86,814 research outputs found
Leaky atomic traps: upward diffusion of Au from nanopits on ionic crystal surfaces
No full textWe have investigated the formation of gold nanoclusters during submonolayer deposition on atomically flat KBr and RbI (001) ionic-crystal substrates, as well as on substrates patterned with two-dimensional (2D) nanoscale pits produced by electron stimulated desorption. In this way, it is possible to produce atomic steps free from stress and local charging, which are normally considered the reason for enhanced cluster nucleation. Easy nucleation of the Au clusters inside the pits at the lower side of the atomic step edge is not observed, while nucleation of the Au nanoclusters is found to occur preferentially at the upper step edges. Moreover, we observe that gold atoms landing inside the bottom of the pits are able to escape from them by means of thermally activated upward diffusion at the step edges. We propose that the preferential Au nucleation sites at the edges of 2D pits are activated by F centers produced in electronic processes used for nanopatterning of the ionic crystals
Variations on the Author
No full text“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
Metal nanostructures assembled at semiconductor surfaces studied with high resolution scanning probes
No full text
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation
No full textThe desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters
Scanning probe microscopy study of height-selected Ag/Ge(111) nanomesas driven by quantum size effects
No full textWe present scanning tunnel microscope, noncontact atomic force microscopy, Kelvin probe force microscopy, and low-energy electron diffraction study of the morphological evolution of Ag ultrathin films (0.5-6 ML) grown at 150 K on Ge(111)-c(2×8) substrate. Although the system has been widely studied in the context of quantum confinement effects in the electronic structure of these films, no real-space imaging has been reported so far. Our results demonstrate that upon annealing to room temperature, the Ag film adopts a (111) epitaxy on top of a wetting layer. It has been found that the Ag film adopts a metastable morphology which is determined by a delicate interplay between thermodynamics and the kinetics of interlayer mass transport. The preferential population of a discrete set of the deposit heights at 6, 10, and 12 ML suggests that quantum size effects are indeed active for the Ag/Ge system. Kelvin probe force microscopy indicates that the surface potential depends monotonically on the film thickness and does not show any oscillatory behavior in correspondence to the height change
- …
