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Author Carvalho, J.C.N.; Nelissen, K.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M.
Title Diffusion in a quasi-one-dimensional system on a periodic substrate Type A1 Journal article
Year 2012 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 85 Issue 2:1 Pages 021136-021136,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The diffusion of charged particles interacting through a repulsive Yukawa potential, exp(-r/lambda)/r, confined by a parabolic potential in the y direction and subjected to a periodic substrate potential in the x direction is investigated. Langevin dynamic simulations are used to investigate the effect of the particle density, the amplitude of the periodic substrate, and the range of the interparticle interaction potential on the diffusive behavior of the particles. We found that in general the diffusion is suppressed with increasing the amplitude of the periodic potential, but for specific values of the strength of the substrate potential a remarkable increase of the diffusion is found with increasing the periodic potential amplitude. In addition, we found a strong dependence of the diffusion on the specific arrangement of the particles, e. g., single-chain versus multichain configuration. For certain particle configurations, a reentrant behavior of the diffusion is found as a function of the substrate strength due to structural transitions in the ordering of the particles.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos (up) 000300671500007 Publication Date 2012-02-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 9 Open Access
Notes ; This work was supported by the Brazilian agencies CNPq and FUNCAP (PRONEX-Grant), the Flemish Science Foundation (FWO-Vl), and the bilateral projects between Flanders and Brazil and the Flemish Science Foundation (FWO-VI) and CNPq. ; Approved Most recent IF: 2.366; 2012 IF: 2.313
Call Number UA @ lucian @ c:irua:97203 Serial 698
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Author Brück, S.; Paul, M.; Tian, H.; Müller, A.; Kufer, D.; Praetorius, C.; Fauth, K.; Audehm, P.; Goering, E.; Verbeeck, J.; Van Tendeloo, G.; Sing, M.; Claessen, R.;
Title Magnetic and electronic properties of the interface between half metallic Fe3O4 and semiconducting ZnO Type A1 Journal article
Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 100 Issue 8 Pages 081603-081603,4
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We have investigated the magnetic depth profile of an epitaxial Fe3O4 thin film grown directly on a semiconducting ZnO substrate by soft x-ray resonant magnetic reflectometry (XRMR) and electron energy loss spectroscopy (EELS). Consistent chemical profiles at the interface between ZnO and Fe3O4 are found from both methods. Valence selective EELS and XRMR reveal independently that the first monolayer of Fe at the interface between ZnO and Fe3O4 contains only Fe3+ ions. Besides this narrow 2.5 Å interface layer, Fe3O4 shows magnetic bulk properties throughout the whole film making highly efficient spin injection in this system feasible.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000300711200014 Publication Date 2012-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 12 Open Access
Notes The authors thank E. Pellegrin for helpful comments and S. Macke for help with the software REMAGX. S.B. acknowledges financial support by the HZB, Berlin, and the Australian Government via Grant No. RM08550. H.T. acknowledges funding from GOA project “XANES meets ELNES,” J.V. and G.V.T. acknowledge funding from the European Research Council under Grant No. 46791-COUN-TATOMS. The authors acknowledge financial support by the DFG through Forschergruppe FOR 1162. Approved Most recent IF: 3.411; 2012 IF: 3.794
Call Number UA @ lucian @ c:irua:95041UA @ admin @ c:irua:95041 Serial 1860
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Author Krstajić, P.M.; Peeters, F.M.
Title Remote electron plasmon polaron in graphene Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 8 Pages 085436-085436,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The Coulomb interaction and the correlation of a remote electron with a single layer of graphene is investigated in the presence of a magnetic field applied perpendicular to the graphene layer. The remote electron polarizes the electron gas in the graphene layer, which we describe in terms of excitations of virtual plasmons in graphene. The composite quasiparticle formed by electron plus polarization is called a plasmon polaron. The ground-state energy of this quasiparticle is calculated within perturbation theory for remote electrons in different environments.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000300831900012 Publication Date 2012-02-27
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 4 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:97202 Serial 2869
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Author Fang, C.M.; van Huis, M.A.; Thijsse, B.J.; Zandbergen, H.W.
Title Stability and crystal structures of iron carbides : a comparison between the semi-empirical modified embedded atom method and quantum-mechanical DFT calculations Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 5 Pages 054116-054116,7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Iron carbides play a crucial role in steel manufacturing and processing and to a large extent determine the physical properties of steel products. The modified embedded atom method (MEAM) in combination with Lee's Fe-C potential is a good candidate for molecular dynamics simulations on larger Fe-C systems. Here, we investigate the stability and crystal structures of pure iron and binary iron carbides using MEAM and compare them with the experimental data and quantum-mechanical density functional theory calculations. The analysis shows that the Fe-C potential gives reasonable results for the relative stability of iron and iron carbides. The performance of MEAM for the prediction of the potential energy and the calculated lattice parameters at elevated temperature for pure iron phases and cementite are investigated as well. The conclusion is that Lee's MEAM Fe-C potential provides a promising basis for further molecular dynamics simulations of Fe-C alloys and steels at lower temperatures (up to 800 K).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000300931900004 Publication Date 2012-02-29
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 18 Open Access
Notes Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:97201 Serial 3117
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Author Neyts, E.C.; van Duin, A.C.T.; Bogaerts, A.
Title Insights in the plasma-assisted growth of carbon nanotubes through atomic scale simulations : effect of electric field Type A1 Journal article
Year 2012 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 134 Issue 2 Pages 1256-1260
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Carbon nanotubes (CNTs) are nowadays routinely grown in a thermal CVD setup. State-of-the-art plasma-enhanced CVD (PECVD) growth, however, offers advantages over thermal CVD. A lower growth temperature and the growth of aligned freestanding single-walled CNTs (SWNTs) makes the technique very attractive. The atomic scale growth mechanisms of PECVD CNT growth, however, remain currently entirely unexplored. In this contribution, we employed molecular dynamics simulations to focus on the effect of applying an electric field on the SWNT growth process, as one of the effects coming into play in PECVD. Using sufficiently strong fields results in (a) alignment of the growing SWNTs, (b) a better ordering of the carbon network, and (c) a higher growth rate relative to thermal growth rate. We suggest that these effects are due to the small charge transfer occurring in the Ni/C system. These simulations constitute the first study of PECVD growth of SWNTs on the atomic level.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000301084300086 Publication Date 2011-11-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7863;1520-5126; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.858 Times cited 56 Open Access
Notes Approved Most recent IF: 13.858; 2012 IF: 10.677
Call Number UA @ lucian @ c:irua:97163 Serial 1673
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Author Verberck, B.; Partoens, B.; Peeters, F.M.; Trauzettel, B.
Title Strain-induced band gaps in bilayer graphene Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 12 Pages 125403-125403,10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a tight-binding investigation of strained bilayer graphene within linear elasticity theory, focusing on the different environments experienced by the A and B carbon atoms of the different sublattices. We find that the inequivalence of the A and B atoms is enhanced by the application of perpendicular strain epsilon(zz), which provides a physical mechanism for opening a band gap, most effectively obtained when pulling the two graphene layers apart. In addition, perpendicular strain introduces electron-hole asymmetry and can result in linear electronic dispersion near the K point. Our findings suggest experimental means for strain-engineered band gaps in bilayer graphene.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301113200005 Publication Date 2012-03-06
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 53 Open Access
Notes ; The authors would like to acknowledge O. Leenaerts, E. Mariani, K. H. Michel, and J. Schelter for useful discussions. B. V. was financially supported by the Flemish Science Foundation (FWO-Vl). This work was financially supported by the ESF program EuroGraphene under projects CONGRAN and ENTS as well as by the DFG. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:97181 Serial 3168
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Author de Oliveira, E.L.; Albuquerque, E.L.; de Sousa, J.S.; Farias, G.A.; Peeters, F.M.
Title Configuration-interaction excitonic absorption in small Si/Ge and Ge/Si core/shell nanocrystals Type A1 Journal article
Year 2012 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 116 Issue 7 Pages 4399-4407
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The excitonic properties of Si(core)/Ge(shell) and Ge(core)/Si(shell) nanocrystals (NC's) with diameters of similar to 1.9 nm are investigated using a combination density functional ab initio method to obtain the single particle wave functions and a configuration interaction method to compute the exciton fine structure and absorption coefficient. These core/shell structures exhibit type II confinement, which is more pronounced for the Si/Ge NC as a consequence of strain. The absorption coefficients of these NC's exhibit a single dominant peak, which has a much larger oscillator strength than the multipeaks found for pure Si and Ge NC's. The exciton lifetime in Si, Ge, and Ge/Si shows a small i:emperature dependence in the range 10-300 K, whereas in Si/Ge, the exciton lifetime decreases more than an order of magnitude in the same temperature range.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000301156500007 Publication Date 2012-01-04
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 44 Open Access
Notes ; The authors acknowledge financial support from CNPq and the bilateral program between Flanders and Brazil and the Belgian Science Foundation (IAP). ; Approved Most recent IF: 4.536; 2012 IF: 4.814
Call Number UA @ lucian @ c:irua:113045 Serial 482
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Author Tirumalasetty, G.K.; van Huis, M.A.; Kwakernaak, C.; Sietsma, J.; Sloof, W.G.; Zandbergen, H.W.
Title Deformation-induced austenite grain rotation and transformation in TRIP-assisted steel Type A1 Journal article
Year 2012 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 60 Issue 3 Pages 1311-1321
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Uniaxial straining experiments were performed on a rolled and annealed Si-alloyed TRIP (transformation-induced plasticity) steel sheet in order to assess the role of its microstructure on the mechanical stability of austenite grains with respect to martensitic transformation. The transformation behavior of individual metastable austenite grains was studied both at the surface and inside the bulk of the material using electron back-scattered diffraction (EBSD) and X-ray diffraction (XRD) by deforming the samples to different strain levels up to about 20%. A comparison of the XRD and EBSD results revealed that the retained austenite grains at the surface have a stronger tendency to transform than the austenite grains in the bulk of the material. The deformation-induced changes of individual austenite grains before and after straining were monitored with EBSD. Three different types of austenite grains can be distinguished that have different transformation behaviors: austenite grains at the grain boundaries between ferrite grains, twinned austenite grains, and embedded austenite grains that are completely surrounded by a single ferrite grain. It was found that twinned austenite grains and the austenite grains present at the grain boundaries between larger ferrite grains typically transform first, i.e. are less stable, in contrast to austenite grains that are completely embedded in a larger ferrite grain. In the latter case, straining leads to rotations of the harder austenite grain within the softer ferrite matrix before the austenite transforms into martensite. The analysis suggests that austenite grain rotation behavior is also a significant factor contributing to enhancement of the ductility. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos (up) 000301157900054 Publication Date 2011-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.301 Times cited 80 Open Access
Notes Approved Most recent IF: 5.301; 2012 IF: 3.941
Call Number UA @ lucian @ c:irua:97210 Serial 630
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Author Li, M.R.; Adem, U.; McMitchell, S.R.C.; Xu, Z.; Thomas, C.I.; Warren, J.E.; Giap, D.V.; Niu, H.; Wan, X.; Palgrave, R.G.; Schiffmann, F.; Cora, F.; Slater, B.; Burnett, T.L.; Cain, M.G.; Abakumov, A.M.; Van Tendeloo, G.; Thomas, M.F.; Rosseinsky, M.J.; Claridge, J.B.;
Title A polar corundum oxide displaying weak ferromagnetism at room temperature Type A1 Journal article
Year 2012 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 134 Issue 8 Pages 3737-3747
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Combining long-range magnetic order with polarity in the same structure is a prerequisite for the design of (magnetoelectric) multiferroic materials. There are now several demonstrated strategies to achieve this goal, but retaining magnetic order above room temperature remains a difficult target. Iron oxides in the +3 oxidation state have high magnetic ordering temperatures due to the size of the coupled moments. Here we prepare and characterize ScFeO3 (SFO), which under pressure and in strain-stabilized thin films adopts a polar variant of the corundum structure, one of the archetypal binary oxide structures. Polar corundum ScFeO3 has a weak ferromagnetic ground state below 356 K-this is in contrast to the purely antiferromagnetic ground state adopted by the well-studied ferroelectric BiFeO3.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000301161600027 Publication Date 2012-01-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7863;1520-5126; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.858 Times cited 48 Open Access
Notes Approved Most recent IF: 13.858; 2012 IF: 10.677
Call Number UA @ lucian @ c:irua:97200 Serial 2658
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Author Sels, D.; Brosens, F.; Magnus, W.
Title On the path integral representation of the Wigner function and the BarkerMurray ansatz Type A1 Journal article
Year 2012 Publication Physics letters : A Abbreviated Journal Phys Lett A
Volume 376 Issue 6/7 Pages 809-812
Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)
Abstract The propagator of the Wigner function is constructed from the WignerLiouville equation as a phase space path integral over a new effective Lagrangian. In contrast to a paper by Barker and Murray (1983) [1], we show that the path integral can in general not be written as a linear superposition of classical phase space trajectories over a family of non-local forces. Instead, we adopt a saddle point expansion to show that the semiclassical Wigner function is a linear superposition of classical solutions for a different set of non-local time dependent forces. As shown by a simple example the specific form of the path integral makes the formulation ideal for Monte Carlo simulation.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000301167300005 Publication Date 2012-01-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0375-9601; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.772 Times cited 7 Open Access
Notes ; ; Approved Most recent IF: 1.772; 2012 IF: 1.766
Call Number UA @ lucian @ c:irua:94006 Serial 2445
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Author Berdiyorov, G.R.; Hernández-Nieves, A.D.; Milošević, M.V.; Peeters, F.M.; Dominguez, D.
Title Flux-quantum-discretized dynamics of magnetic flux entry, exit, and annihilation in current-driven mesoscopic type-I superconductors Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 9 Pages 092502-092502,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study nonlinear flux dynamics in a current-carrying type-I superconductor. The stray magnetic field of the current induces the intermediate state, where nucleation of flux domains is discretized to a single fluxoid at a time, while their final shape (tubular or laminar), size, and nucleation rate depend on applied current and edge conditions. The current induces opposite flux domains on opposite sides of the sample, and subsequently drives them to annihilation-which is also discretized, as a sequence of vortex-antivortex pairs. The discretization of both nucleation and annihilation leaves measurable traces in the voltage across the sample and in locally probed magnetization. The reported dynamic phenomena thus provide an unambiguous proof of a flux quantum being the smallest building block of the intermediate state in type-I superconductors.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301183000002 Publication Date 2012-03-07
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 14 Open Access
Notes ; This work was supported by the Belgian Science Policy (IAP), the Flemish Science Foundation (FWO-Vl), and the collaborative project FWO-MINCyT (Project No. FW/08/01). G. R. B. and A. D. H acknowledge support from FWO-Vl. A. D. H. and D. D. acknowledge support from CONICET, CNEA, and ANPCyT (Grant No. PICT07-824). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:97180 Serial 1243
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Author Vernimmen, J.; Meynen, V.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Cool, P.
Title Formation of a Ti-siliceous trimodal material with macroholes, mesopores and zeolitic features via a one-pot templating synthesis Type A1 Journal article
Year 2012 Publication Journal of porous materials Abbreviated Journal J Porous Mat
Volume 19 Issue 2 Pages 153-160
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract Based on a facile one-pot templating synthesis, using a TS-1 zeolite recipe whereby part of the zeolite structure directing agent is replaced by a mesopore templating agent, a trimodal material is formed. The resulting meso-TSM material combines mesoporosity (Ti-MCM-41) with zeolitic features (TS-1) and a unique sheet-like morphology with uniform macroporous voids (macroholes). Moreover, the macrohole formation, mesoporosity and zeolitic properties of the meso-TSM material can be controlled in a straightforward way by adjusting the length of the hydrothermal treatment. This newly developed material may imply great potential for catalytic redox applications and diffusion limitated processes because of its highly tunable character in all three dimensions (micro-, meso- and macroporous scale).
Address
Corporate Author Thesis
Publisher Kluwer Academic Place of Publication Boston, Mass. Editor
Language Wos (up) 000301187600002 Publication Date 2011-03-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1380-2224;1573-4854; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.624 Times cited 2 Open Access
Notes Fwo; Goa Approved Most recent IF: 1.624; 2012 IF: 1.348
Call Number UA @ lucian @ c:irua:88367 Serial 1257
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Author Pachoud, E.; Bréard, Y.; Martin, C.; Maignan, A.; Abakumov, A.M.; Suard, E.; Smith, R.I.; Suchomel, M.R.
Title Bi0.75Sr0.25FeO3-\delta : revealing order/disorder phenomena by combining diffraction techniques Type A1 Journal article
Year 2012 Publication Solid state communications Abbreviated Journal Solid State Commun
Volume 152 Issue 5 Pages 331-336
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The local and long range structure of polycrystalline samples of Bi0.75Sr0.25FeO3-delta has been probed by neutron and synchrotron X-ray diffraction coupled with transmission electron microscopy. It is found that the long range structure on average can be described by the cubic space group Pm-3m (a(p) congruent to 3.951 angstrom). However, the refinements revealed large atomic displacements for the (Bi, Sr) cations and the oxygen atoms from their ideal positions. The electron microscopy study indicates the existence of local phenomena like local ordering of oxygen vacancies, which are segregated at the randomly spaced parallel (FeO2-delta) planes, or the existence of region of different symmetry, probably R3c. At room temperature, the compound exhibits G-type antiferromagnetism (T-N congruent to 650 K) with a magnetic moment of congruent to 3.7 mu(B). (C) 2012 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos (up) 000301329200001 Publication Date 2011-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.554 Times cited 6 Open Access
Notes Approved Most recent IF: 1.554; 2012 IF: 1.534
Call Number UA @ lucian @ c:irua:97820 Serial 3516
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Author Abreu, Y.; Cruz, C.M.; van Espen, P.; Pérez, C.; Piñera, I.; Leyva, A.; Cabal, A.E.
Title Electric field gradient calculations in ZnO samples implanted with 111In(111Cd) Type A1 Journal article
Year 2012 Publication Solid state communications Abbreviated Journal
Volume 152 Issue 5 Pages 399-402
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract A first-principles study of the electric field gradient (EFG) calculated for ideal and In-111(Cd-111) implanted ZnO samples is reported in the present work. The study was made for ZnO ideal hexagonal structures and supercells were introduced in order to consider the possible implantation environments. The calculation was done using the “WIEN2k” code within the density functional theory, the exchange and correlation effects were determined by the GGA approximation. Three possible In-111(Cd-111) implantation configurations were studied, one substitutional incorporation at cation site and two interstitials. The obtained EFG values for the ideal structure and the substitutional site are in good agreement with the experimental reports measured by perturbed angular correlation (PAC) and high precision nuclear magnetic resonance (NMR). Thus, the ascription of substitutional incorporation of In-111(Cd-111) probe atom at the ZnO cation site after annealing was confirmed. (C) 2011 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301329200016 Publication Date 2011-12-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098 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:97821 Serial 7857
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Author Bouvier, S.; Benmhenni, N.; Tirry, W.; Gregory, F.; Nixon, M.E.; Cazacu, O.; Rabet, L.
Title Hardening in relation with microstructure evolution of high purity \alpha-titanium deformed under monotonic and cyclic simple shear loadings at room temperature Type A1 Journal article
Year 2012 Publication Materials science and engineering: part A: structural materials: properties, microstructure and processing Abbreviated Journal Mat Sci Eng A-Struct
Volume 535 Issue Pages 12-21
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The aim of this paper is to gain understanding of the quasi-static, large strain deformation behavior at room-temperature of high-purity alpha-Ti with an initial split-basal texture. Simple shear tests were conducted along different directions in order to quantify the material's anisotropy and hardening evolution for different strain paths such as monotonic, Bauschinger, and cyclic loadings. The stress-strain curves indicate that the material displays strong anisotropy in the flow behavior. In order to capture the link between microstructure evolution (occurrence of twinning, grain size evolution, etc.) and the macroscopic response, a thoroughly detailed multi-scale characterization using scanning electron microscope (SEM) observations and electron backscattered diffraction (EBSD) analysis was also conducted. Specifically, EBSD analyses indicate that the twin activity and grain fragmentation are responsible for the observed difference between the macroscopic hardening rates corresponding to different directions and loading paths. (C) 2011 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos (up) 000301402400003 Publication Date 2011-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-5093; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.094 Times cited 22 Open Access
Notes Approved Most recent IF: 3.094; 2012 IF: 2.108
Call Number UA @ lucian @ c:irua:97824 Serial 1410
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Author Coghe, F.; Tirry, W.; Rabet, L.; Schryvers, D.; Van Houtte, P.
Title Importance of twinning in static and dynamic compression of a Ti-6Al-4V titanium alloy with an equiaxed microstructure Type A1 Journal article
Year 2012 Publication Materials science and engineering: part A: structural materials: properties, microstructure and processing Abbreviated Journal Mat Sci Eng A-Struct
Volume 537 Issue Pages 1-10
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Whereas deformation twinning is known to be an important deformation mechanism for hexagonal materials like magnesium and pure titanium, so far almost no literature exists on the twinning behaviour of the Ti-6Al-4V alloy. In this work it was shown that the activation of twinning as a deformation mechanism could have a pronounced effect on the mechanical behaviour of the Ti-6Al-4V alloy. This effect is even more pronounced under dynamic loading conditions. Transmission electron microscopy showed that only the {1 0 1 2}{1 0 1 1} tensile twin system was activated under certain loading conditions. Light-optical microscopy and electron backscatter diffraction data were afterwards used to experimentally determine the twin fractions. The importance of twinning for the texture evolution was also studied. It was shown that even small twin fractions can lead to distinct texture features, especially due to the discrete reorientation of the c-axes. The experimental results were compared to simulated results that were obtained with a viscoplastic self-consistent crystal plasticity code, after experimental validation that twinning can be reliably modelled as a unidirectional slip system. Although good agreement was obtained for the experimental and simulated stress-strain curves, the simulated results concerning twinning correlated well only on a qualitative basis as the simulated twin fractions were systematically higher than the experimental fractions. This seems to strengthen the hypothesis made by other research groups that complete grains might reorient by twinning. (C) 2011 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos (up) 000301473300001 Publication Date 2011-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-5093; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.094 Times cited 35 Open Access
Notes Approved Most recent IF: 3.094; 2012 IF: 2.108
Call Number UA @ lucian @ c:irua:97818 Serial 1565
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Author Aghaei, M.; Lindner, H.; Bogaerts, A.
Title Effect of a mass spectrometer interface on inductively coupled plasma characteristics : a computational study Type A1 Journal article
Year 2012 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom
Volume 27 Issue 4 Pages 604-610
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract An inductively coupled plasma connected to a mass spectrometer interface (sampling cone) is computationally investigated. Typical plasma characteristics, such as gas flow velocity, plasma temperature and electron density, are calculated in two dimensions (cylindrical symmetry) and compared with and without a mass spectrometer sampling interface. The results obtained from our model compare favorably with experimental data reported in the literature. A dramatic increase in the plasma velocity is reported in the region close to the interface. Furthermore, a cooled metal interface lowers the plasma temperature and electron density on the axial channel very close to the sampling cone but the corresponding values in the off axial regions are increased. Therefore, the effect of the interface strongly depends on the measurement position. It is shown that even a small shift from the actual position of the sampler leads to a considerable change of the results.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000301496700005 Publication Date 2012-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0267-9477;1364-5544; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.379 Times cited 18 Open Access
Notes Approved Most recent IF: 3.379; 2012 IF: 3.155
Call Number UA @ lucian @ c:irua:97386 Serial 791
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Author Nayuk, R.; Zacher, D.; Schweins, R.; Wiktor, C.; Fischer, R.A.; Van Tendeloo, G.; Huber, K.
Title Modulated formation of MOF-5 nanoparticles : a SANS analysis Type A1 Journal article
Year 2012 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 116 Issue 10 Pages 6127-6135
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract MOF-5 nanoparticles were prepared by mixing a solution of [Zn4O(C6H5COO)(6)] with a solution of benzene-1,4-dicarboxylic acid in DMF at ambient conditions. The former species mimics as a secondary building unit (SBU), and the latter acts as linker. Mixing of the two solutions induced the formation of MOF-5 nanoparticles in dilute suspension. The applied conditions were identified as suitable for a closer investigation of the particle formation process by combined light and small angle neutron scattering (SANS). Scattering analysis revealed a significant impact of the molar ratio of the two components in the reaction mixture. Excessive use of the building unit slowed down the process. A similar effect was observed upon addition of 4n-decylbenzoic acid, which is supposed to act as a modulator. The formation mechanism leads to initial intermediates, which turn into cubelike nanoparticles with a diameter of about 60-80 nm. This initial stage is followed by an extended formation period, where nucleation proceeds over hours, leading to an increasing number of nanoparticles with the same final size of 60-80 nm.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000301509600020 Publication Date 2012-02-16
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 24 Open Access
Notes Approved Most recent IF: 4.536; 2012 IF: 4.814
Call Number UA @ lucian @ c:irua:97789 Serial 2163
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Author Krupińska, B.; Worobiec, A.; Rotondo, G.G.; Novaković, V.; Kontozova, V.; Ro, C.-U.; Van Grieken, R.; De Wael, K.
Title Assessment of the air quality (NO2, SO2, O3 and particulate matter) in the Plantin-Moretus Museum/Print Room in Antwerp, Belgium, in different seasons of the year Type A1 Journal article
Year 2012 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 102 Issue 1 Pages 49-53
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract The Plantin-Moretus Museum/Print Room in Antwerp, Belgium, gathers one of the most precious collections of typographical material and old printed books in the world. Rich decorations of this former printing-house and the history of the building itself underline its uniqueness. The cultural heritage (CH) objects collected in the museum, in particular books and manuscripts are vulnerable to the atmospheric pollution and can be irreversibly damaged. To assess the air quality inside the museum, four consecutive sampling campaigns were performed in each season of the year. The gas monitoring of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3) was carried out outside the building, in galleries and in showcases by means of using diffusive samplers. The particulate matter (PM) was collected in bulk form and as single particles and then analysed with use of energy dispersive X-ray fluorescence (EDXRF) and electron probe micro-analyser (EPMA), respectively. The museum complex turned out to show good protection against gaseous pollutants, especially SO2 and O3. The concentrations of these pollutants were significantly reduced inside the building in comparison to the outdoor ones. Similar protective character of the museum complex was established in case of the coarse fraction of PM; however with some limitations. Single particle analysis showed that the relative abundance of carbon-rich particles inside the museum was greater than outside. Moreover, these particles contributed more to the fine fraction of PM than to the coarse fraction. Therefore, for better preservation of cultural heritage, special attention should be paid to the small particles and their distribution within the museum.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301559100007 Publication Date 2011-11-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 25 Open Access
Notes ; The presented work was realised in the frame of the project Preventive conservation/preservation in the museum Plantin-Moretus/Prentenkabinet, Antwerp, financed by the Flemish Government. Special thanks are due to Mrs Hanne Moris and Mrs Elke van Herck and all the staff of the Museum Plantin-Moretus/Print Room in Antwerp for their sincere interest in this work and their eager assistance during all the sampling campaigns. Barbara Krupinska is supported as PhD student by the Flemish Fund for Scientific Research (FWO, Belgium). ; Approved Most recent IF: 3.034; 2012 IF: 2.879
Call Number UA @ admin @ c:irua:94466 Serial 5483
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Author Kao, K.-H.; Verhulst, A.S.; Vandenberghe, W.G.; Sorée, B.; Groeseneken, G.; De Meyer, K.
Title Modeling the impact of junction angles in tunnel field-effect transistors Type A1 Journal article
Year 2012 Publication Solid state electronics Abbreviated Journal Solid State Electron
Volume 69 Issue Pages 31-37
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We develop an analytical model for a tunnel field-effect transistor (TFET) with a tilted source junction angle. The tunnel current is derived by using circular tunnel paths along the electric field. The analytical model predicts that a smaller junction angle improves the TFET performance, which is supported by device simulations. An analysis is also made based on straight tunnel paths and tunnel paths corresponding to the trajectory of a classical particle. In all the aforementioned cases, the same conclusions are obtained. A TFET configuration with an encroaching polygon source junction is studied to analyze the junction angle dependence at the smallest junction angles. The improvement of the subthreshold swing (SS) with decreasing junction angle can be achieved by using thinner effective oxide thickness, smaller band gap material and longer encroaching length of the encroaching junction. A TFET with a smaller junction angle on the source side also has an innate immunity against the degradation of the fringing field from the gate electrode via a high-k spacer. A large junction angle on the drain side can suppress the unwanted ambipolar current of TFETs. (c) 2011 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos (up) 000301561600009 Publication Date 2012-01-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1101; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.58 Times cited 9 Open Access
Notes ; We acknowledge the input on nanowire processing of Rita Rooyackers and useful discussions with Wim Magnus. William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was also supported by imec's Industrial Affiliation Program. ; Approved Most recent IF: 1.58; 2012 IF: 1.482
Call Number UA @ lucian @ c:irua:97816 Serial 2145
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Author Ang, F.; Van Passel, S.
Title Beyond the environmentalist's paradox and the debate on weak versus strong sustainability Type A1 Journal article
Year 2012 Publication Bioscience Abbreviated Journal Bioscience
Volume 62 Issue 3 Pages 251-259
Keywords A1 Journal article; Economics; Engineering Management (ENM)
Abstract Environmentalists generally argue that ecological damage will (eventually) lead to declines in human well-being. From this perspective, the recent introduction of the “environmentalist's paradox” in BioScience by Raudsepp-Hearne and colleagues (2010) is particularly significant. In essence, Raudsepp-Hearne and colleagues (2010) claimed that although ecosystem services have been degraded, human well-being-paradoxically-has increased. In this article, we show that this debate is in fact rooted in a broader discussion on weak sustainability versus strong sustainability (the substitutability of human-made capital for natural capital). We warn against the reductive nature of focusing only on a stock flow framework in which a natural-capital stock produces ecosystem services. Concretely, we recommend a holistic approach in which the complexity, irreversibility, uncertainty, and ethical predicaments intrinsic to the natural environment and its connections to humanity are also considered.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301561900008 Publication Date 2012-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0006-3568 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.378 Times cited 17 Open Access
Notes ; We thank three anonymous reviewers for their helpful comments. This aiticle has benefited considerably from interesting discussions (especially with Liesbet Vranken) at the 13th Belgian PhD Symposium of Agricultural and Natural Resource Economics, Brussels, on 27 April 2011. We are grateful for the financial support of the European Fund for Regional Development project 475, Closing the Circle. ; Approved Most recent IF: 5.378; 2012 IF: 4.739
Call Number UA @ admin @ c:irua:127559 Serial 6160
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Author Piñera, I.; Cruz, C.M.; van Espen, P.; Abreu, Y.; Leyva, A.
Title Study of dpa distributions in electron irradiated YBCO slabs through MCCM algorithm Type A1 Journal article
Year 2012 Publication Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms Abbreviated Journal
Volume 274 Issue Pages 191-194
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The Monte Carlo assisted Classical Method (MCCM) consists on a calculation procedure for determining the displacements per atom (dpa) distribution in solid materials. This algorithm allows studying the gamma and electron irradiation damage in different materials. It is based on the electrons elastic scattering classic theories and the use of Monte Carlo simulation for the physical processes involved. The present study deals with the Monte Carlo simulation of electron irradiation effects on YBa2Cu3O7-x (YBCO) slabs using the MCNPX code system. Displacements per atom distributions are obtained through the MCCM for electron irradiation up to 10 MeV. In-depth dpa profiles for electrons and positrons are obtained and analysed. Also, dpa contributions from each atomic specie in the material are calculated. It was found that the dpa distribution is more homogeneous in the material volume when increasing energy of incident electrons. Also, the dpa produced by positrons has no relevance when irradiating with electrons, in contrast with previous similar gamma irradiation studies. All the results are presented and discussed in this contribution. (C) 2011 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301611900031 Publication Date 2011-12-05
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:97819 Serial 8595
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Author Maes, D.; Van Passel, S.
Title Interference of regional support policies on the economic and environmental performance of a hybrid cogeneration-solar panel energy system Type A1 Journal article
Year 2012 Publication Energy Policy Abbreviated Journal Energ Policy
Volume 42 Issue Pages 670-680
Keywords A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM)
Abstract This paper assesses unintentional interference between different public policies promoting energy efficiency and renewable energy. The paper develops a methodology to study the interference by analysing the economic and technical behaviour of a hybrid energy system. The hybrid energy system in this case consists of an existing cogeneration unit extended with a new installation of thermal solar panels. This puts two complementary heating technologies in juxtaposition. The two technologies are supported with distinct regional support instruments in each region. The design and operation of the energy system is optimised from the point of view of the investor according to the different support instruments. The optimal configuration is analysed as well as its effect on reduced CO2-emissions during the lifetime of the project. The methodology is applied to a case-study for two neighbouring regions, the Netherlands and Flanders. The policies in the Netherlands show a beneficial synergy. In Flanders, the hybrid energy system is not interesting, indicating unbalanced high support for cogeneration in this case. From the point of view of the authorities, a more balanced regional policy as in the Netherlands provides a larger CO2-emission reduction for a smaller cost. (C) 2012 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301616000066 Publication Date 2012-01-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0301-4215; 1873-6777 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.14 Times cited 4 Open Access
Notes ; The authors would especially like to thank Davy Duelen for the excellent case-study and data collection that enabled the present paper. The help and information provided by Pierre Gijsen also made the detailed assessment possible. We are also indebted to two anonymous reviewers, whose remarks strongly improved the paper. This project has been financed by the Impulse-project of the tUL (transnational University Limburg). ; Approved Most recent IF: 4.14; 2012 IF: 2.743
Call Number UA @ admin @ c:irua:127558 Serial 6220
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Author Cagno, S.; Favaretto, L.; Mendera, M.; Izmer, A.; Vanhaecke, F.; Janssens, K.
Title Evidence of early medieval soda ash glass in the archaeological site of San Genesio (Tuscany) Type A1 Journal article
Year 2012 Publication Journal of archaeological science Abbreviated Journal J Archaeol Sci
Volume 39 Issue 5 Pages 1540-1552
Keywords A1 Journal article; Philosophy; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The early medieval period marks an important turning point in the history of glassmaking, since it comprises the transition period between the mineral-based silica-soda-lime glass of the Roman tradition and the plant ash-based glass. With the aim of expanding the knowledge on the glass recipes and technologies of this period, 37 glass samples were analyzed, originating from the archaeological excavations of San Genesio (Tuscany) and dated from the fourth to the eleventh century. The major and minor element concentrations were measured with SEM-EDX, while the trace elements were quantified with LA-ICP-MS. The results were compared with published compositions of glass samples of similar age in order to highlight differences and similarities. The results offer a very interesting view on the glass circulation in the religious/residential/manufacturing center of San Genesio in the early medieval period. Most of the glass has a typical late-Roman composition, but some glass fragments are identified as soda ash glass. These are among the earliest medieval ash-fluxed glasses ever found in the Italian peninsula. (C) 2011 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301620900034 Publication Date 2012-01-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0305-4403 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.602 Times cited 24 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. ; Approved Most recent IF: 2.602; 2012 IF: 1.889
Call Number UA @ admin @ c:irua:98251 Serial 5618
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Author Michel, K.H.; Verberck, B.
Title Theory of rigid-plane phonon modes in layered crystals Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 9 Pages 094303-094303,11
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The lattice dynamics of low-frequency rigid-plane modes in metallic (graphene multilayers, GML) and in insulating (hexagonal boron-nitride multilayers, BNML) layered crystals is investigated. The frequencies of shearing and compression (stretching) modes depend on the layer number N and are presented in the form of fan diagrams. The results for GML and BNML are very similar. In both cases, only the interactions (van der Waals and Coulomb) between nearest-neighbor planes are effective, while the interactions between more distant planes are screened. A comparison with recent Raman scattering results on low-frequency shear modes in GML [Tan et al., Nat. Mater., in press, doi: 10.1038/nmat3245, (2012)] is made. Relations with the low-lying rigid-plane phonon dispersions in the bulk materials are established. Master curves, which connect the fan diagram frequencies for any given N, are derived. Static and dynamic thermal correlation functions for rigid-layer shear and compression modes are calculated. The results might be of use for the interpretation of friction force experiments on multilayer crystals.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000301646000006 Publication Date 2012-03-19
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 38 Open Access
Notes ; The authors are indebted to J. Maultzsch for bringing Ref. 20 to their attention. They thank D. Lamoen, F.M. Peeters, B. Trauzettel, and C. Van Haesendonck for useful discussions. This work has been financially supported by the Research Foundation Flanders (FWO). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:97787 Serial 3619
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Author Neek-Amal, M.; Peeters, F.M.
Title Effect of grain boundary on the buckling of graphene nanoribbons Type A1 Journal article
Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 100 Issue 10 Pages 101905-101905,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The buckling of graphene nano-ribbons containing a grain boundary is studied using atomistic simulations where free and supported boundary conditions are invoked. We consider the buckling transition of two kinds of grain boundaries with special symmetry. When graphene contains a large angle grain boundary with theta = 21.8 degrees, the buckling strains are larger than those of perfect graphene when the ribbons with free (supported) boundary condition are subjected to compressive tension parallel (perpendicular) to the grain boundary. This is opposite for the results of theta = 32.2 degrees. The shape of the deformations of the buckled graphene nanoribbons depends on the boundary conditions, the presence of the particular used grain boundaries, and the direction of applied in-plane compressive tension. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3692573]
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000301655500021 Publication Date 2012-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 18 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.411; 2012 IF: 3.794
Call Number UA @ lucian @ c:irua:97794 Serial 809
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Author Van Aert, S.; van den Broek, W.; Goos, P.; van Dyck, D.
Title Model-based electron microscopy : from images toward precise numbers for unknown structure parameters Type A1 Journal article
Year 2012 Publication Micron Abbreviated Journal Micron
Volume 43 Issue 4 Pages 509-515
Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab
Abstract Statistical parameter estimation theory is proposed as a method to quantify electron microscopy images. It aims at obtaining precise and accurate values for the unknown structure parameters including, for example, atomic column positions and types. In this theory, observations are purely considered as data planes, from which structure parameters have to be determined using a parametric model describing the images. The method enables us to measure positions of atomic columns with a precision of the order of a few picometers even though the resolution of the electron microscope is one or two orders of magnitude larger. Moreover, small differences in averaged atomic number, which cannot be distinguished visually, can be quantified using high-angle annular dark field scanning transmission electron microscopy images. Finally, it is shown how to optimize the experimental design so as to attain the highest precision. As an example, the optimization of the probe size for nanoparticle radius measurements is considered. It is also shown how to quantitatively balance signal-to-noise ratio and resolution by adjusting the probe size.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos (up) 000301702400003 Publication Date 2011-11-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0968-4328; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.98 Times cited 7 Open Access
Notes Fwo Approved Most recent IF: 1.98; 2012 IF: 1.876
Call Number UA @ lucian @ c:irua:94114 Serial 2099
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Author Xu, Q.; Zandbergen, H.W.; van Dyck, D.
Title Imaging from atomic structure to electronic structure Type A1 Journal article
Year 2012 Publication Micron Abbreviated Journal Micron
Volume 43 Issue 4 Pages 524-531
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract This paper discusses the possibility of retrieving the electron distribution (with highlighted valence electron distribution information) of materials from recorded HREM images. This process can be achieved by solving two inverse problems: reconstruction of the exit wave and reconstruction of the electron distribution from exit waves. The first inverse problem can be solved using a focal series reconstruction method. We show that the second inverse problem can be solved by combining a series of exit waves recorded at different thickness conditions. This process is designed based on an improved understanding of the dynamical scattering process. It also explains the fundamental difficulty of obtaining the valence electron distribution information and the basis of our solution.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos (up) 000301702400005 Publication Date 2011-11-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0968-4328; ISBN Additional Links UA library record; WoS full record
Impact Factor 1.98 Times cited Open Access
Notes Fwo Approved Most recent IF: 1.98; 2012 IF: 1.876
Call Number UA @ lucian @ c:irua:93634 Serial 1553
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Author Goris, B.; van Huis, M.A.; Bals, S.; Zandbergen, H.W.; Manna, L.; Van Tendeloo, G.
Title Thermally induced structural and morphological changes of CdSe/CdS octapods Type A1 Journal article
Year 2012 Publication Small Abbreviated Journal Small
Volume 8 Issue 6 Pages 937-942
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Branched nanostructures are of great interest because of their promising optical and electronic properties. For successful and reliable integration in applications such as photovoltaic devices, the thermal stability of the nanostructures is of major importance. Here the different domains (CdSe cores, CdS pods) of the heterogeneous octapods are shown to have different thermal stabilities, and heating is shown to induce specific shape changes. The octapods are heated from room temperature to 700 °C, and investigated using (analytical and tomographic) transmission electron microscopy (TEM). At low annealing temperatures, pure Cd segregates in droplets at the outside of the octapods, indicating non-stochiometric composition of the octapods. Furthermore, the tips of the pods lose their faceting and become rounded. Further heating to temperatures just below the sublimation temperature induces growth of the zinc blende core at the expense of the wurtzite pods. At higher temperatures, (500700 °C), sublimation of the octapods is observed in real time in the TEM. Three-dimensional tomographic reconstructions reveal that the four pods pointing into the vacuum have a lower thermal stability than the four pods that are in contact with the support.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos (up) 000301718800021 Publication Date 2012-01-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1613-6810; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.643 Times cited 20 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 8.643; 2012 IF: 7.823
Call Number UA @ lucian @ c:irua:95040 Serial 3633
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Author Wang, A.; Van Aert, S.; Goos, P.; van Dyck, D.
Title Precision of three-dimensional atomic scale measurements from HRTEM images : what are the limits? Type A1 Journal article
Year 2012 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 114 Issue Pages 20-30
Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab
Abstract In this paper, we investigate to what extent high resolution transmission electron microscopy images can be used to measure the mass, in terms of thickness, and surface profile, corresponding to the defocus offset, of an object at the atomic scale. Therefore, we derive an expression for the statistical precision with which these object parameters can be estimated in a quantitative analysis. Evaluating this expression as a function of the microscope settings allows us to derive the optimal microscope design. Acquiring three-dimensional structure information in terms of thickness turns out to be much more difficult than obtaining two-dimensional information on the projected atom column positions. The attainable precision is found to be more strongly affected by processes influencing the image contrast, such as phonon scattering, than by the specific choice of microscope settings. For a realistic incident electron dose, it is expected that atom columns can be distinguished with single atom sensitivity up to a thickness of the order of the extinction distance. A comparable thickness limit is determined to measure surface steps of one atom. An increase of the electron dose shifts the limiting thickness upward due to an increase in the signal-to-noise ratio.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000301954300003 Publication Date 2012-01-06
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 5 Open Access
Notes Fwo Approved Most recent IF: 2.843; 2012 IF: 2.470
Call Number UA @ lucian @ c:irua:94116 Serial 2692
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