Records |
Author |
Skaltsas, T.; Ke, X.; Bittencourt, C.; Tagmatarchis, N. |
Title |
Ultrasonication induces oxygenated species and defects onto exfoliated graphene |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
117 |
Issue |
44 |
Pages |
23272-23278 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The effect of ultrasonication parameters, such as time and power applied, to exfoliate graphite in o-dichlorobenzene (o-DCB) and N-methyl-1,2-pyrrolidone (NMP) was examined. It was found that the concentration of graphene was higher in o-DCB, while its dispersibility was increased when sonication was applied for a longer period and/or at higher power. However, spectroscopic examination by X-ray photoelectron spectroscopy (XPS) revealed that ultrasonication causes defects and induces oxygen functional groups in the form of carboxylic acids and ethers/epoxides onto the graphene lattice. Additional proof for the latter arose from Raman, IR, and thermogravimetry studies. The carboxylic acids and ethers/epoxides onto exfoliated graphene were derived from air during ultrasonication and found independent of the solvent used for the exfoliation and the power and/or time ultrasonication applied. Quantitative evaluation of the amount of oxygenated species present on exfoliated graphene as performed by high-resolution XPS revealed that the relative oxygen percentage was higher when exfoliation was performed in NMP. Finally, the sonication time and/or power affected the oxygen content on exfoliated graphene, since extended ultrasonication resulted in a decrease in the oxygen content on exfoliated graphene, with a simultaneous increase of defected sp(3) carbon atoms. |
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 |
000326845400090 |
Publication Date |
2013-10-03 |
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 |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
65 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.536; 2013 IF: 4.835 |
Call Number |
UA @ lucian @ c:irua:112710 |
Serial |
3797 |
Permanent link to this record |
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Author |
Verbruggen, S.W.; Keulemans, M.; Martens, J.A.; Lenaerts, S. |
Title |
Predicting the surface plasmon resonance wavelength of gold-silver alloy nanoparticles |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
117 |
Issue |
37 |
Pages |
19142-19145 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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. |
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 |
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 |
1932-7447; 1932-7455 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
51 |
Open Access |
|
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 |
Call Number |
UA @ admin @ c:irua:114837 |
Serial |
5985 |
Permanent link to this record |
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Author |
Saniz, R.; Xu, Y.; Matsubara, M.; Amini, M.N.; Dixit, H.; Lamoen, D.; Partoens, B. |
Title |
A simplified approach to the band gap correction of defect formation energies : Al, Ga, and In-doped ZnO |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
The journal of physics and chemistry of solids |
Abbreviated Journal |
J Phys Chem Solids |
Volume |
74 |
Issue |
1 |
Pages |
45-50 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
The calculation of defect levels in semiconductors within a density functional theory approach suffers greatly from the band gap problem. We propose a band gap correction scheme that is based on the separation of energy differences in electron addition and relaxation energies. We show that it can predict defect levels with a reasonable accuracy, particularly in the case of defects with conduction band character, and yet is simple and computationally economical. We apply this method to ZnO doped with group III elements (Al, Ga, In). As expected from experiment, the results indicate that Zn substitutional doping is preferred over interstitial doping in Al, Ga, and In-doped ZnO, under both zinc-rich and oxygen-rich conditions. Further, all three dopants act as shallow donors, with the +1 charge state having the most advantageous formation energy. Also, doping effects on the electronic structure of ZnO are sufficiently mild so as to affect little the fundamental band gap and lowest conduction bands dispersion, which secures their n-type transparent conducting behavior. A comparison with the extrapolation method based on LDA+U calculations and with the HeydScuseriaErnzerhof hybrid functional (HSE) shows the reliability of the proposed scheme in predicting the thermodynamic transition levels in shallow donor systems. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000311062500009 |
Publication Date |
2012-08-10 |
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 |
0022-3697; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.059 |
Times cited |
36 |
Open Access |
|
Notes |
Fwo; Bof-Nio |
Approved |
Most recent IF: 2.059; 2013 IF: 1.594 |
Call Number |
UA @ lucian @ c:irua:101782 |
Serial |
3004 |
Permanent link to this record |
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Author |
Godoi, R.H.M.; Godoi, A.F.L.; Gonçalves jr., S.J.; Paralovo, S.L.; Borillo, G.C.; Gregório Barbosa, C.G.; Arantes, M.G.; Rosário Filho, N.A.; Grassi, M.T.; Yamamoto, C.I.; Potgieter-Vermaak, S.; Rotondo, G.G.; De Wael, K.; Van Grieken, R. |
Title |
Healthy environment : indoor air quality of Brazilian elementary schools nearby petrochemical industry |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
The science of the total environment |
Abbreviated Journal |
Sci Total Environ |
Volume |
463 |
Issue |
|
Pages |
639-646 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The mitigation of pollution released to the environment originating fromthe industrial sector has been the aimof all policy-makers and its importance is evident if the adverse health effects on the world population are considered. Although this concern is controversial, petroleum refinery has been linked to some adverse health effects for people living nearby. Apart from home, school is the most important indoor environment for children and there is increasing concern about the school environment and its impact on health, also in developing countries where the prevalence of pollution is higher. As most of the children spend more than 40% of their time in schools, it is critical to evaluate the pollution level in such environment. In the metropolitan region of Curitiba, South Brazil, five schools nearby industries and highways with high density traffic, were selected to characterize the aerosol and gaseous compounds indoor and outdoor of the classrooms, during 20092011. Size segregated aerosol samples were collected for analyses of bulk and single particle elemental profiles. They were analyzed by electron probe X-ray micro-analysis (EPXMA), and by energy-dispersive X-ray fluorescence (EDXRF), to investigate the elemental composition of individual particles and bulk samples. The concentrations of benzene, toluene, ethylbenzene, and xylene (BTEX); NO2; SO2; acetic acid; and formic acid were assessed indoor and outdoor using passive diffusion tubes. BTEX were analyzed by GCMS and other collected gasses by ion chromatography. Individual exposition of BTEX was assessed by personal passive diffusion tubes. Results are interpreted separately and as a whole with the specific aim of identifying compounds that could affect the health of the scholars. In view of the chemical composition and size distribution of the aerosol particles, local deposition efficiencies in the children's respiratory systems were calculated, revealing the deposition of particles at extrathoracic, tracheobronchial and pulmonary levels. |
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 |
000325831200072 |
Publication Date |
2013-07-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0048-9697 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.9 |
Times cited |
22 |
Open Access |
|
Notes |
; We would like to thank Araucaria Foundation and the National Council for Scientific and Technological Development (CNPq) who supported the funding and promoted the development of this study. ; |
Approved |
Most recent IF: 4.9; 2013 IF: 3.163 |
Call Number |
UA @ admin @ c:irua:108954 |
Serial |
5637 |
Permanent link to this record |
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Author |
Hellar-Kihampa, H.; De Wael, K.; Lugwisha, E.; Govindan, M.; Covaci, A.; Van Grieken, R. |
Title |
Spatial monitoring of organohalogen compounds in surface water and sediments of a rural-urban river basin in Tanzania |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
The science of the total environment |
Abbreviated Journal |
Sci Total Environ |
Volume |
447 |
Issue |
|
Pages |
186-197 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
Abstract |
The presence of persistent organic pollutants in Tanzanian environment is not well monitored despite the existing pollution potential from a number of sources. In this study, we investigated for the first time, the concentration profiles of different organohalogen compounds such as organochlorine pesticide residues (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in environmental samples (water and sediments) from the Pangani river basin (PRB). The PRB is one of the largest drainage basins in Tanzania, with its watershed exposed to multiple input sources of trace organic contaminants. Surface water and sediments were sampled from 12 representative stations of diverse characteristics and land-use practices, in three distinct seasons, and extracted by liquidliquid and Soxhlet extraction methods, respectively. Water samples were analyzed by GC-ECD for OCPs only, while sediment samples were analyzed for OCPs, PCBs and PBDEs by GC/MS. Seven compounds, dominated by HCH isomers (5104460 pg/L) and DDT analogs (1601460 pg/L),were detected in the water samples. These concentrations are far below the WHO guidelines for drinking water quality. A total of 42 compounds (8 OCPs, 28 PCB congeners and 6 PBDE congeners) were detected in the sediment samples. Their respective total concentration ranges were 24510,230; 35711,000 and 382175 pg/g dry weight. The spatial distribution patterns and Hierarchical Cluster Analysis reflected the impact of historical agricultural usage in sugarcane plantations (OCPs), and urbanization (PCBs and PBDEs). Risk assessment using sediment quality guidelines indicated no ecotoxicological risks. The results we have found provide preliminary data on levels of the organic contaminants in Pangani river basin as a new insight on the environmental quality of the area. |
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 |
000317538100022 |
Publication Date |
2013-02-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0048-9697 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.9 |
Times cited |
42 |
Open Access |
|
Notes |
; This research project was funded by the International Foundation for Science (IFS, Project Number W/4945-1). The authors wish to acknowledge the contribution of the Pangani Basin Water Office (PBWO) in Moshi, Tanzania; especially Ms. Arafa Maggidi in provision of valuable information and assistance with the sampling campaigns, and Salim Lyimo in mapping of the study area. The contributions of Mr. Peter Machibya of the Department of Geology, University of Dar es Salaam, Tanzania in sediment characterization; and Mr. Emmanuel Gwae, of the Government Chemists Laboratory Agency (GCLA) Dar es Salaam, Tanzania, for instrumental analysis of the water samples, are highly appreciated. Harieth Hellar-Kihampa acknowledges financial support from the Belgian Technical Agency (BTC). Govindan Malarvannan and Adrian Covaci acknowledge financial support from the University of Antwerp. ; |
Approved |
Most recent IF: 4.9; 2013 IF: 3.163 |
Call Number |
UA @ admin @ c:irua:105260 |
Serial |
5836 |
Permanent link to this record |
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Author |
Godoi, R.H.M.; Carneiro, B.H.B.; Paralovo, S.L.; Campos, V.P.; Tavares, T.M.; Evangelista, H.; Van Grieken, R.; Godoi, A.F.L. |
Title |
Indoor air quality of a museum in a subtropical climate : the Oscar Niemeyer museum in Curitiba, Brazil |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
The science of the total environment |
Abbreviated Journal |
|
Volume |
452 |
Issue |
|
Pages |
314-320 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The assessment of damage to indoor cultural heritage, in particular by pollutants, is nowadays a major and growing concern for curators and conservators. Nevertheless, although many museums have been widely investigated in Europe, the effects of particulate matter and gaseous pollutants in museums under tropical and subtropical climates and with different economic realities are still unclear. An important portion of the world's cultural heritage is currently in tropical countries where both human and financial resources for preserving museum collections are limited. Hence, our aim is to assess the damage that can be caused to the artwork by pollution in hot and humid environments, where air quality and microclimatic condition differences can cause deterioration. As a case study, particulate matter as well as gases were collected at the Oscar Niemeyer Museum (MON) in Curitiba, Brazil, where large modern and contemporary works of art are displayed. NO2, SO2, O3, Acetic Acid, Formic Acids and BTEX, in the ambient air, were sampled by means of passive diffusive sampling and their concentrations were determined by IC or GCMS. The particulate matter was collected in bulk form and analyzed with the use of energy dispersive X-ray fluorescence and aethalometer. The chemical compositions of individual particles were quantitatively elucidated, including low-Z components like C, N and O, as well as higher-Z elements, using automated electron probe microanalysis. The gaseous and particulate matter levels were then compared with the concentrations obtained for the same pollutants in other museums, located in places with different climates, and with some reference values provided by international cultural heritage conservation centers. Results are interpreted separately and as a whole with the specific aim of identifying compounds that could contribute to the chemical reactions taking place on the surfaces of artifacts and which could potentially cause irreversible damage to the artworks. |
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 |
000318530600034 |
Publication Date |
2013-03-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0048-9697; 1879-1026 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:106766 |
Serial |
8083 |
Permanent link to this record |
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|
Author |
Neyts, E.C.; Bogaerts, A. |
Title |
Combining molecular dynamics with Monte Carlo simulations : implementations and applications |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Theoretical chemistry accounts : theory, computation, and modeling |
Abbreviated Journal |
Theor Chem Acc |
Volume |
132 |
Issue |
2 |
Pages |
1320-12 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this contribution, we present an overview of the various techniques for combining atomistic molecular dynamics with Monte Carlo simulations, mainly in the context of condensed matter systems, as well as a brief summary of the main accelerated dynamics techniques. Special attention is given to the force bias Monte Carlo technique and its combination with molecular dynamics, in view of promising recent developments, including a definable timescale. Various examples of the application of combined molecular dynamics / Monte Carlo simulations are given, in order to demonstrate the enhanced simulation efficiency with respect to either pure molecular dynamics or Monte Carlo. |
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 |
000318294700010 |
Publication Date |
2012-12-19 |
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 |
1432-881X;1432-2234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.89 |
Times cited |
27 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.89; 2013 IF: 2.143 |
Call Number |
UA @ lucian @ c:irua:104725 |
Serial |
404 |
Permanent link to this record |
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Author |
Amin-Ahmadi, B.; Idrissi, H.; Galceran, M.; Colla, M.S.; Raskin, J.P.; Pardoen, T.; Godet, S.; Schryvers, D. |
Title |
Effect of deposition rate on the microstructure of electron beam evaporated nanocrystalline palladium thin films |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
539 |
Issue |
|
Pages |
145-150 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The influence of the deposition rate on the formation of growth twins in nanocrystalline Pd films deposited by electron beam evaporation is investigated using transmission electron microscopy. Statistical measurements prove that twin boundary (TB) density and volume fraction of grains containing twins increase with increasing deposition rate. A clear increase of the dislocation density was observed for the highest deposition rate of 5 Å/s, caused by the increase of the internal stress building up during deposition. Based on crystallographic orientation indexation using transmission electron microscopy, it can be concluded that a {111} crystallographic texture increases with increasing deposition rate even though the {101} crystallographic texture remains dominant. Most of the TBs are fully coherent without any residual dislocations. However, for the highest deposition rate (5 Å/s), the coherency of the TBs decreases significantly as a result of the interaction of lattice dislocations emitted during deposition with the growth TBs. The analysis of the grain boundary character of different Pd films shows that an increasing fraction of high angle grain boundaries with misorientation angles around 5565° leads to a higher potential for twin formation. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000321111100025 |
Publication Date |
2013-05-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0040-6090; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
13 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 1.879; 2013 IF: 1.867 |
Call Number |
UA @ lucian @ c:irua:109268 |
Serial |
807 |
Permanent link to this record |
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Author |
Hacimustafaoglu, M.; Celebi, S.; Bozdemir, S.E.; Ozgur, T.; Ozcan, I.; Guray, A.; Çakir, D. |
Title |
RSV frequency in children below 2 years hospitalized for lower respiratory tract infections |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Turkish Journal Of Pediatrics |
Abbreviated Journal |
Turkish J Pediatr |
Volume |
55 |
Issue |
2 |
Pages |
130-139 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Respiratory syncytial virus (RSV) is the most frequent agent of acute lower respiratory diseases and creates a significant burden of disease in children under 5 years all over the world. RSV causes severe lower respiratory tract infections (LRTI) that require hospitalization, especially in children <= 2 years. The aim of this study was to determine the incidence of RSV in children <= 2 years of age hospitalized for LRTI. Children <= 2 years of age hospitalized for one year for LRTI in the three largest hospitals of Bursa City Center, Turkey were evaluated. These three hospitals comprise 67.5% of all child beds in central Bursa, so this study allows us to evaluate the total disease burden and hospitalization incidence in central Bursa. Nasal swabs of the children were evaluated with RSV RespiStrip (Coris Bioconcept Organization). A total of 671 children were hospitalized for LRTI, and 254 (37.9%) had at least one hospitalization that was positive for RSV. Of all patients with LRTI, 54.8% (368/671) were hospitalized for acute bronchiolitis, while 45.2% (303/671) were hospitalized for pneumonia. Of patients with acute bronchiolitis or pneumonia, 41% (151/368) and 34% (103/303) were RSV+, respectively. Of RSV+ hospitalized children, 59.5% (151/254) were diagnosed as acute bronchiolitis and 40.5% (103/254) as pneumonia. The annual incidences of hospitalization due to LRTI, acute bronchiolitis and pneumonia were 20.5/1000, 11.2/1000 and 9.3/1000, respectively, in children <= 2 years of age. The annual incidences of hospitalization due to RSV+ LRTI, acute bronchiolitis and pneumonia were found as 7.8/1000, 4.6/1000 and 3.2/1000, respectively, in children <= 2 years of age. More than one-third of all children hospitalized with LRTI (38.3%, n=257) were in the 0-3 months age group. Compared to other age groups, RSV positivity was highest in that age group for acute bronchiolitis (57%), pneumonia (39.5%) and also total children with LRTI (47.9%). RSV is a very important cause of lower respiratory infections in children <= 2 years of age and occurred most frequently in those 0-3 months of age in our study. Since there is no other study assessing the annual hospitalization incidence of RSV+ LRTIs in one city in Turkey, our study has unique importance for providing valuable statistical data about RSV+ LRTIs. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Ankara |
Editor |
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Language |
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Wos |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0041-4301 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.32 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.32; 2013 IF: 0.339 |
Call Number |
UA @ lucian @ c:irua:128325 |
Serial |
4606 |
Permanent link to this record |
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Author |
Goris, B.; Roelandts, T.; Batenburg, K.J.; Heidari Mezerji, H.; Bals, S. |
Title |
Advanced reconstruction algorithms for electron tomography : from comparison to combination |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
127 |
Issue |
|
Pages |
40-47 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
In this work, the simultaneous iterative reconstruction technique (SIRT), the total variation minimization (TVM) reconstruction technique and the discrete algebraic reconstruction technique (DART) for electron tomography are compared and the advantages and disadvantages are discussed. Furthermore, we describe how the result of a three dimensional (3D) reconstruction based on TVM can provide objective information that is needed as the input for a DART reconstruction. This approach results in a tomographic reconstruction of which the segmentation is carried out in an objective manner. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000316659100007 |
Publication Date |
2012-08-02 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
63 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:101217 |
Serial |
72 |
Permanent link to this record |
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|
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Author |
Wang, A.; Turner, S.; Van Aert, S.; van Dyck, D. |
Title |
An alternative approach to determine attainable resolution directly from HREM images |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
133 |
Issue |
|
Pages |
50-61 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
The concept of resolution in high-resolution electron microscopy (HREM) is the power to resolve neighboring atoms. Since the resolution is related to the width of the point spread function of the microscope, it could in principle be determined from the image of a point object. However, in electron microscopy there are no ideal point objects. The smallest object is an individual atom. If the width of an atom is much smaller than the resolution of the microscope, this atom can still be considered as a point object. As the resolution of the microscope enters the sub-Å regime, information about the microscope is strongly entangled with the information about the atoms in HREM images. Therefore, we need to find an alternative method to determine the resolution in an object-independent way. In this work we propose to use the image wave of a crystalline object in zone axis orientation. Under this condition, the atoms of a column act as small lenses so that the electron beam channels through the atom column periodically. Because of this focusing, the image wave of the column can be much more peaked than the constituting atoms and can thus be a much more sensitive probe to measure the resolution. Our approach is to use the peakiness of the image wave of the atom column to determine the resolution. We will show that the resolution can be directly linked to the total curvature of the atom column wave. Moreover, we can then directly obtain the resolution of the microscope given that the contribution from the object is known, which is related to the bounding energy of the atom. The method is applied on an experimental CaTiO3 image wave. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000324471800007 |
Publication Date |
2013-05-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
2.843 |
Times cited |
|
Open Access |
|
Notes |
FWO; Hercules; Esteem2; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:109919 |
Serial |
90 |
Permanent link to this record |
|
|
|
Author |
de Backer, A.; Martinez, G.T.; Rosenauer, A.; Van Aert, S. |
Title |
Atom counting in HAADF STEM using a statistical model-based approach : methodology, possibilities, and inherent limitations |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
134 |
Issue |
|
Pages |
23-33 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In the present paper, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. In order to count the number of atoms, it is assumed that the total scattered intensity scales with the number of atoms per atom column. These intensities are quantitatively determined using model-based statistical parameter estimation theory. The distribution describing the probability that intensity values are generated by atomic columns containing a specific number of atoms is inferred on the basis of the experimental scattered intensities. Finally, the number of atoms per atom column is quantified using this estimated probability distribution. The number of atom columns available in the observed STEM image, the number of components in the estimated probability distribution, the width of the components of the probability distribution, and the typical shape of a criterion to assess the number of components in the probability distribution directly affect the accuracy and precision with which the number of atoms in a particular atom column can be estimated. It is shown that single atom sensitivity is feasible taking the latter aspects into consideration. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000324474900005 |
Publication Date |
2013-05-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
48 |
Open Access |
|
Notes |
FWO; Esteem2; FP 2007-2013; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:109916 |
Serial |
162 |
Permanent link to this record |
|
|
|
Author |
den Dekker, A.J.; Gonnissen, J.; de Backer, A.; Sijbers, J.; Van Aert, S. |
Title |
Estimation of unknown structure parameters from high-resolution (S)TEM images : what are the limits? |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
134 |
Issue |
|
Pages |
34-43 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Statistical parameter estimation theory is proposed as a quantitative method to measure unknown structure parameters from electron microscopy images. Images are then purely considered as data planes from which structure parameters have to be determined as accurately and precisely as possible using a parametric statistical model of the observations. For this purpose, an efficient algorithm is proposed for the estimation of atomic column positions and intensities from high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. Furthermore, the so-called CramérRao lower bound (CRLB) is reviewed to determine the limits to the precision with which continuous parameters such as atomic column positions and intensities can be estimated. Since this lower bound can only be derived for continuous parameters, alternative measures using the principles of detection theory are introduced for problems concerning the estimation of discrete parameters such as atomic numbers. An experimental case study is presented to show the practical use of these measures for the optimization of the experiment design if the purpose is to decide between the presence of specific atom types using STEM images. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000324474900006 |
Publication Date |
2013-06-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
31 |
Open Access |
|
Notes |
FWO; FP 2007-2013; Esteem2; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:109240 |
Serial |
1083 |
Permanent link to this record |
|
|
|
Author |
Heidari, H.; van den Broek, W.; Bals, S. |
Title |
Quantitative electron tomography : the effect of the three-dimensional point spread function |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
135 |
Issue |
|
Pages |
1-5 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The intensity levels in a three-dimensional (3D) reconstruction, obtained by electron tomography, can be influenced by several experimental imperfections. Such artifacts will hamper a quantitative interpretation of the results. In this paper, we will correct for artificial intensity variations by determining the 3D point spread function (PSF) of a tomographic reconstruction based on high angle annular dark field scanning transmission electron microscopy. The large tails of the PSF cause an underestimation of the intensity of smaller particles, which in turn hampers an accurate radius estimate. Here, the error introduced by the PSF is quantified and corrected a posteriori. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000326941500001 |
Publication Date |
2013-06-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
6 |
Open Access |
|
Notes |
Esteem2; Sunflower; esteem2_jra4 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:111397 |
Serial |
2756 |
Permanent link to this record |
|
|
|
Author |
Lichtert, S.; Verbeeck, J. |
Title |
Statistical consequences of applying a PCA noise filter on EELS spectrum images |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
125 |
Issue |
|
Pages |
35-42 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Principal component analysis (PCA) noise filtering is a popular method to remove noise from experimental electron energy loss (EELS) spectrum images. Here, we investigate the statistical behaviour of this method by applying it on a simulated data set with realistic noise levels. This phantom data set provides access to the true values contained in the data set as well as to many different realizations of the noise. Using least squares fitting and parameter estimation theory, we demonstrate that even though the precision on the estimated parameters can be better as the CramérRao lower bound, a significant bias is introduced which can alter the conclusions drawn from experimental data sets. The origin of this bias is in the incorrect retrieval of the principal loadings for noisy data. Using an expression for the bias and precision of the singular values from literature, we present an evaluation criterion for these singular values based on the noise level and the amount of information present in the data set. This criterion can help to judge when to avoid PCA noise filtering in practical situations. Further we show that constructing elemental maps of PCA noise filtered data using the background subtraction method, does not guarantee an increase in the signal to noise ratio due to correlation of the spectral data as a result of the filtering process. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000314679700006 |
Publication Date |
2012-10-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
54 |
Open Access |
|
Notes |
Fwo; Countatoms; Vortex; Esteem 312483; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:105293 |
Serial |
3153 |
Permanent link to this record |
|
|
|
Author |
Béché, A.; Rouviere, J.L.; Barnes, J.P.; Cooper, D. |
Title |
Strain measurement at the nanoscale : comparison between convergent beam electron diffraction, nano-beam electron diffraction, high resolution imaging and dark field electron holography |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
131 |
Issue |
|
Pages |
10-23 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Convergent beam electron diffraction (CBED), nano-beam electron diffraction (NBED or NBD), high resolution imaging (HRTEM and HRSTEM) and dark field electron holography (DFEH or HoloDark) are five TEM based techniques able to quantitatively measure strain at the nanometer scale. In order to demonstrate the advantages and disadvantages of each technique, two samples composed of epitaxial silicon-germanium layers embedded in a silicon matrix have been investigated. The five techniques are then compared in terms of strain precision and accuracy, spatial resolution, field of view, mapping abilities and ease of performance and analysis. (C) 2013 Elsevier By. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000322631200002 |
Publication Date |
2013-04-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
73 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
Call Number |
UA @ lucian @ c:irua:109774 |
Serial |
3171 |
Permanent link to this record |
|
|
|
Author |
Vanmeert, F.; Mudronja, D.; Fazinic, S.; Janssens, K.; Tibljas, D. |
Title |
Semi-quantitative analysis of the formation of a calcium oxalate protective layer for monumental limestone using combined micro-XRF and micro-XRPD |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
X-Ray Spectrom |
Volume |
42 |
Issue |
4 |
Pages |
256-261 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A current method for the protection of cretaceous limestone present in various monuments consists of performing a passivating treatment with ammonium oxalate (AmOx). A calcium oxalate protective layer is formed on the surface and enhances the acid resistance of the stone. The in-depth formation of the calcium oxalate layer was investigated on cross sections by using combined micro X-ray fluorescence and micro X-ray powder diffraction (mu XRF/mu XRPD). XRPD showed the presence of both whewellite and weddellite in the calcite stone matrix. A correction was made for sample misalignment, which was visible in both the fluorescence and the diffraction line measurements. A semi-quantitative analysis was performed on the basis of Klug's equation for a two-phase mixture (the presence of weddellite was neglected) without the need for a known reference sample. By assuming two extreme compositions for a reference weight fraction (1 and 99wt%), it was possible to obtain whewellite concentration profiles, which can be used for comparing the effectiveness of different methods for the application of AmOx to the stone surface and the effect of treatment time and AmOx concentration used. It is shown that for the relative amounts of whewellite formed, the differences due to the assumed weight fractions are smaller than the errors due to sample heterogeneity and preferred orientation. Copyright (c) 2013 John Wiley & Sons, Ltd. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000320727900015 |
Publication Date |
2013-05-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.298 |
Times cited |
5 |
Open Access |
|
Notes |
; The authors would like to thank De Nolf W. for his valuable feedback on the analysis of the X-ray diffraction data. We acknowledge SOLEIL for provision of SR facilities (proposal ID 20100979), and we would like to thank Dr. C. Mocuta for his assistance at the DIFFABS beamline. This research was supported by the Interuniversity Attraction Poles Program – 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) projects no. G.0704.08 and G.01769.09. The EU Community's FP7 Research Infrastructures program for the CHARISMA Project (grant agreement 228330) and, within framework in particular, the access possibilities to the SOLEIL and IPANEMA facilities are also acknowledged. ; |
Approved |
Most recent IF: 1.298; 2013 IF: 1.187 |
Call Number |
UA @ admin @ c:irua:109579 |
Serial |
5827 |
Permanent link to this record |
|
|
|
Author |
Van Grieken, R. |
Title |
Editorial : award for best X-Ray Spectrometry referee during 2011-2012 |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
|
Volume |
42 |
Issue |
1 |
Pages |
3 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000314971600002 |
Publication Date |
2012-12-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:104628 |
Serial |
7830 |
Permanent link to this record |
|
|
|
Author |
Van Grieken, R. |
Title |
Editorial : introducing Dr Markowicz as X-Ray Spectrometry's new associate editor for Europe |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
|
Volume |
42 |
Issue |
4 |
Pages |
175 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
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Language |
|
Wos |
000320727900001 |
Publication Date |
2013-06-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:108738 |
Serial |
7832 |
Permanent link to this record |
|
|
|
Author |
Van Grieken, R. |
Title |
New members of the editorial board of X-ray Spectrometry |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
|
Volume |
42 |
Issue |
1 |
Pages |
1-2 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
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Language |
|
Wos |
000314971600001 |
Publication Date |
2012-12-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:104627 |
Serial |
8301 |
Permanent link to this record |
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|
|
Author |
Van Rompaey, S.; Dachraoui, W.; Turner, S.; Podyacheva, O.Y.; Tan, H.; Verbeeck, J.; Abakumov, A.; Hadermann, J. |
Title |
Layered oxygen vacancy ordering in Nb-doped SrCo1-xFexO3-\delta perovskite |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2013 |
Publication |
Zeitschrift für Kristallographie |
Abbreviated Journal |
Z Krist-Cryst Mater |
Volume |
228 |
Issue |
1 |
Pages |
28-34 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structure of SrCo0.7Fe0.2Nb0.1O2.72 was determined using a combination of precession electron diffraction (PED), high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and spatially resolved electron energy loss spectroscopy (STEM-EELS). The structure has a tetragonal P4/mmm symmetry with cell parameters a = b = a(p), c = 2a(p) (a(p) being the cell parameter of the perovskite parent structure). Octahedral BO2 layers alternate with the anion-deficient BO1.4 layers, the different B cations are randomly distributed over both layers. The specific feature of the SrCo0.7Fe0.2NB0.1O2.72 microstructure is a presence of extensive nanoscale twinning resulting in domains with alignment of the tetragonal c-axis along all three cubic direction of the perovskite subcell. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
München |
Editor |
|
Language |
|
Wos |
000315475900004 |
Publication Date |
2013-01-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2194-4946; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.179 |
Times cited |
9 |
Open Access |
|
Notes |
Fwo; Countatoms |
Approved |
Most recent IF: 3.179; 2013 IF: NA |
Call Number |
UA @ lucian @ c:irua:107698UA @ admin @ c:irua:107698 |
Serial |
1808 |
Permanent link to this record |
|
|
|
Author |
Bertoni, G.; Grillo, V.; Brescia, R.; Ke, X.; Bals, S.; Catellani, A.; Li, H.; Manna, L. |
Title |
Direct determination of polarity, faceting, and core location in colloidal core/shell wurtzite semiconductor nanocrystals |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
6 |
Issue |
7 |
Pages |
6453-6461 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The ability to determine the atomic arrangement and termination of various facets of surfactant-coated nanocrystals is of great importance for understanding their growth mechanism and their surface properties and represents a critical piece of information that can be coupled to other experimental techniques and to calculations. This is especially appealing in the study of nanocrystals that can be grown in strongly anisotropic shapes, for which the relative growth rates of various facets can be influenced under varying reaction conditions. Here we show that in two representative cases of rod-shaped nanocrystals in the wurtzite phase (CdSe(core)/CdS(shell) and ZnSe(core)/ZnS(shell) nanorods) the terminations of the polar facets can be resolved unambiguously by combining advanced electron microscopy techniques, such as aberration-corrected HRTEM with exit wave reconstruction or aberration-corrected HAADF-STEM. The [0001] and [000-1] polar directions of these rods, which grow preferentially along their c-axis, are revealed clearly, with one side consisting of the Cd (or Zn)-terminated (0001) facet and the other side with a pronounced faceting due to Cd (or Zn)-terminated {10-1-1} facets. The lateral faceting of the rods is instead dominated by three nonpolar {10-10} facets. The core buried in the nanostructure can be localized in both the exit wave phase and HAADF-STEM images. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000306673800079 |
Publication Date |
2012-06-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
63 |
Open Access |
|
Notes |
The authors gratefully acknowledge funding from the European Research Council under grant number 240111 (NANO-ARCH) and the financial support from the Flemish Hercules 3 Programme for large infrastructures. G.B. and V.G. thank E. Rotunno for his help with STEM_CELL and IWFR. |
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
Call Number |
UA @ lucian @ c:irua:101138 |
Serial |
710 |
Permanent link to this record |
|
|
|
Author |
Sánchez-Iglesias, A.; Grzelczak, M.; Altantzis, T.; Goris, B.; Pérez-Juste, J.; Bals, S.; Van Tendeloo, G.; Donaldson, S.H.; Chmelka, B.F.; Israelachvili, J.N.; Liz-Marzán, L.M.; |
Title |
Hydrophobic interactions modulate self-assembly of nanoparticles |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
6 |
Issue |
12 |
Pages |
11059-11065 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Hydrophobic interactions constitute one of the most important types of nonspecific interactions in biological systems, which emerge when water molecules rearrange as two hydrophobic species come close to each other. The prediction of hydrophobic interactions at the level of nanoparticles (Brownian objects) remains challenging because of uncontrolled diffusive motion of the particles. We describe here a general methodology for solvent-induced, reversible self-assembly of gold nanoparticles into 3D clusters with well-controlled sizes. A theoretical description of the process confirmed that hydrophobic interactions are the main driving force behind nanoparticle aggregation. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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Language |
|
Wos |
000312563600070 |
Publication Date |
2012-11-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
311 |
Open Access |
|
Notes |
267867 Plasma Quo; 246791 Countatoms; 262348 Esmi |
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
Call Number |
UA @ lucian @ c:irua:105292 |
Serial |
1538 |
Permanent link to this record |
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Author |
De Trizio, L.; Figuerola, A.; Manna, L.; Genovese, A.; George, C.; Brescia, R.; Saghi, Z.; Simonutti, R.; van Huis, M.; Falqui, A. |
Title |
Size-tunable, hexagonal plate-like Cu3P and Janus-like Cu-Cu3P nanocrystals |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
6 |
Issue |
1 |
Pages |
32-41 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
We describe two synthesis approaches to colloidal Cu3P nanocrystals using trioctylphosphine (TOP) as phosphorus precursor. One approach is based on the homogeneous nucleation of small Cu3P nanocrystals with hexagonal plate-like morphology and with sizes that can be tuned from 5 to 50 nm depending on the reaction time. In the other approach, metallic Cu nanocrystals are nucleated first and then they are progressively phosphorized to Cu3P. In this case, intermediate Janus-like dimeric nanoparticles can be isolated, which are made of two domains of different materials, Cu and Cu3P, sharing a flat epitaxial interface. The Janus-like nanoparticles can be transformed back to single-crystalline copper particles if they are annealed at high temperature under high vacuum conditions, which makes them an interesting source of phosphorus. The features of the Cu Cu3P Janus-like nanoparticles are compared with those of the Wiped microstructure discovered more than two decades ago in the rapidly quenched Cu Cu3P eutectic of the Cu P alloy, suggesting that other alloy/eutectic systems that display similar behavior might give origin to nanostructures with flat, epitaxial Interface between domains of two diverse materials. Finally, the electrochemical properties of the copper phosphide plates are studied, and they are found to be capable of undergoing lithiation/delithiation through a displacement reaction, while the Janus-like Cu Cu3P particles do not display an electrochemical behavior that would make them suitable for applications in batteries. |
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 |
000299368300006 |
Publication Date |
2011-12-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
60 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
Call Number |
UA @ lucian @ c:irua:99172 |
Serial |
3039 |
Permanent link to this record |
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Author |
Tirumalasetty, G.K.; van Huis, M.A.; Kwakernaak, C.; Sietsma, J.; Sloof, W.G.; Zandbergen, H.W. |
Title |
Deformation-induced austenite grain rotation and transformation in TRIP-assisted steel |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
Volume |
60 |
Issue |
3 |
Pages |
1311-1321 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Uniaxial straining experiments were performed on a rolled and annealed Si-alloyed TRIP (transformation-induced plasticity) steel sheet in order to assess the role of its microstructure on the mechanical stability of austenite grains with respect to martensitic transformation. The transformation behavior of individual metastable austenite grains was studied both at the surface and inside the bulk of the material using electron back-scattered diffraction (EBSD) and X-ray diffraction (XRD) by deforming the samples to different strain levels up to about 20%. A comparison of the XRD and EBSD results revealed that the retained austenite grains at the surface have a stronger tendency to transform than the austenite grains in the bulk of the material. The deformation-induced changes of individual austenite grains before and after straining were monitored with EBSD. Three different types of austenite grains can be distinguished that have different transformation behaviors: austenite grains at the grain boundaries between ferrite grains, twinned austenite grains, and embedded austenite grains that are completely surrounded by a single ferrite grain. It was found that twinned austenite grains and the austenite grains present at the grain boundaries between larger ferrite grains typically transform first, i.e. are less stable, in contrast to austenite grains that are completely embedded in a larger ferrite grain. In the latter case, straining leads to rotations of the harder austenite grain within the softer ferrite matrix before the austenite transforms into martensite. The analysis suggests that austenite grain rotation behavior is also a significant factor contributing to enhancement of the ductility. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000301157900054 |
Publication Date |
2011-12-19 |
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 |
1359-6454; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.301 |
Times cited |
80 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 5.301; 2012 IF: 3.941 |
Call Number |
UA @ lucian @ c:irua:97210 |
Serial |
630 |
Permanent link to this record |
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Author |
Colla, M.-S.; Wang, B.; Idrissi, H.; Schryvers, D.; Raskin, J.-P.; Pardoen, T. |
Title |
High strength-ductility of thin nanocrystalline palladium films with nanoscale twins : on-chip testing and grain aggregate model |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
Volume |
60 |
Issue |
4 |
Pages |
1795-1806 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The mechanical behaviour of thin nanocrystalline palladium films with an ∼30 nm in plane grain size has been characterized on chip under uniaxial tension. The films exhibit a large strain hardening capacity and a significant increase in the strength with decreasing thickness. Transmission electron microscopy has revealed the presence of a moderate density of growth nanotwins interacting with dislocations. A semi-analytical grain aggregate model is proposed to investigate the impact of different contributions to the flow behaviour, involving the effect of twins, of grain size and of the presence of a thin surface layer. This model provides guidelines to optimizing the strength/ductility ratio of the films. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000301989500035 |
Publication Date |
2012-02-02 |
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 |
1359-6454; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.301 |
Times cited |
38 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: 5.301; 2012 IF: 3.941 |
Call Number |
UA @ lucian @ c:irua:94213 |
Serial |
1465 |
Permanent link to this record |
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Author |
Peelaers, H.; Partoens, B.; Peeters, F.M. |
Title |
Free-standing Si and Ge, and Ge/Si core-shell semiconductor nanowires |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
Acta physica Polonica: A: general physics, solid state physics, applied physics
T2 – WELCOME Scientific Meeting on Hybrid Nanostructures, AUG 28-31, 2011, Torun, POLAND |
Abbreviated Journal |
Acta Phys Pol A |
Volume |
122 |
Issue |
2 |
Pages |
294-298 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The properties of free-standing silicon and germanium nanowires oriented along the [110] direction are studied using different first principles methods. We show the corrections due to quasi-particles to the band structures obtained using the local-density approximation. The formation energies of B and P doped nanowires are calculated, both in the absence and presence of dangling bond defects and we link these to experimental results. Furthermore, we report on the phonon properties of pure Si and Ge nanowires, as well as Ge/Si core-shell nanowires, and discuss the differences between them. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Warszawa |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0587-4246 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
0.469 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.469; 2012 IF: 0.531 |
Call Number |
UA @ lucian @ c:irua:101896 |
Serial |
1277 |
Permanent link to this record |
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Author |
Boschker, H.; Verbeeck, J.; Egoavil, R.; Bals, S.; Van Tendeloo, G.; Huijben, M.; Houwman, E.P.; Koster, G.; Blank, D.H.A.; Rijnders, G. |
Title |
Preventing the reconstruction of the polar discontinuity at oxide heterointerfaces |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
22 |
Issue |
11 |
Pages |
2235-2240 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Perovskite oxide heteroepitaxy receives much attention because of the possibility to combine the diverse functionalities of perovskite oxide building blocks. A general boundary condition for the epitaxy is the presence of polar discontinuities at heterointerfaces. These polar discontinuities result in reconstructions, often creating new functionalities at the interface. However, for a significant number of materials these reconstructions are unwanted as they alter the intrinsic materials properties at the interface. Therefore, a strategy to eliminate this reconstruction of the polar discontinuity at the interfaces is required. We show that the use of compositional interface engineering can prevent the reconstruction at the La0.67Sr0.33MnO3/SrTiO3 (LSMO/STO) interface. The polar discontinuity at this interface can be removed by the insertion of a single La0.33Sr0.67O layer, resulting in improved interface magnetization and electrical conductivity. |
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 |
000304749600002 |
Publication Date |
2012-03-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1616-301X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
72 |
Open Access |
|
Notes |
We wish to acknowledge the financial support of the Dutch Science Foundation (NWO) and the Dutch Nanotechnology program NanoNed. S. B. acknowledges the financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. J. V. and G. V. T. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC grant N246791 – COUNTATOMS. R. E. acknowledges funding by the European Union Council under the 7th Framework Program (FP7) grant NNMP3-LA-2010-246102 IFOX. We thank Sandra Van Aert for stimulating discussions. |
Approved |
Most recent IF: 12.124; 2012 IF: 9.765 |
Call Number |
UA @ lucian @ c:irua:98907UA @ admin @ c:irua:98907 |
Serial |
2712 |
Permanent link to this record |
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Author |
Van Tendeloo, G.; Bals, S.; Van Aert, S.; Verbeeck, J.; van Dyck, D. |
Title |
Advanced electron microscopy for advanced materials |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
24 |
Issue |
42 |
Pages |
5655-5675 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
The idea of this Review is to introduce newly developed possibilities of advanced electron microscopy to the materials science community. Over the last decade, electron microscopy has evolved into a full analytical tool, able to provide atomic scale information on the position, nature, and even the valency atoms. This information is classically obtained in two dimensions (2D), but can now also be obtained in 3D. We show examples of applications in the field of nanoparticles and interfaces. |
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 |
000310602200001 |
Publication Date |
2012-08-21 |
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 |
0935-9648; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
107 |
Open Access |
|
Notes |
This work was supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No 246791 – COUNTATOMS. J.V. Acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium). The Qu-Ant-EM microscope was partly funded by the Hercules Fund from the Flemish Government. We thank Rafal Dunin-Borkowski for providing Figure 5d. The authors would like to thank the colleagues who have contributed to this work over the years, including K.J. Batenburg, R. Erni, B. Goris, F. Leroux, H. Lichte, A. Lubk, B. Partoens, M. D. Rossell, P. Schattschneider, B. Schoeters, D. Schryvers, H. Tan, H. Tian, S. Turner, M. van Huis. ECASJO_; |
Approved |
Most recent IF: 19.791; 2012 IF: 14.829 |
Call Number |
UA @ lucian @ c:irua:100470UA @ admin @ c:irua:100470 |
Serial |
70 |
Permanent link to this record |
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Author |
Van Aert, S.; Turner, S.; Delville, R.; Schryvers, D.; Van Tendeloo, G.; Salje, E.K.H. |
Title |
Direct observation of ferrielectricity at ferroelastic domain boundaries in CaTiO3 by electron microscopy |
Type |
A1 Journal article |
Year ![sorted by Year field, descending order (down)](img/sort_desc.gif) |
2012 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
24 |
Issue |
4 |
Pages |
523-527 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
High-resolution aberration-corrected transmission electron microscopy aided by statistical parameter estimation theory is used to quantify localized displacements at a (110) twin boundary in orthorhombic CaTiO3. The displacements are 36 pm for the Ti atoms and confined to a thin layer. This is the first direct observation of the generation of ferroelectricity by interfaces inside this material which opens the door for domain boundary engineering. |
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 |
|
Wos |
000299156400011 |
Publication Date |
2011-12-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
0935-9648; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
150 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 19.791; 2012 IF: 14.829 |
Call Number |
UA @ lucian @ c:irua:94110 |
Serial |
717 |
Permanent link to this record |