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Proteolytic Bacillus sp. Isolation and Identification from Tannery Alkaline Baths
No full textABSTRACT: The application of microbial alkaline proteases holds significant potential for eco-sustainable industrial processes by reducing chemical usage and lowering the costs of effluent treatment. In the search for novel proteases with industrial relevance, several microbial strains were isolated from alkaline baths of the Portuguese tannery agroindustry. The most promising protease-producing strains were selected for identification and further study. Two isolates demonstrated the highest proteolytic activity, reaching 0.51 +/- 0.01 U mL-1 and 0.70 +/- 0.01 U mL-1 after 7.5 h of submerged cultivation in nutrient broth. Based on API biochemical tests, molecular biology techniques, and GC-FAME analysis of membrane lipids, the isolates were identified as Bacillus subtilis and incorporated into INIAV's collection of industrial microbial cultures as B. subtilis CCMI 1253 (BMR2) and B. subtilis CCMI 1254 (BMR1). The most promising protease producer, B. subtilis CCMI 1253 (BMR2), exhibited a maximum specific growth rate of 0.88 +/- 0.10 h-1. The proteases produced exhibited good extracellular proteolytic activity, with adaptability to industrial conditions, indicating their suitability for agroindustry applications such as leather making, detergent formulations and the treatment of effluents and protein residues. The results support the potential of microbial proteases as valuable tools in the bioeconomy and green chemistry
Experimental investigation of a novel wave energy floating platform for hybrid wind-wave applications: The OctaPlat
No full textABSTRACT: The work presents the process of model design and testing and the experimental results for the OctaPlat, a new wave energy floating platform, conceived at IST/ULisboa. A physical model was designed on the basis of the Octaplat concept, which comprises five oscillating water columns (OWCs). The physical model design considered only three of the five OWCs due to infrastructure constraints and was made of acrylic material on a scale of 1:100th scale. The experimental campaign comprised free decay tests and tests under both regular and irregular wave conditions. Different power take-off systems for OWCs (impulse air turbines) were approximated through small orifices. Parameters such as RAO, dimensionless pressure, and the capture width ratio (CWR) were determined and analysed to understand the model performance under different conditions. Under regular waves, the results showed that the coupled hydrodynamic interaction between pitch and surge motions mainly affects the chambers located at the outer edges of the platform. Furthermore, the RAOs of the OWCs seem to be influenced by the natural coupled heave frequency, the natural frequencies of OWC1 and OWC3, and possibly the submultiple of the coupled heave natural frequency (k=1.5). Results also show that the different orifice plates considerably affect the CWR and the peaks' frequencies of its maximum values. Under irregular waves considering full-scale values, for a 2.5 m significant wave height, the peak pneumatic power reached 1.6 MW at 0.077 Hz with an equivalent rotor air turbine diameter of 6.3 m (that is, 30 mm orifice diameter) and 1.9 MW at 0.083 Hz with an equivalent rotor air turbine diameter of approximately 4 m (i.e., 20 mm orifice diameter). For a significant wave height of 3.4 m, the 30 mm orifice produced 3.6 MW at 0.077 Hz, while the 20 mm orifice reached 3.8 MW at 0.091 Hz. These results confirm the platform's feasibility for megawatt-scale wave energy conversion, supporting a key claim of this technology. The experimental results were compared with the numerical ones in terms of CWR. Good agreement was found between both, with a coefficient of determination (R^2) of about 0.94, and the relative difference between them was always less than 20%, except for a few peak deviations
Mineralogical and Geochemical Characterization of Geological Materials
No full textABSTRACT: The following Special Issue compiles original research on the mineralogical, geochemical, and microstructural characterisation of natural and anthropogenic materials. Topics span the weathering and long-term durability of sedimentary rocks, copper mineralisation processes, and archaeometric provenance studies to advanced analytical methods for mortar characterisation, heavy mineral analysis, and polymetallic ore exploration. Contributions highlight innovations in neutron imaging, SEM-based fast elemental mapping, quantitative XRD, and adsorption studies on clay minerals. Emphasis is placed on the scientific understanding of mineral transformations, the sustainable use of geological resources, heritage conservation, and the recycling potential of mining waste. By combining traditional petrography with emerging machine learning and supervised classification approaches, the papers demonstrate how mineralogical research is becoming increasingly interdisciplinary, supporting geology, archaeology, environmental sciences, and resource management. This reprint provides a valuable reference for researchers across Earth and material sciences
Questioning in 7th grade Natural Sciences textbooks: From Curricular Goals to Essential Learning
No full textRESUMO: O manual escolar é um recurso didático muito utilizado em contexto escolar. Deste modo, a qualidade deste recurso é crucial devendo ser elaborado de forma correta, completa e diversificada. O objetivo deste estudo é avaliar o questionamento do subtema “Estrutura e dinâmica interna da Terra” presente nos manuais do 7.º ano de escolaridade da disciplina de Ciências Naturais. Para esta análise, utilizaram-se três livros recentes e as correspondentes versões anteriores. Com este estudo foi possível concluir que houve uma redução do número global de questões nos manuais novos. Também foi possível verificar que as questões são maioritariamente enciclopédicas (questões de baixo nível cognitivo) e que apenas foram encontradas algumas questões interdisciplinares. Relativamente às questões de avaliação de diagnóstico, estas são pontuais ou mesmo inexistentes. Os resultados obtidos, com a avaliação desta subunidade, não se coadunam com as orientações curriculares exaradas pelo Ministério da Educação.ABSTRACT: Textbooks are a didactical resource widely used in school context. As so, the quality of such resources is crucial as they should be prepared in a correct, complete and diversified way. The aim of this study is to evaluate the questions of the sub-theme “Structure and internal dynamics of the Earth” presented in the 7th grade Natural Sciences textbooks. For this analysis, three recent books and their previous versions were used. With this study it was possible to conclude that there was a reduction in the overall number of questions in the new textbooks. It was also possible to verify that the majority of the questions were encyclopaedic (questions of low cognitive level) and that only few interdisciplinary questions were found. Regarding diganostic assessment questions, these are occasional or even non-existent. The results obtained with the evaluation of the subtheme are not consistent with the curricular guidelines issued by the Ministry of Education
Mapping of the Buçaco : Penedos de Góis syncline
No full textRESUMO: A uma escala normal de trabalho de campo (1/25000), surgem problemas na representação cartográfica de algumas das unidades definidas no sinclinal de Buçaco-Penedos de Góis, que têm espessuras de 50 metros, ou menos. Foi necessário agrupá-las. Isto conduz-nos a uma sequência litostratigráfica apresentada neste trabalho para a maior parte das separações cartográficas já efetuadas por Delgado (1908), embora com as designações criadas por autores posteriores.ABSTRACT: At a normal fieldwork scale (1/25000) problems arise in the cartographic representation of some of the units defined in the Buçaco-Penedos de Góis syncline, which have thicknesses of 50 meters or less. It was necessary to group them resulting in a lithostratigraphic sequence for most of the cartographic separations already carried out by Delgado (1908), although with the designations created by later authors
Strawberry Tree Fruit Residue as Carbon Source Towards Sustainable Fuel Biodesulfurization by Gordonia alkanivorans Strain 1B
No full textABSTRACT: Biodesulfurization (BDS) is a clean technology that uses microorganisms to efficiently remove sulfur from recalcitrant organosulfur compounds present in fuels (fossil fuels or new-generation fuels resulting from pyrolysis and hydrothermal liquefaction). One of the limitations of this technology is the low desulfurization rates. These result in the need for greater amounts of biocatalyst and lead to increased production costs. To mitigate this issue, several approaches have been pursued, such as the use of alternative carbon sources (C-sources) from agro-industrial waste streams or the co-production of high-added-value products by microorganisms. The main goal of this work is to assess the potential of strawberry tree fruit residue (STFr) as an alternative C-source for a BDS biorefinery using Gordonia alkanivorans strain 1B, a well-known desulfurizing bacterium with high biotechnological potential. Hence, the first step was to produce sugar-rich liquor from the STFr and employ it in shake-flask assays to evaluate the influence of different pretreatments (treatments with 1-4% activated charcoal for prior phenolics removal) on metabolic parameters and BDS rates. Afterwards, the liquor was used as the C-source in chemostat assays, compared to commercial sugars, to develop and optimize the use of STFr-liquor as a viable C-source towards cost-effective biocatalyst production. Moreover, the high-market-value bioproducts simultaneously produced during microbial growth were also evaluated. In this context, the best results, considering both the production of biocatalysts with BDS activity and simultaneous bioproduct production (carotenoids and gordofactin biosurfactant/bioemulsifier) were achieved when strain 1B was cultivated in a chemostat with untreated STFr-liquor (5.4 g/L fructose + glucose, 6:4 ratio) as the C-source and in a sulfur-free mineral-minimized culture medium at a dilution rate of 0.04 h-1. Cells from this steady-state culture (STFr L1) achieved the highest desulfurization with 250 mM of dibenzothiophene as a reference organosulfur compound, producing a maximum of approximate to 213 mM of 2-hydroxibyphenil (2-HBP) with a corresponding specific rate (q2-HBP) of 6.50 mu mol/g(DCW)/h (where DCW = dry cell weight). This demonstrates the potential of STFr as a sustainable alternative C-source for the production of cost-effective biocatalysts without compromising BDS ability. Additionally, cells grown in STFr L1 also presented the highest production of added-value products (338 +/- 15 mu g/g(DCW) of carotenoids and 8 U/mL of gordofactin). These results open prospects for a future G. alkanivorans strain 1B biorefinery that integrates BDS, waste valorization, and the production of added-value products, contributing to the global economic viability of a BDS process and making BDS scale-up a reality in the near future
Contribution to the Development of a New Value Chain in the Marine Renewable Energy Sector [Resumo]
No full textABSTRACT: As part of the commitments made in the NECP2030 for Portugal, an increase in wind capacity is planned, including an additional 10.4 GW onshore and 2 GW offshore. In this sense, it is necessary to assess the conditions for the creation of a new industrial value chain that will accelerate this development and offer attractive conditions for the involvement of the industrial sector, providing conditions for the objectives recommended in the NECP 2030 to be met. Projects OffshorePlan - Planning for the Use of Offshore Renewable Energies in Portugal, and OceanTrans - Ocean energy technologies transformative potential analyzed the relevant socio-economic component for this sector, namely the process of creating a new industrial value chain to support the development of marine renewable energies. As part of this research, a questionnaire survey was conducted targeting companies in sectors with complementary skills and resources, directly or indirectly related to the development of projects in this area. The questionnaire yielded 114 responses from companies already active and 182 from companies willing to become involved in the future. The results allowed us to obtain a global view of the actual and potential involvement of the industrial sector, as well as to gain some insight into how companies view the requirements to operate in this area and the main barriers to their performance. This article presents the main findings obtained in the scope of this research and discusses their contribution to the advancement of the marine renewable energy sector and, as such, to the development of offshore wind energy in Portugal.COST Action CA20109 Modenerlands, supported by COST (European Cooperation in Science and Technology
Deep geothermal resources in the Pan-European Atlas of Sustainable GeoEnergy Capacities (GSEU project): The Play-based Exploration Pyramid concept
No full textABSTRACT: This work introduces version 1.0 of the Pan-EU Atlas of Sustainable GeoEnergy Capacities (SGC), delivered by the GSEU (Geological Service for Europe) project. It details the methodology evolving from the Play-Based Exploration Pyramid (PBEP) concept into a practical approach for sharing harmonized knowledge about deep geothermal energy potential across Europe. This Atlas aims to deliver a standardized and generalized understanding of geothermal resources, emphasizing the potential in the framework of the Europe’s sustainable energy transition. The PBEP concept of the PanEU Atlas of SGC follows a multiscale geothermal exploration approach that systematically narrows focus from a geosystem to local scale, organizing technical and scientific data from broad, low-knowledge areas to highly detailed high-knowledge regions or local targets. It aims to ensure a refined understanding of geothermal plays, improving the identification of potential areas across Europe, spanning four levels (Level 0 to Level 3) and incorporating further refined knowledge in the assessment of geothermal resource. Levels 0 and 1 GIS datasets were published along spring 2025 in the European Geological Data Infrastructure (EGDI) as version 1.0 of the Atlas. Information available includes public data from boreholes and thermal springs (Level 0), which forms the basis for Level 1 - a harmonized map highlighting favourable prospecting areas for deep-origin geothermal resources, classified according to Geothermal Play Types (GPTs). This is accompanied by a catalogue of factsheets for each delineated GPTs across EU (~ 400 in total), summarizing the generalized findings along with a report on description and metadata. This scale-dependent process will continue in version 2 of the Atlas, with Level 2 focusing on identified potential geothermal reservoirs using 1D lumped stochastic estimations for geothermal resources and medium to high heat storage potential into deep aquifers. Finally, Level 3 will provide detailed local-scale evaluations of specific targets, compiling already existing maps and models containing spatial-distributed reservoir assessed information in 2D and/or 3D
Shining a light on outdoor algal systems for wastewater treatment: How artificial light enhancement impacts biomass costs and life cycle
No full textABSTRACT: Microalgae-based wastewater treatment is increasingly viewed as a cleaner production strategy, combining nutrient removal and biomass generation for high-value applications. However, productivity constraints remain a critical barrier to broader implementation. This study examines the viability of integrating light-emitting diodes (LEDs) into outdoor bubble column reactors for domestic wastewater treatment and biomass production, focusing on environmental impacts and techno-economic performance. Three lighting regimes—natural light only (control), 12-h LED cycles, and 24-h LED cycles—were experimentally evaluated and scaled up using Aspen Plus® simulation. Life cycle assessments (LCA) were conducted to quantify environmental impacts (ReCiPe, 2016 method), and a detailed techno-economic analysis determined minimum biomass selling prices. Compared to the control, LED-assisted systems increased biomass yields by 24–34 %, yet capital and operational costs offset productivity gains. Under grid electricity, minimum selling prices considering capital and operational costs ranged from 80.76 to 91.37 USD/kg for LED systems versus 68.85 USD/kg for the control. Photovoltaic (PV) integration reduced operational costs by up to 16.89 %, but LED scenarios remained more expensive. LCA findings highlighted substantially higher environmental impacts (78–149 times) for LED systems, partly alleviated by PV-powered operations. Sensitivity analysis identified nutrient availability, process scale, and reactor costs as pivotal factors influencing the feasibility of LED-enhanced wastewater treatment. Overall, while LED technology offers notable productivity benefits, its economic and environmental trade-offs underscore the need for integrated approaches—ranging from material innovations to policy incentives—to achieve truly sustainable wastewater-based microalgal production