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Records |
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Author |
Milat, O.; Van Tendeloo, G.; Amelinckx, S.; Babu, T.G.N.; Greaves, C. |
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Title |
Superstructure and structural variants in Sr2CuO2(CO3) |
Type |
A1 Journal article |
|
Year |
1994 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
109 |
Issue |
1 |
Pages |
5-14 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
A1994MY48800002 |
Publication Date |
2002-09-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.133 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
PHYSICS, APPLIED 28/145 Q1 # |
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Call Number |
UA @ lucian @ c:irua:99919 |
Serial |
3384 |
Permanent link to this record |
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Author |
Milat, O.; Van Tendeloo, G.; Amelinckx, S.; Babu, T.G.N.; Greaves, C. |
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Title |
The modulated structure of Ca.85CuO2 as studied by means of electron diffraction and microscopy |
Type |
A1 Journal article |
|
Year |
1992 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
97 |
Issue |
2 |
Pages |
405-418 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
A1992HL68700019 |
Publication Date |
2003-12-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.133 |
Times cited |
15 |
Open Access |
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|
Notes |
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Approved |
PHYSICS, APPLIED 47/145 Q2 # |
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Call Number |
UA @ lucian @ c:irua:103042 |
Serial |
3590 |
Permanent link to this record |
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Author |
Milat, O.; Van Tendeloo, G.; Amelinckx, S.; Wright, A.J.; Greaves, C. |
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Title |
Effect of the substitution Ba\leftrightarrow Sr on the Ga-1222 superstructure : an electron diffraction study |
Type |
A1 Journal article |
|
Year |
1995 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
7 |
Issue |
9 |
Pages |
1709-1715 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The superstructure of the RE(2)(Sr0.85-xBaxNd0.15)(2)GaCU2O9 compound is found to change significantly with increasing substitution of Ba for Sr. Most of the changes take place in the (Sr0.85-xBaxNd0.15)O-GaO-(Sr0.85-xBaxNd0.15)O lamella, the rest of the basic structure being hardly affected. The structural changes for O less than or equal to x less than or equal to 0.65 are studied by electron diffraction. The arrangement of the chains of GaO4 tetrahedra in the Ba-free compound becomes disordered at x > 0.25. At x similar to 0.65 a rearrangement of the chains in the GaO layers takes place; they form a meandering arrangement, which can be described on a 4a(p) x 2a(p) x c(p) superlattice. This rearrangement is accompanied by ordering of Ba and Sr atoms in the adjacent (ST0.85-xBaxNd0.15)O layers. A simple scheme is proposed to explain the influence of the substitution of Ba for Sr on the linking of the GaO4 tetrahedra and on the geometry of the ''chains'' in the GaO layer. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
A1995RW21200021 |
Publication Date |
2005-03-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
8.354 |
Times cited |
|
Open Access |
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|
Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:13326 |
Serial |
850 |
Permanent link to this record |
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Author |
Miliani, C.; Monico, L.; Melo, M.J.; Fantacci, S.; Angelin, E.M.; Romani, A.; Janssens, K. |
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Title |
Photochemistry of Artists' Dyes and Pigments : towards better understanding and prevention of colour change in works of art |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
57 |
Issue |
25 |
Pages |
7324-7334 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The absorption of light gives a pigment its colour and its reason for being, but it also creates excited states, that is, new molecules with an energy excess that can be dissipated through degradation pathways. Photodegradation processes provoke long-term, cumulative and irreversible colour changes (fading, darkening, blanching) of which the prediction and prevention are challenging tasks. Of all the environmental risks that affect heritage materials, light exposure is the only one that cannot be controlled without any impact on the optimal display of the exhibit. Light-induced alterations are not only associated with the pigment itself but also with its interactions with support/binder and, in turn, are further complicated by the nature of the environmental conditions. In this Minireview we investigate how chemistry, encompassing multi-scale analytical investigations of works of art, computational modelling and physical and chemical studies contributes to improve our prediction of artwork appearance before degradation and to establish effective preventive conservation strategies. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000434949200006 |
Publication Date |
2018-04-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.994 |
Times cited |
10 |
Open Access |
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|
Notes |
; We acknowledge: ACS and APS for the permission to adapt Figure 1c,d; RSC to adapt Figures 1e, 3c,d and 4a; Wiley and IUCr to adapt Figures 3b and 4b-d; for the detail of a Andean textile in Figure 5, Museum of Fine Arts, Boston, USA; for the illuminated initial in Figure 6, Torre do Tombo (ANTT). Financial support from the H2020 project IPERION-CH (GA. 654028) is gratefully acknowledged. ; |
Approved |
Most recent IF: 11.994 |
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Call Number |
UA @ admin @ c:irua:153184 |
Serial |
5769 |
Permanent link to this record |
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Author |
Minja, A.C.; Ag, K.R.; Raes, A.; Borah, R.; Verbruggen, S.W. |
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Title |
Recent progress in developing non-noble metal-based photocathodes for solar green hydrogen production |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Current Opinion in Chemical Engineering |
Abbreviated Journal |
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Volume |
43 |
Issue |
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Pages |
101000 |
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Keywords |
A1 Journal article; Engineering sciences. Technology |
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Abstract |
Photocathodes play a vital role in photoelectrocatalytic water splitting by acting as catalysts for reducing protons to hydrogen gas when exposed to light. Recent advancements in photocathodes have focused on addressing the limitations of noble metal-based materials. These noble metal-based photocathodes rely on expensive and scarce metals such as platinum and gold as cocatalysts or ohmic back contacts, respectively, rendering the final system less sustainable and costly when applied at scale. This mini-review summarizes the important recent progress in the development of non-noble metal-based photocathodes and their performance in the hydrogen evolution reaction during photoelectrochemical (PEC) water splitting. These advancements bring non-noble metal-based photocathodes closer to their noble metal-based counterparts in terms of performance, thereby paving the way forward toward industrial-scale photoelectrolyzers or PEC cells for green hydrogen production. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001166826200001 |
Publication Date |
2024-01-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2211-3398 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
6.6 |
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 6.6; 2024 IF: 3.403 |
|
Call Number |
UA @ admin @ c:irua:202625 |
Serial |
9080 |
Permanent link to this record |
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Author |
Minjauw, M.M.; Solano, E.; Sree, S.P.; Asapu, R.; Van Daele, M.; Ramachandran, R.K.; Heremans, G.; Verbruggen, S.W.; Lenaerts, S.; Martens, J.A.; Detavernier, C.; Dendooven, J. |
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Title |
Plasma-enhanced atomic layer deposition of silver using Ag(fod)(PEt3) and NH3-plasma |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
Volume |
29 |
Issue |
17 |
Pages |
7114-7121 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
A plasma-enhanced atomic layer deposition (ALD) process using the Ag(fod)(PEt3) precursor [(triethylphosphine)(6,6,7,7,8,8,8-heptafluoro-2,2-dimethy1-3,5-octanedionate)silver(I)] in combination with NH3-plasma is reported. The steady growth rate of the reported process (0.24 +/- 0.03 nm/cycle) was found to be 6 times larger than that of the previously reported Ag ALD process based on the same precursor in combination with H-2-plasma (0.04 +/- 0.02 nm/cycle). The ALD characteristics of the H-2-plasma and NH3-plasma processes were verified. The deposited Ag films were polycrystalline face-centered cubic Ag for both processes. The film morphology was investigated by ex situ scanning electron microscopy and grazing-incidence small-angle X-ray scattering, and it was found that films grown with the NH3-plasma process exhibit a much higher particle areal density and smaller particle sizes on oxide substrates compared to those deposited using the H-2-plasma process. This control over morphology of the deposited Ag is important for applications in catalysis and plasmonics. While films grown with the H-2-plasma process had oxygen impurities (similar to 9 atom %) in the bulk, the main impurity for the NH3-plasma process was nitrogen (similar to 7 atom %). In situ Fourier transform infrared spectroscopy experiments suggest that these nitrogen impurities are derived from NH surface groups generated during the NH3-plasma, which interact with the precursor molecules during the precursor pulse. We propose that the reaction of these surface groups with the precursor leads to additional deposition of Ag atoms during the precursor pulse compared to the H-2-plasma process, which explains the enhanced growth rate of the NH3-plasma process. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000410868600012 |
Publication Date |
2017-08-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
9.466 |
Times cited |
9 |
Open Access |
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|
Notes |
; M.M.M. and J.D. acknowledge the Fonds Wetenschappelijk Onderzoek Vlaanderen (FWO Vlaanderen) for financial support through a personal research grant. We also acknowledge FWO Vlaanderen for providing project funding for this work. We are grateful to the ESRF staff for smoothly running the synchrotron and beamline facilities. We also thank Olivier Janssens for performing the SEM measurements and Stefaan Broekaert for mechanical assistance. J.A.M. acknowledges the Flemish Government for long-term structural funding (Methusalem). ; |
Approved |
Most recent IF: 9.466 |
|
Call Number |
UA @ admin @ c:irua:146757 |
Serial |
5983 |
Permanent link to this record |
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Author |
Mirbagheri, N.; Campos, R.; Ferapontova, E.E. |
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Title |
Electrocatalytic oxidation of water by OH- – and H₂O-capped IrOx nanoparticles electrophoretically deposited on graphite and basal plane HOPG : effect of the substrate electrode |
Type |
A1 Journal article |
|
Year |
2021 |
Publication |
Chemelectrochem |
Abbreviated Journal |
Chemelectrochem |
|
Volume |
8 |
Issue |
9 |
Pages |
1632-1641 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
Iridium oxide (IrOx) is one of the most efficient electrocatalysts for water oxidation reaction (WOR). Here, WOR electrocatalysis by 1.6 nm IrOx nanoparticles (NPs) electrophoretically deposited onto spectroscopic graphite (Gr) and basal plane highly ordered pyrolytic graphite (HOPG) was studied as a function of NPs' capping ligands and electrodeposition substrate. On Gr, OH-- and H2O-capped NPs exhibited close sub-monolayer surface coverages and specific electrocatalytic activity of 18.9-23.5 mA nmol(-1) of Ir-IV/V sites, at 1 V and pH 7. On HOPG, OH--capped NPs produced films with a diminished WOR activity of 5.17 +/- 2.40 mA nmol(-1). Electro-wettability-induced changes impeded electrophoretic deposition of H2O-capped NPs on HOPG, WOR currents being 25-fold lower than observed for OH--capped ones. The electrocatalysis efficiency correlated with hydrophilic properties of the substrate electrodes, affecting morphological and as a result catalytic properties of the formed IrOx films. These results, important both for studied and related carbon nanomaterials systems, allow fine-tuning of electrocatalysis by a proper choice of the substrate electrode. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000664219100012 |
Publication Date |
2021-04-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2196-0216 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.136 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 4.136 |
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Call Number |
UA @ admin @ c:irua:179719 |
Serial |
7859 |
Permanent link to this record |
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Author |
Mlinar, V.; Peeters, F.M. |
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Title |
A three-dimensional model for artificial atoms and molecules: influence of substrate orientation and magnetic field dependence |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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Volume |
17 |
Issue |
35 |
Pages |
3687-3695 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000249080100013 |
Publication Date |
2007-07-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0959-9428;1364-5501; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:66124 |
Serial |
3653 |
Permanent link to this record |
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Author |
Mmari, A.G.; Potgieter-Vermaak, S.S.; Uiso, C.B.S.; Makundi, I.N.; Potgieter, J.H.; Van Grieken, R. |
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Title |
Corrosive marine atmosphere investigations in Tanzania: exposure sites and preliminary results |
Type |
A3 Journal article |
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Year |
2007 |
Publication |
Newsletter of the International Global Atmospheric Chemistry Project |
Abbreviated Journal |
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Volume |
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Issue |
36 |
Pages |
13-18 |
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Keywords |
A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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Wos |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:65012 |
Serial |
7739 |
Permanent link to this record |
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Author |
Moggia, G.; Hoekx, S.; Daems, N.; Bals, S.; Breugelmans, T. |
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Title |
Synthesis and characterization of a highly electroactive composite based on Au nanoparticles supported on nanoporous activated carbon for electrocatalysis |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
ChemElectroChem |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-11 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
A facile, “one-pot”, chemical approach to synthesize gold-based nanoparticles finely dispersed on porous activated carbon (Norit) was demonstrated in this work. The pH of the synthesis bath played a critical role in determining the optimal gold-carbon interaction, which enabled a successful deposition of the gold nanoparticles onto the carbon matrix with a maximized metal utilization of 93 %. The obtained AuNP/C nanocomposite was characterized using SEM, HAADF-STEM electron tomography and electrochemical techniques. It was found that the Au nanoparticles, with diameters between 5 and 20 nm, were evenly distributed over the carbon matrix, both inside and outside the pores. Electrochemical characterization indicated that the composite had a very large electroactive surface area (EASA), as high as 282.4 m2 gAu-1. By exploiting its very high EASA, the catalyst was intended to boost the productivity of glucaric acid in the electrooxidation of its precursor, gluconic acid. However, cyclic voltammetry experiments revealed a very limited reactivity towards gluconic acid oxidation, due to the spacial hindrance of gluconic acid molecule which prevented diffusion inside the catalyst nanopores. On the other hand, the as-synthesized nanocomposite promises to be effective towards the ORR, and might thus find potential application as anode catalyst for fuel cells as well as for the scalability of all those electrochemical reactions involving small molecules with high diffusivity and catalysed by noble metals (i. e. CO2, CH4, N2, etc..). Electrocatalysis: Gold nanoparticles with diameter between 5 and 20 nm evenly distributed onto porous activated carbon (Norit) were obtained using a facile “one-pot” chemical synthesis technique with very high metal utilization. The AuNP/C nanocomposite was characterized using SEM, HAADF-STEM electron tomography and electrochemical techniques, revealing a very large electroactive surface area (EASA). The figure shows the HAADF-STEM image (a) and the respective EDX elemental distribution (b) for the AuNP/C composite with 9.3 % Au-loading developed in this work (Au is marked in red and C in green).image |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001060398900001 |
Publication Date |
2023-09-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2196-0216 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4 |
Times cited |
1 |
Open Access |
OpenAccess |
|
Notes |
The research described in this article has not been supported by the Climate, Infrastructure and Environment Executive Agency of the European Commission. The views expressed in this article have not been adopted or in any way approved by the European Commission and do not constitute a statement of the European Commission & apos;s views.r S. Hoekx was supported by Research Foundation Flanders (FWO 1S42623N). The authors would like to thank Prof. Dr. Christophe Vande Velde, University of Antwerp, for the XRD analysis. |
Approved |
Most recent IF: 4; 2023 IF: 4.136 |
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Call Number |
UA @ admin @ c:irua:199210 |
Serial |
8941 |
Permanent link to this record |
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Author |
Momot, A.; Amini, M.N.; Reekmans, G.; Lamoen, D.; Partoens, B.; Slocombe, D.R.; Elen, K.; Adriaensens, P.; Hardy, A.; Van Bael, M.K. |
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Title |
A novel explanation for the increased conductivity in annealed Al-doped ZnO: an insight into migration of aluminum and displacement of zinc |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
19 |
Issue |
40 |
Pages |
27866-27877 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A combined experimental and first-principles study is performed to study the origin of conductivity in
ZnO:Al nanoparticles synthesized under controlled conditions via a reflux route using benzylamine as a
solvent. The experimental characterization of the samples by Raman, nuclear magnetic resonance (NMR)
and conductivity measurements indicates that upon annealing in nitrogen, the Al atoms at interstitial
positions migrate to the substitutional positions, creating at the same time Zn interstitials. We provide
evidence for the fact that the formed complex of AlZn and Zni corresponds to the origin of the Knight
shifted peak (KS) we observe in 27Al NMR. As far as we know, the role of this complex has not been
discussed in the literature to date. However, our first-principles calculations show that such a complex is
indeed energetically favoured over the isolated Al interstitial positions. In our calculations we also
address the charge state of the Al interstitials. Further, Zn interstitials can migrate from Al_Zn and possibly
also form Zn clusters, leading to the observed increased conductivity. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000413290500073 |
Publication Date |
2017-10-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.123 |
Times cited |
26 |
Open Access |
OpenAccess |
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Notes |
We want to thank the Interuniversity Attraction Poles Programme (P7/05) initiated by the Belgian Science Policy Office (BELSPO) for the financial support. We also acknowledge the Research Foundation Flanders (FWO-Vlaanderen) for support via the MULTIMAR WOG project and under project No. G018914. The computational parts were carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules foundation and the Flemish Government (EWI Department). |
Approved |
Most recent IF: 4.123 |
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Call Number |
EMAT @ emat @c:irua:146878 |
Serial |
4760 |
Permanent link to this record |
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Author |
Monico, L.; Chieli, A.; De Meyer, S.; Cotte, M.; de Nolf, W.; Falkenberg, G.; Janssens, K.; Romani, A.; Miliani, C. |
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Title |
Role of the relative humidity and the Cd/Zn stoichiometry in the photooxidation process of cadmium yellows (CdS/Cd1-xZnxS) in oil paintings |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Chemistry: a European journal |
Abbreviated Journal |
Chem-Eur J |
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Volume |
24 |
Issue |
45 |
Pages |
11584-11593 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Cadmium yellows (CdYs) refer to a family of cadmium sulfide pigments, which have been widely used by artists since the late 19th century. Despite being considered stable, they are suffering from discoloration in iconic paintings, such as Joy of Life by Matisse, Flowers in a blue vase by Van Gogh, and The Scream by Munch, most likely due to the formation of CdSO4 center dot nH(2)O. The driving factors of the CdYs degradation and how these affect the overall process are still unknown. Here, we study a series of oil mock-up paints made of CdYs of different stoichiometry (CdS/Cd0.76Zn0.24S) and crystalline structure (hexagonal/ cubic) before and after aging at variable relative humidity under exposure to light and in darkness. Synchrotron radiation-based X-ray methods combined with UV-Vis and FTIR spectroscopy show that: 1) Cd0.76Zn0.24S is more susceptible to photooxidation than CdS; both compounds can act as photocatalysts for the oil oxidation. 2) The photooxidation of CdS/Cd0.76Zn0.24S to CdSO4 center dot nH(2)O is triggered by moisture. 3) The nature of alteration products depends on the aging conditions and the Cd/Zn stoichiometry. Based on our findings, we propose a scheme for the mechanism of the photocorrosion process and the photocatalytic activity of CdY pigments in the oil binder. Overall, our results form a reliable basis for understanding the degradation of CdS-based paints in artworks and contribute towards developing better ways of preserving them for future generations. |
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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 |
000441126900012 |
Publication Date |
2018-06-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0947-6539 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.317 |
Times cited |
5 |
Open Access |
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|
Notes |
; The research was financially supported by the European research project IPERION-CH, funded by the European Commission, H2020-INFRAIA-2014-2015 (Grant agreement n. 654028) and by the BOF-GOA Project SOLARPaint (University of Antwerp Research Council). For the beamtime grants received, we thank the ESRF (experiments n. HG64, HG95 and in-house beamtimes) and PETRA III-DESY (experiments: I-20130221 EC, I-20160126 EC). We are also grateful to Dr. Jan Garrevoet for his contribution to set up the P06-beamline at PETRA III-DESY. ; |
Approved |
Most recent IF: 5.317 |
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Call Number |
UA @ admin @ c:irua:153733 |
Serial |
5821 |
Permanent link to this record |
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Author |
Monico, L.; Cotte, M.; Vanmeert, F.; Amidani, L.; Janssens, K.; Nuyts, G.; Garrevoet, J.; Falkenberg, G.; Glatzel, P.; Romani, A.; Miliani, C. |
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Title |
Damages induced by synchrotron radiation-based X-ray microanalysis in chrome yellow paints and related Cr-compounds : assessment, quantification, and mitigation strategies |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
|
Volume |
92 |
Issue |
20 |
Pages |
14164-14173 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Synchrotron radiation (SR)-based X-ray methods are powerful analytical tools for several purposes. They are widely used to probe the degradation mechanisms of inorganic artists' pigments in paintings, including chrome yellows (PbCr1-xSxO4; 0 <= x <= 0.8), a class of compounds often found in Van Gogh masterpieces. However, the high intensity and brightness of SR beams raise important issues regarding the potential damage inflicted on the analyzed samples. A thorough knowledge of the SR X-ray sensitivity of each class of pigment in the painting matrix is therefore required to find analytical strategies that seek to minimize the damage for preserving the integrity of the analyzed samples and to avoid data misinterpretation. Here, we employ a combination of Cr K-edge X-ray absorption near-edge structure spectroscopy, Cr-K-beta X-ray emission spectroscopy, and X-ray diffraction to monitor and quantify the effects of SR X-rays on the stability of chrome yellows and related Cr compounds and to define mitigation strategies. We found that the SR X-ray beam exposure induces changes in the oxidation state and local coordination environment of Cr ions and leads to a loss of the compound's crystalline structure. The extent of X-ray damage depends on some intrinsic properties of the samples (chemical composition of the pigment and the presence/absence and nature of the binder). It can be minimized by optimizing the overall fluence/dose released to the samples and by working in vacuum and under cryogenic conditions. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000584418100072 |
Publication Date |
2020-09-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
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Call Number |
UA @ admin @ c:irua:174363 |
Serial |
7754 |
Permanent link to this record |
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Author |
Monico, L.; Janssens, K.; Cotte, M.; Sorace, L.; Vanmeert, F.; Brunetti, B.G.; Miliani, C. |
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Title |
Chromium speciation methods and infrared spectroscopy for studying the chemical reactivity of lead chromate-based pigments in oil medium |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Microchemical journal
T2 – TECHNART Conference, APR 27-30, 2015, Catania, ITALY |
Abbreviated Journal |
Microchem J |
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Volume |
124 |
Issue |
|
Pages |
272-282 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Environmental factors, such as light, humidity and temperature are triggering agents for the alteration of organic and/or inorganic constituents of oil paintings. The oxidation of the organic material is favored by increasing of relative humidity and temperature, whereas processes involving changes of the oxidation states of a number of inorganic pigments (e.g., vermilion, cadmium yellows, zinc yellows, chrome yellows) are mainly activated by light-exposure. In view of the optimization of the long-term conservation and restoration strategies of paintings it is of relevant interest to establish the consequences of thermal parameters (temperature and relative humidity) on the chemical/photochemical-reactivity and the nature of the alteration products of light sensitive-pigments in oil medium. To this aim here we propose a multi-method analytical approach based on the combination of diffuse reflectance UV-Vis, FTIR, synchrotron radiation (SR)-based micro X-ray fluorescence (mu-XRF)/micro-X-ray absorption neat edge structure ()CANES) and electron paramagnetic resonance (EPR) spectroscopies for studying the effects of different relative humidity conditions before and after light exposure on the reactivity of a series of lead chromate-based pigments [such as PbCrO4 center dot PbO (monoclinic), PbCrO4 (monoclinic) and PbCr0.2S0.8O4 (orthorhombic)] in an oil medium. The investigation of paint models was also compared to that of a late 19th century historical orthorhombic PbCr0.4S0.6O4 oil paint. Diffuse reflectance UV-Vis and FTIR spectroscopies were used to obtain information associated with chromatic changes and the formation of organo-metal degradation products at the paint surface. SR-based Cr K-edge mu-XANES/mu-XRF mapping analysis and EPR spectroscopy were employed in a complementary fashion to determine the amount, nature and distribution of Cr(III) and Cr(V)-based alteration compounds within the paints with micrometric spatial resolution. Under the employed thermal aging conditions, lead(II)-carboxylates and reduced Cr-compounds (in abundance of up to about 35% at the surface) have been identified in the lead chromate-based paints. The tendency of chromates to become reduced increased with increasing moisture levels and was favored for the orthorhombic PbCr0.2S0.8O4 compounds. The redox process gave rise to the formation of Cr(V)-species in relative amount much higher than that was formed in the equivalent paint which was exposed only to light. After light-exposure of the thermally aged paints, compounds ascribable to the oxidation of the organic binder were detected for all the types of pigments. Nevertheless, the previous thermal treatment increased the tendency toward photo-reduction of only the PbCr0.2S0.8O4 pigment. For this light-sensitive compound, the thickness variation of the reduced Cr-rich (ca. 70%) photo-alteration layer with moisture levels could be ascribed to a surface passivation phenomenon that had already occurred before photochemical aging. (C) 2015 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000367755600042 |
Publication Date |
2015-09-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0026-265x; 0026-265x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.034 |
Times cited |
23 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.034 |
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Call Number |
UA @ admin @ c:irua:131099 |
Serial |
5519 |
Permanent link to this record |
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Author |
Monico, L.; Janssens, K.; Hendriks, E.; Vanmeert, F.; van der Snickt, G.; Cotte, M.; Falkenberg, G.; Brunetti, B.G.; Miliani, C. |
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Title |
Evidence for degradation of the chrome yellows in Van Gogh's sunflowers : a study using noninvasive in situ methods and synchrotron-radiation-based x-ray techniques |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
54 |
Issue |
47 |
Pages |
13923-13927 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
This paper presents firm evidence for the chemical alteration of chrome yellow pigments in Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam). Noninvasive in situ spectroscopic analysis at several spots on the painting, combined with synchrotron-radiation-based X-ray investigations of two microsamples, revealed the presence of different types of chrome yellow used by Van Gogh, including the lightfast PbCrO4 and the sulfur-rich PbCr1-xSxO4 (x approximate to 0.5) variety that is known for its high propensity to undergo photoinduced reduction. The products of this degradation process, i.e., Cr-III compounds, were found at the interface between the paint and the varnish. Selected locations of the painting with the highest risk of color modification by chemical deterioration of chrome yellow are identified, thus calling for careful monitoring in the future. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000367722500009 |
Publication Date |
2015-10-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.994 |
Times cited |
24 |
Open Access |
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|
Notes |
; We acknowledge financial support from the Italian MIUR project SICH-PRIN (2010329WPF_001) and BELSPO (Brussels) Project S2-ART (SD04A), GOA “SOLARPAINT” (Research Fund Antwerp University, BOF-2015), and FWO (Brussels) projects G.0C12.13, G.0704.08, G.01769.09. We thank ESRF (EC-1051, HG-26) and DESY (I-20120312 EC) for beamtime grants received. Noninvasive analysis of Sunflowers were supported by the EU FP7 programme CHARISMA (Grant 228330) and the Fund Inbev-Baillet Latour (Brussels). L.M. acknowledges financial support from the CNR Short Term Mobility Programme-2013. We thank Muriel Geldof, Luc Megens, Suzan de Groot (The Netherlands Cultural Heritage Agency, RCE), Chiara Grazia, David Buti (CNR-ISTM and SMAArt Centre), and the staff of the Van Gogh Museum for their collaboration. ; |
Approved |
Most recent IF: 11.994; 2015 IF: 11.261 |
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Call Number |
UA @ admin @ c:irua:131110 |
Serial |
5617 |
Permanent link to this record |
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Author |
Monico, L.; Janssens, K.; Miliani, C.; van der Snickt, G.; Brunetti, B.G.; Guidi, M.C.; Radepont, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 4 : artificial aging of model samples of co-precipitates of lead chromate and lead sulfate |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
85 |
Issue |
2 |
Pages |
860-867 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Previous investigations about the darkening of chrome yellow pigments revealed that this form of alteration is attributable to a reduction of the original Cr(VI) to Cr(III), and that the presence of sulfur-containing compounds, most often sulfates, plays a key role during this process. We recently demonstrated that different crystal forms of chrome yellow pigments (PbCrO4 and PbCr1xSxO4) are present in paintings by Vincent van Gogh. In the present work, we show how both the chemical composition and the crystalline structure of lead chromate-based pigments influence their stability. For this purpose, oil model samples made with in-house synthesized powders of PbCrO4 and PbCr1xSxO4 were artificially aged and characterized. We observed a profound darkening only for those paint models made with PbCr1xSxO4, rich in SO42 (x ≥ 0.4), and orthorhombic phases (>30 wt %). Cr and S K-edge micro X-ray absorption near edge structure investigations revealed in an unequivocal manner the formation of up to about 60% of Cr(III)-species in the outer layer of the most altered samples; conversely, independent of the paint models chemical composition, no change in the S-oxidation state was observed. Analyses employing UVvisible diffuse reflectance and Fourier transform infrared spectroscopy were performed on unaged and aged model samples in order to obtain additional information on the physicochemical changes induced by the aging treatment. |
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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 |
000313668400032 |
Publication Date |
2012-10-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
49 |
Open Access |
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Notes |
; This research was supported by grants from ESRF (experiment EC-799), the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16), and the BELSPO-SDD S2-ART (SD/RI/04) project. The text also presents results from GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects G.0704.08 and G.01769.09. The EU FP7 programme CHARISMA (Grant Agreement 228330) and MIUR (PRIN08, Materiali e sistemi innovativi per la conservazione dell'arte contemporanea 2008 FFXXN9) are also acknowledged. ; |
Approved |
Most recent IF: 6.32; 2013 IF: 5.825 |
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Call Number |
UA @ admin @ c:irua:110471 |
Serial |
5569 |
Permanent link to this record |
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Author |
Monico, L.; Janssens, K.; Vanmeert, F.; Cotte, M.; Brunetti, B.G.; van der Snickt, G.; Leeuwestein, M.; Plisson, J.S.; Menu, M.; Miliani, C. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : part 5 : effects of nonoriginal surface coatings into the nature and distribution of chromium and sulfur species in chrome yellow paints |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
86 |
Issue |
21 |
Pages |
10804-10811 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The darkening of lead chromate yellow pigments, caused by a reduction of the chromate ions to Cr(III) compounds, is known to affect the appearance of several paintings by Vincent van Gogh. In previous papers of this series, we demonstrated that the darkening is activated by light and depends on the chemical composition and crystalline structure of the pigments. In this work, the results of Part 2 are extended and complemented with a new study aimed at deepening the knowledge of the nature and distribution of Cr and S species at the interface between the chrome yellow paint and the nonoriginal coating layer. For this purpose, three microsamples from two varnished paintings by Van Gogh and a waxed low relief by Gauguin (all originally uncoated) have been examined. Because nonoriginal coatings are often present in artwork by Van Gogh and contemporaries, the understanding of whether or not their application has influenced the morphological and/or physicochemical properties of the chrome yellow paint underneath is relevant in view of the conservation of these masterpieces. In all the samples studied, microscopic X-ray fluorescence (mu-XRF) and X-ray absorption near edge structure (mu-XANES) investigations showed that Cr(III)-based alteration products are present in the form of grains inside the coating (generally enriched of S species) and also homogeneously widespread at the paint surface. The distribution of Cr(III) species may be explained by the mechanical friction caused by the coating application by brush that picked up and redistributed the superficial Cr compounds, likely already present in the reduced state as result of the photodegradation process. The analysis of the XANES profiles allowed us to obtain new insights into the nature of the Cr(III) alteration products, that were identified as sulfate-, oxide-, organo-metal-, and chloride-based compounds. Building upon the knowledge acquired through the examination of original paint samples and from the investigation of aged model paints in the last Part 4 paper, in this study we aim to characterize a possible relation between the chemical composition of the coating and the chrome yellow degradation pathways by studying photochemically aged model samples covered with a dammar varnish contaminated with sulfide and sulfate salts. Cr speciation results did not show any evidence of the active role of the varnish and added S species on the reduction process of chrome yellows. |
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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 |
000344510200043 |
Publication Date |
2014-10-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
25 |
Open Access |
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Notes |
; This research was supported by the Italian projects PRIN (SICH) and PON (ITACHA). The text also presents results from Interuniversity Attraction Poles Programme Belgian Science Policy (S2-ART project S4DA), GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. ESRF is acknowledged for the grants received (experiments EC-799 and EC-1051). L.M. acknowledges the CNR for the financial support received in the framework of the Short Term Mobility Programme 2013. Thanks are expressed to Ella Hendriks (Van Gogh Museum, Amsterdam) and Muriel Geldof (Cultural Heritage Agency of The Netherlands) for selecting and sharing the information on the cross-section taken from Bank of the Seine. All the staff of the Van Gogh Museum, the Kroller-Muller Museum, and the Musee d'Orsay are acknowledged for the agreeable cooperation. ; |
Approved |
Most recent IF: 6.32; 2014 IF: 5.636 |
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Call Number |
UA @ admin @ c:irua:122100 |
Serial |
5570 |
Permanent link to this record |
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Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Dik, J.; Radepont, M.; Hendriks, E.; Geldof, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 2 : original paint layer samples |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
83 |
Issue |
4 |
Pages |
1224-1231 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The darkening of the original yellow areas painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is a phenomenon widely observed on several paintings by Vincent van Gogh, such as the famous different versions of Sunflowers. During our previous investigations on artificially aged model samples of lead chromate, we established for the first time that darkening of chrome yellow is caused by reduction of PbCrO4 to Cr2O3·2H2O (viridian green), likely accompanied by the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide]. In the second part of this work, in order to demonstrate that this reduction phenomenon effectively takes place in real paintings, we study original paint samples from two paintings of V. van Gogh. As with the model samples, in view of the thin superficial alteration layers that are present, high lateral resolution spectroscopic methods that make use of synchrotron radiation (SR), such as microscopic X-ray absorption near edge (μ-XANES) and X-ray fluorescence spectrometry (μ-XRF) were employed. Additionally, μ-Raman and mid-FTIR analyses were carried out to completely characterize the samples. On both paint microsamples, the local presence of reduced Cr was demonstrated by means of μ-XANES point measurements. The presence of Cr(III) was revealed in specific areas, in some cases correlated to the presence of Ba(sulfate) and/or to that of aluminum silicate compounds. |
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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 |
000287176900012 |
Publication Date |
2011-02-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
84 |
Open Access |
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Notes |
; This research was funded by grants from ESRF (experiment EC-504) and by HASYLAB (experiments 11-20080130 EC and 11-20070157 EC) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Van Gogh Museum, Amsterdam, is acknowledged for their agreeable cooperation and for the authorization to publish the images of the paintings in this article. L.M. was financially supported by the Erasmus Placement in the framework of Lifelong Learning Programme (A.Y. 2009-2010). The EU Community's FP7 Research Infrastructures program under the CHARISMA Project (Grant Agreement 228330) is also acknowledged. ; |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
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Call Number |
UA @ admin @ c:irua:88795 |
Serial |
5571 |
Permanent link to this record |
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Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Verbeeck, J.; Tian, H.; Tan, H.; Dik, J.; Radepont, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
83 |
Issue |
4 |
Pages |
1214-1223 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000287176900011 |
Publication Date |
2011-02-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700;1520-6882; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
6.32 |
Times cited |
113 |
Open Access |
|
|
Notes |
Iuap; Fwo |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
|
Call Number |
UA @ lucian @ c:irua:88794UA @ admin @ c:irua:88794 |
Serial |
632 |
Permanent link to this record |
|
|
|
|
Author |
Morais, E.; Delikonstantis, E.; Scapinello, M.; Smith, G.; Stefanidis, G.D.; Bogaerts, A. |
|
Title |
Methane coupling in nanosecond pulsed plasmas: Correlation between temperature and pressure and effects on product selectivity |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
|
|
Volume |
462 |
Issue |
|
Pages |
142227 |
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
Abstract |
We present a zero-dimensional kinetic model to characterise specifically the gas-phase dynamics of methane
conversion in a nanosecond pulsed discharge (NPD) plasma reactor. The model includes a systematic approach to
capture the nanoscale power discharges and the rapid ensuing changes in electric field, gas and electron temperature,
as well as species densities. The effects of gas temperature and reactor pressure on gas conversion and
product selectivity are extensively investigated and validated against experimental work. We discuss the
important reaction pathways and provide an analysis of the dynamics of the heating and cooling mechanisms. H
radicals are found to be the most populous plasma species and they participate in hydrogenation and dehydrogenation
reactions, which are the dominant recombination reactions leading to C2H4 and C2H2 as main
products (depending on the pressure). |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
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Editor |
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|
Language |
|
Wos |
000983631500001 |
Publication Date |
2023-03-02 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1385-8947 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
15.1 |
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
We gratefully acknowledge financial support by the Flemish Government through the Moonshot cSBO project “Power-to-Olefins” (P2O; HBC.2020.2620). |
Approved |
Most recent IF: 15.1; 2023 IF: 6.216 |
|
Call Number |
PLASMANT @ plasmant @c:irua:195881 |
Serial |
7246 |
Permanent link to this record |
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Author |
Morales-Yanez, F.; Trashin, S.; Hermy, M.; Sariego, I.; Polman, K.; Muyldermans, S.; De Wael, K. |
|
Title |
Fast one-step ultrasensitive detection of toxocara canis antigens by a nanobody-based electrochemical magnetosensor |
Type |
A1 Journal article |
|
Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
Volume |
91 |
Issue |
18 |
Pages |
11582-11588 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
Human toxocariasis (HT) is a cosmopolitan zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis. Current HT diagnostic methods do not discriminate between active and past infections. Here, we present a method to quantify Toxocara excretory/secretory antigen, aiming to identify active cases of HT. High specificity is achieved by employing nanobodies (Nbs), single domain antigen binding fragments from camelid heavy chain-only antibodies. High sensitivity is obtained by the design of an electrochemical magnetosensor with an amperometric read-out. Reliable detection of TES antigen at 10 and 30 pg/mL level was demonstrated in phosphate buffered saline and serum, respectively. Moreover, the assay showed no cross-reactivity with other nematode antigens. To our knowledge, this is the most sensitive method to quantify the TES antigen so far. It also has great potential to develop point of care diagnostic systems in other conditions where high sensitivity and specificity are required. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000487156900016 |
Publication Date |
2019-08-20 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
6.32 |
Times cited |
2 |
Open Access |
|
|
Notes |
; This project was funded by the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO-Flanders, Project G.0189.13N) and BOF UAntwerp. The authors acknowledge Prof. Pierre Dorny (Institute of Tropical Medicine Antwerp) and Dr. Beatrice Nickel (Swiss Institute of Tropical Medicine) for providing the antigens needed for the cross-reactivity experiments. ; |
Approved |
Most recent IF: 6.32 |
|
Call Number |
UA @ admin @ c:irua:163784 |
Serial |
5621 |
Permanent link to this record |
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|
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Author |
Moro, G.; Barich, H.; Driesen, K.; Montiel, N.F.; Neven, L.; Mendonca, C.D.; Thiruvottriyur Shanmugam, S.; Daems, E.; De Wael, K. |
|
Title |
Unlocking the full power of electrochemical fingerprinting for on-site sensing applications |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Analytical And Bioanalytical Chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
|
Volume |
|
Issue |
|
Pages |
1-14 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
Electrochemical sensing for the semi-quantitative detection of biomarkers, drugs, environmental contaminants, food additives, etc. shows promising results in point-of-care diagnostics and on-site monitoring. More specifically, electrochemical fingerprint (EF)-based sensing strategies are considered an inviting approach for the on-site detection of low molecular weight molecules. The fast growth of electrochemical sensors requires defining the concept of direct electrochemical fingerprinting in sensing. The EF can be defined as the unique electrochemical signal or pattern, mostly recorded by voltammetric techniques, specific for a certain molecule that can be used for its quantitative or semi-quantitative identification in a given analytical context with specified circumstances. The performance of EF-based sensors can be enhanced by considering multiple features of the signal (i.e., oxidation or reduction patterns), in combination with statistical data analysis or sample pretreatments or by including electrode surface modifiers to enrich the EF. In this manuscript, some examples of EF-based sensors, strategies to improve their performances, and open challenges are discussed to unlock the full power of electrochemical fingerprinting for on-site sensing applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000523396300002 |
Publication Date |
2020-04-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.3 |
Times cited |
3 |
Open Access |
|
|
Notes |
; The presented review is the result of a concerted effort and fruitful discussions among enthusiastic, young, and (for the occasion) female researchers of the AXES research group, each of them with specific expertise and background, under the guidance of the corresponding author. The authors acknowledge FWO-Flanders, BOF-UA, IOF-UA, FAPESP and EU for funding. ; |
Approved |
Most recent IF: 4.3; 2020 IF: 3.431 |
|
Call Number |
UA @ admin @ c:irua:168563 |
Serial |
6647 |
Permanent link to this record |
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Author |
Moro, G.; Bottari, F.; Liberi, S.; Covaceuszach, S.; Cassetta, A.; Angelini, A.; De Wael, K.; Moretto, L.M. |
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Title |
Covalent immobilization of delipidated human serum albumin on poly(pyrrole-2-carboxylic) acid film for the impedimetric detection of perfluorooctanoic acid |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Bioelectrochemistry |
Abbreviated Journal |
Bioelectrochemistry |
|
Volume |
134 |
Issue |
|
Pages |
107540 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
The immobilization of biomolecules at screen printed electrodes for biosensing applications is still an open challenge. To enrich the toolbox of bioelectrochemists, graphite screen printed electrodes (G-SPE) were modified with an electropolymerized film of pyrrole-2-carboxilic acid (Py-2-COOH), a pyrrole derivative rich in carboxylic acid functional groups. These functionalities are suitable for the covalent immobilization of biomolecular recognition layers. The electropolymerization was first optimized to obtain stable and conductive polymeric films, comparing two different electrolytes: sodium dodecyl sulphate (SDS) and sodium perchlorate. The G-SPE modified with Py-2-COOH in 0.1 M SDS solution showed the required properties and were further tested. A proof-of-concept study for the development of an impedimetric sensor for perfluorooctanoic acid (PFOA) was carried out using the delipidated human serum albumin (hSA) as bioreceptor. The data interpretation was supported by size exclusion chromatography and small-angle X-ray scattering (SEC-SAXS) analysis of the bioreceptor-target complex and the preliminary results suggest the possibility to further develop this biosensing strategy for toxicological and analytical studies. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000579727300004 |
Publication Date |
2020-04-27 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1567-5394 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
5 |
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 5; 2020 IF: 3.346 |
|
Call Number |
UA @ admin @ c:irua:172494 |
Serial |
6477 |
Permanent link to this record |
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Author |
Moro, G.; Bottari, F.; Sleegers, N.; Florea, A.; Cowen, T.; Moretto, L.M.; Piletsky, S.; De Wael, K. |
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Title |
Conductive imprinted polymers for the direct electrochemical detection of beta-lactam antibiotics: The case of cefquinome |
Type |
A1 Journal article |
|
Year |
2019 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
Sensor Actuat B-Chem |
|
Volume |
297 |
Issue |
297 |
Pages |
126786 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
A biomimetic sensor for cefquinome (CFQ) was designed at multi-walled carbon nanotubes modified graphite screen-printed electrodes (MWCNTs-G-SPEs) as a proof-of-concept for the creation of a sensors array for beta-lactam antibiotics detection in milk. The sensitive and selective detection of antibiotic residues in food and environment is a fundamental step in the elaboration of prevention strategies to fight the insurgence of antimicrobial resistance (AMR) as recommended by authorities around the world (EU, WHO, FDA). The detection strategy is based on the characteristic electrochemical fingerprint of the target antibiotic cefquinome. A conducive electropolymerized molecularly imprinted polymer (MIP) coupled with MWCNTs was found to be the optimal electrode modifier, able to provide an increased selectivity and sensitivity for CFQ detection. The design of CFQ-MIP was facilitated by the rational selection of the monomer, 4-aminobenzoic acid (4-ABA). The electropolymerization process of 4-ABA have not been fully elucidated yet; for this reason a thorough study and optimization of electropolymerization conditions was performed to obtain a conducive and stable poly(4-ABA) film. The modified electrodes were characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and cyclic voltammetry (CV). CFQ-MIP were synthesized at MWCNT-G-SPEs by electropolyrnerization in pH approximate to 1 (0.1 M sulphuric acid) with a monomer:template ratio of 5:1. Two different analytical protocols were tested (single and double step detection) to minimize unspecific adsorptions and improve the sensitivity. Under optimal conditions, the lowest CFQ concentration detectable by square wave voltammetry (SWV) at the modified sensor was 50 nM in 0.1 M phosphate buffer pH 2. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000478562700020 |
Publication Date |
2019-07-08 |
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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 |
0925-4005 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
5.401 |
Times cited |
4 |
Open Access |
|
|
Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223. This work was also supported by FWO. ; |
Approved |
Most recent IF: 5.401 |
|
Call Number |
UA @ admin @ c:irua:161777 |
Serial |
5549 |
Permanent link to this record |
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Author |
Moro, G.; Campos, R.; Daems, E.; Moretto, L.M.; De Wael, K. |
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Title |
Haem-mediated albumin biosensing : towards voltammetric detection of PFOA |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Bioelectrochemistry: an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry |
Abbreviated Journal |
|
|
Volume |
152 |
Issue |
|
Pages |
108428-7 |
|
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
|
Abstract |
The haem group is a promising redox probe for the design of albumin-based voltammetric sensors. Among the endogenous ligands carried by human serum albumin (hSA), haem is characterised by a reversible redox behaviour and its binding kinetics strongly depend on hSA’s conformation, which, in turn, depends on the presence of other ligands. In this work, the potential applicability of haem, especially hemin, as a redox probe was first tested in a proof-of-concept study using perfluorooctanoic acid (PFOA) as model analyte. PFOA is known to bind hSA by occupying Sudlow’s I site (FA7) which is spatially related to the haem-binding site (FA1). The latter undergoes a conformational change, which is expected to affect hemin’s binding kinetics. To verify this hypothesis, hemin:albumin complexes in the presence/absence of PFOA were first screened by UV–Vis spectroscopy. Once the complex formation was verified, haem was further characterised via electrochemical methods to estimate its electron transfer kinetics. The hemin:albumin:PFOA system was studied in solution, with the aim of describing the multiple equilibria at stake and designing an electrochemical assay for PFOA monitoring. This latter could be integrated with protein-based bioremediation approaches for the treatment of per- and polyfluoroalkyl substances polluted waters. Overall, our preliminary results show how hemin can be applied as a redox probe in albumin-based voltammetric sensing strategies. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000971630400001 |
Publication Date |
2023-03-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
1567-5394 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
5 |
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
|
Approved |
Most recent IF: 5; 2023 IF: 3.346 |
|
Call Number |
UA @ admin @ c:irua:195069 |
Serial |
8876 |
Permanent link to this record |
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Author |
Moro, G.; De Wael, K.; Moretto, L.M. |
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Title |
Challenges in the electrochemical (bio)sensing of non-electroactive food and environmental contaminants |
Type |
A1 Journal article |
|
Year |
2019 |
Publication |
Current opinion in electrochemistry |
Abbreviated Journal |
|
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Volume |
16 |
Issue |
16 |
Pages |
57-65 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
The electrochemical detection of non-electroactive contaminants can be successfully faced via the use of indirect detection strategies. These strategies can provide sensitive and selective responses often coupled with portable and user-friendly analytical tools. Indirect detection strategies are usually based on the change in the signal of an electroactive probe, induced by the presence of the target molecule at a modified electrode. This critical review aims at addressing the developments in indirect electro-sensing strategies for non-electroactive contaminants in food and environmental analysis in the last years (2017-2019). Emphasis is given to the strategy design, the electrode modifiers used and the feasibility of technological transfer. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000485814400010 |
Publication Date |
2019-04-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2451-9103; 2451-9111 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
|
Times cited |
4 |
Open Access |
|
|
Notes |
; ; |
Approved |
Most recent IF: NA |
|
Call Number |
UA @ admin @ c:irua:159574 |
Serial |
5498 |
Permanent link to this record |
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Author |
Morozov, V.; Arakcheeva, A.; Redkin, B.; Sinitsyn, V.; Khasanov, S.; Kudrenko, E.; Raskina, M.; Lebedev, O.; Van Tendeloo, G. |
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Title |
Na2/7Gd4/7MoO4 : a modulated scheelite-type structure and conductivity properties |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
9 |
Pages |
5313-5324 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Scheelite-type compounds with the general formula (A1,A2)n[(B1,B2)O4]m (2/3 ≤ n/m ≤ 3/2) are the subject of large interest owing to their stability, relatively simple preparation, and optical properties. The creation of cation vacancies (□) in the scheelite-type framework and the ordering of A cations and vacancies can be a new factor in controlling the scheelite-type structure and properties. For a long time, cation-deficient Nd3+:M2/7Gd4/7□1/7MoO4 (M = Li, Na) compounds were considered as potential lasers with diode pumping. They have a defect scheelite-type 3D structure (space group I41/a) with a random distribution of Li+(Na+), Gd3+, and vacancies in the crystal. A Na2/7Gd4/7MoO4 single crystal with scheelite-type structure has been grown by the Czochralski method. Transmission electron microscopy revealed that Na2/7Gd4/7MoO4 has a (3 + 2)D incommensurately modulated structure. The (3 + 2)D incommensurately modulated scheelite-type cation-deficient structure of Na2/7Gd4/7MoO4 [super space group I4̅ (αβ0,βα0)00] has been solved from single-crystal diffraction data. The solution of the (3 + 2)D incommensurately modulated structure revealed the partially disordered distribution of vacancies and Na and Gd cations. High-temperature conductivity measurements performed along the [100] and [001] orientation of the single crystal revealed that the conductivity of Na2/7Gd4/7MoO4 at T = 973 K equals σ = 1.13 × 105 Ω1 cm1. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000303952900055 |
Publication Date |
2012-04-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.857 |
Times cited |
37 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
|
Call Number |
UA @ lucian @ c:irua:98385 |
Serial |
3547 |
Permanent link to this record |
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Author |
Morozov, V.; Deyneko, D.; Basoyich, O.; Khaikina, E.G.; Spassky, D.; Morozov, A.; Chernyshev, V.; Abakumov, A.; Hadermann, J. |
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Title |
Incommensurately modulated structures and luminescence properties of the AgxSm(2-x)/3WO4 (x=0.286, 0.2) scheelites as thermographic phosphors |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
Volume |
30 |
Issue |
14 |
Pages |
4788-4798 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Ag+ for Sm3+ substitution in the scheelite-type AgxSm(2-x)/3 square(1-2x)/3WO4 tungstates has been investigated for its influence on the cation-vacancy ordering and luminescence properties. A solid state method was used to synthesize the x = 0.286 and x = 0.2 compounds, which exhibited (3 + 1)D incommensurately modulated structures in the transmission electron microscopy study. Their structures were refined using high resolution synchrotron powder X-ray diffraction data. Under near-ultraviolet light, both compounds show the characteristic emission lines for (4)G(5/2) -> H-6(J) (J = 5/2, 7/2, 9/2, and 11/2) transitions of the Sm3+ ions in the range 550-720 nm, with the J = 9/2 transition at the similar to 648 nm region being dominant for all photoluminescence spectra. The intensities of the (4)G(5/2) -> H-6(9/2) and (4)G(5/2) -> H-6(7/2) bands have different temperature dependencies. The emission intensity ratios (R) for these bands vary reproducibly with temperature, allowing the use of these materials as thermographic phosphors. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
|
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Language |
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Wos |
000440105500037 |
Publication Date |
2018-06-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
9.466 |
Times cited |
2 |
Open Access |
Not_Open_Access |
|
Notes |
; This research was supported by FWO (Project G039211N), Flanders Research Foundation. The research was carried out within the state assignment of FASO of Russia (Themes No. 0339-2016-0007). V.M. thanks the Russian Foundation for Basic Research (Grant 18-03-00611) for financial support. E.G.K. and O.B. acknowledge financial support from the Russian Foundation for Basic Research (Grant 16-03-00510). D.D. thanks the Foundation of the Russian Federation President (Grant MK-3502.2018.5) for financial support. We are grateful to the ESRF for granting the beamtime. V.C. is grateful for the financial support of the Russian Ministry of Science and Education (Project No. RFMEFI61616X0069). We are grateful to the ESRF for the access to ID22 station (experiment MA-3313). ; |
Approved |
Most recent IF: 9.466 |
|
Call Number |
UA @ lucian @ c:irua:153156 |
Serial |
5107 |
Permanent link to this record |
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Author |
Morozov, V.A.; Arakcheeva, A.V.; Chapuis, G.; Guiblin, N.; Rossell, M.D.; Van Tendeloo, G. |
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Title |
KNd(MoO4)2: a new incommensurate modulated structure in the scheelite family |
Type |
A1 Journal article |
|
Year |
2006 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
Volume |
18 |
Issue |
17 |
Pages |
4075-4082 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
|
Wos |
000239758300022 |
Publication Date |
2006-07-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
9.466 |
Times cited |
46 |
Open Access |
|
|
Notes |
Iap V-1 |
Approved |
Most recent IF: 9.466; 2006 IF: 5.104 |
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Call Number |
UA @ lucian @ c:irua:60688 |
Serial |
3538 |
Permanent link to this record |
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Author |
Morozov, V.A.; Arakcheeva, A.V.; Konovalova, V.V.; Pattison, P.; Chapuis, G.; Lebedev, O.I.; Fomichev, V.V.; Van Tendeloo, G. |
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Title |
LiZnNb4O11.5 : a novel oxygen deficient compound in the Nb-rich part of the Li2O-ZnO-Nb2O5 system |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
183 |
Issue |
2 |
Pages |
408-418 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A novel lithium zinc niobium oxide LiZnNb(4)O(11.5) (LZNO) has been found in the Nb-rich part of Li(2)O-ZnO-Nb(2)O(5) system. LZNO, with an original alpha-PbO(2) related structure, has been synthesized by the routine ceramic technique and characterized by X-ray diffraction and transmission electron microscopy (TEM). Reflections belonging to the LZNO phase, observed in X-ray powder diffraction (XRPD) and electron diffraction, have been indexed as monoclinic with unit cell parameters a=17.8358(9)angstrom, b=15.2924(7)angstrom, c=5.0363(3)angstrom and gamma=96.607(5)degrees or as alpha-PbO(2)-like with lattice constants a=4.72420(3)angstrom, b=5.72780(3)angstrom, c=5.03320(3)angstrom, gamma=90.048(16)degrees and modulation vector q=0.3a*+1.1b* indicating a commensurately modulated alpha-PbO(2) related structure. The monoclinic cell is a supercell related to the latter. Using synchrotron powder diffraction data, the structure has been solved and refined as a commensurate modulation (superspace group P112(1)/n(alpha beta 0)00) as well as a supercell (space group P2(1)/b). The superspace description allows us to consider the LZNO structure as a member of the proposed alpha-PbO(2)-Z (3 + 1)D structure type, which unifies both incommensurately and commensurately modulated structures. HRTEM reveals several types of defects in LZNO and structural models for these defects are proposed. Two new phases in Li(2)O-ZnO-Nb(2)O(5) system are predicted on the basis of this detailed HRTEM analysis. (C) 2009 Elsevier Inc. All rights reserved. |
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Place of Publication |
London |
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Wos |
000274497600020 |
Publication Date |
2009-12-17 |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
9 |
Open Access |
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Notes |
Iap-Vi |
Approved |
Most recent IF: 2.299; 2010 IF: 2.261 |
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Call Number |
UA @ lucian @ c:irua:95646 |
Serial |
3542 |
Permanent link to this record |