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Records |
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Author |
Zha, G.-Q.; Milošević, M.V.; Zhou, S.-P.; Peeters, F.M. |
| |
Title |
Influence of impurities and surface defects on the flux-induced current in mesoscopic d-wave superconducting loops |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
84 |
Issue |
13 |
Pages |
132501-132501,4 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We investigated the magnetic flux dependence of the supercurrent in mesoscopic d-wave superconducting loops, containing impurities and surface defects, by numerically solving the Bogoliubovde Gennes equations self-consistently. In the presence of impurities, bound states arise close to the Fermi energy. In the case of a single impurity, the flux-induced current is found to be suppressed. This can be different when more impurities are introduced in the sample due to the quantum interference effect, which depends sensitively on the relative position between the impurities. We further analyze the effect of small surface defects at the inner or outer edge of the loop, and show that indentation and bulge defects have pronounced and different effects on the supercurrent. |
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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 |
000295713600002 |
Publication Date  |
2011-10-07 |
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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 |
13 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), by Belgian Science Policy (IAP), by National Science Foundation of China (Grant Nos. 10904089 and 60971053), and by research funds under Grant Nos. 20093108120005, S30105, 09JC1406000, and 10zz63. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
| |
Call Number |
UA @ lucian @ c:irua:92811 |
Serial |
1623 |
| Permanent link to this record |
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Author |
Smeulders, G.; van Oers, C.; Van Havenbergh, K.; Houthoofd, K.; Mertens, M.; Martens, J.A.; Bals, S.; Maes, B.U.W.; Meynen, V.; Cool, P. |
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Title |
Smart heating profiles for the synthesis of benzene bridged periodic mesoporous organosilicas |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
| |
Volume |
175 |
Issue |
|
Pages |
585-591 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY) |
| |
Abstract |
In this study the effects of the heating rate and heating time on the formation of crystal-like benzene bridged periodic mesoporous organosilicas (PMOs) are investigated. The time needed to heat up an autoclave during the hydrothermal treatment has shown to be crucial in the synthesis of PMOs, while the total duration of heating gave rise to only minor differences. By choosing a smart heating profile, superior PMO materials can be obtained in a short time. Different heating profiles in a range from one minute to one hour are adopted by microwave equipment and compared with conventional heating methods. The heating rate has a large influence on the porosity characteristics and the uniformity of the obtained particles. Moreover, two new alternative synthetic strategies to adopt the smart heating profile are presented, in order to give some possible solutions for the expensive microwave equipment. |
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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 |
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Wos |
000297875900069 |
Publication Date |
2011-10-07 |
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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 |
1385-8947; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.216 |
Times cited |
7 |
Open Access |
|
| |
Notes |
Fwo; Goa-Bof |
Approved |
Most recent IF: 6.216; 2011 IF: 3.461 |
| |
Call Number |
UA @ lucian @ c:irua:93630 |
Serial |
3044 |
| Permanent link to this record |
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Author |
Rouchon, V.; Pellizzi, E.; Duranton, M.; Vanmeert, F.; Janssens, K. |
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Title |
Combining XANES, ICP-AES, and SEM/EDS for the study of phytate chelating treatments used on iron gall ink damaged manuscripts |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
| |
Volume |
26 |
Issue |
12 |
Pages |
2434-2441 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| |
Abstract |
Many historical documents written with iron gall inks are endangered by the corrosive effects of these inks. In this work, a combination of complementary analytical methods was used for the first time in order to study the phytate process which is used in conservation studios to stabilize damaged manuscripts. This process consists of an antioxidant treatment performed by means of a calcium phytate (CP) solution, followed by a deacidification treatment performed with a calcium carbonate (CC) solution. The antioxidant treatment capitalizes on the properties of myo-inositol hexaphosphoric acid (phytic acid) that inhibits iron through chelation. In order to use relatively low acidic solutions, the pH of the CP solution is increased up to values between 5 and 6, which is in the range of the CP precipitation threshold. This study was performed on laboratory samples made of paper impregnated with iron gall ink and artificially aged in climatic chambers. It aims to investigate how the CP precipitate impacts the efficiency of the treatment. Side effects, such as elemental losses and deposits, were measured by means of several analytical techniques (FeK Edge XANES, SEM/EDS, and ICP-AES). These measurements were crosschecked with a ready to use colour spot test made of bathophenanthroline impregnated paper. It appeared that the CP treatment should necessarily be followed by the deacidification treatment in order to achieve long term stability. The precipitation of CP in the treating solution does finally not impact the efficiency of the treatment despite the fact that it should theoretically lower the availability of phytate to chelate iron. A scenario is proposed to explain this point. |
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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 |
000297030400008 |
Publication Date |
2011-10-06 |
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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 |
0267-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.379 |
Times cited |
10 |
Open Access |
|
| |
Notes |
; This research was funded by SOLEIL (proposals 20060396 and 20080761) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. We are thankful to the paper conservator students of the Institut National du Patrimoine who were involved in some of the sample preparations, and to Dr Dominique Thiaudiere and Dr Solenn Reguer for their assistance and help during the experiments performed at SOLEIL beamline “DIFFABS”. ; |
Approved |
Most recent IF: 3.379; 2011 IF: 3.220 |
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Call Number |
UA @ admin @ c:irua:93845 |
Serial |
5527 |
| Permanent link to this record |
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Author |
Bittencourt, C.; Navio, C.; Nicolay, A.; Ruelle, B.; Godfroid, T.; Snyders, R.; Colomer, J.-F.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Suarez-Martinez, I.; Ewels, C.P. |
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Title |
Atomic oxygen functionalization of vertically aligned carbon nanotubes |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
115 |
Issue |
42 |
Pages |
20412-20418 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Vertically aligned multiwalled carbon nanotubes (v-MWCNTs) are functionalized using atomic oxygen generated in a microwave plasma. X-ray photoelectron spectroscopy depth profile analysis shows that the plasma treatment effectively grafts oxygen exclusively at the v-MWCNT tips. Electron microscopy shows that neither the vertical alignment nor the structure of v-MWCNTs were affected by the plasma treatment. Density functional calculations suggest assignment of XPS C 1s peaks at 286.6 and 287.5 eV, to epoxy and carbonyl functional groups, respectively. |
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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, D.C. |
Editor |
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Language |
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Wos |
000296205600009 |
Publication Date |
2011-10-04 |
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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 |
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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 |
31 |
Open Access |
|
| |
Notes |
Iap |
Approved |
Most recent IF: 4.536; 2011 IF: 4.805 |
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Call Number |
UA @ lucian @ c:irua:91890 |
Serial |
174 |
| Permanent link to this record |
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Author |
Zarenia, M.; Pereira, J.M.; Farias, G.A.; Peeters, F.M. |
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Title |
Chiral states in bilayer graphene : magnetic field dependence and gap opening |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
84 |
Issue |
12 |
Pages |
125451-125451,13 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
At the interface of electrostatic potential kink profiles, one-dimensional chiral states are found in bilayer graphene (BLG). Such structures can be created by applying an asymmetric potential to the upper and the lower layers of BLG. We found the following: (i) due to the strong confinement by the single kink profile, the unidirectional states are only weakly affected by a magnetic field; (ii) increasing the smoothness of the kink potential results in additional bound states, which are topologically different from those chiral states; and (iii) in the presence of a kink-antikink potential, the overlap between the oppositely moving chiral states results in the appearance of crossing and anticrossing points in the energy spectrum. This leads to the opening of tunable minigaps in the spectrum of the unidirectional topological states. |
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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 |
000295484300016 |
Publication Date |
2011-09-30 |
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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 |
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Series Issue |
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Edition |
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
50 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CONGRAN), the Brazilian agency CNPq (Pronex), and the bilateral projects between Flanders and Brazil and the collaboration project FWO-CNPq. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
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Call Number |
UA @ lucian @ c:irua:92915 |
Serial |
358 |
| Permanent link to this record |
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Author |
Korneychik, O.E.; Batuk, M.; Abakumov, A.M.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Pokholok, K.V.; Filimonov, D.S.; Antipov, E.V. |
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Title |
Pb2.85Ba2.15Fe4SnO13 : a new member of the AnBnO3n-2 anion-deficient perovskite-based homologous series |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
184 |
Issue |
12 |
Pages |
3150-3157 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Pb2.85Ba2.15Fe4SnO13, a new n=5 member of the anion-deficient perovskite based AnBnO3n−2 (A=Pb, Ba, B=Fe, Sn) homologous series, was synthesized by the solid state method. The crystal structure of Pb2.85Ba2.15Fe4SnO13 was investigated using a combination of neutron powder diffraction, electron diffraction, high angle annular dark field scanning transmission electron microscopy and Mössbauer spectroscopy. It crystallizes in the Ammm space group with unit cell parameters a=5.7990(1) Å, b=4.04293(7) Å and c=26.9561(5) Å. The Pb2.85Ba2.15Fe4SnO13 structure consists of quasi two-dimensional perovskite blocks separated by 1/2[110](1̄01)p crystallographic shear (CS) planes. The corner-sharing FeO6 octahedra at the CS planes are transformed into edge-sharing FeO5 distorted tetragonal pyramids. The octahedral positions in the perovskite blocks between the CS planes are jointly taken up by Fe and Sn, with a preference of Sn towards the position at the center of the perovskite block. The chains of FeO5 pyramids and (Fe,Sn)O6 octahedra of the perovskite blocks delimit six-sided tunnels at the CS planes occupied by double chains of Pb atoms. The compound is antiferromagnetically ordered below TN=368±15 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 |
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Language |
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Wos |
000297662500003 |
Publication Date |
2011-09-30 |
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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 |
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Series Issue |
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Edition |
|
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.299 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.299; 2011 IF: 2.159 |
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Call Number |
UA @ lucian @ c:irua:94013 |
Serial |
3550 |
| Permanent link to this record |
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Author |
Belik, A.A.; Abakumov, A.M.; Tsirlin, A.A.; Hadermann, J.; Kim, J.; Van Tendeloo, G.; Takayama-Muromachi, E. |
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Title |
Article Structure and magnetic properties of BiFe0.75Mn0.25O3 perovskite prepared at ambient and high pressure |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| |
Volume |
23 |
Issue |
20 |
Pages |
4505-4514 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Solid solutions of BiFe1xMnxO3 (0.0 ≤ x ≤ 0.4) were prepared at ambient pressure and at 6 GPa. The ambient-pressure (AP) phases crystallize in space group R3c similarly to BiFeO3. The high-pressure (HP) phases crystallize in space group R3c for x = 0.05 and in space group Pnma for 0.15 ≤ x ≤ 0.4. The structure of HP-BiFe0.75Mn0.25O3 was investigated using synchrotron X-ray powder diffraction, electron diffraction, and transmission electron microscopy. HP-BiFe0.75Mn0.25O3 has a PbZrO3-related √2ap × 4ap × 2√2ap (ap is the parameter of the cubic perovskite subcell) superstructure with a = 5.60125(9) Å, b = 15.6610(2) Å, and c = 11.2515(2) Å similar to that of Bi0.82La0.18FeO3. A remarkable feature of this structure is the unconventional octahedral tilt system, with the primary ab0a tilt superimposed on pairwise clockwise and counterclockwise rotations around the b-axis according to the oioi sequence (o stands for out-of-phase tilt, and i stands for in-phase tilt). The (FeMn)O6 octahedra are distorted, with one longer metaloxygen bond (2.222.23 Å) that can be attributed to a compensation for covalent BiO bonding. Such bonding results in the localization of the lone electron pair on Bi3+ cations, as confirmed by electron localization function analysis. The relationship between HP-BiFe0.75Mn0.25O3 and antiferroelectric structures of PbZrO3 and NaNbO3 is discussed. On heating in air, HP-BiFe0.75Mn0.25O3 irreversibly transforms to AP-BiFe0.75Mn0.25O3 starting from about 600 K. Both AP and HP phases undergo an antiferromagnetic ordering at TN ≈ 485 and 520 K, respectively, and develop a weak net magnetic moment at low temperatures. Additionally, ceramic samples of AP-BiFe0.75Mn0.25O3 show a peculiar phenomenon of magnetization reversal. |
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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, D.C. |
Editor |
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Language |
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Wos |
000295897400015 |
Publication Date |
2011-09-29 |
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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 |
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Series Issue |
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Edition |
|
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
9.466 |
Times cited |
57 |
Open Access |
|
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Notes |
|
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
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Call Number |
UA @ lucian @ c:irua:93581 |
Serial |
151 |
| Permanent link to this record |
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Author |
Tirumalasetty, G.K.; van Huis, M.A.; Fang, C.M.; Xu, Q.; Tichelaar, F.D.; Hanlon, D.N.; Sietsma, J.; Zandbergen, H.W. |
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Title |
Characterization of NbC and (Nb, Ti)N nanoprecipitates in TRIP assisted multiphase steels |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
| |
Volume |
59 |
Issue |
19 |
Pages |
7406-7415 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Multiphase steels utilising composite strengthening may be further strengthened via grain refinement or precipitation by the addition of microalloying elements. In this study a Nb microalloyed steel comprising martensite, bainite and retained austenite has been studied. By means of transmission electron microscopy (TEM) we have investigated the size distribution and the structural properties of (Nb, Ti)N and NbC precipitates, their occurrence in the various steel phases, and their relationship with the Fe matrix. (Nb, Ti)N precipitates were found in ferrite, martensite, and bainite, while NbC precipitates were found only in ferrite. All NbC precipitates were found to be small (520 nm in size) and to have a face centred cubic (fcc) crystal structure with lattice parameter a = 4.36 ± 0.05 Å. In contrast, the (Nb, Ti)N precipitates were found to have a broader size range (5150 nm) and to have a fcc crystal structure with lattice parameter a = 8.09 ± 0.05 Å. While the NbC precipitates were found to be randomly oriented, the (Nb, Ti)N precipitates have a well-defined NishiyamaWasserman orientation relationship with the ferrite matrix. An analysis of the lattice mismatch suggests that the latter precipitates have a high potential for effective strengthening. Density functional theory calculations were performed for various stoichiometries of NbCx and NbxTiyNz phases and the comparison with experimental data indicates that both the carbides and nitrides are deficient in C and N content. |
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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 |
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Wos |
000296405200026 |
Publication Date |
2011-09-29 |
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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 |
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Series Issue |
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Edition |
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ISSN |
1359-6454; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.301 |
Times cited |
58 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 5.301; 2011 IF: 3.755 |
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Call Number |
UA @ lucian @ c:irua:93297 |
Serial |
328 |
| Permanent link to this record |
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Author |
Kalkert, C.; Krisponeit, J.-O.; Esseling, M.; Lebedev, O.I.; Moshnyaga, V.; Damaschke, B.; Van Tendeloo, G.; Samwer, K. |
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Title |
Resistive switching at manganite/manganite interfaces |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| |
Volume |
99 |
Issue |
13 |
Pages |
132512-132512,3 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
We report bipolar resistive switching between the interfaces of manganite nanocolumns. La0.7Sr0.3MnO3 films were prepared on Al2O3 substrates, where the films grow in nanocolumns from the substrate to the surface. Conductive atomic force microscopy directly detects that the resistive switching is located at the boundaries of the grains. Furthermore, mesoscopic transport measurements reveal a tunnel magnetoresistance. In combination with the resistive switching, this leads to a total of four different resistive states. |
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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 |
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Language |
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Wos |
000295618000052 |
Publication Date |
2011-09-29 |
| |
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 |
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| |
ISSN |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.411 |
Times cited |
10 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
| |
Call Number |
UA @ lucian @ c:irua:91884 |
Serial |
2881 |
| Permanent link to this record |
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Author |
Scalise, E.; Houssa, M.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
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Title |
Inelastic electron tunneling spectroscopy of HfO2 gate stacks : a study based on first-principles modeling |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| |
Volume |
99 |
Issue |
13 |
Pages |
132101,1-132101,3 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
A first-principles modeling approach is used to investigate the vibrational properties of HfO2. The calculated phonon density of states is compared to experimental results obtained from inelastic electron tunneling spectroscopy (IETS) of various metal-oxide-semiconductor devices with HfO2 gate stacks. This comparison provides deep insights into the nature of the signatures of the complicated IETS spectra and provides valuable structural information about the gate stack, such as the possible presence of oxygen vacancies in jet-vapour deposited HfO2. Important structural differences between the interface of atomic-layer or molecular-beam deposited HfO2 and the Si substrate are also revealed. |
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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 |
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Language |
|
Wos |
000295618000036 |
Publication Date |
2011-09-26 |
| |
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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.411 |
Times cited |
1 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
| |
Call Number |
UA @ lucian @ c:irua:93611 |
Serial |
1606 |
| Permanent link to this record |
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|
Author |
Talgorn, E.; Gao, Y.; Aerts, M.; Kunneman, L.T.; Schins, J.M.; Savenije, T.J.; van Huis, M.A.; van der Zant, H.S.J.; Houtepen, A.J.; Siebbeles, L.D.A. |
| |
Title |
Unity quantum yield of photogenerated charges and band-like transport in quantum-dot solids |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
| |
Volume |
6 |
Issue |
11 |
Pages |
733-739 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Solid films of colloidal quantum dots show promise in the manufacture of photodetectors and solar cells. These devices require high yields of photogenerated charges and high carrier mobilities, which are difficult to achieve in quantum-dot films owing to a strong electronhole interaction and quantum confinement. Here, we show that the quantum yield of photogenerated charges in strongly coupled PbSe quantum-dot films is unity over a large temperature range. At high photoexcitation density, a transition takes place from hopping between localized states to band-like transport. These strongly coupled quantum-dot films have electrical properties that approach those of crystalline bulk semiconductors, while retaining the size tunability and cheap processing properties of colloidal quantum dots. |
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Address |
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| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000296737300012 |
Publication Date |
2011-09-25 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1748-3387;1748-3395; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
38.986 |
Times cited |
129 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 38.986; 2011 IF: 27.270 |
| |
Call Number |
UA @ lucian @ c:irua:93296 |
Serial |
3813 |
| Permanent link to this record |
| |
|
| |
|
Author |
Khaydarov, R.T.; Beisinbaeva, H.B.; Sabitov, M.M.; Kalal, M.; Berdiyorov, G.R. |
| |
Title |
Effect of light gas atom inclusions on the characteristics of laser-produced plasma ions |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Nuclear fusion |
Abbreviated Journal |
Nucl Fusion |
| |
Volume |
51 |
Issue |
10 |
Pages |
103041,1-103041,3 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Using the mass-spectrometric method we studied the effect of light gas inclusions on the formation process of multi-component laser-induced plasma ions. Masscharge characteristics, as well as energy and spatial distribution of the plasma ions are analysed. We found that both the energy and maximal charge of heavy component ions decrease due to the presence of gas atoms in the solid target surface layer. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Vienna |
Editor |
|
| |
Language |
|
Wos |
000296603800043 |
Publication Date |
2011-09-23 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0029-5515;1741-4326; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.307 |
Times cited |
1 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 3.307; 2011 IF: 4.090 |
| |
Call Number |
UA @ lucian @ c:irua:93761 |
Serial |
821 |
| Permanent link to this record |
| |
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| |
|
Author |
Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. |
| |
Title |
Hydrogen impurities and native defects in CdO |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| |
Volume |
110 |
Issue |
6 |
Pages |
063521,1-063521,7 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| |
Abstract |
We have used first-principles calculations based on density functional theory to study point defects in CdO within the local density approximation and beyond (LDA+U). Hydrogen interstitials and oxygen vacancies are found to act as shallow donors and can be interpreted as the cause of conductivity in CdO. Hydrogen can also occupy an oxygen vacancy in its substitutional form and also acts as a shallow donor. Similar to what was found for ZnO and MgO, hydrogen creates a multicenter bond with its six oxygen neighbors in CdO. The charge neutrality level for native defects and hydrogen impurities has been calculated. It is shown that in the case of native defects, it is not uniquely defined. Indeed, this level depends highly on the chemical potentials of the species and one can obtain different values for different end states in the experiment. Therefore, a comparison with experiment can only be made if the chemical potentials of the species in the experiment are well defined. However, for the hydrogen interstitial defect, since this level is independent of the chemical potential of hydrogen, one can obtain a unique value for the charge neutrality level. We find that the Fermi level stabilizes at 0.43 eV above the conduction band minimum in the case of the hydrogen interstitial defect, which is in good agreement with the experimentally reported value of 0.4 eV. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| |
Language |
|
Wos |
000295619300041 |
Publication Date |
2011-09-23 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.068 |
Times cited |
13 |
Open Access |
|
| |
Notes |
; The authors gratefully acknowledge financial support from the IWT-Vlaanderen through the ISIMADE project, the FWO-Vlaanderen through Project G.0191.08 and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC. ; |
Approved |
Most recent IF: 2.068; 2011 IF: 2.168 |
| |
Call Number |
UA @ lucian @ c:irua:93613 |
Serial |
1533 |
| Permanent link to this record |
| |
|
| |
|
Author |
Van Passel, S.; Meul, M. |
| |
Title |
Multilevel and multi-user sustainability assessment of farming systems |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Environmental Impact Assessment Review |
Abbreviated Journal |
Environ Impact Asses |
| |
Volume |
32 |
Issue |
1 |
Pages |
170-180 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology |
| |
Abstract |
Sustainability assessment is needed to build sustainable farming systems. A broad range of sustainability concepts, methodologies and applications already exists. They differ in level, focus, orientation, measurement, scale, presentation and intended end-users. In this paper we illustrate that a smart combination of existing methods with different levels of application can make sustainability assessment more profound, and that it can broaden the insights of different end-user groups. An overview of sustainability assessment tools on different levels and for different end-users shows the complementarities and the opportunities of using different methods. In a case-study, a combination of the sustainable value approach (SVA) and MOTIFS is used to perform a sustainability evaluation of farming systems in Flanders. SVA is used to evaluate sustainability at sector level, and is especially useful to support policy makers, while MOTIFS is used to support and guide farmers towards sustainability at farm level. The combined use of the two methods with complementary goals can widen the insights of both farmers and policy makers, without losing the particularities of the different approaches. To stimulate and support further research and applications, we propose guidelines for multilevel and multi-user sustainability assessments. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000297874000020 |
Publication Date |
2011-09-21 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0195-9255 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.094 |
Times cited |
49 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 3.094; 2012 IF: 1.851 |
| |
Call Number |
UA @ admin @ c:irua:94186 |
Serial |
6231 |
| Permanent link to this record |
| |
|
| |
|
Author |
Nelissen, K.; Partoens, B.; Peeters, F.M. |
| |
Title |
Influence of an ellipsoid on the angular order in a two-dimensional cluster |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
| |
Volume |
84 |
Issue |
3 |
Pages |
031405,1-031405,6 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The influence of an ellipsoid on the angular order of two-dimensional classical clusters is investigated through Brownian dynamics simulations. We found the following: (1) The presence of an ellipsoid does not influence the start of the angular melting, but reduces the rate at which the inner rings can rotate with respect to each other. (2) Even a small eccentricity of the ellipsoid leads to a stabilization of the angular order of the system. (3) Depending on the position of the ellipsoid in the cluster, a reentrant behavior in the angular order is observed before full radial melting of the cluster sets in. (4) The ellipsoid can lead to a two-step angular melting process: First, the rotation of the inner rings with respect to each other is hindered by the ellipsoid, but on further increasing the kinetic energy of the system, the ellipsoid just starts to behave as a spherical particle with different mobility. The effect of an ellipsoid on the molten system does not depend crucially on the interparticle interaction, but a softer parabolic confinement reduces the angular stabilization. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
| |
Language |
|
Wos |
000296495000007 |
Publication Date |
2011-09-20 |
| |
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 |
| |
Impact Factor |
2.366 |
Times cited |
|
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and CNPq. ; |
Approved |
Most recent IF: 2.366; 2011 IF: 2.255 |
| |
Call Number |
UA @ lucian @ c:irua:93612 |
Serial |
1615 |
| Permanent link to this record |
| |
|
| |
|
Author |
Dong, H.M.; Xu, W.; Peeters, F.M. |
| |
Title |
High-field transport properties of graphene |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| |
Volume |
110 |
Issue |
6 |
Pages |
063704,1-063704,6 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We present a theoretical investigation on the transport properties of graphene in the presence of high dc driving fields. Considering electron interactions with impurities and acoustic and optical phonons in graphene, we employ the momentum- and energy-balance equations derived from the Boltzmann equation to self-consistently evaluate the drift velocity and temperature of electrons in graphene in the linear and nonlinear response regimes. We find that the current-voltage relation exhibits distinctly nonlinear behavior, especially in the high electric field regime. Under the action of high-fields the large source-drain (sd) current density can be achieved and the current saturation in graphene is incomplete with increasing the sd voltage Vsd up to 3 V. Moreover, for high fields, Vsd>0.1 V, the heating of electrons in graphene occurs. It is shown that the sd current and electron temperature are sensitive to electron density and lattice temperature in the graphene device. This study is relevant to the application of graphene as high-field nano-electronic devices such as graphene field-effect transistors. |
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Address |
|
| |
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 |
000295619300059 |
Publication Date |
2011-09-19 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.068 |
Times cited |
17 |
Open Access |
|
| |
Notes |
; This work was supported by the National Natural Science Foundation of China (Grant No. 10974206) and the Department of Science and Technology of Yunnan Province. ; |
Approved |
Most recent IF: 2.068; 2011 IF: 2.168 |
| |
Call Number |
UA @ lucian @ c:irua:93614 |
Serial |
1433 |
| Permanent link to this record |
| |
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| |
|
Author |
Orlinskii, S.B.; Bogomolov, R.S.; Kiyamova, A.M.; Yavkin, B.V.; Mamin, G.M.; Turner, S.; Van Tendeloo, G.; Shiryaev, A.A.; Vlasov, I.I.; Shenderova, O. |
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Title |
Identification of substitutional nitrogen and surface paramagnetic centers in nanodiamond of dynamic synthesis by electron paramagnetic resonance |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Nanoscience and nanotechnology letters |
Abbreviated Journal |
Nanosci Nanotech Let |
| |
Volume |
3 |
Issue |
1 |
Pages |
63-67 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Production of nanodiamond particles containing substitutional nitrogen is important for a wide variety of advanced applications. In the current work nanodiamond particles synthesized from a mixture of graphite and hexogen were analyzed to determine the presence of substitutional nitrogen using pulsed electron paramagnetic resonance (EPR) spectroscopy. Nitrogen paramagnetic centers in the amount of 1.2 ppm have been identified. The spin relaxation characteristics for both nitrogen and surface defects are also reported. A new approach for efficient depletion of the strong non-nitrogen EPR signal in nanodiamond material by immersing nanodiamond particles into ice matrix is suggested. This approach allows an essential decrease of the spin relaxation time of the dominant non-nitrogen defects, while preserving the substitutional nitrogen spin relaxation time. |
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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 |
000293211200012 |
Publication Date |
2011-09-19 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1941-4900;1941-4919; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.889 |
Times cited |
14 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 1.889; 2011 IF: 0.528 |
| |
Call Number |
UA @ lucian @ c:irua:91943 |
Serial |
1548 |
| Permanent link to this record |
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| |
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Author |
Verbruggen, S.W.; Ribbens, S.; Tytgat, T.; Hauchecorne, B.; Smits, M.; Meynen, V.; Cool, P.; Martens, J.A.; Lenaerts, S. |
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Title |
The benefit of glass bead supports for efficient gas phase photocatalysis : case study of a commercial and a synthesised photocatalyst |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
| |
Volume |
174 |
Issue |
1 |
Pages |
318-325 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Sustainable Energy, Air and Water Technology (DuEL) |
| |
Abstract |
In the field of photocatalytic air purification, the immobilisation of catalyst particles on support surfaces without loss of photon efficiency is an important challenge. Therefore, an immobilisation method involving a one-step suspension coating of pre-synthesised photocatalysts on glass beads was applied. The various benefits are exemplified in the gas phase photodegradation of ethylene. Coating of glass beads is easy, fast, cheap and offers a more efficient alternative to bulk catalyst pellets. Furthermore, this coating procedure allows to use porous, pre-synthesised catalysts to their full potential, as the surface area and morphology of the initial powder is barely altered after coating, in strong contrast to pelletising. With this technique it became possible to study the gas phase photocatalytic activity of commercial titanium dioxide, trititanate nanotubes and mixed phase anatase/trititanate nanotubes in a packed bed reactor towards the degradation of ethylene without changing the catalyst properties. Coating of glass beads with the photocatalyst revealed the superior activity of the as-prepared nanotubes, compared to TiO2 Aerolyst® 7710 in gaseous phase. |
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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 |
000296950300041 |
Publication Date |
2011-09-17 |
| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1385-8947; 1873-3212 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.216 |
Times cited |
39 |
Open Access |
|
| |
Notes |
; The author wishes to acknowledge the Research Foundation of Flanders (FWO) for the financial support. Evonik is greatly thanked for supplying the TiO<INF>2</ INF> Aerolyst (R) 7710 pellets. ; |
Approved |
Most recent IF: 6.216; 2011 IF: 3.461 |
| |
Call Number |
UA @ admin @ c:irua:93364 |
Serial |
5929 |
| Permanent link to this record |
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| |
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Author |
Vodolazov, D.Y.; Peeters, F.M. |
| |
Title |
Origin of the hysteresis of the current voltage characteristics of superconducting microbridges near the critical temperature |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
84 |
Issue |
9 |
Pages |
094511 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The current voltage (IV) characteristics of short [with length L less than or similar to xi(T)] and long [L >> xi(T)] microbridges are theoretically investigated near the critical temperature of the superconductor. Calculations are made in the nonlocal (local) limit when the inelastic relaxation length due to electron-phonon interactions L(in) = (D tau(in))(1/2) is larger (smaller) than the temperature-dependent coherence length xi(T) (D is the diffusion coefficient, tau(in) is the inelastic relaxation time of the quasiparticle distribution function). We find that, in both limits, the origin of the hysteresis in the IV characteristics is mainly connected with the large time scale over which the magnitude of the order parameter varies in comparison with the time-scale variation of the superconducting phase difference across the microbridge in the resistive state. In the nonlocal limit, the time-averaged heating and cooling of quasiparticles are found in different areas of the microbridge, which are driven, respectively, by oscillations of the order parameter and the electric field. We show that, by introducing an additional term in the time-dependent Ginzburg-Landau equation, it is possible to take into account the cooling effect in the local limit too. |
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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 |
000294920900009 |
Publication Date |
2011-09-14 |
| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
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Edition |
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
|
| |
Notes |
; This work was supported by the Russian Foundation for Basic Research, Russian Agency of Education under the Federal Target Programme“Scientific and educational personnel of innovative Russia in 2009-2013,” the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
| |
Call Number |
UA @ lucian @ c:irua:105573 |
Serial |
2527 |
| Permanent link to this record |
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Author |
Kazakov, S.M.; Abakumov, A.M.; Perz-Mato, J.M.; Ovchinnikov, A.V.; Roslova, M.V.; Boltalin, A.I.; Morozov, I.V.; Antipov, E.V.; Van Tendeloo, G. |
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Title |
Uniform patterns of Fe-vacancy ordering in the Kx(Fe,Co)2-ySe2 superconductors |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| |
Volume |
23 |
Issue |
19 |
Pages |
4311-4316 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The Fe-vacancy ordering patterns in the superconducting KxFe2ySe2 and nonsuperconducting Kx(Fe,Co)2ySe2 samples have been investigated by electron diffraction and high angle annular dark field scanning transmission electron microscopy. The Fe-vacancy ordering occurs in the ab plane of the parent ThCr2Si2-type structure, demonstrating two types of patterns. Superstructure I retains the tetragonal symmetry and can be described with the aI = bI = as√5 (as is the unit cell parameter of the parent ThCr2Si2-type structure) supercell and I4/m space group. Superstructure II reduces the symmetry to orthorhombic with the aII = as√2, bII = 2as√2 supercell and the Ibam space group. This type of superstructure is observed for the first time in KxFe2ySe2. The Fe-vacancy ordering is inhomogeneous: the disordered areas interleave with the superstructures I and II in the same crystallite. The observed superstructures represent the compositionally dependent uniform ordering patterns of two species (the Fe atoms and vacancies) on a square lattice. More complex uniform ordered configurations, including compositional stripes, can be predicted for different chemical compositions of the KxFe2ySe2 (0 < y < 0.5) solid solutions. |
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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 |
000295487800005 |
Publication Date |
2011-09-13 |
| |
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 |
20 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
| |
Call Number |
UA @ lucian @ c:irua:92805 |
Serial |
3810 |
| Permanent link to this record |
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| |
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Author |
Tadić, M.; Čukarić, N.; Arsoski, V.; Peeters, F.M. |
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Title |
Excitonic Aharonov-Bohm effect : unstrained versus strained type-I semiconductor nanorings |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
84 |
Issue |
12 |
Pages |
125307-125307,13 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We study how mechanical strain affects the magnetic field dependence of the exciton states in type-I semiconductor nanorings. Strain spatially separates the electron and hole in (In,Ga)As/GaAs nanorings which is beneficial for the occurrence of the excitonic Aharonov-Bohm (AB) effect. In narrow strained (In,Ga)As/GaAs nanorings the AB oscillations in the exciton ground-state energy are due to anticrossings with the first excited state. No such AB oscillations are found in unstrained GaAs/(Al,Ga)As nanorings irrespective of the ring width. Our results are obtained within an exact numerical diagonalization scheme and are shown to be accurately described by a two-level model with off-diagonal coupling t. The later transfer integral expresses the Coulomb coupling between states of electron-hole pairs. We also found that the oscillator strength for exciton recombination in (In,Ga)As/GaAs nanorings exhibits AB oscillations, which are superimposed on a linear increase with magnetic field. Our results agree qualitatively with recent experiments on the excitonic Aharonov-Bohm effect in type-I (In,Ga)As/GaAs nanorings. |
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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 |
000294777400013 |
Publication Date |
2011-09-09 |
| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
|
| |
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 Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl), the EU NoE: SANDiE, and the Belgian Science Policy (IAP). The calculations were performed on the CalcUA and Seastar computer clusters of the University of Antwerp. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
| |
Call Number |
UA @ lucian @ c:irua:92326 |
Serial |
1122 |
| Permanent link to this record |
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|
| |
|
Author |
Fang, C.M.; van Huis, M.A.; Jansen, J.; Zandbergen, H.W. |
| |
Title |
Role of carbon and nitrogen in Fe2C and Fe2N from first-principles calculations |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
84 |
Issue |
9 |
Pages |
094102-094102,10 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Although Fe2C and Fe2N are technologically important materials, the exact nature of the chemical bonding of C and N atoms and the related impact on the electronic properties are at present unclear. Here, results of first-principles electronic structure calculations for Fe2X (X = C, N) phases are presented. The electronic structure calculations show that the roles of N and C in iron nitrides and carbides are comparable, and that the X-X interactions have significant impact on electronic properties. Accurate analysis of the spatially resolved differences in electron densities reveals a subtle distinction between the chemical bonding and charge transfer of N and C ions. |
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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 |
|
Wos |
000294772800003 |
Publication Date |
2011-09-09 |
| |
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 |
24 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
| |
Call Number |
UA @ lucian @ c:irua:92327 |
Serial |
2912 |
| Permanent link to this record |
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|
| |
|
Author |
Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. |
| |
Title |
Stability and structures of the CFCC-TmC phases : a first-principles study |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Computational materials science |
Abbreviated Journal |
Comp Mater Sci |
| |
Volume |
51 |
Issue |
1 |
Pages |
146-150 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The η-M6C, γ-M23C6, and π-M11C2 phases (M = Cr, Mn and Fe) have complex cubic lattices with lattice parameters of approximately 1.0 nm. They belong to the CFCC-TmC family (complex face-centered cubic transition metal carbides), display a rich variety of crystal structures, and play in important role in iron alloys and steels. Here we show that first-principles calculations predict high stability for the γ-M23C6 and η-M6C phases, and instability for the π-M11C2 phases, taking into account various compositional and structural possibilities. The calculations also show a wide variety in magnetic properties. The Cr-containing phases were found to be non-magnetic and the Fe-phases to be ferromagnetic, while the Mn-containing phases were found to be either ferrimagnetic or non-magnetic. Details of the local atomic structures, and the formation and stability of these precipitates in alloys are 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 |
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Editor |
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| |
Language |
|
Wos |
000296214300020 |
Publication Date |
2011-08-29 |
| |
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 |
0927-0256; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.292 |
Times cited |
18 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.292; 2012 IF: 1.878 |
| |
Call Number |
UA @ lucian @ c:irua:93277 |
Serial |
3119 |
| Permanent link to this record |
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Author |
Komendová, L.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M. |
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Title |
Different length scales for order parameters in two-gap superconductors : extended Ginzburg-Landau theory |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
84 |
Issue |
6 |
Pages |
064522-064522,5 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Using the Ginzburg-Landau theory extended to the next-to-leading order, we determine numerically the healing lengths of the two order parameters at the two-gap superconductor/normal metal interface. We demonstrate on several examples that those can be different even in the strict domain of applicability of the Ginzburg-Landau theory. This justifies the use of this theory to describe relevant physics of two-gap superconductors, distinguishing them from their single-gap counterparts. The calculational degree of complexity increases only slightly with respect to the conventional Ginzburg-Landau expansion, thus the extended Ginzburg-Landau model remains numerically far less demanding compared to the full microscopic approaches. |
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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 |
000294226000013 |
Publication Date |
2011-08-25 |
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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 |
56 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
| |
Call Number |
UA @ lucian @ c:irua:92414 |
Serial |
695 |
| Permanent link to this record |
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Author |
Vernimmen, J.; Meynen, V.; Herregods, S.J.F.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Cool, P. |
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Title |
New insights in the formation of combined zeolitic/mesoporous materials by using a one-pot templating synthesis |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
European journal of inorganic chemistry |
Abbreviated Journal |
Eur J Inorg Chem |
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Volume |
|
Issue |
27 |
Pages |
4234-4240 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
| |
Abstract |
Zeolitic growth is often absent or occurs in separate phases when synthetic strategies based on the combination of zeolite templates and mesopore templating agents are applied. In this work, zeolitic growth and mesopore formation have been investigated at different temperatures by applying a one-pot templating approach, based on a TS-1 zeolite synthesis whereby part of the microtemplate (tetrapropylammonium hydroxide, TPAOH) is replaced by a mesotemplate (hexadecyltrimethylammonium bromide, CTMABr). Moreover, the synthesis duration and the molar ratio of the microtemplate/mesotemplate have also been studied. The different syntheses clearly show the inherent competitive mechanism between zeolitic growth and mesopore formation. These insights have led to the conclusion that by following a one-pot templating strategy with standard, nonexotic commercial templates, i.e. CTMABr and TPAOH, it is not possible to develop a true hierarchical mesoporous zeolite, meaning a mesoporous siliceous material with highly crystalline zeolitic walls. The resultant materials are instead combined zeolitic/mesoporous composite structures with, however, highly tuneable and controllable porosity 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 |
Weinheim |
Editor |
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Language |
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Wos |
000296143500014 |
Publication Date |
2011-08-17 |
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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 |
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Series Issue |
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Edition |
|
| |
ISSN |
1434-1948; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.444 |
Times cited |
7 |
Open Access |
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.444; 2011 IF: 3.049 |
| |
Call Number |
UA @ lucian @ c:irua:91574 |
Serial |
2315 |
| Permanent link to this record |
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Author |
Klimczuk, T.; Wang, C.H.; Lawrence, J.M.; Xu, Q.; Durakiewicz, T.; Ronning, F.; Llobet, A.; Trouw, F.; Kurita, N.; Tokiwa, Y.; Lee, H.o.; Booth, C.H.; Gardner, J.S.; Bauer, E.D.; Joyce, J.J.; Zandbergen, H.W.; Movshovich, R.; Cava, R.J.; Thompson, J.D.; |
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Title |
Crystal fields, disorder, and antiferromagnetic short-range order in Yb0.24Sn0.76Ru |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
84 |
Issue |
7 |
Pages |
075152-075152,8 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
We report extensive measurements on a new compound (Yb0.24Sn0.76)Ru that crystallizes in the cubic CsCl structure. Valence-band photoemission (PES) and L3 x-ray absorption show no divalent component in the 4f configuration of Yb. Inelastic neutron scattering (INS) indicates that the eight-fold degenerate J-multiplet of Yb3+ is split by the crystalline electric field (CEF) into a Γ7-doublet ground state and a Γ8 quartet at an excitation energy 20 meV. The magnetic susceptibility can be fit very well by this CEF scheme under the assumption that a Γ6-excited state resides at 32 meV; however, the Γ8/Γ6 transition expected at 12 meV was not observed in the INS. The resistivity follows a Bloch-Grüneisen law shunted by a parallel resistor, as is typical of systems subject to phonon scattering with no apparent magnetic scattering. All of these properties can be understood as representing simple local moment behavior of the trivalent Yb ion. At 1 K there is a peak in specific heat that is too broad to represent a magnetic-phase transition, consistent with absence of magnetic reflections in neutron diffraction. On the other hand this peak also is too narrow to represent the Kondo effect in the Γ7-doublet ground state. On the basis of the field dependence of the specific heat, we argue that antiferromagnetic (AF) short-range order (SRO) (possibly coexisting with Kondo physics) occurs at low temperatures. The long-range magnetic order is suppressed because the Yb site occupancy is below the percolation threshold for this disordered compound. |
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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 |
000293830800003 |
Publication Date |
2011-08-15 |
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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 |
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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 |
8 |
Open Access |
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
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Call Number |
UA @ lucian @ c:irua:92427 |
Serial |
555 |
| Permanent link to this record |
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Author |
Shestakov, M.V.; Tikhomirov, V.K.; Kirilenko, D.; Kuznetsov, A.S.; Chibotaru, L.F.; Baranov, A.N.; Van Tendeloo, G.; Moshchalkov, V.V. |
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Title |
Quantum cutting in Li (770 nm) and Yb (1000 nm) co-dopant emission bands by energy transfer from the ZnO nano-crystalline host |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Optics express |
Abbreviated Journal |
Opt Express |
| |
Volume |
19 |
Issue |
17 |
Pages |
15955-15964 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Li-Yb co-doped nano-crystalline ZnO has been synthesized by a method of thermal growth from the salt mixtures. X-ray diffraction, transmission electron microscopy, atomic absorption spectroscopy and optical spectroscopy confirm the doping and indicate that the dopants may form Li-Li and Yb3+-Li based nanoclusters. When pumped into the conduction and exciton absorption bands of ZnO between 250 to 425 nm, broad emission bands of about 100 nm half-height-width are excited around 770 and 1000 nm, due to Li and Yb dopants, respectively. These emission bands are activated by energy transfer from the ZnO host mostly by quantum cutting processes, which generate pairs of quanta in Li (770 nm) and Yb (1000 nm) emission bands, respectively, out of one quantum absorbed by the ZnO host. These quantum cutting phenomena have great potential for application in the down-conversion layers coupled to the Si solar cells. |
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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 |
000293894900033 |
Publication Date |
2011-08-04 |
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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 |
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Series Issue |
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Edition |
|
| |
ISSN |
1094-4087; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.307 |
Times cited |
19 |
Open Access |
|
| |
Notes |
FWO; Methusalem |
Approved |
Most recent IF: 3.307; 2011 IF: 3.587 |
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Call Number |
UA @ lucian @ c:irua:92428 |
Serial |
2776 |
| Permanent link to this record |
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Author |
Özen, M.; Mertens, M.; Luyten, J.; Snijkers, F.; d' Hondt, H.; Cool, P. |
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Title |
Hydrothermal synthesis of carbonate-free submicron-sized barium titanate from an amorphous precursor : synthesis and characterization |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Ceramics international |
Abbreviated Journal |
Ceram Int |
| |
Volume |
38 |
Issue |
1 |
Pages |
619-625 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
| |
Abstract |
In this paper, the amorphous barium titanate precursor was prepared by the peroxo-hydroxide method and post-treated by various drying procedures, such as: room temperature drying, room temperature vacuum drying and vacuum drying at 50 degrees C. The objective in the latter two treatments was to increase the Ti-O-Ba bonds of the precursor. The post-treated precursors were compared with the untreated (i.e., 'wet') precursor. Also, a barium titanate precursor was prepared by an alkoxide route. Afterwards, the precursors were hydrothermally treated at 200 degrees C in a 10 M NaOH solution. Vacuum drying of the precursor seemingly promoted the formation of Ti-O-Ti bonds in the hydrothermal end-product. The low Ba:Ti ratio (0.66) of the alkoxide-route prepared precursor lead to a multi-phase hydrothermal product with BaTiO(3) as the main phase. In contrast, phase pure BaTiO(3), i.e. without BaCO(3) contamination, was obtained for the precursor which was dried at room temperature. Cube-shaped and highly crystalline BaTiO(3) particles were observed by electron microscopy for the hydrothermally treated peroxo-hydroxide-route prepared precursor. (C) 2011 Elsevier Ltd and Techna Group S.r.l. 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 |
Barking |
Editor |
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Language |
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Wos |
000298766900083 |
Publication Date |
2011-08-02 |
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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 |
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Series Issue |
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Edition |
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ISSN |
0272-8842; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.986 |
Times cited |
14 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 2.986; 2012 IF: 1.789 |
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Call Number |
UA @ lucian @ c:irua:96263 |
Serial |
1541 |
| Permanent link to this record |
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Author |
Delabie, A.; Sioncke, S.; Rip, J.; van Elshocht, S.; Caymax, M.; Pourtois, G.; Pierloot, K. |
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Title |
Mechanisms for the trimethylaluminum reaction in aluminum oxide atomic layer deposition on sulfur passivated germanium |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
115 |
Issue |
35 |
Pages |
17523-17532 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Germanium combined with high-κ dielectrics is investigated for the next generations of CMOS devices. Therefore, we study reaction mechanisms for Al2O3 atomic layer deposition on sulfur passivated Ge using calculations based on density functional theory and total reflection X-ray fluorescence (TXRF). TXRF indicates 6 S/nm2 and 4 Al/nm2 after the first TMA/H2O reaction cycle, and growth inhibition from the second reaction cycle on. Calculations are performed on molecular clusters representing −GeSH surface sites. The calculations confirm that the TMA reaction does not affect the S content. On fully SH-terminated Ge, TMA favorably reacts with up to three −GeSH sites, resulting in a near tetrahedral Al coordination. Electron deficient structures with a GeS site shared between two Al atoms are proposed. The impact of the cluster size on the structures and reaction energetics is systematically investigated. |
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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, D.C. |
Editor |
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Language |
|
Wos |
000294386000037 |
Publication Date |
2011-08-01 |
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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 |
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Series Issue |
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Edition |
|
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ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.536 |
Times cited |
9 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 4.536; 2011 IF: 4.805 |
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Call Number |
UA @ lucian @ c:irua:91714 |
Serial |
1980 |
| Permanent link to this record |
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Author |
Xu, B.; Milošević, M.V.; Lin, S.-H.; Peeters, F.M.; Jankó, B. |
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Title |
Formation of multiple-flux-quantum vortices in mesoscopic superconductors from simulations of calorimetric, magnetic, and transport properties |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| |
Volume |
107 |
Issue |
5 |
Pages |
057002,1-057002,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Because of strong flux confinement in mesoscopic superconductors, a giant vortex may appear in the ground state of the system in an applied magnetic field. This multiquanta vortex can then split into individual vortices (and vice versa) as a function of, e.g., applied current, magnetic field, or temperature. Here we show that such transitions can be identified by calorimetry, as the formation or splitting of a giant vortex results in a clear jump in measured heat capacity versus external drive. We attribute this phenomenon to an abrupt change in the density of states of the quasiparticle excitations in the vortex core(s), and further link it to a sharp change of the magnetic susceptibility at the transitionproving that the formation of a giant vortex can also be detected by magnetometry. |
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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 |
New York, N.Y. |
Editor |
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| |
Language |
|
Wos |
000293333100006 |
Publication Date |
2011-07-29 |
| |
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 |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
8.462 |
Times cited |
26 |
Open Access |
|
| |
Notes |
; We thank O. Bourgeois, T. Yokoyama, M. Eschrig, and M. Ichioka for discussions. This work was supported by FWO-Vlaanderen, the Belgian Science Policy (IAP), the bilateral project Flanders-USA, NSF NIRT, ECS-0609249, and Institute of Theoretical Sciences, Notre Dame. ; |
Approved |
Most recent IF: 8.462; 2011 IF: 7.370 |
| |
Call Number |
UA @ lucian @ c:irua:91237 |
Serial |
1263 |
| Permanent link to this record |
