Records |
Author |
Yusupov, M.; Bultinck, E.; Depla, D.; Bogaerts, A. |
Title |
Behavior of electrons in a dual-magnetron sputter deposition system : a Monte Carlo model |
Type |
A1 Journal article |
Year |
2011 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
13 |
Issue |
|
Pages |
033018-033018,17 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A Monte Carlo model has been developed for investigating the electron behavior in a dual-magnetron sputter deposition system. To describe the three-dimensional (3D) geometry, different reference frames, i.e. a local and a global coordinate system, were used. In this study, the influence of both closed and mirror magnetic field configurations on the plasma properties is investigated. In the case of a closed magnetic field configuration, the calculated electron trajectories show that if an electron is emitted in (or near) the center of the cathode, where the influence of the magnetic field is low, it is able to travel from one magnetron to the other. On the other hand, when an electron is created at the race track area, it is more or less trapped in the strong magnetic field and cannot easily escape to the second magnetron region. In the case of a mirror magnetic field configuration, irrespective of where the electron is emitted from the cathode, it cannot travel from one magnetron to the other because the magnetic field lines guide the electron to the substrate. Moreover, the electron density and electron impact ionization rate have been calculated and studied in detail for both configurations. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000289064600001 |
Publication Date |
2011-03-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2011 IF: 4.177 |
Call Number |
UA @ lucian @ c:irua:87544 |
Serial |
224 |
Permanent link to this record |
|
|
|
Author |
Zeng, Y.I.; Menghini, M.; Li, D.Y.; Lin, S.S.; Ye, Z.Z.; Hadermann, J.; Moorkens, T.; Seo, J.W.; Locquet, J.-P.; van Haesendonck, C. |
Title |
Unexpected optical response of single ZnO nanowires probed using controllable electrical contacts |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
13 |
Issue |
15 |
Pages |
6931-6935 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Relying on combined electron-beam lithography and lift-off methods Au/Ti bilayer electrical contacts were attached to individual ZnO nanowires (NWs) that were grown by a vapor phase deposition method. Reliable Schottky-type as well as ohmic contacts were obtained depending on whether or not an ion milling process was used. The response of the ZnO NWs to ultraviolet light was found to be sensitive to the type of contacts. The intrinsic electronic properties of the ZnO NWs were studied in a field-effect transistor configuration. The transfer characteristics, including gate threshold voltage, hysteresis and operational mode, were demonstrated to unexpectedly respond to visible light. The origin of this effect could be accounted for by the presence of point defects in the ZnO NWs. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000288951000019 |
Publication Date |
2011-03-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.123; 2011 IF: 3.573 |
Call Number |
UA @ lucian @ c:irua:89378 |
Serial |
3807 |
Permanent link to this record |
|
|
|
Author |
Verberck, B.; Tarakina, N.V. |
Title |
Tubular fullerenes inside carbon nanotubes : optimal molecular orientation versus tube radius |
Type |
A1 Journal article |
Year |
2011 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
80 |
Issue |
3 |
Pages |
355-362 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
We present an investigation of the orientations and positions of tubular fullerene molecules (C90, ..., C200) encapsulated in single-walled carbon nanotubes (SWCNT), a series of so-called fullerene nanopeapods. We find that increasing the tube radius leads to the following succession of energetically stable regimes: (1) lying molecules positioned on the tube's long axis; (2) tilted molecules on the tube's long axis; and (3) lying molecules shifted away from the tube's long axis. As opposed to C70 and C80 molecules encapsulated in a SWCNT, standing orientations do not develop. Our results are relevant for the possible application of molecular-orientation-dependent electronic properties of fullerene nanopeapods, and also for the interpretation of future experiments on double-walled carbon nanotube formation by annealing fullerene peapod systems. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000289576200010 |
Publication Date |
2011-03-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6028;1434-6036; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.461 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was financially supported by the Research Foundation – Flanders (FWO-VI). B.V. is a Postdoctoral Fellow of the Research Foundation – Flanders (FWO-VI). ; |
Approved |
Most recent IF: 1.461; 2011 IF: 1.534 |
Call Number |
UA @ lucian @ c:irua:89286 |
Serial |
3738 |
Permanent link to this record |
|
|
|
Author |
Földi, P.; Szaszkó-Bogár, V.; Peeters, F.M. |
Title |
High-temperature conductance of a two-dimensional superlattice controlled by spin-orbit interaction |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
11 |
Pages |
115313-115313,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Rashba-type spin-orbit interaction (SOI) controlled band structure of a two-dimensional superlattice allows for the modulation of the conductance of finite size devices by changing the strength of the SOI. We consider rectangular arrays and find that the temperature dependence of the conductance disappears for high temperatures, but the strength of the SOI still affects the conductance at these temperatures. The modulation effect can be seen even in the presence of strong dephasing, which can be important for practical applications. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000288242800007 |
Publication Date |
2011-03-11 |
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 |
8 |
Open Access |
|
Notes |
; We thank M. G. Benedict and F. Bartha for useful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the Hungarian Scientific Research Fund (OTKA) under Contracts No. T81364 and M045596 and by the “TAMOP-4.2.1/B-09/1/KONV-2010-0005 project: Creating the Center of Excellence at the University of Szeged” supported by the EU and the European Regional Development Fund. P.F. was supported by a J. Bolyai grant of the Hungarian Academy of Sciences. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:88778 |
Serial |
1466 |
Permanent link to this record |
|
|
|
Author |
Boullay, P.; David, A.; Sheets, W.C.; Lüders, U.; Prellier, W.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.; Gatel, C.; Vincze, G.; Radi, Z. |
Title |
Microstructure and interface studies of LaVO3/SrVO3 superlattices |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
12 |
Pages |
125403-125403,6 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The structure and interface characteristics of (LaVO3)6m(SrVO3)m superlattices deposited on a (100)-SrTiO3 substrate were studied using transmission electron microscopy (TEM). Cross-section TEM studies revealed that both LaVO3 (LVO) and SrVO3 (SVO) layers are good single-crystal quality and epitaxially grown with respect to the substrate. It is evidenced that LVO layers are made of two orientational variants of a distorted perovskite compatible with bulk LaVO3, while SVO layers suffers from a tetragonal distortion due to the substrate-induced stain. Electron energy loss spectroscopy investigations indicate changes in the fine structure of the V L23 edge, related to a valence change between the LaVO3 and the SrVO3 layers. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000288160300006 |
Publication Date |
2011-03-09 |
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 |
26 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:88648UA @ admin @ c:irua:88648 |
Serial |
2054 |
Permanent link to this record |
|
|
|
Author |
Martens, J.A.; Thybaut, J.W.; Denayer, J.F.M.; Sree, S.P.; Aerts, A.; Reyniers, M.-F.; van Speybroeck, V.; Waroquier, M.; Buekenhoudt, A.; Vankelecom, I.; Buijs, W.; Persoons, J.; Baron, G.V.; Bals, S.; Van Tendeloo, G.; Marin, G.B.; Jacobs, P.A.; Kirschhock, C.E.A. |
Title |
Catalytic and molecular separation properties of Zeogrids and Zeotiles |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Catalysis today |
Abbreviated Journal |
Catal Today |
Volume |
168 |
Issue |
1 |
Pages |
17-27 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Zeogrids and Zeotiles are hierarchical materials built from assembled MFI zeolite precursor units. Permanent secondary porosity in these materials is obtained through self assembly of nanoparticles encountered in MFI zeolite synthesis in the presence of supramolecular templates. Hereon, the aggregated species are termed nanoslabs. Zeogrids are layered materials with lateral spacings between nanoslabs creating galleries qualifying as supermicropores. Zeotiles present a diversity of tridimensional nanoslab assemblies with mesopores. Zeotile-1, -4 and -6 are hexagonal mesostructures. Zeotile-1 has triangular and hexagonal channels; Zeotile-4 has hexagonal channels interconnected via slits. Zeotile-2 has a cubic structure with gyroid type mesoporosity. The behavior of Zeogrids and Zeotiles in adsorption, membrane and chromatographic separation and catalysis has been characterized and compared with zeolites and mesoporous materials derived from unstructured silica sources. Shape selectivity was detected via adsorption of n- and iso-alkanes. The mesoporosity of Zeotiles can be exploited in chromatographic separation of biomolecules. Zeotiles present attractive separation properties relevant to CO2 sequestration. Because of its facile synthesis procedure without hydrothermal steps Zeogrid is convenient for membrane synthesis. The performance of Zeogrid membrane in gas separation, nanofiltration and pervaporation is reported. In the Beckmann rearrangement of cyclohexanone oxime Zeogrids and Zeotiles display a catalytic activity characteristic of silicalite-1 zeolites. Introduction of acidity and redox catalytic activity can be achieved via incorporation of Al and Ti atoms in the nanoslabs during synthesis. Zeogrids are active in hydrocracking, catalytic cracking, alkylation and epoxidation reactions. Zeogrids and Zeotiles often behave differently from ordered mesoporous materials as well as from zeolites and present a valuable extension of the family of hierarchical silicate based materials. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000291033300003 |
Publication Date |
2011-03-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0920-5861; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.636 |
Times cited |
13 |
Open Access |
|
Notes |
Fwo; Iap
Sbo |
Approved |
Most recent IF: 4.636; 2011 IF: 3.407 |
Call Number |
UA @ lucian @ c:irua:88647 |
Serial |
290 |
Permanent link to this record |
|
|
|
Author |
Müller, M.; Turner, S.; Lebedev, O.I.; Wang, Y.; Van Tendeloo, G.; Fischer, R.A. |
Title |
Au@MOF-5 and Au/Mox@MOF-5 (M = Zn, Ti; x = 1, 2) : preparation and microstructural characterisation |
Type |
A1 Journal article |
Year |
2011 |
Publication |
European journal of inorganic chemistry |
Abbreviated Journal |
Eur J Inorg Chem |
Volume |
|
Issue |
12 |
Pages |
1876-1887 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The Zn-carboxylate-based porous coordination polymer MOF-5 [Zn4O(bdc)3] and the metal oxide loaded materials ZnO@MOF-5 and TiO2@MOF-5 were loaded in a second step with the precursor [ClAuCO] to yield intermediate materials denoted as [ClAuCO]@MOF-5, [ClAuCO]/ZnO@MOF-5 and [ClAuCO]/TiO2@MOF-5. These composites were decomposed to Au@MOF-5, Au/ZnO@MOF-5 and Au/TiO2@MOF-5 under hydrogen at 100 °C. The nanoparticle-loaded hybrid materials were characterised by powder X-ray diffraction (PXRD), IR spectroscopy, X-ray photoelectron spectroscopy (XPS) and N2 sorption measurements, which reveal an intact MOF-5 structure that maintains a high specific surface area. For Au@MOF-5, crystalline Au nanoparticles were distributed over the MOF matrix in a homogeneous fashion with a size of ca. 13 nm, evidenced by high resolution transmission electron microscopy. In the case of Au/ZnO@MOF-5, the Au and metal oxide particles of a few nm in size were coexistent in a given volume of the MOF-5 matrix and were not separated in different crystalline MOF particles. For the TiO2 loaded materials the oxide is preferentially located near the outer surface of the MOF particles, leading to an increase of larger exterior Au particles in comparison to very small interior Au particles as observed for the other materials. Au@MOF-5, Au/ZnO@MOF-5 and Au/TiO2@MOF-5 were tested in liquid-phase oxidation of alcohols. Preliminary results show a high activity for the Au loaded materials in this reaction. This observation is attributed to the microstructure of the composites with very small Au particles distributed homogeneously over the MOF matrix. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000289644300004 |
Publication Date |
2011-03-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-1948; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.444 |
Times cited |
75 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.444; 2011 IF: 3.049 |
Call Number |
UA @ lucian @ c:irua:88644 |
Serial |
205 |
Permanent link to this record |
|
|
|
Author |
Zhang, L.; Vleugels, J.; Darchuk, L.; van der Biest, O. |
Title |
Magnetic field oriented tetragonal zirconia with anisotropic toughness |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of the European Ceramic Society |
Abbreviated Journal |
|
Volume |
31 |
Issue |
8 |
Pages |
1405-1412 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
(0 0 1)-oriented 3 mol% yttria stabilized tetragonal zirconia (3Y-TZP) has been developed by reactive synthesis of undoped pure monoclinic zirconia and co-precipitated 8 mol% yttria-stabilized zirconia (8Y-ZrO2). The dispersed pure monoclinic ZrO2 powder, having magnetic anisotropy, was first aligned in a strong magnetic field and co-sintered in a randomly distributed cubic 8Y-ZrO2 fine matrix powder. The reactive sintering resulted in a 3Y-TZP ceramic with a (0 0 1) orientation. The (0 0 1)-oriented 3Y-TZP showed a substantial toughness anisotropy, i.e. the toughness along the [0 0 1] direction is 54% higher than that of its perpendicular direction. Moreover, the toughness along the [0 0 1] direction is 49% higher than that of a non-textured isotropic reactively synthesized 3Y-TZP and 110% higher than that of an isotropic co-precipitated powder based 3Y-TZP. The substantially enhanced toughness was interpreted in terms of the tetragonal to monoclinic martensitic phase transformability. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000290189100008 |
Publication Date |
2011-03-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0955-2219 |
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:89722 |
Serial |
8192 |
Permanent link to this record |
|
|
|
Author |
Carvalho, J.C.N.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M. |
Title |
Yukawa particles confined in a channel and subject to a periodic potential : ground state and normal modes |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
9 |
Pages |
094109-094109,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We consider a classical system of two-dimensional (2D) charged particles, interacting through a repulsive Yukawa potential exp(-r/λ)/r, and confined in a parabolic channel that limits the motion of the particles in the y direction. Along the x direction, the particles are subject to a periodic potential. The ground-state configurations and the normal-mode spectra of the system are obtained as a function of the periodicity and strength of the periodic potential (V0) and density. An interesting set of tunable ground-state configurations are found, with first- or second-order structural transitions between them. A configuration with particles aligned, perpendicular to the x direction, in each minimum of the periodic potential is obtained for V0 larger than some critical value that has a power-law dependence on the density. The phonon spectrum of different configurations was also calculated. A localization of the modes into a small frequency interval is observed for sufficiently large strength of the periodic potential, and a tunable gap in the phonon spectrum is found as a function of V0. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000288119700001 |
Publication Date |
2011-03-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
Notes |
; This work was supported by the Brazilian agencies CNPq and FUNCAP (PRONEX-Grant), and the bilateral projects between Flanders and Brazil and the Flemish Science Foundation (FWO-VI) and CNPq. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:88779 |
Serial |
3928 |
Permanent link to this record |
|
|
|
Author |
Goris, B.; Bals, S.; van den Broek, W.; Verbeeck, J.; Van Tendeloo, G. |
Title |
Exploring different inelastic projection mechanisms for electron tomography |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
111 |
Issue |
8 |
Pages |
1262-1267 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Several different projection mechanisms that all make use of inelastically scattered electrons are used for electron tomography. The advantages and the disadvantages of these methods are compared to HAADFSTEM tomography, which is considered as the standard electron tomography technique in materials science. The different inelastic setups used are energy filtered transmission electron microscopy (EFTEM), thickness mapping based on the log-ratio method and bulk plasmon mapping. We present a comparison that can be used to select the best inelastic signal for tomography, depending on different parameters such as the beam stability and nature of the sample. The appropriate signal will obviously also depend on the exact information which is requested. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000300461100039 |
Publication Date |
2011-03-07 |
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 |
21 |
Open Access |
|
Notes |
Fwo; Iap; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
Call Number |
UA @ lucian @ c:irua:91260UA @ admin @ c:irua:91260 |
Serial |
1151 |
Permanent link to this record |
|
|
|
Author |
Rouchon, V.; Duranton, M.; Burgaud, C.; Pellizzi, E.; Lavédrine, B.; Janssens, K.; de Nolf, W.; Nuyts, G.; Vanmeert, F.; Hellemans, K. |
Title |
Room-temperature study of iron gall ink impregnated paper degradation under various oxygen and humidity conditions : time-dependent monitoring by viscosity and X-ray absorption near-edge spectrometry measurements |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
83 |
Issue |
7 |
Pages |
2589-2597 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Many western manuscripts were written using iron gall inks. These inks can damage the paper via two major mechanisms: (a) acid hydrolysis, enhanced by humidity, and (b) oxidative depolymerization provoked by the presence of oxygen and free iron(II) ions. The degradation of unsized Whatman paper impregnated with different combinations of iron sulfate, gallic acid, and gum arabic was studied at room temperature in order to assess the relative importance of each mechanism. The samples were stored in various environments including a dry and/or an oxygen-free atmosphere. The cellulose depolymerization was monitored by viscometry and related to changes in the oxidation state of iron, determined by X-ray absorption near-edge spectrometry. The results indicate that residual amounts of oxygen (less than 0.1%) promote cellulose depolymerization, whereas the level of relative humidity has no impact. The cellulose depolymerization also appears closely correlated to oxidative mechanisms. Regarding the oxidation of iron, it only occurs in the simultaneous presence of oxygen and moisture, suggesting the occurrence of rustlike oxidative mechanisms. Finally, the presence of gallic acid has a strong influence, which is only partially explained by its capacity to reduce iron(III) to iron(II). |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000288887700028 |
Publication Date |
2011-03-04 |
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 |
28 |
Open Access |
|
Notes |
; This research was supported by the French Ministry of Culture within the National Program of Research (“La conservation des manuscrits: etude du vieillissement naturel de papiers impregnes d'encres ferrogalliques”). It was funded by grants from HASYLAB (experiments I-20090280 EC and II-20060245 EC) and SOLEIL (proposals 20060396 and 20080761) and was supported by the Interuniversity Attraction Poles Programme Belgian Science Policy (1UAP V1/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects nos. G.0689.06, G.0704.08 and G017909N. We are thankful to Dr. Dominique Thaudiere, Dr. Solenn Reguer, Dr. Andrea Somogyi, Dr. Karen Appel, Dr. Manuela Borchert, and Dr. Gerald Falkenberg for their assistance and help during the experiments performed at SOLEIL beamline “DIFFABS” and at HASYLAB Beam line “L” respectively. ; |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
Call Number |
UA @ admin @ c:irua:89593 |
Serial |
5822 |
Permanent link to this record |
|
|
|
Author |
Hao, Y.L.; Djotyan, A.P.; Avetisyan, A.A.; Peeters, F.M. |
Title |
D- shallow donor near a semiconductor-metal and a semiconductor-dielectric interface |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
23 |
Issue |
11 |
Pages |
115303,1-115313,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The ground state energy and the extent of the wavefunction of a negatively charged donor (D − ) located near a semiconductormetal or a semiconductordielectric interface are obtained. We apply the effective mass approximation and use a variational two-electron wavefunction that takes into account the influence of all image charges that arise due to the presence of the interface, as well as the correlation between the two electrons bound to the donor. For a semiconductormetal interface, the D − binding energy is enhanced for donor positions d > 1.5aB (aB is the effective Bohr radius) due to the additional attraction of the electrons with their images. When the donor approaches the interface (i.e. d < 1.5aB) the D − binding energy drops and eventually it becomes unbound. For a semiconductordielectric (or a semiconductorvacuum) interface the D − binding energy is reduced for any donor position as compared to the bulk case and the system becomes rapidly unbound when the donor approaches the interface. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000287969200013 |
Publication Date |
2011-03-04 |
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 |
5 |
Open Access |
|
Notes |
; This work was supported by the Belgian Science Policy (IAP) and the Brazilian Science Foundation CNPq. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (IAP). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
Call Number |
UA @ lucian @ c:irua:88828 |
Serial |
3528 |
Permanent link to this record |
|
|
|
Author |
Katti, G.; Stucchi, M.; Velenis, D.; Sorée, B.; de Meyer, K.; Dehaene, W. |
Title |
Temperature-dependent modeling and characterization of through-silicon via capacitance |
Type |
A1 Journal article |
Year |
2011 |
Publication |
IEEE electron device letters |
Abbreviated Journal |
Ieee Electr Device L |
Volume |
32 |
Issue |
4 |
Pages |
563-565 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A semianalytical model of the through-silicon via (TSV) capacitance for elevated operating temperatures is derived and verified with electrical measurements. The effect of temperature on the increase in TSV capacitance over different technology parameters is explored, and it is shown that higher oxide thickness reduces the impact of temperature rise on TSV capacitance, while with low doped substrates, which are instrumental for reducing the TSV capacitance, the sensitivity of TSV capacitance to temperature is large and cannot be ignored. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000288664800045 |
Publication Date |
2011-03-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0741-3106;1558-0563; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.048 |
Times cited |
27 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.048; 2011 IF: 2.849 |
Call Number |
UA @ lucian @ c:irua:89402 |
Serial |
3498 |
Permanent link to this record |
|
|
|
Author |
Radepont, M.; de Nolf, W.; Janssens, K.; van der Snickt, G.; Coquinot, Y.; Klaassen, L.; Cotte, M. |
Title |
The use of microscopic X-ray diffraction for the study of HgS and its degradation products corderoite (\alpha-Hg3S2Cl2), kenhsuite (\gamma-Hg3S2Cl2) and calomel (Hg2Cl2) in historical paintings |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
Volume |
26 |
Issue |
5 |
Pages |
959-968 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Since antiquity, the red pigment mercury sulfide (α-HgS), called cinnabar in its natural form or vermilion red when synthetic, was very often used in frescoes and paintings, even if it was known to suffer occasionally from degradation. The paint hereby acquires a black or silver-grey aspect. The chemical characterization of these alteration products is rather challenging mainly because of the micrometric size and heterogeneity of the surface layers that develop and that are responsible for the color change. Methods such as electron microscopy, synchrotron-based microscopic X-ray fluorescence, microscopic X-ray absorption near edge spectroscopy, Raman microscopy and secondary ion microscopy have been previously employed to identify the (Hg- and S-) compounds present and to study their co-localization. Next to these, also microscopic X-ray diffraction (XRD) (either by making use of laboratory X-ray sources or when used at a synchrotron facility) allows the identification of the crystal phases that are present in degraded HgS paint layers. In this paper we employ these various forms of micro-XRD to analyze degraded red paint in different paintings and compare the results with other X-ray based methods. Whereas the elemental analyses of the degradation products revealed, next to mercury and sulfur, the presence of chlorine, X-ray diffraction allowed the identification, next to α-HgS, of the Hg and S-containing compound calomel (Hg2Cl2) but also of the Hg, S and Cl-containing minerals corderoite (α-Hg3S2Cl2) and kenhsuite (γ-Hg3S2Cl2). These observations are consistent with X-ray absorption spectroscopy measurements performed at the S- and Cl-edges. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000289731900011 |
Publication Date |
2011-03-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.379 |
Times cited |
40 |
Open Access |
|
Notes |
; The authors gratefully acknowledge GOA programme “XANES meets EELS'' (University of Antwerp Research Council), the IUAP VI/P16 programme ”Nacho'' (BELSPO, Brussels, Belgium) and FWO (Brussels, Belgium) projects no. G.0689.06, G.0704.08 and G017909N for financial support, the ESRF for granting beamtime under proposals no. EC442 and EC720, and Gema Martinez-Criado for practical help on ID18F. The KMSKA staff is also gratefully acknowledged for their help and interest. Javier Chillida is thanked for providing us with the Pedralbes samples. The authors are also indebted to the CHARISMA project (grant agreement 228330) for financial support. ; |
Approved |
Most recent IF: 3.379; 2011 IF: 3.220 |
Call Number |
UA @ admin @ c:irua:89927 |
Serial |
5896 |
Permanent link to this record |
|
|
|
Author |
Neyts, E.C.; Khalilov, U.; Pourtois, G.; van Duin, A.C.T. |
Title |
Hyperthermal oxygen interacting with silicon surfaces : adsorption, implantation, and damage creation |
Type |
A1 Journal article |
Year |
2011 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
115 |
Issue |
15 |
Pages |
4818-4823 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Using reactive molecular dynamics simulations, we have investigated the effect of single-impact, low-energy (thermal-100 eV) bombardment of a Si(100){2 × 1} surface by atomic and molecular oxygen. Penetration probability distributions, as well as defect formation distributions, are presented as a function of the impact energy for both species. It is found that at low impact energy, defects are created chemically due to the chemisorption process in the top layers of the surface, while at high impact energy, additional defects are created by a knock-on displacement of Si. These results are of particular importance for understanding device performances of silica-based microelectronic and photovoltaic devices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000288401200060 |
Publication Date |
2011-03-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.536; 2011 IF: 4.805 |
Call Number |
UA @ lucian @ c:irua:89858 |
Serial |
1543 |
Permanent link to this record |
|
|
|
Author |
Jehanathan, N.; Georgieva, V.; Saraiva, M.; Depla, D.; Bogaerts, A.; Van Tendeloo, G. |
Title |
The influence of Cr and Y on the micro structural evolution of Mg―Cr―O and Mg―Y―O thin films |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
519 |
Issue |
16 |
Pages |
5388-5396 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Electron microscopy for materials research (EMAT) |
Abstract |
The compositional influence of Cr and Y on the microstructure of Mg―Cr―O, and Mg―Y―O films synthesized by reactive magnetron sputtering has been investigated by transmission electron microscopy, X-ray diffraction and molecular dynamics simulations. A decrease in crystallinity is observed in these films as the M (Cr or Y) content is increased. It is found that M forms a solid solution with MgO for metal ratios up to ~ 70% and ~ 50% for Cr and Y respectively. Above ~ 70% Cr metal ratio the Mg―Cr―O films are found to be completely amorphous. The Mg―Y―O films are composed of Mg(Y)O and Y2O3 nano crystallites, up to ~ 50% Y metal ratio. Above this ratio, only Y2O3 nano crystallites are found. The preferential < 111> MgO grain alignment is strongly affected by the increase in M content. For M metal ratios up to ~ 50%, there is a selective promotion of the < 100> MgO grain alignments and a decline in the < 111> grain alignments. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000292573500013 |
Publication Date |
2011-02-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0040-6090; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
4 |
Open Access |
|
Notes |
Iwt |
Approved |
Most recent IF: 1.879; 2011 IF: 1.890 |
Call Number |
UA @ lucian @ c:irua:89516 |
Serial |
1618 |
Permanent link to this record |
|
|
|
Author |
Chaves, A.; Peeters, F.M.; Farias, G.A.; Milošević, M.V. |
Title |
Vortex-vortex interaction in bulk superconductors : Ginzburg-Landau theory |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
5 |
Pages |
054516-054516,14 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The vortex-vortex interaction potential in bulk superconductors is calculated within the Ginzburg-Landau (GL) theory and is obtained from a numerical solution of a set of two coupled nonlinear GL differential equations for the vector potential and the superconducting order parameter, where the merger of vortices into a giant vortex is allowed. Further, the interaction potentials between a vortex and a giant vortex and between a vortex and an antivortex are obtained for both type-I and type-II superconductors. Our numerical results agree asymptotically with the analytical expressions for large intervortex separations that are available in the literature. We propose empirical expressions valid over the full interaction range, which are fitted to our numerical data for different values of the GL parameter. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000287712100009 |
Publication Date |
2011-02-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
31 |
Open Access |
|
Notes |
; Discussions with J. S. Andrade Jr. and A. A. Moreira are gratefully acknowledged. This work was financially supported by CNPq, under Contract No. NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the collaborative project CNPq-FWO-Vl, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:88805 |
Serial |
3899 |
Permanent link to this record |
|
|
|
Author |
Vansweevelt, R.; Mortet, V.; D' Haen, J.; Ruttens, bart; van Haesendonck, C.; Partoens, B.; Peeters, F.M.; Wagner, P. |
Title |
Study on the giant positive magnetoresistance and Hall effect in ultrathin graphite flakes |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
Volume |
208 |
Issue |
6 |
Pages |
1252-1258 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this paper, we report on the electronic transport properties of mesoscopic, ultrathin graphite flakes with a thickness corresponding to a stack of 150 graphene layers. The graphite flakes show an unexpectedly strong positive magnetoresistance (PMR) already at room temperature, which scales in good approximation with the square of the magnetic field. Furthermore, we show that the resistivity is unaffected by magnetic fields oriented in plane with the graphene layers. Hall effect measurements indicate that the charge carriers are p-type and their concentration increases with increasing temperature while the mobility is decreasing. The Hall voltage is non-linear in higher magnetic fields. Possible origins of the observed effects are discussed. Ball and stick model of the two topmost carbon layers of the hexagonal graphite structure. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000292945800008 |
Publication Date |
2011-02-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1862-6300; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.775 |
Times cited |
8 |
Open Access |
|
Notes |
; The authors gratefully acknowledge the support by FWO – Research Foundation Flanders (project G.0159.07 “Structural and electronic properties of biologically modified, graphene-based layers”), by the Federal Belgian Interuniversity Attraction Poles Programme BELSPO (project TAP VI P6/42 “Quantum effects in clusters and nanowires”) and by the Methusalem network “NANO – Antwerp-Hasselt,” funded by the Flemish Community. Technical assistance by Stoffel D. Janssens (magnet calibration and software development), Dr. Hong Yin (AFM-based thickness studies), Dr. Ronald Thoelen (data analysis), and Prof. Hans-Gerd Boyen (XPS spectroscopy) is greatly appreciated. ; |
Approved |
Most recent IF: 1.775; 2011 IF: 1.463 |
Call Number |
UA @ lucian @ c:irua:91941 |
Serial |
3343 |
Permanent link to this record |
|
|
|
Author |
Eckert, M.; Mortet, V.; Zhang, L.; Neyts, E.; Verbeeck, J.; Haenen, ken; Bogaerts, A. |
Title |
Theoretical investigation of grain size tuning during prolonged bias-enhanced nucleation |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
23 |
Issue |
6 |
Pages |
1414-1423 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, the effects of prolonged bias-enhanced nucleation (prolonged BEN) on the growth mechanisms of diamond are investigated by molecular dynamics (MD) and combined MD-Metropolis Monte Carlo (MD-MMC) simulations. First, cumulative impacts of CxHy+ and Hx+ on an a-C:H/nanodiamond composite were simulated; second, nonconsecutive impacts of the dominant ions were simulated in order to understand the observed phenomena in more detail. As stated in the existing literature, the growth of diamond structures during prolonged BEN is a process that takes place below the surface of the growing film. The investigation of the penetration behavior of CxHy+ and Hx+ species shows that the carbon-containing ions remain trapped within this amorphous phase where they dominate mechanisms like precipitation of sp3 carbon clusters. The H+ ions, however, penetrate into the crystalline phase at high bias voltages (>100 V), destroying the perfect diamond structure. The experimentally measured reduction of grain sizes at high bias voltage, reported in the literature, might thus be related to penetrating H+ ions. Furthermore, the CxHy+ ions are found to be the most efficient sputtering agents, preventing the build up of defective material. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000288291400011 |
Publication Date |
2011-02-23 |
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 |
9 |
Open Access |
|
Notes |
Iwt; Fwo; Esteem 026019; Iap |
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
Call Number |
UA @ lucian @ c:irua:87642 |
Serial |
3605 |
Permanent link to this record |
|
|
|
Author |
Nga, T.T.N.; Peeters, F.M. |
Title |
Influence of electron-electron interaction on the cyclotron resonance spectrum of magnetic quantum dots containing few electrons |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
7 |
Pages |
075419-075419,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The configuration interaction method is used to obtain the magneto-optical absorption spectrum of a few-electron (Ne=1,2,,5) quantum dot containing a single magnetic ion. We find that the IR spectrum (the position, the number, and the oscillator strength of the cyclotron resonance peaks) depends on the strength of the Coulomb interaction, the number of electrons, and the position of the magnetic ion. We find that the Kohn theorem is no longer valid as a consequence of the electron-spin-magnetic-ion-spin-exchange interaction. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000287584600011 |
Publication Date |
2011-02-23 |
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 |
8 |
Open Access |
|
Notes |
; This work was supported by FWO-Vl (Flemish Science Foundation), the Brazilian science foundation CNPq, and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:88912 |
Serial |
1620 |
Permanent link to this record |
|
|
|
Author |
Vernimmen, J.; Guidotti, M.; Silvestre-Albero, J.; Jardim, E.O.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Psaro, R.; Rodríguez-Reinoso, F.; Meynen, V.; Cool, P. |
Title |
Immersion calorimetry as a tool to evaluate the catalytic performance of titanosilicate materials in the epoxidation of cyclohexene |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Langmuir: the ACS journal of surfaces and colloids |
Abbreviated Journal |
Langmuir |
Volume |
27 |
Issue |
7 |
Pages |
3618-3625 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Different types of titanosilicates are synthesized, structurally characterized, and subsequently catalytically tested in the liquid-phase epoxidation of cyclohexene. The performance of three types of combined zeolitic/mesoporous materials is compared with that of widely studied Ti-grafted-MCM-41 molecular sieve and the TS-1 microporous titanosilicate. The catalytic test results are correlated with the structural characteristics of the different catalysts. Moreover, for the first time, immersion calorimetry with the same substrate molecule as in the catalytic test reaction is applied as an extra means to interpret the catalytic results. A good correlation between catalytic performance and immersion calorimetry results is found. This work points out that the combination of catalytic testing and immersion calorimetry can lead to important insights into the influence of the materials structural characteristics on catalysis. Moreover, the potential of using immersion calorimetry as a screening tool for catalysts in epoxidation reactions is shown. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000288970900054 |
Publication Date |
2011-02-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0743-7463;1520-5827; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.833 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.833; 2011 IF: 4.186 |
Call Number |
UA @ lucian @ c:irua:88366 |
Serial |
1557 |
Permanent link to this record |
|
|
|
Author |
Sels, D.; Sorée, B.; Groeseneken, G. |
Title |
Quantum ballistic transport in the junctionless nanowire pinch-off field effect transistor |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
Volume |
10 |
Issue |
1 |
Pages |
216-221 |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
Abstract |
In this work we investigate quantum ballistic transport in ultrasmall junctionless and inversion mode semiconducting nanowire transistors within the framework of the self-consistent Schrödinger-Poisson problem. The quantum transmitting boundary method is used to generate open boundary conditions between the active region and the electron reservoirs. We adopt a subband decomposition approach to make the problem numerically tractable and make a comparison of four different numerical approaches to solve the self-consistent Schrödinger-Poisson problem. Finally we discuss the IV-characteristics for small (r≤5 nm) GaAs nanowire transistors. The novel junctionless pinch-off FET or junctionless nanowire transistor is extensively compared with the gate-all-around (GAA) nanowire MOSFET. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
S.l. |
Editor |
|
Language |
|
Wos |
000300735800021 |
Publication Date |
2011-02-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1569-8025;1572-8137; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.526 |
Times cited |
12 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 1.526; 2011 IF: 1.211 |
Call Number |
UA @ lucian @ c:irua:89501 |
Serial |
2772 |
Permanent link to this record |
|
|
|
Author |
Sofo, J.O.; Suarez, A.M.; Usaj, G.; Cornaglia, P.S.; Hernández-Nieves, A.D.; Balseiro, C.A. |
Title |
Electrical control of the chemical bonding of fluorine on graphene |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
8 |
Pages |
081411 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the electronic structure of diluted F atoms chemisorbed on graphene using density functional theory calculations. We show that the nature of the chemical bonding of a F atom adsorbed on top of a C atom in graphene strongly depends on carrier doping. In neutral samples the F impurities induce a sp(3)-like bonding of the C atom below, generating a local distortion of the hexagonal lattice. As the graphene is electron-doped, the C atom retracts back to the graphene plane and for high doping (10(14) cm(-2)) its electronic structure corresponds to a nearly pure sp(2) configuration. We interpret this sp(3)-sp(2) doping-induced crossover in terms of a simple tight-binding model and discuss the physical consequences of this change. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000287484800005 |
Publication Date |
2011-02-18 |
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 |
65 |
Open Access |
|
Notes |
; J.O.S. and A. S. acknowledge support from the Donors of the American Chemical Society Petroleum Research Fund and use of facilities at the Penn State Materials Simulation Center. G. U., P. S. C., A. D. H., and C. A. B. acknowledge financial support from PICTs 06-483 and 2008-2236 from ANPCyT and PIP 11220080101821 from CONICET, Argentina. A. D. H. acknowledges support from the Flemish Science Foundation (FWO). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:105600 |
Serial |
892 |
Permanent link to this record |
|
|
|
Author |
Buysse, C.; Kovalevsky, A.; Snijkers, F.; Buekenhoudt, A.; Mullens, S.; Luyten, J.; Kretzschmar, J.; Lenaerts, S. |
Title |
Development, performance and stability of sulfur-free, macrovoid-free BSCF capillaries for high temperature oxygen separation from air |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of membrane science |
Abbreviated Journal |
J Membrane Sci |
Volume |
372 |
Issue |
1/2 |
Pages |
239-248 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Capture and storage of CO2 (CCS) from fossil-fuel power plants is vital in order to counteract a pending anthropogenic global warming. High temperature oxygen transport perovskite membranes can fulfill an important role in the separation of oxygen from air needed in the oxy-fuel technologies for CCS. In this study we present the development, performance and stability of gastight, macrovoid-free and sulfur-free Ba0.5Sr0.5Co0.8Fe0.2O3 − δ (BSCF) mixed conductor capillary membranes prepared by phase-inversion spinning and sintering. A sulfur-free phase-inversion polymer was chosen in order to obtain a phase-pure BSCF crystal phase. Special attention was given to the polymer solution and ceramic spinning suspension in order to avoid macrovoids and achieve gastight membranes. The sulfur-free BSCF capillaries showed an average 4-point bending strength of 64 ± 8 MPa and a maximum oxygen flux of not, vert, similar5.3 Nml/(cm2 min) at 950 °C for an argon sweep flow rate of 125 Nml/min. The comparison of the performance of sulfur-free and sulfur-containing BSCF capillaries with similar dimensions revealed a profound impact of the sulfur contamination on both the oxygen flux and the activation energy of the overall oxygen transport mechanism. Both long-term oxygen permeation at different temperatures and post-operation analysis of a sulfur-free BSCF capillary were performed and discussed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000289829200026 |
Publication Date |
2011-02-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0376-7388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.035 |
Times cited |
32 |
Open Access |
|
Notes |
; The authors want to express their thanks to the VITO staff for their continuous support, especially B. Molenberghs, W. Doyen, H. Beckers, R. Kemps, M. Mertens, M. Schoeters and H. Chen. C. Buysse thankfully acknowledges a PhD scholarship provided by VITO and the University of Antwerp. This work is performed in the framework of the German Helmholtz Alliance Project “MEM-BRAIN”, aiming at the development of gas separation membranes for zero-emission fossil fuel power plants. ; |
Approved |
Most recent IF: 6.035; 2011 IF: 3.850 |
Call Number |
UA @ admin @ c:irua:89916 |
Serial |
5942 |
Permanent link to this record |
|
|
|
Author |
Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B. |
Title |
Accurate pseudopotential description of the GW bandstructure of ZnO |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Computer physics communications |
Abbreviated Journal |
Comput Phys Commun |
Volume |
182 |
Issue |
9 |
Pages |
2029-2031 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
We present the GW band structure of ZnO in its wurtzite (WZ), zincblende (ZB) and rocksalt (RS) phases at the Γ point, calculated within the GW approximation. We have used a Zn20+ pseudopotential which is essential for the adequate treatment of the exchange interaction in the self-energy. The accuracy of the pseudopotential used is also discussed. The effect of the pd hybridization on the GW corrections to the band gap is correlated by comparing the ZB and RS phase. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000292675100062 |
Publication Date |
2011-02-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0010-4655; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.936 |
Times cited |
18 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.936; 2011 IF: 3.268 |
Call Number |
UA @ lucian @ c:irua:90761 |
Serial |
51 |
Permanent link to this record |
|
|
|
Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Dik, J.; Radepont, M.; Hendriks, E.; Geldof, M.; Cotte, M. |
Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 2 : original paint layer samples |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
83 |
Issue |
4 |
Pages |
1224-1231 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The darkening of the original yellow areas painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is a phenomenon widely observed on several paintings by Vincent van Gogh, such as the famous different versions of Sunflowers. During our previous investigations on artificially aged model samples of lead chromate, we established for the first time that darkening of chrome yellow is caused by reduction of PbCrO4 to Cr2O3·2H2O (viridian green), likely accompanied by the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide]. In the second part of this work, in order to demonstrate that this reduction phenomenon effectively takes place in real paintings, we study original paint samples from two paintings of V. van Gogh. As with the model samples, in view of the thin superficial alteration layers that are present, high lateral resolution spectroscopic methods that make use of synchrotron radiation (SR), such as microscopic X-ray absorption near edge (μ-XANES) and X-ray fluorescence spectrometry (μ-XRF) were employed. Additionally, μ-Raman and mid-FTIR analyses were carried out to completely characterize the samples. On both paint microsamples, the local presence of reduced Cr was demonstrated by means of μ-XANES point measurements. The presence of Cr(III) was revealed in specific areas, in some cases correlated to the presence of Ba(sulfate) and/or to that of aluminum silicate compounds. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000287176900012 |
Publication Date |
2011-02-14 |
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 |
84 |
Open Access |
|
Notes |
; This research was funded by grants from ESRF (experiment EC-504) and by HASYLAB (experiments 11-20080130 EC and 11-20070157 EC) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Van Gogh Museum, Amsterdam, is acknowledged for their agreeable cooperation and for the authorization to publish the images of the paintings in this article. L.M. was financially supported by the Erasmus Placement in the framework of Lifelong Learning Programme (A.Y. 2009-2010). The EU Community's FP7 Research Infrastructures program under the CHARISMA Project (Grant Agreement 228330) is also acknowledged. ; |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
Call Number |
UA @ admin @ c:irua:88795 |
Serial |
5571 |
Permanent link to this record |
|
|
|
Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Verbeeck, J.; Tian, H.; Tan, H.; Dik, J.; Radepont, M.; Cotte, M. |
Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
83 |
Issue |
4 |
Pages |
1214-1223 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000287176900011 |
Publication Date |
2011-02-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700;1520-6882; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
113 |
Open Access |
|
Notes |
Iuap; Fwo |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
Call Number |
UA @ lucian @ c:irua:88794UA @ admin @ c:irua:88794 |
Serial |
632 |
Permanent link to this record |
|
|
|
Author |
Lebedev, O.I.; Caignaert, V.; Raveau, B.; Pop, N.; Gozzo, F.; Van Tendeloo, G.; Pralong, V. |
Title |
HRTEM and neutron diffraction study of LixMo5O17 : from the ribbon (x=5) structure to the rock salt (x=12) structure |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
Volume |
184 |
Issue |
4 |
Pages |
790-796 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Structure determination of the fully intercalated phase Li12Mo5O17 and of the deintercalated oxide Li5Mo5O17 has been carried out by electron microscopy and neutron powder diffraction. The reversible topotactic transformation between the ordered rock salt structure of the former and the ribbon structure of the latter (closely related to that of Li4Mo5O17) is explained on the following basis: both structures can be described as strips built up as an assembly of infinite ribbons of MoO6 octahedra that are five octahedra thick, and that differ by slight displacements of the octahedral ribbons. We show that the electrochemical behavior of the LixMo5O17 system is based on two sorts of Li+ sites; those that are located within the strips between the ribbons, and those that are located at the border of the strips. The high rate of Li intercalation in this oxide and its reversibility are discussed in terms of its peculiar structure. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000289597100010 |
Publication Date |
2011-02-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.299 |
Times cited |
1 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.299; 2011 IF: 2.159 |
Call Number |
UA @ lucian @ c:irua:88646 |
Serial |
1515 |
Permanent link to this record |
|
|
|
Author |
Mao, M.; Bogaerts, A. |
Title |
Plasma chemistry modeling for an inductively coupled plasma used for the growth of carbon nanotubes |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
Volume |
275 |
Issue |
1 |
Pages |
012021,1-012021,9 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A hybrid model, called the hybrid plasma equipment model (HPEM), is used to describe the plasma chemistry in an inductively coupled plasma, operating in a gas mixture of C2H2 with either H2 or NH3, as typically used for carbon nanotube (CNT) growth. Two-dimensional profiles of power density, electron temperature and density, gas temperature, and densities of some plasma species are plotted and analyzed. Besides, the fluxes of the various plasma species towards the substrate (where the CNTs can be grown), as well as the decomposition rates of the feedstock gases (C2H2, NH3 and H2), are calculated as a function of the C2H2 fraction in both gas mixtures. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
|
Publication Date |
2011-02-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
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:85859 |
Serial |
2631 |
Permanent link to this record |
|
|
|
Author |
Verbeeck, J.; Bertoni, G.; Lichte, H. |
Title |
A holographic biprism as a perfect energy filter? |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
111 |
Issue |
7 |
Pages |
887-893 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
It has often been stated that a holographic biprism represents a near perfect energy filter and only elastically scattered electrons can participate in the interference fringes. This is based on the assumption that the reference wave does not contain inelastically scattered electrons. In this letter we show that this is not exactly true because of the delocalised inelastic interaction of the reference wave with the sample. We experimentally and theoretically show that inelastic scattering plays a role in the fringe formation, but it is shown that this contribution is small and can usually be neglected in practice. (C) 2011 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000300461000021 |
Publication Date |
2011-02-05 |
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 |
13 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
Call Number |
UA @ lucian @ c:irua:97250UA @ admin @ c:irua:97250 |
Serial |
1482 |
Permanent link to this record |