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    Slow pyrolysis of imperata cylindrica in a fixed bed reactor

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    Slow pyrolysis of Imperata Cylindrica has been conducted in a fixed bed reactor to determine the effect of temperature and particle sizes towards the product yield. The characterization of the Imperata Cylindrica has been analysed using several instruments such as Thermogravimetric Analysis (TGA), Carbon Hidrogen Nitrogen Sulfur and Oxygen (CHNS/O) analyzer, Bomb Calorimeter, and several analytical methods. Pyrolysis experiments were performed at temperature between 450- 600 °C, and particle sizes of 0.25-1.00 mm with constant nitrogen flow rate of 100 cm3min-1 and heating rate of 22 ºC . min-1 (slow mode). The highest liquid oil yield obtained was 20.88 % at temperature 500 °C, with particle size of 0.5-1.0 mm, and heating rate of 22 ºC . min-1. The obtained yield of liquid, solid and gas from pyrolysis were found in the range of 3.25-20.88 %, 22.63-30.50 % and 49.13-74.13 % respectively at different pyrolysis conditions. Liquid bio-oil produced from the pyrolysis of Imperata Cylindrica shows high water content in the range of 58.09- 72.74 % which was checked using Karl Fisher Titration. From Gas Chromatography- Mass Spectrometry (GC-MS), the chemical components present in the liquid oil from pyrolysis of Imperata cylindrica include acids, phenols, ketones, aldehydes, ethers, and some species of aromatics.

    Activated Carbon Derived From Pentace Triptera, Intsia Bijuga And Hevea Brasiliensis Sawdust Via Microwave-Induced Potassium Hydroxide Activation For Dyes Adsorption

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    Synthetic dyes are widely applied in various industries which has resulted in the water pollution. Therefore, this study aims to synthesis activated carbon (AC) from Pentace triptera (PS), Intsia bijuga (IS) and Hevea brasiliensis (HS) for blue (MB) and remazol brilliant violet 5R (RBV) dye adsorption via microwave-induced potassium hydroxide (KOH) activation adopted together with carbon dioxide (CO2) gasification. Optimum preparation conditions for all ACs prepared were determined using response surface methodology (RSM). ISAC showed high Bruneaur-Emmet-Teller (BET) surface area and total pore volume of 952.23 m2/g and 0.584 cm3/g, respectively compared to PSAC and HSAC. All adsorbents best fitted to the Langmuir isotherm model with ISAC showed higher maximum monolayer adsorption capacity (Qm) of 434.78 and 212.77 mg/g, respectively for MB and RBV dye at 30ºC. Kinetic studies showed that all system followed a pseudo-second order model with film diffusion was the rate-limiting step controlling adsorption. Thermodynamic studies confirmed that all systems were endothermic in nature. For the column studies, the better correlation of breakthrough data shown by Thomas and Yoon-Nelson model. The ACs had good reusability performance for MB and RBV adsorption especially up to three cycle using ethanol as solvent

    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

    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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