5 resultados para 689
Resumo:
The optimization of solution-processed organic bulk-heterojunction solar cells with the acceptor-substituted quinquethiophene DCV5T-Bu-4 as donor in conjunction with PC61BM as acceptor is described. Power conversion efficiencies up to 3.0% and external quantum efficiencies up to 40% were obtained through the use of 1-chloronaphthalene as solvent additive in the fabrication of the photovoltaic devices. Furthermore, atomic force microscopy investigations of the photoactive layer gave insight into the distribution of donor and acceptor within the blend. The unique combination of solubility and thermal stability of DCV5T-Bu-4 also allows for fabrication of organic solar cells by vacuum deposition. Thus, we were able to perform a rare comparison of the device characteristics of the solution-processed DCV5T-Bu-4:PC61BM solar cell with its vacuum-processed DCV5T-Bu-4:C-60 counterpart. Interestingly in this case, the efficiencies of the small-molecule organic solar cells prepared by using solution techniques are approaching those fabricated by using vacuum technology. This result is significant as vacuum-processed devices typically display much better performances in photovoltaic cells. Keywords
Resumo:
[EN] One universal feature of human languages is the division between grammatical functors and content words. From a learnability point of view, functors might provide entry points or anchors into the syntactic structure of utterances due to their high frequency. Despite its potentially universal scope, this hypothesis has not yet been tested on typologically different languages and on populations of different ages. Here we report a corpus study and an artificial grammar learning experiment testing the anchoring hypothesis in Basque, Japanese, French, and Italian adults. We show that adults are sensitive to the distribution of functors in their native language and use them when learning new linguistic material. However, compared to infants’ performance on a similar task, adults exhibit a slightly different behavior, matching the frequency distributions of their native language more closely than infants do. This finding bears on the issue of the continuity of language learning mechanism.
Resumo:
689 p.
Resumo:
En el contexto social actual, la profesión del conservador-restaurador de obras de arte cuenta con un reconocimiento bien definido conseguido tras la sedimentación progresiva de unos conocimientos científico-técnicos que cuentan con entidad propia. La profesión, como tal, se encuentra sustentada en unos pilares de conocimiento científico-técnico y humanístico que le facilitan el poder cumplir con la alta responsabilidad que conlleva la salvaguarda del patrimonio artístico. Recaen en este perfil profesional las normas internacionales que la regulan y la evolución científica del conocimiento que se alcanza en el siglo XX respaldando a la especialidad. Por otra parte, las demandas sociales del poder de las imágenes y su asombro ante los objetos singulares establecen unas necesidades que también recaen en este perfil profesional.
Resumo:
Homenaje a Ignacio Barandiarán Maestu / coord. por Javier Fernández Eraso, Juan Santos Yanguas.