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Records |
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Author |
Ranjbari, E.; Hadjmohammadi, M.R.; Kiekens, F.; De Wael, K. |
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Title |
Mixed hemi/ad-micelle sodium dodecyl sulfate-coated magnetic iron oxide nanoparticles for the efficient removal and trace determination of rhodamine-B and rhodamine-6G |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| |
Volume |
87 |
Issue  |
15 |
Pages |
7894-7901 |
| |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| |
Abstract |
Mixed hemi/ad-micelle sodium dodecyl sulfate (SDS)-coated magnetic iron oxide nanoparticles (MHAMS-MIONPs) were used as an efficient adsorbent for both removal and preconcentration of two important carcinogenic xanthine dyes named rhodamine-B (RB) and rhodamine-6G (RG). To gain insight in the configuration of SDS molecules on the surface of MIONPs, zeta potential measurements were performed in different [SDS]/[MIONP] ratios. Zeta potential data indicated that mixed hemi/ad-micelle MHAM was formed in [SDS]/[MIONP] ratios over the range of 1.1 to 7.3. Parameters affecting the adsorption of dyes were optimized as removal efficiency by one variable at-a-time and response surface methodology; the obtained removal efficiencies were ∼100%. Adsorption kinetic and equilibrium studies, under the optimum condition (pH = 2; amount of MIONPs = 87.15 mg; [SDS]/[MIONP] ratio = 2.9), showed that adsorption of both dyes are based on the pseudo-second-order and the Langmuir isotherm models, respectively. The maximum adsorption capacities for RB and RG were 385 and 323 mg g1, respectively. MHAMS-MIONPs were also applied for extraction of RB and RG. Under optimum conditions (pH = 2; amount of damped MHAMS-MIONPs = 90 mg; eluent solvent volume = 2.6 mL of 3% acetic acid in acetonitrile), extraction recoveries for 0.5 mg L1 of RB and RG were 98% and 99%, with preconcentration factors of 327 and 330, respectively. Limit of detection obtained for rhodamine dyes were <0.7 ng mL1. Finally, MHAMS-MIONPs were successfully applied for both removal and trace determination of RB and RG in environmental and wastewater samples. |
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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 |
000359277900056 |
Publication Date |
2015-07-08 |
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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 |
|
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ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.32 |
Times cited |
36 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 6.32; 2015 IF: 5.636 |
| |
Call Number |
UA @ admin @ c:irua:126583 |
Serial |
5730 |
| Permanent link to this record |
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Author |
Van Eyndhoven, G.; Kurttepeli, M.; van Oers, C.J.; Cool, P.; Bals, S.; Batenburg, K.J.; Sijbers, J. |
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Title |
Pore REconstruction and Segmentation (PORES) method for improved porosity quantification of nanoporous materials |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| |
Volume |
148 |
Issue |
148 |
Pages |
10-19 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab; Laboratory of adsorption and catalysis (LADCA) |
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Abstract |
Electron tomography is currently a versatile tool to investigate the connection between the structure and properties of nanomaterials. However, a quantitative interpretation of electron tomography results is still far from straightforward. Especially accurate quantification of pore-space is hampered by artifacts introduced in all steps of the processing chain, i.e., acquisition, reconstruction, segmentation and quantification. Furthermore, most common approaches require subjective manual user input. In this paper, the PORES algorithm POre REconstruction and Segmentation is introduced; it is a tailor-made, integral approach, for the reconstruction, segmentation, and quantification of porous nanomaterials. The PORES processing chain starts by calculating a reconstruction with a nanoporous-specific reconstruction algorithm: the Simultaneous Update of Pore Pixels by iterative REconstruction and Simple Segmentation algorithm (SUPPRESS). It classifies the interior region to the pores during reconstruction, while reconstructing the remaining region by reducing the error with respect to the acquired electron microscopy data. The SUPPRESS reconstruction can be directly plugged into the remaining processing chain of the PORES algorithm, resulting in accurate individual pore quantification and full sample pore statistics. The proposed approach was extensively validated on both simulated and experimental data, indicating its ability to generate accurate statistics of nanoporous materials. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000345973000002 |
Publication Date |
2014-08-23 |
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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 |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
7 |
Open Access |
OpenAccess |
| |
Notes |
Colouratom; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); |
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
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Call Number |
c:irua:119083 |
Serial |
2672 |
| Permanent link to this record |
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Author |
Gorle, C.; Garcia Sánchez, C.; Iaccarino, G. |
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Title |
Quantifying inflow and RANS turbulence model form uncertainties for wind engineering flows |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of wind engineering and industrial aerodynamics
T2 – 6th International Symposium on Computational Wind Engineering (CWE), JUN 08-12, 2014, Hamburg, GERMANY |
Abbreviated Journal |
J Wind Eng Ind Aerod |
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Volume |
144 |
Issue |
144 |
Pages |
202-212 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Reynolds-averaged Navier-Stokes (RANS) simulations are often used in the wind engineering practice for the analysis of turbulent bluff body flows. An approach that allows identifying the uncertainty related to the use of reduced-order turbulence models in RANS simulations would significantly increase the confidence in the use of simulation results as a basis for design decisions. In the present study we apply a strategy that enables quantifying these uncertainties by introducing perturbations in the Reynolds stress tensor to simulations of the flow in downtown Oklahoma City. The method is combined with a framework to quantify uncertainties in the inflow wind direction and intensity, and the final result of the UQ approach is compared to field measurement data for the velocity at 13 locations in the downtown area. (C) 2015 Elsevier Ltd. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Elsevier science bv |
Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000360874900023 |
Publication Date |
2015-08-18 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
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Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0167-6105 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.049 |
Times cited |
22 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.049; 2015 IF: 1.414 |
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Call Number |
UA @ lucian @ c:irua:127843 |
Serial |
4230 |
| Permanent link to this record |
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Author |
Euan-Diaz, E.; Herrera-Velarde, S.; Misko, V.R.; Peeters, F.M.; Castaneda-Priego, R. |
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Title |
Structural transitions and long-time self-diffusion of interacting colloids confined by a parabolic potential |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
142 |
Issue |
142 |
Pages |
024902 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We report on the ordering and dynamics of interacting colloidal particles confined by a parabolic potential. By means of Brownian dynamics simulations, we find that by varying the magnitude of the trap stiffness, it is possible to control the dimension of the system and, thus, explore both the structural transitions and the long-time self-diffusion coefficient as a function of the degree of confinement. We particularly study the structural ordering in the directions perpendicular and parallel to the confinement. Further analysis of the local distribution of the first-neighbors layer allows us to identify the different structural phases induced by the parabolic potential. These results are summarized in a structural state diagram that describes the way in which the colloidal suspension undergoes a structural re-ordering while increasing the confinement. To fully understand the particle dynamics, we take into account hydrodynamic interactions between colloids; the parabolic potential constricts the available space for the colloids, but it does not act on the solvent. Our findings show a non-linear behavior of the long-time self-diffusion coefficient that is associated to the structural transitions induced by the external field. (C) 2015 AIP Publishing LLC. |
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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 |
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Wos |
000348129700053 |
Publication Date |
2015-01-10 |
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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 |
0021-9606;1089-7690; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.965 |
Times cited |
7 |
Open Access |
|
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Notes |
; This work was partially supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), PIFI 3.4 – PROMEP, and CONACyT (Grant Nos. 61418/2007, 102339/2008, Ph.D. scholarship 230171/2010). R.C.-P. also acknowledges financial support provided by the Marcos Moshinsky fellowship 2013-2014. The authors also thank to the General Coordination of Information and Communications Technologies (CGSTIC) at Cinvestav for providing HPC resources on the Hybrid Cluster Super-computer Xiuhcoatl, which have contributed partially to the research results reported in this paper. ; |
Approved |
Most recent IF: 2.965; 2015 IF: 2.952 |
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Call Number |
c:irua:123832 |
Serial |
3267 |
| Permanent link to this record |
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Author |
Chen, Y.Z.; Trier, F.; Wijnands, T.; Green, R.J.; Gauquelin, N.; Egoavil, R.; Christensen, D.V.; Koster, G.; Huijben, M.; Bovet, N.; Macke, S.; He, F.; Sutarto, R.; Andersen, N.H.; Sulpizio, J.A.; Honig, M.; Prawiroatmodjo, G.E.D.K.; Jespersen, T.S.; Linderoth, S.; Ilani, S.; Verbeeck, J.; Van Tendeloo, G.; Rijnders, G.; Sawatzky, G.A.; Pryds, N. |
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Title |
Extreme mobility enhancement of two-dimensional electron gases at oxide interfaces by charge-transfer-induced modulation doping |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
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Volume |
14 |
Issue |
14 |
Pages |
801-806 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Two-dimensional electron gases (2DEGs) formed at the interface of insulating complex oxides promise the development of all-oxide electronic devices. These 2DEGs involve many-body interactions that give rise to a variety of physical phenomena such as superconductivity, magnetism, tunable metalinsulator transitions and phase separation. Increasing the mobility of the 2DEG, however, remains a major challenge. Here, we show that the electron mobility is enhanced by more than two orders of magnitude by inserting a single-unit-cell insulating layer of polar La1−xSrxMnO3 (x = 0, 1/8, and 1/3) at the interface between disordered LaAlO3 and crystalline SrTiO3 produced at room temperature. Resonant X-ray spectroscopy and transmission electron microscopy show that the manganite layer undergoes unambiguous electronic reconstruction, leading to modulation doping of such atomically engineered complex oxide heterointerfaces. At low temperatures, the modulation-doped 2DEG exhibits Shubnikovde Haas oscillations and fingerprints of the quantum Hall effect, demonstrating unprecedented high mobility and low electron density. |
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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 |
000358530100022 |
Publication Date |
2015-06-01 |
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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 |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
39.737 |
Times cited |
170 |
Open Access |
|
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Notes |
246102 IFOX; 246791 COUNTATOMS; 278510 VORTEX; Hercules; 312483 ESTEEM2; FWO G004413N; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 39.737; 2015 IF: 36.503 |
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Call Number |
c:irua:127184 c:irua:127184UA @ admin @ c:irua:127184 |
Serial |
1163 |
| Permanent link to this record |
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Author |
Sathiya, M.; Abakumov, A.M.; Foix, D.; Rousse, G.; Ramesha, K.; Saubanère, M.; Doublet, M. .; Vezin, H.; Laisa, C.P.; Prakash, A.S.; Gonbeau, D.; Van Tendeloo, G.; Tarascon, J.M. |
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Title |
Origin of voltage decay in high-capacity layered oxide electrodes |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
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Volume |
14 |
Issue |
14 |
Pages |
230-238 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Although Li-rich layered oxides (Li1+xNiyCozMn1−x−y−zO2 > 250 mAh g−1) are attractive electrode materials providing energy densities more than 15% higher than todays commercial Li-ion cells, they suffer from voltage decay on cycling. To elucidate the origin of this phenomenon, we employ chemical substitution in structurally related Li2RuO3 compounds. Li-rich layered Li2Ru1−yTiyO3 phases with capacities of ~240 mAh g−1 exhibit the characteristic voltage decay on cycling. A combination of transmission electron microscopy and X-ray photoelectron spectroscopy studies reveals that the migration of cations between metal layers and Li layers is an intrinsic feature of the chargedischarge process that increases the trapping of metal ions in interstitial tetrahedral sites. A correlation between these trapped ions and the voltage decay is established by expanding the study to both Li2Ru1−ySnyO3 and Li2RuO3; the slowest decay occurs for the cations with the largest ionic radii. This effect is robust, and the finding provides insights into new chemistry to be explored for developing high-capacity layered electrodes that evade voltage decay. |
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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 |
000348600200024 |
Publication Date |
2014-12-01 |
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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 |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
39.737 |
Times cited |
395 |
Open Access |
|
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Notes |
246791 Countatoms; 312483 Esteem2; esteem2_ta |
Approved |
Most recent IF: 39.737; 2015 IF: 36.503 |
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Call Number |
c:irua:132555 c:irua:132555 |
Serial |
2528 |
| Permanent link to this record |
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Author |
Bia, P.; Caratelli, D.; Mescia, L.; Gielis, J. |
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Title |
Analysis and synthesis of supershaped dielectric lens antennas |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
IET microwaves, antennas and propagation |
Abbreviated Journal |
|
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Volume |
9 |
Issue |
14 |
Pages |
1497-1504 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Mass communications; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
A novel class of supershaped dielectric lens antennas, whose geometry is described by the three-dimensional (3D) Gielis formula, is introduced and analysed. To this end, a hybrid modelling approach based on geometrical and physical optics is adopted in order to efficiently analyse the multiple wave reflections occurring within the lens and to evaluate the relevant impact on the radiation properties of the antenna under analysis. The developed modelling procedure has been validated by comparison with numerical results already reported in the literature and, afterwards, applied to the electromagnetic characterisation of Gielis dielectric lens antennas with shaped radiation pattern. Furthermore, a dedicated optimisation algorithm based on quantum particle swarm optimisation has been developed for the synthesis of 3D supershaped lens antennas with single feed, as well as with beamforming capabilities. |
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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 |
000364491200002 |
Publication Date |
2015-08-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
1751-8725 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
|
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:128659 |
Serial |
7441 |
| Permanent link to this record |
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Author |
McCalla, E.; Sougrati, M.T.; Rousse, G.; Berg, E.J.; Abakumov, A.; Recham, N.; Ramesha, K.; Sathiya, M.; Dominko, R.; Van Tendeloo, G.; Novák, P.; Tarascon, J.M.; |
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Title |
Understanding the roles of anionic redox and oxygen release during electrochemical cycling of lithium-rich layered Li4FeSbO6 |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
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Volume |
137 |
Issue |
137 |
Pages |
4804-4814 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Li-rich oxides continue to be of immense interest as potential next generation Li-ion battery positive electrodes, and yet the role of oxygen during cycling is still poorly understood. Here, the complex electrochemical behavior of Li4FeSbO6 materials is studied thoroughly with a variety of methods. Herein, we show that oxygen release occurs at a distinct voltage plateau from the peroxo/superoxo formation making this material ideal for revealing new aspects of oxygen redox processes in Li-rich oxides. Moreover, we directly demonstrate the limited reversibility of the oxygenated species (O-2(n-); n = 1, 2, 3) for the first time. We also find that during charge to 4.2 V iron is oxidized from +3 to an unusual +4 state with the concomitant formation of oxygenated species. Upon further charge to 5.0 V, an oxygen release process associated with the reduction of iron +4 to +3 is present, indicative of the reductive coupling mechanism between oxygen and metals previously reported. Thus, in full state of charge, lithium removal is fully compensated by oxygen only, as the iron and antimony are both very close to their pristine states. Besides, this charging step results in complex phase transformations that are ultimately destructive to the crystallinity of the material. Such findings again demonstrate the vital importance of fully understanding the behavior of oxygen in such systems. The consequences of these new aspects of the electrochemical behavior of lithium-rich oxides are discussed in detail. |
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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 |
000353177100036 |
Publication Date |
2015-03-26 |
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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 |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.858 |
Times cited |
86 |
Open Access |
|
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Notes |
|
Approved |
Most recent IF: 13.858; 2015 IF: 12.113 |
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Call Number |
c:irua:126019 |
Serial |
3805 |
| Permanent link to this record |
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Author |
Semkina, A.; Abakumov, M.; Grinenko, N.; Abakumov, A.; Skorikov, A.; Mironova, E.; Davydova, G.; Majouga, A.G.; Nukolova, N.; Kabanov, A.; Chekhonin, V.; |
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Title |
Core-shell-corona doxorubicin-loaded superparamagnetic Fe3O4 nanoparticles for cancer theranostics |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Colloids and surfaces: B : biointerfaces |
Abbreviated Journal |
Colloid Surface B |
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Volume |
136 |
Issue |
136 |
Pages |
1073-1080 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Superparamagnetic iron oxide magnetic nanoparticles (MNPs) are successfully used as contrast agents in magnetic-resonance imaging. They can be easily functionalized for drug delivery functions, demonstrating great potential for both imaging and therapeutic applications. Here we developed new pH-responsive theranostic core-shell-corona nanoparticles consisting of superparamagentic Fe3O4 core that displays high T2 relaxivity, bovine serum albumin (BSA) shell that binds anticancer drug, doxorubicin (Dox) and poly(ethylene glycol) (PEG) corona that increases stability and biocompatibility. The nanoparticles were produced by adsorption of the BSA shell onto the Fe3O4 core followed by crosslinking of the protein layer and subsequent grafting of the PEG corona using monoamino-terminated PEG via carbodiimide chemistry. The hydrodynamic diameter, zeta-potential, composition and T2 relaxivity of the resulting nanoparticles were characterized using transmission electron microscopy, dynamic light scattering, thermogravimetric analysis and T2-relaxometry. Nanoparticles were shown to absorb Dox molecules, possibly through a combination of electrostatic and hydrophobic interactions. The loading capacity (LC) of the nanoparticles was 8 wt.%. The Dox loaded nanoparticles release the drug at a higher rate at pH 5.5 compared to pH 7.4 and display similar cytotoxicity against C6 and HEK293 cells as the free Dox. (C) 2015 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
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Language |
|
Wos |
000367408100131 |
Publication Date |
2015-11-10 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0927-7765 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.887 |
Times cited |
37 |
Open Access |
|
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Notes |
|
Approved |
Most recent IF: 3.887; 2015 IF: 4.152 |
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Call Number |
UA @ lucian @ c:irua:131075 |
Serial |
4157 |
| Permanent link to this record |
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Author |
Ercolani, G.; Gorle, C.; Garcia Sánchez, C.; Corbari, C.; Mancini, M. |
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Title |
RAMS and WRF sensitivity to grid spacing in large-eddy simulations of the dry convective boundary layer |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Computers and fluids |
Abbreviated Journal |
Comput Fluids |
| |
Volume |
123 |
Issue |
123 |
Pages |
54-71 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Large-eddy simulations (LESS) are frequently used to model the planetary boundary layer, and the choice of the grid cell size, numerical schemes and sub grid model can significantly influence the simulation results. In the present paper the impact of grid spacing on LES of an idealized atmospheric convective boundary layer (CBL), for which the statistics and flow structures are well understood, is assessed for two mesoscale models: the Regional Atmospheric Modeling System (RAMS) and the Weather Research and Forecasting model (WRF). Nine simulations are performed on a fixed computational domain (6 x 6 x 2 km), combining three different horizontal (120, 60, 30 m) and vertical (20, 10, 5 m) spacings. The impact of the cell size on the CBL is investigated by comparing turbulence statistics and velocity spectra. The results demonstrate that both WRF and RAMS can perform LES of the CBL under consideration without requiring extremely high computational loads, but they also indicate the importance of adopting a computational grid that is adequate for the numerical schemes and subgrid models used. In both RAMS and WRF a horizontal cell size of 30 m is required to obtain a suitable turbulence reproduction throughout the CBL height. Considering the vertical grid spacing, WRF produced similar results for all the three tested values, while in RAMS it should be ensured that the aspect ratio of the cells does not exceed a value of 3. The two models were found to behave differently in function of the grid resolution, and they have different shortcomings in their prediction of CBL turbulence. WRF exhibits enhanced damping at the smallest scales, while RAMS is prone to the appearance of spurious fluctuations in the flow when the grid aspect ratio is too high. (C) 2015 Elsevier Ltd. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000365367500006 |
Publication Date |
2015-10-08 |
| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0045-7930 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.313 |
Times cited |
3 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.313; 2015 IF: 1.619 |
| |
Call Number |
UA @ lucian @ c:irua:130200 |
Serial |
4236 |
| Permanent link to this record |
| |
|
| |
|
Author |
Papageorgiou, D.G.; Filippousi, M.; Pavlidou, E.; Chrissafis, K.; Van Tendeloo, G.; Bikiaris, D. |
| |
Title |
Effect of clay modification on structureproperty relationships and thermal degradation kinetics of \beta-polypropylene/clay composite materials |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of thermal analysis and calorimetry |
Abbreviated Journal |
J Therm Anal Calorim |
| |
Volume |
122 |
Issue |
122 |
Pages |
393-406 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The influence of neat and organically modified montmorillonite on the structureproperty relationships of a β-nucleated polypropylene matrix has been thoroughly investigated. High-angle annular dark field scanning transmission electron microscopy revealed that the organic modification of clay facilitated the dispersion of the clay, while X-ray diffractograms showed the α-nucleating effect of the clays on the β-nucleated matrix. The results from tensile tests showed that the organic modification of MMT affected profoundly only the tensile strength at yield and at break. The effect of the organic modification of the clay on the thermal stability of the composites was finally evaluated by thermogravimetric analysis, where the samples filled with oMMT decomposed faster than the ones filled with neat MMT, due to the decomposition of the organic salts that were initially used for the modification of MMT. A kinetics study of the thermal degradation of the composites was also performed, in order to export additional conclusions on the activation energy of the samples. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
S.l. |
Editor |
|
| |
Language |
|
Wos |
000361431200042 |
Publication Date |
2015-04-29 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1388-6150;1588-2926; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.953 |
Times cited |
7 |
Open Access |
|
| |
Notes |
262348 Esmi |
Approved |
Most recent IF: 1.953; 2015 IF: 2.042 |
| |
Call Number |
c:irua:127492 |
Serial |
805 |
| Permanent link to this record |
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| |
|
Author |
Ramakers, M.; Michielsen, I.; Aerts, R.; Meynen, V.; Bogaerts, A. |
| |
Title |
Effect of argon or helium on the CO2 conversion in a dielectric barrier discharge |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Plasma processes and polymers |
Abbreviated Journal |
Plasma Process Polym |
| |
Volume |
12 |
Issue |
12 |
Pages |
755-763 |
| |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
This paper demonstrates that the CO2 conversion in a dielectric barrier discharge rises drastically upon addition of Ar or He, and the effect is more pronounced for Ar than for He. The effective CO2 conversion, on the other hand, drops upon addition of Ar or He, which is logical due to the lower CO2 content in the gas mixture, and the same is true for the energy efficiency, because a considerable fraction of the energy is then consumed into ionization/excitation of Ar or He atoms. The higher absolute CO2 conversion upon addition of Ar or He can be explained by studying in detail the Lissajous plots and the current profiles. The breakdown voltage is lower in the CO2/Ar and CO2/He mixtures, and the discharge gap is more filled with plasma, which enhances the possibility for CO2 conversion. The rates of electron impact excitationdissociation of CO2, estimated from the electron densities and mean electron energies, are indeed higher in the CO2/Ar and (to a lower extent) in the CO2/He mixtures, compared to the pure CO2 plasma. Moreover, charge transfer between Ar+ or Ar2+ ions and CO2, followed by electron-ion dissociative recombination of the CO2+ ions, might also contribute to, or even be dominant for the CO2 dissociation. All these effects can explain the higher CO2 conversion, especially upon addition of Ar, but also upon addition of He. |
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Address |
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| |
Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| |
Language |
|
Wos |
000359672400007 |
Publication Date |
2015-02-12 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1612-8850; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.846 |
Times cited |
63 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.846; 2015 IF: 2.453 |
| |
Call Number |
c:irua:126822 |
Serial |
799 |
| Permanent link to this record |
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| |
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Author |
Yusupov, M.; Neyts, E.C.; Verlackt, C.C.; Khalilov, U.; van Duin, A.C.T.; Bogaerts, A. |
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Title |
Inactivation of the endotoxic biomolecule lipid A by oxygen plasma species : a reactive molecular dynamics study |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Plasma processes and polymers |
Abbreviated Journal |
Plasma Process Polym |
| |
Volume |
12 |
Issue |
12 |
Pages |
162-171 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
Reactive molecular dynamics simulations are performed to study the interaction of reactive oxygen species, such as OH, HO2 and H2O2, with the endotoxic biomolecule lipid A of the gram-negative bacterium Escherichia coli. It is found that the aforementioned plasma species can destroy the lipid A, which consequently results in reducing its toxic activity. All bond dissociation events are initiated by hydrogen-abstraction reactions. However, the mechanisms behind these dissociations are dependent on the impinging plasma species, i.e. a clear difference is observed in the mechanisms upon impact of HO2 radicals and H2O2 molecules on one hand and OH radicals on the other hand. Our simulation results are in good agreement with experimental observations. |
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Address |
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| |
Language |
|
Wos |
000350275400005 |
Publication Date |
2014-09-17 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1612-8850; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.846 |
Times cited |
18 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.846; 2015 IF: 2.453 |
| |
Call Number |
c:irua:123540 |
Serial |
1589 |
| Permanent link to this record |
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Author |
Vanmeert, F.; van der Snickt, G.; Janssens, K. |
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Title |
Plumbonacrite identified by X-ray powder diffraction tomography as a missing link during degradation of red lead in a Van Gogh painting |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
| |
Volume |
54 |
Issue |
12 |
Pages |
3607-3610 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Red lead, a semiconductor pigment used by artists since antiquity, is known to undergo several discoloration phenomena. These transformations are either described as darkening of the pigment caused by the formation of either plattnerite (β-PbO2) or galena (PbS) or as whitening by which red lead is converted into anglesite (PbSO4) or (hydro)cerussite (2 PbCO3⋅Pb(OH)2; PbCO3). X-ray powder diffraction tomography, a powerful analytical method that allows visualization of the internal distribution of different crystalline compounds in complex samples, was used to investigate a microscopic paint sample from a Van Gogh painting. A very rare lead mineral, plumbonacrite (3 PbCO3⋅ Pb(OH)2⋅PbO), was revealed to be present. This is the first reported occurrence of this compound in a painting dating from before the mid 20th century. It constitutes the missing link between on the one hand the photoinduced reduction of red lead and on the other hand (hydro)cerussite, and thus sheds new light on the whitening of red lead. |
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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 |
000351178300008 |
Publication Date |
2015-02-20 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1433-7851; 0570-0833 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
11.994 |
Times cited |
24 |
Open Access |
|
| |
Notes |
; The authors acknowledge L. Van der Loeff and M. Leeuwestein (Kroller-Muller Museum) for providing the paint sample. We thank Dr. J. Jaroszewicz (WUT) for performing the CT measurements. This research was carried out at the light source PETRA III at DESY, a member of the Helmholtz Association (HGF). We thank Dr. G. Falkenberg and the members of his team for their assistance in using beam line P06. We acknowledge financial support from the University of Antwerp GOA projects “XANES meets EELS” and “SOLARPaint”, as well as from BELSPO (Brussels) Project S2-ART and FWO (Brussels) project “ESRF-Dubble”. ; |
Approved |
Most recent IF: 11.994; 2015 IF: 11.261 |
| |
Call Number |
UA @ admin @ c:irua:124620 |
Serial |
5774 |
| Permanent link to this record |
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Author |
Caretti, I.; Keulemans, M.; Verbruggen, S.W.; Lenaerts, S.; Van Doorslaer, S. |
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Title |
Light-induced processes in plasmonic Gold/TiO2 photocatalysts studied by electron paramagnetic resonance |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Topics in catalysis |
Abbreviated Journal |
Top Catal |
| |
Volume |
58 |
Issue |
12 |
Pages |
776-782 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
X-band and W-band continuous-wave (CW) electron paramagnetic resonance (EPR) was used to study in situ light-induced (LI) mechanisms in commercial P90 titania (90 % anatase/10 % rutile) compared to plasmon-enhanced Au-P90 photocatalyst. These materials were excited using UV and 532 nm visible light to generate different excitation states and distinguish pure charge separation from plasmon-assisted resonance processes. Up to nine different photoinduced species of trapped electrons and holes were identified. LI CW EPR of P90 is presented for the first time, showing a UV excitation response similar to the well-known mixed-phase P25 titania. It is shown that incorporation of Au nanoparticles in Au-P90 and formation of a Schottky junction affects the charge separation state of the catalyst under UV light. Moreover, Au impregnation activated P90 through plasmon hot electron injection under visible light excitation (plasmonic sensitization effect). In general, EPR proved to be crucial to determine the different photoexciation paths and reactions that regulate plasmonic photocatalysis. |
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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 |
000360011200008 |
Publication Date |
2015-08-03 |
| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1022-5528 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.486 |
Times cited |
22 |
Open Access |
|
| |
Notes |
; IC and SVD acknowledge the Research Foundation-Flanders (FWO) for financial support (Grant G.0687.13). SV thanks FWO for financial support through a postdoctoral fellowship and MK acknowledges the agency for Innovation by Science and Technology in Flanders (IWT) for financial support (Ph.D. Grant). ; |
Approved |
Most recent IF: 2.486; 2015 IF: 2.365 |
| |
Call Number |
UA @ admin @ c:irua:127413 |
Serial |
5968 |
| Permanent link to this record |
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Author |
Tirez, K.; Vanhoof, C.; Bronders, J.; Seuntjens, P.; Bleux, N.; Berghmans, P.; De Brucker, N.; Vanhaecke, F. |
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Title |
Do ICP-MS based methods fulfill the EU monitoring requirements for the determination of elements in our environment? |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Environmental science : processes & impacts |
Abbreviated Journal |
|
| |
Volume |
17 |
Issue |
12 |
Pages |
2034-2050 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Undoubtedly, the most important advance in the environmental regulatory monitoring of elements of the last decade is the widespread introduction of ICP-mass spectrometry (ICP-MS) due to standards developed by the European Committee for Standardization. The versatility of ICP-MS units as a tool for the determination of major, minor and trace elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sn, Ti, V and Zn) in surface water, groundwater, river sediment, topsoil, subsoil, fine particulates and atmospheric deposition is illustrated in this paper. Ranges of background concentrations for major, minor and trace elements obtained from a regional case study (Flanders, Belgium) are summarized for all of these environmental compartments and discussed in the context of a harmonized implementation of European regulatory monitoring requirements. The results were derived from monitoring programs in support of EU environmental quality directives and were based on a selection of (non-polluted) background locations. Because of the availability of ICP-MS instruments nowadays, it can be argued that the main hindrance for meeting the European environmental monitoring requirements is no longer the technical feasibility of analysis at these concentration levels, but rather (i) potential contamination during sampling and analysis, (ii) too limited implementation of quality control programs, validating the routinely applied methods (including sampling and low level verification) and (iii) lack of harmonization in reporting of the chemical environmental status between the individual member states. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
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Language |
|
Wos |
000365915600005 |
Publication Date |
2015-10-06 |
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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 |
2050-7887; 2050-7895 |
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:130316 |
Serial |
7821 |
| Permanent link to this record |
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Author |
Huygh, S.; Neyts, E.C. |
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Title |
Adsorption of C and CHx radicals on anatase (001) and the influence of oxygen vacancies |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
4908-4921 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
The adsorption of C and CHx radicals on anatase (001) was studied using DFT within the generalized gradient approximation using the Perde-Burke-Ernzerhof (PBE) functional. We have studied the influence of oxygen vacancies in and at the surface on the adsorption properties of the radicals. For the oxygen vacancies in anatase (001), the most stable vacancy is located at the surface. For this vacancy, the maximal adsorption strength of C and CH decreases compared to the adsorption on the stoichiometric surface, but it increases for CH2 and CH3. If an oxygen vacancy is present in the first subsurface layer, the maximal adsorption strength increases for C, CH, CH2, and CH3. When the vacancy is present in the next subsurface layer, we find that only the CH3 adsorption is enhanced, while the maximal adsorption energies for the other radical species decrease. Not only does the precise location of the oxygen vacancy determine the maximal adsorption interaction, it also influences the adsorption strengths of the radicals at different surface configurations. This determines the probability of finding a certain adsorption configuration at the surface, which in turn influences the possible surface reactions. We find that C preferentially adsorbs far away from the oxygen vacancy, while CH2 and CH3 adsorb preferentially at the oxygen vacancy site. A fraction of CH partially adsorbs at the oxygen vacancy, and another fraction adsorbs further away from the vacancy. |
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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 |
000350840700052 |
Publication Date |
2015-02-18 |
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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 |
13 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
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Call Number |
c:irua:124909 |
Serial |
63 |
| Permanent link to this record |
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Author |
Quan Manh, P.; Pourtois, G.; Swerts, J.; Pierloot, K.; Delabie, A. |
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Title |
Atomic layer deposition of Ruthenium on Ruthenium surfaces : a theoretical study |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
6592-6603 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Atomic, layer deposition,(ALD of ruthenium using two ruthenium precursors, i.e., Ru(C5H5)(2) (RuCp2) and Ru(C5H5)(C4H4N) (RuCpPy), is studied using density functional theory. By investigating the reaction mechanisms On bare ruthenium surfaces, i.e., (001), (101), and (100), and H-terminated surfaces, an atomistic insight in the Ru ALD is provided. The calculated results show that on the Ru surfaces both RuCp2 and RuCpPy an undergo dehydrogenation and ligand dissociation reactions. RuCpPy is more reactive than RuCp2. By forming a, strong, bond between N of Py and Ru of the surface, RuCpPy can easily chemisorb on the surfaces. The reactions of RuCp2,On the Surfaces are less favorable the adsorption is not strong enough This could be a,factor contributing to the higher growth-per-cycle of Ru using RuCpPy, as observed experimentally. By Studying, the adsorption on H-terminated Ru surfaces, We showed that H Can prevent the adsorption of the precursors, thus inhibiting the growth of Ru. Our calculations indicate that the H content on the surface can have an impact on the growth-per-cycle. Finally, our simulations also demonstrate large impacts of the surface structure on the reaction mechanisms. Of the three surfaces, the (100) surface, which is the less stable and has a zigzag surface structure, is also the most reactive one. |
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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 |
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Language |
|
Wos |
000351970800015 |
Publication Date |
2015-03-04 |
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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 |
|
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 |
10 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
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Call Number |
c:irua:125544 |
Serial |
171 |
| Permanent link to this record |
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Author |
Kato, T.; Neyts, E.C.; Abiko, Y.; Akama, T.; Hatakeyama, R.; Kaneko, T. |
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Title |
Kinetics of energy selective Cs encapsulation in single-walled carbon nanotubes for damage-free and position-selective doping |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
11903-11908 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
A method has been developed for damage-free cesium (Cs) encapsulation within single-walled carbon nanotubes (SWNTs) with fine position selectivity. Precise energy tuning of Cs-ion irradiation revealed that there is a clear energy window (2060 eV) for the efficient encapsulation of Cs through the hexagonal network of SWNT sidewalls without causing significant damage. This minimum energy threshold of Cs-ion encapsulation (∼20 eV) matches well with the value obtained by ab initio simulation (∼22 eV). Furthermore, position-selective Cs encapsulation was carried out, resulting in the successful formation of pn-junction SWNT thin films with excellent environmental stability. |
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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 |
000355495600072 |
Publication Date |
2015-05-06 |
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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 |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.536 |
Times cited |
3 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
| |
Call Number |
c:irua:125928 |
Serial |
1760 |
| Permanent link to this record |
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Author |
De Bie, C.; van Dijk, J.; Bogaerts, A. |
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Title |
The Dominant Pathways for the Conversion of Methane into Oxygenates and Syngas in an Atmospheric Pressure Dielectric Barrier Discharge |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
22331-22350 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
A one-dimensional fluid model for a dielectric barrier discharge in CH4/O2 and CH4/CO2 gas mixtures is developed. The model describes the gas-phase chemistry for partial oxidation and for dry reforming of methane. The spatially averaged densities of the various plasma species are presented as a function of time and initial gas mixing ratio. Besides, the conversion of the inlet gases and the selectivities of the reaction products are calculated. Syngas, higher hydrocarbons, and higher oxygenates are typically found to be important reaction products. Furthermore, the main underlying reaction pathways for the formation of syngas, methanol, formaldehyde, and other higher oxygenates are determined. |
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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 |
000362385700010 |
Publication Date |
2015-09-10 |
| |
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 |
46 |
Open Access |
|
| |
Notes |
This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the Universiteit Antwerpen. The authors also acknowledge financial support from the IAP/7 (Interuniversity Attraction Pole) program “PSI-Physical Chemistry of Plasma- Surface Interactions” by the Belgian Federal Office for Science Policy (BELSPO) and from the Fund for Scientific Research Flanders (FWO). |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
| |
Call Number |
c:irua:128774 |
Serial |
3960 |
| Permanent link to this record |
| |
|
| |
|
Author |
Nicholls, D.; Li, R.R.; Ware, B.; Pansegrau, C.; Çakir, D.; Hoffmann, M.R.; Oncel, N. |
| |
Title |
Scanning tunneling microscopy and density functional theory study on zinc(II)-phthalocyanine tetrasulfonic acid on bilayer epitaxial graphene on silicon carbide(0001) |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
9845-9850 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
Zinc(II)-phthalocyanine tetrasulfonic acid (Zn-PcS) molecules physisorbed on bilayer epitaxial graphene on silicon carbide (SiC(0001)) were studied by using scanning tunneling microscopy/spectroscopy (STM/STS) and density functional theory (DFT). Two different methods were used to deposit Zn-PcS molecules and regardless of the method being used, the surface coverage stayed very low indicating the weakness of surface-molecule interaction. STS measurements revealed that derivative of tunneling current with respect to voltage (dI/dV) measured on Zn-PcS molecules did not exhibit the characteristic dip observed on dI/dV curves of pristine bilayer epitaxial graphene. DFT calculations show that the energy of the lowest unoccupied molecular orbital (LUMO) of the Zn-PcS molecule is below the Dirac point of graphene which enhances local density of states (LDOS). We attribute the disappearance of the dip in the dI/dV curves measured on the Zn-PcS/bilayer system to the LUMO of Zn-PcS. Charge density calculations along Zn-PcS/graphene interface reveal that there is a small charge transfer from graphene to the molecule. Calculated adsorption energy (3.13 eV) of the molecule is notably low and is consistent with the observed low surface coverage at room temperature. |
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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 |
000354339000020 |
Publication Date |
2015-04-15 |
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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 |
3 |
Open Access |
|
| |
Notes |
; We gratefully acknowledge the NSF (Grant Nos.: DMR-1306101, EPS-814442, and EPS-1354366) for financial support. ; |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
| |
Call Number |
c:irua:126370 |
Serial |
2947 |
| Permanent link to this record |
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|
| |
|
Author |
Esfahani; Leenaerts, O.; Sahin, H.; Partoens, B.; Peeters, F.M. |
| |
Title |
Structural transitions in monolayer MOS2 by lithium adsorption |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
10602-10609 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
Based on first-principles calculations, we study the structural stability of the H and T phases of monolayer MoS2 upon Li doping. Our calculations demonstrate that it is possible to stabilize a distorted T phase of MoS2 over the H phase through adsorption of Li atoms on the MoS2 surface. Through molecular dynamics and phonon calculations, we show that the T phase of MoS2 is dynamically unstable and undergoes considerable distortions. The type of distortion depends on the concentration of adsorbed Li atoms and changes from zigzag-like to diamond-like when increasing the Li doping. There exists a substantial energy barrier to transform the stable H phase to the distorted T phases, which is considerably reduced by increasing the concentration of Li atoms. We show that it is necessary that the Li atoms adsorb on both sides of the MoS2 monolayer to reduce the barrier sufficiently. Two processes are examined that allow for such two-sided adsorption, namely, penetration through the MoS2 layer and diffusion over the MoS2 surface. We show that while there is only a small barrier of 0.24 eV for surface diffusion, the amount of energy needed to pass through a pure MoS2 layer is of the order of similar or equal to 2 eV. However, when the MoS2 layer is covered with Li atoms the amount of energy that Li atoms should gain to penetrate the layer is drastically reduced and penetration becomes feasible. |
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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 |
000354912200051 |
Publication Date |
2015-04-07 |
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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 |
96 |
Open Access |
|
| |
Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl) and the Methusalem program of the Flemish government. H. S is supported by an FWO Pegasus-Long Marie Curie fellowship. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government department EWI. ; |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
| |
Call Number |
c:irua:126409 |
Serial |
3270 |
| Permanent link to this record |
| |
|
| |
|
Author |
Heijkers, S.; Snoeckx, R.; Kozák, T.; Silva, T.; Godfroid, T.; Britun, N.; Snyders, R.; Bogaerts, A. |
| |
Title |
CO2 conversion in a microwave plasma reactor in the presence of N2 : elucidating the role of vibrational levels |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
12815-12828 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
A chemical kinetics model is developed for a CO2/N2 microwave plasma, focusing especially on the vibrational levels of both CO2 and N2. The model is used to calculate the CO2 and N2 conversion as well as the energy efficiency of CO2 conversion for different power densities and for N2 fractions in the CO2/N2 gas mixture ranging from 0 to 90%. The calculation results are compared with measurements, and agreements within 23% and 33% are generally found for the CO2 conversion and N2 conversion, respectively. To explain the observed trends, the destruction and formation processes of both CO2 and N2 are analyzed, as well as the vibrational distribution functions of both CO2 and N2. The results indicate that N2 contributes in populating the lower asymmetric levels of CO2, leading to a higher absolute CO2 conversion upon increasing N2 fraction. However, the effective CO2 conversion drops because there is less CO2 initially present in the gas mixture; thus, the energy efficiency also drops with rising N2 fraction. |
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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 |
000356317500005 |
Publication Date |
2015-05-13 |
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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 |
56 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
| |
Call Number |
c:irua:126325 |
Serial |
3523 |
| Permanent link to this record |
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| |
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Author |
Kang, J.; Sahin, H.; Peeters, F.M. |
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Title |
Tuning carrier confinement in the MoS2/WS2 lateral heterostructure |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
9580-9586 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
To determine and control the spatial confinement of charge carriers is of importance for nanoscale optoelectronic device applications. Using first-principles calculations, we investigate the tunability of band alignment and Charge localization in lateral and combined lateral vertical heterostructures of MoS2 and WS2. First, we Show that a type-II to type-I band alignment transition takes place when tensile strain is applied on the WS2 region. This band alignment transition is a result of the different response of the band edge states with strain and is caused by their different wave function characters. Then we show that the presence of the grain boundary introduces localized in-gap states. The boundary at the armchair interface significantly modifies the charge distribution of the valence band maximum (VBM) state, whereas in a heterostructure with tilt grain domains both conducation band maximum (CBM) and VBM are found to be localized around the grain boundary. We also found that the thickness of the constituents in a lateral heterostructure also determines how the electrons and holes are confined. Creating combined lateral vertical heterostructures of MOS2/WS2 provides another way cif tuning the charge confinement. These results provide possible ways to tune the carrier confinement in MoS2/WS2 heterostructures, which are interesting for its practical: applications in the future. |
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Address |
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000353930700066 |
Publication Date |
2015-04-07 |
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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 |
73 |
Open Access |
|
| |
Notes |
; This work was supported by the Methusalem program of the Flemish government. H.S. is supported by a FWO Pegasus Marie Curie-long Fellowship and J.K. by a FWO Pegasus Marie Curie-short Fellowship. ; |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
| |
Call Number |
c:irua:126381 |
Serial |
3747 |
| Permanent link to this record |
| |
|
| |
|
Author |
Iyikanat, F.; Sahin, H.; Senger, R.T.; Peeters, F.M. |
| |
Title |
Vacancy formation and oxidation characteristics of single layer TiS3 |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
10709-10715 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
The structural, electronic, and magnetic properties of pristine, defective, and oxidized monolayer TiS3 are investigated using first-principles calculations in the framework of density functional theory. We found that a single layer of TiS3 is a direct band gap semiconductor, and the bonding nature of the crystal is fundamentally different from other transition metal chalcogenides. The negatively charged surfaces of single layer TiS3 makes this crystal a promising material for lubrication applications. The formation energies of possible vacancies, i.e. S, Ti, TiS, and double S, are investigated via total energy optimization calculations. We found that the formation of a single S vacancy was the most likely one among the considered vacancy types. While a single S vacancy results in a nonmagnetic, semiconducting character with an enhanced band gap, other vacancy types induce metallic behavior with spin polarization of 0.3-0.8 mu(B). The reactivity of pristine and defective TiS3 crystals against oxidation was investigated using conjugate gradient calculations where we considered the interaction with atomic O, O-2, and O-3. While O-2 has the lowest binding energy with 0.05-0.07 eV, O-3 forms strong bonds stable even at moderate temperatures. The strong interaction (3.9-4.0 eV) between atomic O and TiS3 results in dissociative adsorption of some O-containing molecules. In addition, the presence of S-vacancies enhances the reactivity of the surface with atomic O, whereas it had a negative effect on the reactivity with O-2 and O-3 molecules. |
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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 |
000354912200063 |
Publication Date |
2015-04-28 |
| |
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 |
51 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. RI., H.S., and R.T.S. acknowledge the support from TUBITAK through project 114F397. ; |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
| |
Call Number |
c:irua:126410 |
Serial |
3829 |
| Permanent link to this record |
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| |
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Author |
Alyörük, M.M.; Aierken, Y.; Çakır, D.; Peeters, F.M.; Sevik, C. |
| |
Title |
Promising Piezoelectric Performance of Single Layer Transition-Metal Dichalcogenides and Dioxides |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
119 |
Issue |
119 |
Pages |
23231-23237 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
Piezoelectricity is a unique material property that allows one to convert mechanical energy into electrical one or vice versa. Transition metal dichalcogenides (TMDC) and transition metal dioxides (TMDO) are expected to have great potential for piezoelectric device applications due to their noncentrosymmetric and two-dimensional crystal structure. A detailed theoretical investigation of the piezoelectric stress (e 11 ) and piezoelectric strain (d 11 ) coefficients of single layer TMDCs and TMDOs with chemical formula MX 2 (where M= Cr, Mo, W, Ti, Zr, Hf, Sn and X = O, S, Se, Te) is presented by using first-principles calculations based on density func- tional theory. We predict that not only the Mo- and W-based members of this family but also the other materials with M= Cr, Ti, Zr and Sn exhibit highly promising piezoelectric properties. CrTe 2 has the largest e 11 and d 11 coefficients among the group VI elements (i.e., Cr, Mo, and W). In addition, the relaxed-ion e 11 and d 11 coefficients of SnS 2 are almost the same as those of CrTe 2 . Furthermore, TiO 2 and ZrO 2 pose comparable or even larger e 11 coefficients as compared to Mo- and W-based TMDCs and TMDOs. Our calculations reveal that TMDC and TMDO structures are strong candidates for future atomically thin piezoelectric applications such as transducers, sensors, and energy harvesting devices due to their piezoelectric coefficients that are comparable (even larger) to currently used bulk piezoelectric materials. |
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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 |
000362702100054 |
Publication Date |
2015-09-14 |
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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 |
1932-7447 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.536 |
Times cited |
134 |
Open Access |
|
| |
Notes |
M.M.A and C.S. acknowledges the support from Scientific and Technological Research Council of Turkey (TUBITAK- 113F333). C.S. acknowledges support from Anadolu University (BAP-1407F335, -1505F200), and Turkish Academy of Sciences (TUBA-GEBIP). Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
| |
Call Number |
c:irua:129418 |
Serial |
4035 |
| Permanent link to this record |
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|
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Author |
Berdiyorov, G.; Harrabi, K.; Mehmood, U.; Peeters, F.M.; Tabet, N.; Zhang, J.; Hussein, I.A.; McLachlan, M.A. |
| |
Title |
Derivatization and diffusive motion of molecular fullerenes : ab initio and atomistic simulations |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| |
Volume |
118 |
Issue |
118 |
Pages |
025101 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Using first principles density functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of derivatization on the electronic and transport properties of C-60 fullerene. As a typical example, we consider [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM), which forms one of the most efficient organic photovoltaic materials in combination with electron donating polymers. Extra peaks are observed in the density of states (DOS) due to the formation of new electronic states localized at/near the attached molecule. Despite such peculiar behavior in the DOS of an isolated molecule, derivatization does not have a pronounced effect on the electronic transport properties of the fullerene molecular junctions. Both C-60 and PCBM show the same response to finite voltage biasing with new features in the transmission spectrum due to voltage induced delocalization of some electronic states. We also study the diffusive motion of molecular fullerenes in ethanol solvent and inside poly(3-hexylthiophene) lamella using reactive molecular dynamics simulations. We found that the mobility of the fullerene reduces considerably due to derivatization; the diffusion coefficient of C-60 is an order of magnitude larger than the one for PCBM. (c) 2015 AIP Publishing LLC. |
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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 |
000357961000036 |
Publication Date |
2015-07-10 |
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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 |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.068 |
Times cited |
2 |
Open Access |
|
| |
Notes |
; K.H., U.M. and I.A.H. would like to thank the National Science, Technology and Innovation Program of KACST for funding this research under Project No. 12-ENE2379-04. They also acknowledge support from KFUPM and Research Institute. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
| |
Call Number |
c:irua:127098 |
Serial |
652 |
| Permanent link to this record |
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| |
|
Author |
Zhao, S.-X.; Gao, F.; Wang, Y.-P.; Wang, Y.-N.; Bogaerts, A. |
| |
Title |
Effects of feedstock availability on the negative ion behavior in a C4F8 inductively coupled plasma |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| |
Volume |
118 |
Issue |
118 |
Pages |
033301 |
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
In this paper, the negative ion behavior in a C4F8 inductively coupled plasma (ICP) is investigated using a hybrid model. The model predicts a non-monotonic variation of the total negative ion density with power at low pressure (1030 mTorr), and this trend agrees well with experiments that were carried out in many fluorocarbon (fc) ICP sources, like C2F6, CHF3, and C4F8. This behavior is explained by the availability of feedstock C4F8 gas as a source of the negative ions, as well as by the presence of low energy electrons due to vibrational excitation at low power. The maximum of the negative ion density shifts to low power values upon decreasing pressure, because of the more pronounced depletion of C4F8 molecules, and at high pressure (∼50 mTorr), the anion density continuously increases with power, which is similar to fc CCP sources. Furthermore, the negative ion composition is identified in this paper. Our work demonstrates that for a clear understanding of the negative ion behavior in radio frequency C4F8 plasma sources, one needs to take into account many factors, like the attachment characteristics, the anion composition, the spatial profiles, and the reactor configuration. Finally, a detailed comparison of our simulation results with experiments is conducted. |
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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 |
000358429200004 |
Publication Date |
2015-07-20 |
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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 |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.068 |
Times cited |
1 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
| |
Call Number |
c:irua:126735 |
Serial |
861 |
| Permanent link to this record |
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Author |
Milovanović, S.P.; Moldovan, D.; Peeters, F.M. |
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Title |
Veselago lensing in graphene with a p-n junction: Classical versus quantum effects |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| |
Volume |
118 |
Issue |
118 |
Pages |
154308 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The feasibility of Veselago lensing in graphene with a p-n junction is investigated numerically for realistic injection leads. Two different set-ups with two narrow leads are considered with absorbing or reflecting side edges. This allows us to separately determine the influence of scattering on electron focusing for the edges and the p-n interface. Both semiclassical and tight-binding simulations show a distinctive peak in the transmission probability that is attributed to the Veselago lensing effect. We investigate the robustness of this peak on the width of the injector, the position of the p-n interface, and different gate potential profiles. Furthermore, the influence of scattering by both short- and long-range impurities is considered. |
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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 |
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Wos |
000363535800022 |
Publication Date |
2015-10-20 |
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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 |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.068 |
Times cited |
19 |
Open Access |
|
| |
Notes |
This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
| |
Call Number |
c:irua:129452 |
Serial |
3969 |
| Permanent link to this record |
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Author |
Schoeters, B.; Leenaerts, O.; Pourtois, G.; Partoens, B. |
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Title |
Ab-initio study of the segregation and electronic properties of neutral and charged B and P dopants in Si and Si/SiO2 nanowires |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| |
Volume |
118 |
Issue |
118 |
Pages |
104306 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
We perform first-principles calculations to investigate the preferred positions of B and P dopants, both neutral and in their preferred charge state, in Si and Si/SiO2 core-shell nanowires (NWs). In order to understand the observed trends in the formation energy, we isolate the different effects that determine these formation energies. By making the distinction between the unrelaxed and the relaxed formation energy, we separate the impact of the relaxation from that of the chemical environment. The unrelaxed formation energies are determined by three effects: (i) the effect of strain caused by size mismatch between the dopant and the host atoms, (ii) the local position of the band edges, and (iii) a screening effect. In the case of the SiNW (Si/SiO2 NW), these effects result in an increase of the formation energy away from the center (interface). The effect of relaxation depends on the relative size mismatch between the dopant and host atoms. A large size mismatch causes substantial relaxation that reduces the formation energy considerably, with the relaxation being more pronounced towards the edge of the wires. These effects explain the surface segregation of the B dopants in a SiNW, since the atomic relaxation induces a continuous drop of the formation energy towards the edge. However, for the P dopants, the formation energy starts to rise when moving from the center but drops to a minimum just next to the surface, indicating a different type of behavior. It also explains that the preferential location for B dopants in Si/SiO2 core-shell NWs is inside the oxide shell just next to the interface, whereas the P dopants prefer the positions next to the interface inside the Si core, which is in agreement with recent experiments. These preferred locations have an important impact on the electronic properties of these core-shell NWs. Our simulations indicate the possibility of hole gas formation when B segregates into the oxide shell. |
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Wos |
000361636900031 |
Publication Date |
2015-09-09 |
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0021-8979 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
3 |
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Notes |
This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish government and the Universiteit Antwerpen. |
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Most recent IF: 2.068; 2015 IF: 2.183 |
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Call Number |
c:irua:128729 |
Serial |
4056 |
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