1,720,958 research outputs found
A review of the degradation mechanisms of NCM cathodes and corresponding mitigation strategies
Get PDFLi-ion batteries (LIBs) are the most widely used form of energy storage in
mobile electronic devices and electric vehicles. Li-ion battery cathodes with
the composition LiNixMnyCozO2 (NCMs) currently display some of the most
promising electrochemical characteristics for high performance LIBs. NCM
compositions with high nickel content (x > 0.8) exhibit the largest specific
capacity while undergoing fast degradation and presenting safety issues. As the
main degradation mechanisms of NCM materials and the mitigation of their
degradation, are still subjects of many ongoing studies, this work summarizes
the current knowledge on the subject. Here, the existing literature is reviewed
to present the structural and electrochemical degradation of NCM with varying
Ni stoichiometries (NCM111, NCM622, NCM811, and beyond). Routes for hindering
the degradation of NCM are discussed as a function of Ni content in NCM and
include doping, application of protective coatings, and engineering of the
microstructure. A comprehensive understanding of the main degradation pathways
of NCM is key to applying the most appropriate mitigation strategies and keep
advancing towards higher energy NCM materials with longer cycle-life.Comment: Accepted manuscript, 94 pages, 12 figures, 1 tabl
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
Experimental Confirmation of C-Rate Dependent Minima Shifts in Arrhenius Plots of Li-Ion Battery Aging
Get PDFThe part of the research performed at ZSW was carried out in the framework of the industrial collective research program (IGF no. 20884 N/2). It was supported by the Federal Ministry for Economic Affairs and Climate Action (BMWK) through the AiF (German Federation of Industrial Research Associations eV) based on a decision taken by the German Bundestag. G.K. acknowledges funding from the Latvian Council of Science (lzp-2020/1-0425) and from the European Union’s Horizon 2020 Framework Program under grant agreement No. 739508, project CAMART2.Li-ion batteries show a minimum of their aging rate at a certain temperature. This minimum in the corresponding Arrhenius plot expresses the longest cycle life at a certain C-rate. By characterizing aging of laboratory-made pouch cells and commercial 21700 cells as a function of C-rate and ambient temperature, we confirm that this minimum indeed shifts with the charging C-rate. Increasing C-rates lead to higher optimal ambient temperatures with respect to the aging rate. The differences between both cell types are discussed regarding the specific energy and anode coating thickness of the tested cells. © 2022 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. [DOI: 10.1149/1945-7111/ac580d].IGF no. 20884 N/2; Latvian Council of Science (lzp-2020/1-0425); European Union’s Horizon 2020 Framework Program under grant agreement No. 739508, project CAMART2
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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