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The presence of heavy metals in craft beers can endanger human health if the total metal content exceeds the exposure limits recommended by sanitary standards; in addition, they can cause damage to the quality of the beer. In this work, the concentration of Cd(II), Cu(II), and Fe(III) was determined in 13 brands of craft beer with the highest consumption in Quito, Ecuador, by differential pulse anodic stripping voltammetry (DPASV), using as boron-doped diamond (BDD) working electrode. The BDD electrode used has favorable morphological and electrochemical properties for the detection of metals such as Cd(II), Cu(II), and Fe(III). A granular morphology with microcrystals with an average size between 300 and 2000 nm could be verified for the BDD electrode using a scanning electron microscope. Double layer capacitance of the BDD electrode was 0.01412 μF cm−2, a relatively low value; Ipox/Ipred ratios were 0.99 for the potassium ferro-ferricyanide system in BDD, demonstrating that the redox process is quasi-reversible. The figures of merit for Cd(II), Cu(II), and Fe(III) were; DL of 6.31, 1.76, and 1.72 μg L−1; QL of 21.04, 5.87, and 5.72 μg L−1, repeatability of 1.06, 2.43, and 1.34%, reproducibility of 1.61, 2.94, and 1.83% and percentage of recovery of 98.18, 91.68, and 91.68%, respectively. It is concluded that the DPASV method on BDD has acceptable precision and accuracy for the quantification of Cd(II), Cu(II), and Fe(III), and it was verified that some beers did not comply with the permissible limits of food standards.

The world is going through a constant evolution, where the objectives are much more ambitious than before thanks to the new technologies. However, the focus is no longer on only improving existing services without considering anything else; nowadays, the benefit provided is just as important as the way in which it is achieved, and the main efforts currently are focused on achieving a sustainable world, in which life continues to be as we know it and climatic catastrophes are eradicated, at least those in which human activity is the main cause. That is why this thesis is focused on the implementation in the aeronautical industry of a promising technology called Active Flow Control (AFC). To that end, an exhaustive state-of-the-art is conducted in which the AFC technology is described in general, to then deep dive in its aeronautical applications. Next, the technology required so as to implement the AFC in an aircraft is described, covering the main elements needed to influence the flow around the aircraft together with the power supply architectures necessary to feed the actuators. On the other hand, and based on the information previously gathered, a Minimum Viable Product (MVP) is defined, in which AFC technology is to be implemented in an Airbus A-320 aircraft. In the MVP, both the technological elements that need to be installed together with the system infrastructure are established, thus defining the architecture of the product. In order to ensure the viability and profitability of the MVP, a feasibility study is conducted, analysing the installation of the product from an airline perspective considering three different casuistic: an aircraft that flies only at national level in Spain, an aircraft that flies at international level in Europe and a complete fleet of Airbus A-320 that flies at international level in Europe. The preliminary economic analysis covers the three cases mentioned, and the complete economic figures are presented for the third case, the one with more practical interest. On the other hand, the regulatory emissions framework currently in place in Europe is described, assessing whether the installation of the MVP in a European airline could influence the overall company strategy towards the 2050 zero net goal achievement. Due to the current situation, in which the global awareness of contaminant gases emissions has increased considerably, all the projects aiming to reduce this type of emissions have a great impact in the industry, and the AFC technology investigations are a good opportunity to improve aeronautical industry contaminant footprint in the world.

[EN] The experience described is situated in the Juan Canalejo Aff ordable Housing Colony in A Coruña, one of the many colonies of this kind that appeared in the post-war period (1948) on the basis of the Aff ordable Housing Law of 1911 and shortly before the fi rst Land Law in Spanish territory. The interest of the project lies in the resolution of an untried Ordinance, justifying an action that does not alter the environmental conditions of a subzone in relation to the appearance of extemporaneous pieces, to the legality and expectations of the Town Planning that defi nes them. The most recognisable elements of the type are maintained: arched access that generates a hallway (even inserting a staircase that did not previously exist), composition of openings and rhythm of the existing fl oor plan and conservation of the original shape of the roof, a cornice that remains in its original place - instead of being moved to the upper fl oor - and which acts as a support for the passive behaviour of the new piece. It is precisely these elements that articulate a contemporary story about an existing aff ordable house to which the General Town Planning grants expectations of buildability that did not exist before, while protecting but not cataloguing. When a Plan does not check its text against the reality of pencil on paper; when there is no jurisprudence or criterion on an ordinance in text form only, owners and architects turn to the real solution of the exercise and the faith and defence of the values that underlie its approach, through the use of exposed reinforced concrete as an ally., [ES] La experiencia que se describe se sitúa en la colonia de casas baratas Juan Canalejo de A Coruña, una de tantas colonias surgidas en la posguerra (1948) sobre la base de la Ley de Casas Baratas de 1911 y poco antes de la primera Ley del Suelo en territorio español. El interés del proyecto radica en la resolución de una Ordenanza no ensayada, justificando una actuación que no altera las condiciones ambientales de una subzona en relación a la aparición de piezas extemporáneas, a la legalidad y las expectativas del Plan que las determina. Los elementos más reconocibles del tipo se mantienen: acceso en arco que genera un zaguán (aún insertando una escalera que no existía previamente), composición de huecos y ritmo de la planta existente y conservación de la forma original de la cubierta, una cornisa que se mantiene en su lugar original –en lugar de trasladarse a la planta superior- y que ejerce de soporte del comportamiento pasivo de la nueva pieza. Son precisamente estos elementos los que articulan una historia contemporánea sobre una casa barata ya existente a la cual el Plan General le otorga unas expectativas de edificabilidad que antes no existían, al tiempo que protege pero no cataloga. Cuando un Plan no coteja su texto con la realidad del lápiz sobre el papel; cuando no existe jurisprudencia ni criterio sobre una ordenanza únicamente en forma de texto, la propiedad y los arquitectos se vuelven pioneros mediante la solución real del ejercicio y la fe y defensa de los valores que subyacen en su planteamiento, a través del uso de hormigón armado visto como aliado.