1,720,970 research outputs found
Emigrazione e rimesse: gestione patrimoniale e strategie familiari nel Mezzogiorno italiano tra Otto e Novecento, in T. Bechini, C. Brice (a cura di), I beni dei migranti. Patrimoni e mobilità nel lungo Ottocento in Italia, Viella, Roma 2024.
No full textStudies on the transition metal catalyzed synthesis of variously substituted (E)-3-[1-(aryl)methylidene]- and (E)-3-(1-alkylidene)-3H-furan-2-ones
No full text5-Aryl and 5-alkyl substituted (E)-3-[1-(aryl)methylidene]- and (E)-3-(1-alkylidene)-3H-furan-2-ones, (E)-9, have been selectively synthesized by cyclization of the corresponding (E)-2-(1-alkynyl)-3-aryl/alkylpropenoic acids, (E)-11, in the presence of AgNO(3) or Pd-catalysts such as trans-di(mu-acetato)bis[(di-o-tolylphosphino)benzyl] or that constituted of a mixture of Et(3)N and PdCl(2)(PhCN)(2) or PdCl(2)(CH(3)CN)(2). in a 3 : 1 molar ratio, respectively. A representative (E)-5-aryl-3-[1-(aryl)methylidene]-3H-furan-2-one, i.e. (E)-9i, has been also prepared by a tandem process involving a Pd(0)- and Cu(I)-catalyzed cross-coupling reaction between an 1-alkyne and a (Z)-3-aryl-2-bromopropenoic acid followed by a catalytic innamolecular oxypalladation of the resulting cross-coupled product. However, when this same approach was used to prepare an (E)-5-alkyl-3-[1-(aryl)methylidene]-3H-furan-2-one, i.e. (E)-9j, a mixture of (E)-9j and the corresponding (E)/(Z)-5-(1-alkylidene)-3-(aryl)methyl-5H-furan-2-one, i.e. (E)/(Z)-20, was obtained. Finally, in an attempt to prepare an (E)-4-alkyl-5-aryl-3-[1-(aryl)methylidene]-3H-furan-2-one, i.e. (E)-14a, by a tandem process involving the intramolecular oxypalladation of an (E)-enynoic acid, (E)-11, followed by a cross-coupling reaction of the resulting compound with an aryl iodide, a (Z)-5-(1-alkynyl)-4-aryl-3-arylmethyl-5H-furan-2-one, i.e. (Z)-22, has been stereoselectively obtained. (C) 1997 Elsevier Science Ltd. All rights reserved
Performance qualification of a HEPA filter at high temperature
No full textThe authors propose a method for the control of the filtering characteristics of high-efficiency particulate air (HEPA) filters set up in the sterilization tunnels at a temperature of 300°C and beyond, corresponding to the operating conditions. In the present work the HEPA filter efficiency has been evaluated both with oily aerosol of bis(2-ethylhexyl)sebacate and with pre-calibrated barium sulphate particles. The former was used at room temperature, while for the latter also the working temperature of the sterilization tunnel was employed. Furthermore, attention was given to the airborne particulate cleanliness classes of the filtering characteristics of HEPA filters at high temperature. The results obtained in the present investigation confirm the practicability of our method to evaluate the filtering characteristics at the working conditions, primarily during the performance qualification steps
Nouvelle approche de la validation d'un tunnel de sterilisation a flux laminaire: efficacite du systeme filtrant a chaud
No full text
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
- …
