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Author |
Wang, L.; Li, Y.; Yang, X.-Y.; Zhang, B.-B.; Ninane, N.; Busscher, H.J.; Hu, Z.-Y.; Delneuville, C.; Jiang, N.; Xie, H.; Van Tendeloo, G.; Hasan, T.; Su, B.-L. |
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Title |
Single-cell yolk-shell nanoencapsulation for long-term viability with size-dependent permeability and molecular recognition |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
National Science Review |
Abbreviated Journal |
Natl Sci Rev |
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Volume |
8 |
Issue |
4 |
Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract  |
Like nanomaterials, bacteria have been unknowingly used for centuries. They hold significant economic potential for fuel and medicinal compound production. Their full exploitation, however, is impeded by low biological activity and stability in industrial reactors. Though cellular encapsulation addresses these limitations, cell survival is usually compromised due to shell-to-cell contacts and low permeability. Here, we report ordered packing of silica nanocolloids with organized, uniform and tunable nanoporosities for single cyanobacterium nanoencapsulation using protamine as an electrostatic template. A space between the capsule shell and the cell is created by controlled internalization of protamine, resulting in a highly ordered porous shell-void-cell structure formation. These unique yolk-shell nano structures provide long-term cell viability with superior photosynthetic activities and resistance in harsh environments. In addition, engineering the colloidal packing allows tunable shell-pore diameter for size-dependent permeability and introduction of new functionalities for specific molecular recognition. Our strategy could significantly enhance the activity and stability of cyanobacteria for various nanobiotechnological applications. |
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Wos |
000651827200002 |
Publication Date |
2020-05-07 |
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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 |
2095-5138 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.843 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 8.843 |
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Call Number |
UA @ admin @ c:irua:179085 |
Serial |
6885 |
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| Permanent link to this record |
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Author |
Hamelet, S.; Casas-Cabanas, M.; Dupont, L.; Davoisne, C.; Tarascon, J.M.; Masquelier, C. |
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Title |
Existence of superstructures due to large amounts of Fe vacancies in the LiFePO4-type framework |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
23 |
Issue |
1 |
Pages |
32-38 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LiFePO4 has been under intense scrutiny over the past decade because it stands as an attractive positive electrode material for the next generation of Li-ion batteries to power electric vehicles and hybrid electric vehicles, hence the importance of its thermal behavior. The reactivity of LiFePO4 with air at moderate temperatures is shown to be dependent on its particle size. For nanosized materials, a progressive displacement of Fe from the core structure leading to a composite made of nanosize Fe2O3 and highly defective, oxidized LixFeyPO4 compositions, among which the “ideal” formula LiFe2/3PO4. Herein we report, from both temperature-controlled X-ray diffraction and electronic diffraction microscopy, that these off-stoichiometry olivine-type compounds show a defect ordering resulting in the formation of a superstructure. Such a finding shows striking similarities with the temperature-driven oxidation of fayalite Fe2SiO4 (another olivine) to structurally defective laihunite, reported in the literature three decades ago. |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000285726900007 |
Publication Date |
2010-12-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
30 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
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Call Number |
UA @ lucian @ c:irua:105605 |
Serial |
1130 |
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| Permanent link to this record |
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Author |
Shestakov, M.V.; Tikhomirov, V.K.; Kirilenko, D.; Kuznetsov, A.S.; Chibotaru, L.F.; Baranov, A.N.; Van Tendeloo, G.; Moshchalkov, V.V. |
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Title |
Quantum cutting in Li (770 nm) and Yb (1000 nm) co-dopant emission bands by energy transfer from the ZnO nano-crystalline host |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Optics express |
Abbreviated Journal |
Opt Express |
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| |
Volume |
19 |
Issue |
17 |
Pages |
15955-15964 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Li-Yb co-doped nano-crystalline ZnO has been synthesized by a method of thermal growth from the salt mixtures. X-ray diffraction, transmission electron microscopy, atomic absorption spectroscopy and optical spectroscopy confirm the doping and indicate that the dopants may form Li-Li and Yb3+-Li based nanoclusters. When pumped into the conduction and exciton absorption bands of ZnO between 250 to 425 nm, broad emission bands of about 100 nm half-height-width are excited around 770 and 1000 nm, due to Li and Yb dopants, respectively. These emission bands are activated by energy transfer from the ZnO host mostly by quantum cutting processes, which generate pairs of quanta in Li (770 nm) and Yb (1000 nm) emission bands, respectively, out of one quantum absorbed by the ZnO host. These quantum cutting phenomena have great potential for application in the down-conversion layers coupled to the Si solar cells. |
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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 |
000293894900033 |
Publication Date |
2011-08-04 |
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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 |
1094-4087; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.307 |
Times cited |
19 |
Open Access |
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Notes |
FWO; Methusalem |
Approved |
Most recent IF: 3.307; 2011 IF: 3.587 |
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Call Number |
UA @ lucian @ c:irua:92428 |
Serial |
2776 |
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| Permanent link to this record |
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Author |
McCalla, E.; Sougrati, M.T.; Rousse, G.; Berg, E.J.; Abakumov, A.; Recham, N.; Ramesha, K.; Sathiya, M.; Dominko, R.; Van Tendeloo, G.; Novák, P.; Tarascon, J.M.; |
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Title |
Understanding the roles of anionic redox and oxygen release during electrochemical cycling of lithium-rich layered Li4FeSbO6 |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
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Volume |
137 |
Issue |
137 |
Pages |
4804-4814 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Li-rich oxides continue to be of immense interest as potential next generation Li-ion battery positive electrodes, and yet the role of oxygen during cycling is still poorly understood. Here, the complex electrochemical behavior of Li4FeSbO6 materials is studied thoroughly with a variety of methods. Herein, we show that oxygen release occurs at a distinct voltage plateau from the peroxo/superoxo formation making this material ideal for revealing new aspects of oxygen redox processes in Li-rich oxides. Moreover, we directly demonstrate the limited reversibility of the oxygenated species (O-2(n-); n = 1, 2, 3) for the first time. We also find that during charge to 4.2 V iron is oxidized from +3 to an unusual +4 state with the concomitant formation of oxygenated species. Upon further charge to 5.0 V, an oxygen release process associated with the reduction of iron +4 to +3 is present, indicative of the reductive coupling mechanism between oxygen and metals previously reported. Thus, in full state of charge, lithium removal is fully compensated by oxygen only, as the iron and antimony are both very close to their pristine states. Besides, this charging step results in complex phase transformations that are ultimately destructive to the crystallinity of the material. Such findings again demonstrate the vital importance of fully understanding the behavior of oxygen in such systems. The consequences of these new aspects of the electrochemical behavior of lithium-rich oxides are discussed in detail. |
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Corporate Author |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000353177100036 |
Publication Date |
2015-03-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0002-7863;1520-5126; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.858 |
Times cited |
86 |
Open Access |
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Notes |
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Approved |
Most recent IF: 13.858; 2015 IF: 12.113 |
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Call Number |
c:irua:126019 |
Serial |
3805 |
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Author |
Sun, M.; Rousse, G.; Abakumov, A.M.; Saubanere, M.; Doublet, M.-L.; Rodriguez-Carvajal, J.; Van Tendeloo, G.; Tarascon, J.-M. |
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Title |
Li2Cu2O(SO4)2: a possible electrode for sustainable Li-based batteries showing a 4.7 V redox activity vs Li+/Li0 |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
27 |
Issue |
27 |
Pages |
3077-3087 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Li-ion batteries rely on the use of insertion positive electrodes with performances scaling with the redox potential of the 31) metals accompanying Liuptake/removal. Although not commonly studied, the Cu2+/Cu3+ redox potential has been predicted from theoretical calculations to possibly offer a high operating voltage redox couple. We herein report the synthesis and crystal structure of a hitherto-unknown oxysulfate phase, Li2Cu2O(SO4)(2), which contains infinite edgesharing CuO4 chains and presents attractive electrochemical redox activity with respect to Li+/Li, namely amphoteric characteristics. Li2Cu2O(SO4)(2) shows redox activity at 4.7 V vs Li+/Li corresponding to the oxidation of Cu2+ to Cu3+ enlisting ligand holes and associated with the reversible uptake-removal of 0.3 Li. Upon reduction, this compound reversibly uptakes similar to 2 Li at an average potential of about 2.5 V vs Li+/Li, associated with the Cu2+/Cu+ redox couple. The mechanism of the reactivity upon reduction is discussed in detail, with particular attention to the occasional appearance of an oscillation wave in the discharge profile. Our work demonstrates that Cu-based compounds can indeed be fertile scientific ground in the search for new high-energy-density electrodes. |
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Corporate Author |
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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 |
000353865800043 |
Publication Date |
2015-03-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
20 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466; 2015 IF: 8.354 |
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Call Number |
c:irua:126061 |
Serial |
3541 |
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Author |
Mushtaq, A.; Pradhan, B.; Kushavah, D.; Zhang, Y.; Wolf, M.; Schrenker, N.; Fron, E.; Bals, S.; Hofkens, J.; Debroye, E.; Pal, S.K. |
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Title |
Third-Order Nonlinear Optical Properties and Saturation of Two-Photon Absorption in Lead-Free Double Perovskite Nanocrystals under Femtosecond Excitation |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Acs Photonics |
Abbreviated Journal |
Acs Photonics |
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Volume |
8 |
Issue |
11 |
Pages |
3365-3374 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Lead halide perovskites have been widely explored
in the field of photovoltaics, light-emitting diodes, and lasers due to
their outstanding linear and nonlinear optical (NLO) properties.
But, the presence of lead toxicity and low chemical stability remain
serious concerns. Lead-free double perovskite with excellent
optical properties and chemical stability could be an alternative.
However, proper examination of the NLO properties of such a
material is crucial to identify their utility for future nonlinear device
applications. Herein, we have made use of femtosecond (fs) Z-scan
technique to explore the NLO properties of Cs2AgIn0.9Bi0.1Cl6
nanocrystals (NCs). Our measurements suggest that under
nonresonant fs excitation, perovskite NCs exhibit strong twophoton
absorption (TPA). The observed saturation of TPA at high
light intensities has been explained by a customized model. Furthermore, we have demonstrated a change in the nonlinear refractive
index of the NCs under varying input intensities. The strong TPA absorption of lead-free double perovskite NCs could be used for
Kerr nonlinearity-based nonlinear applications such as optical shutters for picosecond lasers. |
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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 |
000757024100028 |
Publication Date |
2021-11-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2330-4022 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.756 |
Times cited |
25 |
Open Access |
OpenAccess |
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Notes |
A.M. is thankful to IIT Mandi for his fellowship and Advanced Materials Research Centre for the experimental facilities. A.M. is also thankful to Torbjörn Pascher (Pascher Instrument) for writing the Z-scan data acquisition program. J.H. acknowledges financial support from the Research Foundation-Flanders (FWO, Grant No. G983.19N, G0A5817N, and G0H6316N) and the Flemish government through long-term structural funding Methusalem (CASAS2, Meth/15/04). B.P. acknowledges postdoctoral fellowship from the Research Foundation- Flanders (FWO Grant No. 1275521N). D.K. acknowledges the financial support from Science and Engineering Research Board (Grant No. PDF/2018/003146), India. N.J.S. acknowledges financial support from the Research Foundation- Flanders via a postdoctoral fellowship (FWO Grant No. 1238622N). |
Approved |
Most recent IF: 6.756 |
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Call Number |
EMAT @ emat @c:irua:184249 |
Serial |
6832 |
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Author |
Bhatia, H.; Martin, C.; Keshavarz, M.; Dovgaliuk, I.; Schrenker, N.J.; Ottesen, M.; Qiu, W.; Fron, E.; Bremholm, M.; Van de Vondel, J.; Bals, S.; Roeffaers, M.B.J.; Hofkens, J.; Debroye, E. |
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Title |
Deciphering the role of water in promoting the optoelectronic performance of surface-engineered lead halide perovskite nanocrystals |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
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Volume |
15 |
Issue |
5 |
Pages |
7294-7307 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Lead halide perovskites are promising candidates for applicability is limited by their structural instability toward moisture. Although a deliberate addition of water to the precursor solution has recently been shown to improve the crystallinity and optical properties of perovskites, the corresponding thin films still do not exhibit a near-unity quantum yield. Herein, we report that the direct addition of a minute amount of water to post-treated substantially enhances the stability while achieving a 95% photoluminescence quantum yield in a NC thin film. We unveil the mechanism of how moisture assists in the formation of an additional NH4Br component. Alongside, we demonstrate the crucial role of moisture in assisting localized etching of the perovskite crystal, facilitating the partial incorporation of NH4+, which is key for improved performance under ambient conditions. Finally, as a proof-of-concept, the application of post-treated and watertreated perovskites is tested in LEDs, with the latter exhibiting a superior performance, offering opportunities toward commercial application in moisture-stable optoelectronics. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000931729400001 |
Publication Date |
2023-01-27 |
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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 |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.5 |
Times cited |
3 |
Open Access |
Not_Open_Access |
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Notes |
H.B. would like to express her sincere gratitude to Dr. Peter Erk (formerly BASF SE, Germany) for very insightful discussions. The authors acknowledge financial support from the Research Foundation-Flanders (FWO grant numbers S002019N, 1514220N, G.0B39.15, G.0B49.15, G098319N, and ZW15_09-GOH6316) , the KU Leuven Research Fund (C14/19/079, iBOF-21-085 PERSIST, and STG/21/010) , the Flemish government through long-term structural funding Methusalem (CASAS2, Meth/15/04) , the Hercules Founda-tion (HER/11/14) , and the ERC through the Marie Curie ITN iSwitch Ph.D. fellowship to H.B. (grant number 642196) . C.M. acknowledges the financial support from grants PID2021-128761OA-C22 funded by MCIN/AEI/10.13039/501100011033 by the ?European Union? and SBPLY/21/180501/000127 funded by JCCM and by the EU through Fondo Europeo de Desarollo Regional? (FEDER) . Martin Bremholm and Martin Ottesen acknowledge funding from the Danish Council for Independent Research, Natural Sciences, under the Sapere Aude program (grant no. 7027-00077B) and VILLUM FONDEN through the Centre of Excellence for Dirac Materials (grant no. 11744) . Affiliation with the Center for Integrated Materials Research (iMAT) at Aarhus University is gratefully acknowledged.-N.J.S. acknowledges financial support from the research foundation Flanders (FWO) through a postdoctoral fellowship (FWO grant no. 1238622N) . S.B. acknowledges financial support from the European Commission by the ERC Consolidator grant REALNANO (no. 815128) . |
Approved |
Most recent IF: 9.5; 2023 IF: 7.504 |
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Call Number |
UA @ admin @ c:irua:195375 |
Serial |
7293 |
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Author |
Paulus, A.; Hendrickx, M.; Bercx, M.; Karakulina, O.M.; Kirsanova, M.A.; Lamoen, D.; Hadermann, J.; Abakumov, A.M.; Van Bael, M.K.; Hardy, A. |
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Title |
An in-depth study of Sn substitution in Li-rich/Mn-rich NMC as a cathode material for Li-ion batteries |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
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| |
Volume |
49 |
Issue |
30 |
Pages |
10486-10497 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Layered Li-rich/Mn-rich NMC (LMR-NMC) is characterized by high initial specific capacities of more than 250 mA h g(-1), lower cost due to a lower Co content and higher thermal stability than LiCoO2. However, its commercialisation is currently still hampered by significant voltage fade, which is caused by irreversible transition metal ion migration to emptied Li positionsviatetrahedral interstices upon electrochemical cycling. This structural change is strongly correlated with anionic redox chemistry of the oxygen sublattice and has a detrimental effect on electrochemical performance. In a fully charged state, up to 4.8 Vvs.Li/Li+, Mn4+ is prone to migrate to the Li layer. The replacement of Mn4+ for an isovalent cation such as Sn4+ which does not tend to adopt tetrahedral coordination and shows a higher metal-oxygen bond strength is considered to be a viable strategy to stabilize the layered structure upon extended electrochemical cycling, hereby decreasing voltage fade. The influence of Sn4+ on the voltage fade in partially charged LMR-NMC is not yet reported in the literature, and therefore, we have investigated the structure and the corresponding electrochemical properties of LMR-NMC with different Sn concentrations. We determined the substitution limit of Sn4+ in Li1.2Ni0.13Co0.13Mn0.54-xSnxO2 by powder X-ray diffraction and transmission electron microscopy to be x approximate to 0.045. The limited solubility of Sn is subsequently confirmed by density functional theory calculations. Voltage fade for x= 0 andx= 0.027 has been comparatively assessed within the 3.00 V-4.55 V (vs.Li/Li+) potential window, from which it is concluded that replacing Mn4+ by Sn4+ cannot be considered as a viable strategy to inhibit voltage fade within this window, at least with the given restricted doping level. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000555330900018 |
Publication Date |
2020-07-09 |
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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 |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
; The authors acknowledge Research Foundation Flanders (FWO) project number G040116N for funding. The authors are grateful to Dr Ken Elen and Greet Cuyvers (imo-imomec, UHasselt and imec) for respectively preliminary PXRD measurements and performing ICP-AES on the monometal precursors. Dr Dmitry Rupasov (Skolkovo Institute of Science and Technology) is acknowledged for performing TGA measurements on the metal sulfate precursors. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 4; 2020 IF: 4.029 |
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Call Number |
UA @ admin @ c:irua:171149 |
Serial |
6450 |
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Author |
Paulus, A.; Hendrickx, M.; Mayda, S.; Batuk, M.; Reekmans, G.; von Holst, M.; Elen, K.; Abakumov, A.M.; Adriaensens, P.; Lamoen, D.; Partoens, B.; Hadermann, J.; Van Bael, M.K.; Hardy, A. |
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Title |
Understanding the Activation of Anionic Redox Chemistry in Ti4+-Substituted Li2MnO3as a Cathode Material for Li-Ion Batteries |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
ACS Appl. Energy Mater. |
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Volume |
6 |
Issue |
13 |
Pages |
6956-6971 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Layered Li-rich oxides, demonstrating both cationic and anionic redox chemistry being used as positive electrodes for Li-ion batteries,have raised interest due to their high specific discharge capacities exceeding 250 mAh/g. However, irreversible structural transformations triggered by anionic redox chemistry result in pronounced voltagefade (i.e., lowering the specific energy by a gradual decay of discharge potential) upon extended galvanostatic cycling. Activating or suppressing oxygen anionic redox through structural stabilization induced by redox-inactivecation substitution is a well-known strategy. However, less emphasishas been put on the correlation between substitution degree and theactivation/suppression of the anionic redox. In this work, Ti4+-substituted Li2MnO3 was synthesizedvia a facile solution-gel method. Ti4+ is selected as adopant as it contains no partially filled d-orbitals. Our study revealedthat the layered “honeycomb-ordered” C2/m structure is preserved when increasing the Ticontent to x = 0.2 in the Li2Mn1-x Ti (x) O-3 solidsolution, as shown by electron diffraction and aberration-correctedscanning transmission electron microscopy. Galvanostatic cycling hintsat a delayed oxygen release, due to an improved reversibility of theanionic redox, during the first 10 charge-discharge cyclesfor the x = 0.2 composition compared to the parentmaterial (x = 0), followed by pronounced oxygen redoxactivity afterward. The latter originates from a low activation energybarrier toward O-O dimer formation and Mn migration in Li2Mn0.8Ti0.2O3, as deducedfrom first-principles molecular dynamics (MD) simulations for the“charged” state. Upon lowering the Ti substitution to x = 0.05, the structural stability was drastically improvedbased on our MD analysis, stressing the importance of carefully optimizingthe substitution degree to achieve the best electrochemical performance. |
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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 |
001018266700001 |
Publication Date |
2023-07-10 |
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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 |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
2574-0962 |
ISBN |
|
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: Available from 24.12.2023 |
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| |
Notes |
Universiteit Hasselt, AUHL/15/2 – GOH3816N ; Russian Science Foundation, 20-43-01012 ; Fonds Wetenschappelijk Onderzoek, AUHL/15/2 – GOH3816N G040116N ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 6.4; 2023 IF: NA |
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| |
Call Number |
EMAT @ emat @c:irua:198160 |
Serial |
8809 |
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| Permanent link to this record |
| |
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| |
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Author |
Mikhailova, D.; Karakulina, O.M.; Batuk, D.; Hadermann, J.; Abakumov, A.M.; Herklotz, M.; Tsirlin, A.A.; Oswald, S.; Giebeler, L.; Schmidt, M.; Eckert, J.; Knapp, M.; Ehrenberg, H. |
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| |
Title |
Layered-to-Tunnel Structure Transformation and Oxygen Redox Chemistry in LiRhO2upon Li Extraction and Insertion |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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| |
Volume |
55 |
Issue |
55 |
Pages |
7079-7089 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Layered Li(M,Li)O2 (where M is a transition metal) ordered rock-salt-type structures are used in advanced metal-ion batteries as one of the best hosts for the reversible intercalation of Li ions. Besides the conventional redox reaction involving oxidation/reduction of the M cation upon Li extraction/insertion, creating oxygen-located holes because of the partial oxygen oxidation increases capacity while maintaining the oxidized oxygen species in the lattice through high covalency of the M–O bonding. Typical degradation mechanism of the Li(M,Li)O2 electrodes involves partially irreversible M cation migration toward the Li positions, resulting in gradual capacity/voltage fade. Here, using LiRhO2 as a model system (isostructural and isoelectronic to LiCoO2), for the first time, we demonstrate an intimate coupling between the oxygen redox and M cation migration. A formation of the oxidized oxygen species upon electrochemical Li extraction coincides with transformation of the layered Li1–xRhO2 structure into the γ-MnO2-type rutile–ramsdellite intergrowth LiyRh3O6 structure with rutile-like [1 × 1] channels along with bigger ramsdellite-like [2 × 1] tunnels through massive and concerted Rh migration toward the empty positions in the Li layers. The oxidized oxygen dimers with the O–O distances as short as 2.26 Å are stabilized in this structure via the local Rh–O configuration reminiscent to that in the μ-peroxo-μ-hydroxo Rh complexes. The LiyRh3O6 structure is remarkably stable upon electrochemical cycling illustrating that proper structural implementation of the oxidized oxygen species can open a pathway toward deliberate employment of the anion redox chemistry in high-capacity/high-voltage positive electrodes for metal-ion batteries. Upon chemical or electrochemical oxidation, layered LiRhO2 shows a unique structural transformation that involves both cation migration and oxidation of oxygen resulting in a stable tunnel-like rutile−ramsdellite intergrowth LiyRh3O6 structure. This structure demonstrates excellent performance with the steady and reversible capacity of ∼200 mAh/g. The stability of LiyRh3O6 is rooted in the accommodation of partially oxidized oxygen species through the formation of short O−O distances that are compatible with the connectivity of RhO6 octahedra. |
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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 |
000380181400035 |
Publication Date |
2016-07-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
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| |
ISSN |
0020-1669 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.857 |
Times cited |
12 |
Open Access |
|
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| |
Notes |
Bundesministerium fur Bildung und Forschung, 03SF0477B ; Fonds Wetenschappelijk Onderzoek, G040116N ; |
Approved |
Most recent IF: 4.857 |
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| |
Call Number |
EMAT @ emat @ c:irua:140848 |
Serial |
4424 |
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| Permanent link to this record |
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Author |
Prabhakara, V.; Jannis, D.; Guzzinati, G.; Béché, A.; Bender, H.; Verbeeck, J. |
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Title |
HAADF-STEM block-scanning strategy for local measurement of strain at the nanoscale |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
219 |
Issue |
|
Pages |
113099 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Lattice strain measurement of nanoscale semiconductor devices is crucial for the semiconductor industry as strain substantially improves the electrical performance of transistors. High resolution scanning transmission electron microscopy (HR-STEM) imaging is an excellent tool that provides spatial resolution at the atomic scale and strain information by applying Geometric Phase Analysis or image fitting procedures. However, HR-STEM images regularly suffer from scanning distortions and sample drift during image acquisition. In this paper, we propose a new scanning strategy that drastically reduces artefacts due to drift and scanning distortion, along with extending the field of view. It consists of the acquisition of a series of independent small subimages containing an atomic resolution image of the local lattice. All subimages are then analysed individually for strain by fitting a nonlinear model to the lattice images. The method allows flexible tuning of spatial resolution and the field of view within the limits of the dynamic range of the scan engine while maintaining atomic resolution sampling within the subimages. The obtained experimental strain maps are quantitatively benchmarked against the Bessel diffraction technique. We demonstrate that the proposed scanning strategy approaches the performance of the diffraction technique while having the advantage that it does not require specialized diffraction cameras. |
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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 |
000594768500006 |
Publication Date |
2020-09-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
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| |
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.2 |
Times cited |
4 |
Open Access |
OpenAccess |
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Notes |
A.B. D.J. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. J.V acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. The Qu-Ant-EM microscope and the direct electron detector used in the diffraction experiments was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the GOA project “Solarpaint” of the University of Antwerp. GG acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek – Vlaanderen (FWO). Special thanks to Dr. Thomas Nuytten, Prof. Dr. Wilfried Vandervorst, Dr. Paola Favia, Dr. Olivier Richard from IMEC, Leuven and Prof. Dr. Sara Bals from EMAT, Antwerp for their continuous support and collaboration with the project and to the IMEC processing group for the device fabrication. |
Approved |
Most recent IF: 2.2; 2020 IF: 2.843 |
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Call Number |
EMAT @ emat @c:irua:172485 |
Serial |
6404 |
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| Permanent link to this record |
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Author |
Schryvers, D.; Tirry, W.; Yang, Z. |
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Title |
Advanced TEM investigations on Ni-Ti shape memory material: strain and concentration gradients surrounding Ni4Ti3 precipitates |
Type |
P1 Proceeding |
| |
Year |
2005 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
329-338 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
Lattice deformations and concentration gradients surrounding Ni4Ti3 precipitates grown by appropriate annealing in a Ni51Ti49 B2 austenite matrix are determined by a combination of TEM techniques. Quantitative Fourier analysis of HRTEM images reveals a deformed nanoscale region with lattice deformations up to 2% while EELS and EDX indicate a Ni depleted zone up to 150 nm away from the matrix-precipitate interface. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
s.l. |
Editor |
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Language |
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Wos |
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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 |
1-55899-790-3 |
ISBN |
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Additional Links |
UA library record; WoS full 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:55688 |
Serial |
75 |
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| Permanent link to this record |
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Author |
Du, C.; Hoefnagels, J.P.M.; Kolling, S.; Geers, M.G.D.; Sietsma, J.; Petrov, R.; Bliznuk, V.; Koenraad, P.M.; Schryvers, D.; Amin-Ahmadi, B. |
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Title |
Martensite crystallography and chemistry in dual phase and fully martensitic steels |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Materials characterization |
Abbreviated Journal |
Mater Charact |
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Volume |
139 |
Issue |
|
Pages |
411-420 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Lath martensite is important in industry because it is the key strengthening component in many advanced high strength steels. The study of crystallography and chemistry of lath martensite is extensive in the literature, however, mostly based on fully martensitic steels. In this work, lath martensite in dual phase steels is investigated with a focus on the substructure identification of the martensite islands and microstructural bands using electron backscattered diffraction, and on the influence of the accompanied tempering process during industrial coating process on the distribution of alloying elements using atom probe tomography. Unlike findings for the fully martensitic steels, no martensite islands with all 24 Kurdjumov-Sachs variants have been observed. Almost all martensite islands contain only one main packet with all six variants and minor variants from the remaining three packets of the same prior austenite grain. Similarly, the martensite bands are typically composed of connected domains originating from prior austenite grains, each containing one main packets (mostly with all variants) and few separate variants. The effect of tempering at similar to 450 degrees C (due to the industrial zinc coating process) has also been investigated. The results show a strong carbon partitioning to lath boundaries and Cottrell atmospheres at dislocation core regions due to the thermal process of coating. In contrast, auto-tempering contributes to the carbon redistribution only in a limited manner. The substitutional elements are all homogenously distributed. The phase transformation process has two effects on the material: mechanically, the earlier-formed laths are larger and softer and therefore more ductile (as revealed by nanoindentation); chemically, due to the higher dislocation density inside the later-formed laths, which are generally smaller, carbon Cottrell atmospheres are predominantly observed. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000431469300044 |
Publication Date |
2018-03-09 |
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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 |
1044-5803 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.714 |
Times cited |
|
Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 2.714 |
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Call Number |
UA @ lucian @ c:irua:151554 |
Serial |
5033 |
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Author |
Zhang, F.; Vanmeensel, K.; Batuk, M.; Hadermann, J.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J. |
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Title |
Highly-translucent, strong and aging-resistant 3Y-TZP ceramics for dental restoration by grain boundary segregation |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Acta biomaterialia |
Abbreviated Journal |
Acta Biomater |
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Volume |
16 |
Issue |
16 |
Pages |
215-222 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Latest trends in dental restorative ceramics involve the development of full-contour 3Y-TZP ceramics which can avoid chipping of veneering porcelains. Among the challenges are the low translucency and the hydrothermal stability of 3Y-TZP ceramics. In this work, different trivalent oxides (Al2O3, Sc2O3, Nd2O3 and La2O3) were selected to dope 3Y-TZP ceramics. Results show that dopant segregation was a key factor to design hydrothermally stable and high-translucent 3Y-TZP ceramics and the cation dopant radius could be used as a controlling parameter. A large trivalent dopant, oversized as compared to Zr4+, exhibiting strong segregation at the ZrO2 grain boundary was preferred. The introduction of 0.2 mol% La2O3 in conventional 0.10.25 wt.% Al2O3-doped 3Y-TZP resulted in an excellent combination of high translucency and superior hydrothermal stability, while retaining excellent mechanical properties. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
S.l. |
Editor |
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Language |
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Wos |
000351978600021 |
Publication Date |
2015-02-04 |
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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 |
1742-7061; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.319 |
Times cited |
54 |
Open Access |
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Notes |
Fwo G043110n |
Approved |
Most recent IF: 6.319; 2015 IF: 6.025 |
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Call Number |
c:irua:124421 |
Serial |
1473 |
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Author |
Yang, T.; Perkisas, T.; Hadermann, J.; Croft, M.; Ignatov, A.; Greenblatt, M. |
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Title |
B-site ordered perovskite LaSrMnNbO6 : synthesis, structure and antiferromagnetism |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
183 |
Issue |
11 |
Pages |
2689-2694 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LaSrMnNbO6 has been synthesized by high temperature solid state reaction under 1% H2/Ar dynamic flow. The structure is determined by Rietveld refinement of the powder X-ray diffraction data. It crystallizes in the monoclinic space group P21/n with the unit cell parameters: a=5.69187(12), b=5.74732(10), c=8.07018(15) Å and β=90.0504(29)°, which were also confirmed by electron diffraction. The Mn2+ and Nb5+ ions, whose valence states are confirmed by X-ray absorption near-edge spectroscopy, are almost completely ordered over the B-site (<1% inversion) of the perovskite structure due to the large differences of both cationic size (0.19 Å) and charge. The octahedral framework displays significant tilting distortion according to Glazers tilt system a−b−c+. Upon heating, LaSrMnNbO6 decomposes at 690 °C under O2 flow or at 775 °C in air. The magnetic susceptibility data indicate the presence of long-range antiferromagnetic ordering at TN=8 K; the experimentally observed effective paramagnetic moment, μeff=5.76 μB for high spin Mn2+ (3d5, S=5/2) is in good agreement with the calculated value (μcalcd=5.92 μB). |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000284179800028 |
Publication Date |
2010-09-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
13 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.299; 2010 IF: 2.261 |
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Call Number |
UA @ lucian @ c:irua:85805 |
Serial |
212 |
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Author |
Savchenko, T.M.; Buzzi, M.; Howald, L.; Ruta, S.; Vijayakumar, J.; Timm, M.; Bracher, D.; Saha, S.; Derlet, P.M.; Béché, A.; Verbeeck, J.; Chantrell, R.W.; Vaz, C.A.F.; Nolting, F.; Kleibert, A. |
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Title |
Single femtosecond laser pulse excitation of individual cobalt nanoparticles |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
102 |
Issue |
20 |
Pages |
205418 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Laser-induced manipulation of magnetism at the nanoscale is a rapidly growing research topic with potential for applications in spintronics. In this work, we address the role of the scattering cross section, thermal effects, and laser fluence on the magnetic, structural, and chemical stability of individual magnetic nanoparticles excited by single femtosecond laser pulses. We find that the energy transfer from the fs laser pulse to the nanoparticles is limited by the Rayleigh scattering cross section, which in combination with the light absorption of the supporting substrate and protective layers determines the increase in the nanoparticle temperature. We investigate individual Co nanoparticles (8 to 20 nm in size) as a prototypical model system, using x-ray photoemission electron microscopy and scanning electron microscopy upon excitation with single femtosecond laser pulses of varying intensity and polarization. In agreement with calculations, we find no deterministic or stochastic reversal of the magnetization in the nanoparticles up to intensities where ultrafast demagnetization or all-optical switching is typically reported in thin films. Instead, at higher fluences, the laser pulse excitation leads to photo-chemical reactions of the nanoparticles with the protective layer, which results in an irreversible change in the magnetic properties. Based on our findings, we discuss the conditions required for achieving laser-induced switching in isolated nanomagnets. |
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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 |
000589602000005 |
Publication Date |
2020-11-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
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Edition |
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| |
ISSN |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
3.7 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
This work received funding by the Swiss National Foundation (SNF) (Grants No. 200021160186 and No. 2002153540), the Swiss Nanoscience Institute (SNI) (Grant No. SNI P1502), the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 737093 (FEMTOTERABYTE), and the COST Action CA17123 (MAGNETOFON). Part of this work was performed at the SIM beamline of the Swiss Light Source (SLS), Paul Scherrer Institut, Villigen, Switzerland. Part of the simulations were undertaken on the VIKING cluster, which is a high-performance compute facility provided by the University of York. We kindly acknowledge Anja Weber from PSI for preparation of substrates with marker structures. A.B. and Jo Verbeeck acknowledge funding through FWO Project No. G093417N (“Compressed sensing enabling low dose imaging in transmission electron microscopy”) from the Flanders Research Fund. Jo Verbeeck acknowledges funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717 – ESTEEM3. S.S. acknowledges ETH Zurich Post-Doctoral fellowship and Marie Curie actions for people COFUND program.; esteem3JRA; esteem3reported |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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Call Number |
EMAT @ emat @c:irua:174273 |
Serial |
6669 |
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Author |
Teodorescu, V.S.; Nistor, L.C.; van Landuyt, J.; Dinescu, M. |
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Title |
TEM study of laser induced phase transition in iron thin films |
Type |
A1 Journal article |
| |
Year |
1994 |
Publication |
Materials research bulletin |
Abbreviated Journal |
Mater Res Bull |
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Volume |
29 |
Issue |
1 |
Pages |
63-71 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Laser induced phase transition from b.c.c.(alpha) to f.c.c.(gamma) iron thin films is studied by high resolution TEM. The iron film has been covered on both sides with carbon layers to protect it against oxidation. Single pulse, tau FWHM = 20ns KrF (lambda = 248nm) excimer laser irradiation was performed in air with the film on the substrate. The laser pulse acts like a heat pulse followed by a rapid quenching revealing sequential aspects of the phase transition process. The presence of a fine mixture of the alpha + gamma phases between the alpha and gamma regions of the film has been interpreted as an incomplet transformation. The results are explained by assuming that the transformation took place via a phonon drag mechanism. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
A1994ML03000008 |
Publication Date |
2003-06-21 |
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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 |
0025-5408; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.288 |
Times cited |
2 |
Open Access |
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| |
Notes |
|
Approved |
no |
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| |
Call Number |
UA @ lucian @ c:irua:99945 |
Serial |
3488 |
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| Permanent link to this record |
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Author |
Ercolani, G.; Gorle, C.; Garcia Sánchez, C.; Corbari, C.; Mancini, M. |
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| |
Title |
RAMS and WRF sensitivity to grid spacing in large-eddy simulations of the dry convective boundary layer |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Computers and fluids |
Abbreviated Journal |
Comput Fluids |
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| |
Volume |
123 |
Issue |
123 |
Pages |
54-71 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Large-eddy simulations (LESS) are frequently used to model the planetary boundary layer, and the choice of the grid cell size, numerical schemes and sub grid model can significantly influence the simulation results. In the present paper the impact of grid spacing on LES of an idealized atmospheric convective boundary layer (CBL), for which the statistics and flow structures are well understood, is assessed for two mesoscale models: the Regional Atmospheric Modeling System (RAMS) and the Weather Research and Forecasting model (WRF). Nine simulations are performed on a fixed computational domain (6 x 6 x 2 km), combining three different horizontal (120, 60, 30 m) and vertical (20, 10, 5 m) spacings. The impact of the cell size on the CBL is investigated by comparing turbulence statistics and velocity spectra. The results demonstrate that both WRF and RAMS can perform LES of the CBL under consideration without requiring extremely high computational loads, but they also indicate the importance of adopting a computational grid that is adequate for the numerical schemes and subgrid models used. In both RAMS and WRF a horizontal cell size of 30 m is required to obtain a suitable turbulence reproduction throughout the CBL height. Considering the vertical grid spacing, WRF produced similar results for all the three tested values, while in RAMS it should be ensured that the aspect ratio of the cells does not exceed a value of 3. The two models were found to behave differently in function of the grid resolution, and they have different shortcomings in their prediction of CBL turbulence. WRF exhibits enhanced damping at the smallest scales, while RAMS is prone to the appearance of spurious fluctuations in the flow when the grid aspect ratio is too high. (C) 2015 Elsevier Ltd. 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 |
Oxford |
Editor |
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| |
Language |
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Wos |
000365367500006 |
Publication Date |
2015-10-08 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0045-7930 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.313 |
Times cited |
3 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 2.313; 2015 IF: 1.619 |
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| |
Call Number |
UA @ lucian @ c:irua:130200 |
Serial |
4236 |
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| Permanent link to this record |
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| |
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Author |
Mahr, C.; Kundu, P.; Lackmann, A.; Zanaga, D.; Thiel, K.; Schowalter, M.; Schwan, M.; Bals, S.; Wittstock, A.; Rosenauer, A. |
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| |
Title |
Quantitative determination of residual silver distribution in nanoporous gold and its influence on structure and catalytic performance |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Journal of catalysis |
Abbreviated Journal |
J Catal |
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| |
Volume |
352 |
Issue |
352 |
Pages |
52-58 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Large efforts have been made trying to understand the origin of the high catalytic activity of dealloyed nanoporous gold as a green catalyst for the selective promotion of chemical reactions at low temperatures. Residual silver, left in the sample after dealloying of a gold-silver alloy, has been shown to have a strong influence on the activity of the catalyst. But the question of how the silver is distributed within the porous structure has not finally been answered yet. We show by quantitative energy dispersive X-ray tomography measurements that silver forms clusters that are distributed irregularly, both on the surface and inside the ligaments building up the porous structure. Furthermore, we find that the role of the residual silver is ambiguous. Whereas CO oxidation is supported by more residual silver, methanol oxidation to methyl formate is hindered. Structural characterisation reveals larger ligaments and pores for decreasing residual silver concentration. |
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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 |
000408299600006 |
Publication Date |
2017-05-29 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0021-9517 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
6.844 |
Times cited |
42 |
Open Access |
OpenAccess |
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| |
Notes |
This work was supported by the Deutsche Forschungsgemeinschaft (DFG) under contracts no. RO2057/12-1 (SP 6) and WI4497/1-1 (SP 2) within the research unit FOR2213 (www.nagocat. de) and the European Research Council (ERC Starting Grant No. 335078-COLOURATOMS). (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); ecas_sara |
Approved |
Most recent IF: 6.844 |
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| |
Call Number |
EMAT @ emat @c:irua:144434UA @ admin @ c:irua:144434 |
Serial |
4623 |
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| Permanent link to this record |
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Author |
Narayanan, V.; Lommens, P.; De Buysser, K.; Vanpoucke, D.E.P.; Huehne, R.; Molina, L.; Van Tendeloo, G.; van der Voort, P.; Van Driessche, I. |
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| |
Title |
Aqueous CSD approach for the growth of novel, lattice-tuned LaxCe1-xO\delta epitaxial layers |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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| |
Volume |
22 |
Issue |
17 |
Pages |
8476-8483 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Lanthanumcerium oxide (LCO) films were deposited on Ni-5%W substrates by chemical solution deposition (CSD) from water-based precursors. LCO films containing different ratios of lanthanum and cerium ions (from CeO2 to La2Ce2O7) were prepared. The composition of the layers was optimized towards the formation of LCO buffer layers, lattice-matched with the superconducting YBa2Cu3Oy layer, useful for the development of coated conductors. Single, crack-free LCO layers with a thickness of up to 140 nm could be obtained in a single deposition step. The crystallinity and microstructure of these lattice-matched LCO layers were studied by X-ray diffraction techniques, RHEED and SEM. We find that only layers with thickness below 100 nm show a crystalline top surface although both thick and thin layers show good biaxial texture in XRD. On the most promising layers, AFM and (S)TEM were performed to further evaluate their morphology. The overall surface roughness varies between 3.9 and 7.5 nm, while the layers appear much more dense than the frequently used La2Zr2O7 (LZO) systems, showing much smaller nanovoids (12 nm) than the latter system. Their effective buffer layer action was studied using XPS. The thin LCO layers supported the growth of superconducting YBCO deposited using PLD methods. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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| |
Language |
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Wos |
000302367500044 |
Publication Date |
2012-03-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
24 |
Open Access |
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| |
Notes |
Iap |
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:96960 |
Serial |
148 |
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| Permanent link to this record |
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Author |
Queralto, A.; Graf, D.; Frohnhoven, R.; Fischer, T.; Vanrompay, H.; Bals, S.; Bartasyte, A.; Mathur, S. |
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Title |
LaFeO3 nanofibers for high detection of sulfur-containing gases |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
ACS Sustainable Chemistry and Engineering |
Abbreviated Journal |
Acs Sustain Chem Eng |
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| |
Volume |
7 |
Issue |
7 |
Pages |
6023-6032 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Lanthanum ferrite nanofibers were electrospun from a chemical sol and calcined at 600 degrees C to obtain singlephase LaFeO3 (LFO) perovskite. High-resolution transmission electron microscopy in conjunction with 3D tomographic analysis confirmed an interwoven network of hollow and porous (surface) LFO nanofibers. Owing to their high surface area and p-type behavior, the nanofiber meshes showed high chemoselectivity toward reducing toxic gases (SO2, H2S) that could be reproducibly detected at very low concentrations (<1 ppm), well below the threshold values for occupational safety and health. An increased sensitivity was observed in the temperature range of 150-300 degrees C with maximum sensor response at 250 degrees C. The surface reaction at the heterogeneous solid (LFO)/gas (SO2) interface that confirmed the formation of La-2(SO4)(3) was investigated by X-ray photoelectron spectroscopy. Moreover, the LFO fibers showed a high selectivity in the detection of oxidizing and reducing gases. Whereas superior detection of NH3 and H2S was measured, little response was observed for CO and NO2. Finally, the integration of nanowire meshes in commercial sensor platforms was successfully demonstrated. |
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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 |
000461978200047 |
Publication Date |
2019-02-21 |
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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 |
2168-0485 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.951 |
Times cited |
41 |
Open Access |
OpenAccess |
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| |
Notes |
; The authors kindly acknowledge the ERA.Net RUS Plus project FONSENS funded by the German Federal Ministry of Education and Research (BMBF) under the grant no. 01DJ16017. A.Q. highly appreciates the support of the Alexander von Humboldt Foundation (grant no. AVH 1184642) and the BMBF for his postdoctoral fellowship. A.Q., D.G., R.F., T.F., and S.M. also kindly acknowledge the financial support of the University of Cologne. H.V. acknowledges financial support by the Research Foundation Flanders (FWO grant 1S32617N). S.B. acknowledges financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS). We also express our gratitude to Prof. Dr. J. Hadermann from the Electron Microscopy for Materials Science group at the University of Antwerp for her assistance. A.B. is grateful for the EUR EIPHI program (grant no. ANR-17-EURE-0002). ; |
Approved |
Most recent IF: 5.951 |
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| |
Call Number |
UA @ admin @ c:irua:158535 |
Serial |
5263 |
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| Permanent link to this record |
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Author |
Bervoets, A.R.J.; Behets, G.J.; Schryvers, D.; Roels, F.; Yang, Z.; Verberckmoes, S.C.; Damment, S.J.P.; Dauwe, S.; Mubiana, V.K.; Blust, R.; de Broe, M.E.; d' Haese, P.C. |
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Title |
Hepatocellular transport and gastrointestinal absorption of lanthanum in chronic renal failure |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Kidney international |
Abbreviated Journal |
Kidney Int |
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| |
Volume |
75 |
Issue |
|
Pages |
389-398 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Pathophysiology |
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Abstract |
Lanthanum carbonate is a new phosphate binder that is poorly absorbed from the gastrointestinal tract and eliminated largely by the liver. After oral treatment, we and others had noticed 23 fold higher lanthanum levels in the livers of rats with chronic renal failure compared to rats with normal renal function. Here we studied the kinetics and tissue distribution, absorption, and subcellular localization of lanthanum in the liver using transmission electron microscopy, electron energy loss spectrometry, and X-ray fluoresence. We found that in the liver lanthanum was located in lysosomes and in the biliary canal but not in any other cellular organelles. This suggests that lanthanum is transported and eliminated by the liver via a transcellular, endosomal-lysosomal-biliary canicular transport route. Feeding rats with chronic renal failure orally with lanthanum resulted in a doubling of the liver levels compared to rats with normal renal function, but the serum levels were similar in both animal groups. These levels plateaued after 6 weeks at a concentration below 3 g/g in both groups. When lanthanum was administered intravenously, thereby bypassing the gastrointestinal tract-portal vein pathway, no difference in liver levels was found between rats with and without renal failure. This suggests that there is an increased gastrointestinal permeability or absorption of oral lanthanum in uremia. Lanthanum levels in the brain and heart fluctuated near its detection limit with long-term treatment (20 weeks) having no effect on organ weight, liver enzyme activities, or liver histology. We suggest that the kinetics of lanthanum in the liver are consistent with a transcellular transport pathway, with higher levels in the liver of uremic rats due to higher intestinal absorption. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000263145800009 |
Publication Date |
2008-12-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0085-2538;1523-1755; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.395 |
Times cited |
29 |
Open Access |
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| |
Notes |
Fwo; Iwt |
Approved |
Most recent IF: 8.395; 2009 IF: 6.193 |
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Call Number |
UA @ lucian @ c:irua:72290 |
Serial |
1417 |
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| Permanent link to this record |
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Author |
Mulder, J.T.T.; Jenkinson, K.; Toso, S.; Prato, M.; Evers, W.H.H.; Bals, S.; Manna, L.; Houtepen, A.J.J. |
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Title |
Nucleation and growth of bipyramidal Yb:LiYF₄ nanocrystals : growing up in a hot environment |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Chemistry of materials |
Abbreviated Journal |
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| |
Volume |
35 |
Issue |
14 |
Pages |
5311-5321 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Lanthanide-doped LiYF4 (Ln:YLF) is commonlyused fora broad variety of optical applications, such as lasing, photon upconversionand optical refrigeration. When synthesized as nanocrystals (NCs),this material is also of interest for biological applications andfundamental physical studies. Until now, it was unclear how Ln:YLFNCs grow from their ionic precursors into tetragonal NCs with a well-defined,bipyramidal shape and uniform dopant distribution. Here, we studythe nucleation and growth of ytterbium-doped LiYF4 (Yb:YLF),as a template for general Ln:YLF NC syntheses. We show that the formationof bipyramidal Yb:YLF NCs is a multistep process starting with theformation of amorphous Yb:YLF spheres. Over time, these spheres growvia Ostwald ripening and crystallize, resulting in bipyramidal Yb:YLFNCs. We further show that prolonged heating of the NCs results inthe degradation of the NCs, observed by the presence of large LiFcubes and small, irregular Yb:YLF NCs. Due to the similarity in chemicalnature of all lanthanide ions our work sheds light on the formationstages of Ln:YLF NCs in general. |
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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 |
001021474500001 |
Publication Date |
2023-07-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0897-4756; 1520-5002 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
8.6 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
This project has received funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 766900 (Testing the large-scale limit of quantum mechanics). The authors thank Niranjan Saikumar for proof reading the manuscript. |
Approved |
Most recent IF: 8.6; 2023 IF: 9.466 |
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| |
Call Number |
UA @ admin @ c:irua:197787 |
Serial |
8907 |
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| Permanent link to this record |
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Author |
Van Hoorebeke, L.; Leroux, O.; Leroux, F.; Mastroberti, A.A.; Santos-Silva, F.; Van Loo, D.; Bagniewska-Zadworna, A.; Bals, S.; Popper, Z.A.; de Araujo Mariath, J.E. |
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Title |
Heterogeneity of silica and glycan-epitope distribution in epidermal idioblast cell walls in Adiantum raddianum laminae |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Planta |
Abbreviated Journal |
Planta |
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| |
Volume |
237 |
Issue |
6 |
Pages |
1453-1464 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Laminae of Adiantum raddianum Presl., a fern belonging to the family Pteridaceae, are characterised by the presence of epidermal fibre-like cells under the vascular bundles. These cells were thought to contain silica bodies, but their thickened walls leave no space for intracellular silica suggesting it may actually be deposited within their walls. Using advanced electron microscopy in conjunction with energy dispersive X-ray microanalysis we showed the presence of silica in the cell walls of the fibre-like idioblasts. However, it was specifically localised to the outer layers of the periclinal wall facing the leaf surface, with the thick secondary wall being devoid of silica. Immunocytochemical experiments were performed to ascertain the respective localisation of silica deposition and glycan polymers. Epitopes characteristic for pectic homogalacturonan and the hemicelluloses xyloglucan and mannan were detected in most epidermal walls, including the silica-rich cell wall layers. The monoclonal antibody, LM6, raised against pectic arabinan, labelled the silica-rich primary wall of the epidermal fibre-like cells and the guard cell walls, which were also shown to contain silica. We hypothesise that the silicified outer wall layers of the epidermal fibre-like cells support the lamina during cell expansion prior to secondary wall formation. This implies that silicification does not impede cell elongation. Although our results suggest that pectic arabinan may be implicated in silica deposition, further detailed analyses are needed to confirm this. The combinatorial approach presented here, which allows correlative screening and in situ localisation of silicon and cell wall polysaccharide distribution, shows great potential for future studies. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000319474200004 |
Publication Date |
2013-02-21 |
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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 |
0032-0935;1432-2048; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.361 |
Times cited |
16 |
Open Access |
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Notes |
We are grateful to the Laboratorio de Anatomia Vegetal of Universidade Federal do Rio Grande do Sul (UFRGS) and the Centro de Microscopia Eletronica (CME) of UFRGS. Thanks to Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) for the undergraduate degree grant provided (PIBIC) for the fourth author and research grant and support for the last one. The third author is grateful to Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) for providing financial support (PRODOC). We acknowledge Christiane de Queiroz Lopes and Moema Queiroz (CME) for the technical assistance. We are indebted to Paul Knox (Centre for Plant Sciences, University of Leeds, UK) for kindly providing the monoclonal antibodies used in this study. The Fund for Scientific Research-Flanders (FWO) is acknowledged for the doctoral grant to D. Van Loo (G.0100.08). |
Approved |
Most recent IF: 3.361; 2013 IF: 3.376 |
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Call Number |
UA @ lucian @ c:irua:109641 |
Serial |
1419 |
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| Permanent link to this record |
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Author |
Yang, T.; Perkisas, T.; Hadermann, J.; Croft, M.; Ignatov, A.; Van Tendeloo, G.; Greenblatt, M. |
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Title |
Synthesis and structure determination of ferromagnetic semiconductors LaAMnSnO6(A = Sr, Ba) |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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Volume |
21 |
Issue |
1 |
Pages |
199-205 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LaAMnSnO(6) (A = Sr, Ba) have been synthesized by high temperature solid-state reactions under dynamic 1% H(2)/Ar flow. Rietveld refinements on room temperature powder X-ray diffraction data indicate that LaSrMnSnO(6) crystallizes in the GdFeO(3)-structure, with space group Pnma and, combined with transmission electron microscopy, LaBaMnSnO(6) in Imma. Both space groups are common in disordered double-perovskites. The Mn(3+) and Sn(4+) ions whose valence states were confirmed by X-ray absorption spectroscopy, are completely disordered over the B-sites and the BO(6) octahedra are slightly distorted. LaAMnSnO(6) are ferromagnetic semiconductors with a T(C) = 83 K for the Sr- and 66 K for the Ba-compound. The title compounds, together with the previously reported LaCaMnSnO(6) provide an interesting example of progression from Pnma to Imma as the tolerance factor increases. An analysis of the relationship between space group and tolerance factor for the series LaAMnMO(6) (A = Ca, Sr, Ba; M = Sn, Ru) provides a better understanding of the symmetry determination for double perovskites. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000285067300025 |
Publication Date |
2010-10-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0959-9428;1364-5501; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
3 |
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:95527 |
Serial |
3440 |
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| Permanent link to this record |
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Author |
Battle, P.D.; Avdeev, M.; Hadermann, J. |
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Title |
The interplay of microstructure and magnetism in La3Ni2SbO9 |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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| |
Volume |
220 |
Issue |
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Pages |
163-166 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
La3Ni2SbO9 adopts a perovskite-related structure in which the six-coordinate cation sites are occupied alternately by Ni2+ and a disordered arrangement of Ni2+/Sb5+. A polycrystalline sample has been studied by neutron diffraction in applied magnetic fields of 0 <= H/kOe <= 50 at 5 K. In 0 kOe, weak magnetic Bragg scattering consistent with the adoption of a G-type ferrimagnetic structure is observed; the ordered component of the magnetic moment was found to be 0.89(7) mu(B) per Ni2+ cation. This increased to 1.60(3) mu(B) in a field of 50 kOe. Transmission electron microscopy revealed variations in the Ni:Sb ratio across crystallites of the sample. It is proposed that these composition variations disrupt the magnetic superexchange interactions within the compound, leading to domain formation and a reduced average moment. The application of a magnetic field aligns the magnetisation vectors across the crystal and the average moment measured by neutron diffraction increases accordingly. The role played by variations in the local chemical composition in determining the magnetic properties invites comparison with the behaviour of relaxor ferroelectrics. (C) 2014 Elsevier Inc. 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 |
London |
Editor |
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Language |
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Wos |
000343346100024 |
Publication Date |
2014-09-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.299; 2014 IF: 2.133 |
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Call Number |
UA @ lucian @ c:irua:121134 |
Serial |
3588 |
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| Permanent link to this record |
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Author |
Chin, C.-M.; Battle, P.D.; Hunter, E.C.; Avdeev, M.; Hendrickx, M.; Hadermann, J. |
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Title |
Stabilisation of magnetic ordering in La3Ni2-xCuxB'O9(B'=Sb,Ta,Nb) by the introduction of Cu2+ |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
276 |
Issue |
276 |
Pages |
164-172 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
La3Ni2-xCuxB'O-9 (x = 0.25; B' = Sb, Ta, Nb: x = 0.5; B' = Nb) have been synthesized and characterised by transmission electron microscopy, neutron diffraction and magnetometry. Each adopts a perovskite-like structure (space group P2(1)/n) with two crystallographically-distinct six-coordinate sites, one occupied by a disordered arrangement of Ni2+ and Cu2+ and the other by a disordered similar to 1:2 distribution of Ni2+ and B'(5+), although some Cu2+ is found on the latter site when x = 0.5. Each composition undergoes a magnetic transition in the range 90 <= T/K <= 130 and shows a spontaneous magnetisation at 5 K; the transition temperature always exceeds that of the x = 0 composition by >= 30 K. A long-range ordered G-type ferrimagnetic structure is present in each composition, but small relaxor domains are also present. This contrasts with the pure relaxor and spin-glass behaviour of x = 0, B' = Ta, Nb, respectively. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000473372400023 |
Publication Date |
2019-05-09 |
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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 |
0022-4596 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
2 |
Open Access |
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Notes |
; We thank EPSRC for funding through grant EP/M0189541. CMC thanks the Croucher Foundation and the University of Oxford for the award of a graduate scholarship. ; |
Approved |
Most recent IF: 2.299 |
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Call Number |
UA @ admin @ c:irua:161199 |
Serial |
5396 |
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Author |
Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Rozova, M.G.; Sarakinou, E.; Antipov, E.V. |
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Title |
Expanding the Ruddlesden-Popper manganite family : the n=3 La3.2Ba0.8Mn3O10 Member |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
21 |
Pages |
11487-11492 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
La3.2Ba0.8Mn3O10, a representative of the rare n = 3 members of the Ruddlesden-Popper manganites A(n+1)Mn(n)O(3n+1), was synthesized in an evacuated sealed silica tube. Its crystal structure was refined from a combination of powder X-ray diffraction (PXD) and precession electron diffraction (PED) data, with the rotations of the MnO6 octahedra described within the symmetry-adapted mode approach (space group Cccm, a = 29.068(1) angstrom, b = 5.5504(5) angstrom, c = 5.5412(5) angstrom; PXD RF = 0.053, RP = 0.026; PED RF = 0.248). The perovskite block in La3.2Ba0.8Mn3O10 features an octahedral tilting distortion with out-of-phase rotations of the Mn06 octahedra according to the (Phi,Phi,0)(Phi,Phi,0) mode, observed for the first time in the n = 3 Ruddlesden-Popper structures. The Mn06 octahedra demonstrate a noticeable deformation with the elongation of two apical Mn-O bonds due to the Jahn-Teller effect in the Mn3+ cations. The relationships between the octahedral tilting distortion, the ionic radii of the cations at the A- and B-positions, and the mismatch between the perovslcite and rock-salt blocks of the Ruddlesden-Popper structure are discussed. At low temperatures, La3.2Ba0.8Mn3O10 reveals a sizable remnant magnetization of about 1.3 mu(B)/Mn at 2K, and shows signatures of spin freezing below 150 K. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000313220200036 |
Publication Date |
2012-10-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0020-1669;1520-510X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:110121 |
Serial |
1133 |
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Author |
Istomin, S.Y.; Morozov, A.V.; Abdullayev, M.M.; Batuk, M.; Hadermann, J.; Kazakov, S.M.; Sobolev, A.V.; Presniakov, I.A.; Antipov, E.V. |
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Title |
High-temperature properties of (La,Ca)(Fe,Mg,Mo)O3-\delta perovskites as prospective electrode materials for symmetrical SOFC |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
258 |
Issue |
258 |
Pages |
1-10 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
La1-yCayFe0.5+x(Mg,Mo)(0.5-x)O3-delta oxides with the orthorhombic GdFeO3-type perovskite structure have been synthesized at 1573 K. Transmission electron microscopy study for selected samples shows the coexistence of domains of perovskite phases with ordered and disordered B-cations. Mossbauer spectroscopy studies performed at 300 K and 573 K show that while compositions with low Ca-content (La0.55Ca0.45Fe0.5Mg0.2625Mo0.2375O3-delta and La0.5Ca0.5Fe0.6Mg0.175Mo0.225O3-delta) are nearly oxygen stoichiometric, La0.2Ca0.8Fe0.5Mg0.2625Mo0.2375O3-delta is oxygen deficient with delta approximate to 0.15. Oxides are stable in reducing atmosphere (Ar/H-2, 8%) at 1173 K for 12 h. No additional phases have been observed at XRPD patterns of all studied perovskites and Ce1-xGdxO2-x/2 electrolyte mixtures treated at 1173-1373K, while Fe-rich compositions (x >= 0.1) react with Zr1-xYxO2-x/2 electrolyte above 1273 K. Dilatometry studies reveal that all samples show rather low thermal expansion coefficients (TECs) in air of 11.4-12.7 ppm K-1. In reducing atmosphere their TECs were found to increase up to 12.1-15.4 ppm K-1 due to chemical expansion effect. High-temperature electrical conductivity measurements in air and Ar/H-2 atmosphere show that the highest conductivity is observed for Fe- and Ca-rich compositions. Moderate values of electrical conductivity and TEC together with stability towards chemical interaction with typical SOFC electrolytes make novel Fe-containing perovskites promising electrode materials for symmetrical solid oxide fuel cell. |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000423650400001 |
Publication Date |
2017-10-11 |
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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 |
0022-4596 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
5 |
Open Access |
Not_Open_Access |
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Notes |
; This work was financially supported by Russian Science Foundation (project number 16-13-10327). ; |
Approved |
Most recent IF: 2.299 |
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Call Number |
UA @ lucian @ c:irua:149283 |
Serial |
4936 |
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Author |
Lebedev, O.I.; Van Tendeloo, G.; Amelinckx, S.; Leibold, B.; Habermeier, H.U.; Phillipp, F. |
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Title |
Structure and magnetotransport properties of La2/3Ca1/3MnO3 thin films prepared by pulsed laser deposition |
Type |
P1 Proceeding |
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Year |
1998 |
Publication |
Materials Research Society symposium proceedings
T2 – Symposium on Advances in Laser Ablation of Materials at the 1998 MRS, Spring Meeting, April 13-16, 1998, San Francisco, Calif. |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
219-224 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
La1-xCaxMnO3-delta (LCMO) thin films are grown by pulsed laser deposition on a (100) SrTiO3 substrate at temperatures between 530 degrees C and 890 degrees C. The magnetotransport properties show a high negative magnetoresistance and a shift of the maximum of the R(T) curve as function of temperature. The Curie temperature changes with deposition temperature and film quality in the range of 100-220K. The film quality is characterised by X-ray diffraction and transmission electron microscopy (TEM); film and target compositions were verified by atomic emission spectroscopy. The local structure of the film depends on the growth conditions and substrate temperature. TEM reveals a slight distortion of the film leading to a breakdown of the symmetry from orthorhombic to monoclinic. At the highest growth temperatures, a well defined interface is observed within the LCMO film, parallel to the substrate surface; this interface divides the film into two lamellae with a different microstructure. The lamella close to the substrate is perfectly coherent with the substrate, suggesting that it is strained as a result of the lattice parameter mismatch; the upper lamella shows a typical domain structure with unusual translation interfaces characterised by a displacement vector of the type 1/2[010](m) and 1/2[001](m) when referred ten the monoclinic lattice. |
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Corporate Author |
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Publisher |
Materials research society |
Place of Publication |
Warrendale |
Editor |
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Language |
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Wos |
000077696000032 |
Publication Date |
2011-04-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
526 |
Series Issue |
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Edition |
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ISSN |
1946-4274; |
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:95838 |
Serial |
3283 |
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| Permanent link to this record |
