Records |
Author |
Zhao, C.X.; Xu, W.; Li, L.L.; Zhang, C.; Peeters, F.M. |
Title |
Terahertz plasmon-polariton modes in graphene driven by electric field inside a Fabry-Perot cavity |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
117 |
Issue |
117 |
Pages |
223104 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present a theoretical study on plasmon-polariton modes in graphene placed inside an optical cavity and driven by a source-to-drain electric field. The electron velocity and electron temperature are determined by solving self-consistently the momentum-and energy-balance equations in which electron interactions with impurities, acoustic-, and optic-phonons are included. Based on many-body self-consistent field theory, we develop a tractable approach to study plasmon-polariton in an electron gas system. We find that when graphene is placed inside a Fabry-Perot cavity, two branches of the plasmon-polariton modes can be observed and these modes are very much optic-or plasmon-like. The frequencies of these modes depend markedly on driving electric field especially at higher resonant frequency regime. Moreover, the plasmon-polariton frequency in graphene is in terahertz (THz) bandwidth and can be tuned by changing the cavity length, gate voltage, and driving electric field. This work is pertinent to the application of graphene-based structures as tunable THz plasmonic devices. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000356176100004 |
Publication Date |
2015-06-10 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
13 |
Open Access |
|
Notes |
; This work was supported by the Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. F.M.P. was a specially appointed Professor for foreign expert at the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:127076 |
Serial |
3507 |
Permanent link to this record |
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|
|
Author |
Li, L.L.; Xu, W.; Peeters, F.M. |
Title |
Optical conductivity of topological insulator thin films |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
117 |
Issue |
117 |
Pages |
175305 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present a detailed theoretical study on the optoelectronic properties of topological insulator thin film (TITFs). The k . p approach is employed to calculate the energy spectra and wave functions for both the bulk and surface states in the TITF. With these obtained results, the optical conductivities induced by different electronic transitions among the bulk and surface states are evaluated using the energy-balance equation derived from the Boltzmann equation. We find that for Bi2Se3-based TITFs, three characteristic regimes for the optical absorption can be observed. (i) In the low radiation frequency regime (photon energy (h) over bar omega < 200 meV), the free-carrier absorption takes place due to intraband electronic transitions. An optical absorption window can be observed. (ii) In the intermediate radiation frequency regime (200 < (h) over bar omega < 300 meV), the optical absorption is induced mainly by interband electronic transitions from surface states in the valance band to surface states in the conduction band and an universal value sigma(0) = e(2) / (8<(h)over bar>) for the optical conductivity can be obtained. (iii) In the high radiation frequency regime ((h) over bar omega > 300 meV), the optical absorption can be achieved via interband electronic transitions from bulk and surface states in the valance band to bulk and surface states in the conduction band. A strong absorption peak can be observed. These interesting findings indicate that optical measurements can be applied to identify the energy regimes of bulk and surface states in the TITF. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000354984100615 |
Publication Date |
2015-05-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
9 |
Open Access |
|
Notes |
; This work was supported by the National Natural Science Foundation of China (Grant No. 11304316), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:126412 |
Serial |
2473 |
Permanent link to this record |
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Author |
Li, L.; Nijs, I.; De Boeck, H.; Vinduskova, O.; Reynaert, S.; Donnelly, C.; Zi, L.; Verbruggen, E. |
Title |
Longer dry and wet spells alter the stochasticity of microbial community assembly in grassland soils |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Soil biology and biochemistry |
Abbreviated Journal |
|
Volume |
178 |
Issue |
|
Pages |
108969-9 |
Keywords |
A1 Journal article; ADReM Data Lab (ADReM); Integrated Molecular Plant Physiology Research (IMPRES); Plant and Ecosystems (PLECO) – Ecology in a time of change |
Abstract |
Climate change is increasing the duration of alternating wet and dry spells. These fluctuations affect soil water availability and other soil properties which are crucial drivers of soil microbial communities. While soil microbial communities have a moderate capacity to recover once a drought ceases, the expected alternation of strongly opposing regimes can challenge their capacity to adapt. Here, we set up experimental grassland mesocosms where precipitation frequency was adjusted along a gradient while holding total precipitation constant. The gradient varied the duration of wet and dry spells from 1 to 60 days during a total of 120 days, where we hy-pothesized that especially intermediate durations would increase the importance of stochastic community as-sembly due to frequent alternation of opposing environmental regimes. We examined bacterial and fungal community composition, diversity, co-occurrence patterns and assembly mechanisms across these different precipitation treatments. Our results show that 1) intermediate regimes of wet and dry spells increased the stochasticity of microbial community assembly whereas microbial communities at low and high regimes were subjected to more deterministic assembly, and 2) more persistent precipitation regimes (>6 days duration) reduced the fungal diversity and network connectivity but had little effect on bacterial communities. Collec-tively, these findings indicate that longer alternating wet and dry events lead to a less predictable and connected soil microbial community. This study provides new insight into the likely mechanisms through which precipi-tation persistence alters soil microbial communities and their predictability. |
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 |
000930582500001 |
Publication Date |
2023-01-28 |
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 |
0038-0717 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:195257 |
Serial |
9211 |
Permanent link to this record |
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Author |
Li, L.; Kong, X.; Peeters, F.M. |
Title |
New nanoporous graphyne monolayer as nodal line semimetal : double Dirac points with an ultrahigh Fermi velocity |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
141 |
Issue |
141 |
Pages |
712-718 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Two-dimensional (2D) carbon materials play an important role in nanomaterials. We propose a new carbon monolayer, named hexagonal-4,4,4-graphyne (H-4,H-4,H-4-graphyne), which is a nanoporous structure composed of rectangular carbon rings and triple bonds of carbon. Using first-principles calculations, we systematically studied the structure, stability, and band structure of this new material. We found that its total energy is lower than that of experimentally synthesized beta-graphdiyne and it is stable at least up to 1500 K. In contrast to the single Dirac point band structure of other 2D carbon monolayers, the band structure of H-4,H-4,H-4-graphyne exhibits double Dirac points along the high-symmetry points and the corresponding Fermi velocities (1.04-1.27 x 10(6) m/s) are asymmetric and higher than that of graphene. The origin of these double Dirac points is traced back to the nodal line states, which can be well explained by a tight-binding model. The H-4,H-4,H-4-graphyne forms a moire superstructure when placed on top of a hexagonal boron nitride substrate. These properties make H-4,H-4,H-4-graphyne a promising semimetal material for applications in high-speed electronic devices. (C) 2018 Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000450312600072 |
Publication Date |
2018-10-01 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
38 |
Open Access |
|
Notes |
; This work was supported by the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl), and the FLAG-ERA project TRANS2DTMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government -department EWI. ; |
Approved |
Most recent IF: 6.337 |
Call Number |
UA @ admin @ c:irua:155364 |
Serial |
5222 |
Permanent link to this record |
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|
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Author |
Li, L.; Kong, X.; Leenaerts, O.; Chen, X.; Sanyal, B.; Peeters, F.M. |
Title |
Carbon-rich carbon nitride monolayers with Dirac cones : Dumbbell C4N |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
118 |
Issue |
118 |
Pages |
285-290 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Two-dimensional (2D) carbon nitride materials play an important role in energy-harvesting, energy-storage and environmental applications. Recently, a new carbon nitride, 2D polyaniline (C3N) was proposed [PNAS 113 (2016) 7414-7419]. Based on the structure model of this C3N monolayer, we propose two new carbon nitride monolayers, named dumbbell (DB) C4N-I and C4N-II. Using first-principles calculations, we systematically study the structure, stability, and band structure of these two materials. In contrast to other carbon nitride monolayers, the orbital hybridization of the C/N atoms in the DB C4N monolayers is sp(3). Remarkably, the band structures of the two DB C4N monolayers have a Dirac cone at the K point and their Fermi velocities (2.6/2.4 x 10(5) m/s) are comparable to that of graphene. This makes them promising materials for applications in high-speed electronic devices. Using a tight-binding model, we explain the origin of the Dirac cone. (C) 2017 Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000401120800033 |
Publication Date |
2017-03-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
36 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.337 |
Call Number |
UA @ lucian @ c:irua:143726 |
Serial |
4588 |
Permanent link to this record |
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Author |
Li, H.; Zhang, L.; Li, L.; Wu, C.; Huo, Y.; Chen, Y.; Liu, X.; Ke, X.; Luo, J.; Van Tendeloo, G. |
Title |
Two-in-one solution using insect wings to produce graphene-graphite films for efficient electrocatalysis |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Nano Research |
Abbreviated Journal |
Nano Res |
Volume |
12 |
Issue |
1 |
Pages |
33-39 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Natural organisms contain rich elements and naturally optimized smart structures, both of which have inspired various innovative concepts and designs in human society. In particular, several natural organisms have been used as element sources to synthesize low-cost and environmentally friendly electrocatalysts for the oxygen reduction reaction (ORR) in fuel cells and metal-air batteries, which are clean energy devices. However, to date, no naturally optimized smart structures have been employed in the synthesis of ORR catalysts, including graphene-based materials. Here, we demonstrate a novel strategy to synthesize graphene-graphite films (GGFs) by heating butterfly wings coated with FeCl3 in N-2, in which the full power of natural organisms is utilized. The wings work not only as an element source for GGF generation but also as a porous supporting structure for effective nitrogen doping, two-dimensional spreading, and double-face exposure of the GGFs. These GGFs exhibit a half-wave potential of 0.942 V and a H2O2 yield of < 0.07% for ORR electrocatalysis; these values are comparable to those for the best commercial Pt/C and all previously reported ORR catalysts in alkaline media. This two-in-one strategy is also successful with cicada and dragonfly wings, indicating that it is a universal, green, and cost-effective method for developing high-performance graphene-based materials. |
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 |
000453629900004 |
Publication Date |
2018-08-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1998-0124 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.354 |
Times cited |
7 |
Open Access |
Not_Open_Access |
Notes |
; The authors would like to thank Drs Qiang Wang and Wenjuan Yuan for useful discussions. This work was financially supported by the National Key R&D Program of China (No. 2017YFA0700104), the National Natural Science Foundation of China (Nos. 21601136 and 11404016), the National Program for Thousand Young Talents of China, Tianjin Municipal Education Commission, Tianjin Municipal Science and Technology Commission (No. 15JCYBJC52600), and the Fundamental Research Fund of Tianjin University of Technology. This work also made use of the resources of the National Center for Electron Microscopy in Beijing. ; |
Approved |
Most recent IF: 7.354 |
Call Number |
UA @ admin @ c:irua:156210 |
Serial |
5265 |
Permanent link to this record |
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Author |
Li, L.; Leenaerts, O.; Kong, X.; Chen, X.; Zhao, M.; Peeters, F.M. |
Title |
Gallium bismuth halide GaBi-X2 (X = I, Br, Cl) monolayers with distorted hexagonal framework: Novel room-temperature quantum spin Hall insulators |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nano Research |
Abbreviated Journal |
Nano Res |
Volume |
10 |
Issue |
10 |
Pages |
2168-2180 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Quantum spin Hall (QSH) insulators with a large topologically nontrivial bulk gap are crucial for future applications of the QSH effect. Among these, group III-V monolayers and their halides, which have a chair structure (regular hexagonal framework), have been widely studied. Using first-principles calculations, we formulate a new structure model for the functionalized group III-V monolayers, which consist of rectangular GaBi-X-2 (X = I, Br, Cl) monolayers with a distorted hexagonal framework (DHF). These structures have a far lower energy than the GaBi-X-2 monolayers with a chair structure. Remarkably, the DHF GaBi-X-2 monolayers are all QSH insulators, which exhibit sizeable nontrivial band gaps ranging from 0.17 to 0.39 eV. The band gaps can be widely tuned by applying different spin-orbit coupling strengths, resulting in a distorted Dirac cone. |
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 |
000401320700029 |
Publication Date |
2017-04-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1998-0124 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.354 |
Times cited |
15 |
Open Access |
|
Notes |
; This work was supported by the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 7.354 |
Call Number |
UA @ lucian @ c:irua:143739 |
Serial |
4598 |
Permanent link to this record |
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Author |
Bugani, S.; Modugno, F.; Lucejko, J.J.; Giachi, G.; Cagno, S.; Cloetens, P.; Janssens, K.; Morselli, L. |
Title |
Study on the impregnation of archaeological waterlogged wood with consolidation treatments using synchrotron radiation microtomography |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
Volume |
395 |
Issue |
7 |
Pages |
1977-1985 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In favourable conditions of low temperature and low oxygen concentration, archaeological waterlogged wooden artefacts, such as shipwrecks, can survive with a good state of preservation. Nevertheless, anaerobic bacteria can considerably degrade waterlogged wooden objects with a significant loss in polysaccharidic components. Due to these decay processes, wood porosity and water content increase under ageing. In such conditions, the conservation treatments of archaeological wooden artefacts often involve the replacement of water with substances which fill the cavities and help to prevent collapse and stress during drying. The treatments are very often expensive and technically difficult, and their effectiveness very much depends on the chemical and physical characteristics of the substances used for impregnation. Also important are the degree of cavity-filling, penetration depth and distribution in the structure of the wood. In this study, the distribution in wood cavities of some mixtures based on polyethylene glycols and colophony, used for the conservation of waterlogged archaeological wood, was investigated using synchrotron radiation X-ray computed microtomography (SR-A mu CT). This non-destructive imaging technique was useful for the study of the degraded waterlogged wood and enabled us to visualise the morphology of the wood and the distribution of the materials used in the wood treatments. The study has shown how deposition is strictly related to the dimension of the wooden cavities. The work is currently proceeding with the comparison of synchrotron observations with the data of the solutions viscosity and with those of the properties imparted to the wood by the treatments. |
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 |
000272017000005 |
Publication Date |
2009-09-16 |
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 |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.431 |
Times cited |
30 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.431; 2009 IF: 3.480 |
Call Number |
UA @ admin @ c:irua:94493 |
Serial |
5853 |
Permanent link to this record |
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Author |
Bugani, S.; Camaiti, M.; Morselli, L.; Van de Casteele, E.; Janssens, K. |
Title |
Investigating morphological changes in treated vs. untreated stone building materials by x-ray micro-CT |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
Volume |
391 |
Issue |
4 |
Pages |
1343-1350 |
Keywords |
A1 Journal article; Vision lab; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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 |
000256088700030 |
Publication Date |
2008-03-14 |
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 |
|
ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.431 |
Times cited |
25 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.431; 2008 IF: 3.328 |
Call Number |
UA @ admin @ c:irua:69319 |
Serial |
5673 |
Permanent link to this record |
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Author |
Bugani, S.; Camaiti, M.; Morselli, L.; Van de Casteele, E.; Janssens, K. |
Title |
Investigation on porosity changes of Lecce stone due to conservation treatments by means of x-ray nano- and improved micro-computed tomography: preliminary results |
Type |
A1 Journal article |
Year |
2007 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
X-Ray Spectrom |
Volume |
36 |
Issue |
5 |
Pages |
316-320 |
Keywords |
A1 Journal article; Vision lab; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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 |
000249961800005 |
Publication Date |
2007-07-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.298 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.298; 2007 IF: 1.117 |
Call Number |
UA @ admin @ c:irua:66602 |
Serial |
5676 |
Permanent link to this record |
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Author |
Li, L.; Liao, Z.; Gauquelin, N.; Minh Duc Nguyen; Hueting, R.J.E.; Gravesteijn, D.J.; Lobato, I.; Houwman, E.P.; Lazar, S.; Verbeeck, J.; Koster, G.; Rijnders, G. |
Title |
Epitaxial stress-free growth of high crystallinity ferroelectric PbZr0.52Ti0.48O3 on GaN/AlGaN/Si(111) substrate |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
Volume |
5 |
Issue |
2 |
Pages |
1700921 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
<script type='text/javascript'>document.write(unpmarked('Due to its physical properties gallium-nitride (GaN) is gaining a lot of attention as an emerging semiconductor material in the field of high-power and high-frequency electronics applications. Therefore, the improvement in the performance and/or perhaps even extension in functionality of GaN based devices would be highly desirable. The integration of ferroelectric materials such as lead-zirconate-titanate (PbZrxTi1-xO3) with GaN has a strong potential to offer such an improvement. However, the large lattice mismatch between PZT and GaN makes the epitaxial growth of Pb(Zr1-xTix)O-3 on GaN a formidable challenge. This work discusses a novel strain relaxation mechanism observed when MgO is used as a buffer layer, with thicknesses down to a single unit cell, inducing epitaxial growth of high crystallinity Pb(Zr0.52Ti0.48)O-3 (PZT) thin films. The epitaxial PZT films exhibit good ferroelectric properties, showing great promise for future GaN device applications.')); |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000423173800005 |
Publication Date |
2017-11-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2196-7350 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.279 |
Times cited |
15 |
Open Access |
Not_Open_Access |
Notes |
; L.L., Z.L.L., and N.G. contributed equally to this work. L.L. acknowledges financial support from Nano Next NL (Grant no. 7B 04). The authors acknowledge NXP for providing the GaN/AlGaN/Si (111) wafer. N.G. acknowledges funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and J.V. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) project 42/FA070100/6088 “nieuwe eigenschappen in complexe Oxides.” N.G. acknowledges the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280432) which partly funded this study. ; |
Approved |
Most recent IF: 4.279 |
Call Number |
UA @ lucian @ c:irua:148427UA @ admin @ c:irua:148427 |
Serial |
4872 |
Permanent link to this record |
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Author |
Xu, H.; Li, H.; Gauquelin, N.; Chen, X.; Wu, W.-F.; Zhao, Y.; Si, L.; Tian, D.; Li, L.; Gan, Y.; Qi, S.; Li, M.; Hu, F.; Sun, J.; Jannis, D.; Yu, P.; Chen, G.; Zhong, Z.; Radovic, M.; Verbeeck, J.; Chen, Y.; Shen, B. |
Title |
Giant tunability of Rashba splitting at cation-exchanged polar oxide interfaces by selective orbital hybridization |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Advanced materials |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The 2D electron gas (2DEG) at oxide interfaces exhibits extraordinary properties, such as 2D superconductivity and ferromagnetism, coupled to strongly correlated electrons in narrow d-bands. In particular, 2DEGs in KTaO3 (KTO) with 5d t2g orbitals exhibit larger atomic spin-orbit coupling and crystal-facet-dependent superconductivity absent for 3d 2DEGs in SrTiO3 (STO). Herein, by tracing the interfacial chemistry, weak anti-localization magneto-transport behavior, and electronic structures of (001), (110), and (111) KTO 2DEGs, unambiguously cation exchange across KTO interfaces is discovered. Therefore, the origin of the 2DEGs at KTO-based interfaces is dramatically different from the electronic reconstruction observed at STO interfaces. More importantly, as the interface polarization grows with the higher order planes in the KTO case, the Rashba spin splitting becomes maximal for the superconducting (111) interfaces approximately twice that of the (001) interface. The larger Rashba spin splitting couples strongly to the asymmetric chiral texture of the orbital angular moment, and results mainly from the enhanced inter-orbital hopping of the t2g bands and more localized wave functions. This finding has profound implications for the search for topological superconductors, as well as the realization of efficient spin-charge interconversion for low-power spin-orbitronics based on (110) and (111) KTO interfaces. An unambiguous cation exchange is discovered across the interfaces of (001), (110), and (111) KTaO3 2D electron gases fabricated at room temperature. Remarkably, the (111) interfaces with the highest superconducting transition temperature also turn out to show the strongest electron-phonon interaction and the largest Rashba spin splitting. image |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
001219658400001 |
Publication Date |
2024-03-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:206037 |
Serial |
9152 |
Permanent link to this record |
|
|
|
Author |
Yang, C.-Q.; Zhi, R.; Rothmann, M.U.; Xu, Y.-Y.; Li, L.-Q.; Hu, Z.-Y.; Pang, S.; Cheng, Y.-B.; Van Tendeloo, G.; Li, W. |
Title |
Unveiling the intrinsic structure and intragrain defects of organic-inorganic hybrid perovskites by ultralow dose transmission electron microscopy |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Advanced materials |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
1-9 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Transmission electron microscopy (TEM) is a powerful tool for unveiling the structural, compositional, and electronic properties of organic-inorganic hybrid perovskites (OIHPs) at the atomic to micrometer length scales. However, the structural and compositional instability of OIHPs under electron beam radiation results in misunderstandings of the microscopic structure-property-performance relationship in OIHP devices. Here, ultralow dose TEM is utilized to identify the mechanism of the electron-beam-induced changes in OHIPs and clarify the cumulative electron dose thresholds (critical dose) of different commercially interesting state-of-the-art OIHPs, including methylammonium lead iodide (MAPbI(3)), formamidinium lead iodide (FAPbI(3)), FA(0.83)Cs(0.17)PbI(3), FA(0.15)Cs(0.85)PbI(3), and MAPb(0.5)Sn(0.5)I(3). The critical dose is related to the composition of the OIHPs, with FA(0.15)Cs(0.85)PbI(3) having the highest critical dose of approximate to 84 e angstrom(-2) and FA(0.83)Cs(0.17)PbI(3) having the lowest critical dose of approximate to 4.2 e angstrom(-2). The electron beam irradiation results in the formation of a superstructure with ordered I and FA vacancies along (c), as identified from the three major crystal axes in cubic FAPbI(3), (c), (c), and (c). The intragrain planar defects in FAPbI(3) are stable, while an obvious modification is observed in FA(0.83)Cs(0.17)PbI(3) under continuous electron beam exposure. This information can serve as a guide for ensuring a reliable understanding of the microstructure of OIHP optoelectronic devices by TEM. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000950461600001 |
Publication Date |
2023-02-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
29.4 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 29.4; 2023 IF: 19.791 |
Call Number |
UA @ admin @ c:irua:195116 |
Serial |
7349 |
Permanent link to this record |
|
|
|
Author |
Wang, F.; Gao, T.; Zhang, Q.; Hu, Z.-Y.; Jin, B.; Li, L.; Zhou, X.; Li, H.; Van Tendeloo, G.; Zhai, T. |
Title |
Liquid-alloy-assisted growth of 2D ternaryGa2In4S9 toward high-performance UV photodetection |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
31 |
Issue |
2 |
Pages |
1806306 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
2D ternary systems provide another degree of freedom of tuning physical properties through stoichiometry variation. However, the controllable growth of 2D ternary materials remains a huge challenge that hinders their practical applications. Here, for the first time, by using a gallium/indium liquid alloy as the precursor, the synthesis of high-quality 2D ternary Ga2In4S9 flakes of only a few atomic layers thick (approximate to 2.4 nm for the thinnest samples) through chemical vapor deposition is realized. Their UV-light-sensing applications are explored systematically. Photodetectors based on the Ga2In4S9 flakes display outstanding UV detection ability (R-lambda = 111.9 A W-1, external quantum efficiency = 3.85 x 10(4)%, and D* = 2.25 x 10(11) Jones@360 nm) with a fast response speed (tau(ring) approximate to 40 ms and tau(decay) approximate to 50 ms). In addition, Ga2In4S9-based phototransistors exhibit a responsivity of approximate to 10(4) A W-1@360 nm above the critical back-gate bias of approximate to 0 V. The use of the liquid alloy for synthesizing ultrathin 2D Ga2In4S9 nanostructures may offer great opportunities for designing novel 2D optoelectronic materials to achieve optimal device performance. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000455111100013 |
Publication Date |
2018-11-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
29 |
Open Access |
Not_Open_Access |
Notes |
; F.K.W., T.G, and Q.Z. contributed equally to this work. The authors acknowledge the support from National Nature Science Foundation of China (21825103, 51727809, 51472097, 91622117, and 51872069), National Basic Research Program of China (2015CB932600), and the Fundamental Research Funds for the Central Universities (2017KFKJXX007, 2015ZDTD038, 2017III055, and 2018III039GX). The authors thank the Analytical and Testing Centre of Huazhong University of Science and Technology. ; |
Approved |
Most recent IF: 19.791 |
Call Number |
UA @ admin @ c:irua:156756 |
Serial |
5254 |
Permanent link to this record |
|
|
|
Author |
Liao, Z.; Gauquelin, N.; Green, R.J.; Macke, S.; Gonnissen, J.; Thomas, S.; Zhong, Z.; Li, L.; Si, L.; Van Aert, S.; Hansmann, P.; Held, K.; Xia, J.; Verbeeck, J.; Van Tendeloo, G.; Sawatzky, G.A.; Koster, G.; Huijben, M.; Rijnders, G. |
Title |
Thickness dependent properties in oxide heterostructures driven by structurally induced metal-oxygen hybridization variations |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
27 |
Issue |
17 |
Pages |
1606717 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Thickness-driven electronic phase transitions are broadly observed in different types of functional perovskite heterostructures. However, uncertainty remains whether these effects are solely due to spatial confinement, broken symmetry, or rather to a change of structure with varying film thickness. Here, this study presents direct evidence for the relaxation of oxygen-2p and Mn-3d orbital (p-d) hybridization coupled to the layer-dependent octahedral tilts within a La2/3Sr1/3MnO3 film driven by interfacial octahedral coupling. An enhanced Curie temperature is achieved by reducing the octahedral tilting via interface structure engineering. Atomically resolved lattice, electronic, and magnetic structures together with X-ray absorption spectroscopy demonstrate the central role of thickness-dependent p-d hybridization in the widely observed dimensionality effects present in correlated oxide heterostructures. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000400449200011 |
Publication Date |
2017-03-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
55 |
Open Access |
|
Notes |
M.H., G.K., and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) Grant No. NMP3-LA-2010-246102 IFOX. J.V. and S.V.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (Grant Nos. G.0044.13N, G.0374.13N, G.0368.15N, and G.0369.15N). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX. N.G., J.G., S.V.A., and J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which was funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. |
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ admin @ c:irua:152640 |
Serial |
5367 |
Permanent link to this record |
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|
|
Author |
Basile, F.; Benito, P.; Bugani, S.; de Nolf, W.; Fornasari, G.; Janssens, K.; Morselli, L.; Scavetta, E.; Tonelli, D.; Vaccari, A. |
Title |
Combined use of synchrotron-radiation-based imaging techniques for the characterization of structured catalysts |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
20 |
Issue |
23 |
Pages |
4117-4126 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Active-phase-coated metallic supports as structured catalysts are gaining attention in endothermic and exothermic processes because they improve heat transfer. The deposition of a well-adhered and stable catalyst layer on the metallic support constitutes an important feature for the successful application of the final material. In this work, coating of FeCrAlY foams is performed by a one-step electrosynthesis-deposition of hydrotalcite-type compounds, precursors of catalysts active in endothermic steam methane reforming. The catalysts are studied at different length scales by using, for the first time, a combination of several techniques: SEM/EDS and X-ray fluorescence, X-ray powder diffraction and absorption-tomography experiments on the micro- and nanoscales at a synchrotron facility. The results show that the morphology of the coating depends on the synthesis conditions and that the catalyst may be described as Ni metal crystallites dispersed on γ-Al2O3, homogeneously coating the FeCrAlY foam. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000285392900010 |
Publication Date |
2010-09-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
24 |
Open Access |
|
Notes |
; The authors give thanks to Dr. Cloetens, for helping during the absorption tomography experiments, performed at ID19 of the ESRF; and P. Blauet and R. Toucolou, for helping during the mu-XRF/XRPD and nano-XRF experiments at ID22 and ID22-NI of the ESRF. The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, Italy) is gratefully acknowledged. ; |
Approved |
Most recent IF: 12.124; 2010 IF: 8.508 |
Call Number |
UA @ admin @ c:irua:85834 |
Serial |
5525 |
Permanent link to this record |
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|
|
Author |
Cole, B.E.; Batty, W.; Singleton, J.; Chamberlain, J.M.; Li, L.; van Bockstal, L.; Imanaka, Y.; Shimamoto, Y.; Miura, N.; Peeters, F.M.; Henini, M.; Cheng, T. |
Title |
Collective cyclotron modes in high mobility two-dimensional hole systems in GaAs-(Ga,Al)As heterojunctions: 2: experiments at magnetic fields of up to forty Tesla |
Type |
A1 Journal article |
Year |
1997 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
9 |
Issue |
|
Pages |
4887-4896 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
A1997XE20300012 |
Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 1997 IF: 1.479 |
Call Number |
UA @ lucian @ c:irua:19292 |
Serial |
385 |
Permanent link to this record |
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|
|
Author |
Li, L. |
Title |
Untangling microbial community assembly in rainforest and grassland soils under increasing precipitation persistence |
Type |
Doctoral thesis |
Year |
2023 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
179 p. |
Keywords |
Doctoral thesis; Integrated Molecular Plant Physiology Research (IMPRES); Plant and Ecosystems (PLECO) – Ecology in a time of change |
Abstract |
Climate change is causing alterations in precipitation patterns, leading to adverse ecological consequences in many ecosystems. Recently, an increasingly persistent weather pattern has emerged, characterized by lengthening the duration of alternating dry and wet periods, which is more complex than exclusively drought or increasing precipitation. It is currently unclear how soil microbial communities respond to these new regimes in relation to their interactions with plants, especially in precipitation-sensitive ecosystems, such as tropical rainforests and grasslands. In this thesis, we explored responses of soil bacterial and fungal communities to increasing weather persistence in rainforests and grasslands, using high throughput sequencing technology. We firstly investigated the resistance and resilience of microbial communities to prolonged drought in a mature seasonal tropical rainforest which experiences unusually intensive dry seasons in the current century. Through excluding rainfall during and after the dry season, a simulated prolongation of the dry season by five months was compared to the control. Our results indicate that as rain exclusion progressed, the microbial communities increasingly diverged from the control, indicating a moderate resistance to prolonged drought. However, when the drought ceased, the composition and co-occurrence patterns of soil microbial communities immediately recovered to that in the control, implying a high resilience. To further investigate the ecological roles of soil microbial communities in response to increasing weather persistence, we set up grassland mesocosm experiments. In these experiments, precipitation frequency was adjusted along a series, ranging from 1 to 60 consecutive days alternating of dry and wet periods, while keeping the total precipitation constant. Our results show that microbial community assembly tended to be more stochastic processes at intermediate persistence of dry and wet alternations while more deterministic processes dominated at low and high persistence within 120 days regime exposure. Moreover, more persistent precipitation reduced the fungal diversity and network connectivity but barely impacted that of bacterial communities. The prior experiences of persistent weather events for one year caused legacy effects. The soil microbial legacy induced by soil microbial communities subjected to prior persistent weather events was more enduring in subsequent fungal communities than bacterial communities, likely due to slower growth of fungi compared to bacteria. However, a minor effect of soil microbial legacy was observed on plant performance. In addition, we kept the grassland mesocosm experiment for two growing seasons. The effects of precipitation persistence on soil microbial communities increased in the second year. The dissimilarities of microbial communities between the first and second year were less with more persistent precipitation, potentially resulting in more vulnerable microbial communities, due to some taxa disappearing and a reduction in functional redundancy under more persistent weather. To conclude, our findings provide a comprehensive theoretical understanding of soil microbial communities in response to the current and future climate change, drawing from both natural and experimental systems. It helps in predicting and managing the impacts of future climate change on ecosystems mediated by microbial communities. Additionally, the findings of microbe-mediated legacy effects on grassland ecosystems can provide practical guidance for their application in agriculture, specifically for using an inoculum to mitigate the impacts of climate change. |
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Corporate Author |
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Publisher |
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Place of Publication |
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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 |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:198498 |
Serial |
9240 |
Permanent link to this record |