1,720,972 research outputs found
Catalytic co-pyrolysis of keyboard plastic and sawdust toward petrochemical-grade hydrocarbons over niobium-loaded zeolite catalyst
No full textThis study examines for the first-time the in-situ co-pyrolysis of e-waste plastic, keyboards (KB) and sawdust (SD) in different blending ratios (2/1, 1/1, and 1/2) using a tandem microreactor-gas chromatography/mass spectrometry system at 600 degrees C. The blend with SD/KB = 2/1 exhibited a positive synergistic effect in the fractionation of the components and production of valuable aromatics, such as benzene, toluene, ethylbenzene, xylene (BTEX), with a significant lowering of oxygenates. For the catalytic co-pyrolysis, H beta(25) exhibited prominent results toward the BTEX production compared to HZSM-5(30) and H beta(38). Among the metal-loaded (Nb, Zn, and Fe) H beta(25), the maximum amount of BTEX was determined over Nb/H beta(25) with catalyst/feedstock = 3/1. The results of the ex-situ micropyrolyzer configuration highlighted the prominent significance of the in-situ mode toward the activation in breaking the KB polymeric structure. Moreover, the lab-scale co-pyrolysis results exhibited a maximum positive synergistic effect (21.54 %) in the quantified yield of BTEX over the Nb/H beta(25) catalyst. Furthermore, the Nb/H beta(25) catalyst was also subjected to the three lab-scale catalytic co-pyrolysis cycles to evaluate its structural stability and durability.
Design and thermal performance investigation of a box cooker with flexible solar collector tubes: An experimental research
No full textKumar, Avnish/0000-0002-8843-1643; Saxena, Abhishek/0000-0001-9253-6774In recent years, solar cookers have been technologically promoted by most of the national governments as renewable and sustainable cooking system round the globe. in the present article, a solar box cooker (SBC) has been developed for fast response and uninterrupted cooking process. For this purpose, a cylindrical copper tube infused with thermal energy storage (TES) has been designed and tested under a modified SBC. Experimental study has been carried out on three different TES materials such as; grainy carbon powder, paraffin wax and specific mixture of carbon powder and paraffin. Specifically, twelve TES filled tubes have been brought into the use for experimentation at three different configurations. Results indicate that the modified cooker has better performance in terms of efficiency (53.81%), overall heat loss coefficient (5.11 W/m(2)degrees C), cooking power (68.81 W) and heat transfer coefficient (56.78 W/m(2)degrees C) in comparison with a conventional SBC and other designs using different TES materials. PCM infused tubes are low in cost and flexible to carry with SBC for outdoor cooking. It can easily be carried anywhere along with cooker. This novel configuration enables a fast response cooking with an enhanced efficiency irrespective of climatic conditions. the total cost of SBC is estimated about $39.11. (C) 2020 Elsevier Ltd. All rights reserved
Improvement in the production of aromatics from pyrolysis of plastic waste over Ga-modified ZSM-5 catalyst under C1-gas environment
No full textThis study explores, for the first time, the influence of various C1 gases, such as methane (CH4), carbon dioxide (CO2), and biogas (CH4 + CO2), on catalytic pyrolysis of plastic waste (polypropylene) to evaluate their potential in producing aromatic hydrocarbons. Also, this study used the 0.5 wt%, 1 wt%, 3 wt%, and 5 wt% Ga-modified ZSM-5 catalyst and its reduction-oxidation processed catalysts owing to their promising catalytic properties. According to the results, the highest yield (39.5 wt%) of BTEX (benzene, toluene, xylene, and ethylbenzene) was achieved under CH4 over RO-GHZ(1) catalyst among all tested conditions. The reduction-oxidation process not only promotes a significant reduction of the Ga-size but also induces its diffusion inside the pore, compared to GHZ(1). This leads to the formation of highly active GaO+ ionic species, balancing the Lewis/Br & ouml;nsted ratio, thereby accelerating the aromatization reaction. The effect of Ga loading on the RO-GHZ catalyst was also evaluated systematically, which showed a negative impact on the BTEX yield owing to the lowering in the concentration of active GaO+ species. A detailed catalyst characterization supports the experimental results well. (c) 2025, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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