Molecular modification of coumarin dyes for more efficient dye sensitized solar cells

solo para uso personalIn this work, new coumarin based dyes for dye sensitized solar cells (DSSC) have been designed by introducing several substituent groups in different positions of the NKX-2311 structure. Two types of substitutions have been considered: the introduction of three electron-donating groups (–OH, –NH2, and –OCH3) and two different substituents with steric effect: –CH2–CH2–CH2– and –CH2–HC=CH–. The electronic absorption spectra (position and width of the first band and absorption threshold) and the position of the LUMO level related to the conduction band have been used as theoretical criteria to evaluate the efficiency of the new dyes. The introduction of a –NH2 group produces a redshift of the absorption maximum position and the absorption threshold, which could improve the cell efficiency. In contrast, the introduction of –CH2–CH2–CH2– does not modify significantly the electronic structure of NKX-2311, but it might prevent aggregation. Finally, –CH2– HC=CH– produces important changes both in the electronic spectrum and in the electronic structure of the dye, and it would be expected as an improvement of cell efficiency for these dyes.Ministerio de Ciencia e Innovación de España-MAT2008-4918 y CSD2008-002

Aplicación de herramientas Lean Manufacturing en la línea de producción de pantalones para mejorar la productividad en el área de confección, en la empresa consorcio textil exportador SAC. San Borja 2017

El presente trabajo de tesis titulado: “Aplicación de herramientas lean manufacturing en la línea de producción de pantalones para mejorar la productividad en el área de confección en la empresa Consorcio Textil Exportador S.A.C, San Borja 2017”, tuvo como objetivo general determinar en qué medida la aplicación de herramientas lean manufacturing en la línea de producción de pantalones mejorará la productividad en el área de confección en la empresa Consorcio Textil Exportador S.A.C. San Borja 2017, Al respecto, Hernández y Vizan, sostiene que la utilización de herramientas lean manufacturing se usan para quitar cualquier cosa que le quitan valor al producto, las herramientas usadas son el Value Stream Mapping y la evaluación de las 5S. Así mismo Cruelles, para medir la productividad se debe considerar que la eficacia es el cumplimiento de las metas con la utilización más optima de los recursos y la eficacia es el cumplimiento de los objetivos trazados. El diseño del estudio es cuasi experimental. La población fue la producción diaria de pantalones. La muestra fue igual que la producción, el instrumento fue la ficha de recolección de datos y reporte de tiempos por cada operación juntamente con la ficha de evaluación de las 5S. Al finalizar el presente estudio se obtuvieron los resultados iniciales de eficiencia de 23% y 28% finales, eficacia inicial de 55% y 82% final, productividad inicial de 13% y 23% final, se llegó a la conclusión que la aplicación de herramientas lean manufacturing mejoró la productividad en 43% en la producción de pantalones, lo cual es favorable para el área de confecciones de la empresa

Análisis de la evolución de los Repositorios Institucionales de material educativo digital de las universidades españolas

Los Repositorios de Material Educativo Digital permiten que profesores y estudiantes puedan almacenar y recuperar fácilmente sus recursos educativos para usarlos en los actuales entornos de aprendizaje virtual y presencial. Asimismo, constituyen un mecanismo eficaz para difundir y valorar la calidad de la producción didáctica de los profesores. Finalmente, se consideran un indicador del uso excelente de las Tecnologías de la Información y las Comunicaciones en la docencia de las instituciones educativas. El objetivo del presente estudio es explorar el grado en que las universidades españolas cumplen actualmente el criterio de la excelencia consistente en tener repositorios educativos y el modo en el que éstos han evolucionado a lo largo de estos años. Se espera que las conclusiones derivadas del análisis puedan contribuir al diseño de estrategias dirigidas a la promoción de la creación y el uso de materiales educativos digitales de alta calidad en España

Herramienta para la revisión de la Calidad de Objetos de Aprendizaje Universitarios (COdA): guía del usuario. v.1.1

Guía para la revisión de la calidad de los objetos de aprendizaje dirigida a los autores para que puedan mejorar sus OA y además pueda ser utilizada por los revisores externos cuando los autores deseen o necesiten un reconocimiento o certificado de calidad para sus colecciones de OA. La herramienta COdA ha sido desarrollada en el marco del Proyecto de Innovación y Mejora de la Calidad de la Docencia -PIMCD 268/2010-2011. “Un repositorio digital educativo para la Facultad de Filología”- financiado por el Vicerrectorado de Desarrollo y Calidad de la Docencia de la Universidad Complutense de Madrid. COdA se ha basado en el modelo LORI desarrollado por el E-Learning Research and Assessment Network (eLera) y el Portal for Online Objects in Learning (POOL)

Convolutional Neural Network Predictions for Unsteady Reynolds-Averaged Navier–Stokes-Based Numerical Simulations

The application of computational fluid dynamics (CFD) to turbulent flow has been a considerable topic of research for many years. Nonetheless, using CFD tools results in a large computational cost, which implies that, for some applications, CFD may be unviable. To date, several authors have carried out research applying deep learning (DL) techniques to CFD-based simulations. One of the main applications of DL with CFD is in the use of convolutional neural networks (CNNs) to predict which samples will have the desired magnitude. In this study, a CNN which predicts the streamwise and vertical velocities and the pressure fields downstream of a circular cylinder for a series of time instants is presented. The CNN was trained using a signed distance function (SDF), a flow region channel (FRC) and the t-1 sample as inputs, and the ground-truth CFD data as the output. The results showed that the CNN was able to predict multiple time instants with low error rates for turbulent flows with variable input velocities to the domain.The current study was sponsored by the Government of the Basque Country-ELKARTEK21/10 KK-2021/00014 and IT1514-22 research program

Injertos osteocondrales congelados en el conejo: Estudio experimental

Con el propósito de analizar un protocolo de congelación de cartílago completo estudiando y la viabilidad del cartílago tas la implantación se ha realizado un estudio experimental en 60 rodillas de 45 conejos de Nueva Zelanda en población no genéticamente pura. Se extrajeron injertos osteocartilaginosos de 4 mm de diámetro y 2-3 mm de espesor, incluyendo cartílago articular y hueso subcondral que fueron sometidos a congelación lenta hasta -196º en Planer Kryo-10, Serie II, Controlled Rate Freezers, siguiendo un descenso de temperatura controlada bajo crioprotección con Dimetilsulfóxido, propanodiol y sacarosa. Posteriormente fueron descongelados e implantados en cóndilos femorales. Los injertos evolucionaron a tejido amorfo acelular y pasados los 2 meses, tras la incorporación del componente óseo se desarrolló tejido ibrocartilaginoso de sustitución. El presente estudio indica que el cartílago articular congelado no mantiene su viabilidad tras la implantación.The purpose of this study was to analyze a protocol for freezing whole cartilage and to study the viability of cartilage after the implant in 60 knees of 45 New Zealand rabbits from a genetically impure population. Osteocartilaginous implants were removed, measuring 4 mm in diameter and 2-3 mm thickness, inclunding the articular cartilage and the suchondral bone, and slow freezing up -196º using Planer Kyro-10, Series II, Controlled Rate Freezers, following a controlled drop in temperature under cyrso-protection with Dimethylsulfoxide, propanediol and sacarose. After thawing grafts were implanted in femoral condyles. The implants evolves into an acellular amorphous tissue and after 2 months, period in which the incorporation of the osseous compound occurs, substitute fibrocartilaginous tiusse develops. This study shows that frozen articular cartilage does not remain viable after implant

Neuroprotective Effects of Resveratrol in Ischemic Brain Injury

Cerebral ischemia represents the third cause of death and the first cause of disability inadults. This process results from decreasing cerebral blood flow levels as a result of the occlusionof a major cerebral artery. This restriction in blood supply generates low levels of oxygen andglucose, which leads to a decrease in the energy metabolism of the cell, producing inflammation, andfinally, neurological deterioration. Currently, blood restoration of flow is the only effective approachas a therapy in terms of ischemic stroke. However, a significant number of patients still have apoor prognosis, probably owing to the increase in the generation of reactive oxygen species (ROS)during the reperfusion of damaged tissue. Oxidative stress and inflammation can be avoided bymodulating mitochondrial function and have been identified as potential targets for the treatmentof cerebral ischemia. In recent years, the beneficial actions of flavonoids and polyphenols againstcerebrovascular diseases have been extensively investigated. The use of resveratrol (RSV) has beenshown to markedly decrease brain damage caused by ischemia in numerous studies. According toin vitro and in vivo experiments, there is growing evidence that RSV is involved in several pathways,including cAMP/AMPK/SIRT1 regulation, JAK/ERK/STAT signaling pathway modulation, TLR4signal transduction regulation, gut/brain axis modulation, GLUT3 up-regulation inhibition, neuronalautophagy activation, and de novo SUR1 expression inhibition. In this review, we summarize therecent outcomes based on the neuroprotective effect of RSV itself and RSV-loaded nanoparticlesin vitro and in vivo models focusing on such mechanisms of action as well as describing the potentialtherapeutic strategies in which RSV plays an active role in cases of ischemic brain injuryFil: Machado, Noelia Daiana. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina. Universidad Nacional de Córdoba. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada; ArgentinaFil: Villena Armas, Gorka. Universidad de la Laguna. Departamento de Química Orgánica. Instituto Universitario de Bio-Orgánica "Antonio González"; EspañaFil: Fernández, Mariana Adela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; ArgentinaFil: Grijalvo, Santiago. Institute For Advanced Chemistry Of Catalonia; España. Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine; EspañaFil: Díaz Díaz, David. Universidad de la Laguna. Departamento de Química Orgánica. Instituto Universitario de Bio-Orgánica "Antonio González"; España. Universitat Regensburg; Alemani

Pollutant emissions from Euro 6 light duty vehicle tested under steady state and transient operation on a roller test bench with hydrogenated paraffinic and biodiesel fuels

[EN] The effort to implement more environmental-friendly fuels has been enhanced not only by the desire to reduce the greenhouse effects but also for public health issues. This paper studies the effects on pollutant emissions from a light-duty Euro 6 vehicle with four types of fuel: diesel (fossil origin, used as reference), biodiesel (renewable origin), Gas-to-Liquid (fossil origin) and farnesane (renewable origin). Both stationary engine and real-world driving cycles are studied. First, each fuel was tested in stationary modes in a vehicle test-bench and then tested in a realistic driving cycle with the same vehicle. This allows the separation the transient effects of the driving cycle from stationary results. Stationary tests lead to engine emission maps and driving cycle tests allow weighting the importance of each stationary condition during a realistic route. Instantaneous and cumulative CO, THC (total hydrocarbon), NOx and PN (particle number) emissions on route were obtained. The fuel that presented a highest level of emissions at stationary conditions was, for CO, diesel, for THC, diesel, for NOx, biodiesel and for PN, diesel. The behaviour of fuels during the driving cycles, from less pollutant to more pollutant, was: for CO, diesel, farnesane, GTL and biodiesel; for THC, GTL, farnesane, biodiesel, diesel. For NOx, farnesane and diesel (very similar values), GTL and biodiesel; for PN, GTL, biodiesel, farnesane and diesel.The authors would like to thank the funding provided by the Spanish Ministry of Science for RECUPERA project (Ref. RTI2018-095923-B-C21) and infrastructure (Ref. EQC2019-005675-P) , the donation of Farnesane fuel by AMYRIS, the donation of GTL fuel by SASOL and the discount provided by REPSOL in the purchase of diesel and biodiesel fuels.Fernández-Yáñez, P.; Soriano, JA.; Soto, F.; Armas, O.; Pla Moreno, B.; Bermúdez, V. (2022). Pollutant emissions from Euro 6 light duty vehicle tested under steady state and transient operation on a roller test bench with hydrogenated paraffinic and biodiesel fuels. Fuel. 323:1-12. https://doi.org/10.1016/j.fuel.2022.12417311232

A CFD Modelling Approach for the Operation Analysis of an Exhaust Backpressure Valve Used in a Euro 6 Diesel Engine.

Harvesting residual thermal energy from exhaust gases with thermoelectric generators is one of the paths that are currently being explored to achieve more sustainable and environmentally friendly means of transport. In some cases, thermoelectric generators are installed in a by-pass configuration to regulate the mass flow entering the thermoelectric generator. Some manufacturers are using throttle valves with electromechanical actuators and electronic control in the exhaust pipe to improve techniques for active control of pollutant emissions in reciprocating internal combustion engines, such as the exhaust gas recirculation. The above-mentioned circumstances have motivated the approach of this work: computational fluid dynamics (CFD) modelling of the operation of a throttle valve used for establishing adequate exhaust backpressure conditions to achieve the low pressure exhaust gas recirculation in Euro 6 engines. The aim of this model is to understand the flow control process with these types of valves in order to incorporate them in an exhaust system that will include two thermoelectric generators used to convert residual thermal energy into electrical energy. This work presents a computational model of the flow through the throttle valve under different temperatures and mass flow rates of the exhaust gas with different closing positions. For all cases, the values of the pressure drop were obtained. In all cases studied, the level of agreement between the modelled and experimental results exceeds 90%. The developed model has helped to propose a correlation to estimate the mass flow rate of exhaust gas from easily measurable quantitiesPartial funding for open access charge: Universidad de Málag