1,720,973 research outputs found
Surface Characterization of Culns(2) With Lamellar Morphology
No full textLamellar crystals of CuInS2 grown in a steep temperature gradient have been characterized. Dispersive x-ray analyses show a predominant stoichiometry Cu/In/S = 1/1/2 and inclusions of Cu deficient phases. The cleaved surface is smooth, but after chemical etching a fine structure appears, with a great number of closely packed microcrystals of a dendritic shape. X-ray diffraction spectra of lamellae only show the reflections of the CuInS2 (112) and of the CuIn5S8 (111) lattice planes, indicating a strongly oriented structure. Depth profiles of CuInS2 lamellae investigated with x-ray photoelectron spectroscopy show the presence at the cleaved surface of Cu deficient phases like CuIn5S8, which are a few tens of nanometers thick. The lamellar growth mechanism is discussed on the basis of these findings. X-ray photoelectron spectroscopy and secondary ion mass spectrometry investigations show that the oxidation behavior of the lamellar material resembles that of traditional CuInX(2) phases (X = S, Se)
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
Physicochemical characters of a ribonucleoprotein fragment extracted from rat brain, and their modification due to either enviromental or chemical influence
No full textAppropriate 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
Acetonitrile as Adsorbate or Solvent to Probe the Crystal Face Specificity of Metal-Water Interaction at Silver Electrode/Solution Interfaces
No full textThe crystal face specificity of metal–water interaction at Ag electrode/solution interfaces is investigated by using acetonitrile (ACN) as a probe molecule of the water interfacial structure or as a solvent in which water is a solute. Capacitance and voltammetric curves suggest that ACN is weakly adsorbed from aqueous solution on Ag in the order (111) > (100) > (110). Apparent inconsistencies of adsorption parameters are explained by the occurrence of two ACN adsorption modes: (i) directly on the metal surface and (ii) on the water layer adsorbed on the metal surface. Ag surface oxidation in ACN in the presence of variable amounts of water suggests that water has an inhibiting effect on Ag oxidation, the diminution of the water content in ACN leading to free anodic dissolution of the metal surface
Investigation of the oxidative-pyrolysis processes of RuCl3 center dot xH(2)O and IrCl3 center dot xH(2)O
No full textThe reactions of oxidative-thermal decomposition of the precursor salts RuCl3.xH2O and IrCl3.xH2O used in the dimensionally stable anode (DSA) preparation were studied. The pyrolytic processes were followed by secondary ion mass spectrometry (SIMS), by which it was also possible to study the deposited film structure from the depth-profiles vs. storage thickness. The mass spectra show, for both precursors, a progressive oxidation leading eventually to the formation of the respective oxides (RuO2, IrO2); by depth-profiles, however, it also was verified that the films are not homogeneous but some components are segregated in different regions
Crystal Face Specificity of Incipient Oxidation of Ag Single Crystal Electrodes in Acidic Aqueous Solution
No full textThe onset of anodic oxidation of Ag single crystal face electrodes in acidic solution is investigated by means of capacitance and voltammetric curves. The potential of incipient oxidation is found to depend only slightly on the atomic density of the surface. On the other hand, a pre-monolayer oxidation peak is identified
only for the (110) face in HClO4 while in H2SO4 it is suppressed. Results are interpreted in terms of anodic oxidation vs. anodic dissolution interference and anion adsorption vs. water oxidation competition. The behavior of the (110) face is explained on the basis of a model for water adsorption proposed for UHV experimental data. The higher reactivity of the (110) face toward water molecules supports the “hydrophilicity” scale of Ag
crystal faces based on ionic and non-ionic adsorption data
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