Search Results (10,320)

Bioelectromethanogenesis, the microbial conversion of carbon dioxide (CO₂) into methane (CH₄) using a cathode, offers a promising route for biogas upgrading and renewable energy storage. The flow field is an essential factor influencing the performance of bioelectromethanogenesis, and the stability and efficiency of the biocathode play important roles in this process. This study systematically investigated the effect of different internal-circulation flow rates on the biocathode initiated without the electric field and the reactor effluent. It was found that the methane production of the biocathode initiated without the electric field was increased by around 30% at an internal-circulation flow rate of 18 mL/min, which was stronger than that of the biocathode initiated by the reactor effluent. The relative content of the extracellular polymeric substance (EPS) heme was increased by 4%, while the EPS electron accepting capacity was much higher than that initiated by reactor effluent. Furthermore, the microbial community analysis showed that the functional methanogen on the biocathode initiated without an electric field was Methanosaeta (17%) and Methanobacterium (8%). This study could provide support for the dynamic operation of biogas upgrading in microbial electrolysis cells. Full article

Wastewater treatment plants (WWTPs) are increasingly considered critical infrastructure for environmental protection and combating climate change in regions suffering from severe water scarcity. The aim of this work is to provide a comprehensive and integrated evaluation of the performance of WWTPs in arid and hyperarid contexts, based on two representative experiences in the Algerian Sahara. The evaluation is based on an analysis of treatment performance (COD, BOD₅, TSS), operational stability, and the agricultural suitability of the wastewater (electrical conductivity, SAR, RSC), in addition to the indirect effects on groundwater protection. The results show high and stable organic matter removal rates (>85–90%), demonstrating the effectiveness of biological processes under harsh climatic conditions. Despite these benefits, residual salinity and sodium carbonate remain the two main factors limiting the extent of long-term agricultural reuse, despite effective treatment. The international comparative analysis highlights the systemic nature of this dissociation in hyperarid environments and emphasizes the need to consider wastewater treatment plants as truly integrated environmental barriers. Full article

Despite significant advancements in Artificial Intelligence, its widespread adoption in the clinical domain remains restricted due to the inherent complexity, fragmented nature, and diversity of healthcare systems. Each healthcare provider has unique data, clinical guidelines, data availability, system architectures, heterogeneity, and distribution. These challenges hinder the application of Clinical Decision Support Systems because of a limited understanding of how existing systems can be effectively redeployed across different healthcare providers. Redeployment is needed because it enables the reuse of existing knowledge, maximizes reusability, and avoids code duplication, thereby reducing the costs, effort, and time required to develop the Clinical Decision Support System from scratch. In addition, it ensures faster deployment and wider accessibility in the case of resource-constrained healthcare providers. An essential for redeployment is to identify the possible situations in which variables differ between two dynamic environments. To address this gap, we propose a structured multi-dimensional framework that systematically analyzes the potential differences between the variables. To represent the output of differences across dimensions based on variables in a systematic, machine-readable manner, we proposed a conceptual model, “VarDiff”, and a decision matrix of possible outcomes across five differential dimensions. This conceptual model provides a systematic, structural, and logical representation of a multidimensional framework for identifying differences among variables across data ecosystems. It formalizes variable characteristics in terms of semantic entities to observe differences among variables. The adaptation categories help identify the specific adaptation type, enabling the selection of relevant adaptation strategies in the “Mutator” component. Full article

The management of hazardous municipal solid waste incineration (MSWI) residues represents a critical challenge for sustainable development due to their increasing generation and environmental risk. At the same time, the cement industry faces urgent pressure to reduce CO₂ emissions associated with clinker production, creating a demand for alternative supplementary cementitious materials. The aim of this study was to evaluate the feasibility of valorising hazardous municipal solid waste incineration (MSWI) air pollution control fly ash (EWC 19 01 07*) as a constituent of Portland composite cement, in line with circular economy principles and the need to reduce CO₂ emissions associated with clinker production. The investigated fly ash, originating from flue gas cleaning processes, is characterised by high alkalinity and elevated concentrations of heavy metals, which currently necessitate controlled landfilling. To enable its safe reuse, the ash was subjected to high-temperature thermal treatment following granulation and subsequently incorporated into cement formulations under semi-industrial conditions. Two Portland composite cements were produced with different ash contents, corresponding to CEM II/A-07 and CEM II/B-07, while a Portland cement manufactured from the same clinker was used as a reference material. The chemical and phase composition of the ash before and after thermal treatment was analysed using XRF and XRD, supported by SEM/EDS observations. The results demonstrate that thermal treatment at 1150 °C induces partial phase stabilisation of APC fly ash without full vitrification, allowing its integration into cement systems under semi-industrial conditions. The incorporation of ash significantly alters hydration behaviour through increased water demand governed by particle porosity, CaO-rich phase composition, and early ionic interactions in the pore solution, leading to reduced workability and mechanical performance. While immobilisation efficiencies exceeding 99.5% were achieved for most heavy metals due to precipitation and incorporation into hydration products, barium exhibited persistent leaching controlled by its solubility under highly alkaline conditions and limited incorporation into C–S–H phases. These findings define both the technological feasibility and the key environmental constraints of APC fly ash utilisation in Portland composite cement. From a sustainability perspective, the proposed approach contributes to the reduction in hazardous waste landfilling and supports clinker substitution in cement production. The results demonstrate the potential of integrating waste management and low-carbon material design within a circular economy framework while highlighting current environmental limitations related to barium leaching. Full article

Traditionally, repairing coated substrates requires completely removing damaged, wear-resistant layers before recoating. This process leads to high costs, extended downtime, and material waste. Flexible brazing tapes, which are composed of alloy powder and an organic binder, offer an alternative to full coating removal for targeted repairs. Despite this, the process of vacuum brazing these tapes may lead to the formation of defects, including pores caused by trapped gases or residual binder, which compromise coating durability and corrosion resistance. This study focuses on the utilization of laser remelting as a method for post-processing nickel- and iron-based mixed alloy brazing tapes, with the aim of improving the integrity of the coating. Surface quality was assessed via microscopy and microhardness testing by systematically varying laser power, scanning speed, and hatch distance. Among the parameters studied, the most suitable laser parameter combination was found to be 350 W laser power, 250 mm/s scanning speed, and a hatch distance of 0.02 mm. These parameters yielded crack- and pore-free coatings with a remelting depth of 160.3 ± 17.2 µm and a microhardness of 701 ± 23 HV1, which is an 85% increase over as-brazed samples. Wear testing revealed a reduced coefficient of friction, and electrochemical corrosion tests showed lower corrosion current density and enhanced repassivation behavior in remelted coatings. These improvements demonstrate that laser remelting significantly enhances the microstructure, hardness, wear resistance, and corrosion performance of brazed coatings, providing an effective method for localized repair while minimizing material consumption and processing duration. Full article

The tractor road, as the core scene for autonomous driving of grain transport vehicles, is unstructured, complex, and obstacle-rich, leading to poor real-time performance and accuracy of joint road and obstacle detection with existing YOLOv5s. Furthermore, the reliability of passable area evaluation is low solely based on environmental factors. Therefore, YOLOv5s-C2S is proposed, fusing multi-scale features, attention mechanism, and dynamic features for joint detection. Firstly, YOLOv5s-CC is proposed for road detection by fusing context and spatial details and introducing Criss-Cross attention. Secondly, YOLOv5s-SGA is proposed for obstacle detection by grouped and spatial convolution, parameter-free attention, and adaptive feature fusion. By reusing YOLOv5s-CC weights, YOLOv5s-C2S shares low-level features and decouples high-level specificity. Based on the tractor road and obstacle information, combined with vehicle factors, a weighted scoring–based comprehensive method for passable area evaluation is proposed. Finally, the method was verified through experiments with an intelligent tracked grain transport vehicle using self-constructed datasets, including VOC_Road (11,927 images) and VOC_Obstacle (21,779 images). Compared with existing YOLOv5s, Deeplabv3+, FCN, Unet and SegNet, the mAP₅₀ of road detection by YOLOv5s-CC increased by over 1.2%. Compared with existing YOLOv5s, R-CNN, YOLOv7, SSD and YOLOv8n, the mAP₅₀ of obstacle detection by YOLOv5s-SGA increased by over 2%. Compared with YOLOv5s-SD, the mAP₅₀ of joint detection by YOLOv5s-C2S increased by 9.3%, and the frame rate increased by 7.0 FPS. The proposed passable area evaluation method exhibits strong robustness and reliability in complex environments, meeting the accuracy and real-time requirements in autonomous driving of grain transport vehicles. Full article

Imine reductases (IREDs) have emerged as valuable biocatalysts for the asymmetric synthesis of chiral amines, key intermediates in numerous active pharmaceutical ingredients. Their ability to operate under mild reaction conditions with high chemo- and stereoselectivity provides an attractive alternative to conventional metal-catalyzed or chemical reduction processes. However, the broader industrial application of wild-type IREDs is often constrained by their limited substrate scope and moderate catalytic efficiency. Recent advances in biocatalysis have demonstrated that engineered IREDs can catalyze the reduction of a wide range of natural and non-natural imines, significantly expanding their applicability in pharmaceutical and fine chemical synthesis. In parallel, enzyme immobilization strategies have proven highly effective for improving operational stability, facilitating enzyme reuse, and enabling continuous flow biocatalytic processes. Efficient cofactor regeneration systems have further enhanced the practical implementation of IRED-based transformations. Advances in protein engineering, including structure-guided design, semi-rational mutagenesis, and directed evolution, have generated enzyme variants with improved catalytic activity, stereoselectivity, and substrate tolerance. The integration of high-throughput screening technologies and machine-learning-assisted enzyme design has further accelerated the discovery and optimization of efficient IRED biocatalysts. This review summarizes recent progress in the protein engineering and immobilization of IREDs and discusses future perspectives for their industrial application. Full article

The reuse of treated wastewater for agricultural irrigation is increasingly considered a strategic response to water scarcity and climate change, particularly in Mediterranean regions. This study examines the local feasibility and social acceptance of water reuse within the framework of Regulation (EU) 2020/741, focusing on its implementation in Italy. The research combines policy analysis, technical assessment of effluent quality from the GIDA wastewater treatment plant (Prato, Tuscany), GIS-based spatial evaluation, and a mixed-method survey of local agri-food producers. Results show substantial compliance with EU minimum quality requirements, alongside additional constraints arising from national regulatory thresholds. Survey findings reveal cautious but tangible openness among farmers toward reclaimed water use, particularly in response to increasing climate-related pressures. The case of Prato is further analysed within the Prato Circular City and local food policy frameworks, highlighting the role of participatory governance and multi-actor engagement in supporting reuse initiatives. The study contributes empirical evidence on the interaction between EU regulation, national implementation measures, and local socio-institutional conditions shaping peri-urban water reuse systems. Furthermore, it serves as a preliminary framework for future economic feasibility studies and the subsequent regulatory and permitting phases required to operationalize this practice. Full article

The beneficial use of mining waste aligns with circular economy thinking: saving primary resources can extend their lifetime and maintain availability, reduce the volume of legacy mining waste and its environmental impacts, and develop a resource beneficiation industry that is less energy and water intensive; mining lower grades at larger scale inevitably requires more beneficial reuse. Existing classifications applicable to different types of mine waste were reviewed. These include factors such as the mode of origin during the mining operation, grain size, chemical composition and stability. The result shows that these factors also largely control their civil engineering applications, suitability for end use sectors and potential hazards. Long-term liabilities related to chemical stability were identified as the most difficult challenge. When developing a reuse project, either by the end users or by the mine operator, it is likely that resource screening covering a comprehensive range of factors will be required, as none of the existing schemes individually cover all of the aspects needed to fully assess suitability for beneficial use. In conclusion, there is a need for a systematic and structured approach to classification of mining waste to facilitate reuse as raw materials, such as that presented in our review. Full article

Fenton-based processes are widely used advanced oxidation methods that are known for degrading persistent pollutants. However, these techniques often generate significant amounts of iron-containing sludge, which poses environmental disposal challenges due to its complex composition. Furthermore, the sludge produced by the Fenton process contains a high content of Fe(III) compounds, which can serve as an iron source to stimulate dissimilatory iron reduction (DIR), enhancing the performance of anaerobic digestion. Based on the characterization results from a previous study, this work investigated the use of the ferrous precipitate generated by the electrochemical peroxidation process applied to tannery wastewater treatment as an additive to enhance volatile fatty acids (VFAs) production during dark fermentation. The performance of ferrous precipitate (R-Fe₃O₄) was compared to that of conventional magnetite (Fe₃O₄) during dark fermentation under high organic loading conditions, emphasizing their potential to enhance hydrolysis efficiency and VFAs production yields, while promoting sustainable resource recovery and reuse within a circular bioeconomy framework. The results showed that the addition of both Fe₃O₄ and R-Fe₃O₄ significantly increased the VFAs yields, with a predominance of long-chain fatty acids. The presence of CaCO₃ in the ferrous precipitate contributed to maintaining a stable pH environment, supporting microbial activity and enhancing the hydrolysis of soluble compounds. Moreover, the availability of essential micronutrients within the ferrous precipitate favored greater microbial diversity. Consequently, the addition of R-Fe₃O₄ promoted VFAs production, even at higher organic loading rates, suggesting a promising application of Fenton-based by-products as functional additives to improve the economic and environmental performance of the dark fermentation process. Full article

We explored the application of spatial information technology in the assessment and optimization of cultural heritage resources within traditional settlements in Meizhou City, a core area of Hakka culture in China. By integrating methods such as geographic information systems and Kernel density estimation, it systematically evaluates the spatial distribution and socioeconomic conditions of these settlements. A multi-criteria evaluation model is constructed to quantify resource endowment across cultural, historical, and ecological dimensions, with particular emphasis on key factors influencing conservation effectiveness, such as infrastructure and economic vitality. Combining field investigations and literature review, we propose adaptive reuse strategies and policy recommendations to enhance settlement resilience and balance cultural preservation with regional development. Their expected outcomes include the engineering of a multidimensional geographic database for traditional settlements, the establishment of a spatial decision-support framework for heritage infrastructure conservation, and the development of systematic optimization protocols integrated with China’s rural revitalization technical policies. These results provide a computational and methodological foundation for interdisciplinary research in sustainable cultural heritage management and smart rural engineering. Full article

This study presents a systematic literature review on the environmental impact of industrial applications of Rare Earth Elements (REEs), particularly those classified as Critical Raw Materials (CRMs), such as Neodymium alloys. These materials are key components of permanent magnets (PMs) used in electrical machines, including automotive applications, wind turbine generators, and various consumer electronics. A structured methodology began with a comprehensive search across multiple scientific databases utilizing primary and secondary keywords. Studies were selected through a multi-step process, including screening by title, abstract, and full-text review, ensuring the inclusion of relevant and high-quality research. This approach allowed for a rigorous and reproducible assessment of the literature. The review was conducted to address two central issues: the main environmental impacts of using rare earths in permanent magnets for electric motors, and the role of recycling and reuse strategies in reducing them. The review summarizes current knowledge on the life cycle environmental impacts of REEs, from extraction to end-of-life management, highlighting opportunities and challenges in recycling and reuse. While recycling can partially reduce environmental impact, significant gaps remain in efficiency and large-scale feasibility. The literature also emphasizes the substantial impacts of REEs in permanent magnets, including resource depletion, energy use, and emissions. Overall, the study highlights the need to integrate environmental considerations into the design and management of REE-containing systems and identifies research gaps to support more sustainable and efficient materials management. Full article

The purpose of this study is the exploration of the catalytic performance of a ZSM-5 zeolite produced from iron-rich fly ash, without any additional iron loading, in removing paracetamol via a heterogenous Fenton reaction. The structural and textural characterization by powder X-ray diffraction and N₂ adsorption isotherms showed that a pure ZSM-5 phase was synthesized, but lower crystallinity and textural parameters were obtained when compared with commercial ZSM-5. The XPS analysis revealed significant amounts of iron and yttrium, which enhanced the electronic properties of the samples’ surface when compared with iron-impregnated commercial ZSM-5. The catalytic reaction was followed through UV-spectroscopy and kinetic models were applied to the data; the best fit was obtained for a pseudo-first-order model. All fly ash-based zeolites showed increased paracetamol removal when compared with commercial iron-loaded ZSM-5, which may be attributed to the more disordered structure, able to accommodate large paracetamol species (dimers). On the other hand, the effect of yttrium on the electronic properties of iron sites may increase the ^●OH radical formation, thus increasing the paracetamol removal rate, despite the progressive drop on paracetamol removal upon regeneration–reuse cycles due to Fe leaching. Full article

Construction materials are the primary source of embodied carbon in long-span bridge projects, particularly for steel-intensive structures. This study presents an empirical construction-stage carbon footprint assessment of the Anhsin Bridge, an asymmetric cable-stayed steel truss bridge in Taiwan. Using the emission factor method in accordance with ISO 14067 and Taiwan Environmental Protection Administration guidelines, a cradle-to-gate (A1–A5 equivalent) system boundary was applied, covering material production, transportation, and on-site construction activities. Total construction-stage emissions were estimated at 55,349 tCO₂e, dominated by structural steel (51.8%), followed by reinforcing steel, concrete, and cement. Material-related emissions accounted for over 90% of the total, highlighting the critical role of material selection in embodied carbon reduction. Three practical mitigation strategies were evaluated using verified project data, as follows: 40% cement substitution with supplementary cementitious materials, optimized steel erection methods, and enhanced reuse of formwork and temporary works. The combined scenario achieved a 7.3% reduction in construction-stage emissions without compromising constructability. The findings demonstrate the effectiveness of material-oriented, constructability-aware strategies for reducing embodied carbon in steel-intensive bridge construction. Full article

The use of marginal sedimentary aggregates in pavement construction remains a major challenge in mountainous regions due to their high porosity, weak lamination planes, and susceptibility to moisture-induced deterioration. This study investigates the potential of low-density polyethylene (LDPE) plastic waste to enhance the engineering performance of laminated Miocene soft rock aggregates used in bituminous concrete. Aggregates sourced from the Surma Group (Bhuban Formation) in Mizoram, India, were characterized through physico-mechanical, geochemical, and mineralogical analyses to evaluate their durability and moisture sensitivity. X-ray fluorescence (XRF) analysis revealed elevated feldspar and total alkali contents (≈5.15%), indicating a mineralogical composition prone to hydrophilic behavior and stripping within bituminous mixtures. To mitigate these limitations, aggregates were coated with varying proportions of LDPE plastic using the dry process. An optimum LDPE content of 9% by weight of aggregate produced significant improvements in aggregate performance, resulting in a 70.03% reduction in Aggregate Impact Value (from 17.72% to 5.31%), a decrease in Los Angeles Abrasion Value from 42.93% to 31.45%, and an 89.82% reduction in water absorption (from 4.52% to 0.46%). The polymer coating effectively sealed lamination planes and reduced moisture ingress within the sedimentary structure. Bituminous concrete mixtures incorporating LDPE were further evaluated using Marshall stability and indirect tensile strength tests. The addition of 1.1% LDPE by weight of mix significantly enhanced moisture resistance. For mixtures with nominal maximum aggregate sizes (NMASs) of 13 mm and 19 mm, the Tensile Strength Ratio (TSR) increased from 52.59% and 58.58% in the control mixtures to 82.81% and 87.10%, respectively, thereby satisfying the minimum requirement of 80% specified by MoRTH. The results indicate that LDPE functions as a hydrophobic barrier and structural sealant that improves binder–aggregate adhesion and prevents stripping along weak lamination planes. The findings demonstrate that LDPE-modified bituminous concrete provides a sustainable and technically viable strategy for upgrading marginal sedimentary aggregates into durable pavement materials while simultaneously promoting the beneficial reuse of plastic waste. Full article