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Author Van Gompel, M.; Atalay, A.Y.; Gaulke, A.; Van Bael, M.K.; D'Haen, J.; Turner, S.; Van Tendeloo, G.; Vanacken, J.; Moshchalkov, V.V.; Wagner, P.
Title Morphological TEM studies and magnetoresistance analysis of sputtered Al-substituted ZnO films : the role of oxygen Type A1 Journal article
Year 2015 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A
Volume 212 Issue 212 Pages 1191-1201
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this article, we report on the synthesis of thin, epitaxial films of the transparent conductive oxide Al:ZnO on (0001)-oriented synthetic sapphire substrates by DC sputtering from targets with a nominal 1 at.% Al substitution. The deposition was carried out at an unusually low substrate temperature of only 250 °C in argonoxygen mixtures as well as in pure argon. The impact of the processgas composition on the morphology was analysed by transmission electron microscopy, revealing epitaxial growth in all the cases with a minor impact of the process parameters on the resulting grain sizes. The transport properties resistivity, Hall effect and magnetoresistance were studied in the range from 10 to 300 K in DC and pulsed magnetic fields up to 45 T. While the carrier density and mobility are widely temperature independent, we identified a low fieldlow temperature regime in which the magnetoresistance shows an anomalous, negative behaviour. At higher fields and temperatures, the magnetoresistance exhibits a more conventional, positive curvature with increasing field strength. As a possible explanation, we propose carrier scattering at localised magnetic trace impurities and magnetic correlations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000356706500003 Publication Date (up) 2015-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6300; ISBN Additional Links UA library record; WoS full record
Impact Factor 1.775 Times cited Open Access
Notes Methusalem project NANO; FWO; 246791 COUNTATOMS Approved Most recent IF: 1.775; 2015 IF: 1.616
Call Number c:irua:126732 Serial 2204
Permanent link to this record
 
 
Author Blandy, J.N.; Abakumov, A.M.; Christensen, K.E.; Hadermann, J.; Adamson, P.; Cassidy, S.J.; Ramos, S.; Free, D.G.; Cohen, H.; Woodruff, D.N.; Thompson, A.L.; Clarke, S.J.;
Title Soft chemical control of the crystal and magnetic structure of a layered mixed valent manganite oxide sulfide Type A1 Journal article
Year 2015 Publication APL materials Abbreviated Journal Apl Mater
Volume 3 Issue 3 Pages 041520
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Oxidative deintercalation of copper ions from the sulfide layers of the layered mixed-valent manganite oxide sulfide Sr2MnO2Cu1.5S2 results in control of the copper-vacancy modulated superstructure and the ordered arrangement of magnetic moments carried by the manganese ions. This soft chemistry enables control of the structures and properties of these complex materials which complement mixed-valent perovskite and perovskite-related transition metal oxides. (C) 2015 Author(s).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000353828400027 Publication Date (up) 2015-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2166-532X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.335 Times cited 5 Open Access
Notes Approved Most recent IF: 4.335; 2015 IF: NA
Call Number c:irua:126021 Serial 3049
Permanent link to this record
 
 
Author La Porta, A.; Sanchez-Iglesias, A.; Altantzis, T.; Bals, S.; Grzelczak, M.; Liz-Marzan, L.M.
Title Multifunctional self-assembled composite colloids and their application to SERS detection Type A1 Journal article
Year 2015 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 7 Issue 7 Pages 10377-10381
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We present a simple method for the co-encapsulation of gold nanostars and iron-oxide nanoparticles into hybrid colloidal composites that are highly responsive to both light and external magnetic fields. Self-assembly was driven by hydrophobic interactions between polystyrene capped gold nanostars and iron oxide nanocrystals stabilized with oleic acid, upon addition of water. A block copolymer was then used to encapsulate the resulting spherical colloidal particle clusters, which thereby became hydrophilic. Electron microscopy analysis unequivocally shows that each composite particle comprises a single Au nanostar surrounded by a few hundreds of iron oxide nanocrystals. We demonstrate that this hybrid colloidal system can be used as an efficient substrate for surface enhanced Raman scattering, using common dyes as model molecular probes. The co-encapsulation of iron oxide nanoparticles renders the system magnetically responsive, so that application of an external magnetic field leads to particle accumulation and limits of detection are in the nM range.
Address A1 Article; Electron microscopy for materials research (EMAT);
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000355987300010 Publication Date (up) 2015-04-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 51 Open Access OpenAccess
Notes 267867 Plasmaquo; 335078 Colouratom; 262348 Esmi; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 7.367; 2015 IF: 7.394
Call Number c:irua:127003 Serial 3940
Permanent link to this record
 
 
Author Milošević, M.V.; Perali, A.
Title Emergent phenomena in multicomponent superconductivity: an introduction to the focus issue Type A1 Journal article
Year 2015 Publication Superconductor Science & Technology Abbreviated Journal Supercond Sci Tech
Volume 28 Issue 28 Pages 060201
Keywords A1 Journal article; CMT
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000354110200001 Publication Date (up) 2015-04-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links
Impact Factor 2.878 Times cited 41 Open Access
Notes ; ; Approved Most recent IF: 2.878; 2015 IF: 2.325
Call Number UA @ lucian @ Serial 3945
Permanent link to this record
 
 
Author Hannibal, S.; Kettmann, P.; Croitoru, M.D.; Vagov, A.; Axt, V.M.; Kuhn, T.
Title Quench dynamics of an ultracold Fermi gas in the BCS regime : spectral properties and confinement-induced breakdown of the Higgs mode Type A1 Journal article
Year 2015 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
Volume 91 Issue 91 Pages 043630
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The Higgs amplitude mode of the order parameter of an ultracold confined Fermi gas in the BCS regime after a quench of the coupling constant is analyzed theoretically. A characteristic feature is a damped oscillation which at a certain transition time changes into a rather irregular dynamics. We compare the numerical solution of the full set of nonlinear equations of motion for the normal and anomalous Bogoliubov quasiparticle excitations with a linearized approximation. In doing so the transition time as well as the difference between resonant systems, i.e., systems where the Fermi energy is close to a sub-band minimum, and off-resonant systems can be well understood and traced back to the system and geometry parameters.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000353448500005 Publication Date (up) 2015-04-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1094-1622; 1050-2947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.925 Times cited 10 Open Access
Notes ; M.D.C. acknowledges support by the BELSPO Back to Belgium Grant. ; Approved Most recent IF: 2.925; 2015 IF: NA
Call Number UA @ lucian @ c:irua:132509 Serial 4235
Permanent link to this record
 
 
Author Van de Put, M.L.; Vandenberghe, W.G.; Magnus, W.; Sorée, B.
Title An envelope function formalism for lattice-matched heterostructures Type A1 Journal article
Year 2015 Publication Physica: B : condensed matter Abbreviated Journal Physica B
Volume 470-471 Issue 470-471 Pages 69-75
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The envelope function method traditionally employs a single basis set which, in practice, relates to a single material because the k.p matrix elements are generally only known in a particular basis. In this work, we defined a basis function transformation to alleviate this restriction. The transformation is completely described by the known inter-band momentum matrix elements. The resulting envelope function equation can solve the electronic structure in lattice matched heterostructures without resorting to boundary conditions at the interface between materials, while all unit-cell averaged observables can be calculated as with the standard envelope function formalism. In the case of two coupled bands, this heterostructure formalism is equivalent to the standard formalism while taking position dependent matrix elements. (C) 2015 Elsevier B.V. All rights reserved
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000355149600011 Publication Date (up) 2015-04-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.386 Times cited 5 Open Access
Notes ; ; Approved Most recent IF: 1.386; 2015 IF: 1.319
Call Number c:irua:126397 Serial 95
Permanent link to this record
 
 
Author Krause, F.F.; Ahl, J.P.; Tytko, D.; Choi, P.P.; Egoavil, R.; Schowalter, M.; Mehrtens, T.; Müller-Caspary, K.; Verbeeck, J.; Raabe, D.; Hertkorn, J.; Engl, K.; Rosenauer, A.
Title Homogeneity and composition of AlInGaN : a multiprobe nanostructure study Type A1 Journal article
Year 2015 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 156 Issue 156 Pages 29-36
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The electronic properties of quaternary AlInGaN devices significantly depend on the homogeneity of the alloy. The identification of compositional fluctuations or verification of random-alloy distribution is hence of grave importance. Here, a comprehensive multiprobe study of composition and compositional homogeneity is presented, investigating AlInGaN layers with indium concentrations ranging from 0 to 17 at% and aluminium concentrations between 0 and 39 at% employing high-angle annular dark field scanning electron microscopy (HAADF STEM), energy dispersive X-ray spectroscopy (EDX) and atom probe tomography (APT). EDX mappings reveal distributions of local concentrations which are in good agreement with random alloy atomic distributions. This was hence investigated with HAADF STEM by comparison with theoretical random alloy expectations using statistical tests. To validate the performance of these tests, HAADF STEM image simulations were carried out for the case of a random-alloy distribution of atoms and for the case of In-rich clusters with nanometer dimensions. The investigated samples, which were grown by metal-organic vapor phase epitaxy (MOVPE), were thereby found to be homogeneous on this nanometer scale. Analysis of reconstructions obtained from APT measurements yielded matching results. Though HAADF STEM only allows for the reduction of possible combinations of indium and aluminium concentrations to the proximity of isolines in the two-dimensional composition space. The observed ranges of composition are in good agreement with the EDX and APT results within the respective precisions.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000361001800006 Publication Date (up) 2015-04-26
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 11 Open Access
Notes 312483 Esteem2; esteem2_ta Approved Most recent IF: 2.843; 2015 IF: 2.436
Call Number c:irua:126965 c:irua:126965UA @ admin @ c:irua:126965 Serial 1485
Permanent link to this record
 
 
Author Chaves, A.; Low, T.; Avouris, P.; Çakir, D.; Peeters, F.M.
Title Anisotropic exciton Stark shift in black phosphorus Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 91 Issue 91 Pages 155311
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We calculate the excitonic spectrum of few-layer black phosphorus by direct diagonalization of the effective mass Hamiltonian in the presence of an applied in-plane electric field. The strong attractive interaction between electrons and holes in this system allows one to investigate the Stark effect up to very high ionizing fields, including also the excited states. Our results show that the band anisotropy in black phosphorus becomes evident in the direction-dependent field-induced polarizability of the exciton.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000353459200005 Publication Date (up) 2015-04-27
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 88 Open Access
Notes ; Discussions with J. M. Pereira Jr. and J. S. de Souza are gratefully acknowledged. This work was supported by the Brazilian Council for Research (CNPq) through the PQ and Science Without Borders programs, the Flemish Science Foundation (FWO-Vl), the Methusalem programme of the Flemish government, and the Bilateral program (CNPq-FWO) between Flanders and Brazil. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:132506 Serial 4141
Permanent link to this record
 
 
Author Lin, F.; Meng; Kukueva, E.; Altantzis, T.; Mertens, M.; Bals, S.; Cool, P.; Van Doorslaer, S.
Title Direct-synthesis method towards copper-containing periodic mesoporous organosilicas : detailed investigation of the copper distribution in the material Type A1 Journal article
Year 2015 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T
Volume 44 Issue 44 Pages 9970-9979
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract Three-dimensional cubic Fm (3) over barm mesoporous copper-containing ethane-bridged PMO materials have been prepared through a direct-synthesis method at room temperature in the presence of cetyltrimethylammonium bromide as surfactant. The obtained materials have been unambiguously characterized in detail by several sophisticated techniques, including XRD, UV-Vis-Dr, TEM, elemental mapping, continuous- wave and pulsed EPR spectroscopy. The results show that at lower copper loading, the Cu2+ species are well dispersed in the Cu-PMO materials, and mainly exist as mononuclear Cu2+ species. At higher copper loading amount, Cu2+ clusters are observed in the materials, but the distribution of the Cu2+ species is still much better in the Cu-PMO materials prepared through the direct-synthesis method than in a Cu-containing PMO material prepared through an impregnation method. Moreover, the evolution of the copper incorporation during the PMO synthesis has been followed by EPR. The results show that the immobilization of the Cu2+ ion/complex and the formation of the PMO materials are taking place simultaneously. The copper ions are found to be situated on the inner surface of the mesopores of the materials and are accessible, which will be beneficial for the catalytic applications.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000355000700028 Publication Date (up) 2015-04-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-9226;1477-9234; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited 11 Open Access OpenAccess
Notes Goa-Bof; 335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 4.029; 2015 IF: 4.197
Call Number c:irua:126422 Serial 725
Permanent link to this record
 
 
Author Iyikanat, F.; Sahin, H.; Senger, R.T.; Peeters, F.M.
Title Vacancy formation and oxidation characteristics of single layer TiS3 Type A1 Journal article
Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 119 Issue 119 Pages 10709-10715
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The structural, electronic, and magnetic properties of pristine, defective, and oxidized monolayer TiS3 are investigated using first-principles calculations in the framework of density functional theory. We found that a single layer of TiS3 is a direct band gap semiconductor, and the bonding nature of the crystal is fundamentally different from other transition metal chalcogenides. The negatively charged surfaces of single layer TiS3 makes this crystal a promising material for lubrication applications. The formation energies of possible vacancies, i.e. S, Ti, TiS, and double S, are investigated via total energy optimization calculations. We found that the formation of a single S vacancy was the most likely one among the considered vacancy types. While a single S vacancy results in a nonmagnetic, semiconducting character with an enhanced band gap, other vacancy types induce metallic behavior with spin polarization of 0.3-0.8 mu(B). The reactivity of pristine and defective TiS3 crystals against oxidation was investigated using conjugate gradient calculations where we considered the interaction with atomic O, O-2, and O-3. While O-2 has the lowest binding energy with 0.05-0.07 eV, O-3 forms strong bonds stable even at moderate temperatures. The strong interaction (3.9-4.0 eV) between atomic O and TiS3 results in dissociative adsorption of some O-containing molecules. In addition, the presence of S-vacancies enhances the reactivity of the surface with atomic O, whereas it had a negative effect on the reactivity with O-2 and O-3 molecules.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000354912200063 Publication Date (up) 2015-04-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 51 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 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. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. RI., H.S., and R.T.S. acknowledge the support from TUBITAK through project 114F397. ; Approved Most recent IF: 4.536; 2015 IF: 4.772
Call Number c:irua:126410 Serial 3829
Permanent link to this record
 
 
Author Lobato, I.; Van Dyck, D.
Title MULTEM : a new multislice program to perform accurate and fast electron diffraction and imaging simulations using graphics processing units with CUDA Type A1 Journal article
Year 2015 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 156 Issue 156 Pages 9-17
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract The main features and the GPU implementation of the MULTEM program are presented and described. This new program performs accurate and fast multislice simulations by including higher order expansion of the multislice solution of the high energy Schrodinger equation, the correct subslicing of the three-dimensional potential and top-bottom surfaces. The program implements different kinds of simulation for CTEM, STEM, ED, PED, CBED, ADF-TEM and ABF-HC with proper treatment of the spatial and temporal incoherences. The multislice approach described here treats the specimen as amorphous material which allows a straightforward implementation of the frozen phonon approximation. The generalized transmission function for each slice is calculated when is needed and then discarded. This allows us to perform large simulations that can include millions of atoms and keep the computer memory requirements to a reasonable level. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000361001800003 Publication Date (up) 2015-04-28
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 32 Open Access
Notes Approved Most recent IF: 2.843; 2015 IF: 2.436
Call Number UA @ lucian @ c:irua:127848 Serial 4209
Permanent link to this record
 
 
Author Papageorgiou, D.G.; Filippousi, M.; Pavlidou, E.; Chrissafis, K.; Van Tendeloo, G.; Bikiaris, D.
Title Effect of clay modification on structureproperty relationships and thermal degradation kinetics of \beta-polypropylene/clay composite materials Type A1 Journal article
Year 2015 Publication Journal of thermal analysis and calorimetry Abbreviated Journal J Therm Anal Calorim
Volume 122 Issue 122 Pages 393-406
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The influence of neat and organically modified montmorillonite on the structureproperty relationships of a β-nucleated polypropylene matrix has been thoroughly investigated. High-angle annular dark field scanning transmission electron microscopy revealed that the organic modification of clay facilitated the dispersion of the clay, while X-ray diffractograms showed the α-nucleating effect of the clays on the β-nucleated matrix. The results from tensile tests showed that the organic modification of MMT affected profoundly only the tensile strength at yield and at break. The effect of the organic modification of the clay on the thermal stability of the composites was finally evaluated by thermogravimetric analysis, where the samples filled with oMMT decomposed faster than the ones filled with neat MMT, due to the decomposition of the organic salts that were initially used for the modification of MMT. A kinetics study of the thermal degradation of the composites was also performed, in order to export additional conclusions on the activation energy of the samples.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos 000361431200042 Publication Date (up) 2015-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1388-6150;1588-2926; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.953 Times cited 7 Open Access
Notes 262348 Esmi Approved Most recent IF: 1.953; 2015 IF: 2.042
Call Number c:irua:127492 Serial 805
Permanent link to this record
 
 
Author Zeng, Y.-J.; Schouteden, K.; Amini, M.N.; Ruan, S.-C.; Lu, Y.-F.; Ye, Z.-Z.; Partoens, B.; Lamoen, D.; Van Haesendonck, C.
Title Electronic band structures and native point defects of ultrafine ZnO nanocrystals Type A1 Journal article
Year 2015 Publication ACS applied materials and interfaces Abbreviated Journal Acs Appl Mater Inter
Volume 7 Issue 7 Pages 10617-10622
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Ultrafine ZnO nanocrystals with a thickness down to 0.25 nm are grown by a metalorganic chemical vapor deposition method. Electronic band structures and native point defects of ZnO nanocrystals are studied by a combination of scanning tunneling microscopy/spectroscopy and first-principles density functional theory calculations. Below a critical thickness of nm ZnO adopts a graphitic-like structure and exhibits a wide band gap similar to its wurtzite counterpart. The hexagonal wurtzite structure, with a well-developed band gap evident from scanning tunneling spectroscopy, is established for a thickness starting from similar to 1.4 nm. With further increase of the thickness to 2 nm, V-O-V-Zn defect pairs are easily produced in ZnO nanocrystals due to the self-compensation effect in highly doped semiconductors.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000355055000063 Publication Date (up) 2015-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244;1944-8252; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.504 Times cited 15 Open Access
Notes Hercules; EWI Approved Most recent IF: 7.504; 2015 IF: 6.723
Call Number c:irua:126408 Serial 999
Permanent link to this record
 
 
Author McCalla, E.; Prakash, A.S.; Berg, E.; Saubanere, M.; Abakumov, A.M.; Foix, D.; Klobes, B.; Sougrati, M.T.; Rousse, G.; Lepoivre, F.; Mariyappan, S.; Doublet, M.L.; Gonbeau, D.; Novak, P.; Van Tendeloo, G.; Hermann, R.P.; Tarascon, J.M.;
Title Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials Type A1 Journal article
Year 2015 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
Volume 162 Issue 162 Pages A1341-A1351
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited Changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds, i.e. (O-2)(n-) species which on further delithiation show a spontaneous O-2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms. (C) 2015 The Electrochemical Society. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000355643700030 Publication Date (up) 2015-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4651;1945-7111; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.259 Times cited 23 Open Access
Notes Approved Most recent IF: 3.259; 2015 IF: 3.266
Call Number c:irua:126445 Serial 2903
Permanent link to this record
 
 
Author Delmelle, R.; Amin-Ahmadi, B.; Sinnaeve, M.; Idrissi, H.; Pardoen, T.; Schryvers, D.; Proost, J.
Title Effect of structural defects on the hydriding kinetics of nanocrystalline Pd thin films Type A1 Journal article
Year 2015 Publication International journal of hydrogen energy Abbreviated Journal Int J Hydrogen Energ
Volume 40 Issue 40 Pages 7335-7347
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract While the microstructure of a metal is well-known to affect its equilibrium hydrogen uptake and therefore the hydriding thermodynamics, microstructural effects on the hydriding kinetics are much less documented. Moreover, for thin film systems, such microstructural effects are difficult to separate from the internal stress effect, since most defects generate internal stresses. Such a decoupling has been achieved in this paper for nanocrystalline Pd thin film model systems through the use of a high-resolution, in-situ curvature measurement set-up during Pd deposition, annealing and hydriding. This set-up allowed producing Pd thin films with similar internal stress levels but significantly different microstructures. This was evidenced from detailed defect statistics obtained by transmission electron microscopy, which showed that the densities of grain boundaries, dislocations and twin boundaries have all been lowered by annealing. The same set-up was then used to study the hydriding equilibrium and kinetic behaviour of the resulting films at room temperature. A full quantitative analysis of their hydriding cycles showed that the rate constants of both the adsorption- and absorption-limited kinetic regimes were strongly affected by microstructure. Defect engineering was thereby shown to increase the rate constants for hydrogen adsorption and absorption in Pd by a factor 40 and 30, respectively. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000355884300012 Publication Date (up) 2015-05-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0360-3199; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.582 Times cited 13 Open Access
Notes Iap 7/21 Approved Most recent IF: 3.582; 2015 IF: 3.313
Call Number c:irua:126429 Serial 838
Permanent link to this record
 
 
Author Silva, F.S.; Godoi, R.H.M.; Tauler, R.; de André, P.A.; Saldiva, P.H.N.; Van Grieken, R.; de Marchi, M.R.R.
Title Elemental composition of PM2.5 in Araraquara City (Southeast Brazil) during seasons with and without sugar cane burning Type A2 Journal article
Year 2015 Publication Journal of environmental protection Abbreviated Journal
Volume 6 Issue 5 Pages 426-434
Keywords A2 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5), present in polluted air, has been associated with a large spectrum of health impairments, mainly because of its deep deposition into the lungs. Araraquara City (Southeast Brazil) is surrounded by sugar-cane plantations, which are burned to facilitate the harvesting; this process causes environmental pollution due to the large amounts of soot that are released into the atmosphere. In this work, the elemental composition of PM2.5 was studied in two scenarios, namely in sugar-cane harvesting (HV) and in non-harvesting (NHV) seasons. The sampling strategy included one campaign in each season. PM2.5 was collected using a dichotomous sampler (10 L·min-1, 24 h) with PTFE filters. Information concerning the bulk elemental concentration was provided by energy-dispersive X-ray fluorescence. Enrichment factor analysis indicated that S, Cl, K, Cr, Ni, Cu, Zn, As, Cd and Pb were highly enriched relative to their crustal ratios (to Al). Principal component analysis was used to get some insight about the sources of the elements. Principal component 1 (PC1) explained 30.5% of data variance. The elements that had high loading (>0.7) were: S, Cr, As, and Pb; these are associated with combustion of fossil fuels. In principal component 2 (PC2), Cl, Cu, Zn, and Cd showed high loadings; these elements are associated with biomass burning. The Ni concentration found is three times larger than the threshold of risk for lung cancer, as recommended by the World Health Organization.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date (up) 2015-05-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2152-2197 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:125885 Serial 7891
Permanent link to this record
 
 
Author Egoavil, R.; Huehn, S.; Jungbauer, M.; Gauquelin, N.; Béché, A.; Van Tendeloo, G.; Verbeeck; Moshnyaga, V.
Title Phase problem in the B-site ordering of La2CoMnO6 : impact on structure and magnetism Type A1 Journal article
Year 2015 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 7 Issue 7 Pages 9835-9843
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Epitaxial double perovskite La2CoMnO6 (LCMO) films were grown by metalorganic aerosol deposition on SrTiO3(111) substrates. A high Curie temperature, T-C = 226 K, and large magnetization close to saturation, M-S(5 K) = 5.8 mu(B)/f.u., indicate a 97% degree of B-site (Co,Mn) ordering within the film. The Co/Mn ordering was directly imaged at the atomic scale by scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (STEM-EDX). Local electron-energy-loss spectroscopy (EELS) measurements reveal that the B-sites are predominantly occupied by Co2+ and Mn4+ ions in quantitative agreement with magnetic data. Relatively small values of the (1/2 1/2 1/2) superstructure peak intensity, obtained by X-ray diffraction (XRD), point out the existence of ordered domains with an arbitrary phase relationship across the domain boundary. The size of these domains is estimated to be in the range 35-170 nm according to TEM observations and modelling the magnetization data. These observations provide important information towards the complexity of the cation ordering phenomenon and its implications on magnetism in double perovskites, and similar materials.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000354983100060 Publication Date (up) 2015-05-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 37 Open Access
Notes 312483 ESTEEM2; FWO G004413N; 246102 IFOX; Hercules; esteem2_jra3 Approved Most recent IF: 7.367; 2015 IF: 7.394
Call Number c:irua:126423 c:irua:126423 Serial 2586
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Author Wende, K.; Williams, P.; Dalluge, J.; Van Gaens, W.; Aboubakr, H.; Bischof, J.; von Woedtke, T.; Goyal, S.M.; Weltmann, K.D.; Bogaerts, A.; Masur, K.; Bruggeman, P.J.;
Title Identification of the biologically active liquid chemistry induced by a nonthermal atmospheric pressure plasma jet Type A1 Journal article
Year 2015 Publication Biointerphases Abbreviated Journal Biointerphases
Volume 10 Issue 10 Pages 029518
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The mechanism of interaction of cold nonequilibrium plasma jets with mammalian cells in physiologic liquid is reported. The major biological active species produced by an argon RF plasma jet responsible for cell viability reduction are analyzed by experimental results obtained through physical, biological, and chemical diagnostics. This is complemented with chemical kinetics modeling of the plasma source to assess the dominant reactive gas phase species. Different plasma chemistries are obtained by changing the feed gas composition of the cold argon based RF plasma jet from argon, humidified argon (0.27%), to argon/oxygen (1%) and argon/air (1%) at constant power. A minimal consensus physiologic liquid was used, providing isotonic and isohydric conditions and nutrients but is devoid of scavengers or serum constituents. While argon and humidified argon plasma led to the creation of hydrogen peroxide dominated action on the mammalian cells, argonoxygen and argonair plasma created a very different biological action and was characterized by trace amounts of hydrogen peroxide only. In particular, for the argonoxygen (1%), the authors observed a strong negative effect on mammalian cell proliferation and metabolism. This effect was distance dependent and showed a half life time of 30 min in a scavenger free physiologic buffer. Neither catalase and mannitol nor superoxide dismutase could rescue the cell proliferation rate. The strong distance dependency of the effect as well as the low water solubility rules out a major role for ozone and singlet oxygen but suggests a dominant role of atomic oxygen. Experimental results suggest that O reacts with chloride, yielding Cl2 − or ClO−. These chlorine species have a limited lifetime under physiologic conditions and therefore show a strong time dependent biological activity. The outcomes are compared with an argon MHz plasma jet (kinpen) to assess the differences between these (at least seemingly) similar plasma sources.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000357195600036 Publication Date (up) 2015-05-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1934-8630;1559-4106; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.603 Times cited 137 Open Access
Notes Approved Most recent IF: 2.603; 2015 IF: 3.374
Call Number c:irua:126774 Serial 1549
Permanent link to this record
 
 
Author Kato, T.; Neyts, E.C.; Abiko, Y.; Akama, T.; Hatakeyama, R.; Kaneko, T.
Title Kinetics of energy selective Cs encapsulation in single-walled carbon nanotubes for damage-free and position-selective doping Type A1 Journal article
Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 119 Issue 119 Pages 11903-11908
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A method has been developed for damage-free cesium (Cs) encapsulation within single-walled carbon nanotubes (SWNTs) with fine position selectivity. Precise energy tuning of Cs-ion irradiation revealed that there is a clear energy window (2060 eV) for the efficient encapsulation of Cs through the hexagonal network of SWNT sidewalls without causing significant damage. This minimum energy threshold of Cs-ion encapsulation (∼20 eV) matches well with the value obtained by ab initio simulation (∼22 eV). Furthermore, position-selective Cs encapsulation was carried out, resulting in the successful formation of pn-junction SWNT thin films with excellent environmental stability.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000355495600072 Publication Date (up) 2015-05-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 3 Open Access
Notes Approved Most recent IF: 4.536; 2015 IF: 4.772
Call Number c:irua:125928 Serial 1760
Permanent link to this record
 
 
Author Li, L.L.; Xu, W.; Peeters, F.M.
Title Optical conductivity of topological insulator thin films Type A1 Journal article
Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 117 Issue 117 Pages 175305
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a detailed theoretical study on the optoelectronic properties of topological insulator thin film (TITFs). The k . p approach is employed to calculate the energy spectra and wave functions for both the bulk and surface states in the TITF. With these obtained results, the optical conductivities induced by different electronic transitions among the bulk and surface states are evaluated using the energy-balance equation derived from the Boltzmann equation. We find that for Bi2Se3-based TITFs, three characteristic regimes for the optical absorption can be observed. (i) In the low radiation frequency regime (photon energy (h) over bar omega < 200 meV), the free-carrier absorption takes place due to intraband electronic transitions. An optical absorption window can be observed. (ii) In the intermediate radiation frequency regime (200 < (h) over bar omega < 300 meV), the optical absorption is induced mainly by interband electronic transitions from surface states in the valance band to surface states in the conduction band and an universal value sigma(0) = e(2) / (8<(h)over bar>) for the optical conductivity can be obtained. (iii) In the high radiation frequency regime ((h) over bar omega > 300 meV), the optical absorption can be achieved via interband electronic transitions from bulk and surface states in the valance band to bulk and surface states in the conduction band. A strong absorption peak can be observed. These interesting findings indicate that optical measurements can be applied to identify the energy regimes of bulk and surface states in the TITF. (C) 2015 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000354984100615 Publication Date (up) 2015-05-06
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 9 Open Access
Notes ; This work was supported by the National Natural Science Foundation of China (Grant No. 11304316), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; Approved Most recent IF: 2.068; 2015 IF: 2.183
Call Number c:irua:126412 Serial 2473
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Author van Aarle, W.; Palenstijn, W.J.; De Beenhouwer, J.; Altantzis, T.; Bals, S.; Batenburg, K.J.; Sijbers, J.
Title The ASTRA Toolbox: A platform for advanced algorithm development in electron tomography Type A1 Journal article
Year 2015 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 157 Issue 157 Pages 35-47
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract We present the ASTRA Toolbox as an open platform for 3D image reconstruction in tomography. Most of the software tools that are currently used in electron tomography offer limited flexibility with respect to the geometrical parameters of the acquisition model and the algorithms used for reconstruction. The ASTRA Toolbox provides an extensive set of fast and flexible building blocks that can be used to develop advanced reconstruction algorithms, effectively removing these limitations. We demonstrate this flexibility, the resulting reconstruction quality, and the computational efficiency of this toolbox by a series of experiments, based on experimental dual-axis tilt series.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000361002400005 Publication Date (up) 2015-05-06
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 562 Open Access OpenAccess
Notes The authors acknowledge financial support from the iMinds ICONMetroCT project,the IWT SBO Tom Food project and from the Netherlands Organisation for Scientific Research (NWO),Project no. 639.072.005. Networking support was provided by the EXTREMA COST Action MP 1207. Sara Bals acknowledges financial support from the European Research Council (ERC Starting Grant #335078 COLOURATOMS).; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); Approved Most recent IF: 2.843; 2015 IF: 2.436
Call Number c:irua:127834 Serial 3974
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Author Akamine, H.; Van den Bos, K.H.W.; Gauquelin, N.; Farjami, S.; Van Aert, S.; Schryvers, D.; Nishida, M.
Title Determination of the atomic width of an APB in ordered CoPt using quantified HAADF-STEM Type A1 Journal article
Year 2015 Publication Journal of alloys and compounds Abbreviated Journal J Alloy Compd
Volume 644 Issue 644 Pages 570-574
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Anti-phase boundaries (APBs) in an ordered CoPt alloy are planar defects which disturb the ordered structure in their vicinity and decrease the magnetic properties. However, it has not yet been clarified to what extend the APBs disturb the ordering. In this study, high-resolution HAADF-STEM images are statistically analysed based on the image intensities estimated by the statistical parameter estimation theory. In the procedure, averaging intensities, fitting the intensity profiles to specific functions, and assessment based on a statistical test are performed. As a result, the APBs in the stable CoPt are found to be characterised by two atomic planes, and a contrast transition range as well as the centre of an inclined APB is determined. These results show that the APBs are quite sharp and therefore may have no notable effect on the net magnetic properties due to their small volume fraction. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000357143900083 Publication Date (up) 2015-05-07
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 12 Open Access
Notes FWO G036815N; G036915N; G037413N; 278510 VORTEX; Hercules; ECASJO_; Approved Most recent IF: 3.133; 2015 IF: 2.999
Call Number c:irua:127008 c:irua:127008 Serial 675
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Author Odin, G.P.; Vanmeert, F.; Farges, F.; Gand, G.; Janssens, K.; Romero-Sarmiento, M.-F.; Steyer, J.S.; Vantelon, D.; Rouchon, V.
Title Alteration of fossil-bearing shale (Autun, France; Permian), part II : monitoring artificial and natural ageing by combined use of S and Ca K-edge XANES analysis, Rock-Eval pyrolysis and FTIR analysis Type A1 Journal article
Year 2015 Publication Annales de paléontologie Abbreviated Journal Ann Paleontol
Volume 101 Issue 3 Pages 225-239
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Fossil-bearing shale specimens that include sulfides in their compositions are chemically reactive and sometimes also mechanically fragile. This decay is often related to iron sulfate efflorescence resulting from the oxidation of sulfide compounds. The processes underlying these degradations are poorly known, thus impeding the elaboration of curative or preventive treatments. The present contribution aims to identify the origin of museum specimen alterations. It focuses on the Flouest collection housed at the Museum National d'Histoire Naturelle (MNHN, Paris, France) and originating from the Autun Basin (Saone-et-Loire, France, Permian). To evaluate the alteration of MNHN specimens, it appeared necessary to compare their composition with that of unaltered shale so as to identify chemical changes occurring during ageing. Therefore, new material was collected in the Autun Basin, among others on the locality of Muse that corresponds to the same lithostratigraphic unit as that of the MNHN specimens. This material was, if necessary, artificially aged. The first part of this work, presented elsewhere, deals with the use of Xray diffraction and Mossbauer spectroscopy for characterizing iron reactivity and speciation. It leads to the conclusion that the reactivity of iron in the shale matrix was limited and could not account for the large efflorescence of iron (II) sulfate occurring nearby the fossil. The second part presented here focuses on the use of S K-edge X-ray Absorption Near Edge Structure (XANES) spectroscopy for characterizing sulfur speciation and reactivity. Measurements were performed on the shale matrix and on thin layers of maceral found in the proximity of damaged areas. As sulfur may be found in association with calcium or organic matter, complementary techniques were implemented, such as FTIR spectroscopy, Rock-Eval pyrolysis (characterization of organic matter content) and Ca K-edge XANES (analysis of calcium speciation) spectroscopy. It was shown that sulfur is mainly related to thioether, sulfoxide, iron sulfide, and sulfates whereas calcium is mainly bound to carboxylate, carbonate and/or sulfate groups. FTIR analysis of the macerals confirmed the presence of vitrinite on damaged MNHN specimens. The low oxygen content of new shale samples determined by Rock-Eval pyrolysis indicates that the organic matter is well preserved, despite the fact that samples come from outcrop surface. In the newly collected material, sulfur is mainly related to organic sulfides (thioether) with a minor occurrence of iron sulfide. In the shale fraction of damaged MNHN specimens, sulfur is mostly oxidized into a mixture of iron and calcium sulfate. However, in the vitrinite layers of the same specimens, a large proportion of sulfur corresponds to organic sulfides. Also the oxidation of sulfur does not occur homogeneously but preferentially in the shale fraction, probably because this latter is porous whereas vitrinite is not. Artificial ageing of new shale material showed that the oxidation of organic sulfides could be reproduced at 90 degrees C, 80% of relative humidity. However, the obtained efflorescence almost exclusively corresponds to calcium sulfate whereas iron (II) sulfates are mostly observed on MNHN specimens. The new material collected on site is probably to be questioned, and future studies will have to select new samples with fossil remains. This will be the object of the third part of this work. (C) 2015 Elsevier Masson SAS. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000363821700009 Publication Date (up) 2015-05-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0753-3969 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.113 Times cited 6 Open Access
Notes ; This work was conducted within a PhD work that was supported by a doctoral school grant of the Museum national d'Histoire naturelle, Paris, France. We acknowledge SOLEIL for provision of synchrotron radiation facilities (Proposals ID “20130462” and “20110189”) and we would like to thank Nicolas Trcera, Pierre Lagarde and Anne Marie Flanck for assistance in using beamline LUCIA. ; Approved Most recent IF: 1.113; 2015 IF: 0.970
Call Number UA @ admin @ c:irua:129523 Serial 5462
Permanent link to this record
 
 
Author Torun, E.; Sahin, H.; Singh, S.K.; Peeters, F.M.
Title Stable half-metallic monolayers of FeCl2 Type A1 Journal article
Year 2015 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 106 Issue 106 Pages 192404
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The structural, electronic, and magnetic properties of single layers of Iron Dichloride (FeCl2) were calculated using first principles calculations. We found that the 1T phase of the single layer FeCl2 is 0.17 eV/unit cell more favorable than its 1H phase. The structural stability is confirmed by phonon calculations. We found that 1T-FeCl2 possess three Raman-active (130, 179, and 237 cm(-1)) and one infrared-active (279 cm(-1)) phonon branches. The electronic band dispersion of the 1T-FeCl2 is calculated using both gradient approximation of Perdew-Burke-Ernzerhof and DFT-HSE06 functionals. Both functionals reveal that the 1T-FeCl2 has a half-metallic ground state with a Curie temperature of 17 K. (C) 2015 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000355008100020 Publication Date (up) 2015-05-13
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 84 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 ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. ; Approved Most recent IF: 3.411; 2015 IF: 3.302
Call Number c:irua:126411 Serial 3143
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Author Heijkers, S.; Snoeckx, R.; Kozák, T.; Silva, T.; Godfroid, T.; Britun, N.; Snyders, R.; Bogaerts, A.
Title CO2 conversion in a microwave plasma reactor in the presence of N2 : elucidating the role of vibrational levels Type A1 Journal article
Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 119 Issue 119 Pages 12815-12828
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A chemical kinetics model is developed for a CO2/N2 microwave plasma, focusing especially on the vibrational levels of both CO2 and N2. The model is used to calculate the CO2 and N2 conversion as well as the energy efficiency of CO2 conversion for different power densities and for N2 fractions in the CO2/N2 gas mixture ranging from 0 to 90%. The calculation results are compared with measurements, and agreements within 23% and 33% are generally found for the CO2 conversion and N2 conversion, respectively. To explain the observed trends, the destruction and formation processes of both CO2 and N2 are analyzed, as well as the vibrational distribution functions of both CO2 and N2. The results indicate that N2 contributes in populating the lower asymmetric levels of CO2, leading to a higher absolute CO2 conversion upon increasing N2 fraction. However, the effective CO2 conversion drops because there is less CO2 initially present in the gas mixture; thus, the energy efficiency also drops with rising N2 fraction.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000356317500005 Publication Date (up) 2015-05-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 56 Open Access
Notes Approved Most recent IF: 4.536; 2015 IF: 4.772
Call Number c:irua:126325 Serial 3523
Permanent link to this record
 
 
Author Pinera, I.; Cruz, C.M.; Abreu, Y.; Leyva, A.; van Espen, P.; Diaz, A.; Cabal, A.E.; Van Remortel, N.
Title Gamma induced atom displacements in LYSO and LuYAP crystals as used in medical imaging applications Type A1 Journal article
Year 2015 Publication Interactions With Materials And Atoms Abbreviated Journal
Volume 356 Issue Pages 46-52
Keywords A1 Journal article; Engineering sciences. Technology; Particle Physics Group; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The radiation damage, in terms of atom displacements, induced by gamma irradiation in LYSO and LuYAP crystals is presented. Sc-44, Na-22 and V-48 are used as gamma sources for this study. The energy of gammas from the electron positron annihilation processes (511 keV) is also included in the study. The atom displacements distributions inside each material are calculated following the Monte Carlo assisted Classical Method introduced by the authors. This procedure also allows to study the atom displacements in-depth distributions inside each crystal. The atom displacements damage in LYSO crystals is found to be higher than in LuYAP crystals, mainly provoked by the displacements of silicon and oxygen atoms. But the difference between atom displacements produced in LYSO and LuYAP decreases when more energetic sources are used. On the other hand, the correlation between the atom displacements and energy deposition in-depth distributions is excellent. The atom displacements to energy deposition ratio is found to increases with more energetic photon sources. LYSO crystals are then more liable to the atom displacements damage than LuYAP crystals. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000356990400008 Publication Date (up) 2015-05-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-583x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:127012 Serial 7987
Permanent link to this record
 
 
Author van Oeffelen, L.; Van Roy, W.; Idrissi, H.; Charlier, D.; Lagae, L.; Borghs, G.
Title Ion current rectification, limiting and overlimiting conductances in nanopores Type A1 Journal article
Year 2015 Publication PLoS ONE Abbreviated Journal Plos One
Volume 10 Issue 10 Pages e0124171
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Previous reports on Poisson-Nernst-Planck (PNP) simulations of solid-state nanopores have focused on steady state behaviour under simplified boundary conditions. These are Neumann boundary conditions for the voltage at the pore walls, and in some cases also Donnan equilibrium boundary conditions for concentrations and voltages at both entrances of the nanopore. In this paper, we report time-dependent and steady state PNP simulations under less restrictive boundary conditions, including Neumann boundary conditions applied throughout the membrane relatively far away from the nanopore. We simulated ion currents through cylindrical and conical nanopores with several surface charge configurations, studying the spatial and temporal dependence of the currents contributed by each ion species. This revealed that, due to slow co-diffusion of oppositely charged ions, steady state is generally not reached in simulations or in practice. Furthermore, it is shown that ion concentration polarization is responsible for the observed limiting conductances and ion current rectification in nanopores with asymmetric surface charges or shapes. Hence, after more than a decade of collective research attempting to understand the nature of ion current rectification in solid-state nanopores, a relatively intuitive model is retrieved. Moreover, we measured and simulated current-voltage characteristics of rectifying silicon nitride nanopores presenting overlimiting conductances. The similarity between measurement and simulation shows that overlimiting conductances can result from the increased conductance of the electric double-layer at the membrane surface at the depletion side due to voltage-induced polarization charges.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000354916100012 Publication Date (up) 2015-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-6203; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.806 Times cited 11 Open Access
Notes Approved Most recent IF: 2.806; 2015 IF: 3.234
Call Number c:irua:126366 Serial 1744
Permanent link to this record
 
 
Author Benito, P.; Nuyts, G.; Monti, M.; de Nolf, W.; Fornasari, G.; Janssens, K.; Scavetta, E.; Vaccari, A.
Title Stable Rh particles in hydrotalcite-derived catalysts coated on FeCrAlloy foams by electrosynthesis Type A1 Journal article
Year 2015 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ
Volume 179 Issue Pages 321-332
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Rh-based structured catalysts for the Catalytic Partial Oxidation of CH4 to syngas were prepared by electrosynthesis of Rh/Mg/Al hydrotalcite-type compounds on FeCrAlloy foams and calcination. The effects of Rh content, total metal concentration, and partial replacement of Mg2+ by Ni2+ in the electrolytic solution on coating thickness, Rh speciation, metallic particle size, and catalytic activity were investigated by SEM/EDS, mu-XRF/XANES and tests under diluted and concentrated reaction conditions. The amount of Rh species, present as Mg (RhxAl1-x)(2)O-4, depended on the thickness of the electrosynthesised layer as well as the Rh particle size and dispersion. Smaller and more dispersed particles were obtained by decreasing the Rh concentration in the electrolytic solution from Rh/Mg/Al=11/70/19 to 5/70/25 and 2/70/28 atomic ratio% (a.r.%) and in thinner rather than thicker layers. Despite the improvement in metallic particles features, the CH4 conversion was negatively affected by the low amount of active sites in the coating, the high metal support interaction and possibly the oxidation of metallic particles and carbon formation. A larger amount of solid containing well dispersed Rh particles was deposited by increasing the total metal concentration from 0.03 M to 0.06 M with the Rh/Mg/Al=5/70/25 a.r.%, and the catalytic performances were enhanced. The partial replacement of Mg2+ by Ni2+ gave rise to a very active bimetallic Rh/Ni catalyst, CH4 conversion and selectivity to syngas were above 90%, however, it slightly deactivated with time-on-stream. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000359873800036 Publication Date (up) 2015-05-19
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 14 Open Access
Notes ; The Authors acknowledge M. Salome for helping during the mu XRF/XANES experiments at ID21 Beamline of the ESRF, the Department of Structural Characterisation of CNR-IMM of Bologna for the access to the FEG-SEM facility and Dr F. Ospitali for the scientific support. Thanks are due to Farrel Lytle database for providing the necessary Rh metal spectrum (rhfoil.a99 in http:// ixs.iit.edu/data/FarrelLytledata/). The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, Italy) and the University of Bologna (FARB program) is gratefully acknowledged. ; Approved Most recent IF: 9.446; 2015 IF: 7.435
Call Number UA @ admin @ c:irua:127777 Serial 5846
Permanent link to this record
 
 
Author Borhani, A.H.; Berghmans, H.; Trashin, S.; De Wael, K.; Fago, A.; Moens, L.; Habibi-Rezaei, M.; Dewilde, S.
Title Kinetic properties and heme pocket structure of two domains of the polymeric hemoglobin of Artemia in comparison with the native molecule Type A1 Journal article
Year 2015 Publication Biochimica et biophysica acta : proteins and proteomics Abbreviated Journal Bba-Proteins Proteom
Volume 1854 Issue 10a Pages 1307-1316
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this project, we studied some physicochemical properties of two different globin domains of the polymeric hemoglobin of the brine shrimp Artemia salina and compared them with those of the native molecule. Two domains (AsHbC1D1 and AsHbC1D5) were cloned and expressed in BL21(DE3)pLysS strain of Escherichiacoli. The recombinant proteins as well as the native hemoglobin (AfHb) were purified from bacteria and frozen Artemia, respectively by standard chromatographic methods and assessed by SDS-PAGE. The heme environment of these proteins was studied by optical spectroscopy and ligand-binding kinetics (e.g. CO association and O2 binding affinity) were measured for the two recombinant proteins and the native hemoglobin. This indicates that the CO association rate for AsHbC1D1 is higher than that of AsHbC1D5 and AfHb, while the calculated P50 value for AsHbC1D1 is lower than that of AsHbC1D5 and AfHb. The geminate and bimolecular rebinding parameters indicate a significant difference between both domains. Moreover, EPR results showed that the heme pocket in AfHb is in a more closed conformation than the heme pocket in myoglobin. Finally, the reduction potential of − 0.13 V versus the standard hydrogen electrode was determined for AfHb by direct electrochemical measurements. It is about 0.06 V higher than the potential of the single domain AsHbC1D5. This work shows that each domain in the hemoglobin of Artemia has different characteristics of ligand binding.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000362307500008 Publication Date (up) 2015-05-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1570-9639 ISBN Additional Links UA library record; WoS full record
Impact Factor 2.773 Times cited Open Access
Notes ; This work was supported by the general grant for visiting scholar of the Ministry of Science, Research and Technology of I. R. Iran and by the University of Antwerp. ; Approved Most recent IF: 2.773; 2015 IF: 2.747
Call Number UA @ admin @ c:irua:125909 Serial 5683
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Author Becker, T.; Nelissen, K.; Cleuren, B.
Title Current fluctuations in boundary driven diffusive systems in different dimensions : a numerical study Type A1 Journal article
Year 2015 Publication New journal of physics Abbreviated Journal New J Phys
Volume 17 Issue 17 Pages 055023
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We use kinetic Monte Carlo simulations to investigate current fluctuations in boundary driven generalized exclusion processes, in different dimensions. Simulation results are in full agreement with predictions based on the additivity principle and the macroscopic fluctuation theory. The current statistics are independent of the shape of the contacts with the reservoirs, provided they are macroscopic in size. In general, the current distribution depends on the spatial dimension. For the special cases of the symmetric simple exclusion process and the zero-range process, the current statistics are the same for all spatial dimensions.
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Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000355282700001 Publication Date (up) 2015-05-27
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 5 Open Access
Notes ; We thank Christian Van den Broeck for bringing this problem to our attention. We are grateful to Bart Partoens and Carlo Vanderzande for a careful reading of the manuscript. This work was supported by the Flemish Science Foundation (Fonds Wetenschappelijk Onderzoek), Project No. G038811N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; Approved Most recent IF: 3.786; 2015 IF: 3.558
Call Number c:irua:126405 Serial 592
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