1,720,957 research outputs found
Tetra-MnIII-containing 30-Tungsto-4-phosphate, [MnIII4 (H2O)2(P2W15O56)2]12-: Entrapped PEDOT films, surface analysis and electrochemical study
No full textA MnIII-substituted Wells-Dawson-type polyoxoanion, [MnIII 4 (H2O)2(P2W15O56)2] 12− (Mn4(P2W15)2), was surface immobilised within the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) on a glassy carbon electrode (GCE) surface. The resulting immobilised films were characterised by electrochemical techniques and subjected to a compositional and morphological characterization by means of X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), and atomic force microscopy (AFM). The redox activity of the entrapped Mn4(P2W15)2 was observed within the polymer phase. The conducting polymer films exhibited a pH-dependant redox activity associated with the polyanion Mn4(P2W15)2 and thin layer behaviour up to 100 mVs− 1 with enhanced stability towards redox cycling
Wells-Dawson type polyoxometalate, [S2W18O62]4−-doped poly(3,4-ethylenedioxythiophene) films: Voltammetric behaviour and applications to selective bromate detection
Full text linkWells-Dawson type polyoxometalate (POM) [(n-C3H7)4N]4S2W18O62 (S2W18) was successfully immobilised with a conducting polymer, poly(3,4-
ethylenedioxythiophene) (PEDOT), by chronocoulometry technique. The immobilised films with different surface thicknesses were characterised by various electrochemical techniques. The S2W18-doped PEDOT film gave four couples of redox waves, the first one corresponds to the redox process of the polymer itself and the other three couples are electron transfer at tungstate in the framework. The films exhibited inherent pH-dependent redox activity and stability of S2W18 in the thin layer up to 100 mV/s. Only slight changes were observed in the magnitude of peak currents after continuous redox cycling, indicating the relative stability of the S2W18 in the conducting PEDOT. The conductive behaviour of the film was investigated with electrochemical impedance spectroscopy. The study of electrochemical bromate ion sensing based on S2W18-doped PEDOT film employing chronoamperometric technique revealed that at an applied potential of -0.1 V, the S2W18-doped PEDOT film can detect bromate at concentrations between 100 μmol L− 1 and 2000 μmol L− 1. Moreover, the S2W18-doped PEDOT film shows a detection limit of 4 μmol L− 1 without interference from other common ions present in the water. Hybrid films exhibit significant catalytic activity with high selectivity at a low reduction potential of -0.1 V. Chemico-physical characterization of the target systems was performed using atomic force microscopy, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and Raman spectroscopy
Combining cross-reactivity of an electrode array with the selective thiol reporting process of redox indicators: targeted sensing of biothiols
No full textCombining the cross-reactivity of the voltammetric sensor array with the selective thiol reporting process of redox indicators (RIs) enables the targeted sensing of biothiols.</p
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
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
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