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Combining cellulose substrates and perovskites in sustainable solar cells is possible:a systematic literature review offering realistic solutions
No full textThe aim of this article is to provide direction for the advancement of cellulose films as sustainable substrates for perovskite solar cells (PSCs). Cellulose, the most abundant biopolymer on Earth, represents a viable, renewable alternative to glass and synthetic polymers when subjected to appropriate modifications. It can be customized via crosslinking, plasticization, and functionalization to increase flexibility and solvent resistance while decreasing gas permeation, surface roughness, and thermal expansion. The adoption of cellulose can drive transformative changes in PSC processing, facilitating the integration of sustainable electrode materials and greener alternatives to toxic solvents, as well as the replacement of high-temperature treatments. Although the literature contains numerous solutions to specific challenges, these findings are scattered across different fields and must be critically assessed for PSC suitability. In this article, we critically review alternative fabrication methods and form a step-by-step multidisciplinary strategy to alter both cellulose and PSC fabrication protocols for the development of sustainable next-generation solar cells.</p
Strategic niobium integration and thermomechanical processing in the advancement of novel CMnSiAlPMo TRIP-aided bainitic steel
No full textThis study examines the effects of niobium (Nb) addition and different thermomechanical controlled processing (TMCP) regimes on the flow stress behaviour and microstructure evolution of a newly developed CMnSiAlPMo TRIP-aided bainitic steel. TMCP tests were conducted with various hot deformation passes, followed by austempering at 400 °C for 10 min using a Gleeble 3800 thermomechanical simulator. Microstructures were analysed using scanning electron microscopy with electron backscattering diffraction and X-ray diffraction. Results showed that increasing the number of passes and reducing the final deformation temperature (FDT) enhanced the flow behaviour for both 0Nb and 0.05Nb alloys, with strain hardening being the dominant mechanism across all regimes. The four-pass regime with an FDT of 850 °C for the 0Nb alloy achieved the highest hardness (457 HV), attributed to grain refinement, which was more influential than the retained austenite fraction. For the 0.05Nb alloy, the two-pass regime at 1050 °C showed the highest hardness (428 HV), resulting from a lower retained austenite fraction. Additionally, Nb addition significantly refined the microstructure and increased the peak flow stress from 385 MPa to 421 MPa for the four-pass regime. The prior austenite grain size decreased from 23 to 12 μm in the single-pass regime, and the largest grain size in the cumulative grain size distribution (D90%) decreased from 8.45 to 7.49 μm.</p
A nodalization study on modeling the containment and reactor pool of an integral PWR
Get PDFThis study investigates the impact of nodalization of the containment and reactor pool of a small integral Pressurized Water Reactor (iPWR) using the MELCOR 2.2 code. The research focuses on Design 1 of the EU-funded SASPAM-SA project, featuring a containment partially submerged in the reactor pool. Two accident scenarios were analyzed: a Design Basis Accident (DBA) and a severe accident. The simulations were conducted with four different nodalizations: a detailed base model, a single-volume containment model, a single-volume pool model, and a single-volume model for both the containment and the pool. The results indicate that while detailed nodalization can simulate temperature stratification, its effect on the overall accident simulation results, pressures and fission product releases is limited. The findings suggest that differences between single-volume and more detailed nodalizations are relatively small, with the detailed nodalization providing slightly lower containment pressures during the DBA scenario due to more efficient heat transfer
Towards 2040:Collaborative approach in Finnish food systems transition
Get PDFThis article presents experimental research that engaged Finnish stakeholders in discussions on how to transition global food systems toward sustainability by 2040, addressing urgent challenges such as climate change, resource depletion and population growth. The study introduces the “Future Food Court Workshops,” which involved representatives from various sectors, including industry, public institutions, third-sector organizations, educational entities, and consumers. To guide these discussions, the research developed an integrated framework combining social design, foresight, technology, and business perspectives, aiming to anticipate emerging needs and societal transformations. The workshops employed “Five Dimensions of Futures Consciousness” model for qualitative analysis of the stakeholder engagement; the model was used explicitly to understand how participants conceptualized the future of food systems. The analysis revealed, for example, how participants experienced sustainability challenges, their capacity for future-oriented behavior, the impact of present actions on future outcomes and the role of emerging technologies reflecting values of the systems they serve. This research advances the field of futures studies by demonstrating an interdisciplinary approach to engaging stakeholders in sustainable food system transitions, and hopefully offers valuable insights for researchers, policymakers, and practitioners, underscoring the necessity of adopting sustainable practices to address pressing environmental concerns.</p
Towards 2040:Collaborative approach in Finnish food systems transition
No full textThis article presents experimental research that engaged Finnish stakeholders in discussions on how to transition global food systems toward sustainability by 2040, addressing urgent challenges such as climate change, resource depletion and population growth. The study introduces the “Future Food Court Workshops,” which involved representatives from various sectors, including industry, public institutions, third-sector organizations, educational entities, and consumers. To guide these discussions, the research developed an integrated framework combining social design, foresight, technology, and business perspectives, aiming to anticipate emerging needs and societal transformations. The workshops employed “Five Dimensions of Futures Consciousness” model for qualitative analysis of the stakeholder engagement; the model was used explicitly to understand how participants conceptualized the future of food systems. The analysis revealed, for example, how participants experienced sustainability challenges, their capacity for future-oriented behavior, the impact of present actions on future outcomes and the role of emerging technologies reflecting values of the systems they serve. This research advances the field of futures studies by demonstrating an interdisciplinary approach to engaging stakeholders in sustainable food system transitions, and hopefully offers valuable insights for researchers, policymakers, and practitioners, underscoring the necessity of adopting sustainable practices to address pressing environmental concerns.</p
An Intelligent Optimization-Based Residual Negative Magnitude Shaping Scheme for Vibration Control
No full textWith the rapid advancement of modern manufacturing, suppressing residual vibrations in flexible and underactuated systems has become a critical challenge. Input shaping (IS) has garnered attention for its effectiveness in mitigating vibrations and enhancing motion performance. However, existing input shapers typically encounter unavoidable time delays (TDs), modeling inaccuracies, ineffective multimodal suppression and poor adaptability, limiting their control performance. Targeting at overcome these critical issues, this article proposes an intelligent optimization-based residual negative magnitude (NM) shaping vibration (IRV) control scheme with two novel ideas: 1) employing a data-driven differential evolution (DE) algorithm to estimate system errors; and 2) designing a robust particle swarm optimization (PSO)-based residual negative magnitude (PR) shaper to reduce TDs and compensate for modeling inaccuracies in multimodal vibration systems, thereby enhancing control adaptability to diverse system configurations. To validate its performance, eight real-world datasets have been established and made publicly available. Empirical studies demonstrate that the proposed PR shaper outperforms state-of-the-art shapers, and the IRV scheme achieves significant vibration suppression, reducing maximum residual vibrations by at least 9.26% compared to conventional methods. These advancements substantially improve vibration control in precision systems.</p
A probabilistic-driven approach for early design quality risk and crux identification using non-Markovian stochastic Petri nets
No full textQuality risk analysis of high-process-oriented systems, which refers to their ability to achieve required tasks on time, receives little attention during the early conceptual design stage, primarily due to the high level of abstraction when the system form is not yet fully defined. Although several mathematical methods exist to address this issue, they are fragmented across domains and lack a unified integration into early design practice. To address this problem, this paper introduces a novel approach that models design problems as discrete events with output conflict representation, using the non-Markovian stochastic Petri net. The framework is further integrated with mathematical techniques, including semi-Markov performance evaluation, sensitivity analysis, and uncertainty analysis, to quantify quality risks and identify the design crux (the most critical design parameters). By incorporating Monte Carlo simulations, it facilitates designers and engineers with early insights and allows them to compare alternative design specifications. Its applicability is demonstrated through a case study on the conceptual development of a remote maintenance system for the In-Bioshield area of the EU-DEMO fusion power plant. Initial results showed potential in identifying quality risks, addressing key factors contributing to the design problem, and finding optimal design specifications in the early stages
Strategic Marketing Tensions in Sustainable Business Models: A Conceptual Approach Through Customer Value Propositions and Stewardship
Get PDFSustainable business models (SBMs) inherently involve tensions, which are contradictory or misaligned demands that companies must consider simultaneously. However, there is a gap in the literature regarding the relevance and linkage of these tensions to strategic marketing considerations, including positioning, competitiveness, differentiation, and a company's interaction with customers. This study aims to identify a set of tensions that arise in the strategic marketing of SBMs and to explore how these tensions can be responded to by companies. The study adopts a conceptual methodology, applying customer value propositions (CVPs) as a structured strategic marketing lens to explore tensions. Further, stewardship is suggested as an ontological approach that shapes the strategic marketing responses to tensions for the collective good of future generations. The resulting framework outlines how companies can embrace SBM tensions, including their hierarchical intensity, make sense of complexity and address the dominance of unsustainable models through strategic marketing mechanisms.</p
Depolymerisation of γ-Valerolactone Organosolv Lignins with Unsupported Molybdenum-Based Catalysts
No full textLignin is an attractive feedstock for a wide variety of applications ranging from aromatic chemicals and transportation fuels to resins and coatings. Emerging biorefinery concepts, like the organosolv process, enable the separation of all the lignocellulose components, and moreover, produce lignins of high quality and purity susceptible to valorisation by depolymerisation. In this work, we focus on the depolymerisation of lignins obtained by γ-valerolactone (GVL) organosolv fractionation of four biomass feedstocks, eucalyptus, white birch, sugarcane bagasse and Scots pine. We demonstrate that lignins extracted with the GVL process are depolymerised using unsupported molybdenum-based catalysts under reductive conditions in supercritical ethanol. As a result, over 90% yields of low-molecular-weight lignin oils are obtained with minimal char formation, yields of the aromatic monomers being 7–16 wt%. Furthermore, the design of experiments method is used to analyse the effect of depolymerisation conditions, catalyst, hydrogen loading and temperature, on the yields and properties of the product fractions. Notably, we show that the properties of the lignin oils and monoaromatics can be tuned towards the targeted application by modifying the depolymerisation conditions.</p
Capture of <i>Saprolegnia parasitica</i> Spores in Flow-Through Aquaculture:First Observations
No full textSaprolegniosis, typically induced by oomycete Saprolegnia parasitica, is one of the most difficult pathogens in fish and other aquatic animals in freshwater systems. It is especially harmful for the endangered species landlocked salmon (Salmo salar m. sebago). Currently, there are only few alternatives to prevent and treat saprolegniosis occurrences, which can lead to major fish deaths and financial losses at fish farms. In this study, surface-modified cellulose materials were used at an experimental flow-through fish farm rearing landlocked salmon, which often suffers from saprolegniosis occurrences. The results showed that the material's cationic surfaces were able to capture the spores of S. parasitica (experimental part I and part II). The cellulose material was chemically modified with a high density of cationic quaternary ammonium groups, which performed better than a material with a weak cationic charge by amino groups obtained via physisorption of chitosan on the surface, resulting in fewer S. parasitica spores in the rearing tank water (experimental part I). The results are promising and offer a novel method for controlling saprolegniosis occurrences without harmful chemicals. However, certain environmental conditions (in experimental part II) inhibited the detection method (real-time quantitative polymerase chain reaction) used for the detection of S. parasitica. This highlights the need for further method development for the detection of S. parasitica. Overall, the results are promising in terms of reducing S. parasitica spores in rearing water and further controlling saprolegniosis occurrences. More process optimization is required to achieve the method's full potential in industrial scale processes.</p