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Author Schattschneider, P.; Verbeeck, J.; Hamon, A.L.
Title Real space maps of atomic transitions Type A1 Journal article
Year 2009 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 109 Issue 7 Pages 781-787
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Considering the rapid technical development of transmission electron microscopes, we investigate the possibility to map electronic transitions in real space on the atomic scale. To this purpose, we analyse the information carried by the scatterer's initial and final state wave functions and the role of the different atomic transition channels for the inelastic scattering cross section. It is shown that the change in the magnetic quantum number in the transition can be mapped. Two experimental set-ups are proposed, one blocking half the diffraction plane, the other one using a cylinder lens for imaging. Both methods break the conventional circular symmetry in the electron microscope making it possible to detect the handedness of electronic transitions as an asymmetry in the image intensity. This finding is of important for atomic resolution energy-loss magnetic chiral dichroism (EMCD), allowing to obtain the magnetic moments of single atoms.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000266787900002 Publication Date (up) 2009-03-01
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 10 Open Access
Notes J.V. acknowledges the FWO-Vlaanderen for support (contract no. G.0147.06) and the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. Approved Most recent IF: 2.843; 2009 IF: 2.067
Call Number UA @ lucian @ c:irua:77360UA @ admin @ c:irua:77360 Serial 2829
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Author Georgieva, V.; Saraiva, M.; Jehanathan, N.; Lebelev, O.I.; Depla, D.; Bogaerts, A.
Title Sputter-deposited Mg-Al-O thin films: linking molecular dynamics simulations to experiments Type A1 Journal article
Year 2009 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 42 Issue 6 Pages 065107,1-065107,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Using a molecular dynamics model the crystallinity of MgxAlyOz thin films with a variation in the stoichiometry of the thin film is studied at operating conditions similar to the experimental operating conditions of a dual magnetron sputter deposition system. The films are deposited on a crystalline or amorphous substrate. The Mg metal content in the film ranged from 100% (i.e. MgO film) to 0% (i.e. Al2O3 film). The radial distribution function and density of the films are calculated. The results are compared with x-ray diffraction and transmission electron microscopy analyses of experimentally deposited thin films by the dual magnetron reactive sputtering process. Both simulation and experimental results show that the structure of the MgAlO film varies from crystalline to amorphous when the Mg concentration decreases. It seems that the crystalline MgAlO films have a MgO structure with Al atoms in between.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000263824200024 Publication Date (up) 2009-03-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 37 Open Access
Notes Iwt Approved Most recent IF: 2.588; 2009 IF: 2.083
Call Number UA @ lucian @ c:irua:73246 Serial 3110
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Author Bittencourt, C.; van Lier, G.; Ke, X.; Suarez-Martinez, I.; Felten, A.; Ghijsen, J.; Van Tendeloo, G.; Ewels, C.O.
Title Spectroscopy and defect identification for fluorinated carbon nanotubes Type A1 Journal article
Year 2009 Publication ChemPhysChem : a European journal of chemical physics and physical chemistry Abbreviated Journal Chemphyschem
Volume 10 Issue 6 Pages 920-925
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Multi-wall carbon nanotubes (MWCNTs) were exposed to a CF4 radio-frequency (rf) plasma. High-resolution photoelectron spectroscopy shows that the treatment effectively grafts fluorine atoms onto the MWCNTs, altering the valence electronic states. Fluorine surface concentration can be tuned by varying the exposure time. Evaporation of gold onto MWCNTs is used to mark active site formation. High-resolution transmission electron microscopy coupled with density functional theory (DFT) modelling is used to characterise the surface defects formed, indicating that the plasma treatment does not etch the tube surface. We suggest that this combination of theory and microscopy of thermally evaporated gold atoms onto the CNT surface may be a powerful approach to characterise both surface defect density as well as defect type.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000265469200011 Publication Date (up) 2009-03-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1439-4235;1439-7641; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.075 Times cited 14 Open Access
Notes Iuap; Fwo Approved Most recent IF: 3.075; 2009 IF: 3.453
Call Number UA @ lucian @ c:irua:77315 Serial 3073
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Author Shpanchenko, R.V.; Tsirlin, A.A.; Hadermann, J.; Antipov, E.V.
Title Synthesis and crystal structure of new titanyl phosphate Sr2TiO(PO4)2 Type A1 Journal article
Year 2008 Publication Russian chemical bulletin Abbreviated Journal Russ Chem B+
Volume 57 Issue 3 Pages 552-556
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract New strontium titanyl phosphate Sr2TiO(PO4)2 (1) was synthesized and characterized by X-ray powder diffraction, electron diffraction, high-resolution electron microscopy, and band structure calculations. Titanyl phosphate 1 is isostructural with vanadyl phosphate Sr2VO(PO4)2 and has a layered structure. The titanium atoms are shifted from the centers of the TiO6 octahedra and form short (1.74 Å) titanyl bonds. The structure of 1 is an unusual example of the disordered orientation of the chains formed by TiO6 octahedra in complex titanium phosphates.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000263566900015 Publication Date (up) 2009-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1066-5285;1573-9171; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.529 Times cited 2 Open Access
Notes Approved Most recent IF: 0.529; 2008 IF: 0.469
Call Number UA @ lucian @ c:irua:73712 Serial 3423
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Author Krata, A.; Kontozova-Deutsch, V.; Bencs, L.; Deutsch, F.; Van Grieken, R.
Title Single-run ion chromatographic separation of inorganic and low-molecular-mass organic anions under isocratic elution: application to environmental samples Type A1 Journal article
Year 2009 Publication Talanta : the international journal of pure and applied analytical chemistry Abbreviated Journal
Volume 79 Issue 1 Pages 16-21
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract For the isocratic ion chromatography (IC) separation of low-molecular-mass organic acids and inorganic anions three different anion-exchange columns were studied: IonPac AS14 (9 ìm particle size), Allsep A-2 (7 ìm particle size), and IC SI-50 4E (5 ìm particle size). A complete baseline separation for all analyzed anions (i.e., F−, acetate, formate, Cl−, NO2−, Br−, NO3−, HPO42− and SO42−) in one analytical cycle of shorter than 17 min was achieved on the IC SI-50 4E column, using an eluent mixture of 3.2 mM Na2CO3 and 1.0 mM NaHCO3 with a flow rate of 1.0 mL min−1. On the IonPac AS14 column, it was possible to separate acetate from inorganic anions in one run (i.e., less than 9 min), but not formate, under the following conditions: 3.5 mM Na2CO3 plus 1.0 mM NaHCO3 with a flow rate of 1.2 mL min−1. Therefore, it was necessary to adapt a second run with a 2.0 mM Na2B4O7 solution as an eluent under a flow rate of 0.8 mL min−1 for the separation of organic ions, which considerably enlarged the analysis time. For the Allsep A-2 column, using an eluent mixture of 1.2 mM Na2CO3 plus 1.5 mM NaHCO3 with a flow rate of 1.6 mL min−1, it was possible to separate almost all anions in one run within 25 min, except the fluoride-acetate critical pair. A Certified Multianion Standard Solution PRIMUS for IC was used for the validation of the analytical methods. The lowest RSDs (less than 1%) and the best LODs (0.02, 0.2, 0.16, 0.11, 0.06, 0.05, 0.04, 0.14 and 0.09 mg L−1 for F−, Ac−, For−, Cl−, NO2−, Br−, NO3−, HPO42− and SO42−, respectively) were achieved using the IC SI-50 4E column. This column was applied for the separation of concerned ions in environmental precipitation samples such as snow, hail and rainwater.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000266187600004 Publication Date (up) 2009-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-9140; 1873-3573 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:75475 Serial 8542
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Author Papp, G.; Peeters, F.M.
Title Magneto-ballistic transport through micro-structured junctions on a curved two-dimensional electron gas Type A1 Journal article
Year 2009 Publication Solid state communications Abbreviated Journal Solid State Commun
Volume 149 Issue 19/20 Pages 778-780
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate theoretically the ballistic transport in a two-dimensional electron gas, which is rolled up as a tube and is micro-structured into a Hall bar. A uniform magnetic field applied to such a curved surface results in a non-uniform perpendicular magnetic field. The bend resistances become asymmetric with respect to the orientation of the magnetic field due to the varying magnetic field along the junction. The resistance asymmetry is strongly affected by corrugation due to the varying mobility along different crystallographic directions. We compare our results with a recent transport measurement.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000266149900011 Publication Date (up) 2009-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.554 Times cited 1 Open Access
Notes Approved Most recent IF: 1.554; 2009 IF: 1.837
Call Number UA @ lucian @ c:irua:77580 Serial 1897
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Author Cao, S.; Tirry, W.; van den Broek, W.; Schryvers, D.
Title 3D reconstruction of Ni4Ti3 precipitates in a Ni51Ti49 alloy in a FIB/SEM dual-beam system Type A1 Journal article
Year 2008 Publication Materials science forum Abbreviated Journal
Volume 583 Issue Pages 277-284
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Ni4Ti3 precipitates play an important role in the shape memory and superelastic behaviour of thermo-mechanically treated Ni-Ti material. The 3D morphology and distribution of such precipitates with lenticular shape and rhombohedral atomic structure in the austenitic B2 matrix of a binary Ni-rich Ni-Ti alloy has been elucidated via a slice view procedure in a Dual-Beam FIB/SEM system. With the sequence of cross-section SE images obtained from the SEM, a 3D reconstruction has been achieved after proper alignment and image processing, from which both qualitative and quantitative analysis can be performed. Careful imaging is needed to ensure that all variants of the precipitates are observed with equal probability, regardless sample orientation. Moreover, due to the weak contrast of the precipitates, proper imaging conditions need to be selected to allow for semi-automated image treatment. Finally, a volume ratio of 10.2% for the Ni4Ti3 precipitates could be calculated, summed over all variants, which yields a net composition of Ni50.36Ti49.64 for the matrix, leading to an increase of 113 degrees for the martensitic start temperature Ms. Also, the expected relative orientation of the different variants of the precipitates could be confirmed. In the near future, other quantitative measures on the distribution of the precipitates can be expected.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos Publication Date (up) 2009-03-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1662-9752; ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Multimat; Fwo Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:77454 Serial 16
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Author van der Snickt, G.; Dik, J.; Cotte, M.; Janssens, K.; Jaroszewicz, J.; de Nolf, W.; Groenewegen, J.; van der Loeff, L.
Title Characterization of a degraded cadmium yellow (CdS) pigment in an oil painting by means of synchrotron radiation based X-ray techniques Type A1 Journal article
Year 2009 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 81 Issue 7 Pages 2600-2610
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract On several paintings of James Ensor (1860−1949), a gradual fading of originally bright yellow areas, painted with the pigment cadmium yellow (CdS), is observed. Additionally, in some areas exposed to light, the formation of small white-colored globules on top of the original paint surface is observed. In this paper the chemical transformation leading to the color change and to the formation of the globules is elucidated. Microscopic X-ray absorption near-edge spectroscopy (ì-XANES) experiments show that sulfur, originally present in sulfidic form (S2−), is oxidized during the transformation to the sulfate form (S6+). Upon formation (at or immediately below the surface), the highly soluble cadmium sulfate is assumed to be transported to the surface in solution and reprecipitates there, forming the whitish globules. The presence of cadmium sulfate (CdSO4·2H2O) and ammonium cadmium sulfate [(NH4)2Cd(SO4)2] at the surface is confirmed by microscopic X-ray diffraction measurements, where the latter salt is suspected to result from a secondary reaction of cadmium sulfate with ammonia. Measurements performed on cross sections reveal that the oxidation front has penetrated into the yellow paint down to ca. 1−2 ìm. The morphology and elemental distribution of the paint and degradation product were examined by means of scanning electron microscopy equipped with an energy-dispersive spectrometer (SEM-EDS) and synchrotron radiation based micro-X-ray fluorescence spectrometry (SR ì-XRF). In addition, ultraviolet-induced visible fluorescence photography (UIVFP) revealed itself to be a straightforward technique for documenting the occurrence of this specific kind of degradation on a macroscale by painting conservators.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000264759400025 Publication Date (up) 2009-03-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 91 Open Access
Notes Approved Most recent IF: 6.32; 2009 IF: 5.214
Call Number UA @ admin @ c:irua:76415 Serial 5501
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Author Schowalter, M.; Rosenauer, A.; Titantah, J.T.; Lamoen, D.
Title Temperature-dependent Debye-Waller factors for semiconductors with the wurtzite-type structure Type A1 Journal article
Year 2009 Publication Acta crystallographica: section A: foundations of crystallography Abbreviated Journal Acta Crystallogr A
Volume 65 Issue Pages 227-231
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We computed Debye-Waller factors in the temperature range from 0.1 to 1000 K for AlN, GaN, InN, ZnO and CdO with the wurtzite-type structure. The Debye-Waller factors were derived from phonon densities of states obtained from Hellmann-Feynman forces computed within the density-functional-theory formalism. The temperature dependences of the Debye-Waller factors were fitted and fit parameters are given.
Address
Corporate Author Thesis
Publisher Place of Publication Copenhagen Editor
Language Wos 000264927100006 Publication Date (up) 2009-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0108-7673; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.725 Times cited 23 Open Access
Notes Fwo G.0425.05; Esteem 026019 Approved Most recent IF: 5.725; 2009 IF: 49.926
Call Number UA @ lucian @ c:irua:74565 Serial 3497
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Author Vandevoorde, D.; Pamplona, M.; Schalm, O.; Vanhellemont, Y.; Cnudde, V.; Verhaeven, E.
Title Contact sponge method : performance of a promising tool for measuring the initial water absorption Type A1 Journal article
Year 2009 Publication Journal of cultural heritage Abbreviated Journal
Volume 10 Issue 1 Pages 41-47
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Porous limestone and mortar are able to absorb large quantities of water. This phenomenon will accelerate the deterioration of the material. In such cases, the material might be treated with a hydrophobic product, which creates a superficial layer that hampers the penetration of water. In order to decide if such a treatment should be applied or not, the water absorbing behaviour of the material should be measured. With the same measuring technique the efficiency of the hydrophobic barrier can be evaluated. Moreover, it allows the monitoring of such barriers as a function of time. At the same time, the water absorption of porous stone material is an indication of the degree of deterioration and its sensitivity to future deterioration. Up to now, two different measuring techniques exist, but one can only be used in laboratory and the other, which can be operated in laboratory as well as in situ, is not always reliable for in situ analyses. This article proposes an alternative method: the contact sponge method. This recently developed method was tested on non-treated porous stone materials in a laboratory environment in order to evaluate its performance in comparison with the two existing methods.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000264831900005 Publication Date (up) 2009-03-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1296-2074 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:115023 Serial 7728
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Author Ghekiere, P.; Mahieu, S.; De Winter, G.; De Gryse, R.; Depla, D.; Lebedev, O.I.
Title Growth mechanism of biaxially aligned magnesium oxide deposited by unbalanced magnetron sputtering Type A1 Journal article
Year 2005 Publication Diffusion and defect data : solid state data : part B : solid state phenomena T2 – 2nd International Conference on Texture and Anisotropy of Polycrystals, JUL 07-09, 2004, Metz, FRANCE Abbreviated Journal
Volume 105 Issue Pages 433-438
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract For many years magnesium oxide (MgO) has been a topic of research as buffer layer for high-temperature superconducting copper oxides and as protective layer in plasma display panels. Since epitaxial growth of MgO is expensive, time consuming and size restricted, other techniques have been developed to grow highly oriented MgO layers for industrial processes. MgO thin films were deposited on a tilted polycrystalline substrate by reactive sputtering using an unbalanced magnetron. By varying different deposition parameters, it is possible to grow biaxially aligned MgO layers, i.e. layers with both out-of-plane and in-plane alignment. XRD measurements were performed to examine the crystallographic structure of the thin film. The preferential out-of-plane orientation is analysed by angular scans using the peak intensity of different reflections while the in-plane orientation is determined by (002) pole figures. Fully [111] out-of-plane oriented layers were grown with a strong in-plane alignment. SEM and TEM measurements were performed to reveal the topographical and cross-sectional microstructure and to investigate the texture evolution of the MgO layers. Evolutionary columnar growth and a roof-tile surface have been observed.
Address
Corporate Author Thesis
Publisher Place of Publication Vaduz Editor
Language Wos 000230478000069 Publication Date (up) 2009-03-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1662-9779; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 5 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:104085 Serial 1392
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Author Bals, S.; Batenburg, K.J.; Liang, D.; Lebedev, O.; Van Tendeloo, G.; Aerts, A.; Martens, J.A.; Kirschhock, C.E.
Title Quantitative three-dimensional modeling of zeotile through discrete electron tomography Type A1 Journal article
Year 2009 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 131 Issue 13 Pages 4769-4773
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Discrete electron tomography is a new approach for three-dimensional reconstruction of nanoscale objects. The technique exploits prior knowledge of the object to be reconstructed, which results in an improvement of the quality of the reconstructions. Through the combination of conventional transmission electron microscopy and discrete electron tomography with a model-based approach, quantitative structure determination becomes possible. In the present work, this approach is used to unravel the building scheme of Zeotile-4, a silica material with two levels of structural order. The layer sequence of slab-shaped building units could be identified. Successive layers were found to be related by a rotation of 120°, resulting in a hexagonal space group. The Zeotile-4 material is a demonstration of the concept of successive structuring of silica at two levels. At the first level, the colloid chemical properties of Silicalite-1 precursors are exploited to create building units with a slablike geometry. At the second level, the slablike units are tiled using a triblock copolymer to serve as a mesoscale structuring agent.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000264806300050 Publication Date (up) 2009-03-16
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 58 Open Access
Notes Fwo; Iap; Esteem 026019 Approved Most recent IF: 13.858; 2009 IF: 8.580
Call Number UA @ lucian @ c:irua:76393 Serial 2767
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Author Smeulders, G.; Meynen, V.; van Baelen, G.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Maes, B.U.W.; Cool, P.
Title Rapid microwave-assisted synthesis of benzene bridged periodic mesoporous organosilicas Type A1 Journal article
Year 2009 Publication Journal of materials chemistry Abbreviated Journal J Mater Chem
Volume 19 Issue 19 Pages 3042-3048
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY)
Abstract Following extended use in organic chemistry, microwave-assisted synthesis is gaining more importance in the field of inorganic chemistry, especially for the synthesis of nanoporous materials. It offers some major advantages such as a significant shortening of the synthesis time and an improved promotion of nucleation. In the research here reported, microwave technology is applied for the synthesis of benzene bridged PMOs (periodic mesoporous organosilicas). PMOs are one of the latest innovations in the field of hybrid ordered mesoporous materials and have attracted much attention because of their feasibility in electronics, catalysis, separation and sorption applications. The different synthesis steps (stirring, aging and extraction) of the classical PMO synthesis are replaced by microwave-assisted synthesis steps. The characteristics of the as-synthesized materials are evaluated by X-ray diffraction, N2-sorption, thermogravimetric analysis, scanning- and transmission electron microscopy. The microwave-assisted synthesis drastically reduces the synthesis time by more than 40 hours without any loss in structural properties, such as mesoscale and molecular ordering. The porosity of the PMO materials has even been improved by more than 25%. Moreover, the number of handling/transfer steps and amounts of chemicals and waste are drastically reduced. The study also shows that there is a clear time (1 to 3 hours) and temperature frame (373 K to 403 K) wherein synthesis of benzene bridged PMO is optimal. In conclusion, the microwave-assisted synthesis pathway allows an improved material to be obtained in a more economical way i.e. a much shorter time with fewer chemicals and less waste.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000265919300024 Publication Date (up) 2009-03-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0959-9428;1364-5501; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 20 Open Access
Notes Fwo; Iwt Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:76844 Serial 2810
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Author Tambuyzer, B.R.; Bergwerf, I.; de Vocht, N.; Reekmans, K.; Daans, J.; Jorens, P.G.; Goossens, H.; Ysebaert, D.K.; Chatterjee, S.; Van Marck, E.; Berneman, Z.N.; Ponsaerts, P.
Title Allogeneic stromal cell implantation in brain tissue leads to robust microglial activation Type A1 Journal article
Year 2009 Publication Immunology and cell biology Abbreviated Journal Immunol Cell Biol
Volume Issue Pages
Keywords A1 Journal article; Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP); Bio-Imaging lab; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Although adult and embryonic stem cell-based therapy for central nervous system (CNS) injury is being developed worldwide, less attention is given to the immunological aspects of allogeneic cell implantation in the CNS. The latter is of major importance because, from a practical point of view, future stem cell-based therapy for CNS injury will likely be performed using well-characterised allogeneic stem cell populations. In this study, we aimed to further describe the immunological mechanism leading to rejection of allogeneic bone marrow-derived stromal cells (BM-SC) after implantation in murine CNS. For this, we first investigated the impact of autologous and allogeneic BM-SC on microglia activation in vitro. Although the results indicate that both autologous and allogeneic BM-SC do not activate microglia themselves in vitro, they also do not inhibit activation of microglia after exogenous stimuli in vitro. Next, we investigated the impact of allogeneic BM-SC on microglia activation in vivo. In contrast to the in vitro observations, microglia become highly activated in vivo after implantation of allogeneic BM-SC in the CNS of immune-competent mice. Moreover, our results suggest that microglia, rather than T-cells, are the major contributors to allograft rejection in the CNS.
Address
Corporate Author Thesis
Publisher Place of Publication Adelaide Editor
Language Wos 000266208800003 Publication Date (up) 2009-03-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0818-9641 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.557 Times cited 31 Open Access
Notes Approved Most recent IF: 4.557; 2009 IF: 4.200
Call Number UA @ lucian @ c:irua:74903 Serial 4515
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Author Van Aert, S.; Bals, S.; Chang, L.Y.; den Dekker, A.J.; Kirkland, A.I.; Van Dyck, D.; Van Tendeloo, G.
Title The benefits of statistical parameter estimation theory for quantitative interpretation of electron microscopy data Type H1 Book chapter
Year 2008 Publication Abbreviated Journal
Volume Issue Pages 97-98
Keywords H1 Book chapter; Electron microscopy for materials research (EMAT); Vision lab
Abstract
Address
Corporate Author Thesis
Publisher Springer Place of Publication Berlin Editor
Language Wos Publication Date (up) 2009-03-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 978-3-540-85154-7 Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:136865 Serial 4493
Permanent link to this record
 

 
Author Tomecka, D.M.; Kamieniarz, G.; Partoens, B.; Peeters, F.M.
Title Ground state configurations and melting of two-dimensional non-uniformly charged classical clusters Type A1 Journal article
Year 2009 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 21 Issue 15 Pages 155301,1-155301,7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We consider classical two-dimensional (2D) Coulomb clusters consisting of two species containing five particles with charge q1 and five with charge q2, respectively. Using Monte Carlo and molecular dynamics (MD) simulations, we investigated the ground state configurations as well as radial and angular displacements of particles as a function of temperature and their dependence on the ratio q = q2/q1. We found new configurations and a new multi-step melting behavior for q sufficiently different from the uniform charge limit q = 1.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000264708600007 Publication Date (up) 2009-03-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 2 Open Access
Notes Approved Most recent IF: 2.649; 2009 IF: 1.964
Call Number UA @ lucian @ c:irua:76412 Serial 1384
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Author Müller, K.; Schowalter, M.; Jansen, J.; Tsuda, K.; Titantah, J.; Lamoen, D.; Rosenauer, A.
Title Refinement of the 200 structure factor for GaAs using parallel and convergent beam electron nanodiffraction data Type A1 Journal article
Year 2009 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 109 Issue 7 Pages 802-814
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We present a new method to measure structure factors from electron spot diffraction patterns recorded under almost parallel illumination in transmission electron microscopes. Bloch wave refinement routines have been developed to refine the crystal thickness, its orientation and structure factors by comparison of experimentally recorded and calculated intensities. Our method requires a modicum of computational effort, making it suitable for contemporary personal computers. Frozen lattice and Bloch wave simulations of GaAs diffraction patterns are used to derive optimised experimental conditions. Systematic errors are estimated from the application of the method to simulated diffraction patterns and rules for the recognition of physically reasonable initial refinement conditions are derived. The method is applied to the measurement of the 200 structure factor for GaAs. We found that the influence of inelastically scattered electrons is negligible. Additionally, we measured the 200 structure factor from zero loss filtered two-dimensional convergent beam electron diffraction patterns. The precision of both methods is found to be comparable and the results agree well with each other. A deviation of more than 20% from isolated atom scattering data is observed, whereas close agreement is found with structure factors obtained from density functional theory [A. Rosenauer, M. Schowalter, F. Glas, D. Lamoen, Phys. Rev. B 72 (2005), 085326-1], which account for the redistribution of electrons due to chemical bonding via modified atomic scattering amplitudes.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000266787900005 Publication Date (up) 2009-03-23
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 8 Open Access
Notes Fwo; G.0425.05; Esteem; Ant 200611271505 Approved Most recent IF: 2.843; 2009 IF: 2.067
Call Number UA @ lucian @ c:irua:77361 Serial 2856
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Author de Backer, J.W.; Vos, W.G.; Burnell, P.; Verhulst, S.L.; Salmon, P.; de Clerck, N.; de Backer, W.
Title Study of the variability in upper and lower airway morphology in Sprague-Dawley rats using modern micro-CT scan-based segmentation techniques Type A1 Journal article
Year 2009 Publication The anatomical record: advances in integrative anatomy and evolutionary biology Abbreviated Journal Anat Rec
Volume 292 Issue 5 Pages 720-727
Keywords A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Animal models are being used extensively in pre-clinical and safety assessment studies to assess the effectiveness and safety of new chemical entities and delivery systems. Although never entirely replacing the need for animal testing, the use of computer simulations could eventually reduce the amount of animals needed for research purposes and refine the data acquired from the animal studies. Computational fluid dynamics is a powerful tool that makes it possible to simulate flow and particle behavior in animal or patient-specific respiratory models, for purposes of inhaled delivery. This tool requires an accurate representation of the respiratory system, respiration and dose delivery attributes. The aim of this study is to develop a representative airway model of the Sprague-Dawley rat using static and dynamic micro-CT scans. The entire respiratory tract was modeled, from the snout and nares down to the central airways at the point where no distinction could be made between intraluminal air and the surrounding tissue. For the selection of the representative model, variables such as upper airway movement, segmentation length, airway volume and size are taken into account. Dynamic scans of the nostril region were used to illustrate the characteristic morphology of this region in anaesthetized animals. It could be concluded from this study that it was possible to construct a highly detailed representative model of a Sprague-Dawley rat based on imaging modalities such as micro-CT scans
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000265766000010 Publication Date (up) 2009-03-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-8486;1932-8494; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.431 Times cited 16 Open Access
Notes Approved Most recent IF: 1.431; 2009 IF: 1.490
Call Number UA @ lucian @ c:irua:76455 Serial 3342
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Author Zelaya, E.; Tolley, A.; Condo, A.M.; Schumacher, G.
Title Swift heavy ion irradiation of Cu-Zn-Al and Cu-Al-Ni alloys Type A1 Journal article
Year 2009 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 21 Issue 18 Pages 185009-185009,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The effects produced by swift heavy ions in the martensitic (18R) and austenitic phase (beta) of Cu based shape memory alloys were characterized. Single crystal samples with a surface normal close to [210](18R) and [001](beta) were irradiated with 200 MeV of Kr(15+), 230 MeV of Xe(15+), 350 and 600 MeV of Au(26+) and Au(29+). Changes in the microstructure were studied with transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). It was found that swift heavy ion irradiation induced nanometer sized defects in the 18R martensitic phase. In contrast, a hexagonal close-packed phase formed on the irradiated surface of beta phase samples. HRTEM images of the nanometer sized defects observed in the 18R martensitic phase were compared with computer simulated images in order to interpret the origin of the observed contrast. The best agreement was obtained when the defects were assumed to consist of local composition modulations.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000264934400014 Publication Date (up) 2009-03-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 8 Open Access
Notes Approved Most recent IF: 2.649; 2009 IF: 1.964
Call Number UA @ lucian @ c:irua:94551 Serial 3399
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Author Ariskin, D.A.; Schweigert, I.V.; Alexandrov, A.L.; Bogaerts, A.; Peeters, F.M.
Title Modeling of chemical processes in the low pressure capacitive radio frequency discharges in a mixture of Ar/C2H2 Type A1 Journal article
Year 2009 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 105 Issue 6 Pages 063305,1-063305,9
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We study the properties of a capacitive 13.56 MHz discharge with a mixture of Ar/C<sub>2</sub>H<sub>2</sub> taking into account the plasmochemistry and growth of heavy hydrocarbons. A hybrid model was developed to combine the kinetic description for electron motion and the fluid approach for negative and positive ion transports and plasmochemical processes. A significant change in plasma parameters related to injection of 5.8% portion of acetylene in argon was observed and analyzed. We found that the electronegativity of the mixture is about 30%. The densities of negatively and positively charged heavy hydrocarbons are sufficiently large to be precursors for the formation of nanoparticles in the discharge volume.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000264774000059 Publication Date (up) 2009-03-26
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 21 Open Access
Notes Approved Most recent IF: 2.068; 2009 IF: 2.072
Call Number UA @ lucian @ c:irua:74496 Serial 2121
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Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.; Pereira, J.M.
Title Bilayer graphene with single and multiple electrostatic barriers: band structure and transmission Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 79 Issue 15 Pages 155402,1-155402,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We evaluate the electronic transmission and conductance in bilayer graphene through a finite number of potential barriers. Further, we evaluate the dispersion relation in a bilayer graphene superlattice with a periodic potential applied to both layers. As a model we use the tight-binding Hamiltonian in the continuum approximation. For zero bias the dispersion relation shows a finite gap for carriers with zero momentum in the direction parallel to the barriers. This is in contrast to single-layer graphene where no such gap was found. A gap also appears for a finite bias. Numerical results for the energy spectrum, conductance, and the density of states are presented and contrasted with those pertaining to single-layer graphene.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000265944200091 Publication Date (up) 2009-04-01
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 74 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:77025 Serial 235
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Author Engbarth, M.; Milošević, M.V.; Bending, S.J.; Nasirpouri, F.
Title Geometry-guided flux behaviour in superconducting Pb microcrystals Type A1 Journal article
Year 2009 Publication Journal of physics : conference series Abbreviated Journal
Volume 150 Issue 5 Pages 052048
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Electrochemistry offers highly flexible routes to fabrication of a wide variety of mesostructures, including three-dimensional (3D) crystallites, thin films and nanowires. Using this method we have grown various 3D superconducting Pb mesostructures with vastly different morphologies. We present here results on a truncated(half)-icosahedron with a hexagonal base and a tripod structure with a triangular base. Using Hall probe magnetometry we have obtained magnetisation curves for these structures at several temperatures and see evidence of geometry-driven flux entry and exit as well as flux trapping caused by specific sample geometries. We also observe behaviour that we interpret in terms of the formation of giant vortices, bearing in mind that bulk Pb is a type-I superconducting material.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos Publication Date (up) 2009-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6588;1742-6596; ISBN Additional Links UA library record
Impact Factor Times cited 1 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:106138 Serial 1332
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Author Bending, S.J.; Neal, J.S.; Milošević, M.V.; Potenza, A.; san Emeterio, L.; Marrows, C.H.
Title Vortex-antivortex 'molecular crystals' in hybrid ferromagnet/superconductor structures Type A1 Journal article
Year 2009 Publication Journal of physics : conference series Abbreviated Journal
Volume 150 Issue 5 Pages 052019
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We have used high resolution Hall probe microscopy to image vortex-antivortex (V-AV) 'molecules' induced in superconducting Pb films by the stray fields from square arrays of ferromagnetic Co/Pt dots. We have directly observed spontaneous V-AV pairs and studied how they interact with added 'free' (anti)fluxons in an applied magnetic field. We observe a rich variety of subtle phenomena arising from competing symmetries in our system which can either drive added antivortices to join AV shells around nanomagnets or stabilise the translationally symmetric AV lattice between the dots. Added vortices annihilate AV shells, leading eventually to a stable 'nulling' state with no free fluxons, which should exhibit a strongly (field-)enhanced critical current. At higher densities we actually observe vortex shells around the magnets, stabilised by the asymmetric anti-pinning potential. Our experimental findings are in good agreement with Ginzburg-Landau calculations.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos Publication Date (up) 2009-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6588;1742-6596; ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:106136 Serial 3855
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Author Connolly, M.R.; Milošević, M.V.; Bending, S.J.; Clem, J.R.; Tamegai, T.
Title Vortex 'puddles' and magic vortex numbers in mesoscopic superconducting disks Type A1 Journal article
Year 2009 Publication Journal of physics : conference series Abbreviated Journal
Volume 150 Issue 5 Pages 052039
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The magnetic properties of a superconducting disk change dramatically when its dimensions become mesoscopic. Unlike large disks, where the screening currents induced by an applied magnetic field are strong enough to force vortices to accumulate in a 'puddle' at the centre, in a mesoscopic disk the interaction between one of these vortices and the edge currents can be comparable to the intervortex repulsion, resulting in a destruction of the ordered triangular vortex lattice structure at the centre. Vortices instead form clusters which adopt polygonal and shell-like structures which exhibit magic number states similar to those of charged particles in a confining potential, and electrons in artificial atoms. We have fabricated mesoscopic high temperature superconducting Bi2Sr2CaCu2O8+δ disks and investigated their magnetic properties using magneto-optical imaging (MOI) and high resolution scanning Hall probe microscopy (SHPM). The temperature dependence of the vortex penetration field measured using MOI is in excellent agreement with models of the thermal excitation of pancake vortices over edge barriers. The growth of the central vortex puddle has been directly imaged using SHPM and magic vortex numbers showing higher stability have been correlated with abrupt jumps in the measured local magnetisation curves.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos Publication Date (up) 2009-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6588;1742-6596; ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:106137 Serial 3881
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Author Eckert, M.; Neyts, E.; Bogaerts, A.
Title Modeling adatom surface processes during crystal growth: a new implementation of the Metropolis Monte Carlo algorithm Type A1 Journal article
Year 2009 Publication CrystEngComm Abbreviated Journal Crystengcomm
Volume 11 Issue 8 Pages 1597-1608
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this paper, a new implementation of the Metropolis Monte Carlo (MMC) algorithm is presented. When combining the MMC model with a molecular dynamics (MD) code, crystal growth by plasma-enhanced chemical vapor deposition can be simulated. As the MD part simulates impacts of growth species onto the surface on a time scale of picoseconds, the MMC algorithm simulates the slower adatom surface processes. The implementation includes a criterion for the selection of atoms that are allowed to be displaced during the simulation, and a criterion of after how many MMC cycles the simulation is stopped. We performed combined MD-MMC simulations for hydrocarbon species that are important for the growth of ultrananocrystalline diamond (UNCD) films at partially hydrogenated diamond surfaces, since this implementation is part of a study of the growth mechanisms of (ultra)nanocrystalline diamond films. Exemplary for adatom arrangements during the growth of UNCD, the adatom surface behavior of C and C2H2 at diamond (111)1 × 1, C and C4H2 at diamond (111)1 × 1 and C3 at diamond (100)2 × 1 has been investigated. For all cases, the diamond crystal structure is pursued under the influence of MMC simulation. Additional longer time-scale MD simulations put forward very similar structures, verifying the MMC algorithm. Nevertheless, the MMC simulation time is typically one order of magnitude shorter than the MD simulation time.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000268184300021 Publication Date (up) 2009-04-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1466-8033; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.474 Times cited 15 Open Access
Notes Approved Most recent IF: 3.474; 2009 IF: 4.183
Call Number UA @ lucian @ c:irua:77374 Serial 2106
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Author Nakiboglu, G.; Gorlé, C.; Horvath, I.; van Beeck, J.; Blocken, B.
Title Stack gas dispersion measurements with large scale-PIV, aspiration probes and light scattering techniques and comparison with CFD Type A1 Journal article
Year 2009 Publication Atmospheric environment : an international journal Abbreviated Journal Atmos Environ
Volume 43 Issue 21 Pages 3396-3406
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The main purpose of this research is to manage simultaneous measurement of velocity and concentration in large cross-sections by recording and processing images of cloud structures to provide more detailed information for e.g. validation of CFD simulations. Dispersion from an isolated stack in an Atmospheric Boundary Layer (ABL) was chosen as the test case and investigated both experimentally and numerically in a wind tunnel. Large Scale-Particle Image Velocimetry (LS-PIV), which records cloud structures instead of individual particles, was used to obtain the velocity field in a vertical plane. The concentration field was determined by two methods: Aspiration Probe (AP) measurements and Light Scattering Technique (LST). In the latter approach, the same set of images used in the LS-PIV was employed. The test case was also simulated using the CFD solver FLUENT 6.3. Comparison between AP measurements and CFD revealed that there is good agreement when using a turbulent Schmidt number of 0.4. For the LST measurements, a non-linear relation between concentration and light intensity was observed and a hyperbolic-based function is proposed as correction function. After applying this correction function, a close agreement between CFD and LST measurements is obtained. (C) 2009 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000267529600013 Publication Date (up) 2009-04-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1352-2310; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.629 Times cited 15 Open Access
Notes Approved Most recent IF: 3.629; 2009 IF: 3.139
Call Number UA @ lucian @ c:irua:94531 Serial 3147
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Author Moshnyaga, V.; Gehrke, K.; Sudheendra, L.; Belenchuk, A.; Raabe, S.; Shapoval, O.; Verbeeck, J.; Van Tendeloo, G.; Samwer, K.
Title Electrical nonlinearity in colossal magnetoresistance manganite films: relevance of correlated polarons Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 79 Issue 13 Pages 134413,1-134413,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The metal-insulator (MI) transition in epitaxial thin films of La0.75Ca0.25MnO3 (LCMO) is accompanied by the appearance of an intrinsic electrical nonlinearity. The latter, probed by electrical third harmonic voltage, U3, or resistance, R3=dU3/dJ, is drastically enhanced in the vicinity of the MI transition, TMI=267 K. Applied magnetic field, B=5 T, suppresses the nonlinearity, resulting in a huge nonlinear CMR3(TMI)~105%. R3 shows a peculiar low-frequency (1 kHz) dependence, R3~(-0)n, with exponent, n, changing across the MI transition from n~1,52 for TTMI to n=1 (T<TMI). The observed electrical nonlinearity in LCMO reflects the behavior of correlated polarons, the number of which dramatically enhances in the vicinity of TMI. We argued that correlated polarons, considered as electric-elastic quadrupoles, provide a nonlinear (quadratic) coupling to the electric field, yielding a third harmonic electric nonlinearity in LCMO. The reference film of La0.7Sr0.3MnO3 (LSMO), a prototypic double exchange system with second-order phase transition, is characterized as a linear metallic material in the whole range of temperatures (T=10400 K), magnetic fields (B=05 T), and frequencies (=11000 Hz).
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000265942800074 Publication Date (up) 2009-04-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 28 Open Access
Notes Esteem 026019 Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:77022UA @ admin @ c:irua:77022 Serial 893
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Author Nikolaev, A.V.; Verberck, B.; Ionova, G.V.
Title Molecular interaction energies and optimal configuration of a cubane dimer Type A1 Journal article
Year 2010 Publication International journal of quantum chemistry Abbreviated Journal Int J Quantum Chem
Volume 110 Issue 5 Pages 1063-1069
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We have studied the dependence of the binding energy of a cubane dimer on the mutual orientation of and the distance between the composing monomers employing the second-order Møller-Plesset perturbation scheme (MP2) with the cc-pVDZ molecular basis set. We have found that the MP2 contribution from the molecular correlations is responsible for the bound state of the cubane dimer, whereas the Hartree-Fock contribution remains anti-bonding at all intermolecular distances. Starting with two molecules in the standard orientation and centers of mass at (0,0,0) and (0,0,d), respectively, the maximal binding energy is found at d = 5.125 Å and one of the monomers rotated by 45° about the z-axis. This configuration implies that the hydrogen atoms belonging to different monomers tend to repel each other. The results are in agreement with experimental data on the optimal packing of cubane molecules in the solid state.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000274720000011 Publication Date (up) 2009-04-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-7608;1097-461X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.92 Times cited 1 Open Access
Notes ; ; Approved Most recent IF: 2.92; 2010 IF: 1.302
Call Number UA @ lucian @ c:irua:81944 Serial 2179
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Author Hadermann, J.; Abakumov, A.M.; Van Rompaey, S.; Mankevich, A.S.; Korsakov, I.E.
Title Comment on ALaMn2O6-y (A = K, Rb): novel ferromagnetic manganites exhibiting negative giant magnetoresistance Type Editorial
Year 2009 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 21 Issue 9 Pages 2000-2001
Keywords Editorial; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000265781000036 Publication Date (up) 2009-04-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 4 Open Access
Notes Approved Most recent IF: 9.466; 2009 IF: 5.368
Call Number UA @ lucian @ c:irua:77055 Serial 411
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Author Tinck, S.; Boullart, W.; Bogaerts, A.
Title Investigation of etching and deposition processes of Cl2/O2/Ar inductively coupled plasmas on silicon by means of plasmasurface simulations and experiments Type A1 Journal article
Year 2009 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 42 Issue Pages 095204,1-095204,13
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this paper, a simulation method is described to predict the etching behaviour of Cl2/O2/Ar inductively coupled plasmas on a Si substrate, as used in shallow trench isolation for the production of electronic devices. The hybrid plasma equipment model (HPEM) developed by Kushner et al is applied to calculate the plasma characteristics in the reactor chamber and two additional Monte Carlo simulations are performed to predict the fluxes, angles and energy of the plasma species bombarding the Si substrate, as well as the resulting surface processes such as etching and deposition. The simulations are performed for a wide variety of operating conditions such as gas composition, chamber pressure, power deposition and substrate bias. It is predicted by the simulations that when the fraction of oxygen in the gas mixture is too high, the oxidation of the Si substrate is superior to the etching of Si by chlorine species, resulting in an etch rate close to zero as is also observed in the experiments.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000265531000030 Publication Date (up) 2009-04-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 23 Open Access
Notes Approved Most recent IF: 2.588; 2009 IF: 2.083
Call Number UA @ lucian @ c:irua:75601 Serial 1731
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