films is performed by spectroscopic ellipsometry, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analyses, and the optimum parameters are identified. The optical loss measurements for both transverse electric (TE) and transverse magnetic polarized light at 633, 829, and 1549 nm are performed. The lowest propagation loss value of 0.04 +/- 0.02 dB/cm for the Al2O3 waveguides for TE polarization at 1549 nm is demonstrated.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000431396300001 Publication Date 2018-04-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1077-260x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:193780 Serial 8187
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Author Cristale, J.; Álvarez-Martín, A.; Rodriguez-Cruz, S.; Sanchez-Martin, M.J.; Lacorte, S.
Title Sorption and desorption of organophosphate esters with different hydrophobicity by soils Type A1 Journal article
Year 2017 Publication Environmental Science and Pollution Research Abbreviated Journal
Volume (down) 24 Issue 36 Pages 27870-27878
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Organophosphate esters (OPEs) are ubiquitous contaminants with potentially hazardous effects on both the environment and human health. Knowledge about the soil sorption-desorption process of organic chemicals is important in order to understand their fate, mobility, and bioavailability, enabling an estimation to be made of possible risks to the environment and biota. The aim of this study was to use the batch equilibrium technique to evaluate the sorption-desorption behavior of seven OPEs (TCEP, TCPP, TBEP, TDCP, TBP, TPhP, and EHDP) in soils with distinctive characteristics (two unamended soils and a soil amended with sewage sludge). The equilibrium concentrations of the OPEs were determined by high performance liquid chromatography coupled to a triple quadrupole mass spectrometer (HPLC-MS/MS). All the compounds were sorbed by the soils, and soil organic carbon (OC) played an important role in this process. The sorption of the most soluble OPEs (TCEP, TCPP, and TBEP) depended on soil OC content, although desorption was 58.1%. The less water-soluble OPEs (TDCP, TBP, TPhP, and EHDP) recorded total sorption (100% for TPhP and EHDP) or very high sorption (34.9%) by all the soils and were not desorbed, which could be explained by their highly hydrophobic nature, as indicated by the logarithmic octanol/water partition coefficient (K-ow) values higher than 3.8, resulting in a high affinity for soil OC. The results of the sorption-desorption of the OPEs by soils with different characteristics highlighted the influence of these compounds' physicochemical properties and the content and nature of soil OC in this process.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000417874400025 Publication Date 2017-10-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0944-1344; 1614-7499 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:160642 Serial 8558
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Author Koirala, B.; Rasti, B.; Bnoulkacem, Z.; de Lima Ribeiro, A.; Madriz, Y.; Herrmann, E.; Gestels, A.; De Kerf, T.; Lorenz, S.; Fuchs, M.; Janssens, K.; Steenackers, G.; Gloaguen, R.; Scheunders, P.
Title A multisensor hyperspectral benchmark dataset for unmixing of intimate mixtures Type A1 Journal article
Year 2024 Publication IEEE sensors journal Abbreviated Journal
Volume (down) 24 Issue 4 Pages 4694-4710
Keywords A1 Journal article; Engineering sciences. Technology; Vision lab; Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract Optical hyperspectral cameras capture the spectral reflectance of materials. Since many materials behave as heterogeneous intimate mixtures with which each photon interacts differently, the relationship between spectral reflectance and material composition is very complex. Quantitative validation of spectral unmixing algorithms requires high-quality ground truth fractional abundance data, which are very difficult to obtain. In this work, we generated a comprehensive laboratory ground truth dataset of intimately mixed mineral powders. For this, five clay powders (Kaolin, Roof clay, Red clay, mixed clay, and Calcium hydroxide) were mixed homogeneously to prepare 325 samples of 60 binary, 150 ternary, 100 quaternary, and 15 quinary mixtures. Thirteen different hyperspectral sensors have been used to acquire the reflectance spectra of these mixtures in the visible, near, short, mid, and long-wavelength infrared regions (350-15385) nm. Overlaps in wavelength regions due to the operational ranges of each sensor and variations in acquisition conditions resulted in a large amount of spectral variability. Ground truth composition is given by construction, but to verify that the generated samples are sufficiently homogeneous, XRD and XRF elemental analysis is performed. We believe these data will be beneficial for validating advanced methods for nonlinear unmixing and material composition estimation, including studying spectral variability and training supervised unmixing approaches. The datasets can be downloaded from the following link: https://github.com/VisionlabHyperspectral/Multisensor_datasets.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001173599400063 Publication Date 2023-12-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-437x; 1558-1748 ISBN Additional Links UA library record; WoS full record
Impact Factor 4.3 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.3; 2024 IF: 2.512
Call Number UA @ admin @ c:irua:203094 Serial 9059
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Author Faraji, F.; Neyts, E.C.; Milošević, M.V.; Peeters, F.M.
Title Capillary Condensation of Water in Graphene Nanocapillaries Type A1 Journal Article
Year 2024 Publication Nano Letters Abbreviated Journal Nano Lett.
Volume (down) 24 Issue 18 Pages 5625-5630
Keywords A1 Journal Article; CMT
Abstract Recent experiments have revealed that the macroscopic Kelvin equation remains surprisingly accurate even for nanoscale capillaries. This phenomenon was so far explained by the oscillatory behavior of the solid−liquid interfacial free energy. We here demonstrate thermodynamic and capillarity inconsistencies with this explanation. After revising the Kelvin equation, we ascribe its validity at nanoscale confinement to the effect of disjoining pressure.

To substantiate our hypothesis, we employed molecular dynamics simulations to evaluate interfacial heat transfer and wetting properties. Our assessments unveil a breakdown in a previously established proportionality between the work of adhesion and the Kapitza conductance at capillary heights below 1.3 nm, where the dominance of the work of adhesion shifts primarily from energy to entropy. Alternatively, the peak density of the initial water layer can effectively probe the work of adhesion. Unlike under bulk conditions, high confinement renders the work of adhesion entropically unfavorable.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2024-05-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links
Impact Factor 10.8 Times cited Open Access
Notes This work was supported by Research Foundation-Flanders (FWO, project No. G099219N). The computational resources used in this work were provided by the HPC core facility CalcUA of the University of Antwerp, and the Flemish Supercomputer Center (VSC), funded by FWO and the Flemish Government. Approved Most recent IF: 10.8; 2024 IF: 12.712
Call Number UA @ lucian @ Serial 9123
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Author Li, C.; Lyu, Y.-Y.; Yue, W.-C.; Huang, P.; Li, H.; Li, T.; Wang, C.-G.; Yuan, Z.; Dong, Y.; Ma, X.; Tu, X.; Tao, T.; Dong, S.; He, L.; Jia, X.; Sun, G.; Kang, L.; Wang, H.; Peeters, F.M.; Milošević, M.V.; Wu, P.; Wang, Y.-L.
Title Unconventional superconducting diode effects via antisymmetry and antisymmetry breaking Type A1 Journal article
Year 2024 Publication Nano letters Abbreviated Journal
Volume (down) 24 Issue 14 Pages 4108-4116
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Symmetry breaking plays a pivotal role in unlocking intriguing properties and functionalities in material systems. For example, the breaking of spatial and temporal symmetries leads to a fascinating phenomenon: the superconducting diode effect. However, generating and precisely controlling the superconducting diode effect pose significant challenges. Here, we take a novel route with the deliberate manipulation of magnetic charge potentials to realize unconventional superconducting flux-quantum diode effects. We achieve this through suitably tailored nanoengineered arrays of nanobar magnets on top of a superconducting thin film. We demonstrate the vital roles of inversion antisymmetry and its breaking in evoking unconventional superconducting effects, namely a magnetically symmetric diode effect and an odd-parity magnetotransport effect. These effects are nonvolatilely controllable through in situ magnetization switching of the nanobar magnets. Our findings promote the use of antisymmetry (breaking) for initiating unconventional superconducting properties, paving the way for exciting prospects and innovative functionalities in superconducting electronics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001193010700001 Publication Date 2024-03-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record
Impact Factor 10.8 Times cited Open Access
Notes Approved Most recent IF: 10.8; 2024 IF: 12.712
Call Number UA @ admin @ c:irua:205553 Serial 9180
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Author Lu, Y.-G.; Verbeeck, J.; Turner, S.; Hardy, A.; Janssens, S.D.; De Dobbelaere, C.; Wagner, P.; Van Bael, M.K.; Van Tendeloo, G.
Title Analytical TEM study of CVD diamond growth on TiO2 sol-gel layers Type A1 Journal article
Year 2012 Publication Diamond and related materials Abbreviated Journal Diam Relat Mater
Volume (down) 23 Issue Pages 93-99
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The early growth stages of chemical vapor deposition (CVD) diamond on a solgel TiO2 film with buried ultra dispersed diamond seeds (UDD) have been studied. In order to investigate the diamond growth mechanism and understand the role of the TiO2 layer in the growth process, high resolution transmission electron microscopy (HRTEM), energy-filtered TEM and electron energy loss spectroscopy (EELS) techniques were applied to cross sectional diamond film samples. We find evidence for the formation of TiC crystallites inside the TiO2 layer at different diamond growth stages. However, there is no evidence that diamond nucleation starts from these crystallites. Carbon diffusion into the TiO2 layer and the chemical bonding state of carbon (sp2/sp3) were both extensively investigated. We provide evidence that carbon diffuses through the TiO2 layer and that the diamond seeds partially convert to amorphous carbon during growth. This carbon diffusion and diamond to amorphous carbon conversion make the seed areas below the TiO2 layer grow and bend the TiO2 layer upwards to form the nucleation center of the diamond film. In some of the protuberances a core of diamond seed remains, covered by amorphous carbon. It is however unlikely that the remaining seeds are still active during the growth process.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000302887600017 Publication Date 2012-01-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-9635; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.561 Times cited 16 Open Access
Notes Iap; Esteem 026019; Fwo Approved Most recent IF: 2.561; 2012 IF: 1.709
Call Number UA @ lucian @ c:irua:95037UA @ admin @ c:irua:95037 Serial 111
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Author Abakumov, A.M.; Batuk, D.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Tsirlin, A.A.; Niermann, D.; Waschowski, F.; Hemberger, J.; Van Tendeloo, G.; Antipov, E.V.
Title Antiferroelectric (Pb,Bi)1-xFe1+xO3-y perovskites modulated by crystallographic shear planes Type A1 Journal article
Year 2011 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume (down) 23 Issue 2 Pages 255-265
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We demonstrate for the first time a possibility to vary the anion content in perovskites over a wide range through a long-range-ordered arrangement of crystallographic shear (CS) planes. Anion-deficient perovskites (Pb,Bi)1−xFe1+xO3−y with incommensurately modulated structures were prepared as single phases in the compositional range from Pb0.857Bi0.094Fe1.049O2.572 to Pb0.409Bi0.567Fe1.025O2.796. Using a combination of electron diffraction and high-resolution scanning transmission electron microscopy, we constructed a superspace model describing a periodic arrangement of the CS planes. The model was verified by refinement of the Pb0.64Bi0.32Fe1.04O2.675 crystal structure from neutron powder diffraction data ((3 + 1)D S.G. X2/m(α0γ), X = [1/2,1/2,1/2,1/2], a = 3.9082(1) Å, b = 3.90333(8) Å, c = 4.0900(1) Å, β = 91.936(2)°, q = 0.05013(4)a* + 0.09170(3)c* at T = 700 K, RP = 0.036, RwP = 0.048). The (Pb,Bi)1−xFe1+xO3−y structures consist of perovskite blocks separated by CS planes confined to nearly the (509)p perovskite plane. Along the CS planes, the perovskite blocks are shifted with respect to each other over the 1/2[110]p vector that transforms the corner-sharing connectivity of the FeO6 octahedra in the perovskite framework to an edge-sharing connectivity of the FeO5 pyramids at the CS plane, thus reducing the oxygen content. Variation of the chemical composition in the (Pb,Bi)1−xFe1+xO3−y series occurs mainly because of a changing thickness of the perovskite block between the interfaces, that can be expressed through the components of the q vector as Pb6γ+2αBi1−7γ−αFe1+γ−αO3−3γ−α. The Pb, Bi, and Fe atoms are subjected to strong displacements occurring in antiparallel directions on both sides of the perovskite blocks, resulting in an antiferroelectric-type structure. This is corroborated by the temperature-, frequency-, and field-dependent complex permittivity measurements. Pb0.64Bi0.32Fe1.04O2.675 demonstrates a remarkably high resistivity >0.1 T Ω cm at room temperature and orders antiferromagnetically below TN = 608(10) K.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000286160800018 Publication Date 2010-12-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 29 Open Access
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number UA @ lucian @ c:irua:88651 Serial 136
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Author Belik, A.A.; Abakumov, A.M.; Tsirlin, A.A.; Hadermann, J.; Kim, J.; Van Tendeloo, G.; Takayama-Muromachi, E.
Title Article Structure and magnetic properties of BiFe0.75Mn0.25O3 perovskite prepared at ambient and high pressure Type A1 Journal article
Year 2011 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume (down) 23 Issue 20 Pages 4505-4514
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Solid solutions of BiFe1xMnxO3 (0.0 ≤ x ≤ 0.4) were prepared at ambient pressure and at 6 GPa. The ambient-pressure (AP) phases crystallize in space group R3c similarly to BiFeO3. The high-pressure (HP) phases crystallize in space group R3c for x = 0.05 and in space group Pnma for 0.15 ≤ x ≤ 0.4. The structure of HP-BiFe0.75Mn0.25O3 was investigated using synchrotron X-ray powder diffraction, electron diffraction, and transmission electron microscopy. HP-BiFe0.75Mn0.25O3 has a PbZrO3-related √2ap × 4ap × 2√2ap (ap is the parameter of the cubic perovskite subcell) superstructure with a = 5.60125(9) Å, b = 15.6610(2) Å, and c = 11.2515(2) Å similar to that of Bi0.82La0.18FeO3. A remarkable feature of this structure is the unconventional octahedral tilt system, with the primary ab0a tilt superimposed on pairwise clockwise and counterclockwise rotations around the b-axis according to the oioi sequence (o stands for out-of-phase tilt, and i stands for in-phase tilt). The (FeMn)O6 octahedra are distorted, with one longer metaloxygen bond (2.222.23 Å) that can be attributed to a compensation for covalent BiO bonding. Such bonding results in the localization of the lone electron pair on Bi3+ cations, as confirmed by electron localization function analysis. The relationship between HP-BiFe0.75Mn0.25O3 and antiferroelectric structures of PbZrO3 and NaNbO3 is discussed. On heating in air, HP-BiFe0.75Mn0.25O3 irreversibly transforms to AP-BiFe0.75Mn0.25O3 starting from about 600 K. Both AP and HP phases undergo an antiferromagnetic ordering at TN ≈ 485 and 520 K, respectively, and develop a weak net magnetic moment at low temperatures. Additionally, ceramic samples of AP-BiFe0.75Mn0.25O3 show a peculiar phenomenon of magnetization reversal.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000295897400015 Publication Date 2011-09-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 57 Open Access
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number UA @ lucian @ c:irua:93581 Serial 151
Permanent link to this record
 

 
Author Neek-Amal, M.; Peeters, F.M.
Title Buckled circular monolayer graphene : a graphene nano-bowl Type A1 Journal article
Year 2011 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume (down) 23 Issue 4 Pages 045002-045002,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the stability of circular monolayer graphene subjected to a radial load using non-equilibrium molecular dynamics simulations. When monolayer graphene is radially stressed, after some small circular strain (~0.4%) it buckles and bends into a new bowl-like shape. Young's modulus is calculated from the linear relation between stress and strain before the buckling threshold, which is in agreement with experimental results. The prediction of elasticity theory for the buckling threshold of a radially stressed plate is presented and its results are compared to the one of our atomistic simulation. The Jarzynski equality is used to estimate the difference between the free energy of the non-compressed states and the buckled states. From a calculation of the free energy we obtain the optimum radius for which the system feels the minimum boundary stress.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000286142800003 Publication Date 2010-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 27 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 2.649; 2011 IF: 2.546
Call Number UA @ lucian @ c:irua:88043 Serial 259
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Author Yang, Z.; Schryvers, D.
Title Composition gradients surrounding Ni4Ti3 precipitates in a NiTi alloy studied by EELS, EFTEM and EDX Type A1 Journal article
Year 2006 Publication International journal of applied electromagnetics and mechanics Abbreviated Journal Int J Appl Electrom
Volume (down) 23 Issue 1/2 Pages 17-24
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1383-5416 ISBN Additional Links UA library record; WoS full record;
Impact Factor 0.769 Times cited Open Access
Notes Approved Most recent IF: 0.769; 2006 IF: 0.262
Call Number UA @ lucian @ c:irua:59610 Serial 443
Permanent link to this record
 

 
Author Bogaerts, A.
Title Computer simulations of argon-hydrogen Grimm-type glow discharges Type A1 Journal article
Year 2008 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom
Volume (down) 23 Issue Pages 1476-1486
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Computer simulations have been performed to describe the effect of small admixtures of hydrogen to an argon glow discharge in the Grimm-type configuration. The two-dimensional density profiles of the various plasma species (i.e., electrons, Ar+, ArH+, H+, H2+ and H3+ ions, H atoms and H2 molecules, Ar metastable atoms and sputtered Cu atoms) are presented for 1% H2 added to the argon glow discharge, and the effect of different H2 additions (varying between 0.1 and 10%) on the species densities, the hydrogen dissociation degree, and the sputtering process, are investigated. Finally, the relative contributions of various production and loss processes for the different plasma species are calculated.
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Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000260309700002 Publication Date 2008-10-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0267-9477;1364-5544; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.379 Times cited 23 Open Access
Notes Approved Most recent IF: 3.379; 2008 IF: 4.028
Call Number UA @ lucian @ c:irua:70950 Serial 468
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