1,720,996 research outputs found
A high voltage olivine cathode for application in lithium-ion batteries
No full textA new olivine composition (i.e., LiFe0.25Mn0.5Co0.25PO4) is proposed as electrode material with increased energy density for application in lithium-ion batteries. The new formulation increases the working voltage and induces different electrochemical behavior with respect to bare olivine materials based on Fe. The study provides deep insight into the features of the Fe3+/Fe2+, Mn3+/Mn2+, and Co3+/Co2+ redox couples within the olivine lattice in terms of electrochemical activity, Li+ transport properties, and Li-cell behavior. The electrochemical characterization clearly reveals the voltage signatures corresponding to the various metals; however, the Mn3+/Mn2+ process has higher intrinsic polarization with respect to Fe3+/Fe2+ and Co3+/Co2+. This issue is efficiently mitigated by carbon coating the material, resulting in enhanced electrochemical performances
Silk Fibroin/Orange Peel Foam: An Efficient Biocomposite for Water Remediation
No full textA novel approach for the valorization of orange peel waste for the removal of aqueous organic pollutants is presented herein. The orange peel is combined with silk fibroin in order to obtain alcogels, which are successfully converted into highly porous biocomposite foams upon supercritical CO2 drying. The biocomposite shows a Brunauer-Emmett-Teller specific surface area of 174.45 m(2) g(-1) and can absorb three times its weight in water. The resulting adsorbents can adsorb methylene blue from water with a maximum adsorption capacity of 113.8 +/- 12.5 mg g(-1), with the orange peel activity well preserved in the polymeric matrix. The spectroscopic studies performed show that the methylene blue molecules are adsorbed in the form of monomers on the surface of the biocomposite foams, forming a monolayer as suggested by the Langmuir isotherm model. Although the agrowaste powders are already confirmed to be promising biosorbents for the removal of pollutants from water, the difficulties caused by their recovery after the water treatment may limit their manageability and applicability. With this study, such limitations can be overcome thanks to the incorporation of the powder in a solid porous system, without significantly compromising the dye adsorption capacity of the incorporated orange peel
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
CeO2 Nanoparticles-Loaded pH-Responsive Microparticles with Antitumoral Properties as Therapeutic Modulators for Osteosarcoma
Get PDFOsteosarcoma is an aggressive form of bone cancer mostly affecting young people. To date, the most effective strategy for the treatment of osteosarcoma is the surgical removal of the tumor with or without combinational chemotherapy. In this study, we present the development of a pH-sensitive drug-delivery system in the form of microparticles, with increased chemotherapeutic action against the osteosarcoma cell line SAOS-2, and with reduced toxicity against the heart myoblastic cell line H9C2. The delivery system is composed of calcium carbonate and collagen type I, and is loaded with cerium dioxide (CeO2) nanoparticles (<25 nm) and the anticancer drug doxorubicin. The fabricated microparticles were fully characterized morphologically and physicochemically, and their ability to induce or inhibit apoptosis/necrosis was assessed using in vitro functional assays and flow cytometry. The results presented in this study show that the highest concentration (250 μg/mL) of the therapeutic microparticles (CaCO3-based therapeutic modulators (C-TherMods)), which corresponds to 6.4 μg/mL of encapsulated doxorubicin, can protect the H9C2 cells even after 120 h, since the percentage of viable cells at this time point is 65%. On the contrary, when H9C2 cells are treated with 0.5 μg/mL of free doxorubicin, 75% of the cells are dead only after 24 h. When SAOS-2 cells are treated with the same concentration of C-TherMods (250 μg/mL), the viability of SAOS-2 cells is 80% after 24 h, while it reduces to 50% after 120 h. At pH 6.0, the synergic effect of the pro-oxidant CeO2nanoparticles and of the encapsulated doxorubicin leads to almost 100% of cell death, even at the lowest concentration of C-TherMods (50 μg/mL)
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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