1,720,955 research outputs found
Nanocomposite stability in Fe-, Co-, and Mn-based perovskite/spinel systems
No full textFabrication of thin film nanocomposites via decomposition and self-assembly from the vapor phase is a promising path for cost-effective fabrication of multifunctional materials. In particular, oxides as a new class of energy materials allow for rich functionalities, e. g., by combining p-and n-doped systems in catalytic or light harvesting units. Combining A-site doped perovskites ABO(3) with CoFe2O4 spinel, we have investigated thin film phase composition and nanocomposite morphology in the pseudobinary system La0.6Sr0.4BO3-CoFe2O4 for B = Fe, Co, and Mn. We observe formation of an epitaxial two-phase nanocomposite for B = Fe, i.e., the coexistence of La0.6Sr0.4FeO3 and CoFe2O4. In contrast, for B = Co or Mn nanocomposites are formed, where perovskite La0.6Sr0.4BO3 solid solutions coexists with Co-rich spinel and periclase phases. We derive conclusions for the preparation of perovskite-spinel nanocomposites with well-designed doping levels.Deutsche Forschungsgemeinschaft [JO 348/8, SFB 602
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
In Situ Electrochemical Electron Microscopy Study of Oxygen Evolution Activity of Doped Manganite Perovskites
No full textFundamental studies of catalysts based on manganese oxide compounds are of high interest since they offer the opportunity to study the role of variable valence state in the active state during O2 evolution from H2O. This paper presents a study of doping dependent O2 evolution electrocatalysis of Pr-doped CaMnO3 via in situ environmental transmission electron microscopy (ETEM) combined with ex situ cyclic voltammetry studies. ETEM studies of heterogeneous catalysis are a challenge, since the reactions in the H2O vapor phase cannot directly be observed. It is shown that the oxidation of silane by free oxygen to solid SiO2-x can be used to monitor catalytic oxygen evolution. Electron energy loss spectroscopy (EELS) as well as the in situ X-ray absorption study of near edge structures (XANES) in H2O vapor reveals that the Mn valence is decreased in the active state. Careful TEM analysis of samples measured by ex situ cyclic voltammetry and an in situ bias-controlled ETEM study allows us to distinguish between self-formation during oxygen evolution and corrosion at the Pr1-xCaxMnO3-H2O interface. Including density functional theory (DFT) calculations, trends in O2 evolution activity and defect chemistry in the active state can be correclated to doping induced changes of the electronic band structure in A-site doped manganites
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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