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Author Borgatti, F.; Park, C.; Herpers, A.; Offi, F.; Egoavil, R.; Yamashita, Y.; Yang, A.; Kobata, M.; Kobayashi, K.; Verbeeck, J.; Panaccione, G.; Dittmann, R.;
  Title Chemical insight into electroforming of resistive switching manganite heterostructures Type A1 Journal article
  Year 2013 Publication Nanoscale Abbreviated Journal Nanoscale
  Volume 5 Issue 9 Pages 3954-3960
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract We have investigated the role of the electroforming process in the establishment of resistive switching behaviour for Pt/Ti/Pr0.5Ca0.5MnO3/SrRuO3 layered heterostructures (Pt/Ti/PCMO/SRO) acting as non-volatile Resistance Random Access Memories (RRAMs). Electron spectroscopy measurements demonstrate that the higher resistance state resulting from electroforming of as-prepared devices is strictly correlated with the oxidation of the top electrode Ti layer through field-induced electromigration of oxygen ions. Conversely, PCMO exhibits oxygen depletion and downward change of the chemical potential for both resistive states. Impedance spectroscopy analysis, supported by the detailed knowledge of these effects, provides an accurate model description of the device resistive behaviour. The main contributions to the change of resistance from the as-prepared (low resistance) to the electroformed (high resistance) states are respectively due to reduced PCMO at the boundary with the Ti electrode and to the formation of an anisotropic np junction between the Ti and the PCMO layers.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000317859400051 Publication Date (down) 2013-03-05
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.367 Times cited 40 Open Access
  Notes Vortex; Countatoms ECASJO_; Approved Most recent IF: 7.367; 2013 IF: 6.739
  Call Number UA @ lucian @ c:irua:108710UA @ admin @ c:irua:108710 Serial 348
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Author Smits, M.; Chan, C. kit; Tytgat, T.; Craeye, B.; Costarramone, N.; Lacombe, S.; Lenaerts, S.
  Title Photocatalytic degradation of soot deposition : self-cleaning effect on titanium dioxide coated cementitious materials Type A1 Journal article
  Year 2013 Publication Chemical engineering journal Abbreviated Journal Chem Eng J
  Volume 222 Issue Pages 411-418
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
  Abstract Diesel soot emissions deteriorate the appearance of architectural building materials by soot fouling. This soot deposition devalue the aesthetic value of the building. A solution to counteract this problem is applying titanium dioxide on building materials. TiO2 can provide air-purifying and self-cleaning properties due to its photocatalytic activity. In literature, photocatalytic soot oxidation is observed on glass or silicon substrates. However, degradation of soot by photocatalysis was not yet investigated on cementitious samples (mortar, concrete) although it is one of the most frequently used building materials. In this study, photocatalytic soot oxidation by means of TiO2 coated cementitious samples is addressed. The soot removal capacity of four types of TiO2 layers, coated on mortar samples, is evaluated by means of two detection methods. The first method is based on colorimetric measurements, while the second method uses digital image processing to calculate the area of soot coverage. The experimental data revealed that cementitious materials coated with commercially available TiO2 exhibited self-cleaning properties as it was found that all coated samples were able to remove soot. The P25 coating gave the best soot degradation performance, while the Eoxolit product showed the slowest soot degradation rate. In addition, gas chromatography measurements in a closed chamber experiment with P25 confirmed that complete mineralization of about 60% of the soot was obtained within 24 hours since CO2 was the sole observed oxidation product. Due to its realistic approach, this study proves that photocatalytic soot removal on TiO2 coated cementitious surfaces is possible in practice, which is an important step towards the practical application of self-cleaning building materials.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000319528900046 Publication Date (down) 2013-03-05
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1385-8947; 1873-3212 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.216 Times cited 43 Open Access
  Notes ; This work was supported by a PhD grant (M. Smits) from the University of Antwerp, a PhD grant (T. Tytgat) funded by the Institute of Innovation by Science and Technology in Flanders (IWT) and the exchange program Tournesol (Project T2012.05) financed by the Flemish government. ; Approved Most recent IF: 6.216; 2013 IF: 4.058
  Call Number UA @ admin @ c:irua:106519 Serial 5979
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Author Rossell, M.D.; Abakumov, A.M.; Ramasse, Q.M.; Erni, R.
  Title Direct evidence of stacking disorder in the mixed ionic-electronic conductor Sr4Fe6O12+\delta Type A1 Journal article
  Year 2013 Publication ACS nano Abbreviated Journal Acs Nano
  Volume 7 Issue 4 Pages 3078-3085
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Determining the structure-to-property relationship of materials becomes particularly challenging when the material under investigation is dominated by defects and structural disorder. Knowledge on the exact atomic arrangement at the defective structure is required to understand its influence on the functional properties. However, standard diffraction techniques deliver structural information that is averaged over many unit cells. In particular, information about defects and order-disorder phenomena is contained in the coherent diffuse scattering intensity which often is difficult to uniquely interpret. Thus, the examination of the local disorder in materials requires a direct method to study their structure on the atomic level with chemical sensitivity. Using aberration-corrected scanning transmission electron microscopy in combination with atomic-resolution electron energy-loss spectroscopy, we show that the controversial structural arrangement of the Fe2O2+delta layers in the mixed ionic-electronic conducting Sr4Fe6O12+delta perovskite can be unambiguously resolved. Our results provide direct experimental evidence for the presence of a nanomixture of “ordered” and “disordered” domains in an epitaxial Sr4Fe6O12+delta thin film. The most favorable arrangement is the disordered structure and is interpreted as a randomly occurring but well-defined local shift of the Fe-O chains in the Fe2O2+delta layers. By analyzing the electron energy-loss near-edge structure of the different building blocks in the Sr4Fe6O12+delta unit cell we find that the mobile holes in this mixed ionic-electronic conducting oxide are highly localized in the Fe2O2+delta layers, which are responsible for the oxide-ion conductivity. A possible link between disorder and oxygen-ion transport along the Fe2O2+delta layers is proposed by arguing that the disorder can effectively break the oxygen diffusion pathways.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000318143300021 Publication Date (down) 2013-03-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 13.942 Times cited 4 Open Access
  Notes Approved Most recent IF: 13.942; 2013 IF: 12.033
  Call Number UA @ lucian @ c:irua:108476 Serial 713
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Author Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M.
  Title Adsorption and absorption of boron, nitrogen, aluminum, and phosphorus on silicene : stability and electronic and phonon properties Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 8 Pages 085444-85448
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Ab initio calculations within the density-functional theory formalism are performed to investigate the chemical functionalization of a graphene-like monolayer of siliconsilicenewith B, N, Al, or P atoms. The structural, electronic, magnetic, and vibrational properties are reported. The most preferable adsorption sites are found to be valley, bridge, valley and hill sites for B, N, Al, and P adatoms, respectively. All the relaxed systems with adsorbed/substituted atoms exhibit metallic behavior with strongly bonded B, N, Al, and P atoms accompanied by an appreciable electron transfer from silicene to the B, N, and P adatom/substituent. The Al atoms exhibit opposite charge transfer, with n-type doping of silicene and weaker bonding. The adatoms/substituents induce characteristic branches in the phonon spectrum of silicene, which can be probed by Raman measurements. Using molecular dynamics, we found that the systems under study are stable up to at least T=500 K. Our results demonstrate that silicene has a very reactive and functionalizable surface.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315482900007 Publication Date (down) 2013-02-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 169 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107071 Serial 60
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Author Barba-Ortega, J.; Sardella, E.; Aguiar, J.A.; Peeters, F.M.
  Title Non-conventional vortex configurations in a mesoscopic flat disk Type A1 Journal article
  Year 2013 Publication Physica: C : superconductivity Abbreviated Journal Physica C
  Volume 487 Issue Pages 47-55
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The influence of superficial defects on the vortex configurations of a thin superconducting disk is investigated within the time dependent Ginzburg-Landau formalism. The free energy, magnetization, vorticity, and the Cooper pair density are calculated for both metastable and stable vortex configurations and different number of defects on its surface in the presence of an external magnetic field applied perpendicular to the disk area. We show that the competition between the confinement geometry and the geometric position of the defects leads to non-conventional vortex configurations which are not compatible with the symmetry of the sample geometry. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Amsterdam Editor
  Language Wos 000317743300009 Publication Date (down) 2013-02-27
  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 17 Open Access
  Notes ; This work was partially supported by the Brazilian agencies CNPq, CAPES, FACEPE (APQ 0589-105/08), FAPESP, CNPq-FWO bilateral project, and Colombian Agencies Colciencias and DIB. ; Approved Most recent IF: 1.404; 2013 IF: 1.110
  Call Number UA @ lucian @ c:irua:108486 Serial 2344
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Author Zhang, S.H.; Xu, W.; Badalyan, S.M.; Peeters, F.M.
  Title Piezoelectric surface acoustical phonon limited mobility of electrons in graphene on a GaAs substrate Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 7 Pages 075443-75445
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We study the mobility of Dirac fermions in monolayer graphene on a GaAs substrate, limited by the combined action of the extrinsic potential of piezoelectric surface acoustical phonons of GaAs (PA) and of the intrinsic deformation potential of acoustical phonons in graphene (DA). In the high-temperature (T) regime, the momentum relaxation rate exhibits the same linear dependence on T but different dependencies on the carrier density n, corresponding to the mobility mu proportional to 1 root n and 1/n, respectively for the PA and DA scattering mechanisms. In the low-T Bloch-Gruneisen regime, the mobility shows the same square-root density dependence mu proportional to root n, but different temperature dependencies mu proportional to T-3 and T-4, respectively for PA and DA phonon scattering. DOI: 10.1103/PhysRevB.87.075443
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315375200008 Publication Date (down) 2013-02-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 25 Open Access
  Notes ; This work was supported by the ESF-Eurocores program EuroGRAPHENE (CONGRAN project) and the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107655 Serial 2622
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Author Neek-Amal, M.; Beheshtian, J.; Shayeganfar, F.; Singh, S.K.; Los, J.H.; Peeters, F.M.
  Title Spiral graphone and one-sided fluorographene nanoribbons Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 7 Pages 075448-8
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The instability of a free-standing one-sided hydrogenated/fluorinated graphene nanoribbon, i.e., graphone/fluorographene, is studied using ab initio, semiempirical, and large-scale molecular dynamics simulations. Free-standing semi-infinite armchairlike hydrogenated/fluorinated graphene (AC-GH/AC-GF) and boatlike hydrogenated/fluorinated graphene (B-GH/B-GF) (nanoribbons which are periodic along the zigzag direction) are unstable and spontaneously transform into spiral structures. We find that rolled, spiral B-GH and B-GF are energetically more favorable than spiral AC-GH and AC-GF which is opposite to the double-sided flat hydrogenated/fluorinated graphene, i.e., graphane/fluorographene. We found that the packed, spiral structures exhibit an unexpected localized highest occupied molecular orbital and lowest occupied molecular orbital at the edges with increasing energy gap during rolling. These rolled hydrocarbon structures are stable beyond room temperature up to at least T = 1000 K within our simulation time of 1 ns. DOI: 10.1103/PhysRevB.87.075448
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315481800005 Publication Date (down) 2013-02-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 14 Open Access
  Notes ; We thank A. Sadeghi, M. R. Ejtehadi, and J. Amini for their useful comments. This work is supported by the ESF EuroGRAPHENE project CONGRAN and the Flemish Science Foundation (FWO-Vl). M.N.-A. is supported by a EU-Marie Curie IIF fellowship program Grant No. 299855. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107654 Serial 3106
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Author Saniz, R.; Partoens, B.; Peeters, F.M.
  Title Confinement effects on electron and phonon degrees of freedom in nanofilm superconductors : a Green function approach Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 6 Pages 064510-64513
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The Green function approach to the Bardeen-Cooper-Schrieffer theory of superconductivity is used to study nanofilms. We go beyond previous models and include effects of confinement on the strength of the electron-phonon coupling as well as on the electronic spectrum and on the phonon modes. Within our approach, we find that in ultrathin films, confinement effects on the electronic screening become very important. Indeed, contrary to what has been advanced in recent years, the sudden increases of the density of states when new bands start to be occupied as the film thickness increases, tend to suppress the critical temperature rather than to enhance it. On the other hand, the increase of the number of phonon modes with increasing number of monolayers in the film leads to an increase in the critical temperature. As a consequence, the superconducting critical parameters in such nanofilms are determined by these two competing effects. Furthermore, in sufficiently thin films, the condensate consists of well-defined subcondensates associated with the occupied bands, each with a distinct coherence length. The subcondensates can interfere constructively or destructively giving rise to an interference pattern in the Cooper pair probability density.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315374100009 Publication Date (down) 2013-02-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 6 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). R.S. thanks M. R. Norman, B. Soree, and L. Komendova for useful comments. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107072 Serial 487
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Author Arsoski, V.V.; Tadić, M.Z.; Peeters, F.M.
  Title Strain and band-mixing effects on the excitonic Aharonov-Bohm effect in In(Ga)As/GaAs ringlike quantum dots Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 8 Pages 085314-14
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Neutral excitons in strained axially symmetric In(Ga)As/GaAs quantum dots with a ringlike shape are investigated. Similar to experimental self-assembled quantum rings, the analyzed quantum dots have volcano-like shapes. The continuum mechanical model is employed to determine the strain distribution, and the single-band envelope function approach is adopted to compute the electron states. The hole states are determined by the axially symmetric multiband Luttinger-Kohn Hamiltonian, and the exciton states are obtained from an exact diagonalization. We found that the presence of the inner layer covering the ring opening enhances the excitonic Aharonov-Bohm (AB) oscillations. The reason is that the hole becomes mainly localized in the inner part of the quantum dot due to strain, whereas the electron resides mainly inside the ring-shaped rim. Interestingly, larger AB oscillations are found in the analyzed quantum dot than in a fully opened quantum ring of the same width. Comparison with the unstrained ringlike quantum dot shows that the amplitude of the excitonic Aharonov-Bohm oscillations are almost doubled in the presence of strain. The computed oscillations of the exciton energy levels are comparable in magnitude to the oscillations measured in recent experiments. DOI: 10.1103/PhysRevB.87.085314
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315278000003 Publication Date (down) 2013-02-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 18 Open Access
  Notes ; This work was supported by the EU NoE: SANDiE, the Ministry of Education, Science, and Technological Development of Serbia, and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107656 Serial 3165
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Author Cataldo, M.; Evangelista, H.; Simões, J.C.; Godoi, R.H.M.; Simmonds, I.; Hollanda, M.H.; Wainer, I.; Aquino, F.; Van Grieken, R.
  Title Mineral dust variability in central West Antarctica associated with ozone depletion Type A1 Journal article
  Year 2013 Publication Atmospheric chemistry and physics Abbreviated Journal
  Volume 13 Issue 4 Pages 2165-2175
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract We present here data of mineral dust variability retrieved from an ice core of the central West Antarctic, spanning the last five decades. Main evidence provided by the geochemical analysis is that northerly air mass incursions to the coring site, tracked by insoluble dust microparticles, have declined over the past 50 yr. This result contrasts with dust records from ice cores reported to the coastal West Antarctic that show increases since mid-20th century. We attribute this difference to regional climatic changes due to the ozone depletion and its implications to westerly winds. We found that the diameters of insoluble microparticles in the central West Antarctica ice core are significantly correlated with cyclone depth (energy) and wind intensity around Antarctica.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315406600027 Publication Date (down) 2013-02-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1680-7316; 1680-7324 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:105832 Serial 8250
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Author Yusupov, M.; Bogaerts, A.; Huygh, S.; Snoeckx, R.; van Duin, A.C.T.; Neyts, E.C.
  Title Plasma-induced destruction of bacterial cell wall components : a reactive molecular dynamics simulation 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 11 Pages 5993-5998
  Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Nonthermal atmospheric pressure plasmas are gaining increasing attention for biomedical applications. However, very little fundamental information on the interaction mechanisms between the plasma species and biological cells is currently available. We investigate the interaction of important plasma species, such as OH, H2O2, O, O3, as well as O2 and H2O, with bacterial peptidoglycan by means of reactive molecular dynamics simulations, aiming for a better understanding of plasma disinfection. Our results show that OH, O, O3, and H2O2 can break structurally important bonds of peptidoglycan (i.e., CO, CN, or CC bonds), which consequently leads to the destruction of the bacterial cell wall. The mechanisms behind these breakups are, however, dependent on the impinging plasma species, and this also determines the effectiveness of the cell wall destruction.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000316773000056 Publication Date (down) 2013-02-23
  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 59 Open Access
  Notes Approved Most recent IF: 4.536; 2013 IF: 4.835
  Call Number UA @ lucian @ c:irua:107154 Serial 2636
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Author Grujić, M.; Tadić, M.; Peeters, F.M.
  Title Antiferromagnetism in hexagonal graphene structures : rings versus dots Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 8 Pages 085434-85436
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Themean-field Hubbard model is used to investigate the formation of the antiferromagnetic phase in hexagonal graphene rings with inner zigzag edges. The outer edge of the ring was taken to be either zigzag or armchair, and we found that both types of structures can have a larger antiferromagnetic interaction as compared with hexagonal dots. This difference could be partially ascribed to the larger number of zigzag edges per unit area in rings than in dots. Furthermore, edge states localized on the inner ring edge are found to hybridize differently than the edge states of dots, which results in important differences in the magnetism of graphene rings and dots. The largest staggered magnetization is found when the outer edge has a zigzag shape. However, narrow rings with armchair outer edge are found to have larger staggered magnetization than zigzag hexagons. The edge defects are shown to have the least effect on magnetization when the outer ring edge is armchair shaped. DOI: 10.1103/PhysRevB.87.085434
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315146600005 Publication Date (down) 2013-02-20
  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 the EuroGRAPHENE programme of the ESF (project CONGRAN), the Serbian Ministry of Education, Science, and Technological Development, and the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107661 Serial 137
Permanent link to this record
 

 
Author Sahin, H.; Peeters, F.M.
  Title Adsorption of alkali, alkaline-earth, and 3d transition metal atoms on silicene Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 8 Pages 085423-85429
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The adsorption characteristics of alkali, alkaline-earth, and transition metal adatoms on silicene, a graphene-like monolayer structure of silicon are analyzed by means of first-principles calculations. In contrast to graphene, interaction between the metal atoms and the silicene surface is quite strong due to its highly reactive buckled hexagonal structure. In addition to structural properties, we also calculate the electronic band dispersion, net magnetic moment, charge transfer, work function, and dipole moment of the metal adsorbed silicene sheets. Alkali metals, Li, Na, and K, adsorb to hollow sites without any lattice distortion. As a consequence of the significant charge transfer from alkalis to silicene, metalization of silicene takes place. Trends directly related to atomic size, adsorption height, work function, and dipole moment of the silicene/alkali adatom system are also revealed. We found that the adsorption of alkaline-earth metals on silicene is entirely different from their adsorption on graphene. The adsorption of Be, Mg, and Ca turns silicene into a narrow gap semiconductor. Adsorption characteristics of eight transition metals Ti, V, Cr, Mn, Fe, Co, Mo, and W are also investigated. As a result of their partially occupied d orbital, transition metals show diverse structural, electronic, and magnetic properties. Upon the adsorption of transition metals, depending on the adatom type and atomic radius, the system can exhibit metal, half-metal, and semiconducting behavior. For all metal adsorbates, the direction of the charge transfer is from adsorbate to silicene, because of its high surface reactivity. Our results indicate that the reactive crystal structure of silicene provides a rich playground for functionalization at nanoscale. DOI: 10.1103/PhysRevB.87.085423
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315146500008 Publication Date (down) 2013-02-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 281 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. is supported by a FWO Pegasus Marie Curie Fellowship. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107663 Serial 62
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Author Masir, M.R.; Peeters, F.M.
  Title Scattering of Dirac electrons by a random array of magnetic flux tubes Type A1 Journal article
  Year 2013 Publication Journal of computational electronics Abbreviated Journal J Comput Electron
  Volume 12 Issue 2 Pages 115-122
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The scattering of two-dimensional (2D) massless electrons as presented in graphene in the presence of a random array of circular magnetic flux tubes is investigated. The momentum relaxation time and the Hall factor are obtained using optical theorem techniques for scattering. Electrons with energy close to those of the Landau levels of the flux tubes exhibit resonant scattering and have a long life-time to reside inside the magnetic flux tube. These resonances appear as sharp structures in the Hall factor and the magneto-resistance.
  Address
  Corporate Author Thesis
  Publisher Place of Publication S.l. Editor
  Language Wos 000320044900007 Publication Date (down) 2013-02-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1569-8025;1572-8137; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 1.526 Times cited 2 Open Access
  Notes ; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN and the Flemish Science Foundation (FWO-Vl). We acknowledge fruitful discussions with A. Matulis. ; Approved Most recent IF: 1.526; 2013 IF: 1.372
  Call Number UA @ lucian @ c:irua:109615 Serial 2950
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Author Li, B.; Djotyan, A.P.; Hao, Y.L.; Avetisyan, A.A.; Peeters, F.M.
  Title Effect of a perpendicular magnetic field on the shallow donor states near a semiconductor-metal interface Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 7 Pages 075313-75319
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We investigate the influence of an external perpendicular magnetic field on the lowest-energy states of an electron bound to a donor which is located near a semiconductor-metal interface. The problem is treated within the effective mass approach and the lowest-energy states are obtained through (1) the “numerically exact” finite element method, and (2) a variational approach using a trial wave function where all image charges that emerge due to the presence of the metallic gate are taken into account. The trial wave functions are constructed such that they reduce to an exponential behavior for sufficiently small magnetic fields and become Gaussian for intermediate and large magnetic fields. The average electron-donor distance can be controlled by the external magnetic field. We find that the size of the 2p(z) state depends strongly on the magnetic field when the donor is close to the interface, showing a nonmonotonic behavior, in contrast with the ground and the other excited states. DOI: 10.1103/PhysRevB.87.075313
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000314874800017 Publication Date (down) 2013-02-13
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 1 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107664 Serial 793
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Author Abakumov, A.M.; Batuk, M.; Tsirlin, A.A.; Tyablikov, O.A.; Sheptyakov, D.V.; Filimonov, D.S.; Pokholok, K.V.; Zhidal, V.S.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.;
  Title Structural and magnetic phase transitions in the AnBnO3n-2 anion-deficient perovskites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 Type A1 Journal article
  Year 2013 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
  Volume 52 Issue 14 Pages 7834-7843
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Novel anion-deficient perovskite-based ferrites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 were synthesized by solid-state reaction in air. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 belong to the perovskite-based AnBnO3n2 homologous series with n = 5 and 6, respectively, with a unit cell related to the perovskite subcell ap as ap√2 × ap × nap√2. Their structures are derived from the perovskite one by slicing it with 1/2[110]p(1̅01)p crystallographic shear (CS) planes. The CS operation results in (1̅01)p-shaped perovskite blocks with a thickness of (n 2) FeO6 octahedra connected to each other through double chains of edge-sharing FeO5 distorted tetragonal pyramids which can adopt two distinct mirror-related configurations. Ordering of chains with a different configuration provides an extra level of structure complexity. Above T ≈ 750 K for Pb2Ba2BiFe5O13 and T ≈ 400 K for Pb1.5Ba2.5Bi2Fe6O16 the chains have a disordered arrangement. On cooling, a second-order structural phase transition to the ordered state occurs in both compounds. Symmetry changes upon phase transition are analyzed using a combination of superspace crystallography and group theory approach. Correlations between the chain ordering pattern and octahedral tilting in the perovskite blocks are discussed. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 undergo a transition into an antiferromagnetically (AFM) ordered state, which is characterized by a G-type AFM ordering of the Fe magnetic moments within the perovskite blocks. The AFM perovskite blocks are stacked along the CS planes producing alternating FM and AFM-aligned FeFe pairs. In spite of the apparent frustration of the magnetic coupling between the perovskite blocks, all n = 4, 5, 6 AnFenO3n2 (A = Pb, Bi, Ba) feature robust antiferromagnetism with similar Néel temperatures of 623632 K.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Easton, Pa Editor
  Language Wos 000322087100006 Publication Date (down) 2013-02-13
  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 10 Open Access
  Notes Countatoms Approved Most recent IF: 4.857; 2013 IF: 4.794
  Call Number UA @ lucian @ c:irua:109213 Serial 3196
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Author Lizin, S.; Leroy, J.; Delvenne, C.; Dijk, M.; De Schepper, E.; Van Passel, S.
  Title A patent landscape analysis for organic photovoltaic solar cells : identifying the technology's development phase Type A1 Journal article
  Year 2013 Publication Renewable Energy Abbreviated Journal Renew Energ
  Volume 57 Issue Pages 5-11
  Keywords A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM)
  Abstract Organic photovoltaics (OPV) have developed into a vast research area. Progress in various directions has made it difficult to monitor the technology's precise development state. We offer a patent landscape analysis over all OPV devices, their substrates and encapsulation materials to provide an overview of patenting activity from a historical, organizational, geographical and technological point of view. Such an exercise is instrumental for private companies and research institutes aiming at both internal or external technology creation. We discuss our findings in the context of the Industrial Life Cycle model and find OPV still residing in the fluid technology development phase. Technology development is still following an exponential growth path, with the majority of patents coming from the Asian continent and in general private companies. For devices, the main technological focus can be traced back to the “H01L-031” international patent classification (IPC) main group. For the queried substrates, the most attention has gone to glass, but paper and textile have drawn significant interest too. Finally, encapsulation is found to be a less mature research field given the smaller number of patent families. The latter shows that the technology has not matured to the level where processing is carried out on a commercial scale. (C) 2013 Elsevier Ltd. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000319025000002 Publication Date (down) 2013-02-13
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0960-1481 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.357 Times cited 18 Open Access
  Notes ; The authors are much obliged to INTERREG for their financial support of the ORGANEXT project (www.organext.org), without which it would have been impossible to conduct this research. ; Approved Most recent IF: 4.357; 2013 IF: 3.361
  Call Number UA @ admin @ c:irua:127551 Serial 6143
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Author Villegas, C.E.P.; Tavares, M.R.S.; Hai, G.-Q.; Peeters, F.M.
  Title Sorting the modes contributing to guidance in strain-induced graphene waveguides Type A1 Journal article
  Year 2013 Publication New journal of physics Abbreviated Journal New J Phys
  Volume 15 Issue Pages 023015-11
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We propose a simple way of probing the number of modes contributing to the channeling in graphene waveguides which are formed by a gauge potential produced by mechanical strain. The energy mode structure for both homogeneous and non-homogeneous strain regimes is carefully studied using the continuum description of the Dirac equation. We found that high strain values privilege negative (instead of positive) group velocities throughout the guidance, sorting the types of modes flowing through it. We also show how the effect of a substrate-induced gap competes against the strain.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Bristol Editor
  Language Wos 000314868000002 Publication Date (down) 2013-02-08
  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 7 Open Access
  Notes ; This work was supported by FAPESP, CNPq and the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 3.786; 2013 IF: 3.671
  Call Number UA @ lucian @ c:irua:107667 Serial 3056
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Author Verheyen, E.; Jo, C.; Kurttepeli, M.; Vanbutsele, G.; Gobechiya, E.; Korányi, T.I.; Bals, S.; Van Tendeloo, G.; Ryoo, R.; Kirschhock, C.E.A.; Martens, J.A.;
  Title Molecular shape-selectivity of MFI zeolite nanosheets in n-decane isomerization and hydrocracking Type A1 Journal article
  Year 2013 Publication Journal of catalysis Abbreviated Journal J Catal
  Volume 300 Issue Pages 70-80
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract MFI zeolite nanosheets with thickness of 2 and 8 nm were synthesized, transformed into bifunctional catalysts by loading with platinum and tested in n-decane isomerization and hydrocracking. Detailed analysis of skeletal isomers and hydrocracked products revealed that the MFI nanosheets display transition-state shape-selectivity similar to bulk MFI zeolite crystals. The suppressed formation of bulky skeletal isomers and C5 cracking products are observed both in the nanosheets and the bulk crystals grown in three dimensions. This is typical for restricted transition-state shape-selectivity, characteristic for the MFI type pores. It is a first clear example of transition-state shape-selectivity inside a zeolitic nanosheet. Owing to the short diffusion path across the sheets, expression of diffusion-based discrimination of reaction products in the MFI nanosheets was limited. The 2-methylnonane formation among monobranched C10 isomers and 2,7-dimethyloctane among dibranched C10 isomers, which in MFI zeolite are favored by product diffusion, was much less favored on the nanosheets compared to the reference bulk ZSM-5 material.
  Address
  Corporate Author Thesis
  Publisher Place of Publication San Diego, Calif. Editor
  Language Wos 000317558000009 Publication Date (down) 2013-02-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0021-9517; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.844 Times cited 121 Open Access
  Notes Methusalem; IAP; Countatoms Approved Most recent IF: 6.844; 2013 IF: 6.073
  Call Number UA @ lucian @ c:irua:106186 Serial 2181
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Author Terzano, R.; Alfeld, M.; Janssens, K.; Vekemans, B.; Schoonjans, T.; Vincze, L.; Tomasi, N.; Pinton, R.; Cesco, S.
  Title Spatially resolved (semi)quantitative determination of iron (Fe) in plants by means of synchrotron micro X-ray fluorescence Type A1 Journal article
  Year 2013 Publication Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem
  Volume 405 Issue 10 Pages 3341-3350
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Iron (Fe) is an essential element for plant growth and development; hence determining Fe distribution and concentration inside plant organs at the microscopic level is of great relevance to better understand its metabolism and bioavailability through the food chain. Among the available microanalytical techniques, synchrotron mu-XRF methods can provide a powerful and versatile array of analytical tools to study Fe distribution within plant samples. In the last years, the implementation of new algorithms and detection technologies has opened the way to more accurate (semi)quantitative analyses of complex matrices like plant materials. In this paper, for the first time the distribution of Fe within tomato roots has been imaged and quantified by means of confocal mu-XRF and exploiting a recently developed fundamental parameter-based algorithm. With this approach, Fe concentrations ranging from few hundreds of ppb to several hundreds of ppm can be determined at the microscopic level without cutting sections. Furthermore, Fe (semi)quantitative distribution maps were obtained for the first time by using two opposing detectors to collect simultaneously the XRF radiation emerging from both sides of an intact cucumber leaf.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000316338700033 Publication Date (down) 2013-02-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.431 Times cited 27 Open Access
  Notes ; Research was supported by grants from Italian MIUR (FIRB-Programma “Futuro in Ricerca”) and Free University of Bolzano (TN5046 and TN5056). Synchrotron experiments at HASY-LAB were financially supported by the European Community Research Infrastructure Action under the FP6 “Structuring the European Research Area” Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). Matthias Alfeld receives a Ph.D. fellowship of the Research Foundation-Flanders (FWO). We thank Karen Rickers-Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; Approved Most recent IF: 3.431; 2013 IF: 3.578
  Call Number UA @ admin @ c:irua:108261 Serial 5838
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Author Batuk, M.; Batuk, D.; Tsirlin, A.A.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.
  Title Homologous series of layered perovskites An+1BnO3n-1Cl : crystal and magnetic structure of a new oxychloride Pb4BiFe4O11Cl Type A1 Journal article
  Year 2013 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
  Volume 52 Issue 4 Pages 2208-2218
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The nuclear and magnetic structure of a novel oxychloride Pb4BiFe4O11Cl has been studied over the temperature range 1.5700 K using a combination of transmission electron microscopy and synchrotron and neutron powder diffraction [space group P4/mbm, a = 5.5311(1) Å, c = 19.586(1) Å, T = 300 K]. Pb4BiFe4O11Cl is built of truncated (Pb,Bi)3Fe4O11 quadruple perovskite blocks separated by CsCl-type (Pb,Bi)2Cl slabs. The perovskite blocks consist of two layers of FeO6 octahedra located between two layers of FeO5 tetragonal pyramids. The FeO6 octahedra rotate about the c axis, resulting in a √2ap × √2ap × c superstructure. Below TN = 595(17) K, Pb4BiFe4O11Cl adopts a G-type antiferromagnetic structure with the iron magnetic moments confined to the ab plane. The ordered magnetic moments at 1.5 K are 3.93(3) and 3.62(4) μB on the octahedral and square-pyramidal iron sites, respectively. Pb4BiFe4O11Cl can be considered a member of the perovskite-based An+1BnO3n1Cl homologous series (A = Pb/Bi; B = Fe) with n = 4. The formation of a subsequent member of the series with n = 5 is also demonstrated.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Easton, Pa Editor
  Language Wos 000315255200067 Publication Date (down) 2013-02-05
  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 6 Open Access
  Notes Countatoms Approved Most recent IF: 4.857; 2013 IF: 4.794
  Call Number UA @ lucian @ c:irua:106185 Serial 1486
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Author Zhu, J.-J.; Badalyan, S.M.; Peeters, F.M.
  Title Plasmonic excitations in Coulomb-coupled N-layer graphene structures Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 8 Pages 085401-85408
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We study Dirac plasmons and their damping in spatially separated N-layer graphene structures at finite doping and temperatures. The plasmon spectrum consists of one optical excitation with square-root dispersion and N – 1 acoustical excitations with linear dispersion, which are undamped at zero temperature and finite doping within a triangular energy region outside the electron-hole continuum. In the long-wavelength limit the energy and weight of the optical plasmon modes increase, respectively, as the square root and linearly with N in agreement with recent experimental findings. The energy and weight of the upper-lying acoustical branches also increase with N. This increase is strongest for the uppermost acoustical mode, and we find that its energy can exceed at some value of momentum the plasmon energy in an individual graphene sheet. Meanwhile, the energy of the low-lying acoustical branches decreases weakly with N as compared with the single acoustical mode in double-layer graphene structures. Our numerical calculations provide a detailed understanding of the overall behavior of the wave-vector dependence of the optical and acoustical multilayer plasmon modes and show how their dispersion and damping are modified as a function of temperature, interlayer spacing, and inlayer carrier density in (un)balanced graphene multilayer structures. DOI: 10.1103/PhysRevB.87.085401
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000314682900005 Publication Date (down) 2013-02-05
  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 59 Open Access
  Notes ; This work was supported by the ESF-Eurocores program EuroGRAPHENE (CONGRAN project) and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107671 Serial 2645
Permanent link to this record
 

 
Author Hellar-Kihampa, H.; De Wael, K.; Lugwisha, E.; Govindan, M.; Covaci, A.; Van Grieken, R.
  Title Spatial monitoring of organohalogen compounds in surface water and sediments of a rural-urban river basin in Tanzania Type A1 Journal article
  Year 2013 Publication The science of the total environment Abbreviated Journal Sci Total Environ
  Volume 447 Issue Pages 186-197
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
  Abstract The presence of persistent organic pollutants in Tanzanian environment is not well monitored despite the existing pollution potential from a number of sources. In this study, we investigated for the first time, the concentration profiles of different organohalogen compounds such as organochlorine pesticide residues (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in environmental samples (water and sediments) from the Pangani river basin (PRB). The PRB is one of the largest drainage basins in Tanzania, with its watershed exposed to multiple input sources of trace organic contaminants. Surface water and sediments were sampled from 12 representative stations of diverse characteristics and land-use practices, in three distinct seasons, and extracted by liquidliquid and Soxhlet extraction methods, respectively. Water samples were analyzed by GC-ECD for OCPs only, while sediment samples were analyzed for OCPs, PCBs and PBDEs by GC/MS. Seven compounds, dominated by HCH isomers (5104460 pg/L) and DDT analogs (1601460 pg/L),were detected in the water samples. These concentrations are far below the WHO guidelines for drinking water quality. A total of 42 compounds (8 OCPs, 28 PCB congeners and 6 PBDE congeners) were detected in the sediment samples. Their respective total concentration ranges were 24510,230; 35711,000 and 382175 pg/g dry weight. The spatial distribution patterns and Hierarchical Cluster Analysis reflected the impact of historical agricultural usage in sugarcane plantations (OCPs), and urbanization (PCBs and PBDEs). Risk assessment using sediment quality guidelines indicated no ecotoxicological risks. The results we have found provide preliminary data on levels of the organic contaminants in Pangani river basin as a new insight on the environmental quality of the area.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000317538100022 Publication Date (down) 2013-02-05
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0048-9697 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.9 Times cited 42 Open Access
  Notes ; This research project was funded by the International Foundation for Science (IFS, Project Number W/4945-1). The authors wish to acknowledge the contribution of the Pangani Basin Water Office (PBWO) in Moshi, Tanzania; especially Ms. Arafa Maggidi in provision of valuable information and assistance with the sampling campaigns, and Salim Lyimo in mapping of the study area. The contributions of Mr. Peter Machibya of the Department of Geology, University of Dar es Salaam, Tanzania in sediment characterization; and Mr. Emmanuel Gwae, of the Government Chemists Laboratory Agency (GCLA) Dar es Salaam, Tanzania, for instrumental analysis of the water samples, are highly appreciated. Harieth Hellar-Kihampa acknowledges financial support from the Belgian Technical Agency (BTC). Govindan Malarvannan and Adrian Covaci acknowledge financial support from the University of Antwerp. ; Approved Most recent IF: 4.9; 2013 IF: 3.163
  Call Number UA @ admin @ c:irua:105260 Serial 5836
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Author Abakumov, A.M.; Batuk, D.; Tsirlin, A.A.; Prescher, C.; Dubrovinsky, L.; Sheptyakov, D.V.; Schnelle, W.; Hadermann, J.; Van Tendeloo, G.
  Title Frustrated pentagonal Cairo lattice in the non-collinear antiferromagnet Bi4Fe5O13F Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 2 Pages 024423-24429
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract We report on the crystal structure and magnetism of the iron-based oxyfluoride Bi4Fe5O13F, a material prototype of the Cairo pentagonal spin lattice. The crystal structure of Bi4Fe5O13F is determined by a combination of neutron diffraction, synchrotron x-ray diffraction, and transmission electron microscopy. It comprises layers of FeO6 octahedra and FeO4 tetrahedra forming deformed pentagonal units. The topology of these layers resembles a pentagonal least-perimeter tiling, which is known as the Cairo lattice. This topology gives rise to frustrated exchange couplings and underlies a sequence of magnetic transitions at T-1 = 62 K, T-2 = 71 K, and T-N = 178 K, as determined by thermodynamic measurements and neutron diffraction. Below T-1, Bi4Fe5O13F forms a fully ordered non-collinear antiferromagnetic structure, whereas the magnetic state between T-1 and T-N may be partially disordered according to the sizable increase in the magnetic entropy at T-1 and T-2. Bi4Fe5O13F reveals unanticipated magnetic transitions on the pentagonal Cairo spin lattice and calls for a further work on finite-temperature properties of this strongly frustrated spin model. DOI: 10.1103/PhysRevB.87.024423
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000314224800002 Publication Date (down) 2013-02-01
  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 17 Open Access
  Notes Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107688 Serial 1293
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Author Subban, C.V.; Ati, M.; Rousse, G.; Abakumov, A.M.; Van Tendeloo, G.; Janot, R.; Tarascon, J.-M.
  Title Preparation, structure, and electrochemistry of layered polyanionic hydroxysulfates : LiMSO4OH (M = Fe, Co, Mn) electrodes for Li-Ion batteries Type A1 Journal article
  Year 2013 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
  Volume 135 Issue 9 Pages 3653-3661
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The Li-ion rechargeable battery, due to its high energy density, has driven remarkable advances in portable electronics. Moving toward more sustainable electrodes could make this technology even more attractive to large-volume applications. We present here a new family of 3d-metal hydroxysulfates of general formula LiMSO4OH (M = Fe, Co, and Mn) among which (i) LiFeSO4OH reversibly releases 0.7 Li+ at an average potential of 3.6 V vs Li+/Li-0, slightly higher than the potential of currently lauded LiFePO4 (3.45 V) electrode material, and (ii) LiCoSO4OH shows a redox activity at 4.7 V vs Li+/Li-0. Besides, these compounds can be easily made at temperatures near 200 degrees C via a synthesis process that enlists a new intermediate phase of composition M-3(SO4)(2)(OH)(2) (M = Fe, Co, Mn, and Ni), related to the mineral caminite. Structurally, we found that LiFeSO4OH is a layered phase unlike the previously reported 3.2 V tavorite LiFeSO4OH. This work should provide an impetus to experimentalists for designing better electrolytes to fully tap the capacity of high-voltage Co-based hydroxysulfates, and to theorists for providing a means to predict the electrochemical redox activity of two polymorphs.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000315936700056 Publication Date (down) 2013-02-01
  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 53 Open Access
  Notes Approved Most recent IF: 13.858; 2013 IF: 11.444
  Call Number UA @ lucian @ c:irua:108283 Serial 2708
Permanent link to this record
 

 
Author Clima, S.; Kaczer, B.; Govoreanu, B.; Popovici, M.; Swerts, J.; Verhulst, A.S.; Jurczak, M.; De Gendt, S.; Pourtois, G.
  Title Determination of ultimate leakage through rutile TiO2 and tetragonal ZrO2 from ab initio complex band calculations Type A1 Journal article
  Year 2013 Publication IEEE electron device letters Abbreviated Journal Ieee Electr Device L
  Volume 34 Issue 3 Pages 402-404
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract First-principle complex band structures have been computed for rutile TiO2 and tetragonal ZrO2 insulating materials that are of current technological relevance to dynamic random accessmemorymetal-insulator-metal (MIM) capacitors. From the magnitude of the complex wave vectors in different orientations, the most penetrating orientations have been identified. Tunneling effective masses m(tunnel) have been extracted, are shown to be a crucial parameter for the intrinsic leakage, and are identified to be an important parameter in further scaling of MIM capacitors.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315723000024 Publication Date (down) 2013-01-31
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0741-3106;1558-0563; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.048 Times cited 3 Open Access
  Notes Approved Most recent IF: 3.048; 2013 IF: 3.023
  Call Number UA @ lucian @ c:irua:108295 Serial 680
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Author Houssa, M.; van den Broek, B.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
  Title An electric field tunable energy band gap at silicene/(0001) ZnS interfaces Type A1 Journal article
  Year 2013 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 15 Issue 11 Pages 3702-3705
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract The interaction of silicene, the silicon counterpart of graphene, with (0001) ZnS surfaces is investigated theoretically, using first-principles simulations. The charge transfer occurring at the silicene/(0001) ZnS interface leads to the opening of an indirect energy band gap of about 0.7 eV in silicene. Remarkably, the nature (indirect or direct) and magnitude of the energy band gap of silicene can be controlled by an external electric field: the energy gap is predicted to become direct for electric fields larger than about 0.5 V angstrom(-1), and the direct energy gap decreases approximately linearly with the applied electric field. The predicted electric field tunable energy band gap of the silicene/(0001) ZnS interface is very promising for its potential use in nanoelectronic devices.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000315165100002 Publication Date (down) 2013-01-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076;1463-9084; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 74 Open Access
  Notes Approved Most recent IF: 4.123; 2013 IF: 4.198
  Call Number UA @ lucian @ c:irua:107702 Serial 94
Permanent link to this record
 

 
Author Esfahani, D.N.; Covaci, L.; Peeters, F.M.
  Title Field effect on surface states in a doped Mott-insulator thin film Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 3 Pages 035131-35136
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Surface effects of a doped thin film made of a strongly correlated material are investigated both in the absence and presence of a perpendicular electric field. We use an inhomogeneous Gutzwiller approximation for a single-band Hubbard model in order to describe correlation effects. For low doping, the bulk value of the quasiparticle weight is recovered exponentially deep into the slab, but with increasing doping, additional Friedel oscillations appear near the surface. We show that the inverse correlation length has a power-law dependence on the doping level. In the presence of an electrical field, considerable changes in the quasiparticle weight can be realized throughout the system. We observe a large difference (as large as five orders of magnitude) in the quasiparticle weight near the opposite sides of the slab. This effect can be significant in switching devices that use the surface states for transport. DOI: 10.1103/PhysRevB.87.035131
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000313941000001 Publication Date (down) 2013-01-29
  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 4 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:110086 Serial 1190
Permanent link to this record
 

 
Author Zarenia, M.; Pereira, J.M., Jr.; Peeters, F.M.; Farias, G.A.
  Title Snake states in graphene quantum dots in the presence of a p-n junction Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 3 Pages 035426
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We investigate the magnetic interface states of graphene quantum dots that contain p-n junctions. Within a tight-binding approach, we consider rectangular quantum dots in the presence of a perpendicular magnetic field containing p-n as well as p-n-p and n-p-n junctions. The results show the interplay between the edge states associated with the zigzag terminations of the sample and the snake states that arise at the p-n junction due to the overlap between electron and hole states at the potential interface. Remarkable localized states are found at the crossing of the p-n junction with the zigzag edge having a dumb-bell-shaped electron distribution. The results are presented as a function of the junction parameters and the applied magnetic flux. DOI: 10.1103/PhysRevB.87.035426
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000313941000003 Publication Date (down) 2013-01-29
  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 16 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-VI), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CONGRAN), the Brazilian agency CNPq (Pronex), and the bilateral projects between Flanders and Brazil and the collaboration project FWO-CNPq. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:110087 Serial 3048
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Author Alfeld, M.; van der Snickt, G.; Vanmeert, F.; Janssens, K.; Dik, J.; Appel, K.; van der Loeff, L.; Chavannes, M.; Meedendorp, T.; Hendriks, E.
  Title Scanning XRF investigation of a Flower Still Life and its underlying composition from the collection of the Kröller-Muller Museum Type A1 Journal article
  Year 2013 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
  Volume 111 Issue 1 Pages 165-175
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000316075700020 Publication Date (down) 2013-01-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 1.455 Times cited 35 Open Access
  Notes ; This research was supported by the SSD program of BELSPO, Brussels (project S2-ART). Results are also presented here from Gemeenschappelijke Onderzoeksactie (GOA) 'XANES meets ELNES' (Research Fund, University of Antwerp, Belgium) and from Fonds voor Wetenschappelijk Onderzoek (FWO) (Brussels, Belgium) project Nos. G.0704.08 and G.01769.09. The research leading to these results was funded by the European Community's Seventh Framework Program (FP7/2007-2013) under grant agreement No. 226716 and the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) under the VIDI project “Looking Over the Painter's Shoulder” (grant No. 700.10.426). M. Alfeld is the recipient of a Ph.D. fellowship of the Research Foundation-Flanders (FWO). ; Approved Most recent IF: 1.455; 2013 IF: 1.694
  Call Number UA @ admin @ c:irua:108264 Serial 5826
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