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Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
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Title |
Statistical parameter estimation theory : principles and simulation studies |
Type |
H2 Book chapter |
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Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
29-72 |
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Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
In this chapter, the principles of statistical parameter estimation theory for a quantitative analysis of atomic-resolution electron microscopy images are introduced. Within this framework, electron microscopy images are described by a parametric statistical model. Here, parametric models are introduced for different types of electron microscopy images: reconstructed exit waves, annular dark-field (ADF) scanning transmission electron microscopy (STEM) images, and simultaneously acquired ADF and annular bright-field (ABF) STEM images. Furthermore, the Cramér-Rao lower bound (CRLB) is introduced, i.e. a theoretical lower bound on the variance of any unbiased estimator. This CRLB is used to quantify the precision of the structure parameters of interest, such as the atomic column positions and the integrated atomic column intensities. |
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Publication Date |
2021-03-06 |
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Abbreviated Series Title |
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Series Volume |
217 |
Series Issue |
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Edition |
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ISSN |
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ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
Not_Open_Access |
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Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:177527 |
Serial |
6788 |
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Permanent link to this record |
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Author |
Yan, Y.; Wang, L.-X.; Ke, X.; Van Tendeloo, G.; Wu, X.-S.; Yu, D.-P.; Liao, Z.-M. |
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Title |
High-mobility Bi2Se3 nanoplates manifesting quantum oscillations of surface states in the sidewalls |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
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Volume |
4 |
Issue |
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Pages |
3817-7 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Magnetotransport measurements of topological insulators are very important to reveal the exotic topological surface states for spintronic applications. However, the novel properties related to the surface Dirac fermions are usually accompanied by a large linear magnetoresistance under perpendicular magnetic field, which makes the identification of the surface states obscure. Here, we report prominent Shubnikov-de Haas (SdH) oscillations under an in-plane magnetic field, which are identified to originate from the surface states in the sidewalls of topological insulator Bi2Se3 nanoplates. Importantly, the SdH oscillations appear with a dramatically weakened magnetoresistance background, offering an easy path to probe the surface states directly when the coexistence of surface states and bulk conduction is inevitable. Moreover, under a perpendicular magnetic field, the oscillations in Hall conductivity have peak-to-valley amplitudes of 2 e(2)/h, giving confidence to achieve a quantum Hall effect in this system. A cross-section view of the nanoplate shows that the sidewall is (015) facet dominant and therefore forms a 586 angle with regard to the top/ bottom surface instead of being perpendicular; this gives credit to the surface states' behavior as two-dimensional transport. |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
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Wos |
000330044700008 |
Publication Date |
2014-01-22 |
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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 |
2045-2322; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.259 |
Times cited |
31 |
Open Access |
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Notes |
ERC grant Nu246791 – COUNTATOMS |
Approved |
Most recent IF: 4.259; 2014 IF: 5.578 |
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Call Number |
UA @ lucian @ c:irua:114815 |
Serial |
1436 |
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Permanent link to this record |
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Author |
Liang, D.; Follens, L.R.A.; Aerts, A.; Martens, J.A.; Van Tendeloo, G.; Kirschhock, C.E.A. |
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Title |
TEM observation of aggregation steps in room-temperature silicalite-1 zeolite formation |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
Journal of physical chemistry C |
Abbreviated Journal |
J Phys Chem C |
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Volume |
111 |
Issue |
39 |
Pages |
14283-14285 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Wos |
000249838300002 |
Publication Date |
2007-09-11 |
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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; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
41 |
Open Access |
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Notes |
ESA; IWT – Flanders; FWO |
Approved |
Most recent IF: 4.536; 2007 IF: NA |
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Call Number |
UA @ lucian @ c:irua:66617 |
Serial |
3481 |
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Permanent link to this record |
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Author |
Mourdikoudis, S.; Chirea, M.; Altantzis, T.; Pastoriza-Santos, I.; Perez-Juste, J.; Silva, F.; Bals, S.; Liz-Marzan, L.M. |
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Title |
Dimethylformamide-mediated synthesis of water-soluble platinum nanodendrites for ethanol oxidation electrocatalysis |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
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Volume |
5 |
Issue |
11 |
Pages |
4776-4784 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Herein we describe the synthesis of water-soluble platinum nanodendrites in dimethylformamide (DMF), in the presence of polyethyleneimine (PEI) as a stabilizing agent. The average size of the dendrites is in the range of 20-25 nm while their porosity can be tuned by modifying the concentration of the metal precursor. Electron tomography revealed different crystalline orientations of nanocrystallites in the nanodendrites and allowed a better understanding of their peculiar branching and porosity. The high surface area of the dendrites (up to 22 m(2) g(-1)) was confirmed by BET measurements, while X-ray diffraction confirmed the abundance of high-index facets in the face-centered-cubic crystal structure of Pt. The prepared nanodendrites exhibit excellent performance in the electrocatalytic oxidation of ethanol in alkaline solution. Sensing, selectivity, cycleability and great tolerance toward poisoning were demonstrated by cyclic voltammetry measurements. |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Wos |
000319008700028 |
Publication Date |
2013-04-03 |
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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 |
2040-3364;2040-3372; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7.367 |
Times cited |
50 |
Open Access |
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Notes |
Esf; 262348 Esmi |
Approved |
Most recent IF: 7.367; 2013 IF: 6.739 |
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Call Number |
UA @ lucian @ c:irua:109060 |
Serial |
705 |
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Permanent link to this record |
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Author |
Javon, E.; Gaceur, M.; Dachraoui, W.; Margeat, O.; Ackermann, J.; Ilenia Saba, M.; Delugas, P.; Mattoni, A.; Bals, S.; Van Tendeloo, G. |
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Title |
Competing forces in the self-assembly of coupled ZnO nanopyramids |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume |
9 |
Issue |
9 |
Pages |
3685-3694 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Self-assembly (SA) of nanostructures has recently gained increasing interest. A clear understanding of the process is not straightforward since SA of nanoparticles is a complex multiscale phenomenon including different driving forces. Here, we study the SA between aluminum doped ZnO nanopyramids into couples by combining inorganic chemistry and advanced electron microscopy techniques with atomistic simulations. Our results show that the SA of the coupled nanopyramids is controlled first by morphology, as coupling only occurs in the case of pyramids with well-developed facets of the basal planes. The combination of electron microscopy and atomistic modeling reveals that the coupling is further driven by strong ligandligand interaction between the bases of the pyramids as dominant force, while screening effects due to Al doping or solvent as well as corecore interaction are only minor contributions. Our combined approach provides a deeper understanding of the complex interplay between the interactions at work in the coupled SA of ZnO nanopyramids. |
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Wos |
000353867000030 |
Publication Date |
2015-03-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
21 |
Open Access |
OpenAccess |
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Notes |
Esmi; 335078 Colouratom; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:125978 |
Serial |
434 |
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Permanent link to this record |
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Author |
Schattschneider, P.; Ennen, I.; Stoger-Pollach, M.; Verbeeck, J. |
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Title |
Circular dichroism in the electron microscope: progress and applications (invited) |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
107 |
Issue |
9 |
Pages |
09d311,1-09d311,6 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
According to theory, x-ray magnetic circular dichroism in a synchrotron is equivalent to energy loss magnetic chiral dichroism (EMCD) in a transmission electron microscope (TEM). After a synopsis of the development of EMCD, the theoretical background is reviewed and recent results are presented, focusing on the study of magnetic nanoparticles for ferrofluids and Heusler alloys for spintronic devices. Simulated maps of the dichroic strength as a function of atom position in the crystal allow evaluating the influence of specimen thickness and sample tilt on the experimental EMCD signal. Finally, the possibility of direct observation of chiral electronic transitions with atomic resolution in a TEM is discussed. |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
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Language |
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Wos |
000277834300276 |
Publication Date |
2010-05-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
28 |
Open Access |
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Notes |
Esteem |
Approved |
Most recent IF: 2.068; 2010 IF: 2.079 |
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Call Number |
UA @ lucian @ c:irua:83653UA @ admin @ c:irua:83653 |
Serial |
361 |
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Permanent link to this record |
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Author |
Maccato, C.; Simon, Q.; Carraro, G.; Barreca, D.; Gasparotto, A.; Lebedev, O.I.; Turner, S.; Van Tendeloo, G. |
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Title |
Zinc and copper oxides functionalized with metal nanoparticles : an insight into their nano-organization |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of advanced microscopy research |
Abbreviated Journal |
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Volume |
7 |
Issue |
2 |
Pages |
84-90 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Ag/ZnO and Au/CuxO (x = 1, 2) nanocomposites supported on Si(100) and polycrystalline Al2O3 were synthesised by hybrid approaches, combining chemical vapor deposition (either thermal or plasma-assisted) of host oxide matrices and subsequent radio frequency-sputtering of guest metal particles. The influence of the adopted synthetic parameters on the nanocomposite morphological and compositional features was investigated by field emission-scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Results confirm the synthesis of ZnO and CuxO nanoarchitectures, characterized by a tailored morphology and an intimate metal/oxide contact. A careful control of the processing conditions enabled a fine tuning of the mutual constituent distribution, opening thus attractive perspectives for the engineering of advanced nanomaterials. |
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Wos |
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Publication Date |
2012-12-04 |
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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 |
2156-7573;2156-7581; |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
Esteem |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:105298 |
Serial |
3932 |
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Permanent link to this record |
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Author |
Zhang, L.; Turner, S.; Brosens, F.; Verbeeck, J. |
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Title |
Model-based determination of dielectric function by STEM low-loss EELS |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
81 |
Issue |
3 |
Pages |
035102 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Theory of quantum systems and complex systems |
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Abstract |
Dielectric properties of materials are crucial in describing the electromagnetic response of materials. As devices are becoming considerably smaller than the optical wavelength, the conventional measuring methods based on optical response are limited by their spatial resolution. Electron energy loss spectroscopy performed in a scanning transmission electron microscope is a good alternative to obtain the dielectric properties with excellent spatial resolution. Due to the overlap of diffraction discs in scanning transmission electron microscopy, it is difficult to apply conventional experimental settings to suppress retardation losses. In this contribution, a relativistic dielectric model for the loss function is presented which is used in a model based optimization scheme to estimate the complex dielectric function of a material. The method is applied to experiments on bulk diamond and SrTiO3 and shows a good agreement with optical reference data when retardation effects are included. Application of this technique to nanoparticles is possible but several theoretical assumptions made in the model of the loss function are violated and interpretation becomes problematic. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000274002300027 |
Publication Date |
2010-01-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
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Notes |
Esteem – 026019; Fwo |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:81258UA @ admin @ c:irua:81258 |
Serial |
2098 |
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Permanent link to this record |
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Author |
Djoković, V.; Krsmanović, R.; Božanić, D.K.; McPherson, M.; Van Tendeloo, G.; Nair, P.S.; Georges, M.K.; Radhakrishnan, T. |
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Title |
Adsorption of sulfur onto a surface of silver nanoparticles stabilized with sago starch biopolymer |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Colloids and surfaces: B : biointerfaces |
Abbreviated Journal |
Colloid Surface B |
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Volume |
73 |
Issue |
1 |
Pages |
30-35 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Adsorption of sulfide ions onto a surface of starch capped silver nanoparticles upon addition of thioacetamide was investigated. UVvis absorption spectroscopy revealed that the adsorption of the sulfide ion on the surface of the silver nanoparticles induced damping as well as blue shift of the silver surface plasmon resonance band. Further increase in thioacetamide concentration led to shift of the resonance band toward higher wavelengths indicating the formation of the continuous Ag2S layer on the silver surface. Thus fabricated nanoparticles were investigated using electron microscopy techniques (TEM, HRTEM, and HAADF-STEM) and X-ray photoelectron spectroscopy (XPS), which confirmed their coreshell structure. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000268657500005 |
Publication Date |
2009-05-05 |
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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 |
0927-7765; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.887 |
Times cited |
41 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.887; 2009 IF: 2.600 |
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Call Number |
UA @ lucian @ c:irua:77972 |
Serial |
66 |
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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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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 |
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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 |
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Permanent link to this record |
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Author |
Turner, S.; Tavernier, S.M.F.; Huyberechts, G.; Bals, S.; Batenburg, K.J.; Van Tendeloo, G. |
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Title |
Assisted spray pyrolysis production and characterisation of ZnO nanoparticles with narrow size distribution |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Journal of nanoparticle research |
Abbreviated Journal |
J Nanopart Res |
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Volume |
12 |
Issue |
2 |
Pages |
615-622 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Nano-sized ZnO particles with a narrow size distribution and high crystallinity were prepared from aqueous solutions with high concentrations of Zn2+ containing salts and citric acid in a conventional spray pyrolysis setup. Structure, morphology and size of the produced material were compared to ZnO material produced by simple spray pyrolysis of zinc nitrates in the same experimental setup. Using transmission electron microscopy and electron tomography it has been shown that citric acid-assisted spray pyrolysed material is made up of micron sized secondary particles comprising a shell of lightly agglomerated, monocrystalline primary ZnO nanoparticles with sizes in the 2030 nm range, separable by a simple ultrasonic treatment step. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
S.l. |
Editor |
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Language |
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Wos |
000275318700025 |
Publication Date |
2009-04-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1388-0764;1572-896X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.02 |
Times cited |
27 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.02; 2010 IF: 3.253 |
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Call Number |
UA @ lucian @ c:irua:81771 |
Serial |
156 |
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Permanent link to this record |
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Author |
Esken, D.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Fischer, R.A. |
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Title |
Au@ZIFs: stabilization and encapsulation of cavity-size matching gold clusters inside functionalized Zeolite Imidazolate Frameworks, ZIFs |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
22 |
Issue |
23 |
Pages |
6393-6401 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The selective formation and stabilization of very small, naked metal particles inside the cavities of metal organic frameworks (MOFs) and the simultaneous realization of an even distribution of the particles throughout the crystalline MOF host matrix over a wide range of metal loading are challenging goals. MOFs reveal high specific surface areas, tunable pore sizes, and organic linkers, which are able to interact with guests. The chemically very robust zeolite imidazolate frameworks (ZIFs) are a subclass of MOFs. We chose the microporous sodalite-like ZIF-8 (Zn(MelM)(2); IM = imidazolate) and ZIF-90 (Zn(ICA)(2); ICA = imidazolate-2-carboxyaldehyde) as host matrices to influence the dispersion of imbedded gold nanoparticles (Au NPs). The metal loading was achieved via gas phase infiltration of [Au(CO)Cl] followed by a thermal hydrogenation step to form the Au NPs. Low-dose high-resolution transmission electron microscopy ((HR)TEM) and electron tomography reveal a homogeneous distribution of Au NPs throughout the ZIF matrix. The functional groups of ZIF-90 direct the anchoring of intermediate Au species and stabilize drastically smaller and quite monodisperse Au NPs in contrast to the parent not functionalized ZIF-8. The particles can be very small, match the cavity size and approach defined molecular clusters of magic numbers, i.e., Au(55), independently from the level of loading. Post-synthetic oxidation of the aldehyde groups to yield alkyl esters by the adjacent, catalytically active metal NPs is presented as a new concept of encapsulating nanoparticles inside MOFs and allows multiple steps of metal loadings without decomposition of the MOF. |
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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 |
000284975100025 |
Publication Date |
2010-11-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
194 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
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Call Number |
UA @ lucian @ c:irua:95530 |
Serial |
208 |
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Permanent link to this record |
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Author |
Yang, T.; Perkisas, T.; Hadermann, J.; Croft, M.; Ignatov, A.; Greenblatt, M. |
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Title |
B-site ordered perovskite LaSrMnNbO6 : synthesis, structure and antiferromagnetism |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
183 |
Issue |
11 |
Pages |
2689-2694 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LaSrMnNbO6 has been synthesized by high temperature solid state reaction under 1% H2/Ar dynamic flow. The structure is determined by Rietveld refinement of the powder X-ray diffraction data. It crystallizes in the monoclinic space group P21/n with the unit cell parameters: a=5.69187(12), b=5.74732(10), c=8.07018(15) Å and β=90.0504(29)°, which were also confirmed by electron diffraction. The Mn2+ and Nb5+ ions, whose valence states are confirmed by X-ray absorption near-edge spectroscopy, are almost completely ordered over the B-site (<1% inversion) of the perovskite structure due to the large differences of both cationic size (0.19 Å) and charge. The octahedral framework displays significant tilting distortion according to Glazers tilt system a−b−c+. Upon heating, LaSrMnNbO6 decomposes at 690 °C under O2 flow or at 775 °C in air. The magnetic susceptibility data indicate the presence of long-range antiferromagnetic ordering at TN=8 K; the experimentally observed effective paramagnetic moment, μeff=5.76 μB for high spin Mn2+ (3d5, S=5/2) is in good agreement with the calculated value (μcalcd=5.92 μB). |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
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Language |
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Wos |
000284179800028 |
Publication Date |
2010-09-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
13 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.299; 2010 IF: 2.261 |
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Call Number |
UA @ lucian @ c:irua:85805 |
Serial |
212 |
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Permanent link to this record |
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Author |
Zhao, Q.; Lorenz, H.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Rameshan, C.; Klötzer, B.; Konzett, J.; Penner, S. |
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Title |
Catalytic characterization of pure SnO2 and GeO2 in methanol steam reforming |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Applied catalysis : A : general |
Abbreviated Journal |
Appl Catal A-Gen |
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Volume |
375 |
Issue |
2 |
Pages |
188-195 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Structural changes of a variety of different SnO, SnO2 and GeO2 catalysts upon reduction in hydrogen were correlated with associated catalytic changes in methanol steam reforming. Studied systems include SnO, SnO2 and GeO2 thin film model catalysts prepared by vapour phase deposition and growth on polycrystalline NaCl surfaces and, for comparison, the corresponding pure oxide powder catalysts. Reduction of both the SnO2 thin film and powder at around 673 K in 1 bar hydrogen leads to a substantial reduction of the bulk structure and yields a mixture of SnO2 and metallic β-Sn. On the powder catalyst this transformation is fully reversible upon oxidation in 1 bar O2 at 673 K. Strongly reduced thin films, however, can only be re-transformed to SnO2 if the reduction temperature did not exceed 573 K. For GeO2, the situation is more complex due to its polymorphism. Whereas the tetragonal phase is structurally stable during reduction, oxidation or catalytic reaction, a small part of the hexagonal phase is always transformed into the tetragonal at 673 K independent of the gas phase used. SnO2 is highly active and CO2 selective in methanol steam reforming, but the initial high activity drops considerably upon reduction between 373 and 573 K and almost complete catalyst deactivation is observed after reduction at 673 K, which is associated with the parallel formation of β-Sn. In close correlation to the structural results, the catalytic activity and selectivity can be restored upon an oxidative catalyst regeneration at 673 K. Tetragonal GeO2 exhibits only a small activity and no pronounced selectivity to either CO or CO2, at least after reduction. In its fully oxidized state release of surface/lattice oxygen results in a non-catalytic formation of CO2 by oxidation of CO originating from catalytic dehydrogenation. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000275580600002 |
Publication Date |
2010-01-15 |
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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 |
0926-860X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.339 |
Times cited |
20 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.339; 2010 IF: 3.384 |
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Call Number |
UA @ lucian @ c:irua:81741 |
Serial |
292 |
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Permanent link to this record |
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Author |
Adamson, P.; Hadermann, J.; Smura, C.F.; Rutt, O.J.; Hyett, G.; Free, D.G.; Clarke, S.J. |
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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 |
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Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
24 |
Issue |
14 |
Pages |
2802-2816 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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. |
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Corporate Author |
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Place of Publication |
Washington, D.C. |
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Language |
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Wos |
000306674200024 |
Publication Date |
2012-06-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
11 |
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:100839 |
Serial |
435 |
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Permanent link to this record |
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Author |
Klimczuk, T.; Wang, C.H.; Lawrence, J.M.; Xu, Q.; Durakiewicz, T.; Ronning, F.; Llobet, A.; Trouw, F.; Kurita, N.; Tokiwa, Y.; Lee, H.o.; Booth, C.H.; Gardner, J.S.; Bauer, E.D.; Joyce, J.J.; Zandbergen, H.W.; Movshovich, R.; Cava, R.J.; Thompson, J.D.; |
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Title |
Crystal fields, disorder, and antiferromagnetic short-range order in Yb0.24Sn0.76Ru |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
84 |
Issue |
7 |
Pages |
075152-075152,8 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report extensive measurements on a new compound (Yb0.24Sn0.76)Ru that crystallizes in the cubic CsCl structure. Valence-band photoemission (PES) and L3 x-ray absorption show no divalent component in the 4f configuration of Yb. Inelastic neutron scattering (INS) indicates that the eight-fold degenerate J-multiplet of Yb3+ is split by the crystalline electric field (CEF) into a Γ7-doublet ground state and a Γ8 quartet at an excitation energy 20 meV. The magnetic susceptibility can be fit very well by this CEF scheme under the assumption that a Γ6-excited state resides at 32 meV; however, the Γ8/Γ6 transition expected at 12 meV was not observed in the INS. The resistivity follows a Bloch-Grüneisen law shunted by a parallel resistor, as is typical of systems subject to phonon scattering with no apparent magnetic scattering. All of these properties can be understood as representing simple local moment behavior of the trivalent Yb ion. At 1 K there is a peak in specific heat that is too broad to represent a magnetic-phase transition, consistent with absence of magnetic reflections in neutron diffraction. On the other hand this peak also is too narrow to represent the Kondo effect in the Γ7-doublet ground state. On the basis of the field dependence of the specific heat, we argue that antiferromagnetic (AF) short-range order (SRO) (possibly coexisting with Kondo physics) occurs at low temperatures. The long-range magnetic order is suppressed because the Yb site occupancy is below the percolation threshold for this disordered compound. |
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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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Wos |
000293830800003 |
Publication Date |
2011-08-15 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
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Call Number |
UA @ lucian @ c:irua:92427 |
Serial |
555 |
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Permanent link to this record |
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Author |
Klimczuk, T.; Wang, C.H.; Xu, Q.; Lawrence, J.; Durakiewicz, T.; Ronning, F.; Llobet, A.; Bauer, E.D.; Griveau, J.-C.; Sadowski, W.; Zandbergen, H.W.; Thompson, J.D.; Cava, R.J. |
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Title |
Crystal growth of CsCl-type Yb0.24Sn0.76Ru |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of crystal growth |
Abbreviated Journal |
J Cryst Growth |
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Volume |
318 |
Issue |
1 |
Pages |
1005-1008 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The YbRuSn ternary system was investigated and a new material, Yb0.24Sn0.76Ru, with a simple cubic crystal structure, was discovered. Yb0.24Sn0.76Ru has a smaller lattice parameter a=3.217(4) Å, than its isostructural YbRu analogue (a=3.360 Å). Both X-ray diffraction and electron microscopy techniques were used to refine the crystal structure of Yb0.24Sn0.76Ru. It was found that a new compound forms in the CsCl structure, with Ru on the 1a site and a (Yb, Sn) mixture on site 1b. The XRD Rietveld analysis provides the occupation of Yb equal to 0.24, in agreement with the single crystal nano-electron diffraction refinement, which gives the occupation 0.21. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000289653900220 |
Publication Date |
2010-10-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-0248; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.751 |
Times cited |
1 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 1.751; 2011 IF: 1.726 |
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Call Number |
UA @ lucian @ c:irua:89966 |
Serial |
556 |
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Permanent link to this record |
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Author |
Barreca, D.; Gasparotto, A.; Maccato, C.; Tondello, E.; Lebedev, O.I.; Van Tendeloo, G. |
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Title |
CVD of copper oxides from a \beta-diketonate diamine precursor: tailoring the nano-organization |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
9 |
Issue |
5 |
Pages |
2470-2480 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A copper(II) hexafluoroacetylacetonate (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate, hfa) adduct with N,N,N¡ä,N¡ä-tetramethylethylenediamine (TMEDA) [Cu(hfa)2¡¤TMEDA] is used for the first time as precursor for the chemical vapor deposition (CVD) of copper oxide nanosystems. The syntheses are carried out under both O2 and O2+H2O reaction atmospheres on Si(100) substrates, at temperatures ranging between 250 and 550 ¡ãC. Subsequently, the interrelations between the preparative conditions and the system composition, nanostructure, and morphology are elucidated by means of complementary analytical techniques [Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron and X-ray excited auger electron spectroscopies (XPS and XE-AES), glancing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM)]. The obtained data revealed a gradual transformation from Cu2O, to Cu2O + CuO, to CuO nanosystems upon increasing the deposition temperature from 250 to 550 ¡ãC under both growth atmospheres. Such a phenomenon was accompanied by a progressive morphological evolution from continuous films to 1D hyperbranched nanostructures. Water vapor introduction in the deposition environment enabled to lower the deposition temperature and resulted in a higher aggregate interconnection, attributed to a higher density of nucleation centers. |
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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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Wos |
000265892200066 |
Publication Date |
2009-05-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
60 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2009 IF: 4.162 |
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Call Number |
UA @ lucian @ c:irua:77053 |
Serial |
597 |
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Permanent link to this record |
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Author |
Turner, S.; Lebedev, O.I.; Shenderova, O.; Vlasov, I.I.; Verbeeck, J.; Van Tendeloo, G. |
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Title |
Determination of size, morphology, and nitrogen impurity location in treated detonation nanodiamond by transmission electron microscopy |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
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Volume |
19 |
Issue |
13 |
Pages |
2116-2124 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Size, morphology, and nitrogen impurity location, all of which are all thought to be related to the luminescent properties of detonation nanodiamonds, are determined in several detonation nanodiamond samples using a combination of transmission electron microscopy techniques. Results obtained from annealed and cleaned detonation nanodiamond samples are compared to results from conventionally purified detonation nanodiamond. Detailed electron energy loss spectroscopy combined with model-based quantification provides direct evidence for the sp3 like embedding of nitrogen impurities into the diamond cores of all the studied nanodiamond samples. Simultaneously, the structure and morphology of the cleaned detonation nanodiamond particles are studied using high resolution transmission electron microscopy. The results show that the size and morphology of detonation nanodiamonds can be modified by temperature treatment and that by applying a special cleaning procedure after temperature treatment, nanodiamond particles with clean facets almost free from sp2 carbon can be prepared. These clean facets are clear evidence that nanodiamond cores are not necessarily in coexistence with a graphitic shell of non-diamond carbon. |
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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 |
000268297800012 |
Publication Date |
2009-05-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616-301X;1616-3028; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.124 |
Times cited |
100 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 12.124; 2009 IF: 6.990 |
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Call Number |
UA @ lucian @ c:irua:78261UA @ admin @ c:irua:78261 |
Serial |
674 |
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Permanent link to this record |
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Author |
Turner, S.; Lebedev, O.I.; Schroeder, F.; Fischer, R.A.; Van Tendeloo, G. |
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Title |
Direct imaging of loaded metal-organic framework materials (metal@MOF-5) |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
20 |
Issue |
17 |
Pages |
5622-5627 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We illustrate the potential of advanced transmission electron microscopy for the characterization of a new class of soft porous materials: metal@Zn4O(bdc)3 (metal@MOF-5; bdc = 1,4-benzenedicarboxylate). By combining several electron microscopy techniques (transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), electron diffraction (ED), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and electron tomography) and by carefully reducing the electron dose to avoid beam damage, it is possible to simultaneously characterize the MOF-5 framework material and the loaded metal nanoparticles. We also demonstrate that electron tomography can be used to accurately determine the position and distribution of the particles within the MOF-5 framework. To demonstrate the implementation of these microscopy techniques and what kind of results can be expected, measurements on gas-phase-loaded metal−organic framework materials Ru@MOF-5 and Pd@MOF-5 are presented. |
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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 |
000258941400021 |
Publication Date |
2008-08-07 |
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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 |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
112 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2008 IF: 5.046 |
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Call Number |
UA @ lucian @ c:irua:76595 |
Serial |
714 |
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Permanent link to this record |
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Author |
Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Guitián, F.; Yoshimura, M. |
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Title |
An effective morphology control of hydroxyapatite crystals via hydrothermal synthesis |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
9 |
Issue |
1 |
Pages |
466-474 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A facile urea-assisted hydrothermal synthesis and systematic characterization of hydroxyapatite (HA) with calcium nitrate tetrahydrate and diammonium hydrogen phosphate as precursors are reported. The advantage of the proposed technique over previously reported synthetic approaches is the simple but precise control of the HA crystals morphology, which is achieved by employing an intensive, stepwise, and slow thermal decomposition of urea as well as varying initial concentrations of starting reagents. Whereas the plate-, hexagonal prism- and needle-like HA particles preferentially growth along the c-axis, the smaller and fine-plate-like HA crystals demonstrate crystal growth along the (102) and (211) directions, uncommon for HA. Furthermore, it was established that the hydrothermally derived powdered products are phase-pure HA containing CO32− anions in the crystal lattice, that is, AB-type carbonated hydroxyapatite. Transmission electron microscopy (TEM) and electron diffraction (ED) of selected samples reveal that the as-prepared HA crystals are single-crystalline and exhibit a nearly defect-free microstructure. The hardness and elastic modulus of the hexagonal prism-like HA crystals have been investigated on a nanoscale using the nanoindentation technique; the observed trends are discussed. |
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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 |
000262332700073 |
Publication Date |
2008-11-21 |
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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 |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
183 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2009 IF: 4.162 |
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Call Number |
UA @ lucian @ c:irua:75740 |
Serial |
853 |
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Permanent link to this record |
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Author |
Moshnyaga, V.; Gehrke, K.; Sudheendra, L.; Belenchuk, A.; Raabe, S.; Shapoval, O.; Verbeeck, J.; Van Tendeloo, G.; Samwer, K. |
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Title |
Electrical nonlinearity in colossal magnetoresistance manganite films: relevance of correlated polarons |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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Volume |
79 |
Issue |
13 |
Pages |
134413,1-134413,8 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The metal-insulator (MI) transition in epitaxial thin films of La0.75Ca0.25MnO3 (LCMO) is accompanied by the appearance of an intrinsic electrical nonlinearity. The latter, probed by electrical third harmonic voltage, U3, or resistance, R3=dU3/dJ, is drastically enhanced in the vicinity of the MI transition, TMI=267 K. Applied magnetic field, B=5 T, suppresses the nonlinearity, resulting in a huge nonlinear CMR3(TMI)~105%. R3 shows a peculiar low-frequency (1 kHz) dependence, R3~(-0)n, with exponent, n, changing across the MI transition from n~1,52 for TTMI to n=1 (T<TMI). The observed electrical nonlinearity in LCMO reflects the behavior of correlated polarons, the number of which dramatically enhances in the vicinity of TMI. We argued that correlated polarons, considered as electric-elastic quadrupoles, provide a nonlinear (quadratic) coupling to the electric field, yielding a third harmonic electric nonlinearity in LCMO. The reference film of La0.7Sr0.3MnO3 (LSMO), a prototypic double exchange system with second-order phase transition, is characterized as a linear metallic material in the whole range of temperatures (T=10400 K), magnetic fields (B=05 T), and frequencies (=11000 Hz). |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000265942800074 |
Publication Date |
2009-04-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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Call Number |
UA @ lucian @ c:irua:77022UA @ admin @ c:irua:77022 |
Serial |
893 |
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Permanent link to this record |
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Author |
Müller, M.; Lebedev, O.I.; Fischer, R.A. |
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Title |
Gas-phase loading of [Zn4O(btb)2] (MOF-177) with organometallic CVD-precursors: inclusion compounds of the type [LnM]a@MOF-177 and the formation of Cu and Pd nanoparticles inside MOF-177 |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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Volume |
18 |
Issue |
43 |
Pages |
5274-5281 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The highly porous and desolvated (activated) coordination polymer [Zn4O(btb)2] (btb = benzene-1,3,5-tribenzoate; MOF-177) was loaded with the organometallic compounds [Cp2Fe], [Cp*2Zn], [Cu(OCHMeCH2NMe2)2], [CpCuL] (L = PMe3, CNtBu) and [CpPd(3-C3H5)] via solvent-free adsorption from the gas-phase. The inclusion compounds of the type [LnM]a@MOF-177, where [LnM] indicates the respective compound and the parameter a denotes the number of molecules per formula unit of the MOF-177, were characterised by elemental analysis, FT-IR, solid-state NMR spectroscopy and by powder X-ray diffraction (PXRD). Remarkably high effective loadings of up to 11 molecules [Cp2Fe] and 10 molecules [CpPd(3-C3H5)] per cavity were determined. The analytical data prove that the host lattice and the guest molecules interact only by weak van-der-Waals forces without any significant change of the framework or the chemical nature of the included molecules. Cu nanoparticles showing the typical surface plasmon resonance at 580 nm and Pd nanoparticles of about 2.6 nm in size were formed inside the cavities of MOF-177 by the thermally activated hydrogenolysis of the inclusion compounds [CpCuCNtBu]2@MOF-177 and by photolysis of [CpPd(3-C3H5)]10@MOF-177 in an inert atmosphere (Ar). PXRD, FT-IR and NMR studies revealed that the MOF-177 matrix remained unchanged during the decomposition process of the precursors. N2 adsorption studies of the obtained materials Cu@MOF-177 (e.g. 10.6 wt.% Cu, 2309 m2 g-1) and Pd@MOF-177 (e.g. 32.5 wt.%, 1063 m2 g-1) reveal high remaining specific surface areas (Langmuir model). |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000260487300015 |
Publication Date |
2008-10-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0959-9428;1364-5501; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
65 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:75699 |
Serial |
1318 |
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Permanent link to this record |
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Author |
Bekermann, D.; Gasparotto, A.; Barreca, D.; Bovo, L.; Devi, A.; Fischer, R.A.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G. |
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Title |
Highly oriented ZnO nanorod arrays by a novel plasma chemical vapor deposition process |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
10 |
Issue |
4 |
Pages |
2011-2018 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Strongly c-axis oriented ZnO nanorod arrays were grown on Si(100) by plasma enhanced-chemical vapor deposition (PE-CVD) starting from two volatile bis(ketoiminato) zinc(II) compounds Zn[(R′)NC(CH3)═C(H)C(CH3)═O]2, with R′ = -(CH2)xOCH3 (x = 2, 3). A systematic investigation of process parameters enabled us to obtain the selective formation of ZnO nanorods with tailored features, and provided an important insight into their growth mechanism. The morphology, structure, and composition of the synthesized ZnO nanosystems were thoroughly analyzed by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Photoluminescence (PL) measurements were carried out to gain information on the optical properties. Specifically, one-dimensional (1D) ZnO architectures could be grown on Si(100) substrates at temperatures as low as 200−300 °C and radio frequency (RF)-power values of 20 W, provided that a sufficiently high mass supply to the growth surface was maintained. To the best of our knowledge, the present work reports the mildest preparation conditions ever appeared in the literature for the PE-CVD of ZnO nanorods, a key result in view of potential large-scale technological applications. |
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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 |
000276234500080 |
Publication Date |
2010-03-18 |
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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 |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
75 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2010 IF: 4.390 |
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Call Number |
UA @ lucian @ c:irua:82311 |
Serial |
1472 |
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Permanent link to this record |
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Author |
Lebedev, O.I.; Caignaert, V.; Raveau, B.; Pop, N.; Gozzo, F.; Van Tendeloo, G.; Pralong, V. |
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Title |
HRTEM and neutron diffraction study of LixMo5O17 : from the ribbon (x=5) structure to the rock salt (x=12) structure |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
184 |
Issue |
4 |
Pages |
790-796 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Structure determination of the fully intercalated phase Li12Mo5O17 and of the deintercalated oxide Li5Mo5O17 has been carried out by electron microscopy and neutron powder diffraction. The reversible topotactic transformation between the ordered rock salt structure of the former and the ribbon structure of the latter (closely related to that of Li4Mo5O17) is explained on the following basis: both structures can be described as strips built up as an assembly of infinite ribbons of MoO6 octahedra that are five octahedra thick, and that differ by slight displacements of the octahedral ribbons. We show that the electrochemical behavior of the LixMo5O17 system is based on two sorts of Li+ sites; those that are located within the strips between the ribbons, and those that are located at the border of the strips. The high rate of Li intercalation in this oxide and its reversibility are discussed in terms of its peculiar structure. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000289597100010 |
Publication Date |
2011-02-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
1 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.299; 2011 IF: 2.159 |
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Call Number |
UA @ lucian @ c:irua:88646 |
Serial |
1515 |
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Permanent link to this record |
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Author |
Malo, S.; Lepoittevin, C.; Pérez, O.; Hébert, S.; Van Tendeloo, G.; Hervieu, M. |
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Title |
Incommensurate crystallographic shear structures and magnetic properties of the cation deficient perovskite (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29 |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
22 |
Issue |
5 |
Pages |
1788-1797 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The origin of the incommensurability in the crystallographic shear (CS) structure of the ferri-Manganite (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29, related to the cation deficient perovskite, has been determined by careful analysis of the boundaries between the two variants constituting the phasoid. High Resolution Electron Microscopy/HAADF-STEM images allow the structural mechanisms to be understood through the presence of structural units common to both phases, responsible of the incommensurate character observed in the electron diffraction patterns. The structural analysis allows for identifying different types of CS phases in the Pb−Sr−Fe(Mn)−O diagram and shows that the stabilization of the six-sided tunnels requires a higher A/B cationic ratio. A description of these phases is proposed through simple structural building units (SBU), based on chains of octahedra bordered by two pyramids. The (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29 CS compound exhibits a strong antiferromagnetic and insulating behavior, similar to the Fe-2201 and terrace ferrites but differs by the presence of a hysteresis, with a small coercive field. |
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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 |
000274929000025 |
Publication Date |
2010-01-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
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Call Number |
UA @ lucian @ c:irua:81800 |
Serial |
1593 |
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Permanent link to this record |
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Author |
Lepoittevin, C.; Malo, S.; Barrier, N.; Nguyen, N.; Van Tendeloo, G.; Hervieu, M. |
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Title |
Long-range ordering in the Bi1-xAexFeO3-x/2 perovskites: Bi1/3Sr2/3FeO2.67 and Bi1/2Ca1/2FeO2.75 |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
181 |
Issue |
10 |
Pages |
2601-2609 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Two-ordered perovskites, Bi1/3Sr2/3FeO2.67 and Bi1/2Ca1/2FeO2.75, have been stabilized and characterized by transmission electron microscopy, Mössbauer spectroscopy and X-ray powder diffraction techniques. They both exhibit orthorhombic superstructures, one with a≈b≈2ap and c≈3ap (S.G.: Pb2n or Pbmn) for the Sr-based compound and one with a≈b≈2ap and c≈8ap (S.G.: B222, Bmm2, B2mm or Bmmm) for the Ca-based one. The high-resolution transmission electron microscopy (HRTEM) images evidence the existence of one deficient [FeOx]∞ layer, suggesting that Bi1/3Sr2/3FeO2.67 and Bi1/2Ca1/2FeO2.75 behave differently compared to their Ln-based homolog. The HAADF-STEM images allow to propose a model of cation ordering on the A sites of the perovskite. The Mössbauer analyses confirm the trivalent state of iron and its complex environment with three types of coordination. Both compounds exhibit a high value of resistivity and the inverse molar susceptibility versus temperature curves evidence a magnetic transition at about 730 K for the Bi1/3Sr2/3FeO2.67 and a smooth reversible transition between 590 and 650 K for Bi1/2Ca1/2FeO2.75. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000260441000008 |
Publication Date |
2008-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
27 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.299; 2008 IF: 1.910 |
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Call Number |
UA @ lucian @ c:irua:75663 |
Serial |
1839 |
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Permanent link to this record |
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Author |
Biermans, E.; Molina, L.; Batenburg, K.J.; Bals, S.; Van Tendeloo, G. |
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Title |
Measuring porosity at the nanoscale by quantitative electron tomography |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
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Volume |
10 |
Issue |
12 |
Pages |
5014-5019 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Quantitative electron tomography is proposed to characterize porous materials at a nanoscale. To achieve reliable three-dimensional (3D) quantitative information, the influence of missing wedge artifacts and segmentation methods is investigated. We are presenting the Discrete Algebraic Reconstruction Algorithm as the most adequate tomography method to measure porosity at the nanoscale. It provides accurate 3D quantitative information, regardless the presence of a missing wedge. As an example, we applied our approach to nanovoids in La2Zr2O7 thin films. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington |
Editor |
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Language |
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Wos |
000284990900040 |
Publication Date |
2010-11-22 |
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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 |
1530-6984;1530-6992; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.712 |
Times cited |
79 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 12.712; 2010 IF: 12.219 |
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Call Number |
UA @ lucian @ c:irua:87658 |
Serial |
1967 |
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Permanent link to this record |
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Author |
Meilikhov, M.; Yusenko, K.; Esken, D.; Turner, S.; Van Tendeloo, G.; Fischer, R.A. |
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Title |
Metals@MOFs – loading MOFs with metal nanoparticles for hybrid functions |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
European journal of inorganic chemistry |
Abbreviated Journal |
Eur J Inorg Chem |
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Volume |
2010 |
Issue |
24 |
Pages |
3701-3714 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Metalorganic frameworks (MOFs) as well as porous coordination polymers (PCPs) are porous, organicinorganic hybrid solids with zeolite-like structures and properties. Due to their extraordinarily high surface area and well defined pore structure MOFs can be used for the stabilization of metal nanoparticles with adjustable size. The embedded metal nanoparticles are still accessible for other reagents due to the high porosity of the MOF systems. This fact makes metal@MOF systems especially interesting for heterogeneous catalysis, gas storage and chemical sensing. This review compiles the cases of metal nanoparticles supported by or embedded into MOFs reported so far and the main aspects and problems associated with these novel nanocomposite systems. The determination of the dispersion and the location of the particles at the MOF support, the control of the loading degree and its effect on the catalytic activity of the system are discussed as well as the partial degradation of the MOF structure upon particle formation. Examples of the introduction of stabilizing groups into the MOF network that direct the loading and can influence the size and shape of the embedded particles are still rare and point into the possible direction of future investigations. Finally, the formation of bimetallic nanoparticles, which are stabilized and supported by a MOF network, will also be reviewed. |
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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 |
000281684300001 |
Publication Date |
2010-07-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-1948; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.444 |
Times cited |
366 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.444; 2010 IF: 2.910 |
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Call Number |
UA @ lucian @ c:irua:85495 |
Serial |
2014 |
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Permanent link to this record |
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Author |
Caignaert, V.; Abakumov, A.M.; Pelloquin, D.; Pralong, V.; Maignan, A.; Van Tendeloo, G.; Raveau, B. |
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Title |
A new mixed-valence ferrite with a cubic structure, YBaFe4O7: spin-glass-like behavior |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
21 |
Issue |
6 |
Pages |
1116-1122 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A new mixed-valence ferrite, YBaFe4O7, has been synthesized. Its unique cubic structure, with a = 8.9595(2) Å, is closely related to that of the hexagonal 114 oxides YBaCo4O7 and CaBaFe4O7. It consists of corner-sharing FeO4 tetrahedra, forming triangular and kagome layers parallel to (111)C. In fact, the YBaFe4O7 and CaBaFe4O7 structures can be described as two different ccc and chch close packings of [BaO3]∞ and [O4]∞ layers, respectively, whose tetrahedral cavities are occupied by Fe2+/Fe3+ cations. The local structure of YBaFe4O7 is characterized by a large amount of stacking faults originating from the presence of hexagonal layers in the ccc cubic close-packed YBaFe4O7 structure. In this way, they belong to the large family of spinels and hexagonal ferrites studied for their magnetic properties. Differently from all the ferrites and especially from CaBaFe4O7, which are ferrimagnetic, YBaFe4O7 is an insulating spin glass with Tg = 50 K. |
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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 |
000264310900019 |
Publication Date |
2009-02-25 |
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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 |
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Impact Factor |
9.466 |
Times cited |
39 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2009 IF: 5.368 |
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Call Number |
UA @ lucian @ c:irua:76432 |
Serial |
2325 |
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Permanent link to this record |