1,720,984 research outputs found
Electrochemical polishing of boron-doped diamond in organic media
No full textThe electropolishing of a boron-doped diamond ~BDD! film deposited by chemical vapor deposition has been studied in acetic acid-H2SO4 media. The electropolished surface has been characterized by scanning electron microscopy ~SEM!, X-ray photoelectron spectroscopy ~XPS!, and electrochemical measurements. The results have shown that in 1 M H2SO4 no polishing of the surface occurred even after prolonged time; on the contrary, in electrolyte containing 3 M acetic acid in 1 M H2SO4 the morphology changed rapidly. The surface became smoother and the roughness decreased as the typical results of a polishing process. All the non-diamond impurities were also removed by the electropolishing treatment in acetic acid media
DSA-type anode based on conductive porous p-silicon substrate
No full textPorous silicon (PS) thin films have been prepared by electrochemical anodization of p-Si in HF–H2O–EtOH solution and they have been used as substrate material for the preparation of iridium oxide based electrodes (PS/IrO2) using the thermal decomposition technique. The morphology and the electrochemical behaviour of the PS/IrO2 have been studied and the results have been compared with IrO2 electrodes deposited on a sandblasted p-silicon (p-Si/IrO2). SEM analyses have revealed that the PS/IrO2 electrodes are porous, rough and IrO2 appears to be deposited within some silicon pores, while the p-Si/IrO2 present a _mud-cracked_ surface. Cyclic voltammetries in 1 M HClO4 have shown that the PS/IrO2 presents higher surface area than p-Si/IrO2
Electrochemical behaviour of fluorinated boron-doped diamond
No full textThe surface properties and the electrochemical behavior of a fluorinated boron-doped diamond ~F-BDD! electrode prepared by plasma treatment in CF4-He mixture has been studied by X-ray photoelectron spectroscopy and cyclic voltammetry in acidic media. The results have shown the presence of carbon-fluorine bonding ~C—CF and C—F! on the surface of F-BDD, which made the surface more hydrophobic. It was also found that hydrogen evolution was shifted to more cathodic potentials for fluorinated diamond, as compared with untreated BDD. Finally, the higher cathodic overpotential for hydrogen evolution permitted nickel deposition and nitrate reduction
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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