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Author | Zhang, S.; Sahin, H.; Torun, E.; Peeters, F.; Martien, D.; DaPron, T.; Dilley, N.; Newman, N. | ||||
Title | Fundamental mechanisms responsible for the temperature coefficient of resonant frequency in microwave dielectric ceramics | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of the American Ceramic Society | Abbreviated Journal | J Am Ceram Soc |
Volume | 100 | Issue | 100 | Pages | 1508-1516 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The temperature coefficient of resonant frequency ((f)) of a microwave resonator is determined by three materials parameters according to the following equation: (f)=-(1/2 (epsilon) + 1/2 + (L)), where (L), (epsilon), and are defined as the linear temperature coefficients of the lattice constant, dielectric constant, and magnetic permeability, respectively. We have experimentally determined each of these parameters for Ba(Zn1/3Ta2/3)O-3, 0.8 at.% Ni-doped Ba(Zn1/3Ta2/3)O-3, and Ba(Ni1/3Ta2/3)O-3 ceramics. These results, in combination with density functional theory calculations, have allowed us to develop a much improved understanding of the fundamental physical mechanisms responsible for the temperature coefficient of resonant frequency, (f). | ||||
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Publisher | Place of Publication | Columbus, Ohio | Editor | ||
Language | Wos | 000399610800034 | Publication Date | 2017-02-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7820 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.841 | Times cited | 6 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.841 | ||
Call Number | UA @ lucian @ c:irua:143682 | Serial | 4597 | ||
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Author | Zhang, Y.; Wang, H.-yu; Zhang, Y.-ru; Bogaerts, A. | ||||
Title | Formation of microdischarges inside a mesoporous catalyst in dielectric barrier discharge plasmas | Type | A1 Journal article | ||
Year | 2017 | Publication | Plasma sources science and technology | Abbreviated Journal | Plasma Sources Sci T |
Volume | 26 | Issue | 26 | Pages | 054002 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The formation process of a microdischarge (MD) in both μm- and nm-sized catalyst pores is simulated by a two-dimensional particle-in-cell/Monte Carlo collision model. A parallel-plate dielectric barrier discharge configuration in filamentary mode is considered in ambient air. The discharge is powered by a high voltage pulse. Our calculations reveal that a streamer can penetrate into the surface features of a porous catalyst and MDs can be formed inside both μm- and nm-sized pores, yielding ionization inside the pore. For the μm-sized pores, the ionization mainly occurs inside the pore, while for the nm-sized pores the ionization is strongest near and inside the pore. Thus, enhanced discharges near and inside the mesoporous catalyst are observed. Indeed, the maximum values of the electric field, ionization rate and electron density occur near and inside the pore. The maximum electric field and electron density inside the pore first increase when the pore size rises from 4 nm to 10 nm, and then they decrease for the 100 nm pore, due to a more pronounced surface discharge for the smaller pores. However, the ionization rate is highest for the 100 nm pore due to the largest effective ionization region. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000399277700001 | Publication Date | 2017-04-05 | |
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 | 15 | Open Access | OpenAccess |
Notes | This work was supported by the NSFC (11405067, 11275007, 11375163). Y Zhang gratefully acknowledges the Belgian Federal Science Policy Office for financial support. The authors are very grateful to Wei Jiang for the useful discussions on the photo-ionization model and the particle-incell/ Monte-Carlo model. | Approved | Most recent IF: 3.302 | ||
Call Number | PLASMANT @ plasmant @ c:irua:142806 | Serial | 4566 | ||
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Author | Zhao, H.J.; Misko, V.R.; Tempere, J.; Nori, F. | ||||
Title | Pattern formation in vortex matter with pinning and frustrated intervortex interactions | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 95 | Issue | 95 | Pages | 104519 |
Keywords | A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the effects related to vortex-core deformations when vortices approach each other. As a result of these vortex-core deformations, the vortex-vortex interaction effectively acquires an attractive component leading to a variety of vortex patterns typical for systems with nonmonotonic repulsive-attractive interaction, such as stripes and labyrinths. The core deformations are anisotropic and can induce frustration in the vortex-vortex interaction. In turn, this frustration has an impact on the resulting vortex patterns, which are analyzed in the presence of additional random pinning, as a function of the pinning strength. This analysis can be applicable to vortices in multiband superconductors or to vortices in Bose-Einstein condensates. | ||||
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Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000399138800006 | Publication Date | 2017-03-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 5 | Open Access | |
Notes | ; We acknowledge fruitful discussions with E. Babaev and V. Gladilin. This work is partially supported by the Natural Science Foundation of Jiangsu Province (Grant No. BK20150595), the National Natural Science Foundation of China (Grants No. NSFC-U1432135, No. 11611140101, and No. 11674054), the “Odysseus” program of the Flemish Government and Flemish Research Foundation (FWO-Vl), the Flemish Research Foundation (through Projects No. G.0115.12N, No. G.0119.12N, No. G.0122.12N, and No. G.0429.15N), the Research Fund of the University of Antwerp, the RIKEN iTHES Project, the MURI Center for Dynamic Magneto-Optics via the AFOSR Award No. FA9550-14-1-0040, the IMPACT program of JST, a Grant-in-Aid for Scientific Research (A), the Japan Society for the Promotion of Science (KAKENHI), CREST, and a grant from the John Templeton Foundation. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:142429 | Serial | 4602 | ||
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Author | Zheng, G.; Chen, Z.; Sentosun, K.; Pérez-Juste, I.; Bals, S.; Liz-Marzán, L.M.; Pastoriza-Santos, I.; Pérez-Juste, J.; Hong, M. | ||||
Title | Shape control in ZIF-8 nanocrystals and metal nanoparticles@ZIF-8 heterostructures | Type | A1 Journal article | ||
Year | 2017 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 9 | Issue | 9 | Pages | 16645-16651 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Shape control in metal-organic frameworks still remains a challenge. We propose a strategy based on the capping agent modulator method to control the shape of ZIF-8 nanocrystals. This approach requires the use of a surfactant, cetyltrimethylammonium bromide (CTAB), and a second capping agent, tris(hydroxymethyl)aminomethane (TRIS), to obtain ZIF-8 nanocrystals with morphology control in aqueous media. Semiempirical computational simulations suggest that both shape-inducing agents adsorb onto different surface facets of ZIF-8, thereby slowing down their crystal growth rates. While CTAB molecules preferentially adsorb onto the {100} facets, leading to ZIF-8 particles with cubic morphology, TRIS preferentially stabilizes the {111} facets, inducing the formation of octahedral crystals. Interestingly, the presence of both capping agents leads to nanocrystals with irregular shapes and higher index facets, such as hexapods and burr puzzles. Additionally, the combination of ZIF-8 nanocrystals with other materials is expected to impart additional properties due to the hybrid nature of the resulting nanocomposites. In the present case, the presence of CTAB and TRIS molecules as capping agents facilitates the synthesis of metal nanoparticle@ZIF-8 nanocomposites, due to synergistic effects which could be of use in a number of applications such as catalysis, gas sensing and storage. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000414960900015 | Publication Date | 2017-07-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 109 | Open Access | OpenAccess |
Notes | This work was supported by the Ministerio de Economía y Competitividad (MINECO, Spain), under the Grants MAT2013- 45168-R and MAT2016-77809-R. This study was also funded by the Xunta de Galicia/FEDER (ED431C 2016-048). We are grateful to the financial support from National Natural Science Foundation of China (21671010), Guangdong Science and Technology Program (2013A061401002), and Shenzhen Strategic Emerging Industries (KQCX2015032709315529, CXZZ20140419131807788). | Approved | Most recent IF: 7.367 | ||
Call Number | EMAT @ emat @c:irua:145827UA @ admin @ c:irua:145827 | Serial | 4705 | ||
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Author | Zhong, Z.; Goris, B.; Schoenmakers, R.; Bals, S.; Batenburg, K.J. | ||||
Title | A bimodal tomographic reconstruction technique combining EDS-STEM and HAADF-STEM | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 174 | Issue | 174 | Pages | 35-45 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A three-dimensional (3D) chemical characterization of nanomaterials can be obtained using tomography based on high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) or energy dispersive X-ray spectroscopy (EDS) STEM. These two complementary techniques have both advantages and disadvantages. The Z-contrast images have good image quality but lack robustness in the compositional analysis, while the elemental maps give more element-specific information, but at a low signal-to-noise ratio and a longer exposure time. Our aim is to combine these two types of complementary information in one single tomographic reconstruction process. Therefore, an imaging model is proposed combining both HAADF-STEM and EDS-STEM. Based on this model, the elemental distributions can be reconstructed using both types of information simultaneously during the reconstruction process. The performance of the new technique is evaluated using simulated data and real experimental data. The results demonstrate that combining two imaging modalities leads to tomographic reconstructions with suppressed noise and enhanced contrast. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000403342200005 | Publication Date | 2016-12-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 26 | Open Access | OpenAccess |
Notes | This research is supported by the Dutch Technology Foundation STW (http://www.stw.nl/), which is part of the Netherlands Organization for Scientific Research (NWO), and which is partly funded by the Ministry of Economic Affairs, Agriculture and Innovation under project number 13314. It is also supported by the Flemish research foundation (FWO Vlaanderen) by project funding (G038116N) and a postdoctoral research grant to B.G. Funding from the European Research Council (Starting Grant No. COLOURATOMS 335078) is acknowledged by S.B. The authors would like to thank Dr. Bernd Rieger and Dr. Richard Aveyard for useful discussions, and Prof. Dr. Luis M. Liz-Marzan for providing the investigated samples. We also acknowledge COST Action MP1207 for networking support. (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:141719UA @ admin @ c:irua:141719 | Serial | 4484 | ||
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Author | Zhou, Y.; Ramaneti, R.; Anaya, J.; Korneychuk, S.; Derluyn, J.; Sun, H.; Pomeroy, J.; Verbeeck, J.; Haenen, K.; Kuball, M. | ||||
Title | Thermal characterization of polycrystalline diamond thin film heat spreaders grown on GaN HEMTs | Type | A1 Journal article | ||
Year | 2017 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 111 | Issue | 4 | Pages | 041901 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Polycrystalline diamond (PCD) was grown onto high-k dielectric passivated AlGaN/GaN-on-Si high electron mobility transistor (HEMT) structures, with film thicknesses ranging from 155 to 1000 nm. Transient thermoreflectance results were combined with device thermal simulations to investigate the heat spreading benefit of the diamond layer. The observed thermal conductivity (k(Dia)) of PCD films is one-to-two orders of magnitude lower than that of bulk PCD and exhibits a strong layer thickness dependence, which is attributed to the grain size evolution. The films exhibit a weak temperature dependence of k(Dia) in the measured 25-225 degrees C range. Device simulation using the experimental jDia and thermal boundary resistance values predicts at best a 15% reduction in peak temperature when the source-drain opening of a passivated AlGaN/GaN-on-Si HEMT is overgrown with PCD. Published by AIP Publishing. | ||||
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Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000406779700008 | Publication Date | 2017-07-24 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 78 | Open Access | Not_Open_Access |
Notes | ; The authors are grateful to Professor Michael Uren and Dr. Roland B. Simon (University of Bristol) for helpful discussions and to Dr. Sien Drijkoningen (Hasselt University) for taking the SEM micrographs. This work was in part supported by DARPA under Contract No. FA8650-15-C-7517, monitored by Dr. Avram Bar Cohen and Dr. John Blevins, and supported by Dr. Joseph Maurer and Dr. Abirami Sivananthan. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of DARPA. Y.Z. acknowledges China Scholarship Council for the financial support. S.K. and J.V. acknowledge the FWO-Vlaanderen for financial support under contract G.0044.13N “Charge ordering.” ; | Approved | Most recent IF: 3.411 | ||
Call Number | UA @ lucian @ c:irua:145203 | Serial | 4728 | ||
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Author | Zhuge, X.; Jinnai, H.; Dunin-Borkowski, R.E.; Migunov, V.; Bals, S.; Cool, P.; Bons, A.-J.; Batenburg, K.J. | ||||
Title | Automated discrete electron tomography – Towards routine high-fidelity reconstruction of nanomaterials | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 175 | Issue | 175 | Pages | 87-96 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Electron tomography is an essential imaging technique for the investigation of morphology and 3D structure of nanomaterials. This method, however, suffers from well-known missing wedge artifacts due to a restricted tilt range, which limits the objectiveness, repeatability and efficiency of quantitative structural analysis. Discrete tomography represents one of the promising reconstruction techniques for materials science, potentially capable of delivering higher fidelity reconstructions by exploiting the prior knowledge of the limited number of material compositions in a specimen. However, the application of discrete tomography to practical datasets remains a difficult task due to the underlying challenging mathematical problem. In practice, it is often hard to obtain consistent reconstructions from experimental datasets. In addition, numerous parameters need to be tuned manually, which can lead to bias and non-repeatability. In this paper, we present the application of a new iterative reconstruction technique, named TVR-DART, for discrete electron tomography. The technique is capable of consistently delivering reconstructions with significantly reduced missing wedge artifacts for a variety of challenging data and imaging conditions, and can automatically estimate its key parameters. We describe the principles of the technique and apply it to datasets from three different types of samples acquired under diverse imaging modes. By further reducing the available tilt range and number of projections, we show that the proposed technique can still produce consistent reconstructions with minimized missing wedge artifacts. This new development promises to provide the electron microscopy community with an easy-to-use and robust tool for high-fidelity 3D characterization of nanomaterials. |
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Language | Wos | 000403342500008 | Publication Date | 2017-01-24 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 22 | Open Access | OpenAccess |
Notes | This work has been supported in part by the Stichting voor de Technische Wetenschappen (STW) through a personal grant (Veni,13610), and was in part by ExxonMobil Chemical Europe Inc. The authors further acknowledge financial support from the University of Antwerp through BOF GOA funding. S.B. acknowledges financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). R.D.B. is grateful for funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007–2013)/ ERC grant agreement number 320832. Thomas Altantzis is gratefully acknowledged for acquiring the Anatase nanosheets dataset. (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:141218UA @ admin @ c:irua:141218 | Serial | 4485 | ||
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Author | Zografos, O.; Dutta, S.; Manfrini, M.; Vaysset, A.; Sorée, B.; Naeemi, A.; Raghavan, P.; Lauwereins, R.; Radu, I.P. | ||||
Title | Non-volatile spin wave majority gate at the nanoscale | Type | A1 Journal article | ||
Year | 2017 | Publication | AIP advances T2 – 61st Annual Conference on Magnetism and Magnetic Materials (MMM), OCT 31-NOV 04, 2016, New Orleans, LA | Abbreviated Journal | Aip Adv |
Volume | 7 | Issue | 5 | Pages | 056020 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | A spin wave majority fork-like structure with feature size of 40 nm, is presented and investigated, through micromagnetic simulations. The structure consists of three merging out-of-plane magnetization spin wave buses and four magneto-electric cells serving as three inputs and an output. The information of the logic signals is encoded in the phase of the transmitted spin waves and subsequently stored as direction of magnetization of the magneto-electric cells upon detection. The minimum dimensions of the structure that produce an operational majority gate are identified. For all input combinations, the detection scheme employed manages to capture the majority phase result of the spin wave interference and ignore all reflection effects induced by the geometry of the structure. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). | ||||
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Publisher | Amer inst physics | Place of Publication | Melville | Editor | |
Language | Wos | 000402797100177 | Publication Date | 2017-02-06 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 2158-3226 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.568 | Times cited | 13 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 1.568 | ||
Call Number | UA @ lucian @ c:irua:144288 | Serial | 4673 | ||
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Author | Zografos, O.; Manfrini, M.; Vaysset, A.; Sorée, B.; Ciubotaru, F.; Adelmann, C.; Lauwereins, R.; Raghavan, P.; Radu, I.P. | ||||
Title | Exchange-driven magnetic logic | Type | A1 Journal article | ||
Year | 2017 | Publication | Scientific reports | Abbreviated Journal | Sci Rep-Uk |
Volume | 7 | Issue | Pages | 12154 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Direct exchange interaction allows spins to be magnetically ordered. Additionally, it can be an efficient manipulation pathway for low-powered spintronic logic devices. We present a novel logic scheme driven by exchange between two distinct regions in a composite magnetic layer containing a bistable canted magnetization configuration. By applying a magnetic field pulse to the input region, the magnetization state is propagated to the output via spin-to-spin interaction in which the output state is given by the magnetization orientation of the output region. The dependence of this scheme with input field conditions is extensively studied through a wide range of micromagnetic simulations. These results allow different logic operating modes to be extracted from the simulation results, and majority logic is successfully demonstrated. | ||||
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Publisher | Nature Publishing Group | Place of Publication | London | Editor | |
Language | Wos | 000411434900020 | Publication Date | 2017-09-18 | |
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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 | 7 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 4.259 | ||
Call Number | UA @ lucian @ c:irua:146742 | Serial | 4784 | ||
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