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Author Van den Broek, W.; Reed, B.W.; Béché, A.; Velazco, A.; Verbeeck, J.; Koch, C.T.
Title (up) Various compressed sensing setups evaluated against Shannon sampling under constraint of constant illumination Type A1 Journal article
Year 2019 Publication IEEE transactions on computational imaging Abbreviated Journal
Volume 5 Issue 3 Pages 502-514
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Under the constraint of constant illumination, an information criterion is formulated for the Fisher information that compressed sensing measurements in optical and transmission electron microscopy contain about the underlying parameters. Since this approach requires prior knowledge of the signal's support in the sparse basis, we develop a heuristic quantity, the detective quantum efficiency (DQE), that tracks this information criterion well without this knowledge. In this paper, it is shown that for the investigated choice of sensing matrices, and in the absence of read-out noise, i.e., with only Poisson noise present, compressed sensing does not raise the amount of Fisher information in the recordings above that of Shannon sampling. Furthermore, enabled by the DQE's analytical tractability, the experimental designs are optimized by finding out the optimal fraction of on pixels as a function of dose and read-out noise. Finally, we introduce a regularization and demonstrate, through simulations and experiment, that it yields reconstructions attaining minimum mean squared error at experimental settings predicted by the DQE as optimal.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000480352600013 Publication Date 2019-01-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2333-9403 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.546 Times cited 7 Open Access
Notes ; This work was supported by the Hercules fund from the Flemish Government (Qu-Ant-EM microscope used for the experimental data). The work of W. Van den Broek was supported by the DFG under Grant BR 5095/2-1 (Compressed sensing in ptychography and transmission electron microscopy). The work of A. Beche, A. Velazco, and J. Verbeeck was supported by the FWO under Grant G093417N (Compressed sensing enabling low dose imaging in transmission electron microscopy). The work of Christoph T. Koch was supported by the DFG under Grant CRC 951. The associate editor coordinating the review of this manuscript and approving it for publication was Dr. Chrysanthe Preza. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:161792 Serial 5368
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Author Ramaneti, R.; Sankaran, K.J.; Korneychuk, S.; Yeh, C.J.; Degutis, G.; Leou, K.C.; Verbeeck, J.; Van Bael, M.K.; Lin, I.N.; Haenen, K.
Title (up) Vertically aligned diamond-graphite hybrid nanorod arrays with superior field electron emission properties Type A1 Journal article
Year 2017 Publication APL materials Abbreviated Journal Apl Mater
Volume 5 Issue 6 Pages 066102
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A “patterned-seeding technique” in combination with a “nanodiamond masked reactive ion etching process” is demonstrated for fabricating vertically aligned diamond-graphite hybrid (DGH) nanorod arrays. The DGH nanorod arrays possess superior field electron emission (FEE) behavior with a low turn-on field, long lifetime stability, and large field enhancement factor. Such an enhanced FEE is attributed to the nanocomposite nature of theDGHnanorods, which contain sp(2)-graphitic phases in the boundaries of nano-sized diamond grains. The simplicity in the nanorod fabrication process renders the DGH nanorods of greater potential for the applications as cathodes in field emission displays and microplasma display devices. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license.
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Publisher Place of Publication Editor
Language Wos 000404623000002 Publication Date 2017-06-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2166-532x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.335 Times cited 16 Open Access
Notes The authors would like to thank the Methusalem “NANO” network for financial support and Mr. B. Ruttens and Professor Jan D'Haen for technical and experimental assistance. K.J. Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). Approved Most recent IF: 4.335
Call Number UA @ admin @ c:irua:152633 Serial 5369
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Author Li, Y.; Tan, H.; Yang, X.-Y.; Goris, B.; Verbeeck, J.; Bals, S.; Colson, P.; Cloots, R.; Van Tendeloo, G.; Su, B.-L.
Title (up) Well shaped Mn3O4 nano-octahedra with anomalous magnetic behavior and enhanced photodecomposition properties Type A1 Journal article
Year 2011 Publication Small Abbreviated Journal Small
Volume 7 Issue 4 Pages 475-483
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Very uniform and well shaped Mn3O4 nano-octahedra are synthesized using a simple hydrothermal method under the help of polyethylene glycol (PEG200) as a reductant and shape-directing agent. The nano-octahedra formation mechanism is monitored. The shape and crystal orientation of the nanoparticles is reconstructed by scanning electron microscopy and electron tomography, which reveals that the nano-octahedra only selectively expose {101} facets at the external surfaces. The magnetic testing demonstrates that the Mn3O4 nano-octahedra exhibit anomalous magnetic properties: the Mn3O4 nano-octahedra around 150 nm show a similar Curie temperature and blocking temperature to Mn3O4 nanoparticles with 10 nm size because of the vertical axis of [001] plane and the exposed {101} facets. With these Mn3O4 nano-octahedra as a catalyst, the photodecomposition of rhodamine B is evaluated and it is found that the photodecomposition activity of Mn3O4 nano-octahedra is much superior to that of commercial Mn3O4 powders. The anomalous magnetic properties and high superior photodecomposition activity of well shaped Mn3O4 nano-octahedra should be related to the special shape of the nanoparticles and the abundantly exposed {101} facets at the external surfaces. Therefore, the shape preference can largely broaden the application of the Mn3O4 nano-octahedra.
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Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000288080400008 Publication Date 2011-01-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1613-6810; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.643 Times cited 131 Open Access
Notes This work was realized in the frame of an Interuniversity Attraction Poles Program (Inanomat-P6/17)-Belgian State-Belgian Science Policy and the project “Redugaz”, financially supported by the European community and the Wallon government in the frame of Interreg IV (France-Wallonie). B. L. S. acknowledges the Chinese Central Government for an “Expert of the State” position in the program of “Thousand talents” and the Chinese Ministry of Education for a Changjiang Scholar position at the Wuhan University of Technology. H. T. acknowledges the financial support from FWO-Vlaanderen (Project nr. G.0147.06). J.V. thanks the financial support from the European Union under Framework 6 program for Integrated Infrastructure Initiative, Reference 026019 ESTEEM. Approved Most recent IF: 8.643; 2011 IF: 8.349
Call Number UA @ lucian @ c:irua:87908 Serial 3914
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Author Guda, A.A.; Smolentsev, N.; Verbeeck, J.; Kaidashev, E.M.; Zubavichus, Y.; Kravtsova, A.N.; Polozhentsev, O.E.; Soldatov, A.V.
Title (up) X-ray and electron spectroscopy investigation of the coreshell nanowires of ZnO:Mn Type A1 Journal article
Year 2011 Publication Solid state communications Abbreviated Journal Solid State Commun
Volume 151 Issue 19 Pages 1314-1317
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract ZnO/ZnO:Mn coreshell nanowires were studied by means of X-ray absorption spectroscopy of the Mn K- and L2,3-edges and electron energy loss spectroscopy of the O K-edge. The combination of conventional X-ray and nanofocused electron spectroscopies together with advanced theoretical analysis turned out to be fruitful for the clear identification of the Mn phase in the volume of the coreshell structures. Theoretical simulations of spectra, performed using the full-potential linear augmented plane wave approach, confirm that the shell of the nanowires, grown by the pulsed laser deposition method, is a real dilute magnetic semiconductor with Mn2+ atoms at the Zn sites, while the core is pure ZnO.
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Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000295492200003 Publication Date 2011-06-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.554 Times cited 12 Open Access
Notes We acknowledge the Helmholtz-Zentrum Berlin – Electron storage ring BESSY-II for provision of synchrotron radiation at the Russian-German beamline and financial support. This research was supported by the Russian Ministry to education and science (RPN 2.1.1. 5932 grant and RPN 2.1.1.6758 grant). N.S. and A.G. would like to thank the Russian Ministry of Education for providing the fellowships of President of Russian Federation to study abroad. We would like to thank the UGINFO computer center of Southern federal university for providing the computer time. Approved Most recent IF: 1.554; 2011 IF: 1.649
Call Number UA @ lucian @ c:irua:92831 Serial 3925
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