1,721,059 research outputs found
Materials and techniques of Art Nouveau architecture in Italy and Portugal: a first insight for an European route to consistent restoration
Full text linkThe results of the investigations on building materials and techniques of Casa Major Pessoa, a typical Art
Nouveau construction in Aveiro (Portugal), and two coeval Art Nouveau buildings in Bologna (Italy) are presented
as a methodological contribution to the restoration of this kind of buildings. This is the first step to
ascertain the existence of a common thread between local materials, technologies and architecture in European
countries at the same period. A holistic approach was adopted: materials were investigated along with
architectural, structural and technological features, in order to achieve a first insight into the Art Nouveau
architecture in Europe in particular for its consistent restoration without loss of historical memory
Structural studies and electrical properties of recycled glasses from glass and incinerator wastes
No full textThe electrical behaviour of different glass compositions obtained from mixing waste glass deriving from a community glass recycling program and silicate waste from the incineration of municipal solid residues (from Reggio Emilia city) have been investigated as a function of temperature and frequency. The electrical and dielectric properties were related to structural studies performed on the same glassy materials. As the amount of incinerator wastes increases, on account of lower alkali and higher alkaline-earth content in the final glass composition, conductivity and dielectric losses decrease approaching the behaviour of type E glass fibres, so envisaging a possible use of waste-containing glasses in the production of high voltage insulators
New hybrid nanocomposites based on commercial organophilic clay and poly(styrene-b-butadiene) copolymer
No full textThe preparation, by direct melt intercalation, and the properties of new hybrid organic-inorganic nanocomposites, consisting of a commercial sample of poly(styrene-b-butadiene) copolymer (SBS) and a commercial organophilic clay containing the dioctadecyl dimethyl ammonium salt are described. In addition, several mixtures between the same copolymer and an unfunctionalized clay were prepared and studied. XRD spectra showed a partial insertion of the SBS block copolymer segments in the interlayers of the organophilic clay, accompanied by a loss of correlation within the layers. The degree of insertion increased by annealing the nanocomposites at 120 degrees C for increasing time periods. No interaction between the polymer matrix and the unfunctionalized clay was found. The storage modulus value, in the plateau region between the glass transition processes of the polybutadiene and the polystyrene blocks, and the glass transition temperature of the polystyrene block domain increase as both the organophilic clay content and the annealing time increase. The glass transition process of the polybutadiene block domain is practically unaffected by the filler content and the annealing treatments, These data are most promising for upgrading the thermo-mechanical behavior and the application temperature window of the SBS thermoplastic elastomers through the preparation of nanocomposites employing suitably designed organophilic clays
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
Synthesis, thermal and electrical characterization of 2-methylpentane-1,5- diammonium tetrachlorocadmate(II) with perovskite-like structure
No full textThis paper reports the synthesis and the structural, thermal and electrical characterization of the 2-methyl-pentane-1,5-diammonium bidimensional chlorocadmate(II) system with perovskite-like structure. Its structure consists of layers of CdCl6 corner-sharing octahedra extending in the ab plane. Interposed sheets of organic dications link adjacent layers through hydrogen bonding and contribute to the crystal packing. The presence of a methyl group on the C(4) atom of the organic chain is considered responsible for the thermal stability of the compound between room and melting temperature (605 K). The compound behaves as an electrical insulator at low temperature approaching semiconducting values at higher temperature. These results are also compared with those found for other structurally similar compounds
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