Records |
Author |
Van Aert, S.; Turner, S.; Delville, R.; Schryvers, D.; Van Tendeloo, G.; Ding, X.; Salje, E.K.H. |
Title |
Functional twin boundaries |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Phase transitions |
Abbreviated Journal |
Phase Transit |
Volume |
86 |
Issue |
11 |
Pages |
1052-1059 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Functional interfaces are at the core of research in the emerging field of domain boundary engineering where polar, conducting, chiral, and other interfaces and twin boundaries have been discovered. Ferroelectricity was found in twin walls of paraelectric CaTiO3. We show that the effect of functional interfaces can be optimized if the number of twin boundaries is increased in densely twinned materials. Such materials can be produced by shear in the ferroelastic phase rather than by rapid quench from the paraelastic phase. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
|
Language |
|
Wos |
000327475900002 |
Publication Date |
2013-01-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0141-1594;1029-0338; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.06 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.06; 2013 IF: 1.044 |
Call Number |
UA @ lucian @ c:irua:107344 |
Serial |
1304 |
Permanent link to this record |
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Author |
Peelaers, H.; Partoens, B.; Peeters, F.M. |
Title |
Electronic and dynamical properties of Si/Ge core-shell nanowires |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
11 |
Pages |
113411-113411,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Full ab initio techniques are applied to study the electronic and dynamical properties of free standing, hydrogen-passivated Si/Ge core-shell nanowires oriented along the [110] direction. All studied wires exhibit a direct band gap and are found to be structurally stable. The different contributions of the core and shell atoms to the phonon spectra are identified. The acoustic phonon velocities and the frequencies of some typical optical modes are compared with those of pure Si and Ge nanowires. These depend either on the concentration or on the type of core material. Optical modes are hardened and longitudinal acoustic velocities are softened with decreasing wire diameter. |
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 |
000282270000001 |
Publication Date |
2010-09-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and NOI-BOF (University of Antwerp). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:85421 |
Serial |
995 |
Permanent link to this record |
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|
|
Author |
Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. |
Title |
Easily doped p-type, low hole effective mass, transparent oxides |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
6 |
Issue |
6 |
Pages |
20446 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
Fulfillment of the promise of transparent electronics has been hindered until now largely by the lack of semiconductors that can be doped p-type in a stable way, and that at the same time present high hole mobility and are highly transparent in the visible spectrum. Here, a high-throughput study based on first-principles methods reveals four oxides, namely X2SeO2, with X = La, Pr, Nd, and Gd, which are unique in that they exhibit excellent characteristics for transparent electronic device applications – i.e., a direct band gap larger than 3.1 eV, an average hole effective mass below the electron rest mass, and good p-type dopability. Furthermore, for La2SeO2 it is explicitly shown that Na impurities substituting La are shallow acceptors in moderate to strong anion-rich growth conditions, with low formation energy, and that they will not be compensated by anion vacancies VO or VSe. |
Address |
EMAT, Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium |
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 |
English |
Wos |
000369568900001 |
Publication Date |
2016-02-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
55 |
Open Access |
|
Notes |
We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13 and of a GOA fund from the University of Antwerp. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government–department EWI. |
Approved |
Most recent IF: 4.259 |
Call Number |
c:irua:131611 |
Serial |
4036 |
Permanent link to this record |
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Author |
Lenaerts, S.; Honoré, M.; Huyberechts, G.; Roggen, J.; Maes, G. |
Title |
In situ infrared and electrical characterization of tin dioxide gas sensors in nitrogen/oxygen mixtures at temperatures up to 720 K |
Type |
A1 Journal article |
Year |
1994 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
|
Volume |
19 |
Issue |
|
Pages |
478-482 |
Keywords |
A1 Journal article |
Abstract |
FT-IR spectroscopy and impedance measurements of tin dioxide sensor materials at working temperatures up to 450 °C in atmospheres with varying O2/N2 ratio are used as an in situ probe to study the interactions at the surface of the semiconducting oxide. Every diminution in the oxygen content above the sample induces a broad IR absorption band (X-band) between 2300700 cm−1 with a few small peaks in the 1400850 cm−1 region of the spectrum superimposed on it. The X-band results from the enchanced electron concentration in the bulk of the tin dioxide domain. The fine structure is due to the absorption of several kinds of surface oxygen species associated vibration modes. The porous tin dioxide consists of domains were the outward shell is depleted of electrons by the formation of adsorbed O− species on oxygen surface sites, SO(O− species. In our proposed model for the impedance data this gives rise to a parallel RpCp circuit for the domain boundary characteristics and to an Rs parameter for the intradomain resistance. The evolution of these IR and impedance spectroscopic effects with temperature and oxygen content is used to set up, to confirm and refine a physicochemical operation model of tin dioxide gas sensor. This model consists of a sensitizing reaction sequence in the presence of oxygen and a gas-detection reaction sequence when a reducing gas is present. Based on this model, the principal disadvantages of this type of gas sensor become clear. Every factor that influences the concentration of SO(O−) species, causes a conductance modification. If we can control and direct the nature, the number and the arrangement of the tin dioxide domains, a directed development and improvement of the sensor characteristics is possible. |
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 |
A1994NN90000040 |
Publication Date |
2002-07-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0925-4005 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:82014 |
Serial |
5962 |
Permanent link to this record |
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|
|
Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Elusive s-f intrasite interactions and double exchange in solids: ferromagnetic versus nonmagnetic ground state |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of experimental and theoretical physics |
Abbreviated Journal |
J Exp Theor Phys+ |
Volume |
109 |
Issue |
2 |
Pages |
286-292 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
From the theory of many-electron states in atoms, we know that there exists a strong Coulomb repulsion, which results in the electronic term structure of atoms and is responsible for Hunds rules. By expanding the Coulomb on-site repulsion into a multipolar series, we derive this interaction and show that it is also present in solids as a correlation effect, which means that the interaction requires a multideterminant version of the Hartree-Fock method. Of particular interest is the case where this interaction couples states of localized ( f) and delocalized ( s) electrons. We show that the interaction is bilinear in the creation/annihilation operators for localized electrons and bilinear in the operators for conduction electrons. To study the coupling, we consider a simple model in the framework of an effective limited configuration interaction method with one localized f-electron and one itinerant s-electron per crystal site. The on-site multipole interaction between the f- and s-electrons is explicitly taken into account. It is shown that depending on the low-lying excitation spectrum imposed by the crystal electric field, the model can lead not only to ferromagnetism but also to a nonmagnetic state. The model is relevant for solids with localized and itinerant electron states. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Woodbury, N.Y. |
Editor |
|
Language |
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Wos |
000270506500014 |
Publication Date |
2009-09-18 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1063-7761;1090-6509; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.196 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.196; 2009 IF: 0.871 |
Call Number |
UA @ lucian @ c:irua:79163 |
Serial |
1027 |
Permanent link to this record |
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|
Author |
Hofer, C.; Mustonen, K.; Skakalova, V.; Pennycook, T.J. |
Title |
Picometer-precision few-tilt ptychotomography of 2D materials |
Type |
A1 Journal article |
Year |
2023 |
Publication |
2D materials |
Abbreviated Journal |
|
Volume |
10 |
Issue |
3 |
Pages |
035029-7 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
From ripples to defects, edges and grain boundaries, the 3D atomic structure of 2D materials is critical to their properties. However the damage inflicted by conventional 3D analysis precludes its use with fragile 2D materials, particularly for the analysis of local defects. Here we dramatically increase the potential for precise local 3D atomic structure analysis of 2D materials, with both greatly improved dose efficiency and sensitivity to light elements. We demonstrate light atoms can now be located in complex 2D materials with picometer precision at doses 30 times lower than previously possible. Moreover we demonstrate this using WS2, in which the light atoms are practically invisible to conventional methods at low doses. The key advance is combining the concept of few tilt tomography with highly dose efficient ptychography in scanning transmission electron microscopy. We further demonstrate the method experimentally with the even more challenging and newly discovered 2D CuI, leveraging a new extremely high temporal resolution camera. |
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 |
001013151600001 |
Publication Date |
2023-06-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.5 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 5.5; 2023 IF: 6.937 |
Call Number |
UA @ admin @ c:irua:197809 |
Serial |
8915 |
Permanent link to this record |
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|
Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
Title |
Superconducting nanowires: interplay of discrete transverse modes with supercurrent |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
2 |
Pages |
024513,1-024513,11 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
From a numerical solution of the Bogoliubov-de Gennes equations, we investigate an interplay of the transverse discrete modes with a longitudinal supercurrent in a metallic cylindrical superconducting nanowire. The superconductor-to-normal transition induced by a longitudinal superflow of electrons is found to occur as a cascade of jumps in the order parameter (supercurrent and superfluid density) as a function of the superfluid velocity for diameters d<1015 nm (for Al parameters) and sufficiently low temperatures T<0.30.4Tc, with Tc the critical temperature. When approaching Tc, the jumps are smoothed into steplike but continuous drops. A similar picture occurs for d>1520 nm. Only when the diameter exceeds 5070 nm the quantum-size cascades are fully washed out, and we arrive at the mesoscopic regime. Below this regime the critical current density jc exhibits the quantum-size oscillations with pronounced resonant enhancements: the smaller the diameter, the more significant is the enhancement. Thickness fluctuations of real samples will smooth out such oscillations into an overall growth of jc with decreasing nanowire diameter. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000268617500092 |
Publication Date |
2009-07-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77949 |
Serial |
3358 |
Permanent link to this record |
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|
|
Author |
Juchtmans, R.; Guzzinati, G.; Verbeeck, J. |
Title |
Extension of Friedel's law to vortex-beam diffraction |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical Review A |
Abbreviated Journal |
Phys Rev A |
Volume |
94 |
Issue |
94 |
Pages |
033858 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Friedel's law states that the modulus of the Fourier transform of real functions is centrosymmetric, while the phase is antisymmetric. As a consequence of this, elastic scattering of plane-wave photons or electrons within the first-order Born-approximation, as well as Fraunhofer diffraction on any aperture, is bound to result in centrosymmetric diffraction patterns. Friedel's law, however, does not apply for vortex beams, and centrosymmetry in general is not present in their diffraction patterns. In this work we extend Friedel's law for vortex beams by showing that the diffraction patterns of vortex beams with opposite topological charge, scattered on the same two-dimensional potential, always are centrosymmetric to one another, regardless of the symmetry of the scattering object. We verify our statement by means of numerical simulations and experimental data. Our research provides deeper understanding in vortex-beam diffraction and can be used to design new experiments to measure the topological charge of vortex beams with diffraction gratings or to study general vortex-beam diffraction. |
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 |
000384374500010 |
Publication Date |
2016-09-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9926 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.925 |
Times cited |
13 |
Open Access |
|
Notes |
The authors acknowledge support from the FWO (Aspirant Fonds Wetenschappelijk Onderzoek – Vlaanderen) and the EU under the Seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2 and ERC Starting Grant No. 278510 VORTEX.; ECASJO_; |
Approved |
Most recent IF: 2.925 |
Call Number |
EMAT @ emat @ c:irua:137200UA @ admin @ c:irua:137200 |
Serial |
4314 |
Permanent link to this record |
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Author |
Berdiyorov, G.R.; Neek-Amal, M.; Peeters, F.M.; van Duin, A.C.T. |
Title |
Stabilized silicene within bilayer graphene : a proposal based on molecular dynamics and density-functional tight-binding calculations |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
89 |
Issue |
2 |
Pages |
024107-6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Freestanding silicene is predicted to display comparable electronic properties as graphene. However, the yet synthesized silicenelike structures have been only realized on different substrates which turned out to exhibit versatile crystallographic structures that are very different from the theoretically predicted buckled phase of freestanding silicene. This calls for a different approach where silicene is stabilized using very weakly interacting surfaces. We propose here a route by using graphene bilayer as a scaffold. The confinement between the flat graphene layers results in a planar clustering of Si atoms with small buckling, which is energetically unfavorable in vacuum. Buckled hexagonal arrangement of Si atoms similar to freestanding silicene is observed for large clusters, which, in contrast to Si atoms on metallic surfaces, is only very weakly van der Waals coupled to the graphene layers. These clusters are found to be stable well above room temperature. Our findings, which are supported by density-functional tight-binding calculations, show that intercalating bilayer graphene with Si is a favorable route to realize silicene. |
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 |
000332226200002 |
Publication Date |
2014-01-24 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
43 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. was supported by the EU-Marie Curie IIF postdoc Fellowship/299855. One of us (F. M. P.) acknowledges discussions with Professor Hongjun Gao. G. R. B acknowledges the support of the King Fahd University of Petroleum and Minerals, Saudi Arabia, under the TPRG131-CS-15 DSR project. A.C.T.vD acknowledges funding from AFOSR Grants No. FA9550-10-1-0563 and No. FA9550-11-1-0158. ; |
Approved |
Most recent IF: 3.836; 2014 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:115829 |
Serial |
3140 |
Permanent link to this record |
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Author |
Xu, P.; Dong, L.; Neek-Amal, M.; Ackerman, M.L.; Yu, J.; Barber, S.D.; Schoelz, J.K.; Qi, D.; Xu, F.; Thibado, P.M.; Peeters, F.M.; |
Title |
Self-organized platinum nanoparticles on freestanding graphene |
Type |
A1 Journal article |
Year |
2014 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
8 |
Issue |
3 |
Pages |
2697-2703 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Freestanding graphene membranes were successfully functionalized with platinum nanoparticles (Pt NPs). High-resolution transmission electron microscopy revealed a homogeneous distribution of single-crystal Pt NPs that tend to exhibit a preferred orientation. Unexpectedly, the NPs were also found to be partially exposed to the vacuum with the top Pt surface raised above the graphene substrate, as deduced from atomic-scale scanning tunneling microscopy images and detailed molecular dynamics simulations. Local strain accumulation during the growth process is thought to be the origin of the NP self-organization. These findings are expected to shape future approaches in developing Pt NP catalysts for fuel cells as well as NP-functionalized graphene-based high-performance electronics. |
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 |
000333539400085 |
Publication Date |
2014-02-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
38 |
Open Access |
|
Notes |
; M.N.A. acknowledges financial support by the EU-Marie Curie IIF postdoc Fellowship/299855. F.M.P. acknowledges financial support by the ESF-EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-VI), and the Methusalem Foundation of the Flemish Government. L.D. acknowledges financial support by the Taishan Overseas Scholar program (tshw20091005), the International Science & Technology Cooperation Program of China (2014DFA60150), the National Natural Science Foundation of China (51172113), the Shandong Natural Science Foundation (JQ201118), the Qingdao Municipal Science and Technology Commission (12-1-4-136-hz), and the National Science Foundation (DMR-0821159). P.M.T. is thankful for the financial support of the Office of Naval Research under Grant No. N00014-10-1-0181 and the National Science Foundation under Grant No. DMR-0855358. ; |
Approved |
Most recent IF: 13.942; 2014 IF: 12.881 |
Call Number |
UA @ lucian @ c:irua:116881 |
Serial |
2978 |
Permanent link to this record |
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Author |
Yang, Z.; Geise, H.J.; Mehbod, M.; Debrue, G.; Visser, J.W.; Sonneveld, E.J.; Van 't dack, L.; Gijbels, R. |
Title |
Conductivity and electron density of undoped model compounds of poly(phenylene vinylene) |
Type |
A1 Journal article |
Year |
1990 |
Publication |
Synthetic metals |
Abbreviated Journal |
Synthetic Met |
Volume |
39 |
Issue |
2 |
Pages |
137-151 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Fourteen derivatives of trans,trans-1,4-bis[2-phenylethenyl]benzene were synthesized by Wittig reactions as model compounds of poly(paraphenylene vinylene). Structure, configurational homogeneity and absence of ionic impurities were controlled by mass spectrometry, infrared and neutron activation analysis, respectively. Crystallographic unit cell parameters were obtained from X-ray powder patterns and measurements of electrical conductivities were performed on undoped samples. The data of four more compounds containing one or more thiophene rings instead of phenyl rings were added from the 3iterature. If NO2 and Cl groups are excluded from the electron count a good linear correlation is found between the logarithm of the conductivity and the non-σ electron density (View the MathML source). The position of the substituents, on the central or on the terminal ring, also plays a role in as much as it affects the molecular volume of the compound but not the non-σ electron density. The correlation between the logarithm of the conductivity and the absorption coefficient of the longest wavelength of UV absorption identifies the π electrons in the chromophore as the principal charge carriers. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
A1990EV12900001 |
Publication Date |
2003-06-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0379-6779; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.252 |
Times cited |
25 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:111483 |
Serial |
481 |
Permanent link to this record |
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|
|
Author |
Ignatova, V.A.; van Vaeck, L.; Gijbels, R.; Adams, F. |
Title |
Capabilities and limitations of Fourier transform laser microprobe mass spectrometry for molecular analysis of solids |
Type |
A1 Journal article |
Year |
2002 |
Publication |
Vacuum |
Abbreviated Journal |
Vacuum |
Volume |
69 |
Issue |
|
Pages |
307-313 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Fourier transform laser microprobe mass spectrometry (FT LMMS) has been developed for the molecular analysis of both organic and inorganic components at the surface of microobjects with the ultimate specificity of high-mass resolution. These capabilities are needed in numerous applications of practical material analysis, such as tracing back anomalies in microobjects. The purpose of this paper is to address representative example from industrial trouble shooting, in which organic and inorganic analytes in a single microparticle have been identified unambiguously. This motivates the research to extend the methodology towards quantification. This paper deals with the fundamental aspect of information depth, specifically for inorganic molecular adduct ions. Finally, data will show the quantitative capabilities of FT LMMS. A suitable methodology for the preparation of reference specimens has allowed the empirical calibration of the response as a function of the local concentration to be achieved. |
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 |
000180739000050 |
Publication Date |
2002-12-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0042-207X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.53 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.53; 2002 IF: 0.723 |
Call Number |
UA @ lucian @ c:irua:43192 |
Serial |
274 |
Permanent link to this record |
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|
|
Author |
Cabal, A.; Schalm, O.; Eyskens, P.; Willems, P.; Harth, A.; van Espen, P. |
Title |
Comparison of x-ray absorption and emission techniques for the investigation of paintings |
Type |
A1 Journal article |
Year |
2015 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
|
Volume |
44 |
Issue |
3 |
Pages |
141-148 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
Abstract |
Four x-ray techniques: computed radiography, emission radiography, energy-resolved radiography and imaging x-ray fluorescence were compared using four mock-up panel paintings. The paintings have different stratigraphy and pigments and are representative for different historical periods. One of the paintings has a hidden underlying painting. The type of pigments used mainly influences the information obtained by both the emission and absorption measurements; high-Z white pigment and high-Z color pigments giving the best contrast. Each of the techniques revealed interesting aspects of the paintings, but none of them could reveal the hidden painting to a satisfactory level. Due to the statistical quality of the spectral data, x-ray fluorescence gives elemental images with high contrast. The radiographic images are better to reveal the internal structure. Imaging x-ray fluorescence and energy-resolved radiography measurements can be done simultaneously, and the combination has the highest potential for the study of complex multilayer paintings. Copyright (c) 2015 John Wiley & Sons, Ltd. |
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 |
000353644500010 |
Publication Date |
2015-02-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:126016 |
Serial |
7698 |
Permanent link to this record |
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|
|
Author |
Jannis, D.; Hofer, C.; Gao, C.; Xie, X.; Béché, A.; Pennycook, Tj.; Verbeeck, J. |
Title |
Event driven 4D STEM acquisition with a Timepix3 detector: Microsecond dwell time and faster scans for high precision and low dose applications |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
233 |
Issue |
|
Pages |
113423 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Four dimensional scanning transmission electron microscopy (4D STEM) records the scattering of electrons in a material in great detail. The benefits offered by 4D STEM are substantial, with the wealth of data it provides facilitating for instance high precision, high electron dose efficiency phase imaging via centre of mass or ptychography based analysis. However the requirement for a 2D image of the scattering to be recorded at each probe position has long placed a severe bottleneck on the speed at which 4D STEM can be performed. Recent advances in camera technology have greatly reduced this bottleneck, with the detection efficiency of direct electron detectors being especially well suited to the technique. However even the fastest frame driven pixelated detectors still significantly limit the scan speed which can be used in 4D STEM, making the resulting data susceptible to drift and hampering its use for low dose beam sensitive applications. Here we report the development of the use of an event driven Timepix3 direct electron camera that allows us to overcome this bottleneck and achieve 4D STEM dwell times down to 100 ns; orders of magnitude faster than what has been possible with frame based readout. We characterize the detector for different acceleration voltages and show that the method is especially well suited for low dose imaging and promises rich datasets without compromising dwell time when compared to conventional STEM imaging. |
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 |
000734396800003 |
Publication Date |
2021-11-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.2 |
Times cited |
31 |
Open Access |
OpenAccess |
Notes |
This project has received funding from the Euro- pean Union’s Horizon 2020 Research Infrastructure – Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3. J.V. and A.B. acknowledge funding from FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’). J.V. and D.J. ac- knowledge funding from FWO project G042920N ‘Co- incident event detection for advanced spectroscopy in transmission electron microscopy’. We acknowledge funding under the European Union’s Horizon 2020 re- search and innovation programme (J.V. and D.J un- der grant agreement No 101017720, FET-Proactive EBEAM, and C.H., C.G., X.X. and T.J.P. from the Eu- ropean Research Council (ERC) Grant agreement No. 802123-HDEM).; esteem3JRA; esteem3reported |
Approved |
Most recent IF: 2.2 |
Call Number |
EMAT @ emat @c:irua:183948 |
Serial |
6828 |
Permanent link to this record |
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|
Author |
Vos, L.; Van Grieken, R. |
Title |
Preparation of conducting electrodes from biological samples for multi-element trace analysis by spark-source mass spectrometry or emission spectrometry |
Type |
A1 Journal article |
Year |
1984 |
Publication |
Analytica chimica acta |
Abbreviated Journal |
|
Volume |
164 |
Issue |
|
Pages |
83-90 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Four decomposition procedures frequently used for biological material (dry ashing, open wet digestion, wet digestion in a teflon bomb and low-temperature ashing) are optimized for the conversion of biological samples to conducting electrodes suitable for multi-element trace determinations by spark-source mass spectrometry or emission spectrometry. The optimized procedures are evaluated with respect to contamination, retention and preconcentration of the trace elements, homogeneity of the electrodes and precision of the final results. Both dry-ashing methods are prone to losses by volatilization; simple dry ashing suffers from contamination problems during electrode preparation. Wet digestion gives better precision; digestion with nitric/sulfuric acids in an open flask is the method of choice for most elements being simpler and giving lower blanks than the bomb method. |
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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 |
A1984ABC2700007 |
Publication Date |
2002-07-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2670; 1873-4324 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:116443 |
Serial |
8411 |
Permanent link to this record |
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|
Author |
Kabsch-Korbutowicz, M.; Krupinska, B. |
Title |
Removal of natural organic matter from water by using ion-exchange resins |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Przemysl chemiczny
T2 – Scientific and Technical Conference on Water and Wastewater Basis for, Environmental Protection (School of Quality Water 2008), MAY 28-30, 2008, Kolobrzeg, POLAND |
Abbreviated Journal |
|
Volume |
87 |
Issue |
5 |
Pages |
473-475 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Four aq. solns. contg. natural peat components and the water from Odra river were treated with 3 anion-exchange resins (2.5 to 15 cm(3) of resin per 1 dm(3) of the sample) for 5-60 min to remove the org. matter. The process efficiency was detd. by UV absorbance (254 nm) and colour intensity measurements. The treatment resulted in discoloration of the solns. A resin with weak alky, was the most efficient. The degree of removal increased with increasing the resin dose and contact time. The presence of inorg. anions in the soins. contributed to a decrease of process effectivity. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000257179000020 |
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 |
|
Edition |
|
ISSN |
0033-2496 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:102617 |
Serial |
8471 |
Permanent link to this record |
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|
Author |
Odin, G.P.; Vanmeert, F.; Farges, F.; Gand, G.; Janssens, K.; Romero-Sarmiento, M.-F.; Steyer, J.S.; Vantelon, D.; Rouchon, V. |
Title |
Alteration of fossil-bearing shale (Autun, France; Permian), part II : monitoring artificial and natural ageing by combined use of S and Ca K-edge XANES analysis, Rock-Eval pyrolysis and FTIR analysis |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Annales de paléontologie |
Abbreviated Journal |
Ann Paleontol |
Volume |
101 |
Issue |
3 |
Pages |
225-239 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Fossil-bearing shale specimens that include sulfides in their compositions are chemically reactive and sometimes also mechanically fragile. This decay is often related to iron sulfate efflorescence resulting from the oxidation of sulfide compounds. The processes underlying these degradations are poorly known, thus impeding the elaboration of curative or preventive treatments. The present contribution aims to identify the origin of museum specimen alterations. It focuses on the Flouest collection housed at the Museum National d'Histoire Naturelle (MNHN, Paris, France) and originating from the Autun Basin (Saone-et-Loire, France, Permian). To evaluate the alteration of MNHN specimens, it appeared necessary to compare their composition with that of unaltered shale so as to identify chemical changes occurring during ageing. Therefore, new material was collected in the Autun Basin, among others on the locality of Muse that corresponds to the same lithostratigraphic unit as that of the MNHN specimens. This material was, if necessary, artificially aged. The first part of this work, presented elsewhere, deals with the use of Xray diffraction and Mossbauer spectroscopy for characterizing iron reactivity and speciation. It leads to the conclusion that the reactivity of iron in the shale matrix was limited and could not account for the large efflorescence of iron (II) sulfate occurring nearby the fossil. The second part presented here focuses on the use of S K-edge X-ray Absorption Near Edge Structure (XANES) spectroscopy for characterizing sulfur speciation and reactivity. Measurements were performed on the shale matrix and on thin layers of maceral found in the proximity of damaged areas. As sulfur may be found in association with calcium or organic matter, complementary techniques were implemented, such as FTIR spectroscopy, Rock-Eval pyrolysis (characterization of organic matter content) and Ca K-edge XANES (analysis of calcium speciation) spectroscopy. It was shown that sulfur is mainly related to thioether, sulfoxide, iron sulfide, and sulfates whereas calcium is mainly bound to carboxylate, carbonate and/or sulfate groups. FTIR analysis of the macerals confirmed the presence of vitrinite on damaged MNHN specimens. The low oxygen content of new shale samples determined by Rock-Eval pyrolysis indicates that the organic matter is well preserved, despite the fact that samples come from outcrop surface. In the newly collected material, sulfur is mainly related to organic sulfides (thioether) with a minor occurrence of iron sulfide. In the shale fraction of damaged MNHN specimens, sulfur is mostly oxidized into a mixture of iron and calcium sulfate. However, in the vitrinite layers of the same specimens, a large proportion of sulfur corresponds to organic sulfides. Also the oxidation of sulfur does not occur homogeneously but preferentially in the shale fraction, probably because this latter is porous whereas vitrinite is not. Artificial ageing of new shale material showed that the oxidation of organic sulfides could be reproduced at 90 degrees C, 80% of relative humidity. However, the obtained efflorescence almost exclusively corresponds to calcium sulfate whereas iron (II) sulfates are mostly observed on MNHN specimens. The new material collected on site is probably to be questioned, and future studies will have to select new samples with fossil remains. This will be the object of the third part of this work. (C) 2015 Elsevier Masson SAS. All rights reserved. |
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 |
000363821700009 |
Publication Date |
2015-05-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0753-3969 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.113 |
Times cited |
6 |
Open Access |
|
Notes |
; This work was conducted within a PhD work that was supported by a doctoral school grant of the Museum national d'Histoire naturelle, Paris, France. We acknowledge SOLEIL for provision of synchrotron radiation facilities (Proposals ID “20130462” and “20110189”) and we would like to thank Nicolas Trcera, Pierre Lagarde and Anne Marie Flanck for assistance in using beamline LUCIA. ; |
Approved |
Most recent IF: 1.113; 2015 IF: 0.970 |
Call Number |
UA @ admin @ c:irua:129523 |
Serial |
5462 |
Permanent link to this record |
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Author |
Ma, X.; Pavlidis, G.; Dillon, E.; Beltran, V.; Schwartz, J.J.; Thoury, M.; Borondics, F.; Sandt, C.; Kjoller, K.; Berrie, B.H.; Centrone, A. |
Title |
Micro to nano : multiscale IR analyses reveal zinc soap heterogeneity in a 19th-century painting by Corot |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Analytical chemistry |
Abbreviated Journal |
|
Volume |
94 |
Issue |
7 |
Pages |
3103-3110 |
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
Formation and aggregation of metal carboxylates (metal soaps) can degrade the appearance and integrity of oil paints, challenging efforts to conserve painted works of art. Endeavors to understand the root cause of metal soap formation have been hampered by the limited spatial resolution of Fourier transform infrared microscopy (mu-FTIR). We overcome this limitation using optical photothermal infrared spectroscopy (O-PTIR) and photothermal-induced resonance (PTIR), two novel methods that provide IR spectra with approximate to 500 and approximate to 10 nm spatial resolutions, respectively. The distribution of chemical phases in thin sections from the top layer of a 19th-century painting is investigated at multiple scales (mu-FTIR approximate to 10(2) mu m(3), O-PTIR approximate to 10(-1) mu m(3), PTIR approximate to 10(-5) mu m(3)). The paint samples analyzed here are found to be mixtures of pigments (cobalt green, lead white), cured oil, and a rich array of intermixed, small (often << 0.1 mu m(3)) zinc soap domains. We identify Zn stearate and Zn oleate crystalline soaps with characteristic narrow IR peaks (approximate to 1530-1558 cm(-1)) and a heterogeneous, disordered, water-permeable, tetrahedral zinc soap phase, with a characteristic broad peak centered at approximate to 1596 cm(-1). We show that the high signal-to-noise ratio and spatial resolution afforded by O-PTIR are ideal for identifying phase-separated (or locally concentrated) species with low average concentration, while PTIR provides an unprecedented nanoscale view of distributions and associations of species in paint. This newly accessible nanocompositional information will advance our knowledge of chemical processes in oil paint and will stimulate new art conservation practices. |
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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 |
000766206700011 |
Publication Date |
2022-02-09 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:187380 |
Serial |
8897 |
Permanent link to this record |
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|
Author |
Van Echelpoel, R.; Kranenburg, R.; van Asten, A.; De Wael, K. |
Title |
Electrochemical detection of MDMA and 2C-B in ecstasy tablets using a selectivity enhancement strategy by in-situ derivatization |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Forensic chemistry |
Abbreviated Journal |
|
Volume |
27 |
Issue |
|
Pages |
100383 |
Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
Forensic drug laboratories are confronted with increasing amounts of drugs and a demand for faster results that are directly available on-site. In addition, the drug market is getting more complex with hundreds of new psychoactive substances (NPS) entering the market in recent years. Rapid and on-scene presumptive drug testing therefore faces a shift from manual colorimetric tests towards approaches that can detect a wider range of components and process results automatically. Electrochemical detection offers these desired characteristics, making it a suitable candidate for on-site drug detection. In this study, a two-step electrochemical sensor is introduced for the detection of MDMA and 2C-B. Firstly, a direct electrochemical analysis was performed to detect MDMA. Validation experiments on over 70 substances revealed that 2C-B was the only frequently encountered drug that gave a false positive result for MDMA in this first analysis. A second step using in-situ derivatization was subsequently introduced. To this end, formaldehyde was used for N-methylation of 2C-B thereby enhancing its electrochemical profile. The enriched electrochemical fingerprint in the second step allowed for clear differentiation between MDMA and 2C-B. The applicability of this approach was demonstrated with 71 ecstasy tablets seized by the Amsterdam Police. The MDMA/2C-B sensor correctly identified all 39 MDMA-containing tablets and 10 out of 11 tablets containing 2C-B. Most notably, correct results were also obtained for dark colored tablets in which both spectroscopic analysis and colorimetric tests failed due to obscured signals. |
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 |
000725708200002 |
Publication Date |
2021-11-23 |
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 |
2468-1709 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.7 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 2.7 |
Call Number |
UA @ admin @ c:irua:183340 |
Serial |
7149 |
Permanent link to this record |
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|
Author |
Vanderborght, B.M.; Van Grieken, R.E. |
Title |
Water analysis by spark-source mass-spectrometry after preconcentration on activated carbon |
Type |
A1 Journal article |
Year |
1980 |
Publication |
Talanta : the international journal of pure and applied analytical chemistry |
Abbreviated Journal |
|
Volume |
27 |
Issue |
5 |
Pages |
417-422 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
For trace analyses of environmental waters, spark-source mass-spectrometry has been combined with a preconcentration procedure involving chelation of the dissolved trace elements with oxine and subsequent adsorption of the oxinates and naturally occurring organic and colloidal metal species onto activated carbon. The activated carbon is filtered off and ashed at low temperature. The residue is dissolved, an internal standard and pure graphite are added and, after drying, the electrodes are prepared. The photographically recorded mass spectrum is evaluated by a suitable computer routine. The error of the procedure is around 30%. While this preconcentration and analysis procedure is capable of measuring about 40 elements quantitatively, in practice 1025 trace elements are determined simultaneously above the 0.1-μg/l. detection limit, as is illustrated by analyses of drinking water, surface and ground water samples. Although a sophisticated technique, SSMS can be considered for regular panoramic survey analyses. |
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 |
A1980JR07800006 |
Publication Date |
2002-07-25 |
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 |
0039-9140; 1873-3573 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:116557 |
Serial |
8746 |
Permanent link to this record |
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Author |
Blommaerts, N.; Vanrompay, H.; Nuti, S.; Lenaerts, S.; Bals, S.; Verbruggen, S.W. |
Title |
Unraveling Structural Information of Turkevich Synthesized Plasmonic Gold-Silver Bimetallic Nanoparticles |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Small |
Abbreviated Journal |
Small |
Volume |
15 |
Issue |
15 |
Pages |
1902791 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
For the synthesis of gold-silver bimetallic nanoparticles, the Turkevich method has been the state-of-the-art method for several decades. It has been presumed that this procedure results in a homogeneous alloy, although this has been debatable for many years. In this work, it is shown that neither a full alloy, nor a perfect core-shell particle is formed but rather a core-shell-like particle with altering metal composition along the radial direction. In-depth wet-chemical experiments are performed in combination with advanced transmission electron microscopy, including EDX tomography, and Finite Element Method modeling to support the observations. From the electron tomography results, the core-shell structure could be clearly visualized and the spatial distribution of gold and silver atoms could be quantified. Theoretical simulations are performed to demonstrate that even though UV-Vis spectra show only one plasmon band, this still originates from core-shell type structures. The simulations also indicate that the core-shell morphology does not so much affect the location of the plasmon band, but mainly results in significant band broadening. Wet-chemistry experiments provide the evidence that the synthesis pathway starts with gold enriched alloy cores, and later on in the synthesis mainly silver is incorporated to end up with a silver enriched alloy shell. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000482637100001 |
Publication Date |
2019-08-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1613-6810 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.643 |
Times cited |
26 |
Open Access |
OpenAccess |
Notes |
Universiteit Antwerpen; Fonds Wetenschappelijk Onderzoek, 1S32617N G.0369.15N G.0381.16N ; |
Approved |
Most recent IF: 8.643 |
Call Number |
EMAT @ emat @c:irua:161636 |
Serial |
5290 |
Permanent link to this record |
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|
Author |
van der Snickt, G.; de Nolf, W.; Vekemans, B.; Janssens, K. |
Title |
μ-XRF/μ-RS vs. SR μ-XRD for pigment identification in illuminated manuscripts |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
Appl Phys A-Mater |
Volume |
92 |
Issue |
1 |
Pages |
59-68 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
For the non-destructive identification of pigments and colorants in works of art, in archaeological and in forensic materials, a wide range of analytical techniques can be used. Bearing in mind that every method holds particular limitations, two complementary spectroscopic techniques, namely confocal ì-Raman spectroscopy (ì-RS) and ì-X-ray fluorescence spectroscopy (ì-XRF), were joined in one instrument. The combined ì-XRF and ì-RS device, called PRAXIS unites both complementary techniques in one mobile setup, which allows ì- and in situ analysis. ì-XRF allows one to collect elemental and spatially-resolved information in a non-destructive way on major and minor constituents of a variety of materials. However, the main disadvantages of ì-XRF are the penetration depth of the X-rays and the fact that only elements and not specific molecular combinations of elements can be detected. As a result ì-XRF is often not specific enough to identify the pigments within complex mixtures. Confocal Raman microscopy (ì-RS) can offer a surplus as molecular information can be obtained from single pigment grains. However, in some cases the presence of a strong fluorescence background limits the applicability. In this paper, the concrete analytical possibilities of the combined PRAXIS device are evaluated by comparing the results on an illuminated sheet of parchment with the analytical information supplied by synchrotron radiation ì-X-ray diffraction (SR ì-XRD), a highly specific technique. |
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 |
|
Language |
|
Wos |
000256426000008 |
Publication Date |
2008-03-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0947-8396 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.455 |
Times cited |
56 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.455; 2008 IF: 1.884 |
Call Number |
UA @ admin @ c:irua:74465 |
Serial |
5695 |
Permanent link to this record |
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|
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Author |
Krata, A.; Kontozova-Deutsch, V.; Bencs, L.; Deutsch, F.; Van Grieken, R. |
Title |
Single-run ion chromatographic separation of inorganic and low-molecular-mass organic anions under isocratic elution: application to environmental samples |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Talanta : the international journal of pure and applied analytical chemistry |
Abbreviated Journal |
|
Volume |
79 |
Issue |
1 |
Pages |
16-21 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
For the isocratic ion chromatography (IC) separation of low-molecular-mass organic acids and inorganic anions three different anion-exchange columns were studied: IonPac AS14 (9 ìm particle size), Allsep A-2 (7 ìm particle size), and IC SI-50 4E (5 ìm particle size). A complete baseline separation for all analyzed anions (i.e., F−, acetate, formate, Cl−, NO2−, Br−, NO3−, HPO42− and SO42−) in one analytical cycle of shorter than 17 min was achieved on the IC SI-50 4E column, using an eluent mixture of 3.2 mM Na2CO3 and 1.0 mM NaHCO3 with a flow rate of 1.0 mL min−1. On the IonPac AS14 column, it was possible to separate acetate from inorganic anions in one run (i.e., less than 9 min), but not formate, under the following conditions: 3.5 mM Na2CO3 plus 1.0 mM NaHCO3 with a flow rate of 1.2 mL min−1. Therefore, it was necessary to adapt a second run with a 2.0 mM Na2B4O7 solution as an eluent under a flow rate of 0.8 mL min−1 for the separation of organic ions, which considerably enlarged the analysis time. For the Allsep A-2 column, using an eluent mixture of 1.2 mM Na2CO3 plus 1.5 mM NaHCO3 with a flow rate of 1.6 mL min−1, it was possible to separate almost all anions in one run within 25 min, except the fluoride-acetate critical pair. A Certified Multianion Standard Solution PRIMUS for IC was used for the validation of the analytical methods. The lowest RSDs (less than 1%) and the best LODs (0.02, 0.2, 0.16, 0.11, 0.06, 0.05, 0.04, 0.14 and 0.09 mg L−1 for F−, Ac−, For−, Cl−, NO2−, Br−, NO3−, HPO42− and SO42−, respectively) were achieved using the IC SI-50 4E column. This column was applied for the separation of concerned ions in environmental precipitation samples such as snow, hail and rainwater. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000266187600004 |
Publication Date |
2009-03-06 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0039-9140; 1873-3573 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:75475 |
Serial |
8542 |
Permanent link to this record |
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|
|
Author |
Sankaran, K.; Swerts, J.; Carpenter, R.; Couet, S.; Garello, K.; Evans, R.F.L.; Rao, S.; Kim, W.; Kundu, S.; Crotti, D.; Kar, G.S.; Pourtois, G. |
Title |
Evidence of magnetostrictive effects on STT-MRAM performance by atomistic and spin modeling |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
2018 Ieee International Electron Devices Meeting (iedm) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
For the first time, we demonstrate, using an atomistic description of a 30nm diameter spin-transfer-torque magnetic random access memories (STT-MRAM), that the difference in mechanical properties of its sub-nanometer layers induces a high compressive strain in the magnetic tunnel junction (MTJ) and leads to a detrimental magnetostrictive effect. Our model explains the issues met in engineering the electrical and magnetic performances in scaled STT-MRAM devices. The resulting high compressive strain built in the stack, particularly in the MgO tunnel barrier (t-MgO), and its associated non-uniform atomic displacements, impacts on the quality of the MTJ interface and leads to strain relieve mechanisms such as surface roughness and adhesion issues. We illustrate that the strain gradient induced by the different materials and their thicknesses in the stacks has a negative impact on the tunnel magneto-resistance (TMR), on the magnetic nucleation process and on the STT-MRAM performance. |
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 |
000459882300147 |
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-72811-987-8; 978-1-72811-987-8 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:158694 |
Serial |
7942 |
Permanent link to this record |
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|
|
Author |
Tan, H.; Lebedev, O.I.; McLaughlin, A.C.; Van Tendeloo, G. |
Title |
The superstructure and superconductivity of Ru1222 based RuSr2Gd2-x-yYyCexCu2O10-\delta compounds |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
23 |
Issue |
11 |
Pages |
115013-115013,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
For the first time, the local structure and physical properties of Ru1222 based compounds (RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta) and RuSr(2)Gd(1.8-x)Y(0.2)CexCu(2)O(10) (x = 0.90-0.55)) have been investigated and analyzed together on the very same compounds. The Ru1222 superstructure was confirmed by TEM at a local scale and was suggested to have an orthorhombic symmetry with space group Aba2 and lattice parameters a(s) similar or equal to root 2a, b(s) similar or equal to root 2a and c(s) = c. This new Ru1222 superstructure distortion from tetragonal symmetry is proposed to have a positive correlation with the superconductivity variation of these compounds. The more the distortion towards orthorhombic symmetry, the higher the critical superconducting temperature these compounds can achieve. The T(c)(0) of RuSr(2)Gd(1.8-x)Y(0.2)Ce(x)Cu(2)O(10-delta) (x = 0.85-0.55) increases monotonically from 4 to 16 K when x decreases from 0.85 to 0.70, then RuSr(2)Gd(2)Cu(2)O(8) defects emerge and the T(c) decreases with decreasing x. Ru1212 defects are observed to intergrow epitaxially with the Ru1222 structure as lamellas along the c-axis in RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta). Although Ru1212 is a superconductor, the intergrowth severely restrains its superconductivity. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000284308000013 |
Publication Date |
2010-10-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
1 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.878; 2010 IF: 2.402 |
Call Number |
UA @ lucian @ c:irua:95553 |
Serial |
3385 |
Permanent link to this record |
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|
|
Author |
Snoeckx, R.; Rabinovich, A.; Dobrynin, D.; Bogaerts, A.; Fridman, A. |
Title |
Plasma-based liquefaction of methane: The road from hydrogen production to direct methane liquefaction |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Plasma processes and polymers |
Abbreviated Journal |
Plasma Process Polym |
Volume |
14 |
Issue |
14 |
Pages |
1600115 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
For the energy industry, a process that is able to transform methane—being the prime component of natural gas—efficiently into a liquid product would be equivalent to a goose with golden eggs. As such it is no surprise that research efforts in this field already date back to the nineteen hundreds. Plasma technology can be considered to be a novel player in this field, but nevertheless one with great potential. Over the past decades this technology has evolved from sole hydrogen production, over indirect methane liquefaction to eventually direct plasma-assisted methane liquefaction processes. An overview of this evolution and these processes is presented, from which it becomes clear that the near future probably lies with the direct two phase plasma-assisted methane liquefaction and the far future with the direct oxidative methane liquefaction. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000403699900008 |
Publication Date |
2016-10-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1612-8850 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.846 |
Times cited |
16 |
Open Access |
Not_Open_Access |
Notes |
Advanced Plasma Solutions; Drexel University; Federaal Wetenschapsbeleid; Fonds De La Recherche Scientifique – FNRS, G038316N V403616N ; |
Approved |
Most recent IF: 2.846 |
Call Number |
PLASMANT @ plasmant @ c:irua:144212 |
Serial |
4622 |
Permanent link to this record |
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|
Author |
Batuk, M.; Buffiere, M.; Zaghi, A.E.; Lenaers, N.; Verbist, C.; Khelifi, S.; Vleugels, J.; Meuris, M.; Hadermann, J. |
Title |
Effect of the burn-out step on the microstructure of the solution-processed Cu(In,Ga)Se2 solar cells |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
583 |
Issue |
583 |
Pages |
142-150 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
For the development of the photovoltaic industry cheap methods for the synthesis of Cu(In,Ga)Se-2 (CIGSe) based solar cells are required. In this work, CIGSe thin films were obtained by a solution-based method using oxygen-bearing derivatives. With the aimof improving the morphology of the printed CIGSe layers, we investigated two different annealing conditions of the precursor layer, consisting of (1) a direct selenization step (reference process), and (2) a pre-treatment thermal step prior to the selenization. We showed that the use of an Air/H2S burn-out step prior to the selenization step increases the CIGSe grain size and reduces the carbon content. However, it leads to the reduction of the solar cell efficiency from 4.5% in the reference sample down to 0.5% in the annealed sample. Detailed transmission electron microscopy analysis, including high angle annular dark field scanning transmission electron microscopy and energy dispersive X-ray mapping, was applied to characterize the microstructure of the film and to determine the relationship between microstructure and the solar cell performance. We demonstrated that the relatively low efficiency of the reference solar cells is related not only to the nanosize of the CIGSe grains and presence of the pores in the CIGSe layer, but also to the high amount of secondary phases, namely, In/Ga oxide (or hydroxide) amorphous matter, residuals of organicmatter (carbon), and copper sulfide that is formed at the CIGSe/MoSe2 interface. The annealing in H2S during the burn-out step leads to the formation of the copper sulfide at all grain boundaries and surfaces in the CIGSe layer, which results in the noticeably efficiency drop. (C) 2015 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
|
Language |
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Wos |
000353812400024 |
Publication Date |
2015-04-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0040-6090; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.879; 2015 IF: 1.759 |
Call Number |
c:irua:126009 |
Serial |
845 |
Permanent link to this record |
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Author |
Lepoittevin, C.; Hadermann, J.; Malo, S.; Pérez, O.; Van Tendeloo, G.; Hervieu, M. |
Title |
Two variants of the 1/2[110]p(203)p crystallographic shear structures: the phasoid Sr0.61Pb0.18(Fe0.75Mn0.25)O2.29 |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
48 |
Issue |
17 |
Pages |
8257-8262 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
For the composition (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29, a new modulated crystallographic shear structure, related to perovskite, has been synthesized and structurally characterized by transmission electron microscopy. The structure can be described using a monoclinic supercell with cell parameters am = 27.595(2) Å, bm = 3.8786(2) Å, cm = 13.3453(9) Å, and βm = 100.126(5)°, refined from powder X-ray diffraction data. The incommensurate crystallographic shear phases require an alternative approach using the superspace formalism. This allows a unified description of the incommensurate phases from a monoclinically distorted perovskite unit cell and a modulation wave vector. The structure deduced from the high-resolution transmission electron microscopy and high-angle annular dark-field−scanning transmission electron microscopy images is that of a 1/2[110]p(203)p crystallographic shear structure. The structure follows the concept of a phasoid, with two coexisting variants with the same unit cell. The difference is situated at the translational interface, with the local formation of double (phase 2) or single (phase 1) tunnels, where the Pb cations are likely located. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
|
Language |
|
Wos |
000269313500032 |
Publication Date |
2009-07-24 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
11 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.857; 2009 IF: 4.657 |
Call Number |
UA @ lucian @ c:irua:78482 |
Serial |
3786 |
Permanent link to this record |
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|
Author |
Thomassen, G.; Van Dael, M.; Van Passel, S.; You, F. |
Title |
How to assess the potential of emerging green technologies? Towards a prospective environmental and techno-economic assessment framework |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Green Chemistry |
Abbreviated Journal |
Green Chem |
Volume |
21 |
Issue |
18 |
Pages |
4868-4886 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
For sustainable production and consumption, emerging green technologies need to be optimized towards a minimal environmental impact and a maximal economic impact. In an early stage of technology development, more flexibility is available to adapt the technology. Therefore, a prospective environmental and techno-economic assessment is required. The prospective assessment differs at the different stages of technology development, as also the data availability and accuracy evolves. This paper reviews the different prospective technological, economic and environmental assessment methods which have been used to assess the potential of new green chemical technologies. Based on the current best practices, an overarching framework is introduced to assess the technological, economic and environmental potential of an emerging green chemical technology at the different stages of technology development. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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Language |
|
Wos |
000486309300002 |
Publication Date |
2019-08-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9262; 1463-9270 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.125 |
Times cited |
5 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 9.125 |
Call Number |
UA @ admin @ c:irua:163782 |
Serial |
6211 |
Permanent link to this record |
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Author |
Batuk, M.; Vandemeulebroucke, D.; Ceretti, M.; Paulus, W.; Hadermann, J. |
Title |
Topotactic redox cycling in SrFeO2.5+δ explored by 3D electron diffraction in different gas atmospheres |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
Volume |
|
Issue |
|
Pages |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
For oxygen conducting materials applied in solid oxide fuel cells and chemical-looping processes, the understanding of the oxygen diffusion mechanism and the materials’ crystal structure at different stages of the redox reactions is a key parameter to control their performance. In this paper we report the first ever in situ 3D ED experiment in a gas environment and with it uncover the structure evolution of SrFeO2.5 as notably different from that reported from in situ X-ray and in situ neutron powder diffraction studies in gas environments. Using in situ 3D ED on submicron sized single crystals obtained from a high quality monodomain SrFeO2.5 single crystal , we observe the transformation under O2 flow of SrFeO2.5 with an intra- and interlayer ordering of the left and right twisted (FeO4) tetrahedral chains (space group Pcmb) into consecutively SrFeO2.75 with space group Cmmm (at 350°C, 33% O2) and SrFeO3-δ with space group Pm3 ̅m (at 400°C, 100% O2). Upon reduction in H2 flow, the crystals return to the brownmillerite structure with intralayer order, but without regaining the interlayer order of the pristine crystals. Therefore, redox cycling of SrFeO2.5 crystals in O2 and H2 introduces stacking faults into the structure, resulting in an I2/m(0βγ)0s symmetry with variable β. |
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 |
000891928400001 |
Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
2050-7488 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.9 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
Financial support is acknowledged from the FWO-Hercules fund I003218N ‘Infrastructure for imaging nanoscale processes in gas/vapor or liquid environments’, from the University of Antwerp through grant BOF TOP 38689. This work was supported by the European Commission Horizon 2020 NanED grant number 956099. Financial support from the French National Research Agency (ANR) through the project “Structural induced Electronic Complexity controlled by low temperature Topotactic Reaction” (SECTOR No. ANR-14-CE36- 0006-01) is gratefully acknowledged. |
Approved |
Most recent IF: 11.9 |
Call Number |
EMAT @ emat @c:irua:192325 |
Serial |
7229 |
Permanent link to this record |