Records |
Author |
Shakouri, K.; Vasilopoulos, P.; Vargiamidis, V.; Hai, G.-Q.; Peeters, F.M. |
Title |
Spin- and valley-dependent commensurability oscillations and electric-field-induced quantum Hall plateaux in periodically modulated silicene |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
104 |
Issue |
21 |
Pages |
213109 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the commensurability oscillations in silicene subject to a perpendicular electric field E-z, a weak magnetic field B, and a weak periodic potential V = V-0 cos(Cy); C = 2 pi/a(0) with a(0) its period. The field E-z and/or the modulation lift the spin degeneracy of the Landau levels and lead to spin and valley resolved Weiss oscillations. The spin resolution is maximal when the field E-z is replaced by a periodic one E-z = E-0 cos(Dy); D = 2 pi/b(0), while the valley one is maximal for b(0) = a(0). In certain ranges of B values, the current is fully spin or valley polarized. Additional quantum Hall conductivity plateaux arise due to spin and valley intra-Landau-level transitions. (C) 2014 AIP Publishing LLC. |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000337143000047 |
Publication Date |
2014-05-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-6951;1077-3118; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
16 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; The work was supported by the Flemish Science Foundation (FWO-VI), the Methusalem Foundation of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756. Also, G. Q. H. was supported by FAPESP and CNPq (Brazil). ; |
Approved |
Most recent IF: 3.411; 2014 IF: 3.302 |
Call Number |
UA @ lucian @ c:irua:118409 |
Serial |
3078 |
Permanent link to this record |
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Author |
Lin, S.-H.; Milošević, M.V.; Covaci, L.; Janko, B.; Peeters, F.M. |
Title |
Quantum rotor in nanostructured superconductors |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
4 |
Issue |
|
Pages |
4542-4546 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Despite its apparent simplicity, the idealized model of a particle constrained to move on a circle has intriguing dynamic properties and immediate experimental relevance. While a rotor is rather easy to set up classically, the quantum regime is harder to realize and investigate. Here we demonstrate that the quantum dynamics of quasiparticles in certain classes of nanostructured superconductors can be mapped onto a quantum rotor. Furthermore, we provide a straightforward experimental procedure to convert this nanoscale superconducting rotor into a regular or inverted quantum pendulum with tunable gravitational field, inertia, and drive. We detail how these novel states can be detected via scanning tunneling spectroscopy. The proposed experiments will provide insights into quantum dynamics and quantum chaos. |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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Language |
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Wos |
000333555300007 |
Publication Date |
2014-04-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2045-2322; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
4 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; The work was supported by the Flemish Science Foundation (FWO-Vl), the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract W-31-109-Eng-38, and the US National Science Foundation via NSF-NIRT ECS-0609249. ; |
Approved |
Most recent IF: 4.259; 2014 IF: 5.578 |
Call Number |
UA @ lucian @ c:irua:116848 |
Serial |
2785 |
Permanent link to this record |
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Author |
Griffin, E.; Mogg, L.; Hao, G.-P.; Kalon, G.; Bacaksiz, C.; Lopez-Polin, G.; Zhou, T.Y.; Guarochico, V.; Cai, J.; Neumann, C.; Winter, A.; Mohn, M.; Lee, J.H.; Lin, J.; Kaiser, U.; Grigorieva, I., V; Suenaga, K.; Ozyilmaz, B.; Cheng, H.-M.; Ren, W.; Turchanin, A.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. |
Title |
Proton and Li-Ion permeation through graphene with eight-atom-ring defects |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Acs Nano |
Abbreviated Journal |
Acs Nano |
Volume |
14 |
Issue |
6 |
Pages |
7280-7286 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Defect-free graphene is impermeable to gases and liquids but highly permeable to thermal protons. Atomic-scale defects such as vacancies, grain boundaries, and Stone-Wales defects are predicted to enhance graphene's proton permeability and may even allow small ions through, whereas larger species such as gas molecules should remain blocked. These expectations have so far remained untested in experiment. Here, we show that atomically thin carbon films with a high density of atomic-scale defects continue blocking all molecular transport, but their proton permeability becomes similar to 1000 times higher than that of defect-free graphene. Lithium ions can also permeate through such disordered graphene. The enhanced proton and ion permeability is attributed to a high density of eight-carbon-atom rings. The latter pose approximately twice lower energy barriers for incoming protons compared to that of the six-atom rings of graphene and a relatively low barrier of similar to 0.6 eV for Li ions. Our findings suggest that disordered graphene could be of interest as membranes and protective barriers in various Li-ion and hydrogen technologies. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000543744100086 |
Publication Date |
2020-05-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
17.1 |
Times cited |
53 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; The work was supported by the Lloyd's Register Foundation, EPSRC-EP/N010345/1, the European Research Council, the Graphene Flagship, the Deutsche Forschungsgemeinschaft project TRR 234 “CataLight” (Project B7, Grant No. 364549901), and the research infrastructure Grant No. INST 275/25 7-1 FUGG. E.G. and L.M. acknowledge the EPSRC NowNANO programme for funding. ; |
Approved |
Most recent IF: 17.1; 2020 IF: 13.942 |
Call Number |
UA @ admin @ c:irua:170708 |
Serial |
6586 |
Permanent link to this record |
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Author |
Mogg, L.; Hao, G.-P.; Zhang, S.; Bacaksiz, C.; Zou, Y.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. |
Title |
Atomically thin micas as proton-conducting membranes |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
Volume |
14 |
Issue |
10 |
Pages |
962-+ |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Monolayers of graphene and hexagonal boron nitride (hBN) are highly permeable to thermal protons1,2. For thicker two-dimensional (2D) materials, proton conductivity diminishes exponentially, so that, for example, monolayer MoS2 that is just three atoms thick is completely impermeable to protons1. This seemed to suggest that only one-atom-thick crystals could be used as proton-conducting membranes. Here, we show that few-layer micas that are rather thick on the atomic scale become excellent proton conductors if native cations are ion-exchanged for protons. Their areal conductivity exceeds that of graphene and hBN by one to two orders of magnitude. Importantly, ion-exchanged 2D micas exhibit this high conductivity inside the infamous gap for proton-conducting materials3, which extends from ∼100 °C to 500 °C. Areal conductivity of proton-exchanged monolayer micas can reach above 100 S cm−2 at 500 °C, well above the current requirements for the industry roadmap4. We attribute the fast proton permeation to ~5-Å-wide tubular channels that perforate micas’ crystal structure, which, after ion exchange, contain only hydroxyl groups inside. Our work indicates that there could be other 2D crystals5 with similar nanometre-scale channels, which could help close the materials gap in proton-conducting applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000488977100016 |
Publication Date |
2019-09-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-3387; 1748-3395 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
38.986 |
Times cited |
44 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; The work was supported by the Lloyd's Register Foundation, the Engineering and Physical Sciences Research Council (EPSRC)-EP/N010345/1, EP/M010619/1 and EP/ P009050/1, the European Research Council, the Graphene Flagship and the Royal Society. M.L.-H. acknowledges a Leverhulme Early Career Fellowship, G.-P.H. acknowledges a Marie Curie International Incoming Fellowship, and L.M. acknowledges the EPSRC NOWNano programme for funding. Y.Z. acknowledges the assistance of Eric Prestat in TEM specimen preparation. Computational resources were provided by the TUBITAK ULAKBIM High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; |
Approved |
Most recent IF: 38.986 |
Call Number |
UA @ admin @ c:irua:163589 |
Serial |
5407 |
Permanent link to this record |
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Author |
Batuk, D.; Batuk, M.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Tyablikov, O.A.; Hadermann, J.; Abakumov, A.M. |
Title |
Crystal Structure, Defects, Magnetic and Dielectric Properties of the Layered Bi3n+1Ti7Fe3n-3,O9n+11 Perovskite-Anatase lntergrowths |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
56 |
Issue |
56 |
Pages |
931-942 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The Bi3n+1Ti7Fe3n-3,O9n+11 materials are built of (001)(p) plane parallel perovskite blocks with a thickness of n (Ti,Fe)O-6 octahedra, separated by periodic translational interfaces. The interfaces are based on anatase-like chains of edge -sharing (Ti,Fe)O-6 octahedra. Together with the octahedra of the perovskite blocks, they create S-shaped tunnels stabilized by lone pair Bi3+ cations. In this work, the structure of the n = 4-6 Bi3n+1Ti7Fe3n-3,O9n+11 homologues is analyzed in detail using advanced transmission electron microscopy, powder X-ray diffraction, and Mossbauer spectroscopy. The connectivity of the anatase-like chains to the perovskite blocks results in,a 3ap periodicity along the interfaces, so that they can be located either on top of each other or with shifts of +/- a(p) along [100](p). The ordered arrangement of the interfaces gives rise to orthorhombic Immm and monoclinic A2/m polymorphs with the unit cell parameters a = 3a(p), b = b(p), c = 2(n + 1)c(p) and a = 3a(p), b = b(p), c = 2(n + 1)c(p) – a(p), respectively. While the n = 3 compound is orthorhombic, the monoclinic modification is more favorable in higher homologues. The Bi3n+1Ti7Fe3n-3,O9n+11 structures demonstrate intricate patterns of atomic displacements in the perovskite blocks, which are supported by the stereochemical activity of the Bi3+ cations. These patterns are coupled to the cationic coordination of the oxygen atoms in the (Ti,Fe)O-2 layers at the border of the perovskite blocks. The coupling is strong in the 1/ = 3, 4 homologues, but gradually reduces with the increasing thickness of the perovskite blocks, so that, in the n = 6 compound, the dominant mode of atomic displacements is aligned along the interface planes. The displacements in the adjacent perovskite blocks tend to order antiparallel, resulting in an overall antipolar structure. The Bi3n+1Ti7Fe3n-3,O9n+11 materials demonstrate an unusual diversity of structure defects. The n = 4-6 homologues are robust antiferromagnets below T-N = 135, 220, and 295 K, respectively. They show a high dielectric constant that weakly increases with temperature and is relatively insensitive to the Ti/Fe ratio. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000392262400029 |
Publication Date |
2016-12-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0020-1669 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
3 |
Open Access |
Not_Open_Access |
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; The work was supported by the Russian Science Foundation (grant 14-13-00680). ; |
Approved |
Most recent IF: 4.857 |
Call Number |
UA @ lucian @ c:irua:141471 |
Serial |
4495 |
Permanent link to this record |
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Author |
Horzum, S.; Torun, E.; Serin, T.; Peeters, F.M. |
Title |
Structural, electronic and optical properties of Cu-doped ZnO : experimental and theoretical investigation |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Philosophical magazine |
Abbreviated Journal |
Philos Mag |
Volume |
96 |
Issue |
96 |
Pages |
1743-1756 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Experiments are supplemented with ab initio density functional theory (DFT) calculations in order to investigate how the structural, electronic and optical properties of zinc oxide (ZnO) thin films are modified upon Cu doping. Changes in characteristic properties of doped thin films, that are deposited on a glass substrate by sol-gel dip coating technique, are monitored using X-ray diffraction (XRD) and UV measurements. Our ab initio calculations show that the electronic structure of ZnO can be well described by DFT+U/G(0)W(0) method and we find that Cu atom substitutional doping in ZnO is the most favourable case. Our XRD measurements reveal that the crystallite size of the films decrease with increasing Cu doping. Moreover, we determine the optical constants such as refractive index, extinction coefficient, optical dielectric function and optical energy band gap values of the films by means of UV-Vis transmittance spectra. The optical band gap of ZnO the thin film linearly decreases from 3.25 to 3.20 eV at 5% doping. In addition, our calculations reveal that the electronic defect states that stem from Cu atoms are not optically active and the optical band gap is determined by the ZnO band edges. Experimentally observed structural and optical results are in good agreement with our theoretical results. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000376076500002 |
Publication Date |
2016-05-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1478-6435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.505 |
Times cited |
29 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; Theoretical part of this work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. Experimental part of this work was supported by Ankara University BAP under Project Number [14B0443001]. ; |
Approved |
Most recent IF: 1.505 |
Call Number |
UA @ lucian @ c:irua:134161 |
Serial |
4254 |
Permanent link to this record |
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Author |
Salvant, J.; Williams, J.; Ganio, M.; Casadio, F.; Daher, C.; Sutherland, K.; Monico, L.; Vanmeert, F.; De Meyer, S.; Janssens, K.; Cartwright, C.; Walton, M. |
Title |
A Roman Egyptian Painting Workshop : technical investigation of the portraits from Tebtunis, Egypt |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Archaeometry |
Abbreviated Journal |
Archaeometry |
Volume |
60 |
Issue |
4 |
Pages |
815-833 |
Keywords |
A1 Journal article; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Roman-period mummy portraits are considered to be ancient antecedents of modern portraiture. However, the techniques and materials used in their manufacture are not thoroughly understood. Analytical study of the pigments as well as the binding materials helps to address questions on what aspects of the painting practices originate from Pharaonic and/or Graeco-Roman traditions, and can aid in determining the provenance of the raw materials from potential locations across the ancient Mediterranean and European worlds. Here, one of the largest assemblages of mummy portraits to remain intact since their excavation from the site of Tebtunis in Egypt was examined using multiple analytical techniques to address how they were made. The archaeological evidence suggests that these portraits were products of a single workshop and, correspondingly, they are found to be made using similar techniques and materials: wax-based and lead white-rich paint combined with a variety of iron-based pigments (including hematite, goethite and jarosite), as well as Egyptian blue, minium, indigo and madder lake to create subtle variations and tones. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000438195100011 |
Publication Date |
2017-11-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-813x; 1475-4754 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.47 |
Times cited |
6 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This collaborative initiative is part of NU-ACCESS's broad portfolio of activities, made possible by generous support of the Andrew W. Mellon Foundation as well as supplemental support provided by the Materials Research Center, the Office of the Vice President for Research, the McCormick School of Engineering and Applied Science and the Department of Materials Science and Engineering at Northwestern University. This work made use of the Keck-II facility of the NUANCE Center at Northwestern University, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF NNCI-1542205); the MRSEC program (NSF DMR-1121262) at the Materials Research Center; the International Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois, through the IIN. Part of this research was carried out at the light source PETRA III at DESY, a member of the Helmholtz Association (HGF), and at ESRF (experiment no. HG-79). We are grateful to Marine Cotte and Wout De Nolf for their support during the experiment at beamline ID21. We would like to thank Gerald Falkenberg and Jan Garrevoet for their assistance in using beamline P06. ; |
Approved |
Most recent IF: 1.47 |
Call Number |
UA @ admin @ c:irua:152396 |
Serial |
5455 |
Permanent link to this record |
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Author |
Vargas Paredes, A.A.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Perali, A. |
Title |
Crossband versus intraband pairing in superconductors: signatures and consequences of the interplay |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
101 |
Issue |
9 |
Pages |
094516-94517 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We analyze the paradigmatic competition between intraband and crossband Cooper-pair formation in twoband superconductors, neglected in most works to date. We derive the phase-sensitive gap equations and describe the crossover between the intraband-dominated and the crossband-dominated regimes, delimited by a “gapless” state. Experimental signatures of crosspairing comprise notable gap splitting in the excitation spectrum, non-BCS behavior of gaps versus temperature, as well as changes in the pairing symmetry as a function of temperature. The consequences of these findings are illustrated on the examples of MgB2 and Ba0.6K0.4Fe2As2. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000522074900002 |
Publication Date |
2020-03-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.7 |
Times cited |
14 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This collaborative work was fostered within the international Multi Super network on Multi-condensate Superconductivity and Superfluidity [70]. The authors thank Andrea Guidini for his help during the initial stage of this work and Laura Fanfarillo for useful discussions. This work was partially supported by the Italian MIUR through the PRIN 2015 program (Contract No. 2015C5SEJJ001) and the Research Foundation -Flanders (FWO). A.A.V.-P. acknowledges support by the joint doctoral program and by the Erasmus+ exchange between the University of Antwerp and the University of Camerino. M.V.M. gratefully acknowledges support from a Visiting Professorship at the University of Camerino. A.S. and A.V. acknowledge support from the CAPES/Print Grant, Process No. 88887.333666/ 2019-00 (Brazil) and the Russian Science Foundation Project No. 18-12-00429, respectively. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
Call Number |
UA @ admin @ c:irua:168605 |
Serial |
6479 |
Permanent link to this record |
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Author |
Terzano, R.; Denecke, M.A.; Falkenberg, G.; Miller, B.; Paterson, D.; Janssens, K. |
Title |
Recent advances in analysis of trace elements in environmental samples by X-ray based techniques (IUPAC Technical Report) |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Pure and applied chemistry |
Abbreviated Journal |
Pure Appl Chem |
Volume |
91 |
Issue |
6 |
Pages |
1029-1063 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Trace elements analysis is a fundamental challenge in environmental sciences. Scientists measure trace elements in environmental media in order to assess the quality and safety of ecosystems and to quantify the burden of anthropogenic pollution. Among the available analytical techniques, X-ray based methods are particularly powerful, as they can quantify trace elements in situ. Chemical extraction is not required, as is the case for many other analytical techniques. In the last few years, the potential for X-ray techniques to be applied in the environmental sciences has dramatically increased due to developments in laboratory instruments and synchrotron radiation facilities with improved sensitivity and spatial resolution. In this report, we summarize the principles of the X-ray based analytical techniques most frequently employed to study trace elements in environmental samples. We report on the most recent developments in laboratory and synchrotron techniques, as well as advances in instrumentation, with a special attention on X-ray sources, detectors, and optics. Lastly, we inform readers on recent applications of X-ray based analysis to different environmental matrices, such as soil, sediments, waters, wastes, living organisms, geological samples, and atmospheric particulate, and we report examples of sample preparation. |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000471262400011 |
Publication Date |
2019-05-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0033-4545 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.626 |
Times cited |
3 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This document was developed as a part of IUPAC, Funder Id: http://dx.doi.org/ 10.13039/100006987, Project #2016-019-2-600 “Trace elements analysis of environmental samples with X-rays: from synchrotron to lab and from lab to synchrotron” led by Roberto Terzano (Task Group Chair). Task Group Members for this project were: Melissa Anne Denecke, Gerald Falkenberg, Armin Gross, Koen Janssens, Bradley Miller, David Paterson, Ryan Tappero, Fang-Jie Zhao. Their contribution to the project is gratefully acknowledged. ; |
Approved |
Most recent IF: 2.626 |
Call Number |
UA @ admin @ c:irua:161369 |
Serial |
5803 |
Permanent link to this record |
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Author |
Tiwari, S.; Van de Put, M.L.; Sorée, B.; Vandenberghe, W.G. |
Title |
Carrier transport in two-dimensional topological insulator nanoribbons in the presence of vacancy defects |
Type |
A1 Journal article |
Year |
2019 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
6 |
Issue |
2 |
Pages |
025011 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using the non-equilibrium Green's function formalism, we study carrier transport through imperfect two-dimensional (2D) topological insulator (TI) ribbons. In particular, we investigate the effect of vacancy defects on the carrier transport in 2D TI ribbons with hexagonal lattice structure. To account for the random distribution of the vacancy defects, we present a statistical study of varying defect densities by stochastically sampling different defect configurations. We demonstrate that the topological edge states of TI ribbons are fairly robust against a high concentration (up to 2%) of defects. At very high defect densities, we observe an increased inter-edge interaction, mediated by the localisation of the edge states within the bulk region. This effect causes significant back-scattering of the, otherwise protected, edge-states at very high defect concentrations (>2%), resulting in a loss of conduction through the TI ribbon. We discuss how this coherent vacancy scattering can be used to our advantage for the development of TI-based transistors. We find that there is an optimal concentration of vacancies yielding an ON-OFF current ratio of up to two orders of magnitude. Finally, we investigate the importance of spin-orbit coupling on the robustness of the edge states in the TI ribbon and show that increased spin-orbit coupling could further increase the ON-OFF ratio. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000457856400002 |
Publication Date |
2019-01-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
3 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This material is based in part upon work supported by the National Science Foundation under Grant Number 1710066. The project or effort depicted was or is sponsored by the Department of Defense, Defense Threat Reduction Agency. The content of the information does not necessarily reflect the position or the policy of the federal government, and no official endorsement should be inferred. This work was supported by imec's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ admin @ c:irua:157464 |
Serial |
5198 |
Permanent link to this record |
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|
|
Author |
Vermang, B.; Brammertz, G.; Meuris, M.; Schnabel, T.; Ahlswede, E.; Choubrac, L.; Harel, S.; Cardinaud, C.; Arzel, L.; Barreau, N.; van Deelen, J.; Bolt, P.-J.; Bras, P.; Ren, Y.; Jaremalm, E.; Khelifi, S.; Yang, S.; Lauwaert, J.; Batuk, M.; Hadermann, J.; Kozina, X.; Handick, E.; Hartmann, C.; Gerlach, D.; Matsuda, A.; Ueda, S.; Chikyow, T.; Felix, R.; Zhang, Y.; Wilks, R.G.; Baer, M. |
Title |
Wide band gap kesterite absorbers for thin film solar cells: potential and challenges for their deployment in tandem devices |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Sustainable Energy & Fuels |
Abbreviated Journal |
|
Volume |
3 |
Issue |
9 |
Pages |
2246-2259 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
This work reports on developments in the field of wide band gap Cu2ZnXY4 (with X = Sn, Si or Ge, and Y = S, Se) kesterite thin film solar cells. An overview on recent developments and the current understanding of wide band gap kesterite absorber layers, alternative buffer layers, and suitable transparent back contacts is presented. Cu2ZnGe(S,Se)(4) absorbers with absorber band gaps up to 1.7 eV have been successfully developed and integrated into solar cells. Combining a CdS buffer layer prepared by an optimized chemical bath deposition process with a 1.36 eV band gap absorber resulted in a record Cu2ZnGeSe4 cell efficiency of 7.6%, while the highest open-circuit voltage of 730 mV could be obtained for a 1.54 eV band gap absorber and a Zn(O,S) buffer layer. Employing InZnOx or TiO2 protective top layers on SnO2:In transparent back contacts yields 85-90% of the solar cell performance of reference cells (with Mo back contact). These advances show the potential as well as the challenges of wide band gap kesterites for future applications in high-efficiency and low-cost tandem photovoltaic devices. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000482057500004 |
Publication Date |
2019-06-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
2 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project has received funding from the European Union's Horizon 2020 Research and Innovation Program under grant agreement No. 640868. The synchrotron radiation experiments were performed at the SPring-8 beamline BL15XU with the approval of the NIMS Synchrotron X-ray Station (Proposals 2016A4600, 2016B4601, and 2017A4600) and at BESSY II with the approval of HZB. B. Vermang has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (grant agreement no. 715027). ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:161785 |
Serial |
5404 |
Permanent link to this record |
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|
|
Author |
Florea, A.; De Jong, M.; De Wael, K. |
Title |
Electrochemical strategies for the detection of forensic drugs |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Current opinion in electrochemistry |
Abbreviated Journal |
|
Volume |
11 |
Issue |
11 |
Pages |
34-40 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Illicit drugs consumption and trafficking is spread worldwide and remains an increasing challenge for local authorities. Forensic drugs and their metabolites are released into wastewaters due to human excretion after illegal consumption of drugs and occasionally due to disposal of clandestine laboratory wastes into sewage systems, being recently classified as the latest group of emerging pollutants. Hence, it is essential to have efficient and accurate methods to detect these type of compounds in seized street samples, biological fluids and wastewaters in order to reduce and prevent trafficking and consumption and negative effects on aquatic systems. Electrochemical strategies offer a fast, portable, low-cost and accurate alternative to chromatographic and spectrometric methods, for the analysis of forensic drugs and metabolites in different matrices. Recent electrochemical strategies applied to the detection of illicit drugs in wastewaters, biological fluids and street samples are presented in this review, together with the impact of drug consumption on the environment. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000453710900007 |
Publication Date |
2018-07-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2451-9103; 2451-9111 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
7 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. The authors also acknowledge financial support from BELSPO, IOF-SBO and UAntwerp. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:152366 |
Serial |
5597 |
Permanent link to this record |
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|
|
Author |
Florea, A.; Schram, J.; De Jong, M.; Eliaerts, J.; Van Durme, F.; Kaur, B.; Samyn, N.; De Wael, K. |
Title |
Electrochemical strategies for adulterated heroin samples |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
91 |
Issue |
12 |
Pages |
7920-7928 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Electrochemical strategies to selectively detect heroin in street samples without the use of complicated electrode modifications were developed for the first time. For this purpose, heroin, mixing agents (adulterants, cutting agent, and impurities), and their binary mixtures were subjected to square wave voltammetry measurements at bare graphite electrodes at pH 7.0 and pH 12.0, in order to elucidate the unique electrochemical fingerprint of heroin and mixing agents as well as possible interferences or reciprocal influences. Adjusting the pH from pH 7.0 to pH 12.0 allowed a more accurate detection of heroin in the presence of most common mixing agents. Furthermore, the benefit of introducing a preconditioning step prior to running square wave voltammetry on the electrochemical fingerprint enrichment was explored. Mixtures of heroin with other drugs (cocaine, 3,4-methylenedioxymethamphetamine, and morphine) were also tested to explore the possibility of their discrimination and simultaneous detection. The feasibility of the proposed electrochemical strategies was tested on realistic heroin street samples from forensic cases, showing promising results for fast, on-site detection tools of drugs of abuse. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
|
Language |
|
Wos |
000472682000056 |
Publication Date |
2019-05-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
2 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. The authors also acknowledge IOF (UAntwerp) and Belspo for financial support. ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:160061 |
Serial |
5596 |
Permanent link to this record |
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|
|
Author |
De Jong, M.; Florea, A.; de Vries, A.-M.; van Nuijs, A.L.N.; Covaci, A.; Van Durme, F.; Martins, J.C.; Samyn, N.; De Wael, K. |
Title |
Levamisole : a common adulterant in cocaine street samples hindering electrochemical detection of cocaine |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
90 |
Issue |
8 |
Pages |
5290-5297 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
Abstract |
The present work investigates the electrochemical determination of cocaine in the presence of levamisole, one of the most common adulterants found in cocaine street samples. Levamisole misleads cocaine color tests, giving a blue color (positive test) even in the absence of cocaine. Moreover, the electrochemical detection of cocaine is also affected by the presence of levamisole, with a suppression of the oxidation signal of cocaine. When levamisole is present in the sample in ratios higher than 1:1, the cocaine signal is no longer detected, thus leading to false negative results. Mass spectrometry and nuclear magnetic resonance were used to investigate if the signal suppression is due to the formation of a complex between cocaine and levamisole in bulk solution. Strategies to eliminate this suppressing effect are further suggested in this manuscript. In a first approach, the increase of the pH of the sample solution from pH 7 to pH 12 allowed the voltammetric determination of cocaine in the presence of levamisole in a concentration range from 10 to 5000 μM at nonmodified graphite disposable electrodes with a detection limit of 5 μM. In a second approach, the graphite electrode was cathodically pretreated, resulting in the presence of oxidation peaks of both cocaine and levamisole, with a detection limit for cocaine of 3 μM over the linear range of concentrations from 10 to 2500 μM. Both these strategies have been successfully applied for the simultaneous detection of cocaine and levamisole in three street samples on unmodified graphite disposable electrodes. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000430512200049 |
Publication Date |
2018-02-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
8 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by BR/314/PI/ APTADRU Project and IOF-SBO (UAntwerp). Alexander van Nuijs acknowledges the Research Foundation-Flanders (FWO) for his postdoctoral fellowship. ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:149528 |
Serial |
5693 |
Permanent link to this record |
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|
Author |
De Jong, M.; Florea, A.; Eliaerts, J.; Van Durme, F.; Samyn, N.; De Wael, K. |
Title |
Tackling poor specificity of cocaine color tests by electrochemical strategies |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
90 |
Issue |
11 |
Pages |
6811-6819 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
This paper presents electrochemical strategies for the fast screening of cocaine and most common cutting agents found in seized drug samples. First, a study on the performance of Scott color tests on cocaine and a wide range of cutting agents is described. The cutting agents causing false positive or false negative results when in mixture with cocaine are identified. To overcome the lack of specificity of color tests, we further propose a fast screening strategy by means of square wave voltammetry on disposable graphite screen printed electrodes, which reveals the unique fingerprint of cocaine and cutting agents. By employing a forward and backward scan and by a dual pH strategy, we enrich the electrochemical fingerprint and enable the simultaneous detection of cocaine and cutting agents. The effectiveness of the developed strategies was tested for the detection of cocaine in seized cocaine samples and compared with the color tests. Moreover, we prove the usefulness of square wave voltammetry for predicting possible interfering agents in color tests, based on the reduction peak of cobalt thiocyanate. The developed electrochemical strategies allow for a quick screening of seized cocaine samples resulting in a selective identification of drugs and cutting agents. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000434893200066 |
Publication Date |
2018-05-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
7 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by Grants BR/314 /PI/APTADRU and IOF-SBO. ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:151316 |
Serial |
5867 |
Permanent link to this record |
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Author |
Moro, G.; Bottari, F.; Sleegers, N.; Florea, A.; Cowen, T.; Moretto, L.M.; Piletsky, S.; De Wael, K. |
Title |
Conductive imprinted polymers for the direct electrochemical detection of beta-lactam antibiotics: The case of cefquinome |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
Sensor Actuat B-Chem |
Volume |
297 |
Issue |
297 |
Pages |
126786 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A biomimetic sensor for cefquinome (CFQ) was designed at multi-walled carbon nanotubes modified graphite screen-printed electrodes (MWCNTs-G-SPEs) as a proof-of-concept for the creation of a sensors array for beta-lactam antibiotics detection in milk. The sensitive and selective detection of antibiotic residues in food and environment is a fundamental step in the elaboration of prevention strategies to fight the insurgence of antimicrobial resistance (AMR) as recommended by authorities around the world (EU, WHO, FDA). The detection strategy is based on the characteristic electrochemical fingerprint of the target antibiotic cefquinome. A conducive electropolymerized molecularly imprinted polymer (MIP) coupled with MWCNTs was found to be the optimal electrode modifier, able to provide an increased selectivity and sensitivity for CFQ detection. The design of CFQ-MIP was facilitated by the rational selection of the monomer, 4-aminobenzoic acid (4-ABA). The electropolymerization process of 4-ABA have not been fully elucidated yet; for this reason a thorough study and optimization of electropolymerization conditions was performed to obtain a conducive and stable poly(4-ABA) film. The modified electrodes were characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and cyclic voltammetry (CV). CFQ-MIP were synthesized at MWCNT-G-SPEs by electropolyrnerization in pH approximate to 1 (0.1 M sulphuric acid) with a monomer:template ratio of 5:1. Two different analytical protocols were tested (single and double step detection) to minimize unspecific adsorptions and improve the sensitivity. Under optimal conditions, the lowest CFQ concentration detectable by square wave voltammetry (SWV) at the modified sensor was 50 nM in 0.1 M phosphate buffer pH 2. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000478562700020 |
Publication Date |
2019-07-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0925-4005 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.401 |
Times cited |
4 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223. This work was also supported by FWO. ; |
Approved |
Most recent IF: 5.401 |
Call Number |
UA @ admin @ c:irua:161777 |
Serial |
5549 |
Permanent link to this record |
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Author |
Rezvani, S.J.; Perali, A.; Fretto, M.; De Leo, N.; Flammia, L.; Milošević, M.; Nannarone, S.; Pinto, N. |
Title |
Substrate-induced proximity effect in superconducting niobium nanofilms |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Condensed Matter |
Abbreviated Journal |
|
Volume |
4 |
Issue |
1 |
Pages |
4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Structural and superconducting properties of high-quality niobium nanofilms with different thicknesses are investigated on silicon oxide (SiO2) and sapphire substrates. The role played by the different substrates and the superconducting properties of the Nb films are discussed based on the defectivity of the films and on the presence of an interfacial oxide layer between the Nb film and the substrate. The X-ray absorption spectroscopy is employed to uncover the structure of the interfacial layer. We show that this interfacial layer leads to a strong proximity effect, especially in films deposited on a SiO2 substrate, altering the superconducting properties of the Nb films. Our results establish that the critical temperature is determined by an interplay between quantum-size effects, due to the reduction of the Nb film thicknesses, and proximity effects. The detailed investigation here provides reference characterizations and has direct and important implications for the fabrication of superconducting devices based on Nb nanofilms. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000464289300001 |
Publication Date |
2018-12-31 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
2410-3896 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
3 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project was financially supported by University of Camerino, FAR project CESEMN. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:159463 |
Serial |
5233 |
Permanent link to this record |
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Author |
Morales-Yánez, F.; Trashin, S.; Sariego, I.; Roucher, C.; Paredis, L.; Chico, M.; De Wael, K.; Muyldermans, S.; Cooper, P.; Polman, K. |
Title |
Electrochemical detection of Toxocara canis excretory-secretory antigens in children from rural communities in Esmeraldas Province, Ecuador : association between active infection and high eosinophilia |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Parasites & Vectors |
Abbreviated Journal |
Parasite Vector |
Volume |
13 |
Issue |
1 |
Pages |
245-247 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Background The diagnosis of active Toxocara canis infections in humans is challenging. Larval stages of T. canis do not replicate in human tissues and disease may result from infection with a single T. canis larva. Recently, we developed a nanobody-based electrochemical magnetosensor assay with superior sensitivity to detect T. canis excretory-secretory (TES) antigens. Here, we evaluate the performance of the assay in children from an Ecuadorian birth cohort that followed children to five years of age. Methods Samples were selected based on the presence of peripheral blood eosinophilia and relative eosinophil counts. The samples were analyzed by the nanobody-based electrochemical magnetosensor assay, which utilizes a bivalent biotinylated nanobody as capturing agent on the surface of streptavidin pre-coated paramagnetic beads. Detection was performed by a different nanobody chemically labelled with horseradish peroxidase. Results Of 87 samples tested, 33 (38%) scored positive for TES antigen recognition by the electrochemical magnetosensor assay. The average concentration of TES antigen in serum was 2.1 ng/ml (SD = 1.1). The positive result in the electrochemical assay was associated with eosinophilia > 19% (P = 0.001). Parasitological data were available for 57 samples. There was no significant association between positivity by the electrochemical assay and the presence of other soil-transmitted helminth infections. Conclusions Our nanobody-based electrochemical assay provides highly sensitive quantification of TES antigens in serum and has potential as a valuable tool for the diagnosis of active human toxocariasis. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000535618800003 |
Publication Date |
2020-05-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1756-3305 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.2 |
Times cited |
|
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project was funded by the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO-Flanders), project No. G.0189.13N. The ECUAVIDA cohort was funded by the Wellcome Trust (grant 072405/Z/03/Z and 088862/Z/09/Z). ; |
Approved |
Most recent IF: 3.2; 2020 IF: 3.08 |
Call Number |
UA @ admin @ c:irua:168966 |
Serial |
6501 |
Permanent link to this record |
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Author |
Morales-Yanez, F.; Trashin, S.; Hermy, M.; Sariego, I.; Polman, K.; Muyldermans, S.; De Wael, K. |
Title |
Fast one-step ultrasensitive detection of toxocara canis antigens by a nanobody-based electrochemical magnetosensor |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
91 |
Issue |
18 |
Pages |
11582-11588 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Human toxocariasis (HT) is a cosmopolitan zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis. Current HT diagnostic methods do not discriminate between active and past infections. Here, we present a method to quantify Toxocara excretory/secretory antigen, aiming to identify active cases of HT. High specificity is achieved by employing nanobodies (Nbs), single domain antigen binding fragments from camelid heavy chain-only antibodies. High sensitivity is obtained by the design of an electrochemical magnetosensor with an amperometric read-out. Reliable detection of TES antigen at 10 and 30 pg/mL level was demonstrated in phosphate buffered saline and serum, respectively. Moreover, the assay showed no cross-reactivity with other nematode antigens. To our knowledge, this is the most sensitive method to quantify the TES antigen so far. It also has great potential to develop point of care diagnostic systems in other conditions where high sensitivity and specificity are required. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000487156900016 |
Publication Date |
2019-08-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
2 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project was funded by the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO-Flanders, Project G.0189.13N) and BOF UAntwerp. The authors acknowledge Prof. Pierre Dorny (Institute of Tropical Medicine Antwerp) and Dr. Beatrice Nickel (Swiss Institute of Tropical Medicine) for providing the antigens needed for the cross-reactivity experiments. ; |
Approved |
Most recent IF: 6.32 |
Call Number |
UA @ admin @ c:irua:163784 |
Serial |
5621 |
Permanent link to this record |
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|
|
Author |
Thirumalraj, alamurugan; Palanisamy, S.; Chen, S.-M.; De Wael, K. |
Title |
A graphene/gelatin composite material for the entrapment of hemoglobin for bioelectrochemical sensing applications |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal of the electrochemical society |
Abbreviated Journal |
J Electrochem Soc |
Volume |
163 |
Issue |
7 |
Pages |
265-271 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In the present work, a novel graphene (GN) and gelatin (GTN) composite was prepared and used as an immobilization matrix for hemoglobin (Hb). Compared with Hb immobilized on a bare, GN or GTN modified glassy carbon electrode (GCE), a stable and pair of well-defined quasi redox couple was observed at an Hb modified GN/GTN composite GCE at a formal potential of −0.306 V versus Ag|AgCl. The direct electrochemical behavior of Hb was greatly enhanced by the presence of both GTN and GN. A heterogeneous electron transfer rate constant (Ks) was calculated as 3.82 s−1 for Hb immobilized at GN/GTN modified GCE, which indicates the fast direct electron transfer of Hb toward the electrode surface. The biosensor shows a stable and wide linear response for H2O2 in the linear response range from 0.1 μM to 786.6 μM with an analytical sensitivity and limit of detection of 0.48 μAμM−1 cm−2 and 0.04 μM, respectively. The fabricated biosensor holds its high selectivity in the presence of potentially active interfering species and metal ions. The biosensor shows its satisfactory practical ability in the commercial contact lens solution and human serum samples. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000377412900047 |
Publication Date |
2016-04-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0013-4651 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.259 |
Times cited |
9 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This project was supported by the Ministry of Science and Technology (project no. NSC1012113M027001MY3), Taiwan (Republic of China). The authors express their sincere thanks to Prof. Bih-Show Lou, Chemistry Division, Center for General Education, Chang Gung University, Tao-Yuan, Taiwan for providing the human serum samples. ; |
Approved |
Most recent IF: 3.259 |
Call Number |
UA @ admin @ c:irua:132627 |
Serial |
5635 |
Permanent link to this record |
|
|
|
Author |
Quan, L.N.; Ma, D.; Zhao, Y.; Voznyy, O.; Yuan, H.; Bladt, E.; Pan, J.; de Arquer, F.P.G.; Sabatini, R.; Piontkowski, Z.; Emwas, A.-H.; Todorovic, P.; Quintero-Bermudez, R.; Walters, G.; Fan, J.Z.; Liu, M.; Tan, H.; Saidaminov, M., I; Gao, L.; Li, Y.; Anjum, D.H.; Wei, N.; Tang, J.; McCamant, D.W.; Roeffaers, M.B.J.; Bals, S.; Hofkens, J.; Bakr, O.M.; Lu, Z.-H.; Sargent, E.H. |
Title |
Edge stabilization in reduced-dimensional perovskites |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Nature Communications |
Abbreviated Journal |
Nat Commun |
Volume |
11 |
Issue |
1 |
Pages |
170 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Reduced-dimensional perovskites are attractive light-emitting materials due to their efficient luminescence, color purity, tunable bandgap, and structural diversity. A major limitation in perovskite light-emitting diodes is their limited operational stability. Here we demonstrate that rapid photodegradation arises from edge-initiated photooxidation, wherein oxidative attack is powered by photogenerated and electrically-injected carriers that diffuse to the nanoplatelet edges and produce superoxide. We report an edge-stabilization strategy wherein phosphine oxides passivate unsaturated lead sites during perovskite crystallization. With this approach, we synthesize reduced-dimensional perovskites that exhibit 97 +/- 3% photoluminescence quantum yields and stabilities that exceed 300 h upon continuous illumination in an air ambient. We achieve green-emitting devices with a peak external quantum efficiency (EQE) of 14% at 1000 cd m(-2); their maximum luminance is 4.5 x 10(4) cd m(-2) (corresponding to an EQE of 5%); and, at 4000 cd m(-2), they achieve an operational half-lifetime of 3.5 h. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000551458200001 |
Publication Date |
2020-01-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
16.6 |
Times cited |
147 |
Open Access |
OpenAccess |
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This publication is based in part on work supported by an award (KUS-11-009-21) from the King Abdullah University of Science and Technology (KAUST), by the Ontario Research Fund Research Excellence Program, by the Ontario Research Fund (ORF), by the Natural Sciences and Engineering Research Council (NSERC) of Canada, and by the US Department of Navy, Office of Naval Research (Grant Award No. N00014-17-12524). H.Y. acknowledges the Research Foundation-Flanders (FWO Vlaanderen) for a postdoctoral fellowship. E.B. gratefully acknowledges financial support by the Research Foundation-Flanders (FWO Vlaanderen). S.B. acknowledges financial support from European Research Council (ERC Starting Grant #815128-REALNANO). M.B.J.R. and J.H. acknowledge the Research Foundation-Flanders (FWO, Grants G.0962.13, G.0B39.15, AKUL/11/14 and G0H6316N), KU Leuven Research Fund (C14/15/053) and the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ ERC Grant Agreement No. [307523], ERC-Stg LIGHT to M.B.J.R. DFT calculations were performed on the IBM BlueGene Q supercomputer with support from the Southern Ontario Smart Computing Innovation Platform (SOSCIP). M.I.S. acknowledges the Banting Postdoctoral Fellowship program from the Natural Sciences and Engineering Research Council of Canada (NSERC). H.T. acknowledges the Netherlands Organisation for Scientific Research (NWO) for a Rubicon grant (680-50-1511). ; sygma |
Approved |
Most recent IF: 16.6; 2020 IF: 12.124 |
Call Number |
UA @ admin @ c:irua:171327 |
Serial |
6496 |
Permanent link to this record |
|
|
|
Author |
Van der Donck, M.; Zarenia, M.; Peeters, F.M. |
Title |
Strong valley Zeeman effect of dark excitons in monolayer transition metal dichalcogenides in a tilted magnetic field |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
97 |
Issue |
8 |
Pages |
081109 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The dependence of the excitonic photoluminescence (PL) spectrum of monolayer transition metal dichalcogenides (TMDs) on the tilt angle of an applied magnetic field is studied. Starting from a four-band Hamiltonian we construct a theory which quantitatively reproduces the available experimental PL spectra for perpendicular and in-plane magnetic fields. In the presence of a tilted magnetic field, we demonstrate that the dark exciton PL peaks brighten due to the in-plane component of the magnetic field and split for light with different circular polarizations as a consequence of the perpendicular component of the magnetic field. This splitting is more than twice as large as the splitting of the bright exciton peaks in tungsten-based TMDs. We propose an experimental setup that will allow for accessing the predicted splitting of the dark exciton peaks in the PL spectrum. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000425603600001 |
Publication Date |
2018-02-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This Rapid Communication was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:149913UA @ admin @ c:irua:149913 |
Serial |
4948 |
Permanent link to this record |
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|
Author |
Hernandez Parrodi, J.C.; Lucas, H.; Gigantino, M.; Sauve, G.; Esguerra, J.L.; Einhäupl, P.; Vollprecht, D.; Pomberger, R.; Friedrich, B.; Van Acker, K.; Krook, J.; Svensson, N.; Van Passel, S. |
Title |
Integration of resource recovery into current waste management through (enhanced) landfill mining |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Detritus |
Abbreviated Journal |
|
Volume |
Volume 08 - December 2019 |
Issue |
Volume 08 - December 2019 |
Pages |
1 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
Europe has somewhere between 150,000 and 500,000 landfill sites, with an estimated 90% of them being “non-sanitary” landfills, predating the EU Landfill Directive of 1999/31/EC. These older landfills tend to be filled with municipal solid waste and often lack any environmental protection technology. “ Doing nothing”, state-of-theart aftercare or remediating them depends largely on technical, societal and economic conditions which vary between countries. Beside “ doing nothing' and landfill aftercare, there are different scenarios in landfill mining, from re-landfilling the waste into ”sanitary landfills" to seizing the opportunity for a combined resource-recovery and remediation strategy. This review article addresses present and future issues and potential opportunities for landfill mining as an embedded strategy in current waste management systems through a multi-disciplinary approach. In particular, three general landfill mining strategies are addressed with varying extents of resource recovery. These are discussed in relation to the main targets of landfill mining: (i) reduction of the landfill volume (technical), (ii) reduction of risks and impacts (environmental) and (iii) increase in resource recovery and overall profitability (economic). Geophysical methods could be used to determine the characteristics of the landfilled waste and subsurface structures without the need of an invasive exploration, which could greatly reduce exploration costs and time, as well as be useful to develop a procedure to either discard or select the most appropriate sites for (E)LFM. Material and energy recovery from land-filled waste can be achieved through mechanical processing coupled with thermochemical valorization technologies and residues upcycling techniques. Gasification could enable the upcycling of residues after thermal treatment into a new range of eco-friendly construction materials based on inorganic polymers and glass-ceramics. The multi-criteria assessment is directly influenced by waste- and technology related factors, which together with site-specific conditions, market and regulatory aspects, influence the environmental, economic and societal impacts of (E)LFM projects. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000504065300012 |
Publication Date |
2019-12-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This research has been funded by the European Union ' s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 721185 “NEW-MINE” (EU Training Network for Resource Recovery through Enhanced Landfill Mining; www.new-mine.eu). ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:165759 |
Serial |
6219 |
Permanent link to this record |
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|
|
Author |
Nguyen, H.T.T.; Obeid, M.M.; Bafekry, A.; Idrees, M.; Vu, T.V.; Phuc, H., V; Hieu, N.N.; Le Hoa, T.; Amin, B.; Nguyen, C., V |
Title |
Interfacial characteristics, Schottky contact, and optical performance of a graphene/Ga2SSe van der Waals heterostructure: Strain engineering and electric field tunability |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
102 |
Issue |
7 |
Pages |
075414-10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Two-dimensional graphene-based van der Waals heterostructures have received considerable interest because of their intriguing characteristics compared with the constituent single-layer two-dimensional materials. Here, we investigate the interfacial characteristics, Schottky contact, and optical performance of graphene/Ga2SSe van der Waals (vdW) heterostructure using first-principles calculations. The effects of stacking patterns, electric gating, and interlayer coupling on the interfacial properties of graphene/Ga2SSe heterostructures are also examined. Our results demonstrate that the Dirac cone of graphene is well preserved at the F point in all stacking patterns due to the weak vdW interactions, which keep the heterostructures feasible such that they can be obtained in further experiments. Moreover, depending on the stacking patterns, a small band gap of about 13-17 meV opens in graphene and has a high carrier mobility, indicating that the graphene/Ga2SSe heterostructures are potential candidates for future high-speed nanoelectronic applications. In the ground state, the graphene/Ga2SSe heterostructures form an n-type Schottky contact. The transformation from an n-type to a p-type Schottky contact or to an Ohmic contact can be forced by electric gating or by varying the interlayer coupling. Our findings could provide physical guidance for designing controllable Schottky nanodevices with high electronic and optical performances. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000557294500006 |
Publication Date |
2020-08-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.7 |
Times cited |
12 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under Grant No. 103.01-2019.05. The authors declare that there are no conflicts of interest regarding the publication of this paper. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
Call Number |
UA @ admin @ c:irua:171163 |
Serial |
6549 |
Permanent link to this record |
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|
Author |
Vermeulen, M.; Nuyts, G.; Sanyova, J.; Vila, A.; Buti, D.; Suuronen, J.-P.; Janssens, K. |
Title |
Visualization of As(III) and As(V) distributions in degraded paint micro-samples from Baroque- and Rococo-era paintings |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
Volume |
31 |
Issue |
9 |
Pages |
1913-1921 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Orpiment and realgar, both arsenic sulfide pigments respectively used for their vivid yellow and red-orange hues, are two of many artists' pigments that appear not to be stable upon light exposure, quickly degrading to arsenic trioxide and arsenate. This often results in whitening or transparency in the painted surfaces. While conventional techniques such as microscopic Raman (mu-RS) and microscopic Fourier transform infrared (mu-FTIR) spectroscopies can allow a quick and relatively easy identification of the orpiment, realgar, artificial arsenic sulfide glass and, to some extent, arsenic oxide, the identification and visualization of distributions of the degradation products – and especially arsenate compounds – in the paint micro-samples is generally more challenging. This challenge is due to the rather unfavorable limit of detection and low spectral resolution of such conventional spectroscopic techniques. This restricts the conclusions that can be drawn regarding the conservation state of valuable works of art. In this paper, we present how synchrotron radiation (SR) based techniques can overcome this challenge while working on painting cross-sections taken from a 17th-century painting by the Flemish artist Daniel Seghers (oil on canvas, Statens Museum for Kunst, Denmark) and an 18th-century French Chinoiserie (private collection, France). SR micro-X-ray fluorescence (m-XRF) mapping analysis performed on a visually degraded orpiment-containing paint stratigraphy reveals that arsenic is distributed throughout the entire cross-section, while X-ray absorption near edge structure (mu-XANES) demonstrated that the arsenic is present in both arsenite (As-III) and arsenate (As-V) forms. The latter compound(s), despite being barely identifiable by means of FTIR, were not only located at the surface of large and partially altered grains of arsenic sulfide but also spread throughout the entire paint stratigraphy. Their presence and distribution are attributed either to the complete degradation of smaller arsenic sulfide grains or to migration of the arsenates within the paint layer away from their original location of formation. The combination of mu-XRF and mu-XANES was very useful for the characterization of the advanced degradation state of the arsenic-containing pigments in paint systems; this type of information could not be obtained by means of conventional spectroscopic methods of microanalysis. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
|
Language |
|
Wos |
000382071200017 |
Publication Date |
2016-08-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.379 |
Times cited |
20 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This research is made possible with the support of the Belgian Science Policy Office (BELSPO) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (SD/RI/04A). The CATS gratefully acknowledge VILLUM FONDEN and VELUX FONDEN for infra-structural financial support as well as Anne Haack Christensen, Hannah Tempest and Johanne M. Nielsen for their help and suggestions. The European Synchrotron Radiation Facility is acknowledged for provision of synchrotron radiation facilities. ; |
Approved |
Most recent IF: 3.379 |
Call Number |
UA @ admin @ c:irua:135691 |
Serial |
5907 |
Permanent link to this record |
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|
|
Author |
Vermeulen, M.; Janssens, K.; Sanyova, J.; Rahemi, V.; McGlinchey, C.; De Wael, K. |
Title |
Assessing the stability of arsenic sulfide pigments and influence of the binding media on their degradation by means of spectroscopic and electrochemical techniques |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
Volume |
138 |
Issue |
138 |
Pages |
82-91 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In this paper, we used the semiconducting and lightfastness properties of synthetic and mineral arsenic sulfide pigments to study their stability by means of electrochemical and microfadometric techniques. A combination of these techniques shows that in the early stage of the degradation process, amorphous arsenic sulfides are more stable than both crystalline forms, while upon longer exposure time, amorphous pigments will fade more than both mineral pigments, making it less suitable. While the stability study was carried out on unbound pigments, the influence of the organic binder on the relative degradation of the arsenic sulfide pigments was investigated through a multi-analytical approach on pigment/binder mock-up paint samples. For this purpose, the formation of arsenic trioxide was assessed by micro Fourier transform infrared (μ-FTIR) spectroscopy while the influence of the binder on the formation of sulfates was studied by means of synchrotron radiation X-ray near edge structure (μ-XANES). Both techniques elucidate a higher stability of all pigments in gum arabic while the use of egg yolk as binder leads to the most degradation, most likely due to its sulfur-rich composition. In the context of the degradation of arsenic sulfide pigments, other binders such as animal glue, egg white or linseed oil show an intermediate impact. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000428103000010 |
Publication Date |
2018-01-06 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.034 |
Times cited |
4 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This research is made possible with the support of the Belgian Science Policy Office (BELSPO, Brussels) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (grant number SD/RI/04A). We gratefully acknowledge Megane Willems (Institut Paul-Lambin) for her help with mu-FFIR analyses and realization of the mock-up paint samples. We acknowledge the Paul Scherrer Institut, Villigen, Switzerland for provision of synchrotron radiation beamtime at beamline Phoenix of the SLS. ; |
Approved |
Most recent IF: 3.034 |
Call Number |
UA @ admin @ c:irua:150149 |
Serial |
5482 |
Permanent link to this record |
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|
Author |
Vermeulen, M.; Sanyova, J.; Janssens, K.; Nuyts, G.; De Meyer, S.; De Wael, K. |
Title |
The darkening of copper- or lead-based pigments explained by a structural modification of natural orpiment : a spectroscopic and electrochemical study |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
Volume |
32 |
Issue |
7 |
Pages |
1331-1341 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A combined Raman and electrochemical study of natural orpiment (As2S3), an arsenic sulfide pigment, was used to assess the quick formation of oxidized species such as arsenic oxide (As2O3) upon exposing the pigment to 405 nm or 532 nm monochromatic light while simultaneously recording the Raman spectra of the exposed sample. During this process, a distortion of the main band at 355 cm−1, associated with the stretching of the AsS3/2 pyramids of natural orpiment, was observed as well as an increased intensity of the 359 cm−1 band, corresponding to covalent AsAs bonds in natural orpiment. The distortion was accompanied by an overall decrease of the global Raman signal for natural orpiment, which could be explained by a loss in the crystal structure. The same phenomena were recorded in reference natural orpiment model paint samples stored for a long time together with verdigris (Cu(OH)2·(CH3COO)2·5H2O) and minium (Pb3O4) paints, the latter two appearing darkened on their sides closest to the orpiment sample as well as in several historical samples containing natural orpiment mixed with various blue pigments. By SEM-EDX and XRPD analysis, respectively on loose material and cast thin-sections of model paint samples, the darkening was identified as dark sulfide species such as chalcocite (Cu2S) and galena (PbS), suggesting the release of volatile sulfide or related species by the natural orpiment paint. XANES analyses of paint samples presenting AsAs bond increase indicated the presence of sulfur species most likely identified as organosulfur compounds formed upon the AsAs bond formation and explained the darkening of the Cu- and Pb-based pigments. To the best of our knowledge, this article reports for the first time the light-induced formation of AsAs bonds in natural orpiment used as an artists' pigment and objectively demonstrates the incompatibility between orpiment and (arsenic) sulfide-sensitive pigments. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000404998500007 |
Publication Date |
2017-05-31 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.379 |
Times cited |
10 |
Open Access |
|
Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This research is made possible with the support of the Belgian Science Policy Office (BELSPO, Brussels) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (SD/RI/04A). We gratefully acknowledge Julie Arslanoglu (Conservation and Scientific Research Department at the Metropolitan Museum of Art, New York, USA) for providing us the orpiment, verdigris and minium mock-up samples. We gratefully acknowledge the Paul Scherrer Institut, Villigen, Switzerland and the German Electron Synchrotron (DESY) for provision of synchrotron radiation beamtimes at respectively beamlines of the SLS and Petra III. ; |
Approved |
Most recent IF: 3.379 |
Call Number |
UA @ admin @ c:irua:144384 |
Serial |
5564 |
Permanent link to this record |
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|
|
Author |
Vermeulen, M.; Saverwyns, S.; Coudray, A.; Janssens, K.; Sanyova, J. |
Title |
Identification by Raman spectroscopy of pararealgar as a starting material in the synthesis of amorphous arsenic sulfide pigments |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Dyes and pigments |
Abbreviated Journal |
Dyes Pigments |
Volume |
149 |
Issue |
149 |
Pages |
290-297 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In this study, a combination of elemental analytical techniques (MA-XRF and SEM-EDX) were used to localize arsenic sulfide pigments within a 17th-century Dutch painting and in the stratigraphy of an 18th-century Flemish polychrome sculpture. Once located, Raman spectroscopy was used to obtain the vibrational signature of the arsenic sulfide pigments employed. By means of the latter analytical technique and due to the very distinctive Raman scattering signal of the various arsenic sulfide compounds, it was possible to identify the arsenic-based pigments as natural orpiment and amorphous arsenic sulfide. In the latter case, based on the minor bands observed and the good condition of the paint layers, it was possible to identify pararealgar, the orangey-yellow to yellow degradation product of realgar, as the initial arsenic sulfide material used for the synthesis of the amorphous pigment. To the best of our knowledge, this is the first time that combined pararealgar/amorphous arsenic sulfide Raman spectra are reported in historical samples. Therefore, this would be the first identification of pararealgar as the starting material to produce amorphous, arsenic sulfide pigments used in artworks. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000423246900033 |
Publication Date |
2017-10-12 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0143-7208 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.473 |
Times cited |
7 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This research is made possible with the support of the Belgian Science Policy Office (BELSPO, Brussels) through the research program Science for a Sustainable Development SDD: “Long-term role and fate of metal -sulfides in painted works of art S2ART” (SD/RI/04A). The authors would like to acknowledge the owner of the Abraham Mignon painting, Cecile Glaude for her help with SEM-EDX analyses as well as Livia Depuyt, Carlota Barbosa and Athanasia Fragkou for their assistance. The authors also acknowledge Dr. Karel Palka and Prof. Miroslav Week for their help with the synthesis of the amorphous arsenic sulfide references. ; |
Approved |
Most recent IF: 3.473 |
Call Number |
UA @ admin @ c:irua:149307 |
Serial |
5648 |
Permanent link to this record |
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Author |
Janssens, K.; van der Snickt, G.; Alfeld, M.; Noble, P.; van Loon, A.; Delaney, J.; Conover, D.; Zeibel, J.; Dik, J. |
Title |
Rembrandt's 'Saul and David' (c. 1652) : use of multiple types of smalt evidenced by means of non-destructive imaging |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
Volume |
126 |
Issue |
|
Pages |
515-523 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The painting Saul and David, considered to date from c. 1652 and previously attributed to Rembrandt van Rijn and/or his studio, is a complex work of art that has been recently subjected to intensive investigation and conservation treatment. The goal of the research was to give insight into the painting's physical construction and condition in preparation for conservation treatment. It was also anticipated that analysis would shed light on authenticity questions and Rembrandt's role in the creation of the painting. The painting depicts the Old Testament figures of King Saul and David. At left is Saul, seated, holding a spear and wiping a tear from his eye with a curtain. David kneels before him at the right playing his harp. In the past, the large sections with the life-size figures were cut apart and later reassembled. A third piece of canvas was added to replace a missing piece of canvas above the head of David. As part of the investigation into the authenticity of the curtain area, a number of paint micro samples were examined with LM and SEM-EDX. Given that the earth, smalt and lake pigments used in the painting could not be imaged with traditional imaging techniques, the entire painting was also examined with state of the art non-destructive imaging techniques. Special attention was devoted to the presence of cobalt-containing materials, specifically the blue glass pigment smalt considered characteristic for the late Rembrandt. A combination of quantitative electron microprobe analysis and macroscopic X-ray fluorescence scanning revealed that three types of cobalt-containing materials are present in the painting. The first type is a cobalt drier that was found in the overpaint used to cover up the canvas inset and the joins that were added in the 19th century. The other two Co-containing materials are part of the original paint used by Rembrandt and comprise two varieties of smalt, a K-rich glass pigment that derives its gray-blue color by doping with Co-ions. Smalt paint with a higher Ni content (NiO:CoO ratio of around 1:4) was used to depict the blue stripes in Saul's colorful turban, while smalt with a lower Ni content was employed (NiO:CoO ratio of around 1:5) for the broad expanses of Saul's garments. The presence of two types of smalt not only supports the recent re-attribution of the painting to Rembrandt, but also that the picture was painted in two phases. Saul's dark red garment is painted in a rough, “loose” manner and the now discolored smalt-rich layer was found to have been partially removed during a past restoration treatment/s. In contrast, the blue-green smalt in the turban is much better preserved and provides a colorful accent. While the use of different types of smalt in a Rembrandt painting has been previously identified using quantitative EDX analysis of paint cross-sections, to the best of our knowledge this is the first time such a distinction has been observed in a 17th-century painting using non-destructive imaging techniques. In addition to the XRF-based non-invasive elemental mapping, hyperspectral imaging in the visual to near-infrared (VNIR) region was also carried out. (C) 2016 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000373647500063 |
Publication Date |
2016-01-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0026-265x; 0026-265x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.034 |
Times cited |
18 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This research is part of the ReVisualising late Rembrandt: Developing and Applying New Imaging Techniques research project, supported by the Science4Arts research program of the Netherlands Organisation for Scientific Research (NWO, The Hague, NL, ReVisRembrandt project) and the National Science Foundation (NSF, Washington DC, USA, award 1041827). We would like to thank colleagues of the Mauritshuis (The Hague, NL) and the Dutch Cultural Heritage Agency (RCE) in Rijswijk, NL for their support and assistance during the scanning of the Saul and David painting. The GOA project “SOLARPAINT” (University of Antwerp) and the Fund Baillet Latour (Brussels, B) are acknowledged for financial support to GvdS and KJ. We also like to acknowledge the help of Eliza Longhini and Stijn Legrand during some of the XRF scanning stages. ; |
Approved |
Most recent IF: 3.034 |
Call Number |
UA @ admin @ c:irua:133258 |
Serial |
5813 |
Permanent link to this record |
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Author |
Hellar-Kihampa, H.; De Wael, K.; Lugwisha, E.; Govindan, M.; Covaci, A.; Van Grieken, R. |
Title |
Spatial monitoring of organohalogen compounds in surface water and sediments of a rural-urban river basin in Tanzania |
Type |
A1 Journal article |
Year |
2013 |
Publication |
The science of the total environment |
Abbreviated Journal |
Sci Total Environ |
Volume |
447 |
Issue |
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Pages |
186-197 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
Abstract |
The presence of persistent organic pollutants in Tanzanian environment is not well monitored despite the existing pollution potential from a number of sources. In this study, we investigated for the first time, the concentration profiles of different organohalogen compounds such as organochlorine pesticide residues (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in environmental samples (water and sediments) from the Pangani river basin (PRB). The PRB is one of the largest drainage basins in Tanzania, with its watershed exposed to multiple input sources of trace organic contaminants. Surface water and sediments were sampled from 12 representative stations of diverse characteristics and land-use practices, in three distinct seasons, and extracted by liquidliquid and Soxhlet extraction methods, respectively. Water samples were analyzed by GC-ECD for OCPs only, while sediment samples were analyzed for OCPs, PCBs and PBDEs by GC/MS. Seven compounds, dominated by HCH isomers (5104460 pg/L) and DDT analogs (1601460 pg/L),were detected in the water samples. These concentrations are far below the WHO guidelines for drinking water quality. A total of 42 compounds (8 OCPs, 28 PCB congeners and 6 PBDE congeners) were detected in the sediment samples. Their respective total concentration ranges were 24510,230; 35711,000 and 382175 pg/g dry weight. The spatial distribution patterns and Hierarchical Cluster Analysis reflected the impact of historical agricultural usage in sugarcane plantations (OCPs), and urbanization (PCBs and PBDEs). Risk assessment using sediment quality guidelines indicated no ecotoxicological risks. The results we have found provide preliminary data on levels of the organic contaminants in Pangani river basin as a new insight on the environmental quality of the area. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000317538100022 |
Publication Date |
2013-02-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0048-9697 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.9 |
Times cited |
42 |
Open Access |
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Notes ![sorted by Notes field, ascending order (up)](img/sort_asc.gif) |
; This research project was funded by the International Foundation for Science (IFS, Project Number W/4945-1). The authors wish to acknowledge the contribution of the Pangani Basin Water Office (PBWO) in Moshi, Tanzania; especially Ms. Arafa Maggidi in provision of valuable information and assistance with the sampling campaigns, and Salim Lyimo in mapping of the study area. The contributions of Mr. Peter Machibya of the Department of Geology, University of Dar es Salaam, Tanzania in sediment characterization; and Mr. Emmanuel Gwae, of the Government Chemists Laboratory Agency (GCLA) Dar es Salaam, Tanzania, for instrumental analysis of the water samples, are highly appreciated. Harieth Hellar-Kihampa acknowledges financial support from the Belgian Technical Agency (BTC). Govindan Malarvannan and Adrian Covaci acknowledge financial support from the University of Antwerp. ; |
Approved |
Most recent IF: 4.9; 2013 IF: 3.163 |
Call Number |
UA @ admin @ c:irua:105260 |
Serial |
5836 |
Permanent link to this record |