1,720,958 research outputs found
Caratterizzazione delle polveri ultrafini emesse da un impianto di incenerimento di combustibile derivato dai rifiuti (CDR)
No full textNegli ultimi anni sono stati sviluppati numerosi studi epidemiologici nell’ottica di stimare gli effetti del particolato atmosferico (PM) sulla salute umana, in particolare dal punto di vista cardiovascolare e respiratorio. Particolare attenzione è stata prestata al particolato fine (PM2.5) e ultrafine (UFPs, polveri con diametro aerodinamico equivalente inferiore a 100 nm), ma non c’è unanime consenso nella comunità scientifica su quale caratteristica e/o proprietà del particolato possa causare i maggiori danni sulla salute umana. I dati storici delle emissioni evidenziano che il principale contributo in termini di particolato fine e ultrafine è dovuto alle attività antropiche, a processi industriali e al traffico veicolare. È, quindi, rilevante caratterizzare sia le sorgenti di emissione sia l’evoluzione dimensionale del particolato al fine di determinare la distribuzione di aerosol e una valutazione dell’esposizione in un’area a elevata pressione antropica.
Negli ultimi 10-15 anni si è assistito a un rapido sviluppo tecnologico nel settore dell’incenerimento dei rifiuti, grazie anche alla specifica legislazione in alcuni paesi europei che obbliga le industrie a ridurre le emissioni tossiche derivanti dagli impianti d’incenerimento cittadini (MWIs). Di conseguenza, sono utilizzate le migliori tecnologie disponibili per il trattamento delle emissioni al camino al fine di rendere questi impianti ecologicamente sostenibili. Tuttavia, ad oggi non sono stati sviluppati né specifici apparati di abbattimento di UFPs, né condotte specifiche campagne di misura e monitoraggio presso gli impianti.
Il presente lavoro descrive la campagna sperimentale volta al monitoraggio delle UFPs condotta presso l’inceneritore di CDR di San Vittore del Lazio (FR). In particolare, sono state misurate distribuzioni dimensionali e concentrazioni totali di polveri sia in emissione sia a monte del filtro a maniche. Inoltre, è stata eseguita una caratterizzazione chimica delle UFP in termini di metalli pesanti mediante la tecnica di analisi per attivazione neutronica strumentale (INAA)
ON THE CHARACTERIZATION OF ULTRAFINE PARTICLES EMITTED BY A WASTE-TO-ENERGY PLANT
No full textIn recent years, an increasing number of epidemiological studies was carried out in order to show the correlation between the particulate matter (PM) and negative health effects such as cardiovascular and breathing problems. Toxicologists have paid attention on fine (PM2.5, particulate matter with aerodynamic diameter less than 2.5 μm) and ultrafine particles (UFPs, particles with diameter less than 100 nm), but there is no consensus in the scientific community on which particle property has the worst effects on human health both in terms of size and chemical composition (organic carbon, soot, heavy metals). Emission inventories suggest that the highest contribution to the fine and UFPs come from anthropogenic activities, industrial combustion processes and traffic-related emissions. Then, it is important to characterize the emission sources as well as the evolution of particle size distribution in the proximity of these emission points in order to carried out aerosol source apportionment and exposure assessment analysis in the areas characterized by high anthropogenic pressure. In the waste management, incineration represents a favourable technique for reducing the waste volume and recovering its energy content for generating electricity and district heating. The incinerators have undergone rapid technological development over the last 10–15 years, due to specific legislation applied to industry that obliged several European countries to reduce toxic emissions from municipal waste incinerators (MWIs). In the present paper, after a brief description of the MWI examined, the results of an experimental campaign carried out in order to characterize the ultrafine particles emitted at the stack of the San Vittore del Lazio incineration plant are presented. The measurements were performed during stable combustion conditions. The particle measurements were obtained through a mobile system consisting of a Scanning Mobility Particle Sizer (SMPS 3936, TSI Inc.), a Rotating Disk Thermodiluter and Thermal Conditioner (Matter Engineering AG) as well as a home-designed sampling system. The experimental campaign was also extended in a section located before the fabric filter in order to evaluate the removal efficiency of the flue gas treatment in terms of ultrafine particles (Figure 1). Maximum values of 2.7 x107 part. cm-3 and 2x103 part. cm-3 were found for number concentration before and after the fabric filter, respectively, showing a very high efficiency in particle removing by the fabric filter
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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