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Evaluation of different fractionation methods for the simultaneous protein and carbohydrate extraction from microalgae
No full textABSTRACT: The production of high-value products from microalgae, one of the preferred emerging biorefineries' feedstocks, relies on the crucial step of biomass fractionation. In this work, the fractionation of Chlorella vulgaris and Scenedesmus obliquus biomass was tested for protein extraction using a wide range of physical, chemical, and enzymatic treatment combinations, including ultrasound, cell homogenizer, cellulase, and alcalase combinations in aqueous and alkali extraction conditions. The impact of these processes on biomass carbohydrates was also evaluated. Alkaline-assisted ultrasound treatments using alcalase presented the highest protein extraction yield, reaching 90 g/100 g protein on C. vulgaris, closely followed by the same treatment in aqueous conditions (85 g/100 g protein). The same aqueous treatment achieved the best performance on S. obliquus, reaching 82 g/100 g protein. All treatments on both microalgae partially solubilized the polysaccharide fraction with all alkaline treatments solubilizing over 50 g/100 g sugars for all conditions. Overall, all the treatments applied were effective methods for biomass fractionation, although they showed low selectivity regarding the individual extraction of protein or carbohydrates.info:eu-repo/semantics/publishedVersio
Sustainability Assessment of 2G Bioethanol Production from Residual Lignocellulosic Biomass
Get PDFABSTRACT: The development of sustainable biofuels can help to reduce the reliance on fossil fuels and mitigate the impact of climate change. This study analyzes bioethanol production from agro-forestry residual biomass, namely eucalyptus residues and corn stover. The study includes process simulation using Aspen Plus software, followed by economic analysis and life cycle assessment (LCA) with the help of SimaPro software and by applying the environmental footprint (EF) 3.0 method. The economic analysis on the biorefinery’s economic viability, equipment, and production costs reveals a positive decision for bioethanol production from eucalyptus residues due to logistical and transportation costs. The minimum ethanol selling price (MESP) obtained was 2.19 €/L and 2.45 €/L for eucalyptus residues and corn stover, respectively. From the LCA with a functional unit of 1 MJ of ethanol, bioethanol production from eucalyptus residues results in a single score impact of 37.86 µPt, whereas for corn stover, it is 33.47 µPt. In the climate change impact category, the eucalyptus residues scenario has an impact of 0.264 kg CO2 eq/MJ ethanol while corn stover leads to 0.254 kg CO2 eq/MJ ethanol. In-situ enzyme production, heat integration, and the use of renewable energy sources were also analyzed. Combining in situ enzyme production with renewable energy sources lowers CO2 equivalent emissions by 89% for both feedstocks, in comparison to the base-case scenario.info:eu-repo/semantics/publishedVersio
Idade e ambientes deposicionais da sucessão do Karoo Inferior da Bacia Carbonífera de Moatize em Moçambique: compreenções sobre a história pós-glacial do Gondwana central
No full textN/
Bioprocess to produce biostimulants/biofertilizers based on microalgae grown using piggery wastewater as nutrient source
No full textABSTRACT: In the present work, two downstream processes - high-pressure homogenization at 100 (HPH-100) and 1200 bar (HPH-1200), and enzymatic hydrolysis (EH) - were tested to produce biostimulant extracts from Tetradesmus obliquus grown in piggery wastewater at two concentrations (12.8 and 88.3 g/L). Extracts before and after centrifugation (C) were evaluated in four bioassays using garden cress (germination), mung bean (auxin-like activity), and cucumber (auxin- and cytokinin-like activity) relative to distilled water. The initial microalgal culture, without any treatment, had the best germination results (162 % at 0.2 g/L) and the only one that showed cytokinin-like activity (141 % at 0.5 g/L). In both auxin-like bioassays, the HPH-1200 + C and EH + C originated high values (186 and 155 % for cucumber, 290 and 285 % for mung bean, respectively). For mung bean, the HPH-1200 achieved the highest auxin-like effect (378 %). Finally, the extracted biomass contained essential nutrients for biofertilization, complementing the biostimulant extracts for sustainable agriculture application.info:eu-repo/semantics/publishedVersio
Performance assessment of current and new market designs and trading mechanisms for Local Energy Communities (Case Study A) : Deliverable D5.2
No full textProject TradeRES - New Markets Design & Models for 100% Renewable Power SystemsN/
Mapping less sensitive areas with a view to the potential installation of solar and wind electricity generation units [Comunicação oral]
No full textThe Metallogenetic Map of Southern Angola at 1:1.000.000 scale, a preliminary approach
No full textRESUMEN: La República de Angola dispone de un amplio e interesante catálogo de mineralizaciones, según
sus diversos entornos geológicos y geotectónicos, que cubren edades desde el arcaico superior hasta épocas
más recientes. Esto hace de Angola una región de gran interés por su potencial en yacimientos minerales.
Prueba de ello es el fruto de la exploración e importante actividad minera desarrollada a lo largo de las
últimas décadas, que ha permitido el descubrimiento de importantes yacimientos de elementos de interés
económico (p.ej., Fe, Au, Li, ETR, diamantes, etc.), algunos de los cuales se encuentran actualmente
activos, abriendo nuevas expectativas mineras en la región. El presente Mapa Metalogenético del Sur de
Angola a escala 1:1.000.000 fue elaborado como parte del programa de Cartografía Geológica del Plan
Nacional de Geología de Angola (PLANAGEO, 2014-2022). Este mapa reagrupa y destaca la distribución
de las concentraciones minerales, definiendo por primera vez las provincias metalogenéticas del sur de
Angola, que son función directa de la relación entre la mineralización y las características geológicas de la
región, y servirá de base para futuras investigaciones de exploración minera.ABSTRACT: The Republic of Angola has a very diverse and interesting catalogue of mineralisations,
determined by their geological and/or geotectonic environments, spanning from the upper Archaean to
more recent times. This makes Angola significant for potential mineral deposits. The exploration and
mining activities over recent decades have led to the discovery of economically valuable deposits of various
elements, such as Fe, Au, Li, REE, and diamonds, some of which are currently active. As a result, new
mining opportunities have been created in the region. The Metallogenetic Map of Southern Angola at
1:1.000.000 scale was part of the Geological Mapping programme of the National Geology Plan of Angola
(PLANAGEO, 2014-2022). This map highlights the distribution of mineral concentrations and defines for
the first time the metallogenic provinces of southern Angola, that are directly linked to the geological
features of the region. This information will serve as a basis for future mineral exploration research.N/
Design for Sustainability Tools: Definition and criteria towards practical use
No full textABSTRACT: The evolution of design to meet the growing sustainability challenges has led to the development of knowledge expressed in different approaches, principles and strategies. To be able to operationalize this knowledge, several design for sustainability (DfS) tools have been created. However, these tools have not been the target of massive and systematic practical use by designers, nor have they been the subject of many studies that allow analyzing, classifying and understanding their capabilities in a real context to improve application rates. With the end goal of supporting designers in using DfS tools more systematically, this research work aims to establish two essential foundations that can lay the ground for the practical selection and application of tools in the future: 1) a clear and comprehensive definition of what constitutes a DfS tool from the designer's perspective, including its scope and boundaries; 2) a list, hierarchization, and evaluation of criteria for classifying, organizing, and selecting tools based on project and designer needs. The methodology used in this research incorporates three main methods: 1) literature review to establish the state-of-the-art, basis for constructing a definition of DfS tool and for identifying and selecting criteria; 2) survey for designers to validate the main components of the DfS tool definition; 3) value analysis methodology for classifying and valuing the classification criteria by designers. Based on this process, it was possible to construct a comprehensive definition of what a DfS tool is and to establish and organize a set of criteria that can facilitate the classification and organization of tools. This allows for better identification of their characteristics, demands and functionalities to align the tools with the design process and its needs.info:eu-repo/semantics/publishedVersio
A new species of Acitheca (Psaroniaceae, Marattiales) with exceptionally and three-dimensionally preserved sporangia from the Buçaco Carboniferous Basin, western central Portugal
No full textABSTRACT: A new fern fossil-species Acitheca machadoi sp. nov. is erected under the family Psaroniaceae (Marattiales), based on adpression fossil remains of fertile foliage from the Monsarros Formation (upper Stephanian C, upper Gzhelian) of the Buçaco Carboniferous Basin, in western central Portugal. Acitheca machadoi comprises relatively narrow and long fertile pinnules bearing exceptionally and three-dimensionally preserved sporangia with in situ spores. These sporangia are elongate (fusiform) and one of the smallest documented for the genus, with a triangular pyramid-like shape in the upper part and rounded to hexagonal-like attachment base. Its occurrence within an assemblage dominated by mesophytes to hygrophytes, with fewer drought-tolerant forms, suggests a wetland environment with a seasonal climate, framed in the transition from humid to dry conditions in western Iberia during the Late Pennsylvanian–early Permian. This palaeobotanical finding provides new insights on the palaeoecology and species diversity of Acitheca, whose currently known fossil record is certainly underestimated.info:eu-repo/semantics/publishedVersio
Transição energética, recursos naturais endógenos e trajetória de desenvolvimento económico: o caso da energia eólica offshore
No full textRESUMO: As alterações climáticas aceleraram o processo de descarbonização. Esta busca pela produção de energias verdes fez (re)emergir o investimento em I&D de novas gerações de tecnologias e em novos locais de exploração. A energia eólica é um destes casos. Por um lado, em Portugal este recurso abunda, com potencial de expansão para o offshore (Bento & Fontes, 2015). Ao mesmo tempo, o país está muito dependente da importação de combustíveis fósseis, pelo que esta é uma questão de aproveitamento dos recursos endógenos e de soberania nacional. Por outro lado, a produção da energia eólica gera desenvolvimento económico. A eólica onshore possibilitou a criação duma trajetória de desenvolvimento industrial. A exploração da energia eólica offshore pode introduzir perturbações nessa trajetória estabelecida. A literatura descreve uma série de pré-condições estruturais regionais para o desenvolvimento da nova trajetória: recursos naturais; conhecimento científico e tecnológico e ativos industriais, infraestruturais e institucionais.info:eu-repo/semantics/publishedVersio