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Exploring Perhydro-Benzyltoluene Dehydrogenation Using Sulfur-Doped PtMo/Al2O3 Catalysts
No full textThis study investigates the dehydrogenation of perhydrobenzyltoluene, a Liquid Organic Hydrogen Carrier (LOHC), using sulfur-doped bimetallic PtMo/Al2O3 catalysts. Based on previous research that highlighted the superior performance of PtMo catalysts over monometallic Pt catalysts, this work focuses on minimizing byproduct formation, specifically methylfluorene, through sulfur doping. Catalysts with low platinum content (<0.3 wt.%) were synthesized using the wet impregnation method by varying sulfur concentrations to study their impact on catalytic activity. Characterization techniques, including CO–DRIFT and CO–TPD, revealed the role of sulfur in selectively blocking low-coordinated Pt sites, thus improving selectivity and maintaining high dispersion. Catalytic tests revealed that samples with ≥0.1 wt.% sulfur achieved up to a threefold reduction in methylfluorene formation compared to the unpromoted PtMo/Al2O3 sample, with a molar fraction below 2% at 240 min. In parallel, these samples reached a degree of dehydrogenation (DoD) above 85% within 240 min, demonstrating that improved selectivity can be achieved without compromising catalytic performance.This research was supported by the University of the Basque Country (UPV/EHU), Basque Government (Project: IT1554-22), and Clean Hydrogen Partnership (grant agreement: 101111964). This Joint Undertaking receives support from the European Union’s Horizon 2020 research and Innovation programme, Hydrogen Europe, and Hydrogen Europe research. Grant PID2020-112889RB-I00 was funded by MCIN/AEI/10.13039/501100011033
PTML models of self assembled ligand free nanoparticle catalysts for cross coupling reactions
No full textCross-coupling reactions have transformed the synthesis of complex and valuable compounds used in pharmaceuticals, materials science, and chemical synthesis. Transition metal nanoparticle (NP) catalysts represent a promising strategy within this field, but their behavior and efficiency continue under investigation. The use of computational models enables rapid design, optimization, and understanding of the behavior of these molecules, thereby reducing the costs and time. In this study, the perturbation theory and machine learning (PTML) approach was used to construct a predictive model for estimating yield after multiple reuses (up to 10) of self-assembled Au- or glass-supported transition metal NP catalysts under ligand-free conditions and diverse cross-coupling reactions. The studied reactions include Suzuki–Miyaura, Kumada, Negishi, Buchwald-Hartwig, C(sp2)- and C(sp3)-H functionalization, and double carbonylation. A comprehensive dataset was built, and multiple linear regression (MLR) and artificial neural network (ANN) models were built and compared. The best MLR model achieved MAE = 7.4% and RMSE = 12.2% on the test set, demonstrating robust performance for yield prediction. Among the ANN models, MLP (9:9-20-9-1:1) and RBF (9:9-70-1:1) regression models showed similar results, with test MAE of 5.9% and 5.8% respectively, and both showed test RMSE of 9.8%. MLP (9:9-20-18-1:1) classification model showed high precision (97.0%) and recall (93.8%), effectively distinguishing high- and low-yielding reactions. These results highlight the potential of PTML-based models to guide catalyst and reaction condition selection, optimize catalytic systems, and minimize synthesis costs and environmental impact.KERDATA S.L. INVESTIGO program grant (2022/IKER/000040), funded by LANBIDE and European Commission, NextGenera-tionEU, Grant PID2022-137365NB-100 (2023-2026) funded by MCIN/AEI/10.13039/501100011033, and ELKARTEK 2022 grant (KK-2022/00032) and IT1558-22 grant (2022-2025), funded by Basque Government/Eusko Jaurlaritza
Sex differences in jump capacity and elastic index in table tennis players
No full textBackground/Aims: Table tennis performance is influenced by various factors such as technique, tactics, and fitness. Additionally, many shots are executed at high speeds, developing significant levels of explosive strength in the lower extremities. This study aimed to assess the jump capacity and the elasticity index of the lower limbs among young table tennis players based on sex. Additionally, this study assessed leg asymmetries between the dominant and non-dominant limbs during jump tests. Methods: A total of 40 players (20 boys and 20 girls), aged 16–18 years, participated in the study. Vertical countermovement jump, squat jump, and horizontal jump tests were conducted to evaluate both vertical and horizontal jumping capacities, as well as leg asymmetries between the dominant and non-dominant limbs. Results: Differences were observed in both vertical and horizontal jumps, with male players achieving better results in all jumping capacities. However, female players obtained better values in elastic index. Additionally, significant differences were found between dominant and non-dominant legs in both male and female players. Conclusions: Considering that explosive strength is one of the most essential physical capacities in this sport, this information could prove valuable for talent identification, the design of training programs, and the optimization of physical performance monitoring systems in table tennis
Impact analysis of DLR systems with forecasting on economic benefits and renewable generation curtailments
No full textThis article studies the benefits obtained from the use of overhead line dynamic line rating (DLR) systems in the operation and scheduling of the electricity market. The use of these systems makes it easier to operate the network more efficiently in real time and allows the use of different thermal limits when scheduling the electricity market (market ratings). When an overhead line is congested, congestion can be reduced by using static probabilistic ratings and probabilistic forecasted ratings, which are associated with a risk of overestimating ampacity. This risk level of overestimated ampacity is related to the risk that the real ampacity is less than the given value on the market. There will be an optimal overestimation risk of ampacity for each system, and changing the system conditions will alter the optimal risk to be assumed within the market limits from an economic perspective. The generation profile in the system influences the needs of the overhead transmission line, as well as the benefits obtained from such systems. To analyse how the optimum risk varies, two cases are simulated in the IEEE 24-bus network. The results show that the type of renewable generation on the grid influences the needs of the overhead line and the optimal risk to obtain an economic benefit.This work is financially supported by the Grant TED2021-129930A-I00 funded by MICIU/AEI/10.13039/501100011033 and by the “European Union NextGenerationEU/PRTR”; by the Grant PID2021- 125881OB-I00 funded by MICIU/AEI/10.13039/501100011033 and by “ERDF/EU”; and by the Basque Government under the Grant IT1647- 22 (ELEKTRIKER research group)
Adaptive engine for Formula 1
No full textEl motor adaptativo es un motor convencional mejorado con la capacidad de almacenar aire comprimido para su uso posterior en situaciones de alta demanda de potencia. Aunque su impacto en vehículos comerciales ya ha sido estudiado, este documento analiza el rendimiento del motor adaptativo en un escenario real de carrera de Fórmula 1. Los datos de velocidad de la carrera se utilizan para estimar las condiciones de funcionamiento del motor mediante un programa de simulación. Los resultados muestran que el consumo de combustible se reduce a un tercio en comparación con los motores estándar de Fórmula 1, lo que conlleva una reducción significativa de las emisiones de gases y del volumen total del motor
Aliased beating helix induced by dual-frequency vibrations in turning
No full textMachine-tool forced vibrations can generate undesired periodic patterns on the workpiece surface. These helix patterns imply poor surface quality but are valuable for identifying the machine-tool frequencies at fault as well. Thus, mathematical relations between the helix spatial features and the tool vibration frequency are fundamental for the diagnosis. This study investigates the interaction of two distinct vibration frequencies in turning and their influence on the surface. The beating phenomenon and the stroboscopic sampling of the rotary workpiece are applied to derive the aliased beating helix features. The proposed mathematical relations are numerically and experimentally validated in cylindrical turning tests.This work has been partially supported by FAUSTO (PLEC2024–011113) project funded by Transmissions call of CDTI
Recopilación y análisis de datos de trafico de servicios potencialmente vulnerables para el desarrollo de paneles de monitorización en entornos de seguridad de redes.
No full textEn los últimos años, el rápido crecimiento de infraestructuras de telecomunicaciones distribuidas ha impulsado el despliegue de redes y equipamiento en ubicaciones remotas, lo cual ha generado una creciente necesidad de administrar de forma remota sistemas y equipos críticos.
Esta situación, ha fomentado la adopción de múltiples servicios, herramientas y protocolos de administración remota, logrando asi la operación, supervisión y mantenimiento de redes sin requerir intervención física directa.
Sin embargo, este nuevo escenario también ha traído consigo importantes desafíos en términos de ciberseguridad, pues muchos de los servicios de administración remota utilizados deben ser expuestos de forma pública para su utilización, y supervisar los accesos realizados a estos no siempre es una tarea sencilla.
Ante este nuevo escenario, el objetivo principal de este Trabajo Fin de Master (TFM) es el diseño e implementación de una herramienta de monitorización que permita supervisar los servicios de administración remota expuestos públicamente, así como los accesos realizados a los mismos. Esta herramienta tiene como propósito facilitar el seguimiento continuo de estos servicios, permitiendo detectar patrones de uso, identificar posibles intentos de acceso no autorizados y contribuir a la mejora general de la ciberseguridad.Recently, the rapid growth of distributed telecommunications infrastructures has driven to the deployment of networks and equipment in remote locations, which has created an increasing need to remotely manage critical systems and equipment. This situation has fostered the adoption of multiple services, tools, and remote management protocols, enabling the operation, supervision, and maintenance of networks without requiring direct physical intervention.
However, this new scenario has also brought significant challenges in terms of cybersecurity since many of the remote administration services used need to be exposed publicly and normally accesses done to them can’t be easily supervised.
In response to this new scenario, the main objective of this Master's Thesis (MT) is to design and implement a monitoring tool that allows the effective supervision of the remote administration services exposed publicly, as well as the access to these services. The purpose of this tool is to facilitate continuous monitoring of these services, enabling the detection of usage patterns, identifying potential unauthorized access attempts, and contributing to the improvement of security.Azken urteotan banatutako telekomunikazio-azpiegituren hazkunde azkarrak urruneko kokapenetan sareak eta ekipamendua hedatzea bultzatu du eta horrek, sistema eta ekipo kritikoak urrunetik administratzeko beharra areagotu du. Egoera horrek urruneko administrazioko zerbitzu, tresna eta protokolo ugari hartzea sustatu du eta, horrela, sareak gainbegiratzea eta mantentzea lortu da, zuzeneko esku-hartze fisikorik behar izan gabe.
Egoera berri hau erronka handiak ekarri ditu zibersegurtasunari dagokionez, erabilitako urruneko administrazioko zerbitzu asko publikoki azaldu behar direlako, eta horietara egindako sarbideak gainbegiratzea ez da beti lan erraza.
Master Amaierako Lan (MAL) honen helburu nagusia monitorizazio-tresna bat diseinatzea eta inplementatzea da, publikoki ikusgai dauden urruneko administrazioko zerbitzuak eta horietarako egindako sarbideak eraginkortasunez gainbegiratzea ahalbidetzen duena. Tresna honen helburua da zerbitzu horien etengabeko jarraipena erraztea, erabilera-ereduak detektatzeko, baimendu gabeko sarbide-saiakerak identifikatzeko eta segurtasuna hobetzen laguntzeko
Lengua y política durante el tardofranquismo. El Informe sobre la lengua catalana (1970)
No full textLengua, nación y estado son conceptos sujetos a múltiples debates a lo largo de la historia. El franquismo, pese a algunas voces discordantes, optó por una lengua, una nación única y un renovado Estado Español de carácter centralista. Sin embargo, con el paso de los años, no pudo evitar el renacimiento de las lenguas y culturas consideradas regionales. Un joven y brillante intelectual mallorquín residente en Madrid, Josep Melià Pericàs (1939-2000), intentará ampliar los márgenes de tolerancia del Régimen hacia la lengua catalana. Tras chocar frontalmente con la censura en dos ocasiones conseguirá publicar una obra excepcional, el Informe sobre la lengua catalana (1970). Desde la aceptación previa de una españolidad muy plural, Melià propugna la diferenciación entre estado y nación, entre comunidad política y comunidad cultural. Además, propone medidas para normalizar progresivamente la presencia de los idiomas no oficiales de España en los ámbitos en los que estaban marginados
Una mirada posliteraria a la Capitalidad Europea de la Cultura: entre el branding y building nacional
No full textEn este artículo se abordan los principales eventos de capitalidades culturales europeas y, en concreto, la situada en 2016 en la ciudad de Donostia–San Sebastián. Este mecanismo designa una ciudad anfitriona encargada de organizar un programa de actos culturales y los beneficios esperados para las ciudades acogedoras pueden resumirse en dos vertientes: fomento de la cultura entre su ciudadanía y proyección internacional de la ciudad. Esto los sitúa en un plano cercano al capitalismo transestético en tanto que comparten tres características tales como imagen de la ciudad, participación ciudadana, como proponen Beatriz García Tamsin Cox, y vitalidad cultural, que permitirían plantear el encaje de estos eventos dentro de un régimen poscultural, en el que funcionan como place y national branding. En estos eventos, tiene su lugar, además, el patrimonio literario del lugar, mediante recorridos literarios o productos comerciales. Esto, relacionado con lo anterior, nos lleva a considerarlo dentro de una estrategia posliteraria
Bullying-aren eta pisuaren arteko harremana: Kausa-efektuaren noranzko biko berrikuspen bibliografikoa
No full textSarrera: Haur obesitatea eta eskola-jazarpena bereziki larriak diren egoerak bilakatzen ari dira. Haurtzaroan nahiz nerabezaroan bullyinga jasateak, luzaroan kalte fisiko, psikologiko nahiz sozialak eragin ditzake. Aldiz, obesitatea izateak bullyinga jasateko arriskua aztertzen duten lanak ere badaude. Bullyinga osasun publikoko arazoa kontsideratzen dela kontuan harturik, lan honetan bi norabiteak aztertuko dira.
Helburuak: Lan honen helburu nagusia bullyingaren eta haur gainpisua edo obesitatearen arteko erlazioa aztertzea izan da.
Metodologia: Berrikuspen bibliografiko hau 2024ko azarotik 2025eko otsailera arte garatu zen. Pubmed, Web of Science, Psyinfo, BVS eta Dialnet datu-baseak erabili ziren. Aurretik definitutako barneratze- eta kanporatze-irizpideak aplikatuz 29 artikulu aukeratu ziren berrikuspena burutzeko.
Emaitzak: Lan honetan bullyingaren eta gainpisuaren eta obesitatearen arteko erlazioa aztertu zen. Alde batetik, gainpisua izateak bullyinga jasateko arriskua zenbatean handitzen duen ikusi zen. Eta bestetik, bullyinga jasateak nerabezaro nahiz helduaroan obesitatea garatzearekin zein lotura duen ikertu zen. Honen guztiaren analisia eginik, erlazio honetan parte-hartzen zuten aldagai psikologiko eta biologikoak ere barnebildu ziren.
Ondorioak: Obesitatea nahiz gainpisua izatea bullyinga jasateko arriskua handitzen duela ikertua izan den arren, alderantzizko norabidea ikerketa lerro berria da oraindik. Hau da, bullyinga jasatea, obesitatea nahiz gainpisua garatzeko arriskua handitzen duela ere ikusten ari da. Erlazioetako bakoitzean eragina duten faktoreak aztertzeaz gain, noranzko biko kausa-efektuaren arteko erlazioa ezartzearen garrantzia ondorioztatu da, jazarpen mota honen larritasuna azpimarratze aldera. (Euskara