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Author Park, K.; De Beule, C.; Partoens, B. url  doi
openurl 
  Title The ageing effect in topological insulators : evolution of the surface electronic structure of Bi2Se3 upon K adsorption Type A1 Journal article
  Year 2013 Publication New journal of physics Abbreviated Journal New J Phys  
  Volume 15 Issue Pages 113031-16  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Topological insulators (TIs) have attracted a lot of interest in recent years due to their topologically protected surface states, as well as exotic proximity-induced phenomena and device applications for TI heterostructures. Since the first experimental studies of TIs, angle-resolved photoemission spectra (ARPES) showed that the electronic structure of the topological surface states significantly changes as a function of time after cleavage. The origin and underlying mechanism of this ageing effect are still under debate, despite its importance. Here we investigate the evolution of the surface Dirac cone for Bi2Se3 films upon asymmetric potassium (K) adsorption, using density-functional theory and a tight-binding model. We find that the K adatoms induce short-ranged downward band bending within 2-3 nm from the surface, due to charge transfer from the adatoms to the TI. These findings are in contrast to earlier proposals in the literature, that propose a long-ranged downward band bending up to 15 nm from the surface. Furthermore, as the charge transfer increases, we find that a new Dirac cone, localized slightly deeper into the TI than the original one, appears at the K-adsorbed surface, originating from strong Rashba-split conduction-band states. Our results suggest possible reinterpretations of experiments because the new Dirac cone might have been observed in ARPES measurements instead of the original one that appears immediately after cleavage. Our findings are consistent with ARPES data and provide insight into building TI-heterostructure devices by varying the band-bending potential or film thickness.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000326876100006 Publication Date 2013-11-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1367-2630; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.786 Times cited 45 Open Access  
  Notes ; KP was supported by National Science Foundation grant numbers DMR-0804665 and DMR-1206354 and SDSC Trestles under DMR060009N. CDB was supported by the Research Foundation Flanders (FWO). ; Approved Most recent IF: 3.786; 2013 IF: 3.671  
  Call Number UA @ lucian @ c:irua:112707 Serial 84  
Permanent link to this record
 

 
Author Skaltsas, T.; Ke, X.; Bittencourt, C.; Tagmatarchis, N. doi  openurl
  Title Ultrasonication induces oxygenated species and defects onto exfoliated graphene Type A1 Journal article
  Year 2013 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 117 Issue 44 Pages 23272-23278  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The effect of ultrasonication parameters, such as time and power applied, to exfoliate graphite in o-dichlorobenzene (o-DCB) and N-methyl-1,2-pyrrolidone (NMP) was examined. It was found that the concentration of graphene was higher in o-DCB, while its dispersibility was increased when sonication was applied for a longer period and/or at higher power. However, spectroscopic examination by X-ray photoelectron spectroscopy (XPS) revealed that ultrasonication causes defects and induces oxygen functional groups in the form of carboxylic acids and ethers/epoxides onto the graphene lattice. Additional proof for the latter arose from Raman, IR, and thermogravimetry studies. The carboxylic acids and ethers/epoxides onto exfoliated graphene were derived from air during ultrasonication and found independent of the solvent used for the exfoliation and the power and/or time ultrasonication applied. Quantitative evaluation of the amount of oxygenated species present on exfoliated graphene as performed by high-resolution XPS revealed that the relative oxygen percentage was higher when exfoliation was performed in NMP. Finally, the sonication time and/or power affected the oxygen content on exfoliated graphene, since extended ultrasonication resulted in a decrease in the oxygen content on exfoliated graphene, with a simultaneous increase of defected sp(3) carbon atoms.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000326845400090 Publication Date 2013-10-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447;1932-7455; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 65 Open Access  
  Notes Approved Most recent IF: 4.536; 2013 IF: 4.835  
  Call Number UA @ lucian @ c:irua:112710 Serial 3797  
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Author Badalyan, S.M.; Matos-Abiague, A.; Fabian, J.; Vignale, G.; Peeters, F.M. url  doi
openurl 
  Title Spin-orbit-interaction induced singularity of the charge density relaxation propagator Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 19 Pages 195402-195405  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The charge density relaxation propagator of a two-dimensional electron system, which is the slope of the imaginary part of the polarization function, exhibits singularities for bosonic momenta having the order of the spin-orbit momentum and depending on the momentum orientation. We have provided an intuitive understanding for this nonanalytic behavior in terms of the interchirality subband electronic transitions, induced by the combined action of Bychkov-Rashba (BR) and Dresselhaus (D) spin-orbit coupling. It is shown that the regular behavior of the relaxation propagator is recovered in the presence of only one BR or D spin-orbit field or for spin-orbit interaction with equal BR and D coupling strengths. This creates a new possibility to influence carrier relaxation properties by means of an applied electric field.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000326820200005 Publication Date 2013-11-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 2 Open Access  
  Notes ; We acknowledge support from the Methusalem program of the Flemish government and the Flemish Science Foundation (FWO-Vl), DFG SFB Grant 689, and NSF Grant DMR-1104788 (G.V.). ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:112711 Serial 3093  
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Author Shakouri, K.; Badalyan, S.M.; Peeters, F.M. url  doi
openurl 
  Title Helical liquid of snake states Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 19 Pages 195404-195405  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We derive an exact solution to the problem of spin snake states induced in a nonhomogeneous magnetic field by a combined action of the Rashba spin-orbit and Zeeman fields. The electron spin behavior as a function of the cyclotron orbit center position and an external homogeneous magnetic field was obtained. It is shown that in an antisymmetric magnetic field the electron spin in the snake states has only an in-plane projection, perpendicular to the magnetic interface, which vanishes at large positive momenta. Applying an external homogeneous magnetic field adds a finite out-of-plane spin component and simultaneously gaps out the spectral branches, which results in regular beating patterns of the spin current components.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000326820200007 Publication Date 2013-11-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 3 Open Access  
  Notes ; This work was supported by the Methusalem program of the Flemish government and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:112712 Serial 1416  
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Author Retuerto, M.; Li, M.R.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Chi, S.; Hodges, J.P.; Dachraoui, W.; Hadermann, J.; Tran, T.T.; Halasyamani, P.S.; Grams, C.P.; Hemberger, J.; Greenblatt, M.; doi  openurl
  Title Polar and magnetic layered A-site and rock salt B-site-ordered NaLnFeWO6 (Ln = La, Nd) perovskites Type A1 Journal article
  Year 2013 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 52 Issue 21 Pages 12482-12491  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We have expanded the double perovskite family of materials with the unusual combination of layered order in the A sublattice and rock salt order over the B sublattice to compounds NaLaFeWO6 and NaNdFeWO6. The materials have been synthesized and studied by powder X-ray diffraction, neutron diffraction, electron diffraction, magnetic measurements, X-ray absorption spectroscopy, dielectric measurements, and second harmonic generation. At room temperature, the crystal structures of both compounds can be defined in the noncentrosymmetric monoclinic P2(1) space group resulting from the combination of ordering both in the A and B sublattices, the distortion of the cell due to tilting of the octahedra, and the displacement of certain cations. The magnetic studies show that both compounds are ordered antiferromagnetically below T-N approximate to 25 K for NaLaFeWO6 and at similar to 21 K for NaNdFeWO6. The magnetic structure of NaNdFeWO6 has been solved with a propagation vector k = (1/2 0 1/2) as an antiferromagnetic arrangement of Fe and Nd moments. Although the samples are potential multiferroics, the dielectric measurements do not show a ferroelectric response.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Easton, Pa Editor  
  Language Wos 000326669200035 Publication Date 2013-10-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1669;1520-510X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.857 Times cited 17 Open Access  
  Notes Approved Most recent IF: 4.857; 2013 IF: 4.794  
  Call Number UA @ lucian @ c:irua:112714 Serial 2656  
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Author Tan, H.; Egoavil, R.; Béché, A.; Martinez, G.T.; Van Aert, S.; Verbeeck, J.; Van Tendeloo, G.; Rotella, H.; Boullay, P.; Pautrat, A.; Prellier, W. url  doi
openurl 
  Title Mapping electronic reconstruction at the metal-insulator interface in LaVO3/SrVO3 heterostructures Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 15 Pages 155123-155126  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A (LaVO3)6/(SrVO3)(3) superlattice is studied with a combination of sub-A resolved scanning transmission electron microscopy and monochromated electron energy-loss spectroscopy. The V oxidation state is mapped with atomic spatial resolution enabling us to investigate electronic reconstruction at the LaVO3/SrVO3 interfaces. Surprisingly, asymmetric charge distribution is found at adjacent chemically symmetric interfaces. The local structure is proposed and simulated with a double channeling calculation which agrees qualitatively with our experiment. We demonstrate that local strain asymmetry is the likely cause of the electronic asymmetry of the interfaces. The electronic reconstruction at the interfaces extends much further than the chemical composition, varying from 0.5 to 1.2 nm. This distance corresponds to the length of charge transfer previously found in the (LaVO3)./(SrVO3). metal/insulating and the (LaAlO3)./(SrTiO3). insulating/insulating interfaces.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000326087100003 Publication Date 2013-10-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 15 Open Access  
  Notes Hercules; 246791 COUNTATOMS; 278510 VORTEX; 246102 IFOX; 312483 ESTEEM2; FWO; GOA XANES meets ELNES; esteem2jra3 ECASJO; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:112733UA @ admin @ c:irua:112733 Serial 1944  
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Author Damm, H.; Kelchtermans, A.; Bertha, A.; Van den Broeck, F.; Elen, K.; Martins, J.C.; Carleer, R.; D'Haen, J.; De Dobbelaere, C.; Hadermann, J.; Hardy, A.; Van Bael, M.K.; doi  openurl
  Title Thermal decomposition synthesis of Al-doped ZnO nanoparticles : an in-depth study Type A1 Journal article
  Year 2013 Publication RSC advances Abbreviated Journal Rsc Adv  
  Volume 3 Issue 45 Pages 23745-23754  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Al-doped ZnO nanoparticles are synthesized by means of a heating up solution based thermal decomposition method. The synthesis involves a reaction of zinc acetylacetonate hydrate, aluminium acetylacetonate and 1,2-hexadecanediol in the presence of oleic acid and oleyl amine. A proposed reaction mechanism from reagents to monomers is corroborated by analysis of the evolving gases using headspace GC-MS analysis. The Al-doped ZnO nanoparticles synthesized are dynamically stabilized by adsorbed oleate ions, after deprotonation of oleic acid by oleyl amine, as was found by NOESY proton NMR and complementary FTIR spectroscopy. Precession electron diffraction shows a simultaneous increase in lattice parameters with Al concentration. This, together with HAADF-STEM and EDX maps, indicates the incorporation of Al into the ZnO nanoparticles. By the combination of complementary characterization methods during all stages of the synthesis, it is concluded that Al is incorporated into the ZnO wurtzite lattice as a dopant.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000326395800139 Publication Date 2013-10-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.108 Times cited 10 Open Access  
  Notes Approved Most recent IF: 3.108; 2013 IF: 3.708  
  Call Number UA @ lucian @ c:irua:112753 Serial 3627  
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Author van Winsen, F.; de Mey, Y.; Lauwers, L.; Van Passel, S.; Vancauteren, M.; Wauters, E. pdf  doi
openurl 
  Title Cognitive mapping : a method to elucidate and present farmers' risk perception Type A1 Journal article
  Year 2013 Publication Agricultural Systems Abbreviated Journal Agr Syst  
  Volume 122 Issue Pages 42-52  
  Keywords A1 Journal article  
  Abstract Assumptions on the perceptions of risks, made in agricultural economics literature, are recognized to be over-simplistic. For example most studies assume that risks are independent and static, while in reality most risks are interlinked and dynamic. We propose an alternative method to identify and present risk perception, closer to the actual comprehension of risk by farmers. Grounded theory is used to investigate the perceptions of risk by farmers while avoiding prior assumptions. Main findings are: (i) farmers have difficulty to rank or score probability and impact of risks in a (semi)quantitative manner; (ii) farmers attach different meanings to risk, when the focus shifts between, uncertain event, probability or value at stake and; (iii) farmers perceive risks as being interrelated. Based on these findings, we propose that farmers' risk perception can be best understood as a network of interrelated notions of uncertain events, their effects and uncertain outcomes. Furthermore, cognitive mapping is suggested to elucidate and present these networks. We test cognitive mapping, exploring dairy farmers' risk perception, and demonstrate the appropriateness of this methodology for capturing the complexity and context of perceived risk. Advantages are: (i) the qualitative approach, (ii) the focus on interrelations and context, (iii) the applicability at farm level, (iv) the farmer-driven rather than researcher-driven perspective, and (v) the elucidation of the polyvalent use of the risk concept. Cognitive maps can be used as a communication tool, a risk management tool, and a tool to stimulate bi-directional learning amongst farmers, policy makers, researchers and extension agents. (C) 2013 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000326910500005 Publication Date 2013-09-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0308-521x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.571 Times cited 27 Open Access  
  Notes ; We would like to acknowledge the Agency for Innovation by Science and Technology of the Flemish Government (IWT) for funding this research. Furthermore we would like to thank the anonymous reviewers for their valuable input. ; Approved Most recent IF: 2.571; 2013 IF: 2.453  
  Call Number UA @ admin @ c:irua:112765 Serial 6168  
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Author Baken, S.; Sjostedt, C.; Gustafsson, J.P.; Seuntjens, P.; Desmet, N.; De Schutter, J.; Smolders, E. pdf  doi
openurl 
  Title Characterisation of hydrous ferric oxides derived from iron-rich groundwaters and their contribution to the suspended sediment of streams Type A1 Journal article
  Year 2013 Publication Applied geochemistry Abbreviated Journal  
  Volume 39 Issue Pages 59-68  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract When Fe(II) bearing groundwaters surface in streams, particulate authigenic Fe-rich material is produced by oxidation. Such freshly precipitated Fe minerals may be transported as suspended sediment and have a profound impact on the fate of trace metals and nutrients in rivers. The objective of this study was to monitor changes in mineralogy and composition of authigenic material from its source to streams of increasing order. Groundwaters, surface waters, and suspended sediment in streams of different order were sampled in the Kleine Nete catchment (Belgium), a lowland with Fe-rich groundwaters (3.5-53.8 mg Fe/L; pH 6.3-6.9). Fresh authigenic material (>0.45 mu m) was produced by oxidising filtered (<0.45 mu m) groundwater and surface water. This material contained, on average, 44% Fe, and smaller concentrations of C, P, and Ca. Iron EXAFS (Extended X-ray Absorption Fine Structure) spectroscopy showed that the Fe was present as poorly crystalline hydrous ferric oxides with a structure similar to that of ferrihydrite. The Fe concentration in the suspended sediment samples decreased to 36-40% (stream order 2), and further to 18-26% (stream order 4 and 5). Conversely, the concentrations of organic C, Ca, Si, and trace metals increased with increasing stream order, suggesting mixing of authigenic material with suspended sediment from a different source. The Fe speciation in the suspended sediment was similar to that in fresh authigenic material, but more Fe-Fe interactions were observed, i.e. it was increasingly hydrolysed, suggesting ageing reactions. The suspended sediment in the streams of order 4 and 5 is estimated to contain between 31% and 59% of authigenic material, but more data are needed to refine this estimate. The authigenic material is an important sink for P in these streams which may alleviate the eutrophication risk in this catchment. (C) 2013 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000327488700007 Publication Date 2013-10-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0883-2927 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:112769 Serial 7595  
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Author Rodríguez-Fernández, D.; Altantzis, T.; Heidari, H.; Bals, S.; Liz-Marzan, L.M. pdf  url
doi  openurl
  Title A protecting group approach toward synthesis of Au-silica Janus nanostars Type A1 Journal article
  Year 2014 Publication Chemical communications Abbreviated Journal Chem Commun  
  Volume 50 Issue 1 Pages 79-81  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The concept of protecting groups, widely used in organic chemistry, has been applied for the synthesis of Au-silica Janus stars, in which gold branches protrude from one half of Au-silica Janus spheres. This configuration opens up new possibilities to apply the plasmonic properties of gold nanostars, as well as a variety of chemical functionalizations on the silica component.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000327606000017 Publication Date 2013-10-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1359-7345;1364-548X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.319 Times cited 26 Open Access OpenAccess  
  Notes 262348 Esmi; 335078 Colouratom; 267867 Plasmaquo; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 6.319; 2014 IF: 6.834  
  Call Number UA @ lucian @ c:irua:112774 Serial 2732  
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Author Shariat, M.; Shokri, B.; Neyts, E.C. doi  openurl
  Title On the low-temperature growth mechanism of single walled carbon nanotubes in plasma enhanced chemical vapor deposition Type A1 Journal article
  Year 2013 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett  
  Volume 590 Issue Pages 131-135  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Despite significant progress in single walled carbon nanotube (SWCNT) production by plasma enhanced chemical vapor deposition (PECVD), the growth mechanism in this method is not clearly understood. We employ reactive molecular dynamics simulations to investigate how plasma-based deposition allows growth at low temperature. We first investigate the SWCNT growth mechanism at low and high temperatures under conditions similar to thermal CVD and PECVD. We then show how ion bombardment during the nucleation stage increases the carbon solubility in the catalyst at low temperature. Finally, we demonstrate how moderate energy ions sputter amorphous carbon allowing for SWCNT growth at 500 K. (C) 2013 Elsevier B. V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000327721000024 Publication Date 2013-10-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0009-2614; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.815 Times cited 14 Open Access  
  Notes Approved Most recent IF: 1.815; 2013 IF: 1.991  
  Call Number UA @ lucian @ c:irua:112775 Serial 2439  
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Author Morozov, V.A.; Bertha, A.; Meert, K.W.; Van Rompaey, S.; Batuk, D.; Martinez, G.T.; Van Aert, S.; Smet, P.F.; Raskina, M.V.; Poelman, D.; Abakumov, A.M.; Hadermann, J.; doi  openurl
  Title Incommensurate modulation and luminescence in the CaGd2(1-x)Eu2x(MoO4)4(1-y)(WO)4y (0\leq x\leq1, 0\leq y\leq1) red phosphors Type A1 Journal article
  Year 2013 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 25 Issue 21 Pages 4387-4395  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Scheelite related compounds (A',A '') [(B',B '')O-4], with B', B '' = W and/or Mo are promising new light-emitting materials for photonic applications, including phosphor converted LEDs (light-emitting diodes). In this paper, the creation and ordering of A-cation vacancies and the effect of cation substitutions in the scheelite-type framework are investigated as a factor for controlling the scheelite-type structure and luminescent properties. CaGd2(1-x)Eu2x(MoO4)(4(1-y))(WO4)(4y) (0 <= x <= 1, 0 <= y <= 1) solid solutions with scheelite-type structure were synthesized by a solid state method, and their structures were investigated using a combination of transmission electron microscopy techniques and powder X-ray diffraction. Within this series all complex molybdenum oxides have (3 + 2)D incommensurately modulated structures with superspace group I4(1)/a(alpha,beta,0)00(-beta,alpha,0)00, while the structures of all tungstates are (3 + 1)D incommensurately modulated with superspace group I2/b(alpha beta 0)00. In both cases the modulation arises because of cation-vacancy ordering at the A site. The prominent structural motif is formed by columns of A-site vacancies running along the c-axis. These vacant columns occur in rows of two or three aligned along the [110] direction of the scheelite subcell. The replacement of the smaller Gd3+ by the larger Eu3+ at the A-sublattice does not affect the nature of the incommensurate modulation, but an increasing replacement of Mo6+ by W6+ switches the modulation from (3 + 2)D to (3 + 1)D regime. Thus, these solid solutions can be considered as a model system where the incommensurate modulation can be monitored as a function of cation nature while the number of cation vacancies at the A sites remain constant upon the isovalent cation replacement. All compounds' luminescent properties were measured, and the optical properties were related to the structural properties of the materials. CaGd2(1-x)(MoO4)(4(1-y))(WO4)(4y) phosphors emit intense red light dominated by the D-5(0)-F-7(2) transition at 612 nm, along with other transitions from the D-5(1) and D-5(0) excited states. The intensity of the 5D0-7F2 transition reaches a maximum at x = 0.5 for y = 0 and 1.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000327045000030 Publication Date 2013-09-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756;1520-5002; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 63 Open Access  
  Notes Approved Most recent IF: 9.466; 2013 IF: 8.535  
  Call Number UA @ lucian @ c:irua:112776 Serial 1594  
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Author Idrissi, H.; Renard, K.; Schryvers, D.; Jacques, P.J. doi  openurl
  Title TEM investigation of the formation mechanism of deformation twins in Fe-Mn-Si-Al TWIP steels Type A1 Journal article
  Year 2013 Publication Philosophical magazine Abbreviated Journal Philos Mag  
  Volume 93 Issue 35 Pages 4378-4391  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The microstructure of a Fe-Mn-Si-Al twinning-induced plasticity (TWIP) steel exhibiting remarkable work hardening rate under uniaxial tensile deformation was investigated using transmission electron microscopy to uncover the mechanism(s) controlling the nucleation and growth of the mechanically induced twins. The results show that the stair-rod cross-slip deviation mechanism is necessary for the formation of the twins, while large extrinsic stacking faults homogenously distributed within the grains could act as preferential sources for the activation of the deviation process. The influence of such features on the thickness and strength of the twins and the resulting mechanical behaviour is discussed and compared to similar works recently performed on Fe-Mn-C TWIP steels.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000327478300005 Publication Date 2013-09-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1478-6435;1478-6443; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.505 Times cited 15 Open Access  
  Notes Approved Most recent IF: 1.505; 2013 IF: 1.427  
  Call Number UA @ lucian @ c:irua:112815 Serial 3478  
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Author Berdiyorov, G.R.; Peeters, F.M. doi  openurl
  Title Influence of vacancy defects on the thermal stability of silicene: a reactive molecular dynamics study Type A1 Journal article
  Year 2014 Publication RSC advances Abbreviated Journal Rsc Adv  
  Volume 4 Issue 3 Pages 1133-1137  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The effect of vacancy defects on the structural properties and the thermal stability of free standing silicene – a buckled structure of hexagonally arranged silicon atoms – is studied using reactive molecular dynamics simulations. Pristine silicene is found to be stable up to 1500 K, above which the system transits to a three-dimensional amorphous configuration. Vacancy defects result in local structural changes in the system and considerably reduce the thermal stability of silicene: depending on the size of the vacancy defect, the critical temperature decreases by more than 30%. However, the system is still found to be stable well above room temperature within our simulation time of 500 ps. We found that the, stability of silicene can be increased by saturating the dangling bonds at the defect edges by foreign atoms (e.g., hydrogen).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000327868400015 Publication Date 2013-11-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.108 Times cited 62 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. The authors are grateful to Prof. Adri van Duin for his support with the ReaxFF force field. ; Approved Most recent IF: 3.108; 2014 IF: 3.840  
  Call Number UA @ lucian @ c:irua:112829 Serial 1658  
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Author Wang, H.; Picot, T.; Houben, K.; Moorkens, T.; Grigg, J.; Van Haesendonck, C.; Biermans, E.; Bals, S.; Brown, S.A.; Vantomme, A.; Temst, K.; Van Bael, M.J.; pdf  doi
openurl 
  Title The superconducting proximity effect in epitaxial Al/Pb nanocomposites Type A1 Journal article
  Year 2014 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 27 Issue 1 Pages 015008-8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We have investigated the superconducting properties of Pb nanoparticles with a diameter ranging from 8 to 20 nm, synthesized by Pb+ ion implantation in a crystalline Al matrix. A detailed structural characterization of the nanocomposites reveals the highly epitaxial relation between the Al crystalline matrix and the Pb nanoparticles. The Al/Pb nanocomposites display a single superconducting transition, with the critical temperature T-c increasing with the Pb content. The dependence of T-c on the Pb/Al volume ratio was compared with theoretical models of the superconducting proximity effect based on the bulk properties of Al and Pb. A very good correspondence with the strong-coupling proximity effect model was found, with an electron-phonon coupling constant in the Pb nanoparticles slightly reduced compared to bulk Pb. Our result differs from other studies on Pb nanoparticle based proximity systems where weak-coupling models were found to better describe the T-c dependence. We infer that the high interface quality resulting from the ion implantation synthesis method is a determining factor for the superconducting properties. Critical field and critical current measurements support the high quality of the nanocomposite superconducting films.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000328275000010 Publication Date 2013-11-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 2 Open Access Not_Open_Access  
  Notes ; This work was supported by the Research Foundation-Flanders (FWO), the KU Leuven BOF Concerted Research Action programs (GOA/09/006, the KU Leuven BOF CREA/12/015 project, and GOA/14/007) and the EU FP7 program SPIRIT (227012). TP and KH are postdoctoral research fellow and doctoral fellow of the FWO. ; Approved Most recent IF: 2.878; 2014 IF: 2.325  
  Call Number UA @ lucian @ c:irua:112833 Serial 3599  
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Author Berdiyorov, G.R.; Savel'ev, S.E.; Kusmartsev, F.V.; Peeters, F.M. pdf  doi
openurl 
  Title In-phase motion of Josephson vortices in stacked SNS Josephson junctions : effect of ordered pinning Type A1 Journal article
  Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 26 Issue 12 Pages 125010-125016  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting Josephson junctions is investigated using the anisotropic time-dependent Ginzburg-Landau theory in the presence of a square/rectangular array of pinning centers (holes). For small values of the applied drive, fluxons in different junctions move out of phase, forming a periodic triangular lattice. A rectangular lattice of moving fluxons is observed at larger currents, which is in agreement with previous theoretical predictions (Koshelev and Aranson 2000 Phys. Rev. Lett. 85 3938). This 'superradiant' flux-flow state is found to be stable in a wide region of applied current. The stability range of this ordered state is considerably larger than the one obtained for the pinning-free sample. Clear commensurability features are observed in the current-voltage characteristics of the system with pronounced peaks in the critical current at (fractional) matching fields. The effect of density and strength of the pinning centers on the stability of the rectangular fluxon lattice is discussed. Predicted synchronized motion of fluxons in the presence of ordered pinning can be detected experimentally using the rf response of the system, where enhancement of the Shapiro-like steps is expected due to the synchronization.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000327447200013 Publication Date 2013-10-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 5 Open Access  
  Notes ; This work was supported by EU Marie Curie (Project No: 253057) and by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 2.878; 2013 IF: 2.796  
  Call Number UA @ lucian @ c:irua:112834 Serial 1573  
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Author Lubk, A.; Javon, E.; Cherkashin, N.; Reboh, S.; Gatel, C.; Hytch, M. pdf  doi
openurl 
  Title Dynamic scattering theory for dark-field electron holography of 3D strain fields Type A1 Journal article
  Year 2014 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 136 Issue Pages 42-49  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Dark-held electron holography maps strain in crystal lattices into reconstructed phases over large fields of view. Here we investigate the details of the lattice strain-reconstructed phase relationship by applying dynamic scattering theory both analytically and numerically. We develop efficient analytic linear projection rules for 3D strain fields, facilitating a straight-forward calculation of reconstructed phases from 3D strained materials. They are used in the following to quantify the influence of various experimental parameters like strain magnitude, specimen thickness, excitation error and surface relaxation. (C) 2013 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000327884700006 Publication Date 2013-07-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 18 Open Access  
  Notes European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference312483 – ESTEEM2); esteem2_jra4 Approved Most recent IF: 2.843; 2014 IF: 2.436  
  Call Number UA @ lucian @ c:irua:112836 Serial 766  
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Author Niermann, T.; Verbeeck, J.; Lehmann, M. pdf  doi
openurl 
  Title Creating arrays of electron vortices Type A1 Journal article
  Year 2014 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 136 Issue Pages 165-170  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We demonstrate the production of an ordered array of electron vortices making use of an electron optical setup consisting of two electrostatic biprisms. The biprism filaments are oriented nearly orthogonal with respect to each other in a transmission electron microscope. Matching the position of the filaments, we can choose to form different topological features in the electron wave. We outline the working principle of the setup and demonstrate fist experimental results. This setup partially bridges the gap between angular momentum carried by electron spin, which is intrinsic and therefore present in any position of the wave, and angular momentum carried by the vortex character of the wave, which can be extrinsic depending on the axis around which it is measured. (C) 2013 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000327884700021 Publication Date 2013-10-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 9 Open Access  
  Notes FP7; Countatoms; Vortex ECASJO_; Approved Most recent IF: 2.843; 2014 IF: 2.436  
  Call Number UA @ lucian @ c:irua:112837UA @ admin @ c:irua:112837 Serial 538  
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Author Aghaei, M.; Flamigni, L.; Lindner, H.; Günther, D.; Bogaerts, A. pdf  doi
openurl 
  Title Occurrence of gas flow rotational motion inside the ICP torch : a computational and experimental study Type A1 Journal article
  Year 2014 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 29 Issue 2 Pages 249-261  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract An inductively coupled plasma, connected to the sampling cone of a mass spectrometer, is computationally investigated. The occurrence of rotational motion of the auxiliary and carrier gas flows is studied. The effects of operating parameters, i.e., applied power and gas flow rates, as well as geometrical parameters, i.e., sampler orifice diameter and injector inlet diameter, are investigated. Our calculations predict that at higher applied power the auxiliary and carrier gas flows inside the torch move more forward to the sampling cone, which is validated experimentally for the auxiliary gas flow, by means of an Elan 6000 ICP-MS. Furthermore, an increase of the gas flow rates can also modify the occurrence of rotational motion. This is especially true for the carrier gas flow rate, which has a more pronounced effect to reduce the backward motion than the flow rates of the auxiliary and cooling gas. Moreover, a larger sampler orifice (e.g., 2 mm instead of 1 mm) reduces the backward flow of the auxiliary gas path lines. Finally, according to our model, an injector inlet of 2 mm diameter causes more rotations in the carrier gas flow than an injector inlet diameter of 1.5 mm, which can be avoided again by changing the operating parameters.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000329934000005 Publication Date 2013-11-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477;1364-5544; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 21 Open Access  
  Notes Approved Most recent IF: 3.379; 2014 IF: 3.466  
  Call Number UA @ lucian @ c:irua:112896 Serial 2427  
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Author Borovinskaya, O.; Aghaei, M.; Flamigni, L.; Hattendorf, B.; Tanner, M.; Bogaerts, A.; Günther, D. pdf  doi
openurl 
  Title Diffusion- and velocity-driven spatial separation of analytes from single droplets entering an ICP off-axis Type A1 Journal article
  Year 2014 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 29 Issue 2 Pages 262-271  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The reproducible temporal separation of ion signals generated from a single multi-element droplet, observed in previous studies, was investigated in detail in this work using an ICPTOFMS with high temporal resolution. It was shown that the signal peak intensities of individual elements temporally shift relative to each other only for droplets moving through the plasma off-axis. The magnitude of these shifts correlated with the vaporization temperatures of the analytes and depended on the radial position of the droplets as well as on the thermal properties and velocity profiles of the carrier gases of the ICP. The occurrence of the signal shifting was explained by a spatial separation of analytes already present in the vapor phase in the ICP from a yet unvaporized residue of the droplet. This separation is most likely driven by anisotropic diffusion of vaporized analytes towards the plasma axis and a radial velocity gradient. The proposed explanation is supported by modeling of the gas velocities inside the ICP and imaging of the atomic and ionic emissions produced from single droplets, whose patterns were sloping towards the center of the torch. The effects observed in these studies are important not only for the fundamental understanding of analyteplasma interactions but have also a direct impact on the signal intensities and stability.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000329934000006 Publication Date 2013-11-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477;1364-5544; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 18 Open Access  
  Notes Approved Most recent IF: 3.379; 2014 IF: 3.466  
  Call Number UA @ lucian @ c:irua:112897 Serial 697  
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Author Van Holsbeke, C.S.; Leemans, G.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Geldof, M.; Verdonck, P.R.; Parizel, P.M.; van Schil, P.E.; de Backer, W.A. pdf  doi
openurl 
  Title Functional Respiratory Imaging as a tool to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis Type A1 Journal article
  Year 2013 Publication Respiratory care Abbreviated Journal Resp Care  
  Volume Issue Pages 1-20  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract In two subjects with a unilateral diaphragmatic paralysis and complaints of dyspnea, a completely different treatment approach was chosen despite similar anatomical and physiological abnormalities. These decisions were supported by the results generated by Functional Respiratory Imaging (FRI). FRI was able to generate functional information with respect to lobar ventilation and local drug deposition. In one subject, it was found that some lobes were poorly ventilated and drug deposition simulation showed that some regions were undertreated. This subject underwent a diaphragm plication to restore the ventilation. In the other subject, it was found that all lobes were still ventilated. A conservative approach with regular follow-up was chosen to wait for spontaneous recovery of the diaphragmatic function. Both subjects improved subjectively and objectively. These cases demonstrate how novel medical imaging techniques such as FRI can be used to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Dallas, Tex. Editor  
  Language Wos 000349200100024 Publication Date 2013-12-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1324;1943-3654; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.733 Times cited 5 Open Access  
  Notes ; ; Approved Most recent IF: 1.733; 2013 IF: 1.840  
  Call Number UA @ lucian @ c:irua:112982 Serial 1303  
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Author de Oliveira, E.L.; Albuquerque, E.L.; de Sousa, J.S.; Farias, G.A.; Peeters, F.M. doi  openurl
  Title Configuration-interaction excitonic absorption in small Si/Ge and Ge/Si core/shell nanocrystals Type A1 Journal article
  Year 2012 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 116 Issue 7 Pages 4399-4407  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The excitonic properties of Si(core)/Ge(shell) and Ge(core)/Si(shell) nanocrystals (NC's) with diameters of similar to 1.9 nm are investigated using a combination density functional ab initio method to obtain the single particle wave functions and a configuration interaction method to compute the exciton fine structure and absorption coefficient. These core/shell structures exhibit type II confinement, which is more pronounced for the Si/Ge NC as a consequence of strain. The absorption coefficients of these NC's exhibit a single dominant peak, which has a much larger oscillator strength than the multipeaks found for pure Si and Ge NC's. The exciton lifetime in Si, Ge, and Ge/Si shows a small i:emperature dependence in the range 10-300 K, whereas in Si/Ge, the exciton lifetime decreases more than an order of magnitude in the same temperature range.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000301156500007 Publication Date 2012-01-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447;1932-7455; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 44 Open Access  
  Notes ; The authors acknowledge financial support from CNPq and the bilateral program between Flanders and Brazil and the Belgian Science Foundation (IAP). ; Approved Most recent IF: 4.536; 2012 IF: 4.814  
  Call Number UA @ lucian @ c:irua:113045 Serial 482  
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Author Avetisyan, A.A.; Partoens, B.; Peeters, F.M. doi  openurl
  Title Electric field tuning of the band gap in four layers of graphene with different stacking order Type P1 Proceeding
  Year 2012 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA Abbreviated Journal  
  Volume Issue Pages 84140-84148  
  Keywords P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract We investigated the effect of different stacking order of the four graphene layer system on the induced band gap when positively charged top and negatively charged back gates are applied to the system. A tight-binding approach within a self-consistent Hartree approximation is used to calculate the induced charges on the different graphene layers. We show that the electric field does not open an energy gap if the multilayer graphene system contains a trilayer part with the ABA Bernal stacking.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000303856600012 Publication Date 2012-01-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 8414 Series Issue Edition  
  ISSN ISBN Additional Links (up) UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), and the BelgianScience Policy (IAP). One of us (A.A.A.) was supported by a fellowship from the Belgian Federal Science Policy Office (BELSPO). ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:113046 Serial 886  
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Author Djotyan, A.P.; Avetisyan, A.A.; Hao, Y.L.; Peeters, F.M. doi  openurl
  Title Shallow donor near a semiconductor surface in the presence of locally spherical scanning tunneling microscope tip Type P1 Proceeding
  Year 2012 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA Abbreviated Journal  
  Volume Issue Pages 84140-84148  
  Keywords P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract We developed a variational approach to investigate the ground state energy and the extend of the wavefunction of a neutral donor located near a semiconductor surface in the presence of scanning tunneling microscope (STM) metallic tip. We apply the effective mass approximation and use a variational wavefunction that takes into account the influence of all image charges that arise due to the presence of a metallic tip. The behavior of the ground state energy when the tip approaches the semiconductor surface is investigated.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000303856600020 Publication Date 2012-01-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 8414 Series Issue Edition  
  ISSN ISBN Additional Links (up) UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (Belspo). ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:113047 Serial 2987  
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Author Bonroy, J.; Volckaert, M.; Seuntjens, P. doi  openurl
  Title Rapid automated measurement system for simultaneous determination of effective air-filled porosity and soil gas diffusivity Type A1 Journal article
  Year 2011 Publication Soil Science Society of America journal Abbreviated Journal  
  Volume 75 Issue 2 Pages 408-417  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The effective air-filled porosity and the gas diffusion coefficient are important soil parameters determining the success of soil bioremediation projects such as (bio)venting and (bio)sparging methods in combination with soil vapor extraction. We have developed a new method to sequentially measure the effective air-filled porosity and the soil gas diffusion coefficient of a soil sample. During the purging of the sample, a fast and accurate measurement of the effective air-filled porosity can be obtained. The subsequent diffusion measurement does not require a zero-O(2) concentration in the soil sample. The procedure further allows the calculation of the soil gas diffusion coefficient before an equilibrium O(2) concentration has been reached. The results are obtained by combining the data of the inlet and outlet compartment in a single equation. A stable reading is reached when the results for the inlet and outlet compartment coincide with the results from the combined equation. The analysis time is reduced by 89 to 96% compared with methods that run until an equilibrium concentration has been reached. Moreover, combining data from inlet and outlet compartments increases the accuracy of the diffusivity measurement by a factor of two compared with previous methods.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000288827000009 Publication Date 2012-09-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0361-5995 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:113062 Serial 8453  
Permanent link to this record
 

 
Author Peirs, J.; Verleysen, P.; Tirry, W.; Rabet, L.; Schryvers, D.; Degrieck, J. doi  openurl
  Title Dynamic shear localization in Ti6Al4V Type P1 Proceeding
  Year 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 (up) 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 Austing, D.G.; Payette, C.; Yu, G.; Gupta, J.A.; Aers, G.C.; Nair, S.V.; Partoens, B.; Amaha, S.; Tarucha, S. doi  openurl
  Title Characterization and modeling of single-particle energy levels and resonant currents in a coherent quantum dot mixer Type P1 Proceeding
  Year 2011 Publication AIP conference proceedings T2 – 30th International Conference on the Physics of Semiconductors (ICPS-30), JUL 25-30, 2010, Seoul, SOUTH KOREA Abbreviated Journal  
  Volume Issue Pages 1-2  
  Keywords P1 Proceeding; Condensed Matter Theory (CMT)  
  Abstract We characterize and model the single-particle energy level position and resonant current strength at a three-level crossing in a coherent mixer composed of two weakly coupled vertical quantum dots. In addition to clear anticrossing behavior, an otherwise strong resonance is completely extinguished at the center of the crossing. Despite the strong variation in energy level position and resonant current strength throughout the crossing region, the resonance widths and the sum of the branch currents are found to be approximately constant.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York Editor  
  Language Wos 000301053000453 Publication Date 2011-12-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 1399 Series Issue Edition  
  ISSN ISBN Additional Links (up) UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes ; ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:113070 Serial 314  
Permanent link to this record
 

 
Author Guttmann, P.; Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Umek, P.; Arcon, D.; Ewels, C.P.; Rehbein, S.; Heim, S.; Schneider, G. pdf  url
doi  openurl
  Title TXM-NEXAFS of TiO2-based nanostructures Type P1 Proceeding
  Year 2011 Publication AIP conference proceedings Abbreviated Journal  
  Volume 1365 Issue Pages 437-440  
  Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)  
  Abstract In this work, electronic properties of individual TiOx-pristine nanoribbons (NR) prepared by hydrothermal treatment of anatase TiO(2) micro-particles were studied using the HZB transmission x-ray microscope (TXM) at the BESSY II undulator beamline U41-FSGM. NEXAFS is ideally suited to study TiO(2)-based materials because both the O K-edge and Ti L-edge features are very sensitive to the local bonding environment, providing diagnostic information about the crystal structures and oxidation states of various forms of titanium oxides and sub-oxides. TXM-NEXAFS combines full-field x-ray microscopy with spectroscopy, allowing the study of the electronic structure of individual nanostructures with spatial resolution better than 25 nm and a spectral resolution of up to E/Delta E = 10000. The typical image field in TXM-NEXAFS measurements is about 10 mu m. 10 mu m, which is large compared to the individual nanoparticle. Therefore, one image stack already contains statistically significant data. In addition, the directional electric field vector ((E) over bar) of the x-rays can be used as a “search tool” for the direction of chemical bonds of the atom selected by its absorption edge.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York Editor  
  Language Wos 000298672400103 Publication Date 2011-09-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 2 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:113071 Serial 3789  
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Author Piñera, I.; Abreu, Y.; van Espen, P.; Diaz, A.; Leyva, A.; Cruz, C.M. openurl 
  Title Radiation damage evaluation on LYSO and LuYAP materials through Dpa calculation assisted by Monte Carlo method Type P1 Proceeding
  Year 2011 Publication IEEE conference record T2 – IEEE Nuclear Science Symposium/Medical Imaging Conference (NSS/MIC)/18th, International Workshop on Room-Temperature Semiconductor X-Ray and, Gamma-Ray Detectors, OCT 23-29, 2011, Valencia, SPAIN Abbreviated Journal  
  Volume Issue Pages 1609-1611  
  Keywords P1 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The aim of the present work is to study the radiation damage induced in LYSO and LuYAP crystals by the gamma radiation and the secondary electrons/positrons generated. The displacements per atom (dpa) distributions inside each material were calculated following the Monte Carlo assisted Classical Method (MCCM) introduced by the authors. As gamma sources were used Sc-44, Na-22 and V-48. Also the energy of gammas from the annihilation processes (511 keV) was included in the study. This procedure allowed studying the in-depth dpa distributions inside each crystal for all four sources. It was also possible to obtain the separate contribution from each atom to the total dpa. The LYSO crystals were found to receive more damage, mainly provoked by the displacements of silicon and oxygen atoms.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304755601169 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 978-1-4673-0120-6 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:113072 Serial 8447  
Permanent link to this record
 

 
Author Abreu, Y.; Cruz, C.M.; van Espen, P.; Piñera, I.; Leyva, A.; Cabal, A.E. openurl 
  Title Multiscale modeling of radiation damage and annealing in Si samples implanted with 57-Mn radioactive ions Type P1 Proceeding
  Year 2011 Publication IEEE conference record T2 – IEEE Nuclear Science Symposium/Medical Imaging Conference (NSS/MIC)/18th, International Workshop on Room-Temperature Semiconductor X-Ray and, Gamma-Ray Detectors, OCT 23-29, 2011, Valencia, SPAIN Abbreviated Journal  
  Volume Issue Pages 1754-1756  
  Keywords P1 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The radiation damage created in silicon materials by Mn-57 -> Fe-57 ion implantation has been studied and characterized by Mossbauer spectroscopy showing four main lines, assigned to: substitutional, interstitial and damaged configuration sites of the implanted ions. Nevertheless, the Mossbauer spectrum of Fe-57 in this materials remains with some ambiguous identification regarding the implantation configurations before and after annealing, specially the damaged configurations and its evolution. In the present work some possible implantation configurations are suggested and evaluated using a multiscale approach by Monte Carlo ion transport and electronic structure calculations within DFT. The proposed implantation environments were evaluated in terms of stability and the Fe-57 hyperfine parameters were calculated to establish the connections with the experimental observations. Good agreement was found between the experimental and the calculated hyperfine parameters for some configurations; suggesting which ones could be the implantation environments before and after sample annealing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304755601202 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 978-1-4673-0120-6 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:113073 Serial 8289  
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