High-temperature infrared emissivity of materials for alternative energy applications

xxv, 171 p.La emisividad es una propiedad termofísica que relaciona la cantidad de radiación térmica que emite un material con la radiada por un cuerpo negro. Se trata de una propiedad de gran importancia en ámbitos industriales y científicos, ya que condiciona las transferencias de calor en situaciones de alta temperatura o alto vacío. La presente tesis se divide en dos apartados fundamentales: por una parte, el desarrollo y mejora de métodos de medida de emisividad y, por otra, la aplicación de dichos métodos a la caracterización de materiales de interés industrial en el sector de las energías alternativas (solar térmica y nuclear de fusión). En primer lugar, se ha llevado a cabo una profunda revisión del aparato singular de medida de emisividad en la UPV/EHU, incluyendo mejoras instrumentales y metodológicas, así como un renovado análisis de sus fuentes de error. En segundo lugar, se han estudiado tres tipos de materiales: absorbentes solares selectivos multicapa para centrales solares térmicas de tubo, recubrimientos negros no selectivos para centrales de torre y una familia de aleaciones de vanadio para futuros reactores nucleares de fusión. El objetivo global de este trabajo es mejorar nuestro conocimiento sobre las propiedades de transferencia de calor por radiación de materiales clave para estos procesos energéticos alternativo

High-temperature infrared emissivity of materials for alternative energy applications

xxv, 171 p.La emisividad es una propiedad termofísica que relaciona la cantidad de radiación térmica que emite un material con la radiada por un cuerpo negro. Se trata de una propiedad de gran importancia en ámbitos industriales y científicos, ya que condiciona las transferencias de calor en situaciones de alta temperatura o alto vacío. La presente tesis se divide en dos apartados fundamentales: por una parte, el desarrollo y mejora de métodos de medida de emisividad y, por otra, la aplicación de dichos métodos a la caracterización de materiales de interés industrial en el sector de las energías alternativas (solar térmica y nuclear de fusión). En primer lugar, se ha llevado a cabo una profunda revisión del aparato singular de medida de emisividad en la UPV/EHU, incluyendo mejoras instrumentales y metodológicas, así como un renovado análisis de sus fuentes de error. En segundo lugar, se han estudiado tres tipos de materiales: absorbentes solares selectivos multicapa para centrales solares térmicas de tubo, recubrimientos negros no selectivos para centrales de torre y una familia de aleaciones de vanadio para futuros reactores nucleares de fusión. El objetivo global de este trabajo es mejorar nuestro conocimiento sobre las propiedades de transferencia de calor por radiación de materiales clave para estos procesos energéticos alternativo

Propiedades radiativas y ópticas de una herramienta de corte compuesta por nitruro de boro cúbico

Se ha medido la emisividad espectral (2,5-25 micras) normal de una herramienta de corte industrial, compuesta en un 55% por nitruro de boro cúbico (cBN), en el rango de temperaturas 200-1000 ºC. La emisividad medida muestra un comportamiento suavemente descendente al aumentar la longitud de onda, propio de metales, con un descenso pronunciado alrededor de 9 micras. Este valle se corresponde con la emisividad calculada para el cBN cúbico puro en la literatura, que sin embargo no exhibe el comportamiento metálico medido. Así mismo, se observa que la emisividad espectral es esencialmente independiente de la temperatura, aunque no así la emisividad total. Los resultados experimentales para el cBN puro indican que la reflectividad de dicho compuesto se puede explicar satisfactoriamente mediante un modelo de Lorentz para dieléctricos, mientras que el ajuste teórico de la reflectividad medida para la herramienta de corte necesita incluir una contribución del modelo de Drude para explicar el comportamiento metálico observado. Este modelo combinado se ajusta razonablemente bien a las medidas, y revela que la herramienta de corte se comporta como un semiconductor degenerado, con una alta densidad de portadores libres. Además, permite realizar una estimación teórica de sus constantes ópticas. Por último, se ha realizado un estudio sobre la medida y el control de la temperatura de la muestra, empleando distintos métodos de unión termopar

Experimental and numerical study of the emissivity of rolled aluminum

Directional spectral emissivity measurements on a rolled aluminum sheet are reported between 423 and 823 K in vacuum. The results are compared to available literature data and to theoretical predictions, revealing the crucial role of the surface state in explaining the observed scatter of values. In particular, it is argued that the cold-rolling process induces a multi-scale roughness profile that significantly enhances emission at all wavelengths, a phenomenon that can be described using rigorous coupled-wave analysis (RCWA). A small peak in the p-polarized component at oblique angles is formed by the native oxide layer. Aside from the intrinsic value of the emissivity data for the application of thermographic techniques to rolled aluminum materials, the results contained in this work also serve to validate the usefulness of RCWA to simulate the emissivities of randomly rough metal surfaces, highlighting directions of further research.This work was funded by the University of the Basque Country, Spain (GIU19/019) and the Basque Government, Spain (IT-1714-22 and PIBA-2021-1-0022). J. Gabirondo-López and I. González de Arrieta also acknowledge financial support from pre- and post-doctoral fellowships by these institutions (University of the Basque Country, Spain: PIF 21/06; Basque Government, Spain : POS-2021-2-0022). Technical support was provided by the SGIker service of UPV/EHU for the XPS analysis. Finally, the authors thank Jordan Edmunds for assistance with the RCWA code

P3-062: Wood-smoke exposure as a survival predictor in non-small cell lung cancer with response to erlotinib: an open label phase II study

This paper explores the opportunity for New Zealand to establish and sustain an internationally competitive sheep dairy industry. As part of this it evaluates the role of responsible innovation (RI) within the New Zealand sheep dairy (NZSD) industry and whether this can assist in achieving a sustainable competitive advantage. In the context of agrifood supply chains RI has received little attention despite the fact that these industries have significant environmental, ethical and social impacts. The research also addresses the lack of evidence as how to put RI into practice and the claim that the practical applicability of RI is not possible. The French sheep dairy industry was used as a comparative case study for the New Zealand industry. Information was gathered through a literature search, the comparative case study and interviews with New Zealand and French industry experts. Comparisons were made between the strategic capabilities and structural forces of the sheep dairy industries in both France and New Zealand. The study found that for the NZSD industry to achieve a competitive advantage it would need to pursue a differentiation strategy that focused on customer responsiveness, innovation, sustainability and quality. Furthermore, the study identified that RI had the potential to assist the NZSD industry by providing distinctive competencies to develop a competitive advantage. This is because there were existing resources and capabilities that provided a platform for differentiation. There were also strategic and economic drivers in the NZSD industry that encouraged RI as a competitive strategy. This indicated that for RI to occur there needed to be economic incentives that encouraged companies to pursue this strategy

Finanças públicas, direito financeiro e direito tributário em tempos de pandemia: diálogos ibero-americanos

- Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.- Localização na estante: 347.73:578.834(7/8) F491p- Organizado por: Carlos Palao Taboada, Germán Orón Moratal, João Ricardo Catarino, José Casalta Nabais, Juan Arrieta Martinez de Pisón e Marciano Seabra de Godoi

Propuesta de un manual de procesos de selección del personal de la empresa Inversiones Villa del rio 36 SAS para el año 2021

La empresa Villa del Rio 36 SAS fue fundada el 29 de agosto del 2018, ubicada en la ciudad de Valledupar es una empresa dedicada a la fabricación de productos derivados de la leche, cuenta actualmente 17 empleados. El motivo de este proyecto es proponer un manual de procesos de selección de personal, puesto que, por su temprana edad la empresa presenta escasez de herramientas de gestión en el área de talento humano, que permitan realizar un proceso de selección de personal y de esta manera contar con personal idóneo para el mantenimiento y crecimiento de la organización.The company Villa del Rio 36 SAS was founded on August 29, 2018, located in the city of Valledupar is a company dedicated to the manufacture of products derived from milk, currently has 17 employees. The reason for this project is to propose a manual of personnel selection processes, due to the fact that due to its early age the company lacks management tools in the area of human talent that allow it to carry out a personnel selection process and, in this way, count on with suitable personnel for the maintenance and growth of the organization

A long-lasting porcine model of ARDS caused by pneumonia and ventilator-induced lung injury

Background: Animal models of acute respiratory distress syndrome (ARDS) do not completely resemble human ARDS, struggling translational research. We aimed to characterize a porcine model of ARDS induced by pneumonia—the most common risk factor in humans—and analyze the additional effect of ventilator-induced lung injury (VILI). Methods: Bronchoscopy-guided instillation of a multidrug-resistant Pseudomonas aeruginosa strain was performed in ten healthy pigs. In six animals (pneumonia-with-VILI group), pulmonary damage was further increased by VILI applied 3 h before instillation and until ARDS was diagnosed by PaO2/FiO2 &lt; 150 mmHg. Four animals (pneumonia-without-VILI group) were protectively ventilated 3 h before inoculum and thereafter. Gas exchange, respiratory mechanics, hemodynamics, microbiological studies and inflammatory markers were analyzed during the 96-h experiment. During necropsy, lobar samples were also analyzed. Results: All animals from pneumonia-with-VILI group reached Berlin criteria for ARDS diagnosis until the end of experiment. The mean duration under ARDS diagnosis was 46.8 ± 7.7 h; the lowest PaO2/FiO2 was 83 ± 5.45 mmHg. The group of pigs that were not subjected to VILI did not meet ARDS criteria, even when presenting with bilateral pneumonia. Animals developing ARDS presented hemodynamic instability as well as severe hypercapnia despite high-minute ventilation. Unlike the pneumonia-without-VILI group, the ARDS animals presented lower static compliance (p = 0.011) and increased pulmonary permeability (p = 0.013). The highest burden of P. aeruginosa was found at pneumonia diagnosis in all animals, as well as a high inflammatory response shown by a release of interleukin (IL)-6 and IL-8. At histological examination, only animals comprising the pneumonia-with-VILI group presented signs consistent with diffuse alveolar damage. Conclusions: In conclusion, we established an accurate pulmonary sepsis-induced ARDS model.</p

A long-lasting porcine model of ARDS caused by pneumonia and ventilator-induced lung injury

Animal models of acute respiratory distress syndrome (ARDS) do not completely resemble human ARDS, struggling translational research. We aimed to characterize a porcine model of ARDS induced by pneumonia-the most common risk factor in humans-and analyze the additional effect of ventilator-induced lung injury (VILI). Bronchoscopy-guided instillation of a multidrug-resistant Pseudomonas aeruginosa strain was performed in ten healthy pigs. In six animals (pneumonia-with-VILI group), pulmonary damage was further increased by VILI applied 3 h before instillation and until ARDS was diagnosed by PaO/FiO < 150 mmHg. Four animals (pneumonia-without-VILI group) were protectively ventilated 3 h before inoculum and thereafter. Gas exchange, respiratory mechanics, hemodynamics, microbiological studies and inflammatory markers were analyzed during the 96-h experiment. During necropsy, lobar samples were also analyzed. All animals from pneumonia-with-VILI group reached Berlin criteria for ARDS diagnosis until the end of experiment. The mean duration under ARDS diagnosis was 46.8 ± 7.7 h; the lowest PaO/FiO was 83 ± 5.45 mmHg. The group of pigs that were not subjected to VILI did not meet ARDS criteria, even when presenting with bilateral pneumonia. Animals developing ARDS presented hemodynamic instability as well as severe hypercapnia despite high-minute ventilation. Unlike the pneumonia-without-VILI group, the ARDS animals presented lower static compliance (p = 0.011) and increased pulmonary permeability (p = 0.013). The highest burden of P. aeruginosa was found at pneumonia diagnosis in all animals, as well as a high inflammatory response shown by a release of interleukin (IL)-6 and IL-8. At histological examination, only animals comprising the pneumonia-with-VILI group presented signs consistent with diffuse alveolar damage. In conclusion, we established an accurate pulmonary sepsis-induced ARDS model. The online version contains supplementary material available at 10.1186/s13054-023-04512-8

A search for very young Planetary Nebulae

Despite numerous efforts, the transition from Asymptotic Giant Branch (AGB) stars to Planetary Nebulae (PN) is a poorly understood phase of stellar evolution. We have therefore carried out interferometric (VLA) radio observations of a sample of hot post-AGB stars, selected on the basis of their optical and infrared properties. Ten sources out of the 16 observed were detected. This indicates that most of our targets are surrounded by a nebula where the ionization has already started. This definitively determines the evolutionary status of the selected sources and provides us with a unique sample of very young Planetary Nebulae (yPNe). A comparison with another sample of yPNe confirms our working hypothesis that our targets are indeed very young, probably just in the transition toward PN. Finding transition objects is extremely important as they can provide unique clues for a better understanding of this important phase of stellar evolution.Comment: 10 pages, 6 figure