1,720,954 research outputs found
Optimization of Bio-lubricant Produced from Non-edible Jatropha curcas Seed Oil
Get PDFAbstract. This paper presents the production and optimization of a bio-lubricant derived from non-edible Jatropha plant seed oil. Plant oil-based lubricants offer significant environmental benefits and are derived from renewable sources, making them an attractive alternative to conventional lubricants. They provide a potential solution for sustainable and low-cost feedstock for fuel oil and its derivatives without competing with food uses, as Jatropha oil contains toxic esters unsuitable for human consumption. Jatropha seed oil was extracted using a Soxhlet apparatus fitted with a heating mantle. A total of 500 g of the extracted oil was esterified in a round-bottom flask glass reactor with 25 wt% methanol and 1.0 wt% H₂SO₄ as a catalyst, reducing free fatty acids (FFA) to approximately 1%. The esterified oil was then subjected to transesterification in a reactor preheated to 60°C. A mixture of 1.0 wt% NaOH and methanol at a 6:1 ratio was added while stirring at 300 rpm for a reaction time of 90 minutes. The transesterification process was optimized using a 23 response surface methodology (RSM) experimental design. This design evaluated the effects of temperature (112.16°C to 160.00°C), reaction time (1.81 to 5.00 hours), and catalyst concentration (0.73% to 1.73% w/w) at a constant mole ratio of JME to TMP of 3.9:1 under vacuum conditions. The results revealed that the optimal conditions for bio-lubricant synthesis were a temperature of 130°C, a reaction time of 3 hours, and a catalyst concentration of 0.8% w/w. A second-order quadratic model was developed to predict the yield of Jatropha curcas bio lubricant based on the process variables. The model predicted a yield of 88.74% with a desirability of 0.9739 and demonstrated a high coefficient of determination (R²) of 0.9739, indicating strong predictive accuracy Keywords:Bio-lubricant, Jatropha, Esterification, Seed Oi
Hetero-Alkali Catalyst for Production of Biodiesel from Domesticated Waste: (Used Waste oil)
Get PDFBiodiesel, a fuel derived from renewable sources, has garnered significant attention from energy researchers over the past two decades as a clean alternative to diesel fuel. This increased interest can be attributed to the alarming impact of climate change caused by the use of traditional diesel fuel. This paper focuses on showcasing the qualities of biodiesel produced from used waste oil and the positive impact on the alarming change in climate today. The observable characteristics of used waste oil for the synthesis of biodiesel in the presence of an ethanolic CaO-K2 O-SiO2 base catalyst created from leftover palm kernel empty bunches was rigorously explored in this study. The catalyst obtained from Palm Kernel Bunch Stem (PKBS) was characterized using Scanning Electron Microscope (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), Extended RangeSpectroscopy - Flame Photometry (XRS-FP), Brunauer-Emmett-Teller analyzer (BET) isothermal adsorption and qualitative analysis. Reusability of catalyst and economic evaluation of the synthesized biodiesel were also evaluated. The quality of the Oil was identified through standard techniques by examining its physicochemical characteristics as well as other elements. According to the findings, the improved Used Waste Oil (UWO) characteristics met the specifications for oil required to produce biodiesel. The Used Waste Oil’s physicochemical properties included the oil’s physical condition as liquid/dark brownish at 28, acid value of 0.96 (mg KOH/g oil), FFA (% oleic acid), 0.48, iodine value of 152.00 (I2g/100g), and peroxide value of 5.1 milli-equivalent of peroxide/kg of oil, among others. The obtained catalyst demonstrated high basic strength with potassium oxide (61.63 wt/%) being the predominant component. At run 5 with 98.52 (%wt /wt), 65 minutes reaction time, 4.0 (%wt) catalyst amount, reaction temperature of 70 , and a 7:1 ethanol to oil ratio produced the highest biodiesel yield. The study concluded that, UWO can possibly be utilized as an economically benign feedstock for the production of biodiesel, and the resultant catalyst could potentially be employed in industries as bio-base
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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