Records |
Author |
Lin, S.; Zhang, L.; Reddy, G.V.P.; Hui, C.; Gielis, J.; Ding, Y.; Shi, P. |
Title |
A geometrical model for testing bilateral symmetry of bamboo leaf with a simplified Gielis equation |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Ecology and evolution |
Abbreviated Journal |
|
Volume |
6 |
Issue |
19 |
Pages |
6798-6806 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The size and shape of plant leaves change with growth, and an accurate description of leaf shape is crucial for describing plant morphogenesis and development. Bilateral symmetry, which has been widely observed but poorly examined, occurs in both dicot and monocot leaves, including all nominated bamboo species (approximately 1,300 species), of which at least 500 are found in China. Although there are apparent differences in leaf size among bamboo species due to genetic and environmental profiles, bamboo leaves have bilateral symmetry with parallel venation and appear similar across species. Here, we investigate whether the shape of bamboo leaves can be accurately described by a simplified Gielis equation, which consists of only two parameters (leaf length and shape) and produces a perfect bilateral shape. To test the applicability of this equation and the occurrence of bilateral symmetry, we first measured the leaf length of 42 bamboo species, examining >500 leaves per species. We then scanned 30 leaves per species that had approximately the same length as the median leaf length for that species. The leaf-shape data from scanned profiles were fitted to the simplified Gielis equation. Results confirmed that the equation fits the leaf-shape data extremely well, with the coefficients of determination being 0.995 on average. We further demonstrated the bilateral symmetry of bamboo leaves, with a clearly defined leaf-shape parameter of all 42 bamboo species investigated ranging from 0.02 to 0.1. This results in a simple and reliable tool for precise determination of bamboo species, with applications in forestry, ecology, and taxonomy. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000385626100003 |
Publication Date |
2016-09-02 |
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 |
2045-7758 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:144547 |
Serial |
7998 |
Permanent link to this record |
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Author |
Shi, P.; Liu, M.; Ratkowsky, D.A.; Gielis, J.; Su, J.; Yu, X.; Wang, P.; Zhang, L.; Lin, Z.; Schrader, J. |
Title |
Leaf area-length allometry and its implications in leaf shape evolution |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Trees: structure and function |
Abbreviated Journal |
|
Volume |
33 |
Issue |
4 |
Pages |
1073-1085 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
According to Thompson’s principle of similarity, the area of an object should be proportional to its length squared. However, leaf area–length data of some plants have been demonstrated not to follow the principle of similarity. We explore the reasons why the leaf area–length allometry deviates from the principle of similarity and examine whether there is a general model describing the relationship among leaf area, width and length. We sampled more than 11,800 leaves from six classes of woody and herbaceous plants and tested the leaf area–length allometry. We compared six mathematical models based on root-mean-square error as the measure of goodness-of-fit. The best supported model described a proportional relationship between leaf area and the product of leaf width and length (i.e., the Montgomery model). We found that the extent to which the leaf area–length allometry deviates from the principle of similarity depends upon the extent of variation of the ratio of leaf width to length. Estimates of the parameter of the Montgomery model ranged between 1/2, which corresponds to a triangular leaf with leaf length as its height and leaf width as its base, and π/4, which corresponds to an elliptical leaf with leaf length as its major axis and leaf width as its minor axis, for the six classes of plants. The narrow range in practice of the Montgomery parameter implies an evolutionary stability for the leaf area of large-leaved plants despite the fact that leaf shapes of these plants are rather different. |
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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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Wos |
000475992600010 |
Publication Date |
2019-04-04 |
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 |
0931-1890; 1432-2285 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:159970 |
Serial |
8170 |
Permanent link to this record |
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Author |
Zhang, L.; Vleugels, J.; Darchuk, L.; van der Biest, O. |
Title |
Magnetic field oriented tetragonal zirconia with anisotropic toughness |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of the European Ceramic Society |
Abbreviated Journal |
|
Volume |
31 |
Issue |
8 |
Pages |
1405-1412 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
(0 0 1)-oriented 3 mol% yttria stabilized tetragonal zirconia (3Y-TZP) has been developed by reactive synthesis of undoped pure monoclinic zirconia and co-precipitated 8 mol% yttria-stabilized zirconia (8Y-ZrO2). The dispersed pure monoclinic ZrO2 powder, having magnetic anisotropy, was first aligned in a strong magnetic field and co-sintered in a randomly distributed cubic 8Y-ZrO2 fine matrix powder. The reactive sintering resulted in a 3Y-TZP ceramic with a (0 0 1) orientation. The (0 0 1)-oriented 3Y-TZP showed a substantial toughness anisotropy, i.e. the toughness along the [0 0 1] direction is 54% higher than that of its perpendicular direction. Moreover, the toughness along the [0 0 1] direction is 49% higher than that of a non-textured isotropic reactively synthesized 3Y-TZP and 110% higher than that of an isotropic co-precipitated powder based 3Y-TZP. The substantially enhanced toughness was interpreted in terms of the tetragonal to monoclinic martensitic phase transformability. |
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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 |
000290189100008 |
Publication Date |
2011-03-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0955-2219 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:89722 |
Serial |
8192 |
Permanent link to this record |
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Author |
Lian, M.; Shi, P.; Zhang, L.; Yao, W.; Gielis, J.; Niklas, K.J. |
Title |
A generalized performance equation and its application in measuring the Gini index of leaf size inequality |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Trees: structure and function |
Abbreviated Journal |
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Volume |
37 |
Issue |
|
Pages |
1555-1565 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The goal of this study is to provide a rigorous tool to quantify the inequality of the leaf size distribution of an individual plant, thereby serving as a reference trait for quantifying plant adaptations to local environmental conditions. The tool to be presented and tested employs three components: (1) a performance equation (PE), which can produce flexible asymmetrical and symmetrical bell-shaped curves, (2) the Lorenz curve (i.e., the cumulative proportion of leaf size vs. the cumulative proportion of number of leaves), which is the basis for calculating, and (3) the Gini index, which measures the inequality of leaf size distribution. We sampled 12 individual plants of a dwarf bamboo and measured the area and dry mass of each leaf of each plant. We then developed a generalized performance equation (GPE) of which the PE is a special case and fitted the Lorenz curve to leaf size distribution using the GPE and PE. The GPE performed better than the PE in fitting the Lorenz curve. We compared the Gini index of leaf area distribution with that of leaf dry mass distribution and found that there was a significant difference between the two indices that might emerge from the scaling relationship between leaf dry mass and area. Nevertheless, there was a strong correlation between the two Gini indices (r2 = 0.9846). This study provides a promising tool based on the GPE for quantifying the inequality of leaf size distributions across individual plants and can be used to quantify plant adaptations to local environmental conditions. |
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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 |
001069570200001 |
Publication Date |
2023-08-26 |
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 |
0931-1890; 1432-2285 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.3 |
Times cited |
|
Open Access |
Not_Open_Access: Available from 26.02.2024 |
Notes |
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Approved |
Most recent IF: 2.3; 2023 IF: 1.842 |
Call Number |
UA @ admin @ c:irua:199562 |
Serial |
8874 |
Permanent link to this record |
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Author |
Li, Q.; Niklas, K.J.J.; Niinemets, U.; Zhang, L.; Yu, K.; Gielis, J.; Gao, J.; Shi, P. |
Title |
Stomatal shape described by a superellipse in four Magnoliaceae species |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Botany letters |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-9 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Stomata are essential for the exchange of water vapour and atmospheric gases between vascular plants and their external environments. The stomatal geometries of many plants appear to be elliptical. However, prior studies have not tested whether this is a mathematical reality, particularly since many natural shapes that appear to be ellipses are superellipses with greater or smaller edge curvature than predicted for an ellipse. Compared with the ellipse equation, the superellipse equation includes an additional parameter that allows generation of a larger range of shapes. We randomly selected 240 stomata from each of four Magnoliaceae species to test whether the stomatal geometries are superellipses or ellipses. The stomatal geometries for most stomata (943/960) were found to be described better using the superellipse equation. The traditional “elliptical stomata hypothesis” resulted in an underestimation of the area of stomata, whereas the superellipse equation accurately predicted stomatal area. This finding has important implications for the estimation of stomatal area in studies looking at stomatal shape, geometry, and function. |
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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 |
001024190300001 |
Publication Date |
2023-07-12 |
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 |
2381-8107; 2381-8115 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
1.5 |
Times cited |
|
Open Access |
Not_Open_Access: Available from 12.01.2024 |
Notes |
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Approved |
Most recent IF: 1.5; 2023 IF: NA |
Call Number |
UA @ admin @ c:irua:197847 |
Serial |
8935 |
Permanent link to this record |
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Author |
Zhang, L.; Quinn, B.K.; Hui, C.; Lian, M.; Gielis, J.; Gao, J.; Shi, P. |
Title |
New indices to balance α-diversity against tree size inequality |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Journal of forestry research |
Abbreviated Journal |
|
Volume |
35 |
Issue |
1 |
Pages |
31-39 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The number and composition of species in a community can be quantified with alpha-diversity indices, including species richness (R), Simpson's index (D), and the Shannon-Wiener index (HGREEK TONOS). In forest communities, there are large variations in tree size among species and individuals of the same species, which result in differences in ecological processes and ecosystem functions. However, tree size inequality (TSI) has been largely neglected in studies using the available diversity indices. The TSI in the diameter at breast height (DBH) data for each of 999 20 m x 20 m forest census quadrats was quantified using the Gini index (GI), a measure of the inequality of size distribution. The generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per quadrat. We also examined the relationships of alpha-diversity indices with the GI using correlation tests. The generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions, with most root-mean-square errors (990 out of 999 quadrats) being < 0.0030. There were significant positive correlations between each of three alpha-diversity indices (i.e., R, D, and H') and the GI. Nevertheless, the total abundance of trees in each quadrat did not significantly influence the GI. This means that the TSI increased with increasing species diversity. Thus, two new indices are proposed that can balance alpha-diversity against the extent of TSI in the community: (1 – GI) x D, and (1 – GI) x H'. These new indices were significantly correlated with the original D and HGREEK TONOS, and did not increase the extent of variation within each group of indices. This study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities, especially in the face of cumulative species loss under global climate change. |
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 |
001131698000001 |
Publication Date |
2023-12-28 |
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 |
1007-662x; 1993-0607 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
3 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 3; 2024 IF: 0.774 |
Call Number |
UA @ admin @ c:irua:201972 |
Serial |
9061 |
Permanent link to this record |
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Author |
Verbeeck, J.; Van Aert, S.; Zhang, L.; Haiyan, T.; Schattschneider, P.; Rosenauer, A. |
Title |
Computational aspects in quantitative EELS |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
16 |
Issue |
S:2 |
Pages |
240-241 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
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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 |
Cambridge, Mass. |
Editor |
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Language |
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Wos |
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Publication Date |
2010-08-26 |
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 |
1431-9276;1435-8115; |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
1.891 |
Times cited |
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Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.891; 2010 IF: 3.259 |
Call Number |
UA @ lucian @ c:irua:96556UA @ admin @ c:irua:96556 |
Serial |
454 |
Permanent link to this record |
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Author |
Mortet, V.; Zhang, L.; Eckert, M.; D'Haen, J.; Soltani, A.; Moreau, M.; Troadec, D.; Neyts, E.; De Jaeger, J.C.; Verbeeck, J.; Bogaerts, A.; Van Tendeloo, G.; Haenen, K.; Wagner, P. |
Title |
Grain size tuning of nanocrystalline chemical vapor deposited diamond by continuous electrical bias growth : experimental and theoretical study |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
Volume |
209 |
Issue |
9 |
Pages |
1675-1682 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this work, a detailed structural and spectroscopic study of nanocrystalline diamond (NCD) thin films grown by a continuous bias assisted CVD growth technique is reported. This technique allows the tuning of grain size and phase purity in the deposited material. The crystalline properties of the films are characterized by SEM, TEM, EELS, and Raman spectroscopy. A clear improvement of the crystalline structure of the nanograined diamond film is observed for low negative bias voltages, while high bias voltages lead to thin films consisting of diamond grains of only ∼10 nm nanometer in size, showing remarkable similarities with so-called ultrananocrystalline diamond. These layers arecharacterized by an increasing amount of sp2-bonded carbon content of the matrix in which the diamond grains are embedded. Classical molecular dynamics simulations support the observed experimental data, giving insight in the underlying mechanism for the observed increase in deposition rate with bias voltage. Furthermore, a high atomic concentration of hydrogen has been determined in these films. Finally, Raman scattering analyses confirm that the Raman line observed at ∼1150 cm−1 cannot be attributed to trans-poly-acetylene, which continues to be reported in literature, reassigning it to a deformation mode of CHx bonds in NCD. |
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 |
000308942100009 |
Publication Date |
2012-09-04 |
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 |
1862-6300; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.775 |
Times cited |
31 |
Open Access |
|
Notes |
M.E. and E.N. acknowledge financial support from, respectively, the Institute for Promotion of Innovation through Science and Technology in Flanders (IWT), and the Research Foundation-Flanders (FWO). J.V. gratefully acknowledges financial support from the GOA project “XANES meets ELNES” of the research fund of the University of Antwerp. Calculation support was provided by the University of Antwerp through the core facility CALCUA. G.V.T. acknowledges the ERC grant COUNTATOMS. The work was also financially supported by the joint UAUHasseltMethusalem “NANO” network, the Research Programs G.0068.07 and G.0555.10N of the Research Foundation-Flanders (FWO), the IAP-P6/42 project “Quantum Effects in Clusters and Nanowires”, and by the EU FP7 through the Integrated Infrastructure Initiative “ESMI” (No. 262348), the Marie Curie ITN “MATCON” (PITN-GA-2009-238201), and the Collaborative Project “DINAMO” (No. 245122). |
Approved |
Most recent IF: 1.775; 2012 IF: 1.469 |
Call Number |
UA @ lucian @ c:irua:101516UA @ admin @ c:irua:101516 |
Serial |
1364 |
Permanent link to this record |
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Author |
Afanasov, I.M.; Shornikova, O.N.; Kirilenko, D.A.; Vlasov, I.I.; Zhang, L.; Verbeeck, J.; Avdeev, V.V.; Van Tendeloo, G. |
Title |
Graphite structural transformations during intercalation by HNO3 and exfoliation |
Type |
L1 Letter to the editor |
Year |
2010 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
48 |
Issue |
6 |
Pages |
1862-1865 |
Keywords |
L1 Letter to the editor; Electron microscopy for materials research (EMAT) |
Abstract |
Expandable graphite of two types was synthesized by (1) hydrolysis of graphite nitrate of II stage and (2) anodic polarization of graphite in 60% HNO3. Exfoliated graphite samples were produced by thermal shock of expandable graphite samples in air at 900 °C. A comparative study of microstructural distinctions of both expandable and exfoliated graphite samples was carried out using X-ray diffraction, Raman spectroscopy, electron energy loss spectroscopy and high resolution transmission electron microscopy. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000276132800021 |
Publication Date |
2010-02-02 |
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 |
0008-6223; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
43 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 6.337; 2010 IF: 4.896 |
Call Number |
UA @ lucian @ c:irua:82315UA @ admin @ c:irua:82315 |
Serial |
1379 |
Permanent link to this record |
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Author |
Zhang, L.; Turner, S.; Brosens, F.; Verbeeck, J. |
Title |
Model-based determination of dielectric function by STEM low-loss EELS |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
3 |
Pages |
035102 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Theory of quantum systems and complex systems |
Abstract |
Dielectric properties of materials are crucial in describing the electromagnetic response of materials. As devices are becoming considerably smaller than the optical wavelength, the conventional measuring methods based on optical response are limited by their spatial resolution. Electron energy loss spectroscopy performed in a scanning transmission electron microscope is a good alternative to obtain the dielectric properties with excellent spatial resolution. Due to the overlap of diffraction discs in scanning transmission electron microscopy, it is difficult to apply conventional experimental settings to suppress retardation losses. In this contribution, a relativistic dielectric model for the loss function is presented which is used in a model based optimization scheme to estimate the complex dielectric function of a material. The method is applied to experiments on bulk diamond and SrTiO3 and shows a good agreement with optical reference data when retardation effects are included. Application of this technique to nanoparticles is possible but several theoretical assumptions made in the model of the loss function are violated and interpretation becomes problematic. |
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 |
000274002300027 |
Publication Date |
2010-01-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
Notes |
Esteem – 026019; Fwo |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:81258UA @ admin @ c:irua:81258 |
Serial |
2098 |
Permanent link to this record |
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Author |
Zhang, L.-F.; Covaci, L.; Peeters, F.M. |
Title |
Tomasch effect in nanoscale superconductors |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
91 |
Issue |
91 |
Pages |
024508 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The Tomasch effect (TE) is due to quasiparticle interference (QPI) as induced by a nonuniform superconducting order parameter, which results in oscillations in the density of states (DOS) at energies above the superconducting gap. Quantum confinement in nanoscale superconductors leads to an inhomogenerous distribution of the Cooperpair condensate, which, as we found, triggers the manifestation of a new TE. We investigate the electronic structure of nanoscale superconductors by solving the Bogoliubov-de Gennes (BdG) equations self-consistently and describe the TE determined by two types of processes, involving two-or three-subband QPIs. Both types of QPIs result in additional BCS-like Bogoliubov-quasiparticles and BCS-like energy gaps leading to oscillations in the DOS and modulated wave patterns in the local density of states. These effects are strongly related to the symmetries of the system. A reduced 4 x 4 inter-subband BdG Hamiltonian is established in order to describe analytically the TE of two-subband QPIs. Our study is relevant to nanoscale superconductors, either nanowires or thin films, Bose-Einsten condensates, and confined systems such as two-dimensional electron gas interface superconductivity. |
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 |
000348473700003 |
Publication Date |
2015-01-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Methusalem funding of the Flemish Government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
c:irua:123864 |
Serial |
3670 |
Permanent link to this record |
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Author |
Zhang, L.-F.; Covaci, L.; Milošević, M.V.; Berdiyorov, G.R.; Peeters, F.M. |
Title |
Vortex states in nanoscale superconducting squares : the influence of quantum confinement |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
88 |
Issue |
14 |
Pages |
144501 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Bogoliubov-de Gennes theory is used to investigate the effect of the size of a superconducting square on the vortex states in the quantum confinement regime. When the superconducting coherence length is comparable to the Fermi wavelength, the shape resonances of the superconducting order parameter have strong influence on the vortex configuration. Several unconventional vortex states, including asymmetric ones, giant-multivortex combinations, and states comprising giant antivortices, were found as ground states and their stability was found to be very sensitive on the value of k(F)xi(0), the size of the sample W, and the magnetic flux Phi. By increasing the temperature and/or enlarging the size of the sample, quantum confinement is suppressed and the conventional mesoscopic vortex states as predicted by the Ginzburg-Laudau (GL) theory are recovered. However, contrary to the GL results we found that the states containing symmetry-induced vortex-antivortex pairs are stable over the whole temperature range. It turns out that the inhomogeneous order parameter induced by quantum confinement favors vortex-antivortex molecules, as well as giant vortices with a rich structure in the vortex core-unattainable in the GL domain. |
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Wos |
000325498300004 |
Publication Date |
2013-10-09 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
19 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and Methusalem Funding of the Flemish government. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:111145 |
Serial |
3891 |
Permanent link to this record |
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Author |
Zhang, L.; Lin, B.-C.; Wu, Y.-F.; Wu, H.; Huang, T.-W.; Chang, C.-R.; Ke, X.; Kurttepeli, M.; Tendeloo, G.V.; Xu, J.; Yu, D.; Liao, Z.-M. |
Title |
Electronic Coupling between Graphene and Topological Insulator Induced Anomalous Magnetotransport Properties |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
11 |
Issue |
11 |
Pages |
6277-6285 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
It has been theoretically proposed that the spin textures of surface states in a topological insulator can be directly transferred to graphene by means of the proximity effect, which is very important for realizing the two-dimensional topological insulator based on graphene. Here we report the anomalous magnetotransport properties of graphene-topological insulator Bi2Se3 heterojunctions, which are sensitive to the electronic coupling between graphene and the topological surface state. The coupling between the p_z orbitals of graphene and the p orbitals of the surface states on the Bi2Se3 bottom surface can be enhanced by applying a perpendicular negative magnetic field, resulting in a giant negative magnetoresistance at the Dirac point up to about -91%. Obvious resistances dip in the transfer curve at the Dirac point is also observed in the hybrid devices, which is consistent with theoretical predictions of the distorted Dirac bands with nontrivial spin textures inherited from the Bi2Se3 surface states. |
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Wos |
000404808000110 |
Publication Date |
2017-05-10 |
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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 |
1936-0851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
12 |
Open Access |
OpenAccess |
Notes |
; This work was supported by National Key Research and Development Program of China (Nos. 2016YFA0300802, 2013CB934600) and NSFC (No. 11234001). ; |
Approved |
Most recent IF: 13.942 |
Call Number |
EMAT @ emat @ c:irua:143192 |
Serial |
4569 |
Permanent link to this record |
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Author |
Zhang, Q.-Z.; Tinck, S.; de Marneffe, J.-F.; Zhang, L.; Bogaerts, A. |
Title |
Mechanisms for plasma cryogenic etching of porous materials |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
111 |
Issue |
17 |
Pages |
173104 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Porous materials are commonly used in microelectronics, as they can meet the demand for continuously shrinking electronic feature dimensions. However, they are facing severe challenges in plasma etching, due to plasma induced damage. In this paper, we present both the plasma characteristics and surface processing during the etching of porous materials. We explain how the damage occurs in the porous material during plasma etching for a wide range of chuck temperatures and the responsible mechanism for plasma damage-free etching at cryogenic temperature, by a combination of experiments and numerical modeling. |
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Wos |
000413863400032 |
Publication Date |
2017-10-23 |
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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 |
0003-6951 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
2 |
Open Access |
OpenAccess |
Notes |
We acknowledge the support from Marie Skłodowska- Curie actions (Grant Agreement-702604). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the University of Antwerp. L. Zhang and J.-F. de Marneffe acknowledge Dr. M. Cooke and A. Goodyear from Oxford Instruments Plasma Technology for processing the samples at their Yatton facility in the United Kingdom. |
Approved |
Most recent IF: 3.411 |
Call Number |
PLASMANT @ plasmant @c:irua:147022 |
Serial |
4762 |
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Author |
Yang, C.; Batuk, M.; Jacquet, Q.; Rousse, G.; Yin, W.; Zhang, L.; Hadermann, J.; Abakumov, A.M.; Cibin, G.; Chadwick, A.; Tarascon, J.-M.; Grimaud, A. |
Title |
Revealing pH-Dependent Activities and Surface Instabilities for Ni-Based Electrocatalysts during the Oxygen Evolution Reaction |
Type |
A1 Journal article |
Year |
2018 |
Publication |
ACS energy letters |
Abbreviated Journal |
Acs Energy Lett |
Volume |
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Issue |
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Pages |
2884-2890 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Multiple electrochemical processes are involved at the catalyst/ electrolyte interface during the oxygen evolution reaction (OER). With the purpose of elucidating the complexity of surface dynamics upon OER, we systematically studied two Ni-based crystalline oxides (LaNiO3−δ and La2Li0.5Ni0.5O4) and compared them with the state-of-the-art Ni−Fe (oxy)- hydroxide amorphous catalyst. Electrochemical measurements such as rotating ring disk electrode (RRDE) and electrochemical quartz microbalance microscopy (EQCM) coupled with a series of physical characterizations including transmission electron microscopy (TEM) and X-ray absorption spectroscopy (XAS) were conducted to unravel the exact pH effect on both the OER activity and the catalyst stability. We demonstrate that for Ni-based crystalline catalysts the rate for surface degradation depends on the pH and is greater than the rate for surface reconstruction. This behavior is unlike that for the amorphous Ni oxyhydroxide catalyst, which is found to be more stable and pH-independent. |
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Wos |
000453805100005 |
Publication Date |
2018-11-08 |
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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 |
2380-8195 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
Not_Open_Access: Available from 06.11.2019
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Notes |
C.Y., J.-M.T., and A.G. acknowledge funding from the European Research Council (ERC) (FP/2014)/ERC GrantProject 670116-ARPEMA. A.G. acknowledges financial support from the ANR MIDWAY (Project ID ANR-17-CE05- 0008). We acknowledge Diamond Light Source for time awarded to the Energy Materials BAG on Beamline B18, under Proposal sp12559. |
Approved |
Most recent IF: NA |
Call Number |
EMAT @ emat @c:irua:155046 |
Serial |
5067 |
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Author |
Zhang, Q.‐Z.; Zhang, L.; Yang, D.‐Z.; Schulze, J.; Wang, Y.‐N.; Bogaerts, A. |
Title |
Positive and negative streamer propagation in volume dielectric barrier discharges with planar and porous electrodes |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Plasma Processes And Polymers |
Abbreviated Journal |
Plasma Process Polym |
Volume |
18 |
Issue |
4 |
Pages |
2000234 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The spatiotemporal dynamics of volume and surface positive and negative streamers in a pintoplate volume dielectric barrier discharge is investigated in this study. The discharge characteristics are found to be completely different for positive and negative streamers. First, the spatial propagation of a positive streamer is found to rely on electron avalanches caused by photo-electrons in front of the streamer head, whereas this is not the case for negative streamers. Second, our simulations reveal an interesting phenomenon of floating positive surface discharges, which develop when a positive streamer reaches a dielectric wall and which explain the experimentally observed branching characteristics. Third, we report for the first time, the interactions between a positive streamer and dielectric pores, in which both the pore diameter and depth affect the evolution of a positive streamer. |
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Wos |
000617876700001 |
Publication Date |
2021-02-17 |
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Series Issue |
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Edition |
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ISSN |
1612-8850 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.846 |
Times cited |
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Open Access |
OpenAccess |
Notes |
Dalian University of Technology, DUT19RC(3)045 ; National Natural Science Foundation of China, 12020101005 ; Deutsche Forschungsgemeinschaft, SFB 1316 project A5 ; Universiteit Antwerpen, TOP‐BOF ; The authors acknowledge financial support from the TOP-BOF project of the University of Antwerp. This study was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (Department EWI), and the University of Antwerp. Funding by the German Research Foundation (DFG) in the frame of the Collaborative Research Center SFB 1316, project A5, National Natural Science Foundation of China (No. 12020101005), and the Scientific Research Foundation from Dalian University of Technology (DUT19RC(3)045) is also acknowledged. |
Approved |
Most recent IF: 2.846 |
Call Number |
PLASMANT @ plasmant @c:irua:176565 |
Serial |
6744 |
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Author |
Zhang, L.; Heijkers, S.; Wang, W.; Martini, L.M.; Tosi, P.; Yang, D.; Fang, Z.; Bogaerts, A. |
Title |
Dry reforming of methane in a nanosecond repetitively pulsed discharge: chemical kinetics modeling |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Plasma Sources Science & Technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
31 |
Issue |
5 |
Pages |
055014 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Nanosecond pulsed discharge plasma shows a high degree of non-equilibrium, and exhibits relatively high conversions in the dry reforming of methane. To further improve the application, a good insight of the underlying mechanisms is desired. We developed a chemical kinetics model to explore the underlying plasma chemistry in nanosecond pulsed discharge. We compared the calculated conversions and product selectivities with experimental results, and found reasonable agreement in a wide range of specific energy input. Hence, the chemical kinetics model is able to provide insight in the underlying plasma chemistry. The modeling results predict that the most important dissociation reaction of CO<sub>2</sub>and CH<sub>4</sub>is electron impact dissociation. C<sub>2</sub>H<sub>2</sub>is the most abundant hydrocarbon product, and it is mainly formed upon reaction of two CH<sub>2</sub>radicals. Furthermore, the vibrational excitation levels of CO<sub>2</sub>contribute for 85% to the total dissociation of CO<sub>2</sub>. |
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Wos |
000797660000001 |
Publication Date |
2022-05-01 |
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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 |
0963-0252 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
3.8 |
Times cited |
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Open Access |
OpenAccess |
Notes |
China Scholarship Council; National Natural Science Foundation of China, 11965018 ; This work is supported by the National Natural Science Foundation of China (Grant Nos. 52077026, 11965018), L Zhang was also supported by the China Scholarship Council (CSC). Data availability statement The data that support the findings of this study are available upon reasonable request from the authors. |
Approved |
Most recent IF: 3.8 |
Call Number |
PLASMANT @ plasmant @c:irua:188537 |
Serial |
7069 |
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Author |
Parastaev, A.; Muravev, V.; Osta, E.H.; Kimpel, T.F.; Simons, J.F.M.; van Hoof, A.J.F.; Uslamin, E.; Zhang, L.; Struijs, J.J.C.; Burueva, D.B.; Pokochueva, E.V.; Kovtunov, K.V.; Koptyug, I.V.; Villar-Garcia, I.J.; Escudero, C.; Altantzis, T.; Liu, P.; Béché, A.; Bals, S.; Kosinov, N.; Hensen, E.J.M. |
Title |
Breaking structure sensitivity in CO2 hydrogenation by tuning metal–oxide interfaces in supported cobalt nanoparticles |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Nature Catalysis |
Abbreviated Journal |
Nat Catal |
Volume |
5 |
Issue |
11 |
Pages |
1051-1060 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
A high dispersion of the active metal phase of transition metals on oxide supports is important when designing efficient heterogeneous catalysts. Besides nanoparticles, clusters and even single metal atoms can be attractive for a wide range of reactions. However, many industrially relevant catalytic transformations suffer from structure sensitivity, where reducing the size of the metal particles below a certain size substantially lowers catalytic performance. A case in point is the low activity of small cobalt nanoparticles in the hydrogenation of CO and CO2. Here we show how engineering of catalytic sites at the metal–oxide interface in cerium oxide–zirconium dioxide (ceria–zirconia)-supported cobalt can overcome this structure sensitivity. Few-atom cobalt clusters dispersed on 3 nm cobalt(II)-oxide particles stabilized by ceria–zirconia yielded a highly active CO2 methanation catalyst with a specific activity higher than that of larger particles under the same conditions. |
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Place of Publication |
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Wos |
000884939300006 |
Publication Date |
2022-11-17 |
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 |
2520-1158 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
37.8 |
Times cited |
32 |
Open Access |
OpenAccess |
Notes |
This research was supported by the Applied and Engineering Sciences division of the Netherlands Organization for Scientific Research through the Alliander (now Qirion) Perspective program on Plasma Conversion of CO2. We acknowledge Diamond Light Source for time on beamline B18 under proposal SP20715-1. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. S.B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO) and T.A. acknowledges funding from the University of Antwerp Research fund (BOF). A.B. received funding from the European Union under grant agreement No 823717 – ESTEEM3. The authors acknowledge funding through the Hercules grant (FWO, University of Antwerp) I003218N “Infrastructure for imaging nanoscale processes in gas/vapour or liquid environments”. I.V.K., D.B.B., and E.V.P. acknowledge the Russian Ministry of Science and Higher Education (contract 075-15-2021-580) for financial support of parahydrogen-based studies. Experiments using synchrotron radiation XPS were performed at the CIRCE beamline at ALBA Synchrotron with the collaboration of ALBA staff. F. Oropeza Palacio and Rim C.J. van de Poll are acknowledged for the help with RPES measurements.; esteem3reported; esteem3jra |
Approved |
Most recent IF: 37.8 |
Call Number |
EMAT @ emat @c:irua:192068 |
Serial |
7230 |
Permanent link to this record |