| Records |
| Author |
Esken, D.; Noei, H.; Wang, Y.; Wiktor, C.; Turner, S.; Van Tendeloo, G.; Fischer, R.A. |
| Title |
ZnO@ZIF-8 : stabilization of quantum confined ZnO nanoparticles by a zinc methylimidazolate framework and their surface structural characterization probed by CO2 adsorption |
Type |
A1 Journal article |
Year  |
2011 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
| Volume |
21 |
Issue |
16 |
Pages |
5907-5915 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The microporous and activated zeolitic imidazolate framework (Zn(MeIM)2; MeIM = imidazolate-2-methyl; ZIF-8) was loaded with the MOCVD precursor diethyl zinc [Zn(C2H5)2]. Exposure of ZIF-8 to the vapour of the volatile organometallic molecule resulted in the formation of the inclusion compound [Zn(C2H5)2]0.38@ZIF-8 revealing two precursor molecules per cavity. In a second step the obtained material was treated with oxygen (5 vol% in argon) at various temperatures (oxidative annealing) to achieve the composite material ZnO0.35@ZIF-8. The new material was characterized with powder XRD, FT-IR, UV-vis, solid state NMR, elemental analysis, N2 sorption measurements, and transmission electron microscopy. The data give evidence for the presence of nano-sized ZnO particles stabilized by ZIF-8 showing a blue-shift of the UV-vis absorption caused by quantum size effect (QSE). The surface structure and reactivity of embedded ZnO nanoparticles were characterized via carbon dioxide adsorption at different temperatures monitored by ultra-high vacuum FTIR techniques. It was found that the surface of ZnO nanoparticles is dominated by polar OZnO and ZnZnO facets as well as by defect sites, which all exhibit high reactivity towards CO2 activation forming various adsorbed carbonate and chemisorbed CO2δ− species. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000289260000012 |
Publication Date |
2011-03-19 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
76 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:88641 |
Serial |
3936 |
| Permanent link to this record |
| |
|
| |
| Author |
Pei, Z.-G.; Shan, X.-Q.; Zhang, S.-Z.; Kong, J.-J.; Wen, B.; Zhang, J.; Zheng, L.-R.; Xie, Y.-N.; Janssens, K. |
| Title |
Insight to ternary complexes of co-adsorption of norfloxacin and Cu(II) onto montmorillonite at different pH using EXAFS |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
| Volume |
186 |
Issue |
1 |
Pages |
842-848 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Co-adsorption of norfloxacin (Nor) and Cu(II) on montmorillonite at pH 4.5, 7.0 and 9.0 was studied by integrated batch adsorption experiments and extended X-ray absorption fine structure (EXAFS) spectroscopy. Under such pH conditions the dominant species of Nor are cation (Nor+), zwitterion (Nor±), and anion (Nor−), respectively. Results indicated that Nor sorption decreased with an increase of solution pH. The presence of Cu(II) slightly suppressed the Nor+ sorption at pH 4.5, while increased Nor± and Nor−sorption on montmorillonite at pH 7.0 and 9.0, respectively. In contrast, Nor increased Cu(II) adsorption at pH 4.5, but had little effect on the adsorption of Cu(II) on montmorillonite at pH 7.0 and 9.0. Spectroscopic results showed that, at pH 4.5, Nor+ was sorbed on montmorillonite by the formation of outer-sphere montmorilloniteNorCu(II) ternary surface complex. At pH 7.0, montmorilloniteNorCu(II) and montmorilloniteCu(II)Nor ternary surface complexes co-exist. At pH 9.0, montmorilloniteCu(II)Nor ternary surface complex was likely formed, which was different to Cu(II)(Nor)2 precipitate of the solution. |
| 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 |
000288102400107 |
Publication Date |
2010-11-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0304-3894 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.065 |
Times cited |
25 |
Open Access |
|
| Notes |
; This work was funded by the National Natural Science Foundation of China (grant numbers: 41071308, 20707037, 20737003 and 20877087) and the Youth Fund of State Key Laboratory of Environmental Chemistry and Ecotoxicology QN2009-07. ; |
Approved |
Most recent IF: 6.065; 2011 IF: 4.173 |
| Call Number |
UA @ admin @ c:irua:88786 |
Serial |
5664 |
| Permanent link to this record |
| |
|
| |
| Author |
Čevik, U.; Damla, N.; Van Grieken, R.; Vefa Akpinar, M. |
| Title |
Chemical composition of building materials used in Turkey |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Construction and building materials |
Abbreviated Journal |
|
| Volume |
25 |
Issue |
4 |
Pages |
1546-1552 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
The main goal of this work was to determine the chemical composition of building materials used in Turkey by utilizing energy dispersive X-ray fluorescence (EDXRF) spectrometry. Gas concrete, cement, sand, bricks, roofing tiles, marble, lime and gypsum materials were selected as building materials for this research. The chemical contents and their trace concentrations of the selected samples were determined. The most abundant oxides measured were generally SiO2, Al2O3, CaO, MgO, Fe2O3, K2O and SO3 for all samples. While the main chemical component of gas concrete, cement, sand and marble samples were SiO2 and CaO, brick and roofing tile mainly consisted of SiO2 and Al2O3. CaO and SO3 were major component of lime and gypsum samples, respectively. For U and Th concentrations in the samples, activities of 226Ra and 232Th were measured by utilizing gamma spectrometry. ANOVA and Pearson correlation analyses were performed on the studied data for statistical analysis. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
|
| Language |
|
Wos |
000287379300007 |
Publication Date |
2010-09-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0950-0618 |
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:86448 |
Serial |
7653 |
| Permanent link to this record |
| |
|
| |
| Author |
Jain, R.; Rather, J.A.; Dwivedi, A. |
| Title |
Voltammetric behaviour of nitroxazepine in solubilized system and biological fluids |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
|
| Volume |
31 |
Issue |
2 |
Pages |
230-237 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
This study reports the development and validation of sensitive and selective assay method for the determination of the antidepressant drug in solubilized system and biological fluids. Solubilized system of different surfactants including cationic, anionic and non-ionic influences the electrochemical response of drug. Addition of cationic surfactant cetrimide to the solution containing drug enhances the peak current signal while anionic and non-ionic showed an opposite effect. The current signal due to reduction process was function of concentration of nitroxazepine, pH, type of surfactant and preconcentration time at the electrode surface. The reduction process is irreversible and adsorption controlled at HMDE. Various chemical and instrumental parameters affecting the monitored electroanalytical response were investigated and optimized for niroxazepine hydrochloride determination. The proposed SWCAdSV and DPCAdSV methods are linear over the concentration range 2.0 × 10-7 5.0 × 10-9 mol/L and 6.1 × 10-7 1.0 × 10-8 mol/L with detection limit of 1.62 × 10-10 mo/L and 1.4 × 10-9 mo/L respectively. The method shows good sensitivity, selectivity, accuracy and precision that makes it very suitable for determination of nitroxazepine in pharmaceutical formulation and biological fluids. |
| 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 |
|
| Language |
|
Wos |
000286707900024 |
Publication Date |
2010-09-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0928-4931 |
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:98685 |
Serial |
8743 |
| Permanent link to this record |
| |
|
| |
| Author |
Dadsetani, M.; Titantah, J.T.; Lamoen, D. |
| Title |
Ab initio calculation of the energy-loss near-edge structure of some carbon allotropes: comparison with n-diamond |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Diamond and related materials |
Abbreviated Journal |
Diam Relat Mater |
| Volume |
19 |
Issue |
1 |
Pages |
73-77 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The energy-loss near-edge structure (ELNES) spectra of several carbon allotropes (non-hydrogenated and hydrogenated face-centered cubic (FCC) carbon, rhombohedral carbon, glitter, hexagonite and lonsdaleite) are calculated within the supercell-core-excited density functional theory approach. In particular an experimental ELNES spectrum of new diamond (n-diamond) [Konyashin et al., Diamond Relat. Mater. 10, (2001) 99102] is compared with the ELNES spectra of FCC carbon, rhombohedral carbon and the so-called glitter structure. Our calculations show that the ELNES spectrum considered in that publication cannot be that of FCC carbon. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000274234500013 |
Publication Date |
2009-11-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0925-9635; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.561 |
Times cited |
11 |
Open Access |
|
| Notes |
Goa; Esteem 026019 |
Approved |
Most recent IF: 2.561; 2010 IF: 1.825 |
| Call Number |
UA @ lucian @ c:irua:79444 |
Serial |
29 |
| Permanent link to this record |
| |
|
| |
| Author |
Esken, D.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Fischer, R.A. |
| Title |
Au@ZIFs: stabilization and encapsulation of cavity-size matching gold clusters inside functionalized Zeolite Imidazolate Frameworks, ZIFs |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
22 |
Issue |
23 |
Pages |
6393-6401 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The selective formation and stabilization of very small, naked metal particles inside the cavities of metal organic frameworks (MOFs) and the simultaneous realization of an even distribution of the particles throughout the crystalline MOF host matrix over a wide range of metal loading are challenging goals. MOFs reveal high specific surface areas, tunable pore sizes, and organic linkers, which are able to interact with guests. The chemically very robust zeolite imidazolate frameworks (ZIFs) are a subclass of MOFs. We chose the microporous sodalite-like ZIF-8 (Zn(MelM)(2); IM = imidazolate) and ZIF-90 (Zn(ICA)(2); ICA = imidazolate-2-carboxyaldehyde) as host matrices to influence the dispersion of imbedded gold nanoparticles (Au NPs). The metal loading was achieved via gas phase infiltration of [Au(CO)Cl] followed by a thermal hydrogenation step to form the Au NPs. Low-dose high-resolution transmission electron microscopy ((HR)TEM) and electron tomography reveal a homogeneous distribution of Au NPs throughout the ZIF matrix. The functional groups of ZIF-90 direct the anchoring of intermediate Au species and stabilize drastically smaller and quite monodisperse Au NPs in contrast to the parent not functionalized ZIF-8. The particles can be very small, match the cavity size and approach defined molecular clusters of magic numbers, i.e., Au(55), independently from the level of loading. Post-synthetic oxidation of the aldehyde groups to yield alkyl esters by the adjacent, catalytically active metal NPs is presented as a new concept of encapsulating nanoparticles inside MOFs and allows multiple steps of metal loadings without decomposition of the MOF. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000284975100025 |
Publication Date |
2010-11-12 |
| 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 |
194 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
| Call Number |
UA @ lucian @ c:irua:95530 |
Serial |
208 |
| Permanent link to this record |
| |
|
| |
| Author |
Khalil-Allafi, J.; Amin-Ahmadi, B.; Zare, M. |
| Title |
Biocompatibility and corrosion behavior of the shape memory NiTi alloy in the physiological environments simulated with body fluids for medical applications |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
Mat Sci Eng C-Mater |
| Volume |
30 |
Issue |
8 |
Pages |
1112-1117 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Due to unique properties of NiTi shape memory alloys such as high corrosion resistance, biocompatibility, super elasticity and shape memory behavior, NiTi shape memory alloys are suitable materials for medical applications. Although TiO2 passive layer in these alloys can prevent releasing of nickel to the environment, high nickel content and stability of passive layer in these alloys are very debatable subjects. In this study a NiTi shape memory alloy with nominal composition of 50.7 atom% Ni was investigated by corrosion tests. Electrochemical tests were performed in two physiological environments of Ringer solution and NaCl 0.9% solution. Results indicate that the breakdown potential of the NiTi alloy in NaCl 0.9% solution is higher than that in Ringer solution. The results of Scanning Electron Microscope (SEM) reveal that low pitting corrosion occurred in Ringer solution compared with NaCl solution at potentiostatic tests. The pH value of the solutions increases after the electrochemical tests. The existence of hydride products in the X-ray diffraction analysis confirms the decrease of the concentration of hydrogen ion in solutions. Topographical evaluations show that corrosion products are nearly same in all samples. The biocompatibility tests were performed by reaction of mouse fibroblast cells (L929). The growth and development of cells for different times were measured by numbering the cells or statistics investigations. The figures of cells for different times showed natural growth of cells. The different of the cell numbers between the test specimen and control specimen was negligible; therefore it may be concluded that the NiTi shape memory alloy is not toxic in the physiological environments simulated with body fluids. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
| Language |
|
Wos |
000282905600006 |
Publication Date |
2010-06-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0928-4931; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.164 |
Times cited |
34 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 4.164; 2010 IF: 2.180 |
| Call Number |
UA @ lucian @ c:irua:122039 |
Serial |
242 |
| Permanent link to this record |
| |
|
| |
| Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
| Title |
Calorimetric properties of mesoscopic superconducting disks, rings, and cylinders |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
6 |
Pages |
064501,1-064501,10 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The thermal signatures of superconductivity in mesoscopic disks, rings and cylinders are calculated within the Ginzburg-Landau theory. In an applied perpendicular magnetic field H the heat capacity of mesoscopic samples shows a strong dependence on the realized vortex state; discontinuities are found at the critical field for different vorticities, as well as at the superconducting-to-normal state transition. The same applies to the intermediate state of type-I superconductors. Even the subtle changes in the fluxoid distribution inside the sample leave clear signatures on heat capacity, which is particularly useful for fully three-dimensional samples whose interior is often inaccessible by magnetometry. The heat-capacity jump ΔC(H) at the critical temperature exhibits quasiperiodic modulations as a function of magnetic field. In mesoscopic superconducting rings, these oscillations provide calorimetric verification of the Little-Parks effect. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000274998100091 |
Publication Date |
2010-02-01 |
| Series Editor |
|
Series Title |
|
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 |
17 |
Open Access |
|
| Notes |
; We are grateful to O. Bourgeois for useful discussions. This work was supported by the Flemish Science Foundation (FWO-VI), the Interuniversity Attraction Poles (IAP) Program-Belgian State-Belgian Science Policy, ESF-JSPS NES program and the ESF-AQDJJ network. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:81766 |
Serial |
271 |
| Permanent link to this record |
| |
|
| |
| Author |
Kosimov, D.P.; Dzhurakhalov, A.A.; Peeters, F.M. |
| Title |
Carbon clusters: from ring structures to nanographene |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
19 |
Pages |
195414,1-195414,12 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Integrated Molecular Plant Physiology Research (IMPRES); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
The lowest-energy configurations of Cn(n≤55) clusters are obtained using the energy-minimization technique with the conjugate gradient method where a modified Brenner potential is invoked to describe the carbon and hydrocarbon interaction. We found that the ground-state configuration consists of a single ring for small number of C atoms and multiring structures are found with increasing n, which can be in planar, bowl-like or caplike form. Contrary to previous predictions, the binding energy Eb does not show even-odd oscillations and only small jumps are found in the Eb(n) curve as a consequence of specific types of edges or equivalently the number of secondary atoms. We found that hydrogenation of the edge atoms may change the ground-state configuration of the nanocluster. In both cases we determined the magic clusters. Special attention is paid to trigonal and hexagonal shaped carbon clusters and to clusters having a graphenelike configuration. Trigonal clusters are never the ground state while hexagonal-shaped clusters are only the ground state when they have zigzag edges. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000278142000103 |
Publication Date |
2010-05-10 |
| Series Editor |
|
Series Title |
|
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 |
55 |
Open Access |
|
| Notes |
; This work was supported by the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-V1). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:83385 |
Serial |
278 |
| Permanent link to this record |
| |
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| |
| Author |
Li, Y.; Yang, X.-Y.; Tian, G.; Vantomme, A.; Yu, J.; Van Tendeloo, G.; Su, B.-L. |
| Title |
Chemistry of trimethyl aluminum: a spontaneous route to thermally stable 3D crystalline macroporous alumina foams with a hierarchy of pore sizes |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
22 |
Issue |
10 |
Pages |
3251-3258 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A simple and spontaneous one-pot self-formation procedure that is easy to scale up has been developed based on the chemistry of trimethylaluminum (TMA), leading to thermally stable macroporous crystalline alumina with a very unique and unprecedented three-dimensional (3D) hierarchical pore structure consisting of well-defined wormlike mesopores. TMA is the precursor of both product and porogene (viz, two working functions within the same molecule (2 in 1)). The materials obtained have been intensively characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), N2 adsorption−desorption, and mercury porosimetry. The open cagelike macrocavities are self-constructed by mesoporous nanorods (diameter of ca. 40−70 nm), which are themselves formed by a random assembly of fibrous nanoparticles 5−6 nm in size. Optical microscopy (OM) has been used in situ to follow the synthesis procedure, which led to the proposal of the formation mechanism. Methane molecules as porogens, which were instantaneously released because of the fast hydrolysis of the chemical precursor, were the key factor in producing these 3D structures with uniform co-continuous macropores that interconnected directly with the wormlike mesopores. The important characteristic of this procedure is the concurrent formation of a multiscaled porous network. The material exhibits great thermal stability. The hierarchically mesoporous−macroporous Al2O3 obtained is quite attractive for a myriad of applications, from catalysis to biomedicine. The present work illustrates that the one-pot self-formation concept, based on the chemistry of alkyl metals, is a versatile method to design industrially valuable hierarchically porous materials. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000277635000030 |
Publication Date |
2010-04-27 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| 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 |
38 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
| Call Number |
UA @ lucian @ c:irua:82760 |
Serial |
356 |
| Permanent link to this record |
| |
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| |
| Author |
Payette, C.; Amaha, S.; Yu, G.; Gupta, J.A.; Austing, D.G.; Nair, S.V.; Partoens, B.; Tarucha, S. |
| Title |
Coherent level mixing in dot energy spectra measured by magnetoresonant tunneling spectroscopy of vertical quantum dot molecules |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
24 |
Pages |
245310,1-245310,15 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We study by magnetoresonant tunneling spectroscopy single-particle energy spectra of the constituent weakly coupled dots in vertical quantum dot molecules over a wide energy window. The measured energy spectra are well modeled by calculated spectra for dots with in-plane confinement potentials that are elliptical and parabolic in form. However, in the regions where two, three, or four single-particle energy levels are naively expected to cross, we observe pronounced level anticrossing behavior and strong variations in the resonant currents as a consequence of coherent mixing induced by small deviations in the nearly ideal dot confinement potentials. We present detailed analysis of the energy spectra, and focus on two examples of three-level crossings whereby the coherent mixing leads to concurrent suppression and enhancement of the resonant currents when the anticrossing levels are minimally separated. The suppression of resonant current is of particular interest since it is a signature of dark state formation due to destructive interference. We also describe in detail and compare two measurement strategies to reliably extract the resonant currents required to characterize the level mixing. |
| 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 |
000278606100003 |
Publication Date |
2010-06-10 |
| 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 |
6 |
Open Access |
|
| Notes |
; We thank A. Bezinger, D. Roth, and M. Malloy for assistance with some of the processing, and K. Ono, T. Kodera, T. Hatano, Y. Tokura, M. Stopa, M. Hilke, G.C. Aers, M. Korkusinski, and R. M. Abolfath for useful discussions. Part of this work is supported by NSERC (Discovery Grant No. 208201), Flemish Science Foundation (FWO-VI), Grant-in-Aid for Scientific Research S (Grant No. 191040070), B (Grant No. 18340081), and by Special Coordination Funds for Promoting Science and Technology, and MEXT. S.T. acknowledges support from QuEST program (BAA-0824). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:83095 |
Serial |
379 |
| Permanent link to this record |
| |
|
| |
| Author |
Wendelen, W.; Dzhurakhalov, A.A.; Peeters, F.M.; Bogaerts, A. |
| Title |
Combined molecular dynamics: continuum study of phase transitions in bulk metals under ultrashort pulsed laser irradiation |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| Volume |
114 |
Issue |
12 |
Pages |
5652-5660 |
| Keywords |
A1 Journal article; Integrated Molecular Plant Physiology Research (IMPRES); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
The phase transition processes induced by ultrashort, 100 fs pulsed laser irradiation of Au, Cu, and Ni are studied by means of a combined atomistic-continuum approach. A moderately low absorbed laser fluence range, from 200 to 600 J/m2 is considered to study phase transitions by means of a local and a nonlocal order parameter. At low laser fluences, the occurrence of layer-by-layer evaporation has been observed, which suggests a direct solid to vapor transition. The calculated amount of molten material remains very limited under the conditions studied, especially for Ni. Therefore, our results show that a kinetic equation that describes a direct solid to vapor transition might be the best approach to model laser-induced phase transitions by continuum models. Furthermore, the results provide more insight into the applicability of analytical superheating theories that were implemented in continuum models and help the understanding of nonequilibrium phase transitions. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000275855600044 |
Publication Date |
2010-01-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.536 |
Times cited |
2 |
Open Access |
|
| Notes |
; A.D. gratefully acknowledges Professor M. Hot (ULB, Brussels) for the basic MD-code that was modified further for the laser-induced melting processes. W.W, and A.D. are thankful to Professor L.V. Zhigilei for useful discussions and advices. The calculations were performed on the CALCUA computing facility of the University of Antwerp. This work was supported by the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 4.536; 2010 IF: 4.524 |
| Call Number |
UA @ lucian @ c:irua:81391 |
Serial |
402 |
| Permanent link to this record |
| |
|
| |
| Author |
Piacente, G.; Hai, G.Q.; Peeters, F.M. |
| Title |
Continuous structural transitions in quasi-one-dimensional classical Wigner crystals |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
2 |
Pages |
|
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We study the structural phase transitions in confined systems of strongly interacting particles. We consider infinite quasi-one-dimensional systems with different pairwise repulsive interactions in the presence of an external confinement following a power law. Within the framework of Landaus theory, we find the necessary conditions to observe continuous transitions and demonstrate that the only allowed continuous transition is between the single- and the double-chain configurations and that it only takes place when the confinement is parabolic. We determine analytically the behavior of the system at the transition point and calculate the critical exponents. Furthermore, we perform Monte Carlo simulations and find a perfect agreement between theory and numerics. |
| 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 |
000274002100035 |
Publication Date |
2010-01-19 |
| 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 |
37 |
Open Access |
|
| Notes |
; The authors acknowledge FAPESP and CNPq (Brazil), the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl) (Belgium) for financial support. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:81243 |
Serial |
493 |
| Permanent link to this record |
| |
|
| |
| Author |
Yang, C.H.; Peeters, F.M.; Xu, W. |
| Title |
Density of states and magneto-optical conductivity of graphene in a perpendicular magnetic field |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
20 |
Pages |
205428 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The density of states (DOS) and the optical conductivity of graphene is calculated in the presence of a perpendicular magnetic field and where scattering on charged and short-range impurities is included. The standard Kubo formula is employed where the self-energy induced by impurity scattering and the Green's function are calculated self-consistently including inter-Landau level (LL) coupling and screening effects. It is found that the scattering from those two types of impurities results in a symmetric LL broadening and asymmetric inter-LL coupling renormalizes the LL positions to lower energy. The peak position and intensity of the magneto-optical conductivity depends on the filling factor and the broadened DOS. Good agreement is found with recent cyclotron resonance measurements. |
| Address |
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| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000284400700003 |
Publication Date |
2010-11-18 |
| 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 |
39 |
Open Access |
|
| Notes |
; This work was supported by the National Natural Science Foundation of China under Grant No. 10804053, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the Chinese Academy of Sciences and Department of Science and Technology of Yunnan Province. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:95543 |
Serial |
641 |
| Permanent link to this record |
| |
|
| |
| Author |
Yiu, H.H.P.; Niu, H.-jun; Biermans, E.; Van Tendeloo, G.; Rosseinsky, M.J. |
| Title |
Designed multifunctional nanocomposites for biomedical applications |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
| Volume |
20 |
Issue |
10 |
Pages |
1599-1609 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The assembly of multifunctional nanocomposite materials is demonstrated by exploiting the molecular sieving property of SBA-16 nanoporous silica and using it as a template material. The cages of the pore networks are used to host iron oxide magnetic nanoparticles, leaving a pore volume of 0.29 cm3 g-1 accessible for drug storage. This iron oxide-silica nanocomposite is then functionalized with amine groups. Finally the outside of the particle is decorated with antibodies. Since the size of many protein molecules, including that of antibodies, is too large to enter the pore system of SBA-16, the amine groups inside the pores are preserved for drug binding. This is proven using a fluorescent protein, fluorescein-isothiocyanate-labeled bovine serum albumin (FITC-BSA), with the unreacted amine groups inside the pores dyed with rhodamine B isothiocyanate (RITC). The resulting nanocomposite material offers a dual-targeting drug delivery mechanism, i.e., magnetic and antibody-targeting, while the functionalization approach is extendable to other applications, e.g., fluorescence-magnetic dual-imaging diagnosis. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| Language |
|
Wos |
000278597100008 |
Publication Date |
2010-04-01 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1616-301X;1616-3028; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
56 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 12.124; 2010 IF: 8.508 |
| Call Number |
UA @ lucian @ c:irua:83298 |
Serial |
662 |
| Permanent link to this record |
| |
|
| |
| Author |
Lin, N.S.; Misko, V.R.; Peeters, F.M. |
| Title |
Dynamics of multishell vortex structures in mesoscopic superconducting Corbino disks |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
13 |
Pages |
134504,1-134504,11 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We study the dynamics of vortex shells in mesoscopic superconducting Corbino disks, where vortices form shells as recently observed in micrometer-sized Nb disks. Due to the interplay between the vortex-vortex interaction, the gradient Lorentz force and the (in)commensurability between the numbers of vortices in shells, the process of angular melting of vortex-shell configurations becomes complex. Angular melting can start either from the center of the disk (where the shear stress is maximum) or from its boundary (where the shear stress is minimum) depending on the specific vortex configuration. Furthermore, we found that two kinds of defects can exist in such vortex-shell structures: intrashell and intershell defects. An intrashell defect may lead to an inverse dynamic behavior, i.e., one of the vortex shells under a stronger driving force can rotate slower than the adjacent shell that is driven by a weaker Lorentz force. An intershell defect always locks more than two shells until the gradient of the Lorentz force becomes large enough to break the rigid-body rotation of the locked shells. Such a lock-unlock process leads to hysteresis in the angular velocities of the shells. |
| 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 |
000277207900079 |
Publication Date |
2010-04-02 |
| 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 |
11 |
Open Access |
|
| Notes |
; This work was supported by the “Odysseus” program of the Flemish Government and the Flemish Science Foundation (FWO-V1), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, and the FWO-V1. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:82803 |
Serial |
779 |
| Permanent link to this record |
| |
|
| |
| Author |
Ao, Z.M.; Peeters, F.M. |
| Title |
Electric field activated hydrogen dissociative adsorption to nitrogen-doped graphene |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| Volume |
114 |
Issue |
34 |
Pages |
14503-14509 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Graphane, hydrogenated graphene, was very recently synthesized and predicted to have great potential applications. In this work, we propose a new promising approach for hydrogenation of graphene based on density functional theory (DFT) calculations through the application of a perpendicular electric field after substitutionally doping by nitrogen atoms. These DFT calculations show that the doping by nitrogen atoms into the graphene layer and applying an electrical field normal to the graphene surface induce dissociative adsorption of hydrogen. The dissociative adsorption energy barrier of an H2 molecule on a pristine graphene layer changes from 2.7 to 2.5 eV on N-doped graphene, and to 0.88 eV on N-doped graphene under an electric field of 0.005 au. When increasing the electric field above 0.01 au, the reaction barrier disappears. Therefore, N doping and applying an electric field have catalytic effects on the hydrogenation of graphene, which can be used for hydrogen storage purposes and nanoelectronic applications. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000281129100027 |
Publication Date |
2010-08-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.536 |
Times cited |
110 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 4.536; 2010 IF: 4.524 |
| Call Number |
UA @ lucian @ c:irua:84588 |
Serial |
882 |
| Permanent link to this record |
| |
|
| |
| Author |
Wu, Z.; Peeters, F.M.; Chang, K. |
| Title |
Electron tunneling through double magnetic barriers on the surface of a topological insulator |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
11 |
Pages |
115211-115211,7 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We study electron tunneling through a planar magnetic and electric barrier on the surface of a three-dimensional topological insulator. For the double barrier structures, we find (i) a directional-dependent tunneling which is sensitive to the magnetic field configuration and the electric gate voltage, (ii) a spin rotation controlled by the magnetic field and the gate voltage, (iii) many Fabry-Pérot resonances in the transmission determined by the distance between the two barriers, and (iv) the electrostatic potential can enhance the difference in the transmission between the two magnetization configurations, and consequently lead to a giant magnetoresistance. Points (i), (iii), and (iv) are alike with that in graphene stemming from the same linear-dispersion relations. |
| 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 |
|
| Language |
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Wos |
000282125700002 |
Publication Date |
2010-09-27 |
| 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 |
65 |
Open Access |
|
| Notes |
; This work was supported by the NSF of China, the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:85420 |
Serial |
990 |
| Permanent link to this record |
| |
|
| |
| Author |
Peelaers, H.; Partoens, B.; Peeters, F.M. |
| Title |
Electronic and dynamical properties of Si/Ge core-shell nanowires |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
11 |
Pages |
113411-113411,4 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Full ab initio techniques are applied to study the electronic and dynamical properties of free standing, hydrogen-passivated Si/Ge core-shell nanowires oriented along the [110] direction. All studied wires exhibit a direct band gap and are found to be structurally stable. The different contributions of the core and shell atoms to the phonon spectra are identified. The acoustic phonon velocities and the frequencies of some typical optical modes are compared with those of pure Si and Ge nanowires. These depend either on the concentration or on the type of core material. Optical modes are hardened and longitudinal acoustic velocities are softened with decreasing wire diameter. |
| 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 |
|
| Language |
|
Wos |
000282270000001 |
Publication Date |
2010-09-29 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and NOI-BOF (University of Antwerp). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:85421 |
Serial |
995 |
| Permanent link to this record |
| |
|
| |
| Author |
Hernández-Nieves, A.D.; Partoens, B.; Peeters, F.M. |
| Title |
Electronic and magnetic properties of superlattices of graphene/graphane nanoribbons with different edge hydrogenation |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
16 |
Pages |
165412-165412,9 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Zigzag graphene nanoribbons patterned on graphane are studied using spin-polarized ab initio calculations. We found that the electronic and magnetic properties of the graphene/graphane superlattice strongly depends on the degree of hydrogenation at the interfaces between the two materials. When both zigzag interfaces are fully hydrogenated, the superlattice behaves like a freestanding zigzag graphene nanoribbon, and the magnetic ground state is antiferromagnetic. When one of the interfaces is half hydrogenated, the magnetic ground state becomes ferromagnetic, and the system is very close to being a half metal with possible spintronics applications whereas the magnetic ground state of the superlattice with both interfaces half hydrogenated is again antiferromagnetic. In this last case, both edges of the graphane nanoribbon also contribute to the total magnetization of the system. All the spin-polarized ground states are semiconducting, independent of the degree of hydrogenation of the interfaces. The ab initio results are supplemented by a simple tight-binding analysis that captures the main qualitative features. Our ab initio results show that patterned hydrogenation of graphene is a promising way to obtain stable graphene nanoribbons with interesting technological applications. |
| 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 |
|
| Language |
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Wos |
000282569500011 |
Publication Date |
2010-10-07 |
| Series Editor |
|
Series Title |
|
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 |
46 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), and the collaborative project FWO-MINCyT (FW/08/01). A. D. H. acknowledges also support from ANPCyT (under Grant No. PICT2008-2236) ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:85030 |
Serial |
996 |
| Permanent link to this record |
| |
|
| |
| Author |
Verbeeck, J.; Bals, S.; Lamoen, D.; Luysberg, M.; Huijben, M.; Rijnders, G.; Brinkman, A.; Hilgenkamp, H.; Blank, D.H.A.; Van Tendeloo, G. |
| Title |
Electronic reconstruction at n-type SrTiO3/LaAlO3 interfaces |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
8 |
Pages |
085113,1-085113,6 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Electron-energy-loss spectroscopy (EELS) is used to investigate single layers of LaAlO3 grown on SrTiO3 having an n-type interface as well as multilayers of LaAlO3 and SrTiO3 in which both n- and p-type interfaces occur. Only minor changes in Ti valence at the n-type interface are observed. This finding seems to contradict earlier experiments for other SrTiO3/LaAlO3 systems where large deviations in Ti valency were assumed to be responsible for the conductivity of these interfaces. Ab initio calculations have been carried out in order to interpret our EELS results. Using the concept of Bader charges, it is demonstrated that the so-called polar discontinuity is mainly resolved by lattice distortions and to a far lesser extent by changes in valency for both single layer and multilayer geometries. |
| 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 |
000275053300040 |
Publication Date |
2010-02-18 |
| Series Editor |
|
Series Title |
|
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 |
25 |
Open Access |
|
| Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:81768UA @ admin @ c:irua:81768 |
Serial |
1005 |
| Permanent link to this record |
| |
|
| |
| Author |
Kishore, V.V.R.; Partoens, B.; Peeters, F.M. |
| Title |
Electronic structure and optical absorption of GaAs/AlxGa1-xAs and AlxGa1-xAs/GaAs core-shell nanowires |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
23 |
Pages |
235425-235425,9 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The electronic structure of GaAs/AlxGa1−xAs and AlxGa1−xAs/GaAs core-shell nanowires grown in the [001] direction is studied. The k⋅p method with the 6×6 Kohn-Lüttinger Hamiltonian, taking into account the split-off band is used. The variation in the energy level dispersion, the spinor contribution to the ground state and the optical interband absorption are studied. For some range of parameters the top of the valence band exhibits a camelback structure which results in an extra peak in the optical absorption. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000286769100008 |
Publication Date |
2010-12-14 |
| 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 |
23 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:86911 |
Serial |
1010 |
| Permanent link to this record |
| |
|
| |
| Author |
Misko, V.R.; Bothner, D.; Kemmler, M.; Kleiner, R.; Koelle, D.; Peeters, F.M.; Nori, F. |
| Title |
Enhancing the critical current in quasiperiodic pinning arrays below and above the matching magnetic flux |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
18 |
Pages |
184512-184512,7 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Quasiperiodic pinning arrays, as recently demonstrated theoretically and experimentally using a fivefold Penrose tiling, can lead to a significant enhancement of the critical current Ic as compared to traditional regular pinning arrays. However, while regular arrays showed only a sharp peak in Ic(Φ) at the matching flux Φ1 and quasiperiodic arrays provided a much broader maximum at Φ<Φ1, both types of pinning arrays turned out to be inefficient for fluxes larger than Φ1. We demonstrate theoretically and experimentally the enhancement of Ic(Φ) for Φ>Φ1 by using non-Penrose quasiperiodic pinning arrays. This result is based on a qualitatively different mechanism of flux pinning by quasiperiodic pinning arrays and could be potentially useful for applications in superconducting microelectronic devices operating in a broad range of magnetic fields. |
| 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 |
000283923400006 |
Publication Date |
2010-11-08 |
| 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 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
33 |
Open Access |
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| Notes |
; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, the FWO-Vl, and by the DFG via SFB/TRR21. V. R. M. is grateful to the FWO-Vl for the support of the research stay at the DML (ASI, RIKEN), and to F. N. for hospitality. M. K. gratefully acknowledges support from the Carl-Zeiss-Stiftung, and D. B. from the Evangelisches Studienwerk e.V. Villigst. F. N. acknowledges partial support from the Laboratory of Physical Sciences, National Security Agency, Army Research Office, DARPA, AFOSR, National Science Foundation under Grant No. 0726909, JSPS-RFBR under Contract No. 09-02-92114, Grant-in-Aid for Scientific Research (S), MEXT Kakenhi on Quantum Cybernetics, and Funding Program for Innovative R&D on S&T (FIRST). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:85800 |
Serial |
1066 |
| Permanent link to this record |
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| |
| Author |
Barbier, M.; Vasilopoulos, P.; Peeters, F.M. |
| Title |
Extra Dirac points in the energy spectrum for superlattices on single-layer graphene |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
7 |
Pages |
075438,1-075438,7 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the emergence of extra Dirac points in the electronic structure of a periodically spaced barrier system, i.e., a superlattice, on single-layer graphene, using a Dirac-type Hamiltonian. Using square barriers allows us to find analytic expressions for the occurrence and location of these new Dirac points in k space and for the renormalization of the electron velocity near them in the low-energy range. In the general case of unequal barrier and well widths the new Dirac points move away from the Fermi level and for given heights of the potential barriers there is a minimum and maximum barrier width outside of which the new Dirac points disappear. The effect of these extra Dirac points on the density of states and on the conductivity is investigated. |
| 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 |
000274998200133 |
Publication Date |
2010-02-25 |
| 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 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
211 |
Open Access |
|
| Notes |
; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the Brazilian Council for Research (CNPq), and the Canadian NSERC Grant No. OGP0121756. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:81767 |
Serial |
1159 |
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| Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
| Title |
Fabry-Pérot resonances in graphene microstructures: influence of a magnetic field |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
11 |
Pages |
115417-115417,12 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Fabry-Pérot resonances in the transmission through single and double, graphene-based barriers (of height V) and wells are investigated and their dependence on an applied perpendicular magnetic field. For rectangular barriers the conductance decreases with increasing magnetic field while the resonances weaken (become more pronounced) with increasing magnetic field for EF<V (EF>V). The position of the resonances exhibit a linear shift with magnetic field which move to lower (higher) energy for EF<V (EF>V). Compared to semielliptic- or Gaussian-shaped barriers they show a smaller number of resonances in the absence of a magnetic field and an overall lower conductance but the resonant structure is more pronounced. The conductance of asymmetric double barriers show two major regions of resonances while the symmetric ones show one, that of three asymmetric barriers three, and so on. |
| 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 |
000281723100007 |
Publication Date |
2010-09-10 |
| 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 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
74 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the Canadian NSERC under Grant No. OGP0121756. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:84871 |
Serial |
1167 |
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| Author |
Xu, T.; Nys, J.-P.; Addad, A.; Lebedev, O.I.; Urbieta, A.; Salhi, B.; Berthe, M.; Grandidier, B.; Stievenard, D. |
| Title |
Faceted sidewalls of silicon nanowires: Au-induced structural reconstructions and electronic properties |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
11 |
Pages |
115403,1-115403,10 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Si nanowires with a ⟨111⟩ orientation, synthesized by vapor-liquid-solid process with low silane partial pressure reactant and gold as the catalyst, are known to exhibit sawtooth facets containing gold adsorbates. We report herein the study of the nanowire morphology by means of transmission electron microscopy and scanning tunneling microscopy. The nanowires consist of faceted sidewalls. The number of the sidewalls changes from 12 to 6 along the growth axis, giving rise to nanowires with an irregular hexagonal cross section at their base. The sidewalls are covered with Au-rich clusters. Their facets also exhibit atomic structures that reveal the presence of gold, resulting from the diffusion of gold during the growth. Based on these observations, the tapering of the nanowire is found to be related to two contributions: the reduction in the catalyst particle size during the growth and lateral overgrowth from the direct incorporation of Si species onto the nanowire sidewalls. Because the rearrangement of atoms at surfaces and interfaces might affect the growth kinetics, the trigonal symmetry as well as the higher lateral growth rate on the widest sidewalls are explained from the existence of an interfacial atomic structure with two inequivalent parts in the unit cell. Finally, spectroscopic measurements were performed on the major facets and revealed a metallic behavior at 77 K. |
| 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 |
000276248800116 |
Publication Date |
2010-03-03 |
| 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 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
42 |
Open Access |
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| Notes |
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Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:82273 |
Serial |
1168 |
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| Author |
Zelaya, E.; Schryvers, D. |
| Title |
FCC surface precipitation in Cu-Zn-Al after low angle GA+ ion irradiation |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Materials transactions |
Abbreviated Journal |
Mater Trans |
| Volume |
51 |
Issue |
12 |
Pages |
2177-2180 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The precipitation of a disordered FCC surface structure after low angle Ga+ ion irradiation during focused ion beam thinning of a B2 Cu-Zn-Al alloy with e/a=1.48 is reported. Conventional as well as high-resolution transmission electron microscopy techniques reveal FCC layers on both sides of the thinned sample. The occurrence of this structure is attributed to disordering and dezincification of the alloy resulting from the sputtering process during the irradiation. Changes in crystallographic sample orientation with respect to the incoming ion beam do not have a significant effect on the appearance of the FCC surface structure. |
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Thesis |
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Place of Publication |
Sendai |
Editor |
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| Language |
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Wos |
000287390300009 |
Publication Date |
2010-11-25 |
| 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 |
1347-5320;1345-9678; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
0.713 |
Times cited |
2 |
Open Access |
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| Notes |
Bof; Fwo |
Approved |
Most recent IF: 0.713; 2010 IF: 0.787 |
| Call Number |
UA @ lucian @ c:irua:85997 |
Serial |
1175 |
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| Author |
Leenaerts, O.; Peelaers, H.; Hernández-Nieves, A.D.; Partoens, B.; Peeters, F.M. |
| Title |
First-principles investigation of graphene fluoride and graphane |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
82 |
Issue |
19 |
Pages |
195436,1-195436,6 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Different stoichiometric configurations of graphane and graphene fluoride are investigated within density-functional theory. Their structural and electronic properties are compared, and we indicate the similarities and differences among the various configurations. Large differences between graphane and graphene fluoride are found that are caused by the presence of charges on the fluorine atoms. A configuration that is more stable than the boat configuration is predicted for graphene fluoride. We also perform GW calculations for the electronic band gap of both graphene derivatives. These band gaps and also the calculated Youngs moduli are at variance with available experimental data. This might indicate that the experimental samples contain a large number of defects or are only partially covered with H or F. |
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Place of Publication |
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Editor |
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Wos |
000284399200004 |
Publication Date |
2010-11-18 |
| 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 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
367 |
Open Access |
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| Notes |
; This work was supported by the Flemish Science Foundation (FWO-V1), the NOI-BOF of the University of Antwerp, the Belgian Science Policy (IAP), and the collaborative project FWO-MINCyT (Grant No. FW/08/01). A.D.H. also acknowledges support from ANPCyT (Grant No. PICT 2008-2236). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:86916 |
Serial |
1212 |
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| Author |
Goffin, A.-L.; Duquesne, E.; Raquez, J.-M.; Miltner, H.E.; Ke, X.; Alexandre, M.; Van Tendeloo, G.; van Mele, B.; Dubois, P. |
| Title |
From polyester grafting onto POSS nanocage by ring-opening polymerization to high performance polyester/POSS nanocomposites |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
| Volume |
20 |
Issue |
42 |
Pages |
9415-9422 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Polyester-grafted polyhedral oligomeric silsesquioxane (POSS) nanohybrids selectively produced by ring-opening polymerization of ε-caprolactone and L,L-lactide (A.-L. Goffin, E. Duquesne, S. Moins, M. Alexandre, Ph. Dubois, Eur. Polym. Journal, 2007, 43, 4103) were studied as masterbatches by melt-blending within their corresponding commercial polymeric matrices, i.e., poly(ε-caprolactone) (PCL) and poly(L,L-lactide) (PLA). For the sake of comparison, neat POSS nanoparticles were also dispersed in PCL and PLA. The objective was to prepare aliphatic polyester-based nanocomposites with enhanced crystallization behavior, and therefore, enhanced thermo-mechanical properties. Wide-angle X-ray scattering and transmission electron microscopy attested for the dispersion of individualized POSS nanoparticles in the resulting nanocomposite materials only when the polyester-grafted POSS nanohybrid was used as a masterbatch. The large impact of such finely dispersed (grafted) nanoparticles on the crystallization behavior for the corresponding polyester matrices was noticed, as evidenced by differential scanning calorimetry analysis. Indeed, well-dispersed POSS nanoparticles acted as efficient nucleating sites, significantly increasing the crystallinity degree of both PCL and PLA matrices. As a result, a positive impact on thermo-mechanical properties was highlighted by dynamic mechanical thermal analysis. |
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Place of Publication |
Cambridge |
Editor |
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| Language |
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Wos |
000283264500017 |
Publication Date |
2010-06-03 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0959-9428;1364-5501; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
42 |
Open Access |
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| Notes |
Fwo; Iap-6 |
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:85784 |
Serial |
1284 |
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| Author |
Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Shpanchenko, R.V.; Geibel, C.; Rosner, H. |
| Title |
Frustrated square lattice with spatial anisotropy: crystal structure and magnetic properties of PbZnVO(PO4)2 |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
81 |
Issue |
17 |
Pages |
174424,1-174424,13 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Crystal structure and magnetic properties of the layered vanadium phosphate PbZnVO(PO4)2 are studied using x-ray powder diffraction, magnetization and specific-heat measurements, as well as band-structure calculations. The compound resembles AA′VO(PO4)2 vanadium phosphates and fits to the extended frustrated square-lattice model with the couplings J1, J1′ between nearest neighbors and J2, J2′ between next-nearest neighbors. The temperature dependence of the magnetization yields estimates of averaged nearest-neighbor and next-nearest-neighbor couplings, J̅ 1≃−5.2 K and J̅ 2≃10.0 K, respectively. The effective frustration ratio α=J̅ 2/J̅ 1 amounts to −1.9 and suggests columnar antiferromagnetic ordering in PbZnVO(PO4)2. Specific-heat data support the estimates of J̅ 1 and J̅ 2 and indicate a likely magnetic ordering transition at 3.9 K. However, the averaged couplings underestimate the saturation field, thus pointing to the spatial anisotropy of the nearest-neighbor interactions. Band-structure calculations confirm the identification of ferromagnetic J1, J1′ and antiferromagnetic J2, J2′ in PbZnVO(PO4)2 and yield (J1′−J1)≃1.1 K in excellent agreement with the experimental value of 1.1 K, deduced from the difference between the expected and experimentally measured saturation fields. Based on the comparison of layered vanadium phosphates with different metal cations, we show that a moderate spatial anisotropy of the frustrated square lattice has minor influence on the thermodynamic properties of the model. We discuss relevant geometrical parameters, controlling the exchange interactions in these compounds and propose a strategy for further design of strongly frustrated square-lattice materials. |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000278141600082 |
Publication Date |
2010-05-25 |
| 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 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
27 |
Open Access |
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| Notes |
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Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
| Call Number |
UA @ lucian @ c:irua:83384 |
Serial |
1294 |
| Permanent link to this record |
