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European plaice (Pleuronectes platessa) in aquaculture – Nutritional, chemical, and physicochemical quality compared to wild stocks
Get PDFEuropean plaice (Pleuronectes platessa) is among Europe's top-consumed fish species, but wild stocks fluctuate and change their habitat due to drastic changes in climate. Their potential in aquaculture is under consideration, and therefore multiple quality aspects have been evaluated in this study. The chemical composition, nutritional profile, and physicochemical properties of European plaice (Pleuronectes platessa) from aquaculture and wild origin (Norwegian west-coast) and differences between female and male farmed individuals were studied. Differences between farmed and wild fish were found for the proximate composition, nutritional profile, and physicochemical attributes. Farmed fish generally had paler color (higher L*; 78.7 ± 4.2) but showed reduced water holding capacity (WHC; 80.3 ± 8.1%), but a firmer fillet texture compared to wild plaice. Farmed fish had significantly higher lipid and lower ash contents than wild individuals. Farmed fish's free amino acid (FAA) content (265.6 ± 59.0 mg/ 100 g) was significantly higher than in wild fish (89.72 ± 43.6 mg/ 100 g), especially the taste contributing FAA glutamate, glycine, alanine, and tyrosine. However, large individual varieties in FAA were observed within farmed and wild specimens. Farmed fish's fatty acid (FA) profile reflects the feed's composition. The overall quality of farmed European plaice was comparable to wild individuals with an excellent nutritional profile. Gender comparisons in farmed fish has shown that females were paler (higher L*) and showed higher hue (h) values, lower color saturation (Chroma, C), and yellowness (a*) compared to males. No apparent difference in texture was found, and no correlations between WHC and pH nor WHC and water content were detected between females and males. Farmed male individuals had higher lipid (2.35 ± 1.5%) and protein (16.97 ± 1.1%) concentrations compared to females (1.72 ± 1.1%; 15.52 ± 1.7%). The overall findings of this study are promising to further investigate this species for cultivation as a sustainable food resource.publishedVersio
Performance of a Cable-Driven Robot Used for Cyber–Physical Testing of Floating Wind Turbines
Get PDFCyber–physical testing has been applied for a decade in hydrodynamic laboratories to assess the dynamic performance of floating wind turbines (FWTs) in realistic wind and wave conditions. Aerodynamic loads, computed by a numerical simulator fed with model test measurements, are applied in real time on the physical model using actuators. The present paper proposes a set of short and targeted benchmark tests that aim to quantify the performance of actuators used in cyber–physical FWT testing. They aim at ensuring good load tracking over all frequencies of interest and satisfactory disturbance rejection for large motions to provide a realistic test setup. These benchmark tests are exemplified on two radically different 15 MW FWT models tested at SINTEF Ocean using a cable-driven robot.publishedVersio
Evaluating the Reaction Kinetics on the H2 Reduction of a Manganese Ore at Elevated Temperatures
Get PDFThis study investigates the hydrogen reduction of Nchwaning manganese ore at elevated temperatures to enhance understanding of reaction kinetics and optimize industrial applications. Experimental investigations were conducted across temperatures ranging from 600 °C to 900 °C to observe reduction behavior and identify rate determining steps. Thermogravimetric analysis (TGA) was employed to monitor manganese ore weight loss, facilitating precise measurement of reduction rates. Various kinetic models validated experimental outcomes for H2 reduction, revealing an apparent activation energy (Ea) of 65.76 kJ/mol and an apparent pre-exponential factor (k0) of 319.66 min⁻1. The rate constant (k) exhibited a significant temperature-dependent increase, following the Arrhenius equation where rates approximately doubled every 100 °C, rising from 0.037 min⁻1 at 600 °C to 0.377 min⁻1 at 900 °C. Morphological and compositional analyses using scanning electron microscopy (SEM) and X-ray diffraction (XRD) assessed structural changes post-reduction. Results demonstrated that pre-reduction temperature critically influences the physical and microstructural properties of the ore particles, particularly above 700 °C, where a notable reduction in BET (Brunauer–Emmett–Teller) surface area and pore volume indicated sintering within the ore. The rate determining step for this reduction process is most likely the chemical reaction at the gas–solid interface between hydrogen and the manganese ore. These findings highlight advancements in efficient manganese ore reduction processes, with significant implications for metallurgical practices and the hydrogen economy.publishedVersio
Full conversion to natural refrigerants - Feasible and likely to happen?
Get PDFThe paper reflects on answers to the question whether a full conversion to natural refrigerants is feasible from a holistic view based on technological, cost- and environmental perspectives. The reflections are partly based on developments in certain applications in a historical context, as well as in light of new frameworks, like the new EU F-gas directive and the outcome of COP28. The fact that refrigerants controlled by the Montreal Protocol and its Kigali-amendment is still very widespread in use for various applications makes it urgent to transition these to low-GWP refrigerants. The only longer-term solution based on fluorinated refrigerants is the unsaturated HFCs, commonly denoted as HFOs. These fluids are known to be PFAS substances contributing to TFA pollution when decomposed in the atmosphere. Based on the analysis, it may be envisioned that a full conversion to natural refrigerants is feasible and may also be the most adequate option. Keywords: Natural Refrigerants, Technological Feasibility, Refrigerant Options, Energy EfficiencyFull conversion to natural refrigerants - Feasible and likely to happen?acceptedVersio
Physics-based and data-driven modelling and simulation of Solid Oxide Fuel Cells
Get PDFThis paper presents a comprehensive approach to multiscale and multiphysics modelling of Solid Oxide Fuel Cells (SOFCs) by combining physics-based simulations with data-driven techniques. The modelling approach is tailored to specific end-use scenarios, ensuring that parameter selection aligns with operational requirements for accurate and efficient SOFC design. The study begins by constructing Representative Volume Elements ( s) from reconstructed microstructures, applying first-order homogenisation to upscale material properties, which are then incorporated into a macroscopic SOFC model. A major contribution is the structured model definition based on physical process entities, using a graphical representation of model topology. This approach simplifies complex system interactions by representing capacities (such as reservoirs, distributed systems, and interfaces) and transport processes (e.g., diffusion, convection, thermal diffusion), thereby enhancing clarity and improving the accuracy of SOFC performance simulations. A machine learning framework complements the physics-based modelling by training Artificial Neural Networks (ANNs) on simulation-generated datasets, delivering fast and reliable performance predictions. The study compares two optimisation techniques — Levenberg–Marquardt (LM) and Adam optimiser — demonstrating that LM is more effective for sparse datasets and smaller networks, whereas Adam performs better with large datasets and higher learning capacities. This hybrid modelling approach not only boosts predictive accuracy for SOFC performance but also lowers computational costs. By integrating physics-based simulations, machine learning, and a knowledge-driven simulation platform, this work advances SOFC design and optimisation, contributing to more efficient and cost-effective clean energy solutions. Additionally, the paper introduces a knowledge-driven simulation platform to enhance data management and integrate multiscale, multiphysics models. The platform leverages structured data models and ontological mappings to improve semantic interoperability, allowing for dataset reuse and validation across different simulation stages. This ensures a robust, reusable, and well-organised workflow, facilitating large-scale simulations and improving overall modelling accuracy.publishedVersio
Additive manufacturing of Proton-Conducting Ceramics by robocasting with integrated laser postprocessing
Get PDFA hybrid system combining robocasting and NIR laser postprocessing has been designed to fabricate layers of mixed proton-electron conducting Ba0.5La0.5Co1-xFexO3-δ ceramic. The proposed manufacturing technique allows for the control of the geometry and microstructure and shortens the fabrication time to a range of a few minutes. Using 5 W laser power and a scanning speed of 500 mm·s−1, sintering of a round-shaped layer with an 8 mm radius was performed in less than 2 s. The single phase of the final product was confirmed by X-ray diffraction. Various ceramic-to-polymer weight ratios were tested, showing that various porosities of microstructures of ∼30 - 35 % and ∼19 % can be obtained with 2:1 and 4:1 loading respectively.publishedVersio
Koala-UI: An Interactive User Interface for Tabular Data Linking
Get PDFThis paper introduces Koala-UI – a user interface system aimed at simplifying the entity linking process within data enrichment pipelines. Koala-UI provides an intuitive mechanism for linking entities across datasets, combining automation with human feedback to ensure accurate and consistent data. Koala-UI was successfully applied in use cases such as public procurement, where it enabled enrichment of a tenders dataset by linking entities to external knowledge graphs. Future developments will focus on expanding its backend to support additional models and enhance its human-in-the-loop capabilities.publishedVersio
Technological solutions for production of protein and lipid rich fractions from whitefish RRM - Deliverable 3.1
Get PDFThe work executed in the frame of WP3 of the SUPREME project indicated that a number of high-quality marine ingredients and products can be produced from white fish rest raw materials (RRM) by choosing the right preservation and processing technologies. Silaging of RRM from whitefish was proven to be a technological solution that can be used for preservation and short-term storage of raw material. Simple and inexpensive preservation technologies can be used for storage and transportation of whitefish skins, which then can be used for production of high-quality marine gelatine. Both collagen and gelatine can be extracted from collagen-rich whitefish RRM like bones and skins. Optimisation of gelatine extraction technologies indicated that thermally pre-treated backbones yield slightly higher amount of gelatine. There was no significant difference in quality or chemical and sensory characteristics of hydrolysates produced from cod head captured by trawl or longline: frozen cod heads from The Norwegian sea-going fleet can be an excellent source of high-quality proteins and this was proved by upscaled hydrolysis. Muscle removed form cod backbones can be used for production of taste neutral proteins, which are comparable with protein from other sources like whey and pea proteins.Technological solutions for production of protein and lipid rich fractions from whitefish RRM - Deliverable 3.1publishedVersio
