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Author |
Kalesaki, E.; Boneschanscher, M.P.; Geuchies, J.J.; Delerue, C.; Morais Smith, C.; Evers, W.H.; Allan, G.; Altantzis, T.; Bals, S.; Vanmaekelbergh, D. |
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Title |
Preparation and study of 2-D semiconductors with Dirac type bands due to the honeycomb nanogeometry |
Type |
P1 Proceeding |
| |
Year |
2014 |
Publication |
Proceedings of the Society of Photo-optical Instrumentation Engineers
T2 – Proceedings of SPIE |
Abbreviated Journal |
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Volume  |
8981 |
Issue |
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Pages |
898107-898107 |
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Keywords |
P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The interest in 2-dimensional systems with a honeycomb lattice and related Dirac-type electronic bands has exceeded the prototype graphene1. Currently, 2-dimensional atomic2,3 and nanoscale4-8 systems are extensively investigated in the search for materials with novel electronic properties that can be tailored by geometry. The immediate question that arises is how to fabricate 2-D semiconductors that have a honeycomb nanogeometry, and as a consequence of that, display a Dirac-type band structure? Here, we show that atomically coherent honeycomb superlattices of rocksalt (PbSe, PbTe) and zincblende (CdSe, CdTe) semiconductors can be obtained by nanocrystal self-assembly and facet-to-facet atomic bonding, and subsequent cation exchange. We present a extended structural analysis of atomically coherent 2-D honeycomb structures that were recently obtained with self-assembly and facet-to-facet bonding9. We show that this process may in principle lead to three different types of honeycomb structures, one with a graphene type-, and two others with a silicene-type structure. Using TEM, electron diffraction, STM and GISAXS it is convincingly shown that the structures are from the silicene-type. In the second part of this work, we describe the electronic structure of graphene-type and silicene type honeycomb semiconductors. We present the results of advanced electronic structure calculations using the sp3d5s* atomistic tight-binding method10. For simplicity, we focus on semiconductors with a simple and single conduction band for the native bulk semiconductor. When the 3-D geometry is changed into 2-D honeycomb, a conduction band structure transformation to two types of Dirac cones, one for S- and one for P-orbitals, is observed. The width of the bands depends on the honeycomb period and the coupling between the nanocrystals. Furthermore, there is a dispersionless P-orbital band, which also forms a landmark of the honeycomb structure. The effects of considerable intrinsic spin-orbit coupling are briefly considered. For heavy-element compounds such as CdTe, strong intrinsic spin-‐orbit coupling opens a non-trivial gap at the P-orbital Dirac point, leading to a quantum Spin Hall effect10-12. Our work shows that well known semiconductor crystals, known for centuries, can lead to systems with entirely new electronic properties, by the simple action of nanogeometry. It can be foreseen that such structures will play a key role in future opto-electronic applications, provided that they can be fabricated in a straightforward way. |
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Wos |
000336040600004 |
Publication Date |
2014-03-07 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
This work has been supported by funding of the French National Research Agency [ANR, (ANR-‐09-‐BLAN-‐0421-‐01)], NWO and the Dutch organization FOM [Programs “Control over Functional Nanoparticle Solids” (FNPS) and “Designing Dirac Carriers in Semiconductors” |
Approved |
Most recent IF: NA |
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Call Number |
c:irua:131912 |
Serial |
4039 |
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Author |
Milat, O.; Van Tendeloo, G.; Amelinckx, S. |
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Title |
Structural description of high Tc cuprate superconductors |
Type |
A1 Journal article |
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Year |
1996 |
Publication |
Spie |
Abbreviated Journal |
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Volume |
2697 |
Issue |
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Pages |
95-105 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Wos |
A1996BG12A00011 |
Publication Date |
2005-01-24 |
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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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Additional Links |
UA library record; WoS full 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 |
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Call Number |
UA @ lucian @ c:irua:16869 |
Serial |
3230 |
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Author |
Meilikhov, M.; Yusenko, K.; Esken, D.; Turner, S.; Van Tendeloo, G.; Fischer, R.A. |
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Title |
Metals@MOFs – loading MOFs with metal nanoparticles for hybrid functions |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
European journal of inorganic chemistry |
Abbreviated Journal |
Eur J Inorg Chem |
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Volume |
2010 |
Issue |
24 |
Pages |
3701-3714 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Metalorganic frameworks (MOFs) as well as porous coordination polymers (PCPs) are porous, organicinorganic hybrid solids with zeolite-like structures and properties. Due to their extraordinarily high surface area and well defined pore structure MOFs can be used for the stabilization of metal nanoparticles with adjustable size. The embedded metal nanoparticles are still accessible for other reagents due to the high porosity of the MOF systems. This fact makes metal@MOF systems especially interesting for heterogeneous catalysis, gas storage and chemical sensing. This review compiles the cases of metal nanoparticles supported by or embedded into MOFs reported so far and the main aspects and problems associated with these novel nanocomposite systems. The determination of the dispersion and the location of the particles at the MOF support, the control of the loading degree and its effect on the catalytic activity of the system are discussed as well as the partial degradation of the MOF structure upon particle formation. Examples of the introduction of stabilizing groups into the MOF network that direct the loading and can influence the size and shape of the embedded particles are still rare and point into the possible direction of future investigations. Finally, the formation of bimetallic nanoparticles, which are stabilized and supported by a MOF network, will also be reviewed. |
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Place of Publication |
Weinheim |
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Wos |
000281684300001 |
Publication Date |
2010-07-09 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-1948; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.444 |
Times cited |
366 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.444; 2010 IF: 2.910 |
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Call Number |
UA @ lucian @ c:irua:85495 |
Serial |
2014 |
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Author |
Guttmann, P.; Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Umek, P.; Arcon, D.; Ewels, C.P.; Rehbein, S.; Heim, S.; Schneider, G. |
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Title |
TXM-NEXAFS of TiO2-based nanostructures |
Type |
P1 Proceeding |
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Year |
2011 |
Publication |
AIP conference proceedings |
Abbreviated Journal |
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Volume |
1365 |
Issue |
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Pages |
437-440 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
In this work, electronic properties of individual TiOx-pristine nanoribbons (NR) prepared by hydrothermal treatment of anatase TiO(2) micro-particles were studied using the HZB transmission x-ray microscope (TXM) at the BESSY II undulator beamline U41-FSGM. NEXAFS is ideally suited to study TiO(2)-based materials because both the O K-edge and Ti L-edge features are very sensitive to the local bonding environment, providing diagnostic information about the crystal structures and oxidation states of various forms of titanium oxides and sub-oxides. TXM-NEXAFS combines full-field x-ray microscopy with spectroscopy, allowing the study of the electronic structure of individual nanostructures with spatial resolution better than 25 nm and a spectral resolution of up to E/Delta E = 10000. The typical image field in TXM-NEXAFS measurements is about 10 mu m. 10 mu m, which is large compared to the individual nanoparticle. Therefore, one image stack already contains statistically significant data. In addition, the directional electric field vector ((E) over bar) of the x-rays can be used as a “search tool” for the direction of chemical bonds of the atom selected by its absorption edge. |
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Corporate Author |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000298672400103 |
Publication Date |
2011-09-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:113071 |
Serial |
3789 |
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Author |
Ben Abdallah, M.A.; Bacchi, A.; Parisini, A.; Canossa, S.; Bergamonti, L.; Balestri, D.; Kamoun, S. |
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Title |
Crystal structure, vibrational, electrical, optical and DFT study of C₂H₁0N₂(IO₃)₂.HIO₃ |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of Molecular Structure |
Abbreviated Journal |
J Mol Struct |
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Volume |
1215 |
Issue |
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Pages |
128254-12 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The reinvestigation of the EDA-HIO3-H2O system using a different stoichiometric ratio gives rise to a new iodate salt C2H10N2(IO3)(2 center dot)HIO3 denoted as EBIMIA. In this study, we reported the structural properties of ethylenediammonium bis iodate mono iodic acid using X-ray powder and single crystal diffraction at room temperature. The Hirshfeld and the potential energy surface analysis reveal that I center dot center dot center dot O and N-H center dot center dot center dot O are the most noticeable interactions that took place inside the crystal and contribute to the cohesion and stability of the synthesized compound. The DSC measurement shows that this iodate salt undergoes two structural phase transitions, the first occurs at T = 290 K while the second occurs at T = 363 K. However, the dielectric analysis confirms only the second transition because it lies in the studied temperature domain 338-413K. Besides, the impedance data obey a circuit model consisting of a parallel combination of a bulk resistance and CPE. The frequency dispersion of the conductivity follows Jonscher's law and the charge carrier transport may be interpreted using the correlation barrier hopping mechanism (CBH). Finally, the electronic properties and the vibrational analysis of this novel iodate salt are studied using DFT and compared to the experimental data given by the FT-IR, Raman and UV-visible spectroscopies. (C) 2020 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Place of Publication |
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Wos |
000537221300012 |
Publication Date |
2020-04-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-2860 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.8 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
; The authors are grateful to Pr. Giovani Predieri, Pr. Pier Paolo Lottici, and Pr. Danilo Bersani, for their help with the vibrational measurement. Moreover, authors wish to thank, Pr. Salvatore Vantaggio and Dr. Silvio Scaravonati for their contribution in carrying out the impedance spectroscopy measurements. The authors acknowledge also the Analytical Chemistry, Cultural Heritage, Inorganic Chemistry and Crystallography Unit (SCVSA department, university of Parma, Italy) and the Tunisian Ministry of Higher Education and Scientific Research (LR11ES46) for their support. ; |
Approved |
Most recent IF: 3.8; 2020 IF: 1.753 |
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Call Number |
UA @ admin @ c:irua:170148 |
Serial |
6480 |
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Author |
Michielsen, B.; Verlackt, C.; van der Veken, B.J.; Herrebout, W.A. |
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Title |
C-H\cdots X (X = S, P) hydrogen bonding : the complexes of halothane with dimethyl sulfide and trimethylphosphine |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal Of Molecular Structure |
Abbreviated Journal |
J Mol Struct |
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Volume |
1023 |
Issue |
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Pages |
90-95 |
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Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
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Abstract |
The formation of CH⋯S and CH⋯P hydrogen bonded complexes of halothane, CHBrClCF3, with dimethyl sulfide(-d6) and trimethylphosphine(-d9) have been studied in solutions of liquid krypton using infrared and Raman spectroscopy. In the 1:1 complexes, the halothane CH stretching mode is found to be red-shifted by 43 cm−1 in the dimethyl sulfide complex, and by 63 cm−1 in the trimethylphosphine complex. The complexation enthalpies were derived and amount to −10.7(2) and −11.2(2) kJ mol−1 for the respective complexes. The experiments were supported by ab initio calculations and Monte Carlo simulations. The obtained data for the CH⋯S and CH⋯P hydrogen bonds is compared to that of corresponding CH⋯O and CH⋯N hydrogen bonds. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000308971900017 |
Publication Date |
2012-03-23 |
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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 |
0022-2860; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.753 |
Times cited |
21 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.753; 2012 IF: 1.404 |
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Call Number |
UA @ lucian @ c:irua:100917 |
Serial |
3519 |
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Author |
Schowalter, M.; Rosenauer, A.; Lamoen, D.; Kruse, P.; Gerthsen, D. |
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Title |
Ab initio computation of the mean inner Coulomb potential of technological important semiconductors |
Type |
A1 Journal article |
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Year |
2005 |
Publication |
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Abbreviated Journal |
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Volume |
1007 |
Issue |
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Pages |
233-236 |
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Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
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Abstract |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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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 |
0930-8989 |
ISBN |
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Additional Links |
UA library record; WoS full 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 |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:72915 |
Serial |
32 |
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Author |
Lebedev, O.I.; Van Tendeloo, G. |
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Title |
Crystalline and amorphous frameworks with giant pores: what information ca we expect from advanced TEM? |
Type |
P1 Proceeding |
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Year |
2008 |
Publication |
Electron microscopy and multiscale modeling: proceedings of the AIP conference proceedings |
Abbreviated Journal |
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Volume |
999 |
Issue |
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Pages |
245-256 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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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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Edition |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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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 |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:69153 |
Serial |
580 |
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Author |
De Backer, A.; van den Bos, K.H.W.; Van den Broek, W.; Sijbers, J.; Van Aert, S. |
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Title |
StatSTEM: An efficient program for accurate and precise model-based quantification of atomic resolution electron microscopy images |
Type |
P1 Proceeding |
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Year |
2017 |
Publication |
Journal of physics : conference series
T2 – Electron Microscopy and Analysis Group Conference 2017 (EMAG2017), 3-6 July 2017, Manchester, UK |
Abbreviated Journal |
J. Phys.: Conf. Ser. |
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Volume |
902 |
Issue |
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Pages |
012013 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
An efficient model-based estimation algorithm is introduced in order to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for the overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, is investigated. The highest attainable precision is reached even for low dose images. Furthermore, advantages of the model- based approach taking into account overlap between neighbouring columns are highlighted. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. |
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Wos |
000416370700013 |
Publication Date |
2017-10-16 |
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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 |
1742-6588 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
The authors acknowledge nancial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0374.13N, G.0368.15N, G.0369.15N, WO.010.16N) and a PhD research grant to K H W van den Bos, and a postdoctoral research grant to A De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3). A Rosenauer is acknowledged for providing the STEMsim program. |
Approved |
Most recent IF: NA |
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Call Number |
EMAT @ emat @c:irua:147188 |
Serial |
4764 |
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Author |
Safdel, A.; Zarei-Hanzaki, A.; Abedi, H.R.; Pourbabak, S.; Schryvers, D.; Basu, R. |
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Title |
Asymmetrical superelastic behavior of thermomechanically processed semi-equiatomic NiTi alloy in tensile and compressive modes of deformation |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
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Volume |
878 |
Issue |
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Pages |
160443 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In the present work two different cold working and annealing schemes were utilized, and the asymmetric superelastic response of thermomechanically processed materials were then assessed through cyclic tensile and compressive modes of deformation. The values of transformation stress, transformation strain, and pseudoelastic strain were measured for each treated and solutionized specimens and the asymmetric response was compared. In the solution annealed state, the difference of these parameters at different deformation modes was negligible due to the weak texture of the material, while for thermomechanically treated ones, development of specific deformation and recrystallization texture components was identified to be one of the underlying reasons of intensified asymmetry. The evolved substructure during the thermomechanical processing also played a substantial role in determining the asymmetric response. The presence of fine grains and dense dislocation substructure could hinder the movement of the transformation front, thus limiting the range of transformation. In tensile mode, the transformation stress was lower, but higher transformation strain was achieved, which was discussed relying on the slip activity in specified oriented grains. The lower transformation strain in compression mode led to lower pseudoelastic strain due to the narrow transformation range which finally degraded superelastic response of the material. (C) 2021 Elsevier B.V. All rights reserved. |
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Wos |
000660477400005 |
Publication Date |
2021-05-18 |
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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 |
0925-8388 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.133 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.133 |
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Call Number |
UA @ admin @ c:irua:179564 |
Serial |
6855 |
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Author |
Morsdorf, L.; Kashiwar, A.; Kübel, C.; Tasan, C.C. |
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Title |
Carbon segregation and cementite precipitation at grain boundaries in quenched and tempered lath martensite |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Materials science and engineering: part A: structural materials: properties, microstructure and processing |
Abbreviated Journal |
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Volume |
862 |
Issue |
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Pages |
144369-21 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Tempering is widely applied to make carbon atoms beneficially rearrange in high strength steel microstructures after quenching; though the nano-scale interaction of carbon atoms with crystallographic defects is hard to experimentally observe. To improve, we investigate the redistribution of carbon atoms along martensite grain boundaries in a quenched and tempered low carbon steel. We observe the tempering-induced microstructural evolution by in-situ heating in a transmission electron microscope (TEM) and by compositional analysis through atom probe tomography (APT). Probe volumes for APT originate from a single martensite packet but in different tempering conditions, which is achieved via a sequential lift-out with in-between tempering treatments. The complementary use of TEM and APT provides crystallographic as well as chemical information on carbon segregation and subsequent carbide precipitation at martensite grain boundaries. The results show that the amount of carbon segregation to martensite grain boundaries is influenced by the boundary type, e.g. low-angle lath or high-angle block boundaries. Also, the growth behavior of cementite precipitates from grain boundary nucleation sites into neighboring martensite grains differs at low- and high-angle grain boundaries. This is due to the crystallographic constraints arising from the semi-coherent orientation relationship between cementite and adjacent martensite. We also show that slower quenching stabilizes thin retained austenite films between martensite grains because of enhanced carbon segregation during cooling. Finally, we demonstrate the effect of carbon redistribution along martensite grain boundaries on the mechanical properties. Here, we compare micro-scale Vickers hardness results from boundary-containing probe volumes to nanoindentation results from pure bulk martensite (boundary-free) probe volumes. |
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Place of Publication |
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Wos |
000905165700001 |
Publication Date |
2022-12-07 |
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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 |
0921-5093 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
6.4 |
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 6.4; 2023 IF: 3.094 |
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| |
Call Number |
UA @ admin @ c:irua:192279 |
Serial |
7285 |
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| Permanent link to this record |
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Author |
Ding, L.; Zhao, L.; Weng, Y.; Schryvers, D.; Liu, Q.; Idrissi, H. |
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Title |
Atomic-scale investigation of the heterogeneous precipitation in the E (Al₁₈Mg₃Cr₂) dispersoid of 7075 aluminum alloy |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
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| |
Volume |
851 |
Issue |
|
Pages |
156890 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The heterogeneous precipitation of the eta (MgZn2) phase on the E (Al18Mg3Cr2) dispersoids of the 7075 aluminum alloy was systematically investigated by atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy dispersive X-ray spectrometry (EDX). It is found that coarse B particles are heterogeneously precipitated at the E particle interface after water quenching and isothermal aging at 120 degrees C. The incoherent E/Al interface is responsible for the high tendency of heterogeneous precipitation of the B phase. Two different orientation relationships (ORs) between the eta, E and Al matrix are identified: OR1 [2 (11) over bar0](eta)[011](E)//[(1) over bar 12](Al), (01 (1) over bar0)(eta)//(13 (3) over bar)(E)//(201)(Al), OR2 [(1) over bar 12](E)//[0001](eta)//[011](Al), (01 (1) over bar0 )(eta)//(220)(E)//(34 (4) over bar)(Al). The eta phase is preferential to nucleate along the {111}(E) or the {220}(E) planes, depending on its OR. The heterogeneous nucleation of B phase on the E particle could stabilize the E/Al interface by introducing a coherent E/eta interface, which increases the drive force of heterogeneous precipitation. The reorientation of eta phase and mutual diffusion of solute atoms could assist the coherency of the E/eta interface. The present results suggest that increasing the coherency of the E/Al interface is a promising method to suppress the heterogeneous precipitation of the eta phase. (C) 2020 Elsevier B.V. All rights reserved. |
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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 |
000579868900103 |
Publication Date |
2020-08-25 |
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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 |
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Series Issue |
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Edition |
|
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| |
ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.133 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.133 |
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Call Number |
UA @ admin @ c:irua:173503 |
Serial |
6717 |
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| Permanent link to this record |
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Author |
Chen, C.; Sang, X.; Cui, W.; Xing, L.; Nie, X.; Zhu, W.; Wei, P.; Hu, Z.-Y.; Zhang, Q.; Van Tendeloo, G.; Zhao, W. |
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Title |
Atomic-resolution fine structure and chemical reaction mechanism of Gd/YbAl₃ thermoelectric-magnetocaloric heterointerface |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
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| |
Volume |
831 |
Issue |
|
Pages |
154722-154728 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Thermoelectric materials and magnetocaloric materials are promising candidates for solid-state refrigeration applications. The combination of thermoelectric and magnetocaloric effects could potentially lead to more efficient refrigeration techniques. We designed and successfully synthesized Gd/YbAl3 composites using a YbAl3 matrix with good low-temperature thermoelectric performance and Gd microspheres with a high magnetocaloric performance, using a sintering condition of 750 degrees C and 50 MPa. Using aberration-corrected scanning transmission electron microscopy (STEM), it was discovered that the heterointerface between Gd and YbAl 3 is composed of five sequential interfacial layers: GdAl3, GdAl2, GdAl, Gd3Al2, and Gd3Al. The diffusion of Al atoms plays a crucial role in the formation of these interfacial layers, while Yb or Gd do not participate in the interlayer diffusion. This work provides the essential structural information for further optimizing and designing high-performance composites for thermoelectric-magnetocaloric hybrid refrigeration applications. (C) 2020 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000531727900005 |
Publication Date |
2020-03-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.2 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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| |
Notes |
; This work was supported by National Natural Science Foundation of China (Nos. 11834012, 51620105014, 91963207, 91963122, 51902237) and National Key R&D Program of China (No. 2018YFB0703603, 2019YFA0704903, SQ2018YFE010905). EPMA experiments were performed at the Center for Materials Research and Testing of Wuhan University of Technology. The S/TEM work was performed at the Nanostructure Research Center (NRC), which is supported by the Fundamental Research Funds for the Central Universities (WUT: 2019III012GX). ; |
Approved |
Most recent IF: 6.2; 2020 IF: 3.133 |
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Call Number |
UA @ admin @ c:irua:169447 |
Serial |
6455 |
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| Permanent link to this record |
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Author |
Ciocarlan, R.-G.; Seftel, E.M.; Gavrila, R.; Suchea, M.; Batuk, M.; Mertens, M.; Hadermann, J.; Cool, P. |
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Title |
Spinel nanoparticles on stick-like Freudenbergite nanocomposites as effective smart-removal photocatalysts for the degradation of organic pollutants under visible light |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
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| |
Volume |
820 |
Issue |
|
Pages |
153403 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
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Abstract |
A series of mixed nanocomposite materials was synthetized, containing a Ferrite phase type Zn1-xNixFe2O4 and a Freudenbergite phase type Na2Fe2Ti6O16, where x = 0; 0.2; 0.4; 0.6; 0.8; 1. The choice for this combination is based on the good adsorption properties of Freudenbergite for dye molecules, and the small bandgap energy of Ferrite spinel, allowing activation of the catalysts under visible light irradiation. A two steps synthesis protocol was used to obtain the smart-removal nanocomposites. Firstly, the spinel structure was obtained via the co-precipitation route followed by the addition of the Ti-source and formation of the Freudenbergite system. The role of cations on the formation mechanism and an interesting interchange of cations between spinel and Freudenbergite structures was clarified by a TEM study. Part of the Ti4+ penetrated the spinel structure and, at the same time, part of the Fe3+ formed the Freudenbergite system. The photocatalytic activity was studied under visible light, reaching for the best catalysts a 67% and 40% mineralization degree for methylene blue and rhodamine 6G respectively, after 6 h of irradiation. In the same conditions, the well-known commercial P25 (Degussa) managed to mineralize only 12% and 3% of methylene blue and rhodamine 6G, respectively. Due to the remarkable magnetic properties of Ferrites, a convenient recovery and reuse of the catalysts is possible after the photocatalytic tests. Based on the excellent catalytic performance of the nanocomposites under visible light and their ease of separation out of the solution after the catalytic reaction, the newly developed composite catalysts are considered very effective for wastewater treatment. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000507854700130 |
Publication Date |
2019-12-15 |
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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 |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.2 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
The authors acknowledge the FWO-Flanders (project nr. G038215N) for financial support. |
Approved |
Most recent IF: 6.2; 2020 IF: 3.133 |
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Call Number |
EMAT @ emat @c:irua:166447 |
Serial |
6342 |
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| Permanent link to this record |
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Author |
Li, J.; Zhao, C.; Yang, Y.; Li, C.; Hollenkamp, T.; Burke, N.; Hu, Z.-Y.; Van Tendeloo, G.; Chen, W. |
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Title |
Synthesis of monodispersed CoMoO4 nanoclusters on the ordered mesoporous carbons for environment-friendly supercapacitors |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Journal of alloys and compounds |
Abbreviated Journal |
J Alloy Compd |
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| |
Volume |
810 |
Issue |
810 |
Pages |
151841 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Binary metal oxides with superior charge capacity and electrochemical activity have gained great interests. In this work, monodispersed CoMoO4 nanoclusters on the ordered mesoporous carbons were fabricated by a facile self-developed impregnation method. The synthesized hybrids possess improved wettability, high specific surface area (> 700m(2)/g) and regular mesoporous channels (similar to 4 nm), resulting in improved electrochemical performance for supercapacitors. These well-dispersed CoMoO4 nanoclusters exhibit a significant specific capacitance up to 367 F/g in the aqueous KNO3 electrolyte and good reversibility with a cycling efficiency of 99.8%. It is proposed that the mesoporous structure can facilitate the diffusion of electrolyte ions and then accelerate the electrochemical utilization of CoMoO4 nanoclusters. The results demonstrate that the produced binary metal oxide nanoclusters with excellent capacitance and good retention can be used as promising electrodes for the environment-friendly supercapacitors. (C) 2019 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000486596000030 |
Publication Date |
2019-08-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.133 |
Times cited |
6 |
Open Access |
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Notes |
; Financial support by the National Key R&D Program of China (2016YB0303900) and the Fundamental Research Funds for the Central Universities (WUT: 2019III012GX) are gratefully acknowledged. The authors extend their appreciation to the support by CSIRO. ; |
Approved |
Most recent IF: 3.133 |
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Call Number |
UA @ admin @ c:irua:162759 |
Serial |
5398 |
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Author |
Germain, M.; Leys, M.; Boeykens, S.; Degroote, S.; Wang, W.; Schreurs, D.; Ruythooren, W.; Choi, K.-H.; van Daele, B.; Van Tendeloo, G.; Borghs, G. |
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Title |
High electron mobility in AlGaN/GaN HEMT grown on sapphire: strain modification by means of AIN interlayers |
Type |
P1 Proceeding |
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Year |
2004 |
Publication |
Materials Research Society symposium proceedings |
Abbreviated Journal |
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Volume |
798 |
Issue |
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Pages |
Y10.22,1-6 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
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Corporate Author |
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Publisher |
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Place of Publication |
Wuhan |
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 |
0272-9172 |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:54861 |
Serial |
1424 |
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| Permanent link to this record |
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Author |
Yang, M.; Chen, H.; Orekhov, A.; Lu, Q.; Lan, X.; Li, K.; Zhang, S.; Song, M.; Kong, Y.; Schryvers, D.; Du, Y. |
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Title |
Quantified contribution of β″ and β′ precipitates to the strengthening of an aged Al–Mg–Si alloy |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Materials Science And Engineering A-Structural Materials Properties Microstructure And Processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
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Volume |
774 |
Issue |
|
Pages |
138776 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
It is generally believed that β00 precipitates, rather than β0 precipitates, are the major strengthening precipitates in
aged Al–Mg–Si alloys. The reason for this difference is not well understood. To clarify this, two samples of the
same Al–Mg–Si alloy but with different aging states were prepared. The under-aged sample only contains nanoprecipitates
of the β00 type, while the peak-aged one contains nearly equal volumes of β00 and β0 precipitates. We
have, for the first time, separated the strengthening effect of the contribution from βʺ and βʹ precipitates,
respectively, by an indirect approach based on high-precision measurements of volume fractions, number densities,
sizes, proportions of the precipitates, their lattice strains, the composition and grain size of the matrix. The
β0 precipitates, which take 45.6% of the total precipitate volume in the peak-aged sample, contribute to the entire
precipitation strengthening by only 31.6%. The main reason why they are less useful compared to β00 precipitates
has been found to be associated with their smaller lattice strains relative to the matrix, which is 0.99% versus
2.10% (for β00 ). |
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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 |
000514747200001 |
Publication Date |
2019-12-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0921-5093 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.4 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
National Natural Science Foundation of China, 51531009 51711530713 51501230 ; Central South University, 2018gczd033 ; Flemish Science Foundation, VS.026.18N ; Program for Guangdong Introducing Innovative and Entrepreneurial Teams, 2016ZT06G025 ; Guangdong Natural Science Foundation, 2017B030306014 ; |
Approved |
Most recent IF: 6.4; 2020 IF: 3.094 |
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Call Number |
EMAT @ emat @c:irua:165290 |
Serial |
5440 |
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| Permanent link to this record |
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Author |
Samaee, V.; Sandfeld, S.; Idrissi, H.; Groten, J.; Pardoen, T.; Schwaiger, R.; Schryvers, D. |
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Title |
Dislocation structures and the role of grain boundaries in cyclically deformed Ni micropillars |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Materials Science And Engineering A-Structural Materials Properties Microstructure And Processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
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Volume |
769 |
Issue |
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Pages |
138295 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Transmission electron microscopy and finite element-based dislocation simulations were combined to study the development of dislocation microstructures after cyclic deformation of single crystal and bicrystal Ni micropillars oriented for multi-slip. A direct correlation between large accumulation of plastic strain and the presence of dislocation cell walls in the single crystal micropillars was observed, while the presence of the grain boundary hampered the formation of wall-like structures in agreement with a smaller accumulated plastic strain. Automated crystallographic orientation and nanostrain mapping using transmission electron microscopy revealed the presence of lattice heterogeneities associated to the cell walls including long range elastic strain fields. By combining the nanostrain mapping with an inverse modelling approach, information about dislocation density, line orientation and Burgers vector direction was derived, which is not accessible otherwise in such dense dislocation structures. Simulations showed that the image forces associated with the grain boundary in this specific bicrystal configuration have only a minor influence on dislocation behavior. Thus, the reduced occurrence of “mature” cell walls in the bicrystal can be attributed to the available volume, which is too small to accommodate cell structures. |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
000500373800018 |
Publication Date |
2019-08-21 |
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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 |
0921-5093 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
6.4 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
Financial support from the Flemish (FWO) and German Research Foundation (DFG) through the European M-ERA.NET project “FaSS” (Fatigue Simulation near Surfaces) under the grant numbers GA.014.13 N,SCHW855/5-1, and SA2292/2-1 is gratefully acknowledged. V.S. acknowledges the FWO research project G012012 N “Understanding nanocrystalline mechanical behaviour from structural investigations”. H.I. is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). S.S. acknowledges financial support from the European Research Council through the ERC Grant Agreement No. 759419 (MuDiLingo – A Multiscale Dislocation Language for Data- Driven Materials Science). |
Approved |
Most recent IF: 6.4; 2020 IF: 3.094 |
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Call Number |
EMAT @ emat @c:irua:163475 |
Serial |
5371 |
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| Permanent link to this record |
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Author |
Weng, Y.; Jia, Z.; Ding, L.; Muraishi, S.; Wu, X.; Liu, Q. |
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Title |
The multiple orientation relationships and morphology of beta phase in Al-Mg-Si-Cu alloy |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Journal of alloys and compounds |
Abbreviated Journal |
J Alloy Compd |
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Volume |
767 |
Issue |
767 |
Pages |
81-89 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The orientation relationships (ORs), segregation behavior and morphologies of beta precipitate in an over aged Al-Mg-Si-Cu alloy are systematically characterized by atomic resolution high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM). Six different ORs and two morphologies, i.e. rod-and lath-like are revealed for beta precipitates, and Cu segregation at the (beta/alpha-Al interface is observed in all these precipitates. The rod-like beta precipitate has multiple beta-angles ranging from 6.1 to 14.1 degrees and non-uniform Cu segregation at the (beta/alpha-Al interface, while the lath-like beta precipitate has a constant beta-angle of 0 degrees and a periodic Cu segregation. These different ORs are explained to be attributable to the rotation of QP lattice, a near-hexagonal network of Si columns formed within beta precipitates, which causes different lattice matching of beta with alpha-Al lattice. These findings provide new insights in controlling the precipitation hardening and mechanical properties of this type of alloys. (C) 2018 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000446316500011 |
Publication Date |
2018-07-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0925-8388 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.133 |
Times cited |
4 |
Open Access |
OpenAccess |
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Notes |
; This work was supported by the Fundamental Research Funds for the Central Universities of China (Grant No. 2018CDJDCL001910611 and No. 2017CDJQJ308822), the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (Grant No. 51421001) and the program of China Sponsorship Council (No. 201706050125). ; |
Approved |
Most recent IF: 3.133 |
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| |
Call Number |
UA @ lucian @ c:irua:154720 |
Serial |
5131 |
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| Permanent link to this record |
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Author |
Zhao, L.; Macias, J.G.S.; Ding, L.; Idrissi, H.; Simar, A. |
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Title |
Damage mechanisms in selective laser melted AlSi10Mg under as built and different post-treatment conditions |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Microstructure And Processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
|
| |
Volume |
764 |
Issue |
764 |
Pages |
138210 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Selective laser melting (SLM) manufactured AlSi10Mg alloys present a fine silicon-rich network and precipitates which grant high mechanical strength but low ductility. Post-treatments, aiming at eliminating inherent defects related to SLM such as residual stresses, porosity or inhomogeneity, result in significant changes in the microstructure and impact both the hardening and the damage mechanisms of the post-treated material. The present work is dedicated to the investigation of the fracture of SLM AlSi10Mg under as built and three post-treatment conditions, namely two stress relieve heat treatments and friction stir processing (FSP). It is found that the interconnected Si network fosters damage at low strain due to the brittleness of the Si phase. The onset of damage transfers load to the enclosed Al phase which then fractures quickly under high stress, thus leading to low material ductility. In contrast, when the Si network is globularized into Si particles, the ductility is highly increased even in the case where the porosity and inhomogeneity of the microstructure remain after the post-treatment. The ductility enhancement results from the delay in void nucleation on the Si particles as well as from the tolerance for void growth in the Al matrix. |
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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 |
000486360100029 |
Publication Date |
2019-07-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0921-5093 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.094 |
Times cited |
1 |
Open Access |
|
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| |
Notes |
; This research work has been supported by the WALInnov LongLifeAM project, Convention n 1810016, funded by Service public de Wallonie Economic Emploi Recherche (SPW-EER). L. Ding and A. Simar acknowledge the financial support of the European Research Council (ERC) for the Starting Grant ALUFIX project (grant agreement n 716678). J. G. Santos Macias acknowledges the support of the Fonds de la recherche scientifique -FNRS (FRIA grant), Belgium. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSRFNRS). Any-Shape is acknowledged for material supply. We thank Prof. P. J. Jacques from UCLouvain for fruitful discussion and critical reading of the paper. ; |
Approved |
Most recent IF: 3.094 |
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| |
Call Number |
UA @ admin @ c:irua:162800 |
Serial |
5386 |
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| Permanent link to this record |
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| |
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Author |
Jimenez-Mena, N.; Jacques, P.J.; Ding, L.; Gauquelin, N.; Schryvers, D.; Idrissi, H.; Delannay, F.; Simar, A. |
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| |
Title |
Enhancement of toughness of Al-to-steel Friction Melt Bonded welds via metallic interlayers |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Materials science and engineering: part A: structural materials: properties, microstructure and processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
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| |
Volume |
740-741 |
Issue |
|
Pages |
274-284 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The toughness of Al-to-steel welds decreases with increasing thickness of the intermetallic (IM) layer formed at the interface. Co plating has been added as interlayer in Al-to-steel Friction Melt Bonded (FMB) welds to control the nature and thickness of the IM layer. In comparison to a weld without interlayer, Co plating brings about a reduction of the thickness of the IM layer by 70%. The critical energy release rate of the crack propagating in the weld is used as an indicator of toughness. It is evaluated via an adapted crack propagation test using an energy conservation criterion. For a weld without interlayer, critical energy release rate is found to increase when the thickness of the intermetallic layer decreases. When the intermetallic layer is thick, the crack propagates in a brittle manner through the intermetallic whereas, at low layer thickness, the crack deviates and partially propagates through the Al plate, which causes an increase of toughness. The use of a Co interlayer brings about an increase of toughness by causing full deviation of the crack towards the Al plate. |
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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 |
000453494500029 |
Publication Date |
2018-10-24 |
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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 |
|
Edition |
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| |
ISSN |
0921-5093 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.094 |
Times cited |
4 |
Open Access |
Not_Open_Access: Available from 25.10.2020
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Notes |
The authors acknowledge the financial support of the Interuniversity Attraction Poles Program from the Belgian State through the Belgian Policy Agency, Belgium, contract IAP7/21 INTEMATE. N. Jimenez-Mena acknowledges the financial support of the (Fonds pour la formation à la recherchedans l'industrie et dans l'agriculture (FRIA), Belgium. A. Simar acknowledges the financial support of the (European Research Council – Starting Grant (ERC-StG), project ALUFIX, grant agreement no 716678. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS), Belgium. The authors also acknowledge M. Coulombier for the help provided in the measurement of the friction coefficient, and T. Pardoen and F. Lani for the fruitful discussions. |
Approved |
Most recent IF: 3.094 |
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| |
Call Number |
EMAT @ emat @c:irua:154866UA @ admin @ c:irua:154866 |
Serial |
5061 |
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| Permanent link to this record |
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Author |
Wang, X.; Amin-Ahmadi, B.; Schryvers, D.; Verlinden, B.; Van Humbeeck, J. |
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| |
Title |
Effect of annealing on the transformation behavior and mechanical properties of two nanostructured Ti-50.8at.%Ni thin wires produced by different methods |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Materials science forum |
Abbreviated Journal |
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| |
Volume |
738/739 |
Issue |
|
Pages |
306-310 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
A Ti-50.8at.%Ni wire produced using a co-drawing method and a commercial Ti-50.8at.%Ni wire were annealed at different temperatures between 450°C and 700°C. Grains with diameter less than 100nm were revealed by transmission electron microscopy for both wires before annealing treatment. However, the microstructural heterogeneity of the co-drawn wire is more obvious than that of the commercial wire. Multi-stage martensitic transformation was observed in the co-drawn wire, compared with the one-stage A↔M transformation in the commercial wire after annealing at 600°C for 30min. The differences of total elongation, plateau strain and pseudoelastic recoverable strain between the commercial wire and the co-drawn wire were also observed. The differences of the transformation behavior and mechanical properties between the commercial wire and the co-drawn wire are attributed to the microstructural difference between these two wires. |
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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 |
Lausanne |
Editor |
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| |
Language |
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Wos |
000316089000055 |
Publication Date |
2013-03-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1662-9752; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
5 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:104691 |
Serial |
798 |
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| Permanent link to this record |
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Author |
Shi, H.; Frenzel, J.; Schryvers, D. |
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Title |
EM characterization of precipitates in as-cast and annealed Ni45.5Ti45.5Nb9 shape memory alloys |
Type |
P1 Proceeding |
| |
Year |
2013 |
Publication |
Materials science forum |
Abbreviated Journal |
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| |
Volume |
738/739 |
Issue |
|
Pages |
113-117 |
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| |
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Nb-rich precipitates in the matrix of as-cast and annealed Ni45.5Ti45.5Nb9 alloys are investigated by scanning and scanning transmission electron microscopy, including slice-and-view and geometric phase analysis (GPA). The Nb-rich bcc nano-precipitates in the as-cast alloy have a 10% lattice parameter difference with the B2 matrix and reveal compensating interface dislocations. The 3D reconstruction of the configuration of small Nb-rich precipitates in the annealed alloy reveals a wall-like distribution of precipitates, which may increase the thermal hysteresis of the 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 |
Lausanne |
Editor |
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Language |
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Wos |
000316089000020 |
Publication Date |
2013-03-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1662-9752; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
1 |
Open Access |
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| |
Notes |
Fwo |
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:104690 |
Serial |
1028 |
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| Permanent link to this record |
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Author |
Schryvers, D.; Shi, H.; Martinez, G.T.; Van Aert, S.; Frenzel, J.; Van Humbeeck, J. |
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Title |
Nano- and microcrystal investigations of precipitates, interfaces and strain fields in Ni-Ti-Nb by various TEM techniques |
Type |
P1 Proceeding |
| |
Year |
2013 |
Publication |
Materials science forum
T2 – 9th European Symposium on Martensitic Transformations (ESOMAT 2012), SEP 09-16, 2012, St Petersburg, RUSSIA |
Abbreviated Journal |
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| |
Volume |
738/739 |
Issue |
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Pages |
65-71 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
In the present contribution several advanced electron microscopy techniques are employed in order to describe chemical and structural features of the nano- and microstructure of a Ni45.5Ti45.5Nb9 alloy. A line-up of Nb-rich nano-precipitates is found in the Ni-Ti-rich austenite of as-cast material. Concentration changes of the matrix after annealing are correlated with changes in the transformation temperatures. The formation of rows and plates of larger Nb-rich precipitates and particles is described. The interaction of a twinned martensite plate with a Nb-rich nano-precipitate is discussed and the substitution of Nb atoms on the Ti-sublattice in the matrix is confirmed. |
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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 |
Lausanne |
Editor |
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Language |
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Wos |
000316089000011 |
Publication Date |
2013-03-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
1662-9752; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
2 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:104692 |
Serial |
2247 |
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| Permanent link to this record |
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Author |
Weng, Y.; Jia, Z.; Ding, L.; Muraishi, S.; Liu, Q. |
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Title |
Clustering behavior during natural aging and artificial aging in Al-Mg-Si alloys with different Ag and Cu addition |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Microstructure And Processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
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| |
Volume |
732 |
Issue |
732 |
Pages |
273-283 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The effect of Ag and Cu addition on clustering behavior of Al-Mg-Si alloys during natural aging (NA) and artificial aging (AA) was investigated by hardness measurement, tensile test and atom probe tomography analysis. The results show that both Ag and Cu atoms could enter clusters and GP-zones, change the Mg/Si ratio and increase their volume fractions. Compared with the Al base alloy, the clusters in the Ag/Cu-added alloys more easily transform to beta" phases for size and compositional similarity, and the strengthening ability of these particles is enhanced by the increased volume fraction and shear modulus. In NA condition, Cu is greater in improving the volume fraction of clusters than Ag and thus produces higher T4 temper hardness. In AA condition, in contrary, Ag is more effective in facilitating the formation and growth of particles than Cu due to the stronger Ag-Mg interaction and the high diffusivity of Ag atoms in Al matrix, leading to highest hardening response. Compared to the Cu-added alloy, the Ag-added alloy shows higher precipitation kinetics during AA treatment and maintains a lower T4 temper hardness. |
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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 |
Lausanne |
Editor |
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Language |
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Wos |
000441486100032 |
Publication Date |
2018-07-07 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0921-5093 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.094 |
Times cited |
11 |
Open Access |
OpenAccess |
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| |
Notes |
; This work was supported by the Special major R & D Projects for Key Technology Innovation of Key Industries in Chongqing (Grant no. cstc2017zdcy-zdzxX0006), the Fundamental Research Funds for the Central Universities of China (Grant no. 106112016CDJXZ338825 and 106112017CDJQJ308822) and the program of China Scholarships Council (No. 201706050125). ; |
Approved |
Most recent IF: 3.094 |
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| |
Call Number |
UA @ lucian @ c:irua:153107 |
Serial |
5083 |
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| Permanent link to this record |
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Author |
Vladimirova, S.A.; Rumyantseva, M.N.; Filatova, D.G.; Chizhov, A.S.; Khmelevsky, N.O.; Konstantinova, E.A.; Kozlovsky, V.F.; Marchevsky, A.V.; Karakulina, O.M.; Hadermann, J.; Gaskov, A.M. |
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Title |
Cobalt location in p -CoO x / n -SnO 2 nanocomposites: Correlation with gas sensor performances |
Type |
A1 Journal Article |
| |
Year |
2017 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
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| |
Volume |
721 |
Issue |
|
Pages |
249-260 |
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| |
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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| |
Abstract |
Nanocomposites CoOx/SnO2 based on tin oxide powders with different crystallinity have been prepared by wet chemical synthesis and characterized in detail by ICP-MS, XPS, EPR, XRD, HAADF-STEM imaging and EDX-STEM mapping. It was shown that cobalt is distributed differently between the bulk and surface of SnO2 nanocrystals, which depends on the crystallinity of the SnO2 matrix. The measurements of gas sensor properties have been carried out during exposure to CO (10 ppm), and H2S (2 ppm) in dry air. The decrease of sensor signal toward CO was attributed to high catalytic activity of Co3O4 leading to oxidation of carbon monoxide entirely on the surface of catalyst particles. The formation of a p-CoOx/n-SnO2 heterojunction results in high sensitivity of nanocomposites in H2S detection. The conductance significantly changed in the presence of H2S, which was attributed to the formation of metallic cobalt sulfide and removal of the p – n junction. |
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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 |
000405252400030 |
Publication Date |
2017-06-02 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.133 |
Times cited |
|
Open Access |
Not_Open_Access |
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| |
Notes |
This work was supported by ERA-Net.Plus grant N 096 FONSENS. EPR experiments were performed using the facilities of the Collective Use Center at the Moscow State University. |
Approved |
Most recent IF: 3.133 |
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| |
Call Number |
EMAT @ emat @ |
Serial |
4711 |
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| Permanent link to this record |
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Author |
Vladimirova, S.A.; Rumyantseva, M.N.; Filatova, D.G.; Chizhov, A.S.; Khmelevsky, N.O.; Konstantinova, E.A.; Kozlovsky, V.F.; Marchevsky, A.V.; Karakulina, O.M.; Hadermann, J.; Gaskov, A.M. |
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Title |
Cobalt location in p-CoOxIn-SnO2 nanocomposites : correlation with gas sensor performances |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Journal of alloys and compounds |
Abbreviated Journal |
J Alloy Compd |
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| |
Volume |
721 |
Issue |
|
Pages |
249-260 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Nanocomposites CoOx/SnO2 based on tin oxide powders with different crystallinity have been prepared by wet chemical synthesis and characterized in detail by ICP-MS, XPS, EPR, XRD, HAADF-STEM imaging and EDX-STEM mapping. It was shown that cobalt is distributed differently between the bulk and surface of SnO2 nanocrystals, which depends on the crystallinity of the SnO2 matrix. The measurements of gas sensor properties have been carried out during exposure to CO (10 ppm), and H2S (2 ppm) in dry air. The decrease of sensor signal toward CO was attributed to high catalytic activity of Co3O4 leading to oxidation of carbon monoxide entirely on the surface of catalyst particles. The formation of a p-CoOx/n-SnO2 heterojunction results in high sensitivity of nanocomposites in H2S detection. The conductance significantly changed in the presence of H2S, which was attributed to the formation of metallic cobalt sulfide and removal of the p – n junction. (C) 2017 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 |
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Wos |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
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ISSN |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; ; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.133 |
Times cited |
|
Open Access |
Not_Open_Access: Available from 10.10.2019
|
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| |
Notes |
; This work was supported by ERA-Net.Plus grant N 096 FON-SENS. EPR experiments were performed using the facilities of the Collective Use Center at the Moscow State University. ; |
Approved |
Most recent IF: 3.133 |
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| |
Call Number |
UA @ lucian @ c:irua:145142 |
Serial |
4714 |
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| Permanent link to this record |
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Author |
Lumbeeck, G.; Delvaux, A.; Idrissi, H.; Proost, J.; Schryvers, D. |
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Title |
Analysis of internal stress build-up during deposition of nanocrystalline Ni thin films using transmission electron microscopy |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
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| |
Volume |
707 |
Issue |
|
Pages |
138076 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Ni thin films sputter-deposited at room temperature with varying Ar pressures were investigated with automated crystal orientation mapping in a transmission electron microscope to uncover the mechanisms controlling the internal stress build-up recorded in-situ during deposition. Large grains were found to induce behaviour similar to a stress-free nucleation layer. The measurements of grain size in most of the Ni thin films are in agreement with the island coalescence model. Low internal stress was observed at low Ar pressure and was explained by the presence of large grains. Relaxation of high internal stress was also noticed at the highest Ar pressure, which was attributed to a decrease of Σ3 twin boundary density due to a low deposition rate. The results provide insightful information to better understand the relationship between structural boundaries and the evolution of internal stress upon deposition of thin films. |
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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 |
000539312200011 |
Publication Date |
2020-05-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
This work was supported by the Hercules Foundation [Grant No. AUHA13009], the Flemish Research Fund (FWO) [Grant No. G.0365.15N], and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. Thin film deposition has been realised as part of the WallonHY project, funded by the Public Service of Wallonia – Department of Energy and Sustainable Building. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). |
Approved |
Most recent IF: NA |
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| |
Call Number |
EMAT @ emat @c:irua:169708 |
Serial |
6370 |
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| Permanent link to this record |
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Author |
Batuk, D.; Batuk, M.; Morozov, V.A.; Meert, K.W.; Smet, P.F.; Poelman, D.; Abakumov, A.M.; Hadermann, J. |
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| |
Title |
Effect of cation vacancies on the crystal structure and luminescent properties of Ca(0.85-1.5x)Gd(x)Eu(0.1)_(0.05+0.5x)WO(4) (0<x<0.567) scheelite-based red phosphors |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Journal of alloys and compounds |
Abbreviated Journal |
J Alloy Compd |
|
| |
Volume |
706 |
Issue |
706 |
Pages |
358-369 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The Ca0.85-1.5xGdxEu0.1_0.05-0.5xWO4 (0 < x < 0.567) series of cation-deficient scheelites is investigated to unveil the influence of the cation vacancies on the crystal structure and luminescent properties. The concentration of the vacancies is varied by the heterovalent substitution of Gd3+ for Ca2+, keeping the concentration of the Eu3+ luminescent centers constant in all compounds of the series. The crystal structure of the materials is studied using a combination of transmission electron microscopy and synchrotron X-ray powder diffraction. At low vacancy concentration (x = 0.1, 0.2), cations and cation vacancies are randomly distributed in the structure, and the materials preserve the I41/a symmetry of the parent scheelite structure [x = 0.1: a = 5.25151(1) Å, c = 11.39479(2) Å; x = 0.2: a = 5.25042(1) Å, c = 11.41335(2) Å]. At higher concentration, the cation-vacancy ordering gives rise to incommensurately modulated structures. The x = 0.3 structure has a (3 + 2)D tetragonal symmetry [superspace group I41/a(a,b,0)00(-b,a,0)00, a = 5.24700(1) Å, c = 11.45514(3) Å, q1 = 0.51637(14)a* + 0.80761(13)b*, q2 = -0.80761a* + 0.51637b*]. At x = 0.4, the scheelite basic cell undergoes a monoclinic distortion with the formation of the (3 + 1)D structure [superspace group I2/b(a,b,0)00, a = 5.23757(1) Å, b = 5.25035(1) Å, c = 11.45750(2) Å, g = 90.5120(2) o, q = 0.54206(8)a* + 0.79330(8)b*]. In both structures, the antiphase Ca and (Gd,Eu) occupancy modulations indicate that the ordering between the A cations and vacancies also induces partial Ca/(Gd,Eu) cation ordering. Further increase of the Gd3þ content up to x = 0.567 leads to the formation of a monoclinic phase (space group C2/c) with the Eu2/3WO4-type structure. Despite the difference in the cation-vacancy ordering patterns, all materials in the series demonstrate very similar quantum efficiency and luminescence decay lifetimes. However, the difference in the local coordination environment of the A cation species noticeably affects the line width and the multiplet splitting of the 4f6-4f6 transitions. |
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000397997300045 |
Publication Date |
2017-02-16 |
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0925-8388 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.133 |
Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
This research was supported by FWO (Flanders Research Foundation, project G039211N). V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741).We are grateful to the ESRF for granting the beamtime at the ID22 beamline and to Andy Fitch for the support during the experiment. |
Approved |
Most recent IF: 3.133 |
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Call Number |
EMAT @ emat @ c:irua:142367 |
Serial |
4581 |
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Author |
Belik, A.A.; Morozov, V.A.; Deyneko, D.V.; Savon, A.E.; Baryshnikova, O.V.; Zhukovskaya, E.S.; Dorbakov, N.G.; Katsuya, Y.; Tanaka, M.; Stefanovich, S.Y.; Hadermann, J.; Lazoryak, B.I. |
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Title |
Antiferroelectric properties and site occupations ofR3+ cations in Ca8MgR(PO4)7 luminescent host materials |
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A1 Journal article |
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2017 |
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Journal of alloys and compounds |
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699 |
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928-937 |
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A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Ca8MgR(PO4)(7) = La, Pr, Nd, Sm-Lu, and Y) phosphates with a beta-Ca-3(PO4)(2) related structure were prepared by a standard solid-state method in air. Second-harmonic generation, differential scanning calorimetry, and dielectric measurements led to the conclusion that all Ca8MgR(PO4)(7) are centrosymmetric and go to another centrosymmetric phase in the course of a first-order antiferroelectric phase transition well above room temperature (RT). High-temperature electron diffraction showed that the symmetry changes from R (3) over barc to R (3) over barm during the phase transition. Structures of Ca8MgR(PO4)(7) at RT were refined by the Rietveld method in centrosymmetric space group R (3) over barc. Mg2+ cations occupy the M5 site; the occupancy of the M1 site by R3+ cations increases monotonically from 0.0389 for R = La to 0.1667 for R = Er-Lu, whereas the occupancy of the M3 site by R3+ cations decreases monotonically from 0.1278 for R = La to 0 for R = Er-Lu. In the case of R = Er-Lu, the M3 site is occupied only by Ca2+ cations. P1O(4) tetrahedra and cations at the M3 site are disordered in the R (3) over barc structure of Ca8MgEu(PO4)(7). Using synchrotron X-ray powder diffraction, we found that annealing conditions do not significantly affect the distribution of Ca2+ and Eu3+ cations between the structure positions of Ca8MgEu(PO4)(7). Luminescent properties of CasMgEu(PO4)(7) powder samples were investigated under near-ultraviolet (n-UV) light. Excitation spectra of CasMgEu(PO4)(7) show the strongest absorption at about 395 nm that matches with commercially available n-UV-emitting GaN-based LED chips. Emission spectra show an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+. (C) 2016 Elsevier B.V. All rights reserved. |
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000393727500129 |
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2016-12-24 |
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0925-8388 |
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UA library record; WoS full record; WoS citing articles |
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UA @ admin @ c:irua:152665 |
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7464 |
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