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Author Berdiyorov, G.R.; Milošević, M.V.; Latimer, M.L.; Xiao, Z.L.; Kwok, W.K.; Peeters, F.M.
Title Large magnetoresistance oscillations in mesoscopic superconductors due to current-excited moving vortices Type A1 Journal article
Year 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 109 Issue 5 Pages 057004
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We show in the case of a superconducting Nb ladder that a mesoscopic superconductor typically exhibits magnetoresistance oscillations whose amplitude and temperature dependence are different from those stemming from the Little-Parks effect. We demonstrate that these large resistance oscillations (as well as the monotonic background on which they are superimposed) are due to current-excited moving vortices, where the applied current in competition with the oscillating Meissner currents imposes or removes the barriers for vortex motion in an increasing magnetic field. Because of the ever present current in transport measurements, this effect should be considered in parallel with the Little-Parks effect in low-critical temperature (T-c) samples, as well as with recently proposed thermal activation of dissipative vortex-antivortex pairs in high-T-c samples.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos (up) 000306994900024 Publication Date 2012-07-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 65 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP) (theory) and by the U. S. Department of Energy (DOE) Award No. DE-FG02-06ER46334 (experiment). G. R. B. acknowledges individual grant from FWO-Vl. W. K. K. acknowledges support from DOE BES under Contract No. DE-AC02-06CH11357, which also funds Argonne's Center for Nanoscale Materials (CNM) where the focused-ion-beam milling was performed. ; Approved Most recent IF: 8.462; 2012 IF: 7.943
Call Number UA @ lucian @ c:irua:100832 Serial 1780
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Author Napolsky, P.S.; Drozhzhin, O.A.; Istomin, S.Y.; Kazakov, S.M.; Antipov, E.V.; Galeeva, A.V.; Gippius, A.A.; Svensson, G.; Abakumov, A.M.; Van Tendeloo, G.
Title Structure and high-temperature properties of the (Sr,Ca,Y)(Co,Mn)O3-y perovskites – perspective cathode materials for IT-SOFC Type A1 Journal article
Year 2012 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 192 Issue Pages 186-194
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Oxygen deficient perovskites Sr0.75Y0.25Co1-xMnxO3-y, x=0.5 and 0.75, were prepared by using the citrate route at 1373-1573 K for 48 h. The cubic Pm-3m perovskite structure for x=0.5 was confirmed by electron diffraction study and refined using neutron powder diffraction (NPD) data. For x=0.75, the superstructure corresponding to a=root 2 x a(per), b=2 x a(per), c=root 2 x a(per) (a(0)b(-)b(-) tilt system, space group Imma) was revealed by electron diffraction. The solid solution Sr0.75-xCaxY0.25Co0.25Mn0.75O3-y, 0.1 <= x <= 0.6 and compound Ca0.75Y0.25Mn0.85Co0.15O2.92 were prepared in air at 1573 K for 48 h. The crystal structure of Ca0.75Y0.25Mn0.85Co0.15O2.92 was refined using NPD data (S.G. Pnma, a=5.36595(4), b=7.5091(6), c=5.2992(4) angstrom, R-p=0.057, R-wp=0.056, chi(2)=4.26). High-temperature thermal expansion properties of the prepared compounds were studied in air using both dilatometry and high-temperature X-ray powder diffraction data (HTXRPD). They expanding non-linearly at 298-1073 K due to the loss of oxygen at high temperatures. Calculated average thermal expansion coefficients (TECs) for Sr0.75Y0.25Co1-xMnxO3-y, x=0.5, 0.75 and Ca0.75Y0.25Mn0.85Co0.15O2.92(1) are 15.5, 15.1, and 13.8 ppm K-1, respectively. Anisotropy of the thermal expansion along different unit cell axes was observed for Sr0.15Ca0.6Y0.25Co0.25Mn0.75O3-y, and Ca0.75Y0.25Mn0.85Co0.15O2.92. Conductivity of Sr0.75Y0.25Co1-xMnxO3-y, x=0.5 and 0.75 increases with the temperature reaching 110 S/cm for x=0.5 and 44 S/cm for x=0.75 at 1173 K. Samples of Sr0.75-xCaxY0.25Co0.25Mn0.75O3-y, 0.1 <= y <= 0.6 were found to be n-type conductors at room temperature with the similar temperature dependence of the conductivity and demonstrated the increase of the sigma value from similar to 1 to similar to 50 S/cm as the temperature increases from 300 to 1173 K. Their conductivity is described in terms of the small polaron charge transport with the activation energy (E-p) increasing from 340 to 430 meV with an increase of the calcium content from x=0 to x=0.6. (C) 2012 Elsevier Inc. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000307028300030 Publication Date 2012-03-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 5 Open Access
Notes Approved Most recent IF: 2.299; 2012 IF: 2.040
Call Number UA @ lucian @ c:irua:101119 Serial 3279
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Author Yusupov, M.; Saraiva, M.; Depla, D.; Bogaerts, A.
Title Sputter deposition of MgxAlyOz thin films in a dual-magnetron device : a multi-species Monte Carlo model Type A1 Journal article
Year 2012 Publication New journal of physics Abbreviated Journal New J Phys
Volume 14 Issue 7 Pages 073043
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A multi-species Monte Carlo (MC) model, combined with an analytical surface model, has been developed in order to investigate the general plasma processes occurring during the sputter deposition of complex oxide films in a dual-magnetron sputter deposition system. The important plasma species, such as electrons, Ar+ ions, fast Ar atoms and sputtered metal atoms (i.e. Mg and Al atoms) are described with the so-called multi-species MC model, whereas the deposition of MgxAlyOz films is treated by an analytical surface model. Targetsubstrate distances for both magnetrons in the dual-magnetron setup are varied for the purpose of growing stoichiometric complex oxide thin films. The metal atoms are sputtered from pure metallic targets, whereas the oxygen flux is only directed toward the substrate and is high enough to obtain fully oxidized thin films but low enough to avoid target poisoning. The calculations correspond to typical experimental conditions applied to grow these complex oxide films. In this paper, some calculation results are shown, such as the densities of various plasma species, their fluxes toward the targets and substrate, the deposition rates, as well as the film stoichiometry. Moreover, some results of the combined model are compared with experimental observations. Note that this is the first complete model, which can be applied for large and complicated magnetron reactor geometries, such as dual-magnetron configurations. With this model, we are able to describe all important plasma species as well as the deposition process. It can also be used to predict film stoichiometries of complex oxide films on the substrate.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos (up) 000307072500003 Publication Date 2012-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.786 Times cited 2 Open Access
Notes Approved Most recent IF: 3.786; 2012 IF: 4.063
Call Number UA @ lucian @ c:irua:100100 Serial 3111
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Author Grzelczak, M.; Sánchez-Iglesias, A.; Heidari Mezerji, H.; Bals, S.; Pérez-Juste, J.; Liz-Marzán, L.M.
Title Steric hindrance induces crosslike self-assembly of gold nanodumbbells Type A1 Journal article
Year 2012 Publication Nano letters Abbreviated Journal Nano Lett
Volume 12 Issue 8 Pages 4380-4384
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In the formation of colloidal molecules, directional interactions are crucial for controlling the spatial distribution of the building blocks. Anisotropic nanoparticles facilitate directional clustering via steric constraints imposed by each specific shape, thereby restricting assembly along certain directions. We show in this Letter that the combination of patchiness (attraction) and shape (steric hindrance) allows assembling gold nanodumbbell building blocks into crosslike dimers with well-controlled interparticle distance and relative orientation. Steric hindrance between interacting dumbbell-like particles opens up a new synthetic approach toward low-symmetry plasmonic clusters, which may significantly contribute to understand complex plasmonic phenomena.
Address
Corporate Author Thesis
Publisher Place of Publication Washington Editor
Language Wos (up) 000307211000081 Publication Date 2012-07-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 85 Open Access
Notes Nanodirect 213948-2; 262348 Esmi Approved Most recent IF: 12.712; 2012 IF: 13.025
Call Number UA @ lucian @ c:irua:101900 Serial 3161
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Author Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.
Title Cyclotron resonance of trilayer graphene Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 8 Pages 085412
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The cyclotron resonance energies, the corresponding oscillator strengths, and the cyclotron absorption spectrum for trilayer graphene are calculated for both ABA and ABC stacking. A gate potential across the stacked layers leads to (1) a reduction of the transition energies, (2) a lifting of the degeneracy of the zero Landau level, and (3) the removal of the electron-hole symmetry.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos (up) 000307273100009 Publication Date 2012-08-08
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 7 Open Access
Notes ; This work was supported by the National Council for the Improvement of Higher education (CAPES), the Brazilian Council for Research (CNPq), the Flemish Science Foundation (FWO-V1), the bilateral projects between Flanders and Brazil and the CNPq and FWO-V1, and the ESF-Eurographene project CONGRAN. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:100815 Serial 604
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Author Phung, Q.M.; Vancoillie, S.; Delabie, A.; Pourtois, G.; Pierloot, K.
Title Ruthenocene and cyclopentadienyl pyrrolyl ruthenium as precursors for ruthenium atomic layer deposition : a comparative study of dissociation enthalpies Type A1 Journal article
Year 2012 Publication Theoretical chemistry accounts : theory, computation, and modeling Abbreviated Journal Theor Chem Acc
Volume 131 Issue 7 Pages 1238
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract RuCp2 (ruthenocene) and RuCpPy (cyclopentadienyl pyrrolyl ruthenium) complexes are used in ruthenium (Ru) atomic layer deposition (ALD) but exhibit a markedly different reactivity with respect to the substrate and co-reactant. In search of an explanation, we report here the results of a comparative study of the heterolytic and homolytic dissociation enthalpy of these two ruthenium complexes, making use of either density functional theory (DFT) or multiconfigurational perturbation theory (CASPT2). While both methods predict distinctly different absolute dissociation enthalpies, they agree on the relative values between both molecules. A reduced heterolytic dissociation enthalpy is obtained for RuCpPy compared to RuCp2, although the difference obtained from CASPT2 (19.9 kcal/mol) is slightly larger than the one obtained with any of the DFT functionals (around 17 kcal/mol). Both methods also agree on the more pronounced stability of the Cp- ligand in RuCpPy than in RuCp2 (by around 9 kcal/mol with DFT and by 6 kcal/mol with CASPT2).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000307274300003 Publication Date 2012-07-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1432-881X;1432-2234; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.89 Times cited 5 Open Access
Notes Approved Most recent IF: 1.89; 2012 IF: 2.233
Call Number UA @ lucian @ c:irua:101139 Serial 2935
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Author Klingstedt, M.; Sundberg, M.; Eriksson, L.; Haigh, S.; Kirkland, A.; Grüner, D.; de Backer, A.; Van Aert, S.; Tarasaki, O.
Title Exit wave reconstruction from focal series of HRTEM images, single crystal XRD and total energy studies on SbxWO3+y (x\sim0.11) Type A1 Journal article
Year 2012 Publication Zeitschrift für Kristallographie Abbreviated Journal Z Krist-Cryst Mater
Volume 227 Issue 6 Pages 341-349
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new tungsten bronze in the SbWO system has been prepared in a solid state reaction from Sb2O3, WO3 and W metal powder. The average structure was determined by single crystal X-ray diffraction. SbxWO3+y (x ∼ 0.11) crystallizes in the orthorhombic space group Pm21n (no. 31), a = 27.8135(9) Å, b = 7.3659(2) Å and c = 3.8672(1) Å. The structure belongs to the (n)-ITB class of intergrowth tungsten bronzes. It contains slabs of hexagonal channels formed by six WO6 octahedra. These slabs are separated by three layers of WO6 octahedra that are arranged in a WO3-type fashion. The WO6 octahedra share all vertices to build up a three-dimensional framework. The hexagonal channels are filled with Sb atoms to ∼80% and additional O atoms. The atoms are shifted out of the center of the channels. Exit-wave reconstruction of focal series of high resolution-transmission-electron-microscope (HRTEM) images combined with statistical paramäeter estimation techniques allowed to study local ordering in the channels. Sb atoms in neighbouring channels tend to be displaced in the same direction, which is in agreement with total energy calculations on ordered structure models, but the ratio of the occupation of the two possible Sb sites varies from channel to channel. The structure of SbxWO3+y exhibits pronounced local modulations.
Address
Corporate Author Thesis
Publisher Place of Publication München Editor
Language Wos (up) 000307314200003 Publication Date 2012-06-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2194-4946; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.179 Times cited 4 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 3.179; 2012 IF: NA
Call Number UA @ lucian @ c:irua:101218 Serial 1131
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Author Gengler, R.Y.N.; Toma, L.M.; Pardo, E.; Lloret, F.; Ke, X.; Van Tendeloo, G.; Gournis, D.; Rudolf, P.
Title Prussian blue analogues of reduced dimensionality Type A1 Journal article
Year 2012 Publication Small Abbreviated Journal Small
Volume 8 Issue 16 Pages 2532-2540
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Mixed-valence polycyanides (Prussian Blue analogues) possess a rich palette of properties spanning from room-temperature ferromagnetism to zero thermal expansion, which can be tuned by chemical modifications or the application of external stimuli (temperature, pressure, light irradiation). While molecule-based materials can combine physical and chemical properties associated with molecular-scale building blocks, their successful integration into real devices depends primarily on higher-order properties such as crystal size, shape, morphology, and organization. Herein a study of a new reduced-dimensionality system based on Prussian Blue analogues (PBAs) is presented. The system is built up by means of a modified Langmuir-Blodgett technique, where the PBA is synthesized from precursors in a self-limited reaction on a clay mineral surface. The focus of this work is understanding the magnetic properties of the PBAs in different periodic, low-dimensional arrangements, and the influence of the “on surface” synthesis on the final properties and dimensionality of the system.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos (up) 000307390300012 Publication Date 2012-07-03
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 17 Open Access
Notes Approved Most recent IF: 8.643; 2012 IF: 7.823
Call Number UA @ lucian @ c:irua:101104 Serial 2736
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Author Wang, B.; Idrissi, H.; Galceran, M.; Colla, M.S.; Turner, S.; Hui, S.; Raskin, J.P.; Pardoen, T.; Godet, S.; Schryvers, D.
Title Advanced TEM investigation of the plasticity mechanisms in nanocrystalline freestanding palladium films with nanoscale twins Type A1 Journal article
Year 2012 Publication International journal of plasticity Abbreviated Journal Int J Plasticity
Volume 37 Issue Pages 140-156
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Nanocrystalline palladium thin films deposited by electron-beam evaporation and deformed by on-chip tensile testing reveal a surprisingly large strain hardening capacity when considering the small similar to 25 nm grain size. The as-grown films contain several coherent single and multifold twin boundaries. The coherency of the twin boundaries considerably decreases with deformation due to dislocation/twin boundary interactions. These reactions are described based on a detailed analysis of the number and the type of dislocations located at the twin boundaries using high-resolution TEM, including aberration corrected microscopy. Sessile Frank dislocations were observed at the twin/matrix interfaces, explaining the loss of the TB coherency due to the Burgers vector pointing out of the twinning plane. Grain boundary mediated processes were excluded as a mechanism dominating the plastic deformation based on the investigation of the grain size distribution as well as the crystallographic texture using Automated Crystallographic Orientation Indexation TEM. Other factors influencing the plastic deformation such as impurities and the presence of a native passivation oxide layer at the surface of the films were investigated using analytical TEM. The twin boundaries observed in the present work partly explain the high strain hardening capacity by providing both increasing resistance to dislocation motion with deformation and a source for dislocation multiplication. (C) 2012 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos (up) 000307416100009 Publication Date 2012-05-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0749-6419; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.702 Times cited 44 Open Access
Notes Iap; Fwo Approved Most recent IF: 5.702; 2012 IF: 4.356
Call Number UA @ lucian @ c:irua:101082 Serial 74
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Author Quintana, M.; Grzelczak, M.; Spyrou, K.; Calvaresi, M.; Bals, S.; Kooi, B.; Van Tendeloo, G.; Rudolf, P.; Zerbetto, F.; Prato, M.
Title A simple road for the transformation of few-layer graphene into MWNTs Type A1 Journal article
Year 2012 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 134 Issue 32 Pages 13310-13315
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report the direct formation of multiwalled carbon nanotubes (MWNT) by ultrasonication of graphite in dimethylformamide (DMF) upon addition of ferrocene aldehyde (Fc-CHO). The tubular structures appear exclusively at the edges of graphene layers and contain Fe clusters. Pc in conjunction with benzyl aldehyde, or other Fc derivatives, does not induce formation of NT. Higher amounts of Fc-CHO added to the dispersion do not increase significantly MWNT formation. Increasing the temperature reduces the amount of formation of MWNTs and shows the key role of ultrasound-induced cavitation energy. It is concluded that Fc-CHO first reduces the concentration of radical reactive species that slice graphene into small moieties, localizes itself at the edges of graphene, templates the rolling up of a sheet to form a nanoscroll, where it remains trapped, and finally accepts and donates unpaired electron to the graphene edges and converts the less stable scroll into a MWNT. This new methodology matches the long held notion that CNTs are rolled up graphene layers. The proposed mechanism is general and will lead to control the production of carbon nanostructures by simple ultrasonication treatments.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000307487200034 Publication Date 2012-05-08
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 This work was supported by the University of Trieste, the Italian Ministry of Education MIUR (cofin Prot. 20085M27SS), the European Union through the ERC grant No. 246791 – COUNTATOMS, the grant agreement for an Integrated Infrastructure Initiative N. 262348 ESMI, and the “Graphene-based electronics” research program of the Foundation for Fundamental Research on Matter (FOM). Approved Most recent IF: 13.858; 2012 IF: 10.677
Call Number UA @ lucian @ c:irua:101109 Serial 3003
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Author Charkin, D.O.; Urmanov, A.V.; Kazakov, S.M.; Batuk, D.; Abakumov, A.M.; Knöner, S.; Gati, E.; Wolf, B.; Lang, M.; Shevelkov, A.V.; Van Tendeloo, G.; Antipov, E.V.;
Title Synthesis, crystal structure, transport, and magnetic properties of novel ternary copper phosphides, A2Cu6P5(A = Sr, Eu) and EuCu4P3 Type A1 Journal article
Year 2012 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 51 Issue 16 Pages 8948-8955
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Three new ternary copper phosphides, Sr2Cu6P5, Eu2Cu6P5, and EuCu4P3, have been synthesized from the elements in evacuated silica capsules. Eu2Cu6P5 and Sr2Cu6P5 adopt the Ca2Cu6P5-type structure, while EuCu4P3 is isostructural to BaMg4Si3 and still remains the only representative of this structure type among the ternary Cu pnictides. All three materials show metallic conductivity in the temperature range 2 K <= T <= 290 K, with no indication for superconductivity. For Eu2Cu6P5 and EuCu4P3, long-range magnetic order was observed, governed by 4f local moments on the Eu atoms with predominant ferromagnetic interactions. While Eu2Cu6P5 shows a single ferromagnetic transition at T-C = 34 K, the magnetic behavior of EuCu4P3 is more complex, giving rise to three consecutive magnetic phase transitions at 70, 43, and 18 K.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos (up) 000307606200042 Publication Date 2012-07-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 13 Open Access
Notes Approved Most recent IF: 4.857; 2012 IF: 4.593
Call Number UA @ lucian @ c:irua:102217 Serial 3453
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Author Kalidindi, S.B.; Hyunchul, O.; Hirscher, M.; Esken, D.; Wiktor, C.; Turner, S.; Van Tendeloo, G.; Fischer, R.A.
Title Metal@COFs : covalent organic frameworks as templates for Pd nanoparticles and hydrogen storage properties of Pd@COF-102 hybrid material Type A1 Journal article
Year 2012 Publication Chemistry: a European journal Abbreviated Journal Chem-Eur J
Volume 18 Issue 35 Pages 10848-10856
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Three-dimensional covalent organic frameworks (COFs) have been demonstrated as a new class of templates for nanoparticles. Photodecomposition of the [Pd(eta 3-C3H5)(eta 5-C5H5)]@COF-102 inclusion compound (synthesized by a gas-phase infiltration method) led to the formation of the Pd@COF-102 hybrid material. Advanced electron microscopy techniques (including high-angle annular dark-field scanning transmission electron microscopy and electron tomography) along with other conventional characterization techniques unambiguously showed that highly monodisperse Pd nanoparticles ((2.4 +/- 0.5) nm) were evenly distributed inside the COF-102 framework. The Pd@COF-102 hybrid material is a rare example of a metal-nanoparticle-loaded porous crystalline material with a very narrow size distribution without any larger agglomerates even at high loadings (30 wt %). Two samples with moderate Pd content (3.5 and 9.5 wt %) were used to study the hydrogen storage properties of the metal-decorated COF surface. The uptakes at room temperature from these samples were higher than those of similar systems such as Pd@metalorganic frameworks (MOFs). The studies show that the H2 capacities were enhanced by a factor of 2-3 through Pd impregnation on COF-102 at room temperature and 20 bar. This remarkable enhancement is not just due to Pd hydride formation and can be mainly ascribed to hydrogenation of residual organic compounds, such as bicyclopentadiene. The significantly higher reversible hydrogen storage capacity that comes from decomposed products of the employed organometallic Pd precursor suggests that this discovery may be relevant to the discussion of the spillover phenomenon in metal/MOFs and related systems.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos (up) 000307782800013 Publication Date 2012-08-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.317 Times cited 88 Open Access
Notes Fwo Approved Most recent IF: 5.317; 2012 IF: 5.831
Call Number UA @ lucian @ c:irua:100469 Serial 2007
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Author Schattschneider, P.; Stoeger-Pollach, M.; Verbeeck, J.
Title Novel vortex generator and mode converter for electron beams Type A1 Journal article
Year 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 109 Issue 8 Pages 084801-1
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A mode converter for electron vortex beams is described. Numerical simulations, confirmed by experiment, show that the converter transforms a vortex beam with a topological charge m = +/- 1 into beams closely resembling Hermite-Gaussian HG(10) and HG(01) modes. The converter can be used as a mode discriminator or filter for electron vortex beams. Combining the converter with a phase plate turns a plane wave into modes with topological charge m = +/- 1. This combination serves as a generator of electron vortex beams of high brilliance.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos (up) 000307790900004 Publication Date 2012-08-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 74 Open Access
Notes Countatoms; Vortex ECASJO_; Approved Most recent IF: 8.462; 2012 IF: 7.943
Call Number UA @ lucian @ c:irua:101103UA @ admin @ c:irua:101103 Serial 2384
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Author Zarenia, M.; Leenaerts, O.; Partoens, B.; Peeters, F.M.
Title Substrate-induced chiral states in graphene Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 8 Pages 085451
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Unidirectional chiral states are predicted in single layer graphene which originate from the breaking of the sublattice symmetry due to an asymmetric mass potential. The latter can be created experimentally using boron-nitride (BN) substrates with a line defect (B-B or N-N) that changes the induced mass potential in graphene. Solving the Dirac-Weyl equation, the obtained energy spectrum is compared with the one calculated using ab initio density functional calculations. We found that these one-dimensional chiral states are very robust and they can even exist in the presence of a small gap between the mass regions. In the latter case additional bound states are found that are topologically different from those chiral states.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000308005600015 Publication Date 2012-08-28
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 41 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), and the European Science Foundation (ESF) under the EUROCORES Program: EuroGRAPHENE (project CONGRAN). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:101100 Serial 3347
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Author Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Rosner, H.
Title (CuCl)LaTa2O\text{7} and quantum phase transition in the (CuX)LaM2O7 family (X=Cl, Br; M=Nb, Ta) Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 6 Pages 064440-12
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We apply neutron diffraction, high-resolution synchrotron x-ray diffraction, magnetization measurements, electronic structure calculations, and quantum Monte-Carlo simulations to unravel the structure and magnetism of (CuCl)LaTa2O7. Despite the pseudo-tetragonal crystallographic unit cell, this compound features an orthorhombic superstructure, similar to the Nb-containing (CuX)LaNb2O7 with X = Cl and Br. The spin lattice entails dimers formed by the antiferromagnetic fourth-neighbor coupling J(4), as well as a large number of nonequivalent interdimer couplings quantified by an effective exchange parameter J(eff). In (CuCl)LaTa2O7, the interdimer couplings are sufficiently strong to induce the long-range magnetic order with the Neel temperature T-N similar or equal to 7 K and the ordered magnetic moment of 0.53 mu(B), as measured with neutron diffraction. This magnetic behavior can be accounted for by J(eff)/J(4) similar or equal to 1.6 and J(4) similar or equal to 16 K. We further propose a general magnetic phase diagram for the (CuCl)LaNb2O7-type compounds, and explain the transition from the gapped spin-singlet (dimer) ground state in (CuCl)LaNb2O7 to the long-range antiferromagnetic order in (CuCl)LaTa2O7 and (CuBr)LaNb2O7 by an increase in the magnitude of the interdimer couplings J(eff)/J(4), with the (CuCl)LaM2O7 (M = Nb, Ta) compounds lying on different sides of the quantum critical point that separates the singlet and long-range-ordered magnetic ground states.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000308127600006 Publication Date 2012-08-29
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 6 Open Access
Notes Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:101886 Serial 3526
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Author Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.; Costa Filho, R.N.
Title The electronic properties of graphene and graphene ribbons under simple shear strain Type A1 Journal article
Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 24 Issue 37 Pages 375301
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A tight-binding model is used to study the energy band of graphene and graphene ribbon under simple shear strain. The ribbon consists of lines of carbon atoms in an armchair or zigzag orientation where a simple shear strain is applied in the x-direction keeping the atomic distances in the y-direction unchanged. Such modification in the lattice gives an energy band that differs in several aspects from the one without any shear and with pure shear. The changes in the spectrum depend on the line displacement of the ribbon, and also on the modified hopping parameter. It is also shown that this simple shear strain tunes the electronic properties of both graphene and graphene ribbon, opening and closing energy gaps for different displacements of the system. The modified density of states is also shown.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000308202700011 Publication Date 2012-08-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 15 Open Access
Notes ; This work was supported by CNPq (RNCF), the National Council for the Improvement of Higher Education (CAPES), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the bilateral program between Flanders and Brazil. ; Approved Most recent IF: 2.649; 2012 IF: 2.355
Call Number UA @ lucian @ c:irua:101838 Serial 1000
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Author Zhang, L.-F.; Covaci, L.; Milošević, M.V.; Berdiyorov, G.R.; Peeters, F.M.
Title Unconventional vortex states in nanoscale superconductors due to shape-induced resonances in the inhomogeneous Cooper-pair condensate Type A1 Journal article
Year 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 109 Issue 10 Pages 107001
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Vortex matter in mesoscopic superconductors is known to be strongly affected by the geometry of the sample. Here we show that in nanoscale superconductors with coherence length comparable to the Fermi wavelength the shape resonances of the order parameter results in an additional contribution to the quantum topological confinement-leading to unconventional vortex configurations. Our Bogoliubov-de Gennes calculations in a square geometry reveal a plethora of asymmetric, giant multivortex, and vortex-antivortex structures, stable over a wide range of parameters and which are very different from those predicted by the Ginzburg-Landau theory. These unconventional states are relevant for high-T-c nanograins, confined Bose-Einstein condensates, and graphene flakes with proximity-induced superconductivity.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos (up) 000308295700014 Publication Date 2012-09-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 31 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen). ; Approved Most recent IF: 8.462; 2012 IF: 7.943
Call Number UA @ lucian @ c:irua:101850 Serial 3801
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Author Szumniak, P.; Bednarek, S.; Partoens, B.; Peeters, F.M.
Title Spin-orbit-mediated manipulation of heavy-hole spin qubits in gated semiconductor nanodevices Type A1 Journal article
Year 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 109 Issue 10 Pages 107201
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A novel spintronic nanodevice is proposed that is able to manipulate the single heavy-hole spin state in a coherent manner. It can act as a single quantum logic gate. The heavy-hole spin transformations are realized by transporting the hole around closed loops defined by metal gates deposited on top of the nanodevice. The device exploits Dresselhaus spin-orbit interaction, which translates the spatial motion of the hole into a rotation of the spin. The proposed quantum gate operates on subnanosecond time scales and requires only the application of a weak static voltage which allows for addressing heavy-hole spin qubits individually. Our results are supported by quantum mechanical time-dependent calculations within the four-band Luttinger-Kohn model.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos (up) 000308295700015 Publication Date 2012-09-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 41 Open Access
Notes ; This work was supported by the Grant No. NN202 128337 from the Ministry of Science and Higher Education, as well as by the “Krakow Interdisciplinary PhD-Project in Nanoscience and Advances Nanostructures” operated within the Foundation for Polish Science MPD Programme and cofinanced by European Regional Development Fund, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-V1). ; Approved Most recent IF: 8.462; 2012 IF: 7.943
Call Number UA @ lucian @ c:irua:101849 Serial 3094
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Author Van Dael, M.; Van Passel, S.; Pelkmans, L.; Guisson, R.; Swinnen, G.; Schreurs, E.
Title Determining potential locations for biomass valorization using a macro screening approach Type A1 Journal article
Year 2012 Publication Biomass & Bioenergy Abbreviated Journal Biomass Bioenerg
Volume 45 Issue Pages 175-186
Keywords A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM)
Abstract European policy states that by 2020 at least 20% of final energy consumption should come from renewable energy sources. Biomass as a renewable energy source cannot be disregarded in order to attain this target. In this study a macro screening approach is developed to determine potential locations for biomass valorization in a specified region. The approach consists of five steps: (1) criteria determination, (2) data gathering, (3) weight assignment, (4) final score, (5) spatial representation. The resulting outcome provides a first well balanced scan of the possibilities for energy production using regional biomass. This way policy makers and investors can be supported and motivated to study the possibilities of building energy production plants at specific locations in more detail, which can be described as a 'micro-screening'. In our case study the approach is applied to determine the potentially interesting locations to establish a biomass project. The region has been limited to the forty-four communities in the province of Limburg (Belgium). The macro screening approach has shown to be very effective since the amount of interesting locations has been reduced drastically. (c) 2012 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000308384500019 Publication Date 2012-06-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0961-9534 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.219 Times cited 23 Open Access
Notes ; The authors gratefully acknowledge the financial support from INTERREG and the province of Limburg. Special thanks to our colleague Thomas Voets for his effort in making the GIS maps. Moreover, the authors would like to thank the two anonymous reviewers for their valuable comments. ; Approved Most recent IF: 3.219; 2012 IF: 2.975
Call Number UA @ admin @ c:irua:127554 Serial 6178
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Author Komendová, L.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M.
Title The healing lengths in two-band superconductors in extended Ginzburg-Landau theory Type A1 Journal article
Year 2012 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 479 Issue Pages 126-129
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the vortex profiles in two-gap superconductors using the extended Ginzburg-Landau theory. The results shed more light on the disparity between the effective length scales in two bands. We compare the behavior expected from the standard Ginzburg-Landau theory with this new approach, and find good qualitative agreement in the case of LiFeAs. (C) 2011 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000308580600029 Publication Date 2012-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 1 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: 1.404; 2012 IF: 0.718
Call Number UA @ lucian @ c:irua:101871 Serial 3585
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Author Zhao, H.J.; Misko, V.R.; Peeters, F.M.
Title Vortex configurations with non-monotonic interaction Type A1 Journal article
Year 2012 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 479 Issue Pages 130-133
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The pattern formation of the vortex states with non-monotonic inter-vortex interaction is investigated. Our applied model has a short-range repulsive (r < r(c)) and long-range attractive (r > r(c)) potential. We numerically calculate the stable states using molecular-dynamics simulations. The obtained vortex patterns are comparable with the vortices states in low kappa type-II superconductors and recently discovered "type-1.5'' superconductors. We also analyze the nearest neighbor distribution of the obtained patterns. (C) 2012 Published by Elsevier B.V.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000308580600030 Publication Date 2012-01-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 9 Open Access
Notes ; We acknowledge fruitful discussions with Ernst Helmut Brandt. This work was supported by the "Odysseus'' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the IAP and FWO-Vl. ; Approved Most recent IF: 1.404; 2012 IF: 0.718
Call Number UA @ lucian @ c:irua:101872 Serial 3864
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Author Sivek, J.; Leenaerts, O.; Partoens, B.; Peeters, F.M.
Title First-principles investigation of bilayer fluorographene 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 36 Pages 19240-19245
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Ab initio calculations within the density functional theory formalism are performed to investigate the stability and electronic properties of fluorinated bilayer graphene (bilayer fluorographene). A comparison is made to previously investigated graphane, bilayer graphane, and fluorographene. Bilayer fluorographene is found to be a much more stable material than bilayer graphane. Its electronic band structure is similar to that of monolayer fluorographene, but its electronic band gap is significantly larger (about 1 eV). We also calculate the effective masses around the Gamma-point for fluorographene and bilayer fluorographene and find that they are isotropic, in contrast to earlier reports. Furthermore, it is found that bilayer fluorographene is almost as strong as graphene, as its 2D Young's modulus is approximately 300 N m(-1).
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000308631300022 Publication Date 2012-08-21
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 39 Open Access
Notes ; This work is supported by the ESF-Eurocores program EuroGRAPHENE (project CONERAN) and the Flemish Science Foundation (FWO-V1). ; Approved Most recent IF: 4.536; 2012 IF: 4.814
Call Number UA @ lucian @ c:irua:101842 Serial 1211
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Author Shanenko, A.A.; Croitoru, M.D.; Vagov, A.V.; Axt, V.M.; Perali, A.; Peeters, F.M.
Title Atypical BCS-BEC crossover induced by quantum-size effects Type A1 Journal article
Year 2012 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
Volume 86 Issue 3 Pages 033612
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Quantum-size oscillations of the basic physical characteristics of a confined fermionic condensate are a well-known phenomenon. Its conventional understanding is based on the single-particle physics, whereby the oscillations follow variations in the single-particle density of states driven by the size quantization. Here we present a study of a cigar-shaped ultracold superfluid Fermi gas, which demonstrates an important many-body aspect of the quantum-size coherent effects, overlooked previously. The many-body physics is revealed here in the atypical crossover from the Bardeen-Cooper-Schrieffer (BCS) superfluid to the Bose-Einstein condensate (BEC) induced by the size quantization of the particle motion. The single-particle energy spectrum for the transverse dimensions is tightly bound, whereas for the longitudinal direction it resembles a quasi-free dispersion. This results in the formation of a series of single-particle subbands (shells) so that the aggregate fermionic condensate becomes a coherent mixture of subband condensates. Each time when the lower edge of a subband crosses the chemical potential, the BCS-BEC crossover is approached in this subband, and the aggregate condensate contains both BCS and BEC-like components.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos (up) 000308639500004 Publication Date 2012-09-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.925 Times cited 34 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). The authors thank C. Salomon and C. Vale for their valuable explications of the experimental situation and interest to our work. We are grateful to G. C. Strinati, D. Neilson, and P. Pieri for useful discussions. M. D. C. acknowledges support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). A. P. gratefully acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 4844 for his visit to the University of Antwerp. A. A. S. acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 5200 for his visit to the University of Camerino. ; Approved Most recent IF: 2.925; 2012 IF: 3.042
Call Number UA @ lucian @ c:irua:101844 Serial 203
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Author Fenu, A.; De Wilde, W.; Gaertner, M.; Weemaes, M.; de Gueldre, G.; van de Steene, B.
Title Elaborating the membrane life concept in a full scale hollow-fibers MBR Type A1 Journal article
Year 2012 Publication Journal of membrane science Abbreviated Journal
Volume 421 Issue Pages 349-354
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The membrane life-time has a strong impact on competitivity and viability of MBRs. This study critically analyzes the membrane life-time concept, approaching it through different assessment methods. A full scale MBR's membrane life-time was assessed on the following: (i) maintaining the permeate flow throughput to the MBR; (ii) the permeability decline; (iii) oxidative aging; (iv) the increase in energy costs; and (v) mechanical aging. The method based on permeability decline provides a membrane life-time estimate up to a theoretical end. It was further elaborated inherently to operations with no long-term flux decline. The increase in operating pressure remains the main end-of-life trigger for deciding when to replace membrane modules. On the contrary, mechanical and permeate flow throughput analysis of the data are not able to provide a clear estimate of the membrane life-time. As for the membrane life-time estimation based on chlorine contact, it was found to be too optimistic. Complete irreversible fouling occurs before maximum contact time with chlorine is reached. At end-of-life operating conditions, the energy consumption raised of 170% due to the reduced flow rate. The cost raise appears high but still affordable. Earlier membrane replacement thus can never be counterbalanced by energy costs saving. (C) 2012 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000308741100039 Publication Date 2012-08-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0376-7388 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:101790 Serial 7856
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Author Nowak, M.P.; Szafran, B.; Peeters, F.M.
Title Resonant harmonic generation and collective spin rotations in electrically driven quantum dots Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 12 Pages 125428
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Spin rotations induced by an ac electric field in a two-electron double quantum dot are studied by an exact numerical solution of the time-dependent Schrodinger equation in the context of recent electric-dipole spin resonance experiments on gated nanowires. We demonstrate that the splitting of the main resonance line by the spin exchange coupling is accompanied by the appearance of fractional resonances and that both these effects are triggered by interdot tunnel coupling. We find that the ac-driven system generates residual but distinct harmonics of the driving frequency, which are amplified when tuned to the main transition frequency. The mechanism is universal for electron systems in electrically driven potentials and works also in the absence of electron-electron interaction or spin-orbit coupling.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000308867300005 Publication Date 2012-09-21
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 29 Open Access
Notes ; This work was supported by funds of the Ministry of Science and Higher Education (MNiSW) for 2012-2013 under Project No. IP2011038671, and by PL-Grid Infrastructure. M.P.N. gratefully acknowledges support from the Foundation for Polish Science (FNP) under START and MPD program cofinanced by the EU European Regional Development Fund. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:101839 Serial 2885
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Author Euán-Díaz, E.C.; Misko, V.R.; Peeters, F.M.; Herrera-Velarde, S.; Castaneda-Priego, R.
Title Single-file diffusion in periodic energy landscapes : the role of hydrodynamic interactions Type A1 Journal article
Year 2012 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 86 Issue 3Part 1 Pages 031123
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We report on the dynamical properties of interacting colloids confined to one dimension and subjected to external periodic energy landscapes. We particularly focus on the influence of hydrodynamic interactions on the mean-square displacement. Using Brownian dynamics simulations, we study colloidal systems with two types of repulsive interparticle interactions, namely, Yukawa and superparamagnetic potentials. We find that in the homogeneous case, hydrodynamic interactions lead to an enhancement of the particle mobility and the mean-square displacement at long times scales as t(alpha), with alpha = 1/2 + epsilon and epsilon being a small correction. This correction, however, becomes much more important in the presence of an external field, which breaks the homogeneity of the particle distribution along the line and, therefore, promotes a richer dynamical scenario due to the hydrodynamical coupling among particles. We provide here the complete dynamical scenario in terms of the external potential parameters: amplitude and commensurability.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos (up) 000308873500002 Publication Date 2012-09-21
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 14 Open Access
Notes ; This work was partially supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), and PIFI 3.4-PROMEP and CONACyT (Grant Nos. 61418/2007 and 102339/2008, Ph.D. Scholarship No. 230171/ 2010). ; Approved Most recent IF: 2.366; 2012 IF: 2.313
Call Number UA @ lucian @ c:irua:101840 Serial 3021
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Author Gotter, R.; Fratesi, G.; Bartynski, R.A.; da Pieve, F.; Offi, F.; Ruocco, A.; Ugenti, S.; Trioni, M.I.; Brivio, G.P.; Stefani, G.
Title Spin-dependent on-site electron correlations and localization in itinerant f erromagnets Type A1 Journal article
Year 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 109 Issue 12 Pages 126401
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Spin selectivity in angle-resolved Auger photoelectron coincidence spectroscopy (AR-APECS) is used to probe electron correlation in ferromagnetic thin films. In particular, exploiting the AR-APECS capability to discriminate Auger electron emission events characterized by valence hole pairs created either in the high or in the low total spin state, a strong correlation effect in the Fe M2,3VV Auger line shape (measured in coincidence with the Fe 3p photoelectrons) of Fe/Cu(001) thin films is detected and ascribed to interactions within the majority spin subband. Such an assignment follows from a close comparison of the experimental AR-APECS line shapes with the predictions of a model based on spin polarized density functional theory and the Cini-Sawatzky approach.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos (up) 000308877000002 Publication Date 2012-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 9 Open Access
Notes Approved Most recent IF: 8.462; 2012 IF: 7.943
Call Number UA @ lucian @ c:irua:101841 Serial 3084
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Author Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Herber, R.H.; Nowik, I.; Hodges, J.P.; Dachraoui, W.; Hadermann, J.; Greenblatt, M.;
Title High magnetic ordering temperature in the perovskites Sr4-xLaxFe3ReO12 (x=0.0, 1.0, 2.0) Type A1 Journal article
Year 2012 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 194 Issue Pages 48-58
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A series of perovskites Sr4−xLaxFe3ReO12 (x=0.0, 1.0, 2.0) has been prepared by wet chemistry methods. The structure analyses by powder X-ray and neutron diffraction and electron microscopy show that these compounds adopt simple perovskite structures without cation ordering over the B sites: tetragonal (I4/mcm) for x=0.0 and 1.0 and orthorhombic (Pbmn) for x=2.0. The oxidation states of the cations in the compound with x=0.0 appear to be Fe3+/4+ and Re7+ and decrease for both with La substitution as evidenced by X-ray absorption spectroscopy. All the compounds are antiferromagnetically ordered above room temperature, as demonstrated by Mössbauer spectroscopy and the magnetic structures, which were determined by powder neutron diffraction. The substitution of Sr by La strongly affects the magnetic properties with an increase of TN up to ∼750 K.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000308896400009 Publication Date 2012-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 9 Open Access
Notes Approved Most recent IF: 2.299; 2012 IF: 2.040
Call Number UA @ lucian @ c:irua:101220 Serial 1435
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Author Mortet, V.; Zhang, L.; Eckert, M.; D'Haen, J.; Soltani, A.; Moreau, M.; Troadec, D.; Neyts, E.; De Jaeger, J.C.; Verbeeck, J.; Bogaerts, A.; Van Tendeloo, G.; Haenen, K.; Wagner, P.
Title Grain size tuning of nanocrystalline chemical vapor deposited diamond by continuous electrical bias growth : experimental and theoretical study Type A1 Journal article
Year 2012 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A
Volume 209 Issue 9 Pages 1675-1682
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this work, a detailed structural and spectroscopic study of nanocrystalline diamond (NCD) thin films grown by a continuous bias assisted CVD growth technique is reported. This technique allows the tuning of grain size and phase purity in the deposited material. The crystalline properties of the films are characterized by SEM, TEM, EELS, and Raman spectroscopy. A clear improvement of the crystalline structure of the nanograined diamond film is observed for low negative bias voltages, while high bias voltages lead to thin films consisting of diamond grains of only ∼10 nm nanometer in size, showing remarkable similarities with so-called ultrananocrystalline diamond. These layers arecharacterized by an increasing amount of sp2-bonded carbon content of the matrix in which the diamond grains are embedded. Classical molecular dynamics simulations support the observed experimental data, giving insight in the underlying mechanism for the observed increase in deposition rate with bias voltage. Furthermore, a high atomic concentration of hydrogen has been determined in these films. Finally, Raman scattering analyses confirm that the Raman line observed at ∼1150 cm−1 cannot be attributed to trans-poly-acetylene, which continues to be reported in literature, reassigning it to a deformation mode of CHx bonds in NCD.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000308942100009 Publication Date 2012-09-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6300; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.775 Times cited 31 Open Access
Notes M.E. and E.N. acknowledge financial support from, respectively, the Institute for Promotion of Innovation through Science and Technology in Flanders (IWT), and the Research Foundation-Flanders (FWO). J.V. gratefully acknowledges financial support from the GOA project “XANES meets ELNES” of the research fund of the University of Antwerp. Calculation support was provided by the University of Antwerp through the core facility CALCUA. G.V.T. acknowledges the ERC grant COUNTATOMS. The work was also financially supported by the joint UAUHasseltMethusalem “NANO” network, the Research Programs G.0068.07 and G.0555.10N of the Research Foundation-Flanders (FWO), the IAP-P6/42 project “Quantum Effects in Clusters and Nanowires”, and by the EU FP7 through the Integrated Infrastructure Initiative “ESMI” (No. 262348), the Marie Curie ITN “MATCON” (PITN-GA-2009-238201), and the Collaborative Project “DINAMO” (No. 245122). Approved Most recent IF: 1.775; 2012 IF: 1.469
Call Number UA @ lucian @ c:irua:101516UA @ admin @ c:irua:101516 Serial 1364
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Author Tirry, W.; Bouvier, S.; Benmhenni, N.; Hammami, W.; Habraken, A.M.; Coghe, F.; Schryvers, D.; Rabet, L.
Title Twinning in pure Ti subjected to monotonic simple shear deformation Type A1 Journal article
Year 2012 Publication Materials characterization Abbreviated Journal Mater Charact
Volume 72 Issue Pages 24-36
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The aim of this paper is to provide a thorough study on the occurrence and importance of deformation twinning in simple shear deformed pure α-Ti. A statistically relevant inspection of the morphology of the deformation twins in relation to the applied strain/deformation is performed. The investigated microstructural aspects are the twin volume fraction, the twin thickness distribution and the resolved shear stress distribution on the twin plane. All these aspects are examined as a function of the twin types and two initial textures. Monotonic simple shear experiments are carried out for three different loading directions with respect to a direction linked to the initial crystallographic texture. EBSD and TEM observations reveal the presence of View the MathML source and View the MathML source twins. The statistical analysis reveals that View the MathML source and View the MathML source twins have a similar average thickness around 1.9 nm, but the View the MathML source twins show a far larger spread on their thickness and can grow to almost the size of the original parent grain. Correlation of the twin fractions with the RSS analysis shows that RSS is an acceptable method explaining the difference in twin fractions for different textures and orientations. A detailed analysis shows that View the MathML source twins occur in average with a smaller volume fraction but with a higher RSS, indicating they are more difficult to nucleate or grow compared to View the MathML source twinning. In general a higher RSS value on the twin plane is not connected to a higher twin thickness; only in the case of View the MathML source twins the highest RSS values show clearly thicker twins.
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Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos (up) 000309086700004 Publication Date 2012-07-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1044-5803; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.714 Times cited 25 Open Access
Notes Iap Approved Most recent IF: 2.714; 2012 IF: 1.880
Call Number UA @ lucian @ c:irua:101225 Serial 3768
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