1,721,057 research outputs found
Influence of rare earth metals addition on the corrosion behaviour of copper in alkaline environment
No full textMicrostructural characterization and corrosion behavior of lead, bismuth and antimony tellurides prepared by melting
No full textThe corrosion behavior of lead, bismuth and antimony tellurides (PbTe, Bi2Te3 and Sb2Te3) was investi- gated in naturally aerated 0.1 M NaCl solution by open circuit potential and impedance spectroscopy measurements. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS) were used to characterize the samples prior to and after the electrochemical tests. All the investigated tellurides exhibit a one-phase microstructure, as evidenced by SEM characterization. The electrochemical results showed that in sodium chloride solution the corrosion resistance of the PbTe intermetallic com- pound was higher than that of bismuth and antimony tellurides owing to a more stable corrosion prod- ucts laye
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
Musei e laboratori: un lavoro comune per la salvaguardia delle tartarughe marine
No full textWe describe the aim, flowchart and current state of a research consisting in the collection, classification and conservation of alive and dead individuals of marine turtles found stranded along the Latium coasts. Since its inclusion in the Centro Studi Cetacei e Tartarughe marine (1997), 140 records were collected by the Civic Museum of Zoology, Rome. The osteological collection hosts material dating since the end of the 19th century. DNA obtained from both stranded and museum specimens revealed the mitochondrial haplotype CC-A2 as the most common. The results of the entire study will be disseminated in the Museum and made publicly available through its website. The relevance of the present work consists in highlighting the close relationship among institutions involved in recovery, rescue and rehabilitation, classification and exhibition, DNA studies and dissemination. The main purpose is to inform about the relevance of non-invasive genetic analyses of dead animals for the understanding of the biology of endangered species. An added value of this research is to made available to a wide audience scientific information currently accessible only to the researchers.Si descrive lo scopo, il programma e lo stato di avanzamento della raccolta, sistematizzazione, classificazione e conservazione degli esemplari di tartaruga marina spiaggiati lungo le coste del Lazio, sia vivi che morti. Dall’inizio della sua inclusione nella rete del Centro Studi Cetacei e Tartarughe marine (1997), il Museo Civico di Zoologia di Roma ha ricevuto complessivamente 140 segnalazioni. La collezione osteologica raccoglie reperti a partire dalla fine dell’800. L’analisi del DNA da animali spiaggiati e in collezione ha rivelato che l’aplotipo mitocondriale CC-A2 è quello maggiormente rappresentato. I risultati dell’intero studio sono destinati ad essere diffusi inizialmente all’interno del Museo e resi disponibili tramite il suo sito web. L’importanza del lavoro qui descritto sta nel rendere esplicita la stretta interdipendenza e collaborazione tra le strutture che drenano le segnalazioni, quelle che trattano gli esemplari vivi o morti, quelle che provvedono alla conservazione e catalogazione dei reperti, quelle competenti per le analisi genetiche, e quelle che hanno la missione di trasferire i risultati al grande pubblico, chiarendo come l’analisi genetica non-invasiva di reperti museali e di animali ormai morti sia rilevante per la protezione di una specie in declino, e valorizzando allo stesso tempo un patrimonio attualmente accessibile solo a specialisti
Diffusione della Biologia della Conservazione: un rendiconto scientifico sul monitoraggio, la genetica e la conservazione delle tartarughe marine
No full textVariations 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
Interfacial reactivity of the filled skutterudite smy(Fexni1−x)4sb12 in contact with liquid in-based alloys and sn
No full textThe study of the wettability of thermoelectric materials, as well as the search for the most proper brazing alloys, is of the maximum importance to get one step closer to the realization of a thermoelectric device. In this work, a wettability study of the filled skutterudite Smy(FexNi1−x)4Sb12 by Sn and In-based alloys is presented. Samples, having both p- and n- characters were prepared by the conventional melting-quenching-annealing technique and subsequently densified by spark plasma sintering (SPS). Afterward, wettability tests were performed by the sessile drop method at 773 K for 20 min. Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) analyses performed on the cross-section of the solidified drops suggest quite a complicated scenario due to the coexistence and the interaction of a large number of different elements in each analyzed system. Indeed, the indication of a strong reaction of In-based alloys with skutterudite, accompanied by the formation of the InSb intermetallic compound, is clear; on the contrary, Sn exhibits a milder reactivity, and thus, a more promising behavior, being its appreciable wettability, whilst coupled to a limited reactivity
Effect of silicon and germanium alloying additions on the passivationcharacteristics of Fe3 Al intermetallic in sulphuric acid solution
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