Records |
Author |
Tan, H.; Lebedev, O.I.; McLaughlin, A.C.; Van Tendeloo, G. |
Title |
The superstructure and superconductivity of Ru1222 based RuSr2Gd2-x-yYyCexCu2O10-\delta compounds |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
23 |
Issue |
11 |
Pages |
115013-115013,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
For the first time, the local structure and physical properties of Ru1222 based compounds (RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta) and RuSr(2)Gd(1.8-x)Y(0.2)CexCu(2)O(10) (x = 0.90-0.55)) have been investigated and analyzed together on the very same compounds. The Ru1222 superstructure was confirmed by TEM at a local scale and was suggested to have an orthorhombic symmetry with space group Aba2 and lattice parameters a(s) similar or equal to root 2a, b(s) similar or equal to root 2a and c(s) = c. This new Ru1222 superstructure distortion from tetragonal symmetry is proposed to have a positive correlation with the superconductivity variation of these compounds. The more the distortion towards orthorhombic symmetry, the higher the critical superconducting temperature these compounds can achieve. The T(c)(0) of RuSr(2)Gd(1.8-x)Y(0.2)Ce(x)Cu(2)O(10-delta) (x = 0.85-0.55) increases monotonically from 4 to 16 K when x decreases from 0.85 to 0.70, then RuSr(2)Gd(2)Cu(2)O(8) defects emerge and the T(c) decreases with decreasing x. Ru1212 defects are observed to intergrow epitaxially with the Ru1222 structure as lamellas along the c-axis in RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta). Although Ru1212 is a superconductor, the intergrowth severely restrains its superconductivity. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000284308000013 |
Publication Date |
2010-10-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
1 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.878; 2010 IF: 2.402 |
Call Number |
UA @ lucian @ c:irua:95553 |
Serial |
3385 |
Permanent link to this record |
|
|
|
Author |
Yang, T.; Abakumov, A.M.; Hadermann, J.; Van Tendeloo, G.; Nowik, I.; Stephens, P.W.; Hamberger, J.; Tsirlin, A.A.; Ramanujachary, K.V.; Lofland, S.; Croft, M.; Ignatov, A.; Sun, J.; Greenblatt, M. |
Title |
_BiMnFe2O6, a polysynthetically twinned hcp MO structure |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Chemical science |
Abbreviated Journal |
Chem Sci |
Volume |
1 |
Issue |
6 |
Pages |
751-762 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The most efficient use of spatial volume and the lowest potential energies in the metal oxide structures are based on cubic close packing (ccp) or hexagonal close packing (hcp) of anions with cations occupying the interstices. A promising way to tune the composition of close packed oxides and design new compounds is related to fragmenting the parent structure into modules by periodically spaced planar interfaces, such as twin planes at the unit cell scale. The unique crystal chemistry properties of cations with a lone electron pair, such as Bi3+ or Pb2+, when located at interfaces, enables them to act as chemical scissors, to help relieve configurational strain. With this approach, we synthesized a new oxide, BiMnFe2O6, where fragments of the hypothetical hcp oxygen-based MO structure (the NiAs structure type), for the first time, serve as the building modules in a complex transition metal oxide. Mn3+ and Fe3+ ions are randomly distributed in two crystallographically independent sites (M1 and M2). The structure consists of quasi two-dimensional blocks of the 2H hexagonal close packed MO structure cut along the (114) crystal plane of the hcp lattice and stacked along the c axis. The blocks are related by a mirror operation that allows BiMnFe2O6 to be considered as a polysynthetically twinned 2H hcp MO structure. The transition to an AFM state with an incommensurate spin configuration at [similar] 212 K is established by 57Fe Mössbauer spectroscopy, magnetic susceptibility, specific heat and low temperature powder neutron diffraction. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Royal Society of Chemistry |
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000283939200013 |
Publication Date |
2010-10-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-6520;2041-6539; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.668 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.668; 2010 IF: NA |
Call Number |
UA @ lucian @ c:irua:85823 |
Serial |
3517 |
Permanent link to this record |
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|
|
Author |
Barbier, M.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Single-layer and bilayer graphene superlattices: collimation, additional Dirac points and Dirac lines |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Philosophical transactions of the Royal Society : mathematical, physical and engineering sciences |
Abbreviated Journal |
Philos T R Soc A |
Volume |
368 |
Issue |
1932 |
Pages |
5499-5524 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We review the energy spectrum and transport properties of several types of one-dimensional superlattices (SLs) on single-layer and bilayer graphene. In single-layer graphene, for certain SL parameters an electron beam incident on an SL is highly collimated. On the other hand, there are extra Dirac points generated for other SL parameters. Using rectangular barriers allows us to find analytical expressions for the location of new Dirac points in the spectrum and for the renormalization of the electron velocities. The influence of these extra Dirac points on the conductivity is investigated. In the limit of δ-function barriers, the transmission T through and conductance G of a finite number of barriers as well as the energy spectra of SLs are periodic functions of the dimensionless strength P of the barriers, Graphic, with vF the Fermi velocity. For a KronigPenney SL with alternating sign of the height of the barriers, the Dirac point becomes a Dirac line for P = π/2+nπ with n an integer. In bilayer graphene, with an appropriate bias applied to the barriers and wells, we show that several new types of SLs are produced and two of them are similar to type I and type II semiconductor SLs. Similar to single-layer graphene SLs, extra Dirac points are found in bilayer graphene SLs. Non-ballistic transport is also considered. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000283660000011 |
Publication Date |
2010-11-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1364-503X;1471-2962; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.97 |
Times cited |
64 |
Open Access |
|
Notes |
; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the Canadian NSERC through grant no. OGP0121756. ; |
Approved |
Most recent IF: 2.97; 2010 IF: 2.459 |
Call Number |
UA @ lucian @ c:irua:85597 |
Serial |
3023 |
Permanent link to this record |
|
|
|
Author |
Yan, L.; Niu, H.J.; Duong, G.V.; Suchomel, M.R.; Bacsa, J.; Chalker, P.R.; Hadermann, J.; Van Tendeloo, G.; Rosseinsky, M.J. |
Title |
Cation ordering within the perovskite block of a six-layer Ruddlesden-Popper oxide from layer-by-layer growth artificial interfaces in complex unit cells |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Chemical science |
Abbreviated Journal |
Chem Sci |
Volume |
2 |
Issue |
2 |
Pages |
261-272 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The (AO)(ABO3)n Ruddlesden-Popper structure is an archetypal complex oxide consisting of two distinct structural units, an (AO) rock salt layer separating an n-octahedra thick perovskite block. Conventional high-temperature oxide synthesis methods cannot access members with n > 3, but low-temperature layer-by-layer thin film methods allow the preparation of materials with thicker perovskite blocks, exploiting high surface mobility and lattice matching with the substrate. This paper describes the growth of an n = 6 member CaO[(CSMO)2(LCMO)2 (CSMO)2] in which the six unit cell perovskite block is sub-divided into two central La0.67Ca0.33MnO3 (LCMO) and two terminal Ca0.85Sm0.15MnO3 (CSMO) layers to allow stabilization of the rock salt layer and variation of the transition metal charge. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Royal Society of Chemistry |
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000286327600010 |
Publication Date |
2010-11-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-6520;2041-6539; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.668 |
Times cited |
16 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.668; 2011 IF: 7.525 |
Call Number |
UA @ lucian @ c:irua:88652 |
Serial |
300 |
Permanent link to this record |
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|
|
Author |
Kovalevsky, A.; Buysse, C.; Snijkers, F.; Buekenhoudt, A.; Luyten, J.; Kretzschmar, J.; Lenaerts, S. |
Title |
Oxygen exchange-limited transport and surface activation of Ba0.5Sr0.5Co0.8Fe0.2O3-\delta capillary membranes |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of membrane science |
Abbreviated Journal |
J Membrane Sci |
Volume |
368 |
Issue |
1/2 |
Pages |
223-232 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Analysis of oxygen permeation fluxes through Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) capillary membranes, fabricated via a phase-inversion spinning technique using polysulfone as binder, showed a significant limiting role of the surface-oxygen exchange kinetics. Within the studied temperature and oxygen partial pressure ranges, the activation of core and shell sides of the BSCF capillary with praseodymium oxide (PrOx) resulted in an increase in permeation rate of about 300%. At 11231223 K the activated BSCF membranes demonstrate almost 3-times lower activation energies for the overall oxygen transport (not, vert, similar35 kJ/mol) than the non-activated capillaries, indicating that the mechanism of oxygen transport through the activated capillaries becomes significantly controlled by bulk diffusion limitations, allowing further improvement of the overall performance by decreasing the wall thickness. XRD, EDS and EPMA studies revealed the formation of (Pr,Ba,Sr)(Co,Fe)O3−δ perovskite-type oxides on the surface of the PrOx-modified membranes, which may be responsible for the drastic increase in oxygen exchange rate. At T > 1123 K both non-activated and activated Ba0.5Sr0.5Co0.8Fe0.2O3−δ membranes demonstrate stable performance with time, while at 1073 K only a small initial decrease in permeation was observed. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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Language |
|
Wos |
000286701800027 |
Publication Date |
2010-11-21 |
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 |
21 |
Open Access |
|
Notes |
; This work was supported by the German Helmholtz Alliance Project “MEM-BRAIN”, aiming at the development of gas separation membranes for zero-emission fossil fuel power plants. Experimental assistance of B. Molenberghs, W. Doyen, H. Chen, R. Kemps, M. Mertens, I. Thijs, and W. Bouwen (VITO) is gratefully acknowledged. ; |
Approved |
Most recent IF: 6.035; 2011 IF: 3.850 |
Call Number |
UA @ admin @ c:irua:88072 |
Serial |
5975 |
Permanent link to this record |
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|
Author |
Tian, H.; Schryvers, D.; Claeys, P. |
Title |
Nanodiamonds do not provide unique evidence for a Younger Dryas impact |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Proceedings of the National Academy of Sciences of the United States of America |
Abbreviated Journal |
P Natl Acad Sci Usa |
Volume |
108 |
Issue |
1 |
Pages |
40-44 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Microstructural, δ13C isotope and C/N ratio investigations were conducted on excavated material from the black Younger Dryas boundary in Lommel, Belgium, aiming for a characterisation of the carbon content and structures. Cubic diamond nanoparticles are found in large numbers. The larger ones with diameters around or above 10 nm often exhibit single or multiple twins. The smaller ones around 5 nm in diameter are mostly defect-free. Also larger flake-like particles, around 100 nm in lateral dimension, with a cubic diamond structure are observed as well as large carbon onion structures. The combination of these characteristics does not yield unique evidence for an exogenic impact related to the investigated layer. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000285915000012 |
Publication Date |
2010-12-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0027-8424;1091-6490; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.661 |
Times cited |
32 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.661; 2011 IF: 9.681 |
Call Number |
UA @ lucian @ c:irua:88733 |
Serial |
2254 |
Permanent link to this record |
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|
Author |
Vanhumbeeck, J.-F.; Tian, H.; Schryvers, D.; Proost, J. |
Title |
Stress-assisted crystallisation in anodic titania |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Corrosion science |
Abbreviated Journal |
Corros Sci |
Volume |
53 |
Issue |
4 |
Pages |
1269-1277 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The relationship between the microstructural and internal stress evolution during Ti anodising is discussed. Samples anodised galvanostatically to 12 V and 40 V, corresponding to different stages of the internal stress evolution, were examined by in-plane and cross-section transmission electron microscopy. Electron diffraction patterns have been complemented with stoichiometry data obtained from energy loss near edge structure spectra. The sample anodised to 40 V was observed to consist of two regions, with a crystallised inner region adjacent to the metal/oxide interface. Crystallisation of this region is associated with the presence of large compressive internal stresses which build up during anodising up to 12 V. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000288972000016 |
Publication Date |
2010-12-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0010-938X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.245 |
Times cited |
11 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 5.245; 2011 IF: 3.734 |
Call Number |
UA @ lucian @ c:irua:88385 |
Serial |
3177 |
Permanent link to this record |
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|
Author |
Verleysen, E.; Bender, H.; Richard, O.; Schryvers, D.; Vandervorst, W. |
Title |
Compositional characterization of nickel silicides by HAADF-STEM imaging |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of materials science |
Abbreviated Journal |
J Mater Sci |
Volume |
46 |
Issue |
7 |
Pages |
2001-2008 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A methodology for the quantitative compositional characterization of nickel silicides by high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) imaging is presented. HAADF-STEM images of a set of nickel silicide reference samples Ni3Si, Ni31Si12, Ni2Si, NiSi and NiSi2 are taken at identical experimental conditions. The correlation between sample thickness and HAADF-STEM intensity is discussed. In order to quantify the relationship between the experimental Z-contrast intensities and the composition of the analysed layers, the ratio of the HAADF-STEM intensity to the sample thickness or to the intensity of the silicon substrate is determined for each nickel silicide reference sample. Diffraction contrast is still detected on the HAADF-STEM images, even though the detector is set at the largest possible detection angle. The influence on the quantification results of intensity fluctuations caused by diffraction contrast and channelling is examined. The methodology is applied to FUSI gate devices and to horizontal TFET devices with different nickel silicides formed on source, gate and drain. It is shown that, if the elements which are present are known, this methodology allows a fast quantitative 2-dimensional compositional analysis. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
|
Wos |
000286633000002 |
Publication Date |
2011-01-06 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-2461;1573-4803; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.599 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.599; 2011 IF: 2.015 |
Call Number |
UA @ lucian @ c:irua:88950 |
Serial |
446 |
Permanent link to this record |
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|
|
Author |
Tinck, S.; Bogaerts, A. |
Title |
Computer simulations of an oxygen inductively coupled plasma used for plasma-assisted atomic layer deposition |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
1 |
Pages |
015008-015008,10 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, an O2 inductively coupled plasma used for plasma enhanced atomic layer deposition of Al2O3 thin films is investigated by means of modeling. This work intends to provide more information about basic plasma properties such as species densities and species fluxes to the substrate as a function of power and pressure, which might be hard to measure experimentally. For this purpose, a hybrid model developed by Kushner et al is applied to calculate the plasma characteristics in the reactor volume for different chamber pressures ranging from 1 to 10 mTorr and different coil powers ranging from 50 to 500 W. Density profiles of the various oxygen containing plasma species are reported as well as fluxes to the substrate under various operating conditions. Furthermore, different orientations of the substrate, which can be placed vertically or horizontally in the reactor, are taken into account. In addition, special attention is paid to the recombination process of atomic oxygen on the different reactor walls under the stated operating conditions. From this work it can be concluded that the plasma properties change significantly in different locations of the reactor. The plasma density near the cylindrical coil is high, while it is almost negligible in the neighborhood of the substrate. Ion and excited species fluxes to the substrate are found to be very low and negligible. Finally, the orientation of the substrate has a minor effect on the flux of O2, while it has a significant effect on the flux of O. In the horizontal configuration, the flux of atomic oxygen can be up to one order of magnitude lower than in the vertical configuration. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000286592200009 |
Publication Date |
2011-01-08 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:85285 |
Serial |
467 |
Permanent link to this record |
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|
|
Author |
Verberck, B. |
Title |
Symmetry-adapted rotator functions for molecules in cylindrical confinement |
Type |
A1 Journal article |
Year |
2011 |
Publication |
International journal of molecular sciences |
Abbreviated Journal |
Int J Mol Sci |
Volume |
12 |
Issue |
1 |
Pages |
317-333 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present a general description of the formalism of symmetry-adapted rotator functions (SARFs) for molecules in cylindrical confinement. Molecules are considered as clusters of interaction centers (ICs), can have any symmetry, and can display different types of ICs. Cylindrical confinement can be realized by encapsulation in a carbon nanotube (CNT). The potential energy of a molecule surrounded by a CNT can be calculated by evaluating a limited number of terms of an expansion into SARFs, which offers a significant reduction of the computation time. Optimal molecular orientations can be deduced from the resulting potential energy landscape. Examples, including the case of a molecule with cubic symmetry inside a CNT, are discussed. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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Language |
|
Wos |
000286583400017 |
Publication Date |
2011-01-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1422-0067; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.226 |
Times cited |
1 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.226; 2011 IF: NA |
Call Number |
UA @ lucian @ c:irua:88048 |
Serial |
3402 |
Permanent link to this record |
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|
Author |
Kapra, A.V.; Misko, V.R.; Vodolazov, D.Y.; Peeters, F.M. |
Title |
The guidance of vortex-antivortex pairs by in-plane magnetic dipoles in a superconducting finite-size film |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
24 |
Issue |
2 |
Pages |
024014-024014,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The possibility of manipulating vortex matter by using various artificial pinning arrays is of significant importance for possible applications in nano and micro fluxonics devices. By numerically solving the time-dependent GinzburgLandau equations, we study the vortexantivortex (vav) dynamics in a hybrid structure consisting of a finite-size superconductor with magnetic dipoles on top which generate vav pairs in the presence of an external current. The vav dynamics is analyzed for different arrangements and magnetic moments of the dipoles, as a function of angle α between the direction of the magnetic dipole and that of the Lorentz force produced by the applied current. The interplay of the attractive interaction between a vav pair and the Lorentz force leads either to the separation of (anti)vortices and their motion in opposite directions or to their annihilation. We found a critical angle αc, below which vortices and antivortices are repelled, while for larger angles they annihilate. In case of a single (few) magnetic dipole(s), this magnetic dipole induced vav guidance is influenced by the self-interaction of the vav pairs with their images in a finite-size sample, while for a periodic array of dipoles the guidance is determined by the interaction of a vav pair with other dipoles and vav pairs created by them. This effect is tunable through the external current and the magnetization and size of the magnetic dipoles. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000286379900015 |
Publication Date |
2011-01-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
28 |
Open Access |
|
Notes |
; This work was supported by the 'Odysseus' program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, and the FWO-Vl. DYV acknowledges support from the Russian Fund for Basic Research and Russian Agency of Education under the Federal Programme 'Scientific and educational personnel of innovative Russia in 2009-2013'. ; |
Approved |
Most recent IF: 2.878; 2011 IF: 2.662 |
Call Number |
UA @ lucian @ c:irua:88732 |
Serial |
1399 |
Permanent link to this record |
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|
|
Author |
Milošević, M.V.; Peeters, F.M.; Jankó, B. |
Title |
Vortex manipulation in superconducting films with tunable magnetic topology |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
24 |
Issue |
2 |
Pages |
024001-024001,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using a combination of the phenomenological GinzburgLandau theory and micromagnetic simulations, we study properties of a superconducting film with an array of soft magnetic dots on top. An external in-plane magnetic field gradually drives the magnets from an out-of-plane or magnetic vortex state to an in-plane single-domain state, which changes spatially the distribution of the superconducting condensate. If induced by the magnets, the vortexantivortex molecules exhibit rich transitions as a function of the applied in-plane field. At the same time, we show how the magnetic dots act as very effective dynamic pinning centers for vortices in an applied perpendicular magnetic field. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000286379900002 |
Publication Date |
2011-01-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
8 |
Open Access |
|
Notes |
; This research was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the JSPS/ESF-NES program, the bilateral project between Flanders and the USA, NSF NIRT, ECS-0609249, and the Institute for Theoretical Sciences. ; |
Approved |
Most recent IF: 2.878; 2011 IF: 2.662 |
Call Number |
UA @ lucian @ c:irua:88731 |
Serial |
3870 |
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 |
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 |
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|
|
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 |
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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 |
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|
Author |
De Bie, C.; Martens, T.; van Dijk, J.; Paulussen, S.; Verheyde, B.; Corthals, S.; Bogaerts, A. |
Title |
Dielectric barrier discharges used for the conversion of greenhouse gases: modeling the plasma chemistry by fluid simulations |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
2 |
Pages |
024008,1-024008,11 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The conversion of methane to value-added chemicals and fuels is considered to be one of the challenges of the 21st century. In this paper we study, by means of fluid modeling, the conversion of methane to higher hydrocarbons or oxygenates by partial oxidation with CO2 or O2 in a dielectric barrier discharge. Sixty-nine different plasma species (electrons, ions, molecules, radicals) are included in the model, as well as a comprehensive set of chemical reactions. The calculation results presented in this paper include the conversion of the reactants and the yields of the reaction products as a function of residence time in the reactor, for different gas mixing ratios. Syngas (i.e. H2 + CO) and higher hydrocarbons (C2Hx) are typically found to be important reaction products. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000290719900009 |
Publication Date |
2011-04-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
38 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:87868 |
Serial |
689 |
Permanent link to this record |
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Author |
Molina, L.; Tan, H.; Biermans, E.; Batenburg, K.J.; Verbeeck, J.; Bals, S.; Van Tendeloo, G. |
Title |
Barrier efficiency of sponge-like La2Zr2O7 buffer layers for YBCO-coated conductors |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
24 |
Issue |
6 |
Pages |
065019-065019,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Solution derived La2Zr2O7 films have drawn much attention for potential applications as thermal barriers or low-cost buffer layers for coated conductor technology. Annealing and coating parameters strongly affect the microstructure of La2Zr2O7, but different film processing methods can yield similar microstructural features such as nanovoids and nanometer-sized La2Zr2O7 grains. Nanoporosity is a typical feature found in such films and the implications for the functionality of the films are investigated by a combination of scanning transmission electron microscopy (STEM), electron energy-loss spectroscopy (EELS) and quantitative electron tomography. Chemical solution based La2Zr2O7 films deposited on flexible Ni5 at.%W substrates with a {100}lang001rang biaxial texture were prepared for an in-depth characterization. A sponge-like structure composed of nanometer-sized voids is revealed by high-angle annular dark-field scanning transmission electron microscopy in combination with electron tomography. A three-dimensional quantification of nanovoids in the La2Zr2O7 film is obtained on a local scale. Mostly non-interconnected highly faceted nanovoids compromise more than one-fifth of the investigated sample volume. The diffusion barrier efficiency of a 170 nm thick La2Zr2O7 film is investigated by STEM-EELS, yielding a 1.8 ± 0.2 nm oxide layer beyond which no significant nickel diffusion can be detected and intermixing is observed. This is of particular significance for the functionality of YBa2Cu3O7 − δ coated conductor architectures based on solution derived La2Zr2O7 films as diffusion barriers. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000290472900021 |
Publication Date |
2011-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
31 |
Open Access |
|
Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 2.878; 2011 IF: 2.662 |
Call Number |
UA @ lucian @ c:irua:88639UA @ admin @ c:irua:88639 |
Serial |
221 |
Permanent link to this record |
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|
Author |
Meulebroeck, W.; Cosyns, P.; Baert, K.; Wouters, H.; Cagno, S.; Janssens, K.; Terryn, H.; Nys, K.; Thienpont, H. |
Title |
Optical spectroscopy as a rapid and low-cost tool for the first-line analysis of glass artefacts : a step-by-step plan for Roman green glass |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of archaeological science |
Abbreviated Journal |
J Archaeol Sci |
Volume |
38 |
Issue |
9 |
Pages |
2387-2398 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Archaeometric research on glass artefacts is continuously evolving and is converging towards a multidisciplinary research domain where different types of techniques are applied depending on the questions asked and the circumstances involved. The technique described in this work is optical spectroscopy. The benefit of this technique being the possibility of building up a knowledge database for a large amount of material in a relatively short period of time and with a relatively limited budget. This is of particular interest for the investigation of extensive and/or unexplored glass collections where a first-line analysis of artefacts could facilitate the selection of material needing further and more detailed examination. This publication explores the extent to which optical spectroscopy can be used for a first-line analysis of green coloured glass artefacts from the Roman period. It is shown that the colour coordinates calculated from the measured transmission spectrum could reveal information about the fragment under study. In particular it is shown that 1) based on the position of the calculated colour values on the colour diagram (CIE1931) one could easily know whether the artefact was coloured using only iron or if copper oxides were also present. In the case of the artefact owing its colour solely to the presence of iron, the distance between the measured colour values and the colour diagrams white point can roughly indicate the iron concentration of the sample; 2) artefacts that were fabricated under similar furnace conditions can also be identified on the colour diagram; 3) samples with identical compositions and fabrication conditions but with different sample thickness, gave rise to a variation in the colour coordinates, thus allowing optical spectroscopy to help identify fragments which might belong to the same object. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000293551200037 |
Publication Date |
2011-05-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0305-4403 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.602 |
Times cited |
18 |
Open Access |
|
Notes |
; The authors would like to express their gratitude to the Vrije Universiteit Brussel for funding this research in the framework of HOA15, a “Horizontal Research Action” which encourages collaboration between research groups from different departments within the same University having expertise in specific research disciplines and also to the OZR-project 1247 BOF. The authors are also very grateful to the following persons for having permitted the study of their material: Rica Annaert and Sofie Vanhoutte of the “Vlaams lnstituut voor Onroerend Erfgoed (VIOE): Grobbendonk, Matagne-la-Petite, Oudenburg; Jean-Louis Antoine of the Musee Archeologique Namur: Nismes; Tom Debruyne of the ”Erfgoedcel“ Tienen: Tienen: Marc Rogge and Kurt Braeckman of the ”Provinciaal Archeologisch Museum (PAM)": Kruishoutem, Velzeke; Walter Sevenants: Rumst and Anne de Pyre-Gysel from the Musee Romain d'Avenches: Avenches. ; |
Approved |
Most recent IF: 2.602; 2011 IF: 1.914 |
Call Number |
UA @ admin @ c:irua:92389 |
Serial |
5756 |
Permanent link to this record |
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Author |
Bultinck, E.; Bogaerts, A. |
Title |
Characterization of an Ar/O2 magnetron plasma by a multi-species Monte Carlo model |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
4 |
Pages |
045013-045013,12 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A combined Monte Carlo (MC)/analytical surface model is developed to study the plasma processes occurring during the reactive sputter deposition of TiOx thin films. This model describes the important plasma species with a MC approach (i.e. electrons, Ar+ ions, {\rm O}_2 |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000295829800015 |
Publication Date |
2011-06-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:89732 |
Serial |
316 |
Permanent link to this record |
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|
|
Author |
Tinck, S.; Boullart, W.; Bogaerts, A. |
Title |
Modeling Cl2/O2/Ar inductively coupled plasmas used for silicon etching : effects of SiO2 chamber wall coating |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
4 |
Pages |
045012-045012,19 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, simulations are performed to gain a better insight into the properties of a Cl2/Ar plasma, with and without O2, during plasma etching of Si. Both plasma and surface properties are calculated in a self-consistent manner. Special attention is paid to the behavior of etch products coming from the wafer or the walls, and how the chamber walls can affect the plasma and the resulting etch process. Two modeling cases are considered. In the first case, the reactor walls are defined as clean (Al2O3), whereas in the second case a SiO2 coating is introduced on the reactor walls before the etching process, so that oxygen will be sputtered from the walls and introduced into the plasma. For this reason, a detailed reaction set is presented for a Cl2/O2/Ar plasma containing etched species, as well as an extensive reaction set for surface processes, including physical and chemical sputtering, chemical etching and deposition processes. Density and flux profiles of various species are presented for a better understanding of the bulk plasma during the etching process. Detailed information is also given on the composition of the surfaces at various locations of the reactor, on the etch products in the plasma and on the surface loss probabilities of the plasma species at the walls, with different compositions. It is found that in the clean chamber, walls are mostly chlorinated (Al2Cl3), with a thin layer of etch products residing on the wall. In the coated chamber, an oxy-chloride layer is grown on the walls for a few nanometers during the etching process. The Cl atom wall loss probability is found to decrease significantly in the coated chamber, hence increasing the etch rate. SiCl2, SiCl4 and SiCl3 are found to be the main etch products in the plasma, with the fraction of SiCl2 being always slightly higher. The simulation results compare well with experimental data available from the literature. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000295829800014 |
Publication Date |
2011-06-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
22 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:91045 |
Serial |
2141 |
Permanent link to this record |
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Author |
Nikolova, I.; Janssen, S.; Vrancken, K.; Vos, P.; Mishra, V.; Berghmans, P. |
Title |
Size resolved ultrafine particles emission model : a continues size distribution approach |
Type |
A1 Journal article |
Year |
2011 |
Publication |
The science of the total environment |
Abbreviated Journal |
|
Volume |
409 |
Issue |
18 |
Pages |
3492-3499 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
A new parameterization for size resolved ultrafine particles (UFP) traffic emissions is proposed based on the results of PARTICULATES project (Samaras et al., 2005). It includes the emission factors from the Emission Inventory Guidebook (2006) (total number of particles, #/km/veh), the shape of the corresponding particle size distribution given in PARTICULATES and data for the traffic activity. The output of the model UFPEM (UltraFine Particle Emission Model) is a sum of continuous distributions of ultrafine particles emissions per vehicle type (passenger cars and heavy duty vehicles), fuel (petrol and diesel) and average speed representative for urban, rural and highway driving. The results from the parameterization are compared with measured total number of ultrafine particles and size distributions in a tunnel in Antwerp (Belgium). The measured UFP concentration over the entire campaign shows a close relation to the traffic activity. The modelled concentration is found to be lower than the measured in the campaign. The average emission factor from the measurement is 4.29E + 14 #/km/veh whereas the calculated is around 30% lower. A comparison of emission factors with literature is done as well and in overall a good agreement is found. For the size distributions it is found that the measured distributions consist of three modes Nucleation, Aitken and accumulation and most of the ultrafine particles belong to the Nucleation and the Aitken modes. The modelled Aitken mode (peak around 0.040.05 μm) is found in a good agreement both as amplitude of the peak and the number of particles whereas the modelled Nucleation mode is shifted to smaller diameters and the peak is much lower that the observed. Time scale analysis shows that at 300 m in the tunnel coagulation and deposition are slow and therefore neglected. The UFPEM emission model can be used as a source term in dispersion models. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000293260100026 |
Publication Date |
2011-06-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0048-9697; 1879-1026 |
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:91949 |
Serial |
8546 |
Permanent link to this record |
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|
|
Author |
Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. |
Title |
Stability and structures of the CFCC-TmC phases : a first-principles study |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Computational materials science |
Abbreviated Journal |
Comp Mater Sci |
Volume |
51 |
Issue |
1 |
Pages |
146-150 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The η-M6C, γ-M23C6, and π-M11C2 phases (M = Cr, Mn and Fe) have complex cubic lattices with lattice parameters of approximately 1.0 nm. They belong to the CFCC-TmC family (complex face-centered cubic transition metal carbides), display a rich variety of crystal structures, and play in important role in iron alloys and steels. Here we show that first-principles calculations predict high stability for the γ-M23C6 and η-M6C phases, and instability for the π-M11C2 phases, taking into account various compositional and structural possibilities. The calculations also show a wide variety in magnetic properties. The Cr-containing phases were found to be non-magnetic and the Fe-phases to be ferromagnetic, while the Mn-containing phases were found to be either ferrimagnetic or non-magnetic. Details of the local atomic structures, and the formation and stability of these precipitates in alloys are discussed. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000296214300020 |
Publication Date |
2011-08-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-0256; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.292 |
Times cited |
18 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.292; 2012 IF: 1.878 |
Call Number |
UA @ lucian @ c:irua:93277 |
Serial |
3119 |
Permanent link to this record |
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|
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Author |
Orlinskii, S.B.; Bogomolov, R.S.; Kiyamova, A.M.; Yavkin, B.V.; Mamin, G.M.; Turner, S.; Van Tendeloo, G.; Shiryaev, A.A.; Vlasov, I.I.; Shenderova, O. |
Title |
Identification of substitutional nitrogen and surface paramagnetic centers in nanodiamond of dynamic synthesis by electron paramagnetic resonance |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Nanoscience and nanotechnology letters |
Abbreviated Journal |
Nanosci Nanotech Let |
Volume |
3 |
Issue |
1 |
Pages |
63-67 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Production of nanodiamond particles containing substitutional nitrogen is important for a wide variety of advanced applications. In the current work nanodiamond particles synthesized from a mixture of graphite and hexogen were analyzed to determine the presence of substitutional nitrogen using pulsed electron paramagnetic resonance (EPR) spectroscopy. Nitrogen paramagnetic centers in the amount of 1.2 ppm have been identified. The spin relaxation characteristics for both nitrogen and surface defects are also reported. A new approach for efficient depletion of the strong non-nitrogen EPR signal in nanodiamond material by immersing nanodiamond particles into ice matrix is suggested. This approach allows an essential decrease of the spin relaxation time of the dominant non-nitrogen defects, while preserving the substitutional nitrogen spin relaxation time. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000293211200012 |
Publication Date |
2011-09-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1941-4900;1941-4919; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.889 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.889; 2011 IF: 0.528 |
Call Number |
UA @ lucian @ c:irua:91943 |
Serial |
1548 |
Permanent link to this record |
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Author |
Oprya, M.; Kiro, S.; Worobiec, A.; Horemans, B.; Darchuk, L.; Novakovic, V.; Ennan, A.; Van Grieken, R. |
Title |
Size distribution and chemical properties of welding fumes of inhalable particles |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of aerosol science |
Abbreviated Journal |
|
Volume |
45 |
Issue |
1 |
Pages |
50-57 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) |
Abstract |
The goal of the present study was to analyze the relationship between the fume formation rate, welding conditions, chemical composition of welding fume particles and their size. In the range from 0.25 to 16 μm aerodynamic diameter, three distinct types of welding fume particles were identified in the welder's breathing zone. The elemental composition of each type depended completely on the used welding materials, and reflects their mechanism of formation. Their relative abundance in the welding fume appeared to be dependent on the electrode coating, as well as the heat input during welding. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000300140000005 |
Publication Date |
2011-10-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8502; 1879-1964 |
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:93184 |
Serial |
8544 |
Permanent link to this record |
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Author |
Nikolova, I.; Janssen, S.; Vos, P.; Vrancken, K.; Mishra, V.; Berghmans, P. |
Title |
Dispersion modelling of traffic induced ultrafine particles in a street canyon in Antwerp, Belgium and comparison with observations |
Type |
A1 Journal article |
Year |
2011 |
Publication |
The science of the total environment |
Abbreviated Journal |
|
Volume |
412 |
Issue |
|
Pages |
336-343 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The aim of this study is to investigate the dispersion of ultrafine particles and its spatial distribution in a street canyon and its neighbourhood with the 3D CFD model ENVI-met®. The performance of the model at street scale is evaluated and the importance of the boundary conditions like wind field and traffic emissions on the UFP concentration is demonstrated. To support and validate the modelled results, a short-term measurement campaign was conducted in a street canyon in Antwerp, Belgium. The UFP concentration was measured simultaneously with P-TRACK (TSI Model 8525) at four different locations in the canyon. The modelled UFP concentrations compare well with the measured data (correlation coefficient R from 0.44 to 0.93) within the standard deviation of the measurements. Despite the moderate traffic flow in the street canyon, UFP concentrations in the canyon are in general double of the background concentrations, indicating the high local contribution for this particle number concentration. Some of the observed concentration profiles are not resembled by the model simulations. For these specific anomalies, further analysis is performed and plausible explanations are put forward. The role of wind direction and traffic emissions is investigated. The performance evaluation of ENVI-met® shows that in general the model qualitatively and quantitatively describes the dispersion of UFP in the street canyon study. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000298534300038 |
Publication Date |
2011-10-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0048-9697; 1879-1026 |
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:94377 |
Serial |
7815 |
Permanent link to this record |
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Author |
Denneulin, T.; Rouvière, J.L.; Béché, A.; Py, M.; Barnes, J.P.; Rochat, N.; Hartmann, J.M.; Cooper, D. |
Title |
The reduction of the substitutional C content in annealed Si/SiGeC superlattices studied by dark-field electron holography |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Semiconductor science and technology |
Abbreviated Journal |
Semicond Sci Tech |
Volume |
26 |
Issue |
12 |
Pages |
1-10 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Si/Si(1 − x − y)GexCy superlattices are used in the construction of new microelectronic architectures such as multichannel transistors. The introduction of carbon in SiGe allows for compensation of the strain and to avoid plastic relaxation. However, the formation of incoherent β-SiC clusters during annealing limits the processability of SiGeC. This precipitation leads to a modification of the strain in the alloy due to the reduction of the substitutional carbon content. Here, we investigated the strain in annealed Si/Si0.744Ge0.244C0.012 superlattices grown by reduced pressure chemical vapour deposition using dark-field electron holography. The variation of the substitutional C content was calculated by correlating the results with finite-element simulations. The obtained values were then compared with Fourier-transformed infrared spectrometry measurements. It was shown that after annealing for 2 min at 1050 °C carbon no longer has any influence on strain in the superlattice, which behaves like pure SiGe. However, a significant proportion of substitutional C atoms remain in a third-nearest neighbour (3nn) configuration. It was deduced that the influence of 3nn C on strain is negligible and that only isolated atoms have a significant contribution. It was also proposed that the 3nn configuration is an intermediary step during the formation of SiC clusters. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000300151300010 |
Publication Date |
2011-11-07 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0268-1242 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.305 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.305; 2011 IF: 1.723 |
Call Number |
UA @ lucian @ c:irua:136427 |
Serial |
4508 |
Permanent link to this record |
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Author |
Jalabert, D.; Pelloux-Gervais, D.; Béché, A.; Hartmann, J.M.; Gergaud, P.; Rouvière, J.L.; Canut, B. |
Title |
Depth strain profile with sub-nm resolution in a thin silicon film using medium energy ion scattering |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physica Status Solidi A-Applications And Materials Science |
Abbreviated Journal |
Phys Status Solidi A |
Volume |
209 |
Issue |
2 |
Pages |
265-267 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The depth strain profile in silicon from the Si (001) substrate to the surface of a 2 nm thick Si/12 nm thick SiGe/bulk Si heterostructure has been determined by medium energy ion scattering (MEIS). It shows with sub-nanometer resolution and high strain sensitivity that the thin Si cap presents residual compressive strain caused by Ge diffusion coming from the fully strained SiGe layer underneath. The strain state of the SiGe buffer have been checked by X-ray diffraction (XRD) and nano-beam electron diffraction (NBED) measurements. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000303382700005 |
Publication Date |
2011-11-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1862-6300; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.775 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.775; 2012 IF: 1.469 |
Call Number |
UA @ lucian @ c:irua:136430 |
Serial |
4497 |
Permanent link to this record |
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Author |
Bertrand, L.; Robinet, L.; Thoury, M.; Janssens, K.; Cohen, S.X.; Schöder, S. |
Title |
Cultural heritage and archaeology materials studied by synchrotron spectroscopy and imaging |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
Appl Phys A-Mater |
Volume |
106 |
Issue |
2 |
Pages |
377-396 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The use of synchrotron radiation techniques to study cultural heritage and archaeological materials has undergone a steep increase over the past 10-15 years. The range of materials studied is very broad and encompasses painting materials, stone, glass, ceramics, metals, cellulosic and wooden materials, and a cluster of organic-based materials, in phase with the diversity observed at archaeological sites, museums, historical buildings, etc. Main areas of investigation are: (1) the study of the alteration and corrosion processes, for which the unique non-destructive speciation capabilities of X-ray absorption have proved very beneficial, (2) the understanding of the technologies and identification of the raw materials used to produce archaeological artefacts and art objects and, to a lesser extent, (3) the investigation of current or novel stabilisation, conservation and restoration practices. In terms of the synchrotron methods used, the main focus so far has been on X-ray techniques, primarily X-ray fluorescence, absorption and diffraction, and Fourier-transform infrared spectroscopy. We review here the use of these techniques from recent works published in the field demonstrating the breadth of applications and future potential offered by third generation synchrotron techniques. New developments in imaging and advanced spectroscopy, included in the UV/visible and IR ranges, could even broaden the variety of materials studied, in particular by fostering more studies on organic and complex organic-inorganic mixtures, while new support activities at synchrotron facilities might facilitate transfer of knowledge between synchrotron specialists and users from archaeology and cultural heritage sciences. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000299749000009 |
Publication Date |
2011-11-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0947-8396 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.455 |
Times cited |
55 |
Open Access |
|
Notes |
; The authors acknowledge the critical reading by B. Berrie (National Gallery of Art, Washington DC, USA). We thank J. Mass (Conservation Department, Winterthur Museum and Country Estate, Winterthur, DE, USA), H. Roemich (Institute of Fine Arts, New York University, USA), J. Hiller (Non-Crystalline Diffraction Beamline, Diamond Light Source, Didcot, UK) and J.-P. Echard (Laboratoire de recherche et de restauration, Musee de la musique, Paris, France) for their comments on the presentation of their work in the manuscript. The IPANEMA platform is jointly developed by CNRS, MNHN, the French Ministry of Culture and Communication and SOLEIL, and benefits from a CPER grant (MESR, Region Ile-de-France). Support by the Access to Research Infrastructures activity in the 7th Framework Programme of the EU (CHARISMA Grant Agreement n. 228330) and the NWO Science4Arts programme are acknowledged. ; |
Approved |
Most recent IF: 1.455; 2012 IF: 1.545 |
Call Number |
UA @ admin @ c:irua:99166 |
Serial |
5561 |
Permanent link to this record |
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Author |
Delabie, A.; Sioncke, S.; Rip, J.; Van Elshocht, S.; Pourtois, G.; Mueller, M.; Beckhoff, B.; Pierloot, K. |
Title |
Reaction mechanisms for atomic layer deposition of aluminum oxide on semiconductor substrates |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of vacuum science and technology: A: vacuum surfaces and films |
Abbreviated Journal |
J Vac Sci Technol A |
Volume |
30 |
Issue |
1 |
Pages |
01a127-01a127,10 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this work, we have studied the TMA/H(2)O (TMA Al(CH(3))(3)) atomic layer deposition (ALD) of Al(2)O(3) on hydroxyl (OH) and thiol (SH) terminated semiconductor substrates. Total reflection x-ray fluorescence reveals a complex growth-per-cycle evolution during the early ALD reaction cycles. OH and SH terminated surfaces demonstrate growth inhibition from the second reaction cycle on. Theoretical calculations, based on density functional theory, are performed on cluster models to investigate the first TMA/H(2)O reaction cycle. Based on the theoretical results, we discuss possible mechanisms for the growth inhibition from the second reaction cycle on. In addition, our calculations show that AlCH(3) groups are hydrolyzed by a H(2)O molecule adsorbed on a neighboring Al atom, independent of the type of backbonds (Si-O, Ge-O, or Ge-S) of AlCH(3). The coordination of Al remains four-fold after the first TMA/H(2)O reaction cycle. (C) 2012 American Vacuum Society. [DOI: 10.1116/1.3664090] |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000298992800027 |
Publication Date |
2011-12-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0734-2101; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.374 |
Times cited |
41 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.374; 2012 IF: 1.432 |
Call Number |
UA @ lucian @ c:irua:96253 |
Serial |
2818 |
Permanent link to this record |
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Author |
Bouvier, S.; Benmhenni, N.; Tirry, W.; Gregory, F.; Nixon, M.E.; Cazacu, O.; Rabet, L. |
Title |
Hardening in relation with microstructure evolution of high purity \alpha-titanium deformed under monotonic and cyclic simple shear loadings at room temperature |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Materials science and engineering: part A: structural materials: properties, microstructure and processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
Volume |
535 |
Issue |
|
Pages |
12-21 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The aim of this paper is to gain understanding of the quasi-static, large strain deformation behavior at room-temperature of high-purity alpha-Ti with an initial split-basal texture. Simple shear tests were conducted along different directions in order to quantify the material's anisotropy and hardening evolution for different strain paths such as monotonic, Bauschinger, and cyclic loadings. The stress-strain curves indicate that the material displays strong anisotropy in the flow behavior. In order to capture the link between microstructure evolution (occurrence of twinning, grain size evolution, etc.) and the macroscopic response, a thoroughly detailed multi-scale characterization using scanning electron microscope (SEM) observations and electron backscattered diffraction (EBSD) analysis was also conducted. Specifically, EBSD analyses indicate that the twin activity and grain fragmentation are responsible for the observed difference between the macroscopic hardening rates corresponding to different directions and loading paths. (C) 2011 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000301402400003 |
Publication Date |
2011-12-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-5093; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.094 |
Times cited |
22 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.094; 2012 IF: 2.108 |
Call Number |
UA @ lucian @ c:irua:97824 |
Serial |
1410 |
Permanent link to this record |