Records |
Author |
Legrand, S.; van der Snickt, G.; Cagno, S.; Caen, J.; Janssens, K. |
Title |
MA-XRF imaging as a tool to characterize the 16th century heraldic stained-glass panels in Ghent Saint Bavo Cathedral |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Journal of cultural heritage |
Abbreviated Journal |
|
Volume |
40 |
Issue |
|
Pages |
163-168 |
Keywords |
A1 Journal article; Art; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
Abstract |
MA-XRF is a novel macroscopic imaging technique originally developed for easel paintings and recently made available to glass conservators. This paper discusses the first real-life contribution of MA-XRF imaging to a conservation intervention of stained-glass panels. The six panels under study belong to the cathedral building since their creation in 1555-1559 AD. MA-XRF appeared an outstanding tool for first-line screening of stained-glass windows, providing readily interpretable information on glass type, coloring and alteration processes. In particular, the chemical imaging technique allowed distinguishing unambiguously the surviving original glass panes from later additions, thereby ensuring a correct historical understanding. From a more practical point of view, the experiments supplied accurate schemes that can be directly incorporated in condition reports and assist designing the ensuing conservation approach. (C0 2019 Elsevier Masson SAS. All rights reserved. |
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Corporate Author |
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Place of Publication |
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Wos |
000491173800017 |
Publication Date |
2019-06-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1296-2074 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
|
Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:167564 |
Serial |
8191 |
Permanent link to this record |
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Author |
Ricciardi, P.; Legrand, S.; Bertolotti, G.; Janssens, K. |
Title |
Macro X-ray fluorescence (MA-XRF) scanning of illuminated manuscript fragments: potentialities and challenges |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Microchemical journal
T2 – TECHNART Conference, APR 27-30, 2015, Catania, ITALY |
Abbreviated Journal |
Microchem J |
Volume |
124 |
Issue |
|
Pages |
785-791 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Macro X-ray fluorescence scanning (MA-XRF) is gradually becoming an established technique for the non-invasive analytical investigation of painted surfaces. This paper discusses some of the benefits and limitations of employing MA-XRF for the study of manuscript illuminations. Art historical research on this type of artefacts that is based on scientific measurements is often limited by the fact that usually no sampling can take place. Hence there is a need for non-invasive analytical tools that make it possible to conduct systematic investigations. As a representative example of this type of objects, a 15th century Italian manuscript fragment from the collection of the Fitzwilliam Museum in Cambridge (UK) is investigated. The aims of the study were to gain insight into the materials and techniques employed by Renaissance illuminators and to help answer specific questions regarding the fragment's authorship and geographic origin. The complementarity and advantages of MA-XRF mapping versus site-specific analyses are discussed. For this purpose, MA-XRF data are evaluated and compared with the results of other analytical techniques. The interpretation of the elemental maps is discussed along with the challenges faced during the analysis. (C) 2015 Elsevier B.V. All rights reserved. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000367755600096 |
Publication Date |
2015-10-27 |
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 |
0026-265x; 0026-265x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.034 |
Times cited |
24 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.034 |
Call Number |
UA @ admin @ c:irua:144767 |
Serial |
5698 |
Permanent link to this record |
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Author |
Yagmurcukardes, M.; Torun, E.; Senger, R.T.; Peeters, F.M.; Sahin, H. |
Title |
Mg(OH)2-WS2 van der Waals heterobilayer : electric field tunable band-gap crossover |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
94 |
Issue |
94 |
Pages |
195403 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnesium hydroxide [Mg(OH)(2)] has a layered brucitelike structure in its bulk form and was recently isolated as a new member of two-dimensional monolayer materials. We investigated the electronic and optical properties of monolayer crystals of Mg(OH)(2) and WS2 and their possible heterobilayer structure by means of first-principles calculations. It was found that both monolayers of Mg(OH)(2) and WS2 are direct-gap semiconductors and these two monolayers form a typical van der Waals heterostructure with a weak interlayer interaction and a type-II band alignment with a staggered gap that spatially separates electrons and holes. We also showed that an out-of-plane electric field induces a transition from a staggered to a straddling-type heterojunction. Moreover, by solving the Bethe-Salpeter equation on top of single-shot G(0)W(0) calculations, we show that the low-energy spectrum of the heterobilayer is dominated by the intralyer excitons of the WS2 monolayer. Because of the staggered interfacial gap and the field-tunable energy-band structure, the Mg(OH)(2)-WS2 heterobilayer can become an important candidate for various optoelectronic device applications in nanoscale. |
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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 |
000386769400007 |
Publication Date |
2016-11-03 |
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 |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. is supported by a FWOPegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge support from TUBITAK through Project No. 114F397. H.S. acknowledges support from Bilim Akademisi – The Science Academy, Turkey, under the BAGEP program. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:138205 |
Serial |
4364 |
Permanent link to this record |
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Author |
Venturi, F.; Calizzi, M.; Bals, S.; Perkisas, T.; Pasquini, L. |
Title |
Self-assembly of gas-phase synthesized magnesium nanoparticles on room temperature substrates |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Materials research express |
Abbreviated Journal |
Mater Res Express |
Volume |
2 |
Issue |
2 |
Pages |
015007 |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) |
Abstract |
Magnesium nanoparticles (NPs) with initial size in the 10-50 nmrange were synthesized by inert gas condensation under helium flow and deposited on room temperature substrates. The morphology and crystal structure of the NPs ensemble were investigated as a function of the deposition time by complementary electron microscopy techniques, including high resolution imaging and chemical mapping. With increasing amount of material, strong coarsening phenomena were observed at room temperature: small NPs disappeared while large faceted NPs developed, leading to a 5-fold increase of the average NPs size within a few minutes. The extent of coarsening and the final morphology depended also on the nature of the substrate. Furthermore, large single-crystal NPs were seen to arise from the self-organization of primary NPs units, providing a mechanism for crystal growth. The dynamics of the self-assembly process involves the basic steps of NPs sticking, diffusion on substrate, coordinated rotation and attachment/coalescence. Key features are the surface energy anisotropy, reflected by the faceted shape of the NPs, and the low melting point of the material. The observed phenomena have strong implications in relation to the synthesis and stability of nanostructures based on Mg or other elements with similar features. |
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Corporate Author |
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Thesis |
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Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000369978500007 |
Publication Date |
2014-12-31 |
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 |
2053-1591 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.068 |
Times cited |
14 |
Open Access |
Not_Open_Access |
Notes |
; Financial support by COST Action MP1103 'Nanostructured Materials for Solid-State Hydrogen Storage' is gratefully acknowledged. ; |
Approved |
Most recent IF: 1.068; 2015 IF: NA |
Call Number |
UA @ lucian @ c:irua:132275 |
Serial |
4240 |
Permanent link to this record |
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Author |
Bogaerts, R.; van Bockstal, L.; Herlach, F.; Peeters, F.M.; DeRosa, F.; Palmstrøm, C.J.; Allen, S.J. |
Title |
Magnetotransport measurements on thin Ga1-xErxAs epitaxial films in pulsed magnetic fields |
Type |
A1 Journal article |
Year |
1992 |
Publication |
Physica: B : condensed matter |
Abbreviated Journal |
Physica B |
Volume |
177 |
Issue |
|
Pages |
425-429 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnet0transport measurements in pulsed fields up to 46 T and at temperatures between 1.4 and 210 K have been performed on thin semimetallic epitaxial layers of Sc1-xErxAs buried inside insulating GaAs. A consistent description is obtained of the magnetic field dependence of the Hall resistance and the different frequencies of the Shubnikov-de Hass oscillations. |
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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 |
A1992HP25000089 |
Publication Date |
2002-10-17 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0921-4526; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.319 |
Times cited |
12 |
Open Access |
|
Notes |
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Approved |
PHYSICS, APPLIED 47/145 Q2 # |
Call Number |
UA @ lucian @ c:irua:3025 |
Serial |
1935 |
Permanent link to this record |
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Author |
Guzzinati, G.; Béché, A.; McGrouther, D.; Verbeeck, J. |
Title |
Prospects for out-of-plane magnetic field measurements through interference of electron vortex modes in the TEM |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Journal of optics |
Abbreviated Journal |
J Optics-Uk |
Volume |
21 |
Issue |
12 |
Pages |
124002 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Magnetic field mapping in transmission electron microscopy is commonplace, but all conventional methods provide only a projection of the components of the magnetic induction perpendicular to the electron trajectory. Recent experimental advances with electron vortices have shown that it is possible to map the out of plane magnetic induction in a TEM setup via interferometry with a specifically prepared electron vortex state carrying high orbital angular momentum (OAM). The method relies on the Aharonov?Bohm phase shift that the electron undergoes when going through a longitudinal field. Here we show how the same effect naturally occurs for any electron wave function, which can always be described as a superposition of OAM modes. This leads to a clear connection between the occurrence of high-OAM partial waves and the amount of azimuthal rotation in the far field angular distribution of the beam. We show that out of plane magnetic field measurement can thus be obtained with a much simpler setup consisting of a ring-like aperture with azimuthal spokes. We demonstrate the experimental setup and explore the achievable sensitivity of the magnetic field measurement. |
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 |
000499367800001 |
Publication Date |
2019-10-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2040-8978 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.741 |
Times cited |
3 |
Open Access |
|
Notes |
The authors thank V Grillo and T Harvey for interesting and fruitful discussion. GG acknowledges support from a postdoctoral fellow-ship grant from the Fonds Wetenschappelijk Onderzoek – Vlaanderen (FWO). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. AB acknowledges funding from FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy'). DM gratefully acknowledges funding of the FEBID capability through joint funding by University of Glasgow & EPSRC through a Strategic Equipment Grant (EP/P001483/1). |
Approved |
Most recent IF: 1.741 |
Call Number |
UA @ admin @ c:irua:165116 |
Serial |
6319 |
Permanent link to this record |
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Author |
Komendová, L.; Milošević, M.V.; Peeters, F.M. |
Title |
Soft vortex matter in a type-I/type-II superconducting bilayer |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
88 |
Issue |
9 |
Pages |
094515 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnetic flux patterns are known to strongly differ in the intermediate state of type-I and type-II superconductors. Using a type-I/type-II bilayer we demonstrate hybridization of these flux phases into a plethora of unique new ones. Owing to a complicated multibody interaction between individual fluxoids, many different intriguing patterns are possible under applied magnetic field, such as few-vortex clusters, vortex chains, mazes, or labyrinthal structures resembling the phenomena readily encountered in soft-matter physics. However, in our system the patterns are tunable by sample parameters, magnetic field, current, and temperature, which reveals transitions from short-range clustering to long-range ordered phases such as parallel chains, gels, glasses, and crystalline vortex lattices, or phases where lamellar type-I flux domains in one layer serve as a bedding potential for type-II vortices in the other, configurations clearly beyond the soft-matter analogy. |
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 |
000324689900008 |
Publication Date |
2013-09-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
27 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). Insightful discussions with Arkady Shanenko and Edith Cristina Euan Diaz are gratefully acknowledged. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:111167 |
Serial |
3050 |
Permanent link to this record |
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Author |
Crippa, F.; Rodriguez-Lorenzo, L.; Hua, X.; Goris, B.; Bals, S.; Garitaonandia, J.S.; Balog, S.; Burnand, D.; Hirt, A.M.; Haeni, L.; Lattuada, M.; Rothen-Rutishauser, B.; Petri-Fink, A. |
Title |
Phase transformation of superparamagnetic iron oxide nanoparticles via thermal annealing : implications for hyperthermia applications |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS applied nano materials |
Abbreviated Journal |
|
Volume |
2 |
Issue |
2 |
Pages |
4462-4470 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Magnetic hyperthermia has the potential to play an important role in cancer therapy and its efficacy relies on the nanomaterials selected. Superparamagnetic iron oxide nanoparticles (SPIONs) are excellent candidates due to the ability of producing enough heat to kill tumor cells by thermal ablation. However, their heating properties depend strongly on crystalline structure and size, which may not be controlled and tuned during the synthetic process; therefore, a postprocessing is needed. We show how thermal annealing can be simultaneously coupled with ligand exchange to stabilize the SPIONs in polar solvents and to modify their crystal structure, which improves hyperthermia behavior. Using high-resolution transmission electron microscopy, X-ray diffraction, Mossbauer spectroscopy, vibrating sample magnetometry, and lock-in thermography, we systematically investigate the impact of size and ligand exchange procedure on crystallinity, their magnetism, and heating ability. We describe a valid and simple approach to optimize SPIONs for hyperthermia by carefully controlling the size, colloidal stability, and crystallinity. |
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 |
000477917700048 |
Publication Date |
2019-06-27 |
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 |
|
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
18 |
Open Access |
Not_Open_Access |
Notes |
; This work was supported by the Swiss National Science Foundation through the National Center of Competence in Research Bio-Inspired Materials, the Adolphe Merkle Foundation, the University of Fribourg, and the European Society for Molecular Imaging (Grant E141200643). ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:161927 |
Serial |
5393 |
Permanent link to this record |
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Author |
Kleibert, A.; Balan, A.; Yanes, R.; Derlet, P.M.; Vaz, C.A.F.; Timm, M.; Fraile Rodríguez, A.; Béché, A.; Verbeeck, J.; Dhaka, R.S.; Radovic, M.; Nowak, U.; Nolting, F. |
Title |
Direct observation of enhanced magnetism in individual size- and shape-selected 3d transition metal nanoparticles |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
95 |
Issue |
95 |
Pages |
195404 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Magnetic nanoparticles are critical building blocks for future technologies ranging from nanomedicine to spintronics. Many related applications require nanoparticles with tailored magnetic properties. However, despite significant efforts undertaken towards this goal, a broad and poorly understood dispersion of magnetic properties is reported, even within monodisperse samples of the canonical ferromagnetic 3d transition metals. We address this issue by investigating the magnetism of a large number of size- and shape-selected, individual nanoparticles of Fe, Co, and Ni using a unique set of complementary characterization techniques. At room temperature, only superparamagnetic behavior is observed in our experiments for all Ni nanoparticles within the investigated sizes, which range from 8 to 20 nm. However, Fe and Co nanoparticles can exist in two distinct magnetic states at any size in this range: (i) a superparamagnetic state, as expected from the bulk and surface anisotropies known for the respective materials and as observed for Ni, and (ii) a state with unexpected stable magnetization at room temperature. This striking state is assigned to significant modifications of the magnetic properties arising from metastable lattice defects in the core of the nanoparticles, as concluded by calculations and atomic structural characterization. Also related with the structural defects, we find that the magnetic state of Fe and Co nanoparticles can be tuned by thermal treatment enabling one to tailor their magnetic properties for applications. This paper demonstrates the importance of complementary single particle investigations for a better understanding of nanoparticle magnetism and for full exploration of their potential for applications. |
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 |
000400665300002 |
Publication Date |
2017-05-05 |
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 |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
OpenAccess |
Notes |
We thank A. Weber, R. Schelldorfer, and J. Krbanjevic (Paul Scherrer Institut) for technical assistance. This paper was supported by the Swiss Nanoscience Institute, University of Basel. A.F.R. acknowledges support from the MICIIN “Ramón y Cajal” Programme. A.B. and J.V. acknowledge funding from the European Union under the European Research Council (ERC) Starting Grant No. 278510 VORTEX and under a contract for Integrated Infrastructure Initiative ESTEEM2 No. 312483. R.Y. and U.N. thank the Deutsche Forschungsgemeinschaft for financial support via Sonderforschungsbereich 1214. Part of this work was performed at the Surface/Interface: Microscopy (SIM) beamline of the Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland. |
Approved |
Most recent IF: 3.836 |
Call Number |
EMAT @ emat @ c:irua:143634UA @ admin @ c:irua:143634 |
Serial |
4575 |
Permanent link to this record |
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Author |
Khan, A.W.; Jan, F.; Saeed, A.; Zaka-ul-Islam, M.; Abrar, M.; Khattak, N.A.D.; Zakaullah, M. |
Title |
Comparative study of electron temperature and excitation temperature in a magnetic pole enhanced-inductively coupled argon plasma |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Current applied physics |
Abbreviated Journal |
Curr Appl Phys |
Volume |
13 |
Issue |
7 |
Pages |
1241-1246 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Magnetic Pole Enhanced-Inductively Coupled Plasmas (MaPE-ICPs) in analogy to the conventional ICPs exhibit two modes of operation, depending on the power coupling mechanism, i.e., a low power mode with dominant capacitive coupling (E-mode) and a high power mode with dominant inductive coupling (H-mode). A comparative study of the electron temperature measured by a Langmuir probe (T-e(LP)) and the electron excitation temperature (T-exc(OES)) determined by Optical Emission Spectroscopy (OES) is reported in the two distinct modes of a MaPE-ICP operated in argon. The dependence of T-e(LP), T-exc(OES) and their ratio (T-e(LP)/T-exc(OES)) on applied power (5-50 W) and gas pressure (15-60 mTorr) is explored, and the validity of T-exc(OES) as an alternative diagnostic to T-e(LP) is tested in the two modes of MaPE-ICP. The OES based non-invasive measurement of the plasma parameters such as electron temperature is very useful for plasma processing applications in which probe measurements are limited. (C) 2013 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 |
Amsterdam |
Editor |
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Language |
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Wos |
000322631400014 |
Publication Date |
2013-04-17 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1567-1739; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.971 |
Times cited |
13 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.971; 2013 IF: 2.026 |
Call Number |
UA @ lucian @ c:irua:110718 |
Serial |
421 |
Permanent link to this record |
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Author |
Stosic, D.; Mulkers, J.; Van Waeyenberge, B.; Ludermir, T.B.; Milošević, M.V. |
Title |
Paths to collapse for isolated skyrmions in few-monolayer ferromagnetic films |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
95 |
Issue |
21 |
Pages |
214418 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnetic skyrmions are topological spin configurations in materials with chiral Dzyaloshinskii-Moriya interaction (DMI), that are potentially useful for storing or processing information. To date, DMI has been found in few bulk materials, but can also be induced in atomically thin magnetic films in contact with surfaces with large spin-orbit interactions. Recent experiments have reported that isolated magnetic skyrmions can be stabilized even near room temperature in few-atom-thick magnetic layers sandwiched between materials that provide asymmetric spin-orbit coupling. Here we present the minimum-energy path analysis of three distinct mechanisms for the skyrmion collapse, based on ab initio input and the performed atomic-spin simulations. We focus on the stability of a skyrmion in three atomic layers of Co, either epitaxial on the Pt(111) surface or within a hybrid multilayer where DMI nontrivially varies per monolayer due to competition between different symmetry breaking from two sides of the Co film. In laterally finite systems, their constrained geometry causes poor thermal stability of the skyrmion toward collapse at the boundary, which we show to be resolved by designing the high-DMI structure within an extended film with lower or no DMI. |
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 |
000404015500001 |
Publication Date |
2017-06-23 |
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 |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
48 |
Open Access |
|
Notes |
This work was supported by the Research Foundation, Flanders (FWO-Vlaanderen) and Brazilian agency CNPq (Grants No. 442668/2014-7 and No. 140840/2016-8). |
Approved |
Most recent IF: 3.836 |
Call Number |
CMT @ cmt @c:irua:144865 |
Serial |
4704 |
Permanent link to this record |
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|
Author |
Litzius, K.; Leliaert, J.; Bassirian, P.; Rodrigues, D.; Kromin, S.; Lemesh, I.; Zazvorka, J.; Lee, K.-J.; Mulkers, J.; Kerber, N.; Heinze, D.; Keil, N.; Reeve, R.M.; Weigand, M.; Van Waeyenberge, B.; Schuetz, G.; Everschor-Sitte, K.; Beach, G.S.D.; Klaeui, M. |
Title |
The role of temperature and drive current in skyrmion dynamics |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Nature Electronics |
Abbreviated Journal |
|
Volume |
3 |
Issue |
1 |
Pages |
30-36 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnetic skyrmions are topologically stabilized nanoscale spin structures that could be of use in the development of future spintronic devices. When a skyrmion is driven by an electric current it propagates at an angle relative to the flow of current-known as the skyrmion Hall angle (SkHA)-that is a function of the drive current. This drive dependence, as well as thermal effects due to Joule heating, could be used to tailor skyrmion trajectories, but are not well understood. Here we report a study of skyrmion dynamics as a function of temperature and drive amplitude. We find that the skyrmion velocity depends strongly on temperature, while the SkHA does not and instead evolves differently in the low- and high-drive regimes. In particular, the maximum skyrmion velocity in ferromagnetic devices is limited by a mechanism based on skyrmion surface tension and deformation (where the skyrmion transitions into a stripe). Our mechanism provides a complete description of the SkHA in ferromagnetic multilayers across the full range of drive strengths, illustrating that skyrmion trajectories can be engineered for device applications. An analysis of skyrmion dynamics at different temperatures and electric drive currents is used to develop a complete description of the skyrmion Hall angle in ferromagnetic multilayers from the creep to the flow regime and illustrates that skyrmion trajectories can be engineered for device applications. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000510860800012 |
Publication Date |
2020-01-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
11 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:167863 |
Serial |
6625 |
Permanent link to this record |
|
|
|
Author |
Reichhardt, C.; Reichhardt, C.J.O.; Milošević, M.V. |
Title |
Statics and dynamics of skyrmions interacting with disorder and nanostructures |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Reviews of modern physics |
Abbreviated Journal |
Rev Mod Phys |
Volume |
94 |
Issue |
3 |
Pages |
035005-35061 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnetic skyrmions are topologically stable nanoscale particlelike objects that were discovered in 2009. Since that time, intense research interest in the field has led to the identification of numerous compounds that support skyrmions over a range of conditions spanning from cryogenic to room temperatures. Skyrmions can be set into motion under various types of driving, and the combination of their size, stability, and dynamics makes them ideal candidates for numerous applications. At the same time, skyrmions represent a new class of system in which the energy scales of the skyrmion-skyrmion interactions, sample disorder, temperature, and drive can compete. A growing body of work indicates that the static and dynamic states of skyrmions can be influenced strongly by pinning or disorder in the sample; thus, an understanding of such effects is essential for the eventual use of skyrmions in applications. The current state of knowledge regarding individual skyrmions and skyrmion assemblies interacting with quenched disorder or pinning is reviewed. The microscopic mechanisms for skyrmion pinning, including the repulsive and attractive interactions that can arise from impurities, grain boundaries, or nanostructures, are outlined. This is followed by descriptions of depinning phenomena, sliding states over disorder, the effect of pinning on the skyrmion Hall angle, the competition between thermal and pinning effects, the control of skyrmion motion using ordered potential landscapes such as one-or two-dimensional periodic asymmetric substrates, the creation of skyrmion diodes, and skyrmion ratchet effects. Highlighted are the distinctions arising from internal modes and the strong gyrotropic or Magnus forces that cause the dynamical states of skyrmions to differ from those of other systems with pinning, such as vortices in type-II superconductors, charge density waves, or colloidal particles. Throughout this review future directions and open questions related to the and in are also discussed. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000861559900001 |
Publication Date |
2022-09-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0034-6861; 1539-0756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
44.1 |
Times cited |
12 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 44.1 |
Call Number |
UA @ admin @ c:irua:191507 |
Serial |
7339 |
Permanent link to this record |
|
|
|
Author |
Abreu, Y.; Cruz, C.M.; Pinera, I.; Leyva, A.; Cabal, A.E.; van Espen, P. |
Title |
DFT study of the hyperfine parameters and magnetic properties of ZnO doped with 57Fe |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Solid state communications |
Abbreviated Journal |
|
Volume |
185 |
Issue |
|
Pages |
25-29 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Magnetic state of Fe-57 implanted and doped ZnO samples have been reported and studied by Mossbauer spectroscopy at different temperatures. The Mossbauer spectra mainly showed four doublets and three sextets, but some ambiguous identification remains regarding the probe site location and influence of defects in the hyperfine and magnetic parameters. In the present work some possible implantation configurations are suggested and evaluated using Monte Carlo simulation and electronic structure calculations within the density functional theory. Various implantation environments were proposed and studied considering the presence of defects. The obtained Fe-57 hyperfine parameters show a good agreement with the reported experimental values for some of these configurations. The possibility of Fe pair formation, as well as a Zn site vacancy stabilization between he second and third neighborhood of the implantation site, is supported. (C) 2014 Elsevier Ltd. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000333751400007 |
Publication Date |
2014-01-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0038-1098 |
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:116839 |
Serial |
7806 |
Permanent link to this record |
|
|
|
Author |
Karapetrov, G.; Belkin, A.; Iavarone, M.; Fedor, J.; Novosad, V.; Milošević, M.V.; Peeters, F.M. |
Title |
Anisotropic superconductivity and vortex dynamics in magnetically coupled F/S and F/S/F hybrids |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
Volume |
24 |
Issue |
1/2 |
Pages |
905-910 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnetically coupled superconductorferromagnet hybrids offer advanced routes for nanoscale control of superconductivity. Magnetotransport characteristics and scanning tunneling microscopy images of vortex structures in superconductorferromagnet hybrids reveal rich superconducting phase diagrams. Focusing on a particular combination of a ferromagnet with a well-ordered periodic magnetic domain structure with alternating out-of-plane component of magnetization, and a small coherence length superconductor, we find directed nucleation of superconductivity above the domain wall boundaries. We show that near the superconductor-normal state phase boundary the superconductivity is localized in narrow mesoscopic channels. In order to explore the Abrikosov flux line ordering in F/S hybrids, we use a combination of scanning tunneling microscopy and GinzburgLandau simulations. The magnetic stripe domain structure induces periodic local magnetic induction in the superconductor, creating a series of pinninganti-pinning channels for externally added magnetic flux quanta. Such laterally confined Abrikosov vortices form quasi-1D arrays (chains). The transitions between multichain states occur through propagation of kinks at the intermediate fields. At high fields we show that the system becomes nonlinear due to a change in both the number of vortices and the confining potential. In F/S/F hybrids we demonstrate the evolution of the anisotropic conductivity in the superconductor that is magnetically coupled with two adjacent ferromagnetic layers. Stripe magnetic domain structures in both F-layers are aligned under each other, resulting in a directional superconducting order parameter in the superconducting layer. The conductance anisotropy strongly depends on the period of the magnetic domains and the strength of the local magnetization. The anisotropic conductivity of up to three orders of magnitude can be achieved with a spatial critical temperature modulation of 5% of T c. Induced anisotropic properties in the F/S and F/S/F hybrids have a potential for future application in switching and nonvolatile memory elements operating at low temperatures. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000289855700150 |
Publication Date |
2010-10-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1557-1939;1557-1947; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.18 |
Times cited |
2 |
Open Access |
|
Notes |
; This work as well as the use of the Center for Nanoscale Materials and the Electron Microscopy Center at Argonne National Laboratory were supported by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. This work was also supported by the Ministry of Education, Agency for Structural Funds of the European Union, Research and Development Program, under agreement 262 401 200 19. M.V.M. and F. M. P. acknowledge support from the Flemish Science Foundation (FWO-VI), the Belgian Science Policy, the JSPS/ESF-NES program, the ESF-AQDJJ network, and the Vlaanderen-USA bilateral program. ; |
Approved |
Most recent IF: 1.18; 2011 IF: 0.650 |
Call Number |
UA @ lucian @ c:irua:89930 |
Serial |
130 |
Permanent link to this record |
|
|
|
Author |
Doğan, F.; Covaci, L.; Kim, W.; Marsiglio, F. |
Title |
Emerging nonequilibrium bound state in spin-current–local-spin scattering |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
10 |
Pages |
104434 |
Keywords |
A1 Journal article |
Abstract |
Magnetization reversal is a well-studied problem with obvious applicability in computer hard drives. One can accomplish a magnetization reversal in at least one of two ways: application of a magnetic field or through a spin current. The latter is more amenable to a fully quantum-mechanical analysis. We formulate and solve the problem whereby a spin current interacts with a ferromagnetic Heisenberg spin chain, to eventually reverse the magnetization of the chain. Spin flips are accomplished through both elastic and inelastic scattering. A consequence of the inelastic-scattering channel, when it is no longer energetically possible, is the occurrence of a nonequilibrium bound state, which is an emergent property of the coupled local plus itinerant spin system. For certain definite parameter values the itinerant spin lingers near the local spins for some time, before eventually leaking out as an outwardly diffusing state. This phenomenon results in spin-flip dynamics and filtering properties for this type of system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000270383100077 |
Publication Date |
2009-09-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121 |
ISBN |
|
Additional Links |
|
Impact Factor |
3.836 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ |
Serial |
4436 |
Permanent link to this record |
|
|
|
Author |
Breynaert, E.; Emmerich, J.; Mustafa, D.; Bajpe, S.R.; Altantzis, T.; Van Havenbergh, K.; Taulelle, F.; Bals, S.; Van Tendeloo, G.; Kirschhock, C.E.A.; Martens, J.A.; |
Title |
Enhanced self-assembly of metal oxides and metal-organic frameworks from precursors with magnetohydrodynamically induced long-lived collective spin states |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
26 |
Issue |
30 |
Pages |
5173-5178 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Magneto-hydrodynamic generation of long-lived collective spin states and their impact on crystal morphology is demonstrated for three different, technologically relevant materials: COK-16 metal organic framework, manganese oxide nanotubes, and vanadium oxide nano-scrolls. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000340546300015 |
Publication Date |
2014-06-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0935-9648; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
7 |
Open Access |
OpenAccess |
Notes |
IAP-PAI; Marie Curie IEF; 262348 ESMI; 335078 COLOURATOM; 246791 COUNTATOMS; IWT; Methusalem; FWO; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 19.791; 2014 IF: 17.493 |
Call Number |
UA @ lucian @ c:irua:118827 |
Serial |
1053 |
Permanent link to this record |
|
|
|
Author |
Mei, H.; Xu, W.; Wang, C.; Yuan, H.; Zhang, C.; Ding, L.; Zhang, J.; Deng, C.; Wang, Y.; Peeters, F.M. |
Title |
Terahertz magneto-optical properties of bi- and tri-layer graphene |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
30 |
Issue |
17 |
Pages |
175701 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magneto-optical (MO) properties of bi- and tri-layer graphene are investigated utilizing terahertz time-domain spectroscopy (THz TDS) in the presence of a strong magnetic field at room-temperature. In the Faraday configuration and applying optical polarization measurements, we measure the real and imaginary parts of the longitudinal and transverse MO conductivities of different graphene samples. The obtained experimental data fits very well with the classical MO Drude formula. Thus, we are able to obtain the key sample and material parameters of bi- and tri-layer graphene, such as the electron effective mass, the electronic relaxation time and the electron density. It is found that in high magnetic fields the electronic relaxation time tau for bi- and tri-layer graphene increases with magnetic field B roughly in a form tau similar to B-2. Most importantly, we obtain the electron effective mass for bi- and tri-layer graphene at room-temperature under non-resonant conditions. This work shows how the advanced THz MO techniques can be applied for the investigation into fundamental physics properties of atomically thin 2D electronic systems. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000429329500001 |
Publication Date |
2018-03-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
11 |
Open Access |
|
Notes |
; This work was supported by the National Natural Science Foundation of China (11574319, 11304317, 11304272), the Ministry of Science and Technology of China (2011YQ130018), the Center of Science and Technology of Hefei Academy of Science, the Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 2.649 |
Call Number |
UA @ lucian @ c:irua:150715UA @ admin @ c:irua:150715 |
Serial |
4983 |
Permanent link to this record |
|
|
|
Author |
Maignan, A.; Martin, C.; Singh, K.; Simon, C.; Lebedev, O.I.; Turner, S. |
Title |
From spin induced ferroelectricity to dipolar glasses : spinel chromites and mixed delafossites |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
Volume |
195 |
Issue |
|
Pages |
41-49 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Magnetoelectric multiferroics showing coupling between polarization and magnetic order are attracting much attention. For instance, they could be used in memory devices. Metal-transition oxides are provided several examples of inorganic magnetoelectric multiferroics. In the present short review, spinel and delafossite chromites are described. For the former, an electric polarization is evidenced in the ferrimagnetic state for ACr2O4 polycrystalline samples (A=Ni, Fe, Co). The presence of a JahnTeller cation such as Ni2+ at the A site is shown to yield larger polarization values. In the delafossites, substitution by V3+ at the Cr or Fe site in CuCrO2 (CuFeO2) suppresses the complex antiferromagnetic structure at the benefit of a spin glass state. The presence of cation disorder, probed by transmission electron microscopy, favors relaxor-like ferroelectricity. The results on the ferroelectricity of ferrimagnets and insulating spin glasses demonstrate that, in this research field, transition-metal oxides are worth to be studied. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000309783600006 |
Publication Date |
2012-02-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.299 |
Times cited |
27 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 2.299; 2012 IF: 2.040 |
Call Number |
UA @ lucian @ c:irua:101219 |
Serial |
1286 |
Permanent link to this record |
|
|
|
Author |
Nicholas, R.J.; Sasaki, S.; Miura, N.; Peeters, F.M.; Shi, J.M.; Hai, G.Q.; Devreese, J.T.; Lawless, M.J.; Ashenford, D.E.; Lunn, B. |
Title |
Interband magnetooptical studies of resonant polaron coupling in CdTe/Cd1-xMnxTe quantum-wells |
Type |
A1 Journal article |
Year |
1994 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
50 |
Issue |
11 |
Pages |
7596-7601 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
Magnetoreflectivity measurements of the 1s and 2s exciton energies in a CdTe/Cd1-xMnxTe superlattice have been made in magnetic fields up to 45 T, showing the resonant polaron coupling of electrons to LO phonons. Strong reflectivity features are seen for both the 1s and 2s excitons, which show a strong field-dependent spin splitting due to the dilute magnetic barriers. At B-z=0, the 2s exciton feature is observed lying 18 meV above the Is state, and is shifted upward in energy by the magnetic fields. No resonant behavior occurs when the 2s state passes through the LO-phonon energy of 21 meV, but at higher fields of around 20 T, the resonances for both spin states (sigma(+/-)) of the 2s exciton broaden and show a strong anticrossing behavior. These experiments are shown to be in excellent agreement with a theoretical treatment which includes the resonant polaron coupling of the electrons alone. Both experiment and theory demonstrate an extremely strong resonant splitting of the 2s exciton states of approximately 11 meV, which is over 50% of the LO-phonon energy. The dominance of single-particle polaron coupling is attributed to the relative sizes of the polaron (35 Angstrom A) and the exciton (50 Angstrom A) radius. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
A1994PJ43700045 |
Publication Date |
2002-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.736 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:99837 |
Serial |
1687 |
Permanent link to this record |
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|
|
Author |
Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Magnetotransport in periodically modulated bilayer graphene |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
24 |
Pages |
245426-245426,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnetotransport in bilayer graphene in the presence of a weak and periodic potential is investigated in the presence of a perpendicular magnetic field B. The modulation broadens the Landau levels into bands and for weak magnetic fields leads to the well-known Weiss oscillations in their bandwidth and their transport coefficients at very low B and to the Shubnikov-de Haas oscillations at larger B. The amplitude of the Weiss oscillations is severely reduced if the periodic potentials applied to the two layers oscillate out of phase. We also contrast some results with those corresponding to single-layer graphene. Relative to them the flat-band condition and the oscillation amplitude differ substantially, due to the interlayer coupling, and agree only when this coupling is extremely weak. We further show that the Hall conductivity exhibits the well-known steps at half-integer and integer multiples of 4e(2)/h in single-layer and bilayer graphene, respectively, even for very weak magnetic fields. The results are pertinent to weak and periodic corrugations when the potential modulation dominates the strain-induced magnetic modulation. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000305253600012 |
Publication Date |
2012-06-14 |
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 |
21 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CON-GRAN), and the Canadian NSERC Grant No. OGP0121756. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:99077 |
Serial |
1934 |
Permanent link to this record |
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|
|
Author |
Yan, Y.; Wang, L.-X.; Ke, X.; Van Tendeloo, G.; Wu, X.-S.; Yu, D.-P.; Liao, Z.-M. |
Title |
High-mobility Bi2Se3 nanoplates manifesting quantum oscillations of surface states in the sidewalls |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
4 |
Issue |
|
Pages |
3817-7 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Magnetotransport measurements of topological insulators are very important to reveal the exotic topological surface states for spintronic applications. However, the novel properties related to the surface Dirac fermions are usually accompanied by a large linear magnetoresistance under perpendicular magnetic field, which makes the identification of the surface states obscure. Here, we report prominent Shubnikov-de Haas (SdH) oscillations under an in-plane magnetic field, which are identified to originate from the surface states in the sidewalls of topological insulator Bi2Se3 nanoplates. Importantly, the SdH oscillations appear with a dramatically weakened magnetoresistance background, offering an easy path to probe the surface states directly when the coexistence of surface states and bulk conduction is inevitable. Moreover, under a perpendicular magnetic field, the oscillations in Hall conductivity have peak-to-valley amplitudes of 2 e(2)/h, giving confidence to achieve a quantum Hall effect in this system. A cross-section view of the nanoplate shows that the sidewall is (015) facet dominant and therefore forms a 586 angle with regard to the top/ bottom surface instead of being perpendicular; this gives credit to the surface states' behavior as two-dimensional transport. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000330044700008 |
Publication Date |
2014-01-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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 |
31 |
Open Access |
|
Notes |
ERC grant Nu246791 – COUNTATOMS |
Approved |
Most recent IF: 4.259; 2014 IF: 5.578 |
Call Number |
UA @ lucian @ c:irua:114815 |
Serial |
1436 |
Permanent link to this record |
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|
Author |
van der Burgt, M.; Karavolas, V.C.; Peeters, F.M.; Singleton, J.; Nicholas, R.J.; Herlach, F.; Harris, J.J.; Van Hove, M.; Borghs, G. |
Title |
Magnetotransport in a pseudomorphic GaAs/Ga0.8In0.2As/Ga0.75Al0.25As heterostructure with a Si \delta-doping layer |
Type |
A1 Journal article |
Year |
1995 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
52 |
Issue |
16 |
Pages |
12218-12231 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Magnetotransport properties of a pseudomorphic GsAs/Ga0.8In0.2As/Ga0.75Al0.25As heterostructure are investigated in pulsed magnetic fields up to 50 T and at temperatures of T = 1.4 and 4.2 K. The structure studied consists of a Si delta layer parallel to a Ga0.8In0.2As quantum well (QW). The dark electron density of the structure is n(c) = 1.67 x 10(16) m(-2). By illumination the density can be increased up to a factor of 4; this way the second subband in the Ga0.08In0.2As QW can become populated as well as the Si delta layer. The presence of electrons in the delta layer results in drastic changes in the transport data, especially at magnetic fields beyond 30 T. The phenomena observed are interpreted as (i) magnetic freeze-out of carriers in the delta layer when a low density of electrons is present in the delta layer, and (ii) quantization of the electron motion in the two-dimensional electron gases in both the Ga0.8In0.2As QW and the Si delta layer in the case of high densities. These conclusions are corroborated by the numerical results of our theoretical model. We obtain satisfactory agreement between model and experiment. |
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 |
A1995TB96600102 |
Publication Date |
2002-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.736 |
Times cited |
43 |
Open Access |
|
Notes |
|
Approved |
PHYSICS, APPLIED 28/145 Q1 # |
Call Number |
UA @ lucian @ c:irua:99708 |
Serial |
1933 |
Permanent link to this record |
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|
|
Author |
Brault, P.; Neyts, E.C. |
Title |
Molecular dynamics simulations of supported metal nanocatalyst formation by plasma sputtering |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Catalysis today |
Abbreviated Journal |
Catal Today |
Volume |
256 |
Issue |
256 |
Pages |
3-12 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Magnetron sputtering is a widely used physical vapor deposition technique for deposition and formation of nanocatalyst thin films and clusters. Nevertheless, so far only few studies investigated this formation process at the fundamental level. We here review atomic scale molecular dynamics simulations aimed at elucidating the nanocatalyst growth process through magnetron sputtering. We first introduce the basic magnetron sputtering background and machinery of molecular dynamics simulations, and then describe the studies conducted in this field so far. We also present a perspective view on how the field may be developed further. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000360085300002 |
Publication Date |
2015-02-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0920-5861; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.636 |
Times cited |
18 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.636; 2015 IF: 3.893 |
Call Number |
c:irua:127408 |
Serial |
2174 |
Permanent link to this record |
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|
Author |
da Silva, A.T.; Legrand, S.; van der Snickt, G.; Featherstone, R.; Janssens, K.; Bottinelli, G. |
Title |
MA-XRF imaging on Rene Magritte's La condition humaine : insights into the artist's palette and technique and the discovery of a third quarter of La pose enchantee |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Heritage science |
Abbreviated Journal |
|
Volume |
5 |
Issue |
|
Pages |
37 |
Keywords |
A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Magritte's composition La condition humaine, 1935 was found to conceal under its paint layers an entire quarter of a lost composition by the artist, until recently only known from a small black/white catalogue illustration-La pose enchantee, 1927. This study is the latest contribution to the discovery of the artist's missing painting, now known to have been cut into four parts and re-used by Magritte as the support for new compositions. Non-destructive analytical and examination methods and specifically macroscopic X-ray fluorescence (MAXRF) scanning and conventional X-ray radiography (XRR) were the two non-destructive analytical and examination methods used to study both compositions and add to the existing knowledge on the artist's palette during both periods. The first method is capable of identifying the presence and the distribution of key chemical elements present in artists' materials. In some instances elemental mapping provided useful information on the hidden painting, but conventional X-ray radiography (XRR) enabled a better visualisation of the form and paint application of the underlying composition. Furthermore, the turnover edges of the canvas reveal after over 80 years the artist's palette directly to the viewer. Additional XRF scanning of this exposed paint has confirmed and added to the existing research published to date of this lost painting, including a proposed colour reconstruction, but at the same time highlighting the need for further analytical research involving both non-destructive point analysis and the use of paint samples. |
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 |
000410413500001 |
Publication Date |
2017-08-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2050-7445 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
7 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:145695 |
Serial |
5696 |
Permanent link to this record |
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|
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Author |
Van Tendeloo, M.; Xie, Y.; Van Beeck, W.; Zhu, W.; Lebeer, S.; Vlaeminck, S.E. |
Title |
Oxygen control and stressor treatments for complete and long-term suppression of nitrite-oxidizing bacteria in biofilm-based partial nitritation/anammox |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Bioresource Technology |
Abbreviated Journal |
Bioresource Technol |
Volume |
342 |
Issue |
|
Pages |
125996 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Mainstream nitrogen removal by partial nitritation/anammox (PN/A) can realize energy and cost savings for sewage treatment. Selective suppression of nitrite oxidizing bacteria (NOB) remains a key bottleneck for PN/A implementation. A rotating biological contactor was studied with an overhead cover and controlled air/N2 inflow to regulate oxygen availability at 20 °C. Biofilm exposure to dissolved oxygen concentrations < 0.51 ± 0.04 mg O2 L-1 when submerged in the water and < 1.41 ± 0.31 mg O2 L-1 when emerged in the headspace (estimated), resulted in complete and long-term NOB suppression with a low relative nitrate production ratio of 10 ± 4%. Additionally, weekly biofilm stressor treatments with free ammonia (FA) (29 ± 1 mg NH3-N L-1 for 3 h) could improve the NOB suppression while free nitrous acid treatments had insufficient effect. This study demonstrated the potential of managing NOB suppression in biofilm-based systems by oxygen control and recurrent FA exposure, opening opportunities for resource efficient nitrogen removal. |
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 |
000704455300005 |
Publication Date |
2021-09-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0960-8524 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.651 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 5.651 |
Call Number |
UA @ admin @ c:irua:181301 |
Serial |
8355 |
Permanent link to this record |
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Author |
Doevenspeck, J.; Zografos, O.; Gurunarayanan, S.; Lauwereins, R.; Raghavan, P.; Sorée, B. |
Title |
Design and simulation of plasmonic interference-based majority gate |
Type |
A1 Journal article |
Year |
2017 |
Publication |
AIP advances |
Abbreviated Journal |
|
Volume |
7 |
Issue |
6 |
Pages |
065116 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Major obstacles in current CMOS technology, such as the interconnect bottleneck and thermal heat management, can be overcome by employing subwavelength-scaled light in plasmonic waveguides and devices. In this work, a plasmonic structure that implements the majority (MAJ) gate function is designed and thoroughly studied through simulations. The structure consists of three merging waveguides, serving as the MAJ gate inputs. The information of the logic signals is encoded in the phase of transmitted surface plasmon polaritons (SPP). SPPs are excited at all three inputs and the phase of the output SPP is determined by theMAJof the input phases. The operating dimensions are identified and the functionality is verified for all input combinations. This is the first reported simulation of a plasmonic MAJ gate and thus contributes to the field of optical computing at the nanoscale. (C) 2017 Author(s). |
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 |
000404621200036 |
Publication Date |
2017-06-23 |
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 |
2158-3226 |
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:152632 |
Serial |
7764 |
Permanent link to this record |
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Author |
Peng, X.; Peng, H.; Zhao, K.; Zhang, Y.; Xia, F.; Lyu, J.; Van Tendeloo, G.; Sun, C.; Wu, J. |
Title |
Direct visualization of atomic-scale heterogeneous structure dynamics in MnO₂ nanowires |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
13 |
Issue |
28 |
Pages |
33644-33651 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Manganese oxides are attracting great interest owing to their rich polymorphism and multiple valent states, which give rise to a wide range of applications in catalysis, capacitors, ion batteries, and so forth. Most of their functionalities are connected to transitions among the various polymorphisms and Mn valences. However, their atomic-scale dynamics is still a great challenge. Herein, we discovered a strong heterogeneity in the crystalline structure and defects, as well as in the Mn valence state. The transitions are studied by in situ transmission electron microscopy (TEM), and they involve a complex ordering of [MnO6] octahedra as the basic building tunnels. MnO2 nanowires synthesized using solution-based hydrothermal methods usually exhibit a large number of multiple polymorphism impurities with different tunnel sizes. Upon heating, MnO2 nanowires undergo a series of stoichiometric polymorphism changes, followed by oxygen release toward an oxygen-deficient spinel and rock-salt phase. The impurity polymorphism exhibits an abnormally high stability with interesting small-large-small tunnel size transition, which is attributed to a preferential stabilizer (K+) concentration, as well as a strong competition of kinetics and thermodynamics. Our results unveil the complicated intergrowth of polymorphism impurities in MnO2, which provide insights into the heterogeneous kinetics, thermodynamics, and transport properties of the tunnel-based building blocks. |
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 |
000677540900101 |
Publication Date |
2021-07-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.504 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 7.504 |
Call Number |
UA @ admin @ c:irua:180450 |
Serial |
6861 |
Permanent link to this record |
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Author |
Cassimon, J.; Kovács, A.; Neyts, E.; Cornet, I.; Billen, P. |
Title |
Deacetylation of mannosylerythritol lipids in hydrophobic natural deep eutectic solvents |
Type |
A1 Journal article |
Year |
2023 |
Publication |
European journal of organic chemistry |
Abbreviated Journal |
|
Volume |
27 |
Issue |
5 |
Pages |
e202300934-10 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Biochemical Wastewater Valorization & Engineering (BioWaVE); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) |
Abstract |
Mannosylerythritol lipids (MELs) are a promising group of biosurfactants due to their high fermentation yield, selfassembly and biological activity. During fermentation by Pseudozyma aphidis, a mixture of MELs with different levels of acylation is formed, of which the fully deacetylated form is the most valuable. In order to reduce the environmental impact of deacetylation, an enzymatic process using natural deep eutectic solvents (NADES) has been developed. We tested the deacetylation of a purified MELs mixture with immobilized Candida antarctica lipase B enzyme and 2-ethylhexanol as co-substrate in 140 h reactions with different NADES. We identified hydrophobic NADES systems with similar yields and kinetics as in pure 2-ethylhexanol solvent. Our results indicate that deacetylation of MELs mixtures in NADES as a solvent is possible with yields comparable to pure co-substrate and that hydrophobic NADES without carboxylic acid compounds facilitate the reaction to the greatest extent. |
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 |
2023-12-12 |
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 |
1434-193x; 1099-0690 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
2.8 |
Times cited |
|
Open Access |
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Notes |
|
Approved |
Most recent IF: 2.8; 2023 IF: 2.834 |
Call Number |
UA @ admin @ c:irua:201382 |
Serial |
9017 |
Permanent link to this record |
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Author |
Pintucci, C.; Carballa, M.; Varga, S.; Sarli, J.; Peng, L.; Bousek, J.; Pedizzi, C.; Ruscalleda, M.; Tarragó, E.; Prat, D.; Colica, G.; Picavet, M.; Colsen, J.; Benito, O.; Balaguer, M.; Puig, S.; Lema, J.M.; Colprim, J.; Fuchs, W.; Vlaeminck, S.E. |
Title |
The ManureEcoMine pilot installation : advanced integration of technologies for the management of organics and nutrients in livestock waste |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Water science and technology |
Abbreviated Journal |
|
Volume |
75 |
Issue |
6 |
Pages |
1281-1293 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Manure represents an exquisite mining opportunity for nutrient recovery (nitrogen and phosphorus), and for their reuse as renewable fertilisers. The ManureEcoMine proposes an integrated approach of technologies, operated in a pilot-scale installation treating swine manure (83.7%) and Ecofrit® (16.3%), a mix of vegetable residues. Thermophilic anaerobic digestion was performed for 150 days, the final organic loading rate was 4.6 kgCOD m−3 d−1, with a CH4 production of 1.4 Nm3 m−3 d−1. The digester was coupled to an ammonia side-stream stripping column and a scrubbing unit for free ammonia inhibition reduction in the digester and nitrogen recovery as ammonium sulphate. The stripped digestate was recirculated daily in the digester for 15 days (68% of the digester volume), increasing the gas production rate by 27%. Following a decanter centrifuge, the digestate liquid fraction was treated with an ultrafiltration membrane. The filtrate was fed into a struvite reactor, with a phosphorus recovery efficiency of 83% (as orthophosphate). Acidification of digestate could increment the soluble orthophosphate concentration up to 4 times, enhancing phosphorus enrichment in the liquid fraction and its recovery via struvite. A synergistic combination of manure processing steps was demonstrated to be technologically feasible to upgrade livestock waste into refined, concentrated fertilisers. |
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 |
000397590800003 |
Publication Date |
2016-12-10 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
0273-1223; 1996-9732 |
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:139911 |
Serial |
8200 |
Permanent link to this record |