1,720,959 research outputs found

    The effects of black tea extracts on the corrosion inhibition of mild steel in acidic solution

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    It was examined to evaluate the effectiveness of extracted tea leaves as the green corrosion inhibitor that contains mild steel in acidic solvents. The test specimens were dissolved in an acidic solution with different concentrations of the extracted tea leaves. After 3 hours of immersion, the corrosion rate (CR) was measured. The results showed that a concentration of 1000 mg/l caused a significant inhibition in corrosion rate as compared to control. To see how black tea (BT) extract affected mild steel corrosion in 1 M HCl, it was subjected to a loss of weight procedure. The corrosion level and the inhibitor\u27s performance were examined at five different BT extract concentrations that included 0.4, 1, 1.4, 2, and 2.4 g/l. According to the findings, an increase in BT concentration at every temperature decreased CR. As a result of the rise in kinetic activities of the metal surface interface, typically, temperature elevation leads to an increase in CR at every concentration of BT extract. The study\u27s findings showed that adding 2.4 g/l of inhibition efficiency resulted in a temperature of 323 K, resulting in 84.95% inhibition efficiency. The small activation energy (Ea) of 8.74 and 11.45 kJ/mole reflected  the barrier layer properties of BT extract and its chemical interactions on mild steel surfaces. The thermodynamic parameter revealed the spontaneous interaction between BT extract species and steel surface as kad rose from 0.929 to 1.728 (g/l)-1

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

    Effect of low-pressure plasma treatment on the thermal behaviour of organo-modified montmorillonite nanoclay

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    The thermal behaviour of nanoclay can be considered an important factor in obtaining high-performance polymer nanocomposite. Thus, the current study aims to investigate the effect of plasma treatment on the thermal stability of two organically modified nanoclays, Cloisite 30B (C30B) and Nanomer I.34TCN (I.34TCN), compared with pristine NaMMT.The nanoclays were studied and characterised using Thermogravimetric Analysis (TGA). TGA was used to measure the weight loss of the plasma-treated and untreated nanoclays (C30B, I.34TCN, and NaMMT nanoclays) over a 30-630 C temperature range.Based on TGA results, the decomposition of all plasma-treated nano clays (C30B, I.34TCN and pristine NaMMT) was shifted to a lower temperature than in the untreated ones at all those stages. Thus, plasma treatment was successfully used as a convenient method to alter the chemical structure and surface morphology of MMT nanoclays for better thermal behaviour and filling distribution.This hypothesis can be corroborated by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) for a better understanding of the structural and surface changes that occurred due to the plasma action, which can provide an interpretation of the changes in the thermal behaviour of nanoclays.The plasma treatment, therefore, can improve the thermal stabilisation of the nanocomposite powders for the LS fabricated parts and even for the surrounding powder for the recovery process. Plasma-treated nano clay, therefore, can be used to reinforce polymers with an expectation of increasing the thermal stability of the resultant composites. Thus, the plasma-treated composite can be fabricated for laser sintering applications in fields that require high thermal stability.The surface modification of nanoclay powders via plasma treatment can be used as a convenient method to alter the chemical structure and surface morphology for better thermal behaviour and filling distribution

    Dispelling the Myths Behind First-author Citation Counts

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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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