Records |
Author |
Schattschneider, P.; Stöger-Pollach, M.; Löffler, S.; Steiger-Thirsfeld, A.; Hell, J.; Verbeeck, J. |
Title |
Sub-nanometer free electrons with topological charge |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
115 |
Issue |
|
Pages |
21-25 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The holographic mask technique is used to create freely moving electrons with quantized angular momentum. With electron optical elements they can be focused to vortices with diameters below the nanometer range. The understanding of these vortex beams is important for many applications. Here, we produce electron vortex beams and compare them to a theory of electrons with topological charge. The experimental results show excellent agreement with simulations. As an immediate application, fundamental experimental parameters like spherical aberration and partial coherence are determined. (C) 2012 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000302962400004 |
Publication Date |
2012-01-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
24 |
Open Access |
|
Notes |
vortex ECASJO_; |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
Call Number |
UA @ lucian @ c:irua:98279 |
Serial |
3344 |
Permanent link to this record |
|
|
|
Author |
Xiang, F.; Gupta, A.; Chaves, A.; Krix, Z.E.; Watanabe, K.; Taniguchi, T.; Fuhrer, M.S.; Peeters, F.M.; Neilson, D.; Milošević, M.V.; Hamilton, A.R. |
Title |
Intra-zero-energy Landau level crossings in bilayer graphene at high electric fields |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Nano letters |
Abbreviated Journal |
|
Volume |
23 |
Issue |
21 |
Pages |
9683-9689 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
The highly tunable band structure of the zero-energy Landau level (zLL) of bilayer graphene makes it an ideal platform for engineering novel quantum states. However, the zero-energy Landau level at high electric fields has remained largely unexplored. Here we present magnetotransport measurements of bilayer graphene in high transverse electric fields. We observe previously undetected Landau level crossings at filling factors nu = -2, 1, and 3 at high electric fields. These crossings provide constraints for theoretical models of the zero-energy Landau level and show that the orbital, valley, and spin character of the quantum Hall states at high electric fields is very different from low electric fields. At high E, new transitions between states at nu = -2 with different orbital and spin polarization can be controlled by the gate bias, while the transitions between nu = 0 -> 1 and nu = 2 -> 3 show anomalous behavior. |
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 |
|
Language |
|
Wos |
001102148900001 |
Publication Date |
2023-10-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
10.8 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 10.8; 2023 IF: 12.712 |
Call Number |
UA @ admin @ c:irua:201200 |
Serial |
9052 |
Permanent link to this record |
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|
|
Author |
Müller, M.; Lebedev, O.I.; Fischer, R.A. |
Title |
Gas-phase loading of [Zn4O(btb)2] (MOF-177) with organometallic CVD-precursors: inclusion compounds of the type [LnM]a@MOF-177 and the formation of Cu and Pd nanoparticles inside MOF-177 |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
18 |
Issue |
43 |
Pages |
5274-5281 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The highly porous and desolvated (activated) coordination polymer [Zn4O(btb)2] (btb = benzene-1,3,5-tribenzoate; MOF-177) was loaded with the organometallic compounds [Cp2Fe], [Cp*2Zn], [Cu(OCHMeCH2NMe2)2], [CpCuL] (L = PMe3, CNtBu) and [CpPd(3-C3H5)] via solvent-free adsorption from the gas-phase. The inclusion compounds of the type [LnM]a@MOF-177, where [LnM] indicates the respective compound and the parameter a denotes the number of molecules per formula unit of the MOF-177, were characterised by elemental analysis, FT-IR, solid-state NMR spectroscopy and by powder X-ray diffraction (PXRD). Remarkably high effective loadings of up to 11 molecules [Cp2Fe] and 10 molecules [CpPd(3-C3H5)] per cavity were determined. The analytical data prove that the host lattice and the guest molecules interact only by weak van-der-Waals forces without any significant change of the framework or the chemical nature of the included molecules. Cu nanoparticles showing the typical surface plasmon resonance at 580 nm and Pd nanoparticles of about 2.6 nm in size were formed inside the cavities of MOF-177 by the thermally activated hydrogenolysis of the inclusion compounds [CpCuCNtBu]2@MOF-177 and by photolysis of [CpPd(3-C3H5)]10@MOF-177 in an inert atmosphere (Ar). PXRD, FT-IR and NMR studies revealed that the MOF-177 matrix remained unchanged during the decomposition process of the precursors. N2 adsorption studies of the obtained materials Cu@MOF-177 (e.g. 10.6 wt.% Cu, 2309 m2 g-1) and Pd@MOF-177 (e.g. 32.5 wt.%, 1063 m2 g-1) reveal high remaining specific surface areas (Langmuir model). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000260487300015 |
Publication Date |
2008-10-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
65 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:75699 |
Serial |
1318 |
Permanent link to this record |
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|
|
Author |
Colla, M.-S.; Amin-Ahmadi, B.; Idrissi, H.; Malet, L.; Godet, S.; Raskin, J.-P.; Schryvers, D.; Pardoen, T. |
Title |
Dislocation-mediated relaxation in nanograined columnar palladium films revealed by on-chip time-resolved HRTEM testing |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
6 |
Issue |
6 |
Pages |
5922 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The high-rate sensitivity of nanostructured metallic materials demonstrated in the recent literature is related to the predominance of thermally activated deformation mechanisms favoured by a large density of internal interfaces. Here we report time-resolved high-resolution electron transmission microscopy creep tests on thin nanograined films using on-chip nanomechanical testing. Tests are performed on palladium, which exhibited unexpectedly large creep rates at room temperature. Despite the small 30-nm grain size, relaxation is found to be mediated by dislocation mechanisms. The dislocations interact with the growth nanotwins present in the grains, leading to a loss of coherency of twin boundaries. The density of stored dislocations first increases with applied deformation, and then decreases with time to drive additional deformation while no grain boundary mechanism is observed. This fast relaxation constitutes a key issue in the development of various micro- and nanotechnologies such as palladium membranes for hydrogen applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000348742300002 |
Publication Date |
2015-01-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-1723; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
34 |
Open Access |
|
Notes |
Iap7/21; Fwo G012012n |
Approved |
Most recent IF: 12.124; 2015 IF: 11.470 |
Call Number |
c:irua:122045 |
Serial |
731 |
Permanent link to this record |
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|
|
Author |
Hannibal, S.; Kettmann, P.; Croitoru, M.D.; Vagov, A.; Axt, V.M.; Kuhn, T. |
Title |
Quench dynamics of an ultracold Fermi gas in the BCS regime : spectral properties and confinement-induced breakdown of the Higgs mode |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
Volume |
91 |
Issue |
91 |
Pages |
043630 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The Higgs amplitude mode of the order parameter of an ultracold confined Fermi gas in the BCS regime after a quench of the coupling constant is analyzed theoretically. A characteristic feature is a damped oscillation which at a certain transition time changes into a rather irregular dynamics. We compare the numerical solution of the full set of nonlinear equations of motion for the normal and anomalous Bogoliubov quasiparticle excitations with a linearized approximation. In doing so the transition time as well as the difference between resonant systems, i.e., systems where the Fermi energy is close to a sub-band minimum, and off-resonant systems can be well understood and traced back to the system and geometry parameters. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000353448500005 |
Publication Date |
2015-04-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1094-1622; 1050-2947 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.925 |
Times cited |
10 |
Open Access |
|
Notes |
; M.D.C. acknowledges support by the BELSPO Back to Belgium Grant. ; |
Approved |
Most recent IF: 2.925; 2015 IF: NA |
Call Number |
UA @ lucian @ c:irua:132509 |
Serial |
4235 |
Permanent link to this record |
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|
|
Author |
Bogaerts, A.; Grozeva, M. |
Title |
Effect of helium/argon gas ratio in a He-Ar-Cu+ IR hollow-cathode discharge laser : modeling study and comparison with experiments |
Type |
A1 Journal article |
Year |
2003 |
Publication |
Applied physics B : lasers and optics |
Abbreviated Journal |
Appl Phys B-Lasers O |
Volume |
76 |
Issue |
3 |
Pages |
299-306 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The He-Ar-Cu+ IR laser operates in a hollow-cathode discharge, typically in a mixture of helium with a few-% Ar. The population inversion of the Cu+ ion levels, responsible for laser action, is attributed to asymmetric charge transfer between He+ ions and sputtered Cu atoms. The Ar gas is added to promote sputtering of the Cu cathode. In this paper, a hybrid modeling network consisting of several different models for the various plasma species present in a He-Ar-Cu hollow-cathode discharge is applied to investigate the effect of Ar concentration in the gas mixture on the discharge behavior, and to find the optimum He/Ar gas ratio for laser operation. It is found that the densities of electrons, Ar+ ions, Ar-m* metastable atoms, sputtered Cu atoms and Cu+ ions increase upon the addition of more Ar gas, whereas the densities of He+ ions, He-2(+) ions and He-m* metastable atoms drop considerably. The product of the calculated Cu atom and He+ ion densities, which determines the production rate of the upper laser levels, and hence probably also the laser output power, is found to reach a maximum around 1-5% Ar addition. This calculation result is compared to experimental measurements, and reasonable agreement has been reached. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000182758000017 |
Publication Date |
2004-03-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0946-2171;1432-0649; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.696 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.696; 2003 IF: 2.012 |
Call Number |
UA @ lucian @ c:irua:104125 |
Serial |
812 |
Permanent link to this record |
|
|
|
Author |
Barbier, M.; Papp, G.; Peeters, F.M. |
Title |
Snake states and Klein tunneling in a graphene Hall bar with a pn-junction |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
100 |
Issue |
16 |
Pages |
163121-163121,3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667] |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000303128500064 |
Publication Date |
2012-04-20 |
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 |
20 |
Open Access |
|
Notes |
; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-EuroGRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
Call Number |
UA @ lucian @ c:irua:99129 |
Serial |
3047 |
Permanent link to this record |
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|
|
Author |
Moro, G.; Campos, R.; Daems, E.; Moretto, L.M.; De Wael, K. |
Title |
Haem-mediated albumin biosensing : towards voltammetric detection of PFOA |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Bioelectrochemistry: an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry |
Abbreviated Journal |
|
Volume |
152 |
Issue |
|
Pages |
108428-7 |
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
The haem group is a promising redox probe for the design of albumin-based voltammetric sensors. Among the endogenous ligands carried by human serum albumin (hSA), haem is characterised by a reversible redox behaviour and its binding kinetics strongly depend on hSA’s conformation, which, in turn, depends on the presence of other ligands. In this work, the potential applicability of haem, especially hemin, as a redox probe was first tested in a proof-of-concept study using perfluorooctanoic acid (PFOA) as model analyte. PFOA is known to bind hSA by occupying Sudlow’s I site (FA7) which is spatially related to the haem-binding site (FA1). The latter undergoes a conformational change, which is expected to affect hemin’s binding kinetics. To verify this hypothesis, hemin:albumin complexes in the presence/absence of PFOA were first screened by UV–Vis spectroscopy. Once the complex formation was verified, haem was further characterised via electrochemical methods to estimate its electron transfer kinetics. The hemin:albumin:PFOA system was studied in solution, with the aim of describing the multiple equilibria at stake and designing an electrochemical assay for PFOA monitoring. This latter could be integrated with protein-based bioremediation approaches for the treatment of per- and polyfluoroalkyl substances polluted waters. Overall, our preliminary results show how hemin can be applied as a redox probe in albumin-based voltammetric sensing strategies. |
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 |
|
Language |
|
Wos |
000971630400001 |
Publication Date |
2023-03-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1567-5394 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
5 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 5; 2023 IF: 3.346 |
Call Number |
UA @ admin @ c:irua:195069 |
Serial |
8876 |
Permanent link to this record |
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|
Author |
Vishwakarma, M.; Thota, N.; Karakulina, O.; Hadermann, J.; Mehta, B.R. |
Title |
Role of graphene inter layer on the formation of the MoS2 – CZTS interface during growth |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
(icc-2017) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
The growth of MoS2 layer near the Mo/CZTS interface during sulphurization process can have an impact on back contact cell parameters (series resistance and fill factor) depending upon the thickness or quality of MoS2. This study reports the dependence of the thickness of interfacial MoS2 layer on the growth of graphene at the interface between molybdenum back contact and deposited CZTS layer. The graphene layer reduces the accumulation of Zn/ZnS, Sn/SnO2 and formation of pores near the MoS2-CZTS interface. The use of graphene as interface layer can be potentially useful for improving the quality of Mo/MoS2/CZTS interface. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
Amer inst physics |
Place of Publication |
Melville |
Editor |
|
Language |
|
Wos |
000436313003046 |
Publication Date |
2018-05-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
1953 |
Series Issue |
|
Edition |
|
ISSN |
978-0-7354-1648-2; 0094-243x; 0094-243x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
OpenAccess |
Notes |
; The authors acknowledge support provided by DST project. M.V. acknowledges IIT Delhi for MHRD fellowship. Prof. B. R. Mehta acknowledges the support of the Schlumberger chair professorship. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:153203 |
Serial |
5126 |
Permanent link to this record |
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|
Author |
Volkov, V.V.; van Heurck, C.; van Landuyt, J.; Amelinckx, S.; Zhukov, E.G.; Polulyak, E.S.; Novotortsev, V.M. |
Title |
Electron microscopy and X-ray study of the growth of FeCr2S4 spinel single crystals by chemical vapour transport |
Type |
A1 Journal article |
Year |
1993 |
Publication |
Crystal research and technology |
Abbreviated Journal |
Cryst Res Technol |
Volume |
28 |
Issue |
8 |
Pages |
1051-1061 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The growth features of FeCr2S4 spinel single crystals prepared by chemical vapour transport were studied by means of scanning electron microscopy, transmission electron microscopy, high resolution electron microscopy, electron diffraction and X-ray analysis. Our results indicate that the epitaxial growth of the new phases FeCr7S12 and FeCr8S12, both based on the NiAs structure, can essentially inhibit the growth of large FeCr2S4 spinel single crystals in the octahedral habit. The new phases are fully characterised and the effects of defect ordering in these new phases are also reported. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
A1993MN86700003 |
Publication Date |
2007-01-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0232-1300;1521-4079; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.935 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:6788 |
Serial |
952 |
Permanent link to this record |
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|
Author |
Nasr Esfahani, D.; Covaci, L.; Peeters, F.M. |
Title |
Electric-field-induced shift of the Mott metal-insulator transition in thin films |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
8 |
Pages |
085110-085110,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The ground-state properties of a paramagnetic Mott insulator at half-filling are investigated in the presence of an external electric field using the inhomogeneous Gutzwiller approximation for a single-band Hubbard model in a slab geometry. We find that the metal-insulator transition is shifted toward higher Hubbard repulsions by applying an electric field perpendicular to the slab. The main reason is the accumulation of charges near the surface. The spatial distribution of site-dependent quasiparticle weight shows that it is maximal in a few layers beneath the surface, while the central sites where the field is screened have a very low quasiparticle weight. Our results show that above a critical-field value, states near the surface will be metallic, while the bulk quasiparticle weight is extremely suppressed but never vanishing, even for large Hubbard repulsions above the bulk zero-field critical value. Below the critical-field value, our results hint toward an insulating state in which the electric field is totally screened and the slab is again at half-filling. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000300240100002 |
Publication Date |
2012-02-14 |
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 |
3 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:97208 |
Serial |
884 |
Permanent link to this record |
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|
|
Author |
Peeters, F.M.; Riva, C.; Varga, K. |
Title |
Trions in quantum wells |
Type |
A1 Journal article |
Year |
2002 |
Publication |
Few-body systems
T2 – International Workshop on Dynamics and Structure of Critically Stable, Quantum Few-Body Systems, OCT 08-12, 2001, LES HOUCHES, FRANCE |
Abbreviated Journal |
Few-Body Syst |
Volume |
31 |
Issue |
2-4 |
Pages |
97-100 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The ground-state energy of three-particle systems consisting of electrons and holes as found in semiconducting quantum wells is studied. The degree of confinement is determined by the quantum-well width and we can vary the dimensionality of the system from two to three dimensions. The energy levels of the system can further be altered by the application of an external magnetic field which is directed perpendicular to the well. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Wien |
Editor |
|
Language |
|
Wos |
000176115900005 |
Publication Date |
2003-03-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0177-7963;1432-5411; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.877 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.877; 2002 IF: 1.773 |
Call Number |
UA @ lucian @ c:irua:103378 |
Serial |
3733 |
Permanent link to this record |
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|
|
Author |
Castelano, L.K.; Hai, G.Q.; Partoens, B.; Peeters, F.M. |
Title |
Artificial molecular quantum rings under magnetic field influence |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
106 |
Issue |
7 |
Pages |
073702,1-073702,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The ground states of a few electrons confined in two vertically coupled quantum rings in the presence of an external magnetic field are studied systematically within the current spin-density functional theory. Electron-electron interactions combined with inter-ring tunneling affect the electronic structure and the persistent current. For small values of the external magnetic field, we recover the zero magnetic field molecular quantum ring ground state configurations. Increasing the magnetic field many angular momentum, spin, and isospin transitions are predicted to occur in the ground state. We show that these transitions follow certain rules, which are governed by the parity of the number of electrons, the single-particle picture, Hunds rules, and many-body effects. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
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Wos |
000270915600047 |
Publication Date |
2009-10-03 |
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 |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
Call Number |
UA @ lucian @ c:irua:86926 |
Serial |
155 |
Permanent link to this record |
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|
|
Author |
Galván Moya, J.E.; Lucena, D.; Ferreira, W.P.; Peeters, F.M. |
Title |
Magnetic particles confined in a modulated channel : structural transitions tunable by tilting a magnetic field |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
Volume |
89 |
Issue |
3 |
Pages |
032309-9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The ground state of colloidal magnetic particles in a modulated channel are investigated as a function of the tilt angle of an applied magnetic field. The particles are confined by a parabolic potential in the transversal direction while in the axial direction a periodic substrate potential is present. By using Monte Carlo simulations, we construct a phase diagram for the different crystal structures as a function of the magnetic field orientation, strength of the modulated potential, and the commensurability factor of the system. Interestingly, we found first-and second-order phase transitions between different crystal structures, which can be manipulated by the orientation of the external magnetic field. A reentrant behavior is found between two-and four-chain configurations, with continuous second-order transitions. Novel configurations are found consisting of frozen solitons of defects. By changing the orientation and/or strength of the magnetic field and/or the strength and periodicity of the substrate potential, the system transits through different phases. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
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Language |
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Wos |
000333702800015 |
Publication Date |
2014-03-31 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
11 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem programme of the Flemish government, CNPq, CAPES, FUNCAP (Pronex grant), the collaborative program CNPq-FWO-Vl, and the Brazilian program Science Without Borders CsF. Computational resources were provided by HPC infrastructure of University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC). ; |
Approved |
Most recent IF: 2.366; 2014 IF: 2.288 |
Call Number |
UA @ lucian @ c:irua:117217 |
Serial |
1886 |
Permanent link to this record |
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|
|
Author |
Ferreira, W.P.; Farias, G.A.; Carmona, H.A.; Peeters, F.M. |
Title |
Structural transitions in a classical two-dimensional molecule system |
Type |
A1 Journal article |
Year |
2002 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
Volume |
122 |
Issue |
12 |
Pages |
665-669 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The ground state of a classical two-dimensional (2D) system with a finite number of charge particles, trapped by two positive impurity charges localized at a distance (z(0)) from the. 2D plane and separated from each other by a distance chi(p) are obtained. The impurities are allowed to carry more than one positive charge. This classical system can form a 2D-like classical molecule that exhibits structural transitions and spontaneous symmetry breaking as function of the separation between the positive charges before it transforms into two 2D-like classical atoms. We also observe structural transitions as a function of the dielectric constant of the substrate which supports the charged particles, in addition to broken symmetry states and unbinding of particles. (C) 2002 Elsevier Science Ltd. All rights reserved. |
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 |
000177129500008 |
Publication Date |
2002-10-11 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0038-1098; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.554 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.554; 2002 IF: 1.671 |
Call Number |
UA @ lucian @ c:irua:95137 |
Serial |
3268 |
Permanent link to this record |
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|
|
Author |
Hao, Y.L.; Djotyan, A.P.; Avetisyan, A.A.; Peeters, F.M. |
Title |
D- shallow donor near a semiconductor-metal and a semiconductor-dielectric interface |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
23 |
Issue |
11 |
Pages |
115303,1-115313,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The ground state energy and the extent of the wavefunction of a negatively charged donor (D − ) located near a semiconductormetal or a semiconductordielectric interface are obtained. We apply the effective mass approximation and use a variational two-electron wavefunction that takes into account the influence of all image charges that arise due to the presence of the interface, as well as the correlation between the two electrons bound to the donor. For a semiconductormetal interface, the D − binding energy is enhanced for donor positions d > 1.5aB (aB is the effective Bohr radius) due to the additional attraction of the electrons with their images. When the donor approaches the interface (i.e. d < 1.5aB) the D − binding energy drops and eventually it becomes unbound. For a semiconductordielectric (or a semiconductorvacuum) interface the D − binding energy is reduced for any donor position as compared to the bulk case and the system becomes rapidly unbound when the donor approaches the interface. |
Address |
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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 |
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Wos |
000287969200013 |
Publication Date |
2011-03-04 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
5 |
Open Access |
|
Notes |
; This work was supported by the Belgian Science Policy (IAP) and the Brazilian Science Foundation CNPq. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (IAP). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
Call Number |
UA @ lucian @ c:irua:88828 |
Serial |
3528 |
Permanent link to this record |
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|
|
Author |
Saniz, R.; Partoens, B.; Peeters, F.M. |
Title |
Confinement effects on electron and phonon degrees of freedom in nanofilm superconductors : a Green function approach |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
6 |
Pages |
064510-64513 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The Green function approach to the Bardeen-Cooper-Schrieffer theory of superconductivity is used to study nanofilms. We go beyond previous models and include effects of confinement on the strength of the electron-phonon coupling as well as on the electronic spectrum and on the phonon modes. Within our approach, we find that in ultrathin films, confinement effects on the electronic screening become very important. Indeed, contrary to what has been advanced in recent years, the sudden increases of the density of states when new bands start to be occupied as the film thickness increases, tend to suppress the critical temperature rather than to enhance it. On the other hand, the increase of the number of phonon modes with increasing number of monolayers in the film leads to an increase in the critical temperature. As a consequence, the superconducting critical parameters in such nanofilms are determined by these two competing effects. Furthermore, in sufficiently thin films, the condensate consists of well-defined subcondensates associated with the occupied bands, each with a distinct coherence length. The subcondensates can interfere constructively or destructively giving rise to an interference pattern in the Cooper pair probability density. |
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 |
000315374100009 |
Publication Date |
2013-02-25 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). R.S. thanks M. R. Norman, B. Soree, and L. Komendova for useful comments. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:107072 |
Serial |
487 |
Permanent link to this record |
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Author |
Chen, J.-J.; Ke, X.; Van Tendeloo, G.; Meng, J.; Zhou, Y.-B.; Liao, Z.-M.; Yu, D.-P. |
Title |
Magnetotransport across the metal-graphene hybrid interface and its modulation by gate voltage |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
7 |
Issue |
7 |
Pages |
5516-5524 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The graphene-metal contact is very important for optimizing the performance of graphene based electronic devices. However, it is difficult to probe the properties of the graphene/metal interface directly via transport measurements in traditional graphene lateral devices, because the dominated transport channel is graphene, not the interface. Here, we employ the Au/graphene/Au vertical and lateral hybrid structure to unveil the metal-graphene interface properties, where the transport is dominated by the charge carriers across the interface. The magnetoresistance (MR) of Au/monolayer graphene/Au and Au/stacked two-layered graphene/Au devices is measured and modulated by gate voltage, demonstrating that the interface is a device. The gate-tunable MR is identified from the graphene lying on the SiO2 substrate and underneath the top metal electrode. Our unique structures couple the in-plane and out-of-plane transport and display linear MR with small amplitude oscillations at low temperatures. Under a magnetic field, the electronic coupling between the graphene edge states and the electrode leads to the appearance of quantum oscillations. Our results not only provide a new pathway to explore the intrinsic transport mechanism at the graphene/metal interface but also open up new vistas of magnetoelectronics. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000351372400050 |
Publication Date |
2015-02-19 |
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 |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
3 |
Open Access |
|
Notes |
246791 Countatoms |
Approved |
Most recent IF: 7.367; 2015 IF: 7.394 |
Call Number |
c:irua:125533 |
Serial |
1931 |
Permanent link to this record |
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|
Author |
Lian, M.; Shi, P.; Zhang, L.; Yao, W.; Gielis, J.; Niklas, K.J. |
Title |
A generalized performance equation and its application in measuring the Gini index of leaf size inequality |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Trees: structure and function |
Abbreviated Journal |
|
Volume |
37 |
Issue |
|
Pages |
1555-1565 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The goal of this study is to provide a rigorous tool to quantify the inequality of the leaf size distribution of an individual plant, thereby serving as a reference trait for quantifying plant adaptations to local environmental conditions. The tool to be presented and tested employs three components: (1) a performance equation (PE), which can produce flexible asymmetrical and symmetrical bell-shaped curves, (2) the Lorenz curve (i.e., the cumulative proportion of leaf size vs. the cumulative proportion of number of leaves), which is the basis for calculating, and (3) the Gini index, which measures the inequality of leaf size distribution. We sampled 12 individual plants of a dwarf bamboo and measured the area and dry mass of each leaf of each plant. We then developed a generalized performance equation (GPE) of which the PE is a special case and fitted the Lorenz curve to leaf size distribution using the GPE and PE. The GPE performed better than the PE in fitting the Lorenz curve. We compared the Gini index of leaf area distribution with that of leaf dry mass distribution and found that there was a significant difference between the two indices that might emerge from the scaling relationship between leaf dry mass and area. Nevertheless, there was a strong correlation between the two Gini indices (r2 = 0.9846). This study provides a promising tool based on the GPE for quantifying the inequality of leaf size distributions across individual plants and can be used to quantify plant adaptations to local environmental conditions. |
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 |
001069570200001 |
Publication Date |
2023-08-26 |
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 |
|
Edition |
|
ISSN |
0931-1890; 1432-2285 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.3 |
Times cited |
|
Open Access |
Not_Open_Access: Available from 26.02.2024 |
Notes |
|
Approved |
Most recent IF: 2.3; 2023 IF: 1.842 |
Call Number |
UA @ admin @ c:irua:199562 |
Serial |
8874 |
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 |
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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 |
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ISSN |
0021-8502; 1879-1964 |
ISBN |
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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 |
Yan, M.; Bogaerts, A.; Gijbels, R. |
Title |
Kinetic modeling of relaxation phenomena after photodetachment in a rf electronegative SiH4 discharge |
Type |
A1 Journal article |
Year |
2001 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
63 |
Issue |
2Part 2 |
Pages |
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The global relaxation process after pulsed laser induced photodetachment in a rf electronegative SIH4 discharge is studied by a self-consistent kinetic one-dimensional particle-in-cell-Monte Carlo model. Our results reveal a comprehensive physical picture of the relaxation process, including the main plasma variables, after a perturbation up to the full recovery of the steady state. A strong influence of the photodetachment on the discharge is found, which results from an increase of the electron density, leading to a weaker bulk field, and hence to a drop in the high energy tail of the electron energy distribution function (EEDF), a reduction of the reaction rates of electron impact attachment and ionization, and a subsequent decrease of the positive and negative ion densities. All the plasma quantities related to electrons recover synchronously. The recovery time of the ion densities is about 1-2 orders of magnitude longer than that of the electrons due to different recovery mechanisms. The modeled behavior of all the charged particles agrees very well with experimental results from the literature. In addition, our work clarifies some unclear processes assumed in the literature, such as the relaxation of the EEDF, the evolution of the electric field, and the recovery of negative ions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
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Language |
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Wos |
000167022500057 |
Publication Date |
2002-07-27 |
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 |
1063-651X;1095-3787; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.366; 2001 IF: 2.235 |
Call Number |
UA @ lucian @ c:irua:34148 |
Serial |
1757 |
Permanent link to this record |
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Author |
Trenchev, G.; Kolev, S.; Wang, W.; Ramakers, M.; Bogaerts, A. |
Title |
CO2Conversion in a Gliding Arc Plasmatron: Multidimensional Modeling for Improved Efficiency |
Type |
A1 Journal article |
Year |
2017 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
121 |
Issue |
44 |
Pages |
24470-24479 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The gliding arc plasmatron (GAP) is a highly efficient atmospheric plasma source, which is very promising for CO2 conversion applications. To understand its operation principles and to improve its application, we present here comprehensive modeling results, obtained by means of computational fluid dynamics simulations and plasma modeling. Because of the complexity of the CO2 plasma, a full 3D plasma model would be computationally impractical. Therefore, we combine a 3D turbulent gas flow model with a 2D plasma and gas heating model in order to calculate the plasma parameters and CO2 conversion characteristics. In addition, a complete 3D gas flow and plasma model with simplified argon chemistry is used to evaluate the gliding arc evolution in space and time. The calculated values are compared with experimental data from literature as much as possible in order to validate the model. The insights obtained in this study are very helpful for improving the application of CO2 conversion, as they allow us to identify the limiting factors in the performance, based on which solutions can be provided on how to further improve the capabilities of CO2 conversion in the GAP. |
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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 |
000415140400014 |
Publication Date |
2017-11-09 |
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 |
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ISSN |
1932-7447 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
H2020 Marie Sklodowska-Curie Actions, 657304 ; Fonds Wetenschappelijk Onderzoek, 11U5316N G038316N ; |
Approved |
Most recent IF: 4.536 |
Call Number |
PLASMANT @ plasmant @c:irua:147193 |
Serial |
4765 |
Permanent link to this record |
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Author |
Volkov, V.V.; Van Tendeloo, G.; Vargaftik, M.N.; Stolyarov, I.P.; Moiseev, I.I. |
Title |
Giant Pd clusters observed by high resolution electron microscopy |
Type |
A1 Journal article |
Year |
1993 |
Publication |
Mendeleev communications |
Abbreviated Journal |
Mendeleev Commun |
Volume |
|
Issue |
5 |
Pages |
187-188 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The giant cationic palladium clusters, approximate formula Pd561L60(OAc)180 (L = Dipy, Phen), were characterized by electron diffraction and high resolution microscopy to contain an FCC metal core, most of the larger Pd particles (8 nm) exhibiting multiple twinning, evidence for a distorted icosahedral structure. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
A1993MJ24700001 |
Publication Date |
0000-00-00 |
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 |
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ISSN |
0959-9436 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.34 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:102959 |
Serial |
1340 |
Permanent link to this record |
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Author |
Gu, J.-G.; Zhang, Y.; Gao, M.-X.; Wang, H.-Y.; Zhang, Q.-Z.; Yi, L.; Jiang, W. |
Title |
Enhancement of surface discharge in catalyst pores in dielectric barrier discharges |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
125 |
Issue |
15 |
Pages |
153303 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The generation of high-density plasmas on the surface of porous catalysts is very important for plasma catalysis, as it determines the active surface of the catalyst that is available for the reaction. In this work, we investigate the mechanism of surface and volume plasma streamer formation and propagation near micro-sized pores in dielectric barrier discharges operating in air at atmospheric pressure. A two-dimensional particle-in-cell/ Monte Carlo collision model is used to model the individual kinetic behavior of plasma species. Our calculations indicate that the surface discharge is enhanced on the surface of the catalyst pores compared with the microdischarge inside the catalyst pores. The reason is that the surface ionization wave induces surface charging along the catalyst pore sidewalls, leading to a strong electric field along the pore sidewalls, which in turn further enhances the surface discharge. Therefore, highly concentrated reactive species occur on the surfaces of the catalyst pores, indicating high-density plasmas on the surface of porous catalysts. Indeed, the maximum electron impact excitation and ionization rates occur on the pore surface, indicating the more pronounced production of excited state and electron-ion pairs on the pore surface than inside the pore, which may profoundly affect the plasma catalytic process. Published under license by AIP Publishing. |
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 |
000465441200022 |
Publication Date |
2019-04-15 |
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 |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
4 |
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 2.068 |
Call Number |
UA @ admin @ c:irua:160397 |
Serial |
5273 |
Permanent link to this record |
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Author |
Lang, X.; Ouyang, Y.; Vandewalle, L.A.; Goshayeshi, B.; Chen, S.; Madanikashani, S.; Perreault, P.; Van Geem, K.M.; van Geem, K.M. |
Title |
Gas-solid hydrodynamics in a stator-rotor vortex chamber reactor |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
Volume |
446 |
Issue |
5 |
Pages |
137323-12 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The gas-solid vortex reactor (GSVR) has enormous process intensification potential. However the huge gas consumption can be a serious disadvantage for the GSVR in some applications such as fast pyrolysis. In this work, we demonstrate a recent novel design, where a stator-rotor vortex chamber (STARVOC) is driven by the fluid's kinetic energy, to decouple the solids bed rotation and gas. Gas-solid fluidization by using air and monosized aluminum balls was performed to investigate the hydrodynamics. A constructed fluidization flow regime map for a fixed solids loading of 100 g shows that the bed can only be fluidized for a rotation speed between 200 and 400 RPM. Below 200 RPM, particles settle down on the bottom plate and cannot form a stable bed due to inertia and friction. Above 400 RPM, the bed cannot be fluidized with superficial velocities up to 1.8 m/s (air flow rate of 90 Nm(3)/h). The bed thickness shows some non-uniformities, being smaller at the top of the bed than at the bottom counterpart. However by increasing the air flow rate or rotation speed the axial nonuniformity can be resolved. The bed pressure drop first increases with increasing gas flow rate and then levels off, showing similar characteristics as conventional fluidized beds. Theoretical pressure drops calculated from mathematical models such as Kao et al. model agree well with experimental measurements. Particle velocity discrepancies between the top and bottom particles reveal that the impact of gravity cannot be completely neglected. Design guidelines and possible applications for further development of STARVOC concept are proposed based on fundamental data provided in this work. |
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 |
000833418100006 |
Publication Date |
2022-06-01 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1385-8947; 1873-3212 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
15.1 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 15.1 |
Call Number |
UA @ admin @ c:irua:189283 |
Serial |
7167 |
Permanent link to this record |
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|
|
Author |
Zhang, Z.; Rosalie, J.M.; Medhekar, N.V.; Bourgeois, L. |
Title |
Resolving the FCC/HCP interfaces of the \gamma'(Ag2Al) precipitate phase in aluminium |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
Volume |
174 |
Issue |
174 |
Pages |
116-130 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The gamma'(Ag2Al) phase in the Al-Ag alloy system has served as a textbook example for understanding phase transformations, precipitating hexagonal close-packed (HCP) crystals in the face-centred cubic (FCC) aluminium matrix. The gamma' precipitates display fully coherent interfaces at their broad facets and semicoherent interfaces at their edges. Shockley partial dislocations are expected to decorate the semicoherent interface due to the FCC-HCP structural transformation. Determining the exact locations and core structures of interfacial dislocations, however, remains challenging. In this study, we used aberration-corrected scanning transmission electron microscopy and atomistic simulations to re-visit this classical system. We characterised and explained the Ag segregation at coherent interfaces in the early stage of precipitation. For semicoherent interfaces, interfacial dislocations and reconstructions were revealed by bridging advanced microstructure characterisation and atomistic simulations. In particular, we discovered a new FCC/HCP interfacial structure that displays a unique combination of Shockley partial, Lomer-Cottrell and Hirth dislocations that evolve from the known interfacial structure purely composed by Shockley partial dislocations. Our findings show that the FCC-HCP transformation is more complex than hitherto considered, due to the interplay between structure and composition confined at interfaces. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
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 |
000474501300011 |
Publication Date |
2019-05-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1359-6454 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.301 |
Times cited |
3 |
Open Access |
|
Notes |
; The authors acknowledge funding from the Australian Research Council (LE0454166, LE110100223), the Victorian State Government and Monash University for instrumentation, and use of the facilities within the Monash Centre for Electron Microscopy. LB and NM acknowledge the financial support of the Australian Research Council (DP150100558). The authors also gratefully acknowledge the computational support from Monash Advanced Research Computing Hybrid, the National Computational Infrastructure and Pawsey Supercomputing Centre. ZZ is thankful to Monash University for a Monash Graduate Scholarship, a Monash International Postgraduate Research Scholarship and a Monash Centre for Electron Microscopy Postgraduate Scholarship. ZZ is indebted to Matthew Weyland for his training in aberration-corrected electron microscopy, Scott Findlay for his help on image simulations, Xiang Gao for alloy casting and Ian Polmear for discussions. ; |
Approved |
Most recent IF: 5.301 |
Call Number |
UA @ admin @ c:irua:161192 |
Serial |
5395 |
Permanent link to this record |
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|
|
Author |
Idrissi, H.; Ghidelli, M.; Béché, A.; Turner, S.; Gravier, S.; Blandin, J.-J.; Raskin, J.-P.; Schryvers, D.; Pardoen, T. |
Title |
Atomic-scale viscoplasticity mechanisms revealed in high ductility metallic glass films |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
9 |
Issue |
1 |
Pages |
13426 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The fundamental plasticity mechanisms in thin freestanding Zr65Ni35 metallic glass films are investigated in order to unravel the origin of an outstanding strength/ductility balance. The deformation process is homogenous until fracture with no evidence of catastrophic shear banding. The creep/relaxation behaviour of the films was characterized by on-chip tensile testing, revealing an activation volume in the range 100–200 Å3. Advanced high-resolution transmission electron microscopy imaging and spectroscopy exhibit a very fine glassy nanostructure with well-defined dense Ni-rich clusters embedded in Zr-rich clusters of lower atomic density and a ~2–3 nm characteristic length scale. Nanobeam electron diffraction analysis reveals that the accumulation of plastic deformation at roomtemperature
correlates with monotonously increasing disruption of the local atomic order. These results provide experimental evidences of the dynamics of shear transformation zones activation in metallic glasses. The impact of the nanoscale structural heterogeneities on the mechanical properties including the rate dependent behaviour is discussed, shedding new light on the governing plasticity mechanisms in metallic glasses with initially heterogeneous atomic arrangement. |
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 |
000486139700008 |
Publication Date |
2019-09-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
|
Open Access |
|
Notes |
H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the FNRS under Grant PDR – T.0178.19. FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’) and Hercules fund ‘Direct electron detector for soft matter TEM’ from Flemish Government are acknowledged. |
Approved |
Most recent IF: 4.259 |
Call Number |
EMAT @ emat @c:irua:162786 |
Serial |
5375 |
Permanent link to this record |
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Author |
Fukuhara, S.; Bal, K.M.; Neyts, E.C.; Shibuta, Y. |
Title |
Entropic and enthalpic factors determining the thermodynamics and kinetics of carbon segregation from transition metal nanoparticles |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
171 |
Issue |
|
Pages |
806-813 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The free energy surface (FES) for carbon segregation from nickel nanoparticles is obtained from advanced molecular dynamics simulations. A suitable reaction coordinate is developed that can distinguish dissolved carbon atoms from segregated dimers, chains and junctions on the nanoparticle surface. Because of the typically long segregation time scale (up to ms), metadynamics simulations along the developed reaction coordinate are used to construct FES over a wide range of temperatures and carbon concentrations. The FES revealed the relative stability of different stages in the segregation process, and free energy barriers and rates of the individual steps could then be calculated and decomposed into enthalpic and entropic contributions. As the carbon concentration in the nickel nanoparticle increases, segregated carbon becomes more stable in terms of both enthalpy and entropy. The activation free energy of the reaction also decreases with the increase of carbon concentration, which can be mainly attributed to entropic effects. These insights and the methodology developed to obtain them improve our understanding of carbon segregation process across materials science in general, and the nucleation and growth of carbon nanotube in particular. |
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 |
000598371500084 |
Publication Date |
2020-09-25 |
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 |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
Scientific Research, 19H02415 ; JSPS, 18J22727 ; Japan Society for the Promotion of Science; JSPS; JSPS; FWO; Research Foundation; Flanders, 12ZI420N ; This work was supported by Grant-in-Aid for Scientific Research (B) (No.19H02415) and Grant-in-Aid for JSPS Research Fellow (No.18J22727) from Japan Society for the Promotion of Science (JSPS), Japan. S.F. was supported by JSPS through the Program for 812 |
Approved |
Most recent IF: 6.337 |
Call Number |
PLASMANT @ plasmant @c:irua:172452 |
Serial |
6421 |
Permanent link to this record |
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Author |
Simonsen, K.P.; Poulsen, J.N.; Vanmeert, F.; Ryhl-Svendsen, M.; Bendix, J.; Sanyova, J.; Janssens, K.; Mederos-Henry, F. |
Title |
Formation of zinc oxalate from zinc white in various oil binding media: the influence of atmospheric carbon dioxide by reaction with 13CO2 |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Heritage science |
Abbreviated Journal |
|
Volume |
8 |
Issue |
1 |
Pages |
126 |
Keywords |
A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The formation of metal oxalates in paintings has recently gained a great deal of interest within the field of heritage science as several types of oxalate compounds have been identified in oil paintings. The present work investigates the formation of metal oxalates in linseed oil in the presence of the artists' pigments zinc white, calcite, lead white, zinc yellow, chrome yellow, cadmium yellow, cobalt violet, and verdigris. The oil paint films were artificially photo-aged by exposure to UVA light at low and high relative humidity, and afterwards analysed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The results showed that, compared to the other pigments investigated, zinc white is especially prone to metal oxalate formation and that high humidity is a crucial factor in this process. Consequently, the reactivity and photo-aging of ZnO in various oil binding media was investigated further under simulated solar radiation and at high relative humidity levels. ATR-FTIR showed that zinc oxalate is formed in all oil binding media while X-ray powder diffraction (PXRD) revealed it was mainly present in an amorphous state. To examine whether atmospheric CO2(g) has any influence on the formation of zinc oxalate, experiments with isotopically enriched (CO2(g))-C-13 were performed. Based on ATR-FTIR measurements, neither (ZnC2O4)-C-13 nor (ZnCO3)-C-13 were formed which suggests that the carbon source for the oxalate formation is most likely the paint itself (and its oil component) and not the surrounding atmosphere. |
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 |
000596527000001 |
Publication Date |
2020-12-07 |
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 |
2050-7445 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.5 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.5; 2020 IF: NA |
Call Number |
UA @ admin @ c:irua:174381 |
Serial |
7979 |
Permanent link to this record |
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Author |
Ceyhan, E.; Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. |
Title |
Electronic and magnetic properties of single-layer FeCl₂ with defects |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
103 |
Issue |
1 |
Pages |
014106 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The formation of lattice defects and their effect on the electronic properties of single-layer FeCl2 are investigated by means of first-principles calculations. Among the vacancy defects, namely mono-, di-, and three-Cl vacancies and mono-Fe vacancy, the formation of mono-Cl vacancy is the most preferable. Comparison of two different antisite defects reveals that the formation of the Fe-antisite defect is energetically preferable to the Cl-antisite defect. While a single Cl vacancy leads to a 1 mu(B) decrease in the total magnetic moment of the host lattice, each Fe vacant site reduces the magnetic moment by 4 mu(B). However, adsorption of an excess Cl atom on the surface changes the electronic structure to a ferromagnetic metal or to a ferromagnetic semiconductor depending on the adsorption site without changing the ferromagnetic state of the host lattice. Both Cl-antisite and Fe-antisite defected domains change the magnetic moment of the host lattice by -1 mu(B) and +3 mu(B), respectively. The electronic ground state of defected structures reveals that (i) single-layer FeCl2 exhibits half-metallicity under the formation of vacancy and Cl-antisite defects; (ii) ferromagnetic metallicity is obtained when a single Cl atom is adsorbed on upper-Cl and Fe sites, respectively; and (iii) ferromagnetic semiconducting behavior is found when a Cl atom is adsorbed on a lower-Cl site or a Fe-antisite defect is formed. Simulated scanning electron microscope images show that atomic-scale identification of defect types is possible from their electronic charge density. Further investigation of the periodically Fe-defected structures reveals that the formation of the single-layer FeCl3 phase, which is a dynamically stable antiferromagnetic semiconductor, is possible. Our comprehensive analysis on defects in single-layer FeCl2 will complement forthcoming experimental observations. |
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 |
000606969400002 |
Publication Date |
2021-01-13 |
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 |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
Not_Open_Access |
Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and by Flemish Supercomputer Center (VSC). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. M.Y. was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ admin @ c:irua:176039 |
Serial |
6689 |
Permanent link to this record |