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Author |
Kaminsky, F.V.; Ryabchikov, I.D.; McCammon, C.A.; Longo, M.; Abakumov, A.M.; Turner, S.; Heidari, H. |
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Title |
Oxidation potential in the Earth's lower mantle as recorded by ferropericlase inclusions in diamond |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Earth and planetary science letters |
Abbreviated Journal |
Earth Planet Sc Lett |
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Volume |
417 |
Issue |
417 |
Pages |
49-56 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Ferropericlase (fPer) inclusions from kimberlitic lower-mantle diamonds recovered in the Juina area, Mato Grosso State, Brazil were analyzed with transmission electron microscopy, electron energy-loss spectroscopy and the flank method. The presence of exsolved non-stoichiometric Fe3+-enriched clusters, varying in size from 1-2 nm to 10-15 nm and comprising similar to 3.64 vol.% of fPer was established. The oxidation conditions necessary for fPer formation within the uppermost lower mantle (P = 25 GPa, T = 1960 K) vary over a wide range: Delta log f(o2) (IW) from 1.58 to 7.76 (Delta = 6.2), reaching the fayalite-magnetite-quartz (FMQ) oxygen buffer position. This agrees with the identification of carbonates and free silica among inclusions within lower-mantle Juina diamonds. On the other hand, at the base of the lower mantle Delta log f(o2) values may lie at and below the iron-wustite (IW) oxygen buffer. Hence, the variations of Delta log f(o2) values within the entire sequence of the lower mantle may reach ten logarithmic units, varying from the IW buffer to the FMQ buffer values. The similarity between lower- and upper-mantle redox conditions supports whole mantle convection, as already suggested on the basis of nitrogen and carbon isotopic compositions in lower- and upper-mantle diamonds. The mechanisms responsible for redox differentiation in the lower mantle may include subduction of oxidized crustal material, mechanical separation of metallic phase(s) and silicate-oxide mineral assemblages enriched in ferric iron, as well as transfer of fused silicate-oxide material presumably also enriched in ferric iron through the mantle. (C) 2015 Elsevier B.V. All rights reserved. |
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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 |
000351799400006 |
Publication Date |
2015-03-05 |
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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 |
0012-821X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.409 |
Times cited |
23 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.409; 2015 IF: 4.734 |
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Call Number |
c:irua:125451 |
Serial |
2539 |
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Permanent link to this record |
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Author |
Van der Paal, J.; Verlackt, C.C.; Yusupov, M.; Neyts, E.C.; Bogaerts, A. |
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Title |
Structural modification of the skin barrier by OH radicals : a reactive molecular dynamics study for plasma medicine |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
48 |
Issue |
48 |
Pages |
155202 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
While plasma treatment of skin diseases and wound healing has been proven highly effective, the underlying mechanisms, and more generally the effect of plasma radicals on skin tissue, are not yet completely understood. In this paper, we perform ReaxFF-based reactive molecular dynamics simulations to investigate the interaction of plasma generated OH radicals with a model system composed of free fatty acids, ceramides, and cholesterol molecules. This model system is an approximation of the upper layer of the skin (stratum corneum). All interaction mechanisms observed in our simulations are initiated by H-abstraction from one of the ceramides. This reaction, in turn, often starts a cascade of other reactions, which eventually lead to the formation of aldehydes, the dissociation of ceramides or the elimination of formaldehyde, and thus eventually to the degradation of the skin barrier function. |
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Thesis |
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Place of Publication |
London |
Editor |
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Wos |
000351856600007 |
Publication Date |
2015-03-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
20 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2015 IF: 2.721 |
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Call Number |
c:irua:124230 |
Serial |
3242 |
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Permanent link to this record |
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Author |
Tinck, S.; Tillocher, T.; Dussart, R.; Bogaerts, A. |
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Title |
Cryogenic etching of silicon with SF6 inductively coupled plasmas: a combined modelling and experimental study |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
48 |
Issue |
48 |
Pages |
155204 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A hybrid Monte Carlofluid model is applied to simulate the wafer-temperature-dependent etching of silicon with SF6 inductively coupled plasmas (ICP). The bulk plasma within the ICP reactor volume as well as the surface reactions occurring at the wafer are self-consistently described. The calculated etch rates are validated by experiments. The calculations and experiments are performed at two different wafer temperatures, i.e. 300 and 173 K, resembling conventional etching and cryoetching, respectively. In the case of cryoetching, a physisorbed SFx layer (x = 06) is formed on the wafer, which is negligible at room temperature, because of fast thermal desorption, However, even in the case of cryoetching, this layer can easily be disintegrated by low-energy ions, so it does not affect the etch rates. In the investigated pressure range of 19 Pa, the etch rate is always slightly higher at cryogenic conditions, both in the experiments and in the model, and this could be explained in the model due to a local cooling of the gas above the wafer, making the gas denser and increasing the flux of reactive neutrals, like F and F2, towards the wafer. |
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Thesis |
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Publisher |
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Place of Publication |
London |
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Language |
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Wos |
000351856600009 |
Publication Date |
2015-03-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
9 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2015 IF: 2.721 |
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Call Number |
c:irua:124209 |
Serial |
551 |
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Permanent link to this record |
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Author |
Shahraki, M.R.; Abedi-Sarvestani, A.; Seyedi, M.S.; Rafiaani Khachak, P.; Nieto-Garibay, A.; Van Passel, S.; Azadi, A. |
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Title |
The perception by pastoralists of the factors influencing the appropriate distribution of livestock in the rangelands of north-east Iran |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
The Rangeland Journal |
Abbreviated Journal |
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Volume |
37 |
Issue |
2 |
Pages |
191-197 |
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Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
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Abstract |
The distribution of livestock grazing is a key principle of range management. This study examines pastoralists perceptions of the factors that affect the distribution of livestock in the rangelands of the Neqab region of the Kashmar County in north-east Iran. Data were collected from the pastoralists on their perceptions of the managerial, biological and physical factors that influences the distribution of livestock, using both qualitative and quantitative assessments. Results showed that, the perception of the majority of pastoralists was that the distribution of livestock was average or good in the study area. It was perceived that the experience of herders and the size of the rangeland were the main factors influencing the distribution of livestock. Regression analyses showed that it was perceived that managerial factors had a more important role than biological and physical factors in the distribution of livestock and the proper use of the rangelands in north-east Iran. |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000351863200007 |
Publication Date |
2015-02-18 |
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Series Editor |
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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 |
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ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:129879 |
Serial |
6234 |
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Permanent link to this record |
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Author |
Leenaerts, O.; Schoeters, B.; Partoens, B. |
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Title |
Stable kagome lattices from group IV elements |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
91 |
Issue |
91 |
Pages |
115202 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A thorough investigation of three-dimensional kagome lattices of group IV elements is performed with first-principles calculations. The investigated kagome lattices of silicon and germanium are found to be of similar stability as the recently proposed carbon kagome lattice. Carbon and silicon kagome lattices are both direct-gap semiconductors but they have qualitatively different electronic band structures. While direct optical transitions between the valence and conduction bands are allowed in the carbon case, no such transitions can be observed for silicon. The kagome lattice of germanium exhibits semimetallic behavior but can be transformed into a semiconductor after compression. |
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Place of Publication |
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Language |
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Wos |
000351900700003 |
Publication Date |
2015-03-10 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
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Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). 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: 3.836; 2015 IF: 3.736 |
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Call Number |
c:irua:125516 |
Serial |
3144 |
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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 |
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Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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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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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
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 |
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Series Issue |
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Edition |
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ISSN |
1932-7447;1932-7455; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
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Call Number |
c:irua:125544 |
Serial |
171 |
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Permanent link to this record |
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Author |
Zhang, F.; Vanmeensel, K.; Batuk, M.; Hadermann, J.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J. |
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Title |
Highly-translucent, strong and aging-resistant 3Y-TZP ceramics for dental restoration by grain boundary segregation |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Acta biomaterialia |
Abbreviated Journal |
Acta Biomater |
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Volume |
16 |
Issue |
16 |
Pages |
215-222 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Latest trends in dental restorative ceramics involve the development of full-contour 3Y-TZP ceramics which can avoid chipping of veneering porcelains. Among the challenges are the low translucency and the hydrothermal stability of 3Y-TZP ceramics. In this work, different trivalent oxides (Al2O3, Sc2O3, Nd2O3 and La2O3) were selected to dope 3Y-TZP ceramics. Results show that dopant segregation was a key factor to design hydrothermally stable and high-translucent 3Y-TZP ceramics and the cation dopant radius could be used as a controlling parameter. A large trivalent dopant, oversized as compared to Zr4+, exhibiting strong segregation at the ZrO2 grain boundary was preferred. The introduction of 0.2 mol% La2O3 in conventional 0.10.25 wt.% Al2O3-doped 3Y-TZP resulted in an excellent combination of high translucency and superior hydrothermal stability, while retaining excellent mechanical properties. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
S.l. |
Editor |
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Language |
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Wos |
000351978600021 |
Publication Date |
2015-02-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1742-7061; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.319 |
Times cited |
54 |
Open Access |
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Notes |
Fwo G043110n |
Approved |
Most recent IF: 6.319; 2015 IF: 6.025 |
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Call Number |
c:irua:124421 |
Serial |
1473 |
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Permanent link to this record |
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Author |
Juchtmans, R.; Béché, A.; Abakumov, A.; Batuk, M.; Verbeeck, J. |
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Title |
Using electron vortex beams to determine chirality of crystals in transmission electron microscopy |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
91 |
Issue |
91 |
Pages |
094112 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We investigate electron vortex beams elastically scattered on chiral crystals. After deriving a general expression for the scattering amplitude of a vortex electron, we study its diffraction on point scatterers arranged on a helix. We derive a relation between the handedness of the helix and the topological charge of the electron vortex on one hand and the symmetry of the higher-order Laue zones in the diffraction pattern on the other for kinematically and dynamically scattered electrons. We then extend this to atoms arranged on a helix as found in crystals which belong to chiral space groups and propose a method to determine the handedness of such crystals by looking at the symmetry of the diffraction pattern. In contrast to alternative methods, our technique does not require multiple scattering, which makes it possible to also investigate extremely thin samples in which multiple scattering is suppressed. In order to verify the model, elastic scattering simulations are performed, and an experimental demonstration on Mn2Sb2O7 is given in which we find the sample to belong to the right-handed variant of its enantiomorphic pair. This demonstrates the usefulness of electron vortex beams to reveal the chirality of crystals in a transmission electron microscope and provides the required theoretical basis for further developments in this field. |
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Place of Publication |
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Language |
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Wos |
000352017000002 |
Publication Date |
2015-03-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
54 |
Open Access |
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Notes |
Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra1; esteem2jra2 ECASJO_; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
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Call Number |
c:irua:125512 c:irua:125512 |
Serial |
3825 |
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Permanent link to this record |
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Author |
Croitoru, M.D.; Buzdin, A.I. |
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Title |
FFLO-wave-vector lock-in effect in quasi-1D superconductors |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
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Volume |
28 |
Issue |
28 |
Pages |
1305-1308 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study the phase transition into the Fulde-Ferrell-Larkin-Ovchinnikov state in high magnetic field in quasi-one dimensional superconductors within the quasi-classical formalism, taking into account the interchain Josephson coupling and the paramagnetic spin splitting. We show that anomalies in the field-direction dependence of the upper critical field when the magnetic field length equals to the FFLO period, previously described in [29], are characterized by the lock-in effect of the FFLO modulation wave vector, which is governed by the magnetic length. |
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Publisher |
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Place of Publication |
New York, N.Y. |
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Language |
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Wos |
000352085700019 |
Publication Date |
2014-12-13 |
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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 |
1557-1939;1557-1947; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.18 |
Times cited |
4 |
Open Access |
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Notes |
; We thank D. Jerome for useful discussions. We acknowledge the support by the French ANR program “ElectroVortex” and European NanoSC COST Action MP1201. M.D.C. acknowledges the support by the BELSPO Return to Belgium Grant. ; |
Approved |
Most recent IF: 1.18; 2015 IF: 0.909 |
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Call Number |
c:irua:125540 |
Serial |
1187 |
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Permanent link to this record |
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Author |
Ayalew, E.; Gebre, Y.; De Wael, K. |
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Title |
A survey of occupational exposure to inhalable wood dust among workers in small- and medium-scale wood-processing enterprises in Ethiopia |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
The annals of occupational hygiene |
Abbreviated Journal |
Ann Occup Hyg |
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Volume |
59 |
Issue |
2 |
Pages |
253-257 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A study of wood dust exposure in 20 small- and medium-scale wood-processing enterprises was performed in Ethiopia. Sampling was conducted daily from January to June, 2013 and a total of 360 samples from 113 workers were collected with Institute of Occupational Medicine (IOM) personal samplers. Eight-hour time-weighted average exposure to wood dust ranged from 0.24 to 23.3mg m−3 with a geometric mean (GM) of 6.82mg m−3 and a geometric standard deviation of 1.82. Although Ethiopia did not have any defined standard of Occupational Exposure Limit for wood dust exposure, 71% of the measurements exceeded the limit of 5mg m−3 set by the European Union (EU). Higher than the EU exposure limit was measured while workers perform sanding and sawing activities with a GM of 9.72 and 7.60mg m−3, respectively. In conclusion, wood workers in the small- and medium-scale enterprises are at a higher risk of developing different respiratory health problems with continuous exposure trends. |
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Place of Publication |
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Language |
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Wos |
000352158700011 |
Publication Date |
2014-10-28 |
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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 |
0003-4878 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.71 |
Times cited |
4 |
Open Access |
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Notes |
; Eyasu Ayalew thanks the Addis Ababa University (Center for Environmental Sciences) for the personal grant for independent study. ; |
Approved |
Most recent IF: 1.71; 2015 IF: 2.101 |
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Call Number |
UA @ admin @ c:irua:119739 |
Serial |
5857 |
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Permanent link to this record |
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Author |
Roditchev, D.; Brun, C.; Serrier-Garcia, L.; Cuevas, J.C.; Bessa, V.H.L.; Milošević, M.V.; Debontridder, F.; Stolyarov, V.; Cren, T. |
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Title |
Direct observation of Josephson vortex cores |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
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Volume |
11 |
Issue |
11 |
Pages |
332-337 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Superconducting correlations may propagate between two superconductors separated by a tiny insulating or metallic barrier, allowing a dissipationless electric current to flow(1,2). In the presence of a magnetic field, the maximum supercurrent oscillates(3) and each oscillation corresponding to the entry of one Josephson vortex into the barrier(4). Josephson vortices are conceptual blocks of advanced quantum devices such as coherent terahertz generators(5) or qubits for quantum computing(6), in which on-demand generation and control is crucial. Here, we map superconducting correlations inside proximity Josephson junctions(7) using scanning tunnelling microscopy. Unexpectedly, we find that such Josephson vortices have real cores, in which the proximity gap is locally suppressed and the normal state recovered. By following the Josephson vortex formation and evolution we demonstrate that they originate from quantum interference of Andreev quasiparticles(8), and that the phase portraits of the two superconducting quantum condensates at edges of the junction decide their generation, shape, spatial extent and arrangement. Our observation opens a pathway towards the generation and control of Josephson vortices by applying supercurrents through the superconducting leads of the junctions, that is, by purely electrical means without any need for a magnetic field, which is a crucial step towards high-density on-chip integration of superconducting quantum devices. |
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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 |
000352163100016 |
Publication Date |
2015-02-23 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1745-2473;1745-2481; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
22.806 |
Times cited |
102 |
Open Access |
|
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|
Notes |
T.C., C.B., F.D., V.S. and D.R. acknowledge financial support from the French ANR project and the French-Russian program PICS-CNRS/RAS. The authors also thank V. Cherkez for assistance during experiments and V. Vinokur (Argonne National Laboratory, Illinois USA) and A. Buzdin (University of Bordeaux 1, France) for stimulating discussions. J.C.C. acknowledges financial support from the Spanish MICINN (Contract No. FIS2011-28851-C1). V.H.L.B. acknowledges support from CNPq Brazil and productive discussions with Prof. A. Chaves (UFC, Brazil). M.V.M. acknowledges support from Research Foundation Flanders (FWO-Vlaanderen) and CAPES Brazil (PVE project BEX1392/11-5). |
Approved |
Most recent IF: 22.806; 2015 IF: 20.147 |
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Call Number |
c:irua:132524 c:irua:132524 |
Serial |
3943 |
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Permanent link to this record |
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Author |
Batuk, D.; Batuk, M.; Abakumov, A.M.; Hadermann, J. |
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Title |
Synergy between transmission electron microscopy and powder diffraction : application to modulated structures |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Acta crystallographica: section B: structural science |
Abbreviated Journal |
Acta Crystallogr B |
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Volume |
71 |
Issue |
71 |
Pages |
127-143 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The crystal structure solution of modulated compounds is often very challenging, even using the well established methodology of single-crystal X-ray crystallography. This task becomes even more difficult for materials that cannot be prepared in a single-crystal form, so that only polycrystalline powders are available. This paper illustrates that the combined application of transmission electron microscopy (TEM) and powder diffraction is a possible solution to the problem. Using examples of anion-deficient perovskites modulated by periodic crystallographic shear planes, it is demonstrated what kind of local structural information can be obtained using various TEM techniques and how this information can be implemented in the crystal structure refinement against the powder diffraction data. The following TEM methods are discussed: electron diffraction (selected area electron diffraction, precession electron diffraction), imaging (conventional high-resolution TEM imaging, high-angle annular dark-field and annular bright-field scanning transmission electron microscopy) and state-of-the-art spectroscopic techniques (atomic resolution mapping using energy-dispersive X-ray analysis and electron energy loss spectroscopy). |
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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 |
Copenhagen |
Editor |
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Language |
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Wos |
000352166500002 |
Publication Date |
2015-04-01 |
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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 |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2052-5206; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.032 |
Times cited |
11 |
Open Access |
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Notes |
Fwo G039211n |
Approved |
Most recent IF: 2.032; 2015 IF: NA |
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Call Number |
c:irua:124411 |
Serial |
3408 |
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Permanent link to this record |
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Author |
E. Zaghi, A.; Buffière, M.; Koo, J.; Brammertz, G.; Batuk, M.; Verbist, C.; Hadermann, J.; Kim, W.K.; Meuris, M.; Poortmans, J.; Vleugels, J.; |
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Title |
Effect of selenium content of CuInSex alloy nanopowder precursors on recrystallization of printed CuInSe2 absorber layers during selenization heat treatment |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
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Volume |
|
Issue |
|
Pages |
1-7 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Polycrystalline CuInSe2 semiconductors are efficient light absorber materials for thin film solar cell technology, whereas printing is one of the promising low cost and non-vacuum approaches for the fabrication of thin film solar cells. The printed precursors are transformed into a dense polycrystalline CuInSe2 semiconductor film via thermal treatment in ambient selenium atmosphere (selenization). In this study, the effect of the selenium content in high purity mechanically synthesized CuInSex (x = 2, 1.5, 1 or 0.5) alloy precursors on the recrystallization of the CuInSe2 phase during the selenization process was investigated. The nanostructure and phase variation of CuInSex nanopowders were investigated by different characterization techniques. The recrystallization process of the 12 μm thick CuInSex coatings into the CuInSe2 phase during selenization in selenium vapor was investigated via in-situ high temperature X-ray diffraction. The CuInSex precursors with lower selenium content showed a more pronounced phase conversion into CuInSe2 compared to the higher selenium content CuInSex precursors. Moreover, the CuInSex (x = 0.5 and 1) precursor resulted in a denser polycrystalline CuInSe2 semiconductor film with larger crystals. This could be attributed to a more intensive atomic interdiffusion within the CuInSex precursor system compared to a CuInSe2 phase precursor, and the formation of intermediate CuSe and CuSe2 fluxing phases during selenization. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000352225900004 |
Publication Date |
2014-10-13 |
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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 |
0040-6090; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
1.879 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.879; 2014 IF: 1.759 |
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Call Number |
c:irua:121330 |
Serial |
834 |
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Permanent link to this record |
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Author |
Oueslati, S.; Brammertz, G.; Buffiere, M.; ElAnzeery, H.; Touayar, O.; Koeble, C.; Bekaert, J.; Meuris, M.; Poortmans, J. |
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Title |
Physical and electrical characterization of high-performance Cu2ZnSnSe4 based thin film solar cells |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
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|
Volume |
582 |
Issue |
582 |
Pages |
224-228 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We report on the electrical, optical and physical properties of Cu2ZnSnSe4 solar cells using an absorber layer fabricated by selenization of sputtered Cu, Zn and Cu10Sn90 multilayers. A maximum active-area conversion efficiency of 10.4% under AM1.5G was measured with a maximum short circuit current density of 39.7 mA/cm(2), an open circuit voltage of 394 mV and a fill factor of 66.4%. We perform electrical and optical characterization using photoluminescence spectroscopy, external quantum efficiency, current-voltage and admittance versus temperature measurements in order to derive information about possible causes for the low open circuit voltage values observed. The main defects derived from these measurements are strong potential fluctuations in the absorber layer as well as a potential barrier of the order of 133 meV at the back side contact. (C) 2014 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000352225900048 |
Publication Date |
2014-10-20 |
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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 |
|
Series Issue |
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Edition |
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ISSN |
0040-6090 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.879 |
Times cited |
49 |
Open Access |
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Notes |
; We would like to acknowledge Tom De Geyter, Greetje Godiers, and Guido Huyberechts from Flamac in Gent for sputtering of the metal layers. AGC is acknowledged for providing substrates. This research is partially funded by the Flemish government, Department Economy, Science and Innovation. ; |
Approved |
Most recent IF: 1.879; 2015 IF: 1.759 |
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Call Number |
UA @ lucian @ c:irua:132504 |
Serial |
4225 |
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Permanent link to this record |
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Author |
Bertrand, L.; Schoeeder, S.; Anglos, D.; Breese, M.B.H.; Janssens, K.; Moini, M.; Simon, A. |
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Title |
Mitigation strategies for radiation damage in the analysis of ancient materials |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Trends in analytical chemistry |
Abbreviated Journal |
Trac-Trend Anal Chem |
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Volume |
66 |
Issue |
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Pages |
128-145 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The study of materials in cultural heritage artifacts and micro-samples benefits from diagnostic techniques based on intense radiation sources, such as synchrotrons, ion-beam accelerators and lasers. While most of the corresponding techniques are classified as non-destructive, investigation with photons or charged particles entails a number of fundamental processes that may induce changes in materials. These changes depend on irradiation parameters, properties of materials and environmental factors. In some cases, radiation-induced damage may be detected by visual inspection. When it is not, irradiation may still lead to atomic and molecular changes resulting in immediate or delayed alteration and bias of future analyses. Here we review the effects of radiation reported on a variety of cultural heritage materials and describe the usual practice for assessing short-term and long-term effects. This review aims to raise awareness and encourage subsequent research activities to limit radiation side effects. |
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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 |
000352248200020 |
Publication Date |
2014-12-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0165-9936 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.442 |
Times cited |
35 |
Open Access |
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Notes |
; We wish to acknowledge the support of this initiative by the International Atomic Energy Agency. We gratefully thank Professor Manfred Schreiner of the Institute of Natural Sciences and Technology in the Arts (Akademie den bildenden Kunst, Vienna, Austria) for helpful discussions and insights on this work. We thank all colleagues who accepted to have their work reproduced in this review. IPANEMA at Synchrotron SOLEIL, the Hungarian Academy of Science and IESL-FORTH were supported within the Research Infrastructure program CHARISMA of the 7th Framework Programme of the EU (Grant Agreement no. 228330). MM's contribution is based upon work supported by the National Science Foundation under Grant numbers CHE 1241672 and CHE 1440849. We thank Chris McGlinchey and Lauren Klein (Museum of Modern Art, New York, USA) for their critical rereading of the manuscript. ; |
Approved |
Most recent IF: 8.442; 2015 IF: 6.472 |
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Call Number |
UA @ admin @ c:irua:124627 |
Serial |
5729 |
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Permanent link to this record |
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Author |
Kuopanportti, P.; Orlova, N.V.; Milošević, M.V. |
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Title |
Ground-state multiquantum vortices in rotating two-species superfluids |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
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Volume |
91 |
Issue |
91 |
Pages |
043605 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We show numerically that a rotating, harmonically trapped mixture of two Bose-Einstein-condensed superfluids cancontrary to its single-species counterpartcontain a multiply quantized vortex in the ground state of the system. This giant vortex can occur without any accompanying single-quantum vortices, may either be coreless or have an empty core, and can be realized in a Rb87−K41 Bose-Einstein condensate. Our results not only provide a rare example of a stable, solitary multiquantum vortex but also reveal exotic physics stemming from the coexistence of multiple, compositionally distinct condensates in one system. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000352255200005 |
Publication Date |
2015-04-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1050-2947;1094-1622; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.925 |
Times cited |
25 |
Open Access |
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Notes |
; This work was supported by the Finnish Cultural Foundation, the Research Foundation – Flanders (FWO), and the Magnus Ehrnrooth Foundation. We thank E. Ruokokoski and T. P. Simula for valuable comments and discussions. ; |
Approved |
Most recent IF: 2.925; 2015 IF: 2.808 |
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Call Number |
c:irua:124906 |
Serial |
1388 |
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Permanent link to this record |
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Author |
Li, M.R.; Croft, M.; Stephens, P.W.; Ye, M.; Vanderbilt, D.; Retuerto, M.; Deng, Z.; Grams, C.P.; Hemberger, J.; Hadermann, J.; Li, W.M.; Jin, C.Q.; Saouma, F.O.; Jang, J.I.; Akamatsu, H.; Gopalan, V.; Walker, D.; Greenblatt, M.; |
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Title |
Mn2FeWO6 : a new Ni3TeO6-type polar and magnetic oxide |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
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Volume |
27 |
Issue |
27 |
Pages |
2177-2181 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Mn22+Fe2+W6+O6, a new polar magnetic phase, adopts the corundum-derived Ni3TeO6-type structure with large spontaneous polarization (P-S) of 67.8 mu C cm-2, complex antiferromagnetic order below approximate to 75 K, and field-induced first-order transition to a ferrimagnetic phase below approximate to 30 K. First-principles calculations predict a ferrimagnetic (udu) ground state, optimal switching path along the c-axis, and transition to a lower energy udu-udd magnetic double cell. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000352548900004 |
Publication Date |
2015-02-13 |
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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 |
0935-9648; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
19.791 |
Times cited |
32 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 19.791; 2015 IF: 17.493 |
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Call Number |
c:irua:126002 |
Serial |
3545 |
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Permanent link to this record |
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Author |
Pavlović, S.; Peeters, F.M. |
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Title |
Electronic properties of triangular and hexagonal MoS2 quantum dots |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
91 |
Issue |
91 |
Pages |
155410 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using the tight-binding approach, we calculate the electronic structure of triangular and hexagonal MoS2 quantum dots. Due to the orbital asymmetry we show that it is possible to form quantum dots with the same shape but having different electronic properties. The electronic states of triangular and hexagonal quantum dots are explored, as well as the local and total density of states and the convergence towards the bulk spectrum with dot size is investigated. Our calculations show that: (1) edge states appear in the band gap, (2) that there are a larger number of electronic states in the conduction band as compared to the valence band, and (3) the relative number of edge states decreases with increasing dot size. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000352591200005 |
Publication Date |
2015-04-11 |
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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 |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
44 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the Methusalem Foundation of the Flemish government. Stefan Pavlovic is supported by JoinEU-SEE IV, Erasmus Mundus Action 2 programme. We thank J. M. Pereira for interesting discussions. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
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Call Number |
UA @ lucian @ c:irua:132516 |
Serial |
4170 |
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Permanent link to this record |
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Author |
Tang, T.; Boenne, W.; Desmet, N.; Seuntjens, P.; Bronders, J.; van Griensven, A. |
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Title |
Quantification and characterization of glyphosate use and loss in a residential area |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
The science of the total environment |
Abbreviated Journal |
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Volume |
517 |
Issue |
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Pages |
207-214 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Urban runoff can be a significant source of pesticides in urban streams. However, quantification of this source has been difficult because pesticide use by urban residents (e.g., on pavements or in gardens) is often unknown, particularly at the scale of a residential catchment. Proper quantification and characterization of pesticide loss via urban runoff require sound information on the use and occurrence of pesticides at hydrologically-relevant spatial scales, involving various hydrological conditions. We conducted a monitoring study in a residential area (9.5 ha, Flanders, Belgium) to investigate the use and loss of a widely-used herbicide (glyphosate) and its major degradation product (aminomethylphosphonic acid, AMPA). The study covered 13 rainfall events over 67 days. Overall, less than 0.5% of glyphosate applied was recovered from the storm drain outflow in the catchment. Maximum detected concentrations were 6.1 mu g/L and 5.8 mu g/L for glyphosate and AMPA, respectively, both of which are below the predicted no-effect concentration for surface water proposed by the Flemish environmental agency (10 mu g/L), but are above the EU drinking water standard (0.1 mu g/L). The measured concentrations and percentage loss rates can be attributed partially to the strong sorption capacity of glyphosate and low runoff potential in the study area. However, glyphosate loss varied considerably among rainfall events and event load of glyphosate mass was mainly controlled by rainfall amount, according to further statistical analyses. To obtain urban pesticide management insights, robust tools are required to investigate the loss and occurrence of pesticides influenced by various factors, particularly the hydrological and spatial factors. (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 |
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Place of Publication |
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Editor |
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Language |
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Wos |
000352663800020 |
Publication Date |
2015-02-27 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
0048-9697; 1879-1026 |
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 |
|
Approved |
no |
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Call Number |
UA @ admin @ c:irua:125992 |
Serial |
8431 |
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Permanent link to this record |
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Author |
Guerrero, A.; Heidari, H.; Ripolles, T.S.; Kovalenko, A.; Pfannmöller, M.; Bals, S.; Kauffmann, L.-D.; Bisquert, J.; Garcia-Belmonte, G. |
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Title |
Shelf life degradation of bulk heterojunction solar cells : intrinsic evolution of charge transfer complex |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Laser physics review |
Abbreviated Journal |
Adv Energy Mater |
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Volume |
5 |
Issue |
5 |
Pages |
1401997 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Achievement of long-term stability of organic photovoltaics is currently one of the major topics for this technology to reach maturity. Most of the techniques used to reveal degradation pathways are destructive and/or do not allow for real-time measurements in operating devices. Here, three different, nondestructive techniques able to provide real-time information, namely, film absorbance, capacitance-voltage (C-V), and impedance spectroscopy (IS), are combined over a period of 1 year using non-accelerated intrinsic degradation conditions. It is discerned between chemical modifications in the active layer, physical processes taking place in the bulk of the blend from those at the active layer/contact interfaces. In particular, it is observed that during the ageing experiment, the main source for device performance degradation is the formation of donor-acceptor charge-transfer complex (P3HT(center dot+)-PCBM center dot-) that acts as an exciton quencher. Generation of these radical species diminishes photocurrent and reduces open-circuit voltage by the creation of electronic defect states. Conclusions extracted from absorption, C-V, and IS measurements will be further supported by a range of other techniques such as atomic force microscopy, X-ray diffraction, and dark-field imaging of scanning transmission electron microscopy on ultrathin cross-sections. |
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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 |
S.l. |
Editor |
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Language |
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Wos |
000352708600013 |
Publication Date |
2014-12-12 |
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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 |
1614-6832; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
16.721 |
Times cited |
30 |
Open Access |
OpenAccess |
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|
Notes |
287594 Sunflower; 335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 16.721; 2015 IF: 16.146 |
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Call Number |
c:irua:126000 |
Serial |
2994 |
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Permanent link to this record |
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Author |
De Schouwer, F.; Claes, L.; Claes, N.; Bals, S.; Degrève, J.; De Vos, D.E. |
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Title |
Pd-catalyzed decarboxylation of glutamic acid and pyroglutamic acid to bio-based 2-pyrrolidone |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Green chemistry : cutting-edge research for a greener sustainable future |
Abbreviated Journal |
Green Chem |
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Volume |
17 |
Issue |
17 |
Pages |
2263-2270 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In order to recycle nitrogen from nitrogen-rich waste streams, particularly protein waste, we studied the decarboxylation of pyroglutamic acid and glutamic acid in a one-pot reaction to bio-based 2-pyrrolidone. After the screening of a wide range of supported Pd and Pt catalysts, 5 wt% Pd/Al2O3 displayed the highest yield (70%) and selectivity (81%) for the decarboxylation of pyroglutamic acid in water at 250 °C and under an inert atmosphere. Side products originate from consecutive reactions of 2-pyrrolidone; different reaction pathways are proposed to explain the presence of degradation products like propionic acid, γ-hydroxybutyric acid, γ-butyrolactone and methylamine. An extensive study of the reaction parameters was performed to check their influence on selectivity and conversion. This heterogeneous catalytic system was successfully extended to the conversion of glutamic acid. |
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Place of Publication |
London |
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Wos |
000352724200027 |
Publication Date |
2015-02-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9262;1463-9270; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.125 |
Times cited |
47 |
Open Access |
OpenAccess |
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Notes |
335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 9.125; 2015 IF: 8.020 |
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Call Number |
c:irua:125378 |
Serial |
2564 |
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Permanent link to this record |
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Author |
Snoeckx, R.; Zeng, Y.X.; Tu, X.; Bogaerts, A. |
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Title |
Plasma-based dry reforming : improving the conversion and energy efficiency in a dielectric barrier discharge |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
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Volume |
5 |
Issue |
5 |
Pages |
29799-29808 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Dry reforming of methane has gained significant interest over the years. A novel reforming technique with great potential is plasma technology. One of its drawbacks, however, is energy consumption. Therefore, we performed an extensive computational study, supported by experiments, aiming to identify the influence of the operating parameters (gas mixture, power, residence time and frequency) of a dielectric barrier discharge plasma on the conversion and energy efficiency, and to investigate which of these parameters lead to the most promising results and whether these are eventually sufficient for industrial implementation. The best results, in terms of both energy efficiency and conversion, are obtained at a specific energy input (SEI) of 100 J cm−3, a 1090 CH4CO2 ratio, 10 Hz, a residence time of 1 ms, resulting in a total conversion of 84% and an energy efficiency of 8.5%. In general, increasing the CO2 content in the gas mixture leads to a higher conversion and energy efficiency. The SEI couples the effect of the power and residence time, and increasing the SEI always results in a higher conversion, but somewhat lower energy efficiencies. The effect of the frequency is more complicated: we observed that the product of frequency (f) and residence time (τ), being a measure for the total number of micro-discharge filaments which the gas molecules experience when passing through the reactor, was critical. For most cases, a higher number of filaments yields higher values for conversion and energy efficiency. To benchmark our model predictions, we also give an overview of measured conversions and energy efficiencies reported in the literature, to indicate the potential for improvement compared to the state-of-the art. Finally, we identify the limitations as well as the benefits and future possibilities of plasma technology. |
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Place of Publication |
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Wos |
000352789500026 |
Publication Date |
2015-03-19 |
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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 |
2046-2069; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.108 |
Times cited |
67 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.108; 2015 IF: 3.840 |
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Call Number |
c:irua:132577 |
Serial |
2629 |
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Permanent link to this record |
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Author |
Sahin, H.; Leenaerts, O.; Singh, S.K.; Peeters, F.M. |
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Title |
Graphane |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Wiley Interdisciplinary Reviews: Computational Molecular Science |
Abbreviated Journal |
Wires Comput Mol Sci |
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Volume |
5 |
Issue |
5 |
Pages |
255-272 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Atomically thin crystals have recently been the focus of attention, in particular, after the synthesis of graphene, a monolayer hexagonal crystal structure of carbon. In this novel material class, the chemically derived graphenes have attracted tremendous interest. It was shown that, although bulk graphite is a chemically inert material, the surface of single layer graphene is rather reactive against individual atoms. So far, synthesis of several graphene derivatives have been reported such as hydrogenated graphene graphane' (CH), fluorographene (CF), and chlorographene (CCl). Moreover, the stability of bromine and iodine covered graphene were predicted using computational tools. Among these derivatives, easy synthesis, insulating electronic behavior and reversibly tunable crystal structure of graphane make this material special for future ultra-thin device applications. This overview surveys structural, electronic, magnetic, vibrational, and mechanical properties of graphane. We also present a detailed overview of research efforts devoted to the computational modeling of graphane and its derivatives. Furthermore recent progress in synthesis techniques and possible applications of graphane are reviewed as well. WIREs Comput Mol Sci 2015, 5:255-272. doi: 10.1002/wcms.1216 For further resources related to this article, please visit the . Conflict of interest: The authors have declared no conflicts of interest for this article. |
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Wos |
000352862700001 |
Publication Date |
2015-03-12 |
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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 |
1759-0876; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
14.016 |
Times cited |
54 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. H. Sahin is supported by a FWO Pegasus Long Marie Curie Fellowship. ; |
Approved |
Most recent IF: 14.016; 2015 IF: 11.885 |
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Call Number |
c:irua:125996 |
Serial |
1366 |
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Permanent link to this record |
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Author |
Bretos, I.; Schneller, T.; Falter, M.; Baecker, M.; Hollmann, E.; Woerdenweber, R.; Molina-Luna, L.; Van Tendeloo, G.; Eibl, O. |
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Title |
Solution-derived YBa2Cu3O7-\delta (YBCO) superconducting films with BaZrO3 (BZO) nanodots based on reverse micelle stabilized nanoparticles |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of materials chemistry C : materials for optical and electronic devices |
Abbreviated Journal |
J Mater Chem C |
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Volume |
3 |
Issue |
3 |
Pages |
3971-3979 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Superconducting YBa2Cu3O7-delta (YBCO) films with artificial BaZrO3 (BZO) nanodots were prepared using a chemical solution deposition method involving hybrid solutions composed of trifluoroacetate-based YBCO precursors and reverse micelle stabilized BZO nanoparticle dispersions. Microemulsion-mediated synthesis was used to obtain nano-sized (similar to 12 nm) and mono-dispersed BZO nanoparticles that preserve their features once introduced into the YBCO solution, as revealed by dynamic light scattering. Phase pure, epitaxial YBCO films with randomly oriented BZO nanodots distributed over their whole microstructure were grown from the hybrid solutions on (100) LaAlO3 substrates. The morphology of the YBCO-BZO nanocomposite films was strongly influenced by the amount of nanoparticles incorporated into the system, with contents ranging from 5 to 40 mol%. Scanning electron microscopy showed a high density of isolated second-phase defects consisting of BZO nanodots in the nanocomposite film with 10 mol% of BZO. Furthermore, a direct observation and quantitative analysis of lattice defects in the form of interfacial edge dislocations directly induced by the BZO nanodots was evidenced by transmission electron microscopy. The superconducting properties (77 K) of the YBCO films improved considerably by the presence of such nanodots, which seem to enhance the morphology of the sample and therefore the intergranular critical properties. The incorporation of preformed second-phase defects (here, BZO) during the growth of the superconducting phase is the main innovation of this novel approach for the all-solution based low-cost fabrication of long-length coated conductors. |
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Place of Publication |
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Language |
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Wos |
000352870400018 |
Publication Date |
2015-03-06 |
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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 |
2050-7526; 2050-7534 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.256 |
Times cited |
19 |
Open Access |
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Notes |
This work was supported by the German Federal Ministry of Economics and Technology (BMWi) contract no. 0327433A (project ELSA). L. Molina-Luna and G. Van Tendeloo acknowledge funding from the European Research Council (ERC grant no. 24691-COUNTATOMS). The authors gratefully acknowledge J. Dornseiffer for the support with preparation of the microemulsions for the BZO nanoparticles; G. Wasse for the SEM images; and T. Po¨ssinger for the preparation of the artwork. Eurotape |
Approved |
Most recent IF: 5.256; 2015 IF: 4.696 |
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Call Number |
UA @ lucian @ c:irua:132575 |
Serial |
4245 |
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Permanent link to this record |
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Author |
Van Gaens, W.; Iseni, S.; Schmidt-Bleker, A.; Weltmann, K.-D.; Reuter, S.; Bogaerts, A. |
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Title |
Numerical analysis of the effect of nitrogen and oxygen admixtures on the chemistry of an argon plasma jet operating at atmospheric pressure |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
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Volume |
17 |
Issue |
17 |
Pages |
033003 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this paper we study the cold atmospheric pressure plasma jet, called kinpen, operating in Ar with different admixture fractions up to 1% pure , and + . Moreover, the device is operating with a gas curtain of dry air. The absolute net production rates of the biologically active ozone () and nitrogen dioxide () species are measured in the far effluent by quantum cascade laser absorption spectroscopy in the mid-infrared. Additionally, a zero-dimensional semi-empirical reaction kinetics model is used to calculate the net production rates of these reactive molecules, which are compared to the experimental data. The latter model is applied throughout the entire plasma jet, starting already within the device itself. Very good qualitative and even quantitative agreement between the calculated and measured data is demonstrated. The numerical model thus yields very useful information about the chemical pathways of both the and the generation. It is shown that the production of these species can be manipulated by up to one order of magnitude by varying the amount of admixture or the admixture type, since this affects the electron kinetics significantly at these low concentration levels. |
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Place of Publication |
Bristol |
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Wos |
000352898500003 |
Publication Date |
2015-03-03 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1367-2630; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.786 |
Times cited |
29 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.786; 2015 IF: 3.558 |
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Call Number |
c:irua:124228 |
Serial |
2391 |
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Permanent link to this record |
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Author |
Lu, Y.-G.; Turner, S.; Ekimov, E.A.; Verbeeck, J.; Van Tendeloo, G. |
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Title |
Boron-rich inclusions and boron distribution in HPHT polycrystalline superconducting diamond |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
86 |
Issue |
86 |
Pages |
156-162 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Polycrystalline boron-doped superconducting diamond, synthesized at high pressure and high temperature (HPHT) via a reaction of a single piece of crystalline boron with monolithic graphite, has been investigated by analytical transmission electron microscopy. The local boron distribution and boron environment have been studied by a combination of (scanning) transmission electron microscopy ((S)TEM) and spatially resolved electron energy-loss spectroscopy (EELS). High resolution TEM imaging and EELS elemental mapping have established, for the first time, the presence of largely crystalline diamond-diamond grain boundaries within the material and have evidenced the presence of substitutional boron dopants within individual diamond grains. Confirmation of the presence of substitutional B dopants has been obtained through comparison of acquired boron K-edge EELS fine structures with known references. This confirmation is important to understand the origin of superconductivity in polycrystalline B-doped diamond. In addition to the substitutional boron doping, boron-rich inclusions and triple-points, both amorphous and crystalline, with chemical compositions close to boron carbide B4C, are evidenced. (C) 2015 Elsevier Ltd. All rights reserved. |
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Place of Publication |
Oxford |
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Wos |
000352922700019 |
Publication Date |
2015-01-22 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0008-6223; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.337 |
Times cited |
20 |
Open Access |
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Notes |
FWO; 246791 COUNTATOMS; 278510 VORTEX; Hercules ECASJO_; |
Approved |
Most recent IF: 6.337; 2015 IF: 6.196 |
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Call Number |
c:irua:125994UA @ admin @ c:irua:125994 |
Serial |
250 |
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Permanent link to this record |
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Author |
Nishio, K.; Lu, A.K.A.; Pourtois, G. |
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Title |
Low-strain Si/O superlattices with tunable electronic properties : ab initio calculations |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
91 |
Issue |
91 |
Pages |
165303 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
We propose that low-strain Si/O superlattices can be constructed by connecting reconstructed Si{001} surfaces by Si-O-Si bridges. Ab initio calculations show that our models are energetically more favorable than all the models proposed so far. The part of our Si/O superlattice model is experimentally accessible just by oxidizing a Si( 001) substrate. To complete our Si/O superlattice model, we propose a three-step method. We also explore the potential of our Si/O superlattice models for new materials used in future Si electronics. We find that the location of the channel where the carriers travel can be controlled between the interfaces and the Si layers by the insertion of O atoms into the Si-Si dimers. By revealing the origins of the interface electron and hole states, we find that similar interface states should be easily achieved for Si slabs and Si substrates. Interestingly, the interface electrons and holes have small effective masses in the direction parallel to the channel and large effective masses in the direction normal to the channel, which makes the Si/O superlattices attractive to be used for channel materials. We also find that the valley splitting of Si is enhanced by the formation of the Si/O/Si interfaces, which is ideal for developing Si-based qubits. Our findings open new perspectives to design and control the electronic properties of Si. |
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Wos |
000352986700002 |
Publication Date |
2015-04-16 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
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Call Number |
c:irua:125998 |
Serial |
1852 |
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Permanent link to this record |
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Author |
Shanenko, A.A.; Aguiar, J.A.; Vagov, A.; Croitoru, M.D.; Milošević, M.V. |
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Title |
Atomically flat superconducting nanofilms: multiband properties and mean-field theory |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
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Volume |
28 |
Issue |
28 |
Pages |
054001 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Recent progress in materials synthesis enabled fabrication of superconducting atomically flat single-crystalline metallic nanofilms with thicknesses down to a few monolayers. Interest in such nano-thin systems is attracted by the dimensional 3D-2D crossover in their coherent properties which occurs with decreasing the film thickness. The first fundamental aspect of this crossover is dictated by the Mermin-Wagner-Hohenberg theorem and concerns frustration of the long-range order due to superconductive fluctuations and the possibility to track its impact with an unprecedented level of control. The second important aspect is related to the Fabri-Perot modes of the electronic motion strongly bound in the direction perpendicular to the nanofilm. The formation of such modes results in a pronounced multiband structure that changes with the nanofilm thickness and affects both the mean-field behavior and superconductive fluctuations. Though the subject is very rich in physics, it is scarcely investigated to date. The main obstacle is that there are no manageable models to study a complex magnetic response in this case. Full microscopic consideration is rather time consuming, if practicable at all, while the standard Ginzburg-Landau theory is not applicable. In the present work we review the main achievements in the subject to date, and construct and justify an efficient multiband mean-field formalism which allows for numerical and even analytical treatment of nano-thin superconductors in applied magnetic fields. |
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Place of Publication |
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Language |
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Wos |
000353015700005 |
Publication Date |
2015-03-19 |
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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 |
0953-2048;1361-6668; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.878 |
Times cited |
23 |
Open Access |
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Notes |
This work was supported by the Brazilian agencies CNPq (grants 307552/2012-8 and 141911/2012-3) and FACEPE (APQ-0589-1.05/08). AAS acknowledges fruitful discussions with A Perali and D Neilson during his stay in the University of Camerino and is thankful for partial support of his visit by the University of Camerino under the project FAR 'Control and enhancement of superconductivity by engineering materials at the nanoscale'. MDC acknowledges the support from the Back to Belgium Grant of the federal Science Policy (BELSPO). |
Approved |
Most recent IF: 2.878; 2015 IF: 2.325 |
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Call Number |
c:irua:132501 |
Serial |
3944 |
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Permanent link to this record |
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Author |
Michel, K.H.; Costamagna; Peeters, F.M. |
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Title |
Theory of anharmonic phonons in two-dimensional crystals |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
91 |
Issue |
91 |
Pages |
134302 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Anharmonic effects in an atomic monolayer thin crystal with honeycomb lattice structure are investigated by analytical and numerical lattice dynamical methods. Starting from a semiempirical model for anharmonic couplings of third and fourth orders, we study the in-plane and out-of-plane (flexural) mode components of the generalized wave vector dependent Gruneisen parameters, the thermal tension and the thermal expansion coefficients as a function of temperature and crystal size. From the resonances of the displacement-displacement correlation functions, we obtain the renormalization and decay rate of in-plane and flexural phonons as a function of temperature, wave vector, and crystal size in the classical and in the quantum regime. Quantitative results are presented for graphene. There, we find that the transition temperature T-alpha from negative to positive thermal expansion is lowered with smaller system size. Renormalization of the flexural mode has the opposite effect and leads to values of T-alpha approximate to 300 K for systems of macroscopic size. Extensive numerical analysis throughout the Brillouin zone explores various decay and scattering channels. The relative importance of normal and umklapp processes is investigated. The work is complementary to crystalline membrane theory and computational studies of anharmonic effects in two-dimensional crystals. |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000353031000001 |
Publication Date |
2015-04-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121; 1550-235x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
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Notes |
; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the EuroGRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
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Call Number |
UA @ lucian @ c:irua:132512 |
Serial |
4263 |
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Permanent link to this record |
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Author |
Vasylenko, A.A.; Misko, V.R. |
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Title |
Nonlinear transport of the Wigner crystal in symmetric and asymmetric FET-like structures : nonlinear transport of the Wigner crystal on superfluid He-4 in quasi-one-dimensional channels with symmetric and asymmetric constrictions |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
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Volume |
88 |
Issue |
88 |
Pages |
105 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
When floating on a two-dimensional surface of superfluid He-4, electrons arrange themselves in two-dimensional crystalline structure known as Wigner crystal. In channels, the boundaries interfere the crystalline order and in case of very narrow channels one observes a quasi-one-dimensional (quasi-1D) Wigner crystal formed by just a few rows of electrons and, ultimately, one row in the “quantum wire” regime. Recently, the “quantum wire” regime was accessed experimentally [D.G. Rees, H. Totsuji, K. Kono, Phys. Rev. Lett. 108, 176801 (2012)] resulting in unusual transport phenomena such as, e.g., oscillations in the electron conductance. Using molecular dynamics simulations, we study the nonlinear transport of electrons in channels with various types of constrictions: single and multiple symmetric and asymmetric geometrical constrictions with varying width and length, and saddle-point-type potentials with varying gate voltage. In particular, we analyze the average particle velocity of the particles and the corresponding electron current versus the driving force or the gate voltage. We have revealed a significant difference in the dynamics for long and short constrictions: The oscillations of the average velocity of the particles for the systems with short constrictions exhibit a clear correlation with the transitions between the states with different numbers of rows of particles; on the other hand, for the systems with longer constrictions these oscillations are suppressed. The obtained results qualitatively agree with the experimental observations. Next, we propose a FET-like structure that consists of a channel with asymmetric constrictions. We show that applying a transverse bias results either in increase of the average particle velocity or in its suppression thus allowing a flexible control tool over the electron transport. The advantage of the asymmetric FET is that it does not have a gate and it allows an easy control of relatively large electron flow. Furthermore, the asymmetric device can be used for rectification of an ac-driven electron flow. Our results bring important insights into the dynamics of electrons floating on the surface of superfluid He-4 in channels with constrictions and allow the effective control over the electron transport. |
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Berlin |
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Wos |
000353065100002 |
Publication Date |
2015-04-16 |
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1434-6028;1434-6036; |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.461 |
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Open Access |
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Approved |
Most recent IF: 1.461; 2015 IF: 1.345 |
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Call Number |
c:irua:125997 |
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2359 |
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