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Author Komulainen, S.; Verlackt, C.; Pursiainen, J.; Lajunen, M.
Title Oxidation and degradation of native wheat starch by acidic bromate in water at room temperature Type A1 Journal article
Year 2013 Publication Carbohydrate Polymers Abbreviated Journal Carbohyd Polym
Volume 93 Issue 1 Pages 73-80
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract Native wheat starch was oxidized by benign acidic bromate in water at room temperature. HPLC-ELSD study indicated that starch degraded in the course of oxidation but it still had a polymeric structure characterized by H-1, C-13, HSQC and HMBC NMR measurements. Products were generally water-soluble fragments but the use of a short reaction time and dilute reaction mixture yielded water-insoluble products. Titration of the products showed, that the increase of the starch content and reaction time increased the content of carbonyl and carboxyl groups in the range of 0.5-2.5% and 1.7-17.2%, respectively, in the product fragments. A mechanism for the oxidation reaction was proposed. (C) 2012 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000316512900011 Publication Date 2012-06-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0144-8617; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.811 Times cited 32 Open Access
Notes Approved Most recent IF: 4.811; 2013 IF: 3.916
Call Number UA @ lucian @ c:irua:108288 Serial 2537
Permanent link to this record
 
 
Author Lu, A.K.A.; Houssa, M.; Luisier, M.; Pourtois, G.
Title Impact of layer alignment on the behavior of MoS2-ZrS2 tunnel field-effect transistors : an ab initio study Type A1 Journal article
Year 2017 Publication Physical review applied Abbreviated Journal Phys Rev Appl
Volume 8 Issue 3 Pages 034017
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Tunnel field-effect transistors based on van der Waals heterostructures are emerging device concepts for low-power applications, auguring sub-60 mV/dec subthreshold swing values. In these devices, the channel is built from a stack of several different two-dimensional materials whose nature allows tailoring the band alignments and enables a good electrostatic control of the device. In this work, we propose a theoretical study of the variability of the performances of a MoS2-ZrS2 tunnel field-effect transistor induced by fluctuations of the relative position or the orientation of the layers. Our results indicate that although a steep subthreshold slope (20 mV/dec) is achievable, fluctuations in the relative orientation of the ZrS2 layer with respect to the MoS2 one lead to a significant variability in the tunneling current by about one decade. This arises from changes in the orbital overlap between the layers and from the modulation of the transport direction.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication College Park, Md Editor
Language Wos 000411460400001 Publication Date 2017-09-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2331-7019 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.808 Times cited 6 Open Access OpenAccess
Notes Approved Most recent IF: 4.808
Call Number UA @ lucian @ c:irua:146741 Serial 4785
Permanent link to this record
 
 
Author de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P.
Title Defects in amorphous semiconductors : the case of amorphous indium gallium zinc oxide Type A1 Journal article
Year 2018 Publication Physical review applied Abbreviated Journal Phys Rev Appl
Volume 9 Issue 9 Pages 054039
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Based on a rational classification of defects in amorphous materials, we propose a simplified model to describe intrinsic defects and hydrogen impurities in amorphous indium gallium zinc oxide (a-IGZO). The proposed approach consists of organizing defects into two categories: point defects, generating structural anomalies such as metal-metal or oxygen-oxygen bonds, and defects emerging from changes in the material stoichiometry, such as vacancies and interstitial atoms. Based on first-principles simulations, it is argued that the defects originating from the second group always act as perfect donors or perfect acceptors. This classification simplifies and rationalizes the nature of defects in amorphous phases. In a-IGZO, the most important point defects are metal-metal bonds (or small metal clusters) and peroxides (O-O single bonds). Electrons are captured by metal-metal bonds and released by the formation of peroxides. The presence of hydrogen can lead to two additional types of defects: metal-hydrogen defects, acting as acceptors, and oxygen-hydrogen defects, acting as donors. The impact of these defects is linked to different instabilities observed in a-IGZO. Specifically, the diffusion of hydrogen and oxygen is connected to positive-and negative-bias stresses, while negative-bias illumination stress originates from the formation of peroxides.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication College Park, Md Editor
Language Wos 000433070900003 Publication Date 2018-05-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2331-7019 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.808 Times cited 7 Open Access OpenAccess
Notes Approved Most recent IF: 4.808
Call Number UA @ lucian @ c:irua:151497 Serial 5019
Permanent link to this record
 
 
Author Yin, L.; Juneja, R.; Lindsay, L.; Pandey, T.; Parker, D.S.
Title Semihard iron-based permanent-magnet materials Type A1 Journal article
Year 2021 Publication Physical Review Applied Abbreviated Journal Phys Rev Appl
Volume 15 Issue 2 Pages 024012
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Permanent magnets generally require a favorable, but difficult-to-achieve combination of high magnetization, Curie point, and magnetic anisotropy. Thus there have been few, if any, viable permanent magnets developed since the 1982 discovery of Nd2Fe14B [M. Sagawa, S. Fujimura, H. Yamamoto, Y. Matsuura, and S. Hirosawa, J. Appl. Phys. 57, 4094 (1985)]. Here we point out, both by direct first-principles calculations on the iron carbides and silicides Fe5C2, Fe5SiC, and Fe7C3 as well as a discussion of recent experimental findings, that there are numerous rare-earth-free iron-rich potential permanent-magnet materials with sufficient intrinsic magnetic properties to reasonably achieve room-temperature energy products of 20-25 MG Oe. This is substantially better than the performance of the best available rare-earth-free magnets based on ferrite, as well as shape-anisotropy-employing alnico. These magnets could plausibly fill, at low cost, the present performance “gap” [J. M. D. Coey, Scr. Mater. 67, 524 (2012)] between the best rare-earth-free magnets and rare-earth magnets such as Nd2Fe14B and Sm-Co.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000614707800002 Publication Date 2021-02-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2331-7019 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.808 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.808
Call Number UA @ admin @ c:irua:176624 Serial 6734
Permanent link to this record
 
 
Author Sethu, K.K.V.; Ghosh, S.; Couet, S.; Swerts, J.; Sorée, B.; De Boeck, J.; Kar, G.S.; Garello, K.
Title Optimization of tungsten beta-phase window for spin-orbit-torque magnetic random-access memory Type A1 Journal article
Year 2021 Publication Physical Review Applied Abbreviated Journal Phys Rev Appl
Volume 16 Issue 6 Pages 064009
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Switching induced by spin-orbit torque (SOT) is being vigorously explored, as it allows the control of magnetization using an in-plane current, which enables a three-terminal magnetic-tunnel-junction geometry with isolated read and write paths. This significantly improves the device endurance and the read stability, and allows reliable subnanosecond switching. Tungsten in the beta phase, beta-W, has the largest reported antidamping SOT charge-to-spin conversion ratio (theta(AD) approximate to -60%) for heavy metals. However, beta-W has a limitation when one is aiming for reliable technology integration: the beta phase is limited to a thickness of a few nanometers and enters the alpha phase above 4 nm in our samples when industry-relevant deposition tools are used. Here, we report our approach to extending the range of beta-W, while simultaneously improving the SOT efficiency by introducing N and O doping of W. Resistivity and XRD measurements confirm the extension of the beta phase from 4 nm to more than 10 nm, and transport characterization shows an effective SOT efficiency larger than -44.4% (reaching approximately -60% for the bulk contribution). In addition, we demonstrate the possibility of controlling and enhancing the perpendicular magnetic anisotropy of a storage layer (Co-Fe-B). Further, we integrate the optimized W(O, N) into SOT magnetic random-access memory (SOT-MRAM) devices and project that, for the same thickness of SOT material, the switching current decreases by 25% in optimized W(O, N) compared with our standard W. Our results open the path to using and further optimizing W for integration of SOT-MRAM technology.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000729005800002 Publication Date 2021-12-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2331-7019 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.808 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.808
Call Number UA @ admin @ c:irua:184832 Serial 7007
Permanent link to this record
 
 
Author Tao, Z.H.; Dong, H.M.; Milošević, M.V.; Peeters, F.M.; Van Duppen, B.
Title Tailoring dirac plasmons via anisotropic dielectric environment by design Type A1 Journal article
Year 2021 Publication Physical Review Applied Abbreviated Journal Phys Rev Appl
Volume 16 Issue 5 Pages 054030
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Dirac plasmons in a two-dimensional (2D) crystal are strongly affected by the dielectric properties of the environment, due to interaction of their electric field lines with the surrounding medium. Using graphene as a 2D reservoir of free carriers, one can engineer a material configuration that provides an anisotropic environment to the plasmons. In this work, we discuss the physical properties of Dirac plasmons in graphene surrounded by an arbitrary anisotropic dielectric and exemplify how h-BN-based heterostructures can be designed to bear the required anisotropic characteristics. We calculate how dielec-tric anisotropy impacts the spatial propagation of the plasmons and find that an anisotropy-induced plasmon mode emerges, together with a damping pathway, that stem from the out-of-plane off-diagonal elements in the dielectric tensor. Furthermore, we find that one can create hyperbolic plasmons by inher-iting the dielectric hyperbolicity of the designed material environment. Strong control over plasmon propagation patterns can be realized in a similar manner. Finally, we show that in this way one can also control the polarization of the light-matter excitations that constitute the plasmon. Taken together, our results promote the design of the dielectric environment as an effective path to tailor the plasmonic response of graphene on the nanoscopic level.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000720372500002 Publication Date 2021-11-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2331-7019 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.808 Times cited 1 Open Access Not_Open_Access
Notes Approved Most recent IF: 4.808
Call Number UA @ admin @ c:irua:184063 Serial 7028
Permanent link to this record
 
 
Author Saqlain, M.A.; Hussain, A.; Siddiq, D.M.; Leenaerts, O.; Leitão, A.A.
Title DFT Study of Synergistic Catalysis of the Water-Gas-Shift Reaction on Cu-Au Bimetallic Surfaces Type A1 Journal article
Year 2016 Publication ChemCatChem Abbreviated Journal Chemcatchem
Volume 8 Issue 8 Pages 1208-1217
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The water-gas-shift reaction (WGSR) is an important industrial process that can be significantly enhanced at suitable catalyst surfaces. In this work, we investigate the catalytic behavior of metallic Cu(1 0 0) and bimetallic Cu–Au(1 0 0) surfaces. With density functional theory calculations, the variation in the Gibbs free energy (ΔG°), the activation barriers, and the rate constants for the WGSR are calculated. The variation in ΔG° for water dissociation shows that the process is spontaneous up to 520 K on the bimetallic surface and up to 229 K on the Cu(1 0 0) surface. The calculated rate constants for the process also show that the bimetallic surface is much more reactive than the Cu(1 0 0) surface. The calculated pressure–temperature phase diagram for water dissociation shows that the partial pressure of H2O required for water dissociation on the bimetallic surface is substantially lower than that on the Cu(1 0 0) surface at all the studied temperatures. Additionally, the calculations demonstrate that the kinetics of the water-gas-shift reaction is dominated by redox processes on both the surfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000373074900026 Publication Date 2016-02-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1867-3880 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.803 Times cited 8 Open Access
Notes ; The authors would like to thank the Brazilian agencies CNPq, CAPES, FAPEMIG (CEX-PPM-00262/13), and TWAS for financial support and CENAPAD-SP for computational facilities. M.A. Saqlain pays special thanks to all the members of GFQSI for making his stay in Brazil memorable. ; Approved Most recent IF: 4.803
Call Number c:irua:133236 Serial 4070
Permanent link to this record
 
 
Author Zhong, R.; Peng, L.; de Clippel, F.; Gommes, C.; Goderis, B.; Ke, X.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F.
Title An eco-friendly soft template synthesis of mesostructured silica-carbon nanocomposites for acid catalysis Type A1 Journal article
Year 2015 Publication ChemCatChem Abbreviated Journal Chemcatchem
Volume 7 Issue 7 Pages 3047-3058
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The synthesis of ordered mesoporous silica-carbon composites was explored by employing TEOS and sucrose as the silica and carbon precursor respectively, and the triblock copolymer F127 as a structure-directing agent via an evaporation-induced self-assembly (EISA) process. It is demonstrated that the synthesis procedures allow for control of the textural properties and final composition of these silica-carbon nanocomposites via adjustment of the effective SiO2/C weight ratio. Characterization by SAXS, N-2 physisorption, HRTEM, TGA, and C-13 and Si-29 solid-state MAS NMR show a 2D hexagonal mesostructure with uniform large pore size ranging from 5.2 to 7.6nm, comprising of separate carbon phases in a continuous silica phase. Ordered mesoporous silica and non-ordered porous carbon can be obtained by combustion of the pyrolyzed nanocomposites in air or etching with HF solution, respectively. Sulfonic acid groups can be readily introduced to such kind of silica-carbon nanocomposites by a standard sulfonation procedure with concentrated sulfuric acid. Excellent acid-catalytic activities and selectivities for the dimerization of styrene to produce 1,3-diphenyl-1-butene and dimerization of -methylstyrene to unsaturated dimers were demonstrated with the sulfonated materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000361189400037 Publication Date 2015-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1867-3880; 1867-3899 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.803 Times cited 13 Open Access
Notes Approved Most recent IF: 4.803; 2015 IF: 4.556
Call Number UA @ lucian @ c:irua:127836 Serial 4138
Permanent link to this record
 
 
Author Rafiaani, P.; Kuppens, T.; Thomassen, G.; Van Dael, M.; Azadi, H.; Lebailly, P.; Van Passel, S.
Title A critical view on social performance assessment at company level : social life cycle analysis of an algae case Type A1 Journal article
Year 2020 Publication International Journal Of Life Cycle Assessment Abbreviated Journal Int J Life Cycle Ass
Volume Issue Pages
Keywords A1 Journal article; Engineering Management (ENM)
Abstract Purpose Social indicators are not easy to be quantitatively analyzed, although at the local scale, the social impacts might be relevant and important. Using the existing approaches for both quantitative and semi-qualitative measurements, this study aims to assess the social impacts of a company working on algae production systems in Belgium through social life cycle analysis (SLCA). By highlighting the opportunities and challenges on the way of applying the existing SLCA approaches at company level, the objective of this study is to contribute to the development of a suitable and clear SLCA approach when a company is considered as the unit of analysis. Methods Based on the list of potential social impact categories suggested by the United Nations Environment Program/Society of Environmental Toxicology and Chemistry (UNEP/SETAC) guidelines (2009) for SLCA, three stakeholder groups (workers, consumers, and local community) and three subcategories associated with each stakeholder group were identified as the most relevant for carbon capture and utilization technologies. Company and sector level data were collected using existing documents and reports, and the data were analyzed and scored using a combined quantitative and semi-quantitative approach to develop a social assessment model for the case study. Results and discussion The company appears to perform well for all the evaluated social indicators except the one related to the subcategory “equal opportunity/discrimination for workers” for which the share of women employed is lower compared with the sector-level data. The results of our assessment were further discussed regarding the challenges and limitations of performing SLCA at the company level. Based on our experience, the validity of the outcomes is significantly influenced by the data availability, the generality of the indicators introduced within the UNEP/SETAC guidelines, and the subjectivity in data collection for the semi-quantitative assessment among others. Conclusions By highlighting the difficulties and challenges of applying the SLCA at the company level, our study provides a starting point for improving the quantitative assessment and monitoring social implications at the company level within a regional foreground in Europe.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000492643600001 Publication Date 2019-10-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0948-3349; 1614-7502 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.8 Times cited 1 Open Access
Notes ; ; Approved Most recent IF: 4.8; 2020 IF: 3.173
Call Number UA @ admin @ c:irua:164676 Serial 6141
Permanent link to this record
 
 
Author Gestels, A.; Van der Snickt, G.; Caen, J.; Nuyts, G.; Legrand, S.; Vanmeert, F.; Detry, F.; Janssens, K.; Steenackers, G.
Title Combined MA-XRF, MA-XRPD and SEM-EDX analysis of a medieval stained-glass panel formerly from Notre Dame, Paris reveals its material history Type A1 Journal article
Year 2022 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 177 Issue Pages 107304
Keywords A1 Journal article; Engineering sciences. Technology; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract As part of its conservation-restoration, the 13th century stained-glass panel ‘the Annunciation’, was examined at the micro- and macro level. This window, since 1898 in the collection of the Museum Mayer Van den Bergh (Antwerp, B), was formerly a part of the southern Rose window of the Notre Dame Cathedral (Paris, F). The insigths emerging from a first phase of the analysis, comprising non-invasive analysis techniques such as optical microscopy combined with macroscopic X-ray fluorescence (MA-XRF) and X-ray diffraction (MA-XRPD) mapping, were used to select sampling positions for the second phase of investigation that involved micro-invasive analysis, namely scanning-electron microscopy coupled to energy-dispersive X-ray analysis (SEM-EDX). The aim of the investigation was fourfold: (1) to assess the applicability of MA-XRF scanning for the characterisation of stained glass windows prior to any conservation or restoration procedure, (2) to assess the applicability of MA-XRPD scanning to identify the degradation products formed on the surface of stained glass windows, (3) to establish a method to limit the set of sampled glass fragments taken from a glass panel for quantititive analysis while maintaining sufficient representativeness and (4) to distinguish the original glass panes and grisaille paint from non-original glass panes that were inserted during various past interventions. Most of the panes in this window proved to consist of medieval potash glass, consistent with the 13th c. origin of the window while a limited number of panes were identified as non-original infills, with divergent glass compositional types and/or colorants. Most panes derive their color from the pot metal glass (i.e. homogenously colored) they were made of. Some of the panes that originally had a red flashed layer on their surface, completely or partially lost this layer due to weathering. Three main compositional glass families with similar color could be defined. With the exception of the yellow and orange panes, the chromophoric elements responsible for the dark(er) and light(er) blue (Co), green (Cu), purple (Mn) and red colors (Cu) were identified. Two different grisaille paints were encountered, part of which were restored during the 19th century. On the basis of this information, all missing pieces were replaced by glass panes with appropriate colors and the panel could be successfully conserved to its former glory. On the surface of several panes, typical glass degradation products such as calcite, syngenite and gypsum were identified, together with lead based degradation products such as anglesite and palmierite. In addition, the presence of hematite and melanotekite in the grisailles was observed; also the presence of Zn, uncorrelated to Cu, in the grissailes on the right side of the window became apparent.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000850000900001 Publication Date 2022-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.8
Call Number UA @ admin @ c:irua:187493 Serial 7138
Permanent link to this record
 
 
Author Fabri, C.; Moretti, M.; Van Passel, S.
Title On the (ir)relevance of heatwaves in climate change impacts on European agriculture Type A1 Journal article
Year 2022 Publication Climatic Change Abbreviated Journal Climatic Change
Volume 174 Issue 1-2 Pages 16-20
Keywords A1 Journal article; Engineering Management (ENM)
Abstract The Ricardian model is a widely used approach based on cross-sectional regression analysis to estimate climate change impacts on agricultural productivity. Up until now, researchers have focused on the impacts of gradual changes in temperature and precipitation, even though climate change is known to encompass also changes in the severity and frequency of extreme weather events. This research investigates the impact of heatwaves on European agriculture, additional to the impact of average climate change. Using a dataset of more than 60,000 European farms, the study examines whether adding a measure for heatwaves to the Ricardian model influences its results. We find that heatwaves have a minor impact on agricultural productivity and that this impact is moderated by average temperature. In colder regions, farm productivity increases with the number of heatwave days. For warmer regions, land values decrease with heatwave frequency. Despite the moderating effect, the marginal effect of heatwave frequency, i.e. the percentage change in agricultural land values caused by one more heatwave day per year, is small in comparison to the effect of average temperature increases. Non-marginal effects are found to be relevant, but only in the case of increased heatwave frequency. According to our results, farms are not expected to suffer more from extreme weather than from mean climate change, as was claimed by several previous studies.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000861873100002 Publication Date 2022-09-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0165-0009; 1573-1480 ISBN Additional Links UA library record; WoS full record
Impact Factor (down) 4.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.8
Call Number UA @ admin @ c:irua:191483 Serial 7364
Permanent link to this record
 
 
Author Álvarez-Martín, A.; De Winter, S.; Nuyts, G.; Hermans, J.; Janssens, K.; van der Snickt, G.
Title Multi-modal approach for the characterization of resin carriers in Daylight Fluorescent Pigments Type A1 Journal article
Year 2020 Publication Microchemical Journal Abbreviated Journal Microchem J
Volume 159 Issue Pages 105340
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Almost seventy years after artists such as Frank Stella (1936), Andy Warhol (1928-1987), James Rosenquist (1933-2017), Herb Aach (1923-1985) and Richard Bowman (1918-2001) started to incorporate Daylight Fluorescent Pigments (DFPs) in their artworks, the extent of the conservation problems that are associated with these pigments has increased progressively. Since their first appearance on the market, their composition has constantly been improved in terms of permanency. However, conservation practices on the artworks that are used in, are complicated by the fact that the composition of DFPs is proprietary and the information provided by the manufactures is limited. To be able to propose adequate conservation strategies for artworks containing DFPs, a thorough understanding of the DFPs composition must be acquired. In contrast with previous research that concentrated on identification of the coloring dye, this paper focuses on the characterization of the resin, used as the carrier for the dye. The proposed approach, involving ATR-FTIR, SPME-GC-MS and XRF analysis, provided additional insights on the organic and inorganic components of the resin. Using this approach, we investigated historical DFPs and new formulations, as well as different series from the main manufacturing companies (DayGlo, Swada, Radiant Color and Kremer) in order to obtain a full characterization of DFPs used by the artists along the years. First, the initial PCA-assisted ATR-FTIR spectroscopy allowed for an efficient classification of the main monomers in the resin polymer. Next, a further distinction was made by mass spectrometry and XRF which were optimized to allow a more specific classification of the resin and for detection of additives. In this paper we show the potential of SPME-GC-MS, never applied for the characterization of artistic materials, at present undervalued for heritage science purposes. We anticipate that this information will be highly relevant in the future stability studies and for defining (preventive) conservation strategies of fluorescent artworks.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000598761400009 Publication Date 2020-07-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.8 Times cited Open Access
Notes Approved Most recent IF: 4.8; 2020 IF: 3.034
Call Number UA @ admin @ c:irua:175083 Serial 8286
Permanent link to this record
 
 
Author Drăgan, A.-M.; Parrilla, M.; Cambré, S.; Domínguez-Robles, J.; Detamornrat, U.; Donnelly, R.F.; Oprean, R.; Cristea, C.; De Wael, K.
Title Microneedle array-based electrochemical sensor functionalized with SWCNTs for the highly sensitive monitoring of MDMA in interstitial fluid Type A1 Journal article
Year 2023 Publication Microchemical journal Abbreviated Journal
Volume 193 Issue Pages 109257-11
Keywords A1 Journal article; Pharmacology. Therapy; Nanostructured and organic optical and electronic materials (NANOrOPT); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract Illicit drug consumption constitutes a great concern worldwide due to its increased spread and abuse, and the negative consequences exerted on society. For instance, 3,4-methylenedioxymethamphetamine (MDMA), a synthetic amphetamine-type substance, was abused by 20 million people worldwide in 2020. This psychoactive substance exerts a myriad of effects on the human body being dangerous for the consumer’s health. Besides, MDMA has been used in the treatment of some psychiatric conditions. Therefore, the development of wearable devices for MDMA sensing in biological fluids is of great importance for forensic toxicology (e.g., monitoring of patients with suspected or known MDMA consumption) as well as for therapeutic management of patients. Herein, we report the development of a wearable electrochemical platform based on a hollow microneedle (MN) array sensor for the monitoring of MDMA in the interstitial fluid by square-wave voltammetry. First, the holes of the MN array were modified with conductive pastes to devise a MN patch with a three-electrode system. Subsequently, the functionalization of the working electrode with nanomaterials enhanced MDMA detection. Thereafter, analytical parameters were evaluated exhibiting a slope of 0.05 µA µM−1 within a linear range from 1 to 50 µM and a limit of detection of 0.75 µM in artificial interstitial fluid. Importantly, critical parameters such as selectivity, piercing capability, temperature, reversibility and stability were assessed. Overall, the obtained MN sensor exhibited excellent analytical performance, making it a promising tool for MDMA tracking in interstitial fluid for individuals on probation or under therapeutic treatment.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001067945900001 Publication Date 2023-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.8 Times cited Open Access Not_Open_Access: Available from 27.02.2024
Notes Approved Most recent IF: 4.8; 2023 IF: 3.034
Call Number UA @ admin @ c:irua:198183 Serial 8898
Permanent link to this record
 
 
Author Truta, F.; Cruz, A.G.; Tertis, M.; Zaleski, C.; Adamu, G.; Allcock, N.S.; Suciu, M.; Stefan, M.-G.; Kiss, B.; Piletska, E.; De Wael, K.; Piletsky, S.A.; Cristea, C.
Title NanoMIPs-based electrochemical sensors for selective detection of amphetamine Type A1 Journal article
Year 2023 Publication Microchemical journal Abbreviated Journal
Volume 191 Issue Pages 108821-10
Keywords A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract A highly sensitive and portable electrochemical sensor based on molecularly imprinted nanoparticles (nanoMIPs) was developed. NanoMIPs were computationally designed for specific recognition of amphetamine, and then synthetized using solid phase synthesis. NanoMIPs were immobilized onto screen-printed carbon electrodes using a composite film comprising chitosan, nanoMIPs, and graphene oxide.Ferrocenylmethyl methacrylate was incorporated in nanoMIPs allowing electrochemical detection. The signal recorded for the electrochemical oxidation of ferrocene has proven to be dependent on the presence of amphetamine interacting with nanMIPs. The sensor was tested successfully with street samples, with high sensitivity and satisfactory recoveries (from 100.9% to 107.6%). These results were validated with UPL-MS/MS. The present technology is suitable for forensic applications in selective determination of amphetamine in street samples.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001008428600001 Publication Date 2023-05-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.8 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.8; 2023 IF: 3.034
Call Number UA @ admin @ c:irua:197397 Serial 8903
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Author Van Echelpoel, R.; Parrilla, M.; Sleegers, N.; Thiruvottriyur Shanmugam, S.; van Nuijs, A.L.N.; Slosse, A.; Van Durme, F.; De Wael, K.
Title Validated portable device for the qualitative and quantitative electrochemical detection of MDMA ready for on-site use Type A1 Journal article
Year 2023 Publication Microchemical journal Abbreviated Journal
Volume 190 Issue Pages 108693-10
Keywords A1 Journal article; Engineering sciences. Technology; Toxicological Centre; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract Identifying and quantifying 3,4-methyl​enedioxy​methamphetamine (MDMA) on-site in suspected illicit drug samples, whether it be at recreational settings or manufacturing sites, is a major challenge for law enforcement agencies (LEAs). Various analytical techniques exist to fulfil this goal, e.g. colourimetry and portable spectroscopic techniques, each having its specific limitations (e.g. low accuracy, fluorescence, no quantification) and strengths (e.g. fast, easy to use). In this work, for the first time, an electrochemical MDMA sensor is presented to become a detection tool that can realistically be used on-site. More specifically, the use of a single buffer solution and an unmodified screen-printed electrode, along with the integration of a data analysis algorithm and mobile application permits the straightforward on-site identification and quantification of MDMA in suspicious samples. Multiple studies investigating different parameters, including pH, concentration, reproducibility, temperature and binary mixture analyses, were executed. To fully understand all the occurring redox processes, liquid chromatography coupled with high-resolution mass spectrometry analysis of partially electrolyzed MDMA samples was performed unravelling oxidation of the methylenedioxy group. Validation of the methodology was executed on 15 MDMA street samples analysed by gas chromatography coupled with mass spectrometry and compared with the performance of a commercial portable Raman and Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) device. The novel methodology outperformed the spectroscopic techniques, correctly identifying all 15 street samples. Additionally, the electrochemical sensor predicted the purity of the tablets with a mean absolute error of 2.3%. Overall, this new, electrochemical detection strategy provides LEAs the rapid, low-cost, on-site detection and quantification of MDMA in suspicious samples, without requiring specialized training.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000977060400001 Publication Date 2023-03-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.8 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.8; 2023 IF: 3.034
Call Number UA @ admin @ c:irua:195415 Serial 8952
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Author Pastorelli, G.; Miranda, A.S.O.; Avranovich Clerici, E.; d'Imporzano, P.; Hansen, B.V.; Janssens, K.; Davies, G.R.; Borring, N.
Title Darkening of lead white in old master drawings and historic prints : a multi-analytical investigation Type A1 Journal article
Year 2024 Publication Microchemical journal Abbreviated Journal
Volume 199 Issue Pages 109912-10
Keywords A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract Old master drawings and historic prints often feature white highlights, which are typically painted using lead white, one of the most widely used historical white pigments. However, it has been observed that many of these highlights discolour over time, becoming dark brown or black due to unclear degradation processes. This phenomenon not only misrepresents the original artefacts, threatening their suitability for public display, but also diminishes their longevity. To ensure their preservation, it is essential to determine why some lead white highlights in these museum objects retain their light tones while others are prone to darkening. The objective of this study was to identify the relationships between the composition, provenance, and production methods of lead white pigments, and their role in the discolouration observed on drawings, lithographs and early photographs. Selected samples and artefacts were examined using a range of analytical techniques, namely X-ray fluorescence spectroscopy (XRF), X-ray powder diffraction (XRPD), and lead isotope analysis. While XRF analyses confirmed the presence of lead as the primary element in the majority of the highlights, XRPD measurements identified a variety of lead compounds such as the carbonates cerussite and hydrocerussite alongside galena-a black crystalline sulfide-and lead sulfates. Additionally, isotope analyses classified the lead raw materials into five main groups. Through these measurements, the examined lead white pigments were categorised based on their compositional properties in relation to the raw materials used, as well as their geographical and temporal origin. A significant finding is that lead white pigments from different production periods, spanning from older to more modern, may be characterised by varying proneness to discolouration irrespective of their provenance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001166502200001 Publication Date 2024-01-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record
Impact Factor (down) 4.8 Times cited Open Access
Notes Approved Most recent IF: 4.8; 2024 IF: 3.034
Call Number UA @ admin @ c:irua:205450 Serial 9197
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Author Vallicrosa, H.; Lugli, L.F.; Fuchslueger, L.; Sardans, J.; Ramirez-Rojas, I.; Verbruggen, E.; Grau, O.; Brechet, L.; Peguero, G.; Van Langenhove, L.; Verryckt, L.T.; Terrer, C.; Llusia, J.; Ogaya, R.; Marquez, L.; Roc-Fernandez, P.; Janssens, I.; Penuelas, J.
Title Phosphorus scarcity contributes to nitrogen limitation in lowland tropical rainforests Type A1 Journal article
Year 2023 Publication Ecology Abbreviated Journal
Volume 104 Issue 6 Pages e4049-12
Keywords A1 Journal article; Plant and Ecosystems (PLECO) – Ecology in a time of change
Abstract There is increasing evidence to suggest that soil nutrient availability can limit the carbon sink capacity of forests, a particularly relevant issue considering today's changing climate. This question is especially important in the tropics, where most part of the Earth's plant biomass is stored. To assess whether tropical forest growth is limited by soil nutrients and to explore N and P limitations, we analyzed stem growth and foliar elemental composition of the five stem widest trees per plot at two sites in French Guiana after 3 years of nitrogen (N), phosphorus (P), and N + P addition. We also compared the results between potential N-fixer and non-N-fixer species. We found a positive effect of N fertilization on stem growth and foliar N, as well as a positive effect of P fertilization on stem growth, foliar N, and foliar P. Potential N-fixing species had greater stem growth, greater foliar N, and greater foliar P concentrations than non-N-fixers. In terms of growth, there was a negative interaction between N-fixer status, N + P, and P fertilization, but no interaction with N fertilization. Because N-fixing plants do not show to be completely N saturated, we do not anticipate N providing from N-fixing plants would supply non-N-fixers. Although the soil-age hypothesis only anticipates P limitation in highly weathered systems, our results for stem growth and foliar elemental composition indicate the existence of considerable N and P co-limitation, which is alleviated in N-fixing plants. The evidence suggests that certain mechanisms invest in N to obtain the scarce P through soil phosphatases, which potentially contributes to the N limitation detected by this study.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000977760600001 Publication Date 2023-04-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0012-9658; 1939-9170 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.8 Times cited Open Access
Notes Approved Most recent IF: 4.8; 2023 IF: 4.809
Call Number UA @ admin @ c:irua:196804 Serial 9218
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Author Drozhzhin, O.A.; Vorotyntsev, M.A.; Maduar, S.R.; Khasanova, N.R.; Abakumov, A.M.; Antipov, E.V.
Title Li-ion diffusion in LixNb9PO25 Type A1 Journal article
Year 2013 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 89 Issue Pages 262-269
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Wadsley-Roth phase LixNb6PO25 has been studied as a potential candidate for anode material of Li-ion batteries. Its crystal structure, which consists of ReO3-type blocks of NbO6 octahedra connected with PO4 tetrahedra, provides a good stability and performance during Li+ insertion/removal. Li-ion chemical diffusion coefficient (D-chem) in LixNb6PO25 was determined by means of potentiostatic intermittent titration technique and electrochemical impedance spectroscopy. Different data treatments (classical Warburg equation or the model of an electrode system with ohmic potential drop and/or slow kinetics of the interfacial Li+ ion transfer across the electrode/electrolyte interface) were used for calculation of D-chem of the Li ion inside this material; their applicability is discussed in the article. D-chem changes with the Li-ion doping degree, x, in LixNb3PO25 and has a sharp minimum near the two-phase region at appr. 1.7V vs. Li+/Li. These values of D-chem in LixNb9PO25 (similar to 10(-9)-10(-11) cm(2) s(-1)) were found to be in average noticeably higher than in the widely studied anode material, Li4Ti5O12. (C) 2012 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000315558200034 Publication Date 2012-11-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 11 Open Access
Notes Approved Most recent IF: 4.798; 2013 IF: 4.086
Call Number UA @ lucian @ c:irua:108312 Serial 1816
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Author Radvanyi, E.; Van Havenbergh, K.; Porcher, W.; Jouanneau, S.; Bridel, J.-S.; Put, S.; Franger, S.
Title Study and modeling of the Solid Electrolyte Interphase behavior on nano-silicon anodes by Electrochemical Impedance Spectroscopy Type A1 Journal article
Year 2014 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 137 Issue Pages 751-757
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The instability of the Solid Electrolyte Interphase (SEI) at the surface of nano-silicon electrodes has been recognized as one of the key issues to explain the rapid capacity fading of theses electrodes. In this paper, two distinct Si-based systems are studied by using Electrochemical Impedance Spectroscopy (EIS). First, several EIS spectra are recorded along the second electrochemical cycle. Although the active material, the electrode formulation, and the experimental conditions are different for the two systems, the same phenomena are observed in both cases: (i) the SEI deposit around 50 kHz, (ii) the charge transfer (CT) with a characteristic frequency varying from 300 to 1 500 Hz, and (iii) an inductive loop at ∼1 Hz which appears only when the potential of the electrode is below 0.35 V vs Li. As the latter has never been reported for Si-based electrodes, the second step of the work consists in understanding this phenomenon. Thanks to the results obtained in a set of several complementary experiments, we finally attribute the inductive loop to the constant formation/deposition of SEI products, in competition with the CT process. In addition, we propose a mechanism for this specific phenomenon and the equivalent circuit to fit the recorded EIS spectra.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000341462500095 Publication Date 2014-06-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 36 Open Access
Notes IWT (K. Van Havenbergh) Approved Most recent IF: 4.798; 2014 IF: 4.504
Call Number UA @ lucian @ c:irua:117945 Serial 3323
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Author Drozhzhin, O.A.; Sumanov, V.D.; Karakulina, O.M.; Abakumov, A.M.; Hadermann, J.; Baranov, A.N.; Stevenson, K.J.; Antipov, E.V.
Title Switching between solid solution and two-phase regimes in the Li1-xFe1-yMnyPO4 cathode materials during lithium (de)insertion: combined PITT, in situ XRPD and electron diffraction tomography study Type A1 Journal article
Year 2016 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 191 Issue 191 Pages 149-157
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The electrochemical properties and phase transformations during (de)insertion of Li+ in LiFePO4, LiFe0.9Mn0.1PO4 and LiFe0.5Mn0.5PO4 are studied by means of galvanostatic cycling, potential intermittent titration technique (PITT) and in situ X-ray powder diffraction. Different modes of switching between the solid solution and two-phase regimes are revealed which are influenced by the Mn content in Li1-xFe1-yMnyPO4. Additionally, an increase in electrochemical capacity with the Mn content is observed at high rates of galvanostatic cycling (10C, 20C), which is in good agreement with the numerically estimated contribution of the solid solution mechanism determined from PITT data. The observed asymmetric behavior of the phase transformations in Li1-xFe0.5Mn0.5PO4 during charge and discharge is discussed. For the first time, the crystal structures of electrochemically deintercalated Li1-xFe0.5Mn0.5PO4 with different Li content – LiFe0.5Mn0.5PO4, Li0.5Fe0.5Mn0.5PO4 and Li0.1Fe0.5Mn0.5PO4 – are refined, including the occupancy factors of the Li position. This refinement is done using electron diffraction tomography data. The crystallographic analyses of Li1-xFe0.5Mn0.5PO4 reveal that at x = 0.5 and 0.9 the structure retains the Pnma symmetry and the main motif of the pristine x = 0 structure without noticeable short range order effects.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000371143200018 Publication Date 2016-01-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 27 Open Access
Notes This work was supported by the Russian Foundation of Basic Research (grants No. 14-29-04064 and 14-03-31473), Skolkovo Institute of Science and Technology, and the Lomonosov Moscow State University Program of Development. J. Hadermann, O. M. Karakulina and A. M. Abakumov acknowl- edge support from FWO under grant G040116N. Approved Most recent IF: 4.798
Call Number c:irua:131911 Serial 4032
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Author Vanrenterghem, B.; Papaderakis, A.; Sotiropoulos, S.; Tsiplakides, D.; Balomenou, S.; Bals, S.; Breugelmans, T.
Title The reduction of benzylbromide at Ag-Ni deposits prepared by galvanic replacement Type A1 Journal article
Year 2016 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 196 Issue 196 Pages 756-768
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract A two-step procedure was applied to prepare bimetallic Ag-Ni glassy carbon supported catalysts (Ag-Ni/GC). First Ni layers were prepared by means of electrodeposition in an aqueous deaerated nickel chloride + nickel sulfamate + boric acid solution. Second, the partial replacement of Ni layers by Ag was achieved upon immersion of the latter in solutions containing silver nitrate. Three different pretreatment protocols were used after preparation of the Ag/Ni deposits; as prepared, cathodised in alkali and scanned in acid. After the pretreatment the surface was characterised by means of spectroscopy techniques (scanning electron microscopy and energy dispersive x-ray) and electrochemically in an alkali NaOH solution through cyclic voltammetry (CV). Afterwards the modified electrodes were tested for the reduction of benzylbromide in acetonitrile solutions by using CV and were found to show improved activity compared to bulk Ag electrode. The highest activity towards benzylbromide reduction was observed for pre-cathodised Ag-Ni electrodes. A final stage of the research focuses on the development of a practical Ag/Ni foam catalyst for the reduction of benzylbromide. Due to the high electrochemical active surface area of Ag/Ni foam, a higher conversion of benzyl bromide was obtained in comparison with bulk Ag.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000372877400083 Publication Date 2016-03-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 21 Open Access OpenAccess
Notes The quanta 250 FEG microscope of the Electron Microscopy for Material Science group at the University of Antwerp was funded by the Hercules foundation of the Flemish government. Sara Bals acknowledges financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS).; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); Approved Most recent IF: 4.798
Call Number c:irua:132081 Serial 4065
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Author Ryabova, A.S.; Napolskiy, F.S.; Poux, T.; Istomin, S.Y.; Bonnefont, A.; Antipin, D.M.; Baranchikov, A.Y.; Levin, E.E.; Abakumov, A.M.; Kéranguéven, G.; Antipov, E.V.; Tsirlina, G.A.; Savinova, E.R.;
Title Rationalizing the influence of the Mn(IV)/Mn(III) red-Ox transition on the electrocatalytic activity of manganese oxides in the oxygen reduction reaction Type A1 Journal article
Year 2016 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 187 Issue 187 Pages 161-172
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Knowledge on the mechanisms of oxygen reduction reaction (ORR) and descriptors linking the catalytic activity to the structural and electronic properties of transition metal oxides enable rational design of more efficient catalysts. In this work ORR electrocatalysis was studied on a set of single and complex Mn (III) oxides with a rotating disc electrode method and cyclic voltammetry. We discovered an exponential increase of the specific electrocatalytic activity with the potential of the surface Mn(IV)/Mn(III) red-ox couple, suggesting the latter as a new descriptor for the ORR electrocatalysis. The observed dependence is rationalized using a simple mean-field kinetic model considering availability of the Mn( III) centers and adsorbate-adsorbate interactions. We demonstrate an unprecedented activity of Mn2O3, ca. 40 times exceeding that of MnOOH and correlate the catalytic activity of Mn oxides to their crystal structure. (C) 2015 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000367235600019 Publication Date 2015-11-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 51 Open Access
Notes Approved Most recent IF: 4.798
Call Number UA @ lucian @ c:irua:131096 Serial 4237
Permanent link to this record
 
 
Author Deshmukh, S.; Sankaran, K.J.; Korneychuk, S.; Verbeeck, J.; Mclaughlin, J.; Haenen, K.; Roy, S.S.
Title Nanostructured nitrogen doped diamond for the detection of toxic metal ions Type A1 Journal article
Year 2018 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 283 Issue 283 Pages 1871-1878
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract This work demonstrates the applicability of one-dimensional nitrogen-doped diamond nanorods (N-DNRs) for the simultaneous electrochemical (EC) detection of Pb2+ and Cd2+ ions in an electrolyte solution. Well separated voltammetric peaks are observed for Pb2+ and Cd2+ ions using N-DNRs as a working electrode in square wave anodic stripping voltammetry measurements. Moreover, the cyclic voltammetry response of N-DNR electrodes towards the Fe(CN)(6)(/4-)/Fe(CN)(6)(/3-) redox reaction is better as compared to undoped DNR electrodes. This enhancement of EC performance in N-DNR electrodes is accounted by the increased amount of sp(2) bonded nanographitic phases, enhancing the electrical conductivity at the grain boundary (GB) regions. These findings are supported by transmission electron microscopy and electron energy loss spectroscopy studies. Consequently, the GB defect induced N-DNRs exhibit better adsorption of metal ions, which makes such samples promising candidates for next generation EC sensing devices. (C) 2018 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000441077900203 Publication Date 2018-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 22 Open Access
Notes Sujit Deshmukh indebted to Shiv Nadar University for providing Ph. D. scholarship. The FEI Quanta SEM and Qu-Ant-EM microscope used for the TEM experiments was partly funded by the Hercules fund from the Flemish Government. S. K. and J. V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. Kamatchi Jothiramalingam Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). Prof. Ken Haenen acknowledges the Methusalem “NANO” network for financial support. Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:153072 Serial 5366
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Author Lybaert, J.; Maes, B.U.W.; Tehrani, K.A.; De Wael, K.
Title The electrochemistry of tetrapropylammonium perruthenate, its role in the oxidation of primary alcohols and its potential for electrochemical recycling Type A1 Journal article
Year 2015 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 182 Issue Pages 693-698
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)
Abstract The search for strategies aiming at more sustainable (oxidation) reactions has led to the application of electrochemistry for recycling the spent catalyst. In this work, an electrochemical study of the tetrapropylammonium perruthenate catalyst (TPAP) and its activity towards a primary alcohol, n-butanol, has been carried out as well as a control study with tert-butanol. The redox chemistry of TPAP and the transition between the perruthenate anion and ruthenium tetroxide in a non-aqueous solvent have been, for the first time, investigated in depth. The oxidation reaction of n-butanol in the presence of TPAP has been electrochemically elucidated by performing potentiostatic experiments and registration of the corresponding oxidation current. Furthermore, it was shown that, by applying a specific potential, the reoxidized TPAP is able to oxidize/convert the primary alcohol, paving the way for practical applications using TPAP in electrochemical synthesis. The conversion of n-butanol into n-butanal was proven by the use of GC-MS.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000365075800084 Publication Date 2015-09-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 2 Open Access
Notes ; ; Approved Most recent IF: 4.798; 2015 IF: 4.504
Call Number UA @ admin @ c:irua:127676 Serial 5599
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Author Pauwels, D.; Ching, H.Y.V.; Samanipour, M.; Neukermans, S.; Hereijgers, J.; Van Doorslaer, S.; De Wael, K.; Breugelmans, T.
Title Identifying intermediates in the reductive intramolecular cyclisation of allyl 2-bromobenzyl ether by an improved electron paramagnetic resonance spectroelectrochemical electrode design combined with density functional theory calculations Type A1 Journal article
Year 2018 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 271 Issue 271 Pages 10-18
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
Abstract The electrochemical activation of C-X bonds requires very negative electrode potentials. Lowering the overpotentials and increasing the catalytic activity requires intensive electrocatalytic research. A profound understanding of the reaction mechanism and the influence of the electrocatalyst allows optimal tuning of the electrocatalyst. This can be achieved by combining electrochemical techniques with electron paramagnetic resonance (EPR) spectroscopy. Although this was introduced in the mid-twentieth century, the application of this combined approach in electrocatalytic research is underexploited. Several reasons can be listed, such as the limited availability of EPR instrumentation and electrochemical devices for such in situ experiments. In this work, a simple and inexpensive construction adapted for in situ EPR electrocatalytic research is proposed. The proof of concept is provided by studying a model reaction, namely the reductive cyclisation of allyl 2-bromobenzyl ether which has interesting industrial applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430369800002 Publication Date 2018-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 2 Open Access
Notes ; The authors would like to thank Melissa Van Landeghem for her assistance with the experimental work and analysis of the data. Jonas Hereijgers greatly acknowledges the Research Foundation Flanders (FWO) for support through a Post-Doctoral grant (12Q8817N). H.Y. Vincent Ching gratefully acknowledges the University of Antwerp for a Post-Doctoral grant. Sabine Van Doorslaer and Tom Breugelmans acknowledge the FWO for research funding (research grant G093317N). ; Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:150463 Serial 5652
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Author Lybaert, J.; Tehrani, K.A.; De Wael, K.
Title Mediated electrolysis of vicinal diols by neocuproine palladium catalysts Type A1 Journal article
Year 2017 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 247 Issue Pages 685-691
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY)
Abstract Synthetic electrochemistry agrees well with the principles of sustainable chemistry, therefore it is considered as a more environmentally friendly approach than some current synthetic methods Here, we present a new strategy for the chemoselective oxidation of vicinal diols, viz. the integration of neocuproine palladium catalysts and electrosynthesis. Benzoquinones are used as an effective mediator as the reduced species (hydroquinones) can be easily reoxidized at relative low potentials at an electrode surface. NeocuproinePd(OAc)2 efficiently works as a catalyst in an electrolysis reaction for vicinal diols at room temperature. This is a remarkable observation given the fact that aerobic oxidation reactions of alcohols typically need a more complex catalyst, i.e. [neocuproinePdOAc]2[OTf]2. In this article we describe the optimization of the electrolysis conditions for the neocuproinePd(OAc)2 catalyst to selectively oxidize diols. The suggested approach leads to conversion of alcohols with high yields and provides an interesting alternative to perform oxidation reactions under mild conditions by the aid of electrochemistry.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000408582300072 Publication Date 2017-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited Open Access
Notes ; ; Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:144118 Serial 5706
Permanent link to this record
 
 
Author Gaetani, C.; Gheno, G.; Borroni, M.; De Wael, K.; Moretto, L.M.; Ugo, P.
Title Nanoelectrode ensemble immunosensing for the electrochemical identification of ovalbumin in works of art Type A1 Journal article
Year 2019 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 312 Issue 312 Pages 72-79
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This research is aimed to the study and application of an electrochemical immunosensor for the detection of ovalbumin (OVA) from egg white (or albumen) used as a binder in some works of art, such as some historical photographic prints and tempera paintings. The immunosensor takes advantage of the interesting biodetection capabilities offered by nanoelectrode ensembles (NEEs). The NEEs used to this aim are prepared by template deposition of gold nanoelectrodes within the pores of track-etched polycarbonate (PC) membranes. The affinity of polycarbonate for proteins is exploited to capture OVA from the aqueous extract obtained by incubation in phosphate buffer of a small sample fragment (<1 mg). The captured protein is reacted selectively with anti-OVA antibody, labelled with glucose oxidase (GOx). In the case of positive response, the addition of the GOx substrate (i.e. glucose) and a suitable redox mediator (a ferrocenyl derivative) reflects in the up rise of an electrocatalytic oxidation current, which depends on the OVA amount captured on the NEE, this amount correlating with OVA concentration in the extract. After optimization, the sensor is successfully applied to identify OVA in photographic prints dating back to the late 19th century, as well as in ancient tempera paintings from the 15th and 18th centuries.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000468595500008 Publication Date 2019-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited 2 Open Access
Notes ; ; Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:159573 Serial 5743
Permanent link to this record
 
 
Author Ryabova, A.S.; Istomin, S.Y.; Dosaev, K.A.; Bonnefont, A.; Hadermann, J.; Arkharova, N.A.; Orekhov, A.S.; Sena, R.P.; Saveleva, V.A.; Kerangueven, G.; Antipov, E., V.; Savinova, E.R.; Tsirlina, G.A.
Title Mn₂O₃ oxide with bixbyite structure for the electrochemical oxygen reduction reaction in alkaline media : highly active if properly manipulated Type A1 Journal article
Year 2021 Publication Electrochimica Acta Abbreviated Journal Electrochim Acta
Volume 367 Issue Pages 137378
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We consider compositional and structural factors which can affect the activity of bixbyite alpha-Mn2O3 towards the oxygen reduction reaction (ORR) and the stability of this oxide in alkaline solution. We compare electrochemistry of undoped, Fe and Al-doped alpha-Mn2O3 with bixbyite structure and braunite Mn7SiO12 having bixbyite-related crystal structure, using the rotating disk electrode (RDE), the rotating ring-disk electrode (RRDE), and cyclic voltammetry (CV) techniques. All manganese oxides under study are stable in the potential range between the ORR onset and ca. 0.7 V vs. Reversible Hydrogen Electrode (RHE). It is found that any changes introduced in the bixbyite structure and/or composition of alpha-Mn2O3 lead to an activity drop in both the oxygen reduction and hydrogen peroxide reactions in this potential interval. For the hydrogen peroxide reduction reaction these modifications also result in a change in the nature of the rate-determining step. The obtained results confirm that due to its unique crystalline structure undoped alpha-Mn2O3 is the most ORR active (among currently available) Mn oxide catalyst and favor the assumption of the key role of the (111) surface of alpha-Mn2O3 in the very high activity of this material towards the ORR. (C) 2020 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000607621500013 Publication Date 2020-10-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:176080 Serial 6731
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Author Stefan, G.; Hosu, O.; De Wael, K.; Jesus Lobo-Castanon, M.; Cristea, C.
Title Aptamers in biomedicine : selection strategies and recent advances Type A1 Journal article
Year 2021 Publication Electrochimica Acta Abbreviated Journal Electrochim Acta
Volume 376 Issue Pages 137994
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Aptamers have come in the spotlight as bio-mimetic molecular recognition elements in the field of biomedicine due to various applications in diagnostics, drug delivery, therapeutics, and pharmaceutical analysis. Aptamers are composed of nucleic acid strands (DNA or RNA) that can specifically interact in a three-dimensional tailored design with the target molecule. The basic method to generate aptamers is Systematic Evolution of Ligands by Exponential Enrichment (SELEX). Recent technological advances in aptamer selection allow for faster and cheaper production of a new generation of high-affinity aptamers compared to the traditional SELEX, which can last up to several months. Rigorous characterization performed by multiple research groups endorsed several well-defined aptamer sequences. Binding affinity, nature of the biomolecular interactions and structural characterization are of paramount importance for aptamer screening and development of applications. However, remarkable challenges still need to be dealt with before the aptamers can make great contributions to the biomedical field. Poor specificity and sensitivity, questionable clinical use, low drug loading, in vivo stability and toxicity are only some of the identified challenges. This review accounts for the 30th celebration of the SELEX technology underlining the most important aptamers' achievements in the biomedical field within mostly the past five years. Aptamers' advantages over antibodies are discussed. Because of potential clinical translational utility, insights of remarkable developments in aptamer-based methods for diagnosis and monitoring of disease biomarkers and pharmaceuticals are discussed focusing on the recent studies (2015-2020). The current challenges and promising opportunities for aptamers for therapeutic and theragnostic purposes are also presented. (C) 2021 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000634761900003 Publication Date 2021-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:177677 Serial 7491
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Author Schram, J.; Thiruvottriyur Shanmugam, S.; Sleegers, N.; Florea, A.; Samyn, N.; van Nuijs, A.L.N.; De Wael, K.
Title Local conversion of redox inactive molecules into redox active ones : a formaldehyde based strategy for the electrochemical detection of illicit drugs containing primary and secondary amines Type A1 Journal article
Year 2021 Publication Electrochimica Acta Abbreviated Journal Electrochim Acta
Volume 367 Issue Pages 137515
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
Abstract Electrochemical techniques have evidenced to be highly suitable for the development of portable, rapid and accurate screening methods for the detection of illicit drugs in seized samples. However, the redox inactivity of primary amines, one of the most common functional groups of illicit drugs, masks voltammetric detection in aqueous environment at carbon electrodes and, therefore, leads to false negative results if only these primary amines are present in the structures. This work explores the feasibility of a derivatisation approach that introduces formaldehyde in the measuring conditions in order to achieve methylation, via an Eschweiler-Clarke mechanism, of illicit drugs containing primary and secondary amines, using amphetamine (AMP) and methamphetamine (MET) as model molecules. As a result the electrochemical fingerprint is enriched and thereby the detectability enhanced. A combination of liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOFMS) and square-wave voltammetric (SWV) measurements is employed to identify reaction products and link them to the observed redox peaks. Although an alkaline environment (pH 12.0) proved to increase the reaction yield, a richer electrochemical fingerprint (EF) is obtained in neutral conditions (pH 7.0). Similarly, the addition of formate improved the reaction conversion but reduced the EF by eliminating a redox peak that is attributed to side products formed in the absence of formate. To illustrate the applicability, the derivatisation strategy is applied to several prominent illicit drugs containing primary and secondary amines to demonstrate its EF enriching capabilities. Finally, real street samples from forensic seizures are analysed. Overall, this strategy unlocks the detectability of the hitherto undetectable AMP and other drugs only containing primary amines, while strongly facilitating the identification of MET and analogues. These findings are not limited to illicit drugs, the insights can ultimately be applied to other target molecules containing similar functional groups. (C) 2020 Published by Elsevier Ltd.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000607620700010 Publication Date 2020-11-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (down) 4.798 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.798
Call Number UA @ admin @ c:irua:176083 Serial 8177
Permanent link to this record