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Author |
de Block, T.; De Baetselier, I.; Van den Bossche, D.; Abdellati, S.; Gestels, Z.; Laumen, J.G.E.; Van Dijck, C.; Vanbaelen, T.; Claes, N.; Vandelannoote, K.; Kenyon, C.; Harrison, O.; Santhini Manoharan-Basil, S. |
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Title |
Genomic oropharyngeal Neisseria surveillance detects MALDI-TOF MS species misidentifications and reveals a novel Neisseria cinerea clade |
Type |
A1 Journal Article |
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Year |
2024 |
Publication |
Journal of Medical Microbiology |
Abbreviated Journal |
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Volume |
73 |
Issue |
8 |
Pages |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Introduction. Commensal Neisseria spp. are highly prevalent in the oropharynx as part of the healthy microbiome. N. meningitidis can colonise the oropharynx too from where it can cause invasive meningococcal disease. To identify N. meningitidis, clinical microbiology laboratories often rely on Matrix Assisted Laser Desorption/Ionisation Time of Flight Mass Spectrometry (MALDI-TOF MS).
Hypothesis/Gap statement. N. meningitidis may be misidentified by MALDI-TOF MS.
Aim. To conduct genomic surveillance of oropharyngeal Neisseria spp. in order to: (i) verify MALDI-TOF MS species identification, and (ii) characterize commensal Neisseria spp. genomes.
Methodology. We analysed whole genome sequence (WGS) data from 119 Neisseria spp. isolates from a surveillance programme for oropharyngeal Neisseria spp. in Belgium. Different species identification methods were compared: (i) MALDI-TOF MS, (ii) Ribosomal Multilocus Sequence Typing (rMLST) and (iii) rplF gene species identification. WGS data were used to further characterize Neisseria species found with supplementary analyses of Neisseria cinerea genomes.
Results. Based on genomic species identification, isolates from the oropharyngeal Neisseria surveilence study were composed of the following species: N. meningitidis (n=23), N. subflava (n=61), N. mucosa (n=15), N. oralis (n=8), N. cinerea (n=5), N. elongata (n=3), N. lactamica (n=2), N. bacilliformis (n=1) and N. polysaccharea (n=1). Of these 119 isolates, four isolates identified as N. meningitidis (n=3) and N. subflava (n=1) by MALDI-TOF MS, were determined to be N. polysaccharea (n=1), N. cinerea (n=2) and N. mucosa (n=1) by rMLST. Phylogenetic analyses revealed that N. cinerea isolates from the general population (n=3, cluster one) were distinct from those obtained from men who have sex with men (MSM, n=2, cluster two). The latter contained genomes misidentified as N. meningitidis using MALDI-TOF MS. These two N. cinerea clusters persisted after the inclusion of published N. cinerea WGS (n=42). Both N. cinerea clusters were further defined through pangenome and Average Nucleotide Identity (ANI) analyses.
Conclusion. This study provides insights into the importance of genomic genus-wide Neisseria surveillance studies to improve the characterization and identification of the Neisseria genus. |
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Publication Date |
2024-08-30 |
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Edition |
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ISSN |
0022-2615 |
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Additional Links |
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Impact Factor |
3 |
Times cited |
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Open Access |
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Notes |
We would like to thank all the study participants for their help in this study. This research was supported by SOFI 2021 grant—‘PReventing the Emergence of untreatable STIs via radical Prevention’ (PRESTIP). |
Approved |
Most recent IF: 3; 2024 IF: 2.159 |
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Call Number |
EMAT @ emat @ |
Serial |
9262 |
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Permanent link to this record |
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Author |
De Beule, C.; Saniz, R.; Partoens, B. |
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Title |
Crystalline topological states at a topological insulator junction |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
The journal of physics and chemistry of solids |
Abbreviated Journal |
J Phys Chem Solids |
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Volume |
128 |
Issue |
128 |
Pages |
144-151 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We consider an interface between two strong time-reversal invariant topological insulators having surface states with opposite spin chirality, or equivalently, opposite mirror Chern number. We show that such an interface supports gapless modes that are protected by mirror symmetry. The interface states are investigated with a continuum model for the Bi2Se3 class of topological insulators that takes into account terms up to third order in the crystal momentum, which ensures that the model has the correct symmetry. The model parameters are obtained from ab initio calculations. Finally, we consider the effect of rotational mismatch at the interface, which breaks the mirror symmetry and opens a gap in the interface spectrum. |
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Wos |
000472693100013 |
Publication Date |
2018-01-31 |
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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 |
0022-3697 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
2.059 |
Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.059 |
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Call Number |
UA @ admin @ c:irua:161391 |
Serial |
5385 |
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Permanent link to this record |
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Author |
De Backer, A.; Zhang, Z.; van den Bos, K.H.W.; Bladt, E.; Sánchez‐Iglesias, A.; Liz‐Marzán, L.M.; Nellist, P.D.; Bals, S.; Van Aert, S. |
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Title |
Element Specific Atom Counting at the Atomic Scale by Combining High Angle Annular Dark Field Scanning Transmission Electron Microscopy and Energy Dispersive X‐ray Spectroscopy |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Small methods |
Abbreviated Journal |
Small Methods |
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Volume |
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Issue |
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Pages |
2200875 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
A new methodology is presented to count the number of atoms in multimetallic nanocrystals by combining energy dispersive X-ray spectroscopy (EDX) and high angle annular dark field scanning transmission electron microscopy (HAADF STEM). For this purpose, the existence of a linear relationship between the incoherent HAADF STEM and EDX images is exploited. Next to the number of atoms for each element in the atomic columns, the method also allows quantification of the error in the obtained number of atoms, which is of importance given the noisy nature of the acquired EDX signals. Using experimental images of an Au@Ag core–shell nanorod, it is demonstrated that 3D structural information can be extracted at the atomic scale. Furthermore, simulated data of an Au@Pt core–shell nanorod show the prospect to characterize heterogeneous nanostructures with adjacent atomic numbers. |
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Wos |
000862072700001 |
Publication Date |
2022-09-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2366-9608 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.4 |
Times cited |
5 |
Open Access |
OpenAccess |
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Notes |
This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S.V.A., Grant 815128 REALNANO to S.B., and Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0267.18N, G.0502.18N, G.0346.21N) and a postdoctoral grant to A.D.B.; esteem3reported; esteem3JRA |
Approved |
Most recent IF: 12.4 |
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Call Number |
EMAT @ emat @c:irua:191570 |
Serial |
7109 |
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Permanent link to this record |
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Author |
De Backer, A.; van den Bos, K.H.W.; Van den Broek, W.; Sijbers, J.; Van Aert, S. |
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Title |
StatSTEM: An efficient approach for accurate and precise model-based quantification of atomic resolution electron microscopy images |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
171 |
Issue |
171 |
Pages |
104-116 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, has been investigated. The highest attainable precision is reached even for low dose images. Furthermore, the advantages of the model-based approach taking into account overlap between neighbouring columns are highlighted. This is done for the estimation of the distance between two neighbouring columns as a function of their distance and for the estimation of the scattering cross-section which is compared to the integrated intensity from a Voronoi cell. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
000389106200014 |
Publication Date |
2016-09-09 |
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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 |
0304-3991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
43 |
Open Access |
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Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0393.11, G.0064.10 and G.0374.13), a Ph.D. research grant to K.H.W. van den Bos, and a postdoctoral research grant to A. De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3). A. Rosenauer is acknowledged for providing the STEMsim program.; esteem2_jra2 |
Approved |
Most recent IF: 2.843 |
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Call Number |
EMAT @ emat @ c:irua:135516 |
Serial |
4280 |
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Permanent link to this record |
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Author |
De Backer, A.; van den Bos, K.H.W.; Van den Broek, W.; Sijbers, J.; Van Aert, S. |
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Title |
StatSTEM: An efficient program for accurate and precise model-based quantification of atomic resolution electron microscopy images |
Type |
P1 Proceeding |
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Year |
2017 |
Publication |
Journal of physics : conference series
T2 – Electron Microscopy and Analysis Group Conference 2017 (EMAG2017), 3-6 July 2017, Manchester, UK |
Abbreviated Journal |
J. Phys.: Conf. Ser. |
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Volume |
902 |
Issue |
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Pages |
012013 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
An efficient model-based estimation algorithm is introduced in order to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for the overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, is investigated. The highest attainable precision is reached even for low dose images. Furthermore, advantages of the model- based approach taking into account overlap between neighbouring columns are highlighted. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
000416370700013 |
Publication Date |
2017-10-16 |
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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 |
1742-6588 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
The authors acknowledge nancial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0374.13N, G.0368.15N, G.0369.15N, WO.010.16N) and a PhD research grant to K H W van den Bos, and a postdoctoral research grant to A De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3). A Rosenauer is acknowledged for providing the STEMsim program. |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @c:irua:147188 |
Serial |
4764 |
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Permanent link to this record |
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Author |
de Backer, A.; Van Aert, S.; van Dyck, D. |
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Title |
High precision measurements of atom column positions using model-based exit wave reconstruction |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
111 |
Issue |
9/10 |
Pages |
1475-1482 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
In this paper, it has been investigated how to measure atom column positions as accurately and precisely as possible using a focal series of images. In theory, it is expected that the precision would considerably improve using a maximum likelihood estimator based on the full series of focal images. As such, the theoretical lower bound on the variances of the unknown atom column positions can be attained. However, this approach is numerically demanding. Therefore, maximum likelihood estimation has been compared with the results obtained by fitting a model to a reconstructed exit wave rather than to the full series of focal images. Hence, a real space model-based exit wave reconstruction technique based on the channelling theory is introduced. Simulations show that the reconstructed complex exit wave contains the same amount of information concerning the atom column positions as the full series of focal images. Only for thin samples, which act as weak phase objects, this information can be retrieved from the phase of the reconstructed complex exit wave. |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000300461200004 |
Publication Date |
2011-07-28 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
8 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
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Call Number |
UA @ lucian @ c:irua:91879 |
Serial |
1438 |
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Permanent link to this record |
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Author |
De Backer, A.; Van Aert, S.; Faes, C.; Arslan Irmak, E.; Nellist, P.D.; Jones, L. |
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Title |
Experimental reconstructions of 3D atomic structures from electron microscopy images using a Bayesian genetic algorithm |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
N P J Computational Materials |
Abbreviated Journal |
npj Comput Mater |
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Volume |
8 |
Issue |
1 |
Pages |
216 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We introduce a Bayesian genetic algorithm for reconstructing atomic models of monotype crystalline nanoparticles from a single projection using Z-contrast imaging. The number of atoms in a projected atomic column obtained from annular dark field scanning transmission electron microscopy images serves as an input for the initial three-dimensional model. The algorithm minimizes the energy of the structure while utilizing a priori information about the finite precision of the atom-counting results and neighbor-mass relations. The results show promising prospects for obtaining reliable reconstructions of beam-sensitive nanoparticles during dynamical processes from images acquired with sufficiently low incident electron doses. |
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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 |
000866500900001 |
Publication Date |
2022-10-12 |
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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 |
2057-3960 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
OpenAccess |
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Notes |
This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S.V.A. and Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0267.18N, G.0502.18N, G.0346.21N) and a postdoctoral grant to A.D.B. L.J. acknowledges Science Foundation Ireland (SFI – grant number URF/RI/191637), the Royal Society, and the AMBER Centre. The authors acknowledge Aakash Varambhia for his assistance and expertise with the experimental recording and use of characterization facilities within the David Cockayne Centre for Electron Microscopy, Department of Materials, University of Oxford, and in particular the EPSRC (EP/K040375/1 South of England Analytical Electron Microscope).; esteem3reported; esteem3JRA |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @c:irua:191398 |
Serial |
7114 |
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Permanent link to this record |
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Author |
de Backer, A.; Martinez, G.T.; Rosenauer, A.; Van Aert, S. |
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Title |
Atom counting in HAADF STEM using a statistical model-based approach : methodology, possibilities, and inherent limitations |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
134 |
Issue |
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Pages |
23-33 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In the present paper, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. In order to count the number of atoms, it is assumed that the total scattered intensity scales with the number of atoms per atom column. These intensities are quantitatively determined using model-based statistical parameter estimation theory. The distribution describing the probability that intensity values are generated by atomic columns containing a specific number of atoms is inferred on the basis of the experimental scattered intensities. Finally, the number of atoms per atom column is quantified using this estimated probability distribution. The number of atom columns available in the observed STEM image, the number of components in the estimated probability distribution, the width of the components of the probability distribution, and the typical shape of a criterion to assess the number of components in the probability distribution directly affect the accuracy and precision with which the number of atoms in a particular atom column can be estimated. It is shown that single atom sensitivity is feasible taking the latter aspects into consideration. |
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Corporate Author |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000324474900005 |
Publication Date |
2013-05-17 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
48 |
Open Access |
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Notes |
FWO; Esteem2; FP 2007-2013; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
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Call Number |
UA @ lucian @ c:irua:109916 |
Serial |
162 |
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Permanent link to this record |
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Author |
de Backer, A.; Martinez, G.T.; MacArthur, K.E.; Jones, L.; Béché, A.; Nellist, P.D.; Van Aert, S. |
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Title |
Dose limited reliability of quantitative annular dark field scanning transmission electron microscopy for nano-particle atom-counting |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
151 |
Issue |
151 |
Pages |
56-61 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Quantitative annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique to characterise nano-particles on an atomic scale. Because of their limited size and beam sensitivity, the atomic structure of such particles may become extremely challenging to determine. Therefore keeping the incoming electron dose to a minimum is important. However, this may reduce the reliability of quantitative ADF STEM which will here be demonstrated for nano-particle atom-counting. Based on experimental ADF STEM images of a real industrial catalyst, we discuss the limits for counting the number of atoms in a projected atomic column with single atom sensitivity. We diagnose these limits by combining a thorough statistical method and detailed image simulations. |
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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 |
000351237800008 |
Publication Date |
2014-12-03 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
29 |
Open Access |
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Notes |
312483 Esteem2; 278510 Vortex; Fwo G039311; G006410; G037413; esteem2ta; ECASJO; |
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
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Call Number |
c:irua:123927 c:irua:123927 |
Serial |
753 |
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Permanent link to this record |
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Author |
De Backer, A.; Jones, L.; Lobato, I.; Altantzis, T.; Goris, B.; Nellist, P.D.; Bals, S.; Van Aert, S. |
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Title |
Three-dimensional atomic models from a single projection using Z-contrast imaging: verification by electron tomography and opportunities |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
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Volume |
9 |
Issue |
9 |
Pages |
8791-8798 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In order to fully exploit structure–property relations of nanomaterials, three-dimensional (3D) characterization at the atomic scale is often required. In recent years, the resolution of electron tomography has reached the atomic scale. However, such tomography typically requires several projection images demanding substantial electron dose. A newly developed alternative circumvents this by counting the number of atoms across a single projection. These atom counts can be used to create an initial atomic model with which an energy minimization can be applied to obtain a relaxed 3D reconstruction of the nanoparticle. Here, we compare, at the atomic scale, this single projection reconstruction approach with tomography and find an excellent agreement. This new approach allows for the characterization of beam-sensitive materials or where the acquisition of a tilt series is impossible. As an example, the utility is illustrated by the 3D atomic scale characterization of a nanodumbbell on an in situ heating holder of limited tilt range. |
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Place of Publication |
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Language |
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Wos |
000404614700031 |
Publication Date |
2017-06-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
|
|
ISSN |
2040-3364 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
7.367 |
Times cited |
33 |
Open Access |
OpenAccess |
|
|
Notes |
The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N, G.0368.15N, and WO.010.16N) and postdoctoral grants to T. Altantzis, A. De Backer, and B. Goris. S. Bals acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078). Funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiatieve-I3) is acknowledged. The authors would also like to thank Luis Liz-Marzán, Marek Grzelczak, and Ana Sánchez-Iglesias for sample provision. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; |
Approved |
Most recent IF: 7.367 |
|
|
Call Number |
EMAT @ emat @ c:irua:144436UA @ admin @ c:irua:144436 |
Serial |
4617 |
|
Permanent link to this record |
|
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Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
|
Title |
Atom counting |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
91-144 |
|
|
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
In this chapter, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high-resolution annular dark-field (ADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. We show that this method can be applied to nanocrystals of arbitrary shape, size, and atom type. The validity of the atom-counting results is confirmed by means of detailed image simulations and it is shown that the high sensitivity of our method enables us to count atoms with single atom sensitivity. |
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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 |
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Publication Date |
2021-03-06 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
|
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
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|
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ admin @ c:irua:177529 |
Serial |
6776 |
|
Permanent link to this record |
|
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|
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Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
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|
Title |
Efficient fitting algorithm |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
73-90 |
|
|
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT) |
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|
Abstract |
An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic-resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighboring columns, enabling the analysis of a large field of view. To provide end-users with this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. In this chapter, this efficient algorithm is applied to three different nanostructures for which the analysis of a large field of view is required. |
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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 |
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Publication Date |
2021-03-06 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
|
Series Volume |
217 |
Series Issue |
|
Edition |
|
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|
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
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|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ admin @ c:irua:177528 |
Serial |
6778 |
|
Permanent link to this record |
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Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
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|
Title |
General conclusions and future perspectives |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
243-253 |
|
|
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
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|
Abstract |
This chapter provides an overview of statistical and quantitative methodologies that have pushed (scanning) transmission electron microscopy ((S)TEM) toward accurate and precise measurements of unknown structure parameters for understanding the relation between the structure of a material and its properties. Hereby, statistical parameter estimation theory has extensively been used which enabled not only measuring atomic column positions, but also quantifying the number of atoms, and detecting atomic columns as accurately and precisely as possible from experimental images. As a general conclusion, it can be stated that advanced statistical techniques are ideal tools to perform quantitative electron microscopy at the atomic scale. In the future, statistical methods will continue to be developed and novel quantification procedures will open up new possibilities for studying material structures at the atomic scale. |
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Corporate Author |
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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 |
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Publication Date |
2021-03-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
217 |
Series Issue |
|
Edition |
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|
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ admin @ c:irua:177533 |
Serial |
6781 |
|
Permanent link to this record |
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|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
|
Title |
Introduction |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
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|
Volume |
|
Issue |
|
Pages |
1-28 |
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Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT) |
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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 |
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Editor |
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Language |
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Wos |
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Publication Date |
2021-03-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
217 |
Series Issue |
|
Edition |
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ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ admin @ c:irua:177525 |
Serial |
6784 |
|
Permanent link to this record |
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|
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
|
Title |
Optimal experiment design for nanoparticle atom counting from ADF STEM images |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
145-175 |
|
|
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
|
Abstract |
In this chapter, the principles of detection theory are used to quantify the probability of error for atom counting from high-resolution scanning transmission electron microscopy (HRSTEM) images. Binary and multiple hypothesis testing have been investigated in order to determine the limits to the precision with which the number of atoms in a projected atomic column can be estimated. The probability of error has been calculated when using STEM images, scattering cross-sections or peak intensities as a criterion to count atoms. Based on this analysis, we conclude that scattering cross-sections perform almost equally well as images and perform better than peak intensities. Furthermore, the optimal STEM detector design can be derived for atom counting using the expression of the probability of error. We show that for very thin objects the low-angle annular dark-field (LAADF) regime is optimal and that for thicker objects the optimal inner detector angle increases. |
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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 |
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Publication Date |
2021-03-06 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
|
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Series Volume |
217 |
Series Issue |
|
Edition |
|
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|
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
|
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ admin @ c:irua:177530 |
Serial |
6785 |
|
Permanent link to this record |
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Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
|
Title |
Statistical parameter estimation theory : principles and simulation studies |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
29-72 |
|
|
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
In this chapter, the principles of statistical parameter estimation theory for a quantitative analysis of atomic-resolution electron microscopy images are introduced. Within this framework, electron microscopy images are described by a parametric statistical model. Here, parametric models are introduced for different types of electron microscopy images: reconstructed exit waves, annular dark-field (ADF) scanning transmission electron microscopy (STEM) images, and simultaneously acquired ADF and annular bright-field (ABF) STEM images. Furthermore, the Cramér-Rao lower bound (CRLB) is introduced, i.e. a theoretical lower bound on the variance of any unbiased estimator. This CRLB is used to quantify the precision of the structure parameters of interest, such as the atomic column positions and the integrated atomic column intensities. |
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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 |
|
Publication Date |
2021-03-06 |
|
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
|
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
|
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ admin @ c:irua:177527 |
Serial |
6788 |
|
Permanent link to this record |
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Author |
de Backer, A.; De wael, A.; Gonnissen, J.; Van Aert, S. |
|
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Title |
Optimal experimental design for nano-particle atom-counting from high-resolution STEM images |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
151 |
Issue |
151 |
Pages |
46-55 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
In the present paper, the principles of detection theory are used to quantify the probability of error for atom-counting from high resolution scanning transmission electron microscopy (HR STEM) images. Binary and multiple hypothesis testing have been investigated in order to determine the limits to the precision with which the number of atoms in a projected atomic column can be estimated. The probability of error has been calculated when using STEM images, scattering cross-sections or peak intensities as a criterion to count atoms. Based on this analysis, we conclude that scattering cross-sections perform almost equally well as images and perform better than peak intensities. Furthermore, the optimal STEM detector design can be derived for atom-counting using the expression for the probability of error. We show that for very thin objects LAADF is optimal and that for thicker objects the optimal inner detector angle increases. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
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Language |
|
Wos |
000351237800007 |
Publication Date |
2014-11-11 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
24 |
Open Access |
|
|
|
Notes |
312483 Esteem2; Fwo G039311; G037413; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
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Call Number |
c:irua:123926 c:irua:123926 |
Serial |
2481 |
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Permanent link to this record |
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Author |
De Backer, A.; De Wael, A.; Gonnissen, J.; Martinez, G.T.; Béché, A.; MacArthur, K.E.; Jones, L.; Nellist, P.D.; Van Aert, S. |
|
|
Title |
Quantitative annular dark field scanning transmission electron microscopy for nanoparticle atom-counting: What are the limits? |
Type |
P1 Proceeding |
|
Year |
2015 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
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|
Volume |
644 |
Issue |
644 |
Pages |
012034 |
|
|
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Quantitative atomic resolution annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique for nanoparticle atom-counting. However, a lot of nanoparticles provide a severe characterisation challenge because of their limited size and beam sensitivity. Therefore, quantitative ADF STEM may greatly benefit from statistical detection theory in order to optimise the instrumental microscope settings such that the incoming electron dose can be kept as low as possible whilst still retaining single-atom precision. The principles of detection theory are used to quantify the probability of error for atom-counting. This enables us to decide between different image performance measures and to optimise the experimental detector settings for atom-counting in ADF STEM in an objective manner. To demonstrate this, ADF STEM imaging of an industrial catalyst has been conducted using the near-optimal detector settings. For this experiment, we discussed the limits for atom-counting diagnosed by combining a thorough statistical method and detailed image simulations. |
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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 |
000366826200034 |
Publication Date |
2015-10-13 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
Electron Microscopy and Analysis Group Conference (EMAG), JUN 02-JUL 02, 2015, Manchester, ENGLAND |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1742-6588 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
|
Impact Factor |
|
Times cited |
|
Open Access |
|
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|
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0368.15N, G.0369.15N, and G.0374.15N) and a PhD research grant to A De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3), ERC Starting Grant 278510 Vortex, and the UK Engineering and Physical Sciences Research Council (EP/K032518/1). The authors acknowledge Johnson-Matthey for providing the sample and PhD funding to K E MacArthur. A Rosenauer is acknowledged for providing the STEMsim program.; esteem2jra2; ECASJO; |
Approved |
Most recent IF: NA |
|
|
Call Number |
c:irua:130314 c:irua:130314 |
Serial |
4050 |
|
Permanent link to this record |
|
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|
|
Author |
de Backer, A.; De wael, A.; Gonnissen, J.; Martinez, G.T.; Béché, A.; MacArthur, K.E.; Jones, L.; Nellist, P.D.; Van Aert, S. |
|
|
Title |
Quantitative annular dark field scanning transmission electron microscopy for nanoparticle atom-counting : what are the limits? |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
|
Volume |
644 |
Issue |
|
Pages |
012034-4 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Quantitative atomic resolution annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique for nanoparticle atom-counting. However, a lot of nanoparticles provide a severe characterisation challenge because of their limited size and beam sensitivity. Therefore, quantitative ADF STEM may greatly benefit from statistical detection theory in order to optimise the instrumental microscope settings such that the incoming electron dose can be kept as low as possible whilst still retaining single-atom precision. The principles of detection theory are used to quantify the probability of error for atom-counting. This enables us to decide between different image performance measures and to optimise the experimental detector settings for atom-counting in ADF STEM in an objective manner. To demonstrate this, ADF STEM imaging of an industrial catalyst has been conducted using the near-optimal detector settings. For this experiment, we discussed the limits for atomcounting diagnosed by combining a thorough statistical method and detailed image simulations. |
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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 |
Bristol |
Editor |
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Language |
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Wos |
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Publication Date |
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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 |
1742-6588; 1742-6596 |
ISBN |
|
Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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|
Notes |
|
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:129198 |
Serial |
4506 |
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Permanent link to this record |
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Author |
De Backer, A.; Bals, S.; Van Aert, S. |
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Title |
A decade of atom-counting in STEM: From the first results toward reliable 3D atomic models from a single projection |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
|
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Volume |
|
Issue |
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Pages |
113702 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Quantitative structure determination is needed in order to study and understand nanomaterials at the atomic scale. Materials characterisation resulting in precise structural information is a crucial point to understand the structure–property relation of materials. Counting the number of atoms and retrieving the 3D atomic structure of nanoparticles plays an important role here. In this paper, an overview will be given of the atom-counting methodology and its applications over the past decade. The procedure to count the number of atoms will be discussed in detail and it will be shown how the performance of the method can be further improved. Furthermore, advances toward mixed element nanostructures, 3D atomic modelling based on the atom-counting results, and quantifying the nanoparticle dynamics will be highlighted. |
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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 |
000953765800001 |
Publication Date |
2023-02-10 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.2 |
Times cited |
3 |
Open Access |
OpenAccess |
|
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Notes |
This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert, Grant 815128 REALNANO to S. Bals, and Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0267.18N, G.0502.18N, G.0346.21N, and EOS 30489208) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF) . The authors also thank the colleagues who have contributed to this work over the years, including T. Altantzis, E. Arslan Irmak, K.J. Batenburg, E. Bladt, A. De wael, R. Erni, C. Faes, B. Goris, L. Jones, L.M. Liz-Marzán, I. Lobato, G.T. Martinez, P.D. Nellist, M.D. Rosell, A. Rosenauer, K.H.W. van den Bos, A. Varambhia, and Z. Zhang.; esteem3reported; esteem3JRA |
Approved |
Most recent IF: 2.2; 2023 IF: 2.843 |
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|
Call Number |
EMAT @ emat @c:irua:195896 |
Serial |
7236 |
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Permanent link to this record |
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Author |
de Backer, A. |
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Title |
Quantitative atomic resolution electron microscopy using advanced statistical techniques |
Type |
Doctoral thesis |
|
Year |
2015 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
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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 |
Antwerpen |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
|
Open Access |
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|
Notes |
|
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:125636 |
Serial |
2747 |
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Permanent link to this record |
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Author |
Das, S.; Rata, A.D.; Maznichenko, I., V; Agrestini, I.S.; Pippel, E.; Gauquelin, N.; Verbeeck, J.; Chen, K.; Valvidares, S.M.; Vasili, H.B.; Herrero-Martin, J.; Pellegrin, E.; Nenkov, K.; Herklotz, A.; Ernst, A.; Mertig, I.; Hu, Z.; Doerr, K. |
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Title |
Low-field switching of noncollinear spin texture at La0.7Sr0.3MnO3-SrRuO3interfaces |
Type |
A1 Journal article |
|
Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
99 |
Issue |
2 |
Pages |
024416 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Interfaces of ferroic oxides can show complex magnetic textures which have strong impact on spintronics devices. This has been demonstrated recently for interfaces with insulating antiferromagnets such as BiFeO3. Here, noncollinear spin textures which can be switched in very low magnetic field are reported for conducting ferromagnetic bilayers of La0.7Sr0.3MnO3-SrRuO3 (LSMO-SRO). The magnetic order and switching are fundamentally different for bilayers coherently grown in reversed stacking sequence. The SRO top layer forms a persistent exchange spring which is antiferromagnetically coupled to LSMO and drives switching in low fields of a few milliteslas. Density functional theory reveals the crucial impact of the interface termination on the strength of Mn-Ru exchange coupling across the interface. The observation of an exchange spring agrees with ultrastrong coupling for the MnO2/SrO termination. Our results demonstrate low-field switching of noncollinear spin textures at an interface between conducting oxides, opening a pathway for manipulating and utilizing electron transport phenomena in controlled spin textures at oxide interfaces. |
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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 |
000455821400005 |
Publication Date |
2019-01-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
3.836 |
Times cited |
19 |
Open Access |
OpenAccess |
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|
Notes |
; The research in Halle was supported by Deutsche Forschungsgemeinschaft (DFG), SFB 762 Functional Oxide Interfaces (Projects No. A9 and No. B1). K.C. benefited from support of the DFG (Project 600575). Discussions with M. Trassin, M. Ziese, H. M. Christen, E.-J. Guo, F. Grcondciel, M. Bibes, and H. N. Lee are gratefully acknowledged. N. G. and J. V. acknowledge funding under the GOA project “Solarpaint” of the University of Antwerp. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. ; |
Approved |
Most recent IF: 3.836 |
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|
Call Number |
UA @ admin @ c:irua:156717 |
Serial |
5255 |
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Permanent link to this record |
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Author |
Das, P.P.; Guzzinati, G.; Coll, C.; Gomez Perez, A.; Nicolopoulos, S.; Estrade, S.; Peiro, F.; Verbeeck, J.; Zompra, A.A.; Galanis, A.S. |
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Title |
Reliable Characterization of Organic & Pharmaceutical Compounds with High Resolution Monochromated EEL Spectroscopy |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Polymers |
Abbreviated Journal |
Polymers-Basel |
|
|
Volume |
12 |
Issue |
7 |
Pages |
1434 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Organic and biological compounds (especially those related to the pharmaceutical industry) have always been of great interest for researchers due to their importance for the development of new drugs to diagnose, cure, treat or prevent disease. As many new API (active pharmaceutical ingredients) and their polymorphs are in nanocrystalline or in amorphous form blended with amorphous polymeric matrix (known as amorphous solid dispersion—ASD), their structural identification and characterization at nm scale with conventional X-Ray/Raman/IR techniques becomes difficult. During any API synthesis/production or in the formulated drug product, impurities must be identified and characterized. Electron energy loss spectroscopy (EELS) at high energy resolution by transmission electron microscope (TEM) is expected to be a promising technique to screen and identify the different (organic) compounds used in a typical pharmaceutical or biological system and to detect any impurities present, if any, during the synthesis or formulation process. In this work, we propose the use of monochromated TEM-EELS, to analyze selected peptides and organic compounds and their polymorphs. In order to validate EELS for fingerprinting (in low loss/optical region) and by further correlation with advanced DFT, simulations were utilized. |
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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 |
000556786700001 |
Publication Date |
2020-06-27 |
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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 |
2073-4360 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.364 |
Times cited |
6 |
Open Access |
OpenAccess |
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Notes |
C.C., F.P., S.E. acknowledges the Spanish government for projects MAT2016-79455-P, Research Network RED2018-102609-T and the FPI (BES-2017-080045) grant of Ministerio de Ciència, Innovación y Universidades. G.G. acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek—Vlaanderen (FWO). P.P.D., A.G.P., S.N. gratefully acknowledge much helpful discussion on EELS study for organic compounds with Dr. Andrey Chuvilin (CIC NANOGUNE, Donostia—San Sebastian, Spain). The authors also acknowledge Raúl Arenal (University de Zaragoza, Spain) for useful discussion on EELS. The authors acknowledge also Ulises Julio Amador Elizondo (Universidad CEU San Pablo, Spain) for kindly provide the aripiprazole and piroxicam samples for EELS study.; EUSMI_TA; |
Approved |
Most recent IF: NA |
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|
Call Number |
EMAT @ emat @c:irua:170603 |
Serial |
6400 |
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Permanent link to this record |
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Author |
Das, P.; Koblischka, M.R.; Turner, S.; Van Tendeloo, G.; Wolf, T.; Jirsa, M.; Hartmann, U. |
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Title |
Direct observation of nanometer-scale pinning sites in (Nd0.33Eu0.20Gd0.47)Ba2Cu3O7-\delta single crystals |
Type |
A1 Journal article |
|
Year |
2008 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
|
|
Volume |
83 |
Issue |
3 |
Pages |
37005,1-37005,4 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the observation of self-organized stripe-like structures on the as-grown surface and in the bulk of (Nd,Eu,Gd)Ba2Cu3Oy single crystals. The periodicity of the stripes on the surface lies between 500800 nm. These are possibly the growth steps of the crystal. Transmission electron microscopy investigations revealed stripes of periodicity in the range of 2040 nm in the bulk. From electron back scattered diffraction investigations, no crystallographic misorientation due to the nanostripes has been found. Scanning tunneling spectroscopic experiments revealed nonsuperconducting regions, running along twin directions, which presumably constitute strong pinning sites. |
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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 |
Paris |
Editor |
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Language |
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Wos |
000259022600032 |
Publication Date |
2008-07-18 |
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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 |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.957 |
Times cited |
5 |
Open Access |
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|
Notes |
|
Approved |
Most recent IF: 1.957; 2008 IF: 2.203 |
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Call Number |
UA @ lucian @ c:irua:76496 |
Serial |
719 |
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Permanent link to this record |
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Author |
Das, A.; Gordon, I.; Wagner, P.; Cannaerts, M.; Moshchalkov, V.V.; Bruynseraede, Y.; Schuddinck, W.; Van Tendeloo, G.; Borghs, G. |
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Title |
Influence of the morphology on the magneto-transport properties of laser-ablated ultrathin La0.7Ba0.3MnO3 films |
Type |
A1 Journal article |
|
Year |
2001 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
90 |
Issue |
3 |
Pages |
1429-1435 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000169868300052 |
Publication Date |
2002-07-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
2 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 2.068; 2001 IF: 2.128 |
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Call Number |
UA @ lucian @ c:irua:54816 |
Serial |
1649 |
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Permanent link to this record |
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Author |
Daniel, P.; Barbey, L.; Groult, D.; Nguyen, N.; Van Tendeloo, G.; Raveau, B. |
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Title |
Mixed valent iron oxides with the 0201-1201 intergrowth structure: (Pb1-xTlx)Sr4Fe2O9 (0≤x≤1) |
Type |
A1 Journal article |
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Year |
1994 |
Publication |
European journal of solid state and inorganic chemistry |
Abbreviated Journal |
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Volume |
31 |
Issue |
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Pages |
235-244 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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 |
Paris |
Editor |
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Language |
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Wos |
A1994NQ48700004 |
Publication Date |
0000-00-00 |
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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 |
0992-4361 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
12 |
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:10030 |
Serial |
2093 |
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Permanent link to this record |
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Author |
Dams, M.; Drijkoningen, L.; Pauwels, B.; Van Tendeloo, G.; de Vos, D.E.; Jacobs, P.A. |
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Title |
Pd-zeolites as heterogeneous catalysts in heck chemistry |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Journal of catalysis |
Abbreviated Journal |
J Catal |
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Volume |
209 |
Issue |
1 |
Pages |
225-236 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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 |
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Language |
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Wos |
000176501100027 |
Publication Date |
2002-10-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9517; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.844 |
Times cited |
157 |
Open Access |
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Notes |
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Approved |
Most recent IF: 6.844; 2002 IF: 3.118 |
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Call Number |
UA @ lucian @ c:irua:54844 |
Serial |
2567 |
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Permanent link to this record |
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Author |
Daems, N.; De Mot, B.; Choukroun, D.; Van Daele, K.; Li, C.; Hubin, A.; Bals, S.; Hereijgers, J.; Breugelmans, T. |
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Title |
Nickel-containing N-doped carbon as effective electrocatalysts for the reduction of CO2 to CO in a continuous-flow electrolyzer |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Sustainable energy & fuels |
Abbreviated Journal |
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Volume |
4 |
Issue |
4 |
Pages |
1296-1311 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
Nickel-containing N-doped carbons were synthesized for the electrochemical reduction of CO2 to CO, which is a promising approach to reduce the atmospheric CO2 levels and its negative impact on the environment. Unfortunately, poor performance (activity, selectivity and/or stability) is still a major hurdle for the economical implementation of this type of materials. The electrocatalysts were prepared through an easily up-scalable and easily tunable method based on the pyrolysis of Ni-containing N-doped carbons. Ni–N–AC–B1 synthesized with a high relative amount of nitrogen and nickel with respect to carbon, was identified as the most promising candidate for this reaction based on its partial CO current density (4.2 mA cm−2), its overpotential (0.57 V) and its faradaic efficiency to CO (>99%). This results in unprecedented values for the current density per g active sites (690 A g−1 active sites). Combined with its decent stability and its high performance in an actual electrolyzer setup, this makes it a promising candidate for the electrochemical reduction of CO2 to CO on a larger scale. Finally, the evaluation of this kind of material in a flow-cell setup has been limited and to the best of our knowledge never included an evaluation of several crucial parameters (e.g. electrolyte type, anode composition and membrane type) and is an essential investigation in the move towards up-scaling and ultimately industrial application of this technique. This study resulted in an optimal cell configuration, consisting of Pt as an anode, Fumatech® as the membrane and 1 M KHCO3 and 2 M KOH as catholyte and anolyte, respectively. In conclusion, this research offers a unique combination of electrocatalyst development and reactor optimization. |
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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 |
000518690900030 |
Publication Date |
2019-12-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
14 |
Open Access |
OpenAccess |
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Notes |
; The authors acknowledge sponsoring from the research foundation of Flanders (FWO) in the frame of a post-doctoral grant (12Y3919N – ND). J. Hereijgers was supported through a postdoctoral fellowship (28761) of the Research Foundation Flanders (FWO). This project was co-funded by the Interreg 2 Seas-Program 2014-2020, co-.nanced by the European Fund for Regional Development in the frame of subsidiary contract nr 2S03-019. This work was further performed in the framework of the Catalisti cluster SBO project CO2PERATE (“All renewable CCU based on formic acid integrated in an industrial microgrid”), with the.nancial support of VLAIO (Flemish Agency for Innovation and Entrepreneurship). This project.nally received funding from the European Research Council (ERC Consolidator Grant 815128, REALNANO). We thank Karen Leyssens for helping with the N<INF>2</INF> physisorption measurements and Kitty Baert (VUB) for analyzing the samples with XPS and Raman. ; sygma |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:165482 |
Serial |
6311 |
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Permanent link to this record |
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Author |
Daele, K.V.; Arenas‐Esteban, D.; Choukroun, D.; Hoekx, S.; Rossen, A.; Daems, N.; Pant, D.; Bals, S.; Breugelmans, T. |
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Title |
Enhanced Pomegranate‐Structured SnO2Electrocatalysts for the Electrochemical CO2Reduction to Formate |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
ChemElectroChem |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
Although most state-of-the-art Sn-based electrocatalysts yield promising results in terms of selectivity and catalyst activity, their stability remains insufficient to date. Here, we demonstrate the successful application of the recently developed pomegranate-structured SnO2 (Pom. SnO2) and SnO2@C (Pom. SnO2@C) nanocomposite electrocatalysts for the efficient electrochemical conversion of CO2 to formate. With an initial selectivity of 83 and 86% towards formate and an operating potential of -0.72 V and -0.64 V vs. RHE, respectively, these pomegranate SnO2 electrocatalysts are able to compete with most of the current state-of-the-art Sn-based electrocatalysts in terms of activity and selectivity. Given the importance of electrocatalyst stability, long-term experiments (24 h) were performed and a temporary loss in selectivity for the Pom. SnO2@C electrocatalyst was largely restored to its initial selectivity upon drying and exposure to air. Of all the used (24 h) electrocatalysts, the pomegranate SnO2@C had the highest selectivity over a time period of one hour, reaching an average recovered FE of 85%, while the commercial SnO2 and bare pomegranate SnO2 electrocatalysts reached an average of 79 and 80% FE towards formate, respectively. Furthermore, the pomegranate structure of Pom. SnO2@C was largely preserved due to the presence of the heterogeneous carbon shell, which acts as a protective layer, physically inhibiting particle segregation/pulverisation and agglomeration. |
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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 |
000936694800001 |
Publication Date |
2023-02-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2196-0216 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
4 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
European Regional Development Fund, E2C 2S03-019 ; |
Approved |
Most recent IF: 4; 2023 IF: 4.136 |
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Call Number |
EMAT @ emat @c:irua:195228 |
Serial |
7249 |
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Permanent link to this record |
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Author |
Dadsetani, M.; Titantah, J.T.; Lamoen, D. |
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Title |
Ab initio calculation of the energy-loss near-edge structure of some carbon allotropes: comparison with n-diamond |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Diamond and related materials |
Abbreviated Journal |
Diam Relat Mater |
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Volume |
19 |
Issue |
1 |
Pages |
73-77 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The energy-loss near-edge structure (ELNES) spectra of several carbon allotropes (non-hydrogenated and hydrogenated face-centered cubic (FCC) carbon, rhombohedral carbon, glitter, hexagonite and lonsdaleite) are calculated within the supercell-core-excited density functional theory approach. In particular an experimental ELNES spectrum of new diamond (n-diamond) [Konyashin et al., Diamond Relat. Mater. 10, (2001) 99102] is compared with the ELNES spectra of FCC carbon, rhombohedral carbon and the so-called glitter structure. Our calculations show that the ELNES spectrum considered in that publication cannot be that of FCC carbon. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000274234500013 |
Publication Date |
2009-11-12 |
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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 |
0925-9635; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.561 |
Times cited |
11 |
Open Access |
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|
Notes |
Goa; Esteem 026019 |
Approved |
Most recent IF: 2.561; 2010 IF: 1.825 |
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Call Number |
UA @ lucian @ c:irua:79444 |
Serial |
29 |
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Permanent link to this record |