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Records |
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Author |
Shetty, S.; Sinha, S.K.; Ahmad, R.; Singh, A.K.; Van Tendeloo, G.; Ravishankar, N. |
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Title |
Existence of Ti2+States on the Surface of Heavily Reduced SrTiO3Nanocubes |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
|
Issue |
|
Pages |
acs.chemmater.7b04113 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Using advanced electron microscopy, we demonstrate the presence of Ti2+ on the 001 surfaces of heavily reduced strontium titanate nanocubes. While high-angle annular dark field images show a clear difference between the surfaces of the unreduced and reduced samples, electron energy loss spectroscopy detects the presence of Ti2+ on the surface of the reduced cubes. Conventional reduction only leads to the formation of Ti3+ and involves the use of high temperatures. In our case, reduction is achieved at relatively lower temperatures in the solid state using sodium borohydride as the reducing agent. Our findings provide insights into the optical properties of the samples and provide a convenient method to produce highly reduced surfaces that could demonstrate a range of exotic physical phenomena |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000418206600005 |
Publication Date |
2017-11-17 |
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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 |
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 |
8 |
Open Access |
OpenAccess |
|
Notes |
We thank Advanced Facility for Microscopy and Microanalysis (AFMM), IISc, Bangalore for providing the TEM facility. We also thank MNCF, CeNSE, IISc for providing the XPS and FT-IR facilities. We acknowledge the help from Prof. Anshu Pandey for providing the PL facility and Mr. Ashutosh Gupta for the help with measurements. SS and NR thank DST for providing the financial support. RA and AKS acknowledge Super Computing Education and Research Center (SERC) and Materials Research Center (MRC), at IISc for providing required computational facilities. RA acknowledges the financial support from INSPIRE fellowship, AORC.Science and Engineering Research Board; Federaal Wetenschapsbeleid; Department of Science and Technology, Ministry of Science and Technology; |
Approved |
Most recent IF: 9.466 |
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Call Number |
UA @ lucian @c:irua:147191 |
Serial |
4767 |
Permanent link to this record |
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Author |
Hamelet, S.; Casas-Cabanas, M.; Dupont, L.; Davoisne, C.; Tarascon, J.M.; Masquelier, C. |
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Title |
Existence of superstructures due to large amounts of Fe vacancies in the LiFePO4-type framework |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
23 |
Issue |
1 |
Pages |
32-38 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LiFePO4 has been under intense scrutiny over the past decade because it stands as an attractive positive electrode material for the next generation of Li-ion batteries to power electric vehicles and hybrid electric vehicles, hence the importance of its thermal behavior. The reactivity of LiFePO4 with air at moderate temperatures is shown to be dependent on its particle size. For nanosized materials, a progressive displacement of Fe from the core structure leading to a composite made of nanosize Fe2O3 and highly defective, oxidized LixFeyPO4 compositions, among which the “ideal” formula LiFe2/3PO4. Herein we report, from both temperature-controlled X-ray diffraction and electronic diffraction microscopy, that these off-stoichiometry olivine-type compounds show a defect ordering resulting in the formation of a superstructure. Such a finding shows striking similarities with the temperature-driven oxidation of fayalite Fe2SiO4 (another olivine) to structurally defective laihunite, reported in the literature three decades ago. |
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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 |
000285726900007 |
Publication Date |
2010-12-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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 |
30 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
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Call Number |
UA @ lucian @ c:irua:105605 |
Serial |
1130 |
Permanent link to this record |
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Author |
Brodu, A.; Ballottin, M.V.; Buhot, J.; van Harten, E.J.; Dupont, D.; La Porta, A.; Prins, P.T.; Tessier, M.D.; Versteegh, M.A.M.; Zwiller, V.; Bals, S.; Hens, Z.; Rabouw, F.T.; Christianen, P.C.M.; de Donega, C.M.; Vanmaekelbergh, D. |
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Title |
Exciton Fine Structure and Lattice Dynamics in InP/ZnSe Core/Shell Quantum Dots |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
ACS Photonics |
Abbreviated Journal |
Acs Photonics |
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Volume |
5 |
Issue |
5 |
Pages |
3353-3362 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Nanocrystalline InP quantum dots (QDs) hold promise for heavy-metal-free optoelectronic applications due to their bright and size tunable emission in the visible range. Photochemical stability and high photoluminescence (PL) quantum yield are obtained by a diversity of epitaxial shells around the InP core. To understand and optimize the emission line shapes, the exciton fine structure of InP core/shell QD systems needs be investigated. Here, we study the exciton fine structure of InP/ZnSe core/shell QDs with core diameters ranging from 2.9 to 3.6 nm (PL peak from 2.3 to 1.95 eV at 4 K). PL decay measurements as a function of temperature in the 10 mK to 300 K range show that the lowest exciton fine structure state is a dark state, from which radiative recombination is assisted by coupling to confined acoustic phonons with energies ranging from 4 to 7 meV, depending on the core diameter. Circularly polarized fluorescence line-narrowing (FLN) spectroscopy at 4 K under high magnetic fields (up to 30 T) demonstrates that radiative recombination from the dark F = +/- 2 state involves acoustic and optical phonons, from both the InP core and the ZnSe shell. Our data indicate that the highest intensity FLN peak is an acoustic phonon replica rather than a zero-phonon line, implying that the energy separation observed between the F = +/- 1 state and the highest intensity peak in the FLN spectra (6 to 16 meV, depending on the InP core size) is larger than the splitting between the dark and bright fine structure exciton states. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000442185900049 |
Publication Date |
2018-07-18 |
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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 |
2330-4022 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.756 |
Times cited |
40 |
Open Access |
OpenAccess |
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Notes |
; We acknowledge the support of the HFML-RU/FOM, member of the European Magnetic Field Laboratory (EMFL). D.V. and Z.H. acknowledge support by the European Commission via the Marie-Sklodowska Curie action Phonsi (H2020-MSCA-ITN-642656) and the Marie Sklodowska-Curie Action Compass (H2020 MSCA-RISE-691185). Z.H. acknowledges the Research Foundation Flanders (project 17006602) and Ghent University (GOA no. 01G01513). Z.H. and S.B. acknowledge SIM vzw (SBO-QDOCCO). F.T.R. acknowledges financial support from The Netherlands Organisation for Scientific Research NWO (Gravitation program Multiscale Catalytic Energy Conversion and VENI grant number 722.017.002). This work was also supported by the Dutch NWO-Physics Program DDC13, ERC Advanced Grant 692691 “First step”, and ERC Starting Grant 335078 “COLOURATOM”. ; ecas_sara |
Approved |
Most recent IF: 6.756 |
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Call Number |
UA @ lucian @ c:irua:153753UA @ admin @ c:irua:153753 |
Serial |
5100 |
Permanent link to this record |
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Author |
Lebedev, O.I.; Turner, S.; Caignaert, V.; Cherepanov, V.A.; Raveau, B. |
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Title |
Exceptional layered ordering of cobalt and iron in perovskites |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
28 |
Issue |
28 |
Pages |
2907-2911 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000375810400005 |
Publication Date |
2016-04-20 |
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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 |
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 |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466 |
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Call Number |
UA @ lucian @ c:irua:133640 |
Serial |
4178 |
Permanent link to this record |
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Author |
Jin, B.; Zuo, N.; Hu, Z.-Y.; Cui, W.; Wang, R.; Van Tendeloo, G.; Zhou, X.; Zhai, T. |
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Title |
Excellent excitonic photovoltaic effect in 2D CsPbBr₃/CdS heterostructures |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
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Volume |
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Issue |
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Pages |
2006166-2006168 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
P-n photovoltaic junctions are essential building blocks for optoelectronic devices for energy conversion. However, this photovoltaic efficiency has almost reached its theoretical limit. Here, a brand-new excitonic photovoltaic effect in 2D CsPbBr3/CdS heterostructures is revealed. These heterostructures, synthesized by epitaxial growth, display a clean interface and a strong interlayer coupling. The excitonic photovoltaic effect is a function of both the built-in equilibrium electrical potential energy and the chemical potential energy, which is generated by the significant concentration gradient of electrons and holes at the heterojunction interface. Excitingly, this novel photovoltaic effect results in a large open-circuit voltage of 0.76 V and a high power conversion efficiency of 17.5%. In addition, high photodetection performance, including a high photoswitch ratio (I-light/I-dark) of 10(5)and a fast response rate of 23 mu s are obtained. These findings provide a new platform for photovoltaic applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000567829000001 |
Publication Date |
2020-09-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616-301x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
19 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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Notes |
; B.J., N.Z., and Z.Y.H. contributed equally to this work. This work was supported by the National Natural Science Foundation of China (Grant No. 21825103 and 51802103), the Hubei Provincial Natural Science Foundation of China (Grant No. 2019CFA002), and the Fundamental Research Funds for the Central University (Grant No. 2019kfyXMBZ018, WUT: 2019III012GX). Here the authors also thank the support from Analytical and Testing Center in HUST and the State Key Laboratory of Silicate Materials for Architectures in WUT. ; |
Approved |
Most recent IF: 19; 2020 IF: 12.124 |
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Call Number |
UA @ admin @ c:irua:171970 |
Serial |
6514 |
Permanent link to this record |
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Author |
Zelaya, E.; Esquivel, M.R.; Schryvers, D. |
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Title |
Evolution of the phase stability of NiAl under low energy ball milling |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Advanced powder technology |
Abbreviated Journal |
Adv Powder Technol |
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Volume |
24 |
Issue |
6 |
Pages |
1063-1069 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Low energy mechanical alloying of Ni35 at.%Al and Ni40 at.%Al material was performed and the resulting structures were investigated by XRD and TEM. The final intermetallics observed consist of two phases, NiAl(B2) and Ni3Al while 7R and 3R martensite was observed in post-annealed samples. Different integrated milling times were associated to the intermetallic consolidation and initial blend dissociation. |
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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 |
Zeist |
Editor |
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Language |
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Wos |
000339175000024 |
Publication Date |
2013-03-30 |
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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 |
0921-8831; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.659 |
Times cited |
10 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 2.659; 2013 IF: 1.642 |
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Call Number |
UA @ lucian @ c:irua:107345 |
Serial |
1102 |
Permanent link to this record |
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Author |
Fomin, V.M.; Misko, V.R.; Devreese, J.T.; Moshchalkov, V.V. |
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Title |
Evolution of superconducting islands in a square mesoscopic loop |
Type |
A1 Journal article |
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Year |
1996 |
Publication |
Phantoms newsletter |
Abbreviated Journal |
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Volume |
12 |
Issue |
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Pages |
7 |
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Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
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Abstract |
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Address |
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Corporate Author |
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Publisher |
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Place of Publication |
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Wos |
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Publication Date |
0000-00-00 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:16187 |
Serial |
1101 |
Permanent link to this record |
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Author |
Ranjan, R.; Pandey, D.; Schuddinck, W.; Richard, O.; De Meulenaere, P.; van Landuyt, J.; Van Tendeloo, G. |
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Title |
Evolution of crystallographic phases in (Sr1-xCax)TiO3 with composition (x) |
Type |
A1 Journal article |
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Year |
2001 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
162 |
Issue |
1 |
Pages |
20-28 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000172586400003 |
Publication Date |
2002-09-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
45 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.299; 2001 IF: 1.614 |
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Call Number |
UA @ lucian @ c:irua:54711 |
Serial |
1098 |
Permanent link to this record |
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Author |
Augustyns, V.; van Stiphout, K.; Joly, V.; Lima, T.A.L.; Lippertz, G.; Trekels, M.; Menendez, E.; Kremer, F.; Wahl, U.; Costa, A.R.G.; Correia, J.G.; Banerjee, D.; Gunnlaugsson, H.P.; von Bardeleben, J.; Vickridge, I.; Van Bael, M.J.; Hadermann, J.; Araujo, J.P.; Temst, K.; Vantomme, A.; Pereira, L.M.C. |
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Title |
Evidence of tetragonal distortion as the origin of the ferromagnetic ground state in gamma-Fe nanoparticles |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
96 |
Issue |
17 |
Pages |
174410 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
<script type='text/javascript'>document.write(unpmarked('gamma-Fe and related alloys are model systems of the coupling between structure and magnetism in solids. Since different electronic states (with different volumes and magnetic ordering states) are closely spaced in energy, small perturbations can alter which one is the actual ground state. Here, we demonstrate that the ferromagnetic state of gamma-Fe nanoparticles is associated with a tetragonal distortion of the fcc structure. Combining a wide range of complementary experimental techniques, including low-temperature Mossbauer spectroscopy, advanced transmission electron microscopy, and synchrotron radiation techniques, we unambiguously identify the tetragonally distorted ferromagnetic ground state, with lattice parameters a = 3.76(2) angstrom and c = 3.50(2) angstrom, and a magnetic moment of 2.45(5) mu(B) per Fe atom. Our findings indicate that the ferromagnetic order in nanostructured gamma-Fe is generally associated with a tetragonal distortion. This observation motivates a theoretical reassessment of the electronic structure of gamma-Fe taking tetragonal distortion into account.')); |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000414525200005 |
Publication Date |
2017-11-07 |
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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 |
2469-9969; 2469-9950 |
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 |
1 |
Open Access |
OpenAccess |
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Notes |
; The authors thank the Fund for Scientific Research-Flanders, the Concerted Research Action of the KU Leuven (GOA/14/007), the KU Leuven BOF (STRT/14/002), the Hercules Foundation, the Portuguese Foundation for Science and Technology (CERN/FIS-NUC/0004/2015), and the European Union Seventh Framework through ENSAR2 (European Nuclear Science and Applications Research, Project No. 654002), and SPIRIT (Support of Public and Industrial Research Using Ion Beam Technology, Contract No. 227012). We acknowledge the European Synchrotron Radiation Facility (ESRF) for providing beam time (experiments 26-01-1018, 26-01-1057, 20-02-728, HC-1850, HC-2208), as well as C. Baehtz, N. Boudet, and N. Blancand for support during the experiments. We acknowledge the ISOLDE-CERN facility for providing beam time (experiment IS580) and technical assistance. The authors (L.M.C.P., F.K.) acknowledge the facilities and the scientific and technical assistance of the Australian Microscopy & Microanalysis Research Facility at the Centre for Advanced Microscopy, Australian National University. We also acknowledge the contribution of Prof. Mark Ridgway (Australian National University), who passed away before the work was completed. ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:147387 |
Serial |
4873 |
Permanent link to this record |
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Author |
Laffez, P.; Lebedev, O.I.; Ruello, P.; Desfeux, R.; Banerjee, G.; Capon, F. |
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Title |
Evidence of strain induced structural change in hetero-epitaxial NdNiO3 thin films with metal-insulator transition |
Type |
A1 Journal article |
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Year |
2004 |
Publication |
European physical journal: applied physics |
Abbreviated Journal |
Eur Phys J-Appl Phys |
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Volume |
25 |
Issue |
1 |
Pages |
25-31 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Neodymium nickelate thin films have been prepared on NdGaO3 substrates by RF magnetron sputtering and post-annealing treatment under oxygen pressure. Transport properties are found to depend strongly on film thickness. Thick films show transport properties close to bulk ceramics, while very thin films exhibit a large transition from metal to insulator which occurs over a wide temperature range with high resistivity. Structure and surface morphology of the films have been investigated by Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). Thin films (approximate to17 nm) grow heteroepitaxially, while thicker films (approximate to73 nm) show a granular structure. The thinnest sample suggests a symmetry change induced by the epitaxial strain of the substrate. This paper discusses the relationship between microstructure and transport properties. |
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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 |
Paris |
Editor |
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Language |
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Wos |
000187286000003 |
Publication Date |
2003-12-15 |
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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 |
1286-0042;1286-0050; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
0.684 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 0.684; 2004 IF: 0.745 |
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Call Number |
UA @ lucian @ c:irua:103256 |
Serial |
1096 |
Permanent link to this record |
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Author |
Bourgeois, J.; Hervieu, M.; Poienar, M.; Abakumov, A.M.; Elkaïm, E.; Sougrati, M.T.; Porcher, F.; Damay, F.; Rouquette, J.; Van Tendeloo, G.; Maignan, A.; Haines, J.; Martin, C.; |
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Title |
Evidence of oxygen-dependent modulation in LuFe2O4 |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
6 |
Pages |
064102-064120,10 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A polycrystalline sample of LuFe2O4 has been investigated by means of powder synchrotron x-ray and neutron diffraction and transmission electron microscopy (TEM), along with Mössbauer spectroscopy and transport and magnetic properties. A monoclinic distortion is unambiguously evidenced, and the crystal structure is refined in the monoclinic C2/m space group [aM = 5.9563(1) Å, bM = 3.4372(1) Å, cM = 8.6431(1) Å, β = 103.24(1)°]. Along with the previously reported modulations distinctive of the charge-ordering (CO) of the iron species, a new type of incommensurate order is observed, characterized by a vector q⃗1 = α1a⃗M* + γ1c⃗M* (with α1 ≅ 0.55, γ1 ≅ 0.13). In situ heating TEM observations from 300 to 773 K confirm that the satellites associated with q⃗1 vanish completely, only at a temperature significantly higher than the CO temperature. This incommensurate modulation has a displacive character and corresponds primarily to a transverse displacive modulation wave of the Lu cations position, as revealed by the high resolution, high angle annular dark field scanning TEM images and in agreement with synchrotron data refinements. Analyses of vacuum-annealed samples converge toward the hypothesis of a new ordering mechanism, associated with a tiny oxygen deviation from the O4 stoichiometry. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000299896900003 |
Publication Date |
2012-02-06 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.836 |
Times cited |
24 |
Open Access |
|
|
Notes |
Hercules |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
|
Call Number |
UA @ lucian @ c:irua:95042 |
Serial |
1095 |
Permanent link to this record |
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|
|
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Author |
Mao, J.; Milovanović, S.P.; Andelkovic, M.; Lai, X.; Cao, Y.; Watanabe, K.; Taniguchi, T.; Covaci, L.; Peeters, F.M.; Geim, A.K.; Jiang, Y.; Andrei, E.Y. |
|
Title |
Evidence of flat bands and correlated states in buckled graphene superlattices |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Nature |
Abbreviated Journal |
Nature |
|
Volume |
584 |
Issue |
7820 |
Pages |
215-220 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
Abstract |
Two-dimensional atomic crystals can radically change their properties in response to external influences, such as substrate orientation or strain, forming materials with novel electronic structure(1-5). An example is the creation of weakly dispersive, 'flat' bands in bilayer graphene for certain 'magic' angles of twist between the orientations of the two layers(6). The quenched kinetic energy in these flat bands promotes electron-electron interactions and facilitates the emergence of strongly correlated phases, such as superconductivity and correlated insulators. However, the very accurate fine-tuning required to obtain the magic angle in twisted-bilayer graphene poses challenges to fabrication and scalability. Here we present an alternative route to creating flat bands that does not involve fine-tuning. Using scanning tunnelling microscopy and spectroscopy, together with numerical simulations, we demonstrate that graphene monolayers placed on an atomically flat substrate can be forced to undergo a buckling transition(7-9), resulting in a periodically modulated pseudo-magnetic field(10-14), which in turn creates a 'post-graphene' material with flat electronic bands. When we introduce the Fermi level into these flat bands using electrostatic doping, we observe a pseudogap-like depletion in the density of states, which signals the emergence of a correlated state(15-17). This buckling of two-dimensional crystals offers a strategy for creating other superlattice systems and, in particular, for exploring interaction phenomena characteristic of flat bands. Buckled monolayer graphene superlattices are found to provide an alternative to twisted bilayer graphene for the study of flat bands and correlated states in a carbon-based material. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000559831500012 |
Publication Date |
2020-08-12 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0028-0836 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
64.8 |
Times cited |
109 |
Open Access |
Not_Open_Access |
|
Notes |
; ; |
Approved |
Most recent IF: 64.8; 2020 IF: 40.137 |
|
Call Number |
UA @ admin @ c:irua:171150 |
Serial |
6513 |
Permanent link to this record |
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Author |
Mei, B.; Wiktor, C.; Turner, S.; Pougin, A.; Van Tendeloo, G.; Fischer, R.A.; Muhler, M.; Strunk, J. |
|
Title |
Evidence for metalsupport interactions in Au modified TiOx/SBA-15 materials prepared by photodeposition |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
|
Volume |
3 |
Issue |
12 |
Pages |
3041-3049 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Gold nanoparticles have been efficiently photodeposited onto titanate-loaded SBA-15 (Ti(x)/SBA-15) with different titania coordination. Transmission electron microscopy shows that relatively large Au nanoparticles are photodeposited on the outer surface of the Ti(x)/SBA-15 materials and that TiOx tends to form agglomerates in close proximity to the Au nanoparticles, often forming coreshell Au/TiOx structures. This behavior resembles typical processes observed due to strong-metal support interactions. In the presence of gold, the formation of hydrogen on Ti(x)/SBA-15 during the photodeposition process and the performance in the hydroxylation of terephthalic acid is greatly enhanced. The activity of the Au/Ti(x)/SBA-15 materials is found to depend on the TiOx loading, increasing with a larger amount of initially isolated TiO4 tetrahedra. Samples with initially clustered TiOx species show lower photocatalytic activities. When isolated zinc oxide (ZnOx) species are present on Ti(x)/SBA-15, gold nanoparticles are smaller and well dispersed within the pores. Agglomeration of TiOx species and the formation of Au/TiOx structures is negligible. The dispersion of gold and the formation of Au/TiOx in the SBA-15 matrix seem to depend on the mobility of the TiOx species. The mobility is determined by the initial degree of agglomeration of TiOx. Effective hydrogen evolution requires Au/TiOx coreshell composites as in Au/Ti(x)/SBA-15, whereas hydroxylation of terephthalic acid can also be performed with Au/ZnOx/TiOx/SBA-15 materials. However, isolated TiOx species have to be grafted onto the support prior to the zinc oxide species, providing strong evidence for the necessity of TiOSi bridges for high photocatalytic activity in terephthalic acid hydroxylation. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000328231400044 |
Publication Date |
2013-11-05 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2155-5435;2155-5435; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
10.614 |
Times cited |
22 |
Open Access |
|
|
Notes |
262348 ESMI; FWO; 246791 COUNTATOMS; IAP-PAI; Hercules |
Approved |
Most recent IF: 10.614; 2013 IF: 7.572 |
|
Call Number |
UA @ lucian @ c:irua:112502 |
Serial |
1094 |
Permanent link to this record |
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Author |
Behera, B.C.; Jana, S.; Bhat, S.G.; Gauquelin, N.; Tripathy, G.; Kumar, P.S.A.; Samal, D. |
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Title |
Evidence for exchange bias coupling at the perovskite/brownmillerite interface in spontaneously stabilized SrCoO3-\delta/SrCoO2.5 bilayers |
Type |
A1 Journal article |
|
Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
Volume |
99 |
Issue |
2 |
Pages |
024425 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Interface effect in complex oxide thin-film heterostructures lies at the vanguard of current research to design technologically relevant functionality and explore emergent physical phenomena. While most of the previous works focus on the perovskite/perovskite heterostructures, the study of perovskite/brownmillerite interfaces remains in its infancy. Here, we investigate spontaneously stabilized perovskite-ferromagnet (SrCoO3-delta)/brownmillerite-antiferromagnet (SrCoO2.5) bilayer with T-N > T-C and discover an unconventional interfacial magnetic exchange bias effect. From magnetometry investigations, it is rationalized that the observed effect stems from the interfacial ferromagnet/antiferromagnet coupling. The possibility for coupled ferromagnet/spin-glass interface engendering such effect is ruled out. Strikingly, a finite coercive field persists in the paramagnetic state of SrCoO3-delta,whereas the exchange bias field vanishes at T-C . We conjecture the observed effect to be due to the effective external quenched staggered field provided by the antiferromagnetic layer for the ferromagnetic spins at the interface. Our results not only unveil a paradigm to tailor the interfacial magnetic properties in oxide heterostructures without altering the cations at the interface, but also provide a purview to delve into the fundamental aspects of exchange bias in such unusual systems, paving a big step forward in thin-film magnetism. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
|
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Language |
|
Wos |
000456481900003 |
Publication Date |
2019-01-23 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
OpenAccess |
|
Notes |
; We are grateful to Sachin Sarangi for his superb technical support during magnetic measurements. We thank Gopal Pradhan for fruitful discussion. We thank Zhicheng Zhong for reading the manuscript and for suggestions. We thank T. Som for extending laboratory facility. D.S. and B.C.B. acknowledge the financial support from Max-Planck Society through Max Planck Partner Group. S.G.B. acknowledges the INSPIRE Faculty Fellowship Programme (DSTO1899) for the financial support. ; |
Approved |
Most recent IF: 3.836 |
|
Call Number |
UA @ admin @ c:irua:157562 |
Serial |
5248 |
Permanent link to this record |
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|
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Author |
Mishra, R.S.K.; Pandey, D.; Lemmens, H.; Van Tendeloo, G. |
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Title |
Evidence for another low-temperature phase transition in tetragonal Pb(ZrxTi1-x)O3 (x=0.515,0.520) |
Type |
A1 Journal article |
|
Year |
2001 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
Volume |
64 |
Issue |
5 |
Pages |
054104 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Results of dielectric and resonance frequency (f(r)) measurements below room temperature are presented for Pb(ZrxTi1-x)O-3, x = 0.515 and 0.520. It is shown that the temperature coefficient of f(r) changes sign from negative to positive around 210 and 265 K for x = 0.520 and 200 and 260 K for x = 0.515. Anomalies in the real part of the dielectric constant (epsilon') are observed around the same temperatures at which the temperature coefficient of f(r) changes sign because of the electrostrictive coupling between the elastic and dielectric responses. Low-temperature powder x-ray-diffraction (XRD) data, however, reveal only one transition from the tetragonal to monoclinic phase similar to that reported by Noheda et al. [Phys. Rev. B, 61, 8687 (2000)]. Electron-diffraction data, on the other hand, reveal yet another structural transition at lower temperatures corresponding to the second anomaly in the epsilon' vs T and f(r) vs T curves. This second transition is shown to be a cell-doubling transition not observed by Noheda et al. in their XRD studies. The observation of superlattice reflections raises doubts about the correctness of the Cm space group proposed by Noheda et al. for the monoclinic phase of Pb(ZrxTi(1-x))O-3 below the second transition temperature. |
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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 |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000170267000028 |
Publication Date |
2002-07-27 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.836 |
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 3.836; 2001 IF: NA |
|
Call Number |
UA @ lucian @ c:irua:103407 |
Serial |
1093 |
Permanent link to this record |
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|
|
Author |
Pearce, P.E.; Perez, A.J.; Rousse, G.; Saubanère, M.; Batuk, D.; Foix, D.; McCalla, E.; Abakumov, A.M.; Van Tendeloo, G.; Doublet, M.-L.; Tarascon, J.-M. |
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Title |
Evidence for anionic redox activity in a tridimensional-ordered Li-rich positive electrode β-Li2IrO3 |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
|
Volume |
16 |
Issue |
5 |
Pages |
580-586 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Lithium-ion battery cathode materials have relied on cationic redox reactions until the recent discovery of anionic redox activity in Li-rich layered compounds which enables capacities as high as 300 mAh g(-1). In the quest for new high-capacity electrodes with anionic redox, a still unanswered question was remaining regarding the importance of the structural dimensionality. The present manuscript provides an answer. We herein report on a beta-Li2IrO3 phase which, in spite of having the Ir arranged in a tridimensional (3D) framework instead of the typical two-dimensional (2D) layers seen in other Li-rich oxides, can reversibly exchange 2.5 e(-) per Ir, the highest value ever reported for any insertion reaction involving d-metals. We show that such a large activity results from joint reversible cationic (Mn+) and anionic (O-2)(n-) redox processes, the latter being visualized via complementary transmission electron microscopy and neutron diffraction experiments, and confirmed by density functional theory calculations. Moreover, beta-Li2IrO3 presents a good cycling behaviour while showing neither cationic migration nor shearing of atomic layers as seen in 2D-layered Li-rich materials. Remarkably, the anionic redox process occurs jointly with the oxidation of Ir4+ at potentials as low as 3.4 V versus Li+/Li-0, as equivalently observed in the layered alpha-Li2IrO3 polymorph. Theoretical calculations elucidate the electrochemical similarities and differences of the 3D versus 2D polymorphs in terms of structural, electronic and mechanical descriptors. Our findings free the structural dimensionality constraint and broaden the possibilities in designing high-energy-density electrodes for the next generation of Li-ion batteries. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000400004200018 |
Publication Date |
2017-02-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
|
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1476-1122 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
39.737 |
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
The authors thank Q. Jacquet for fruitful discussions and V. Pomjakushin for his valuable help in neutron diffraction experiments. This work is based on experiments performed at the Swiss Spallation Neutron Source SINQ, Paul Scherrer Institute, Villigen, Switzerland. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the US Department of Energy under contract No. DE-AC02-06CH11357 and is greatly acknowledged. J.-M.T. acknowledges funding from the European Research Council (ERC) (FP/2014)/ERC Grant-Project 670116-ARPEMA. E.M. acknowledges financial support from the Fonds de Recherche du Quebec-Nature et Technologies. |
Approved |
Most recent IF: 39.737 |
|
Call Number |
EMAT @ emat @c:irua:147502 |
Serial |
4773 |
Permanent link to this record |
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Author |
Jannis, D.; Hofer, C.; Gao, C.; Xie, X.; Béché, A.; Pennycook, Tj.; Verbeeck, J. |
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Title |
Event driven 4D STEM acquisition with a Timepix3 detector: Microsecond dwell time and faster scans for high precision and low dose applications |
Type |
A1 Journal article |
|
Year |
2022 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
233 |
Issue |
|
Pages |
113423 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Four dimensional scanning transmission electron microscopy (4D STEM) records the scattering of electrons in a material in great detail. The benefits offered by 4D STEM are substantial, with the wealth of data it provides facilitating for instance high precision, high electron dose efficiency phase imaging via centre of mass or ptychography based analysis. However the requirement for a 2D image of the scattering to be recorded at each probe position has long placed a severe bottleneck on the speed at which 4D STEM can be performed. Recent advances in camera technology have greatly reduced this bottleneck, with the detection efficiency of direct electron detectors being especially well suited to the technique. However even the fastest frame driven pixelated detectors still significantly limit the scan speed which can be used in 4D STEM, making the resulting data susceptible to drift and hampering its use for low dose beam sensitive applications. Here we report the development of the use of an event driven Timepix3 direct electron camera that allows us to overcome this bottleneck and achieve 4D STEM dwell times down to 100 ns; orders of magnitude faster than what has been possible with frame based readout. We characterize the detector for different acceleration voltages and show that the method is especially well suited for low dose imaging and promises rich datasets without compromising dwell time when compared to conventional STEM imaging. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000734396800003 |
Publication Date |
2021-11-13 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.2 |
Times cited |
31 |
Open Access |
OpenAccess |
|
Notes |
This project has received funding from the Euro- pean Union’s Horizon 2020 Research Infrastructure – Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3. J.V. and A.B. acknowledge funding from FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’). J.V. and D.J. ac- knowledge funding from FWO project G042920N ‘Co- incident event detection for advanced spectroscopy in transmission electron microscopy’. We acknowledge funding under the European Union’s Horizon 2020 re- search and innovation programme (J.V. and D.J un- der grant agreement No 101017720, FET-Proactive EBEAM, and C.H., C.G., X.X. and T.J.P. from the Eu- ropean Research Council (ERC) Grant agreement No. 802123-HDEM).; esteem3JRA; esteem3reported |
Approved |
Most recent IF: 2.2 |
|
Call Number |
EMAT @ emat @c:irua:183948 |
Serial |
6828 |
Permanent link to this record |
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Author |
Montoya, E.; Bals, S.; Rossell, M.D.; Schryvers, D.; Van Tendeloo, G. |
|
Title |
Evaluation of top, angle, and side cleaned FIB samples for TEM analysis |
Type |
A1 Journal article |
|
Year |
2007 |
Publication |
Microscopy research and technique |
Abbreviated Journal |
Microsc Res Techniq |
|
Volume |
70 |
Issue |
12 |
Pages |
1060-1071 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
ITEM specimens of a LaAlO3/SrTiO3 multilayer are prepared by FIB with internal lift out. Using a Ga+1 beam of 5 kV, a final cleaning step yielding top, top-angle, side, and bottom-angle cleaning is performed. Different cleaning procedures, which can be easily implemented in a dual beam FIB system, are described and compared; all cleaning types produce thin lamellae, useful for HRTEM and HAADF-STEM work up to atomic resolution. However, the top cleaned lamellae are strongly affected by the curtain effect. Top-angle cleaned specimens show an amorphous layer of around 5 nm at the specimen surfaces, due to damage and redeposition. Furthermore, it is observed that the LaAlO3 layers are preferentially destroyed and transformed into amorphous material, during the thinning process. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000251868200008 |
Publication Date |
2007-08-25 |
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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 |
|
Series Issue |
|
Edition |
|
|
ISSN |
1059-910X;1097-0029; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
1.147 |
Times cited |
36 |
Open Access |
|
|
Notes |
Aip; Fwo |
Approved |
Most recent IF: 1.147; 2007 IF: 1.644 |
|
Call Number |
UA @ lucian @ c:irua:67282 |
Serial |
1090 |
Permanent link to this record |
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Author |
Eleftheriadis, G.K.; Filippousi, M.; Tsachouridou, V.; Darda, M.-A.; Sygellou, L.; Kontopoulou, I.; Bouropoulos, N.; Steriotis, T.; Charalambopoulou, G.; Vizirianakis, I.S.; Van Tendeloo, G.; Fatouros, D.G. |
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Title |
Evaluation of mesoporous carbon aerogels as carriers of the non-steroidal anti-inflammatory drug ibuprofen |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
International journal of pharmaceutics |
Abbreviated Journal |
Int J Pharmaceut |
|
Volume |
515 |
Issue |
515 |
Pages |
262-270 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; Electron microscopy for materials research (EMAT) |
|
Abstract |
Towards the development of novel drug carriers for oral delivery of poorly soluble drugs mesoporous aerogel carbons (CAs), namely CA10 and CA20 with different pore sizes (10 and 20 nm, respectively), were evaluated. The non-steroidal anti-inflammatory lipophilic compound ibuprofen was incorporated via passive loading. The drug loaded carbon aerogels were systemically investigated by means of High-Resolution Transmission Electron Microscopy (HR-TEM), Nitrogen physisorption studies, X-ray diffraction (XRD), Differential Scanning Calorimetry (DSC), X-ray photon electron spectroscopy (XPS) and zeta-potential studies. In vitro release studies were performed in simulated intestinal fluids reflecting both fasted (FaSSIF) and fed (FeSSIF) state conditions. Cytotoxicity studies were conducted with human intestinal cells (Caco-2). Drug was in an amorphous state in the pores of the carbon carrier as shown from the physicochemical characterization studies. The results showed marked differences in the release profiles for ibuprofen from the two aerogels in the media tested whereas in vitro toxicity profiles appear to be compatible with potential therapeutic applications at low concentrations. (C) 2016 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
|
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Language |
|
Wos |
000389150700024 |
Publication Date |
2016-10-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0378-5173 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.649 |
Times cited |
7 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 3.649 |
|
Call Number |
UA @ lucian @ c:irua:140231 |
Serial |
4441 |
Permanent link to this record |
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Author |
Velazco, A.; Nord, M.; Béché, A.; Verbeeck, J. |
|
Title |
Evaluation of different rectangular scan strategies for STEM imaging |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
|
Issue |
|
Pages |
113021 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
STEM imaging is typically performed by raster scanning a focused electron probe over a sample. Here we investigate and compare three different scan patterns, making use of a programmable scan engine that allows to arbitrarily set the sequence of probe positions that are consecutively visited on the sample. We compare the typical raster scan with a so-called ‘snake’ pattern where the scan direction is reversed after each row and a novel Hilbert scan pattern that changes scan direction rapidly and provides an homogeneous treatment of both scan directions. We experimentally evaluate the imaging performance on a single crystal test sample by varying dwell time and evaluating behaviour with respect to sample drift. We demonstrate the ability of the Hilbert scan pattern to more faithfully represent the high frequency content of the image in the presence of sample drift. It is also shown that Hilbert scanning provides reduced bias when measuring lattice parameters from the obtained scanned images while maintaining similar precision in both scan directions which is especially important when e.g. performing strain analysis. Compared to raster scanning with flyback correction, both snake and Hilbert scanning benefit from dose reduction as only small probe movement steps occur. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
|
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Language |
|
Wos |
000544042800007 |
Publication Date |
2020-05-21 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.2 |
Times cited |
13 |
Open Access |
OpenAccess |
|
Notes |
A.V., A.B. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. M.N. received support for this work from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 838001. J.V acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. |
Approved |
Most recent IF: 2.2; 2020 IF: 2.843 |
|
Call Number |
EMAT @ emat @c:irua:169225 |
Serial |
6369 |
Permanent link to this record |
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|
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Author |
Kolchina, L. M.; Lyskov, N.V.; Kuznetsov, A.N.; Kazakov, S.M.; Galin, M.Z.; Meledin, A.; Abakumov, A.M.; Bredikhin, S.I.; Mazo, G.N.; Antipov, E.V. |
|
Title |
Evaluation of Ce-doped Pr2CuO4for potential application as a cathode material for solid oxide fuel cells |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
Volume |
6 |
Issue |
6 |
Pages |
101029-101037 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Pr2−xCexCuO4 (x = 0.05; 0.1; 0.15) samples were synthesized and systematically characterized towards application as a cathode material for solid oxide fuel cells (SOFCs). High-temperature electrical conductivity, thermal expansion, and electrocatalytic activity in the oxygen reduction reaction (ORR) were examined. The electrical conductivity of Pr2−xCexCuO4 oxides demonstrates semiconducting behavior up to 900 °C. Small Ce-doping (2.5 at%) allows an increase in electrical conductivity from 100 to 130 S cm−1 in air at 500–800 °C. DFT calculations revealed that the density of states directly below the Fermi level, comprised mainly of Cu 3d and O 2p states, is significantly affected by atoms in rare earth positions, which might give an indication of a correlation between calculated electronic structures and measured conducting properties. Ce-doping in Pr2−xCexCuO4 slightly increases TEC from 11.9 × 10−6 K−1 for x = 0 to 14.2 × 10−6 K−1 for x = 0.15. Substitution of 2.5% of Pr atoms in Pr2CuO4 by Ce is effective to enhance the electrochemical performance of the material as a SOFC cathode in the ORR (ASR of Pr1.95Ce0.05CuO4 electrode applied on Ce0.9Gd0.1O1.95 electrolyte is 0.39 Ω cm2 at 750 °C in air). The peak power density achieved for the electrolyte-supported fuel cell with the Pr1.95Ce0.05CuO4 cathode is 150 mW cm−2 at 800 °C |
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Address |
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Corporate Author |
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Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000387427700044 |
Publication Date |
2016-10-19 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2046-2069 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.108 |
Times cited |
7 |
Open Access |
|
|
Notes |
his work was partially supported by Russian Foundation for Basic Research (grant no. 153820247), Skolkovo Institute of Science and Technology (Center of electrochemical energy), and MSUdevelopment Program up to 2020. K.L.M. is grateful to Haldor Topsøe A/S for the financial support. |
Approved |
Most recent IF: 3.108 |
|
Call Number |
EMAT @ emat @ c:irua:136441 |
Serial |
4296 |
Permanent link to this record |
|
|
|
|
Author |
O'Donnell, D.; Hassan, S.; Du, Y.; Gauquelin, N.; Krishnan, D.; Verbeeck, J.; Fan, R.; Steadman, P.; Bencok, P.; Dobrynin, A.N. |
|
Title |
Etching induced formation of interfacial FeMn in IrMn/CoFe bilayers |
Type |
A1 Journal article |
|
Year |
2019 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
|
Volume |
52 |
Issue |
16 |
Pages |
165002 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
The effect of ion etching on exchange bias in IrMn3/Co70Fe30 bilayers is investigated. In spite of the reduction of saturation magnetization caused by the embedding of Tr from the capping layer into the Co70Fe30 layer during the etching process, the exchange bias in samples with the same thickness of the Co70Fe30 layer is reducing in proportion to the etching power. X-ray magnetic circular dichroism measurements revealed the emergence of an uncompensated Mn magnetization after etching, which is antiferromagnetically coupled to the ferromagnetic layer. This suggests etching induced formation of small interfacial FeMn regions which leads to the decrease of effective exchange coupling between ferromagnetic and antiferromagnetic layers. |
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Address |
|
|
Corporate Author |
|
Thesis |
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|
Publisher |
|
Place of Publication |
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Editor |
|
|
Language |
|
Wos |
000458524800001 |
Publication Date |
2019-01-31 |
|
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0022-3727 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
Impact Factor |
2.588 |
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
; This work was supported by Seagate Technology (Ireland). Beamline I10, Diamond Light Source, is acknowledged for provided beamtime. ; |
Approved |
Most recent IF: 2.588 |
|
Call Number |
UA @ admin @ c:irua:157458 |
Serial |
5247 |
Permanent link to this record |
|
|
|
|
Author |
den Dekker, A.J.; Gonnissen, J.; de Backer, A.; Sijbers, J.; Van Aert, S. |
|
Title |
Estimation of unknown structure parameters from high-resolution (S)TEM images : what are the limits? |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
134 |
Issue |
|
Pages |
34-43 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
Statistical parameter estimation theory is proposed as a quantitative method to measure unknown structure parameters from electron microscopy images. Images are then purely considered as data planes from which structure parameters have to be determined as accurately and precisely as possible using a parametric statistical model of the observations. For this purpose, an efficient algorithm is proposed for the estimation of atomic column positions and intensities from high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. Furthermore, the so-called CramérRao lower bound (CRLB) is reviewed to determine the limits to the precision with which continuous parameters such as atomic column positions and intensities can be estimated. Since this lower bound can only be derived for continuous parameters, alternative measures using the principles of detection theory are introduced for problems concerning the estimation of discrete parameters such as atomic numbers. An experimental case study is presented to show the practical use of these measures for the optimization of the experiment design if the purpose is to decide between the presence of specific atom types using STEM images. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
Language |
|
Wos |
000324474900006 |
Publication Date |
2013-06-01 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
31 |
Open Access |
|
|
Notes |
FWO; FP 2007-2013; Esteem2; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
|
Call Number |
UA @ lucian @ c:irua:109240 |
Serial |
1083 |
Permanent link to this record |
|
|
|
|
Author |
Chen, Q.; Skorikov, A.; van der Hoeven, J.E.S.; van Blaaderen, A.; Albrecht, W.; Perez-Garza, H.H.; Bals, S. |
|
Title |
Estimation of temperature homogeneity in MEMS-based heating nanochips via quantitative HAADF-STEM tomography |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Particle and particle systems characterization |
Abbreviated Journal |
|
|
Volume |
41 |
Issue |
2 |
Pages |
1-8 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Sample holders for transmission electron microscopy (TEM) based on micro-electro-mechanical systems (MEMS) have recently become popular for investigating the behavior of nanomaterials under in situ or environmental conditions. The accuracy and reproducibility of these in situ holders are essential to ensure the reliability of experimental results. In addition, the uniformity of an applied temperature trigger across the MEMS chip is a crucial parameter. In this work, it is measured the temperature homogeneity of MEMS-based heating sample supports by locally analyzing the dynamics of heat-induced alloying of Au@Ag nanoparticles located in different regions of the support through quantitative fast high-angle annular dark-field scanning TEM tomography. These results demonstrate the superior temperature homogeneity of a microheater design based on a heating element shaped as a circular spiral with a width decreasing outwards compared to a double spiral-shaped designed microheater. The proposed approach to measure the local temperature homogeneity based on the thermal properties of bimetallic nanoparticles will support the future development of MEMS-based heating supports with improved thermal properties and in situ studies where high precision in the temperature at a certain position is required. This schematic delineates an approach to quantifying potential localized temperature deviation within a nanochip. Employing two comparable nanoparticles as thermal probes in discrete nanochip regions, the alloying kinetics of these nanoparticles are monitorable using in situ quantitative high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) tomography, thus enabling the precise estimation of local temperature deviations.image |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
001060394600001 |
Publication Date |
2023-09-08 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0934-0866 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
Impact Factor |
2.7 |
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
This project was funded from the European Commission and The Marie Sklodowska-Curie Innovative Training Network MUMMERING (Grant Agreement no. 765604) |
Approved |
Most recent IF: 2.7; 2023 IF: 4.474 |
|
Call Number |
UA @ admin @ c:irua:199219 |
Serial |
8863 |
Permanent link to this record |
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|
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Author |
Dixit, H.; Tandon, N.; Cottenier, S.; Saniz, R.; Lamoen, D.; Partoens, B. |
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Title |
Erratum : First-principles study of possible shallow donors in ZnAl2O4 spinel [Phys. Rev. B 87, 174101 (2013)] |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
Volume |
88 |
Issue |
5 |
Pages |
059905-2 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000323572600009 |
Publication Date |
2013-08-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.836 |
Times cited |
1 |
Open Access |
|
|
Notes |
; ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
|
Call Number |
UA @ lucian @ c:irua:110015 |
Serial |
1080 |
Permanent link to this record |
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|
|
|
Author |
Leys, F.E.; March, N.H.; Lamoen, D.; van Doren, V.E. |
|
Title |
Equations of state of tantalum and plutonium in a spherical cell approximation and at extremely high pressures |
Type |
A1 Journal article |
|
Year |
2002 |
Publication |
|
Abbreviated Journal |
|
|
Volume |
22 |
Issue |
|
Pages |
217 |
|
Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
|
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
|
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: NA |
|
Call Number |
UA @ lucian @ c:irua:41408 |
Serial |
1077 |
Permanent link to this record |
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Author |
Fredrickx, P.; de Ryck, I.; Janssens, K.; Schryvers, D.; Petit, J.-P.; Döcking, H. |
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Title |
EPMA and µ-SRXRF analysis and TEM-based microstructure characterization of a set of Roman glass fragments |
Type |
A1 Journal article |
|
Year |
2004 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
X-Ray Spectrom |
|
Volume |
33 |
Issue |
5 |
Pages |
326-333 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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Address |
|
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
|
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Language |
|
Wos |
000223880800002 |
Publication Date |
2004-04-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0049-8246;1097-4539; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
1.298 |
Times cited |
13 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 1.298; 2004 IF: 1.391 |
|
Call Number |
UA @ lucian @ c:irua:48786 |
Serial |
1076 |
Permanent link to this record |
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Author |
Shen, Y.; Turner, S.; Yang, P.; Van Tendeloo, G.; Lebedev, O.I.; Wu, T. |
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Title |
Epitaxy-enabled vapor-liquid-solid growth of tin-doped indium oxide nanowires with controlled orientations |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
|
Volume |
14 |
Issue |
8 |
Pages |
4342-4351 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Controlling the morphology of nanowires in bottom-up synthesis and assembling them on planar substrates is of tremendous importance for device applications in electronics, photonics, sensing and energy conversion. To date, however, there remain challenges in reliably achieving these goals of orientation-controlled nanowire synthesis and assembly. Here we report that growth of planar, vertical and randomly oriented tin-doped indium oxide (ITO) nanowires can be realized on yttria-stabilized zirconia (YSZ) substrates via the epitaxy-assisted vaporliquidsolid (VLS) mechanism, by simply regulating the growth conditions, in particular the growth temperature. This robust control on nanowire orientation is facilitated by the small lattice mismatch of 1.6% between ITO and YSZ. Further control of the orientation, symmetry and shape of the nanowires can be achieved by using YSZ substrates with (110) and (111), in addition to (100) surfaces. Based on these insights, we succeed in growing regular arrays of planar ITO nanowires from patterned catalyst nanoparticles. Overall, our discovery of unprecedented orientation control in ITO nanowires advances the general VLS synthesis, providing a robust epitaxy-based approach toward rational synthesis of nanowires. |
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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 |
Editor |
|
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Language |
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Wos |
000340446200022 |
Publication Date |
2014-06-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
12.712 |
Times cited |
33 |
Open Access |
|
|
Notes |
European Union Seventh Framework Programme under Grant 312483 – ESTEEM; FWOl; esteem2_ta |
Approved |
Most recent IF: 12.712; 2014 IF: 13.592 |
|
Call Number |
UA @ lucian @ c:irua:118622 |
Serial |
1075 |
Permanent link to this record |
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|
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Author |
Chen, H.; Xiong, Y.; Li, J.; Abed, J.; Wang, D.; Pedrazo-Tardajos, A.; Cao, Y.; Zhang, Y.; Wang, Y.; Shakouri, M.; Xiao, Q.; Hu, Y.; Bals, S.; Sargent, E.H.H.; Su, C.-Y.; Yang, Z. |
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Title |
Epitaxially grown silicon-based single-atom catalyst for visible-light-driven syngas production |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
|
Volume |
14 |
Issue |
1 |
Pages |
1719-11 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Despite the natural abundance and promising properties of Si, there are few examples of crystalline Si-based catalysts. Here, the authors report an epitaxial growth method to construct Co single atoms on Si for light driven CO2 reduction to syngas. Improving the dispersion of active sites simultaneous with the efficient harvest of photons is a key priority for photocatalysis. Crystalline silicon is abundant on Earth and has a suitable bandgap. However, silicon-based photocatalysts combined with metal elements has proved challenging due to silicon's rigid crystal structure and high formation energy. Here we report a solid-state chemistry that produces crystalline silicon with well-dispersed Co atoms. Isolated Co sites in silicon are obtained through the in-situ formation of CoSi2 intermediate nanodomains that function as seeds, leading to the production of Co-incorporating silicon nanocrystals at the CoSi2/Si epitaxial interface. As a result, cobalt-on-silicon single-atom catalysts achieve an external quantum efficiency of 10% for CO2-to-syngas conversion, with CO and H-2 yields of 4.7 mol g((Co))(-1) and 4.4 mol g((Co))(-1), respectively. Moreover, the H-2/CO ratio is tunable between 0.8 and 2. This photocatalyst also achieves a corresponding turnover number of 2 x 10(4) for visible-light-driven CO2 reduction over 6 h, which is over ten times higher than previously reported single-atom photocatalysts. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000962607600018 |
Publication Date |
2023-03-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
16.6 |
Times cited |
6 |
Open Access |
OpenAccess |
|
Notes |
This work was supported by the National Natural Science Foundation of China (21821003, 21890380, 21905316), Guangdong Natural Science Foundation (2019A1515011748), the Science and Technology Planning Project of Guangdong Province (2019A050510018), Pearl River Recruitment Program of Talent (2019QN01C108), the EU Infrastructure Project EUSMI (Grant No. E190700310), and Sun Yat-sen University. D.W. acknowledges an Individual Fellowship funded by the Marie-Sklodowska-Curie Actions (MSCA) in Horizon 2020 program (grant 894254 SuprAtom). S.B. and A.P.-T. acknowledge financial support from the European Commission under the Horizon 2020 Programme by grant no. 731019 (EUSMI) and ERC Consolidator grant no. 815128 (REALNANO). This project has received funding from the European Commission Grant (EUSMI E190700310). Synchrotron XAS data described in this paper was performed at the Canadian Light Source, a national research facility of the University of Saskatchewan, which is supported by the Canada Foundation for Innovation (CFI), the Natural Sciences and Engineering Research Council (NSERC), the National Research Council (NRC), the Canadian Institutes of Health Research (CIHR), the Government of Saskatchewan, and the University of Saskatchewan. |
Approved |
Most recent IF: 16.6; 2023 IF: 12.124 |
|
Call Number |
UA @ admin @ c:irua:196062 |
Serial |
7932 |
Permanent link to this record |
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Author |
Cayado, P.; De Keukeleere, K.; Garzón, A.; Perez-Mirabet, L.; Meledin, A.; De Roo, J.; Vallés, F.; Mundet, B.; Rijckaert, H.; Pollefeyt, G.; Coll, M.; Ricart, S.; Palau, A.; Gázquez, J.; Ros, J.; Van Tendeloo, G.; Van Driessche, I.; Puig, T.; Obradors, X. |
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Title |
Epitaxial YBa2Cu3O7−xnanocomposite thin films from colloidal solutions |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
|
Volume |
28 |
Issue |
28 |
Pages |
124007 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
A methodology of general validity to prepare epitaxial nanocomposite films based on the use of colloidal solutions containing different crystalline preformed oxide nanoparticles ( ex situ nanocomposites) is reported. The trifluoroacetate (TFA) metal–organic chemical solution deposition route is used with alcoholic solvents to grow epitaxial YBa 2 Cu 3 O 7 (YBCO) films. For this reason stabilizing oxide nanoparticles in polar solvents is a challenging goal. We have used scalable nanoparticle synthetic methodologies such as thermal and microwave-assisted solvothermal techniques to prepare CeO 2 and ZrO 2 nanoparticles. We show that stable and homogeneous colloidal solutions with these nanoparticles can be reached using benzyl alcohol, triethyleneglycol, nonanoic acid, trifluoroacetic acid or decanoic acid as protecting ligands, thereby allowing subsequent mixing with alcoholic TFA solutions. An elaborate YBCO film growth analysis of these nanocomposites allows the identification of the different relevant growth phenomena, e.g. nanoparticles pushing towards the film surface, nanoparticle reactivity, coarsening and nanoparticle accumulation at the substrate interface. Upon mitigation of these effects, YBCO nanocomposite films with high self-field critical currents ( J c ∼ 3–4 MA cm −2 at 77 K) were reached, indicating no current limitation effects associated with epitaxy perturbation, while smoothed magnetic field dependences of the critical currents at high magnetic fields and decreased effective anisotropic pinning behavior confirm the effectiveness of the novel developed approach to enhance vortex pinning. In conclusion, a novel low cost solution-derived route to high current nanocomposite superconducting films and coated conductors has been developed with very promising features. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000366288100009 |
Publication Date |
2015-11-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.878 |
Times cited |
32 |
Open Access |
|
|
Notes |
All authors acknowledge the EU (EU-FP7 NMP-LA-2012-280432 EUROTAPES project). ICMAB acknowledges MINECO (MAT2014-51778-C2-1-R) and Generalitat de Catalunya (2014SGR 753 and Xarmae). UGhent acknowledges the Special Research Fund (BOF), the Research Foundation Flanders (FWO) and the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT). TEM microscopy work was conducted in the Catalan Institute of Nanoscience and Nanotechnology (ICN2). The authors acknowledge the ICN2 Electron Microscopy Division for offering access to their instruments and expertise. Part of the STEM microscopy work was conducted in 'Laboratorio de Microscopias Avanzadas' at the Instituto de Nanociencia de Aragon—Universidad de Zaragoza. The authors acknowledge the LMA-INA for offering access to their instruments and expertise. JG and MC also acknowledge the Ramon y Cajal program (RYC-2012-11709 and RYC-2013-12448 respectively). |
Approved |
Most recent IF: 2.878; 2015 IF: 2.325 |
|
Call Number |
c:irua:129593 |
Serial |
3966 |
Permanent link to this record |