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Author Nerantzaki, M.; Filippousi, M.; Van Tendeloo, G.; Terzopoulou, Z.; Bikiaris, D.; Goudouri, O.M.; Detsch, R.; Grueenewald, A.; Boccaccini, A.R.
Title Novel poly(butylene succinate) nanocomposites containing strontium hydroxyapatite nanorods with enhanced osteoconductivity for tissue engineering applications Type A1 Journal article
Year 2015 Publication Express polymer letters Abbreviated Journal Express Polym Lett
Volume 9 Issue 9 Pages 773-789
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Three series of poly(butylene succinate) (PBSu) nanocomposites containing 0.5, 1 and 2.5 wt% strontium hydroxyapatite [Sr-5(PO4)(3)OH] nanorods (SrHAp nrds) were prepared by in situ polymerisation. The structural effects of Sr-5(PO4)(3)OH nanorods, for the different concentrations, inside the polymeric matrix (PBSu), were studied through high angle annular dark field scanning transmission electron microscopy (HAADF-STEM). HAADF-STEM measurements revealed that the SrHAp nanorods at low concentrations are dispersed inside the polymeric PBSu matrix while in 1 wt% some aggregates are formed. These aggregations affect the mechanical properties giving an enhancement for the concentration of 0.5 wt% SrHAp nrds in tensile strength, while a reduction is recorded for higher loadings of the nanofiller. Studies on enzymatic hydrolysis revealed that all nanocomposites present higher hydrolysis rates than neat PBSu, indicating that nanorods accelerate the hydrolysis degradation process. In vitro bioactivity tests prove that SrHAp nrds promote the formation of hydroxyapatite on the PBSu surface. All nanocomposites were tested also in relevant cell culture using osteoblast-like cells (MG-63) to demonstrate their biocompatibility showing SrHAp nanorods support cell attachment.
Address
Corporate Author Thesis
Publisher Budapest University of Technology and Economics Department of Polymer Engineering Place of Publication Budapest, Hungary Editor
Language Wos 000357287800004 Publication Date 2015-06-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1788-618X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.983 Times cited (down) 21 Open Access
Notes 262348 Esmi Approved Most recent IF: 2.983; 2015 IF: 2.761
Call Number c:irua:127009 Serial 2382
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Author Adami, O.-A.; Jelić, Ž.L.; Xue, C.; Abdel-Hafiez, M.; Hackens, B.; Moshchalkov, V.V.; Milošević, M.V.; Van de Vondel, J.; Silhanek, A.V.
Title Onset, evolution, and magnetic braking of vortex lattice instabilities in nanostructured superconducting films Type A1 Journal article
Year 2015 Publication Physical review: B: condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 134506
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In 1976, Larkin and Ovchinnikov [Zh. Eksp. Teor. Fiz. 68, 1915 (1975) [Sov. Phys.–JETP 41, 960 (1976)]] predicted that vortex matter in superconductors driven by an electrical current can undergo an abrupt dynamic transition from a flux-flow regime to a more dissipative state at sufficiently high vortex velocities. Typically, this transition manifests itself as a large voltage jump at a particular current density, so-called instability current density J∗, which is smaller than the depairing current. By tuning the effective pinning strength in Al films, using an artificial periodic pinning array of triangular holes, we show that a unique and well-defined instability current density exists if the pinning is strong, whereas a series of multiple voltage transitions appear in the relatively weaker pinning regime. This behavior is consistent with time-dependent Ginzburg-Landau simulations, where the multiple-step transition can be unambiguously attributed to the progressive development of vortex chains and subsequently phase-slip lines. In addition, we explore experimentally the magnetic braking effects, caused by a thick Cu layer deposited on top of the superconductor, on the instabilities and the vortex ratchet effect.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000362433200003 Publication Date 2015-10-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited (down) 21 Open Access
Notes ACKNOWLEDGMENTS: This work was partially supported by the Fonds de la Recherche Scientifique-FNRS, the Methusalem Funding of the Flemish Government, the Research Foundation-Flanders (FWO), and COST Action MP1201. The work of A.V.S. and Z.L.J. is partially supported by “Mandat d’Impulsion Scientifique” MIS F.4527.13 of the F.R.S.-FNRS. B.H. is an associate researcher of the Fonds de la Recherche Scientifique- FNRS. The authors thank J. Cuppens for the data analysis at the early stage of this work, R. Delamare for his valuable help during the fabrication of the samples, and G. Grimaldi for helpful discussions. Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number c:irua:128747 Serial 3981
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Author da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M.
Title Energy levels of bilayer graphene quantum dots Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 115437
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Within a tight binding approach we investigate the energy levels of hexagonal and triangular bilayer graphene (BLG) quantum dots (QDs) with zigzag and armchair edges. We study AA- and AB-(Bernal) stacked BLG QDs and obtain the energy levels in both the absence and the presence of a perpendicular electric field (i.e., biased BLG QDs). Our results show that the size dependence of the energy levels is different from that of monolayer graphene QDs. The energy spectrum of AB-stacked BLG QDs with zigzag edges exhibits edge states which spread out into the opened energy gap in the presence of a perpendicular electric field. We found that the behavior of these edges states is different for the hexagonal and triangular geometries. In the case of AA-stacked BLG QDs, the electron and hole energy levels cross each other in both cases of armchair and zigzag edges as the dot size or the applied bias increases.
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Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000361663700003 Publication Date 2015-09-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited (down) 21 Open Access
Notes ; This work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the process number BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:128726 Serial 4173
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Author Michel, K.H.; Costamagna; Peeters, F.M.
Title Theory of thermal expansion in 2D crystals Type A1 Journal article
Year 2015 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B
Volume 252 Issue 252 Pages 2433-2437
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The thermal expansion alpha(T) in layered crystals is of fundamental and technological interest. As suggested by I. M. Lifshitz in 1952, in thin solid films (crystalline membranes) a negative contribution to alpha(T) is due to anharmonic couplings between in-plane stretching modes and out-of-plane bending (flexural modes). Genuine in-plane anharmonicities give a positive contribution to alpha(T). The competition between these two effects can lead to a change of sign (crossover) from a negative value of alpha(T) in a temperature (T) range T <= T-alpha to a positive value of alpha(T) for T > T-alpha in layered crystals. Here, we present an analytical lattice dynamical theory of these phenomena for a two-dimensional (2D) hexagonal crystal. We start from a Hamiltonian that comprises anharmonic terms of third and fourth order in the lattice displacements. The in-plane and out-of-plane contributions to the thermal expansion are studied as functions of T for crystals of different sizes. Besides, renormalization of the flexural mode frequencies plays a crucial role in determining the crossover temperature T-alpha. Numerical examples are given for graphene where the anharmonic couplings are determined from experiments. The theory is applicable to other layer crystals wherever the anharmonic couplings are known. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000364690400014 Publication Date 2015-08-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-1972 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.674 Times cited (down) 21 Open Access
Notes ; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the Euro GRAPHENE project CONGRAN. ; Approved Most recent IF: 1.674; 2015 IF: 1.489
Call Number UA @ lucian @ c:irua:130281 Serial 4264
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Author Hamidi-Asl, E.; Dardenne, F.; Blust, R.; De Wael, K.
Title An improved electrochemical aptasensor for chloramphenicol detection based on aptamer incorporated gelatine Type A1 Journal article
Year 2015 Publication Sensors Abbreviated Journal Sensors-Basel
Volume 15 Issue 4 Pages 7605-7618
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Because of the biocompatible properties of gelatine and the good affinity of aptamers for their targets, the combination of aptamer and gelatine type B is reported as promising for the development of biosensing devices. Here, an aptamer for chloramphenicol (CAP) is mixed with different types of gelatine and dropped on the surface of disposable gold screen printed electrodes. The signal of the CAP reduction is investigated using differential pulse voltammetry. The diagnostic performance of the sensor is described and a detection limit of 1.83 x 10(-10) M is found. The selectivity and the stability of the aptasensor are studied and compared to those of other CAP sensors described in literature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000354236100025 Publication Date 2015-03-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1424-8220 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.677 Times cited (down) 21 Open Access
Notes ; Ezat Hamidi-Asl was financially supported by IOF-POC (University of Antwerp). ; Approved Most recent IF: 2.677; 2015 IF: 2.245
Call Number UA @ admin @ c:irua:126071 Serial 5464
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Author Lu, Y.-G.; Turner, S.; Ekimov, E.A.; Verbeeck, J.; Van Tendeloo, G.
Title Boron-rich inclusions and boron distribution in HPHT polycrystalline superconducting diamond Type A1 Journal article
Year 2015 Publication Carbon Abbreviated Journal Carbon
Volume 86 Issue 86 Pages 156-162
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Polycrystalline boron-doped superconducting diamond, synthesized at high pressure and high temperature (HPHT) via a reaction of a single piece of crystalline boron with monolithic graphite, has been investigated by analytical transmission electron microscopy. The local boron distribution and boron environment have been studied by a combination of (scanning) transmission electron microscopy ((S)TEM) and spatially resolved electron energy-loss spectroscopy (EELS). High resolution TEM imaging and EELS elemental mapping have established, for the first time, the presence of largely crystalline diamond-diamond grain boundaries within the material and have evidenced the presence of substitutional boron dopants within individual diamond grains. Confirmation of the presence of substitutional B dopants has been obtained through comparison of acquired boron K-edge EELS fine structures with known references. This confirmation is important to understand the origin of superconductivity in polycrystalline B-doped diamond. In addition to the substitutional boron doping, boron-rich inclusions and triple-points, both amorphous and crystalline, with chemical compositions close to boron carbide B4C, are evidenced. (C) 2015 Elsevier Ltd. All rights reserved.
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Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000352922700019 Publication Date 2015-01-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited (down) 20 Open Access
Notes FWO; 246791 COUNTATOMS; 278510 VORTEX; Hercules ECASJO_; Approved Most recent IF: 6.337; 2015 IF: 6.196
Call Number c:irua:125994UA @ admin @ c:irua:125994 Serial 250
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Author Xie, L.; Brault, P.; Coutanceau, C.; Bauchire, J.-M.; Caillard, A.; Baranton, S.; Berndt, J.; Neyts, E.C.
Title Efficient amorphous platinum catalyst cluster growth on porous carbon : a combined molecular dynamics and experimental study Type A1 Journal article
Year 2015 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ
Volume 162 Issue 162 Pages 21-26
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Amorphous platinum clusters supported on porous carbon have been envisaged for high-performance fuel cell electrodes. For this application, it is crucial to control the morphology of the Pt layer and the Ptsubstrate interaction to maximize activity and stability. We thus investigate the morphology evolution during Pt cluster growth on a porous carbon substrate employing atomic scale molecular dynamics simulations. The simulations are based on the Pt-C interaction potential using parameters derived from density functional theory and are found to yield a Pt cluster morphology similar to that observed in low loaded fuel cell electrodes prepared by plasma sputtering. Moreover, the simulations show amorphous Pt cluster growth in agreement with X-ray diffraction and transmission electron microscopy experiments on high performance low Pt content (10 μgPt cm−2) loaded fuel cell electrodes and provide a fundamental insight in the cluster growth mechanism.
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Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000343686900003 Publication Date 2014-06-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0926-3373; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.446 Times cited (down) 20 Open Access
Notes Approved Most recent IF: 9.446; 2015 IF: 7.435
Call Number c:irua:117949 Serial 874
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Author Angelakeris, M.; Li, Z.A.; Hilgendorff, M.; Simeonidis, K.; Sakellari, D.; Filippousi, M.; Tian, H.; Van Tendeloo, G.; Spasova, M.; Acet, M.; Farle, M.
Title Enhanced biomedical heat-triggered carriers via nanomagnetism tuning in ferrite-based nanoparticles Type A1 Journal article
Year 2015 Publication Journal of magnetism and magnetic materials Abbreviated Journal J Magn Magn Mater
Volume 381 Issue 381 Pages 179-187
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Biomedical nanomagnetic carriers are getting a higher impact in therapy and diagnosis schemes while their constraints and prerequisites are more and more successfully confronted. Such particles should possess a well-defined size with minimum agglomeration and they should be synthesized in a facile and reproducible high-yield way together with a controllable response to an applied static or dynamic field tailored for the specific application. Here, we attempt to enhance the heating efficiency in magnetic particle hyperthermia treatment through the proper adjustment of the core-shell morphology in ferrite particles, by controlling exchange and dipolar magnetic interactions at the nanoscale. Thus, core-shell nanoparticles with mutual coupling of magnetically hard (CoFe2O4) and soft (MnFe2O4) components are synthesized with facile synthetic controls resulting in uniform size and shell thickness as evidenced by high resolution transmission electron microscopy imaging, excellent crystallinity and size monodispersity. Such a magnetic coupling enables the fine tuning of magnetic anisotropy and magnetic interactions without sparing the good structural, chemical and colloidal stability. Consequently, the magnetic heating efficiency of CoFe2O4. and MnFe2O4 core-shell nanoparticles is distinctively different horn that of their counterparts, even though all these nanocrystals were synthesized under similar conditions. For better understanding of the AC magnetic hyperthermia response and its correlation with magnetic-origin features we study the effect of the volume ratio of magnetic hard and soft phases in the bimagnetic core-shell nanocrystals. Eventually, such particles may be considered as novel heating carriers that under further biomedical functionalization may become adaptable multifunctional heat-triggered nanoplatforms. (C) 2014 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000349361100027 Publication Date 2014-12-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-8853; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.63 Times cited (down) 20 Open Access
Notes 312483 Esteem2; Esteem2_ta Approved Most recent IF: 2.63; 2015 IF: 1.970
Call Number c:irua:125284 c:irua:125284 Serial 1049
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Author Pizzochero, M.; Leenaerts, O.; Partoens, B.; Martinazzo, R.; Peeters, F.M.
Title Hydrogen adsorption on nitrogen and boron doped graphene Type A1 Journal article
Year 2015 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 27 Issue 27 Pages 425502
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Hydrogen adsorption on boron and nitrogen doped graphene is investigated in detail by means of first-principles calculations. A comprehensive study is performed of the structural, electronic, and magnetic properties of chemisorbed hydrogen atoms and atom pairs near the dopant sites. The main effect of the substitutional atoms is charge doping which is found to greatly affect the adsorption process by increasing the binding energy at the sites closest to the substitutional species. It is also found that doping does not induce magnetism despite the odd number of electrons per atom introduced by the foreign species, and that it quenches the paramagnetic response of chemisorbed H atoms on graphene. Overall, the effects are similar for B and N doping, with only minor differences in the adsorption energetics due to different sizes of the dopant atoms and the accompanying lattice distortions.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000362573500008 Publication Date 2015-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited (down) 20 Open Access
Notes This work was supported by the Flemish Science Foundation (FWO-Vl). MP gratefully acknowledges the Condensed Matter Theory group at Universiteit Antwerpen for the hospitality during his stay. Approved Most recent IF: 2.649; 2015 IF: 2.346
Call Number c:irua:128759 Serial 3971
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Author Lukyanchuk, I.; Vinokur, V.M.; Rydh, A.; Xie, R.; Milošević, M.V.; Welp, U.; Zach, M.; Xiao, Z.L.; Crabtree, G.W.; Bending, S.J.; Peeters, F.M.; Kwok, W.K.
Title Rayleigh instability of confined vortex droplets in critical superconductors Type A1 Journal article
Year 2015 Publication Nature physics Abbreviated Journal Nat Phys
Volume 11 Issue 11 Pages 21-25
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Depending on the Ginzburg-Landau parameter kappa, superconductors can either be fully diamagnetic if kappa < 1/root 2 (type I superconductors) or allow magnetic flux to penetrate through Abrikosov vortices if kappa > 1/root 2 (type II superconductors; refs 1,2). At the Bogomolny critical point, kappa = kappa(c) = 1/root 2, a state that is infinitely degenerate with respect to vortex spatial configurations arises(3,4). Despite in-depth investigations of conventional type I and type II superconductors, a thorough understanding of the magnetic behaviour in the near-Bogomolny critical regime at kappa similar to kappa(c) remains lacking. Here we report that in confined systems the critical regime expands over a finite interval of kappa forming a critical superconducting state. We show that in this state, in a sample with dimensions comparable to the vortex core size, vortices merge into a multi-quanta droplet, which undergoes Rayleigh instability(5) on increasing kappa and decays by emitting single vortices. Superconducting vortices realize Nielsen-Olesen singular solutions of the Abelian Higgs model, which is pervasive in phenomena ranging from quantum electrodynamics to cosmology(6-9). Our study of the transient dynamics of Abrikosov-Nielsen-Olesen vortices in systems with boundaries promises access to non-trivial effects in quantum field theory by means of bench-top laboratory experiments.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000346831100018 Publication Date 2014-11-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1745-2473;1745-2481; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 22.806 Times cited (down) 20 Open Access
Notes ; We would like to thank N. Nekrasov for illuminating discussions. The work was supported by the US Department of Energy, Office of Science Materials Sciences and Engineering Division (V.M.V., W.K.K., U.W., R.X., M.Z., Z.L.X., G.W.C. and partially I.L. through the Materials Theory Institute), by FP7-IRSES-SIMTECH and ITN-NOTEDEV programs (I.L.), and by the Flemish Science Foundation (FWO-Vlaanderen) (M.V.M. and F.M.P.). ; Approved Most recent IF: 22.806; 2015 IF: 20.147
Call Number c:irua:122791 c:irua:122791 Serial 2815
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Author Van der Paal, J.; Verlackt, C.C.; Yusupov, M.; Neyts, E.C.; Bogaerts, A.
Title Structural modification of the skin barrier by OH radicals : a reactive molecular dynamics study for plasma medicine Type A1 Journal article
Year 2015 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 48 Issue 48 Pages 155202
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract While plasma treatment of skin diseases and wound healing has been proven highly effective, the underlying mechanisms, and more generally the effect of plasma radicals on skin tissue, are not yet completely understood. In this paper, we perform ReaxFF-based reactive molecular dynamics simulations to investigate the interaction of plasma generated OH radicals with a model system composed of free fatty acids, ceramides, and cholesterol molecules. This model system is an approximation of the upper layer of the skin (stratum corneum). All interaction mechanisms observed in our simulations are initiated by H-abstraction from one of the ceramides. This reaction, in turn, often starts a cascade of other reactions, which eventually lead to the formation of aldehydes, the dissociation of ceramides or the elimination of formaldehyde, and thus eventually to the degradation of the skin barrier function.
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Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000351856600007 Publication Date 2015-03-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited (down) 20 Open Access
Notes Approved Most recent IF: 2.588; 2015 IF: 2.721
Call Number c:irua:124230 Serial 3242
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Author Sun, M.; Rousse, G.; Abakumov, A.M.; Saubanere, M.; Doublet, M.-L.; Rodriguez-Carvajal, J.; Van Tendeloo, G.; Tarascon, J.-M.
Title Li2Cu2O(SO4)2: a possible electrode for sustainable Li-based batteries showing a 4.7 V redox activity vs Li+/Li0 Type A1 Journal article
Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 27 Issue 27 Pages 3077-3087
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Li-ion batteries rely on the use of insertion positive electrodes with performances scaling with the redox potential of the 31) metals accompanying Liuptake/removal. Although not commonly studied, the Cu2+/Cu3+ redox potential has been predicted from theoretical calculations to possibly offer a high operating voltage redox couple. We herein report the synthesis and crystal structure of a hitherto-unknown oxysulfate phase, Li2Cu2O(SO4)(2), which contains infinite edgesharing CuO4 chains and presents attractive electrochemical redox activity with respect to Li+/Li, namely amphoteric characteristics. Li2Cu2O(SO4)(2) shows redox activity at 4.7 V vs Li+/Li corresponding to the oxidation of Cu2+ to Cu3+ enlisting ligand holes and associated with the reversible uptake-removal of 0.3 Li. Upon reduction, this compound reversibly uptakes similar to 2 Li at an average potential of about 2.5 V vs Li+/Li, associated with the Cu2+/Cu+ redox couple. The mechanism of the reactivity upon reduction is discussed in detail, with particular attention to the occasional appearance of an oscillation wave in the discharge profile. Our work demonstrates that Cu-based compounds can indeed be fertile scientific ground in the search for new high-energy-density electrodes.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000353865800043 Publication Date 2015-03-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited (down) 20 Open Access
Notes Approved Most recent IF: 9.466; 2015 IF: 8.354
Call Number c:irua:126061 Serial 3541
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Author Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
Title The role of the VZn-NO-H complex in the p-type conductivity in ZnO Type A1 Journal article
Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 17 Issue 17 Pages 5485-5489
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000349616400080 Publication Date 2015-01-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076;1463-9084; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited (down) 20 Open Access
Notes FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules Approved Most recent IF: 4.123; 2015 IF: 4.493
Call Number c:irua:123218 Serial 3592
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Author Ozaydin, H.D.; Sahin, H.; Kang, J.; Peeters, F.M.; Senger, R.T.
Title Electronic and magnetic properties of 1T-TiSe2 nanoribbons Type A1 Journal article
Year 2015 Publication 2D materials Abbreviated Journal 2D Mater
Volume 2 Issue 2 Pages 044002
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Motivated by the recent synthesis of single layer TiSe2, we used state-of-the-art density functional theory calculations, to investigate the structural and electronic properties of zigzag and armchair-edged nanoribbons (NRs) of this material. Our analysis reveals that, differing from ribbons of other ultra-thin materials such as graphene, TiSe2 NRs have some distinctive properties. The electronic band gap of the NRs decreases exponentially with the width and vanishes for ribbons wider than 20 angstrom. For ultranarrow zigzag-edged NRs we find odd-even oscillations in the band gap width, although their band structures show similar features. Moreover, our detailed magnetic-ground-state analysis reveals that zigzag and armchair edged ribbons have non-magnetic ground states. Passivating the dangling bonds with hydrogen at the edges of the structures influences the band dispersion. Our results shed light on the characteristic properties of T phase NRs of similar crystal structures.
Address
Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos 000368936600005 Publication Date 2015-10-13
Series Editor Series Title Abbreviated Series Title
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 (down) 20 Open Access
Notes ; 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 ULAK-BIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus Short Marie Curie Fellowship. HDO, HS and RTS acknowledge the support from TUBITAK through project 114F397. ; Approved Most recent IF: 6.937; 2015 IF: NA
Call Number UA @ lucian @ c:irua:131602 Serial 4169
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Author Ceglia, A.; Nuyts, G.; Meulebroeck, W.; Cagno, S.; Silvestri, A.; Zoleo, A.; Nys, K.; Janssens, K.; Thienpont, H.; Terryn, H.
Title Iron speciation in soda-lime-silica glass: a comparison of XANES and UV-vis-NIR spectroscopy Type A1 Journal article
Year 2015 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom
Volume 30 Issue 7 Pages 1552-1561
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Scientific analyses of ancient glasses have been carried out for many years using elemental chemical analysis. However, it is known that the control of the redox conditions in the glass melt has a strong implication on the final hue of glass because it affects Fe2+/SFe. Therefore an increasing number of studies on the redox conditions have been published in recent years by means of synchrotron based Xray absorption spectroscopy. This is a technique which is not easily accessible and requires dedicated facilities. In this paper we describe an alternative approach by means of optical absorption spectroscopy. We synthesised 10 soda-lime-silica glasses with known redox conditions and iron concentration to calibrate the absorption at 1100 nm as a function of Fe2+ concentration. The linear extinction coefficient was also determined. These glasses were also studied by means of X-ray Absorption Near Edge Structure (XANES) spectroscopy. Electron paramagnetic resonance spectroscopy was additionally used as an ancillary method to verify the quality of our data. Furthermore 28 samples from real archaeological samples were analysed by XANES and optical spectroscopy as a case study. The Fe2+/SFe values obtained were compared and demonstrated that the two techniques were in good agreement with each other. Optical spectroscopy can be applied in situ with moderate sample preparation to determine the concentration of Fe2+. To investigate the redox conditions, especially as a first screening approach, this methodology is an important tool to take into consideration before applying more sophisticated techniques such as XANES, which is more elaborate and requires high-tech resources.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000356971900009 Publication Date 2015-04-15
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 (down) 20 Open Access
Notes ; The research leading to these results has received funding from the European Union Seventh Framework Programme FP7/2007-2013 under grant agreement no. 265010. For more information please visit the NARNIA website: http:// narnia-itn.eu/. This work was partly supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/ F50. We are grateful to the ESRF for granting beamtime and Dipanjan Banerjee for his help at the beamline. We are thankful to the R&D department of AGC Glass Europe, in particular Dr Benoit Cherdon, Dr Dominique Michiels and Ms Dominique Delleuze, for preparing glass for us and providing us the chemical information. A special thanks to M. Fialin for the help with EPMA measurements in CAMPARIS. We want to express our gratitude to F. Farges and A. Berry for sharing their XANES spectra with us. Thanks to Anne Isabelle for reading this paper and giving comments. Finally we are grateful to two anonymous reviewers who contributed to improve this paper. ; Approved Most recent IF: 3.379; 2015 IF: 3.466
Call Number UA @ admin @ c:irua:127060 Serial 5679
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Author De Henau, S.; Tilleman, L.; Vangheel, M.; Luyckx, E.; Trashin, S.; Pauwels, M.; Germani, F.; Vlaeminck, C.; Vanfleteren, J.R.; Bert, W.; Pesce, A.; Nardini, M.; Bolognesi, M.; De Wael, K.; Moens, L.; Dewilde, S.; Braeckman, B.P.
Title A redox signalling globin is essential for reproduction in Caenorhabditis elegans Type A1 Journal article
Year 2015 Publication Nature communications Abbreviated Journal Nat Commun
Volume 6 Issue Pages 8782
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Moderate levels of reactive oxygen species (ROS) are now recognized as redox signalling molecules. However, thus far, only mitochondria and NADPH oxidases have been identified as cellular sources of ROS in signalling. Here we identify a globin (GLB-12) that produces superoxide, a type of ROS, which serves as an essential signal for reproduction in C. elegans. We find that GLB-12 has an important role in the regulation of multiple aspects in germline development, including germ cell apoptosis. We further describe how GLB-12 displays specific molecular, biochemical and structural properties that allow this globin to act as a superoxide generator. In addition, both an intra- and extracellular superoxide dismutase act as key partners of GLB-12 to create a transmembrane redox signal. Our results show that a globin can function as a driving factor in redox signalling, and how this signal is regulated at the subcellular level by multiple control layers.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000367577100002 Publication Date 2015-12-01
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 12.124 Times cited (down) 20 Open Access
Notes ; We thank Dr K. Matsumoto and Dr T. Mizuno for kindly providing the mek-1(ks54) sek-1(km4) double mutant, the antibody anti-PMK-1 and technical advice on antibody use; Dr D. Kim for kindly providing the pDK177 RNAi strain; Dr M. Ubbink and Dr Q. Bashir for providing CCP; Dr K. Oegema and the OD lab for sharing technical expertise; M. Couvreur for assistance in generating transgenic lines; and Dr T. Dansen for the final support. Some strains were provided by the CGC, which is funded by the NIH Office of Research Infrastructure Programs (P40 OD010440). S.D.H. and F.G. are PhD fellows of the Fund for Scientific Research (FWO). Financial support to S.D. and L.M. was provided by the University of Antwerp (BOF UA TOP 2006), to K.D.W., S.D. and S.T. by the University of Antwerp (BOF-GOA) and to S.D., L.M., B.P.B., by FWO project G.0247.09. ; Approved Most recent IF: 12.124; 2015 IF: 11.470
Call Number UA @ admin @ c:irua:129310 Serial 5809
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Author Berdiyorov, G.; Harrabi, K.; Maneval, J.P.; Peeters, F.M.
Title Effect of pinning on the response of superconducting strips to an external pulsed current Type A1 Journal article
Year 2015 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 28 Issue 28 Pages 025004
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the anisotropic time-dependent Ginzburg-Landau theory we study the effect of ordered and disordered pinning on the time response of superconducting strips to an external current that switched on abruptly. The pinning centers result in a considerable delay of the response time of the system to such abrupt switching on of the current, whereas the output voltage is always larger when pinning is present. The resistive state in both cases are characterized either by dynamically stable phase-slip centers/lines or expanding in-time hot-spots, which are the main mechanisms for dissipation in current-carrying superconductors. We find that hot-spots are always initiated by the phase-slip state. However, the range of the applied current for the phase-slip state increases significantly when pinning is introduced. Qualitative changes are observed in the dynamics of the superconducting condensate in the presence of pinning.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000351046300010 Publication Date 2014-12-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited (down) 19 Open Access
Notes ; This work was supported by EU Marie Curie (Project No: 253057), the Flemish Science Foundation (FWO-Vl) and King Fahd University of Petroleum and Minerals, Saudi Arabia, under the IN131034 DSR project. ; Approved Most recent IF: 2.878; 2015 IF: 2.325
Call Number c:irua:125491 Serial 829
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Author Sankaran, K.; Clima, S.; Mees, M.; Pourtois, G.
Title Exploring alternative metals to Cu and W for interconnects applications using automated first-principles simulations Type A1 Journal article
Year 2015 Publication ECS journal of solid state science and technology Abbreviated Journal Ecs J Solid State Sc
Volume 4 Issue 4 Pages N3127-N3133
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The bulk properties of elementary metals and copper based binary alloys have been investigated using automated first-principles simulations to evaluate their potential to replace copper and tungsten as interconnecting wires in the coming CMOS technology nodes. The intrinsic properties of the screened candidates based on their cohesive energy and on their electronic properties have been used as a metrics to reflect their resistivity and their sensitivity to electromigration. Using these values, the 'performances' of the alloys have been benchmarked with respect to the Cu and W ones. It turns out that for some systems, alloying Cu with another element leads to a reduced tendency to electromigration. This is however done at the expense of a decrease of the conductivity of the alloy with respect to the bulk metal. (C) 2014 The Electrochemical Society. All rights reserved.
Address
Corporate Author Thesis
Publisher Electrochemical society Place of Publication Pennington (N.J.) Editor
Language Wos 000349547900018 Publication Date 2014-11-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2162-8769;2162-8777; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.787 Times cited (down) 19 Open Access
Notes Approved Most recent IF: 1.787; 2015 IF: 1.558
Call Number c:irua:125296 Serial 1150
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Author Milovanović, S.P.; Moldovan, D.; Peeters, F.M.
Title Veselago lensing in graphene with a p-n junction: Classical versus quantum effects Type A1 Journal article
Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 118 Issue 118 Pages 154308
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The feasibility of Veselago lensing in graphene with a p-n junction is investigated numerically for realistic injection leads. Two different set-ups with two narrow leads are considered with absorbing or reflecting side edges. This allows us to separately determine the influence of scattering on electron focusing for the edges and the p-n interface. Both semiclassical and tight-binding simulations show a distinctive peak in the transmission probability that is attributed to the Veselago lensing effect. We investigate the robustness of this peak on the width of the injector, the position of the p-n interface, and different gate potential profiles. Furthermore, the influence of scattering by both short- and long-range impurities is considered.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000363535800022 Publication Date 2015-10-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited (down) 19 Open Access
Notes This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. Approved Most recent IF: 2.068; 2015 IF: 2.183
Call Number c:irua:129452 Serial 3969
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Author Dumpala, S.; Broderick, S.R.; Khalilov, U.; Neyts, E.C.; van Duin, A.C.T.; Provine, J.; Howe, R.T.; Rajan, K.
Title Integrated atomistic chemical imaging and reactive force field molecular dynamic simulations on silicon oxidation Type A1 Journal article
Year 2015 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 106 Issue 106 Pages 011602
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this paper, we quantitatively investigate with atom probe tomography, the effect of temperature on the interfacial transition layer suboxide species due to the thermal oxidation of silicon. The chemistry at the interface was measured with atomic scale resolution, and the changes in chemistry and intermixing at the interface were identified on a nanometer scale. We find an increase of suboxide (SiOx) concentration relative to SiO2 and increased oxygen ingress with elevated temperatures. Our experimental findings are in agreement with reactive force field molecular dynamics simulations. This work demonstrates the direct comparison between atom probe derived chemical profiles and atomistic-scale simulations for transitional interfacial layer of suboxides as a function of temperature.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000347976900008 Publication Date 2015-01-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited (down) 19 Open Access
Notes Approved Most recent IF: 3.411; 2015 IF: 3.302
Call Number c:irua:122300 Serial 1679
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Author Guzzinati, G.; Clark, L.; Béché, A.; Juchtmans, R.; Van Boxem, R.; Mazilu, M.; Verbeeck, J.
Title Prospects for versatile phase manipulation in the TEM : beyond aberration correction Type A1 Journal article
Year 2015 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 151 Issue 151 Pages 85-93
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this paper we explore the desirability of a transmission electron microscope in which the phase of the electron wave can be freely controlled. We discuss different existing methods to manipulate the phase of the electron wave and their limitations. We show how with the help of current techniques the electron wave can already be crafted into specific classes of waves each having their own peculiar properties. Assuming a versatile phase modulation device is feasible, we explore possible benefits and methods that could come into existence borrowing from light optics where the so-called spatial light modulators provide programmable phase plates for quite some time now. We demonstrate that a fully controllable phase plate building on Harald Rose׳s legacy in aberration correction and electron optics in general would open an exciting field of research and applications.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000351237800012 Publication Date 2014-10-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited (down) 19 Open Access
Notes 278510 Vortex; Fwo; 312483 Esteem2; esteem2jra2; esteem2jra3 ECASJO_; Approved Most recent IF: 2.843; 2015 IF: 2.436
Call Number c:irua:121405 c:irua:121405UA @ admin @ c:irua:121405 Serial 2731
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Author Bretos, I.; Schneller, T.; Falter, M.; Baecker, M.; Hollmann, E.; Woerdenweber, R.; Molina-Luna, L.; Van Tendeloo, G.; Eibl, O.
Title Solution-derived YBa2Cu3O7-\delta (YBCO) superconducting films with BaZrO3 (BZO) nanodots based on reverse micelle stabilized nanoparticles Type A1 Journal article
Year 2015 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
Volume 3 Issue 3 Pages 3971-3979
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Superconducting YBa2Cu3O7-delta (YBCO) films with artificial BaZrO3 (BZO) nanodots were prepared using a chemical solution deposition method involving hybrid solutions composed of trifluoroacetate-based YBCO precursors and reverse micelle stabilized BZO nanoparticle dispersions. Microemulsion-mediated synthesis was used to obtain nano-sized (similar to 12 nm) and mono-dispersed BZO nanoparticles that preserve their features once introduced into the YBCO solution, as revealed by dynamic light scattering. Phase pure, epitaxial YBCO films with randomly oriented BZO nanodots distributed over their whole microstructure were grown from the hybrid solutions on (100) LaAlO3 substrates. The morphology of the YBCO-BZO nanocomposite films was strongly influenced by the amount of nanoparticles incorporated into the system, with contents ranging from 5 to 40 mol%. Scanning electron microscopy showed a high density of isolated second-phase defects consisting of BZO nanodots in the nanocomposite film with 10 mol% of BZO. Furthermore, a direct observation and quantitative analysis of lattice defects in the form of interfacial edge dislocations directly induced by the BZO nanodots was evidenced by transmission electron microscopy. The superconducting properties (77 K) of the YBCO films improved considerably by the presence of such nanodots, which seem to enhance the morphology of the sample and therefore the intergranular critical properties. The incorporation of preformed second-phase defects (here, BZO) during the growth of the superconducting phase is the main innovation of this novel approach for the all-solution based low-cost fabrication of long-length coated conductors.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000352870400018 Publication Date 2015-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7526; 2050-7534 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.256 Times cited (down) 19 Open Access
Notes This work was supported by the German Federal Ministry of Economics and Technology (BMWi) contract no. 0327433A (project ELSA). L. Molina-Luna and G. Van Tendeloo acknowledge funding from the European Research Council (ERC grant no. 24691-COUNTATOMS). The authors gratefully acknowledge J. Dornseiffer for the support with preparation of the microemulsions for the BZO nanoparticles; G. Wasse for the SEM images; and T. Po¨ssinger for the preparation of the artwork. Eurotape Approved Most recent IF: 5.256; 2015 IF: 4.696
Call Number UA @ lucian @ c:irua:132575 Serial 4245
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Author Woo, S.Y.; Gauquelin, N.; Nguyen, H.P.T.; Mi, Z.; Botton, G.A.
Title Interplay of strain and indium incorporation in InGaN/GaN dot-in-a-wire nanostructures by scanning transmission electron microscopy Type A1 Journal article
Year 2015 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume 26 Issue 26 Pages 344002
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The interplay between strain and composition is at the basis of heterostructure design to engineer new properties. The influence of the strain distribution on the incorporation of indium during the formation of multiple InGaN/GaN quantum dots (QDs) in nanowire (NW) heterostructures has been investigated, using the combined techniques of geometric phase analysis of atomic-resolution images and quantitative elemental mapping from core-loss electron energy-loss spectroscopy within scanning transmission electron microscopy. The variation in In-content between successive QDs within individual NWs shows a dependence on the magnitude of compressive strain along the growth direction within the underlying GaN barrier layer, which affects the incorporation of In-atoms to minimize the local effective strain energy. Observations suggest that the interfacial misfit between InGaN/GaN within the embedded QDs is mitigated by strain partitioning into both materials, and results in normal stresses inflicted by the presence of the surrounding GaN shell. These experimental measurements are linked to the local piezoelectric polarization fields for individual QDs, and are discussed in terms of the photoluminescence from an ensemble of NWs.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000359079500003 Publication Date 2015-08-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited (down) 19 Open Access
Notes Approved Most recent IF: 3.44; 2015 IF: 3.821
Call Number UA @ lucian @ c:irua:136278 Serial 4504
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Author Wang, Y.; Sentosun, K.; Li, A.; Coronado-Puchau, M.; Sánchez-Iglesias, A.; Li, S.; Su, X.; Bals, S.; Liz-Marzán, L.M.
Title Engineering Structural Diversity in Gold Nanocrystals by Ligand-Mediated Interface Control Type A1 Journal article
Year 2015 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 27 Issue 27 Pages 8032-8040
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Surface and interface control is fundamentally important for crystal growth engineering, catalysis, surface enhanced spectroscopies, and self-assembly, among other processes and applications. Understanding the role of ligands in regulating surface properties of plasmonic metal nanocrystals during growth has received considerable attention. However, the underlying mechanisms and the diverse functionalities of ligands are yet to be fully addressed. In this contribution,

we report a systematic study of ligand-mediated interface control in seeded growth of gold nanocrystals, leading to diverse and exotic nanostructures with an improved surface enhanced Raman scattering (SERS) activity. Three dimensional transmission electron microscopy (3D TEM) revealed an intriguing gold shell growth process mediated by the bifunctional ligand 1,4-benzenedithiol (BDT), which leads to a unique crystal growth mechanism as compared to other ligands, and subsequently to the concept of interfacial energy control mechanism. Volmer-Weber growth mode was proposed to be responsible for BDT-mediated seeded growth, favoring the strongest interfacial energy and generating an asymmetric island growth pathway with internal crevices/gaps. This additionally favors incorporation of BDT at the plasmonic nanogaps, thereby generating strong SERS activity with a maximum efficiency for a core-semishell configuration obtained along seeded growth. Numerical modeling was used to explain this observation. Interestingly, the same strategy can be used to engineer the structural diversity of this system, by using gold nanoparticle seeds with various sizes and shapes, and varying the [Au3+]/[Au0] ratio. This rendered a series of diverse and exotic plasmonic nanohybrids such as semishell-coated gold nanorods, with embedded Raman-active tags and Janus surface with distinct surface functionalities.

These would greatly enrich the plasmonic nanostructure toolbox for various studies and applications such as anisotropic nanocrystal engineering, SERS, and high-resolution Raman bioimaging or nanoantenna devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000366223200023 Publication Date 2015-10-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited (down) 18 Open Access OpenAccess
Notes The authors thank Bart Goris for his help with electron tomography. This work was funded by the European Commission (Grant #310445-2, SAVVY). The authors acknowledge financial support from European Research Council (ERC Advanced Grant # 267867- PLASMAQUO, ERC Starting Grant #335078-COLOURATOMS). The authors also appreciate financial support from the European Union under the Seventh Framework Program (Integrated Infrastructure Initiative N. 262348 European Soft Matter Infrastructure, ESMI). Wang Y. and Su X. would like to acknowledge the Agency for Science, Technology and Research (A*STAR), Singapore, for the financial support under the Grant JCO 14302FG096. M. C.-P. acknowledges an FPU scholarship from the Spanish Ministry of Education, Culture and Sports.; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 9.466; 2015 IF: 8.354
Call Number c:irua:129598 c:irua:129598 Serial 3972
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Author Yusupov, M.; Neyts, E.C.; Verlackt, C.C.; Khalilov, U.; van Duin, A.C.T.; Bogaerts, A.
Title Inactivation of the endotoxic biomolecule lipid A by oxygen plasma species : a reactive molecular dynamics study Type A1 Journal article
Year 2015 Publication Plasma processes and polymers Abbreviated Journal Plasma Process Polym
Volume 12 Issue 12 Pages 162-171
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Reactive molecular dynamics simulations are performed to study the interaction of reactive oxygen species, such as OH, HO2 and H2O2, with the endotoxic biomolecule lipid A of the gram-negative bacterium Escherichia coli. It is found that the aforementioned plasma species can destroy the lipid A, which consequently results in reducing its toxic activity. All bond dissociation events are initiated by hydrogen-abstraction reactions. However, the mechanisms behind these dissociations are dependent on the impinging plasma species, i.e. a clear difference is observed in the mechanisms upon impact of HO2 radicals and H2O2 molecules on one hand and OH radicals on the other hand. Our simulation results are in good agreement with experimental observations.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000350275400005 Publication Date 2014-09-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1612-8850; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.846 Times cited (down) 18 Open Access
Notes Approved Most recent IF: 2.846; 2015 IF: 2.453
Call Number c:irua:123540 Serial 1589
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Author Brault, P.; Neyts, E.C.
Title Molecular dynamics simulations of supported metal nanocatalyst formation by plasma sputtering Type A1 Journal article
Year 2015 Publication Catalysis today Abbreviated Journal Catal Today
Volume 256 Issue 256 Pages 3-12
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Magnetron sputtering is a widely used physical vapor deposition technique for deposition and formation of nanocatalyst thin films and clusters. Nevertheless, so far only few studies investigated this formation process at the fundamental level. We here review atomic scale molecular dynamics simulations aimed at elucidating the nanocatalyst growth process through magnetron sputtering. We first introduce the basic magnetron sputtering background and machinery of molecular dynamics simulations, and then describe the studies conducted in this field so far. We also present a perspective view on how the field may be developed further.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000360085300002 Publication Date 2015-02-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0920-5861; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.636 Times cited (down) 18 Open Access
Notes Approved Most recent IF: 4.636; 2015 IF: 3.893
Call Number c:irua:127408 Serial 2174
Permanent link to this record
 

 
Author Tang, X.; Reckinger, N.; Poncelet, O.; Louette, P.; Urena, F.; Idrissi, H.; Turner, S.; Cabosart, D.; Colomer, J.-F.; Raskin, J.-P.; Hackens, B.; Francis, L.A.
Title Damage evaluation in graphene underlying atomic layer deposition dielectrics Type A1 Journal article
Year 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 5 Issue 5 Pages 13523
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Based on micro-Raman spectroscopy (muRS) and X-ray photoelectron spectroscopy (XPS), we study the structural damage incurred in monolayer (1L) and few-layer (FL) graphene subjected to atomic-layer deposition of HfO2 and Al2O3 upon different oxygen plasma power levels. We evaluate the damage level and the influence of the HfO2 thickness on graphene. The results indicate that in the case of Al2O3/graphene, whether 1L or FL graphene is strongly damaged under our process conditions. For the case of HfO2/graphene, muRS analysis clearly shows that FL graphene is less disordered than 1L graphene. In addition, the damage levels in FL graphene decrease with the number of layers. Moreover, the FL graphene damage is inversely proportional to the thickness of HfO2 film. Particularly, the bottom layer of twisted bilayer (t-2L) has the salient features of 1L graphene. Therefore, FL graphene allows for controlling/limiting the degree of defect during the PE-ALD HfO2 of dielectrics and could be a good starting material for building field effect transistors, sensors, touch screens and solar cells. Besides, the formation of Hf-C bonds may favor growing high-quality and uniform-coverage dielectric. HfO2 could be a suitable high-K gate dielectric with a scaling capability down to sub-5-nm for graphene-based transistors.
Address ICTEAM Institute, Universite catholique de Louvain, Place du Levant 3, 1348 Louvain-la-Neuve, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000360147400001 Publication Date 2015-08-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited (down) 18 Open Access
Notes The authors thank the staff of UCL’s Winfab and Welcome for technical support. Xiaohui Tang is a senior research of UCL. This work is financially supported by the Multi-Sensor-Platform for Smart Building Management project (No. 611887) and the Action de Recherche Concertée (ARC) “StressTronics”, Communauté française de Belgique. Part of this work is financially supported by the Belgian Fund for Scientific Research (FRS-FNRS) under FRFC contract “Chemographene” (No. 2.4577.11). J.-F. Colomer and B. Hackens are Research Associates of FRS-FNRS. This research used resources of the Electron Microscopy Service located at the University of Namur (“Plateforme Technologique Morphologie – Imagerie”). This research used resources of the ELISE Service of the University of Namur. This Service is member of the “Plateforme Technologique SIAM”. The research leading to this work has received partial funding from the European Union Seventh Framework Program under grant agreement No 604391 Graphene Flagship. Approved Most recent IF: 4.259; 2015 IF: 5.578
Call Number c:irua:129193 Serial 3958
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Author Verlackt, C.C.W.; Neyts, E.C.; Jacob, T.; Fantauzzi, D.; Golkaram, M.; Shin, Y.-K.; van Duin, A.C.T.; Bogaerts, A.
Title Atomic-scale insight into the interactions between hydroxyl radicals and DNA in solution using the ReaxFF reactive force field Type A1 Journal article
Year 2015 Publication New journal of physics Abbreviated Journal New J Phys
Volume 17 Issue 17 Pages 103005
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Cold atmospheric pressure plasmas have proven to provide an alternative treatment of cancer by targeting tumorous cells while leaving their healthy counterparts unharmed. However, the underlying mechanisms of the plasma–cell interactions are not yet fully understood. Reactive oxygen species, and in particular hydroxyl radicals (OH), are known to play a crucial role in plasma driven apoptosis of

malignant cells. In this paper we investigate the interaction of OH radicals, as well as H2O2 molecules and HO2 radicals, with DNA by means of reactive molecular dynamics simulations using the ReaxFF force field. Our results provide atomic-scale insight into the dynamics of oxidative stress on DNA caused by the OH radicals, while H2O2 molecules appear not reactive within the considered timescale. Among the observed processes are the formation of 8-OH-adduct radicals, forming the first stages towards the formation of 8-oxoGua and 8-oxoAde, H-abstraction reactions of the amines, and the partial opening of loose DNA ends in aqueous solution.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000367328100001 Publication Date 2015-10-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.786 Times cited (down) 18 Open Access
Notes CCWV,ECN and AB acknowledge the contribution of J Van Beeck who is investigating the interaction between H2O2 andDNAusingrMDsimulations. Furthermore, they acknowledge financial support from the Fund for Scientific Research—Flanders (project number G012413N). The calculations were performed using the Turing HPCinfrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. TJ and DF gratefully acknowledge support from the European Research Council through the ERC-Starting GrantTHEOFUN(Grant Agreement No. 259608). Approved Most recent IF: 3.786; 2015 IF: 3.558
Call Number c:irua:129178 Serial 3955
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Author Deyneko, D.V.; Morozov, V.A.; Hadermann, J.; Savon, A.E.; Spassky, D.A.; Stefanovich, S.Y.; Belik, A.A.; Lazoryak, B.I.
Title A novel red Ca8.5Pb0.5Eu(PO4)7 phosphor for light emitting diodes application Type A1 Journal article
Year 2015 Publication Journal of alloys and compounds Abbreviated Journal J Alloy Compd
Volume 647 Issue 647 Pages 965-972
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Ca9-xPbxEu(PO4)(7) (0 <= x <= 1) solid solutions with a whitlockite-type (or beta-Ca-3(PO4)(2)-type) structure (sp.gr. R3c) were prepared by a standard solid-state method in air. Their luminescent properties under near-ultraviolet (n-UV) light were investigated. Excitation spectra of Ca9-xPbxEu(PO4)(7) showed the strongest absorption at about 395 nm, which matches well with commercially available n-UV-emitting GaN-based LED chips. Emission spectra indicated an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+, with a maximum in the intensity for Ca8.5Pb0.5Eu(PO4)(7). The emission intensity of Ca8.5Pb0.5Eu(PO4)(7) was about 1.8 times higher than that of a Ca9Eu(PO4)(7) phosphor. We suggest that the introduction of Pb2+ is an efficient approach to enhance luminescence properties of such phosphors. We clarified the influence of the Ca2+/Pb2+ substitution on intensities of three bands for the D-5(0) -> F-7(0) transition in excitation spectra of Ca9-xPbxEu(PO4)(7). In addition, we found a reversible first-order phase transition from R3c to R (3) over barc symmetry by second-harmonic generation in the range from 753 K (x = 1) to 846 K (x = 0). (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000361156400135 Publication Date 2015-06-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-8388 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.133 Times cited (down) 18 Open Access
Notes Approved Most recent IF: 3.133; 2015 IF: 2.999
Call Number UA @ lucian @ c:irua:128720 Serial 4215
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Author Forsh, E.A.; Abakumov, A.M.; Zaytsev, V.B.; Konstantinova, E.A.; Forsh, P.A.; Rumyantseva, M.N.; Gaskov, A.M.; Kashkarov, P.K.
Title Optical and photoelectrical properties of nanocrystalline indium oxide with small grains Type A1 Journal article
Year 2015 Publication Thin solid films : an international journal on the science and technology of thin and thick films Abbreviated Journal Thin Solid Films
Volume 595 Issue 595 Pages 25-31
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Optical properties, spectral dependence of photoconductivity and photoconductivity decay in nanocrystalline indium oxide In2O3 are studied. A number of nanostructured In2O3 samples with various nanocrystals size are prepared by sol-gel method and characterized using various techniques. The mean nanocrystals size varies from 7 to 8 nm to 39-41 nm depending on the preparation conditions. Structural characterization of the In2O3 samples is performed by means of transmission electron microscopy and X-ray powder diffraction. The combined analysis of ultraviolet-visible absorption spectroscopy and diffuse reflectance spectroscopy shows that nanostructuring leads to the change in optical band gap: optical band gap of the In2O3 samples (with an average nanocrystal size from 7 to 41 nm) is equal to 2.8 eV. We find out the correlation between spectral dependence of photoconductivity and optical properties of nanocrystalline In2O3: sharp increase in photoconductivity was observed to begin at 2.8 eV that is equal to the optical bandgap in the In2O3 samples, and reached its maximum at 3.2-3.3 eV. The combined analysis of the slow photoconductivity decay in air, vacuum and argon, that was accurately fitted by a stretched-exponential function, and electron paramagnetic resonance (EPR) measurements shows that the kinetics of photoconductivity decay is strongly depended on the presence of oxygen molecules in the ambient of In2O3 nanocrystals. There is the quantitative correlation between EPR and photoconductivity data. Based on the obtained data we propose the model clearing up the phenomenon of permanent photoconductivity decay in nanocrystalline In2O3. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000365812400005 Publication Date 2015-10-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0040-6090 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.879 Times cited (down) 18 Open Access
Notes Approved Most recent IF: 1.879; 2015 IF: 1.759
Call Number UA @ lucian @ c:irua:130254 Serial 4219
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