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Rain erosion on the leading edge of wind turbine blades is an intricate engineering challenge for the wind industry. Based on an energetic approach, this work proposes a methodology to characterise the erosion capacity of the raindrop impacts onto the leading edge blades. This methodology can be used with meteorological data from public institutions or from direct measurements at the wind turbine locations. The erosion characterisation is analysed using accumulative and per impact erosive variables, that is, total kinetic energy and kinetic energy per impact. To consider the frequency of impacts, two erosive variables are proposed, namely, total kinetic power and kinetic power per impact. These variables are calculated using the data from the Royal Netherlands Meteorological Institute (Koninklijk Nederlands Meteorologisch Instituut, KNMI) of the last 25 years jointly with the operation specifications of an actual wind turbine model (Suzlon S111). The main contribution to the erosive variables was found to be the wind speed because it controls the rotational velocity of the wind turbine. Also, the intensity of the rainfall and the frequency of meteorological data logging, that is, the temporal resolution of data, play a significant role.

Paweł Łukasz Zajdel, David G. Madden, Robin Babu, Marco Tortora, Diego Mirani, Nikolay Nikolaevich Tsyrin, Luis Bartolomé, Eder Amayuelas, David Fairen-Jimenez, Alexander Rowland Lowe, Mirosław Adam Chorążewski, Juscelino B. Leao, Craig M. Brown, Markus Bleuel, Victor Stoudenets, Carlo Massimo Casciola, María Echeverría, Francisco Bonilla, Giulia Grancini, Simone Meloni, Yaroslav Grosu, Controlling the pressure at which liquids intrude (wet) and extrude (dry) a nanopore is of paramount importance for a broad range of applications, such as energy conversion, catalysis, chromatography, separation, ionic channels, and many more. To tune these characteristics, one typically acts on the chemical nature of the system or pore size. In this work, we propose an alternative route for controlling both intrusion and extrusion pressures via proper arrangement of the grains of the nanoporous material. To prove the concept, dynamic intrusion–extrusion cycles for powdered and monolithic ZIF-8 metal–organic framework were conducted by means of water porosimetry and in operando neutron scattering. We report a drastic increase in intrusion–extrusion dynamic hysteresis when going from a fine powder to a dense monolith configuration, transforming an intermediate performance of the ZIF-8 + water system (poor molecular spring) into a desirable shock-absorber with more than 1 order of magnitude enhancement of dissipated energy per cycle. The obtained results are supported by MD simulations and pave the way for an alternative methodology of tuning intrusion–extrusion pressure using a macroscopic arrangement of nanoporous material.

In the present work, an optimization and validation of an analytical method for the determination of two plasticizer metabolites, 2-ethylhexanol and 4-heptanone in urine, were carried out by multiple headspace solid-phase microextraction (MHS-SPME) coupled to GC-MS. The validation study was successfully performed in terms of stability, method selectivity, linearity, accuracy, recovery, intermediate precision, repeatability, limit of detection (LOD) and limit of quantification (LOQ) in urine samples. Finally, two population group studies were developed in urine samples of volunteers with plastic exposure. First group represents the common plastic exposure of general population and the second one was carried out with healthy moderately trained individuals who have received blood transfusion. This study demonstrates that significantly increased levels of 2-ethylhexanol were found (p < 0.05) in urine samples of volunteers in the early hours after receiving blood transfusion. This work was funded by University of the Basque Country (UPV/EHU) (project GIU19/068) . I. San Román was funded by the University of Basque Country (UPV/EHU) .

RESUMEN Introducción: El hipercortisolismo endógeno provoca cambios en diferentes áreas de la vida en el sentido percibido de bienestar, lo que afecta la calidad de vida; esta debe tenerse en cuenta en la atención integral al paciente. Objetivos: Describir la calidad de vida percibida en los pacientes con hipercortisolismo endógeno e identificar si existe relación entre calidad de vida y algunas características clínicas y hormonales. Métodos: Estudio transversal, 60 pacientes: grupo I (con hipercortisolismo endógeno operados con menos de cinco años) y grupo II (personas con sospecha clínica de hipercortisolismo endógeno), edad entre 20 y 60 años. Se aplicaron cuestionarios de calidad de vida relacionados con el hipercortisolismo endógeno: CushingQoL y Tuebingen CD-25 y planilla de recolección de datos generales, clínicos y hormonales. Se determinó mediana (variables cuantitativas) y frecuencia en las cualitativas. La asociación del puntaje de los cuestionarios y variables cuantitativas, mediante el coeficiente de correlación de Spearman. Se compararon los valores promedio del puntaje entre categorías de las variables cualitativas (clínicas y hormonales categorizadas), mediante la prueba U-Mann Whitney; se consideró diferencia estadística significativa con p ≤ 0,05. Resultados: La mediana del puntaje de los dominios psicoemocional, sexualidad, área social, área corporal, y la suma de todos los dominios fueron mayores en el grupo I. La sexualidad (4,5), el área corporal (6,0) y la suma de todos los dominios (36,5) del I vs. 1,0, 4,0 y 28,0 respectivamente (grupo II), del Tuebingen CD-25 mostraron diferencias estadísticamente significativas, demostrando peor calidad de vida en el grupo I. Con el CushingQoL la mediana del puntaje del grupo I fue menor que la del II (54,1 vs. 74,0), con diferencias estadísticamente significativas (p = 0,00), lo que evidencia peor calidad de vida para el grupo I. Conclusiones: El hipercortisolismo endógeno incide negativamente en la calidad de vida percibida en el grupo de pacientes operados, especialmente en las áreas social, corporal, cognitiva, sexual, y de la conducta alimentaria.

With renewables as the main candidate for future energy sources, efficient energy storage is considered a key to unlock its full potential. In this context, thermal energy storage (TES), particularly molten salt-based TES, is considered as an efficient, simple and a low-cost option. One of the main drawbacks for this technology is the corrosion of vessels storing the salt at elevated temperatures. Recently, the addition of nanoparticles has been reported to be able to mitigate the corrosivity of molten salts by several independent groups. However, no convincing explanation has been established so far as to why such behaviour takes place. In this work, we attempt to give a new insight into anticorrosion performance of molten salts dopped with nanoparticles (molten salts nanofluids) both experimentally and through Molecular Dynamic simulations. XPS-depth profiling, SEM-EDX and XRD experiments together with macroscopic and atomistic modelling were used in this work and the results suggest that the diffusion of nanoparticles into construction materials at high temperatures is one of the corrosion mitigation mechanisms of molten salts nanofluids. This new finding allows the explanation of some of the reported corrosion results and hence paves the way for a new anticorrosion strategy for molten salts and other high-temperature applications.

The mechanical behaviour of zinc dialkyldithiophosphate (ZDDP) tribofilms on diamond-like carbon (DLC) coatings has been studied by combining the nano-indentation experimental data and finite-element modelling. Different constitutive models, whose analysis was performed using a global algorithm that consists of forward and inverse algorithms, were chosen to establish which of them more accurately predicts the actual mechanical behaviour of the ZDDP tribofilms. A non-homogeneous, dual structure, which was also verified by the local stiffness using the AFM force-modulation mode, was found. Based on the proposed algorithm, the mechanical properties of the ZDDP tribofilms were found, e.g. the elastic modulus E=26 GPa and the yield stress Y=1.55 GPa for the harder component and approximately E=1.65 GPa and Y=0.144 GPa for the softer component.

Developments in the wind industry reveal intricate engineering challenges, one of them being the erosion on the leading edge of the wind turbine blades. In this review work, the main issues for the wind industry in the experimentation with respect to erosion are examined. After a historical and general overview of erosion, this review focuses on the rain erosion on the leading edge of the wind turbine blades giving prominence to (1) the rain simulations, (2) experimental erosion facilities, and (3) variables to characterise erosion. These three factors have to be improved to establish a research field enabling the prediction of erosion behaviour and providing useful information about how the rainfall affects the leading edge of the wind turbine blades. Moreover, these improvements in the experimentation of the erosion would be a first step to understand and predict the erosion damage of the wind turbine blades. Finally, this review work also will help to cope with experimental investigations and results in the rain erosion on the leading edge with a deeper critical thinking for future researchers.

Este libro trata de un excepcional caso �si bien no unico� de la presencia femenina en la industria siderurgica durante el Antiguo Regimen. Resume historia de estas factorias, aborda la descripcion del proceso productivo en el que estuvieron inmersas, incluyendo la obtencion y tratamiento de las materias primas, la fundicion en sentido estricto y los productos fabricados. La segunda parte trata de la mano de obra en su conjunto: dimensiones y estructura de la plantilla, modalidades de relacion laboral, salarios y prestaciones, regimen de funcionamiento y los asuntos etnicos relativos al grupo de trabajadores descendientes de flamencos. Se finaliza tratando especificamente a las trabajadoras, las fuentes empleadas para su conocimiento, los aspectos cuantitativos de su presencia, las condiciones de los trabajos que desempenaban y echando una ojeada a la situacion de la mujer en otras factorias analogas de la epoca. Se complementa la obra con fotos, planos, dibujos, tablas, graficos y anejos descriptivos y documentales.

Thermoplastic polyurethane elastomers under cyclic loading–unloading conditions exhibit inelastic effects, mainly stress softening, hysteresis loss and residual strain. In order to discuss the sensitivity of these effects to deformation state (uniaxial tension and pure shear) and to work conditions (maximum strain, strain-rate and stretching direction), this study is concerned with inelastic effects of an extruded thermoplastic polyurethane elastomer when is subjected to loading–unloading cycles. Based on the behaviour of inelastic effects under both tensile conditions, the present work shows that stress softening and residual strain are sensitive to deformation state only when the maximum strain reached causes permanent set. Furthermore, the hysteresis loss shows an independent behaviour depending on maximum strain. Finally, the behaviour of the hysteresis loss and the residual strain is isotropic for the extruded thermoplastic polyurethane elastomer.

Thermoplastic polyurethane elastomers (TPUs) are a kind of elastomer that can be processed as thermoplastics. These elastomers exhibit a highly nonlinear behavior characterized by hyper-elastic deformability. Furthermore, the mechanical behavior of these elastomers is time-dependent, that is, they exhibit a viscoelastic behavior. We describe the material response of a TPU under moderate strains (ɛ < 1) by using an overlay visco-hyperelastic model assuming separation of time dependence from nonlinear stress–strain behavior. To achieve this goal, cyclic loading–unloading experimental tests are carried out for two homogeneous deformation states, uniaxial tension and pure shear, and the strain–stress data are then analyzed to fit a hyperelastic model. Conversely, a viscoelastic model is obtained from relaxation tests. Finally, the visco-hyperelastic model is implemented in a finite element calculation tool (ABAQUS), and the numerical results show a reasonable correlation with experimental data. As a result, a overlay visco-hyperelastic model depending on maximum strain is proposed.

The evolution of the mechanical behaviour of zinc dialkyldithiophosphate (ZDDP) tribofilms on diamond-like carbon coatings during sliding contact has been studied by combining nano-indentation experimental data and finite element modelling. The nano-indentation data from the ZDDP tribofilms were obtained for two different sliding distances of the tribological tests after 15,000 and 216,000 cycles, which correspond to 25 min and 6 h, respectively. A non-homogeneous structure was found for the ZDDP tribofilms after both sliding distances, which were also verified by the local stiffness using the AFM force modulation mode. A dual structure is observed for the ZDDP tribofilms after 15,000 cycles, while three distinct components with different mechanical behaviours were found after 216,000 cycles. It was also found that the mechanical behaviour of the harder component of the ZDDP tribofilms remains almost unchanged for both sliding times, while the softer component tends to stiffen slightly over the sliding time. In addition, using the proposed algorithm with finite element simulations, the mechanical properties of the different components have been obtained, e.g. the elastic modulus E = 25.5 GPa and the yield stress Y = 1.585 GPa of the harder component for both sliding times. The softer component exhibits E = 1.65 GPa and Y = 0.144 GPa after 15,000 cycles and E = 3.5 GPa and Y = 0.17 GPa after 216,000 cycles. Finally, an intermediate component with E = 11.7 GPa and Y = 0.94 GPa has been only found at 216,000 cycles.

El color de los calices de la jamaica (Hibiscus sabdariffa L.) es un criterio de calidad considerado por el consumidor y se relaciona con la concentracion de ciertos fitoquimicos. No se tiene informacion sobre la relacion de este parametro con las caracteristicas fisicoquimicas de los extractos acuosos en variedades de Hibiscus cultivadas en Mexico, por lo que el objetivo del presente trabajo fue determinar el color de calices de ocho variedades de jamaica y establecer su relacion con algunas variables quimicas de los extractos acuosos obtenidos. Para ello se midio el color de los calices (enteros y molidos) y el de los extractos con ayuda de un colorimetro Hunter–Lab. En los extractos se determino el contenido de antocianinas totales (ANT), acido ascorbico (AA), acidez titulable (AT), pH y °Brix. Se encontro que el color de los calices y de los extractos influyo en el contenido de antocianinas y acido ascorbico. Las variedades de calices oscuros presentaron entre cinco y siete veces mas antocianinas que las de calices claros, mientras que la variedad de calices blancos tuvo el mayor contenido de acido ascorbico. De los parametros de color, la luminosidad de los calices molidos puede usarse como estimador del contenido de antocianinas totales, por la elevada correlacion negativa entre estas variables

Mussels are used as bioindicators of chemical pollution in coastal and estuarine waters. We measured the concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phthalate esters (PEs), butyltins, and metals (Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, V, and Zn) in mussel tissues collected from the lower Bilbao estuary (Arriluze, north of Spain) every 2 months from November 2002 to March 2004. The concentration (microg g(-1) dry weight) of PAHs, PCBs, and PEs ranged from 5.1 to 18.3, from 0.04 to 0.2, and from 1.5 to 27.6, respectively. Temporal pattern variations, including maximum and minimum values, were determined for metals and BTs from their concentration profiles during a period of 1 year. The main feature of organic microcontaminants was relatively high concentration values, reflecting the overall industrial and harbour activities of the site. Moreover, the ratios of methylated species and certain other diagnostic ratios suggested a petrogenic origin for PAHs. Finally, the relations among the concentrations found in mussel tissues and the levels of several cell biomarkers were established by a partial least squares model.