1,721,232 research outputs found
Response of ceramic microbial fuel cells to direct anodic airflow and novel hydrogel cathodes
Full text link© 2019 The Authors The presence of air in the anode chamber of microbial fuel cells (MFCs)might be unavoidable in some applications. This study purposely exposed the anodic biofilm to air for sustained cycles using ceramic cylindrical MFCs. A method for improving oxygen uptake at the cathode by utilising hydrogel was also trialled. MFCs only dropped by 2 mV in response to the influx of air. At higher air-flow rates (up to 1.1 L/h)after 43–45 h, power did eventually decrease because chemical oxygen demand (COD)was being consumed (up to 96% reduction), but recovered immediately with fresh feedstock, highlighting no permanent damage to the biofilm. Two months after the application of hydrogel to the cathode chamber, MFC power increased 182%, due to better contact between cathode and ceramic surface. The results suggest a novel way of improving MFC performance using hydrogels, and demonstrates the robustness of the electro-active biofilm both during and following exposure to air
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
Small scale microbial fuel cells and different ways of reporting output
No full textThe present study, reports on the findings of connecting 2 stacks of 48 MFCs and the importance of maturity and acclimation for the anodic biofilms. Furthermore, an attempt is made to emphasize the importance of a universal unit for quantifying power output. Finally, this paper presents data from the smallest MFCs, specifically designed for wastewater treatment. The main aims of this study were to (1) configure a high number of small-scale MFCs (48) to run as a stack for a long period of time (2-years); (2) repeat this process with a new set of MFCs configured as a stack of equal dimensions (units) and compare individual as well as stack performances of both old and new MFC, through polarization experiments under identical conditions; (3) normalize and compare the recorded power output according to the plethora of methods reported in the literature; (4) design even smaller MFCs and investigate their performance.</jats:p
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
Passive feeding in paper-based microbial fuel cells
Full text linkMicrobial fuel cells (MFCs) are often constructed using materials such as plastic that can be hazardous to the environment. Building MFCs from paper is a sustainable option, making the fuel cells lightweight and easy to carry. Transported in the bottom of luggage until needed they could be used as backup power supplies in remote locations. Ideally, they would extract nutrients from the environment without extensive input from the operator, particularly if the user was injured. The current study looked at different paper MFC designs to observe whether they could produce useful power after simply being dropped onto liquid puddles containing organic matter. The results showed that both flat and 3D MFCs could generate current when dropped onto liquid without any need for physical feeding. The 3D tetrahedron MFCs generated power for over 2 weeks with the output sufficient for useful applications such as broadcasting via a transceiver
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
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