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Author (up) Tadić, M.; Arsoski, V.; Čukarić, N.; Peeters, F.M.
Title The optical excitonic Aharonov-Bohm effect in a few nanometer wide type-I nanorings Type A1 Journal article
Year 2010 Publication Acta physica Polonica: A: general physics, solid state physics, applied physics Abbreviated Journal Acta Phys Pol A
Volume 117 Issue 6 Pages 974-977
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The optical excitonic Aharonov-Bohm effect in type-1 three-dimensional (In, Ga)As/GaAs nanorings in theoretically explored. The single-particle states of the electron and the hole are extracted from the effective mass theory in the presence of inhomogeneous strain, and an exact numerical diagonalization approach is used to compute the exciton states and the oscillator strength fx for exciton recombination. We studied both the large lithographically-defined and small self-assembled rings. Only in smaller self-assembled nanorings we found optical excitonic AharonovBohm effect. Those oscillations are established by anticrossings between the optically active exciton states with zero orbital momentum. In lithographically defined rings, whose average radius is 33 nm, fx shows no oscillations, whereas in the smaller self-assembled nanoring with average radius of 11.5 nm oscillations in fx for the ground exciton state are found as function of the magnetic field that is superposed on a linear dependence. These oscillations are smeared out at finite temperature, thus photoluminescence intensity exhibits step-like variation with magnetic field even at temperature as small as 4.2 K.
Address
Corporate Author Thesis
Publisher Place of Publication Warszawa Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0587-4246 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.469 Times cited Open Access
Notes Approved Most recent IF: 0.469; 2010 IF: 0.467
Call Number UA @ lucian @ c:irua:84080 Serial 2474
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Author (up) Tan, H.; Lebedev, O.I.; McLaughlin, A.C.; Van Tendeloo, G.
Title The superstructure and superconductivity of Ru1222 based RuSr2Gd2-x-yYyCexCu2O10-\delta compounds Type A1 Journal article
Year 2010 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 23 Issue 11 Pages 115013-115013,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract For the first time, the local structure and physical properties of Ru1222 based compounds (RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta) and RuSr(2)Gd(1.8-x)Y(0.2)CexCu(2)O(10) (x = 0.90-0.55)) have been investigated and analyzed together on the very same compounds. The Ru1222 superstructure was confirmed by TEM at a local scale and was suggested to have an orthorhombic symmetry with space group Aba2 and lattice parameters a(s) similar or equal to root 2a, b(s) similar or equal to root 2a and c(s) = c. This new Ru1222 superstructure distortion from tetragonal symmetry is proposed to have a positive correlation with the superconductivity variation of these compounds. The more the distortion towards orthorhombic symmetry, the higher the critical superconducting temperature these compounds can achieve. The T(c)(0) of RuSr(2)Gd(1.8-x)Y(0.2)Ce(x)Cu(2)O(10-delta) (x = 0.85-0.55) increases monotonically from 4 to 16 K when x decreases from 0.85 to 0.70, then RuSr(2)Gd(2)Cu(2)O(8) defects emerge and the T(c) decreases with decreasing x. Ru1212 defects are observed to intergrow epitaxially with the Ru1222 structure as lamellas along the c-axis in RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta). Although Ru1212 is a superconductor, the intergrowth severely restrains its superconductivity.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000284308000013 Publication Date 2010-10-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 1 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 2.878; 2010 IF: 2.402
Call Number UA @ lucian @ c:irua:95553 Serial 3385
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Author (up) Terzano, R.; Santoro, A.; Spagnuolo, M.; Vekemans, B.; Medici, L.; Janssens, K.; Göttlicher, J.; Denecke, M.A.; Mangold, S.; Ruggiero, P.
Title Solving mercury (Hg) speciation in soil samples by synchrotron X-ray microspectroscopic techniques Type A1 Journal article
Year 2010 Publication Environmental pollution Abbreviated Journal Environ Pollut
Volume 158 Issue 8 Pages 2702-2709
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg1. Hg chemical forms were identified and quantified by sequential extractions and bulkand micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as m-XRF, m-XRD and m-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 mm. The main Hg-species found in the soil samples were metacinnabar (b-HgS), cinnabar (a-HgS), corderoite (Hg3S2Cl2), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 mm. No interaction among Hg-species and soil components was observed. All the observed Hgspecies originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280571500026 Publication Date 2010-06-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0269-7491 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.099 Times cited 30 Open Access
Notes ; This research was partially financed by the MIUR (COFIN 2005) project “Innovative chemical, physical, and biological methods to characterize and remediate soils polluted by heavy metals (MICROS)”. Synchrotron experiments at HASYLAB 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). This research was also performed as part of the “Interuniversity Attraction Poles” (IAP6) Program financed by the Belgian government. We thank Gerald Falkenberg and Karen Rickers-Appel for their scientific and technical support in obtaining the experimental data at Beam line L (HASYLAB, DESY, Hamburg, Germany). ; Approved Most recent IF: 5.099; 2010 IF: 3.395
Call Number UA @ admin @ c:irua:84050 Serial 5835
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Author (up) Tikhomirov, V.K.; Rodriguez, V.D.; Kutznetsov, D.; Kirilenko, D.; Van Tendeloo, G.; Moshchalkov, V.V.
Title Preparation and luminescence of bulk oxyfluoride glasses doped with Ag nanoclusters Type A1 Journal article
Year 2010 Publication Optics express Abbreviated Journal Opt Express
Volume 18 Issue 21 Pages 22032-22040
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Bulk oxyfluoride glasses doped with Ag nanoclusters have been prepared using the melt quenching technique. When pumped in the absorption band of Ag nanoclusters between 300 to 500 nm, these glasses emit a very broad luminescence band covering all the visible range with a weak tail extending into the near infrared. The maximum of the luminescence band and its color shifts to the blue with a shortening of the excitation wavelength and an increasing ratio of oxide to fluoride components, resulting in white color luminescence at a particular ratio of oxide to fluoride; with a quantum yield above 20%.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000283686500057 Publication Date 2010-10-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1094-4087; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.307 Times cited 74 Open Access
Notes Methusalem Approved Most recent IF: 3.307; 2010 IF: 3.753
Call Number UA @ lucian @ c:irua:85802 Serial 2698
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Author (up) Tirry, W.; Coghe, F.; Bouvier, S.; Gasperini, M.; Rabet, L.; Schryvers, D.
Title A multi-scale characterization of deformation twins in Ti6Al4V sheet material deformed by simple shear Type A1 Journal article
Year 2010 Publication Materials science and engineering: part A: structural materials: properties, microstructure and processing Abbreviated Journal Mat Sci Eng A-Struct
Volume 527 Issue 16/17 Pages 4136-4145
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ti6Al4V sheet material is subjected to simple shear deformation with strain ratio's of 10%, 30% and 50%. Optical microscopy, transmission electron microscopy and electron backscatter diffraction techniques are applied to study the presence and morphology of deformation twins. Only the View the MathML source type of twins seems to be present with a volume fraction below 1%. These View the MathML source twins show a high density of basal stacking faults of the ABABACAC type identified using atomic resolution transmission electron microscopy. A resolved shear stress analysis shows that twins most often occur on those planes with the highest resolved shear stresses, but that the starting texture is not beneficial for the occurrence of twins. It is further suggested that a transitory strain hardening regime observed around 530 MPa might be related with the onset of twinning.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000278766800068 Publication Date 2010-03-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-5093; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.094 Times cited 20 Open Access
Notes Iap Approved Most recent IF: 3.094; 2010 IF: 2.101
Call Number UA @ lucian @ c:irua:82291 Serial 2212
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Author (up) Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A.
Title Ab initio based atomic scattering amplitudes and {002} electron structure factors of InxGa1-xAs/GaAs quantum wells Type A1 Journal article
Year 2010 Publication Journal of physics : conference series Abbreviated Journal
Volume 209 Issue 1 Pages 012040,1-012040,6
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The atomic scattering amplitudes of the various atoms of the systems Ga1−xInxAs, GaAs1−xNx and InAs1−xNx are calculated using the density functional theory (DFT) approach. The scattering amplitudes of N, Ga, As and In in the model systems are compared with the frequently used Doyle and Turner values. Deviation from the latter values is found for small scattering vectors (s<0.3Å−1) and for these scattering vectors dependence on the orientation of the scattering vector and the chemical environment is reported. We suggest a parametrization of these modified scattering amplitudes (MASAs) for small scattering vectors (s<1.0Å−1). The MASAs are exploited within zero pressure classical Metropolis Monte Carlo (MC), finite temperature calculations to investigate the effect of quantum well size on the electron {002} structure factor (SF) of Ga1−xInxAs quantum wells.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000283739100040 Publication Date 2010-02-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6596; ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:85760 Serial 28
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Author (up) Tkachenko, D.V.; Misko, V.R.; Peeters, F.M.
Title Effect of correlated noise on quasi-one-dimensional diffusion Type A1 Journal article
Year 2010 Publication Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics Abbreviated Journal Phys Rev E
Volume 82 Issue 5 Pages 051102-051102,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Single-file diffusion (SFD) of an infinite one-dimensional chain of interacting particles has a long-time mean-square displacement ∝t1/2, independent of the type of interparticle repulsive interaction. This behavior is also observed in finite-size chains, although only for certain intervals of time t depending on the chain length L, followed by the ∝t for t→∞, as we demonstrate for a closed circular chain of diffusing interacting particles. Here, we show that spatial correlation of noise slows down SFD and can result, depending on the amount of correlated noise, in either subdiffusive behavior ∝tα, where 0<α<1/2, or even in a total suppression of diffusion (in the limit N→∞). Spatial correlation can explain the subdiffusive behavior in recent SFD experiments in circular channels.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000283710100001 Publication Date 2010-11-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 11 Open Access
Notes ; We acknowledge discussions with M. Saint-Jean. This work was supported by the “Odysseus” program of the Flemish Government and the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 2.366; 2010 IF: 2.352
Call Number UA @ lucian @ c:irua:85799 Serial 806
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Author (up) Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H.
Title Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7 Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 5 Pages 054107,1-054107,12
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000280849400001 Publication Date 2010-08-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 13 Open Access
Notes Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83991 Serial 1706
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Author (up) Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Shpanchenko, R.V.; Geibel, C.; Rosner, H.
Title Frustrated square lattice with spatial anisotropy: crystal structure and magnetic properties of PbZnVO(PO4)2 Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 17 Pages 174424,1-174424,13
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Crystal structure and magnetic properties of the layered vanadium phosphate PbZnVO(PO4)2 are studied using x-ray powder diffraction, magnetization and specific-heat measurements, as well as band-structure calculations. The compound resembles AA′VO(PO4)2 vanadium phosphates and fits to the extended frustrated square-lattice model with the couplings J1, J1′ between nearest neighbors and J2, J2′ between next-nearest neighbors. The temperature dependence of the magnetization yields estimates of averaged nearest-neighbor and next-nearest-neighbor couplings, J̅ 1≃−5.2 K and J̅ 2≃10.0 K, respectively. The effective frustration ratio α=J̅ 2/J̅ 1 amounts to −1.9 and suggests columnar antiferromagnetic ordering in PbZnVO(PO4)2. Specific-heat data support the estimates of J̅ 1 and J̅ 2 and indicate a likely magnetic ordering transition at 3.9 K. However, the averaged couplings underestimate the saturation field, thus pointing to the spatial anisotropy of the nearest-neighbor interactions. Band-structure calculations confirm the identification of ferromagnetic J1, J1′ and antiferromagnetic J2, J2′ in PbZnVO(PO4)2 and yield (J1′−J1)≃1.1 K in excellent agreement with the experimental value of 1.1 K, deduced from the difference between the expected and experimentally measured saturation fields. Based on the comparison of layered vanadium phosphates with different metal cations, we show that a moderate spatial anisotropy of the frustrated square lattice has minor influence on the thermodynamic properties of the model. We discuss relevant geometrical parameters, controlling the exchange interactions in these compounds and propose a strategy for further design of strongly frustrated square-lattice materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000278141600082 Publication Date 2010-05-25
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 27 Open Access
Notes Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:83384 Serial 1294
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Author (up) Tsvyashchenko, A.V.; Nikolaev, A.V.; Velichkov, A.I.; Salamatin, A.V.; Fomicheva, L.N.; Ryasny, G.K.; Sorokin, A.A.; Kochetov, O.I.; Budzynski, M.; Michel, K.H.
Title Lowering of the spatial symmetry at the gamma ->alpha phase transition in cerium Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 9 Pages 1-4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using time-differential perturbed angular correlation spectroscopy we have measured the electric field gradient (EFG) at 111Cd probe nuclei in solid Ce in a pressure range up to 8 GPa. Covering various allotropic phases of Ce, we find that the value of the EFG in the cubic α phase is almost four times larger than in the cubic γ phase and close to values in the noncubic phases α′ and α″. These results together with the differences in time modulation of the spectra are interpreted as evidence for quadrupolar electronic charge-density ordering and symmetry lowering at the γ→α transition while the lattice remains face-centered cubic
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000282004400001 Publication Date 2010-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 11 Open Access
Notes ; This work is supported by the Program of the Presidium of the Russian Academy of Sciences “Physics of Strongly Compressed Matter.” We are grateful to S. M. Stishov, B. Verberck, A. N. Grum-Grzhimailo, V. B. Brudanin and G. Heger for support of this work and discussion of the results. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:85464 Serial 1854
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Author (up) Turner, S.; Tavernier, S.M.F.; Huyberechts, G.; Bals, S.; Batenburg, K.J.; Van Tendeloo, G.
Title Assisted spray pyrolysis production and characterisation of ZnO nanoparticles with narrow size distribution Type A1 Journal article
Year 2010 Publication Journal of nanoparticle research Abbreviated Journal J Nanopart Res
Volume 12 Issue 2 Pages 615-622
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Nano-sized ZnO particles with a narrow size distribution and high crystallinity were prepared from aqueous solutions with high concentrations of Zn2+ containing salts and citric acid in a conventional spray pyrolysis setup. Structure, morphology and size of the produced material were compared to ZnO material produced by simple spray pyrolysis of zinc nitrates in the same experimental setup. Using transmission electron microscopy and electron tomography it has been shown that citric acid-assisted spray pyrolysed material is made up of micron sized secondary particles comprising a shell of lightly agglomerated, monocrystalline primary ZnO nanoparticles with sizes in the 2030 nm range, separable by a simple ultrasonic treatment step.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos 000275318700025 Publication Date 2009-04-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1388-0764;1572-896X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.02 Times cited 27 Open Access
Notes Esteem 026019 Approved Most recent IF: 2.02; 2010 IF: 3.253
Call Number UA @ lucian @ c:irua:81771 Serial 156
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Author (up) Ustarroz, J.; Gupta, U.; Hubin, A.; Bals, S.; Terryn, H.
Title Electrodeposition of Ag nanoparticles onto carbon coated TEM grids : a direct approach to study early stages of nucleation Type A1 Journal article
Year 2010 Publication Electrochemistry communications Abbreviated Journal Electrochem Commun
Volume 12 Issue 12 Pages 1706-1709
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An innovative experimental approach to study the electrodeposition of small nanoparticles and the early stages of electrochemical nucleation and growth is presented. Carbon coated gold TEM grids are used as substrates for the electrodeposition of silver nanoparticles so that electrochemical data, FESEM, HAADFSTEM and HRTEM data can be acquired from the same sample without the need to remove the particles from the substrate. It is shown that the real distribution of nanoparticles cannot be resolved by FESEM whereas HAADFSTEM analysis confirms that a distribution of small nanoparticles (d ≈ 12 nm) coexist with large nanoparticles corresponding to a bimodal size distribution. Besides, particles grown under the same conditions have been found to present different structures such as monocrystals, polycrystals or aggregates of smaller particles.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000285904700010 Publication Date 2010-10-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1388-2481; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.396 Times cited 52 Open Access
Notes Fwo Approved Most recent IF: 4.396; 2010 IF: 4.287
Call Number UA @ lucian @ c:irua:87612 Serial 900
Permanent link to this record
 
 
Author (up) Van Aert, S.; Chen, J.H.; van Dyck, D.
Title Linear versus non-linear structural information limit in high-resolution transmission electron microscopy Type A1 Journal article
Year 2010 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 110 Issue 11 Pages 1404-1410
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract A widely used performance criterion in high-resolution transmission electron microscopy (HRTEM) is the information limit. It corresponds to the inverse of the maximum spatial object frequency that is linearly transmitted with sufficient intensity from the exit plane of the object to the image plane and is limited due to partial temporal coherence. In practice, the information limit is often measured from a diffractogram or from Young's fringes assuming a weak phase object scattering beyond the inverse of the information limit. However, for an aberration corrected electron microscope, with an information limit in the sub-angstrom range, weak phase objects are no longer applicable since they do not scatter sufficiently in this range. Therefore, one relies on more strongly scattering objects such as crystals of heavy atoms observed along a low index zone axis. In that case, dynamical scattering becomes important such that the non-linear and linear interaction may be equally important. The non-linear interaction may then set the experimental cut-off frequency observed in a diffractogram. The goal of this paper is to quantify both the linear and the non-linear information transfer in terms of closed form analytical expressions. Whereas the cut-off frequency set by the linear transfer can be directly related with the attainable resolution, information from the non-linear transfer can only be extracted using quantitative, model-based methods. In contrast to the historic definition of the information limit depending on microscope parameters only, the expressions derived in this paper explicitly incorporate their dependence on the structure parameters as well. In order to emphasize this dependence and to distinguish from the usual information limit, the expressions derived for the inverse cut-off frequencies will be referred to as the linear and non-linear structural information limit. The present findings confirm the well-known result that partial temporal coherence has different effects on the transfer of the linear and non-linear terms, such that the non-linear imaging contributions are damped less than the linear imaging contributions at high spatial frequencies. This will be important when coherent aberrations such as spherical aberration and defocus are reduced.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000282562100008 Publication Date 2010-07-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 6 Open Access
Notes Fwo Approved Most recent IF: 2.843; 2010 IF: 2.063
Call Number UA @ lucian @ c:irua:83689 Serial 1821
Permanent link to this record
 
 
Author (up) Van de Vyver, S.; Geboers, J.; Dusselier, M.; Schepers, H.; Vosch, T.; Zhang, L.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F.
Title Selective bifunctional catalytic conversion of cellulose over reshaped ni particles at the tip of carbon nanofibers Type A1 Journal article
Year 2010 Publication Chemsuschem Abbreviated Journal Chemsuschem
Volume 3 Issue 6 Pages 698-701
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000279753300011 Publication Date 2010-05-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1864-5631;1864-564X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.226 Times cited 136 Open Access
Notes Approved Most recent IF: 7.226; 2010 IF: 6.325
Call Number UA @ lucian @ c:irua:95657 Serial 2962
Permanent link to this record
 
 
Author (up) van den Broek, W.; Van Aert, S.; van Dyck, D.
Title A model based reconstruction technique for depth sectioning with scanning transmission electron microscopy Type A1 Journal article
Year 2010 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 110 Issue 5 Pages 548-554
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Depth sectioning in high angular annular dark field scanning transmission electron microscopy is considered a candidate for three-dimensional characterization on the atomic scale. However at present the depth resolution is still far from the atomic level, due to strong limitations in the opening angle of the beam. In this paper we introduce a new, parameter based tomographic reconstruction algorithm that allows to make maximal use of the prior knowledge about the constituent atom types and the microscope settings, so as to retrieve the atomic positions and push the resolution to the atomic level in all three dimensions.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000279065700022 Publication Date 2009-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 16 Open Access
Notes Fwo Approved Most recent IF: 2.843; 2010 IF: 2.063
Call Number UA @ lucian @ c:irua:83690 Serial 2104
Permanent link to this record
 
 
Author (up) van den Heuvel, W.; Tikhomirov, V.K.; Kirilenko, D.; Schildermans, N.; Chibotaru, L.F.; Vanacken, J.; Gredin, P.; Mortier, M.; Van Tendeloo, G.; Moshchalkov, V.V.
Title Ultralow blocking temperature and breakdown of the giant spin model in Er3+-doped nanoparticles Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 9 Pages 094421-094421,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The magnetization of luminescent Er3+-doped PbF2 nanoparticles (formula Er0.3Pb0.7F2.3) has been studied. Despite the high concentration of the doping Er3+ ions and relatively large size (8 nm) of these nanoparticles we have found no deviation between field-cooled and zero-field-cooled magnetization curves down to T=0.35 K, which points out an ultralow blocking temperature for the reversal of magnetization. We also have found strongly deviating magnetization curves M(H/T) for different temperatures T. These results altogether show that the investigated nanoparticles are not superparamagnetic, but rather each Er3+ ion in these nanoparticles is found in a paramagnetic state down to very low temperatures, which implies the breakdown of the Néel-Brown giant spin model in the case of these nanoparticles. Calculations of magnetization within a paramagnetic model of noninteracting Er3+ ions completely support this conclusion. Due to the ultralow blocking temperature, these nanoparticles have a potential for magnetic field-induced nanoscale refrigeration with an option of their optical localization and temperature control.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281773300005 Publication Date 2010-09-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 11 Open Access
Notes Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:85423 Serial 3796
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Author (up) van der Linden, V.; Schalm, O.; Houbraken, J.; Thomas, M.; Meesdom, E.; Devos, A.; van Dooren, R.; Nieuwdorp, H.; Janssen, E.; Janssens, K.
Title Chemical analysis of 16th to 19th century Limoges School painted enamel objects in three museums of the Low Countries Type A1 Journal article
Year 2010 Publication X-ray spectrometry Abbreviated Journal X-Ray Spectrom
Volume 39 Issue 2 Pages 112-121
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this study, the results of analysing of a series of 16th-19th century painted enamel objects of the Limoges School currently in collections in three Dutch and Flemish museums by means of portable and micro x-ray fluorescence analysis (PXRF and µ-XRF) and electron probe micro analysis (EPMA) are presented. The aim of the investigation was the authentication of specific pieces. Therefore, the glass compositions as well as the (glass) colouring agents used by the Limoges' artists were studied as a function of the age of the objects. Due to the evolution of these properties, it is possible to approximately date these objects based on their chemical composition. The complete émail peint collection of the Museum Boijmans-Van Beuningen (Rotterdam, The Netherlands), consisting of 20 émail peint plaques, was analysed with µ-XRF. Quantitative information was obtained by EPMA analysis of 15 enamel fragments of objects from museum and private collections in the Low Countries. PXRF analyses were performed on the painted enamel collection of the Antwerp Vleeshuis Museum (13 objects) and the Mayer van den Bergh Museum (4 objects) and on a set of 18 plaques that were donated to the Boijmans-Van Beuningen Museum by a private collector. The results obtained by means of EPMA, µ-XRF and PXRF proved to be useful in the discrimination of 16th century painted enamel objects from those of the19th century. From a total of 70 objects examined, 2 objects (OM964A and OM993) featured a chemical signature that deviated from the published literature composition and pigment use consistent with its presumed period of manufacture.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000275959400007 Publication Date 2009-08-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0049-8246 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.298 Times cited 8 Open Access
Notes ; ; Approved Most recent IF: 1.298; 2010 IF: 1.661
Call Number UA @ admin @ c:irua:82325 Serial 5509
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Author (up) van der Linden, V.; Van de Casteele, E.; Thomas, M.S.; de Vos, A.; Janssen, E.; Janssens, K.
Title Analysis of micro computed tomography images; a look inside historic enamelled metal objects Type A1 Journal article
Year 2010 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
Volume 98 Issue 2 Pages 385-392
Keywords A1 Journal article; Vision lab; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this study the usefulness of micro-Computed Tomography (µ-CT) for the in-depth analysis of enamelled metal objects was tested. Usually investigations of enamelled metal artefacts are restricted to non-destructive surface analysis or analysis of cross sections after destructive sampling. Radiography, a commonly used technique in the field of cultural heritage studies, is limited to providing two-dimensional information about a three-dimensional object (Lang and Middleton, Radiography of Cultural Material, pp. 6061, Elsevier-Butterworth-Heinemann, Amsterdam-Stoneham-London, 2005). Obtaining virtual slices and information about the internal structure of these objects was made possible by CT analysis. With this technique the underlying metal work was studied without removing the decorative enamel layer. Moreover visible defects such as cracks were measured in both width and depth and as of yet invisible defects and weaker areas are visualised. All these features are of great interest to restorers and conservators as they allow a view inside these objects without so much as touching them.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000272158200018 Publication Date 2009-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.455 Times cited 3 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “Atom” (Research Fund University of Antwerp, Belgium), FWO (Brussels, Belgium) projects nos. G.0177.03, G.0103.04 and G.0689.06. ; Approved Most recent IF: 1.455; 2010 IF: 1.765
Call Number UA @ admin @ c:irua:80421 Serial 5469
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Author (up) van der Snickt, G.; Janssens, K.; Schalm, O.; Aibéo, C.; Kloust, H.; Alfeld, M.
Title James Ensor's pigment use: artistic and material evolution studied by means of portable X-ray fluorescence spectrometry Type A1 Journal article
Year 2010 Publication X-ray spectrometry Abbreviated Journal X-Ray Spectrom
Volume 39 Issue 2 Pages 103-111
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this paper, portable X-ray fluorescence spectrometry (PXRF) was employed as a screening tool for determining and comparing the pigment use in a large series of paintings by the Belgian artist James Ensor (1860-1949). Benefits and drawbacks of PXRF as a method, and the instrument employed, are discussed from a practical, conservation and instrumental perspective. Regardless of several restrictions due to the set-up and/or the analytical method, it appeared feasible to document the evolution with time in Ensor's use of inorganic pigments and to correlate this technical evolution with stylistic developments, Nevertheless, it became clear that a full identification of all materials present can only be done by means of the analysis of (cross-sectioned) samples.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000275959400006 Publication Date 2009-12-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0049-8246 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.298 Times cited 25 Open Access
Notes ; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The staff of the different museums and private institutions is acknowledged for rendering their assistance to this research, i.e. by making all paintings available for analysis and authorising the publication of the images in this article. Therefore, a word of gratitude to Paul Huvenne, Yolande Deckers, Herwig Todts, Stef Antonissen, Gwen Borms and Lizet Klaassen of the Koninklijk Museum voor Schone Kunsten Antwerpen (KMSKA), Luuk Van der Loeff of the Kroller-Muller Museum in Otterlo and Mireille Engel, Barbara De Jong of the Musea aan Zee (MuZee), Patricia Jaspers of the Dexia bank, Hildegard Van de Velde of the KBC bank and Frederik Leen of the Koninklijke Musea voor Schone Kunsten van Belgie (KMSKB). Special thanks to Xavier Tricot and the other members of the Ensor committee for their valuable feedback. ; Approved Most recent IF: 1.298; 2010 IF: 1.661
Call Number UA @ admin @ c:irua:82324 Serial 5680
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Author (up) van Meel, K.; Horemans, B.; Krata, A.; Bencs, L.; Buczyńska, A.J.; Dirtu, A.C.; Worobiec, A.; Van Grieken, R.
Title Elemental concentrations in aerosols at the Belgian coast versus seasons and air mass trajectories Type A1 Journal article
Year 2010 Publication Environmental chemistry letters Abbreviated Journal
Volume 8 Issue 2 Pages 157-163
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP); Toxicological Centre
Abstract Marine aerosols have extensively been monitored in the framework of a research project to investigate the inorganic and organic nutrient fluxes of the atmospheric nitrogen input into the North Sea. As a part of this project bulk analysis was also performed by energy dispersive X-ray fluorescence (EDXRF) on a total of 366 samples in order to provide detailed elemental composition. Samples have been clustered per campaign and differences were related to backward trajectories. Elements as Cl, Si, and S appeared to be the best tracers for coastal aerosols. Therefore they have been chosen to represent each campaign and to map the seasonal variations. It is clear that Cl is an excellent tracer for oceanic trajectories, while a less clear correlation between the soil dust components and the air mass trajectories is found.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000277786900007 Publication Date 2009-02-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1610-3653 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:82494 Serial 7893
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Author (up) Van Meensel, J.; Lauwers, L.; Van Huylenbroeck, G.; Van Passel, S.
Title Comparing frontier methods for economic-environmental trade-off analysis Type A1 Journal article
Year 2010 Publication European Journal Of Operational Research Abbreviated Journal Eur J Oper Res
Volume 207 Issue 2 Pages 1027-1040
Keywords A1 Journal article; Economics
Abstract This paper uses a mechanistic frontier approach as a reference to evaluate the ability of conventional parametric (SFA) and non-parametric (DEA) frontier approaches for analyzing economicenvironmental trade-offs. Conventional frontier approaches are environmentally adjusted through incorporating the materials balance principle. The analysis is worked out for the Flemish pig finishing case, which is both representative and didactic. Results show that, on average, SFA and DEA yield adequate economicenvironmental trade-offs. Both methods are good estimators for technical efficiency. Cost allocative and environmental allocative efficiency scores are less robust, due to the well-known methodological advantages and disadvantages of SFA and DEA. For particular firms, SFA, DEA and the mechanistic approach may yield different economicenvironmental trade-offs. One has therefore to be careful when using conventional frontier approaches for firm-specific decision support. The mechanistic approach allows for optimizing performances per average present finisher, which is the production unit in pig finishing. Conventional frontier methods do not allow for this optimization since the number of average present finishers varies along the production functions. Since the mechanistic production function is based on underlying growth, feed uptake and mortality functions, additional firm-specific indicators can also be calculated at each point of the production function.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281107200045 Publication Date 2010-05-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0377-2217 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.297 Times cited 18 Open Access
Notes ; This research is funded by the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT Vlaanderen). ; Approved Most recent IF: 3.297; 2010 IF: 2.159
Call Number UA @ admin @ c:irua:136761 Serial 6171
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Author (up) Vandenberghe, W.; Sorée, B.; Magnus, W.; Groeseneken, G.
Title Zener tunneling in semiconductors under nonuniform electric fields Type A1 Journal article
Year 2010 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 107 Issue 5 Pages 054520,1-054520,7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Recently, a renewed interest in Zener tunneling has arisen because of its increasing impact on semiconductor device performance at nanometer dimensions. In this paper we evaluate the tunnel probability under the action of a nonuniform electric field using a two-band model and arrive at significant deviations from the commonly used Kanes model, valid for weak uniform fields only. A threshold on the junction bias where Kanes model for Zener tunneling breaks down is determined. Comparison with Kanes model particularly shows that our calculation yields a higher tunnel probability for intermediate electric fields and a lower tunnel probability for high electric fields. When performing a current calculation comparing to the WKB approximation for the case of an abrupt p-n junction significant differences concerning the shape of the I-V curve are demonstrated.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000275657500136 Publication Date 2010-03-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 22 Open Access
Notes ; William Vandenberghe gratefully acknowledges the support of a Ph. D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). These authors acknowledge the support from IMEC's Industrial Affiliation Program and the authors would like to thank Anne Verhulst for useful comments. ; Approved Most recent IF: 2.068; 2010 IF: 2.079
Call Number UA @ lucian @ c:irua:82450 Serial 3929
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Author (up) Vassiliev, S.Y.; Laurinavichute, V.K.; Abakumov, A.M.; Govorov, V.A.; Bendovskii, E.B.; Turner, S.; Filatov, A.Y.; Tarasovskii, V.P.; Borzenko, A.G.; Alekseeva, A.M.; Antipov, E.V.
Title Microstructural aspects of the degradation behavior of SnO2-based anodes for aluminum electrolysis Type A1 Journal article
Year 2010 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
Volume 157 Issue 5 Pages C178-C186
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The performance of SnO2 ceramic anodes doped with copper and antimony oxides was examined in cryolite alumina melts under anodic polarization at different cryolite ratios, temperatures, times, and current densities. The corroded part consists of a narrow strong corrosion zone at the anode surface with damage of the intergrain contacts and a large increase in porosity, a wider moderate corrosion zone with a smaller porosity increase, and a Cu depletion zone, where the ceramic retains its initial microstructure and a slight porosity increase occurs due to the removal of the Cu-rich inclusions. Mechanical destruction of the anode was never observed in the 10100 h tests. A microstructural model of the ceramic was suggested, consisting of grains with an Sb-doped SnO2 grain core surrounded by an ~200 to 500 nm grain shell where SnO2 was simultaneously doped with Sb and Mn+ (M=Cu2+,Fe3+,Al3+). The grains were separated by a few nanometers thick Cu-enriched grain boundaries. Different secondary charge carrier (holes) concentrations and electric conductivities in the grain core and grain shell result in a higher current density at the intergrain regions that leads to their profound degradation, especially in the low temperature acidic melt.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000276555300037 Publication Date 2010-04-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4651; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.259 Times cited 3 Open Access
Notes Approved Most recent IF: 3.259; 2010 IF: 2.427
Call Number UA @ lucian @ c:irua:82260 Serial 2040
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Author (up) Vazquez, C.; Martin Palacios, O.; Darchuk, L.; Marco Parra, L.-M.
Title Compositional study of prehistoric pigments (Carriqueo rock shelter, Argentina) by synchrotron radiation X-ray diffraction Type A1 Journal article
Year 2010 Publication Powder diffraction Abbreviated Journal
Volume 25 Issue 3 Pages 264-269
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this work synchrotron radiation X-ray diffraction technique was successfully applied for the analysis of pigments found in excavation at Carriqueo rock shelter, Neuquen, Argentina. The pigment samples of orange, red, and brown shades were collected from different levels of this archaeological site and compared with a suspected source of provenance (La Oficina creek). X-ray diffraction patterns of several yellowish, reddish, and red pigments showed the presence of haematite, goethite, kaolinite, and quartz. The majority of Carriqueo collected samples belonged to the same group of the suspected source, having haematite and quartz as main crystalline phases. The results indicate that the raw material from La Oficina is the source of most of the pigments found at Carriqueo. The present work helps us to understand the strategy of supplying raw materials by human groups in the North Patagonia region. (C) 2010 International Centre for Diffraction Data. [DOI: 10.1154/1.3478884]
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000282386500009 Publication Date 2010-09-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0885-7156 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:95582 Serial 7717
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Author (up) Verbeeck, J.; Bals, S.; Lamoen, D.; Luysberg, M.; Huijben, M.; Rijnders, G.; Brinkman, A.; Hilgenkamp, H.; Blank, D.H.A.; Van Tendeloo, G.
Title Electronic reconstruction at n-type SrTiO3/LaAlO3 interfaces Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue 8 Pages 085113,1-085113,6
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Electron-energy-loss spectroscopy (EELS) is used to investigate single layers of LaAlO3 grown on SrTiO3 having an n-type interface as well as multilayers of LaAlO3 and SrTiO3 in which both n- and p-type interfaces occur. Only minor changes in Ti valence at the n-type interface are observed. This finding seems to contradict earlier experiments for other SrTiO3/LaAlO3 systems where large deviations in Ti valency were assumed to be responsible for the conductivity of these interfaces. Ab initio calculations have been carried out in order to interpret our EELS results. Using the concept of Bader charges, it is demonstrated that the so-called polar discontinuity is mainly resolved by lattice distortions and to a far lesser extent by changes in valency for both single layer and multilayer geometries.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000275053300040 Publication Date 2010-02-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 25 Open Access
Notes Esteem 026019; Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:81768UA @ admin @ c:irua:81768 Serial 1005
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Author (up) Verbeeck, J.; Tian, H.; Schattschneider, P.
Title Production and application of electron vortex beams Type A1 Journal article
Year 2010 Publication Nature Abbreviated Journal Nature
Volume 467 Issue 7313 Pages 301-304
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Vortex beams (also known as beams with a phase singularity) consist of spiralling wavefronts that give rise to angular momentum around the propagation direction. Vortex photon beams are widely used in applications such as optical tweezers to manipulate micrometre-sized particles and in micro-motors to provide angular momentum1, 2, improving channel capacity in optical3 and radio-wave4 information transfer, astrophysics5 and so on6. Very recently, an experimental realization of vortex beams formed of electrons was demonstrated7. Here we describe the creation of vortex electron beams, making use of a versatile holographic reconstruction technique in a transmission electron microscope. This technique is a reproducible method of creating vortex electron beams in a conventional electron microscope. We demonstrate how they may be used in electron energy-loss spectroscopy to detect the magnetic state of materials and describe their properties. Our results show that electron vortex beams hold promise for new applications, in particular for analysing and manipulating nanomaterials, and can be easily produced.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000281824900033 Publication Date 2010-09-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-0836;1476-4687; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 40.137 Times cited 626 Open Access
Notes Esteem 026019; Fwo Approved Most recent IF: 40.137; 2010 IF: 36.104
Call Number UA @ lucian @ c:irua:84878UA @ admin @ c:irua:84878 Serial 2720
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Author (up) Verbeeck, J.; Van Aert, S.; Zhang, L.; Haiyan, T.; Schattschneider, P.; Rosenauer, A.
Title Computational aspects in quantitative EELS Type A1 Journal article
Year 2010 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
Volume 16 Issue S:2 Pages 240-241
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge, Mass. Editor
Language Wos Publication Date 2010-08-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record
Impact Factor 1.891 Times cited Open Access
Notes Approved Most recent IF: 1.891; 2010 IF: 3.259
Call Number UA @ lucian @ c:irua:96556UA @ admin @ c:irua:96556 Serial 454
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Author (up) Verhulst, A.; Sorée, B.; Leonelli, D.; Vandenberghe, W.G.; Groeseneken, G.
Title Modeling the single-gate, double-gate, and gate-all-around tunnel field-effect transistor Type A1 Journal article
Year 2010 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 107 Issue 2 Pages 024518,1-024518,8
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract Tunnel field-effect transistors (TFETs) are potential successors of metal-oxide-semiconductor FETs because scaling the supply voltage below 1 V is possible due to the absence of a subthreshold-swing limit of 60 mV/decade. The modeling of the TFET performance, however, is still preliminary. We have developed models allowing a direct comparison between the single-gate, double-gate, and gate-all-around configuration at high drain voltage, when the drain-voltage dependence is negligible, and we provide improved insight in the TFET physics. The dependence of the tunnel current on device parameters is analyzed, in particular, the scaling with gate-dielectric thickness, channel thickness, and dielectric constants of gate dielectric and channel material. We show that scaling the gate-dielectric thickness improves the TFET performance more than scaling the channel thickness and that improvements are often overestimated. There is qualitative agreement between our model and our experimental data.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000274180600122 Publication Date 2010-01-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 150 Open Access
Notes Approved Most recent IF: 2.068; 2010 IF: 2.079
Call Number UA @ lucian @ c:irua:89507 Serial 2146
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Author (up) Verleysen, E.; Bender, H.; Richard, O.; Schryvers, D.; Vandervorst, W.
Title Characterization of nickel silicides using EELS-based methods Type A1 Journal article
Year 2010 Publication Journal of microscopy Abbreviated Journal J Microsc-Oxford
Volume 240 Issue 1 Pages 75-82
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The characterization of Ni-silicides using electron energy loss spectroscopy (EELS) based methods is discussed. A series of Ni-silicide phases is examined: Ni3Si, Ni31Si12, Ni2Si, NiSi and NiSi2. The composition of these phases is determined by quantitative core-loss EELS. A study of the low loss part of the EELS spectrum shows that both the energy and the shape of the plasmon peak are characteristic for each phase. Examination of the Ni-L edge energy loss near edge structure (ELNES) shows that the ratio and the sum of the L2 and L3 white line intensities are also characteristic for each phase. The sum of the white line intensities is used to determine the trend in electron occupation of the 3d states of the phases. The dependence of the plasmon energy on the electron occupation of the 3d states is demonstrated.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000281715400009 Publication Date 2010-05-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2720; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.692 Times cited 11 Open Access
Notes Approved Most recent IF: 1.692; 2010 IF: 1.872
Call Number UA @ lucian @ c:irua:84879 Serial 329
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Author (up) Verlooy, P.L.H.; Robeyns, K.; van Meervelt, L.; Lebedev, O.I.; Van Tendeloo, G.; Martens, J.A.; Kirschhock, C.E.A.
Title Synthesis and characterization of the new cyclosilicate hydrate (hexamethyleneimine)4.[Si8O16(OH)4].12H2O Type A1 Journal article
Year 2010 Publication Microporous and mesoporous materials: zeolites, clays, carbons and related materials Abbreviated Journal Micropor Mesopor Mat
Volume 130 Issue 1/3 Pages 14-20
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new cyclosilicate hydrate with composition (C6H14N)4·[Si8O16(OH)4]·12H2O was crystallized and the structure determined by single-crystal X-ray diffraction. The structure, described by the tetragonal space group I41/a, with unit cell dimensions of a = 39.2150(2) Å and c = 14.1553(2) Å, contains columns of hydrogen-bonded cubic octamer silicate anions. The space between silicate columns holds hydrogen-bonded water and protonated hexamethyleneimine molecules compensating the negative charge of the silicate. The crystal water can be removed resulting in a rearrangement of the columns into orthorhombic symmetry. Removal of the organic moiety causes amorphisation. Flash evacuation results in a new microporous material with pore volumes typical of a zeolite.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000275702600003 Publication Date 2009-10-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1387-1811; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.615 Times cited 5 Open Access
Notes Approved Most recent IF: 3.615; 2010 IF: 3.220
Call Number UA @ lucian @ c:irua:82448 Serial 3418
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