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Records |
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Author |
Li, M.R.; Retuerto, M.; Bok Go, Y.; Emge, T.J.; Croft, M.; Ignatov, A.; Ramanujachary, K.V.; Dachraoui, W.; Hadermann, J.; Tang, M.B.; Zhao, J.T.; Greenblatt, M.; |
| |
Title |
Synthesis, crystal structure, and properties of KSbO3-type Bi3Mn1.9Te1.1O11 |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| |
Volume |
197 |
Issue |
|
Pages |
543-549 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Single crystals of Bi3Mn1.9Te1.1O11 were prepared from NaCl+KCl flux. This compound adopts KSbO3-type crystal structure as evidenced by electron and single crystal X-ray diffraction analysis. The three-dimensional channel structure is formed by corner-sharing octahedral (Mn0.63Te0.37)2O10 dimers and two identical (Bi1)4(Bi2)2 interpenetrating lattices. The intra-dimer Mn/TeMn/Te distances in Bi3Mn1.9Te1.1O11 are short and are consistent with weak metalmetal interactions. The mixed oxidation state of manganese and the edge-sharing octahedral features are confirmed by X-ray near edge absorption spectroscopy measurements, which indicate Bi3(MnIII1.1MnIV0.8)TeVI1.1O11 with 57.7% Mn3+ and 42.3% Mn4+. The partial substitution of Te for Mn perturbs long-range magnetic interactions, thereby destroying the ferromagnetic ordering found in Bi3Mn3O11 (TC=150 K). |
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Address |
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Corporate Author |
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Thesis |
|
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Publisher |
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Place of Publication |
London |
Editor |
|
| |
Language |
|
Wos |
000312281000076 |
Publication Date  |
2012-07-25 |
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Series Editor |
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Series Title |
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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 |
13 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.299; 2013 IF: 2.200 |
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Call Number |
UA @ lucian @ c:irua:101779 |
Serial |
3452 |
| Permanent link to this record |
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|
| |
|
Author |
Anaf, W.; Horemans, B.; Madeira, T.I.; Carvalho, M.L.; De Wael, K.; Van Grieken, R. |
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Title |
Effects of a constructional intervention on airborne and deposited particulate matter in the Portuguese National Tile Museum, Lisbon |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Environmental Science and Pollution Research |
Abbreviated Journal |
Environ Sci Pollut R |
| |
Volume |
20 |
Issue |
3 |
Pages |
1849-1857 |
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| |
Abstract |
In the 1970s, a large ambulatory of the National Tile Museum, Lisbon, was closed with glass panes on both ground and first floor. Although this design was meant to protect the museum collection from ambient air pollutants, small openings between the glass panes remain, creating a semi-enclosed corridor. The effects of the glass panes on the indoor air quality were evaluated in a comparative study by monitoring the airborne particle concentration and the extent of particle deposition at the enclosed corridor as well as inside the museum building. Comparison of the indoor/outdoor ratio of airborne particle concentration demonstrated a high natural ventilation rate in the enclosed corridor as well as inside the museum building. PM10 deposition velocities on vertical surfaces were estimated in the order of 3 × 10−4 m s−1 for both indoor locations. Also, the deposition rates of dark-coloured and black particles in specific were very similar at both indoor locations, causing visual degradation. The effectiveness of the glass panes in protecting the museum collection is discussed. |
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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 |
000315442500061 |
Publication Date |
2012-07-24 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0944-1344; 1614-7499 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.741 |
Times cited |
15 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 2.741; 2013 IF: 2.757 |
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Call Number |
UA @ admin @ c:irua:100214 |
Serial |
5583 |
| Permanent link to this record |
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|
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Author |
Costamagna, S.; Neek-Amal, M.; Los, J.H.; Peeters, F.M. |
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Title |
Thermal rippling behavior of graphane |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
86 |
Issue |
4 |
Pages |
041408-4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Thermal fluctuations of single layer hydrogenated graphene (graphane) are investigated using large scale atomistic simulations. By analyzing the mean square value of the height fluctuations < h(2)> and the height-height correlation function H(q) for different system sizes and temperatures, we show that hydrogenated graphene is an unrippled system in contrast to graphene. The height fluctuations are bounded, which is confirmed by a H(q) tending to a constant in the long wavelength limit instead of showing the characteristic scaling law q(4-eta)(eta similar or equal to 0.85) predicted by membrane theory. This unexpected behavior persists up to temperatures of at least 900 K and is a consequence of the fact that in graphane the thermal energy can be accommodated by in-plane bending modes, i.e., modes involving C-C-C bond angles in the buckled carbon layer, instead of leading to significant out-of-plane fluctuations that occur in graphene. |
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Address |
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
| |
Language |
|
Wos |
000306649200002 |
Publication Date |
2012-07-23 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
46 |
Open Access |
|
| |
Notes |
; We thank A. Fasolino, A. Dobry, and K. H. Michel for their useful comments. S.C. is supported by the Belgian Science Foundation (BELSPO). This work is supported by the ESF-EuroGRAPHENE project CONGRAN and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:100840 |
Serial |
3630 |
| Permanent link to this record |
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|
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Author |
Yusupov, M.; Saraiva, M.; Depla, D.; Bogaerts, A. |
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Title |
Sputter deposition of MgxAlyOz thin films in a dual-magnetron device : a multi-species Monte Carlo model |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
| |
Volume |
14 |
Issue |
7 |
Pages |
073043 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A multi-species Monte Carlo (MC) model, combined with an analytical surface model, has been developed in order to investigate the general plasma processes occurring during the sputter deposition of complex oxide films in a dual-magnetron sputter deposition system. The important plasma species, such as electrons, Ar+ ions, fast Ar atoms and sputtered metal atoms (i.e. Mg and Al atoms) are described with the so-called multi-species MC model, whereas the deposition of MgxAlyOz films is treated by an analytical surface model. Targetsubstrate distances for both magnetrons in the dual-magnetron setup are varied for the purpose of growing stoichiometric complex oxide thin films. The metal atoms are sputtered from pure metallic targets, whereas the oxygen flux is only directed toward the substrate and is high enough to obtain fully oxidized thin films but low enough to avoid target poisoning. The calculations correspond to typical experimental conditions applied to grow these complex oxide films. In this paper, some calculation results are shown, such as the densities of various plasma species, their fluxes toward the targets and substrate, the deposition rates, as well as the film stoichiometry. Moreover, some results of the combined model are compared with experimental observations. Note that this is the first complete model, which can be applied for large and complicated magnetron reactor geometries, such as dual-magnetron configurations. With this model, we are able to describe all important plasma species as well as the deposition process. It can also be used to predict film stoichiometries of complex oxide films on the substrate. |
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Address |
|
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Corporate Author |
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Thesis |
|
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Publisher |
|
Place of Publication |
Bristol |
Editor |
|
| |
Language |
|
Wos |
000307072500003 |
Publication Date |
2012-07-21 |
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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 |
2 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.786; 2012 IF: 4.063 |
| |
Call Number |
UA @ lucian @ c:irua:100100 |
Serial |
3111 |
| Permanent link to this record |
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|
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Author |
Neek-Amal, M.; Covaci, L.; Peeters, F.M. |
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Title |
Nanoengineered nonuniform strain in graphene using nanopillars |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
86 |
Issue |
4 |
Pages |
041405 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Recent experiments showed that nonuniform strain can be produced by depositing graphene over pillars. We employed atomistic calculations to study the nonuniform strain and the induced pseudomagnetic field in graphene on top of nanopillars. By decreasing the distance between the nanopillars a complex distribution for the pseudomagnetic field can be generated. Furthermore, we performed tight-binding calculations of the local density of states (LDOS) by using the relaxed graphene configuration obtained from atomistic calculations. We find that the quasiparticle LDOS are strongly modified near the pillars, both at low energies showing sublattice polarization and at high energies showing shifts of the van Hove singularity. Our study shows that changing the specific pattern of the nanopillars allows us to create a desired shape of the pseudomagnetic field profile while the LDOS maps provide an input for experimental verification by scanning tunneling microscopy. |
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Address |
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Corporate Author |
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Thesis |
|
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
| |
Language |
|
Wos |
000306313900001 |
Publication Date |
2012-07-14 |
| |
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 |
51 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-V1) and the EuroGRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:100765 |
Serial |
2255 |
| Permanent link to this record |
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Author |
Pina, J.C.; de Souza Silva, C.C.; Milošević, M.V. |
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Title |
Stability of fractional vortex states in a two-band mesoscopic superconductor |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
86 |
Issue |
2 |
Pages |
024512 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate the stability of noncomposite fractional vortex states in a mesoscopic two-band superconductor within the two-component Ginzburg-Landau model. Our analysis explicitly takes into account the relationship between the model parameters and microscopic material parameters, such as partial density of states, Fermi velocities and elements of the electron-phonon coupling matrix. We have found that states with different phase winding number in each band (L-1 not equal L-2) and fractional flux can exist in many different configurations, including rather unconventional ones where the dominating band carries larger winding number and states where vertical bar L-1 – L-2 vertical bar > 1. We present a detailed analysis of the stability of the observed vortex structures with respect to changing the microscopic parameters, showing that, in the weak coupling case, fractional vortex states can be assessed in essentially the whole range of temperatures and applied magnetic fields in which both bands are active. Finally, we propose an efficient way of increasing the range of parameters for which these fractional vortex states can be stabilized. In particular, our proposal allows for observation of fractional vortex structures in materials with stronger coupling, where those states are forbidden at a homogeneous field. This is accomplished with the help of the stray fields of a suitably prepared magnetic dot placed nearby the superconducting disk. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
|
| |
Language |
|
Wos |
000306309600006 |
Publication Date |
2012-07-14 |
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Series Editor |
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Series Title |
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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 |
38 |
Open Access |
|
| |
Notes |
; We thank Eric B. Claude, Miguel A. Zorro, and Rogerio M. da Silva for assistance in the development of the numerical code used in our simulations. This work was supported by the Brazilian science agencies CNPq and FACEPE, by the FACEPE/CNPq-PRONEX program, under Grant No. APQ-0589-1.05/08, and by CNPq-FWO Brazil-Flanders co-operation program. M.V.M. acknowledges support from the CAPES-PVE program. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:100766 |
Serial |
3126 |
| Permanent link to this record |
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Author |
Tirry, W.; Bouvier, S.; Benmhenni, N.; Hammami, W.; Habraken, A.M.; Coghe, F.; Schryvers, D.; Rabet, L. |
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Title |
Twinning in pure Ti subjected to monotonic simple shear deformation |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Materials characterization |
Abbreviated Journal |
Mater Charact |
| |
Volume |
72 |
Issue |
|
Pages |
24-36 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The aim of this paper is to provide a thorough study on the occurrence and importance of deformation twinning in simple shear deformed pure α-Ti. A statistically relevant inspection of the morphology of the deformation twins in relation to the applied strain/deformation is performed. The investigated microstructural aspects are the twin volume fraction, the twin thickness distribution and the resolved shear stress distribution on the twin plane. All these aspects are examined as a function of the twin types and two initial textures. Monotonic simple shear experiments are carried out for three different loading directions with respect to a direction linked to the initial crystallographic texture. EBSD and TEM observations reveal the presence of View the MathML source and View the MathML source twins. The statistical analysis reveals that View the MathML source and View the MathML source twins have a similar average thickness around 1.9 nm, but the View the MathML source twins show a far larger spread on their thickness and can grow to almost the size of the original parent grain. Correlation of the twin fractions with the RSS analysis shows that RSS is an acceptable method explaining the difference in twin fractions for different textures and orientations. A detailed analysis shows that View the MathML source twins occur in average with a smaller volume fraction but with a higher RSS, indicating they are more difficult to nucleate or grow compared to View the MathML source twinning. In general a higher RSS value on the twin plane is not connected to a higher twin thickness; only in the case of View the MathML source twins the highest RSS values show clearly thicker twins. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
New York |
Editor |
|
| |
Language |
|
Wos |
000309086700004 |
Publication Date |
2012-07-10 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1044-5803; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.714 |
Times cited |
25 |
Open Access |
|
| |
Notes |
Iap |
Approved |
Most recent IF: 2.714; 2012 IF: 1.880 |
| |
Call Number |
UA @ lucian @ c:irua:101225 |
Serial |
3768 |
| Permanent link to this record |
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Author |
Phung, Q.M.; Vancoillie, S.; Delabie, A.; Pourtois, G.; Pierloot, K. |
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Title |
Ruthenocene and cyclopentadienyl pyrrolyl ruthenium as precursors for ruthenium atomic layer deposition : a comparative study of dissociation enthalpies |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Theoretical chemistry accounts : theory, computation, and modeling |
Abbreviated Journal |
Theor Chem Acc |
| |
Volume |
131 |
Issue |
7 |
Pages |
1238 |
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
RuCp2 (ruthenocene) and RuCpPy (cyclopentadienyl pyrrolyl ruthenium) complexes are used in ruthenium (Ru) atomic layer deposition (ALD) but exhibit a markedly different reactivity with respect to the substrate and co-reactant. In search of an explanation, we report here the results of a comparative study of the heterolytic and homolytic dissociation enthalpy of these two ruthenium complexes, making use of either density functional theory (DFT) or multiconfigurational perturbation theory (CASPT2). While both methods predict distinctly different absolute dissociation enthalpies, they agree on the relative values between both molecules. A reduced heterolytic dissociation enthalpy is obtained for RuCpPy compared to RuCp2, although the difference obtained from CASPT2 (19.9 kcal/mol) is slightly larger than the one obtained with any of the DFT functionals (around 17 kcal/mol). Both methods also agree on the more pronounced stability of the Cp- ligand in RuCpPy than in RuCp2 (by around 9 kcal/mol with DFT and by 6 kcal/mol with CASPT2). |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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Language |
|
Wos |
000307274300003 |
Publication Date |
2012-07-07 |
| |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1432-881X;1432-2234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.89 |
Times cited |
5 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 1.89; 2012 IF: 2.233 |
| |
Call Number |
UA @ lucian @ c:irua:101139 |
Serial |
2935 |
| Permanent link to this record |
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| |
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Author |
Grzelczak, M.; Sánchez-Iglesias, A.; Heidari Mezerji, H.; Bals, S.; Pérez-Juste, J.; Liz-Marzán, L.M. |
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Title |
Steric hindrance induces crosslike self-assembly of gold nanodumbbells |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
| |
Volume |
12 |
Issue |
8 |
Pages |
4380-4384 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
In the formation of colloidal molecules, directional interactions are crucial for controlling the spatial distribution of the building blocks. Anisotropic nanoparticles facilitate directional clustering via steric constraints imposed by each specific shape, thereby restricting assembly along certain directions. We show in this Letter that the combination of patchiness (attraction) and shape (steric hindrance) allows assembling gold nanodumbbell building blocks into crosslike dimers with well-controlled interparticle distance and relative orientation. Steric hindrance between interacting dumbbell-like particles opens up a new synthetic approach toward low-symmetry plasmonic clusters, which may significantly contribute to understand complex plasmonic phenomena. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Washington |
Editor |
|
| |
Language |
|
Wos |
000307211000081 |
Publication Date |
2012-07-05 |
| |
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 |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
12.712 |
Times cited |
85 |
Open Access |
|
| |
Notes |
Nanodirect 213948-2; 262348 Esmi |
Approved |
Most recent IF: 12.712; 2012 IF: 13.025 |
| |
Call Number |
UA @ lucian @ c:irua:101900 |
Serial |
3161 |
| Permanent link to this record |
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Author |
Gengler, R.Y.N.; Toma, L.M.; Pardo, E.; Lloret, F.; Ke, X.; Van Tendeloo, G.; Gournis, D.; Rudolf, P. |
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Title |
Prussian blue analogues of reduced dimensionality |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Small |
Abbreviated Journal |
Small |
| |
Volume |
8 |
Issue |
16 |
Pages |
2532-2540 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Mixed-valence polycyanides (Prussian Blue analogues) possess a rich palette of properties spanning from room-temperature ferromagnetism to zero thermal expansion, which can be tuned by chemical modifications or the application of external stimuli (temperature, pressure, light irradiation). While molecule-based materials can combine physical and chemical properties associated with molecular-scale building blocks, their successful integration into real devices depends primarily on higher-order properties such as crystal size, shape, morphology, and organization. Herein a study of a new reduced-dimensionality system based on Prussian Blue analogues (PBAs) is presented. The system is built up by means of a modified Langmuir-Blodgett technique, where the PBA is synthesized from precursors in a self-limited reaction on a clay mineral surface. The focus of this work is understanding the magnetic properties of the PBAs in different periodic, low-dimensional arrangements, and the influence of the “on surface” synthesis on the final properties and dimensionality of the system. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Weinheim |
Editor |
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| |
Language |
|
Wos |
000307390300012 |
Publication Date |
2012-07-03 |
| |
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 |
1613-6810; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
8.643 |
Times cited |
17 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 8.643; 2012 IF: 7.823 |
| |
Call Number |
UA @ lucian @ c:irua:101104 |
Serial |
2736 |
| Permanent link to this record |
| |
|
| |
|
Author |
Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Herber, R.H.; Nowik, I.; Hodges, J.P.; Dachraoui, W.; Hadermann, J.; Greenblatt, M.; |
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Title |
High magnetic ordering temperature in the perovskites Sr4-xLaxFe3ReO12 (x=0.0, 1.0, 2.0) |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| |
Volume |
194 |
Issue |
|
Pages |
48-58 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
A series of perovskites Sr4−xLaxFe3ReO12 (x=0.0, 1.0, 2.0) has been prepared by wet chemistry methods. The structure analyses by powder X-ray and neutron diffraction and electron microscopy show that these compounds adopt simple perovskite structures without cation ordering over the B sites: tetragonal (I4/mcm) for x=0.0 and 1.0 and orthorhombic (Pbmn) for x=2.0. The oxidation states of the cations in the compound with x=0.0 appear to be Fe3+/4+ and Re7+ and decrease for both with La substitution as evidenced by X-ray absorption spectroscopy. All the compounds are antiferromagnetically ordered above room temperature, as demonstrated by Mössbauer spectroscopy and the magnetic structures, which were determined by powder neutron diffraction. The substitution of Sr by La strongly affects the magnetic properties with an increase of TN up to ∼750 K. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
London |
Editor |
|
| |
Language |
|
Wos |
000308896400009 |
Publication Date |
2012-07-02 |
| |
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 |
9 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.299; 2012 IF: 2.040 |
| |
Call Number |
UA @ lucian @ c:irua:101220 |
Serial |
1435 |
| Permanent link to this record |
| |
|
| |
|
Author |
Van Dael, M.; Van Passel, S.; Pelkmans, L.; Guisson, R.; Swinnen, G.; Schreurs, E. |
| |
Title |
Determining potential locations for biomass valorization using a macro screening approach |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Biomass & Bioenergy |
Abbreviated Journal |
Biomass Bioenerg |
| |
Volume |
45 |
Issue |
|
Pages |
175-186 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
| |
Abstract |
European policy states that by 2020 at least 20% of final energy consumption should come from renewable energy sources. Biomass as a renewable energy source cannot be disregarded in order to attain this target. In this study a macro screening approach is developed to determine potential locations for biomass valorization in a specified region. The approach consists of five steps: (1) criteria determination, (2) data gathering, (3) weight assignment, (4) final score, (5) spatial representation. The resulting outcome provides a first well balanced scan of the possibilities for energy production using regional biomass. This way policy makers and investors can be supported and motivated to study the possibilities of building energy production plants at specific locations in more detail, which can be described as a 'micro-screening'. In our case study the approach is applied to determine the potentially interesting locations to establish a biomass project. The region has been limited to the forty-four communities in the province of Limburg (Belgium). The macro screening approach has shown to be very effective since the amount of interesting locations has been reduced drastically. (c) 2012 Elsevier Ltd. All rights reserved. |
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Address |
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| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000308384500019 |
Publication Date |
2012-06-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0961-9534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.219 |
Times cited |
23 |
Open Access |
|
| |
Notes |
; The authors gratefully acknowledge the financial support from INTERREG and the province of Limburg. Special thanks to our colleague Thomas Voets for his effort in making the GIS maps. Moreover, the authors would like to thank the two anonymous reviewers for their valuable comments. ; |
Approved |
Most recent IF: 3.219; 2012 IF: 2.975 |
| |
Call Number |
UA @ admin @ c:irua:127554 |
Serial |
6178 |
| Permanent link to this record |
| |
|
| |
|
Author |
Berdiyorov, G.R.; Milošević, M.V.; Peeters, F.M. |
| |
Title |
Spatially dependent sensitivity of superconducting meanders as single-photon detectors |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| |
Volume |
100 |
Issue |
26 |
Pages |
262603 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The photo-response of a thin current-carrying superconducting stripe with a 90 degrees turn is studied within the time-dependent Ginzburg-Landau theory. We show that the photon acting near the inner corner (where the current density is maximal due to the current crowding [J. R. Clem and K. K. Berggren, Phys. Rev. B 84, 174510 (2011)]) triggers the nucleation of superconducting vortices at currents much smaller than the expected critical one, but does not bring the system to a higher resistive state and thus remains undetected. The transition to the resistive state occurs only when the photon hits the stripe away from the corner due to there uniform current distribution across the sample, and dissipation is due to the nucleation of a kinematic vortex-antivortex pair near the photon incidence. We propose strategies to account for this problem in the measurements. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4731627] |
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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 |
|
Wos |
000305831500057 |
Publication Date |
2012-06-28 |
| |
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 |
27 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI). G. R. B. acknowledges individual support from FWO-VI. ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
| |
Call Number |
UA @ lucian @ c:irua:100336 |
Serial |
3066 |
| Permanent link to this record |
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|
| |
|
Author |
Zhao, H.J.; Misko, V.R.; Peeters, F.M. |
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Title |
Analysis of pattern formation in systems with competing range interactions |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
| |
Volume |
14 |
Issue |
|
Pages |
063032 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We analyzed pattern formation and identified various morphologies in a system of particles interacting through a non-monotonic potential with a competing range interaction characterized by a repulsive core (r < r(c)) and an attractive tail (r > r(c)), using molecular-dynamics simulations. Depending on parameters, the interaction potential models the inter-particle interaction in various physical systems ranging from atoms, molecules and colloids to vortices in low kappa type-II superconductors and in recently discovered 'type-1.5' superconductors. We constructed a 'morphology diagram' in the plane 'critical radius r(c)-density n' and proposed a new approach to characterizing the different types of patterns. Namely, we elaborated a set of quantitative criteria in order to identify the different pattern types, using the radial distribution function (RDF), the local density function and the occupation factor. |
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Address |
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Corporate Author |
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Thesis |
|
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Publisher |
|
Place of Publication |
Bristol |
Editor |
|
| |
Language |
|
Wos |
000306946600003 |
Publication Date |
2012-06-25 |
| |
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 |
45 |
Open Access |
|
| |
Notes |
; We acknowledge useful discussions with Ernst Helmut Brandt, Charles Reichhardt and Cynthia Olson Reichhardt. This work was supported by the 'Odysseus' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.786; 2012 IF: 4.063 |
| |
Call Number |
UA @ lucian @ c:irua:101140 |
Serial |
102 |
| Permanent link to this record |
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Author |
Aghaei, M.; Lindner, H.; Bogaerts, A. |
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Title |
Optimization of operating parameters for inductively coupled plasma mass spectrometry : a computational study |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
Abbreviated Journal |
Spectrochim Acta B |
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Volume |
76 |
Issue |
|
Pages |
56-64 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
An inductively coupled plasma, connected to a mass spectrometer interface, is computationally investigated. The effect of pressure behind the sampler, injector gas flow rate, auxiliary gas flow rate, and applied power is studied. There seems to be an optimum range of injector gas flow rate for each setup which guaranties the presence and also a proper length of the central channel in the torch. Moreover, our modeling results show that for any specific purpose, it is possible to control that either only the central gas flow passes through the sampler orifice or that it is accompanied by the auxiliary gas flow. It was also found that depending on geometry, the variation of outgoing gas flow rate is much less than the variation of the injector gas flow rate and this causes a slightly higher pressure inside the torch. The general effect of increasing the applied power is a rise in the plasma temperature, which results in a higher ionization in the coil region. However, the negative effect is reducing the length of the cool central channel which is important to transfer the sample substances to the sampler. Using a proper applied power can enhance the efficiency of the system. Indeed, by changing the gas path lines, the power can control which flow (i.e., only from injector gas or also from the auxiliary gas) goes to the sampler orifice. Finally, as also reported from experiments in literature, the pressure behind the sampler has no dramatic effect on the plasma characteristics. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
|
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Language |
|
Wos |
000311008600008 |
Publication Date |
2012-06-23 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
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Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0584-8547; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.241 |
Times cited |
18 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.241; 2012 IF: 3.141 |
| |
Call Number |
UA @ lucian @ c:irua:101356 |
Serial |
2488 |
| Permanent link to this record |
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Author |
Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Henry, P.F.; Janson, O.; Rosner, H. |
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Title |
Short-range order of Br and three-dimensional magnetism in (CuBr)LaNb2O7 |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
21 |
Pages |
214427 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
We present a comprehensive study of the crystal structure, magnetic structure, and microscopic magnetic model of (CuBr)LaNb2O7, the Br analog of the spin-gap quantum magnet (CuCl) LaNb2O7. Despite similar crystal structures and spin lattices, the magnetic behavior and even peculiarities of the atomic arrangement in the Cl and Br compounds are very different. The high- resolution x-ray and neutron data reveal a split position of Br atoms in (CuBr) LaNb2O7. This splitting originates from two possible configurations developed by [CuBr] zigzag ribbons. While the Br atoms are locally ordered in the ab plane, their arrangement along the c direction remains partially disordered. The predominant and energetically more favorable configuration features an additional doubling of the c lattice parameter that was not observed in (CuCl) LaNb2O7. (CuBr) LaNb2O7 undergoes long-range antiferromagnetic ordering at T-N = 32 K, which is nearly 70% of the leading exchange coupling J4 similar or equal to 48 K. The Br compound does not show any experimental signatures of low-dimensional magnetism because the underlying spin lattice is three-dimensional. The coupling along the c direction is comparable to the couplings in the ab plane, even though the shortest Cu-Cu distance along c (11.69 angstrom) is three times larger than nearest-neighbor distances in the ab plane (3.55 angstrom). The stripe antiferromagnetic long-range order featuring columns of parallel spins in the ab plane and antiparallel spins along c is verified experimentally and confirmed by the microscopic analysis. |
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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 |
000305557600002 |
Publication Date |
2012-06-22 |
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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 |
5 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:100289 |
Serial |
2998 |
| Permanent link to this record |
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Author |
Komulainen, S.; Verlackt, C.; Pursiainen, J.; Lajunen, M. |
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Title |
Oxidation and degradation of native wheat starch by acidic bromate in water at room temperature |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Carbohydrate Polymers |
Abbreviated Journal |
Carbohyd Polym |
| |
Volume |
93 |
Issue |
1 |
Pages |
73-80 |
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Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
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Abstract |
Native wheat starch was oxidized by benign acidic bromate in water at room temperature. HPLC-ELSD study indicated that starch degraded in the course of oxidation but it still had a polymeric structure characterized by H-1, C-13, HSQC and HMBC NMR measurements. Products were generally water-soluble fragments but the use of a short reaction time and dilute reaction mixture yielded water-insoluble products. Titration of the products showed, that the increase of the starch content and reaction time increased the content of carbonyl and carboxyl groups in the range of 0.5-2.5% and 1.7-17.2%, respectively, in the product fragments. A mechanism for the oxidation reaction was proposed. (C) 2012 Elsevier Ltd. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
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Language |
|
Wos |
000316512900011 |
Publication Date |
2012-06-21 |
| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0144-8617; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.811 |
Times cited |
32 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.811; 2013 IF: 3.916 |
| |
Call Number |
UA @ lucian @ c:irua:108288 |
Serial |
2537 |
| Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
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Title |
Ultra-small metallic grains : effect of statistical fluctuations of the chemical potential on superconducting correlations and vice versa |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| |
Volume |
24 |
Issue |
27 |
Pages |
275701 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Superconducting correlations in an isolated metallic grain are governed by the interplay between two energy scales: the mean level spacing delta and the bulk pairing gap Delta(0), which are strongly influenced by the position of the chemical potential with respect to the closest single-electron level. In turn superconducting correlations affect the position of the chemical potential. Within the parity projected BCS model we investigate the probability distribution of the chemical potential in a superconducting grain with randomly distributed single-electron levels. Taking into account statistical fluctuations of the chemical potential due to the pairing interaction, we find that such fluctuations have a significant impact on the critical level spacing delta(c) at which the superconducting correlations cease: the critical ratio delta(c)/Delta(0) at which superconductivity disappears is found to be increased. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
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Language |
|
Wos |
000305653100012 |
Publication Date |
2012-06-21 |
| |
Series Editor |
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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 |
9 |
Open Access |
|
| |
Notes |
; This work was supported by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF network INSTANS. MDC and AAS are grateful to A Vagov for stimulating discussions. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:100280 |
Serial |
3793 |
| Permanent link to this record |
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Author |
Akbulut, S.; Van Grieken, R.; Kilic, M.A.; Čevik, U.; Rotondo, G.G. |
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Title |
Identification of heavy metal origins related to chemical and morphological soil properties using several non-destructive X-ray analytical methods |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Environmental monitoring and assessment |
Abbreviated Journal |
|
| |
Volume |
185 |
Issue |
3 |
Pages |
2377-2394 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Soils are complex mixtures of organic, inorganic materials, and metal compounds from anthropogenic sources. In order to identify the pollution sources, their magnitude and development, several X-ray analytical methods were applied in this study. The concentrations of 16 elements were determined in all the soil samples using energy dispersive X-ray fluorescence spectrometry. Soils of unknown origin were observed by scanning electron microscopy equipped with a Si(Li) X-ray detector using Monte Carlo simulation approach. The mineralogical analyses were carried out using X-ray diffraction spectrometry. Due to the correlations between heavy metals and oxide compounds, the samples were analyzed also by electron probe microanalyzer (EPMA) in order to have information about their oxide contents. On the other hand, soil pH and salinity levels were identified owing to their influence between heavy metal and soil-surface chemistry. Moreover, the geoaccumulation index (I geo) enables the assessment of contamination by comparing current and pre-industrial concentrations. |
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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 |
000314033300029 |
Publication Date |
2012-06-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
| |
ISSN |
1420-2026; 1573-2967 |
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:106755 |
Serial |
8052 |
| Permanent link to this record |
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Author |
Marikutsa, A.; Krivetskiy, V.; Yashina, L.; Rumyantseva, M.; Konstantinova, E.; Ponzoni, A.; Comini, E.; Abakumov, A.; Gaskov, A. |
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Title |
Catalytic impact of RuOx clusters to high ammonia sensitivity of tin dioxide |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Sensors and actuators : B : chemical
T2 – 25th Eurosensors Conference, SEP 04-07, 2011, Athens, GREECE |
Abbreviated Journal |
Sensor Actuat B-Chem |
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Volume |
175 |
Issue |
|
Pages |
186-193 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
A comparative study of NH3-sensing performance of blank and modified nanocrystal line SnO2 was performed. Tin dioxide modified by ruthenium displayed the highest ammonia sensitivity with a maximum signal at 200 degrees C. The modifier was shown by XPS and EPR to occur in a mixed valence state of oxidized ruthenium distributed between the surface and bulk of tin dioxide nanocrystals. RuOx clustering on SnO2 surface was detected by means of electron microscopy assisted EDX-mapping. The effect of RuOx on tin dioxide interaction with ammonia was studied by temperature-programmed NH3 desorption, simultaneous Kelvin probe and DC-resistance measurements, EPR spectroscopy and analyses of the gas-solid interaction products. The modifier was shown to promote the materials reactivity to NH3 due to the catalytic activity of RuOx. The interaction with ammonia resulted in dipoles formation on the oxide surface along with reducing the grains net surface charge, established from the electron affinity increase and resistance decrease during NH3 exposure. The RuOx-catalyzed gas-solid interaction was deduced to proceed deeper than in the case of non-modified SnO2 and to yield nitrogen oxides (e.g. NO2), as was suggested by the oxidative character of gaseous products of NH3 interaction with RuOx-modified tin dioxide at 200 degrees C. (C) 2012 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
|
Wos |
000312358700033 |
Publication Date |
2012-06-19 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
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Edition |
|
| |
ISSN |
0925-4005; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.401 |
Times cited |
20 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 5.401; 2012 IF: 3.535 |
| |
Call Number |
UA @ lucian @ c:irua:105985 |
Serial |
293 |
| Permanent link to this record |
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Author |
Čukarić, N.; Arsoski, V.; Tadić, M.; Peeters, F.M. |
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Title |
Hole states in nanocups in a magnetic field |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
23 |
Pages |
235425-235425,11 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The magnetic-field dependence of the hole states in a nanocup, which is composed of a ring (the nanocup rim) that surrounds a disk (the nanocup bottom), is obtained within the Luttinger-Kohn model for the unstrained GaAs/(Al,Ga) As and the strained (In,Ga) As/GaAs systems. Aharonov-Bohm oscillations due to angular momentum transitions of the hole ground state appear with periods that vary with the thickness of the disk. The strain in the (In, Ga) As/GaAs nanocup is sensitive to the disk thickness and favors the spatial localization of the heavy holes inside the disk. Therefore, the angular momentum transitions between the valence-band states disappear for much thinner disks than in the case of the unstrained GaAs/(Al, Ga) As nanocups. In both systems, the oscillations in the energy of the hole ground state are found to disappear for thinner inner layer than in the electron ground-state energy. This is due to the different confining potentials and the mixing between the heavy- and light-hole states. As a consequence, magnetization of the single hole is found to strongly depend on the bottom thickness of the strained (In, Ga) As/GaAs nanocup. Furthermore, we found that the strain can lead to a spatial separation of the electron and the hole, as in type-II band alignment, which is advantageous for the appearance of the excitonic Aharonov-Bohm effect. |
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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 |
000305116700005 |
Publication Date |
2012-06-14 |
| |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
4 |
Open Access |
|
| |
Notes |
; The authors thank B. Partoens for useful discussions. This work was supported by the EU NoE: SANDiE, the Ministry of Education and Science of Serbia, and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:98906 |
Serial |
1477 |
| Permanent link to this record |
| |
|
| |
|
Author |
Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. |
| |
Title |
Magnetotransport in periodically modulated bilayer graphene |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
24 |
Pages |
245426-245426,10 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Magnetotransport in bilayer graphene in the presence of a weak and periodic potential is investigated in the presence of a perpendicular magnetic field B. The modulation broadens the Landau levels into bands and for weak magnetic fields leads to the well-known Weiss oscillations in their bandwidth and their transport coefficients at very low B and to the Shubnikov-de Haas oscillations at larger B. The amplitude of the Weiss oscillations is severely reduced if the periodic potentials applied to the two layers oscillate out of phase. We also contrast some results with those corresponding to single-layer graphene. Relative to them the flat-band condition and the oscillation amplitude differ substantially, due to the interlayer coupling, and agree only when this coupling is extremely weak. We further show that the Hall conductivity exhibits the well-known steps at half-integer and integer multiples of 4e(2)/h in single-layer and bilayer graphene, respectively, even for very weak magnetic fields. The results are pertinent to weak and periodic corrugations when the potential modulation dominates the strain-induced magnetic modulation. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000305253600012 |
Publication Date |
2012-06-14 |
| |
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 |
21 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CON-GRAN), and the Canadian NSERC Grant No. OGP0121756. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:99077 |
Serial |
1934 |
| Permanent link to this record |
| |
|
| |
|
Author |
Chen, Y.; Shanenko, A.A.; Peeters, F.M. |
| |
Title |
Superconducting transition temperature of Pb nanofilms : impact of thickness-dependent oscillations of the phonon-mediated electron-electron coupling |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
22 |
Pages |
224517-224517,6 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
To date, several experimental groups reported measurements of the thickness dependence of T-c of atomically uniform single-crystalline Pb nanofilms. The reported amplitude of the T-c oscillations varies significantly from one experiment to another. Here we propose that the reason for this unresolved issue is an interplay of the quantum-size variations in the single-electron density of states with thickness-dependent oscillations in the phonon-mediated electron-electron coupling. Such oscillations in the coupling depend on the substrate material, the quality of the interface, the protection cover, and other details of the fabrication process, changing from one experiment to another. This explains why the available data do not exhibit one-voice consistency about the amplitude of the T-c oscillations. Our analyses are based on a numerical solution of the Bogoliubov-de Gennes equations for a superconducting slab. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000305251300006 |
Publication Date |
2012-06-14 |
| |
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 |
24 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:99076 |
Serial |
3368 |
| Permanent link to this record |
| |
|
| |
|
Author |
Mishra, V.K.; Kumar, P.; Van Poppel, M.; Bleux, N.; Frijns, E.; Reggente, M.; Berghmans, P.; Int Panis, L.; Samson, R. |
| |
Title |
Wintertime spatio-temporal variation of ultrafine particles in a Belgian city |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
The science of the total environment |
Abbreviated Journal |
|
| |
Volume |
431 |
Issue |
|
Pages |
307-313 |
| |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
| |
Abstract |
Simultaneous measurements of ultrafine particles (UFPs) were carried out at four sampling locations situated within a 1 km(2) grid area in a Belgian city, Borgerhout (Antwerp). All sampling sites had different orientation and height of buildings and dissimilar levels of anthropogenic activities (mainly traffic volume). The aims were to investigate: (i) the spatio-temporal variation of UFP within the area, (ii) the effect of wind direction with respect to the volume of traffic on UFP levels, and (iii) the spatial representativeness of the official monitoring station situated in the study area. All sampling sites followed similar diurnal patterns of UFP variation, but effects of local traffic emissions were evident. Wind direction also had a profound influence on UFP concentrations at certain sites. The results indicated a clear influence of local weather conditions and the more dominant effect of traffic volumes. Our analysis indicated that the regional air quality monitoring station represented the other sampling sites in the study area reasonably well; temporal patterns were found to be comparable though the absolute average concentrations showed differences of up to 35%. (C) 2012 Elsevier B.V. All rights reserved. |
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Address |
|
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000306887900037 |
Publication Date |
2012-06-14 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0048-9697; 1879-1026 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
| |
Notes |
|
Approved |
no |
| |
Call Number |
UA @ admin @ c:irua:101123 |
Serial |
8759 |
| Permanent link to this record |
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|
| |
|
Author |
Bals, S.; Van Aert, S.; Romero, C.P.; Lauwaet, K.; Van Bael, M.J.; Schoeters, B.; Partoens, B.; Yuecelen, E.; Lievens, P.; Van Tendeloo, G. |
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Title |
Atomic scale dynamics of ultrasmall germanium clusters |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
| |
Volume |
3 |
Issue |
897 |
Pages |
897 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| |
Abstract |
Starting from the gas phase, small clusters can be produced and deposited with huge flexibility with regard to composition, materials choice and cluster size. Despite many advances in experimental characterization, a detailed morphology of such clusters is still lacking. Here we present an atomic scale observation as well as the dynamical behaviour of ultrasmall germanium clusters. Using quantitative scanning transmission electron microscopy in combination with ab initio calculations, we are able to characterize the transition between different equilibrium geometries of a germanium cluster consisting of less than 25 atoms. Seven-membered rings, trigonal prisms and some smaller subunits are identified as possible building blocks that stabilize the structure. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000306099900024 |
Publication Date |
2012-06-12 |
| |
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 |
90 |
Open Access |
|
| |
Notes |
Fwo; Iap; Iwt |
Approved |
Most recent IF: 12.124; 2012 IF: 10.015 |
| |
Call Number |
UA @ lucian @ c:irua:100340 |
Serial |
183 |
| Permanent link to this record |
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| |
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Author |
Chen, Y.; Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
| |
Title |
Quantum cascades in nano-engineered superconductors : geometrical, thermal and paramagnetic effects |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| |
Volume |
24 |
Issue |
26 |
Pages |
265702 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The effect of a parallel magnetic field on the orbital motion of electrons in high-quality superconducting nanowires resulting in a superconductor-to-normal transition which occurs through a cascade of jumps in the order parameter as a function of the magnetic field. Such cascades originate from the transverse size quantization that splits the conduction band into a series of subbands. Here, based on a numerical solution of the Bogoliubov-de Gennes equations for a hollow nanocylinder, we investigate how the quantum-size cascades depend on the confining geometry, i.e., by changing the cylinder radius R and its thickness d we cover the range from the nanowire-like to the nanofilm-like regime. The cascades are shown to become much less pronounced when increasing R/d, i.e., when the nanofilm-like regime is approached. When the temperature is non-zero they are thermally smoothed. This includes the spin-magnetic-field interaction which reduces the critical (depairing) parallel magnetic field H-c,H-parallel to but does not have any qualitative effect on the quantum cascades. From our calculations it is seen that the paramagnetic limiting field H-par significantly exceeds H-c,H-parallel to even in extremely narrow nanocylinders, i.e., when R, d are down to a few nanometers, and H-c,H-parallel to is only about 10% larger when switching-off the spin-magnetic-field interaction in this case. Both characteristic fields, H-c,H-parallel to and H-par, exhibit pronounced quantum-size oscillations. We demonstrate that the quantum cascades and the quantum-size oscillations survive in the presence of surface roughness. |
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Address |
|
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Corporate Author |
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Thesis |
|
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Publisher |
|
Place of Publication |
London |
Editor |
|
| |
Language |
|
Wos |
000305640800014 |
Publication Date |
2012-06-07 |
| |
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 |
6 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the ESF-AQDJJ network. MDC acknowledges the support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
| |
Call Number |
UA @ lucian @ c:irua:100281 |
Serial |
2773 |
| Permanent link to this record |
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| |
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Author |
Klingstedt, M.; Sundberg, M.; Eriksson, L.; Haigh, S.; Kirkland, A.; Grüner, D.; de Backer, A.; Van Aert, S.; Tarasaki, O. |
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Title |
Exit wave reconstruction from focal series of HRTEM images, single crystal XRD and total energy studies on SbxWO3+y (x\sim0.11) |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Zeitschrift für Kristallographie |
Abbreviated Journal |
Z Krist-Cryst Mater |
| |
Volume |
227 |
Issue |
6 |
Pages |
341-349 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
A new tungsten bronze in the SbWO system has been prepared in a solid state reaction from Sb2O3, WO3 and W metal powder. The average structure was determined by single crystal X-ray diffraction. SbxWO3+y (x ∼ 0.11) crystallizes in the orthorhombic space group Pm21n (no. 31), a = 27.8135(9) Å, b = 7.3659(2) Å and c = 3.8672(1) Å. The structure belongs to the (n)-ITB class of intergrowth tungsten bronzes. It contains slabs of hexagonal channels formed by six WO6 octahedra. These slabs are separated by three layers of WO6 octahedra that are arranged in a WO3-type fashion. The WO6 octahedra share all vertices to build up a three-dimensional framework. The hexagonal channels are filled with Sb atoms to ∼80% and additional O atoms. The atoms are shifted out of the center of the channels. Exit-wave reconstruction of focal series of high resolution-transmission-electron-microscope (HRTEM) images combined with statistical paramäeter estimation techniques allowed to study local ordering in the channels. Sb atoms in neighbouring channels tend to be displaced in the same direction, which is in agreement with total energy calculations on ordered structure models, but the ratio of the occupation of the two possible Sb sites varies from channel to channel. The structure of SbxWO3+y exhibits pronounced local modulations. |
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Address |
|
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
München |
Editor |
|
| |
Language |
|
Wos |
000307314200003 |
Publication Date |
2012-06-06 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2194-4946; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.179 |
Times cited |
4 |
Open Access |
|
| |
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 3.179; 2012 IF: NA |
| |
Call Number |
UA @ lucian @ c:irua:101218 |
Serial |
1131 |
| Permanent link to this record |
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| |
|
Author |
Krstajić, P.M.; Peeters, F.M. |
| |
Title |
Energy-momentum dispersion relation of plasmarons in graphene |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
20 |
Pages |
205454-205454,4 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The many-body correction to the band structure of a quasi-free-standing graphene layer is obtained within the Overhauser approach, where the electron-plasmon interaction is described as a field theoretical problem. We find that the Dirac-like spectrum is shifted by Delta E(k = 0), which is on the order of 50-150 meV, depending on the electron concentration n(e), and is in semiquantitative agreement with experimental data. The value of the Fermi velocity is renormalized by several percents and decreases with increasing electron concentration as found experimentally. |
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Address |
|
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000304649900004 |
Publication Date |
2012-06-05 |
| |
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 |
11 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE project CON-GRAN, and the Serbian Ministry of Education and Science (project No. TR 32008). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:98937 |
Serial |
1043 |
| Permanent link to this record |
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|
| |
|
Author |
Ramos, I.R.O.; Ferreira, W.P.; Munarin, F.F.; Farias, G.A.; Peeters, F.M. |
| |
Title |
Bilayer crystals of charged magnetic dipoles : structure and phonon spectrum |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
| |
Volume |
85 |
Issue |
5:1 |
Pages |
051404-051404,12 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We study the structure and phonon spectrum of a two-dimensional bilayer system of classical charged dipoles oriented perpendicular to the plane of the layers for equal density in each layer. This system can be tuned through six different crystalline phases by changing the interlayer separation or the charge and/or dipole moment of the particle. The presence of the charge on the dipole particles is responsible for the nucleation of five staggered phases and a disordered phase which are not found in the magnetic dipole bilayer system. These extra phases are a consequence of the competition between the repulsive Coulomb and the attractive dipole interlayer interaction. We present the phase diagram and determine the order of the phase transitions. The phonon spectrum of the system was calculated within the harmonic approximation, and a nonmonotonic behavior of the phonon spectrum is found as a function of the effective strength of the interparticle interaction. The stability of the different phases is determined. |
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Address |
|
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Corporate Author |
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Thesis |
|
| |
Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
|
| |
Language |
|
Wos |
000304403400002 |
Publication Date |
2012-05-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
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 |
8 |
Open Access |
|
| |
Notes |
; This work was supported by the Brazilian agencies CNPq, CAPES, and FUNCAP (PRONEX grant), the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, and the CNPq-FWO collaborating project. The authors are grateful to Prof. G. Goldoni for some technical clarifications concerning Ref. [18]. ; |
Approved |
Most recent IF: 2.366; 2012 IF: 2.313 |
| |
Call Number |
UA @ lucian @ c:irua:98940 |
Serial |
233 |
| Permanent link to this record |
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|
| |
|
Author |
Badalyan, S.M.; Peeters, F.M. |
| |
Title |
Electron-phonon bound state in graphene |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
20 |
Pages |
205453-205453,5 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The fine structure of the Dirac energy spectrum in graphene induced by electron-optical phonon coupling is investigated in the portion of the spectrum near the phonon emission threshold. The derived new dispersion equation in the immediate neighborhood below the threshold corresponds to an electron-phonon bound state. We find that the singular vertex corrections beyond perturbation theory strongly increase the electron-phonon binding energy scale. The predicted enhancement of the effective electron-phonon coupling can be measured using angle-resolved spectroscopy. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000304649400002 |
Publication Date |
2012-05-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
|
| |
Notes |
; We thank E. Rashba for the useful discussion and acknowledge support from the Belgian Science Policy (IAP) and BELSPO. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:98939 |
Serial |
982 |
| Permanent link to this record |
