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Author Vodolazov, D.Y.; Peeters, F.M.
Title Strong influence of nonlocal nonequilibrium effects on the dynamics of the order parameter in a phase-slip center: ring studies Type A1 Journal article
Year (up) 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 18 Pages 184521,1-184521,7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the influence of the inelastic relaxation time τ̃E of the quasiparticle distribution function f(E) on the phase slip process in quasi-one-dimensional superconducting rings at a temperature close to the critical temperature Tc. We find that the initial time of growth of the order parameter |Δ| in the phase slip core after the phase slip is a nonmonotonic function of τ̃E which has a maximum at τ̃E≃τ̃GL=πℏ/8kB(Tc−T) and has a tendency to saturate for large τ̃E⪢τ̃GL. The effective heating of the electron subsystem due to the increase in |Δ| in the phase slip center together with the above effect result in a nonmonotonic dependence of the number of subsequent phase slips on τ̃E in rings of relatively large radius (in which each phase slip reduces the current density to a small fraction of its initial value). During the phase slip process the order parameter distribution has two peaks near the phase slip core due to the diffusion of the nonequilibrium quasiparticles from that region.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278141800100 Publication Date 2010-05-19
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 5 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). D.Y.V. also acknowledges support from the Russian Foundation for Basic Research, Federal Target Programme “Scientific and scientific-pedagogical personnel of innovative Russia in 2009-2013” and Dynasty Foundation. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83305 Serial 3182
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Author Verlooy, P.L.H.; Robeyns, K.; van Meervelt, L.; Lebedev, O.I.; Van Tendeloo, G.; Martens, J.A.; Kirschhock, C.E.A.
Title Synthesis and characterization of the new cyclosilicate hydrate (hexamethyleneimine)4.[Si8O16(OH)4].12H2O Type A1 Journal article
Year (up) 2010 Publication Microporous and mesoporous materials: zeolites, clays, carbons and related materials Abbreviated Journal Micropor Mesopor Mat
Volume 130 Issue 1/3 Pages 14-20
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new cyclosilicate hydrate with composition (C6H14N)4·[Si8O16(OH)4]·12H2O was crystallized and the structure determined by single-crystal X-ray diffraction. The structure, described by the tetragonal space group I41/a, with unit cell dimensions of a = 39.2150(2) Å and c = 14.1553(2) Å, contains columns of hydrogen-bonded cubic octamer silicate anions. The space between silicate columns holds hydrogen-bonded water and protonated hexamethyleneimine molecules compensating the negative charge of the silicate. The crystal water can be removed resulting in a rearrangement of the columns into orthorhombic symmetry. Removal of the organic moiety causes amorphisation. Flash evacuation results in a new microporous material with pore volumes typical of a zeolite.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000275702600003 Publication Date 2009-10-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1387-1811; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.615 Times cited 5 Open Access
Notes Approved Most recent IF: 3.615; 2010 IF: 3.220
Call Number UA @ lucian @ c:irua:82448 Serial 3418
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Author Leroux, F.; Gysemans, M.; Bals, S.; Batenburg, K.J.; Snauwaert, J.; Verbiest, T.; van Haesendonck, C.; Van Tendeloo, G.
Title Three-dimensional characterization of helical silver nanochains mediated by protein assemblies Type A1 Journal article
Year (up) 2010 Publication Advanced materials Abbreviated Journal Adv Mater
Volume 22 Issue 19 Pages 2193-2197
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Characterization methods for the structural investigation of biotemplates for nanodevices remain widely unexplored, despite the fact that biotemplating methods for nanodevice fabrication are becoming more widespread. In this study several techniques are used to characterize the morphology and 3D distribution of silver nanoparticles deposited on insulin fibrils.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000278601400016 Publication Date 2010-03-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648;1521-4095; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 51 Open Access
Notes Esteem 026019; Fwo Approved Most recent IF: 19.791; 2010 IF: NA
Call Number UA @ lucian @ c:irua:83296 Serial 3645
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Author Efimov, K.; Xu, Q.; Feldhoff, A.
Title Transmission electron microscopy study of BA0.5Sr0.5CO0.8Fe0.2O3-\delta Perovskite decomposition at intermediate temperatures Type A1 Journal article
Year (up) 2010 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 22 Issue 21 Pages 5866-5875
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The cubic perovskite Ba(0.5)Sr(0.5)Co(0.8)Fe(0.2)O(3-delta) (denoted BSCF) is the state-of-the-art ceramic membrane material used for oxygen separation technologies above 1150 K. BSCF is a mixed oxygen-ion and electron conductor (MIEC) and exhibits one of the highest oxygen permeabilities reported so far for dense oxides. Additionally, it has excellent phase stability above 1150 K. In the intermediate temperature range (750-1100 K), however, BSCF suffers from a slow decomposition of the cubic perovskite into variants with hexagonal stacking that are barriers to oxygen transport. To elucidate details of the decomposition process, both sintered BSCF ceramic and powder were annealed for 180-240 h in ambient air at temperatures below 1123 K and analyzed by different transmission electron microscopy techniques. Aside from hexagonal perovskite Ba(0.5)Sr(0.5)CoO(3-delta) , the formation of lamellar noncubic phases was observed in the quenched samples. The structure of the lamellae with the previously unknown composition Ba(1-x)Sr(x)Co(2-y)Fe(y)O(5-delta) was found to be related to the 15R hexagonal perovskite polytype. The valence and spin-state transition of cobalt leading to a considerable diminution of its ionic radius can be considered a reason for BSCF's inherent phase instability at intermediate temperatures.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000283623700010 Publication Date 2010-10-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 117 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2010 IF: 6.400
Call Number UA @ lucian @ c:irua:95546 Serial 3720
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Author Branchaud, S.; Kam, A.; Zawadzki, P.; Peeters, F.M.; Sachrajda, A.S.
Title Transport detection of quantum Hall fluctuations in graphene Type A1 Journal article
Year (up) 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 12 Pages 121406,1-121406,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Low-temperature magnetoconductance measurements were made in the vicinity of the charge neutrality point (CNP). Two origins for the fluctuations were identified close to the CNP. At very low magnetic fields there exist only mesoscopic magnetoconductance quantum interference features which develop rapidly as a function of density. At slightly higher fields (>0.5 T), close to the CNP, additional fluctuations track the quantum Hall (QH) sequence expected for monolayer graphene. These additional features are attributed to effects of locally charging individual QH localized states. These effects reveal a precursor to the quantum Hall effect since, unlike previous transport observations of QH dot charging effects, they occur in the absence of quantum Hall plateaus or Shubnikov-de Haas oscillations. From our transport data we are able to extract parameters that characterize the inhomogeneities in our device.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000276248900026 Publication Date 2010-03-09
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 25 Open Access
Notes ; We would like to acknowledge important motivating discussions with Louis Gaudreau, Ghislain Granger, Pawel Hawrylak, Devrim Guclu, Josh Folk, and Mark Lundeberg. A. S. S. and F. M. P. acknowledge funding from CIFAR. A. S. S. and S. B. acknowledge assistance from NSERC. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:82275 Serial 3723
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Author Liu, Y.; Cheng, F.; Li, X.J.; Peeters, F.M.; Chang, K.
Title Tuning of the two electron states in quantum rings through the spin-orbit interaction Type A1 Journal article
Year (up) 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 4 Pages 1-7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effect of the Coulomb interaction on the energy spectrum and anisotropic distribution of two electron states in a quantum ring in the presence of Rashba spin-orbit interaction (RSOI) and Dresselhaus SOI (DSOI) is investigated in the presence of a perpendicular magnetic field. We find that the interplay between the RSOI and DSOI makes the single quantum ring behaves like a laterally coupled quantum dot and the interdot coupling can be tuned by changing the strengths of the SOIs. The interplay can lead to singlet-triplet state mixing and anticrossing behavior when the singlet and triplet states meet with increasing magnetic field. The two electron ground state displays a bar-bell-like spatial anisotropic distribution in a quantum ring at a specific crystallographic direction, i.e., [110] or [11̅ 0], which can be switched by reversing the direction of the perpendicular electric field. The ground state exhibits a singlet-triplet state transition with increasing magnetic field and strengths of RSOI and DSOI. An anisotropic electron distribution is predicted which can be detected through the measurement of its optical properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280234100006 Publication Date 2010-07-22
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 NSFC under Grants No. 60525405 and No. 10874175 and the Belgium Science Policy (IAP). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84087 Serial 3756
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Author van den Heuvel, W.; Tikhomirov, V.K.; Kirilenko, D.; Schildermans, N.; Chibotaru, L.F.; Vanacken, J.; Gredin, P.; Mortier, M.; Van Tendeloo, G.; Moshchalkov, V.V.
Title Ultralow blocking temperature and breakdown of the giant spin model in Er3+-doped nanoparticles Type A1 Journal article
Year (up) 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 9 Pages 094421-094421,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The magnetization of luminescent Er3+-doped PbF2 nanoparticles (formula Er0.3Pb0.7F2.3) has been studied. Despite the high concentration of the doping Er3+ ions and relatively large size (8 nm) of these nanoparticles we have found no deviation between field-cooled and zero-field-cooled magnetization curves down to T=0.35 K, which points out an ultralow blocking temperature for the reversal of magnetization. We also have found strongly deviating magnetization curves M(H/T) for different temperatures T. These results altogether show that the investigated nanoparticles are not superparamagnetic, but rather each Er3+ ion in these nanoparticles is found in a paramagnetic state down to very low temperatures, which implies the breakdown of the Néel-Brown giant spin model in the case of these nanoparticles. Calculations of magnetization within a paramagnetic model of noninteracting Er3+ ions completely support this conclusion. Due to the ultralow blocking temperature, these nanoparticles have a potential for magnetic field-induced nanoscale refrigeration with an option of their optical localization and temperature control.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281773300005 Publication Date 2010-09-13
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 11 Open Access
Notes Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:85423 Serial 3796
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Author Geurts, R.; Milošević, M.V.; Peeters, F.M.
Title Vortex matter in mesoscopic two-gap superconducting disks: influence of Josephson and magnetic coupling Type A1 Journal article
Year (up) 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 21 Pages 15
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278846600001 Publication Date 2010-06-21
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 89 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen), the Belgian Science Policy (IAP), the ESF “Nanoscience and Engineering in Superconductivity” (NES) program, and the ESF “Arrays of Quantum Dots and Josephson Junctions” network. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83933 Serial 3872
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Author Doria, M.M.; Romaguera, A.R. de C.; Peeters, F.M.
Title Vortex patterns in a mesoscopic superconducting rod with a magnetic dot Type A1 Journal article
Year (up) 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 10 Pages 104529,1-104529,11
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study a mesoscopic superconducting rod with a magnetic dot on its top having its moment oriented along the axis of symmetry. We study the dependence of the vortex pattern with the height and find that for very short and very long rods, the vortex pattern acquires a simple structure, consisting of giant and of multivortex states, respectively. In the long limit, the most stable configuration consists of two vortices, that reach the lateral surface of the rod diametrically opposed. The long rod shows reentrant behavior within some range of its radius and of the dots magnetic moment. Our results are obtained within the Ginzburg-Landau approach in the limit of no magnetic shielding.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000276248700123 Publication Date 2010-03-31
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 5 Open Access
Notes ; The three authors acknowledge CNPq and the bilateral program between Brazil and Flanders for financial support. They also make the following acknowledgments for financial support: A. R. de C. Romaguera to FACEPE, M. M. Doria to FAPERJ, and F. M. Peeters to the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IUAP), and the ESF-AQDJJ network. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:82272 Serial 3877
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Author Berdiyorov, G.R.; Milošević, M.V.; Peeters, F.M.
Title Vortices induced in a superconducting loop by asymmetric kinetic inductance and their detection in transport measurements Type A1 Journal article
Year (up) 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 14 Pages 144511,1-144511,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using time-dependent Ginzburg-Landau theory, we study the dynamic properties of a rectangular superconducting loop, which are found to depend on the position of the current leads. For asymmetric positioning of the leads, different kinetic inductance of the two paths for injected electric current leads to different critical conditions in the two branches. System self-regulates by allowing vortex entry, as vortex currents bring equilibration between the two current flows and the conventional resistive state can be realized. We also demonstrate that individual vortex entry in the loop can be detected by measuring the voltage between normal-metal leads, for applied currents comparable in magnitude to the screening currents.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000277210200107 Publication Date 2010-04-21
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 ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the ESF-NES program, and the ESF-AQDJJ network. G.R.B. acknowledges support from FWO-Vlaanderen. The authors thank S. Michotte for useful discussions. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:82804 Serial 3901
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Author Chaves, A.; Covaci, L.; Rakhimov, K.Y.; Farias, G.A.; Peeters, F.M.
Title Wave-packet dynamics and valley filter in strained graphene Type A1 Journal article
Year (up) 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 20 Pages 205430
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The time evolution of a wave packet in strained graphene is studied within the tight-binding model and continuum model. The effect of an external magnetic field, as well as a strain-induced pseudomagnetic field, on the wave-packet trajectories and zitterbewegung are analyzed. Combining the effects of strain with those of an external magnetic field produces an effective magnetic field which is large in one of the Dirac cones, but can be practically zero in the other. We construct an efficient valley filter, where for a propagating incoming wave packet consisting of momenta around the K and K' Dirac points, the outgoing wave packet exhibits momenta in only one of these Dirac points while the components of the packet that belong to the other Dirac point are reflected due to the Lorentz force. We also found that the zitterbewegung is permanent in time in the presence of either external or strain-induced magnetic fields, but when both the external and strain-induced magnetic fields are present, the zitterbewegung is transient in one of the Dirac cones, whereas in the other cone the wave packet exhibits permanent spatial oscillations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000284401600007 Publication Date 2010-11-19
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 95 Open Access
Notes ; This work was financially supported by CNPq under NanoBioEstruturas Contract No. 555183/2005-0, PRONEX/CNPq/FUNCAP, CAPES, the Bilateral program between Flanders and Brazil, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-V1) ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:95542 Serial 3905
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Author van der Linden, V.; Van de Casteele, E.; Thomas, M.S.; de Vos, A.; Janssen, E.; Janssens, K.
Title Analysis of micro computed tomography images; a look inside historic enamelled metal objects Type A1 Journal article
Year (up) 2010 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
Volume 98 Issue 2 Pages 385-392
Keywords A1 Journal article; Vision lab; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this study the usefulness of micro-Computed Tomography (µ-CT) for the in-depth analysis of enamelled metal objects was tested. Usually investigations of enamelled metal artefacts are restricted to non-destructive surface analysis or analysis of cross sections after destructive sampling. Radiography, a commonly used technique in the field of cultural heritage studies, is limited to providing two-dimensional information about a three-dimensional object (Lang and Middleton, Radiography of Cultural Material, pp. 6061, Elsevier-Butterworth-Heinemann, Amsterdam-Stoneham-London, 2005). Obtaining virtual slices and information about the internal structure of these objects was made possible by CT analysis. With this technique the underlying metal work was studied without removing the decorative enamel layer. Moreover visible defects such as cracks were measured in both width and depth and as of yet invisible defects and weaker areas are visualised. All these features are of great interest to restorers and conservators as they allow a view inside these objects without so much as touching them.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000272158200018 Publication Date 2009-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.455 Times cited 3 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 “Atom” (Research Fund University of Antwerp, Belgium), FWO (Brussels, Belgium) projects nos. G.0177.03, G.0103.04 and G.0689.06. ; Approved Most recent IF: 1.455; 2010 IF: 1.765
Call Number UA @ admin @ c:irua:80421 Serial 5469
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Author Basile, F.; Benito, P.; Bugani, S.; de Nolf, W.; Fornasari, G.; Janssens, K.; Morselli, L.; Scavetta, E.; Tonelli, D.; Vaccari, A.
Title Combined use of synchrotron-radiation-based imaging techniques for the characterization of structured catalysts Type A1 Journal article
Year (up) 2010 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 20 Issue 23 Pages 4117-4126
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Active-phase-coated metallic supports as structured catalysts are gaining attention in endothermic and exothermic processes because they improve heat transfer. The deposition of a well-adhered and stable catalyst layer on the metallic support constitutes an important feature for the successful application of the final material. In this work, coating of FeCrAlY foams is performed by a one-step electrosynthesis-deposition of hydrotalcite-type compounds, precursors of catalysts active in endothermic steam methane reforming. The catalysts are studied at different length scales by using, for the first time, a combination of several techniques: SEM/EDS and X-ray fluorescence, X-ray powder diffraction and absorption-tomography experiments on the micro- and nanoscales at a synchrotron facility. The results show that the morphology of the coating depends on the synthesis conditions and that the catalyst may be described as Ni metal crystallites dispersed on γ-Al2O3, homogeneously coating the FeCrAlY foam.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000285392900010 Publication Date 2010-09-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 24 Open Access
Notes ; The authors give thanks to Dr. Cloetens, for helping during the absorption tomography experiments, performed at ID19 of the ESRF; and P. Blauet and R. Toucolou, for helping during the mu-XRF/XRPD and nano-XRF experiments at ID22 and ID22-NI of the ESRF. The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, Italy) is gratefully acknowledged. ; Approved Most recent IF: 12.124; 2010 IF: 8.508
Call Number UA @ admin @ c:irua:85834 Serial 5525
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Author Rouchon, V.; Pellizzi, E.; Janssens, K.
Title FTIR techniques applied to the detection of gelatine in paper artifacts: from macroscopic to microscopic approach Type A1 Journal article
Year (up) 2010 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
Volume 100 Issue 3 Pages 663-669
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In order to render paper hydrophobic for ink and thus adequate for writing, gelatine has been largely used. To this day, it is still employed in conservation workshops as an adhesive or a sizing agent, for instance, during the treatment of iron gall ink manuscripts. Various types and concentrations of gelatine are recommended, depending on the desired effect, but little information is available regarding to the physical distribution of gelatine in the paper. This aspect is however determinant for a better control of conservation treatments. In this work, we investigate the possibilities offered by FTIR microscopy for the measurement of the gelatine distribution in paper. Laboratory papers were preliminary treated with different types of gelatine and then embedded in a resin and cut in thin slices. Mapping techniques enable to compare the penetration of different types of gelatine in a semiquantitative way. The performance of conventional laboratory equipment and synchrotron radiation experimental setup are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281317700011 Publication Date 2010-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.455 Times cited 12 Open Access
Notes ; This work was performed with the support of the Fondazione Cassa di Risparmio di Torino, who founded the postgraduate internship of Eleonora Pellizzi at the CRCC (Master dei talenti). It received the technical support of the SMIS line of the SOLEIL synchrotron (Saint Aubin, France). We are thankful to all our colleagues who helped us during our experiments: Anne Laurence Dupont for providing gelatine samples, Chakib Djediat (Museum National d'Histoire Naturelle, Paris) for his advice regarding the samples preparation, Christophe Sandt (Synchrotron SOLEIL) for his help and availability during our Beam time allocation, and Paul Dumas (Synchrotron SOLEIL) for his warm reception on the SMIS line. ; Approved Most recent IF: 1.455; 2010 IF: 1.765
Call Number UA @ admin @ c:irua:84579 Serial 5627
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Author de Baere, K.; Verstraelen, H.; Dewil, R.; Lemmens, L.; Lenaerts, S.; Nkunzimana, T.; Potters, G.
Title Impact of tank construction on corrosion of ship ballast tanks Type A1 Journal article
Year (up) 2010 Publication Materials performance Abbreviated Journal Mater Performance
Volume 49 Issue 5 Pages 48-54
Keywords A1 Journal article; Theory of quantum systems and complex systems; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-1492 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.149 Times cited Open Access
Notes ; ; Approved Most recent IF: 0.149; 2010 IF: 0.055
Call Number UA @ admin @ c:irua:82385 Serial 5961
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Author Roet, D.; van Espen, P.
Title Monte Carlo simulation of X-ray spectra from low energy electrons using optical data Type A1 Journal article
Year (up) 2010 Publication Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms Abbreviated Journal
Volume 268 Issue 17/18 Pages 2794-2800
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract An approach using optical data to simulate both the bremsstrahlung continuum and characteristic K and L X-ray lines generated by low energy electrons (cfr. electron microscopy) in solids is discussed in this paper. The necessary analytical expressions together with the data to calculate the relevant cross sections for elastic and inelastic interactions at these energies along with variance reduction techniques are given. The results of the Monte Carlo simulation are compared to experimental data measured with a JEOL 6300 electron microscope.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281498900039 Publication Date 2010-07-15
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:84261 Serial 8281
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Author Damla, N.; Čevik, U.; Kobya, A.I.; Celik, A.; Celik, N.; Van Grieken, R.
Title Radiation dose estimation and mass attenuation coefficients of cement samples used in Turkey Type A1 Journal article
Year (up) 2010 Publication Journal of hazardous materials Abbreviated Journal
Volume 176 Issue 1/3 Pages 644-649
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Different cement samples commonly used in building construction in Turkey have been analyzed for natural radioactivity using gamma-ray spectrometry. The mean activity concentrations observed in the cement samples were 52, 40 and 324 Bq kg−1 for 226Ra, 232Th and 40K, respectively. The measured activity concentrations for these radionuclides were compared with the reported data of other countries and world average limits. The radiological hazard parameters such as radium equivalent activities (Raeq), gamma index (Iγ) and alpha index (Iα) indices as well as terrestrial absorbed dose and annual effective dose rate were calculated and compared with the international data. The Raeq values of cement are lower than the limit of 370 Bq kg−1, equivalent to a gamma dose of 1.5 mSv y−1. Moreover, the mass attenuation coefficients were determined experimentally and calculated theoretically using XCOM in some cement samples. Also, chemical compositions analyses of the cement samples were investigated.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000274839700087 Publication Date 2009-11-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3894 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:80671 Serial 8448
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Author Abakumov, A.M.; Batuk, D.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Tsirlin, A.A.; Niermann, D.; Waschowski, F.; Hemberger, J.; Van Tendeloo, G.; Antipov, E.V.
Title Antiferroelectric (Pb,Bi)1-xFe1+xO3-y perovskites modulated by crystallographic shear planes Type A1 Journal article
Year (up) 2011 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 23 Issue 2 Pages 255-265
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We demonstrate for the first time a possibility to vary the anion content in perovskites over a wide range through a long-range-ordered arrangement of crystallographic shear (CS) planes. Anion-deficient perovskites (Pb,Bi)1−xFe1+xO3−y with incommensurately modulated structures were prepared as single phases in the compositional range from Pb0.857Bi0.094Fe1.049O2.572 to Pb0.409Bi0.567Fe1.025O2.796. Using a combination of electron diffraction and high-resolution scanning transmission electron microscopy, we constructed a superspace model describing a periodic arrangement of the CS planes. The model was verified by refinement of the Pb0.64Bi0.32Fe1.04O2.675 crystal structure from neutron powder diffraction data ((3 + 1)D S.G. X2/m(α0γ), X = [1/2,1/2,1/2,1/2], a = 3.9082(1) Å, b = 3.90333(8) Å, c = 4.0900(1) Å, β = 91.936(2)°, q = 0.05013(4)a* + 0.09170(3)c* at T = 700 K, RP = 0.036, RwP = 0.048). The (Pb,Bi)1−xFe1+xO3−y structures consist of perovskite blocks separated by CS planes confined to nearly the (509)p perovskite plane. Along the CS planes, the perovskite blocks are shifted with respect to each other over the 1/2[110]p vector that transforms the corner-sharing connectivity of the FeO6 octahedra in the perovskite framework to an edge-sharing connectivity of the FeO5 pyramids at the CS plane, thus reducing the oxygen content. Variation of the chemical composition in the (Pb,Bi)1−xFe1+xO3−y series occurs mainly because of a changing thickness of the perovskite block between the interfaces, that can be expressed through the components of the q vector as Pb6γ+2αBi1−7γ−αFe1+γ−αO3−3γ−α. The Pb, Bi, and Fe atoms are subjected to strong displacements occurring in antiparallel directions on both sides of the perovskite blocks, resulting in an antiferroelectric-type structure. This is corroborated by the temperature-, frequency-, and field-dependent complex permittivity measurements. Pb0.64Bi0.32Fe1.04O2.675 demonstrates a remarkably high resistivity >0.1 T Ω cm at room temperature and orders antiferromagnetically below TN = 608(10) K.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000286160800018 Publication Date 2010-12-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 29 Open Access
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number UA @ lucian @ c:irua:88651 Serial 136
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Author Matulis, A.; Masir, M.R.; Peeters, F.M.
Title Application of optical beams to electrons in graphene Type A1 Journal article
Year (up) 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 83 Issue 11 Pages 115458-115458,7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The technique of beam optics is applied to the description of the wave function of Dirac electrons. This approach is illustrated by considering electron transmission through simple nonhomogeneous structures, such as flat and bent p-n junctions and superlattices. We found that a convex p-n junction compresses the beam waist, while a concave interface widens it without loosing its focusing properties. At a flat p-n junction the waist of the transmitted Gaussian beam can be narrowed or widened, depending on the angle of incidence. A general condition is derived for the occurrence of beam collimation in a superlattice which is less stringent than previous discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000288896400013 Publication Date 2011-03-29
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 13 Open Access
Notes ; This research was supported by the Flemish Science Foundation (Grant No. FWO-Vl), by the Belgian Science policy (IAP), and (in part) by the Lithuanian Science Council under project No. MIP-79/2010. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:89377 Serial 142
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Author Belik, A.A.; Abakumov, A.M.; Tsirlin, A.A.; Hadermann, J.; Kim, J.; Van Tendeloo, G.; Takayama-Muromachi, E.
Title Article Structure and magnetic properties of BiFe0.75Mn0.25O3 perovskite prepared at ambient and high pressure Type A1 Journal article
Year (up) 2011 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 23 Issue 20 Pages 4505-4514
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Solid solutions of BiFe1xMnxO3 (0.0 ≤ x ≤ 0.4) were prepared at ambient pressure and at 6 GPa. The ambient-pressure (AP) phases crystallize in space group R3c similarly to BiFeO3. The high-pressure (HP) phases crystallize in space group R3c for x = 0.05 and in space group Pnma for 0.15 ≤ x ≤ 0.4. The structure of HP-BiFe0.75Mn0.25O3 was investigated using synchrotron X-ray powder diffraction, electron diffraction, and transmission electron microscopy. HP-BiFe0.75Mn0.25O3 has a PbZrO3-related √2ap × 4ap × 2√2ap (ap is the parameter of the cubic perovskite subcell) superstructure with a = 5.60125(9) Å, b = 15.6610(2) Å, and c = 11.2515(2) Å similar to that of Bi0.82La0.18FeO3. A remarkable feature of this structure is the unconventional octahedral tilt system, with the primary ab0a tilt superimposed on pairwise clockwise and counterclockwise rotations around the b-axis according to the oioi sequence (o stands for out-of-phase tilt, and i stands for in-phase tilt). The (FeMn)O6 octahedra are distorted, with one longer metaloxygen bond (2.222.23 Å) that can be attributed to a compensation for covalent BiO bonding. Such bonding results in the localization of the lone electron pair on Bi3+ cations, as confirmed by electron localization function analysis. The relationship between HP-BiFe0.75Mn0.25O3 and antiferroelectric structures of PbZrO3 and NaNbO3 is discussed. On heating in air, HP-BiFe0.75Mn0.25O3 irreversibly transforms to AP-BiFe0.75Mn0.25O3 starting from about 600 K. Both AP and HP phases undergo an antiferromagnetic ordering at TN ≈ 485 and 520 K, respectively, and develop a weak net magnetic moment at low temperatures. Additionally, ceramic samples of AP-BiFe0.75Mn0.25O3 show a peculiar phenomenon of magnetization reversal.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000295897400015 Publication Date 2011-09-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 57 Open Access
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number UA @ lucian @ c:irua:93581 Serial 151
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Author Bittencourt, C.; Navio, C.; Nicolay, A.; Ruelle, B.; Godfroid, T.; Snyders, R.; Colomer, J.-F.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Suarez-Martinez, I.; Ewels, C.P.
Title Atomic oxygen functionalization of vertically aligned carbon nanotubes Type A1 Journal article
Year (up) 2011 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 115 Issue 42 Pages 20412-20418
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Vertically aligned multiwalled carbon nanotubes (v-MWCNTs) are functionalized using atomic oxygen generated in a microwave plasma. X-ray photoelectron spectroscopy depth profile analysis shows that the plasma treatment effectively grafts oxygen exclusively at the v-MWCNT tips. Electron microscopy shows that neither the vertical alignment nor the structure of v-MWCNTs were affected by the plasma treatment. Density functional calculations suggest assignment of XPS C 1s peaks at 286.6 and 287.5 eV, to epoxy and carbonyl functional groups, respectively.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000296205600009 Publication Date 2011-10-04
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 31 Open Access
Notes Iap Approved Most recent IF: 4.536; 2011 IF: 4.805
Call Number UA @ lucian @ c:irua:91890 Serial 174
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Author Khalilov, U.; Neyts, E.C.; Pourtois, G.; van Duin, A.C.T.
Title Can we control the thickness of ultrathin silica layers by hyperthermal silicon oxidation at room temperature? Type A1 Journal article
Year (up) 2011 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 115 Issue 50 Pages 24839-24848
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Using reactive molecular dynamics simulations by means of the ReaxFF potential, we studied the growth mechanism of ultrathin silica (SiO2) layers during hyperthermal oxidation at room temperature. Oxidation of Si(100){2 × 1} surfaces by both atomic and molecular oxygen was investigated in the energy range 15 eV. The oxidation mechanism, which differs from thermal oxidation, is discussed. In the case of oxidation by molecular O2, silica is quickly formed and the thickness of the formed layers remains limited compared to oxidation by atomic oxygen. The Si/SiO2 interfaces are analyzed in terms of partial charges and angle distributions. The obtained structures of the ultrathin SiO2 films are amorphous, including some intrinsic defects. This study is important for the fabrication of silica-based devices in the micro- and nanoelectronics industry, and more specifically for the fabrication of metal oxide semiconductor devices.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000297947700050 Publication Date 2011-11-16
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 36 Open Access
Notes Approved Most recent IF: 4.536; 2011 IF: 4.805
Call Number UA @ lucian @ c:irua:94303 Serial 273
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Author Zarenia, M.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.
Title Chiral states in bilayer graphene : magnetic field dependence and gap opening Type A1 Journal article
Year (up) 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 12 Pages 125451-125451,13
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract At the interface of electrostatic potential kink profiles, one-dimensional chiral states are found in bilayer graphene (BLG). Such structures can be created by applying an asymmetric potential to the upper and the lower layers of BLG. We found the following: (i) due to the strong confinement by the single kink profile, the unidirectional states are only weakly affected by a magnetic field; (ii) increasing the smoothness of the kink potential results in additional bound states, which are topologically different from those chiral states; and (iii) in the presence of a kink-antikink potential, the overlap between the oppositely moving chiral states results in the appearance of crossing and anticrossing points in the energy spectrum. This leads to the opening of tunable minigaps in the spectrum of the unidirectional topological states.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000295484300016 Publication Date 2011-09-30
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 50 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CONGRAN), the Brazilian agency CNPq (Pronex), and the bilateral projects between Flanders and Brazil and the collaboration project FWO-CNPq. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:92915 Serial 358
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Author Verleysen, E.; Bender, H.; Richard, O.; Schryvers, D.; Vandervorst, W.
Title Compositional characterization of nickel silicides by HAADF-STEM imaging Type A1 Journal article
Year (up) 2011 Publication Journal of materials science Abbreviated Journal J Mater Sci
Volume 46 Issue 7 Pages 2001-2008
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A methodology for the quantitative compositional characterization of nickel silicides by high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) imaging is presented. HAADF-STEM images of a set of nickel silicide reference samples Ni3Si, Ni31Si12, Ni2Si, NiSi and NiSi2 are taken at identical experimental conditions. The correlation between sample thickness and HAADF-STEM intensity is discussed. In order to quantify the relationship between the experimental Z-contrast intensities and the composition of the analysed layers, the ratio of the HAADF-STEM intensity to the sample thickness or to the intensity of the silicon substrate is determined for each nickel silicide reference sample. Diffraction contrast is still detected on the HAADF-STEM images, even though the detector is set at the largest possible detection angle. The influence on the quantification results of intensity fluctuations caused by diffraction contrast and channelling is examined. The methodology is applied to FUSI gate devices and to horizontal TFET devices with different nickel silicides formed on source, gate and drain. It is shown that, if the elements which are present are known, this methodology allows a fast quantitative 2-dimensional compositional analysis.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000286633000002 Publication Date 2011-01-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2461;1573-4803; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.599 Times cited 1 Open Access
Notes Approved Most recent IF: 2.599; 2011 IF: 2.015
Call Number UA @ lucian @ c:irua:88950 Serial 446
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Author Chaves, A.; Komendová, L.; Milošević, M.V.; Andrade, J.S.; Farias, G.A.; Peeters, F.M.
Title Conditions for nonmonotonic vortex interaction in two-band superconductors Type A1 Journal article
Year (up) 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 83 Issue 21 Pages 214523-214523,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We describe a semianalytic approach to the two-band Ginzburg-Landau theory, which predicts the behavior of vortices in two-band superconductors. We show that the character of the short-range vortex-vortex interaction is determined by the sign of the normal domain-superconductor interface energy, in analogy with the conventional differentiation between type I and type II superconductors. However, we also show that the long-range interaction is determined by a modified Ginzburg-Landau parameter κ*, different from the standard κ of a bulk superconductor. This opens the possibility for nonmonotonic vortex-vortex interaction, which is temperature dependent, and can be further tuned by alterations of the material on the microscopic scale.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000292252300009 Publication Date 2011-06-30
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 46 Open Access
Notes ; Discussions with A. Moreira, A. Shanenko, R. Prozorov, and A. Golubov are gratefully acknowledged. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the bilateral project FWO-CNPq, CAPES, and PRONEX/CNPq/FUNCAP. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:90922 Serial 477
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Author Peelaers, H.; Partoens, B.; Giantomassi, M.; Rangel, T.; Goossens, E.; Rignanese, G.-M.; Gonze, X.; Peeters, F.M.
Title Convergence of quasiparticle band structures of Si and Ge nanowires in the GW approximation and the validity of scissor shifts Type A1 Journal article
Year (up) 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 83 Issue 4 Pages 045306-045306,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Starting from fully converged density-functional theory calculations, the quasiparticle corrections are calculated for different sized Si and Ge nanowires using the GW approximation. The effectiveness of recently developed techniques in speeding up the convergence of the quasiparticle calculations is demonstrated. The complete quasiparticle band structures are also obtained using an interpolation technique based on maximallylocalized Wannier functions. From the quasiparticle results, we assess the correctness of the commonly applied scissor-shift correction. Dispersion changes are observed, which are also reflected in changes in the effective band masses calculated taking into account quasiparticle corrections.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000286771400004 Publication Date 2011-01-21
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 ; We are grateful to Yann Pouillon for valuable technical support with the build system of ABINIT, related to the WANNIER90 library. This work was supported by the Flemish Science Foundation (FWO-Vl) and by the Interuniversity Attraction Poles Program (P6/42)-Belgian State-Belgian Science Policy. X. G. and G.-M. R. acknowledge funding from the EU's 7th Framework Programme through the ETSF I3 e-Infrastructure project (Grant No. 211956), the Communaute francaise de Belgique through the Action de Recherche Concertee 07/12-003 “Nanosystemes hybrides metal-organiques,” and the Wallon Region Project No. 816849 “ European Theoretical Spectroscopy Facility” (WALL ETSF). M. G. acknowledges funding from the FRFC Project No. 2.4.589.09.F. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:86905 Serial 510
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Author Klimczuk, T.; Wang, C.H.; Lawrence, J.M.; Xu, Q.; Durakiewicz, T.; Ronning, F.; Llobet, A.; Trouw, F.; Kurita, N.; Tokiwa, Y.; Lee, H.o.; Booth, C.H.; Gardner, J.S.; Bauer, E.D.; Joyce, J.J.; Zandbergen, H.W.; Movshovich, R.; Cava, R.J.; Thompson, J.D.;
Title Crystal fields, disorder, and antiferromagnetic short-range order in Yb0.24Sn0.76Ru Type A1 Journal article
Year (up) 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 7 Pages 075152-075152,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report extensive measurements on a new compound (Yb0.24Sn0.76)Ru that crystallizes in the cubic CsCl structure. Valence-band photoemission (PES) and L3 x-ray absorption show no divalent component in the 4f configuration of Yb. Inelastic neutron scattering (INS) indicates that the eight-fold degenerate J-multiplet of Yb3+ is split by the crystalline electric field (CEF) into a Γ7-doublet ground state and a Γ8 quartet at an excitation energy 20 meV. The magnetic susceptibility can be fit very well by this CEF scheme under the assumption that a Γ6-excited state resides at 32 meV; however, the Γ8/Γ6 transition expected at 12 meV was not observed in the INS. The resistivity follows a Bloch-Grüneisen law shunted by a parallel resistor, as is typical of systems subject to phonon scattering with no apparent magnetic scattering. All of these properties can be understood as representing simple local moment behavior of the trivalent Yb ion. At 1 K there is a peak in specific heat that is too broad to represent a magnetic-phase transition, consistent with absence of magnetic reflections in neutron diffraction. On the other hand this peak also is too narrow to represent the Kondo effect in the Γ7-doublet ground state. On the basis of the field dependence of the specific heat, we argue that antiferromagnetic (AF) short-range order (SRO) (possibly coexisting with Kondo physics) occurs at low temperatures. The long-range magnetic order is suppressed because the Yb site occupancy is below the percolation threshold for this disordered compound.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000293830800003 Publication Date 2011-08-15
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 8 Open Access
Notes Esteem 026019 Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:92427 Serial 555
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Author Komendová, L.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M.
Title Different length scales for order parameters in two-gap superconductors : extended Ginzburg-Landau theory Type A1 Journal article
Year (up) 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 6 Pages 064522-064522,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the Ginzburg-Landau theory extended to the next-to-leading order, we determine numerically the healing lengths of the two order parameters at the two-gap superconductor/normal metal interface. We demonstrate on several examples that those can be different even in the strict domain of applicability of the Ginzburg-Landau theory. This justifies the use of this theory to describe relevant physics of two-gap superconductors, distinguishing them from their single-gap counterparts. The calculational degree of complexity increases only slightly with respect to the conventional Ginzburg-Landau expansion, thus the extended Ginzburg-Landau model remains numerically far less demanding compared to the full microscopic approaches.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000294226000013 Publication Date 2011-08-25
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 56 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:92414 Serial 695
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Author Peirs, J.; Verleysen, P.; Tirry, W.; Rabet, L.; Schryvers, D.; Degrieck, J.
Title Dynamic shear localization in Ti6Al4V Type P1 Proceeding
Year (up) 2011 Publication Procedia Engineering T2 – 11th International Conference on the Mechanical Behavior of Materials, (ICM), 2011, Como, ITALY (ICM11) Abbreviated Journal
Volume Issue Pages 1-6
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract The alloy Ti6Al4V is known to be prone to the formation of adiabatic shear bands when dynamically loaded in shear. This causes a catastrophic decrease of the load carrying capacity and is usually followed by fracture. Although, the main mechanism is recognized to be the competition between strain hardening and thermal softening, a detailed understanding of the role of microstructural plasticity mechanisms and macroscopic loading conditions does not exist yet. To study strain localization and shear fracture, different high strain rate shear tests have been carried out: compression of hat-shaped specimens, torsion of thin walled tubular specimens and in-plane shear tests. The value of the three techniques in studying shear localization is evaluated. Post-mortem analysis of the fracture surface and the materials' microstructure is performed with optical and electron microscopy. In all cases a ductile fracture is observed. SEM and TEM techniques are used to study the local microstructure and composition in the shear band and as such the driving mechanism for the ASB formation. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of ICM11
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000300451302060 Publication Date 2011-06-20
Series Editor Series Title Abbreviated Series Title
Series Volume 10 Series Issue Edition
ISSN 1877-7058; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 4 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113069 Serial 767
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Author Sofo, J.O.; Suarez, A.M.; Usaj, G.; Cornaglia, P.S.; Hernández-Nieves, A.D.; Balseiro, C.A.
Title Electrical control of the chemical bonding of fluorine on graphene Type A1 Journal article
Year (up) 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 83 Issue 8 Pages 081411
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the electronic structure of diluted F atoms chemisorbed on graphene using density functional theory calculations. We show that the nature of the chemical bonding of a F atom adsorbed on top of a C atom in graphene strongly depends on carrier doping. In neutral samples the F impurities induce a sp(3)-like bonding of the C atom below, generating a local distortion of the hexagonal lattice. As the graphene is electron-doped, the C atom retracts back to the graphene plane and for high doping (10(14) cm(-2)) its electronic structure corresponds to a nearly pure sp(2) configuration. We interpret this sp(3)-sp(2) doping-induced crossover in terms of a simple tight-binding model and discuss the physical consequences of this change.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000287484800005 Publication Date 2011-02-18
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 65 Open Access
Notes ; J.O.S. and A. S. acknowledge support from the Donors of the American Chemical Society Petroleum Research Fund and use of facilities at the Penn State Materials Simulation Center. G. U., P. S. C., A. D. H., and C. A. B. acknowledge financial support from PICTs 06-483 and 2008-2236 from ANPCyT and PIP 11220080101821 from CONICET, Argentina. A. D. H. acknowledges support from the Flemish Science Foundation (FWO). ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:105600 Serial 892
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