101,903 research outputs found
Electron energy loss-near edge structure as a fingerprint for identifying chromium nitrides
No full textElectron energy loss-near edge structure as a fingerprint for identifying chromium nitrides
C. Mitterbauer Corresponding Author Contact Information, E-mail The Corresponding Author, a, C. Hébert b, G. Kothleitner a, F. Hofer a, P. Schattschneider b and H. W. Zandbergen c
a Research Institute for Electron Microscopy, Graz University of Technology, Steyrergasse 17, A-8010, Graz, Austria
b Institute for Solid State Physics, Vienna University of Technology, Wiedner Hauptstraße 8-10/138, A-1040, Wien, Austria
c Laboratory of Materials Science, Centre for HREM, Delft University of Technology, Rotterdamseweg 137, 2628 AL, Delft, The Netherlands
Received 5 December 2003; accepted 30 January 2004 by H. Eschrig Available online 11 February 2004.
Abstract
Electron energy-loss near-edge structure data for the N K and the Cr L2,3 edges of CrN and Cr2N have been acquired in order to distinguish between these chromium nitride modifications. The N K edge spectra of these compounds have been modelled using both band structure and multiple scattering methods. We compare the results of these calculations with the experimental edges which have been recorded using a conventional transmission electron microscope (TEM) as well as a monochromated TEM (Wien filter).
Author Keywords: Author Keywords: A. Chromium nitride; C. Scanning and transmission electron microscopy; E. Electron energy loss spectroscopy
82.80.Pv; 61.16.Bg; 71.20.−b; 11.80.L
Transition metal oxide-doped mesostructured silica films
No full textMixed metal oxide-doped mesostructured silica films have been prepared by a combination of a ligand-assisted templating (LAT) and solvent evaporation-induced self-assembly (EISA) approach using metal alkoxides as precursors. To overcome the problem of the different hydrolysis and condensation rates of the various alkoxide precursors (silicon alkoxides and transition metal alkoxides), the hydrophilic head group of oligo(ethylene oxide) containing surfactants was coordinated to the M(OR)x groups resulting in metal-containing surfactants. These novel surfactants serve different functions in the EISA process: first, they moderate the hydrolysis and condensation rate of the transition metal alkoxide; second, they allow for a positioning of the transition metal alkoxide within the silica matrix; and third, they act as structure-directing agents. The obtained films are characterized by a high loading of the transition metal oxide species within the silica matrix and a homogeneous distribution throughout the whole film as shown by X-ray photoelectron (XPS) and extended X-ray absorption fine structure (EXAFS) spectroscopy. Several transition metal oxides have been incorporated into the silica matrix such as titania, zirconia and tantalum oxide
Bibliographie Hilarion G. Petzold 1958 – 2009 mit Anhang als Einführung
No full textDieses Archiv enthält die Gesamtbibliographie der Werke des Autors nebst einiger Texte „Über H. G. Petzold“ im Schlussteil der Bibliographie sowie einen Anhang mit einer Einführung in die Architektur des Werkes in seinem wissenslogischen Aufbau als Ausarbeitung seines „Tree of Science Modells“ (2007).This archive contains the complete bibliography of the author and some texts about H. G. Petzold, moreover an epilogue with an introduction to the architecture of the works in its epistemological structure and composition and as an elaborations of Petzold’s „Tree of Science Modell (2007).https://www.fpi-publikation.de/polyloge/01-2009-petzold-h-g-gesamtbibliographie-h-g-petzold-1958-2009-updating-november2009/peerReviewedpublishedVersio
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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3346: Samuel G. Freedman, author, 2013
No full textPhotograph of author Samuel G. Freedman, at NT Daily Slash meeting in the Mayborn School of Journalism at UNT
The Right to Strike under the United States Constitution: Theory, Practice, and Possible Implications for Canada
No full textAnswering critics of the Canadian Supreme Court's judgment in B.C. Health, the author argues that the Court laid the foundation for a principled and durable doctrine protecting constitutional labour rights, one that goes directly to the heart of the matter — the inequality of workers’ power in the employment relation. In the author’s view, two paths could lead from B.C. Health to the recognition of Charter protec- tion for a right to strike: one that treats the right as an accessory to col- lective bargaining, and one that upholds the right directly on the basis of the Charter values of equality and participation. The author supports the latter approach, contending that constitutional rights should be defined in relation to fundamental values, in a way that is not contingent on time-bound or fact-sensitive assessments about the role of strikes within a particular collective bargaining regime. Although a Charter right to strike may involve the courts in difficult choices about when to defer to legislative policy decisions, and courts may lack the institutional capac- ity to deal effectively with labour law issues, the author points out that judges can look to ILO standards for expert guidance. Noting that the U.S. experience in this area might be of considerable use to Canadians, the author concludes by providing an overview of American case law concerning a constitutional right to strike.Peer reviewe
Multiple beam interference and diffraction with FIB fabricated nano-slits
No full textThe recent advances in nanotechnology and electron microscopy are making today possible the realization of experiments of diffraction and interference at multiple slits which formerly were carried out with extremely skilled specimen preparation techniques and dedicated electron optical apparatus [1]. Recently we have used the focused ion beam (FIB) to fabricate two slits on a commercial silicon nitride membrane (500 nm thick) suspended on a 100x100m2 silicon frame 200m thick. In that case the Fraunhofer image was observed in a conventional TEM-JEOL 2010 [2].Here we adopt a less expensive support for nano-slits fabrication, consisting of a commercial continuous carbon film on a standard copper grid, which was subsequently coated with a gold layer about 120 nm in thickness. The slits (nominally 80nm wide, 420 nm spaced) were fabricated with a 9 pA, 30keV, Ga+ beam of a FEI Strata235M Dual Beam. The quality of the slits is very good, as shown in Fig. 1(a) and Fig.1(b), that display two and three slits, respectively. An additional advantage of these samples with respect to the previous ones, is that they can be inserted in almost all FEG-TEM specimen holders. The diffraction and interference experiments were carried out with a JEM-2200FS electron microscope. Owing to the larger coherence of the FEG with respect to the thermionic source, it has been possible to record interference and diffraction images with exposure times of few seconds.The three-slit case is illustrated in Fig. 2 where the in focus image (a), and the images taken at a nominal defocus of -10 mm (b), -20 mm (c) and -40 mm (d), are reported. This sequence shows the transition from the nearly separated Fresnel diffraction images of the single slits, (b), to their subsequent overlapping as the defocus increases, displaying interference phenomena, (c), and finally to a nearly Fraunhofer image, (d).Fig. 3 displays the true Fraunhofer image, taken at a nominal defocus of -53 mm, which clearly shows the secondary minima between the more intense maxima. In the same figure the single slit Fraunhofer images corresponding to the longer side of the slits can also be observed
G-Rank: Unsupervised Continuous Learn-to-Rank for Edge Devices in a P2P Network
No full textRanking algorithms in traditional search engines are powered by enormous training data sets that are meticulously engineered and curated by a centralized entity. Decentralized peer-to-peer (p2p) networks such as torrenting applications and Web3 protocols deliberately eschew centralized databases and computational architectures when designing services and features. As such, robust search-and-rank algorithms designed for such domains must be engineered specifically for decentralized networks, and must be lightweight enough to operate on consumer-grade personal devices such as a smartphone or laptop computer. We introduce G-Rank, an unsupervised ranking algorithm designed exclusively for decentralized networks. We demonstrate that accurate, relevant ranking results can be achieved in fully decentralized networks without any centralized data aggregation, feature engineering, or model training. Furthermore, we show that such results are obtainable with minimal data preprocessing and computational overhead, and can still return highly relevant results even when a user’s device is disconnected from the network. G-Rank is highly modular in design, is not limited to categorical data, and can be implemented in a variety of domains with minimal modification. The results herein show that unsupervised ranking models designed for decentralized p2p networks are not only viable, but worthy of further research.https://github.com/awrgold/G-RankComputer Scienc
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