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Is well known that if you add volcanic ashes to limestone mortars it actually adds up hydraulic properties. In fact, mortars and hydraulic concrete with additives and ashes are known since roman century. Actual studies of the behavior of mortars that were utilized in the past in some ancient buildings doesn't have a clue of were theses arid comes from, that is something that is not going to be happening in this work because all the arid we have is already known were it is from and all the aspects we need to know in order to work with it. Eternity is a word that is not appropriate to use it in a building, but being able to make them last thru eternity is out job, that is why in this project we are trying to make mortars which could be used in this type of jobs. Utilizing the aerial lime which is the raw material we know is most present in those type of projects. The eruption is produced by the expansion of the fluids contained in magma, in the final conduit of the volcano. For the development of the thesis, we have selected two main situations which are Tenerife (TE) and GC (Gran Canarias), from the Mediterranean. This aggregates were taken from the different eruption in volcanos located near this areas. In certain volcanic zones (Mediterranean Zone, Cerdeña, NE peninsular. Canarias, middle and south America, Guatemala, El Salvador, Colombia, Ecuador, Peru, Chile) they are natural deposits of volcanic ashes "lapilli" (pyroclastic fragments, expulsed by a Vulcan during an eruption and with a variable diameter in between 2 – 64 mm). Chemical Composition, speed of pozzolanic reaction, the color, they are different. Economic factor is going to be very present in the characteristics of the mortars. All the mortars worked in the project are easily found in their natural ambient like we are going to be using them. There is no need of smashing them or make them pass thru a process which involves money. Another fact that we have to bring is the liquid fragmentation of innumerable drops of ashes in reduced dimensions, also a very important surface growth (after glass) generating gas in this liquid, this air bubbles produced in this paste which make the dry process easier to accomplish. This fact also enables rapid cooling. Making a violently access to the atmosphere and preventing it from their widespread crystallization, all this resulting in the formation of pyroclastic, very glassy vesicular fragments or cell magma. Currently, this fact artificially propagated during thermal expansion of perlite hydrated natural glass type. It is proposed to optimize dosages of air lime mortars with different types of volcanic aggregates, both physically and mechanically, and determine its artificial accelerated aging to aggressive agents (soluble salts, freeze-thaw). Special attention will be done on the study of pozzolanic behavior, both in terms of known compounds are formed, and in terms of determining the reaction rate. This process which involves the formation of the rock is the responsible for the higher porosity found in these type of stones.

La realització d'estudis de LCA per a sistemes fotovoltaics és una eina essencial per mesurar el seu nivell de sostenibilitat En aquest sentit, i després de la realització d' una anàlisi teòrica dels estudis publicats de LCA dels sistemes fotovoltaics, s'han trobat algunes llacunes. Aquestes llacunes es refereixen a la manca de varietat d'indicadors de LCA, on la majoria dels estudis depenen del temps de retorn energètic, sent aquest gairebé l'únic indicador (no es té en compte l'ús dels mètodes de perfil ambiental). A més, s'observen dues bretxes relatives a la manca d'estudis de LCA destacant la integració en edificis d'energia solar d'una banda, i l'ús de la tecnologia fotovoltaica de concentració per un altre. Per tant, en aquesta tesi, es presenta una nova aportació al camp dels estudis LCA dels sistemes fotovoltaics integrats en edificis. Això s'aconsegueix a través de l'avaluació ambiental i energètica dels sistemes de concentració fotovoltaica integrats en edificis (BICPV). Els resultats es presenten en termes de metodologies d'avaluació de l' impacte del cicle de vida (perfil mediambiental), així com el temps d'amortització de l'Energia i el Factor de Retorn (perfil energètic). Els resultats, amb el suport de les anàlisis de sensibilitat i la comparació amb un sistema convencional fotovoltaic per a integració en edificis (BIPV), mostren beneficis ambientals significatius que poden ser obtinguts a través de sistemes BICPV. A Finalment, es discuteixen les recomanacions per a treballs i millores futures.

A hybrid photovoltaic/thermal transient model has been developed and validated experimentally. The methodology extends the quasi-dynamic thermal model stated in the EN 12975 to involve the electrical performance and to consider the dynamic behaviour minimising constraints when characterising the collector. A backward moving average filtering procedure has been applied to improve the model response for variable working conditions. Concerning the electrical part, the model includes the thermal and radiation dependences in its variables. The results revealed that the characteristic parameters included in the model reasonably agree with the experimental values obtained from standard steady-state and IV characteristic curve measurements. After a calibration process the proposed model is a suitable tool to predict the thermal and electrical performance of a hybrid solar collector, for a specific weather data set.