1,721,170 research outputs found
Shear and Elongational Melt Rheology of LLDPE/LDPE blends
No full textPolymer blends constitute a valuable way to produce relatively low cost new materials with properties sometimes exhibiting synergistic effects compared to those of the pure components. LLDPE/LDPE blends are widely used industrially to improve the processability of LLDPE or the elongational properties of LDPE, like melt strength. This improvements are beneficial for extrusion and film blowing processes respectively. One of the still debated open questions concerning the structure of polyethylene blends is the miscibility of the two phases, whose investigation is complicated by the identical chemical structure of the two components [1,2]. Deviations from the log-additivity rule of the newtonian viscosity are often taken as a signature of immiscibility. The reason is that theories for miscible blends, like double reptation, predict for the viscosity trends very close to this simple empirical rule. The aim of this work is to characterize the rheological behavior in shear and elongation of five series of LLDPE/LDPE blends whose parent polymers have been chosen with different viscosity and SCB content and lengt
Defining Disability in the EU Non-Discrimination Legislation: Judicial Activism and Legislative Restraints
No full textTo date EU anti-discrimination legislation, particularly the Employment Equality Directive (Directive 2000/78/EC), does not provide any clear definition of disability as a ground of discrimination. In the last few years, the Court of Justice of the European Union (CJEU) has attempted to fill this gap and discussed the concept of disability in several decisions, in the attempt to provide a definition of the ground of disability. The ratification by the European Union of the UN Convention on Rights of Persons with Disabilities (UNCRPD), has led to a clear overruling in the case law: the Court shifted from the medical model to the social model of disability. The UNCRPD now represents a milestone for the CJEU, which recognised that a duty arises to define disability in line with the social model, under the principle of consistent interpretation. Against this background, this article discusses CJEU case law, and compares and contrasts the judicial activism of the Court with the cautious approach adopted by the European Commission in the proposal for a new non-discrimination directive
Activation law parameters of viscoelastic sub-glass relaxations from dynamic mechanical moduli measurements as a function of temperature
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
Modulated excitation extended X-ray absorption fine structure spectroscopy
Full text linkThe sensitivity of extended X-ray absorption fine structure spectroscopy (EXAFS) for minute structural
changes can be enhanced by combination with the modulated excitation approach and making use of
phase sensitive analysis. A modulated EXAFS experiment of a reversible periodic Pd to PdO partial oxidation
has been simulated in order to understand the effect of the phase sensitive analysis on the shape and
meaning of the resulting phase-resolved EXAFS spectra. In particular, the simulation comprises either a
synchronous or a delayed sinusoidal variation of the EXAFS parameters, i.e. coordination number (N),
interatomic distance (R) and Debye–Waller factor (s2
), of first Pd–Pd, first Pd–O, and second Pd–(O)–Pd
coordination shells. The effect of these variations on the resulting phase-resolved Fourier transform EXAFS
spectra is discussed. The results of the simulation are validated by an in situ EXAFS experiment at the
Pd K-edge over 1.6 wt% Pd/Al2O3 undergoing reversible partial oxidation in a H2 vs. O2 modulation at 573 K.
It is shown that phase sensitive detection (PSD) is able to separate the minor contribution at ca. 2.8 Å
corresponding to the growth of the Pd–(O)–Pd shell that is otherwise hidden under the static signal of the
Pd–Pd shell of reduced Pd particles. The fitting of the phase-resolved EXAFS spectra suggests that the fast
H2 to O2 switch leads the partial oxidation of the Pd surface with the formation of a PdO shell covering a
metallic Pd core. Therefore, the dynamics of the full system can be described with greater detail than in
conventional EXAFS. The intention of this work is to provide the tools and therefore a solid guidance to
qualitatively and quantitatively understand the nature of the shape of phase-resolved FT-EXAFS spectra that
may prove helpful in the analysis of a wide range of functional materials
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