1,720,989 research outputs found
IONICITY OF METALLIC OXIDE SURFACES ON METALS AS OBSERVED BY AUGER (XPS) SPECTROSCOPY.
No full textResearch relevant to the understanding of polymer-metal adhesion led us to an oxygen Auger (KLL) study on metal oxide surfaces. This was done in order to analyze the ionicity and strength of 'Lewis sites' on oxide surfaces grown on metals as compared to their bulk metal oxide counterparts. Following some suggestions contained in earlier works by Wagner we show that relative Auger (KLL) oxygen energies are a sensitive probe of oxygen valence electron population and hole relaxation. A semi-empirical model is discussed to justify these findings. Furthermore it is shown that this 'observable' feature is also influenced by the metal oxide thickness at the metal surface
Adesione metallo-polimero:proprietà elettroniche e strutturali dei siti ionici in ossidi metallici superficiali e di massa
No full textIn questo contributo vengono descritte le proprietà elettroniche e strutturali dei siti ionici in ossidi metallici superficiali e di massa che influenzano le proprietà di adesione metallo-polimero
Chemical physical character of the interfaces in polymer-metal adhesion
No full textIn this contribution the chemical physical character of the interfaces in polymer-metal adhesion are discussed taking as an example the aluminium/ polyethilene interface
Thermoplastic compositions based on non-polar organic polymers and zeolites in acid form,which have strong adhesion to metals and composite objects obtainable therefrom
No full textA thermoplastic composition based on non-polar organic polymers and crystalline zeolites in acid form of which the exchangeable ions are totally or partly substituted by H+ ions, the composition having strong adhesion to metals, the invention also relating to composite objects obtainable therefrom
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
On the Electrical Properties of Polycrystalline Diamond on Silicon
No full textThe electrical behaviour of metal/diamond/silicon structures was investigated by current-voltage measurements as a function of temperature in the range 20-270 degrees C. The results were related to the morphology and composition of the diamond film by a nonlinear electrical model, taking into account both a temperature-independent conductance through highly defective regions and a temperature-dependent field-activated conductance through bulk diamond grains
A preliminary dosimetric characterization of chemical vapor deposition diamond detector prototypes in photon and electron radiotherapy beams
No full textThree radiation detectors based on polycrystalline diamond films with different thickness and resistivity,
obtained by microwave chemical vapor deposition, were tested to assess their suitability
for relative dosimetry of photon and electron beams supplied by clinical linear accelerators. All
samples showed a linear response as a function of the absorbed dose. The sensitivity per unit of
detector sensitive volume spanned between 7 and 43 nC Gy−1 mm−3 with an applied electric field of
40 kV/cm. The dose rate dependence was evaluated following the Fowler theory and D coefficient
values between 0.95 and 1.00 were found for the three samples when polarized at 40 kV/cm.
Percentage depth dose curves, output factors, and normalized dose profiles were determined for 6
and 10 MV photon beams and for 6 and 15 MeV electron beams. The results obtained with the
diamond detectors were in good agreement with those obtained by reference detector measurements
fall the data were within the experimental uncertainty of 1% s1sdg
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