1,721,144 research outputs found
Paradossi del comico. Da Riccoboni a Goldoni
No full textIl contributo analizza e classifica varie tipologie delle definizione teoriche del comico nel Settecento italiano, evidenziando l'affermarsi del comico serio da Riccoboni a Goldoni ad Albergat
The surface triplet exciton of C60(111)
No full textThe electron energy loss spectrum of the triplet exciton of [111] oriented C60 films has been measured as a function of temperature, film thickness and primary electron energy. The triplet exciton of the [111] surface is found at 1.549 eV and that of the bulk at 1.64 eV. The vibrational structure of the spectrum is in agreement with the T2g symmetry of the electronic wavefunction and with the molecular distortion of the excited state predicted by calculations
First-order orientational-disordering transition on the (111) surface of C60
No full textThe temperature dependences of the triplet exciton, of the vibrational modes, and of the low-energy diffraction pattern of the (111) surface of well-ordered C60 films indicate that this surface undergoes a first-order orientational order-disorder phase transition at 225±3 K, well below the temperature of the corresponding phase transition in the bulk of the same samples, which we find to be 260 K. The bulk phase transition is therefore initiated by the surface. To our knowledge, this is the first example of a surface orientational phase transition, a phenomenon that should occur on several other molecular crystal surface
Chemisorption and fragmentation of C60 on Pt(111) and Ni(110)
No full textThe interaction between C60 and the Pt(111) surface has been studied by high-resolution electron-energy-loss spectroscopy, photoemission and Auger spectroscopy, and low-energy electron diffraction from 100 to 1150 K. C60 forms strong covalent bonds with Pt with very small charge transfer (<0.8 electrons/molecule from C60 to the substrate), has a low surface mobility, and decomposes at about 1050 K, leaving a multidomain graphitic surface layer. C60 decomposes also on Ni(110) at about 760 K, forming a carbidic carbon layer, which transforms into graphitic carbon at higher temperatures. Both surfaces act as a catalyst for the fragmentation proces
Temperature and momentum dependence of the spectral function of the charge-density wave and of the normal α phase of Pb/Ge(111)
No full textAngle-resolved high-resolution photoemission spectra of the α phase of Pb/Ge(111)-(√3×√3)R30° have been measured below (100 K) and above (300 and 500 K) the transition to a charge-density-wave insulator state. The spectra strongly differ from those expected from the published local density approximation calculations showing a surface band without dispersion and correlation and fluctuation effects also at high temperature. A pseudogap is observed at 100 K
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
- …
