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Pyrolysis in indirectly heated fixed bed with internals: The first application to oil shale
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The indirectly heated fixed bed reactor with particularly designed internals has been devised to achieve advanced pyrolysis performance for coal (Energy & Fuels, 28,2014: 236-244). This study extends the application of the reactor to oil shale and thereby solves the problems of low shale oil yield and low heating efficiency to shale particles in conventional fixed beds. The yield and quality of the produced shale oil and the rate heating the oil shale particles were compared for laboratory fixed beds without and with the particularly designed internals. It was shown that the use of internals doubled the efficiency of heating the oil shale inside the reactor from the heated reactor wall. Raising the heating temperature from 600 degrees C to 1000 degrees C increased the shale oil yield from 9.50% to 10.60% in the bed with internals, and reached 84.9% of the oil yield of Fischer assay (12.49 wt.% in dry base). Furthermore, the shale oil maintained its relatively stable aliphatic hydrocarbon content. In the bed without any internals such a temperature rise sharply decreased the shale oil yield from 9.53% to 4.60%. Consequently, the fixed bed with internals would be an advanced reactor also for oil shale pyrolysis, which allows high process efficiency, high oil yield and high oil quality. (C) 2015 Elsevier B.V. All rights reserved.</p
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
Oil shale pyrolysis in indirectly heated fixed bed with internals under reduced pressure
No full textOur previous studies have shown evident technical superiorities of oil shale pyrolysis in a newly devised fixed bed reactor with particularly designed internals (Fuel Processing Technology, 138, 2015: 147-155). This study is furthered to optimize the operating conditions by focusing on the reaction pressure to enhance the yield and quality of shale oil in the fixed bed reactor with internals. Reducing the pyrolysis pressure increased the shale oil yield in comparison with the pyrolysis under atmospheric pressure. This influence due to reducing reaction pressure appeared to be higher in the reactor with internals than in the reactor without any internals. Moreover, there were higher yield of aliphatic components and fewer aromatic species in the reactor with internals, essentially indicating the suppressed secondary reactions to the produced primary shale oil in the new reactor. In this reactor the shale oil yield reached 97.57% of the Fisher Assay yield (8.24 wt.% dry basis) at a furnace heating temperature of 1000 degrees C under reduced pressure conditions. Consequently, there is actually some synergistic effect between internals and reducing pressure so that adopting internals and using vacuum condition can grant the indirectly heated fixed bed reactor great potential to achieve high yield and high quality of shale oil in oil shale pyrolysis. (C) 2016 Elsevier B.V. All rights reserved
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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