| Records |
| Author |
Abakumov, A.M.; d' Hondt, H.; Rossell, M.D.; Tsirlin, A.A.; Gutnikova, O.; Filimonov, D.S.; Schnelle, W.; Rosner, H.; Hadermann, J.; Van Tendeloo, G.; Antipov, E.V. |
| Title |
Coupled anion and cation ordering in Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficientperovskites |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
183 |
Issue |
12 |
Pages |
2845-2854 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficient perovskites were prepared using a solid-state reaction in evacuated sealed silica tubes. Transmission electron microscopy and 57Fe Mössbauer spectroscopy evidenced a complete A-cations and oxygen vacancies ordering. The structure model was further refined by ab initio structure relaxation, based on density functional theory calculations. The compounds crystallize in a tetragonal a≈2√2ap≈11.3 Å, с≈4сp≈16 Å unit cell (ap: parameter of the perovskite subcell) with the P42/mnm space group. Oxygen vacancies reside in the (FeO5/4□3/4) layers, comprising corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids, which are sandwiched between the layers of the FeO6 octahedra. Smaller R atoms occupy the 9-fold coordinated position, whereas the 10-fold coordinated positions are occupied by larger Sr atoms. The Fe sublattice is ordered aniferromagnetically up to at least 500 K, while the rare-earth sublattice remains disordered down to 2 K. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000285431100014 |
Publication Date |
2010-10-02 |
| 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; 2010 IF: 2.261 |
| Call Number |
UA @ lucian @ c:irua:88071 |
Serial |
533 |
| Permanent link to this record |
| |
|
| |
| Author |
Connolly, M.R.; Bemding, S.J.; Milošević, M.V.; Clem, J.R.; Tamegai, T. |
| Title |
Continuum versus discrete flux behaviour in large mesoscopic Bi2Sr2CaCu2O8+\delta disks |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
| Volume |
470 |
Issue |
S:1 |
Pages |
S896-S897 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We have used scanning Hall probe and local Hall magnetometry measurements to map flux profiles in superconducting Bi2Sr2CaCu2O8+δ disks whose diameters span the crossover between the bulk and mesoscopic vortex regimes. The behaviour of large disks (greater-or-equal, slanted20 μm diameter) is well described by analytic models that assume a continuous distribution of flux in the sample. Small disks (less-than-or-equals, slant10 μm diameter), on the other hand, exhibit clear signatures of the underlying discrete vortex structure as well as competition between triangular Abrikosov ordering and the formation of shell structures driven by interactions with circulating edge currents. At low fields we are able to directly observe the characteristic mesoscopic compression of vortex clusters which is linked to oscillations in the diameter of the vortex dome in increasing magnetic fields. At higher fields, where single vortex resolution is lost, we are still able to track configurational changes in the vortex patterns, since competing vortex orders impose unmistakable signatures on local magnetisation curves. Our observations are in excellent agreement with molecular-dynamics numerical simulations which lead us to a natural definition of the lengthscale for the crossover between discrete and continuum behaviour in our system. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000286075700384 |
Publication Date |
2009-11-20 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
1.404 |
Times cited |
|
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 1.404; 2010 IF: 1.415 |
| Call Number |
UA @ lucian @ c:irua:88069 |
Serial |
494 |
| Permanent link to this record |
| |
|
| |
| Author |
Verberck, B. |
| Title |
Symmetry-adapted rotator functions for molecules in cylindrical confinement |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
International journal of molecular sciences |
Abbreviated Journal |
Int J Mol Sci |
| Volume |
12 |
Issue |
1 |
Pages |
317-333 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We present a general description of the formalism of symmetry-adapted rotator functions (SARFs) for molecules in cylindrical confinement. Molecules are considered as clusters of interaction centers (ICs), can have any symmetry, and can display different types of ICs. Cylindrical confinement can be realized by encapsulation in a carbon nanotube (CNT). The potential energy of a molecule surrounded by a CNT can be calculated by evaluating a limited number of terms of an expansion into SARFs, which offers a significant reduction of the computation time. Optimal molecular orientations can be deduced from the resulting potential energy landscape. Examples, including the case of a molecule with cubic symmetry inside a CNT, are discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000286583400017 |
Publication Date |
2011-01-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1422-0067; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.226 |
Times cited |
1 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 3.226; 2011 IF: NA |
| Call Number |
UA @ lucian @ c:irua:88048 |
Serial |
3402 |
| Permanent link to this record |
| |
|
| |
| Author |
Neek-Amal, M.; Peeters, F.M. |
| Title |
Buckled circular monolayer graphene : a graphene nano-bowl |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
23 |
Issue |
4 |
Pages |
045002-045002,8 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the stability of circular monolayer graphene subjected to a radial load using non-equilibrium molecular dynamics simulations. When monolayer graphene is radially stressed, after some small circular strain (~0.4%) it buckles and bends into a new bowl-like shape. Young's modulus is calculated from the linear relation between stress and strain before the buckling threshold, which is in agreement with experimental results. The prediction of elasticity theory for the buckling threshold of a radially stressed plate is presented and its results are compared to the one of our atomistic simulation. The Jarzynski equality is used to estimate the difference between the free energy of the non-compressed states and the buckled states. From a calculation of the free energy we obtain the optimum radius for which the system feels the minimum boundary stress. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000286142800003 |
Publication Date |
2010-12-16 |
| 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 |
27 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
| Call Number |
UA @ lucian @ c:irua:88043 |
Serial |
259 |
| Permanent link to this record |
| |
|
| |
| Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
| Title |
Second-order multiple-quanta flux entry into a perforated spherical mesoscopic superconductor |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
21 |
Pages |
214501-214501,7 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Flux entry in type-II superconductors without prominent symmetry is a first-order phase transition, where flux enters conventionally gradual in units of a flux quantum. Here we show that neither is necessarily the case in a mesoscopic superconducting sphere with a perforation. In axially applied magnetic field, vortices initially occupy the hole, and can oppose further flux entry in the sample. As a result, multiple-quanta flux entry is found at significantly higher field, and it can manifest as a second-order transition due to suppressed geometric barrier at the equatorial belt of the sample. At high fields a new state is found, with gradually destroyed condensate from the equator inwards, the exact opposite of surface superconductivity. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000286737800007 |
Publication Date |
2010-12-02 |
| 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 |
2 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-V1), the Belgian Science Policy (IAP), and the ESF “Nanoscience and Engineering in Superconductivity” program. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:88039 |
Serial |
2957 |
| Permanent link to this record |
| |
|
| |
| Author |
Shanenko, A.A.; Milošević, M.V.; Peeters, F.M. |
| Title |
Extended Ginzburg-Landau formalism for two-band superconductors |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
106 |
Issue |
4 |
Pages |
047005-047005,4 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Recent observation of unusual vortex patterns in MgB2 single crystals raised speculations about possible type-1.5 superconductivity in two-band materials, mixing the properties of both type-I and type-II superconductors. However, the strict application of the standard two-band Ginzburg-Landau (GL) theory results in simply proportional order parameters of the two bandsand does not support the type-1.5 behavior. Here we derive the extended GL formalism (accounting all terms of the next order over the small τ=1-T/Tc parameter) for a two-band clean s-wave superconductor and show that the two condensates generally have different spatial scales, with the difference disappearing only in the limit T→Tc. The extended version of the two-band GL formalism improves the validity of GL theory below Tc and suggests revisiting the earlier calculations based on the standard model. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000286734100010 |
Publication Date |
2011-01-27 |
| 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 |
84 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. Discussions with M. D. Croitoru are gratefully acknowledged. ; |
Approved |
Most recent IF: 8.462; 2011 IF: 7.370 |
| Call Number |
UA @ lucian @ c:irua:88038 |
Serial |
1154 |
| Permanent link to this record |
| |
|
| |
| Author |
Salluzzo, M.; Aruta, C.; Ausanio, G.; Bals, S.; d' Agostino, A.; Maglione, M.G. |
| Title |
Role of Nd/Ba substitution on the growth mode and on the structural properties of Nd-rich Re1(NdxBa2-x)Cu3O7-\delta (Re=Nd, Y) thin films |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
| Volume |
372-376 |
Issue |
2 |
Pages |
675-678 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Thin films of the superconducting Nd1+xBa2−xCu3O7−δ (NBCO) and Y1(NdxBa2−x)Cu3O7−δ (YNBCO) compounds have been deposited by dc magnetron sputtering and diode high pressure oxygen sputtering. Different techniques, including scanning tunneling microscopy, atomic force microscopy, X-ray diffraction and transmission electron microscopy (TEM) have been used to study the film microstructures and the surface morphology. It is shown that the Nd/Ba exchange promotes a 2D heteroepitaxial growth in the case of the NBCO films deposited on (1 0 0) SrTiO3 substrates, with a suppression of the characteristic 3D spirals structures. On the contrary in YNBCO the Nd/Ba exchange does not provide a driving force for the suppression of screw-dislocations, since spirals or towers originated by screw and half loop dislocations are observed on the surface. TEM reveals that anti-phase boundaries are eliminated during the growth of NBCO films thanks to the Nd/Ba exchange while this mechanism is not operating in the case of YNBCO films. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000178018800024 |
Publication Date |
2002-08-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.404 |
Times cited |
5 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.404; 2002 IF: 0.912 |
| Call Number |
UA @ lucian @ c:irua:87909 |
Serial |
2917 |
| Permanent link to this record |
| |
|
| |
| Author |
Li, Y.; Tan, H.; Yang, X.-Y.; Goris, B.; Verbeeck, J.; Bals, S.; Colson, P.; Cloots, R.; Van Tendeloo, G.; Su, B.-L. |
| Title |
Well shaped Mn3O4 nano-octahedra with anomalous magnetic behavior and enhanced photodecomposition properties |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Small |
Abbreviated Journal |
Small |
| Volume |
7 |
Issue |
4 |
Pages |
475-483 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Very uniform and well shaped Mn3O4 nano-octahedra are synthesized using a simple hydrothermal method under the help of polyethylene glycol (PEG200) as a reductant and shape-directing agent. The nano-octahedra formation mechanism is monitored. The shape and crystal orientation of the nanoparticles is reconstructed by scanning electron microscopy and electron tomography, which reveals that the nano-octahedra only selectively expose {101} facets at the external surfaces. The magnetic testing demonstrates that the Mn3O4 nano-octahedra exhibit anomalous magnetic properties: the Mn3O4 nano-octahedra around 150 nm show a similar Curie temperature and blocking temperature to Mn3O4 nanoparticles with 10 nm size because of the vertical axis of [001] plane and the exposed {101} facets. With these Mn3O4 nano-octahedra as a catalyst, the photodecomposition of rhodamine B is evaluated and it is found that the photodecomposition activity of Mn3O4 nano-octahedra is much superior to that of commercial Mn3O4 powders. The anomalous magnetic properties and high superior photodecomposition activity of well shaped Mn3O4 nano-octahedra should be related to the special shape of the nanoparticles and the abundantly exposed {101} facets at the external surfaces. Therefore, the shape preference can largely broaden the application of the Mn3O4 nano-octahedra. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| Language |
|
Wos |
000288080400008 |
Publication Date |
2011-01-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1613-6810; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
8.643 |
Times cited |
131 |
Open Access |
|
| Notes |
This work was realized in the frame of an Interuniversity Attraction Poles Program (Inanomat-P6/17)-Belgian State-Belgian Science Policy and the project “Redugaz”, financially supported by the European community and the Wallon government in the frame of Interreg IV (France-Wallonie). B. L. S. acknowledges the Chinese Central Government for an “Expert of the State” position in the program of “Thousand talents” and the Chinese Ministry of Education for a Changjiang Scholar position at the Wuhan University of Technology. H. T. acknowledges the financial support from FWO-Vlaanderen (Project nr. G.0147.06). J.V. thanks the financial support from the European Union under Framework 6 program for Integrated Infrastructure Initiative, Reference 026019 ESTEEM. |
Approved |
Most recent IF: 8.643; 2011 IF: 8.349 |
| Call Number |
UA @ lucian @ c:irua:87908 |
Serial |
3914 |
| Permanent link to this record |
| |
|
| |
| Author |
Si, X.-J.; Zhao, S.-X.; Xu, X.; Bogaerts, A.; Wang, Y.-N. |
| Title |
Fluid simulations of frequency effects on nonlinear harmonics in inductively coupled plasma |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Physics of plasmas |
Abbreviated Journal |
Phys Plasmas |
| Volume |
18 |
Issue |
3 |
Pages |
033504-033504,9 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
A fluid model is self-consistently established to investigate the harmonic effects in an inductively coupled plasma, where the electromagnetic field is solved by the finite difference time domain technique. The spatiotemporal distribution of harmonic current density, harmonic potential, and other plasma quantities, such as radio frequency power deposition, plasma density, and electron temperature, have been investigated. Distinct differences in current density have been observed when calculated with and without Lorentz force, which indicates that the nonlinear Lorentz force plays an important role in the harmonic effects, especially at low frequencies. Moreover, the even harmonics are larger than the odd harmonics both in the current density and the potential. Finally, the dependence of various plasma quantities with and without the Lorentz force on various driving frequencies is also examined. It is shown that the deposited power density decreases and the depth of penetration increases slightly because of the Lorentz force. The electron density increases distinctly while the electron temperature remains almost the same when the Lorentz force is taken into account. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Woodbury, N.Y. |
Editor |
|
| Language |
|
Wos |
000289151900073 |
Publication Date |
2011-03-18 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1070-664X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.115 |
Times cited |
7 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.115; 2011 IF: 2.147 |
| Call Number |
UA @ lucian @ c:irua:87876 |
Serial |
1233 |
| Permanent link to this record |
| |
|
| |
| Author |
De Bie, C.; Martens, T.; van Dijk, J.; Paulussen, S.; Verheyde, B.; Corthals, S.; Bogaerts, A. |
| Title |
Dielectric barrier discharges used for the conversion of greenhouse gases: modeling the plasma chemistry by fluid simulations |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
| Volume |
20 |
Issue |
2 |
Pages |
024008,1-024008,11 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
The conversion of methane to value-added chemicals and fuels is considered to be one of the challenges of the 21st century. In this paper we study, by means of fluid modeling, the conversion of methane to higher hydrocarbons or oxygenates by partial oxidation with CO2 or O2 in a dielectric barrier discharge. Sixty-nine different plasma species (electrons, ions, molecules, radicals) are included in the model, as well as a comprehensive set of chemical reactions. The calculation results presented in this paper include the conversion of the reactants and the yields of the reaction products as a function of residence time in the reactor, for different gas mixing ratios. Syngas (i.e. H2 + CO) and higher hydrocarbons (C2Hx) are typically found to be important reaction products. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
| Language |
|
Wos |
000290719900009 |
Publication Date |
2011-04-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.302 |
Times cited |
38 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
| Call Number |
UA @ lucian @ c:irua:87868 |
Serial |
689 |
| Permanent link to this record |
| |
|
| |
| Author |
Yusupov, M.; Bultinck, E.; Depla, D.; Bogaerts, A. |
| Title |
Elucidating the asymmetric behavior of the discharge in a dual magnetron sputter deposition system |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
98 |
Issue |
13 |
Pages |
131502-131502,3 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
A magnetron discharge is characterized by drifts of the charged particles guiding center, caused by the magnetic field, in contrast to unmagnetized discharges. Because of these drifts, a pronounced asymmetry of the discharge can be observed in a dual magnetron setup. In this work, it is found that the shape of the discharge in a dual magnetron configuration depends on the magnetic field configuration. In a closed configuration, strong drifts were observed in one preferential direction, whereas in a mirror configuration the deflection of the discharge was not so pronounced. Our calculations confirm experimental observations. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000289153600017 |
Publication Date |
2011-04-01 |
| 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 |
4 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
| Call Number |
UA @ lucian @ c:irua:87867 |
Serial |
1026 |
| Permanent link to this record |
| |
|
| |
| Author |
Biermans, E.; Molina, L.; Batenburg, K.J.; Bals, S.; Van Tendeloo, G. |
| Title |
Measuring porosity at the nanoscale by quantitative electron tomography |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
| Volume |
10 |
Issue |
12 |
Pages |
5014-5019 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
| Abstract |
Quantitative electron tomography is proposed to characterize porous materials at a nanoscale. To achieve reliable three-dimensional (3D) quantitative information, the influence of missing wedge artifacts and segmentation methods is investigated. We are presenting the Discrete Algebraic Reconstruction Algorithm as the most adequate tomography method to measure porosity at the nanoscale. It provides accurate 3D quantitative information, regardless the presence of a missing wedge. As an example, we applied our approach to nanovoids in La2Zr2O7 thin films. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington |
Editor |
|
| Language |
|
Wos |
000284990900040 |
Publication Date |
2010-11-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.712 |
Times cited |
79 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: 12.712; 2010 IF: 12.219 |
| Call Number |
UA @ lucian @ c:irua:87658 |
Serial |
1967 |
| Permanent link to this record |
| |
|
| |
| Author |
Eckert, M.; Mortet, V.; Zhang, L.; Neyts, E.; Verbeeck, J.; Haenen, ken; Bogaerts, A. |
| Title |
Theoretical investigation of grain size tuning during prolonged bias-enhanced nucleation |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
23 |
Issue |
6 |
Pages |
1414-1423 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
In this paper, the effects of prolonged bias-enhanced nucleation (prolonged BEN) on the growth mechanisms of diamond are investigated by molecular dynamics (MD) and combined MD-Metropolis Monte Carlo (MD-MMC) simulations. First, cumulative impacts of CxHy+ and Hx+ on an a-C:H/nanodiamond composite were simulated; second, nonconsecutive impacts of the dominant ions were simulated in order to understand the observed phenomena in more detail. As stated in the existing literature, the growth of diamond structures during prolonged BEN is a process that takes place below the surface of the growing film. The investigation of the penetration behavior of CxHy+ and Hx+ species shows that the carbon-containing ions remain trapped within this amorphous phase where they dominate mechanisms like precipitation of sp3 carbon clusters. The H+ ions, however, penetrate into the crystalline phase at high bias voltages (>100 V), destroying the perfect diamond structure. The experimentally measured reduction of grain sizes at high bias voltage, reported in the literature, might thus be related to penetrating H+ ions. Furthermore, the CxHy+ ions are found to be the most efficient sputtering agents, preventing the build up of defective material. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000288291400011 |
Publication Date |
2011-02-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
9.466 |
Times cited |
9 |
Open Access |
|
| Notes |
Iwt; Fwo; Esteem 026019; Iap |
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
| Call Number |
UA @ lucian @ c:irua:87642 |
Serial |
3605 |
| Permanent link to this record |
| |
|
| |
| Author |
Ustarroz, J.; Gupta, U.; Hubin, A.; Bals, S.; Terryn, H. |
| Title |
Electrodeposition of Ag nanoparticles onto carbon coated TEM grids : a direct approach to study early stages of nucleation |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Electrochemistry communications |
Abbreviated Journal |
Electrochem Commun |
| Volume |
12 |
Issue |
12 |
Pages |
1706-1709 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
An innovative experimental approach to study the electrodeposition of small nanoparticles and the early stages of electrochemical nucleation and growth is presented. Carbon coated gold TEM grids are used as substrates for the electrodeposition of silver nanoparticles so that electrochemical data, FESEM, HAADFSTEM and HRTEM data can be acquired from the same sample without the need to remove the particles from the substrate. It is shown that the real distribution of nanoparticles cannot be resolved by FESEM whereas HAADFSTEM analysis confirms that a distribution of small nanoparticles (d ≈ 12 nm) coexist with large nanoparticles corresponding to a bimodal size distribution. Besides, particles grown under the same conditions have been found to present different structures such as monocrystals, polycrystals or aggregates of smaller particles. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000285904700010 |
Publication Date |
2010-10-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1388-2481; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.396 |
Times cited |
52 |
Open Access |
|
| Notes |
Fwo |
Approved |
Most recent IF: 4.396; 2010 IF: 4.287 |
| Call Number |
UA @ lucian @ c:irua:87612 |
Serial |
900 |
| Permanent link to this record |
| |
|
| |
| Author |
Heidari Mezerji, H.; van den Broek, W.; Bals, S. |
| Title |
A practical method to determine the effective resolution in incoherent experimental electron tomography |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| Volume |
111 |
Issue |
5 |
Pages |
330-336 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
| Abstract |
It is not straightforward to determine resolution for a 3D reconstruction when performing an electron tomography experiment. Different contributions such as missing wedge and misalignment add up and often influence the final resolution in an anisotropic manner. The conventional resolution measures can not be used for all of the reconstruction techniques, especially for iterative techniques which are more commonly used for electron tomography in materials science. Here we define a quantitative resolution measure that determines the resolution in three orthogonal directions of the reconstruction. As an application we use this measure to determine the optimum number of simultaneous iterative reconstruction technique (SIRT) iterations to reconstruct the gold nanoparticles, based on a high angle annular dark field STEM (HAADF-STEM) tilt series. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000289396900005 |
Publication Date |
2011-01-24 |
| 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 |
26 |
Open Access |
|
| Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
| Call Number |
UA @ lucian @ c:irua:87606 |
Serial |
2688 |
| Permanent link to this record |
| |
|
| |
| Author |
Croitoru, M.D.; van Dyck, D.; Van Aert, S.; Bals, S.; Verbeeck, J. |
| Title |
An efficient way of including thermal diffuse scattering in simulation of scanning transmission electron microscopic images |
Type |
A1 Journal article |
| Year |
2006 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| Volume |
106 |
Issue |
10 |
Pages |
933-940 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Vision lab |
| Abstract |
We propose an improved image simulation procedure for atomic-resolution annular dark-field scanning transmission electron microscopy (STEM) based on the multislice formulation, which takes thermal diffuse scattering fully into account. The improvement with regard to the classical frozen phonon approach is realized by separating the lattice configuration statistics from the dynamical scattering so as to avoid repetitive calculations. As an example, the influence of phonon scattering on the image contrast is calculated and investigated. STEM image simulation of crystals can be applied with reasonable computing times to problems involving a large number of atoms and thick or large supercells. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000240397200006 |
Publication Date |
2006-05-10 |
| 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 |
18 |
Open Access |
|
| Notes |
Fwo; Fwo-V |
Approved |
Most recent IF: 2.843; 2006 IF: 1.706 |
| Call Number |
UA @ lucian @ c:irua:87604UA @ admin @ c:irua:87604 |
Serial |
876 |
| Permanent link to this record |
| |
|
| |
| Author |
Bals, S.; Radmilovic, V.; Kisielowski, C. |
| Title |
TEM annular objective apertures fabricated by FIB |
Type |
A1 Journal article |
| Year |
2004 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
| Volume |
10 |
Issue |
S:2 |
Pages |
1148-1149 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge, Mass. |
Editor |
|
| Language |
|
Wos |
|
Publication Date |
2008-01-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record |
| Impact Factor |
1.891 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.891; 2004 IF: 2.389 |
| Call Number |
UA @ lucian @ c:irua:87603 |
Serial |
3475 |
| Permanent link to this record |
| |
|
| |
| Author |
Aerts, A.; Follens, L.R.A.; Biermans, E.; Bals, S.; Van Tendeloo, G.; Loppinet, B.; Kirschhock, C.E.A.; Martens, J.A. |
| Title |
Modelling of synchrotron SAXS patterns of silicalite-1 zeolite during crystallization |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
13 |
Issue |
10 |
Pages |
4318-4325 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Synchrotron small angle X-ray scattering (SAXS) was used to characterize silicalite-1 zeolite crystallization from TEOS/TPAOH/water clear sol. SAXS patterns were recorded over a broad range of length scales, enabling the simultaneous monitoring of nanoparticles and crystals occurring at various stages of the synthesis. A simple two-population model accurately described the patterns. Nanoparticles were modeled by polydisperse coreshell spheres and crystals by monodisperse oblate ellipsoids. These models were consistent with TEM images. The SAXS results, in conjunction with in situ light scattering, showed that nucleation of crystals occurred in a short period of time. Crystals were uniform in size and shape and became increasingly anisotropic during growth. In the presence of nanoparticles, crystal growth was fast. During crystal growth, the number of nanoparticles decreased gradually but their size was constant. These observations suggested that the nanoparticles were growth units in an aggregative crystal growth mechanism. Crystals grown in the presence of nanoparticles developed a faceted habit and intergrowths. In the final stages of growth, nanoparticles were depleted. Concurrently, the crystal growth rate decreased significantly. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000287584700017 |
Publication Date |
2011-01-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.123 |
Times cited |
22 |
Open Access |
|
| Notes |
Fwo; Iap; Esteem 026019 |
Approved |
Most recent IF: 4.123; 2011 IF: 3.573 |
| Call Number |
UA @ lucian @ c:irua:87602 |
Serial |
2155 |
| Permanent link to this record |
| |
|
| |
| Author |
Jinschek, J.R.; Bals, S.; Gopal, V.; Xus, X.; Kisielowski, C. |
| Title |
Probing local stoichiometry in InGaN based quantum wells of solid-state LEDs |
Type |
A3 Journal article |
| Year |
2004 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
| Volume |
10 |
Issue |
S:2 |
Pages |
294-295 |
| Keywords |
A3 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
|
Publication Date |
2008-01-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record |
| Impact Factor |
1.891 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.891; 2004 IF: 2.389 |
| Call Number |
UA @ lucian @ c:irua:87599 |
Serial |
2714 |
| Permanent link to this record |
| |
|
| |
| Author |
Lubyshev, D.; Fastenau, J.M.; Fang, X.-M.; Wu, Y.; Doss, C.; Snyder, A.; Liu, W.K.; Lamb, M.S.M.; Bals, S.; Song, C. |
| Title |
Comparison of As- and P-based metamorphic buffers for high performance InP heterojunction bipolar transistor and high electron mobility transistor applications |
Type |
A1 Journal article |
| Year |
2004 |
Publication |
Journal of vacuum science & technology. B. Microelectronics and nanometer structures. Processing, measurement and phenomena |
Abbreviated Journal |
|
| Volume |
22 |
Issue |
3 |
Pages |
1565-1569 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Metamorphic buffers (M-buffers) consisting of graded InAlAs or bulk InP were employed for the production of InP-based epiwafers on GaAs substrates by molecular-beam epitaxy. The graded InAlAs is the standard for production metamorphic high electron mobility transistors (M-HEMTs), while the bulk InP offers superior thermal properties for higher current density circuits. The surface morphology and crystal structure of the two M-buffers showed different relaxation mechanisms. The graded InAlAs gave a cross-hatched pattern with nearly full relaxation and very effective dislocation filtering, while the bulk InP had a uniform isotropic surface with dislocations propagating further up towards the active layers. Both types of M-buffers had atomic force microscopy root-mean-square roughness values around 2030 Å. The Hall transport properties of high electron mobility transistors (HEMTs) grown on the InAlAs M-buffer, and a baseline HEMT grown lattice matched on InP, both had room-temperature mobilities >10 000 cm2/V s, while the M-HEMT on the InP M-buffer showed a decrease to 9000 cm2/V s. Similarly, the dc parameters of a double heterojunction bipolar transistor (DHBT) grown on the InAlAs M-buffer were much closer to the baseline heterojunction bipolar transistor than a DHBT grown on the InP M-buffer. A high breakdown voltage of 11.3 V was achieved on an M-DHBT with the InAlAs M-buffer. We speculate that the degradation in device characteristics on the InP M-buffer was related to the incomplete dislocation filtering. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Woodbury, N.Y. |
Editor |
|
| Language |
|
Wos |
000222481400141 |
Publication Date |
2004-07-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0734-211X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
25 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:87596 |
Serial |
427 |
| Permanent link to this record |
| |
|
| |
| Author |
Gottschalck Andersen, L.; Bals, S.; Van Tendeloo, G.; Poulsen, H.F.; Liu, Y.L. |
| Title |
Transmission electron microscopy investigation of Bi-2223/Ag tapes |
Type |
A1 Journal article |
| Year |
2001 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
| Volume |
353 |
Issue |
3/4 |
Pages |
251-257 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The microstructure of (Bi,Pb)2Sr2Ca2Cu3Ox (Bi-2223) tapes has been investigated by means of transmission electron microscopy (TEM) and high-resolution TEM. The emphasis has been placed on: (1) an examination of the grain morphology and size, (2) grain and colony boundary angles, which are formed during the tape processing, (3) a study of the grain boundaries on an atomic scale, including intergrowth investigations. Tapes with different process parameters have been compared with respect to the microstructure. A fully processed tape has on the average 50% thicker Bi-2223 grains than a tape after the first annealing. The angles of c-axis tilt grain boundaries are on average 14° and 26° for the fully processed tape and the tape after the first annealing, respectively. The intergrowth content (15%) and distribution are similar in these two tapes. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000168861100012 |
Publication Date |
2002-07-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.404 |
Times cited |
13 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.404; 2001 IF: 0.806 |
| Call Number |
UA @ lucian @ c:irua:87591 |
Serial |
3708 |
| Permanent link to this record |
| |
|
| |
| Author |
Salluzzo, M.; Aruta, C.; Maggio-Aprile, I.; Fischer, Ø.; Bals, S.; Zegenhagen, J. |
| Title |
Growth of R1+xBa2-xCu3O7-\delta epitaxial films investigated by in situ scanning tunneling microscopy |
Type |
A1 Journal article |
| Year |
2001 |
Publication |
Physica status solidi: A: applied research |
Abbreviated Journal |
Phys Status Solidi A |
| Volume |
186 |
Issue |
3 |
Pages |
339-364 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The problem of the epitaxial growth of the high temperature superconducting R1+xBa2xCu3O7δ (R = Y or rare earth except Ce and Tb) films has been addressed. Using in situ ultra high vacuum Scanning Tunneling Microscopy (UHV-STM) we have studied the role of cationic substitution and substrate mismatch on the growth mode of stoichiometric and Nd-rich Nd1+xBa2xCu3O7δ thin films. The results are compared to the growth of Y1Ba2Cu3O7δ, Dy1Ba2Cu3O7δ and Gd1Ba2Cu3O7δ epitaxial films. Two main phenomena are investigated: a) the first stage of the direct nucleation on the substrate and b) the crossover between 2D and 3D growth upon increasing the film thickness. At the first stage of the growth, pseudo-cubic perovskite (Re,Ba)CuO3 nuclei are formed. While they disappear after the growth of a few nm in stoichiometric films, they persist on the surface of Nd-rich films of up to 110 nm thickness. Stoichiometric R1+xBa2xCu3O7δ films exhibit a rough morphology with increasing thickness due to island growth mode, whereas Nd-rich films remain smooth and continue to grow layer by layer. It is proposed that linear defects (like anti-phase boundaries), which are formed due to the misalignment of growth fronts, are the source of screw dislocations in stoichiometric films. In Nd-rich films, linear defects are eliminated through the insertion of (Nd,Ba)CuO3 extra layers without introduction of any screw dislocations. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Berlin |
Editor |
|
| Language |
|
Wos |
000170844500002 |
Publication Date |
2004-11-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-8965;1521-396X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
17 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:87587 |
Serial |
1398 |
| Permanent link to this record |
| |
|
| |
| Author |
Bals, S.; Kabius, B.; Haider, M.; Radmilovic, V.; Kisielowski, C. |
| Title |
Annular dark field imaging in a TEM |
Type |
A1 Journal article |
| Year |
2004 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
| Volume |
130 |
Issue |
10 |
Pages |
675-680 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Annular objective apertures are fabricated for a CM300 transmission electron microscope using a focused ion beam system. A central beam stop in the back focal plane of the objective lens of the microscope blocks all electrons scattered up to a semi-angle of approximately 20 mrad. In this manner, contributions to the image from Bragg scattering are largely reduced and the image contrast is sensitive to the atomic number Z. Experimentally, we find that single atom scattering cross sections measured with this technique are close to Rutherford scattering values. A comparison between this new method and STEM-HAADF shows that both techniques result in qualitatively similar images although the resolution of ADF-TEM is limited by contrast delocalization caused by the spherical aberration of the objective lens. This problem can be overcome by using an aberration corrected microscope. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000221489300007 |
Publication Date |
2004-04-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0038-1098; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.554 |
Times cited |
43 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.554; 2004 IF: 1.523 |
| Call Number |
UA @ lucian @ c:irua:87584 |
Serial |
132 |
| Permanent link to this record |
| |
|
| |
| Author |
Yusupov, M.; Bultinck, E.; Depla, D.; Bogaerts, A. |
| Title |
Behavior of electrons in a dual-magnetron sputter deposition system : a Monte Carlo model |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
| Volume |
13 |
Issue |
|
Pages |
033018-033018,17 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
A Monte Carlo model has been developed for investigating the electron behavior in a dual-magnetron sputter deposition system. To describe the three-dimensional (3D) geometry, different reference frames, i.e. a local and a global coordinate system, were used. In this study, the influence of both closed and mirror magnetic field configurations on the plasma properties is investigated. In the case of a closed magnetic field configuration, the calculated electron trajectories show that if an electron is emitted in (or near) the center of the cathode, where the influence of the magnetic field is low, it is able to travel from one magnetron to the other. On the other hand, when an electron is created at the race track area, it is more or less trapped in the strong magnetic field and cannot easily escape to the second magnetron region. In the case of a mirror magnetic field configuration, irrespective of where the electron is emitted from the cathode, it cannot travel from one magnetron to the other because the magnetic field lines guide the electron to the substrate. Moreover, the electron density and electron impact ionization rate have been calculated and studied in detail for both configurations. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Bristol |
Editor |
|
| Language |
|
Wos |
000289064600001 |
Publication Date |
2011-03-15 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.786 |
Times cited |
12 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.786; 2011 IF: 4.177 |
| Call Number |
UA @ lucian @ c:irua:87544 |
Serial |
224 |
| Permanent link to this record |
| |
|
| |
| Author |
Simon, P.; Bogaerts, A. |
| Title |
Vibrational level population of nitrogen impurities in low-pressure argon glow discharges |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
| Volume |
26 |
Issue |
4 |
Pages |
804-810 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
The vibrational level populations of the electronic ground state of the nitrogen molecule have been calculated for typical glow discharge conditions in argonnitrogen mixtures with nitrogen concentrations between 0.1 and 1%. Stationary solutions of the master equations of the vibrational levels have been obtained using numerical methods. The main mechanisms responsible for the population and depopulation of the vibrational levels, and for the overall shape of the vibrational distribution function are pointed out. It has been found that vibrationvibration collisions play only a minor role and therefore the population of the vibrational levels is basically determined by the electron temperature. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000288703300012 |
Publication Date |
2010-12-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0267-9477;1364-5544; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.379 |
Times cited |
6 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.379; 2011 IF: 3.220 |
| Call Number |
UA @ lucian @ c:irua:87530 |
Serial |
3842 |
| Permanent link to this record |
| |
|
| |
| Author |
Van Grieken, R.; Worobiec, A. |
| Title |
X-ray spectrometry for preventive conservation of cultural heritage |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Pramåna: a journal of physics |
Abbreviated Journal |
|
| Volume |
72 |
Issue |
2 |
Pages |
191-200 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) |
| Abstract |
Analytical chemistry does play a key role in the chemical characterization of the environment and it appears that X-ray spectrometry, in its many forms, is one of the most relevant analytical techniques in preventive conservation, as it is in cultural heritage research in general. X-ray spectrometry has indeed been the method of choice for the characterization of the inorganic composition of atmospheric aerosols, for a long time. We have, over the last decade, intensively used various forms of X-ray spectrometry, viz., mostly energy-dispersive X-ray fluorescence, e.g. with polarized high-energy beam excitation, and automated electron probe X-ray microanalysis, together with other techniques, to identify particle types and their sources in indoor environments, including museums, while gaseous indoor pollutants were assessed using passive diffusion samplers. In each case, both bulk aerosols and individual aerosol particles were studied. For microanalysis of single particles, we have investigated a dozen techniques, but for wide, real-life applications, automated electron probe X-ray microanalysis is the most rewarding. We have first studied atmospheric aerosols in and around the Correr Museum in Venice, many other museums in Austria, Japan and England, and in the caves with prehistoric rock paintings in Altamira, Spain. Very recently, measurements were done in the Metropolitan Museum of Art in New York and theWawel Castle in Cracow, in Italian and Polish mountain churches, in a number of museums in Belgium and the Netherlands, and in cathedrals with medieval stained glass windows. In the Correr museum, it appeared that the particles most threatening for the Bellini paintings were released by the deteriorating plaster renderings, and this could be avoided by simply improving the rendering on the museum walls. In the Wawel Castle, outdoor pollution particles, like fine soot from diesel traffic, entering via leaks in the windows and doors, and also street-deicing salts and coal burning pollution particles, brought in by visitors, mostly in winter, were found to be most worrisome. Urgent questions that are not solved at this moment pertain to the deposition processes from the atmosphere to the cultural heritage items, the critical surface interactions that take place on these items, and the establishment of suitable particle concentration standards. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000288861000002 |
Publication Date |
2011-05-20 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0304-4289; 0973-7111 |
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:87025 |
Serial |
8785 |
| Permanent link to this record |
| |
|
| |
| Author |
Potgieter-Vermaak, S.; Maledi, N.; Wagner, N.; van Heerden, J.H.P.; Van Grieken, R.; Potgieter, J.H. |
| Title |
Raman spectroscopy for the analysis of coal : a review |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of Raman spectroscopy |
Abbreviated Journal |
|
| Volume |
42 |
Issue |
2 |
Pages |
123-129 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
The advances in the characterization of amorphous carbons by Raman spectroscopy over the last four decades are of interest to many industries, especially those involving the combustion, gasification and pyrolysis of coal. Many researchers report on the Raman character of the natural organic matter in carbon-containing compounds, such as coal, and relate the Raman bands to the structural order of the amorphous carbons. The basis of most of these studies evolved around the assignment of the G (graphitic, ∼1580 cm−1) band to crystalline graphite and any other bands, called D bands, (disorder, various from 1100 to 1500 cm−1) to any type of structural disorder in the graphitic structure. Concerning coal analysis, the information gained by Raman investigations has been used to describe char evolution as a function of temperature, the presence of catalysts and different gasification conditions. In addition, researchers looked at maturation, grade, doppleritization and many more aspects of interest. One aspect that has, however, not been addressed by most of the researchers is the natural inorganic matter (NIM) in the carbon-containing compounds. Micro-Raman spectroscopy (MRS) has many advantages over other characterization tools, i.e. in situ analysis, nondestructive, no sample preparation, low detection limit, micrometer-scale characterization, versatility and sensitivity to many amorphous compounds. With the distinct advantages it has over that of other molecular characterization tools, such as powder X-ray diffraction (PXRD), Fourier-transform infrared spectrometry (FT-IR) and scanning electron microscopy with X-ray detection (SEM/EDS), it is surprising that it has not yet been fully exploited up to this point for the characterization of the NIM in coal and other amorphous carbons. This paper reviews the work published on the Raman characterization of the natural organic matter (NOM) of coals and reports on preliminary results of the NIM character of various South African coals, whereby various inorganic compounds and minerals in the coal have been characterized. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000288543000001 |
Publication Date |
2010-03-11 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0377-0486 |
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:87024 |
Serial |
8452 |
| Permanent link to this record |
| |
|
| |
| Author |
Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. |
| Title |
Stability and structures of the \epsilon-phases of iron nitrides and iron carbides from first principles |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
| Volume |
64 |
Issue |
3 |
Pages |
296-299 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
First-principles calculations were performed for the ε-phases and other iron carbides/nitrides with hexagonal close-packed Fe sublattices. Although these nitrides/carbides have similar crystal structures, they exhibit different chemical and physical properties. Relative to α-Fe, graphite and N2, all the ε-type nitrides are stable, while all the carbides are metastable. The lattice parameters of the ε-iron nitrides vary differently from those of the ε-carbides, as a function of the concentration of X (Xdouble bond; length as m-dashN, C). The structural relationships of ε-Fe2X with η-Fe2X and ζ-Fe2X are discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| Language |
|
Wos |
000285323300022 |
Publication Date |
2010-09-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.747 |
Times cited |
29 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.747; 2011 IF: 2.699 |
| Call Number |
UA @ lucian @ c:irua:86974 |
Serial |
3120 |
| Permanent link to this record |
| |
|
| |
| Author |
Ao, Z.M.; Hernández-Nieves, A.D.; Peeters, F.M.; Li, S. |
| Title |
Enhanced stability of hydrogen atoms at the graphene/graphane interface of nanoribbons |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
97 |
Issue |
23 |
Pages |
233109,1-233109,3 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The thermal stability of graphene/graphane nanoribbons (GGNRs) is investigated using density functional theory. It is found that the energy barriers for the diffusion of hydrogen atoms on the zigzag and armchair interfaces of GGNRs are 2.86 and 3.17 eV, respectively, while the diffusion barrier of an isolated H atom on pristine graphene was only ∼ 0.3 eV. These results unambiguously demonstrate that the thermal stability of GGNRs can be enhanced significantly by increasing the hydrogen diffusion barriers through graphene/graphane interface engineering. This may provide new insights for viable applications of GGNRs. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000285364000067 |
Publication Date |
2010-12-11 |
| 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 |
43 |
Open Access |
|
| Notes |
; The financial supports by the Vice-Chancellor's Postdoctoral Research Fellowship Program of the University of New South Wales (SIR50/PS19184), the Flemish Science Foundation (FWO-VI), and the Belgian Science Policy (IAP) are acknowledged. A.D.H. acknowledges also support from ANPCyT (Grant No. PICT2008-2236) and the collaborative project FWO-MINCyT (FW/08/01). ; |
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
| Call Number |
UA @ lucian @ c:irua:86972 |
Serial |
1056 |
| Permanent link to this record |
| |
|
| |
| Author |
Austing, D.G.; Payette, C.; Nair, S.V.; Yu, G.; Gupta, J.A.; Partoens, B.; Amaha, S.; Tarucha, S. |
| Title |
Scheme for coherently quenching resonant current in a three-level quantum dot energy level mixer |
Type |
A1 Journal article |
| Year |
2009 |
Publication |
Physica status solidi: C: conferences and critical reviews |
Abbreviated Journal |
|
| Volume |
6 |
Issue |
4 |
Pages |
940-943 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We outline a scheme to create a dark state by three-level mixing that is potentially a useful tool for quantum coherent transport. Magnetic-field-induced intra-dot level mixing can lead to rich quantum superposition phenomena between three approaching single-particle states in a quantum dot when probed by the ground state of an adjacent weakly coupled quantum dot in the single-electron resonant tunnelling regime. The mixing relies on non-negligible anharmonicity and anisotropy in confining potentials of realistic quantum dots. Anti-crossing and transfer of strengths between resonances can be understood with a simple coherent level mixing model. Superposition can lead to the formation of a dark state by complete cancellation of an otherwise strong resonance. This is an all-electrical analogue of coherent population trapping seen in three-level-systems from quantum and atom optics. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Berlin |
Editor |
|
| Language |
|
Wos |
000266597600040 |
Publication Date |
2008-12-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1862-6351;1610-1642; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:86927 |
Serial |
2953 |
| Permanent link to this record |
