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Records |
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Author |
Cornil, D.; Li, H.; Wood, C.; Pourtois, G.; Bredas, J.-L.; Cornil, J. |
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Title |
Work-function modification of Au and Ag surfaces upon deposition of self-assembled monolayers : influence of the choice of the theoretical approach and the thiol decomposition scheme |
Type |
A1 Journal article |
| |
Year  |
2013 |
Publication |
ChemPhysChem : a European journal of chemical physics and physical chemistry |
Abbreviated Journal |
Chemphyschem |
| |
Volume |
14 |
Issue |
13 |
Pages |
2939-2946 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
We have characterized theoretically the work-function modifications of the (111) surfaces of gold and silver upon deposition of self-assembled monolayers based on methanethiol and trifluoromethanethiol. A comparative analysis is made between the experimental results and those obtained from two widely used approaches based on density functional theory. The contributions to the total work-function modifications are estimated on the basis of two decomposition schemes of the thiol molecules that have been proposed in the literature. The contributions are found to differ significantly between the two approaches, as do the corresponding adsorption energies. |
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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 |
Weinheim |
Editor |
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Language |
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Wos |
000324316000014 |
Publication Date |
2013-07-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1439-4235; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.075 |
Times cited |
9 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 3.075; 2013 IF: 3.360 |
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Call Number |
UA @ lucian @ c:irua:112278 |
Serial |
3923 |
| Permanent link to this record |
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Author |
Krupińska, B.; Van Grieken, R.; De Wael, K. |
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Title |
Air quality monitoring in a museum for preventive conservation : results of a three-year study in the Plantin-Moretus Museum in Antwerp, Belgium |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
| |
Volume |
110 |
Issue |
|
Pages |
350-360 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Through different research projects on air quality in museums, researcher and conservators try identifying various risks of air pollution on materials. The conclusions may be later translated into specific actions for a maximum preservation of the museum collections, a process known as preventive conservation. Air pollution is a particular problem in historical buildings such as museums, because they were not originally built to exhibit and protect art objects in a sustainable way. This article reports on the data and results that were obtained during 10 sampling campaigns, in the period between November 2008 and February 2012 in a museum in Antwerp (Belgium), i.e. Plantin-Moretus Museum/Print Room. Different pollutants were measured inside and outside the museum such as inorganic gases, particulate matter and black carbon. The report specifically addresses environmental factors that may be responsible for damage to the collections present in museums. Thanks to the knowledge about the current situation in the museum, accurate solutions regarding preventive conservation, in general, are suggested. |
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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 |
000326851200051 |
Publication Date |
2013-05-21 |
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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 |
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 |
46 |
Open Access |
|
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Notes |
; The presented work was realised in the frame of the project Preventive conservation/preservation in the museum Plantin-Moretus/Prentenkabinet, Antwerp, financed by the Flemish Government. Special thanks are due to Mrs Hanne Moris and Mrs Elke van Herck and all the staff of the Museum Plantin-Moretus/Print Room in Antwerp for their sincere interest in this work and their eager assistance during all the sampling campaigns. VMM and Dr. Edward Roekens is acknowledged for sharing the black carbon measurements. Barbara Krupinska is supported as PhD student by the Flemish Fund for Scientific Research (FWO, Belgium). ; |
Approved |
Most recent IF: 3.034; 2013 IF: 3.583 |
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Call Number |
UA @ admin @ c:irua:108402 |
Serial |
5460 |
| 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 |
| |
Year |
2013 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| |
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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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 |
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 |
Anaf, W.; Janssens, K.; De Wael, K. |
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Title |
Formation of metallic mercury during photodegradation/photodarkening of \alpha-HgS : electrochemical evidence |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
52 |
Issue |
48 |
Pages |
12568-12571 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Das rote Pigment α-HgS neigt in Gegenwart von Licht und Chloridionen zur Schwärzung. Als Grund für die Zersetzung und Entfärbung werden die Bildung von (schwarzem) β-HgS oder Quecksilbermetall vermutet, doch diese Substanzen wurden noch nicht auf natürlich oder künstlich zersetzter HgS-Farbe nachgewiesen. Elektrochemische Experimente belegen nun die Bildung von Quecksilbermetall in Gegenwart von Licht und Chloridionen. |
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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 |
000327582900015 |
Publication Date |
2013-10-04 |
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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 |
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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 |
19 |
Open Access |
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Notes |
; The authors acknowledge L. Klaassen for valuable discussions and providing samples. We acknowledge financial support from the SDD programme (S2-ART project) of the Belgian Federal Goverment. ; |
Approved |
Most recent IF: 11.994; 2013 IF: 11.336 |
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Call Number |
UA @ admin @ c:irua:111265 |
Serial |
5626 |
| Permanent link to this record |
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Author |
Rather, J.A.; De Wael, K. |
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Title |
Fullerene-C60 sensor for ultra-high sensitive detection of bisphenol-A and its treatment by green technology |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
Sensor Actuat B-Chem |
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Volume |
176 |
Issue |
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Pages |
110-117 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Endocrine disruptors (EDCs) are environmental pollutants that, once incorporated into an organism, affect the hormonal balance of humans and various species. Its presence in environment is of great importance in water quality related questions. The proposed method describes the development of an accurate, sensitive and selective sensor for the detection of bisphenol-A (BPA) and its treatment by green technology. A fullerene (C60) fabricated electrochemical sensor was developed for the ultrasensitive detection of BPA. The homemade sensor was characterized by scanning electron microscopy, electrochemical impedance spectroscopy and chronocoulometry. The influence of measuring parameters such as pH and C60 loading on the analytical performance of the sensor was evaluated. Various kinetic parameters such as electron transfer number (n); charge transfer coefficient (α); electrode surface area (A) and diffusion coefficient (D) were also calculated. Under the optimal conditions, the oxidation peak current was linear over the concentration range of 74 nM to 0.23 μM with the detection limit (LOD) of 3.7 nM. The fabricated sensor was successfully applied to the determination of BPA in wastewater samples and it has promising analytical applications for the direct determination of BPA at trace level. |
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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 |
000319867500017 |
Publication Date |
2012-09-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0925-4005 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.401 |
Times cited |
79 |
Open Access |
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Notes |
; The authors are highly thankful for the mobility grant (Non-Europe Postdoc Fellowship) for one of the author (Jahangir Ahmad Rather) supported by the Belgian Federal Science Policy (Belspo) co-funded by the Marie Curie Actions from the European Commission. ; |
Approved |
Most recent IF: 5.401; 2013 IF: 3.840 |
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Call Number |
UA @ admin @ c:irua:101055 |
Serial |
5630 |
| Permanent link to this record |
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Author |
Terzano, R.; Alfeld, M.; Janssens, K.; Vekemans, B.; Schoonjans, T.; Vincze, L.; Tomasi, N.; Pinton, R.; Cesco, S. |
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Title |
Spatially resolved (semi)quantitative determination of iron (Fe) in plants by means of synchrotron micro X-ray fluorescence |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
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Volume |
405 |
Issue |
10 |
Pages |
3341-3350 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Iron (Fe) is an essential element for plant growth and development; hence determining Fe distribution and concentration inside plant organs at the microscopic level is of great relevance to better understand its metabolism and bioavailability through the food chain. Among the available microanalytical techniques, synchrotron mu-XRF methods can provide a powerful and versatile array of analytical tools to study Fe distribution within plant samples. In the last years, the implementation of new algorithms and detection technologies has opened the way to more accurate (semi)quantitative analyses of complex matrices like plant materials. In this paper, for the first time the distribution of Fe within tomato roots has been imaged and quantified by means of confocal mu-XRF and exploiting a recently developed fundamental parameter-based algorithm. With this approach, Fe concentrations ranging from few hundreds of ppb to several hundreds of ppm can be determined at the microscopic level without cutting sections. Furthermore, Fe (semi)quantitative distribution maps were obtained for the first time by using two opposing detectors to collect simultaneously the XRF radiation emerging from both sides of an intact cucumber leaf. |
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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 |
000316338700033 |
Publication Date |
2013-02-07 |
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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 |
1618-2642 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.431 |
Times cited |
27 |
Open Access |
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Notes |
; Research was supported by grants from Italian MIUR (FIRB-Programma “Futuro in Ricerca”) and Free University of Bolzano (TN5046 and TN5056). Synchrotron experiments at HASY-LAB were financially supported by the European Community Research Infrastructure Action under the FP6 “Structuring the European Research Area” Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). Matthias Alfeld receives a Ph.D. fellowship of the Research Foundation-Flanders (FWO). We thank Karen Rickers-Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; |
Approved |
Most recent IF: 3.431; 2013 IF: 3.578 |
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Call Number |
UA @ admin @ c:irua:108261 |
Serial |
5838 |
| Permanent link to this record |
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Author |
Janssens, K.; Alfeld, M.; van der Snickt, G.; de Nolf, W.; Vanmeert, F.; Radepont, M.; Monico, L.; et al. |
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Title |
The use of synchrotron radiation for the characterization of artists' pigments and paintings |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Annual review of analytical chemistry |
Abbreviated Journal |
Annu Rev Anal Chem |
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Volume |
6 |
Issue |
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Pages |
399-425 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
We review methods and recent studies in which macroscopic to (sub)microscopic X-ray beams were used for nondestructive analysis and characterization of pigments, paint microsamples, and/or entire paintings. We discuss the use of portable laboratory- and synchrotron-based instrumentation and describe several variants of X-ray fluorescence (XRF) analysis used for elemental analysis and imaging and combined with X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Macroscopic and microscopic (μ-)XRF variants of this method are suitable for visualizing the elemental distribution of key elements in paint multilayers. Technical innovations such as multielement, large-area XRF detectors have enabled such developments. The use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that take place during natural pigment alteration processes. However, synchrotron-based combinations of μ-XRF, μ-XAS, and μ-XRD are suitable for such 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 |
000323887500019 |
Publication Date |
2013-06-18 |
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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 |
1936-1327 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7.435 |
Times cited |
46 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 7.435; 2013 IF: 7.814 |
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Call Number |
UA @ admin @ c:irua:111315 |
Serial |
5902 |
| Permanent link to this record |
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Author |
Smits, M.; Chan, C. kit; Tytgat, T.; Craeye, B.; Costarramone, N.; Lacombe, S.; Lenaerts, S. |
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Title |
Photocatalytic degradation of soot deposition : self-cleaning effect on titanium dioxide coated cementitious materials |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
222 |
Issue |
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Pages |
411-418 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Diesel soot emissions deteriorate the appearance of architectural building materials by soot fouling. This soot deposition devalue the aesthetic value of the building. A solution to counteract this problem is applying titanium dioxide on building materials. TiO2 can provide air-purifying and self-cleaning properties due to its photocatalytic activity. In literature, photocatalytic soot oxidation is observed on glass or silicon substrates. However, degradation of soot by photocatalysis was not yet investigated on cementitious samples (mortar, concrete) although it is one of the most frequently used building materials. In this study, photocatalytic soot oxidation by means of TiO2 coated cementitious samples is addressed. The soot removal capacity of four types of TiO2 layers, coated on mortar samples, is evaluated by means of two detection methods. The first method is based on colorimetric measurements, while the second method uses digital image processing to calculate the area of soot coverage. The experimental data revealed that cementitious materials coated with commercially available TiO2 exhibited self-cleaning properties as it was found that all coated samples were able to remove soot. The P25 coating gave the best soot degradation performance, while the Eoxolit product showed the slowest soot degradation rate. In addition, gas chromatography measurements in a closed chamber experiment with P25 confirmed that complete mineralization of about 60% of the soot was obtained within 24 hours since CO2 was the sole observed oxidation product. Due to its realistic approach, this study proves that photocatalytic soot removal on TiO2 coated cementitious surfaces is possible in practice, which is an important step towards the practical application of self-cleaning building materials. |
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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 |
000319528900046 |
Publication Date |
2013-03-05 |
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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 |
1385-8947; 1873-3212 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.216 |
Times cited |
43 |
Open Access |
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Notes |
; This work was supported by a PhD grant (M. Smits) from the University of Antwerp, a PhD grant (T. Tytgat) funded by the Institute of Innovation by Science and Technology in Flanders (IWT) and the exchange program Tournesol (Project T2012.05) financed by the Flemish government. ; |
Approved |
Most recent IF: 6.216; 2013 IF: 4.058 |
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Call Number |
UA @ admin @ c:irua:106519 |
Serial |
5979 |
| Permanent link to this record |
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Author |
Verbruggen, S.W.; Keulemans, M.; Martens, J.A.; Lenaerts, S. |
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Title |
Predicting the surface plasmon resonance wavelength of gold-silver alloy nanoparticles |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
117 |
Issue |
37 |
Pages |
19142-19145 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Gold-silver alloy nanoparticles display surface plasmon resonance (SPR) over a broad range of the UV-vis spectrum. We propose a model to predict the SPR wavelength of gold-silver alloy colloids based on the combined effect of alloy composition and particle size. The SPR wavelength is derived from extinction spectra simulated using available experimental dielectric constant data and accounts for particle size by applying Mie theory. Comparison of calculated values with experimental data evidences the accuracy of the model. The new SPR wavelength estimation tool will be of particular interest for developing dedicated bimetallic plasmonic nanostructures. |
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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 |
000330162600042 |
Publication Date |
2013-08-27 |
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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 |
1932-7447; 1932-7455 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.536 |
Times cited |
51 |
Open Access |
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Notes |
; S.W.V. acknowledges the Research Foundation of Flanders (FWO) for financial support. JAM. acknowledges the Flemish government for long-term structural funding (Methusalem). ; |
Approved |
Most recent IF: 4.536; 2013 IF: 4.835 |
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Call Number |
UA @ admin @ c:irua:114837 |
Serial |
5985 |
| Permanent link to this record |
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Author |
Casavola, M.; van Huis, M.A.; Bals, S.; Lambert, K.; Hens, Z.; Vanmaekelbergh, D. |
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Title |
Anisotropic cation exchange in PbSe/CdSe core/shell nanocrystals of different geometry |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
24 |
Issue |
2 |
Pages |
294-302 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We present a study of Cd2+-for-Pb2+ exchange in PbSe nanocrystals (NCs) with cube, star, and rod shapes. Prolonged temperature-activated cation exchange results in PbSe/CdSe heterostructured nanocrystals (HNCs) that preserve their specific overall shape, whereas the PbSe core is strongly faceted with dominance of {111} facets. Hence, cation exchange proceeds while the Se anion lattice is preserved, and well-defined {111}/{111} PbSe/CdSe interfaces develop. Interestingly, by quenching the reaction at different stages of the cation exchange new structures have been isolated, such as coreshell nanorods, CdSe rods that contain one or two separated PbSe dots and fully zinc blende CdSe nanorods. The crystallographically anisotropic cation exchange has been characterized by a combined HRTEM/HAADF-STEM study of heterointerface evolution over reaction time and temperature. Strikingly, Pb and Cd are only intermixed at the PbSe/CdSe interface. We propose a plausible model for the cation exchange based on a layer-by-layer replacement of Pb2+ by Cd2+ enabled by a vacancy-assisted cation migration mechanism. |
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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 |
000299367500008 |
Publication Date |
2011-11-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
9.466 |
Times cited |
136 |
Open Access |
|
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
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Call Number |
UA @ lucian @ c:irua:94211 |
Serial |
124 |
| Permanent link to this record |
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Author |
Narayanan, V.; Lommens, P.; De Buysser, K.; Vanpoucke, D.E.P.; Huehne, R.; Molina, L.; Van Tendeloo, G.; van der Voort, P.; Van Driessche, I. |
| |
Title |
Aqueous CSD approach for the growth of novel, lattice-tuned LaxCe1-xO\delta epitaxial layers |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
| |
Volume |
22 |
Issue |
17 |
Pages |
8476-8483 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Lanthanumcerium oxide (LCO) films were deposited on Ni-5%W substrates by chemical solution deposition (CSD) from water-based precursors. LCO films containing different ratios of lanthanum and cerium ions (from CeO2 to La2Ce2O7) were prepared. The composition of the layers was optimized towards the formation of LCO buffer layers, lattice-matched with the superconducting YBa2Cu3Oy layer, useful for the development of coated conductors. Single, crack-free LCO layers with a thickness of up to 140 nm could be obtained in a single deposition step. The crystallinity and microstructure of these lattice-matched LCO layers were studied by X-ray diffraction techniques, RHEED and SEM. We find that only layers with thickness below 100 nm show a crystalline top surface although both thick and thin layers show good biaxial texture in XRD. On the most promising layers, AFM and (S)TEM were performed to further evaluate their morphology. The overall surface roughness varies between 3.9 and 7.5 nm, while the layers appear much more dense than the frequently used La2Zr2O7 (LZO) systems, showing much smaller nanovoids (12 nm) than the latter system. Their effective buffer layer action was studied using XPS. The thin LCO layers supported the growth of superconducting YBCO deposited using PLD methods. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
| |
Language |
|
Wos |
000302367500044 |
Publication Date |
2012-03-20 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
|
Times cited |
24 |
Open Access |
|
| |
Notes |
Iap |
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ lucian @ c:irua:96960 |
Serial |
148 |
| Permanent link to this record |
| |
|
| |
|
Author |
Palgrave, R.G.; Borisov, P.; Dyer, M.S.; McMitchell, S.R.C.; Darling, G.R.; Claridge, J.B.; Batuk, M.; Tan, H.; Tian, H.; Verbeeck, J.; Hadermann, J.; Rosseinsky, M.J.; |
| |
Title |
Artificial construction of the layered Ruddlesden-Popper manganite La2Sr2Mn3O10 by reflection high energy electron diffraction monitored pulsed laser deposition |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| |
Volume |
134 |
Issue |
18 |
Pages |
7700-7714 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Pulsed laser deposition has been used to artificially construct the n = 3 Ruddlesden Popper structure La2Sr2Mn3O10 in epitaxial thin film form by sequentially layering La1-xSrxMnO3 and SrO unit cells aided by in situ reflection high energy electron diffraction monitoring. The interval deposition technique was used to promote two-dimensional SrO growth. X-ray diffraction and cross-sectional transmission electron microscopy indicated that the trilayer structure had been formed. A site ordering was found to differ from that expected thermodynamically, with the smaller Sr2+ predominantly on the R site due to kinetic trapping of the deposited cation sequence. A dependence of the out-of-plane lattice parameter on growth pressure was interpreted as changing the oxygen content of the films. Magnetic and transport measurements on fully oxygenated films indicated a frustrated magnetic ground state characterized as a spin glass-like magnetic phase with the glass temperature T-g approximate to 34 K. The magnetic frustration has a clear in-plane (ab) magnetic anisotropy, which is maintained up to temperatures of 150 K. Density functional theory calculations suggest competing antiferromagnetic and ferromagnetic long-range orders, which are proposed as the origin of the low-temperature glassy state. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000303696200029 |
Publication Date |
2012-03-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
13.858 |
Times cited |
27 |
Open Access |
|
| |
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 13.858; 2012 IF: 10.677 |
| |
Call Number |
UA @ lucian @ c:irua:98947UA @ admin @ c:irua:98947 |
Serial |
153 |
| Permanent link to this record |
| |
|
| |
|
Author |
Turner, S.; Verbeeck, J.; Ramezanipour, F.; Greedan, J.E.; Van Tendeloo, G.; Botton, G.A. |
| |
Title |
Atomic resolution coordination mapping in Ca2FeCoO5 brownmillerite by spatially resolved electron energy-loss spectroscopy |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| |
Volume |
24 |
Issue |
10 |
Pages |
1904-1909 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Using a combination of high-angle annular dark field scanning transmission electron microscopy and atomically resolved electron energy-loss spectroscopy at high energy resolution in an aberration-corrected electron microscope, we demonstrate the capability of coordination mapping in complex oxides. Brownmillerite compound Ca2FeCoO5, consisting of repetitive octahedral and tetrahedral coordination layers with Fe and Co in a fixed 3+ valency, is selected to demonstrate the principle of atomic resolution coordination mapping. Analysis of the Co-L2,3 and the Fe-L2,3 edges shows small variations in the fine structure that can be specifically attributed to Co/Fe in tetrahedral or in octahedral coordination. Using internal reference spectra, we show that the coordination of the Fe and Co atoms in the compound can be mapped at atomic resolution. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000304237500024 |
Publication Date |
2012-04-25 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
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 |
33 |
Open Access |
|
| |
Notes |
A.M. Abakumov is thanked for fruitful discussions. S.T. gratefully acknowledges the Fund for Scientific Research Flanders (FWO). J.E.G. and GAB. acknowledge the support of the NSERC of Canada through Discovery Grants. The Canadian Centre for Electron Microscopy is a National Facility supported by NSERC and McMaster University and was funded by the Canada Foundation for Innovation and the Ontario Government. Part of this work was supported by funding from the European Research Council under the FP7, ERC Grant N 246791 COUNTATOMS and ERC Starting Grant N 278510 VORTEX. The EMAT microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_; |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
| |
Call Number |
UA @ lucian @ c:irua:98379UA @ admin @ c:irua:98379 |
Serial |
175 |
| Permanent link to this record |
| |
|
| |
|
Author |
Marikutsa, A.; Krivetskiy, V.; Yashina, L.; Rumyantseva, M.; Konstantinova, E.; Ponzoni, A.; Comini, E.; Abakumov, A.; Gaskov, A. |
| |
Title |
Catalytic impact of RuOx clusters to high ammonia sensitivity of tin dioxide |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Sensors and actuators : B : chemical
T2 – 25th Eurosensors Conference, SEP 04-07, 2011, Athens, GREECE |
Abbreviated Journal |
Sensor Actuat B-Chem |
| |
Volume |
175 |
Issue |
|
Pages |
186-193 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
A comparative study of NH3-sensing performance of blank and modified nanocrystal line SnO2 was performed. Tin dioxide modified by ruthenium displayed the highest ammonia sensitivity with a maximum signal at 200 degrees C. The modifier was shown by XPS and EPR to occur in a mixed valence state of oxidized ruthenium distributed between the surface and bulk of tin dioxide nanocrystals. RuOx clustering on SnO2 surface was detected by means of electron microscopy assisted EDX-mapping. The effect of RuOx on tin dioxide interaction with ammonia was studied by temperature-programmed NH3 desorption, simultaneous Kelvin probe and DC-resistance measurements, EPR spectroscopy and analyses of the gas-solid interaction products. The modifier was shown to promote the materials reactivity to NH3 due to the catalytic activity of RuOx. The interaction with ammonia resulted in dipoles formation on the oxide surface along with reducing the grains net surface charge, established from the electron affinity increase and resistance decrease during NH3 exposure. The RuOx-catalyzed gas-solid interaction was deduced to proceed deeper than in the case of non-modified SnO2 and to yield nitrogen oxides (e.g. NO2), as was suggested by the oxidative character of gaseous products of NH3 interaction with RuOx-modified tin dioxide at 200 degrees C. (C) 2012 Elsevier B.V. All rights reserved. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
| |
Language |
|
Wos |
000312358700033 |
Publication Date |
2012-06-19 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
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 |
20 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 5.401; 2012 IF: 3.535 |
| |
Call Number |
UA @ lucian @ c:irua:105985 |
Serial |
293 |
| Permanent link to this record |
| |
|
| |
|
Author |
Adamson, P.; Hadermann, J.; Smura, C.F.; Rutt, O.J.; Hyett, G.; Free, D.G.; Clarke, S.J. |
| |
Title |
Competing magnetic structures and the evolution of copper ion/vacancy ordering with composition in the manganite oxide chalcogenides Sr2MnO2Cu1.5(S1-xSex)2 |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| |
Volume |
24 |
Issue |
14 |
Pages |
2802-2816 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The series Sr2MnO2Cu1.5(S1-xSex)(2) (0 <= x <= 1) contains mixed-valent Mn ions (Mn2+/Mn3+) in MnO2 sheets which are separated by copper-deficient antifluorite-type Cu(2-delta)Ch(2) layers with delta similar to 0.5. The compounds crystallize in the structure type first described for Sr2Mn3Sb2O2 and are described in the I4/mmm space group at ambient temperatures. Below about 250 K, ordering between Cu+ ions and tetrahedral vacancies occurs which is long-range and close to complete in the sulfide-containing end member of the series Sr2MnO2Cu1.5S2 but which occurs over shorter length scales as the selenide content increases. The superstructure is an orthorhombic 2 root 2a x root 2a x c expansion in Ibam of the room temperature cell. For x > 0.3 there are no superstructure reflections evident in the X-ray or neutron diffraction patterns, and the I4/mmm description is valid for the average structure at all temperatures. However, in the pure selenide end member, Sr2MnO2Cu1.5Se2, diffuse scattering in electron diffractograms and modulation in high resolution lattice image profiles may arise from short-range Cu/vacancy order. All members of the series exhibit long-range magnetic order. In the sulfide-rich end member and in compounds with x < 0.1 in the formula Sr2MnO2Cu1.5(S1-xSex)(2), which show well developed superstructures due to long-range Cu/vacancy order, the magnetic structure has a (1/4 1/4 0) propagation vector in which ferromagnetic zigzag chains of Mn moments in the MnO2 sheets are coupled antiferromagnetically in an arrangement described as the CE-type magnetic structure and found in many mixed-valent perovskite and Ruddlesden-Popper type oxide manganites. In these cases the magnetic cell is an a x 2b x c expansion of the low temperature Ibam structural cell. For x >= 0.2 in the formula Sr2MnO2Cu1.5(S1-xSex)(2) the magnetic structure has a (0 0 0) propagation vector and is similar to the A-type structure, also commonly adopted by some perovskite-related manganites, in which the Mn moments in the MnO2 sheets are coupled ferromagnetically and long-range antiferromagnetic order results from antiferromagnetic coupling between planes. In the region of the transition between the two different structural and magnetic long-range ordering schemes (0.1 < x < 0.2) the two magnetic structures coexist in the same sample. The evolution of the competition between magnetic ordering schemes and the length scale of the structural order with composition in Sr2MnO2Cu1.5(S1-xSex)(2) suggest that the changes in magnetic and structural order are related consequences of the introduction of chemical disorder. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000306674200024 |
Publication Date |
2012-06-20 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
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 |
11 |
Open Access |
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
| |
Call Number |
UA @ lucian @ c:irua:100839 |
Serial |
435 |
| Permanent link to this record |
| |
|
| |
|
Author |
de Oliveira, E.L.; Albuquerque, E.L.; de Sousa, J.S.; Farias, G.A.; Peeters, F.M. |
| |
Title |
Configuration-interaction excitonic absorption in small Si/Ge and Ge/Si core/shell nanocrystals |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
116 |
Issue |
7 |
Pages |
4399-4407 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
The excitonic properties of Si(core)/Ge(shell) and Ge(core)/Si(shell) nanocrystals (NC's) with diameters of similar to 1.9 nm are investigated using a combination density functional ab initio method to obtain the single particle wave functions and a configuration interaction method to compute the exciton fine structure and absorption coefficient. These core/shell structures exhibit type II confinement, which is more pronounced for the Si/Ge NC as a consequence of strain. The absorption coefficients of these NC's exhibit a single dominant peak, which has a much larger oscillator strength than the multipeaks found for pure Si and Ge NC's. The exciton lifetime in Si, Ge, and Ge/Si shows a small i:emperature dependence in the range 10-300 K, whereas in Si/Ge, the exciton lifetime decreases more than an order of magnitude in the same temperature range. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000301156500007 |
Publication Date |
2012-01-04 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.536 |
Times cited |
44 |
Open Access |
|
| |
Notes |
; The authors acknowledge financial support from CNPq and the bilateral program between Flanders and Brazil and the Belgian Science Foundation (IAP). ; |
Approved |
Most recent IF: 4.536; 2012 IF: 4.814 |
| |
Call Number |
UA @ lucian @ c:irua:113045 |
Serial |
482 |
| Permanent link to this record |
| |
|
| |
|
Author |
Wee, L.H.; Wiktor, C.; Turner, S.; Vanderlinden, W.; Janssens, N.; Bajpe, S.R.; Houthoofd, K.; Van Tendeloo, G.; De Feyter, S.; Kirschhock, C.E.A.; Martens, J.A.; |
| |
Title |
Copper benzene tricarboxylate metal-organic framework with wide permanent mesopores stabilized by keggin polyoxometallate ions |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| |
Volume |
134 |
Issue |
26 |
Pages |
10911-10919 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Porous solids with organized multiple porosity are of scientific and technological importance for broadening the application range from traditional areas of catalysis and adsorption/separation to drug release and biomedical imaging. Synthesis of crystalline porous materials offering a network of uniform micro- and mesopores remains a major scientific challenge. One strategy is based on variation of synthesis parameters of microporous networks, such as, for example, zeolites or metal organic frameworks (MOFs). Here, we show the rational development of an hierarchical variant of the microporous cubic Cu-3(BTC)(2) (BTC = 1,3,5-benzenetricarboxylate) HKUST-1 MOF having strictly repetitive S inn wide mesopores separated by uniform microporous walls in a single crystal structure. This new material coined COK-15 (COK = Centrum voor Oppervlaktechemie en Katalyse) was synthesized via a dual-templating approach. Stability was enhanced by Keggin type phosphotungstate (HPW) systematically occluded in the cavities constituting the walls between the mesopores. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000305863900037 |
Publication Date |
2012-06-06 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
13.858 |
Times cited |
83 |
Open Access |
|
| |
Notes |
Iap; Fwo |
Approved |
Most recent IF: 13.858; 2012 IF: 10.677 |
| |
Call Number |
UA @ lucian @ c:irua:100330 |
Serial |
514 |
| Permanent link to this record |
| |
|
| |
|
Author |
Nagy, N.V.; Van Doorslaer, S.; Szabó-Plánka, T.; Van Rompaey, S.; Hamza, A.; Fülöp, F.; Tóth, G.K.; Rockenbauer, A. |
| |
Title |
Copper(II)-binding ability of stereoisomeric cis- and trans-2-aminocyclohexanecarboxylic acidl-phenylalanine dipeptides : a combined CW/pulsed EPR and DFT study |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
| |
Volume |
51 |
Issue |
3 |
Pages |
1386-1399 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
With the aim of an improved understanding of the metal-complexation properties of alicyclic β-amino acid stereoisomers, and their peptides, the complex equilibria and modes of coordination with copper(II) of l-phenylalanine (F) derivatives of cis/trans-2-aminocyclohexanecarboxylic acid (c/tACHC), i.e. the dipeptides F-c/tACHC and c/tACHC-F, were investigated by a combination of CW and pulsed EPR methods. For the interpretation of the experimental data, DFT quantum-chemical calculations were carried out. Simulation of a pH-dependent series of room-temperature CW-EPR spectra revealed the presence of EPR-active complexes ([Cu(aqua)]2+, [CuL]+, [CuLH1], [CuLH2]−, and [CuL2H1]−), and an EPR-inactive species ([Cu2L2H3]−) in aqueous solutions for all studied cases. [CuLH]2+ was included in the equilibrium model for the c/tACHC-Fcopper(II) systems, and [CuL2], together with two coordination isomers of [CuL2H1]−, were also identified in the F-tACHCcopper(II) system. Comparison of the complexation properties of the diastereomeric ligand pair F-(1S,2R)-ACHC and F-(1R,2S)-ACHC did not reveal significant differences. Considerably lower formation constants were obtained for the trans than for the cis isomers for both the F-c/tACHC and the c/tACHC-F pairs in the case of [CuLH1] involving tridentate coordination by the amino, the deprotonated peptide, and the carboxylate groups. A detailed structural analysis by pulsed EPR methods and DFT calculations indicated that there was no significant destabilization for the complexes of the trans isomers. The lower stability of their complexes was explained by the limitation that only the conformer with donor groups in equatorialequatorial ring positions can bind to copper(II), whereas both equatorial-axial conformers of the cis isomers are capable of binding. From a consideration of the proton couplings obtained with X-band 1H HYSCORE, 2H exchange experiments, and DFT, the thermodynamically most stable cyclohexane ring conformer was assigned for all four [CuLH1] complexes. For the F-cACHC case, the conformer did not match the most stable conformer of the free ligand. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
| |
Language |
|
Wos |
000300474700029 |
Publication Date |
2012-01-06 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.857 |
Times cited |
18 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
| |
Call Number |
UA @ lucian @ c:irua:96729 |
Serial |
515 |
| Permanent link to this record |
| |
|
| |
|
Author |
Hadermann, J.; Abakumov, A.; Van Rompaey, S.; Perkisas, T.; Filinchuk, Y.; Van Tendeloo, G. |
| |
Title |
Crystal structure of a lightweight borohydride from submicrometer crystallites by precession electron diffraction |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| |
Volume |
24 |
Issue |
17 |
Pages |
3401-3405 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
We demonstrate that precession electron diffraction at low-dose conditions can be successfully applied for structure analysis of extremely electron-beam-sensitive materials. Using LiBH4 as a test material, complete structural information, including the location of the H atoms, was obtained from submicrometer-sized crystallites. This demonstrates for the first time that, where conventional transmission electron microscopy techniques fail, quantitative precession electron diffraction can provide structural information from submicrometer particles of such extremely electron-beam-sensitive materials as complex lightweight hydrides. We expect the precession electron diffraction technique to be a useful tool for nanoscale investigations of thermally unstable lightweight hydrogen-storage materials. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000308833400012 |
Publication Date |
2012-08-01 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
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 |
17 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
| |
Call Number |
UA @ lucian @ c:irua:101845 |
Serial |
567 |
| Permanent link to this record |
| |
|
| |
|
Author |
Neyts, E.C.; Thijsse, B.J.; Mees, M.J.; Bal, K.M.; Pourtois, G. |
| |
Title |
Establishing uniform acceptance in force biased Monte Carlo simulations |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of chemical theory and computation |
Abbreviated Journal |
J Chem Theory Comput |
| |
Volume |
8 |
Issue |
6 |
Pages |
1865-1869 |
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
Uniform acceptance force biased Monte Carlo (UFMC) simulations have previously been shown to be a powerful tool to simulate atomic scale processes, enabling one to follow the dynamical path during the simulation. In this contribution, we present a simple proof to demonstrate that this uniform acceptance still complies with the condition of detailed balance, on the condition that the characteristic parameter lambda = 1/2 and that the maximum allowed step size is chosen to be sufficiently small. Furthermore, the relation to Metropolis Monte Carlo (MMC) is also established, and it is shown that UFMC reduces to MMC by choosing the characteristic parameter lambda = 0 [Rao, M. et al. Mol. Phys. 1979, 37, 1773]. Finally, a simple example compares the UFMC and MMC methods. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000305092400002 |
Publication Date |
2012-05-16 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1549-9618;1549-9626; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.245 |
Times cited |
20 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 5.245; 2012 IF: 5.389 |
| |
Call Number |
UA @ lucian @ c:irua:99090 |
Serial |
1082 |
| Permanent link to this record |
| |
|
| |
|
Author |
Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Rozova, M.G.; Sarakinou, E.; Antipov, E.V. |
| |
Title |
Expanding the Ruddlesden-Popper manganite family : the n=3 La3.2Ba0.8Mn3O10 Member |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
| |
Volume |
51 |
Issue |
21 |
Pages |
11487-11492 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
La3.2Ba0.8Mn3O10, a representative of the rare n = 3 members of the Ruddlesden-Popper manganites A(n+1)Mn(n)O(3n+1), was synthesized in an evacuated sealed silica tube. Its crystal structure was refined from a combination of powder X-ray diffraction (PXD) and precession electron diffraction (PED) data, with the rotations of the MnO6 octahedra described within the symmetry-adapted mode approach (space group Cccm, a = 29.068(1) angstrom, b = 5.5504(5) angstrom, c = 5.5412(5) angstrom; PXD RF = 0.053, RP = 0.026; PED RF = 0.248). The perovskite block in La3.2Ba0.8Mn3O10 features an octahedral tilting distortion with out-of-phase rotations of the Mn06 octahedra according to the (Phi,Phi,0)(Phi,Phi,0) mode, observed for the first time in the n = 3 Ruddlesden-Popper structures. The Mn06 octahedra demonstrate a noticeable deformation with the elongation of two apical Mn-O bonds due to the Jahn-Teller effect in the Mn3+ cations. The relationships between the octahedral tilting distortion, the ionic radii of the cations at the A- and B-positions, and the mismatch between the perovslcite and rock-salt blocks of the Ruddlesden-Popper structure are discussed. At low temperatures, La3.2Ba0.8Mn3O10 reveals a sizable remnant magnetization of about 1.3 mu(B)/Mn at 2K, and shows signatures of spin freezing below 150 K. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
| |
Language |
|
Wos |
000313220200036 |
Publication Date |
2012-10-17 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.857 |
Times cited |
2 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
| |
Call Number |
UA @ lucian @ c:irua:110121 |
Serial |
1133 |
| Permanent link to this record |
| |
|
| |
|
Author |
Sivek, J.; Leenaerts, O.; Partoens, B.; Peeters, F.M. |
| |
Title |
First-principles investigation of bilayer fluorographene |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
116 |
Issue |
36 |
Pages |
19240-19245 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
Ab initio calculations within the density functional theory formalism are performed to investigate the stability and electronic properties of fluorinated bilayer graphene (bilayer fluorographene). A comparison is made to previously investigated graphane, bilayer graphane, and fluorographene. Bilayer fluorographene is found to be a much more stable material than bilayer graphane. Its electronic band structure is similar to that of monolayer fluorographene, but its electronic band gap is significantly larger (about 1 eV). We also calculate the effective masses around the Gamma-point for fluorographene and bilayer fluorographene and find that they are isotropic, in contrast to earlier reports. Furthermore, it is found that bilayer fluorographene is almost as strong as graphene, as its 2D Young's modulus is approximately 300 N m(-1). |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000308631300022 |
Publication Date |
2012-08-21 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.536 |
Times cited |
39 |
Open Access |
|
| |
Notes |
; This work is supported by the ESF-Eurocores program EuroGRAPHENE (project CONERAN) and the Flemish Science Foundation (FWO-V1). ; |
Approved |
Most recent IF: 4.536; 2012 IF: 4.814 |
| |
Call Number |
UA @ lucian @ c:irua:101842 |
Serial |
1211 |
| Permanent link to this record |
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|
| |
|
Author |
Maignan, A.; Martin, C.; Singh, K.; Simon, C.; Lebedev, O.I.; Turner, S. |
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Title |
From spin induced ferroelectricity to dipolar glasses : spinel chromites and mixed delafossites |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| |
Volume |
195 |
Issue |
|
Pages |
41-49 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Magnetoelectric multiferroics showing coupling between polarization and magnetic order are attracting much attention. For instance, they could be used in memory devices. Metal-transition oxides are provided several examples of inorganic magnetoelectric multiferroics. In the present short review, spinel and delafossite chromites are described. For the former, an electric polarization is evidenced in the ferrimagnetic state for ACr2O4 polycrystalline samples (A=Ni, Fe, Co). The presence of a JahnTeller cation such as Ni2+ at the A site is shown to yield larger polarization values. In the delafossites, substitution by V3+ at the Cr or Fe site in CuCrO2 (CuFeO2) suppresses the complex antiferromagnetic structure at the benefit of a spin glass state. The presence of cation disorder, probed by transmission electron microscopy, favors relaxor-like ferroelectricity. The results on the ferroelectricity of ferrimagnets and insulating spin glasses demonstrate that, in this research field, transition-metal oxides are worth to be studied. |
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Address |
|
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
London |
Editor |
|
| |
Language |
|
Wos |
000309783600006 |
Publication Date |
2012-02-09 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.299 |
Times cited |
27 |
Open Access |
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.299; 2012 IF: 2.040 |
| |
Call Number |
UA @ lucian @ c:irua:101219 |
Serial |
1286 |
| Permanent link to this record |
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|
| |
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Author |
Navío, C.; Vallejos, S.; Stoycheva, T.; Llobet, E.; Correig, X.; Snyders, R.; Blackman, C.; Umek, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; |
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Title |
Gold clusters on WO3 nanoneedles grown via AACVD : XPS and TEM studies |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Materials chemistry and physics |
Abbreviated Journal |
Mater Chem Phys |
| |
Volume |
134 |
Issue |
2/3 |
Pages |
809-813 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol assisted chemical vapor deposition (AACVD) and characterized them using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM shows that both the needles and the gold particles are crystalline. XPS indicates the presence of oxygen vacancies, i.e. the films are WO3−x, and hence the deposited material is composed of semiconducting nanostructures and that the interaction between the gold particles and the WO3 needles surface is weak. The synthesis of semiconducting tungsten oxide nanostructures decorated with metal particles represents an important step towards the development of sensing devices with optimal properties. |
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Address |
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Corporate Author |
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Thesis |
|
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Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
| |
Language |
|
Wos |
000305918200038 |
Publication Date |
2012-04-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0254-0584; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.084 |
Times cited |
52 |
Open Access |
|
| |
Notes |
Iap |
Approved |
Most recent IF: 2.084; 2012 IF: 2.072 |
| |
Call Number |
UA @ lucian @ c:irua:97705 |
Serial |
1356 |
| Permanent link to this record |
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|
| |
|
Author |
Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Herber, R.H.; Nowik, I.; Hodges, J.P.; Dachraoui, W.; Hadermann, J.; Greenblatt, M.; |
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Title |
High magnetic ordering temperature in the perovskites Sr4-xLaxFe3ReO12 (x=0.0, 1.0, 2.0) |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| |
Volume |
194 |
Issue |
|
Pages |
48-58 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
A series of perovskites Sr4−xLaxFe3ReO12 (x=0.0, 1.0, 2.0) has been prepared by wet chemistry methods. The structure analyses by powder X-ray and neutron diffraction and electron microscopy show that these compounds adopt simple perovskite structures without cation ordering over the B sites: tetragonal (I4/mcm) for x=0.0 and 1.0 and orthorhombic (Pbmn) for x=2.0. The oxidation states of the cations in the compound with x=0.0 appear to be Fe3+/4+ and Re7+ and decrease for both with La substitution as evidenced by X-ray absorption spectroscopy. All the compounds are antiferromagnetically ordered above room temperature, as demonstrated by Mössbauer spectroscopy and the magnetic structures, which were determined by powder neutron diffraction. The substitution of Sr by La strongly affects the magnetic properties with an increase of TN up to ∼750 K. |
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Address |
|
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
| |
Language |
|
Wos |
000308896400009 |
Publication Date |
2012-07-02 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.299 |
Times cited |
9 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.299; 2012 IF: 2.040 |
| |
Call Number |
UA @ lucian @ c:irua:101220 |
Serial |
1435 |
| Permanent link to this record |
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|
| |
|
Author |
Khalilov, U.; Pourtois, G.; van Duin, A.C.T.; Neyts, E.C. |
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Title |
Hyperthermal oxidation of Si(100)2x1 surfaces : effect of growth temperature |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
116 |
Issue |
15 |
Pages |
8649-8656 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
Using reactive molecular dynamics simulations based on the ReaxFF potential, we studied the growth mechanism of ultrathin silica (SiO2) layers during hyperthermal oxidation as a function of temperature in the range 100-1300 K. Oxidation of Si(100){2 x 1} surfaces by both atomic and molecular oxygen was investigated for hyperthermal impact energies in the range of 1 to 5 eV. Two different growth mechanisms are found, corresponding to a low temperature oxidation and a high temperature one. The transition temperature between these mechanisms is estimated to be about 700 K. Also, the initial step of the Si oxidation process is analyzed in detail. Where possible, we validated our results with experimental and ab initio data, and good agreement was obtained. This study is important for the fabrication of silica-based devices in the micro- and nanoelectronics industry and, more specifically, for the fabrication of metal oxide semiconductor devices. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000302924900035 |
Publication Date |
2012-03-26 |
| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.536 |
Times cited |
32 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.536; 2012 IF: 4.814 |
| |
Call Number |
UA @ lucian @ c:irua:98259 |
Serial |
1542 |
| Permanent link to this record |
| |
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| |
|
Author |
Aerts, R.; Martens, T.; Bogaerts, A. |
| |
Title |
Influence of vibrational states on CO2 splitting by dielectric barrier discharges |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| |
Volume |
116 |
Issue |
44 |
Pages |
23257-23273 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
In this paper, the splitting of CO2 in a pulsed plasma system, such as a dielectric barrier discharge (DBD), is evaluated from a chemical point of view by means of numerical modeling. For this purpose, a chemical reaction set of CO2 in an atmospheric pressure plasma is developed, including the vibrational states of CO2, O2, and CO. The simulated pulses are matched to the conditions of a filament (or microdischarge) and repeated with intervals of 1 μs. The influence of vibrationally excited CO2 as well as other neutral species, ions, and electrons on the CO2 splitting is discussed. Our calculations predict that the electrons have the largest contribution to the CO2 splitting at the conditions under study, by electron impact dissociation. The contribution of vibrationally excited CO2 levels in the splitting of CO2 is found be 6.4%, when only considering one microdischarge pulse and its afterglow, but it can be much higher for consecutive discharge pulses, as is typical for a filamentary DBD, when the interpulse time is short enough and accumulation effects in the vibrationally excited CO2 densities can occur. |
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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 |
000310769300012 |
Publication Date |
2012-10-19 |
| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.536 |
Times cited |
112 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 4.536; 2012 IF: 4.814 |
| |
Call Number |
UA @ lucian @ c:irua:101764 |
Serial |
1659 |
| Permanent link to this record |
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| |
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Author |
Neyts, E.C.; van Duin, A.C.T.; Bogaerts, A. |
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Title |
Insights in the plasma-assisted growth of carbon nanotubes through atomic scale simulations : effect of electric field |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| |
Volume |
134 |
Issue |
2 |
Pages |
1256-1260 |
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
Carbon nanotubes (CNTs) are nowadays routinely grown in a thermal CVD setup. State-of-the-art plasma-enhanced CVD (PECVD) growth, however, offers advantages over thermal CVD. A lower growth temperature and the growth of aligned freestanding single-walled CNTs (SWNTs) makes the technique very attractive. The atomic scale growth mechanisms of PECVD CNT growth, however, remain currently entirely unexplored. In this contribution, we employed molecular dynamics simulations to focus on the effect of applying an electric field on the SWNT growth process, as one of the effects coming into play in PECVD. Using sufficiently strong fields results in (a) alignment of the growing SWNTs, (b) a better ordering of the carbon network, and (c) a higher growth rate relative to thermal growth rate. We suggest that these effects are due to the small charge transfer occurring in the Ni/C system. These simulations constitute the first study of PECVD growth of SWNTs on the atomic level. |
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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 |
000301084300086 |
Publication Date |
2011-11-30 |
| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
13.858 |
Times cited |
56 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 13.858; 2012 IF: 10.677 |
| |
Call Number |
UA @ lucian @ c:irua:97163 |
Serial |
1673 |
| Permanent link to this record |
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| |
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Author |
Dachraoui, W.; Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Batuk, D.; Glazyrin, K.; McCammon, C.; Dubrovinsky, L.; Van Tendeloo, G. |
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Title |
Local oxygen-vacancy ordering and twinned octahedral tilting pattern in the Bi0.81Pb0.19FeO2.905 cubic perovskite |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| |
Volume |
24 |
Issue |
7 |
Pages |
1378-1385 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The structure of Bi0.81Pb0.19FeO2.905 was investigated on different length scales using a combination of electron diffraction, high-resolution scanning transmission electron microscopy, synchrotron X-ray powder diffraction, and Mössbauer spectroscopy. In the 80300 K temperature range, the average crystal structure of Bi0.81Pb0.19FeO2.905 is a cubic Pm3̅m perovskite with a = 3.95368(3) Å at T = 300 K. The (Pb2+, Bi3+) cations and O2 anions are randomly displaced along the 110 cubic directions, indicating the steric activity of the lone pair on the Pb2+ and Bi3+ cations and a tilting distortion of the perovskite framework. The charge imbalance induced by the heterovalent Bi3+ → Pb2+ substitution is compensated by the formation of oxygen vacancies preserving the trivalent state of the Fe cations. On a short scale, oxygen vacancies are located in anion-deficient (FeO1.25) layers that are approximately 6 perovskite unit cells apart and transform every sixth layer of the FeO6 octahedra into a layer with a 1:1 mixture of corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids. The anion-deficient layers act as twin planes for the octahedral tilting pattern of adjacent perovskite blocks. They effectively randomize the octahedral tilting and prevent the cooperative distortion of the perovskite framework. The disorder in the anion sublattice impedes cooperative interactions of the local dipoles induced by the off-center displacements of the Pb and Bi cations. Magnetic susceptibility measurements evidence the antiferromagnetic ordering in Bi0.81Pb0.19FeO2.905 at low temperatures. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| |
Language |
|
Wos |
000302487500018 |
Publication Date |
2012-03-13 |
| |
Series Editor |
|
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 |
27 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
| |
Call Number |
UA @ lucian @ c:irua:97389 |
Serial |
1829 |
| Permanent link to this record |
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| |
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Author |
Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Hadermann, J.; Hodges, J.P.; Herber, R.H.; Nowik, I.; Greenblatt, M.; |
| |
Title |
Magnetic and structural studies of the multifunctional material SrFe0.75Mo0.25O3-\text{\textgreek{d}} |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
| |
Volume |
51 |
Issue |
22 |
Pages |
12273-12280 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
SrFe0.75Mo0.25O3-delta has been recently discovered as an extremely efficient electrode for intermediate temperature solid oxide fuel cells (IT-SOFCs). We have performed structural and magnetic studies to fully characterize this multifunctional material. We have observed by powder neutron diffraction (PND) and transmission electron microscopy (TEM) that its crystal symmetry is better explained with a tetragonal symmetry (I4/mcm space group) than with the previously reported orthorhombic symmetry (Pnma space group). The temperature dependent magnetic properties indicate an exceptionally high magnetic ordering temperature (T-N similar to 750 K), well above room temperature. The ordered magnetic structure at low temperature was determined by PND to be an antiferromagnetic coupling of the Fe cations. Mossbauer spectroscopy corroborated the PND results. A detailed study, with X-ray absorption spectroscopy (XAS), in agreement with the Mossbauer results, confirmed the formal oxidation states of the cations to be mixed valence Fe3+/4+ and Mo6+. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
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Language |
|
Wos |
000311173700024 |
Publication Date |
2012-10-26 |
| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.857 |
Times cited |
12 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
| |
Call Number |
UA @ lucian @ c:irua:105142 |
Serial |
1862 |
| Permanent link to this record |
