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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
Synergistic effects occurring between water-glasses and urea/ammonium dihydrogenphosphate pair for enhancing the flame retardancy of cotton
No full textCotton fabrics have been treated with two different finishing compositions based on urea (U) and ammonium dihydrogen phosphate (AP) in order to
enhance their flame retardancy properties, particularly referring to the resistance to a flame application (namely, Limiting Oxygen Index tests) and to an
irradiative heat flux of 35 kW/m2 (by cone calorimetry).
The collected results have proven a remarkable increase of cotton flame resistance: indeed, the fabrics treated with the high concentrated bath showed a LOI increase of 121 % (from 19 for neat cotton, to 42 %) and did not ignite under 35 kW/m2 heat flux. Thermogravimetry coupled with pyrolysis-combustion flow calorimetry has demonstrated efficient features of the proposed flame retardant system as char promoter for cotton. In order to reduce the amounts of U and AP employed in the selected formulations, the use of water glasses (WG) has been explored. A very low WG amount has proven to be effective in halving U and AP contents, maintaining the same fire performances already provided by the high concentrated finishing bath. Furthermore, WG have turned out to act as synergistic species as demonstrated by evaluating the synergistic effectiveness parameter
Thermal And Flame Retardant Properties of Ethylene Vinyl Acetate Copolymers Containing Deoxyribose Nucleic Acid or Ammonium Polyphosphate
No full textThe present study is aimed to compare the effect of the presence of deoxyribose nucleic acid (DNA) or ammonium polyphosphate (APP) in ethylene vinyl acetate (EVA) copolymers, as far as their thermal and flame retardant properties are considered. Indeed, although DNA has been recently discovered as a novel green flame retardant, its performances have not been compared with a conventional flame retardant such as APP yet. With this purpose, EVA compounds containing 10 or 20wt.-% of DNA or APP have been melt-blended and their thermal and flame retardant properties thoroughly investigated. The morphology of the samples has proven to be significantly different, as assessed by Scanning Electron Microscopy (SEM): indeed, APP gave rise to numerous micro-aggregates homogeneously distributed within the polymer matrix; on reverse, DNA was finely dispersed. Both the additives have favoured the char formation, inhibiting the production of volatile species, as assessed by thermogravimetry (TG) and pyrolysis-combustion flow calorimetry (PCFC). The char features of both the additives turned out to be extremely advantageous for strongly modifying the combustion behaviour of EVA, as clearly demonstrated by cone calorimetry tests
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
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