1,721,059 research outputs found
Low-dimensionality and epitaxial stabilization in metal supported oxide nanostructures: MnxOy on Pd(100)
No full textThis chapter presents a survey of the growth and structure of manganese oxide nanolayers on a Pd(100) substrate, investigated in two different thickness regimes through a plethora of surface science techniques (scanning tunneling microscopy, atomic force microscopy (AFM), low energy electron diffraction (LEED), SPA-LEED, X-ray photoemission spectroscopy, X-ray absorption spectroscopy (XAS), and high-resolution electron energy loss spectroscopy) and state-of-the-art theoretical tools based on density functional theory and hybrid functionals. The electronic and structural properties of the films are analyzed as a function of film thickness and growth conditions. Epitaxial (geometric) relationships that favor the growth of the different oxide phases are investigated, with special attention to the stability of the Mn3O4 (001)/MnO(001) interface and the phase stability diagram of Mn x O y /Pd(100) phases at a Mn coverage of about one monolayer. A rich variety of two-dimensional (2D) nanophases, which are novel in terms of their structural and electronic properties, have been identified, which could play an important role in mediating the epitaxial growth of MnO thicker films on Pd(100). Furthermore, the formation of O or Mn vacancies drives the transition between 2D phases with similar structural units but different lattice periodicity, indicating that ion vacancies, mixed valence states, and substoichiometry lie on the basis of the architectural flexibility in the monolayer regime. Interestingly, the latter concepts play a major role in the more complex class of functional oxides such as the manganites, of which binary manganese oxides are the simplest parent compounds
Molecular orientation of 2-mercaptobenzoxazole adsorbed on Cu(1 0 0) surface
No full textThe long range ordered p(2 × 2) self-assembled monolayer formed by dosing 2-mercaptobenzoxazole (MBO, C7H5NOS) on the Cu(1 0 0) surface at room temperature has been investigated by means of near edge X-ray adsorption fine structure (NEXAFS) technique at the sulphur K-edge. NEXAFS S–K-edge spectra have been recorded at different incident photon angles with respect to the Cu(1 0 0) surface, using linearly polarised synchrotron radiation. A clear spectral feature has been observed close to the absorption edge, with higher intensity at grazing incidence, assigned to the σ*(S–C) resonance, corresponding to the transition from the S 1s core level to the σ*(S–C) antibonding molecular state. The angular dependence of the σ*(S–C) resonance intensity clearly indicates that the S–C axis is nearly perpendicular to the surface (13° ± 13°), confirming the major role of S in bonding to the surface, and the influence of the π–π interaction between the molecules in driving the almost upright position at saturation coverage
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
ADVANCED GEOMATICS AND CONSERVATION MANAGEMENT PLAN FOR PRESERVING 20th CENTURY ARCHITECTURAL HERITAGE
Full text linkThis paper discusses the relationship between advanced geomatics and Conservation Management Plan (CMP), by deepening the case of a CMP dedicated to the conservation of the 20th century architectural heritage. A number of issues have already been discussed on how the advanced survey techniques contribute to the conservation field for the last decades (e.g. Laser Scanner, HDR, GIS, intelligence vs. abundance, B.I.M, VT/IM etc.). The authors analyse pros and cons of each technique with respect to the main purposes of a CMP: 1.knowledge, 2.value assessment, 3.data sharing and dissemination of results, 4.support for conservation and restoration activities, 5.support for the planned conservation of buildings / facility management over time. With respect to the research on the CMP for the National Art Schools of Havana, the conclusions focus on the need to share results to non-specialist stakeholders, and on the possibility to combine different scales of analysis and a plurality of buildings with various levels of interest and conservation needs
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
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