1,720,960 research outputs found
Non-stoichiometric molybdenum oxides as cathodes for lithium cells: Part I. Primary batteries
No full textSome non-stoichiometric Mo oxides have been tested as cathodes for primary Li cells. Their performance has been evaluated as a function of current density, electrolyte, temperature, cathode porosity and formulation. Specific capacities exceeding 0.4·Ah g−1 could be reached at low rates. As found with MoO3, these oxides give rise to the formation of ternary phases of the type LimyMomO3m−1. Li+ insertion in the lattices allows structure retention for Li/Mo ratios lower than 0.7–0.8, whereas higher Li+ contents result in the appearance of new phases
On the possibility of using silver salts other than Ag2CrO4 in organic lithium cells
No full textSeveral silver salts, including compounds listed in the literature and new compounds, have been examined to ascertain if their performances as cathodes for lithium cells could exceed that of Ag2CrO4. Discharges at various rates, polarization and cyclic voltammetry experiments were used to characterize their behaviour. Coulombic and X-ray analysis have enabled information to be obtained on the discharge reactions but the reductions of the anions still have uncertain features. Of the compounds examined, Ag4P2O7 is the most promising one, especially by virtue of a higher load voltage. Ag5IO6 and AgIO3, at low rates, and AgIO4, at high rates, also approach the performance of Ag2 CrO4
Non-stoichiometric molybdenum oxides as cathodes for lithium cells: Part III. cells based on Mo18O52
No full textThe non-stoichiometric Mo18O52 oxide, based on the MoO3 structure, was tested as a cathode material in both primary and secondary Li cells. It may intercalate reversibly in its layered structure up to 1.2 Li/Mo (at 0.5–1.0 mA cm−2), so forming ternary phases.
In the solid matrix Li+ ion diffusion is relatively fast (D≈10−9 cm2 s−1) and gives rise to a structure in which Li+ is tetrahedrally coordinated by oxygen. This oxide shows a high rate capability and can also act as a cathode material for secondary batteries in the low-rate range. The resemblance to the parent oxide MoO3 is obviously marked but differences were found with regard to the effect of additives and to the recharge efficiency, due to some structural difference
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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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