1,721,045 research outputs found
Reticulated vitreous carbon cathodes for metal ion removal from process streams
No full textReticulated vitreous carbon is a material with a high porosity [97%] and high surface area per unit volume [66 cm-1] and hence it is a good cathode material for use in metal ion recovery from aqueous solutions. Reticulated carbon cathodes have been characterised in terms of their mass transport properties by cathodic copper deposition from 0.5 mol dm-3 sodium sulphate, pH 2 solutions using a flow through electrochemical cell. Comparison of the mass transport properties have been derived from current-potential curves and from copper recovery under potentiostatic control using simple batch, batch recycle models and single pass models. Comparison of the various models showed that a simple batch approximation can satisfactorily be used to describe the metal ion decay under mass transport controlled conditions. Copper was recovered from initial cupric ion concentrations of < 10 ppm with good current efficiency, low energy consumption resulting in high space-time yield and high normalised space velocity. The effect of dissolved oxygen, chloride ion and low ionic strength electrolyte on deposition rate, current efficiency and energy consumption were also examined. Reticulated vitreous carbon cathodes were also used for selective and combined removal of metal ions from a metal ion mixture in 0.1 mol dm-3 sodium chloride, pH 7 solutions. Copper, cadmium and zinc ions were removed under potentiostatic control from initial concentrations of < 10 ppm with the effect of pH, cathode potential and possible hydroxide formation being noted. Potentiostatic reduction of cadmium and zinc from acid sulphate and lead from acid nitrate solutions were also examined along with silver ion recovery from thiosulphate based media. Finally, by use of a longer reticulated vitreous carbon cathode operating in a single pass model of operation a fractional conversion of > 99% was achieved. By segmenting this electrode into eight independent cathodes, current distributions over the length of the electrode and fractional conversions per segment were examined.</p
An Exploratory Investigation of Traditional Scoring in Diving and Relationships to the Development of Artificial Intelligence Opportunities
Get PDFThis study investigated the conceptions of perfection that figure in the minds of divers, coaches, and judges. Additionally, consideration was given to their views of whether an Artificial Intelligence (AI) based scoring system could be relied upon to yield authentic results, allied with the desirability of its use. Six participants (2 each of diver, coach, judge) were interviewed. Following verbatim transcriptions, thematic analyses were conducted to identify commonly occurring themes relevant to diving and its scoring system. The results of this preliminary study have shown a leaning towards clarification of the rules on point deductions by FINA (Fédération Internationale De Natation/ International Swimming Federation). Furthermore, the concept of perfection in diving changes from country to country and culture to culture, providing further difficulties in the objectivity of judging and there was a call for openness and clarity. With the human element of judging carrying weakness and allowing for errors, subsequently, it was felt by the respondents that some parts of a dive should be measured with technology where feasible. There was a consensus that judges could not be fully replaced without substantive changes to the sport of diving, in effect losing the artistic element that is subjectively assessed
Graduateness and sports coaching: A preliminary study of coaches’ behaviour using the revised Arizona State University Observation Instrument
Get PDFThis project aimed to identify if there were differences in coaching behaviours between coaches trained and educated in less-academic, traditional, governing body of sport approaches (n = 6) and those who were educated and trained through Higher Education routes (n = 6). Data were gathered from twelve coaches by videoing and audio-recording coaching sessions. The data were analysed using the REVISED ASUOI observation tool, employing an independent-samples t-test to establish differences between the graduate coaches and non-graduate coaches across each of the behaviour categories. Differences were identified in five categories – Learning Intention, Closed Questioning, Open Questioning, Coaches’ Model, and Observation. Graduateness as outlined by Coetzee (2014), was proffered as an explanation of differences. Further work is suggested using conversational analyses to provide a more subtle and nuanced examination of the coaches’ vocabularies and judgements as they communicate
Body size, race, and beauty in sport
Get PDFThis study investigated the attitudes of female university rugby and netball players toward their bodies, specifically their perceptions of size, race, and beauty. The sports were chosen because of their respective masculine and feminine images, historically. The study used a qualitative design. Semi-structured interviews were conducted with a sample of eight players from the women’s rugby and netball teams at a university in the north-east of England. Thematic analysis revealed three themes: inclusivity, discrimination, and the promotion of inclusiveness. Almost all participants reported negative body image, especially outside the sporting environment. However, most participants emphasised a positive outlook on their bodies in society and on the utilisation of their unique bodies to better serve their purposes in the sports they play. The study’s findings emphasise the need to foster inclusivity of body types and races in sporting environments and in the rest of society
Oral or intravenous N-acetylcysteine: which is the treatment of choice for acetaminophen (paracetamol) poisoning?
No full text© 2009 EBSCO Industries, Inc. All rights reserved.Investigates the efficacy of intravenous or oral N-acetylcysteine (NAC) in the treatment of acetaminophen poisoning. Areas of controversy surrounding the use of sulfhydryl donors for acetaminophen poisoning; Factors that may have complicated oral NAC treatment or necessitated charcoal treatment; Benefits from oral NAC.Buckley, Nicholas. Whyte, Ian. O'Connell, Dianne and Dawson, Andre
Mass transport and flow dispersion in the compartments of a modular 10 cell filter-press stack
No full textFlow dispersion, pressure drop, and averaged mass transport measurements have been made to characterize the reaction environment in an industrial scale electrochemical reactor. The 10 cell filter-press stack was operated with a relatively low mean linear velocity in the range 0.6 to 6.2 cm s–1. Flow dispersion was studied by a perturbation–response technique by electrolyte conductivity measurements at the reactor outlet. Mass transport coefficients were evaluated from the first order reaction decay of dissolved bromine (Br3–) which was anodically generated from 1 mol dm–3 NaBr (aq). Each cell consisted of two 0.72 m2 projected area electrodes separated by a cationic membrane, and each electrolyte compartment contained a high-density polyolefin turbulence promoter. The electrodes consisted of a carbon/polyethylene core with a layer of an activated carbon–poly(vinylidene difluoride) composite on each side. Comparison is made with the mass transport characteristics of a similar system that contains five bipolar cells
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
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