Light emitting devices based on nanostructured semiconductors

Light emitting devices based on high-efficiency photoluminescence (PL) fluorescent nanocrystals have been investigated in terms of the generation of light from the structure using a variety of deposition methods. An automated modified layer-by-layer (LbL) self-assembly technique has been employed to produce multilayers of thiol-capped red fluorescing CdTe nanocrystals. Indium- tin-oxide (ITO) and aluminium electrodes were used as the electrodes. Morphological characterization was carried out through Schottky field effect (SFEG) SEM and atomic force microscopy (AFM). The structures built presented clear red electroluminescence (EL) to the naked eye. Turn on voltages were found to be in the range of 3-6 volts while the onset current was in the order of tens of microamperes. The role of structure homogeneity, the presence of pinholes and lifetime extension were features addressed during this investigation. Samples with a lifetime of continuous operation in air longer than 60 minutes and highly stable EL spectra were achieved; EL was visible to the unaided eye, although the brightness was still below the commercial standards and has not yet been qualified

Beyond church and court: city musicians and music in Renaissance Valladolid

Texte disponible mis en page sur le site de l'éditeur : http://em.oxfordjournals.org/content/37/3.tocInternational audienceThe study of urban music has often been focused on court or church studies and, as a result, the analysis of music and music-making has been largely limited to these two particular environments. The 'new' vision proposed in the research presented here seeks, however, to examine the place that music occupied in the whole social system, following natural laws of association and dissociation. The role played by music in this new broader context can thus be integrated into what French historiographers have called the 'history of representations', a vision associated with private or public performances and their aesthetics. As musicologists, we are seeking to broaden our knowledge in this area by contributing to present-day interest in the musicians and music-makers in the everyday life of a Spanish town, telling the story of 'those without history'. The present article seeks to offer a documentary view of civilian life in 16th-century Valladolid: this will lead us to examine how music melted into the urban tissue in order to understand more about the way music was performed, taught, sold and transmitted

Morales in Plasencia and " New " Works form his Early Compositional Period

International audienceWhile some recent publications have shed new light on his works, nothing new has been recently been published on Cristobal de Morales's life following the hypothesis published in 2002 by Alison Sanders MacFarland (pointing out a Toledan connexion for the composer), a hypothesis later questioned by Robert Stevenson, one of his main biographers. This article thus seeks to open a new chapter on this composer's life and career prior to his Roman period, or more precisely speaking, during his time as "maestro de capilla" of Plasencia cathedral where the first traces of his activity can be found in its archives

El léxico musical del Renacimiento: premisas para un estudio

International audienc

Unedited Motets by a Little Known Composer: Alonso Ordóñez

International audienceMany Iberian composers of the Renaissance remain to be rediscovered and studied: bringing them out of the obscurity of anonymity has been a task for scholar and performers, often motivated by an almost quixotic spirit, over many years. At the forefront of this quixotic endeavour has been Bruno Turner whose pioneering work as editor and conductor has long been dedicated to bringing to light little known composers of the Spanish Renaissance. My own contribution to this volume follows in Bruno's footsteps and directs the spotlight on one of the many composers who marked Spain out musically in the sixteenth century: Alonso Ordóñez. 1 A A O The only details of Ordóñez's life currently in the scholarly domain are summarized in José López-Calo's entry for the Diccionario de la Música Española e Hispanoamericana, 2 and these will shortly be expanded by Juan The choice of this composer is deliberate. I first met Bruno Turner at the Medieval and Renaissance Music Conference in Bangor in. At the time he was intrigued as to the identity of the composer of an anonymous Mass based on a motet by Morales preserved in a Mexican source at the Newberry Library. When he showed me the score, a mixture of enthusiasm and inexperience immediately led me to suggest Alonso Or-dóñez. Of course, such an attribution is impossible to verify, but it meant that I acquired first-hand experience of Bruno's affability and patience with young musicologists like myself. His friendship and encouragement since our first meeting hava meant a great deal to me. José López-Calo, 'Ordóñez', DMEH, : a

Second record of Tadarida brasiliensis (I. Geoffroy St.-Hilaire, 1824) (Chiroptera, Molossidae) in Santa Cruz Province, Argentina

Although Tadarida brasiliensis is one of the most widely distributed species of bats in Argentina, it is nevertheless extremely scarce in Patagonia. We report a second record of T. brasiliensis for Santa Cruz province, which fills a gap in the geographical distribution of this species in that province and is also the third southernmost record for the species and for any molossid bat in the world.Fil: Zapata, Sonia Cristina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Procopio, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Morgenthaler, Annick. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Travaini, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentin

Bilirubin oxidase from myrothecium verrucaria physically absorbed on graphite electrodes. Insights into the alternative resting from and the sources of activity loss

The oxygen reduction reaction is one of the most important chemical processes in energy converting systems and living organisms. Mediator-less, direct electro-catalytic reduction of oxygen to water was achieved on spectrographite electrodes modified by physical adsorption of bilirubin oxidases from Myrothecium verrucaria. The existence of an alternative resting form of the enzyme is validated. The effect on the catalytic cycle of temperature, pH and the presence of halogens in the buffer was investigated. Previous results on the electrochemistry of bilirubin oxidase and on the impact of the presence of halogens are reviewed and reinterpreted