Development of functionalized aerogels for applications as catalyst and hydrides matrix

Los hidruros son una alternativa en el almacenamiento de H2. Estos elementos al ser calentados liberan el combustible. En esta tesis se ha propuesto el confinamiento de hidruros en materiales mesoporosos con el fin de mejoras sus cinéticas de descomposición. Para ello se han desarrollado aerogeles haciendo uso de la tecnología supercrítica. Además se ha modificado la naturaleza química de la superficie de estos soportes, controlando así las interacciones entre el soporte y el material confinado en ellos. Por otro lado, creando aerogeles cuya estructura contiene carbono, se han modificado las propiedades dieléctricas de los mismos. Ésto, ha permitido el uso de microondas para su calentamiento, de una forma más rápida y homogénea, consiguiendo así una liberación de H2 más eficiente y controlada. Por último se ha desarrollado un plan de empresa (LightEnergy) que propone la aplicación de la tecnología desarrollada al mundo de las celdas de combustible.Departamento de Ingeniería Química y Tecnología del Medio AmbienteDoctorado en Ingeniería Química y Ambienta

Weathering Processes on Sandstone Painting and Carving Surfaces at Prehistoric Rock Sites in Southern Spain

The sandstones which constitute the host rock for the prehistoric artwork in the Rock Groups of Tajo de las Figuras and Peñas de Cabrera (southern Spain) show a serious degree of alteration, due both to natural processes and those related to anthropogenic and animal activity. A detailed study was carried out on the petrological and compositional characteristics of the sandstones (fresh and altered rock) in both rock groups, and on the geological and climatological characteristics of the area in which they are located. The sandstones have very similar petrological and compositional characteristics in both areas. This likeness causes the nature of the natural weathering processes to be similar in the rock areas studied. These processes can be divided in terms of the predominant mechanisms of alteration into three inter-related categories: mechanical weathering, chemical weathering, and bio-induced alteration processes. However, the different climatic conditions of the areas in which the two rock areas are located directly influences the intensity of these processes. The precipitation and the range of temperature variation with heavy winter frosts in the area of El Tajo de las Figuras are significantly higher than in the area of Peñas de Cabrera; this translates into a higher rate of weathering at El Tajo de las Figuras. Regarding the anthropogenic action, two types of influence on the deterioration can be distinguished: a direct one, which consists of scouring and wetting of the walls in order to increase the chromatic contrast; and an indirect one, which is the extraction of blocks of sandstone in the upper part of rock shelters, which in turn encourages the development of the chemical weathering processes.This study forms part of the research agreement “Study and diagnosis of the archaeological groups and deposits of the Autonomous Community of Andalusia in their geomorphological, biological and climatic contexts” financed by the Culture Council, Junta of Andalusia (Spain)

Four layouts of the Cathedral of Valladolid in one drawing. The new copy of Rivera Manescau's plan

[ES] La Catedral de Valladolid representa, pese a lo inacabado de sus fábricas, uno de los hitos del clasicismo en la arquitectura española del renacimiento. Su solar ha sido cuna del desarrollo medieval de la ciudad sobre el que, por su relevante posición topográfica, se han sucedido hasta cuatro templos. En 1943 apareció en la prensa local un plano que representaba esa superposición de colegiatas iniciada en el siglo XI. Ese plano se perdió y en la actualidad los autores han logrado localizar una nueva copia. Es objeto de este trabajo la publicación de esa nueva copia y su análisis gráfico, comprobando con la realidad su veracidad histórica, para concluir con una serie de reconstituciones digitales de los cuatro templos que aparecen en él representados.[EN] The Cathedral of Valladolid represents, despite the unfinished nature of its stone walls, one of the landmarks of classicism in Spanish Renaissance architecture. Its site has been the cradle of the medieval development of the city on which, due to its relevant topographical position, up to four temples have been built. In 1943 a plan appeared in the local press that represented this overlapping of collegiate churches that began in the 11th century. That plan was lost and today the authors have managed to locate a new copy. The object of this work is the publication of this new copy and its graphic analysis, comparing its historical veracity with reality, to conclude with a series of digital reconstructions of the four temples that appear in it.Gimeno Sanz, C.; Moral García, Á.; Carazo Lefort, E. (2023). Cuatro trazados de la Catedral de Valladolid en un dibujo. La nueva copia del plano de Rivera Manescau. EGA Expresión Gráfica Arquitectónica. 28(48):156-167. https://doi.org/10.4995/ega.2023.19882156167284

Percepción de la Calidad de Vida en personal de enfermería de Servicio de Urgencias de Valladolid

La percepción de la Calidad de Vida en el personal sanitario del Servicio de Urgencias en un hospital, cuya carga de trabajo es bastante intensa, es escasa pero a la vez gratificante pues la ayuda prestada en cuidados es amplia y satisfactoria. Para valorar la calidad de vida del equipo de enfermería del Servicio de Urgencias del Hospital Clínico Universitario de Valladolid se realiza un estudio tomando una muestra de 39 personas que trabajan en activo en dicha Unidad. Se valorarán 35 ítems teniendo en cuenta determinadas variables como son el sexo, la edad, la antigüedad, la jornada que realizan y el tipo de plaza que ocupan.Departamento de enfermeríaGrado en Enfermerí

Grado de conocimiento de los pacientes diabéticos tipo II sobre las complicaciones oculares derivadas de su patología

La percepción del nivel de conocimientos en la población de diabéticos tipo II sobre su patología es escasa, siendo mejorable si prestamos ayuda amplia y personalizada. Para valorar la calidad de conocimientos que poseen estos diabéticos sobre su enfermedad y las posibles complicaciones oculares derivadas de su patología, se realizó un estudio tomando una muestra de 77 personas diabéticas tipo II que acuden a consulta de Atención Primaria al Centro de Salud “Tórtola” de Valladolid. Se valoraron 25 ítems teniendo en cuenta determinadas variables como son el sexo, la edad, el estado civil, la ocupación, el nivel educativo, el tiempo de evolución de la enfermedad y el tratamiento.Máster en Enfermería Oftalmológic

Caso práctico de interpretación de imágenes WINr de radar en modo Doppler

Ponencia presentada en: XXIX Jornadas Científicas de la AME y el VII Encuentro Hispano Luso de Meteorología celebrado en Pamplona, del 24 al 26 de abril de 2006

Tormenta severa en Santander: 24 de junio de 2003

Ponencia presentada en: XXIX Jornadas Científicas de la AME y el VII Encuentro Hispano Luso de Meteorología celebrado en Pamplona, del 24 al 26 de abril de 2006

Analysis, design, and implementation of the AFZ converter applied to photovoltaic systems

Grid-tied photovoltaic (PV) installations with Distributed Maximum Power Point Tracking (DMPPT) architectures include a DC-DC Module Integrated Converter (MIC) for managing each PV panel, isolating it from the others, reducing the mismatching effect and maximizing the harvested power. In this paper, the Autotransformer Forward converter with type-Zeta resonant reset (AFZ) is proposed as a DMPPT architecture MIC candidate. The main characteristics of the AFZ converter are the high versatility due to its voltage step-up and step-down capability; the use of an optimized autotransformer with only two windings, reducing the complexity and power losses of this component; the good dynamic performances, like the Forward converter ones; the low number of components and the simplicity and high feasibility associated to the use of just one active switch. Besides, soft switching transitions are achieved thanks to the autotransformer type-Zeta resonant reset. The steady-state theoretical analysis, considering the effect of the autotransformer leakage inductance, is presented. The converter is also studied in the frequency domain, obtaining the small-signal transfer functions. A design procedure based on the requirements of a 100 kW grid-tied photovoltaic installation is described, yielding in a 225 W prototype with efficiencies up to 95.6 %. Experimental results validate the theoretical analysis.Comment: This work was supported in part by the Spanish Ministry of Economy and Competitiveness and FEDER funds through the research project: Modeling and Control Strategies for the Stabilization of the Interconnection of Power Electronic Converters CONEXPOT under Grant DPI2017-84572-C2-2-R. copyright: 2020 IEE

Analysis and implementation of the Buck-Boost Modified Series Forward converter applied to photovoltaic systems

The mismatching phenomenon is one of the main issues in photovoltaic (PV) applications. It could reduce the generated power of a string when a PV panel has different performances from the other PV panels connected to the same string. Distributed Maximum Power Point Tracking (DMPPT) architectures are one of the most promising solutions to overcome the drawbacks associated with mismatching phenomena in PV applications. In this kind of architectures, a DC-DC module integrated converter (MIC) manages each PV panel, isolating it from the rest of the PV panels, for harvesting the maximum available power from the Sun. Due to the high number of DCDC converters used in a grid-tied PV installation, the most desired MIC requirements are high efficiency, low cost and the capability of voltage step-up and step-down. This paper proposes the Buck-Boost Modified Forward (BBMSF) converter as a good candidate to be applied in DMPPT architectures. A complete analysis of the BBMSF converter is carried out, including the steady-state analysis as well as the small signal analysis in continuous conduction mode. The main advantages of the BBMSF converter are its step-up and step-down voltage transfer function; a higher simplicity, since it only includes a single controlled switch; the soft switching characteristics in all the diodes and MOSFET, reaching in some cases ZVS and ZCS, and yielding high efficiencies; the use of an autotransformer, with better performances than a typical Forward transformer; and the good dynamic performance, like the Forward converter ones. The theoretical analyses are validated through the experimental results in a 225 W BBMSF prototype designed and built under the requirements of a 100 kW grid-tied PV installation, achieving an efficiency up to 93.6%.Comment: This work has been supported by the Ministry of Economy and Competitiveness and FEDER funds through the research project "Storage and Energy Management for Hybrid Electric Vehicles based on Fuel Cell, Battery and Supercapacitors" - ELECTRICAR-AG- (DPI2014-53685-C2-1-R