1,720,987 research outputs found
Optimized TiO2 blocking layer for dye-sensitized solar cells
No full textA thin compact layer of TiO2 deposited on the conductive transparent substrate of a dye-sensitized solar cell photoanode, (blocking layer, BL)
can enhance the performances of the entire device. In this paper, an optimized spin coating process using an alcoholic TiCl4 solution was
developed and correlated to the final properties of the layer. The physicochemical characteristics of the precursor solution and the spin coating
parameters were optimised to obtain a uniform layer. XRD, FE-SEM, UV–Vis spectroscopy, AFM, cyclic voltammetry and electrochemical
impedance spectroscopy were used to evaluate the influence of the number of deposition cycles on the TiO2 layer. The results were compared
with those obtained using a conventional dip coating technique, showing that the newly developed spin coating process produces blocking layers
with superior properties. Finally, analyses of the photovoltaic performances of the complete cell confirmed that an optimized blocking layer can
lead to an improvement of the solar conversion efficiency of about 84%
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
Influence of doping on the structural transformations of the proton conducting perovskite BaCe1-xYxO3-D
No full textFrom neutron diffraction it is known that the BaCeO3 perovskite undergoes a sequence of phase transformations from high temperature cubic C to rhombohedral R, to orthorhombic O1 (Imma) and to orthorhombic O2 (Pnma). Doping Y3+ on the Ce4+ site introduces charge compensating O vacancies (VO) that may be partially filled with OH complexes with exposition to H2O, so making the material an ionic conductor. Anelastic relaxation experiments have been carried out on samples doped with 2%Y and 10%Y; the real part s′(T) of the complex elastic compliance presents softenings at the transitions, and the loss s′′/s′ curves allow the content of VO and H to be monitored. Doping has a strong effect on the temperature of the Pnma/R transition: with 10%Y in the fully hydrated state TO1-R increases up to 750 K while after full outgassing falls to 500 K, meaning that the introduction of ∼5% VO shifts the transition of 250 K. While the effect of cation substitution on the transitions temperature is easily explained in terms of simple arguments usually valid for perovskites based on bond length considerations, the remarkable stabilization of the R phase by VO requires to take into account the anomalous sequence of phase transitions of undoped BaCeO3, where the R structure transforms into orthorhombic Pnma on cooling with the loss of an octahedral tilt system. © (2011) Trans Tech Publications
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
- …
