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Electrolyte imbalance caused by the undesired vanadium-ions cross-over and water transport through the membrane is one of the main critical issues of vanadium redox flow batteries, leading to battery capacity loss and electrolytes volume variation. In this work, the evolution of discharged capacity and electrolyte volume variation were firstly investigated adopting commercial electrolyte for hundreds of charge-discharge cycles in vanadium redox flow batteries employing different membranes, varying thickness and equivalent weight. Subsequently, with the support of a 1D physics-based model, the origin of the main phenomena regulating capacity decay and volume variation has been identified and different modifications in the preparation of electrolytes have been proposed. Electrolytes characterized by an equal proton concentration between the two tanks at the beginning of cycling operation turned out to limit capacity decay, while increasing electrolyte proton concentration was effective also in the mitigation of volume variation. The most promising electrolyte preparation combined the effect of high proton concentration and null osmotic pressure gradient between the two tanks: compared to commercial electrolyte this preparation reduced the capacity decay from 47.7% to 20.9%, increased the coulombic efficiency from 96.2% to 98.9% and the energy one from 79.9% to 83.4%, and also implied a negligible volume variation during cycles. The effectiveness of this electrolyte preparation has been verified with different membranes, increasing the range of validity of the results, that could be thus applied in a real system regardless of the adopted membrane.

[ES]Se ha elaborado una nueva base de datos de precipitaciones medias mensuales y temperaturas máximas y mínimas medias mensuales, con la que se han analizado los datos de 142 estaciones meteorológicas obtenidos de la Agencia Estatal de Meteorología (AEMET) para el periodo (1989-2018). En este estudio se presentan los resultados de diferentes pruebas de homogeneización y relleno de 134, 172 y 176 series de temperaturas y precipitaciones provenientes de las estaciones ubicadas en la región de Extremadura. Para ello, se realizó un primer control de calidad de los datos cumpliendo con los requisitos de la Organización Meteorológica Mundial (OMM) y las recomendaciones indicadas por el Real Instituto Meteorológico de los Países Bajos (KNMI). Posteriormente se llevó a cabo la homogeneización de las series utilizando el software Climatol, en el que se han implementado diferentes funciones que permiten depurar los datos a través de un análisis de los valores atípicos y de la homogeneidad, así como la completación de las lagunas de las series. Los análisis confirman la obtención de unos niveles de depuración de los datos muy altos, confiables y de buena calidad; obteniendo así una nueva base de datos para posteriores estudios climáticos. [EN]A new database of monthly average rainfall and monthly average maximum and minimum temperatures has been developed, with which data from 142 weather stations obtained from the Agencia Estatal de Meteorología (AEMET) for the period (1989-2018) have been analysed. This study presents the results of different homogenisation and backfilling tests of 134, 172 and 176 temperature and precipitation series from stations located in the region of Extremadura. For this purpose, a first quality control of the data was carried out in compliance with the requirements of the World Meteorological Organisation (WMO) and the recommendations indicated by the Royal Netherlands Meteorological Institute (KNMI). Subsequently, the series were homogenised using Climatol software, in which different functions have been implemented to clean the data through an analysis of outliers and homogeneity, as well as filling in the gaps in the series. The analyses confirm the achievement of very high, reliable and good quality data cleaning levels, thus obtaining a new database for further climate studies. Esta investigación fue financiada por la Junta de Extremadura y el Fondo Europeo de Desarrollo Regional (FEDER) a través de la ayuda al grupo de investigación Alcántara (TIC008), GR21006, y el Proyecto IB18001 “Análisis y modelización del impacto del cambio climático sobre la distribución de zonas vitícolas en Extremadura”. Ponencia presentada en: XII Congreso de la Asociación Española de Climatología celebrado en Santiago de Compostela entre el 19 y el 21 de octubre de 2022.

Recycled waste materials obtained from industrial and agricultural processes are becoming promising thermal and acoustic insulating solutions in building applications; their use can play an important role in the environmental impact reduction. The aim of the present paper is the evaluation of the thermal performance of recycled waste panels consisting of cork scraps, rice husk, coffee chaff, and end-life granulated tires, glued in different weight ratios and pressed. Six panels obtained from the mixing of these waste materials were fabricated and analyzed. In particular, the scope is the selection of the best compromise solutions from the thermal and environmental points of view. To this aim, thermal resistances were measured in laboratory and a Life Cycle Assessment (LCA) analysis was carried out for each panel; a cross-comparative examination was performed in order to optimize their properties and find the best panels solutions to be assembled in the future. Life Cycle Analysis was carried out in terms of primary Embodied Energy and Greenhouse Gas Emissions, considering a ‘‘cradle-to-gate” approach. The obtained thermal conductivities varied in the 0.055 to 0.135 W/mK range, in the same order of magnitude of many traditional systems. The best thermal results were obtained for the panels made of granulated cork, rice husk, and coffee chaff in this order. The rubber granulate showed higher values of the thermal conductivity (about 0.15 W/mK); a very interesting combined solution was the panel composed of cork (60%), rice husk (20%), and coffee chaff (20%), with a thermal conductivity of 0.08 W/mK and a Global Warming Potential of only 2.6 kg CO2eq/m2. Considering the Embodied Energy (CED), the best solution is a panel composed of 56% of cork and 44% of coffee chaff (minimum CED and thermal conductivity).

Flare stacks are a key element in the safety of petrochemical and refinery industries; the correct operating conditions thereof must be ensured through a schedule for the periodic reviewing of all parts thereof. Advances in Non-Destructive Testing (NDT) in recent years and the application thereof to this field allow reliable, objective information to be obtained. This article describes and groups together the main applicable NDT techniques, analysing their advantages and disadvantages, updated with the new possibilities offered by unmanned aircraft or drones.

This work evaluates, for the first time, the possibility of producing multifunctional alkali-activated composites combining ultra-low density, low thermal conductivity, high acoustic absorption, and good moisture buffering capacity. The composites were prepared using cork as a lightweight aggregate. This novel material might promote energy savings and tackle the CO2 emissions of the building sector, while simultaneously improve the comfort for inhabitants (e.g. humidity levels regulation and sound pollution reduction). The composites apparent density (as low as 168 kg/m3) and thermal conductivity (as low as 68 mW/m K) are amongst the lowest ever reported for alkali-activated materials (AAM) composites and foams, while their sound absorption ability is comparable to the best performing AAM foams reported to date, but in addition these eco-friendly composites also show good ability to passively adjust the humidity levels inside buildings. The multifunctional properties shown by the cork – AAM composites set them apart from other conventional building materials and might contribute to the global sustainability of the construction sector. Peer Reviewed

AbstractLightning is the main precursor of natural wildfires and Long-Continuing-Current (LCC) lightning flashes are proposed to be the main igniters of lightning-ignited wildfires (LIW). Previous studies predict a change of the global occurrence rate and spatial pattern of total lightning. Nevertheless, the sensitivity of lightning-ignited wildfire occurrence to climate change is uncertain. Here, we investigate space-based measurements of LCC lightning associated with lightning ignitions and present LCC lightning projections under the Representative Concentration Pathway RCP6.0 for the 2090s by applying a recent LCC lightning parameterization based on the updraft strength in thunderstorms. We find a 41% global increase of the LCC lightning flash rate. Increases are largest in South America, the western coast of North America, Central America, Australia, Southern and Eastern Asia, and Europe, while only regional variations are found in northern polar forests, where fire risk can affect permafrost soil carbon release. These results show that lightning schemes including LCC lightning are needed to project the occurrence of lightning-ignited wildfires under climate change.

Localized energy states such as two-color gap solitons are theoretically and numerically predicted in a periodic structure in the presence of a frequency doubling nonlinearity. These parametric solitons exhibit appealing features as compared to the Kerr case. Novel erects such as merging and all-optical buffering are envisaged.