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Cálculo y diseño estructural de una nave industrial para producción de recipientes metálicos.
Get PDFEL TRABAJO FIN DE GRADO SE CENTRA EN EL CÁLCULO Y DISEÑO DE UNA NAVE INDUSTRIAL UTILIZANDO PROGRAMAS INFORMATICOS Y CON CRITERIO PROPIO APORTAR UN ALTO NIVEL DE DETALLE LA EDIFICACION. TAMBIEN, SE CENTRA EN DESARROLLAR POR MEDIO DEL ANALISIS POR ELEMENTOS FINITOS EL COMPORTAMIENTO DE LAS UNIONES.<br /
Estudio y puesta en valor de un patrimonio en riesgo: El Castillo de la Palma.
No full textEste trabajo se centra en el estudio y puesta en valor del Castillo de la Palma y su entorno, un patrimonio histórico riesgo ubicado en Sástago. La metodología de estudio se ha basado en el levantamiento arquitectónico del bien, apoyado en nuevas tecnologías como la fotogrametría, para posteriormente plantear una hipótesis reconstructiva virtual, planimétrica y en volumen, de sus diferentes etapas. Esto ha permitido realizar un análisis paisajístico y arquitectónico desde su origen musulmán a la actualidad. Finalmente, se propone un medio digital como herramienta para la difusión y conservación de este legado.<br /
Los ciclos Rankine orgánicos: estudio de mercado y análisis de ciclo de vida.
Get PDFEl presente Trabajo de Fin de Grado aborda los Ciclos Rankine Orgánicos (ORC) desde dos perspectivas principales: un estudio de mercado y un análisis de ciclo de vida (ACV). En la primera parte, se analiza la evolución y situación actual del mercado de los ORC, identificando las principales aplicaciones, fabricantes, y su distribución geográfica. En la segunda parte, se lleva a cabo un ACV del HRU-25, un ORC de 30 kWe producido por la empresa española ENERBASQUE S.L., para estimar los impactos ambientales asociados a su fase de fabricación. El estudio de mercado se fundamenta en información detallada y actualizada, obtenida gracias al acceso a la base de datos de la web https://orc-world-map.org/, proporcionado por su administrador, así como en datos adicionales recopilados directamente de dos empresas relevantes del sector, como RANK ORC S.L. y ENERBASQUE S.L. Este análisis del mercado muestra una expansión significativa en el uso de los ORC entre 2000 y 2012, con un posterior crecimiento constante hasta 2018, y un estancamiento desde el año 2019. En cuanto a las aplicaciones, el aprovechamiento de biomasa y la recuperación de calor residual lideran en número de proyectos debido a su uso en instalaciones de pequeña y mediana escala, especialmente en Europa Occidental. Por su parte, la geotermia destaca en potencia instalada, representando más del 80% del total gracias a proyectos de gran envergadura en regiones como América del Norte y Asia. Por otro lado, el ACV del ORC fabricado por ENERBASQUE S.L., se basa en datos reales proporcionados por el director de dicha empresa, lo que ha permitido modelar con rigor la fabricación del equipo. Este ACV, se ha realizado con el software SimaPro v9.5.0.2 y la base de datos Ecoinvent v3.9.1, identificando como componentes más críticos en términos de impacto ambiental el condensador, el evaporador y el regenerador, con contribuciones al calentamiento global del 20,35%, 17,27% y 18,00%, respectivamente. Además, se ha concluido que el cobre es el material con mayor impacto ambiental, debido tanto a su uso predominante como a su elevada huella asociada a los procesos de extracción y fabricación. Estos resultados han permitido establecer una base de referencia para futuras optimizaciones del diseño y la fabricación de estos sistemas.<br /
Valorization of local regional apple (Malus domestica Borkh.) cultivars versus commercial samples from Spain: Phenolic compounds by HPLC-MS/MS, cytotoxicity and biological potential on nitric oxide radicals and lipoxygenase inhibition
No full textSustainability in the fruit industry and protection of local cultivars are nowadays important tasks for consumers and authorities. Phenolic compounds are interesting to explore because they play an important role in fruit-related health benefits. The phenolic profile of the regional and commercial Spanish apple cultivars was performed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). For a deeper understanding of their anti-inflammatory and antioxidant potential, the 5-lipoxigenase inhibition and NO− scavenging were evaluated. Moreover, cellular viability was determined to perform MTT assay in HepG2 and HeLa cell lines to discard cytotoxicity. The results showed that procyanidin B2 (PB2), 3-caffeoylquinic acid, epicatechin and 4-hydroxy benzoic acid were the most abundant phenolic compounds. Autochthonous apple cultivars showed better 5-LOX/NO− inhibition and nontoxic effects in the tested cell lines with an interesting profile of phenolic compounds. Local autochthonous apples can be considered a better source of bioactive compounds than the commercial samples
Universality arising from invertible weighted composition operators
No full textA linear operator U acting boundedly on an infinite-dimensional separable complex Hilbert space H is universal if every linear bounded operator acting on H is similar to a scalar multiple of a restriction of U to one of its invariant subspaces. It turns out that characterizing the lattice of closed invariant subspaces of a universal operator is equivalent to solve the Invariant Subspace Problem for Hilbert spaces. In this paper, we consider invertible weighted hyperbolic composition operators and we prove the universality of the translations by eigenvalues of such operators, acting on Hardy and weighted Bergman spaces. Some consequences for the Banach space case are also discussed
Conformational effects in the identification and quantification of ketohydroperoxides in the oxidation of <i>n</i>-pentane
No full textStereochemistry plays a key role in both fundamental chemical processes and the dynamics of a large set of molecular systems of importance in chemistry, medicine and biology. Predicting the chemical transformations of organic precursors in such environments requires detailed kinetic models based on laboratory data. Reactive intermediates play a critical role in constraining the models but their identification and especially their quantification remain challenging. This work demonstrates, via the study of the gas-phase autoxidation of n-pentane, a typical fuel surrogate, that accounting for spatial orientation is essential for accurate characterization of such intermediates and for their further evolution. Using synchrotron-based photoelectron photoion coincidence spectroscopy and high-level quantum calculations to investigate the electronic structure and ionization dynamics of the main ketohydroperoxide isomer formed during the oxidation of n-pentane, we reveal the multiple thermally accessible conformers of the chain-branching agent, highlighting how their distinct ionization energies and fragmentation pathways can significantly affect intermediate quantification via photoionization-based probes, a universal in situ method of choice. This research underscores the importance of stereochemistry not only in combustion systems but in any chemical system where a molecular-level understanding is crucial for developing accurate predictive models for both scientific and industrial applications
Molecular ecology of novel amdoparvoviruses and old protoparvoviruses in Spanish wild carnivorans
Get PDFWild carnivorans are key hosts of parvoviruses of relevance for animal health and wildlife conservation. However, the distribution and diversity of parvoviruses among wild carnivorans are under-investigated, particularly in Southern Europe. We evaluated the presence, spread, and diversity of multi-host protoparvoviruses (canine parvovirus type 2 (CPV-2), feline panleukopenia virus (FPV)), and amdoparvoviruses in 12 carnivoran species from Northern Spain to explore viral ecology. Broad-range PCRs were used to screen spleens (N = 157) and intestines (N = 116) from 171 road-killed mustelids, viverrids, and felids; identified viruses were molecularly characterized. We detected an Asian-like CPV-2c strain in the spleen of one wildcat (Felis silvestris, 1/40, 2.5 %), a globally distributed FPV strain in the spleen of one Eurasian badger (Meles meles, 1/35, 2.9 %), a novel amdoparvovirus (European mustelid amdoparvovirus 1), in the intestine and spleen of one stone marten (Martes foina, 1/16, 6.3 %) and in the spleen of one Eurasian badger (1/35, 2.9 %), the red fox fecal amdovirus (RFFAV) in the intestine and spleen of three wildcats (3/40, 7.5 %), and a novel amdoparvovirus closely related to RFFAV (European felid amdoparvovirus 1) in one wildcat (1/40, 2.5 %). We observed a correlation between the phylogeny of carnivorans and the one of amdoparvoviruses, possibly indicating virus-host co-evolution. Species originating from North America and Eurasia formed different clades, indicating local segregation in the absence of man-linked transboundary movements. In contrast, CPV-2 and FPV strains were internationally dispersed. Different parvovirus species co-occur in sympatric host populations, and higher viral diversity and additional hosts will likely be identified in future studies
Rural Entrepreneurship in the Face of Geodemographic Challenges
Get PDFRural entrepreneurs face significant obstacles due to factors such as sparse population, low density, aging population, remoteness from markets and financial providers, inadequate infrastructure, and challenging geographic conditions. These factors contribute to rural disadvantage, fueling rural depopulation. Governments often attempt to address rural depopulation by supporting entrepreneurship, but eligibility criteria vary widely. This paper develops a model of rural entrepreneurship liability explained by municipal demographic and geographic factors. We analyzed the geographical distribution of all companies established in Spain since 2012, along with the attributes of the municipalities where they are headquartered. While working‐age municipal population is the primary factor in determining rural entrepreneurship liability, network coverage, altitude, and population variation also play noteworthy roles. Geographic constraints have a significant negative impact on entrepreneurship, but their influence is mitigated by the working‐age municipal population, highlighting the unique challenges faced by rural entrepreneurs. One policy implication of our findings is that governments could consider using this model to allocate grants based on the actual difficulty of undertaking entrepreneurship in each municipality
Three-dimensional dental topography of fossil suids and paleoenvironmental reconstruction of earliest Vallesian (Late Miocene) sites from the Vallès-Penedès Basin (NE Iberian Peninsula)
No full textThe earliest Vallesian (∼11.2 Ma) sites of Castell de Barberà (CB) and Creu de Conill 20 (CCN20), in the Vallès-Penedès Basin (NE Iberian Peninsula), are similarly well sampled but display differences in faunal composition that hint at paleoenvironmental differences. Most importantly, CB records one of the few co-occurrences of hominoids and pliopithecoids in the Miocene of Europe, while primates are seemingly absent from CCN20. Differences are also reflected in the more diverse suid assemblage from CB. To ascertain the paleoecological basis for such differences, here we investigate the diets of the suids from these sites—the suine Propotamochoerus palaeochoerus, the tetraconodontines Parachleustochoerus valentini and Versoporcus steinheimensis, and the listriodontine Listriodon splendens. We use 3D dental topography to infer paleodiet and provide further insight into the local paleoenvironmental differences between these sites. We measure four variables—orientation patch count, relief index, angularity, and mean surface slope—and distinguish herbivorous from omnivorous taxa, with the former categorized as browsers, mixed feeders, and grazers. The analyzed suids are similar in terms of angularity but differ in mean surface slope, orientation patch count and relief index. A canonical variate analysis classifies the CB and CCN20 suids as herbivorous (mixed feeders), except for P. palaeochoerus from CCN20, which displays greater similarities to omnivores (higher surface complexity), suggesting more varied diets in the latter locality. We conclude that, despite being roughly coeval and geographically close (∼10 km), these two sites record different local paleoenvironments—with CB representing a very humid and densely forested habitat, and CCN20 recording a more open, arid, and seasonal environment. This confirms previous inferences based on faunal composition and would explain the absense of primates from CCN20. Our study further highlights the relevance of local paleoenvironments for understanding differences in faunal composition among past communities from the same area
Bedload response to dam removal: Results from a 6-year particle tracking survey in the Leitzaran River (Basque Country)
Get PDFDams, weirs and transverse barriers to rivers interrupt sediment continuity and reduce sediment supply downstream. In this regard, dam removal is an increasingly used river restoration measure to recover longitudinal connectivity of sediment, among many other river processes. In this work we present a 6-year (from 2016 to 2022) monitoring of bedload transport before, during and after the removal of the 7-meters high Olloki dam in the Leitzaran River (Basque Country). The removal process started in 2018 with the upper 3 m and was completed in 2019 with the remaining 4 m of the dam. To monitor bedload transport, we seeded RFID-tagged stones in three reaches: a control reach unaffected by the dam, a reach immediately upstream of the dam, and a reach downstream of the dam. We deployed 300 tagged stones each year (100 by reach), i.e., 1800 in total. We measured important mobilization and displacement of tracer stones (with maximum travel distances of ∼8.8 km of tracers seeded upstream the Olloki dam) during an active hydrological year following the complete removal of the dam, with some tagged particles even travelling across a downstream weir. We also reported changes in the progression of tagged stones in the dam-affected reaches (upstream and downstream) with the removal, with further and faster dispersal of sediments once the dam was removed. In addition, in these reaches we estimated larger volumes of mobilized bedload in the three years following removal than in the previous years, especially in the upstream reach. In this regard, the relationship between bedload and cumulated energy suggests that less energy was expended in the upstream reach for mobilizing bedload once the removal of the dam was completed. Conversely, in the control reach no major changes were observed before and after the removal of the dam; this reach showed only an increase in sediment mobilization during the last hydrological year, which was the most hydrologically active of the whole monitoring period. In summary, our tracer observations document that travel distances and mobilization volumes are considerably increased with dam removal, especially once the dam was completely removed