| |
Records |
Links |
|
Author |
Xu, B.; Milošević, M.V.; Lin, S.-H.; Peeters, F.M.; Jankó, B. |
|
| |
Title |
Formation of multiple-flux-quantum vortices in mesoscopic superconductors from simulations of calorimetric, magnetic, and transport properties |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
|
| |
Volume |
107 |
Issue |
5 |
Pages |
057002,1-057002,4 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Because of strong flux confinement in mesoscopic superconductors, a giant vortex may appear in the ground state of the system in an applied magnetic field. This multiquanta vortex can then split into individual vortices (and vice versa) as a function of, e.g., applied current, magnetic field, or temperature. Here we show that such transitions can be identified by calorimetry, as the formation or splitting of a giant vortex results in a clear jump in measured heat capacity versus external drive. We attribute this phenomenon to an abrupt change in the density of states of the quasiparticle excitations in the vortex core(s), and further link it to a sharp change of the magnetic susceptibility at the transitionproving that the formation of a giant vortex can also be detected by magnetometry. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
| |
Language |
|
Wos |
000293333100006 |
Publication Date |
2011-07-29 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links  |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
8.462 |
Times cited |
26 |
Open Access |
|
|
| |
Notes |
; We thank O. Bourgeois, T. Yokoyama, M. Eschrig, and M. Ichioka for discussions. This work was supported by FWO-Vlaanderen, the Belgian Science Policy (IAP), the bilateral project Flanders-USA, NSF NIRT, ECS-0609249, and Institute of Theoretical Sciences, Notre Dame. ; |
Approved |
Most recent IF: 8.462; 2011 IF: 7.370 |
|
| |
Call Number |
UA @ lucian @ c:irua:91237 |
Serial |
1263 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
|
| |
Title |
Graphene in inhomogeneous magnetic fields : bound, quasi-bound and scattering states |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
23 |
Issue |
31 |
Pages |
315301,1-315301,14 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
The electron states in graphene-based magnetic dot and magnetic ring structures and combinations of both are investigated. The corresponding spectra are studied as a function of the radii, the strengths of the inhomogeneous magnetic field and of a uniform background field, the strength of an electrostatic barrier and the angular momentum quantum number. In the absence of an external magnetic field we have only long-lived quasi-bound and scattering states and we assess their influence on the density of states. In addition, we consider elastic electron scattering by a magnetic dot, whose average B vanishes, and show that the Hall and longitudinal resistivities, as a function of the Fermi energy, exhibit a pronounced oscillatory structure due to the presence of quasi-bound states. Depending on the dot parameters this oscillatory structure differs substantially for energies below and above the first Landau level. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
London |
Editor |
|
|
| |
Language |
|
Wos |
000293008900002 |
Publication Date |
2011-07-16 |
|
| |
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 |
38 |
Open Access |
|
|
| |
Notes |
; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE, the Canadian NSERC grant no. OGP0121756 and the Belgian Science Policy (IAP). We acknowledge discussions and correspondence with Professor A Matulis. ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
|
| |
Call Number |
UA @ lucian @ c:irua:91176 |
Serial |
1372 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
King, G.; Abakumov, A.M.; Woodward, P.M.; Llobet, A.; Tsirlin, A.A.; Batuk, D.; Antipov, E.V. |
|
| |
Title |
The high-temperature polymorphs of K3AlF6 |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
|
| |
Volume |
50 |
Issue |
16 |
Pages |
7792-7801 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The crystal structures of the three high-temperature polymorphs of K3AlF6 have been solved from neutron powder diffraction, synchrotron X-ray powder diffraction, and electron diffraction data. The β-phase (stable between 132 and 153 °C) and γ-phase (stable between 153 to 306 °C) can be described as unusually complex superstructures of the double-perovskite structure (K2KAlF6) which result from noncooperative tilting of the AlF6 octahedra. The β-phase is tetragonal, space group I4/m, with lattice parameters of a = 13.3862(5) Å and c = 8.5617(3) Å (at 143 °C) and Z = 10. In this phase, one-fifth of the AlF6 octahedra are rotated about the c-axis by 45° while the other four-fifths remain untilted. The large 45° rotations result in edge sharing between these AlF6 octahedra and the neighboring K-centered polyhedra, resulting in pentagonal bipyramidal coordination for four-fifths of the K+ ions that reside on the B-sites of the perovskite structure. The remaining one-fifth of the K+ ions on the B-sites retain octahedral coordination. The γ-phase is orthorhombic, space group Fddd, with lattice parameters of a = 36.1276(4) Å, b = 17.1133(2) Å, and c = 12.0562(1) Å (at 225 °C) and Z = 48. In the γ-phase, one-sixth of the AlF6 octahedra are randomly rotated about one of two directions by 45° while the other five-sixths remain essentially untilted. These rotations result in two-thirds of the K+ ions on the B-site obtaining 7-fold coordination while the other one-third remain in octahedral coordination. The δ-phase adopts the ideal cubic double-perovskite structure, space group Fmm, with a = 8.5943(1) Å at 400 °C. However, pair distribution function analysis shows that locally the δ-phase is quite different from its long-range average crystal structure. The AlF6 octahedra undergo large-amplitude rotations which are accompanied by off-center displacements of the K+ ions that occupy the 12-coordinate A-sites. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
|
| |
Language |
|
Wos |
000293493100052 |
Publication Date |
2011-07-11 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.857 |
Times cited |
19 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 4.857; 2011 IF: 4.601 |
|
| |
Call Number |
UA @ lucian @ c:irua:91131 |
Serial |
1468 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Düking, R.; Gielis, J.; Liese, W. |
|
| |
Title |
Carbon flux and carbon stock in a bamboo stand and their relevance for mitigating climate change |
Type |
A3 Journal article |
| |
Year |
2011 |
Publication |
Bamboo Science & Culture |
Abbreviated Journal |
|
|
| |
Volume |
24 |
Issue |
1 |
Pages |
1-6 |
|
| |
Keywords |
A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
|
| |
Abstract |
In this report we describe the basics of biological carbon fixation in bamboo forests. Confusing carbon stock with carbon flux has led to false expectations on the significance of bamboo forests as carbon sinks. Furthermore, misunderstandings about the growth of bamboo culms can lead to highly exaggerated expectations on the productivity of bamboo. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1535-7635 |
ISBN |
|
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:91091 |
Serial |
7578 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Caratelli, D.; Gielis, J.; Ricci, P.E. |
|
| |
Title |
Fourier-like solution of the Dirichlet problem for the Laplace Equation in k-type Gielis domains |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of pure and applied mathematics : advances and applications |
Abbreviated Journal |
|
|
| |
Volume |
5 |
Issue |
2 |
Pages |
99-111 |
|
| |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
|
| |
Abstract |
The interior and exterior Dirichlet problems for the Laplace equation in k-type Gielis domains are analytically addressed by using a suitable Fourier-like technique. A dedicated numerical procedure based on the computer-aided algebra tool Mathematica© is developed in order to validate the proposed approach. In this way, highly accurate approximations of the solution, featuring properties similar to the classical ones, are obtained. Computed results are found to be in good agreement with theoretical findings on Fourier series expansion presented by Carleson. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:91090 |
Serial |
7982 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Caratelli, D.; Gielis, J.; Natalini, P.; Ricci, P.E.; Tavkhelidze, I. |
|
| |
Title |
The Robin problem for the Helmholtz equation in a starlike planar domain |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Georgian mathematical journal |
Abbreviated Journal |
|
|
| |
Volume |
18 |
Issue |
3 |
Pages |
465-479 |
|
| |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
|
| |
Abstract |
The interior and exterior Robin problems for the Helmholtz equation in starlike planar domains are addressed by using a suitable Fourier-like technique. Attention is in particular focused on normal-polar domains whose boundaries are defined by the so-called superformula introduced by J. Gielis. A dedicated numerical procedure based on the computer algebra system Mathematica© is developed in order to validate the proposed approach. In this way, highly accurate approximations of the solution, featuring properties similar to the classical ones, are obtained. The computed results are found to be in good agreement with the theoretical findings on Fourier series expansion presented by L. Carleson. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000296166100004 |
Publication Date |
2021-02-28 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1072-947x |
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:91086 |
Serial |
8658 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Worobiec, A.; Potgieter-Vermaak, S.S.; Berghmans, P.; Winkler, H.; Burger, R.; Van Grieken, R. |
|
| |
Title |
Air particulate emissions in developing countries : a case study in South Africa |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Analytical letters |
Abbreviated Journal |
|
|
| |
Volume |
44 |
Issue |
11 |
Pages |
1907-1924 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) |
|
| |
Abstract |
Atmospheric aerosols were collected during the winter in Bethlehem, South Africa. The particulate mass concentrations, ambient carbon mass concentrations, and chemical composition of various particulate fractions showed that the area is highly polluted. The fine particle mass concentrations peaked at 1000 µg/m3 for PM2.5. Ambient carbon mass concentrations ranged from 20 to 40 µg/m3. Single particle analysis confirmed that the fine particle fraction was dominated by organic particles. The topographical conditions, causing a low inversion, together with the high amounts of emissions from biomass burning, result in unacceptable levels of air pollution and pose a considerable health threat to the population. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000294602300006 |
Publication Date |
2011-08-12 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2719 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:91079 |
Serial |
7429 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Kontozova-Deutsch, V.; Deutsch, F.; Godoi, R.H.M.; Van Grieken, R.; De Wael, K. |
|
| |
Title |
Urban air pollutants and their micro effects on medieval stained glass windows |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
|
| |
Volume |
99 |
Issue |
2 |
Pages |
508-513 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Levels of urban gaseous and particulate pollutants were investigated in the Cathedral of Cologne, Germany in the framework of the EU-project VIDRIO. The purpose of this study was to evaluate the influence of a protective double glazing system on the preservation of ancient stained glass windows by sampling at protected and unprotected windows (indoors, in the interspace and outdoor of the Cathedral). The interspace between the ancient stained glass window and the protective glazing is flushed in the Cathedral by indoor air, hence isolating the historic glass from the outdoor air and exposing it to indoor air on both sides of the glass panels. Concentrations of aggressive gaseous pollutants such as NO2, SO2, O3 and CO2 as well as elemental concentrations of bulk particles and relative abundances of single particles were surveyed at all sampling locations. Elemental concentrations in bulk particulate matter were found to be significantly lower inside the Cathedral in comparison to the outdoor air. This result is advantageous for the stained glass windows. Single particle analysis of the samples from Cologne showed also soil dust and organic particles as well as sulphates and nitrates, from which the latter two compounds are dangerous for the stained glass windows. On the base of the obtained results, it can be concluded that the protective glazing system in the Cathedral of Cologne can be considered as predominantly advantageous from both the gases' point of view (except for NO2-candles burning) and from the particles' point of view. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000295770700053 |
Publication Date |
2011-07-23 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.034 |
Times cited |
6 |
Open Access |
|
|
| |
Notes |
; This research was supported by the European Commission through the “VIDRIO-project”, contract no. EVK4-CT-2001-00045. Financial support is gratefully acknowledged. The authors acknowledge the assistance and advice during the experimental work given by the Dombauhutte team in Cologne, especially by Dr. Ulrike Brinkman and Gunter Hettinger. ; |
Approved |
Most recent IF: 3.034; 2011 IF: 3.048 |
|
| |
Call Number |
UA @ admin @ c:irua:91078 |
Serial |
5889 |
|
| Permanent link to this record |
| |
|
| |
|
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 |
|
|
| |
Corporate Author |
|
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 |
| |
|
| |
|
Author |
Hezareh, T.; Razavi, F.S.; Kremer, R.K.; Habermeier, H.-U.; Lebedev, O.I.; Kirilenko, D.; Van Tendeloo, G. |
|
| |
Title |
Effect of PbZr0.52Ti0.48O3 thin layer on structure, electronic and magnetic properties of La0.65Sr0.35MnO3 and La0.65Ca0.30MnO3 thin-films |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
| |
Volume |
109 |
Issue |
11 |
Pages |
113707,1-113707,8 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Epitaxial thin film heterostructures of high dielectric PbZr<sub>1-x</sub>Ti<sub>x</sub>O<sub>3</sub> (PZT) and La<sub>1-x</sub>A<sub>x</sub>MnO<sub>3</sub> (A-divalent alkaline earth metals such as Sr (LSMO) and Ca (LCMO)) were grown on SrTiO<sub>3</sub> substrates and their structure, temperature dependence of electrical resistivity, and magnetization were investigated as a function of the thickness of the LSMO(LCMO) layer. The microstructures of the samples were analyzed by TEM. By applying an electric field across the PZT layer, we applied a ferrodistortive pressure on the manganite layer and studied the correlations between lattice distortion and electric transport and magnetic properties of the CMR materials. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
| |
Language |
|
Wos |
000292214700069 |
Publication Date |
2011-06-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.068 |
Times cited |
4 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.068; 2011 IF: 2.168 |
|
| |
Call Number |
UA @ lucian @ c:irua:90964 |
Serial |
843 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Engbarth, M.A.; Bending, S.J.; Milošević, M.V. |
|
| |
Title |
Geometry-driven vortex states in type-I superconducting Pb nanowires |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
83 |
Issue |
22 |
Pages |
224504-224504,7 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Hall probe magnetometry has been used to investigate the magnetization of individual cylindrically shaped Pb nanowires grown by electrocrystallization on a highly oriented pyrolytic graphite electrode. These measurements have been interpreted by comparison with three-dimensional Ginzburg-Landau (GL) calculations for nanowires with our sample parameters. We find that the measured superheating field and the critical field for surface superconductivity are strongly influenced by the temperature-dependent coherence length, ξ(T) and penetration depth λ(T) and their relationship to the nanowire diameter. As the temperature is increased toward Tc this drives a change in the superconductor-normal transition from first order irreversible to first order reversible and finally second order reversible. We find that the geometrical flux confinement in our type-I nanowires leads to the formation of a one-dimensional row of single-quantum vortices. While GL calculations show a quite uniform distribution of vortices in thin nanowires, clear vortex bunching is found as the diameter increases, suggesting a transition to a more classical type-I behavior. Subtle changes in minor magnetization loops also indicate that slightly different flux configurations can form with the same vorticity, which depend on the sample history. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000291888300012 |
Publication Date |
2011-06-21 |
|
| |
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 |
19 |
Open Access |
|
|
| |
Notes |
; We acknowledge valuable conversations with F. V. Kusmartsev and W. M. Wu at Loughborough University, UK. This work was supported by the EPSRC-UK under Grant No. EP/E039944/1, and the Flemish Science Foundation (FWO). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
|
| |
Call Number |
UA @ lucian @ c:irua:90927 |
Serial |
1331 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Tinck, S.; Bogaerts, A.; Shamiryan, D. |
|
| |
Title |
Simultaneous etching and deposition processes during the etching of silicon with a Cl2/O2/Ar inductively coupled plasma |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Plasma processes and polymers |
Abbreviated Journal |
Plasma Process Polym |
|
| |
Volume |
8 |
Issue |
6 |
Pages |
490-499 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
In this article, surface processes occurring during the etching of Si with a Cl2/O2/Ar plasma are investigated by means of experiments and modeling. Cl2-based plasmas are commonly used to etch silicon, while a small fraction of O2 is added to protect the sidewalls from lateral etching during the shallow trench isolation process. When the oxygen fraction exceeds a critical value, the wafer surface process changes from an etching regime to a deposition regime, drastically reducing the etch rate. This effect is commonly referred to as the etch stop phenomenon. To gain better understanding of this mechanism, the oxygen fraction is varied in the gas mixture and special attention is paid to the effects of oxygen and of the redeposition of non-volatile etched species on the overall etch/deposition process. It is found that, when the O2 flow is increased, the etch process changes from successful etching to the formation of a rough surface, and eventually to the actual growth of an oxide layer which completely blocks the etching of the underlying Si. The size of this etch stop island was found to increase as a function of oxygen flow, while its thickness was dependent on the amount of Si etched. This suggests that the growth of the oxide layer mainly depends on the redeposition of non-volatile etch products. The abrupt change in the etch rate as a function of oxygen fraction was not found back in the oxygen content of the plasma, suggesting the competitive nature between oxidation and chlorination at the wafer. Finally, the wafer and reactor wall compositions were investigated by modeling and it was found that the surface rapidly consisted mainly of SiO2 when the O2 flow was increased above about 15 sccm. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
|
| |
Language |
|
Wos |
000292116800003 |
Publication Date |
2011-03-29 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1612-8850; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.846 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.846; 2011 IF: 2.468 |
|
| |
Call Number |
UA @ lucian @ c:irua:90926 |
Serial |
3014 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Vodolazov, D.Y.; Peeters, F.M. |
|
| |
Title |
Heating of quasiparticles driven by oscillations of the order parameter in short superconducting microbridges |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
83 |
Issue |
22 |
Pages |
224523-224523,6 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We predict heating of quasiparticles driven by order parameter oscillations in the resistive state of short superconducting microbridges. The finite relaxation time of the magnitude of the order parameter |Δ| and the dependence of the spectral functions both on |Δ| and the supervelocity Q are the origin of this effect. Our results are opposite to those of Aslamazov and Larkin [ Zh. Eks. Teor. Fiz. 70 1340 (1976)] and Schmid et al. [ Phys. Rev. B 21 5076 (1980)] where cooling of quasiparticles was found. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000292218200010 |
Publication Date |
2011-06-29 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
4 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Russian Foundation for Basic Research, Russian Agency of Education under the Federal Target Programme “Scientific and educational personnel of innovative Russia in 2009-2013,” Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
|
| |
Call Number |
UA @ lucian @ c:irua:90924 |
Serial |
1415 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Nowak, M.P.; Szafran, B.; Peeters, F.M.; Partoens, B.; Pasek, W.J. |
|
| |
Title |
Tuning of the spin-orbit interaction in a quantum dot by an in-plane magnetic field |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
83 |
Issue |
24 |
Pages |
245324-245324,12 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Using an exact-diagonalization approach we show that one- and two-electron InAs quantum dots exhibit an avoided crossing in the energy spectra that is induced by the spin-orbit coupling in the presence of an in-plane external magnetic field. The width of the avoided crossings depends strongly on the orientation of the magnetic field, which reveals the intrinsic anisotropy of the spin-orbit-coupling interactions. We find that for specific orientations of the magnetic field avoided crossings vanish. A value of this orientation can be used to extract the ratio of the strength of Rashba and Dresselhaus interactions. The spin-orbit anisotropy effects for various geometries and orientations of the confinement potential are discussed. Our analysis explains the physics behind the recent measurements performed on a gated self-assembled quantum dot [ S. Takahashi et al. Phys. Rev. Lett. 104 246801 (2010)]. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000292254000005 |
Publication Date |
2011-06-30 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
27 |
Open Access |
|
|
| |
Notes |
; The authors thank S. Takahashi for helpful discussions. This work was supported by the “Krakow Interdisciplinary PhD Project in Nanoscience and Advanced Nanostructures” operated within the Foundation for Polish Science MPD Programme co-financed by the EU European Regional Development Fund, the Project No. N N202103938 supported by the Ministry of Science an Higher Education (MNiSW) for 2010-2013, and the Belgian Science Policy (IAP). W. J. P. has been partially supported by the EU Human Capital Operation Program, Polish Project No. POKL.04.0101-00-434/08-00. Calculations were performed in ACK-CYFRONET-AGH on the RackServer Zeus. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
|
| |
Call Number |
UA @ lucian @ c:irua:90923 |
Serial |
3755 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Chaves, A.; Komendová, L.; Milošević, M.V.; Andrade, J.S.; Farias, G.A.; Peeters, F.M. |
|
| |
Title |
Conditions for nonmonotonic vortex interaction in two-band superconductors |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
83 |
Issue |
21 |
Pages |
214523-214523,6 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We describe a semianalytic approach to the two-band Ginzburg-Landau theory, which predicts the behavior of vortices in two-band superconductors. We show that the character of the short-range vortex-vortex interaction is determined by the sign of the normal domain-superconductor interface energy, in analogy with the conventional differentiation between type I and type II superconductors. However, we also show that the long-range interaction is determined by a modified Ginzburg-Landau parameter κ*, different from the standard κ of a bulk superconductor. This opens the possibility for nonmonotonic vortex-vortex interaction, which is temperature dependent, and can be further tuned by alterations of the material on the microscopic scale. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000292252300009 |
Publication Date |
2011-06-30 |
|
| |
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 |
46 |
Open Access |
|
|
| |
Notes |
; Discussions with A. Moreira, A. Shanenko, R. Prozorov, and A. Golubov are gratefully acknowledged. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the bilateral project FWO-CNPq, CAPES, and PRONEX/CNPq/FUNCAP. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
|
| |
Call Number |
UA @ lucian @ c:irua:90922 |
Serial |
477 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Neek-Amal, M.; Peeters, F.M. |
|
| |
Title |
Lattice thermal properties of graphane : thermal contraction, roughness, and heat capacity |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
83 |
Issue |
23 |
Pages |
235437-235437,6 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Using atomistic simulations, we determine the roughness and the thermal properties of a suspended graphane sheet. As compared to graphene, we found that (i) hydrogenated graphene has a larger thermal contraction, (ii) the roughness exponent at room temperature is smaller, i.e., ≃ 1.0 versus ≃ 1.2 for graphene, (iii) the wavelengths of the induced ripples in graphane cover a wide range corresponding to length scales in the range 30125 Å at room temperature, and (iv) the heat capacity of graphane is estimated to be 29.32±0.23 J/mol K, which is 14.8% larger than that for graphene, i.e., 24.98±0.14 J/mol K. Above 1500 K, we found that graphane buckles when its edges are supported in the x-y plane. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000292253400011 |
Publication Date |
2011-06-30 |
|
| |
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 |
42 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
|
| |
Call Number |
UA @ lucian @ c:irua:90921 |
Serial |
1803 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Dixon, E.; Hadermann, J.; Hayward, M.A. |
|
| |
Title |
The synthesis and complex anion-vacancy ordered structure of La0.33Sr0.67MnO2.42 |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
|
| |
Volume |
184 |
Issue |
7 |
Pages |
1791-1799 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The low-temperature topotactic reduction of La0.33Sr0.67MnO3 with NaH results in the formation of La0.33Sr0.67MnO2.42. A combination of neutron powder and electron diffraction data show that La0.33Sr0.67MnO2.42 adopts a novel anion-vacancy ordered structure with a 6-layer OOTOOT' stacking sequence of the octahedral and tetrahedral layers (Pcmb, a=5.5804(1) Å, b=23.4104(7) Å, c=11.2441(3) Å). A significant concentration of anion vacancies at the anion site, which links neighbouring octahedral layers means that only 25% of the octahedral manganese coordination sites actually have 6-fold MnO6 coordination, the remainder being MnO5 square-based pyramidal sites. The chains of cooperatively twisted apex-linked MnO4 tetrahedra adopt an ordered -LRLR- arrangement within each tetrahedral layer. This is the first published example of a fully refined structure of this type which exhibits such intralayer ordering of the twisted tetrahedral chains. The rationale behind the contrasting structures of La0.33Sr0.67MnO2.42 and other previously reported reduced La1−xSrxMnO3−y phases is discussed. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
London |
Editor |
|
|
| |
Language |
|
Wos |
000292718500032 |
Publication Date |
2011-05-26 |
|
| |
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 |
8 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.299; 2011 IF: 2.159 |
|
| |
Call Number |
UA @ lucian @ c:irua:90885 |
Serial |
3600 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rakhimov, K.Y.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
|
| |
Title |
Wavepacket scattering of Dirac and Schrödinger particles on potential and magnetic barriers |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
23 |
Issue |
27 |
Pages |
275801,1-275801,16 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We investigate the dynamics of a charged particle moving in a graphene layer and in a two-dimensional electron gas, where it obeys the Dirac and the Schrödinger equations, respectively. The charge carriers are described as Gaussian wavepackets. The dynamics of the wavepackets is studied numerically by solving both quantum-mechanical and relativistic equations of motion. The scattering of such wavepackets by step-like magnetic and potential barriers is analysed for different values of wavepacket energy and width. We find: (1) that the average position of the wavepacket does not coincide with the classical trajectory, and (2) that, for slanted incidence, the path of the centre of mass of the wavepacket does not have to penetrate the barrier during the scattering process. Trembling motion of the charged particle in graphene is observed in the absence of an external magnetic field and can be enhanced by a substrate-induced mass term. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
London |
Editor |
|
|
| |
Language |
|
Wos |
000291993600009 |
Publication Date |
2011-06-18 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
32 |
Open Access |
|
|
| |
Notes |
; Discussions with A Matulis are gratefully acknowledged. KR is beneficiary of a mobility grant from the Belgian Federal Science Policy Office, co-funded by the European Commission and was supported in part by a grant of the Third World Academy of Sciences (ref. 09-188 RG/PHYS/AS-I). In addition, this work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the joint project CNPq-FWO, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
|
| |
Call Number |
UA @ lucian @ c:irua:90880 |
Serial |
3908 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Dzhurakhalov, A.A.; Peeters, F.M. |
|
| |
Title |
Structure and energetics of hydrogen chemisorbed on a single graphene layer to produce graphane |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
|
| |
Volume |
49 |
Issue |
10 |
Pages |
3258-3266 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Integrated Molecular Plant Physiology Research (IMPRES) |
|
| |
Abstract |
Chemisorption of hydrogen on graphene is studied using atomistic simulations with the second generation of reactive empirical bond order Brenner inter-atomic potential. The lowest energy adsorption sites and the most important metastable sites are determined. The H concentration is varied from a single H atom, to clusters of H atoms up to full coverage. We found that when two or more H atoms are present, the most stable configurations of H chemisorption on a single graphene layer are ortho hydrogen pairs adsorbed on one side or on both sides of the graphene sheet. The latter has the highest hydrogen binding energy. The next stable configuration is the orthopara pair combination, and then para hydrogen pairs. The structural changes of graphene caused by chemisorbed hydrogen are discussed and are compared with existing experimental data and other theoretical calculations. The obtained results will be useful for nanoengineering of graphene by hydrogenation and for hydrogen storage. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
|
| |
Language |
|
Wos |
000291959300014 |
Publication Date |
2011-04-15 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
6.337 |
Times cited |
46 |
Open Access |
|
|
| |
Notes |
; A.D. thanks M.W. Zhao for a useful correspondence. This work was supported by the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 6.337; 2011 IF: 5.378 |
|
| |
Call Number |
UA @ lucian @ c:irua:90877 |
Serial |
3275 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Vandenberghe, W.; Sorée, B.; Magnus, W.; Fischetti, M.V. |
|
| |
Title |
Generalized phonon-assisted Zener tunneling in indirect semiconductors with non-uniform electric fields : a rigorous approach |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
| |
Volume |
109 |
Issue |
12 |
Pages |
124503-124503,12 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
A general framework to calculate the Zener current in an indirect semiconductor with an externally applied potential is provided. Assuming a parabolic valence and conduction band dispersion, the semiconductor is in equilibrium in the presence of the external field as long as the electron-phonon interaction is absent. The linear response to the electron-phonon interaction results in a non-equilibrium system. The Zener tunneling current is calculated from the number of electrons making the transition from valence to conduction band per unit time. A convenient expression based on the single particle spectral functions is provided, enabling the evaluation of the Zener tunneling current under any three-dimensional potential profile. For a one-dimensional potential profile an analytical expression is obtained for the current in a bulk semiconductor, a semiconductor under uniform field, and a semiconductor under a non-uniform field using the WKB (Wentzel-Kramers-Brillouin) approximation. The obtained results agree with the Kane result in the low field limit. A numerical example for abrupt p-n diodes with different doping concentrations is given, from which it can be seen that the uniform field model is a better approximation than the WKB model, but a direct numerical treatment is required for low bias conditions. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
| |
Language |
|
Wos |
000292331200134 |
Publication Date |
2011-06-21 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.068 |
Times cited |
41 |
Open Access |
|
|
| |
Notes |
; William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). ; |
Approved |
Most recent IF: 2.068; 2011 IF: 2.168 |
|
| |
Call Number |
UA @ lucian @ c:irua:90808 |
Serial |
1325 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Kontozova-Deutsch, V.; Cardell, carolina; Urosevic, M.; Ruiz-Agudo, E.; Deutsch, F.; Van Grieken, R. |
|
| |
Title |
Characterization of indoor and outdoor atmospheric pollutants impacting architectural monuments : the case of San Jerónimo Monastery (Granada, Spain) |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Environmental earth sciences |
Abbreviated Journal |
|
|
| |
Volume |
63 |
Issue |
7/8 |
Pages |
1433-1445 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Indoor and outdoor concentrations of atmospheric gaseous pollutants as well as composition, size, and morphology of particulate matter have been investigated at the monastery of San Jerónimo in Granada (Southern Spain). Complementary micro- and nano-analytical techniques were applied; elemental and mineralogical composition and morphological characteristics of particulate matter were investigated combining electron probe microanalysis at the single particle level, and bulk aerosol samples were analyzed using energy-dispersive X-ray fluorescence, X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray analyzer and transmission electron microscopy (TEM). Microclimatic conditions at the monastery were monitored, and gas concentrations were assessed by means of diffusion tubes subsequently analyzed with ion chromatography. Results revealed high abundances of soil dust particles (aluminosilicates, calcite, dolomite, quartz), salt aerosols (chlorides, sulfates and ammonium-rich salts), and NO2 and SO2 both outdoors and indoors. Amorphous black carbon particles had surprisingly high abundances for Granada, a non-industrialized city. The composition of indoor particles corresponds to severe weathering affecting the construction materials and artworks inside the church; moreover their composition promotes a feedback process that intensifies the deterioration. Chemical reactions between chloride-rich salts and pigments from paintings were confirmed by TEM analyses. Indoors, blackening of surface decorative materials is fostered by particle re-suspension due to cleaning habits in the monastery (i.e. dusting). This is the first air quality study performed in a monument in the city of Granada with the aim of developing a strategy for preventive conservation. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000292744300003 |
Publication Date |
2010-07-19 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1866-6280 |
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:90766 |
Serial |
7630 |
|
| 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 |
Buysse, C. |
|
| |
Title |
Perovskite capillaries for gas separation in sustainable energy production |
Type |
Doctoral thesis |
| |
Year |
2011 |
Publication |
|
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
201 p. |
|
| |
Keywords |
Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
|
| |
Abstract |
|
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
|
Publication Date |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:90548 |
Serial |
8373 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Scipioni, R.; Matsubara, M.; Ruiz, E.; Massobrio, C.; Boero, M. |
|
| |
Title |
Thermal behavior of Si-doped fullerenes vs their structural stability at T = 0 K : a density functional study |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemical physics letters |
Abbreviated Journal |
Chem Phys Lett |
|
| |
Volume |
510 |
Issue |
1/3 |
Pages |
14-17 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We establish the topological conditions underlying the thermal stability of C30Si30 clusters. Two topologies have been considered: a segregated one, where Si and C atoms lie on neighboring and yet, separated parts of the cage, and a non-segregated one, where the number of SiC bonds is maximized. The segregated network is energetically favored against the non-segregated one, both structures being fully relaxed at T = 0 K. Conversely, the non-segregated structure is the only one stable at finite temperatures, regardless of the nature of the local states (d or p) included in the KleynmanBylander construction. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
| |
Language |
|
Wos |
000291478400002 |
Publication Date |
2011-05-20 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0009-2614; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
1.815 |
Times cited |
14 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 1.815; 2011 IF: 2.337 |
|
| |
Call Number |
UA @ lucian @ c:irua:90453 |
Serial |
3625 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Afanasov, I.M.; Van Tendeloo, G. |
|
| |
Title |
Zirconia-modified exfoliated graphite |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Inorganic materials |
Abbreviated Journal |
Inorg Mater+ |
|
| |
Volume |
47 |
Issue |
6 |
Pages |
603-608 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Zirconia has been incorporated into exfoliated graphite (EG) through the anodic polarization in the natural graphite-ZrO(NO3)2-HNO3-H2O system, followed by flash heating. The thermal properties of the oxidized graphites employed as precursors to EG have been studied by thermogravimetry in combination with differential scanning calorimetry, and the distribution of ZrO2 particles in the EG has been assessed by scanning and transmission electron microscopy. Conditions are described for the preparation of EG with bulk densities in the range 1.34.7 g/l and ZrO2 contents in the range 434 wt %. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000291698100008 |
Publication Date |
2011-05-24 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0020-1685;1608-3172; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
0.62 |
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 0.62; 2011 IF: 0.414 |
|
| |
Call Number |
UA @ lucian @ c:irua:90447 |
Serial |
3933 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Turner, S.; Lazar, S.; Freitag, B.; Egoavil, R.; Verbeeck, J.; Put, S.; Strauven, Y.; Van Tendeloo, G. |
|
| |
Title |
High resolution mapping of surface reduction in ceria nanoparticles |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
|
| |
Volume |
3 |
Issue |
8 |
Pages |
3385-3390 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Surface reduction of ceria nano octahedra with predominant {111} and {100} type surfaces is studied using a combination of aberration-corrected Transmission Electron Microscopy (TEM) and spatially resolved electron energy-loss spectroscopy (EELS) at high energy resolution and atomic spatial resolution. The valency of cerium ions at the surface of the nanoparticles is mapped using the fine structure of the Ce M4,5 edge as a fingerprint. The valency of the surface cerium ions is found to change from 4+ to 3+ owing to oxygen deficiency (vacancies) close to the surface. The thickness of this Ce3+ shell is measured using atomic-resolution Scanning Transmission Electron Microscopy (STEM)-EELS mapping over a {111} surface (the predominant facet for this ceria morphology), {111} type surface island steps and {100} terminating planes. For the {111} facets and for {111} surface islands, the reduction shell is found to extend over a single fully reduced surface plane and 12 underlying mixed valency planes. For the {100} facets the reduction shell extends over a larger area of 56 oxygen vacancy-rich planes. This finding provides a plausible explanation for the higher catalytic activity of the {100} surface facets in ceria. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
|
| |
Language |
|
Wos |
000293521700057 |
Publication Date |
2011-06-30 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
7.367 |
Times cited |
127 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 7.367; 2011 IF: 5.914 |
|
| |
Call Number |
UA @ lucian @ c:irua:90361UA @ admin @ c:irua:90361 |
Serial |
1458 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Hadermann, J.; Abakumov, A.M.; Turner, S.; Hafideddine, Z.; Khasanova, N.R.; Antipov, E.V.; Van Tendeloo, G. |
|
| |
Title |
Solving the structure of Li ion battery materials with precession electron diffraction : application to Li2CoPo4F |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
| |
Volume |
23 |
Issue |
15 |
Pages |
3540-3545 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The crystal structure of the Li2CoPO4F high-voltage cathode for Li ion rechargeable batteries has been completely solved from precession electron diffraction (PED) data, including the location of the Li atoms. The crystal structure consists of infinite chains of CoO4F2 octahedra sharing common edges and linked into a 3D framework by PO4 tetrahedra. The chains and phosphate anions together delimit tunnels filled with the Li atoms. This investigation demonstrates that PED can be successfully applied for obtaining structural information on a variety of Li-containing electrode materials even from single micrometer-sized crystallites. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
|
| |
Language |
|
Wos |
000293357100019 |
Publication Date |
2011-07-11 |
|
| |
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 |
46 |
Open Access |
|
|
| |
Notes |
Fwo; Bof |
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
|
| |
Call Number |
UA @ lucian @ c:irua:90357 |
Serial |
3053 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Philippaerts, A.; Goossens, S.; Vermandel, W.; Tromp, M.; Turner, S.; Geboers, J.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. |
|
| |
Title |
Design of Ru-zeolites for hydrogen-free production of conjugated linoleic acid |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemsuschem |
Abbreviated Journal |
Chemsuschem |
|
| |
Volume |
4 |
Issue |
6 |
Pages |
757-767 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
While conjugated vegetable oils are currently used as additives in the drying agents of oils and paints, they are also attractive molecules for making bio-plastics. Moreover, conjugated oils will soon be accepted as nutritional additives for functional food products. While current manufacture of conjugated vegetable oils or conjugated linoleic acids (CLAs) uses a homogeneous base as isomerisation catalyst, a heterogeneous alternative is not available today. This contribution presents the direct production of CLAs over Ru supported on different zeolites, varying in topology (ZSM-5, BETA, Y), Si/Al ratio and countercation (H+, Na+, Cs+). Ru/Cs-USY, with a Si/Al ratio of 40, was identified as the most active and selective catalyst for isomerisation of methyl linoleate (cis-9,cis-12 (C18:2)) to CLA at 165 °C. Interestingly, no hydrogen pre-treatment of the catalyst or addition of hydrogen donors is required to achieve industrially relevant isomerisation productivities, namely, 0.7 g of CLA per litre of solvent per minute. Moreover, the biologically most active CLA isomers, namely, cis-9,trans-11, trans-10,cis-12 and trans-9,trans-11, were the main products, especially at low catalyst concentrations. Ex situ physicochemical characterisation with CO chemisorption, extended X-ray absorption fine structure measurements, transmission electron microscopy analysis, and temperature-programmed oxidation reveals the presence of highly dispersed RuO2 species in Ru/Cs-USY(40). |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
|
| |
Language |
|
Wos |
000292214000009 |
Publication Date |
2011-04-20 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1864-5631; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
7.226 |
Times cited |
24 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 7.226; 2011 IF: 6.827 |
|
| |
Call Number |
UA @ lucian @ c:irua:90352 |
Serial |
660 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Scalise, E.; Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
|
| |
Title |
Structural and vibrational properties of amorphous GeO2 from first-principles |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
| |
Volume |
98 |
Issue |
20 |
Pages |
202110,1-202110,3 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
The structural and vibrational properties of amorphous germanium oxide (a-GeO<sub>2</sub>) are investigated using first-principles calculations based on density functional theory. We first generate an a-GeO<sub>2</sub> structure by first-principles molecular dynamics and analyze its structural properties. The vibrational spectra is then calculated within a density-functional approach. Both static and dynamic properties are in good agreement with experimental data. We next generate defects in our structure (oxygen vacancies with several density and charge states) and consider the most stable atomic configurations, focusing on the vibrational features of threefold coordinated O and divalent Ge centers. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
| |
Language |
|
Wos |
000290812100038 |
Publication Date |
2011-05-20 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.411 |
Times cited |
226 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
|
| |
Call Number |
UA @ lucian @ c:irua:90222 |
Serial |
3202 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Lindner, H.; Bogaerts, A. |
|
| |
Title |
Multi-element model for the simulation of inductively coupled plasmas : effects of helium addition to the central gas stream |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
Abbreviated Journal |
Spectrochim Acta B |
|
| |
Volume |
66 |
Issue |
6 |
Pages |
421-431 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
A model for an atmospheric pressure inductively coupled plasma (ICP) is developed which allows rather easy extension to a variable number of species and ionisation degrees. This encompasses an easy calculation of transport parameters for mixtures, ionisation and heat capacity. The ICP is modeled in an axisymmetric geometry, taking into account the gas streaming into a flowing ambient gas. A mixture of argon and helium is applied in the injector gas stream as it is often done in laser ablation ICP spectrometry. The results show a strong influence of the added helium on the center of the ICP, which is important for chemical analysis. The length of the central channel is significantly increased and the temperature inside is significantly higher than in the case of pure argon. This means that higher gas volume flow rates can be applied by addition of helium compared to the use of pure argon. This has the advantage that the gas velocity in the transport system towards the ICP can be increased, which allows shorter washout-times. Consequently, shorter measurement times can be achieved, e.g. for spatial mapping analyses in laser ablation ICP spectrometry. Furthermore, the higher temperature and the longer effective plasma length will increase the maximum size of droplets or particles injected into the ICP that are completely evaporated at the detection site. Thus, we expect an increase of the analytical performance of the ICP by helium addition to the injector gas. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
|
| |
Language |
|
Wos |
000293488700003 |
Publication Date |
2011-04-20 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0584-8547; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.241 |
Times cited |
28 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.241; 2011 IF: 2.876 |
|
| |
Call Number |
UA @ lucian @ c:irua:90190 |
Serial |
2209 |
|
| Permanent link to this record |
