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New proton exchange membranes based on ionic liquid doped chitosan
No full textABSTRACT: The development of new proton exchange membranes (PEM) for electrochemical devices have attracted researcher's attention in the pursuit for more sustainable and cost-effective technologies for clean energy production and conversion. In this work, new doped chitosan (CS) membranes were prepared by the casting method. Chitosan is an abundant, biodegradable and non-toxic material, and as a membrane, a sustainable and cheaper alternative to those perfluorinated and commonly used, such as Nafion. Three different ionic liquids were employed as dopants, ([EMIM][OTf], [EMIM][FSI] and [MIMH][HSO4]), in various concentrations and up to 50 wt% load. The new membranes were characterized by ATR-FTIR, thermogravimetry, using TGA and DSC techniques to assess their thermal properties, and by SEM, to analyse their surface morphology. Proton conduction properties of the new membranes were assessed by Electrochemical Impedance Spectroscopy (EIS). The new doped membranes showed an increase in the proton conduction compared with pristine chitosan membranes. The incorporation of ionic liquids into chitosan membranes improved their proton conductivity and thermal properties, with [EMIM][OTf] and [MIMH][HSO4] showing the most promising results. A 2-fold increment in the proton conduction was generally observed with the increase of the temperature from 30 to 60 degrees C. The best proton conductivity was found at 60 degrees C for the membrane doped with [EMIM][OTf], with a value of 47 mS.cm(-1)
Geomatemática Aplicada ao Estudo de Contaminações decorrentes de Áreas Mineiras Abandonadas. O caso de estudo da Mina de Vale das Gatas (Portugal)
No full textRESUMO: O objetivo deste trabalho é a aplicação de uma série de modelos geomatemáticos que analisem, não só o sistema de relações entre os diferentes Elementos Potencialmente Tóxicos (EPT), mas também as suas dispersões espaciais nas áreas circunvizinhas a antigas explorações mineiras abandonadas. O recurso a técnicas da estatística multivariada no âmbito dos Métodos Fatoriais (Análise em Componentes Principais e Análise de Correspondências), aliada a modelos geoestatísticos caracterizadores do comportamento espacial dos EPT, permitem não só efetuar um diagnóstico ambiental do local, mas também equacionar uma eventual viabilidade económica para o reaproveitamento (remineração e revalorização) das escombreiras de antigas explorações mineiras abandonadas
Fire-resistant materials: characterization and thermal behavior of intumescent gels for fire resistant glass [Poster]
No full textFramework of Initial Selection of Offshore Energy Island Location for Sustainable Water Desalination [Resumo]
No full textABSTRACT: In this paper, a framework for the selection of an energy island location to supply power for water desalination plants with cleaner and more sustainable energy has been developed. The developed framework aims to evaluate the feasibility of creating offshore energy islands and select its location by considering factors such as renewable energy potential, site suitability, marine traffic, future developments, and proximity to desalination facilities. The energy and water data have been collected from available published data on marine traffic, water desalination production and government reports. Solar power data were obtained from the Ministry of Natural Resources via RETScreen, wave data were sourced from Windguru, and wind power data were obtained from both sources. The data were used for the Inverse Distance Weighting (IDW) interpolation and Multi- Criteria Decision Analysis (MCDA) to develop the framework. The developed framework has been utilized to develop an energy Island in the Red Sea to power the water desalination plants along the KSA west shore. The findings demonstrate the significant potential of energy islands to partly mitigate Carbon Dioxide (CO₂) emissions from desalination plants, advancing global efforts toward water sustainability and supporting long-term goals for achieving net-zero emissions. The study also emphasizes the importance of further research into wave energy in the Red Sea, as the lack of real-time data and comprehensive resources limits accurate assessments.COST Action CA20109 Modenerlands, supported by COST (European Cooperation in Science and Technology
SedDARE-IB: an open-access repository of sediment data for the Iberian Peninsula and its continental margins
No full textABSTRACT: Sediments provide valuable information for geologists and geophysicists whenever they strive to understand, and reproduce, the geological evolution, lithology, rock properties, seismic response, and geohazards of a region. The analysis of sedimentary sequences is thus useful for the interpretation of depositional environments, sea-level change, climate change, and recognition of the sediments' source areas. By integrating sedimentary data into geophysical modeling, such interpretations are improved in terms of their accuracy and reliability. To further help our understanding of the Iberian Peninsula's geological evolution, geological resources, and geohazards, this work presents to the scientific community the SedDARE-IB data repository. This repository includes available data on the depth to the Base of the Cenozoic and Top of the Paleozoic stratigraphic markers for the Iberian Peninsula, the surrounding West Iberian Atlantic Margin and Western Mediterranean Neogene basins, or the acoustic basement as interpreted for the Valencia Trough and Alboran Mediterranean basins. As an example of the broad applicability of the data included in SedDARE-IB, we investigate how sediment thickness affects the depth to the 150 degrees C isotherm in specific basins, as commonly used in geothermal exploration. The calculated trend suggests that, given constant measured surface heat flow and thermal conductivity, the 150 degrees C isotherm becomes shallower as the sediment thickness increases, until a critical threshold value is reached for the latter. The SedDARE-IB database has been compiled thanks to a Portuguese-Spanish collaboration promoting open data exchange among institutions and research groups. SedDARE-IB is freely available at 10.20350/digitalCSIC/16277 (Torne et al., 2024), bringing opportunities to the scientific, industrial, and educational communities for diverse applications
Megaglomerospora lealiae nov. gen., nov. sp. from the upper Carboniferous of Portugal: the largest glomeromycotan fungal spores
No full textABSTRACT: A new genus and species of fossil fungus, Megaglomerospora lealiae, is described from the Bu & ccedil;aco Carboniferous Basin (upper Stephanian C, Upper Pennsylvanian, upper Carboniferous), in central western Portugal. The new fossil fungus consists of a dense cluster of silicified large spores. These new fungal spores are oblong, subelliptical to subspherical-shaped, with a glabrous surface characterized by having a lipid-filled lumen, and display a strong septate-like hypha attached. The presence of lobe-shaped germination shields suggests close affinities to Diversisporales (Glomeromycota). Megaglomerospora lealiae nov. gen., nov. sp. is remarkably distinctive because it is by far the largest fossil fungal spore (similar to 1.6 mm long) documented for the phylum Glomeromycota. This is the first report of an endomycorrhizal-like fungus from the Carboniferous of Iberia. (c) 2025 Elsevier Masson SAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies
Intumescent Gels for Fire-Resistant Glass: Thermal Insulation, UV Protection, and Durability Studies [Poster]
No full textDriving Transformative Change: Assessing the Direction and Design of Decarbonization Policies in the EU, US, China, and Japan
No full textABSTRACT: The transition to low‐carbon economies demands policies that drive both decarbonization and deep socioeconomic transformation. This paper assesses the “transformative potential” of 3,400 decarbonization policies from Europe, the US, China, and Japan. We define transformative potential considering both policy direction – alignment with sustainability goals, and policy design ‐ presence of mechanisms that can induce transformation, such as experimentation, actor diversity, multiscale coordination, and reflexivity. The research shows that when we consider a broad universe of decarbonization policies, transformative potential is still limited: only 20% of policies align with at least one transition pathway and include at least one transformative mechanism; and just 2% include three or more mechanisms. By identifying distinguishing features of these higher transformative potential policies, the paper contributes to understanding how technological, sectoral and contextual factors shape the capacity of policies to enable transformative change
Assessment of Terceira Island (Azores) susceptibility to volcanic hazards
No full textABSTRACT: Terceira Island has three active volcanic systems, including two central volcanoes and a fissure zone. Terceira’s eruptive history over the past 23,000 years has been marked by explosive eruptions of trachytic nature, with extrusion of trachytic lavas, as well as basaltic eruptions of low explosivity and hydromagmatic eruptions. All this diversity demonstrates
that the island is exposed to a wide diversity of volcanic hazards. To assess the susceptibility of the island to these hazards its eruptive history was analyzed and used to produce simulations to determine the areas potentially affected by future eruptions.RESUMO: A ilha Terceira possui três sistemas vulcânicos ativos, incluindo dois vulcões centrais e uma zona fissural. A história eruptiva da Terceira nos últimos 23.000 anos tem sido marcada por erupções explosivas de natureza traquítica, com extrusão de lavas traquíticas, bem como erupções basálticas de baixa explosividade e erupções hidromagmáticas. Toda esta diversidade demonstra que a ilha está exposta a uma multiplicidade de riscos vulcânicos. Para avaliar a suscetibilidade da ilha a estes riscos, a sua história eruptiva foi analisada e utilizada para produzir simulações e determinar as áreas potencialmente afetadas por futuras erupções