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Evaluation of 2,3-butanediol derived from whey fermentation as an effective bio-based monomer for waterborne polyurethane dispersions
Get PDFPublisher Copyright: Copyright © 2025 Germán-Ayuso, Cobos, Lorenzo, Río, Prieto-Fernández, Roncal and Cuevas.Within the context of the circular economy, the transformation of agri-food waste or by-products into valuable products is essential to promoting a transition towards more sustainable and efficient utilisation of resources. Whey is a very abundant by-product of dairy manufacturing. Apart from partial reutilisation in animal feed or some food supplements, the sustainable management and disposal of whey still represent significant environmental challenges. In this work, whey is considered a valuable resource for producing high-value products, specifically 2,3-butanediol (2,3-BDO), which was produced through fermentation using the bacterial strain Lactococcus lactis 43103. The described process yielded a >90% purity of 2,3-BDO, which was evaluated as a potential chain extender in the synthesis of bio-based waterborne polyurethane dispersions (PUDs). The incorporation of whey-derived 2,3-BDO led to the development of PUDs with up to 90% bio-based content without detrimental effects on the process or liquid-phase properties. The combination of 100% bio-based polyether polyols with partially renewable L-lysine ethyl ester diisocyanate and whey-derived 2,3-BDO as a chain extender generated totally stable, low-particle-size water dispersions of amorphous polymers characterised by similar structure and molecular weight compared to those of alternative petroleum-based PUDs. These results open up the possibility of incorporating fermentation-derived 2,3-BDO as a totally renewable component in bio-based PUDs as potential sustainable resinous systems for further formulation of water-based coatings or adhesives.Peer reviewe
Techno-Economic Evaluation of a Battery-as-a-Service Business Model in an Energy Community
No full textPublisher Copyright: © 2024 IEEE.The rise of Energy Communities (ECs) integrates various actors into low-voltage systems, including prosumers and local retailers. Battery usage in communities lacks exploration of Battery-as-a-Service (BaaS) models. This paper introduces a BaaS model in ECs, emphasising its benefits and impact on participants. A canvas model is proposed, and a case study is simulated in Spain to assess techno-economic and environmental advantages. Results show that the BaaS model reduced electricity bills by 6.8%, increased community P2P trading by 23.8%, and decreased CO2 emissions by 4.7%. However, the proposed model was not profitable for the community battery third-party owner in the current Spanish context. In a new tariff system where the power term was paid for use rather than availability, the BaaS model proved profitable and viable, recording a yearly profit of 1,800 € and outperforming the techno-economic and environmental indicators. The electricity bill diminished to 9.8 %, and CO2 emissions were reduced by 18.7 %.Peer reviewe
Advanced Solutions for Flexible Tools for Air-Craft Assembly: Lattice or Reticular Structures
No full textPublisher Copyright: © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.This contribution discusses the lack of modernization and automation in the tools used for assembling structures in the aeronautical industry, which is a disadvantage for the Basque industry's competitiveness. The paper suggests that significant innovation in these tools will result in savings in their development and subsequent maintenance during the production phase. To achieve this goal, the paper proposes the development of flexible and reconfigurable “fixtures” or columns, which can be used to manufacture large aerostructural components. The pa-per outlines specific requirements and needs for the structural design, such as flexibility, reusability, and rigidity. The paper also discusses the integration of the structure with robotics for automation and suggests that the new tool design should be prepared to integrate robotic applications for automated drilling and riveting. The ultimate goal is to differentiate Basque companies from others in the aeronautical industry and position the Spanish aeronautical sector in the international market by taking advantage of this innovative approach.Peer reviewe
Design, Fabrication, and Validation of Printed Embedded Antennas
No full textPublisher Copyright: © 2024 IEEE.This paper proposes a novel design for a printed and composite embedded UHF RFID dipole antenna operating at 868 MHz. The goal of this paper is to design an antenna that enables reliable communication between an RFID tag embedded in fiberglass epoxy resin and a reader. The antenna is printed on a fiberglass layer using conductive inks and embedded within an epoxy-reinforced composite. The design process considers factors like resonance frequency and impedance matching to achieve efficient communication with an RFID chip. Simulations were conducted to optimize the design for the chosen material properties and chip impedance. The fabricated antenna achieves a reading distance of 2.1 meters, demonstrating its functionality. While the reading distance is shorter than commercial antennas, this design offers advantages such as integration within composite materials for external protection. It also has the potential to incorporate additional functionalities like printed sensors and energy harvesting in future iterations.Peer reviewe
Purity: a New Dimension for Measuring Data Centralization Quality
Get PDFPublisher Copyright: © 2024 Copyright held by the owner/author(s).Data has become an asset for companies, originating from various sources, such as IoT paradigms. It is crucial to safeguard its life cycle using suitable, scalable, and effective technologies, like those enabled by cloud computing models. However, in order to extract value from this data, complementary processes of collection, refinement, cleaning, or modeling, among many others, are required. Furthermore, organizations greatly vary in their methodologies and approaches to handling data, which further emphasizes the need for standardized techniques. In this regard, data management methodologies promote the adoption of the various dimensions of data quality in order to ensure the reliability of data across different systems and processes. The main contribution of this manuscript is the proposal of a new data quality dimension, coined purity, to measure the importance of the data in a processing pipeline topology. As a result, organizations can better guarantee the quality of their datasets in order to raise the success of data-driven endeavors within organizations. The proposed methodology is validated in an urban mobility use case.Peer reviewe
Controller influence on the fatigue of a floating wind turbine and load case impact assessment
Get PDFPublisher Copyright: © 2024 Institute of Physics Publishing. All rights reserved.The assessment of fatigue in Floating Offshore Wind Turbines (FOWT) is a complex and widely debated topic within the industry. The dynamic behaviour of FOWT is heavily influenced by sea and wind conditions, which can significantly challenge the achievement of structural integrity and performance objectives. Additionally, the interaction of blade aerodynamics and control strategies further complicates this assessment. This study evaluates the impact of different control strategies and blade formulations on both the expected real performance and the estimated fatigue of FOWT. While control strategies can influence both the expected real performance and fatigue estimations, the blade formulation primarily affects the accuracy of performance estimations without altering the actual expected performance. However, the blade formulation can significantly modify the fatigue estimation of the FOWT. Damage Equivalent Loads (DEL) calculation is a commonly used method for assessing fatigue. However, while individual DEL calculations are useful, they do not show the contribution of each load case to the overall fatigue, since they do not consider the probability of occurrence. Therefore, this paper proposes a new method of normalising DEL, allowing for comparison of loading cases and identifying operational areas that pose greater fatigue risks. The findings underscore the substantial impact that different control strategies and blade designs can have on fatigue and overall performance. Essentially, there is a trade-off between maximising power output and minimising fatigue damage.Peer reviewe
Notch Effect in Acrylonitrile Styrene Acrylate (ASA) Single-Edge-Notch Bending Specimens Manufactured by Fused Filament Fabrication
Get PDFPublisher Copyright: © 2024 by the authors.This paper analyses the notch effect in the fracture behaviour of acrylonitrile–styrene–acrylate (ASA) material manufactured by fused filament fabrication (FFF). The research is performed on 72 single-edge-notch bending (SENB) specimens containing U-notches with nominal notch radii varying from 0 mm (crack-like defects) up to 2.0 mm, and fabricated with three different raster orientations (0/90, 45/−45, 30/−60). Apparent fracture toughness values are obtained for the different conditions and the resulting notch effect is analysed through the Theory of Critical Distances. A fractographic analysis is also performed using Scanning Electron Microscopy (SEM) in order to justify the fracture (macroscopic) behaviour from the observed fracture micromechanisms. The notch effect observed in the three ASA raster orientations is very similar, and lower than that observed in other FFF polymeric alternatives (ABS, PLA).Peer reviewe
Advances in understanding R3 chemical reactivity in various traditional and emerging pozzolans: Chemical, mineralogical and calorimetric dimensions
Get PDFPublisher Copyright: © 2024 The AuthorsDevelopment of the ASTM C1897-based R3 test facilitates faster, more accurate and more effective assessment of the chemical reactivity of natural and industrial pozzolans. While this methodology has been validated for conventional pozzolans (i.e. metakaolin, silica fume, fly ash, calcined clays and granulated slags), its robustness when applied to emerging eco-pozzolans has yet to be confirmed. This paper presents new evidence on chemical reactivity in a wide range of emerging supplementary cementitious materials (e.g. minerals recycled from construction and demolition waste, calcined paper sludge, biomass ash, rice husk ash and sugar cane bagasse ash) and statistically evaluates the consistency and correlation of methods A and B employed in R3 testing based on the different samples’ fundamental chemical composition (XRF) and amount of amorphous mineral content (XRD–Rietveld). The results reveal strong correlations between the amorphous material content of the 12 pozzolans examined and the cumulative heat release at 168 h (R2 = 87 %) and with methods A and B. An excellent correlation (R2 =99.7 %) is likewise evident between the combined water method and the thermogravimetry technique. Based on these findings, four ranges of chemical reactivity are proposed according to the cumulative heat release at 168 h (determined as per ASTM C1897 Method A): low 25–100 J/g; moderate 100–180 J/g; high 180–360 J/g and very high > 360 J/g. Finally, for certain types of biomass ash with high potash and sulphate content, the chemically combined water content is determined in two steps: (i) from 40 °C to 105 °C and (ii) from 105 °C to 350 °C, verifying that the B/A ratio exceeds 1.0.Peer reviewe
Advanced biotechnological processes to develop innovative probiotics with the ability to modulate intestinal microbiota
No full textPublisher Copyright: © 2025 Elsevier Inc. All rights reserved.There is constant research in biotechnological processes to develop delivery systems for drugs, nucleic acids, and other active compounds for different biomedical applications. Bacterial ghosts (BGs) are intact bacterial cell envelopes that are emptied of their interior contents by activation of channels located in the cell membrane. In this sense, BGs are currently being used as vaccine delivery systems and vaccine adjuvants. In addition, the possibility of using BGs as new delivery systems for drugs, active compounds, etc. is being investigated since they have inherent immunogenicity, which allows targeted administration of the compounds that are transported and controlled release. Accordingly, the use of BGs as carrier vehicles will make it possible to guarantee, on the one hand, that the drugs arrive at the place of interest without undergoing modifications due to external factors. On the other hand, it will allow to guarantee the release at the place of interest by the receptors of membrane possessed by BG. The use of probiotic bacteria to make BGs may have an additional beneficial effect on human/animal health. In recent years, different terms related to probiotic bacteria have appeared, and specifically, the term parabiotics encompasses nonviable probiotics, inactive probiotics, or ghost probiotics. Therefore, a new avenue of research within the field of probiotics is their use as a vehicle for the transport of beneficial compounds (such as drugs) to different tissues, such as the intestinal microbiota and its interrelationship with it. In addition, there are different routes of administration of these delivery systems, BG, through the mucous membranes (nasal cavity, gastrointestinal tract, and ocular administration) and intravenous injection.Peer reviewe