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Boosting softwood hemicellulose hydrolysis:Enzymes from a new fungi Penicillium rotoruae remarkably improve CTec-2 hydrolysis efficiency and reduce sugar production costs
No full textEconomic production of fermentable sugars from lignocellulosic biomass is critical for the biorefinery applications in the bioeconomy industry. This study demonstrates effective enzymatic hydrolysis of recalcitrant softwood using newly identified fungus Penicillium rotoruae. Initially, nineteen fungal isolates were screened on softwood galactoglucomannan (GGM), with nine showing strong responses in the liquid culture. Trichoderma viride, Penicillium rotoruae, and Amorphotheca resinae showed highest β-mannanase, β-mannosidase, and α-galactosidase activities. P. rotoruae demonstrated superior main chain cleaving enzyme activities, while A. resinae excelled in the side chain cleaving activity. The crude enzyme of P. rotoruae was evaluated on two Pinus radiata substrates. Using soluble GGM, P. rotoruae released 34.3 % monomeric sugars (32.1 g/L reducing sugars), outperforming commercial CTec-2 (22.9 % and 23.2 g/L respectively). Co-application of CTec-2 with P. rotoruae enzymes increased monomeric sugar yield to 56.3 %, with galactose, mannose, and glucose increasing 20-, 3.6-, and 2.2-fold respectively. Using insoluble pulp, co-application yielded 88 % of monomeric sugars (20.2 g/L reducing sugars) representing an increase of 20 % soluble sugars relative to CTec-2 used alone. Techno-economic analysis indicated an increase in annual EBITDA, a positive ROCE and sugar cost savings of NZD 125/t demonstrating significant economic potential for softwood biorefineries.</p
Exhaled CO<sub>2</sub> and aerosol dispersion on a cruise ship:Airflow and infection risk insights
No full textUnderstanding airborne pathogen transmission in cruise ship environments remains a critical challenge due to the confined nature of indoor spaces, high occupancy, and limited access for real-world experimentation. This study addresses the gap in empirical data on particulate matter and CO2 dynamics aboard operational cruise ships, providing a high-resolution dataset that can be used for the validation of Computational Fluid Dynamics (CFD) models and informing infection probability risk assessments. An experimental trial was designed for two mechanically ventilated cruise ship rooms (R01, R02), instrumented at ten locations under eight ventilation scenarios: R01 with 100 % (S1a) and 50 % (S1b) design flow rates; R02 with 100 % (S2a), 50 % (S2b) and 10 % (S2c) design flow rates; R01 with high aerosol rate and 50 % flow rate (S3); and R01 with an air purifier at maximum (S4a, 1300 m3 h−1) and minimum (S4b, 422 m3 h−1) clean air delivery rate (CADR). A live UK-EU cruise hosted the experimental trial. Particulate matter and CO2 concentration, temperature and relative humidity were collected using portable sensors to build a unique dataset to validate subsequent computational modelling of aerosol dispersion, infection probability and transmission prevention, mitigation and management (PMM) approaches in arbitrary passenger ship spaces. As expected, PM and CO2 were markedly reduced under 100 % design flow ventilation compared with 50 %. Maximum PM2.5 reductions were 84 % during background, 29 % in build-up, and 72 % in decay experimental phases. An air purifier further reduced particulate matter, with peak PM reductions of 57 % (PM10), 48 % (PM2.5), and 45 % (PM1). These findings offer practical guidance for optimising air quality management strategies in cruise ships and other high-occupancy spaces, besides providing a crucial high-resolution dataset for validating numerical modelling. Moreover, this study provides valuable insights into mechanically ventilated shipboard airflow behaviour.</p
Formation of coherent nanocomposite structure in nickel-aluminum alloys synthesized far from equilibrium
No full textThe present study reports on the structure formation in thin epitaxial nickel-aluminum films (Ni1-xAlx; Al atomic fraction x up to x = 0.24 ) grown on MgO ( 001 ) substrates by magnetron sputtering. Experimental and computational data demonstrate that for x &lt; 0.11 , the films exhibit the face-centered cubic random solid-solution Ni1-xAlx structure ( γ phase). Whereas in the range x = 0.11–0.24 the γ phase coexists with the ordered L 1 2 structure ( γ ′ phase). The two phases are homogenously intermixed forming a strained coherent nanocomposite , which exhibits a single lattice parameter that expands as the Al content increases. Isothermal annealing of films containing x = 0.14 of Al, coupled with structural and nano-mechanical characterization, reveal that the coherent nanocomposite retains its overall integrity for temperatures up to 673 K , while the film hardness increases from 5.5 GPa (as deposited films) to 6 GPa . Further increase of the annealing temperature to 873 K and 1073 K causes the coherent nanocomposite to dissolve into distinct γ and γ ′ phase domains and the hardness to decrease down to values of 4 GPa . These findings confirm the metastable nature of the as-deposited thin Ni1-xAlx alloy films and underpin the effectiveness of high supersaturation/undercooling for creating non-equilibrium phases and self-organized nanostructures upon synthesis of multicomponent materials.</p
Impact pathways:geo-operations for turning plastic waste into carbon capture
No full textPurpose – We explore how an operations and supply chain approach to geo-engineering can enhance circular economy approaches and mitigate climate change. We illustrate how such geo-operations – specifically the combination of plastics and biowaste processing – can be systematically leveraged for carbon capture. Design/methodology/approach – The study applies production theory and operations management perspectives to develop a carbon transfer model. It traces carbon flows through the extended plastics supply chain and interconnected natural systems, from raw material inputs, through production and reuse cycles, to the ultimate disposal. By mapping carbon transfers between natural systems and artificial systems, the framework highlights the systemic impact pathways for operations and supply chain management. Findings – Single interventions such as bio-based materials, chemical recycling or policy instruments have limited impact in isolation. However, when combined systemically, these individual solutions can form geo-engineering operational pathways that draw out atmospheric carbon and refossilize it, thus transforming the plastics technosphere from a source of emissions to a means for carbon capture. Research limitations/implications – The study is conceptual and develops theoretical propositions on systemic impact, rather than presenting empirical findings. Future research should empirically investigate the feasibility, scale and trade-offs of the proposed geo-operations pathways. Practical implications – The carbon transfer model and impact pathways guide policymakers, producers and waste managers on integrating the circular economy and geo-operations for climate change mitigation and carbon capture. Social implications – By reframing plastics not only as a source of problematic waste but also as a possible vehicle for climate mitigation, the paper suggests new opportunities and responsibilities for industry and society. Originality/value – This paper proposes the development of geo-operations as a systemic pathway for integrating circular economy and carbon sequestration interventions. It also presents a framework to assess the impact of combinations of interventions on carbon flows.</p
A novel real-time noise-resilient zeroing neural network and its applications to matrix problem solving
No full textGiven the critical role of zeroing neural networks (ZNN) in various fields and the practical demand for models in effectively resisting real-time noise, this study introduces a novel anti-noise integral zeroing neural network (AN-IZNN) model alongside its enhanced counterpart (EAN-IZNN), for the applications of matrix problem solving. Theoretical analysis demonstrates their ability to achieve convergence even under different noise conditions. Both theoretical analyses and simulation validations highlight the superior performance of the proposed models over existing neural network models. Notably, the root mean square error of the proposed AN-IZNN and EAN-IZNN models is reduced by 92.6249% and 91.4178%, respectively, compared to scenarios without the proposed method, demonstrating the effectiveness of the solution.</p
Searching for a needle in a haystack - Sampling the ultra-low biomass deep subsurface environment for microbiology from the ultra-deep drillholes in Otaniemi, Finland
No full textIntegrated nuclear power planning and modeling framework:a pathway toward energy security, sustainable governance and net-zero-driven policy
No full textNuclear power presents a viable solution to overcome climate issues while ensuring energy security and sustainable governance. By addressing public concerns, investing in innovative technologies, and implementing supportive policies, nations can harness the potential of nuclear power to create a sustainable and resilient energy future. Hence, this study suggested increasing the share of nuclear power around 30% in total energy mix of Pakistan by 2030 and forecast the future until 2050. LEAP software is used to forecast the future of nuclear power from the period 2024 to 2050 by using the base year 2023 and suggested the energy balance with complete energy flows along with transmission and distribution losses. The results revealed that the share of nuclear power is increasing from 8.4% in 2024 to 42.4% until 2035, 57.9% until 2045, and 59.4% until 2050. The total energy generation for Pakistan in 2024 is 181.63 TWh which is sufficient to meet energy demand of 173.40 TWh. Subsequently, energy generation would be 399.42 TWh in 2035 and 1,135 TWh in 2050 which is sufficient to meet the energy demand of 337 TWh in 2035 and 965 TWh in 2050, respectively.</p
On diffusion-controlled Li-trapping in high energy Li-ion cells under fast discharge and freezing conditions
No full textLi-ion batteries are promising energy storage devices owing to their high energy density which enables their use in different applications. Herein, we report on the electrochemical behavior of commercial high capacity 30 Ah pouch cells with energy density 275 Wh kg−1 over a wide temperature range (60 °C to −20 °C) using different discharging rates. A testing protocol was designed to understand the losses seen in discharge capacities (reduction charges) when the cells were discharged at fast rates (~16 % and 20 % capacity losses at discharge rates of 2C and 3C, respectively) or operated under freezing conditions (~17 % capacity loss at ~ −20 °C and C/5 discharge rate). The protocol involved monitoring the charge capacity (oxidation charge) before and after discharging as well as tracking the changes in open circuit voltage (OCV) for about 30 min after discharging. The accessible capacity was concluded to be limited not only by the developed iR-drop, but also by the diffusion-controlled lithium trapping as a result of the formation of concentration gradient of Li-ions. Notably, the surface temperatures of the cells were raised from 25 °C (environmental chamber temperature) to ~40 °C and 52 °C upon fast discharge at rates of 2C and 3C, respectively. Resting the cells for about 30 min after fast discharge was sufficient to drop the surface temperature back to 25 °C. This work provides insights for understanding the limitations of fast discharge and operating temperatures on industry relevant high energy Li-ion battery cells.</p
Developing EU-CEM:A Common Evaluation Methodology for Evaluating Co-operative, Connected and Automated Mobility
No full textCo-operative, Connected and Automated Mobility (CCAM) is of increasing interest to the transport community across the world, though is still maturing. The Horizon Europe project FAME is developing a European framework for testing CCAM on public roads. As part of this, a common evaluation methodology (EU-CEM) is being developed, which provides guidance on how to set up and carry out an evaluation or assessment of direct and indirect impacts of CCAM solutions on different user groups and wider society. Objectives include ensuring that evaluations can be complementary planned with results that are easy to compare, as well as establishing a common vocabulary to support projects in the CCAM community. This paper sets out how the EU-CEM is being developed and embedded into CCAM research in Europe, with a particular emphasis on how the project has adopted an agile and iterative approach to the CEM development alongside meaningful and sustained engagement with stakeholders.</p