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Línea aérea de 132 kV para el transporte de 100 MVA

  • Díaz González, Eva
El objetivo del presente proyecto es describir, calcular y diseñar los elementos que forman parte de las instalaciones de una línea de evacuación de 100 MVA de energía eléctrica a 132 kV de tensión. Para ello se fijarán las características técnicas que deben cumplir las partes del sistema para un perfecto y eficaz funcionamiento, cumpliendo además con las prescripciones impuestas por las reglamentaciones y disposiciones oficiales vigentes., Ingeniería Técnica en Electricidad
Proyecto:


Self-organized nanopattrening of silicon surfaces by ion beam sputtering

  • Muñoz-García, Javier
  • Vázquez Roy, José Luis
  • Cañadas Castro, Mario
  • Gago, Raúl
  • Redondo-Cubero, Andrés
  • Moreno-Barrado, Ana
  • Cuerno, Rodolfo
In recent years Ion Beam Sputtering (IBS) has revealed itself as a powerful technique to induce surface nanopatterns with a large number of potential applications. These structures are produced in rather short processing times and over relatively large areas, for a wide range of materials, such as metals, insulators, and semiconductors. In particular, silicon has become a paradigmatic system due to its technological relevance, as well as to its mono-elemental nature, wide availability, and production with extreme flatness. Thus, this review focuses on the IBS nanopatterning of silicon surfaces from the experimental and the theoretical points of view. First, the main experimental results and applications are described under the light of the recently established evidence on the key role played by simultaneous impurity incorporation during irradiation, which has opened a new scenario for an improved understanding of the phenomenon. Second, the progress and state-of-art of the theoretical descriptions of the IBS nanopatterning process for this type of targets are discussed. We summarize the historical approach to IBS through simulation techniques, with an emphasis on recent information from Molecular Dynamics methods, and provide a brief overview of the earlier and most recent continuum models for pure and compound systems., This work has been partially supported by the Spanish Ministries of Science and Innovation (grants Nos. FIS2009-12964-C05-01, FIS2009-12964-C05-03, FIS2009-12964-C05-04, and BES-2010-036179) and of Economy and Competitiveness (grants Nos. FIS2012-38866-C05-01 and FIS2012-38866-C05-05, FIS2012-32349 and FIS2013-47949-C2-2). A.R.C. also acknowledges funding from SFRH/BPD/74095/2010 (Portugal) and from Juan de la Cierva program (Spain) under contract No. JCI-2012-14509., Publicado
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Nonuniversality due to inhomogeneous stress in semiconductor surface nanopatterning by low-energy ion-beam irradiation

  • Moreno-Barrado, Ana
  • Cañadas Castro, Mario
  • Gago, Raúl
  • Vázquez Roy, José Luis
  • Muñoz-García, Javier
  • Redondo-Cubero, Andrés
  • Galiana Blanco, Beatriz
  • Ballesteros Pérez, Carmen Inés
  • Cuerno, Rodolfo
A lack of universality with respect to ion species has been recently established in nanostructuring of semiconductor surfaces by low-energy ion-beam bombardment. This variability affects basic properties of the pattern formation process, like the critical incidence angle for pattern formation, and has remained unaccounted for. Here, we show that nonuniform generation of stress across the damaged amorphous layer induced by the irradiation is a key factor behind the range of experimental observations, as the form of the stress field is controlled by the ion/target combination. This effect acts in synergy with the nontrivial evolution of the amorphous-crystalline interface. We reach these conclusions by contrasting a multiscale theoretical approach, which combines molecular dynamics and a continuum viscous flow model, with experiments using Xe+ and Ar+ ions on a Si(100) target. Our general approach can apply to a variety of semiconductor systems and conditions., This work has been partially supported by MICINN (Spain) Grant MAT2011-13333-E, and MINECO (Spain) Grants FIS2012-38866-C05-01, FIS2012-38866-C05-05, FIS2013-47949-C2-2-P and FIS2012-32349. TEM work has been conducted at LABMET laboratory, associated with Red de Laboratorios of CAM, Spain. A.M.-B. acknowledges support from MINECO, through FPI scolarship BES-2010-036179. A.R.C. acknowledges funding from Juan de la Cierva program (Spain) under Contract No. JCI-2012-14509., Publicado
Proyecto:


Ion damage overrides structural disorder in silicon surface nanopatterning by low-energy ion beam sputtering

  • Moreno-Barrado, Ana
  • Gago, Raúl
  • Redondo-Cubero, Andrés
  • Vázquez Roy, José Luis
  • Muñoz-García, Javier
  • Cuerno, Rodolfo
  • Lorenz, Katharina
  • Cañadas Castro, Mario
We investigate the role of the initial structural condition in silicon surface nanopatterning by low-energy ion beam sputtering. Specifically, we address the influence of the target atomic structure in ripple formation under oblique irradiation by 500 eV Ar+ ions. To this end, we compare results obtained on single-crystal, amorphous, and pre-implanted silicon targets. In spite of the differences in terms of structural order, and in contrast to previous results for medium energies, surface dynamics are found to be quantitatively similar in all these systems. We explain our results through molecular dynamics simulations of the initial irradiation stages, with the conclusion that the damage induced by low-energy ion bombardment overrides the initial atomic state of the silicon target, irrespectively of its preparation method and allows silicon re-using for nanostructuring., This work has been partially supported by MICINN (Spain) grant MAT2011-13333-E, MINECO (Spain) grants FIS2012-38866-C05-01, FIS2012-38866-C05-05, FIS2012-32349, FIS2013-47949-C2-2-P, and Comunidad Autónoma de Madrid grant NANOAVANSENS S2013/MIT-3029. AM-B and AR-C acknowledge support from MINECO (SPAIN) through FPI scolarship BES-2010-036179 and Juan de la Cierva contract No. JCI-2012-14509, respectively., Publicado
Proyecto:


Stress vs sputtering effects in the propagation of surface ripples produced by ion-beam sputtering

  • Moreno-Barrado, Ana
  • Cañadas Castro, Mario
  • Muñoz-García, Javier
  • Cuerno, Rodolfo
The proceeding at: 19th International Conference on Ion Beam Modification of Materials (IBMM 2014). Took place at 2014, September, 14-19, in Bruges (Belgium). The event Web Site in https://iks32.fys.kuleuven.be/indico/event/16/, Under low energy ion irradiation, periodic features (ripples) can develop on the surfaces of semiconductor materials, with typical sizes in the nanometric range. Recently, a theory of pattern formation has been able to account for the variability with the ion/target combination of the critical angle value separating conditions on ion incidence that induce the presence or the absence of ripples. Such a theory is based in the accumulation of stress in the damaged irradiated layer and its relaxation via surface-confined viscous flow. Here we explore the role of stress, and its competition with purely erosive mechanisms, to deter-mine the sign of the velocity with which the ripple pattern moves across the target plane. Based on this theory, we discuss different situations and make specific testable predictions for the change of sign in that velocity., Our work has been funded through MINECO (Spain) grants FIS2012-38866-C05-01, FIS2012-32349, and FIS2013-47949-C2-2. A.M.-B. acknowledges support from MINECO, through FPI scholarship BES-2010-036179., Publicado
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Historia pandectarum seu factum exemplaris florentini : accedit gemina dissertatio de Amalphi ..

  • Brencmanni, Henrici
Port. a dos tintas, Sign.:*-2*\p4\s, A-Z\p4\s, 2A-2Z\4\s,3A-3M\p4\s, 3N\p2\s, *\p4\s, 2*\p2\s, [A-K]\p4\s, L\p2\s
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A comparison of the Web of Science with publication-level classification systems of Science

  • Perianes Rodríguez, Antonio
  • Ruiz-Castillo, Javier
In this paper we propose a new criterion for choosing between a pair of classification systems of science that assign publications (or journals) to a set of clusters. Consider the standard target (citedside) normalization procedure in which cluster mean citations are used as normalization factors. We recommend system A over system B whenever the standard normalization procedure based on system A performs better than the standard normalization procedure based on system B. Performance is assessed in terms of two double tests &-one graphical, and one numerical&- that use both classification systems for evaluation purposes. In addition, a pair of classification systems is compared using a third, independent classification system for evaluation purposes. We illustrate this strategy by comparing a Web of Science journal-level classification system, consisting of 236 journal subject categories, with two publication-level algorithmically constructed classification systems consisting of 1,363 and 5,119 clusters. There are two main findings. Firstly, the second publication-level system is found to dominate the first. Secondly, the publication-level system at the highest granularity level and the Web of Science journal-level system are found to be non-comparable. Nevertheless, we find reasons to recommend the publication-level option., This research project builds on earlier work started by Antonio Perianes- Rodriguez during a research visit to the Centre for Science and Technology Studies (CWTS) of Leiden University as awardee of José Castillejo grant, CAS15/00178, funded by the Spanish MEC. Ruiz- Castillo is a visiting researcher at CWTS and gratefully acknowledges CWTS for the use of its data. Ruiz-Castillo acknowledges financial support from the Spanish MEC through grant ECO2014-55953- P, as well as grant MDM 2014-0431 to his Departamento de Economía.
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Línea aérea de 132 kV para el transporte de 75 MVA

  • Campillo Gómez, Rafael
En el presente proyecto, se han descrito, calculado y diseñado los elementos que forman parte de una línea aérea de alta tensión (132 kV) para el transporte de energía eléctrica (75 MVA). Para ello se ha seguido lo indicado en el Reglamento Técnico de Líneas Eléctricas de Alta Tensión de 2008 y sus Instrucciones Técnicas Complementarias. Todo lo relativo al proyecto se especifica en los seis documentos de los que el mismo consta: memoria, cálculos justificativos, pliego de condiciones, presupuesto, planos y bibliografía., Ingeniería Técnica en Electricidad
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Propuestas de cambios en el mercado eléctrico español para aumentar el volumen y la competitividad en los mercados a plazo

  • Hernández Alonso, Noé
La energía se ha convertido en la actualidad en un pilar básico que influye en todos los ámbitos de las sociedades avanzadas, desde las grandes industrias hasta las casas pasando por los servicios como hospitales o transporte. Por ello el sector energético se ha convertido en un sector clave para todos los países. Una pieza importante dentro del sector energético español es el mercado eléctrico, en el cual los agentes de mercado (generadores y consumidores) transaccionan la energía que unos generan y los otros consumen. El buen funcionamiento del mercado eléctrico repercute directamente sobre muchos otros sectores del país los cuales son consumidores de energía eléctrica. Por ejemplo la competitividad de la industria electrointensiva, consumidora de grandes volúmenes de energía eléctrica, depende en gran medida de su precio final, principalmente del precio en el mercado eléctrico. Lo mismo le ocurre al consumidor pequeño, como los domésticos. Por todo esto el presente proyecto fin de carrera nace con la finalidad de analizar el comportamiento actual del mercado eléctrico español en busca de deficiencias o posibilidades de mejora, para posteriormente realizar propuestas que pudieran mejorar su funcionamiento., Ingeniería Técnica en Electricidad
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