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Analytical methods for the determination of 137Cs and 90Sr in ash of fuel pellets used in Italy
No full textIn this study the radiological characterization of ashes of 22 different brands of wood pellets coming from different countries and used in the regions of central Italy was carried out. 137Cs and 90Sr, were found in the samples taken into account, 134Cs resulted always below the detection limit. 137Cs activity concentration ranges from 30 to 3176 Bq kg−1 (the arithmetic mean resulted to 571 Bq kg−1); 90Sr activity concentration ranges fro154.75 Bq kg−1 to 1443.70 Bq kg−1 (the arithmetic mean resulted to 684.80 Bq kg−1). The ratio of 90Sr and 137Cs activity concentration ranged from 0.22 to 40.79 showing a high variability. 77.2% of the samples show a 90Sr activity concentration higher than that of 137Cs. The concentration factors (activity concentration in ash/activity concentration in wood pellets) resulted to 222.8 and 230.0 for 137Cs and 90Sr respectively; both radionuclides are found completely in the ashes
Radioactivity in coffee
No full textThis research was dedicated to the study of the background levels of 210Po and natural gamma emitters as 40K, 214Pb, 214Bi, 228Ac, 212Pb and 212Bi in coffee powder and in coffee beverage; also the artificial 137Cs was determined. In the coffee powder the mean 210Po activity resulted 7.25 10-2 ± 2.25 10-2 Bqkg-1. 40K showed a mean activity of 907.4 ± 115.6 Bqkg-1. The mean activity concentration of 214Pb and 214Bi, indicators of 226Ra, given as mean value of the two radionuclides, resulted 10.61 ± 4.02 Bq kg-1. 228Ac, 228Ra indicator, showed a mean activity concentration of 13.73 ± 3.20 Bq kg-1. The mean activity concentration of 212Pb, 224Ra indicator, was 8.28 ± 2.88 Bq kg-1. 208Tl, 224Ra indicator, presented a mean activity concentration of 11.03 ± 4.34 Bq kg-1. In all samples, the artifical 137Cs resulted below the detection limit (2.0 Bq kg-1). The arithmetical mean value of percentage of 210Po extraction in coffee beverage resulted 20.5 ± 6.9. The percentage of transfer of gamma emitters,40K, 214Pb, 214Bi, 228Ac, 212Pb, 208Tl resulted of 80.0% %, 33.5 %, 24.7 %, 30.0 %, 35.1 %, 53.5% for 40K, 214Pb, 214Bi, 228Ac, 212Pb and 208Tl respectively
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
222Rn determination in drinkable waters of a central eastern Italian area: comparison between liquid scintillation and gamma spectrometry
No full textIt is well known that the interest in radon concentration indoor as a pollutant emerged during the energy crisis of seventies which led to reduce ventilation in dwellings. Recently the Euratom Recommendation 2001/928 suggested the necessity of performing frequent 222Rn checks on tap waters. As a consequence of this Recommendation, Urbino and Perugia Universities carried out a preliminary 222Rn determination on tap waters of the Pesaro-Urbino province. Samplings were carried out in twenty-eight sites and radon concentration was determined by liquid scintillation counting and gamma-spectrometry. The results obtained by the two techniques were comparable (the deviation from the mean is lower than 10% for 54.5% of the samples). The resulted 222Rn concentration was very low (5 Bq-·11 for 43% of the samples) and, therefore, radon in waters cannot be considered as a direct radiological risk for the local population
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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