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| Author | Doğan, F.; Covaci, L.; Kim, W.; Marsiglio, F. | ||||
| Title | Emerging nonequilibrium bound state in spin-current–local-spin scattering | Type | A1 Journal article | ||
| Year | 2009 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 80 | Issue | 10 | Pages | 104434 |
| Keywords | A1 Journal article | ||||
| Abstract | Magnetization reversal is a well-studied problem with obvious applicability in computer hard drives. One can accomplish a magnetization reversal in at least one of two ways: application of a magnetic field or through a spin current. The latter is more amenable to a fully quantum-mechanical analysis. We formulate and solve the problem whereby a spin current interacts with a ferromagnetic Heisenberg spin chain, to eventually reverse the magnetization of the chain. Spin flips are accomplished through both elastic and inelastic scattering. A consequence of the inelastic-scattering channel, when it is no longer energetically possible, is the occurrence of a nonequilibrium bound state, which is an emergent property of the coupled local plus itinerant spin system. For certain definite parameter values the itinerant spin lingers near the local spins for some time, before eventually leaking out as an outwardly diffusing state. This phenomenon results in spin-flip dynamics and filtering properties for this type of system. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000270383100077 | Publication Date | 2009-09-25 | |
| Series Editor | Series Title  |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links | ||
| Impact Factor | 3.836 | Times cited | Open Access | ||
| Notes | Approved | Most recent IF: 3.836; 2009 IF: 3.475 | |||
| Call Number | UA @ lucian @ | Serial | 4436 | ||
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| Author | Goodvin, G.L.; Covaci, L.; Berciu, M. | ||||
| Title | Holstein polarons near surfaces | Type | A1 Journal article | ||
| Year | 2009 | Publication | Physical Review Letters | Abbreviated Journal | Phys Rev Lett |
| Volume | 103 | Issue | 17 | Pages | 176402 |
| Keywords | A1 Journal article | ||||
| Abstract | We study the effects of a nearby surface on the spectral weight of a Holstein polaron, using the inhomogeneous momentum average approximation which is accurate over the entire range of electron-phonon (e-ph) coupling strengths. The broken translational symmetry is taken into account exactly. We find that the e-ph coupling gives rise to a large additional surface potential, with strong retardation effects, which may bind surface states even when they are not normally expected. The surface, therefore, has a significant effect and bulk properties are recovered only very far away from it. These results demonstrate that interpretation in terms of bulk quantities of spectroscopic data sensitive only to a few surface layers is not always appropriate. | ||||
| Address | Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1 | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Wos | 000271164500042 | Publication Date | 2009-10-22 |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Additional Links | ||
| Impact Factor | 8.462 | Times cited | 8 | Open Access | |
| Notes | Approved | Most recent IF: 8.462; 2009 IF: 7.328 | |||
| Call Number | UA @ lucian @ | Serial | 4435 | ||
| Permanent link to this record | |||||
| Author | Kim, W.; Covaci, L.; Marsiglio, F. | ||||
| Title | Impurity scattering of wave packets on a lattice | Type | A1 Journal article | ||
| Year | 2006 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 74 | Issue | 20 | Pages | 205120 |
| Keywords | A1 Journal article | ||||
| Abstract | Quantum transport in a lattice is distinct from its counterpart in continuum media. Even a free wave packet travels differently in a lattice than in the continuum. We describe quantum scattering in a one-dimensional lattice and illustrate characteristics of quantum transport such as resonant transmission. In particular we examine the transport characteristics of a random trimer model. We demonstrate the real-time propagation of a wave packet and its phase shift due to impurity configurations. Spin-flip scattering is also taken into account in a spin-chain system. We show how individual spins in the chain evolve as a result of a spin-flip interaction between an incoming electron and a spin chain. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000242409400030 | Publication Date | 2006-11-27 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links | ||
| Impact Factor | 3.836 | Times cited | 14 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2006 IF: 3.107 | |||
| Call Number | UA @ lucian @ | Serial | 4428 | ||
| Permanent link to this record | |||||
| Author | Kim, W.; Covaci, L.; Marsiglio, F. | ||||
| Title | Hidden symmetries of electronic transport in a disordered one-dimensional lattice | Type | A1 Journal article | ||
| Year | 2006 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 73 | Issue | 19 | Pages | 195109 |
| Keywords | A1 Journal article | ||||
| Abstract | Correlated, or extended, impurities play an important role in the transport properties of dirty metals. Here, we examine, in the framework of a tight-binding lattice, the transmission of a single electron through an array of correlated impurities. In particular we show that particles transmit through an impurity array in identical fashion, regardless of the direction of traversal. The demonstration of this fact is straightforward in the continuum limit, but requires a detailed proof for the discrete lattice. We also briefly demonstrate and discuss the time evolution of these scattering states, to delineate regions (in time and space) where the aforementioned symmetry is violated. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000237950400042 | Publication Date | 2006-05-11 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links | ||
| Impact Factor | 3.836 | Times cited | 5 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2006 IF: 3.107 | |||
| Call Number | UA @ lucian @ | Serial | 4429 | ||
| Permanent link to this record | |||||
| Author | Kim, W.; Covaci, L.; Dogan, F.; Marsiglio, F. | ||||
| Title | Quantum mechanics of spin transfer in coupled electron-spin chains | Type | A1 Journal article | ||
| Year | 2007 | Publication | Epl | Abbreviated Journal | Epl-Europhys Lett |
| Volume | 79 | Issue | 6 | Pages | 67004 |
| Keywords | A1 Journal article | ||||
| Abstract | The manner in which spin-polarized electrons interact with a magnetized thin film is currently described by a semi-classical approach. This in turn provides our present understanding of the spin transfer, or spin torque phenomenon. However, spin is an intrinsically quantum-mechanical quantity. Here, we make the first strides towards a fully quantum-mechanical description of spin transfer through spin currents interacting with a Heisenberg-coupled spin chain. Because of quantum entanglement, this requires a formalism based on the density matrix approach. Our description illustrates how individual spins in the chain time-evolve as a result of spin transfer. | ||||
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| Language | Wos | 000250409500023 | Publication Date | 2007-08-24 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0295-5075 | ISBN | Additional Links | ||
| Impact Factor | 1.957 | Times cited | 3 | Open Access | |
| Notes | Approved | Most recent IF: 1.957; 2007 IF: 2.206 | |||
| Call Number | UA @ lucian @ | Serial | 4430 | ||
| Permanent link to this record | |||||
| Author | Covaci, L.; Berciu, M. | ||||
| Title | Holstein polaron: The effect of coupling to multiple-phonon modes | Type | A1 Journal article | ||
| Year | 2007 | Publication | Epl | Abbreviated Journal | Epl-Europhys Lett |
| Volume | 80 | Issue | 6 | Pages | 67001 |
| Keywords | A1 Journal article | ||||
| Abstract | We investigate the effects of coupling to multiple-phonon modes on the properties of a Holstein polaron. To this end, we generalize the Momentum Average approximations MA((0)) and MA((1)) to deal with multiple-phonon modes. As for a single-phonon mode, these approximations are found to be numerically very efficient. They become exact for very weak or very strong couplings, and are highly accurate in the intermediate regimes, e.g. the spectral weights obey exactly the first six, respectively eight, sum rules. Our results show that the effect on ground-state properties is cumulative in nature. As a result, if the effective coupling to one mode is much larger than to all the others, this mode effectively determines the ground-state properties. However, even very weak coupling to a second phonon mode has important non-perturbational effects on the higher-energy spectrum, in particular on the dispersion and the phonon statistics of the polaron band. This has important consequences on the analysis and interpretation of data for real materials. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000251648300016 | Publication Date | 2007-11-30 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0295-5075 | ISBN | Additional Links | ||
| Impact Factor | 1.957 | Times cited | 9 | Open Access | |
| Notes | Approved | Most recent IF: 1.957; 2007 IF: 2.206 | |||
| Call Number | UA @ lucian @ | Serial | 4431 | ||
| Permanent link to this record | |||||
| Author | Marchand, D.; Covaci, L.; Berciu, M.; Franz, M. | ||||
| Title | Giant proximity effect in a phase-fluctuating superconductor | Type | A1 Journal article | ||
| Year | 2008 | Publication | Physical Review Letters | Abbreviated Journal | Phys Rev Lett |
| Volume | 101 | Issue | 9 | Pages | 097004 |
| Keywords | A1 Journal article | ||||
| Abstract | When a tunneling barrier between two superconductors is formed by a normal material that would be a superconductor in the absence of phase fluctuations, the resulting Josephson effect can undergo an enormous enhancement. We establish this novel proximity effect by a general argument as well as a numerical simulation and argue that it may underlie recent experimental observations of the giant proximity effect between two cuprate superconductors separated by a barrier made of the same material rendered normal by severe underdoping. | ||||
| Address | Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada V6T 1Z1 | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Wos | 000259195800055 | Publication Date | 2008-08-28 |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Additional Links | ||
| Impact Factor | 8.462 | Times cited | 17 | Open Access | |
| Notes | Approved | Most recent IF: 8.462; 2008 IF: 7.180 | |||
| Call Number | UA @ lucian @ | Serial | 4433 | ||
| Permanent link to this record | |||||
| Author | Covaci, L.; Berciu, M. | ||||
| Title | Polaron formation in the presence of Rashba spin-orbit coupling: implications for spintronics | Type | A1 Journal article | ||
| Year | 2009 | Publication | Physical Review Letters | Abbreviated Journal | Phys Rev Lett |
| Volume | 102 | Issue | 18 | Pages | 186403 |
| Keywords | A1 Journal article | ||||
| Abstract | We study the effects of the Rashba spin-orbit coupling on polaron formation, using a suitable generalization of the momentum average approximation. While previous work on a parabolic band model found that spin-orbit coupling increases the effective mass, we show that the opposite holds for a tight-binding model, unless both the spin-orbit and the electron-phonon couplings are weak. It is thus possible to lower the effective mass of the polaron by increasing the spin-orbit coupling. We also show that when the spin-orbit coupling is large as compared to the phonon energy, the polaron retains only one of the spin-polarized bands in its coherent spectrum. This has major implications for the propagation of spin-polarized currents in such materials, and thus for spintronic applications. | ||||
| Address | Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z1 | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Wos | 000265948600049 | Publication Date | 2009-05-08 |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Additional Links | ||
| Impact Factor | 8.462 | Times cited | 25 | Open Access | |
| Notes | Approved | Most recent IF: 8.462; 2009 IF: 7.328 | |||
| Call Number | UA @ lucian @ | Serial | 4434 | ||
| Permanent link to this record | |||||
| Author | Colin D. Judge, Nicolas Gauquelin, Lori Walters, Mike Wright, James I. Cole, James Madden, Gianluigi A. Botton, Malcolm Griffiths | ||||
| Title | Intergranular fracture in irradiated Inconel X-750 containing very high concentrations of helium and hydrogen | Type | A1 Journal Article | ||
| Year | 2015 | Publication | Journal of Nuclear Materials | Abbreviated Journal | |
| Volume | 457 | Issue | 457 | Pages | 165-172 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | In recent years, it has been observed that Inconel X-750 spacers in CANDU reactors exhibits lower ductility with reduced load carrying capacity following irradiation in a reactor environment. The fracture behaviour of ex-service material was also found to be entirely intergranular at high doses. The thermalized flux spectrum in a CANDU reactor leads to transmutation of 58Ni to 59Ni. The 59Ni itself has unusually high thermal neutron reaction cross-sections of the type: (n, γ), (n, p), and (n, α). The latter two reactions, in particular, contribute to a significant enhancement of the atomic displacements in addition to creating high concentrations of hydrogen and helium within the material. Microstructural examinations by transmission electron microscopy (TEM) have confirmed the presence of helium bubbles in the matrix and aligned along grain boundaries and matrix–precipitate interfaces. Helium bubble size and density are found to be highly dependent on the irradiation temperature and material microstructure; the bubbles are larger within grain boundary precipitates. TEM specimens extracted from fracture surfaces and crack tips provide information that is consistent with crack propagation along grain boundaries due to the presence of He bubbles. | ||||
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| Language | Wos | 000349169100022 | Publication Date | 2014-11-01 | |
| Series Editor | Series Title |
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| ISSN | ISBN | Additional Links | |||
| Impact Factor | Times cited | 29 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4540 | ||
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| Author | Macke, S.; Radi, A.; Hamann-Borrero, J.E.; Verna, A.; Bluschke, M.; Brück, S.; Goering, E.; Sutarto, R.; He, F.; Cristiani, G.; Wu, M.; Benckiser, E.; Habermeier, H.-U.; Logvenov, G.; Gauquelin, N.; Botton, G.A; Kajdos, A.P.; Stemmer, S.; Sawatzky,G.A.; Haverkort, M.W.; Keimer, B.; Hinkov, V. | ||||
| Title | Element Specific Monolayer Depth Profiling | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Advanced Materials | Abbreviated Journal | Adv Mater |
| Volume | 26 | Issue | 38 | Pages | 6554-6559 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) | ||||
| Abstract | The electronic phase behavior and functionality of interfaces and surfaces in complex materials are strongly correlated to chemical composition profiles, stoichiometry and intermixing. Here a novel analysis scheme for resonant X-ray reflectivity maps is introduced to determine such profiles, which is element specific and non-destructive, and which exhibits atomic-layer resolution and a probing depth of hundreds of nanometers. | ||||
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| Language | Wos | 000343763200004 | Publication Date | 2014-08-08 | |
| Series Editor | Series Title |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1521-4095 | ISBN | Additional Links | ||
| Impact Factor | 19.791 | Times cited | 34 | Open Access | |
| Notes | Approved | Most recent IF: 19.791; 2014 IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4541 | ||
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| Author | N. Gauquelin, D. G. Hawthorn, G. A. Sawatzky, R. X. Liang, D. A. Bonn, W. N. Hardy & G.A. Botton | ||||
| Title | Atomic scale real-space mapping of holes in YBa2Cu3O6+δ | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Nature Communications | Abbreviated Journal | |
| Volume | 5 | Issue | Pages | 4275 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The high-temperature superconductor YBa2Cu3O6+δ consists of two main structural units—a bilayer of CuO2 planes that are central to superconductivity and a CuO2+δ chain layer. Although the functional role of the planes and chains has long been established, most probes integrate over both, which makes it difficult to distinguish the contribution of each. Here we use electron energy loss spectroscopy to directly resolve the plane and chain contributions to the electronic structure in YBa2Cu3O6 and YBa2Cu3O7. We directly probe the charge transfer of holes from the chains to the planes as a function of oxygen content, and show that the change in orbital occupation of Cu is large in the chain layer but modest in CuO2 planes, with holes in the planes doped primarily into the O 2p states. These results provide direct insight into the local electronic structure and charge transfers in this important high-temperature superconductor. | ||||
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| Language | Wos | 000340615100002 | Publication Date | 2014-07-16 | |
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| Impact Factor | Times cited | 22 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4542 | ||
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| Author | Shuhui Sun, Gaixia Zhang, Nicolas Gauquelin, Ning Chen, Jigang Zhou, Songlan Yang, Weifeng Chen, Xiangbo Meng, Dongsheng Geng, Mohammad N. Banis, Ruying Li, Siyu Ye, Shanna Knights, Gianluigi A. Botton, Tsun-Kong Sham & Xueliang Sun | ||||
| Title | Single-atom Catalysis Using Pt/Graphene Achieved through Atomic Layer Deposition | Type | A1 Journal Article | ||
| Year | 2013 | Publication | Scientific Reports | Abbreviated Journal | |
| Volume | 3 | Issue | Pages | 1775 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Platinum-nanoparticle-based catalysts are widely used in many important chemical processes and automobile industries. Downsizing catalyst nanoparticles to single atoms is highly desirable to maximize their use efficiency, however, very challenging. Here we report a practical synthesis for isolated single Pt atoms anchored to graphene nanosheet using the atomic layer deposition (ALD) technique. ALD offers the capability of precise control of catalyst size span from single atom, subnanometer cluster to nanoparticle. The single-atom catalysts exhibit significantly improved catalytic activity (up to 10 times) over that of the state-of-the-art commercial Pt/C catalyst. X-ray absorption fine structure (XAFS) analyses reveal that the low-coordination and partially unoccupied densities of states of 5d orbital of Pt atoms are responsible for the excellent performance. This work is anticipated to form the basis for the exploration of a next generation of highly efficient single-atom catalysts for various applications. |
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| Language | Wos | 000318334300004 | Publication Date | 2013-05-03 | |
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| Impact Factor | Times cited | 345 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4543 | ||
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| Author | N. Gauquelin, E. Benckiser, M. K. Kinyanjui, M. Wu, Y. Lu, G. Christiani, G. Logvenov, H.-U. Habermeier, U. Kaiser, B. Keimer, and G. A. Botton | ||||
| Title | Atomically resolved EELS mapping of the interfacial structure of epitaxially strained LaNiO3/LaAlO3 superlattices | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Physical Review B | Abbreviated Journal | |
| Volume | 90 | Issue | Pages | 195140 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The interfacial atomic structure of a metallic LaNiO3/LaAlO3 superlattice grown on a LaSrAlO4 substrate was investigated using a combination of atomically resolved electron energy loss spectroscopy (EELS) at the Al K, Al L2,3, Sr L2,3, Ni L2,3, La M4,5, and O K edges as well as hybridization mapping of selected features of the O K-edge fine structure.We observe an additional La1−xSrxAl1−yNiyO3 layer at the substrate-superlattice interface, possibly linked to diffusion of Al and Sr into the growing film or a surface reconstruction due to Sr segregation. The roughness of the LaNiO3/LaAlO3 interfaces is found to be on average around one pseudocubic unit cell. The O K-edge EELS spectra revealed reduced spectral weight of the prepeak derived from Ni-O hybridized states in the LaNiO3 layers. We rule out oxygen nonstoichiometry of the LaNiO3 layers and discuss changes in the Ni-O hybridization due to heterostructuring as possible origin. |
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| Language | Wos | 000345467000003 | Publication Date | 2014-11-20 | |
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| Impact Factor | Times cited | 17 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4544 | ||
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| Author | M. K. Kinyanjui, N. Gauquelin, E. Benckiser, H. –U. Habermeier, B. Keimer, U. Kaiser and G.A. Botton | ||||
| Title | Local lattice distortion and anisotropic modulation in Epitaxially Strained LaNiO3/LaAlO3 hetero-structures | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Applied Physics Letters | Abbreviated Journal | |
| Volume | 104 | Issue | Pages | 221909 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Using a complementary combination of x-ray diffraction and atomically resolved imaging we investigated the lattice structure of epitaxial LaNiO3/LaAlO3 superlattices grown on a compressive-strain inducing LaSrAlO4 (001) substrate. A refinement of the structure obtained from the x-ray data revealed the monoclinic I 2/c 1 1 space group. The (Ni/Al)O6 octahedral rotation angle perpendicular to the superlattice plane is enhanced, and the one parallel to the plane is reduced with respect to the corresponding bulk values. High-angle annular dark field imaging was used to determine the lattice parameters within the superlattice unit cell. High-resolution electron microscopy images of the oxygen atoms are consistent with the x-ray results. | ||||
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| Language | Wos | 000337161700029 | Publication Date | 2014-06-07 | |
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| Impact Factor | Times cited | 22 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4545 | ||
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| Author | H. Zhang, N. Gauquelin, G.A. Botton and J.Y.T. Wei | ||||
| Title | Attenuation of superconductivity in manganite/cuprate heterostructures by epitaxially induced CuO intergrowths | Type | A1 Journal Article | ||
| Year | 2013 | Publication | Applied Physics Letters | Abbreviated Journal | |
| Volume | 103 | Issue | Pages | 052606 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | We examine the effect of CuO intergrowths on the superconductivity in epitaxial La 2/3 Ca 1/3 MnO 3 / YBa 2 Cu 3 O 7−δ La2/3Ca1/3MnO3/YBa2Cu3O7−δ (LCMO/YBCO) thin-film heterostructures. Scanning transmission electron microscopy on bilayer LCMO/YBCO thin films revealed double CuO-chain intergrowths which form regions with the 247 lattice structure in the YBCO layer. These nanoscale 247 regions do not appear in x-ray diffraction, but can physically account for the reduced critical temperature (Tc) of bilayer thin films relative to unilayer films with the same YBCO thickness, at least down to ∼25 nm. We attribute the CuO intergrowths to the bilayer heteroepitaxial mismatch and the Tc reduction to the generally lower Tc seen in bulk 247 samples. These epitaxially-induced CuO intergrowths provide a microstructural mechanism for the attenuation of superconductivity in LCMO/YBCO heterostructures. |
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| Language | Wos | 000322723000063 | Publication Date | 2013-08-02 | |
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| Impact Factor | Times cited | 12 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4546 | ||
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| Author | L. Zhang, J. Kim, J. Zhang, F. Nan, N. Gauquelin, G.A. Botton, P. He, R. Bashyam, S. Knights | ||||
| Title | Ti4O7 supported Ru@Pt core–shell catalyst for CO-tolerance in PEM fuel cell hydrogen oxidation reaction | Type | A1 Journal Article | ||
| Year | 2013 | Publication | Applied Energy | Abbreviated Journal | |
| Volume | 103 | Issue | March 2013 | Pages | 507-513 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | A new method is developed for synthesizing Ti4O7 supported Ru@Pt core–shell catalyst (Ru@Pt/Ti4O7) through pyrolysis followed by microwave irradiation. The purpose is to improve the Ru durability of PtRu from core–shell structure and strong bonding to Ti4O7 oxide. In this method, the first step is to co-reduce the mixture of ruthenium precursor and TiO2 in a H2 reducing atmosphere under heat-treatment to obtain a Ru core on Ti4O7 support, and the second step is to create a shell of platinum via microwave irradiation. Energy dispersive X-ray spectrometry, X-ray Diffraction, High-resolution Scanning Transmission Electron Microscopy with the high-angle annular dark-field method and Electron Energy-Loss Spectroscopy are used to demonstrate that this catalyst with larger particles has a core–shell structure with a Ru core and a Pt shell. Electrochemical measurements show Ru@Pt/Ti4O7 catalyst has a higher CO-tolerance capability than that of PtRu/C alloy catalyst. | ||||
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| Language | Wos | 000314669500048 | Publication Date | 2012-11-11 | |
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| Impact Factor | Times cited | 33 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4547 | ||
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| Author | Wang, W.; Patil, B.; Heijkers, S.; Hessel, V.; Bogaerts, A. | ||||
| Title | Nitrogen Fixation by Gliding Arc Plasma: Better Insight by Chemical Kinetics Modelling | Type | A1 Journal Article | ||
| Year | 2017 | Publication | Chemsuschem | Abbreviated Journal | Chemsuschem |
| Volume | 10 | Issue | 10 | Pages | 2110-2110 |
| Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | The conversion of atmospheric nitrogen into valuable compounds, that is, so-called nitrogen fixation, is gaining increased interest, owing to the essential role in the nitrogen cycle of the biosphere. Plasma technology, and more specifically gliding arc plasma, has great potential in this area, but little is known about the underlying mechanisms. Therefore, we developed a detailed chemical kinetics model for a pulsed-power gliding-arc reactor operating at atmospheric pressure for nitrogen oxide synthesis. Experiments are performed to validate the model and reasonable agreement is reached between the calculated and measured NO and NO2 yields and the corresponding energy efficiency for NOx formation for different N2/O2 ratios, indicating that the model can provide a realistic picture of the plasma chemistry. Therefore, we can use the model to investigate the reaction pathways for the formation and loss of NOx. The results indicate that vibrational excitation of N2 in the gliding arc contributes significantly to activating the N2 molecules, and leads to an energy efficient way of NOx production, compared to the thermal process. Based on the underlying chemistry, the model allows us to propose solutions on how to further improve the NOx formation by gliding arc technology. Although the energy efficiency of the gliding-arc-based nitrogen fixation process at the present stage is not comparable to the world-scale Haber–Bosch process, we believe our study helps us to come up with more realistic scenarios of entering a cutting-edge innovation in new business cases for the decentralised production of fertilisers for agriculture, in which lowtemperature plasma technology might play an important role. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | Publication Date | 2017-05-11 | ||
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1864-5631 | ISBN | Additional Links | ||
| Impact Factor | 7.226 | Times cited | Open Access | Not_Open_Access | |
| Notes | This research was supported by the European Marie Skłodowska- Curie Individual Fellowship “GlidArc” within Horizon 2020 (Grant No.657304), by the FWO project (grant G.0383.16 N) and by the EU project MAPSYN: Microwave, Acoustic and Plasma assisted SYNthesis, under the grant agreement no. CP-IP 309376 of the European Community’s Seventh Framework Program. 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: 7.226 | ||
| Call Number | PLASMANT @ plasmant @ | Serial | 4573 | ||
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| Author | Vladimirova, S.A.; Rumyantseva, M.N.; Filatova, D.G.; Chizhov, A.S.; Khmelevsky, N.O.; Konstantinova, E.A.; Kozlovsky, V.F.; Marchevsky, A.V.; Karakulina, O.M.; Hadermann, J.; Gaskov, A.M. | ||||
| Title | Cobalt location in p -CoO x / n -SnO 2 nanocomposites: Correlation with gas sensor performances | Type | A1 Journal Article | ||
| Year | 2017 | Publication | Journal Of Alloys And Compounds | Abbreviated Journal | J Alloy Compd |
| Volume | 721 | Issue | Pages | 249-260 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Nanocomposites CoOx/SnO2 based on tin oxide powders with different crystallinity have been prepared by wet chemical synthesis and characterized in detail by ICP-MS, XPS, EPR, XRD, HAADF-STEM imaging and EDX-STEM mapping. It was shown that cobalt is distributed differently between the bulk and surface of SnO2 nanocrystals, which depends on the crystallinity of the SnO2 matrix. The measurements of gas sensor properties have been carried out during exposure to CO (10 ppm), and H2S (2 ppm) in dry air. The decrease of sensor signal toward CO was attributed to high catalytic activity of Co3O4 leading to oxidation of carbon monoxide entirely on the surface of catalyst particles. The formation of a p-CoOx/n-SnO2 heterojunction results in high sensitivity of nanocomposites in H2S detection. The conductance significantly changed in the presence of H2S, which was attributed to the formation of metallic cobalt sulfide and removal of the p – n junction. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000405252400030 | Publication Date | 2017-06-02 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0925-8388 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.133 | Times cited | Open Access | Not_Open_Access | |
| Notes | This work was supported by ERA-Net.Plus grant N 096 FONSENS. EPR experiments were performed using the facilities of the Collective Use Center at the Moscow State University. | Approved | Most recent IF: 3.133 | ||
| Call Number | EMAT @ emat @ | Serial | 4711 | ||
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| Author | van der Torren, A.J.H.; Liao, Z.; Xu, C.; Gauquelin, N.; Yin, C.; Aarts, J.; van der Molen, S.J. | ||||
| Title | Formation of a conducting LaAlO3/SrTiO3 interface studied by low-energy electron reflection during growth | Type | A1 Journal Article | ||
| Year | 2017 | Publication | Physical Review Materials | Abbreviated Journal | Phys. Rev. Materials |
| Volume | 1 | Issue | 7 | Pages | 075001 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The two-dimensional electron gas occurring between the band insulators SrTiO 3 and LaAlO 3 continues to attract considerable interest, due to the possibility of dynamic control over the carrier density, and the ensuing phenomena such as magnetism and superconductivity. The formation of this conducting interface is sensitive to the growth conditions, but despite numerous investigations, there are still questions about the details of the physics involved. In particular, not much is known about the electronic structure of the growing LaAlO 3 layer at the growth temperature (around 800 ◦ C) in oxygen (pressure around 5 × 10 −5 mbar), since analysis techniques at these conditions are not readily available. We developed a pulsed laser deposition system inside a low-energy electron microscope in order to study this issue. The setup allows for layer-by-layer growth control and in-situ measurements of the angle-dependent electron reflection intensity, which can be used as a fingerprint of the electronic structure of the surface layers during growth. By using different substrate terminations and growth conditions we observe two families of reflectivity maps, which we can connect either to samples with an AlO 2 -rich surface and a conducting interface; or to samples with a LaO-rich surface and an insulating interface. Our observations emphasize that substrate termination and stoichiometry determine the electronic structure of the growing layer, and thereby the conductance of the interface. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000418770200003 | Publication Date | 2017-12-06 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2475-9953 | ISBN | Additional Links | ||
| Impact Factor | Times cited | 2 | Open Access | Not_Open_Access | |
| Notes | Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Fonds Wetenschappelijk Onderzoek, G.0044.13N ; European Cooperation in Science and Technology, MP 1308 ; We want to acknowledge Ruud Tromp, Daniel Gee- len, Johannes Jobst, Regina Dittmann, Gert Jan Koster, Guus Rijnders and Jo Verbeek for discussions and ad- vice and Ruud van Egmond and Marcel Hesselberth for technical assistance. This work was supported by the Netherlands Organization for Scientific Research (NWO) by means of an ”NWO Groot” grant and by the Leiden- Delft Consortium NanoFront. The work is part of the re- search programmes NWOnano and DESCO, which are fi- nanced by NWO. N.G. acknowledges funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge order- ing). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. We would also like to acknowledge networking support by the COST Action MP 1308 (COST TO-BE). | Approved | Most recent IF: NA | ||
| Call Number | EMAT @ emat @ | Serial | 4903 | ||
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| Author | Huygh, S.; Bogaerts, A.; Bal, K.M.; Neyts, E.C. | ||||
| Title | High Coke Resistance of a TiO2Anatase (001) Catalyst Surface during Dry Reforming of Methane | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 122 | Issue | 17 | Pages | 9389-9396 |
| Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | The resistance of a TiO2 anatase (001) surface to coke formation was studied in the context of dry reforming of methane using density functional theory (DFT) calculations. As carbon atoms act as precursors for coke formation, the resistance to coke formation can be measured by the carbon coverage of the surface. This is related to the stability of different CHx (x = 0−3) species and their rate of hydrogenation and dehydrogenation on the TiO2 surface. Therefore, we studied the reaction mechanisms and their corresponding rates as a function of the temperature for the dehydrogenation of the species on the surface. We found that the stabilities of C and CH are significantly lower than those of CH3 and CH2. The hydrogenation rates of the different species are significantly higher than the dehydrogenation rates in a temperature range of 300−1000 K. Furthermore, we found that dehydrogenation of CH3, CH2, and CH will only occur at appreciable rates starting from 600, 900, and 900 K, respectively. On the basis of these results, it is clear that the anatase (001) surface has a high coke resistance, and it is thus not likely that the surface will become poisoned by coke during dry reforming of methane. As the rate limiting step in dry reforming is the dissociative adsorption of CH4, we studied an alternative approach to thermal catalysis. We found that the temperature threshold for dry reforming is at least 700 K. This threshold temperature may be lowered by the use of plasma-catalysis, where the appreciable rates of adsorption of plasma-generated CHx radicals result in bypassing the rate limiting step of the reaction. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000431723700014 | Publication Date | 2018-05-03 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.536 | Times cited | 1 | Open Access | OpenAccess |
| Notes | Federaal Wetenschapsbeleid, IAP/7 ; Fonds Wetenschappelijk Onderzoek, G.0217.14N ; Onderzoeksfonds, Universiteit Antwerpen, 32249 ; | Approved | Most recent IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @c:irua:151529c:irua:152816 | Serial | 5000 | ||
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| Author | Barreca, D.; Gri, F.; Gasparotto, A.; Altantzis, T.; Gombac, V.; Fornasiero, P.; Maccato, C. | ||||
| Title | Insights into the Plasma-Assisted Fabrication and Nanoscopic Investigation of Tailored MnO2Nanomaterials | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Inorganic Chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 57 | Issue | 23 | Pages | 14564-14573 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Among transition metal oxides, MnO2 is of considerable importance for various technological end-uses,from heterogeneous catalysis to gas sensing, owing to its structural flexibility and unique properties at the nanoscale. In this work, we demonstrate the successful fabrication of supported MnO2 nanomaterials by a catalyst-free, plasmaassisted process starting from a fluorinated manganese(II) molecular source in Ar/O2 plasmas. A thorough multitechnique characterization aimed at the systematic investigation of material structure, chemical composition, and morphology revealed the formation of F-doped, oxygendeficient, MnO2-based nanomaterials, with a fluorine content tunable as a function of growth temperature (TG). Whereas phase-pure β-MnO2 was obtained for 100 °C ≤ TG ≤ 300 °C, the formation of mixed phase MnO2 + Mn2O3 nanosystems took place at 400 °C. In addition, the system nano-organization could be finely tailored, resulting in a controllable evolution from wheat-ear columnar arrays to high aspect ratio pointed-tip nanorod assemblies. Concomitantly, magnetic force microscopy analyses suggested the formation of spin domains with features dependent on material morphology. Preliminary tests in Vislight activated photocatalytic degradation of rhodamine B aqueous solutions pave the way to possible applications of the target materials in wastewater purification. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000452344400016 | Publication Date | 2018-12-03 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | Open Access | Not_Open_Access | |
| Notes | The present work was financially supported by Padova University DOR 2016−2018 and P-DiSC #03BIRD2016- UNIPD projects. T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO). Thanks are also due to Prof. Sara Bals (EMAT, University of Antwerp, Belgium) and to Dr. Giorgio Carraro (Department of Chemical Sciences, Padova University, Italy) for valuable support and experimental assistance. | Approved | Most recent IF: 4.857 | ||
| Call Number | EMAT @ emat @c:irua:156245 | Serial | 5147 | ||
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| Author | Bogaerts, A.; Snoeckx, R.; Trenchev, G.; Wang, W. | ||||
| Title | Modeling for a Better Understanding of Plasma-Based CO2 Conversion | Type | H1 Book Chapter | ||
| Year | 2018 | Publication | Plasma Chemistry and Gas Conversion | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | H1 Book Chapter; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | This chapter discusses modeling efforts for plasma-based CO2 conversion, which are needed to obtain better insight in the underlying mechanisms, in order to improve this application. We will discuss two types of (complementary) modeling efforts that are most relevant, that is, (i) modeling of the detailed plasma chemistry by zero-dimensional (0D) chemical kinetic models and (ii) modeling of reactor design, by 2D or 3D fluid dynamics models. By showing some characteristic calculation results of both models, for CO2 splitting and in combination with a H-source, and for packed bed DBD and gliding arc plasma, we can illustrate the type of information they can provide. | ||||
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| Publisher | IntechOpen | Place of Publication | Rijeka | Editor | Britun, N.; Silva, T. |
| Language | Wos | Publication Date | 2018-12-19 | ||
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record | ||
| Impact Factor | Times cited | Open Access | Not_Open_Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | PLASMANT @ plasmant @ Bogaerts18c:irua:155915 | Serial | 5142 | ||
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| Author | Kolev, S.; Bogaerts, A. | ||||
| Title | Three-dimensional modeling of energy transport in a gliding arc discharge in argon | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Plasma Sources Science & Technology | Abbreviated Journal | Plasma Sources Sci T |
| Volume | 27 | Issue | 12 | Pages | 125011 |
| Keywords | A1 Journal Article; gliding arc discharge, sliding arc discharge, energy transport, fluid plasma model, atmospheric pressure plasmas; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | In this work we study energy transport in a gliding arc discharge with two diverging flat electrodes in argon gas at atmospheric pressure. The discharge is ignited at the shortest electrode gap and it is pushed downstream by a forced gas flow. The current values considered are relatively low and therefore a non-equilibrium plasma is produced. We consider two cases, i.e. with high and low discharge current (28 mA and 2.8mA), and a constant gas flow of 10 lmin −1 , with a significant turbulent component to the velocity. The study presents an analysis of the various energy transport mechanisms responsible for the redistribution of Joule heating to the plasma species and the moving background gas. The objective of this work is to provide a general understanding of the role of the different energy transport mechanisms in arc formation and sustainment, which can be used to improve existing or new discharge designs. The work is based on a three-dimensional numerical model, combining a fluid plasma model, the shear stress transport Reynolds averaged Navier–Stokes turbulent gas flow model, and a model for gas thermal balance. The obtained results show that at higher current the discharge is constricted within a thin plasma column several hundred kelvin above room temperature, while in the low- current discharge the combination of intense convective cooling and low Joule heating prevents discharge contraction and the plasma column evolves to a static non-moving diffusive plasma, continuously cooled by the flowing gas. As a result, the energy transport in the two cases is determined by different mechanisms. At higher current and a constricted plasma column, the plasma column is cooled mainly by turbulent transport, while at low current and an unconstricted plasma, the major cooling mechanism is energy transport due to non-turbulent gas convection. In general, the study also demonstrates the importance of turbulent energy transport in redistributing the Joule heating in the arc and its significant role in arc cooling and the formation of the gas temperature profile. In general, the turbulent energy transport lowers the average gas temperature in the arc, thus allowing additional control of thermal non-equilibrium in the discharge. |
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| Language | Wos | 000454555600005 | Publication Date | 2018-12-28 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1361-6595 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.302 | Times cited | Open Access | Not_Open_Access | |
| Notes | This work was supported by the European Regional Devel- opment Fund within the Operational Programme ’Science and Education for Smart Growth 2014 – 2020’ under the Project CoE ’National center of mechatronics and clean technologies’ BG05M2OP001-1.001-0008-C01, and by the Flemish Fund for Scientific Research (FWO); grant no G.0383.16N. | Approved | Most recent IF: 3.302 | ||
| Call Number | PLASMANT @ plasmant @c:irua:155973 | Serial | 5140 | ||
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| Author | Kutukov, P.; Rumyantseva, M.; Krivetskiy, V.; Filatova, D.; Batuk, M.; Hadermann, J.; Khmelevsky, N.; Aksenenko, A.; Gaskov, A. | ||||
| Title | Influence of Mono- and Bimetallic PtOx, PdOx, PtPdOx Clusters on CO Sensing by SnO2 Based Gas Sensors | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Nanomaterials | Abbreviated Journal | Nanomaterials-Basel |
| Volume | 8 | Issue | 11 | Pages | 917 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | To obtain a nanocrystalline SnO2 matrix and mono- and bimetallic nanocomposites SnO2/Pd, SnO2/Pt, and SnO2/PtPd, a flame spray pyrolysis with subsequent impregnation was used. The materials were characterized using X-ray diffraction (XRD), a single-point BET method, transmission electron microscopy (TEM), and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) with energy dispersive X-ray (EDX) mapping. The electronic state of the metals in mono- and bimetallic clusters was determined using X-ray photoelectron spectroscopy (XPS). The active surface sites were investigated using the Fourier Transform infrared spectroscopy (FTIR) and thermo-programmed reduction with hydrogen (TPR-H-2) methods. The sensor response of blank SnO2 and nanocomposites had a carbon monoxide (CO) level of 6.7 ppm and was determined in the temperature range 60-300 degrees C in dry (Relative Humidity (RH) = 0%) and humid (RH = 20%) air. The sensor properties of the mono- and bimetallic nanocomposites were analyzed on the basis of information on the electronic state, the distribution of modifiers in SnO2 matrix, and active surface centers. For SnO2/PtPd, the combined effect of the modifiers on the electrophysical properties of SnO2 explained the inversion of sensor response from n- to p-types observed in dry conditions. | ||||
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| Language | Wos | 000451316100052 | Publication Date | 2018-11-07 | |
| Series Editor | Series Title |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2079-4991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.553 | Times cited | 7 | Open Access | Not_Open_Access |
| Notes | This research was funded by the Russian Ministry of Education and Sciences (Agreement No. 14.613.21.0075, RFMEFI61317X0075). | Approved | Most recent IF: 3.553 | ||
| Call Number | EMAT @ emat @c:irua:155767 | Serial | 5139 | ||
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| Author | Samaee, V.; Gatti, R.; Devincre, B.; Pardoen, T.; Schryvers, D.; Idrissi, H. | ||||
| Title | Dislocation driven nanosample plasticity: new insights from quantitative in-situ TEM tensile testing | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Scientific Reports | Abbreviated Journal | Sci Rep-Uk |
| Volume | 8 | Issue | 1 | Pages | 12012 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Intrinsic dislocation mechanisms in the vicinity of free surfaces of an almost FIB damage-free single crystal Ni sample have been quantitatively investigated owing to a novel sample preparation method combining twin-jet electro-polishing, in-situ TEM heating and FIB. The results reveal that the small-scale plasticity is mainly controlled by the conversion of few tangled dislocations, still present after heating, into stable single arm sources (SASs) as well as by the successive operation of these sources. Strain hardening resulting from the operation of an individual SAS is reported and attributed to the decrease of the length of the source. Moreover, the impact of the shortening of the dislocation source on the intermittent plastic flow, characteristic of SASs, is discussed. These findings provide essential information for the understanding of the regime of ‘dislocation source’ controlled plasticity and the related mechanical size effect. | ||||
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| Language | Wos | 000460200900001 | Publication Date | 2018-08-07 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2045-2322 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.259 | Times cited | 9 | Open Access | Not_Open_Access |
| Notes | Financial support from the Flemish (FWO) and German Research Foundation (DFG) through the European M-ERA.NET project “FaSS” (Fatigue Simulation near Surfaces) under the grant numbers GA.014.13 N and SCHW855/5-1, respectively, is gratefully acknowledged. V. Samaee also acknowledges the FWO research project G012012N “Understanding nanocrystalline mechanical behaviour from structural investigations”. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). Dr. Ruth Schwaiger is acknowledged for providing the Ni foils used to prepare the in-situ TEM tensile specimens. | Approved | Most recent IF: 4.259 | ||
| Call Number | EMAT @ emat @c:irua:155772 | Serial | 5136 | ||
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| Author | Lumbeeck, G.; Idrissi, H.; Amin-Ahmadi, B.; Favache, A.; Delmelle, R.; Samaee, V.; Proost, J.; Pardoen, T.; Schryvers, D. | ||||
| Title | Effect of hydriding induced defects on the small-scale plasticity mechanisms in nanocrystalline palladium thin films | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Journal Of Applied Physics | Abbreviated Journal | J Appl Phys |
| Volume | 124 | Issue | 22 | Pages | 225105 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Nanoindentation tests performed on nanocrystalline palladium films subjected to hydriding/dehydriding cycles demonstrate a significant softening when compared to the as-received material. The origin of this softening is unraveled by combining in situ TEM nanomechanical testing with automated crystal orientation mapping in TEM and high resolution TEM. The softening is attributed to the presence of a high density of stacking faults and of Shockley partial dislocations after hydrogen loading. The hydrogen induced defects affect the elementary plasticity mechanisms and the mechanical response by acting as preferential sites for twinning/detwinning during deformation. These results are analyzed and compared to previous experimental and simulation works in the literature. This study provides new insights into the effect of hydrogen on the atomistic deformation and cracking mechanisms as well as on the mechanical properties of nanocrystalline thin films and membranes. | ||||
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| Language | Wos | 000453254000025 | Publication Date | 2018-12-14 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.068 | Times cited | 2 | Open Access | Not_Open_Access |
| Notes | This work was supported by the Hercules Foundation under Grant No. AUHA13009, the Flemish Research Fund (FWO) under Grant No. G.0365.15N, and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. Dr. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). We would like to thank Dr. Hadi Pirgazi from UGent for his technical support to process the ACOM data in the OIM Analysis software. | Approved | Most recent IF: 2.068 | ||
| Call Number | EMAT @ emat @c:irua:155742 | Serial | 5135 | ||
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| Author | Vermeiren, V.; Bogaerts, A. | ||||
| Title | Supersonic Microwave Plasma: Potential and Limitations for Energy-Efficient CO2Conversion | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
| Volume | 122 | Issue | 45 | Pages | 25869-25881 |
| Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | Supersonic flows provide a high thermodynamic nonequilibrium, which is crucial for energy-efficient conversion of CO 2 in microwave plasmas and are therefore of great interest. However, the effect of the flow on the chemical reactions is poorly understood. In this work, we present a combined flow and plasma chemical kinetics model of a microwave CO 2 plasma in a Laval nozzle setup. The effects of the flow field on the different dissociation and recombination mechanisms, the vibrational distribution, and the vibrational transfer mechanism are discussed. In addition, the effect of experimental parameters, like position of power deposition, outlet pressure, and specific energy input, on the CO 2 conversion and energy efficiency is examined. The short residence time of the gas in the plasma region, the shockwave, and the maximum critical heat, and thus power, that can be added to the flow to avoid thermal choking are the main obstacles to reaching high energy efficiencies. |
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| Language | Wos | 000451101400016 | Publication Date | 2018-11-15 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.536 | Times cited | 5 | Open Access | Not_Open_Access |
| Notes | Fonds Wetenschappelijk Onderzoek, G.0383.16N ; | Approved | Most recent IF: 4.536 | ||
| Call Number | PLASMANT @ plasmant @c:irua:155412 | Serial | 5070 | ||
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| Author | Zhang, Q.-Z.; Bogaerts, A. | ||||
| Title | Capacitive electrical asymmetry effect in an inductively coupled plasma reactor | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Plasma Sources Science & Technology | Abbreviated Journal | Plasma Sources Sci T |
| Volume | 27 | Issue | 10 | Pages | 105019 |
| Keywords | A1 Journal Article; electrical asymmetry effect, inductively coupled plasma, self-bias, independent control of the ion fluxes and ion energy; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | The electrical asymmetry effect is realized by applying multiple frequency power sources (13.56 MHz and 27.12 MHz) to a capacitively biased substrate electrode in a specific inductively coupled plasma reactor. On the one hand, by adjusting the phase angle θ between the multiple frequency power sources, an almost linear self-bias develops on the substrate electrode, and consequently the ion energy can be well modulated, while the ion flux stays constant within a large range of θ. On the other hand, the plasma density and ion flux can be significantly modulated by tuning the inductive power supply, while only inducing a small change in the self- bias. Independent control of self-bias/ion energy and ion flux can thus be realized in this specific inductively coupled plasma reactor. |
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| Language | Wos | 000448434100001 | Publication Date | 2018-10-26 | |
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Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1361-6595 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.302 | Times cited | 1 | Open Access | Not_Open_Access |
| Notes | We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. | Approved | Most recent IF: 3.302 | ||
| Call Number | PLASMANT @ plasmant @c:irua:155506 | Serial | 5069 | ||
| Permanent link to this record | |||||
| Author | Zhang, Q.-Z.; Bogaerts, A. | ||||
| Title | Plasma streamer propagation in structured catalysts | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Plasma Sources Science & Technology | Abbreviated Journal | Plasma Sources Sci T |
| Volume | 27 | Issue | 10 | Pages | 105013 |
| Keywords | A1 Journal Article; plasma catalysis, streamer propagation, 3D structures, PIC/MCC; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | Plasma catalysis is gaining increasing interest for various environmental applications. Catalytic material can be inserted in different shapes in the plasma, e.g., as pellets, (coated) beads, but also as honeycomb monolith and 3DFD structures, also called ‘structured catalysts’, which have high mass and heat transfer properties. In this work, we examine the streamer discharge propagation and the interaction between plasma and catalysts, inside the channels of such structured catalysts, by means of a two-dimensional particle-in-cell/Monte Carlo collision model. Our results reveal that plasma streamers behave differently in various structured catalysts. In case of a honeycomb structure, the streamers are limited to only one channel, with low or high plasma density when the channels are parallel or perpendicular to the electrodes, respectively. In contrast, in case of a 3DFD structure, the streamers can distribute to different channels, causing discharge enhancement due to surface charging on the dielectric walls of the structured catalyst, and especially giving rise to a broader plasma distribution. The latter should be beneficial for plasma catalysis applications, as it allows a larger catalyst surface area to be exposed to the plasma. |
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000448131900002 | Publication Date | 2018-10-22 | |
| Series Editor | Series Title |
Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1361-6595 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.302 | Times cited | 3 | Open Access | Not_Open_Access |
| Notes | We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. | Approved | Most recent IF: 3.302 | ||
| Call Number | PLASMANT @ plasmant @c:irua:155510 | Serial | 5068 | ||
| Permanent link to this record | |||||
| Author | Schryvers, D.; Ma, Y.; Toth, L.; Tanner, L. | ||||
| Title | Electron microscopy study of twinning in the Ni5Al3 bainitic phase | Type | A3 Journal Article | ||
| Year | 1994 | Publication | TMS | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | A3 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | This contribution describes conventional and high resolution electron microscopy results on the different twinning arrangements in NisAl3 precipitates grown inside the B2 austenite phase. Short annealings introduce self-accommodating three-pointed star shaped precipitates consisting of twin related parts of different variants of the NisAl3 structure. Longer annealings result in plates growing separately from these wings and developing microtwinning in order to accommodate stress built-up at the interfaces with the surrounding matrix. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | Publication Date | 0000-00-00 | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | |||
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | EMAT @ emat @ | Serial | 5055 | ||
| Permanent link to this record | |||||