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Author |
Zhou, R.; Zhou, R.; Xian, Y.; Fang, Z.; Lu, X.; Bazaka, K.; Bogaerts, A.; Ostrikov, K.(K.) |
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Title |
Plasma-enabled catalyst-free conversion of ethanol to hydrogen gas and carbon dots near room temperature |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal  |
Chem Eng J |
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Volume |
382 |
Issue |
382 |
Pages |
122745 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Selective conversion of bio-renewable ethanol under mild conditions especially at room temperature remains a major challenge for sustainable production of hydrogen and valuable carbon-based materials. In this study, adaptive non-thermal plasma is applied to deliver pulsed energy to rapidly and selectively reform ethanol in the absence of a catalyst. Importantly, the carbon atoms in ethanol that would otherwise be released into the environment in the form of CO or CO2 are effectively captured in the form of carbon dots (CDs). Three modes of non-thermal spark plasma discharges, i.e. single spark mode (SSM), multiple spark mode (MSM) and gliding spark mode (GSM), provide additional flexibility in ethanol reforming by controlling the processes of energy transfer and distribution, thereby affecting the flow rate, gas content, and energy consumption in H-2 production. A favourable combination of low temperature (< 40 degrees C), attractive conversion rate (gas flow rate of similar to 120 mL/min), high hydrogen yield (H-2 content > 90%), low energy consumption (similar to 0.96 kWh/m(3) H-2) and the effective generation of photoluminescent CDs (which are applicable for bioimaging or biolabelling) in the MSM indicate that the proposed strategy may offer a new carbon-negative avenue for comprehensive utilization of alcohols and mitigating the increasingly severe energy and environmental issues. |
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Wos |
000503381200200 |
Publication Date |
2019-09-07 |
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Series Issue |
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Edition |
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ISSN |
1385-8947; 1873-3212 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
15.1 |
Times cited |
20 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 15.1; 2020 IF: 6.216 |
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Call Number |
UA @ admin @ c:irua:165648 |
Serial |
6318 |
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Author |
Andersen, Ja.; Christensen, Jm.; Østberg, M.; Bogaerts, A.; Jensen, Ad. |
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Title |
Plasma-catalytic dry reforming of methane: Screening of catalytic materials in a coaxial packed-bed DBD reactor |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
397 |
Issue |
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Pages |
125519 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The combination of catalysis with non-thermal plasma is a promising alternative to thermal catalysis. A dielectric-barrier discharge reactor was used to study plasma-catalytic dry reforming of methane at ambient pressure and temperature and a fixed plasma power of 45 W. The effect of different catalytic packing materials was evaluated in terms of conversion, product selectivity, and energy efficiency. The conversion of CO2 (~22%) and CH4 (~33%) were found to be similar in plasma-only and when introducing packing materials in plasma. The main reason is the shorter residence time of the gas due to packing geometry, when compared at identical flow rates. H2, CO, C2-C4 hydrocarbons, and oxygenates were identified in the product gas. High selectivity towards H2 and CO were found for all catalysts and plasma-only, with a H2/CO molar ratio of ~0.9. The lowest syngas selectivity was obtained with Cu/Al2O3 (~66%), which instead, had the highest alcohol selectivity (~3.6%). |
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Wos |
000542296100011 |
Publication Date |
2020-05-17 |
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ISSN |
1385-8947 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
15.1 |
Times cited |
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Open Access |
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Notes |
Department of Chemical and Biochemical Engineering, Technical University of Denmark; We thank Haldor Topsoe A/S for providing all the catalytic materials used and the Department of Chemical and Biochemical Engineering, Technical University of Denmark, for funding this project. |
Approved |
Most recent IF: 15.1; 2020 IF: 6.216 |
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Call Number |
PLASMANT @ plasmant @c:irua:170613 |
Serial |
6406 |
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Author |
Uytdenhouwen, Y.; Hereijgers, J.; Breugelmans, T.; Cool, P.; Bogaerts, A. |
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Title |
How gas flow design can influence the performance of a DBD plasma reactor for dry reforming of methane |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
405 |
Issue |
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Pages |
126618 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
DBD plasma reactors are commonly used in a static ‘one inlet – one outlet’ design that goes against reactor design principles for multi-component reactions, such as dry reforming of methane (DRM). Therefore, in this paper we have developed a novel reactor design, and investigated how the shape and size of the reaction zone, as well as gradual gas addition, and the method of mixing CO2 and CH4 can influence the conversion and product com position of DRM. Even in the standard ‘one inlet – one outlet’ design, the direction of the gas flow (i.e. short or long path through the reactor, which defines the gas velocity at fixed residence time), as well as the dimensions of the reaction zone and the power delivery to the reactor, largely affect the performance. Using gradual gas addition and separate plasma activation zones for the individual gases give increased conversions within the same operational parameters, by optimising mixing ratios and kinetics. The choice of the main (pre-activated) gas and the direction of gas flow largely affect the conversion and energy cost, while the gas inlet position during separate addition only influences the product distribution. |
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Wos |
000626511800005 |
Publication Date |
2020-08-12 |
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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 |
1385-8947 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.216 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Interreg; Flanders; FWO; University of Antwerp; The authors acknowledge financial support from the European Fund for Regional Development through the cross-border collaborative Interreg V program Flanders-the Netherlands (project EnOp), the Fund 13 for Scientific Research (FWO; grant number: G.0254.14N), and an IOFSBO (SynCO2Chem) project from the University of Antwerp. |
Approved |
Most recent IF: 6.216 |
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Call Number |
PLASMANT @ plasmant @c:irua:170609 |
Serial |
6410 |
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Author |
Uytdenhouwen, Y.; Bal, Km.; Neyts, Ec.; Meynen, V.; Cool, P.; Bogaerts, A. |
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Title |
On the kinetics and equilibria of plasma-based dry reforming of methane |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
405 |
Issue |
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Pages |
126630 |
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Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Plasma reactors are interesting for gas-based chemical conversion but the fundamental relation between the plasma chemistry and selected conditions remains poorly understood. Apparent kinetic parameters for the loss and formation processes of individual components of gas conversion processes, can however be extracted by performing experiments in an extended residence time range (2–75 s) and fitting the gas composition to a firstorder kinetic model of the evolution towards partial chemical equilibrium (PCE). We specifically investigated the differences in kinetic characteristics and PCE state of the CO2 dissociation and CH4 reforming reactions in a dielectric barrier discharge reactor (DBD), how these are mutually affected when combining both gases in the dry reforming of methane (DRM) reaction, and how they change when a packing material (non-porous SiO2) is added to the reactor. We find that CO2 dissociation is characterized by a comparatively high reaction rate of 0.120 s−1 compared to CH4 reforming at 0.041 s−1; whereas CH4 reforming reaches higher equilibrium conversions, 82% compared to 53.6% for CO2 dissociation. Combining both feed gases makes the DRM reaction to proceed at a relatively high rate (0.088 s−1), and high conversion (75.4%) compared to CO2 dissociation, through accessing new chemical pathways between the products of CO2 and CH4. The addition of the packing material can also distinctly influence the conversion rate and position of the equilibrium, but its precise effect depends strongly on the gas composition. Comparing different CO2:CH4 ratios reveals the delicate balance of the combined chemistry. CO2 drives the loss reactions in DRM, whereas CH4 in the mixture suppresses back reactions. As a result, our methodology provides some of the insight necessary to systematically tune the conversion process. |
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Wos |
000621197700003 |
Publication Date |
2020-08-12 |
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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 |
1385-8947 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.216 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
The authors acknowledge financial support from the European Fund for Regional Development through the cross-border collaborative Interreg V program Flanders-the Netherlands (project EnOp), the Fund for Scientific Research (FWO; grant number: G.0254.14N), a TOP-BOF project and an IOF-SBO (SynCO2Chem) project from the University of Antwerp. |
Approved |
Most recent IF: 6.216 |
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Call Number |
PLASMANT @ plasmant @c:irua:172458 |
Serial |
6411 |
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Author |
Blommaerts, N.; Hoeven, N.; Arenas Esteban, D.; Campos, R.; Mertens, M.; Borah, R.; Glisenti, A.; De Wael, K.; Bals, S.; Lenaerts, S.; Verbruggen, S.W.; Cool, P. |
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Title |
Tuning the turnover frequency and selectivity of photocatalytic CO2 reduction to CO and methane using platinum and palladium nanoparticles on Ti-Beta zeolites |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
410 |
Issue |
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Pages |
128234 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A Ti-Beta zeolite was used in gas phase photocatalytic CO2 reduction to reduce the charge recombination rate and increase the surface area compared to P25 as commercial benchmark, reaching 607 m2 g-1. By adding Pt nanoparticles, the selectivity can be tuned toward CO, reaching a value of 92% and a turnover frequency (TOF) of 96 µmol.gcat-1.h-1, nearly an order of magnitude higher in comparison with P25. By adding Pd nanoparticles the selectivity can be shifted from CO (70% for a bare Ti-Beta zeolite), toward CH4 as the prevalent species (60%). In this way, the selectivity toward CO or CH4 can be tuned by either using Pt or Pd. The TOF values obtained in this work outperform reported state-of-the-art values in similar research. The improved activity by adding the nanoparticles was attributed to an improved charge separation efficiency, together with a plasmonic contribution of the metal nanoparticles under the applied experimental conditions. |
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Wos |
000623394200004 |
Publication Date |
2021-01-09 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
1385-8947 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.216 |
Times cited |
15 |
Open Access |
OpenAccess |
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Notes |
N.B., S.L., S.W.V. and P.C. wish to thank the Flemish government and Catalisti for financial support and coordination in terms of a sprint SBO in the context of the moonshot project D2M. N.H. thanks the Flanders Innovation and Entrepreneurship (VLAIO) for the financial support. The Systemic Physiological and Ecotoxicological Research (SPHERE) group, R. Blust, University of Antwerp is acknowledged for the ICP-MS measurements. |
Approved |
Most recent IF: 6.216 |
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Call Number |
EMAT @ emat @c:irua:174591 |
Serial |
6662 |
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Author |
Girard-Sahun, F.; Biondo, O.; Trenchev, G.; van Rooij, G.; Bogaerts, A. |
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Title |
Carbon bed post-plasma to enhance the CO2 conversion and remove O2 from the product stream |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
442 |
Issue |
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Pages |
136268 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
CO2 conversion by plasma technology is gaining increasing interest. We present a carbon (charcoal) bed placed after a Gliding Arc Plasmatron (GAP) reactor, to enhance the CO2 conversion, promote O/O2 removal and in crease the CO fraction in the exhaust mixture. By means of an innovative (silo) system, the carbon is constantly supplied, to avoid carbon depletion upon reaction with O/O2. Using this carbon bed, the CO2 conversion is enhanced by almost a factor of two (from 7.6 to 12.6%), while the CO concentration even increases by a factor of three (from 7.2 to 21.9%), and O2 is completely removed from the exhaust mixture. Moreover, the energy ef ficiency of the conversion process drastically increases from 27.9 to 45.4%, and the energy cost significantly drops from 41.9 to 25.4 kJ.L− 1. We also present the temperature as a function of distance from the reactor outlet, as well as the CO2, CO and O2 concentrations and the temperature in the carbon bed as a function of time, which is important for understanding the underlying mechanisms. Indeed, these time-resolved measurements reveal that the initial enhancements in CO2 conversion and in CO concentration are not maintained in our current setup. Therefore, we present a model to study the gasification of carbon with different feed gases (i.e., O2, CO and CO2 separately), from which we can conclude that the oxygen coverage at the surface plays a key role in determining the product composition and the rate of carbon consumption. Indeed, our model insights indicate that the drop in CO2 conversion and in CO concentration after a few minutes is attributed to deactivation of the carbon bed, due to rapid formation of oxygen complexes at the surface. |
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Wos |
000797716700002 |
Publication Date |
0000-00-00 |
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Series Editor |
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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 |
1385-8947 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
15.1 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Horizon 2020 Marie Skłodowska-Curie Actions; European Research Council; This research was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project) and the European Union’s Horizon 2020 Research and Innovation programme under the Marie Sklodowska-Curie grant agreement No 813393 (PIONEER). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit |
Approved |
Most recent IF: 15.1 |
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Call Number |
PLASMANT @ plasmant @c:irua:188286 |
Serial |
7052 |
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Author |
Girard-Sahun, F.; Biondo, O.; Trenchev, G.; van Rooij, G.; Bogaerts, A. |
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Title |
Carbon bed post-plasma to enhance the CO2 conversion and remove O2 from the product stream |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
442 |
Issue |
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Pages |
136268 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
CO2 conversion by plasma technology is gaining increasing interest. We present a carbon (charcoal) bed placed after a Gliding Arc Plasmatron (GAP) reactor, to enhance the CO2 conversion, promote O/O2 removal and in crease the CO fraction in the exhaust mixture. By means of an innovative (silo) system, the carbon is constantly supplied, to avoid carbon depletion upon reaction with O/O2. Using this carbon bed, the CO2 conversion is enhanced by almost a factor of two (from 7.6 to 12.6%), while the CO concentration even increases by a factor of three (from 7.2 to 21.9%), and O2 is completely removed from the exhaust mixture. Moreover, the energy ef ficiency of the conversion process drastically increases from 27.9 to 45.4%, and the energy cost significantly drops from 41.9 to 25.4 kJ.L− 1. We also present the temperature as a function of distance from the reactor outlet, as well as the CO2, CO and O2 concentrations and the temperature in the carbon bed as a function of time, which is important for understanding the underlying mechanisms. Indeed, these time-resolved measurements reveal that the initial enhancements in CO2 conversion and in CO concentration are not maintained in our current setup. Therefore, we present a model to study the gasification of carbon with different feed gases (i.e., O2, CO and CO2 separately), from which we can conclude that the oxygen coverage at the surface plays a key role in determining the product composition and the rate of carbon consumption. Indeed, our model insights indicate that the drop in CO2 conversion and in CO concentration after a few minutes is attributed to deactivation of the carbon bed, due to rapid formation of oxygen complexes at the surface. |
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000797716700002 |
Publication Date |
0000-00-00 |
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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 |
1385-8947 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
15.1 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
Horizon 2020 Marie Skłodowska-Curie Actions; European Research Council; This research was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project) and the European Union’s Horizon 2020 Research and Innovation programme under the Marie Sklodowska-Curie grant agreement No 813393 (PIONEER). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. We also thank R. De Meyer, K. Leyssens and S. Defossé for performing the charcoal characterizations. |
Approved |
Most recent IF: 15.1 |
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Call Number |
PLASMANT @ plasmant @c:irua:188286 |
Serial |
7053 |
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Author |
Van Alphen, S.; Ahmadi Eshtehardi, H.; O'Modhrain, C.; Bogaerts, J.; Van Poyer, H.; Creel, J.; Delplancke, M.-P.; Snyders, R.; Bogaerts, A. |
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Title |
Effusion nozzle for energy-efficient NOx production in a rotating gliding arc plasma reactor |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
443 |
Issue |
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Pages |
136529 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Plasma-based NOx production is of interest for sustainable N2 fixation, but more research is needed to improve its performance. One of the current limitations is recombination of NO back into N2 and O2 molecules immediately after the plasma reactor. Therefore, we developed a novel so-called “effusion nozzle”, to improve the performance of a rotating gliding arc plasma reactor for NOx production, but the same principle can also be applied to other plasma types. Experiments in a wide range of applied power, gas flow rates and N2/O2 ratios demonstrate an enhancement in NOx concentration by about 8%, and a reduction in energy cost by 22.5%. In absolute terms, we obtain NOx concentrations up to 5.9%, at an energy cost down to 2.1 MJ/mol, which are the best values reported to date in literature. In addition, we developed four complementary models to describe the gas flow, plasma temperature and plasma chemistry, aiming to reveal why the effusion nozzle yields better performance. Our simulations reveal that the effusion nozzle acts as very efficient heat sink, causing a fast drop in gas temperature when the gas molecules leave the plasma, hence limiting the recombination of NO back into N2 and O2. This yields an overall higher NOx concentration than without the effusion nozzle. This immediate quenching right at the end of the plasma makes our effusion nozzle superior to more conventional cooling options, like water cooling In addition, this higher NOx concentration can be obtained at a slightly lower power, because the effusion nozzle allows for the ignition and sustainment of the plasma at somewhat lower power. Hence, this also explains the lower energy cost. Overall, our experimental results and detailed modeling analysis will be useful to improve plasma-based NOx production in other plasma reactors as well. |
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Wos |
000800010600003 |
Publication Date |
0000-00-00 |
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Series Editor |
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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 |
1385-8947 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
15.1 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
This research was supported by the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 810182 – SCOPE ERC Synergy project), and through long-term structural funding (Methusalem). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. |
Approved |
Most recent IF: 15.1 |
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Call Number |
PLASMANT @ plasmant @c:irua:188283 |
Serial |
7057 |
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Author |
Wang, Y.; Chen, Y.; Harding, J.; He, H.; Bogaerts, A.; Tu, X. |
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Title |
Catalyst-free single-step plasma reforming of CH4 and CO2 to higher value oxygenates under ambient conditions |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
450 |
Issue |
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Pages |
137860 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Direct conversion of CH4 and CO2 to liquid fuels and chemicals under mild conditions is appealing for biogas conversion and utilization but challenging due to the inert nature of both gases. Herein, we report a promising plasma process for the catalyst-free single-step conversion of CH4 and CO2 into higher value oxygenates (i.e., methanol, acetic acid, ethanol, and acetone) at ambient pressure and room temperature using a water-cooled dielectric barrier discharge (DBD) reactor, with methanol being the main liquid product. The distribution of liquid products could be tailored by tuning the discharge power, reaction temperature and residence time. Lower discharge powers (10–15 W) and reaction temperatures (5–20 ◦ C) were favourable for the production of liquid products, achieving the highest methanol selectivity of 43% at 5 ◦ C and 15 W. A higher discharge power and reaction temperature, on the other hand, produced more gaseous products, particularly H2 (up to 26% selectivity) and CO (up to 33% selectivity). In addition, varying these process parameters (discharge power, reaction temperature and residence time) resulted in a simultaneous change in key discharge properties, such as mean electron energy (Ee), electron density (ne) and specific energy input (SEI), all of which are essential determiners of plasma chemical reactions. According to the results of artificial neural network (ANN) models, the relative importance of these process parameters and key discharge indicators on reaction performance follows the order: discharge power > reaction temperature > residence time, and SEI > ne > Ee, respectively. This work provides new insights into the contributions and tuning mechanism of multiple parameters for optimizing the reaction performance (e.g., liquid production) in the plasma gas conversion process. |
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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 |
000830813300004 |
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 |
1385-8947 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
15.1 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
This project received funding from the European Union’s Horizon 2020 research and innovation program under the Marie SklodowskaCurie grant agreement No. 813393. |
Approved |
Most recent IF: 15.1 |
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| |
Call Number |
PLASMANT @ plasmant @c:irua:189502 |
Serial |
7100 |
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| Permanent link to this record |
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Author |
Lang, X.; Ouyang, Y.; Vandewalle, L.A.; Goshayeshi, B.; Chen, S.; Madanikashani, S.; Perreault, P.; Van Geem, K.M.; van Geem, K.M. |
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| |
Title |
Gas-solid hydrodynamics in a stator-rotor vortex chamber reactor |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
|
| |
Volume |
446 |
Issue |
5 |
Pages |
137323-12 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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| |
Abstract |
The gas-solid vortex reactor (GSVR) has enormous process intensification potential. However the huge gas consumption can be a serious disadvantage for the GSVR in some applications such as fast pyrolysis. In this work, we demonstrate a recent novel design, where a stator-rotor vortex chamber (STARVOC) is driven by the fluid's kinetic energy, to decouple the solids bed rotation and gas. Gas-solid fluidization by using air and monosized aluminum balls was performed to investigate the hydrodynamics. A constructed fluidization flow regime map for a fixed solids loading of 100 g shows that the bed can only be fluidized for a rotation speed between 200 and 400 RPM. Below 200 RPM, particles settle down on the bottom plate and cannot form a stable bed due to inertia and friction. Above 400 RPM, the bed cannot be fluidized with superficial velocities up to 1.8 m/s (air flow rate of 90 Nm(3)/h). The bed thickness shows some non-uniformities, being smaller at the top of the bed than at the bottom counterpart. However by increasing the air flow rate or rotation speed the axial nonuniformity can be resolved. The bed pressure drop first increases with increasing gas flow rate and then levels off, showing similar characteristics as conventional fluidized beds. Theoretical pressure drops calculated from mathematical models such as Kao et al. model agree well with experimental measurements. Particle velocity discrepancies between the top and bottom particles reveal that the impact of gravity cannot be completely neglected. Design guidelines and possible applications for further development of STARVOC concept are proposed based on fundamental data provided in this work. |
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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 |
000833418100006 |
Publication Date |
2022-06-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1385-8947; 1873-3212 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
15.1 |
Times cited |
|
Open Access |
OpenAccess |
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| |
Notes |
|
Approved |
Most recent IF: 15.1 |
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| |
Call Number |
UA @ admin @ c:irua:189283 |
Serial |
7167 |
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| Permanent link to this record |
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Author |
Brienza, F.; Van Aelst, K.; Devred, F.; Magnin, D.; Tschulkow, M.; Nimmegeers, P.; Van Passel, S.; Sels, B.F.; Gerin, P.; Debecker, D.P.; Cybulska, I. |
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Title |
Unleashing lignin potential through the dithionite-assisted organosolv fractionation of lignocellulosic biomass |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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| |
Volume |
450 |
Issue |
3 |
Pages |
138179-14 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) |
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Abstract |
The development of biomass pretreatment approaches that, next to (hemi)cellulose valorization, aim at the conversion of lignin to chemicals is essential for the long-term success of a biorefinery. Herein, we discuss a dithionite-assisted organosolv fractionation (DAOF) of lignocellulose in n-butanol and water to produce cellulosic pulp and mono-/oligo-aromatics. The study frames the technicalities of this biorefinery process and relates them to the features of the obtained product streams. We comprehensively identify and quantify all products of interest: solid pulp (acid hydrolysis-HPLC, ATR-FTIR, XRD, SEM, enzymatic hydrolysis-HPLC), lignin derivatives (GPC, GC-MS/FID, 1H-13C HSQC NMR, ICP-AES), and carbohydrate derivatives (HPLC). These results were used for inspecting the economic feasibility of DAOF. In the best process configuration, a high yield of monophenolics was reached (~20%, based on acid insoluble lignin in birch sawdust). Various other lignocellulosic feedstocks were also explored, showing that DAOF is particularly effective on hardwood and herbaceous biomass. Overall, this study demonstrates that DAOF is a viable fractionation method for the sustainable upgrading of lignocellulosic biomass. |
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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 |
000888204900005 |
Publication Date |
2022-07-20 |
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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 |
1385-8947; 1873-3212 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
15.1 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
|
Approved |
Most recent IF: 15.1 |
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| |
Call Number |
UA @ admin @ c:irua:189322 |
Serial |
7373 |
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| Permanent link to this record |
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Author |
Roegiers, J.; Denys, S. |
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Title |
Development of a novel type activated carbon fiber filter for indoor air purification |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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| |
Volume |
417 |
Issue |
|
Pages |
128109 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
A novel type of activated carbon fiber filter was developed for indoor air purification. The filter is equipped with electrodes for thermo-electrical regeneration at the point of saturation. The electrodes are arranged in such a way that the filter forms a pleated structure with an electrode in the tip of each pleat. This allows for a uniform temperature distribution on the filter surface during the regeneration process and the pleated structure reduces the overall pressure drop across the filter. The latter was validated by Computational Fluid Dynamics, using Darcy-Forchheimer parameters derived in previous work. The CFD model was further used to perform a virtual sensitivity study in search for the optimal ACF filter design by varying the pleat length, pleat height and filter thickness. Finally, adsorption and desorption properties were investigated with acetaldehyde and toluene as model compounds. Freundlich and Langmuir adsorption parameters, derived in previous work were successfully validated with a Multiphysics model. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000653229500132 |
Publication Date |
2020-12-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1385-8947; 1873-3212 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.216 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
|
Approved |
Most recent IF: 6.216 |
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| |
Call Number |
UA @ admin @ c:irua:174105 |
Serial |
7800 |
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| Permanent link to this record |
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Author |
Ma, Z.; Perreault, P.; Pelegrin, D.C.; Boffito, D.C.; Patience, G.S. |
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Title |
Thermodynamically unconstrained forced concentration cycling of methane catalytic partial oxidation over CeO2FeCralloy catalysts |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Chemical Engineering Journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
380 |
Issue |
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Pages |
122470-11 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Converting waste associated natural gas from oil fields is uneconomic with current gas-to-liquid technology. Micro Gas-to-Liquids technology ( GtL) combines process intensification and numbering up economics to reduce capital costs to convert flared and vented natural gas to value-added synthetic fuel: Milli-second contact times in the catalytic partial oxidation of methane (CPOX) integrated with a tandem Fischer-Tropsch (FT) step meets the economic constraints together with remote process control. FeCralloy knitted fibres with high thermal conductivity and low pressure drop, resist thermal and mechanical stresses in the high pressure CPOX step. The FeCralloy catalysts are free of pre-reduction treatments. We deposited Pt and/or CeO2 over the fibre surface via solution combustion synthesis. Methane conversion was higher at ambient pressure compared to 2 MPa while the Pt/CeO2 FeCralloy was relatively inert from 0.1 MPa to 2 MPa. However, both catalysts demonstrated high activity in quasi-chemical looping partial oxidation of methane: during the reduction step while feeding methane, an on-line mass spectrometer only detected H2 while in the oxidation step it detected predominantly CO. Kinetic modeling of the oxidation-reduction cycles suggests that the reaction follows a direct mechanism to produce CO and H2 rather than an indirect mechanism that first produces CO2 and H2O followed by reforming. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2019-08-14 |
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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 |
1385-8947; 1873-3212 |
ISBN |
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Additional Links |
UA library record |
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| |
Impact Factor |
15.1 |
Times cited |
|
Open Access |
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Notes |
|
Approved |
Most recent IF: 15.1; 2020 IF: 6.216 |
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Call Number |
UA @ admin @ c:irua:162119 |
Serial |
8665 |
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| Permanent link to this record |
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Author |
Gonzalez-Quiroga, A.; Shtern, V.; Perreault, P.; Vandewalle, L.; Marin, G.B.; Van Geem, K.M. |
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Title |
Intensifying mass and heat transfer using a high-g stator-rotor vortex chamber |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Chemical Engineering And Processing |
Abbreviated Journal |
Chem Eng Process |
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Volume |
169 |
Issue |
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Pages |
108638-11 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Vortex reactors take advantage of the synergy between enhanced heat and mass transfer rates and multifunctional phenomena at different temporal and spatial scales. Proof-of-concept experiments with our novel and innovative STAtor-Rotor VOrtex Chamber (STARVOC) confirm its advantageous features for the sustainable production of chemicals and fuels. STARVOC is a high-g contactor that uses carrier flow (gas or liquid) tangential injection to drive a rotor attached to low-friction bearings. The vortex chamber inside the rotor contains a secondary phase or phases, such as a solids bed, a liquid layer, or a suspension. Carrier fluid passes through the perforated rotor wall and contacts a densely and uniformly distributed secondary phase with enhanced slip velocities. Experiments focused on pressure profiles, rotor angular velocity, and solids azimuthal velocity. With air as the carrier fluid and different solid particle beds as the secondary phase, STARVOC reached bed azimuthal velocities up to four-fold compared to those reached in Gas-Solid Vortex Units with fully static geometry. These results show its potential to improve interfacial heat and mass transfer rates and take advantage of flow energy and angular momentum. Due to its process intensification capabilities, STARVOC is a promising alternative for the state-of-the-art chemical industry. |
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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 |
000704946900008 |
Publication Date |
2021-09-17 |
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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 |
0255-2701 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.234 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 2.234 |
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Call Number |
UA @ admin @ c:irua:181062 |
Serial |
8111 |
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| Permanent link to this record |
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Author |
Pauwels, D.; Geboes, B.; Hereijgers, J.; Choukroun, D.; De Wael, K.; Breugelmans, T. |
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Title |
The application of an electrochemical microflow reactor for the electrosynthetic aldol reaction of acetone to diacetone alcohol |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Chemical engineering research and design |
Abbreviated Journal |
Chem Eng Res Des |
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Volume |
128 |
Issue |
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Pages |
205-213 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
The design and application of an electrochemical micro-flow reactor for the aldol reaction of acetone to diacetone alcohol (DAA) is reported. The modular reactor could be readily disassembled and reassembled to change the electrodes, incorporate a membrane and remove possible obstructions. The productivity and efficiency was quantified. Using a platinum deposit as electrocatalyst or an inert glassy carbon electrode as working electrode, the maximum obtainable equilibrium concentration of ±15 m% was reached after a single pass up to a flow rate of 8 ml min−1, yielding 0.57 g min−1 DAA (3.46 mmol cm−3 min−1) at an efficiency of 0.33 g C−1 on platinum and 0.50 g min−1 (3.04 mmol cm−3 min−1) at 1.20 g C−1 on glassy carbon. Note that no optimisation studies have been made in the present paper. |
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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 |
000424736500018 |
Publication Date |
2017-10-20 |
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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 |
0263-8762 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.538 |
Times cited |
2 |
Open Access |
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Notes |
; The authors would like to thank Bert De Mot for assisting with the measurements. Jonas Hereijgers greatly acknowledges the Research Foundation – Flanders (FWO) for support through a Post-Doctoral grant (12Q8817N). ; |
Approved |
Most recent IF: 2.538 |
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Call Number |
UA @ admin @ c:irua:146943 |
Serial |
5871 |
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Author |
Bosch, B.; Leleu, M.; Oustrière, P.; Sarcia, C.; Sureau, J.F.; Blommaert, W.; Gijbels, R.; Sadurski, A.; Vandelannoote, R.; Van Grieken, R.; Van 'T Dack, L.; |
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Title |
Hydrogeochemistry in the zinclead mining district of Les Malines (Gard, France) |
Type |
A1 Journal article |
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Year |
1986 |
Publication |
Chemical geology |
Abbreviated Journal |
Chem Geol |
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Volume |
55 |
Issue |
1/2 |
Pages |
31-44 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Sensitive multi-element analysis techniques together with major-element and isotopic analyses were applied to spring, mine and surface waters in the vicinity of an important known zinclead deposit in a carbonate environment, in the Les Malines area (Gard, France). Both the dissolved and suspended phases were investigated, and concretions and sediments were also considered in some cases. This methodological test shows that the ore body leaves various clear fingerprints, such as the Zn, As, Sb, Pb and U levels in the dissolved phase, the sulfate increment and the δ 34S. Some of the elements in solution are controlled by slightly soluble compounds, e.g. Zn by smithsonite and hydrozincite, Ba by barite, and Pb by hydrocerussite. Mapping the saturation indices for these elements appears useful for displaying the hydrogeochemical anomaly. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
A1986C743300003 |
Publication Date |
2003-08-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0009-2541; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.524 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
CRYSTALLOGRAPHY 19/26 Q3 # PHYSICS, CONDENSED MATTER 53/67 Q4 # |
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Call Number |
UA @ lucian @ c:irua:111481 |
Serial |
1537 |
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Author |
Kuckova, S.; Hamidi-Asl, E.; Matulkova, I.; Hynek, R.; De Wael, K.; Sanyova, J.; Janssens, K. |
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Title |
Technoques and applications of Surface-Enhanced Raman Scattering Spectroscopy (SERSS) focused on cultural heritage |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Chemické listy |
Abbreviated Journal |
Chem Listy |
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Volume |
112 |
Issue |
5 |
Pages |
312-316 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The review is devoted to a modern method of vibrational spectroscopy – surface enhanced Raman spectroscopy Its principle and some of its special variants (imunnoSERS and TERS (Tip-Enhanced Raman Spectroscopy)) are described m a simpinified manner Wide application possibilities are demonstrated on selected examples from its application m culturinl heritage. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
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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 |
0009-2770; 1213-7103 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
0.387 |
Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 0.387 |
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Call Number |
UA @ admin @ c:irua:151616 |
Serial |
5869 |
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| Permanent link to this record |
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Author |
Corbel, G.; Attfield, J.P.; Hadermann, J.; Abakumov, A.M.; Alekseeva, A.M.; Rozova, M.G.; Antipov, E.V. |
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Title |
Anion rearrangements in fluorinated Nd2CuO3.5 |
Type |
A1 Journal article |
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Year |
2003 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
15 |
Issue |
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Pages |
189-195 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000180368000029 |
Publication Date |
2003-01-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
9 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 9.466; 2003 IF: 4.374 |
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Call Number |
UA @ lucian @ c:irua:40348 |
Serial |
123 |
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| Permanent link to this record |
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Author |
Casavola, M.; van Huis, M.A.; Bals, S.; Lambert, K.; Hens, Z.; Vanmaekelbergh, D. |
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Title |
Anisotropic cation exchange in PbSe/CdSe core/shell nanocrystals of different geometry |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
24 |
Issue |
2 |
Pages |
294-302 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
We present a study of Cd2+-for-Pb2+ exchange in PbSe nanocrystals (NCs) with cube, star, and rod shapes. Prolonged temperature-activated cation exchange results in PbSe/CdSe heterostructured nanocrystals (HNCs) that preserve their specific overall shape, whereas the PbSe core is strongly faceted with dominance of {111} facets. Hence, cation exchange proceeds while the Se anion lattice is preserved, and well-defined {111}/{111} PbSe/CdSe interfaces develop. Interestingly, by quenching the reaction at different stages of the cation exchange new structures have been isolated, such as coreshell nanorods, CdSe rods that contain one or two separated PbSe dots and fully zinc blende CdSe nanorods. The crystallographically anisotropic cation exchange has been characterized by a combined HRTEM/HAADF-STEM study of heterointerface evolution over reaction time and temperature. Strikingly, Pb and Cd are only intermixed at the PbSe/CdSe interface. We propose a plausible model for the cation exchange based on a layer-by-layer replacement of Pb2+ by Cd2+ enabled by a vacancy-assisted cation migration mechanism. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000299367500008 |
Publication Date |
2011-11-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
136 |
Open Access |
|
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
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| |
Call Number |
UA @ lucian @ c:irua:94211 |
Serial |
124 |
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| Permanent link to this record |
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Author |
Abakumov, A.M.; Batuk, D.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Tsirlin, A.A.; Niermann, D.; Waschowski, F.; Hemberger, J.; Van Tendeloo, G.; Antipov, E.V. |
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| |
Title |
Antiferroelectric (Pb,Bi)1-xFe1+xO3-y perovskites modulated by crystallographic shear planes |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
23 |
Issue |
2 |
Pages |
255-265 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
We demonstrate for the first time a possibility to vary the anion content in perovskites over a wide range through a long-range-ordered arrangement of crystallographic shear (CS) planes. Anion-deficient perovskites (Pb,Bi)1−xFe1+xO3−y with incommensurately modulated structures were prepared as single phases in the compositional range from Pb0.857Bi0.094Fe1.049O2.572 to Pb0.409Bi0.567Fe1.025O2.796. Using a combination of electron diffraction and high-resolution scanning transmission electron microscopy, we constructed a superspace model describing a periodic arrangement of the CS planes. The model was verified by refinement of the Pb0.64Bi0.32Fe1.04O2.675 crystal structure from neutron powder diffraction data ((3 + 1)D S.G. X2/m(α0γ), X = [1/2,1/2,1/2,1/2], a = 3.9082(1) Å, b = 3.90333(8) Å, c = 4.0900(1) Å, β = 91.936(2)°, q = 0.05013(4)a* + 0.09170(3)c* at T = 700 K, RP = 0.036, RwP = 0.048). The (Pb,Bi)1−xFe1+xO3−y structures consist of perovskite blocks separated by CS planes confined to nearly the (509)p perovskite plane. Along the CS planes, the perovskite blocks are shifted with respect to each other over the 1/2[110]p vector that transforms the corner-sharing connectivity of the FeO6 octahedra in the perovskite framework to an edge-sharing connectivity of the FeO5 pyramids at the CS plane, thus reducing the oxygen content. Variation of the chemical composition in the (Pb,Bi)1−xFe1+xO3−y series occurs mainly because of a changing thickness of the perovskite block between the interfaces, that can be expressed through the components of the q vector as Pb6γ+2αBi1−7γ−αFe1+γ−αO3−3γ−α. The Pb, Bi, and Fe atoms are subjected to strong displacements occurring in antiparallel directions on both sides of the perovskite blocks, resulting in an antiferroelectric-type structure. This is corroborated by the temperature-, frequency-, and field-dependent complex permittivity measurements. Pb0.64Bi0.32Fe1.04O2.675 demonstrates a remarkably high resistivity >0.1 T Ω cm at room temperature and orders antiferromagnetically below TN = 608(10) K. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000286160800018 |
Publication Date |
2010-12-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
9.466 |
Times cited |
29 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
|
| |
Call Number |
UA @ lucian @ c:irua:88651 |
Serial |
136 |
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| Permanent link to this record |
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| |
|
Author |
Belik, A.A.; Abakumov, A.M.; Tsirlin, A.A.; Hadermann, J.; Kim, J.; Van Tendeloo, G.; Takayama-Muromachi, E. |
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Title |
Article Structure and magnetic properties of BiFe0.75Mn0.25O3 perovskite prepared at ambient and high pressure |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
23 |
Issue |
20 |
Pages |
4505-4514 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Solid solutions of BiFe1xMnxO3 (0.0 ≤ x ≤ 0.4) were prepared at ambient pressure and at 6 GPa. The ambient-pressure (AP) phases crystallize in space group R3c similarly to BiFeO3. The high-pressure (HP) phases crystallize in space group R3c for x = 0.05 and in space group Pnma for 0.15 ≤ x ≤ 0.4. The structure of HP-BiFe0.75Mn0.25O3 was investigated using synchrotron X-ray powder diffraction, electron diffraction, and transmission electron microscopy. HP-BiFe0.75Mn0.25O3 has a PbZrO3-related √2ap × 4ap × 2√2ap (ap is the parameter of the cubic perovskite subcell) superstructure with a = 5.60125(9) Å, b = 15.6610(2) Å, and c = 11.2515(2) Å similar to that of Bi0.82La0.18FeO3. A remarkable feature of this structure is the unconventional octahedral tilt system, with the primary ab0a tilt superimposed on pairwise clockwise and counterclockwise rotations around the b-axis according to the oioi sequence (o stands for out-of-phase tilt, and i stands for in-phase tilt). The (FeMn)O6 octahedra are distorted, with one longer metaloxygen bond (2.222.23 Å) that can be attributed to a compensation for covalent BiO bonding. Such bonding results in the localization of the lone electron pair on Bi3+ cations, as confirmed by electron localization function analysis. The relationship between HP-BiFe0.75Mn0.25O3 and antiferroelectric structures of PbZrO3 and NaNbO3 is discussed. On heating in air, HP-BiFe0.75Mn0.25O3 irreversibly transforms to AP-BiFe0.75Mn0.25O3 starting from about 600 K. Both AP and HP phases undergo an antiferromagnetic ordering at TN ≈ 485 and 520 K, respectively, and develop a weak net magnetic moment at low temperatures. Additionally, ceramic samples of AP-BiFe0.75Mn0.25O3 show a peculiar phenomenon of magnetization reversal. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000295897400015 |
Publication Date |
2011-09-29 |
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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 |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
57 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
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| |
Call Number |
UA @ lucian @ c:irua:93581 |
Serial |
151 |
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| Permanent link to this record |
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Author |
Turner, S.; Verbeeck, J.; Ramezanipour, F.; Greedan, J.E.; Van Tendeloo, G.; Botton, G.A. |
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Title |
Atomic resolution coordination mapping in Ca2FeCoO5 brownmillerite by spatially resolved electron energy-loss spectroscopy |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
24 |
Issue |
10 |
Pages |
1904-1909 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Using a combination of high-angle annular dark field scanning transmission electron microscopy and atomically resolved electron energy-loss spectroscopy at high energy resolution in an aberration-corrected electron microscope, we demonstrate the capability of coordination mapping in complex oxides. Brownmillerite compound Ca2FeCoO5, consisting of repetitive octahedral and tetrahedral coordination layers with Fe and Co in a fixed 3+ valency, is selected to demonstrate the principle of atomic resolution coordination mapping. Analysis of the Co-L2,3 and the Fe-L2,3 edges shows small variations in the fine structure that can be specifically attributed to Co/Fe in tetrahedral or in octahedral coordination. Using internal reference spectra, we show that the coordination of the Fe and Co atoms in the compound can be mapped at atomic resolution. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000304237500024 |
Publication Date |
2012-04-25 |
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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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
33 |
Open Access |
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Notes |
A.M. Abakumov is thanked for fruitful discussions. S.T. gratefully acknowledges the Fund for Scientific Research Flanders (FWO). J.E.G. and GAB. acknowledge the support of the NSERC of Canada through Discovery Grants. The Canadian Centre for Electron Microscopy is a National Facility supported by NSERC and McMaster University and was funded by the Canada Foundation for Innovation and the Ontario Government. Part of this work was supported by funding from the European Research Council under the FP7, ERC Grant N 246791 COUNTATOMS and ERC Starting Grant N 278510 VORTEX. The EMAT microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_; |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
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| |
Call Number |
UA @ lucian @ c:irua:98379UA @ admin @ c:irua:98379 |
Serial |
175 |
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| Permanent link to this record |
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Author |
Esken, D.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Fischer, R.A. |
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Title |
Au@ZIFs: stabilization and encapsulation of cavity-size matching gold clusters inside functionalized Zeolite Imidazolate Frameworks, ZIFs |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
22 |
Issue |
23 |
Pages |
6393-6401 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The selective formation and stabilization of very small, naked metal particles inside the cavities of metal organic frameworks (MOFs) and the simultaneous realization of an even distribution of the particles throughout the crystalline MOF host matrix over a wide range of metal loading are challenging goals. MOFs reveal high specific surface areas, tunable pore sizes, and organic linkers, which are able to interact with guests. The chemically very robust zeolite imidazolate frameworks (ZIFs) are a subclass of MOFs. We chose the microporous sodalite-like ZIF-8 (Zn(MelM)(2); IM = imidazolate) and ZIF-90 (Zn(ICA)(2); ICA = imidazolate-2-carboxyaldehyde) as host matrices to influence the dispersion of imbedded gold nanoparticles (Au NPs). The metal loading was achieved via gas phase infiltration of [Au(CO)Cl] followed by a thermal hydrogenation step to form the Au NPs. Low-dose high-resolution transmission electron microscopy ((HR)TEM) and electron tomography reveal a homogeneous distribution of Au NPs throughout the ZIF matrix. The functional groups of ZIF-90 direct the anchoring of intermediate Au species and stabilize drastically smaller and quite monodisperse Au NPs in contrast to the parent not functionalized ZIF-8. The particles can be very small, match the cavity size and approach defined molecular clusters of magic numbers, i.e., Au(55), independently from the level of loading. Post-synthetic oxidation of the aldehyde groups to yield alkyl esters by the adjacent, catalytically active metal NPs is presented as a new concept of encapsulating nanoparticles inside MOFs and allows multiple steps of metal loadings without decomposition of the MOF. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000284975100025 |
Publication Date |
2010-11-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
9.466 |
Times cited |
194 |
Open Access |
|
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
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| |
Call Number |
UA @ lucian @ c:irua:95530 |
Serial |
208 |
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| Permanent link to this record |
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Author |
Barnabé, A.; Millange, F.; Maignan, A.; Hervieu, M.; Raveau, B.; Van Tendeloo, G.; Laffez, P. |
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Title |
Barium-based manganites Ln1-xBaxMnO3 with Ln = {Pr, La}: phase transitions and magnetoresistance properties |
Type |
A1 Journal article |
| |
Year |
1998 |
Publication |
Chem. mater. |
Abbreviated Journal |
Chem Mater |
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Volume |
10 |
Issue |
|
Pages |
252-259 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000071624400037 |
Publication Date |
2002-07-26 |
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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 |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
48 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 9.466; 1998 IF: 3.359 |
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Call Number |
UA @ lucian @ c:irua:25689 |
Serial |
220 |
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| Permanent link to this record |
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Author |
Li, Y.; Yang, X.-Y.; Tian, G.; Vantomme, A.; Yu, J.; Van Tendeloo, G.; Su, B.-L. |
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Title |
Chemistry of trimethyl aluminum: a spontaneous route to thermally stable 3D crystalline macroporous alumina foams with a hierarchy of pore sizes |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
22 |
Issue |
10 |
Pages |
3251-3258 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A simple and spontaneous one-pot self-formation procedure that is easy to scale up has been developed based on the chemistry of trimethylaluminum (TMA), leading to thermally stable macroporous crystalline alumina with a very unique and unprecedented three-dimensional (3D) hierarchical pore structure consisting of well-defined wormlike mesopores. TMA is the precursor of both product and porogene (viz, two working functions within the same molecule (2 in 1)). The materials obtained have been intensively characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), N2 adsorption−desorption, and mercury porosimetry. The open cagelike macrocavities are self-constructed by mesoporous nanorods (diameter of ca. 40−70 nm), which are themselves formed by a random assembly of fibrous nanoparticles 5−6 nm in size. Optical microscopy (OM) has been used in situ to follow the synthesis procedure, which led to the proposal of the formation mechanism. Methane molecules as porogens, which were instantaneously released because of the fast hydrolysis of the chemical precursor, were the key factor in producing these 3D structures with uniform co-continuous macropores that interconnected directly with the wormlike mesopores. The important characteristic of this procedure is the concurrent formation of a multiscaled porous network. The material exhibits great thermal stability. The hierarchically mesoporous−macroporous Al2O3 obtained is quite attractive for a myriad of applications, from catalysis to biomedicine. The present work illustrates that the one-pot self-formation concept, based on the chemistry of alkyl metals, is a versatile method to design industrially valuable hierarchically porous materials. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000277635000030 |
Publication Date |
2010-04-27 |
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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 |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
38 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
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Call Number |
UA @ lucian @ c:irua:82760 |
Serial |
356 |
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| Permanent link to this record |
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Author |
Hadermann, J.; Abakumov, A.M.; Van Rompaey, S.; Mankevich, A.S.; Korsakov, I.E. |
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Title |
Comment on ALaMn2O6-y (A = K, Rb): novel ferromagnetic manganites exhibiting negative giant magnetoresistance |
Type |
Editorial |
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Year |
2009 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
21 |
Issue |
9 |
Pages |
2000-2001 |
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Keywords |
Editorial; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000265781000036 |
Publication Date |
2009-04-14 |
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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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
4 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 9.466; 2009 IF: 5.368 |
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| |
Call Number |
UA @ lucian @ c:irua:77055 |
Serial |
411 |
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| Permanent link to this record |
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Author |
Adamson, P.; Hadermann, J.; Smura, C.F.; Rutt, O.J.; Hyett, G.; Free, D.G.; Clarke, S.J. |
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Title |
Competing magnetic structures and the evolution of copper ion/vacancy ordering with composition in the manganite oxide chalcogenides Sr2MnO2Cu1.5(S1-xSex)2 |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
24 |
Issue |
14 |
Pages |
2802-2816 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The series Sr2MnO2Cu1.5(S1-xSex)(2) (0 <= x <= 1) contains mixed-valent Mn ions (Mn2+/Mn3+) in MnO2 sheets which are separated by copper-deficient antifluorite-type Cu(2-delta)Ch(2) layers with delta similar to 0.5. The compounds crystallize in the structure type first described for Sr2Mn3Sb2O2 and are described in the I4/mmm space group at ambient temperatures. Below about 250 K, ordering between Cu+ ions and tetrahedral vacancies occurs which is long-range and close to complete in the sulfide-containing end member of the series Sr2MnO2Cu1.5S2 but which occurs over shorter length scales as the selenide content increases. The superstructure is an orthorhombic 2 root 2a x root 2a x c expansion in Ibam of the room temperature cell. For x > 0.3 there are no superstructure reflections evident in the X-ray or neutron diffraction patterns, and the I4/mmm description is valid for the average structure at all temperatures. However, in the pure selenide end member, Sr2MnO2Cu1.5Se2, diffuse scattering in electron diffractograms and modulation in high resolution lattice image profiles may arise from short-range Cu/vacancy order. All members of the series exhibit long-range magnetic order. In the sulfide-rich end member and in compounds with x < 0.1 in the formula Sr2MnO2Cu1.5(S1-xSex)(2), which show well developed superstructures due to long-range Cu/vacancy order, the magnetic structure has a (1/4 1/4 0) propagation vector in which ferromagnetic zigzag chains of Mn moments in the MnO2 sheets are coupled antiferromagnetically in an arrangement described as the CE-type magnetic structure and found in many mixed-valent perovskite and Ruddlesden-Popper type oxide manganites. In these cases the magnetic cell is an a x 2b x c expansion of the low temperature Ibam structural cell. For x >= 0.2 in the formula Sr2MnO2Cu1.5(S1-xSex)(2) the magnetic structure has a (0 0 0) propagation vector and is similar to the A-type structure, also commonly adopted by some perovskite-related manganites, in which the Mn moments in the MnO2 sheets are coupled ferromagnetically and long-range antiferromagnetic order results from antiferromagnetic coupling between planes. In the region of the transition between the two different structural and magnetic long-range ordering schemes (0.1 < x < 0.2) the two magnetic structures coexist in the same sample. The evolution of the competition between magnetic ordering schemes and the length scale of the structural order with composition in Sr2MnO2Cu1.5(S1-xSex)(2) suggest that the changes in magnetic and structural order are related consequences of the introduction of chemical disorder. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000306674200024 |
Publication Date |
2012-06-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
11 |
Open Access |
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|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
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| |
Call Number |
UA @ lucian @ c:irua:100839 |
Serial |
435 |
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| Permanent link to this record |
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Author |
Hadermann, J.; Abakumov, A.M.; Gillie, L.J.; Martin, C.; Hervieu, M. |
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Title |
Coupled cation and charge ordering in the CaMn306 tunnel structure |
Type |
A1 Journal article |
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Year |
2006 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
18 |
Issue |
23 |
Pages |
5530-5536 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000241808600021 |
Publication Date |
2006-10-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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 |
33 |
Open Access |
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Notes |
Iap V-1 |
Approved |
Most recent IF: 9.466; 2006 IF: 5.104 |
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Call Number |
UA @ lucian @ c:irua:61374 |
Serial |
534 |
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| Permanent link to this record |
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Author |
Morozov, V.A.; Raskina, M.V.; Lazoryak, B.I.; Meert, K.W.; Korthout, K.; Smet, P.F.; Poelman, D.; Gauquelin, N.; Verbeeck, J.; Abakumov, A.M.; Hadermann, J.; |
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Title |
Crystal Structure and Luminescent Properties of R2-xEux(MoO4)(3) (R = Gd, Sm) Red Phosphors |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
26 |
Issue |
24 |
Pages |
7124-7136 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The R-2(MoO4)(3) (R = rare earth elements) molybdates doped with Eu3+ cations are interesting red-emitting materials for display and solid-state lighting applications. The structure and luminescent properties of the R2-xEux(MoO4)(3) (R = Gd, Sm) solid solutions have been investigated as a function of chemical composition and preparation conditions. Monoclinic (alpha) and orthorhombic (beta') R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) modifications were prepared by solid-state reaction, and their structures were investigated using synchrotron powder X-ray diffraction and transmission electron microscopy. The pure orthorhombic beta'-phases could be synthesized only by quenching from high temperature to room temperature for Gd2-xEux(MoO4)(3) in the Eu3+-rich part (x > 1) and for all Sm2-xEux(MoO4)(3) solid solutions. The transformation from the alpha-phase to the beta'-phase results in a notable increase (similar to 24%) of the unit cell volume for all R2-xEux(MoO4)(3) (R = Sm, Gd) solid solutions. The luminescent properties of all R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) solid solutions were measured, and their optical properties were related to their structural properties. All R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) phosphors emit intense red light dominated by the D-5(0)-> F-7(2) transition at similar to 616 nm. However, a change in the multiplet splitting is observed when switching from the monoclinic to the orthorhombic structure, as a consequence of the change in coordination polyhedron of the luminescent ion from RO8 to RO7 for the alpha- and beta'-modification, respectively. The Gd2-xEux(MoO4)(3) solid solutions are the most efficient emitters in the range of 0 < x < 1.5, but their emission intensity is comparable to or even significantly lower than that of Sm2-xEux(MoO4)(3) for higher Eu3+ concentrations (1.5 <= x <= 1.75). Electron energy loss spectroscopy (EELS) measurements revealed the influence of the structure and element content on the number and positions of bands in the ultraviolet-visible-infrared regions of the EELS spectrum. |
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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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Language |
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Wos |
000347139700027 |
Publication Date |
2014-11-27 |
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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 |
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 |
24 |
Open Access |
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Notes |
Fwo G039211n; G004413n; 278510 Vortex ECASJO_; |
Approved |
Most recent IF: 9.466; 2014 IF: 8.354 |
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Call Number |
UA @ lucian @ c:irua:122829UA @ admin @ c:irua:122829 |
Serial |
558 |
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| Permanent link to this record |
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Author |
Bune, R.O.; Lobanov, M.V.; Popov, G.; Greenblatt, M.; Botez, C.E.; Stephens, P.W.; Croft, M.; Hadermann, J.; Van Tendeloo, G. |
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Title |
Crystal structure and properties of Ru-stoichiometric LaSrMnRuO6 |
Type |
A1 Journal article |
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Year |
2006 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
18 |
Issue |
10 |
Pages |
2611-2617 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000237593400022 |
Publication Date |
2006-05-09 |
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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 |
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 |
17 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466; 2006 IF: 5.104 |
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Call Number |
UA @ lucian @ c:irua:59441 |
Serial |
563 |
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| Permanent link to this record |
