1,720,956 research outputs found
Removal of hydrocarbons from contaminated soils by using a thermally expanded graphite sorbent
No full textLab-scale experiments on three soil matrices featured by increasing granulometry (sea sand, silica sand and gravel) were carried out in order to evaluate the adsorption capability and the removal efficiency of a new graphene-based material.
Soil samples, firstly contaminated with different quantities of used lubricant oil up to final concentrations of 12.5, 25.0, 50.0 g kg-1, were treated with an opportune amount of thermally expanded graphite (TEG) (i.e. 1/10, 1/20, 1/40 as TEG/pollutant ratio).
Results show that the removal efficiency of TEG is directly correlated to the contamination level of the soil. The best removal efficiency (87.04%) was obtained during the treatment of gravel samples at the maximum contamination level by using the highest dosage of TEG. A good removal efficiency (80.83%) was also achieved using lower TEG/pollutant ratio. Moreover, TEG at ratio 1/10 showed worse removal efficiencies in treating sea (81.17%) and silica sand (63.52%) than gravel.
In this study, also the thermal regeneration was investigated in order to evaluate a possible reuse of TEG with subsequent technical and economic advantages. TEG-technique proves to be technologically and economically competitive with other currently used technologies, revealing the best choice for the remediation of hydrocarbon-contaminated soils
Lab-scale investigation on remediation of sediments contaminated with hydrocarbons by using super-expanded graphite
No full textIn view of necessity to develop simple, rapid, and efficient
methods for monitoring and removal contaminants from
soil, a new graphene-based material is presented for
treatment of hydrocarbon-contaminated soils. Lab-scale
experiments on three soil matrices featured by increasing
granulometry were carried to evaluate graphene adsorption
capability, as removal efficiency. Soil samples, firstly
contaminated with different quantities of mineral
exhausted oil up to final concentrations of 12500, 25000,
50000 mgkg-1, respectively, were treated with opportune
amount of graphene. Results show as the removal
efficiency of graphene is directly proportional to
contamination level of the soil. Particularly, the best
removal efficiency (87.04%) was reached during treatment
of gravel samples at maximum contamination level using
the highest dosage of graphene, even though good results
(80.83%) were also achieved using lower
graphene/pollutant ratio. Moreover, graphene at ratio 1/10
showed worse removal efficiencies in treating sea
(81.17%) and silica sand (63.52%) than gravel. In this
study, also the thermal regeneration was investigated in
order to evaluate a possible reuse of graphene with
subsequent technical and economic advantages. Graphenetechnique
proves to be technologically and economically
competitive with other currently used technologies,
revealing the best choice for the remediation of
hydrocarbon-contaminated soils
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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