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Search Results (317)

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Keywords = external recycle

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15 pages, 1527 KiB  
Article
Marine-Inspired Ovothiol Analogs Inhibit Membrane-Bound Gamma-Glutamyl-Transpeptidase and Modulate Reactive Oxygen Species and Glutathione Levels in Human Leukemic Cells
by Annalisa Zuccarotto, Maria Russo, Annamaria Di Giacomo, Alessandra Casale, Aleksandra Mitrić, Serena Leone, Gian Luigi Russo and Immacolata Castellano
Mar. Drugs 2025, 23(8), 308; https://doi.org/10.3390/md23080308 - 30 Jul 2025
Viewed by 134
Abstract
The enzyme γ-glutamyl transpeptidase (GGT), located on the surface of cellular membranes, hydrolyzes extracellular glutathione (GSH) to guarantee the recycling of cysteine and maintain intracellular redox homeostasis. High expression levels of GGT on tumor cells are associated with increased cell proliferation and resistance [...] Read more.
The enzyme γ-glutamyl transpeptidase (GGT), located on the surface of cellular membranes, hydrolyzes extracellular glutathione (GSH) to guarantee the recycling of cysteine and maintain intracellular redox homeostasis. High expression levels of GGT on tumor cells are associated with increased cell proliferation and resistance against chemotherapy. Therefore, GGT inhibitors have potential as adjuvants in treating GGT-positive tumors; however, most have been abandoned during clinical trials due to toxicity. Recent studies indicate marine-derived ovothiols as more potent non-competitive GGT inhibitors, inducing a mixed cell-death phenotype of apoptosis and autophagy in GGT-overexpressing cell lines, such as the chronic B leukemic cell HG-3, while displaying no toxicity towards non-proliferative cells. In this work, we characterize the activity of two synthetic ovothiol analogs, L-5-sulfanylhistidine and iso-ovothiol A, in GGT-positive cells, such as HG-3 and HL-60 cells derived from acute promyelocytic leukemia. The two compounds inhibit the activity of membrane-bound GGT, without altering cell vitality nor inducing cytotoxic autophagy in HG-3 cells. We provide evidence that a portion of L-5-sulfanylhistidine enters HG-3 cells and acts as a redox regulator, contributing to the increase in intracellular GSH. On the other hand, ovothiol A, which is mostly sequestered by external membrane-bound GGT, induces intracellular ROS increase and the consequent autophagic pathways. These findings provide the basis for developing ovothiol derivatives as adjuvants in treating GGT-positive tumors’ chemoresistance. Full article
(This article belongs to the Special Issue Marine-Derived Novel Antioxidants)
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15 pages, 677 KiB  
Article
Zero-Shot Learning for Sustainable Municipal Waste Classification
by Dishant Mewada, Eoin Martino Grua, Ciaran Eising, Patrick Denny, Pepijn Van de Ven and Anthony Scanlan
Recycling 2025, 10(4), 144; https://doi.org/10.3390/recycling10040144 - 21 Jul 2025
Viewed by 270
Abstract
Automated waste classification is an essential step toward efficient recycling and waste management. Traditional deep learning models, such as convolutional neural networks, rely on extensive labeled datasets to achieve high accuracy. However, the annotation process is labor-intensive and time-consuming, limiting the scalability of [...] Read more.
Automated waste classification is an essential step toward efficient recycling and waste management. Traditional deep learning models, such as convolutional neural networks, rely on extensive labeled datasets to achieve high accuracy. However, the annotation process is labor-intensive and time-consuming, limiting the scalability of these approaches in real-world applications. Zero-shot learning is a machine learning paradigm that enables a model to recognize and classify objects it has never seen during training by leveraging semantic relationships and external knowledge sources. In this study, we investigate the potential of zero-shot learning for waste classification using two vision-language models: OWL-ViT and OpenCLIP. These models can classify waste without direct exposure to labeled examples by leveraging textual prompts. We apply this approach to the TrashNet dataset, which consists of images of municipal solid waste organized into six distinct categories: cardboard, glass, metal, paper, plastic, and trash. Our experimental results yield an average classification accuracy of 76.30% with Open Clip ViT-L/14-336 model, demonstrating the feasibility of zero-shot learning for waste classification while highlighting challenges in prompt sensitivity and class imbalance. Despite lower accuracy than CNN- and ViT-based classification models, zero-shot learning offers scalability and adaptability by enabling the classification of novel waste categories without retraining. This study underscores the potential of zero-shot learning in automated recycling systems, paving the way for more efficient, scalable, and annotation-free waste classification methodologies. Full article
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27 pages, 1046 KiB  
Review
Best Practices for Environmental Sustainability in Healthcare Simulation Education: A Scoping Review
by Jessica E. Marsack, Deborah Lee, Linda M. DiClemente, Melissa Bodi, Kimberley Clarke, Elizabeth S. Robison, Sandra Turnau, Laura Van Horn and Melissa A. Bathish
Sustainability 2025, 17(14), 6624; https://doi.org/10.3390/su17146624 - 20 Jul 2025
Viewed by 527
Abstract
Educators must understand current practices and gaps in knowledge regarding environmental sustainability in simulation education to reduce the environmental impact of plastic waste while still maintaining fidelity in simulation education. Therefore, a scoping review was conducted to answer the PICO question, “In healthcare [...] Read more.
Educators must understand current practices and gaps in knowledge regarding environmental sustainability in simulation education to reduce the environmental impact of plastic waste while still maintaining fidelity in simulation education. Therefore, a scoping review was conducted to answer the PICO question, “In healthcare institutions and hospitals, what are the environmentally sustainable practices that can be translated into simulation labs as best practice?” Fourteen studies were identified through a search of seven databases, critically appraised, and analyzed. Three key themes emerged: (1) the 5 R’s, (2) getting people motivated, and (3) larger external collaboration. These themes highlight practical strategies and motivational factors for sustainable practices. An expanded 5 R’s framework (reduce, reuse, recycle, research, and rethink) was introduced to guide a holistic approach. The literature highlights the importance of education, stakeholder engagement, and clearly defined standards as key drivers for motivating individuals and teams to engage in sustainable behaviors. These efforts are most effective when supported by interdisciplinary collaboration, regulatory frameworks, national policies, and technological innovation. Sustainability initiatives should extend beyond individual institutions to foster broader systemic change. Full article
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18 pages, 1422 KiB  
Article
Potable Water Recovery for Space Habitation Systems Using Hybrid Life Support Systems: Biological Pretreatment Coupled with Reverse Osmosis for Humidity Condensate Recovery
by Sunday Adu, William Shane Walker and William Andrew Jackson
Membranes 2025, 15(7), 212; https://doi.org/10.3390/membranes15070212 - 16 Jul 2025
Viewed by 554
Abstract
The development of efficient and sustainable water recycling systems is essential for long-term human missions and the establishment of space habitats on the Moon, Mars, and beyond. Humidity condensate (HC) is a low-strength wastewater that is currently recycled on the International Space Station [...] Read more.
The development of efficient and sustainable water recycling systems is essential for long-term human missions and the establishment of space habitats on the Moon, Mars, and beyond. Humidity condensate (HC) is a low-strength wastewater that is currently recycled on the International Space Station (ISS). The main contaminants in HC are primarily low-molecular-weight organics and ammonia. This has caused operational issues due to microbial growth in the Water Process Assembly (WPA) storage tank as well as failure of downstream systems. In addition, treatment of this wastewater primarily uses adsorptive and exchange media, which must be continually resupplied and represent a significant life-cycle cost. This study demonstrates the integration of a membrane-aerated biological reactor (MABR) for pretreatment and storage of HC, followed by brackish water reverse osmosis (BWRO). Two system configurations were tested: (1) periodic MABR fluid was sent to batch RO operating at 90% water recovery with the RO concentrate sent to a separate waste tank; and (2) periodic MABR fluid was sent to batch RO operating at 90% recovery with the RO concentrate returned to the MABR (accumulating salinity in the MABR). With an external recycle tank (configuration 2), the system produced 2160 L (i.e., 1080 crew-days) of near potable water (dissolved organic carbon (DOC) < 10 mg/L, total nitrogen (TN) < 12 mg/L, total dissolved solids (TDS) < 30 mg/L) with a single membrane (weight of 260 g). When the MABR was used as the RO recycle tank (configuration 1), 1100 L of permeate could be produced on a single membrane; RO permeate quality was slightly better but generally similar to the first configuration even though no brine was wasted during the run. The results suggest that this hybrid system has the potential to significantly enhance the self-sufficiency of space habitats, supporting sustainable extraterrestrial human habitation, as well as reducing current operational problems on the ISS. These systems may also apply to extreme locations such as remote/isolated terrestrial locations, especially in arid and semi-arid regions. Full article
(This article belongs to the Special Issue Advanced Membranes and Membrane Technologies for Wastewater Treatment)
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36 pages, 1973 KiB  
Article
A Comparative Life Cycle Assessment of an Electric and a Conventional Mid-Segment Car: Evaluating the Role of Critical Raw Materials in Potential Abiotic Resource Depletion
by Andrea Cappelli, Nicola Stefano Trimarchi, Simone Marzeddu, Riccardo Paoli and Francesco Romagnoli
Energies 2025, 18(14), 3698; https://doi.org/10.3390/en18143698 - 13 Jul 2025
Viewed by 568
Abstract
Electric passenger vehicles are set to dominate the European car market, driven by EU climate policies and the 2035 ban on internal combustion engine production. This study assesses the sustainability of this transition, focusing on global warming potential and Critical Raw Material (CRM) [...] Read more.
Electric passenger vehicles are set to dominate the European car market, driven by EU climate policies and the 2035 ban on internal combustion engine production. This study assesses the sustainability of this transition, focusing on global warming potential and Critical Raw Material (CRM) extraction throughout its life cycle. The intensive use of CRMs raises environmental, economic, social, and geopolitical concerns. These materials are scarce and are concentrated in a few politically sensitive regions, leaving the EU highly dependent on external suppliers. The extraction, transport, and refining of CRMs and battery production are high-emission processes that contribute to climate change and pose risks to ecosystems and human health. A Life Cycle Assessment (LCA) was conducted, using OpenLCA software and the Ecoinvent 3.10 database, comparing a Peugeot 308 in its diesel and electric versions. This study adopts a cradle-to-grave approach, analyzing three phases: production, utilization, and end-of-life treatment. Key indicators included Global Warming Potential (GWP100) and Abiotic Resource Depletion Potential (ADP) to assess CO2 emissions and mineral resource consumption. Technological advancements could mitigate mineral depletion concerns. Li-ion battery recycling is still underdeveloped, but has high recovery potential, with the sector expected to expand significantly. Moreover, repurposing used Li-ion batteries for stationary energy storage in renewable energy systems can extend their lifespan by over a decade, decreasing the demand for new batteries. Such innovations underscore the potential for a more sustainable electric vehicle industry. Full article
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14 pages, 5672 KiB  
Article
Numerical Study of the Combustion-Flow-Thermo-Pyrolysis Process in an Innovative Externally Heated Oil Shale Retort
by Lixin Zhao, Yingxue Mei and Luwei Pan
Symmetry 2025, 17(7), 1055; https://doi.org/10.3390/sym17071055 - 3 Jul 2025
Viewed by 322
Abstract
A novel externally heated retort for Jimsar oil shale resources is proposed, and the symmetrical mathematical model of the transport process in the retort is established through intensively studying the mechanisms of shale gas flows, heat transfer, and pyrolysis reactions in the retort. [...] Read more.
A novel externally heated retort for Jimsar oil shale resources is proposed, and the symmetrical mathematical model of the transport process in the retort is established through intensively studying the mechanisms of shale gas flows, heat transfer, and pyrolysis reactions in the retort. The descriptions of axial and radial movements and temperature of oil shale and gases, and the distribution of pyrolysis reaction and yielding of gaseous products and semi-coke in various regions of the retort are simulated. The results show that oil shale can pyrolyze gradually from the region near the wall to the core region of the retorting chamber and pyrolyze completely at the bottom of the retorting zone through receiving the heat flux transferring from the combustion channels. The final pyrolysis temperature of oil shale is 821.05 K, and the outlet temperature of semi-coke cooled by cold recycled gas is 676.35 K, which are in agreement with the design requirements. In total, 75 toil shales can be retorted in one retorting chamber per day, and the productivity of the retort can be increased by increasing the number of retorting chambers. The fuel self-sufficiency rate of this externally heated oil shale retort can reach 82.83%. Full article
(This article belongs to the Section Engineering and Materials)
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25 pages, 5796 KiB  
Article
Enhancing Sustainability and Functionality with Recycled Materials in Multi-Material Additive Manufacturing
by Nida Naveed, Muhammad Naveed Anwar, Mark Armstrong, Furqan Ahmad, Mir Irfan Ul Haq and Glenn Ridley
Sustainability 2025, 17(13), 6105; https://doi.org/10.3390/su17136105 - 3 Jul 2025
Viewed by 448
Abstract
This study presents a novel multi-material additive manufacturing (MMAM) strategy by combining virgin polylactic acid (vPLA) with recycled polylactic acid (rPLA) in a layered configuration to improve both performance and sustainability. Specimens were produced using fused deposition modelling (FDM) with various vPLA: rPLA [...] Read more.
This study presents a novel multi-material additive manufacturing (MMAM) strategy by combining virgin polylactic acid (vPLA) with recycled polylactic acid (rPLA) in a layered configuration to improve both performance and sustainability. Specimens were produced using fused deposition modelling (FDM) with various vPLA: rPLA ratios (33:67, 50:50, and 67:33) and two distinct layering approaches: one with vPLA forming the external layers and rPLA as the core, and a second using the reversed arrangement. Mechanical testing revealed that when vPLA is used as the exterior, printed components exhibit tensile strength and elongation improvements of 10–25% over conventional single-material prints, while the tensile modulus is largely influenced by the distribution of the two materials. Thermal analysis shows that both vPLA and rPLA begin to degrade at approximately 330 °C; however, rPLA demonstrates a higher end-of-degradation temperature (461.7 °C) and increased residue at elevated temperatures, suggesting improved thermal stability due to enhanced crystallinity. Full-field strain mapping, corroborated by digital microscopy (DM) and scanning electron microscopy (SEM), revealed that vPLA-rich regions display more uniform interlayer adhesion with minimal voids or microcracks, whereas rPLA-dominated areas exhibit greater porosity and a higher propensity for brittle failure. These findings highlight the role of optimal material placement in mitigating the inherent deficiencies of recycled polymers. The integrated approach of combining microstructural assessments with full-field strain mapping provides a comprehensive view of interlayer bonding and underlying failure mechanisms. Statistical analysis using analysis of variance (ANOVA) confirmed that both layer placement and material ratio have a significant influence on performance, with high effect sizes highlighting the sensitivity of mechanical properties to these parameters. In addition to demonstrating improvements in mechanical and thermal properties, this work addresses a significant gap in the literature by evaluating the combined effect of vPLA and rPLA in a multi-material configuration. The results emphasise that strategic material distribution can effectively counteract some of the limitations typically associated with recycled polymers, while also contributing to reduced dependence on virgin materials. These outcomes support broader sustainability objectives by enhancing energy efficiency and promoting a circular economy within additive manufacturing (AM). Overall, the study establishes a robust foundation for industrial-scale implementations, paving the way for future innovations in eco-efficient FDM processes. Full article
(This article belongs to the Special Issue 3D Printing for Multifunctional Applications and Sustainability)
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18 pages, 2954 KiB  
Article
Effect of Rubber Granulate Content on the Compressive Strength of Concrete for Industrial Vibration-Isolating Floors
by Maciej Gruszczyński, Alicja Kowalska-Koczwara and Tadeusz Tatara
Materials 2025, 18(13), 3134; https://doi.org/10.3390/ma18133134 - 2 Jul 2025
Viewed by 332
Abstract
Ensuring vibration and impact isolation is crucial in industrial flooring design, especially where vibroacoustic comfort is a priority. Excessive vibrations can negatively affect sensitive equipment, structural durability, and personnel comfort. With the rise of automation and high-precision processes, effective vibration control in floor [...] Read more.
Ensuring vibration and impact isolation is crucial in industrial flooring design, especially where vibroacoustic comfort is a priority. Excessive vibrations can negatively affect sensitive equipment, structural durability, and personnel comfort. With the rise of automation and high-precision processes, effective vibration control in floor systems is increasingly important. Traditional solutions like elastomer pads, rubber mats, or floating floors often have high installation costs, complex construction, and long-term degradation. Therefore, there is growing interest in integrated, durable alternatives that can be incorporated directly into concrete structures. One such approach uses rubber granulates from recycled tires as a modifying additive in cementitious composites. This can improve damping, enhance impact energy absorption, and reduce the need for external insulating layers. However, adding rubber particles to concrete may affect its compressive strength, a key design parameter. This article presents experimental research on concrete and mortar mixtures modified with rubber granulates for vibration-isolating industrial floor systems. The proposed solution combines a conventional concrete subbase with a rubber-enhanced mortar layer, forming a composite system to mitigate vibration transmission. Laboratory tests and real-scale verification under industrial conditions showed that the slab with hybrid EPDM/SBR rubber granulate mortar achieved the highest vibration-damping efficiency, reducing vertical acceleration by 58.6% compared to the reference slab. The EPDM-only mortar also showed a significant reduction of 45.5%. Full article
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20 pages, 445 KiB  
Review
Information Barriers to Circularity for Electronic Products and the Potential of Digital Product Passports
by Eduard Wagner
Sustainability 2025, 17(12), 5554; https://doi.org/10.3390/su17125554 - 17 Jun 2025
Viewed by 758
Abstract
Digitalisation is seen as an enabler of the circular economy that supports the flow of information important for the decision-making of consumers and recyclers. However, barriers prevail that hinder the effective implementation of circular economy practices. This study analyses prevailing circular economy barriers [...] Read more.
Digitalisation is seen as an enabler of the circular economy that supports the flow of information important for the decision-making of consumers and recyclers. However, barriers prevail that hinder the effective implementation of circular economy practices. This study analyses prevailing circular economy barriers and identifies information barriers along the product life cycle for the electronics sector. The digital product passport (DPP) is used as a concept to discuss the potentials and limitations for overcoming identified information barriers. A literature analysis was performed, extracting 77 information barriers from 17 selected articles. Results reveal gaps in missing information, including material composition and dismantling instructions for recyclers, product condition for second-hand consumers, certifications and know-how for designers, and deficiencies in internal and external communication. Several barriers of a technical, economic, or social nature are found that are indirectly rooted in missing information or knowledge. As a novelty, this study provides a comprehensive overview of information barriers along the product life cycle for the circular economy, considering the scope of the DPP. Practical implications are derived for further research, e.g., to evaluate which information should or has to be included in the DPP considering the data gathering effort, environmental benefits, and corporate interests. Full article
(This article belongs to the Section Environmental Sustainability and Applications)
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24 pages, 2822 KiB  
Review
Green Pathways: Enhancing Amine Synthesis Using Deep Eutectic Solvents
by Andrés R. Alcántara and Gonzalo de Gonzalo
Catalysts 2025, 15(6), 586; https://doi.org/10.3390/catal15060586 - 12 Jun 2025
Viewed by 2965
Abstract
Deep eutectic solvents (DESs) have emerged as prominent, environmentally benign substitutes for traditional solvents and catalysts in organic synthesis, notably in the synthesis of amines, pivotal structures in many industrial sectors. Their distinctive physicochemical attributes—including negligible volatility, exceptional thermal stability, and adjustable polarity—render [...] Read more.
Deep eutectic solvents (DESs) have emerged as prominent, environmentally benign substitutes for traditional solvents and catalysts in organic synthesis, notably in the synthesis of amines, pivotal structures in many industrial sectors. Their distinctive physicochemical attributes—including negligible volatility, exceptional thermal stability, and adjustable polarity—render them particularly advantageous for facilitating a broad spectrum of amination reactions. DESs can serve dually as reaction media and as intrinsic catalytic systems, accelerating reaction kinetics without necessitating supplementary catalysts or severe reaction conditions. They are especially efficacious in processes such as reductive amination, transamination, and multicomponent transformations, often affording superior yields and streamlining product isolation. The extensive hydrogen-bonding network intrinsic to DESs is believed to mediate crucial mechanistic steps, frequently obviating the requirement for external additives. Moreover, DESs are recyclable and exhibit compatibility with a diverse array of substrates, encompassing bio-derived and pharmaceutical intermediates. Full article
(This article belongs to the Special Issue Feature Papers in Catalysis for Pharmaceuticals)
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50 pages, 4165 KiB  
Review
Sustainable Insulation Technologies for Low-Carbon Buildings: From Past to Present
by Pinar Mert Cuce
Sustainability 2025, 17(11), 5176; https://doi.org/10.3390/su17115176 - 4 Jun 2025
Viewed by 1034
Abstract
Building facade insulation technologies have evolved from primitive thermal barriers to high-performance, multifunctional systems that enhance energy efficiency and indoor comfort. Historical insulation methods, such as thick masonry walls and timber-based construction, have gradually been replaced by advanced materials and innovative facade designs. [...] Read more.
Building facade insulation technologies have evolved from primitive thermal barriers to high-performance, multifunctional systems that enhance energy efficiency and indoor comfort. Historical insulation methods, such as thick masonry walls and timber-based construction, have gradually been replaced by advanced materials and innovative facade designs. Studies indicate that a significant proportion of a building’s heat loss occurs through its external walls and windows, highlighting the need for effective insulation strategies. The development of double-skin facades (D-SFSs), adaptive facades (AFs), and green facades has enabled substantial reductions in heating and cooling energy demands. Materials such as vacuum insulation panels (VIPs), aerogels, and phase change materials (PCMs) have demonstrated superior thermal resistance, contributing to improved thermal regulation and reduced carbon emissions. Green facades offer additional benefits by lowering surface temperatures and mitigating urban heat island effects, while D-SF configurations can reduce cooling loads by over 20% in warm climates. Despite these advancements, challenges remain regarding the initial investment costs, durability, and material sustainability. The future of facade insulation technologies is expected to focus on bio-based and recyclable insulation materials, enhanced thermal performance, and climate-responsive facade designs. This study provides a comprehensive review of historical and modern facade insulation technologies, examining their impact on energy efficiency, sustainability, and future trends in architectural design. Full article
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30 pages, 6573 KiB  
Article
Policy-Driven Dynamics in Sustainable Recycling: Evolutionary Dynamics on Multiple Networks with Case Insights from China
by Hongjuan Zhang, Haibing Liu and Rongkai Chen
Sustainability 2025, 17(11), 5132; https://doi.org/10.3390/su17115132 - 3 Jun 2025
Cited by 1 | Viewed by 505
Abstract
Residents have substantial control over their daily lifestyles, and their behavior change has a considerable potential to reduce emissions. Understanding the adoption of sustainable lifestyles and recycling behaviors and how behavioral policies might shape this decision-making is critical to the transition to sustainable [...] Read more.
Residents have substantial control over their daily lifestyles, and their behavior change has a considerable potential to reduce emissions. Understanding the adoption of sustainable lifestyles and recycling behaviors and how behavioral policies might shape this decision-making is critical to the transition to sustainable consumption patterns. This paper developed a multi-agent model on a multiplex complex network that integrates evolutionary game theory to simultaneously capture information transmission and behavioral interaction dynamics. In this model, residents determine decision utilities under the influence of internal and external factors and information transmission and then perform social interactions according to an evolutionary dynamics model. A real case of residents’ green express packaging purchase decisions in China was used for parameter initialization. Explorative simulations and scenario analyses were conducted to investigate the adoption patterns of sustainable lifestyles under different policy scenarios. Results indicate that the dynamic evolution of residents’ sustainable lifestyle decisions relies on social interactions and social networks. Government subsidies are effective in fostering sustainable decisions, but this effect is sensitive to the size of complex networks. Information campaigns and government subsidies have a significant marginal contribution to promoting sustainable lifestyles than green labeling schemes. Implementing subsidies and information campaigns as policy mixes can exert complementary effects and improve aggregate outcomes of policy packages. Full article
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18 pages, 7005 KiB  
Article
Influence of an Alkaline Activator and Mineral Admixture on the Properties of Alkali-Activated Recycled Concrete Powder-Foamed Concrete
by Yongfan Gong, Chao Liu, Zhihui Zhao, Zhengguang Wu and Bangwei Wu
Materials 2025, 18(11), 2567; https://doi.org/10.3390/ma18112567 - 30 May 2025
Viewed by 422
Abstract
Alkali-activated recycled concrete powder-foamed concrete (ARCP-FC) is a new type of insulation architectural material, which is prepared using recycled concrete powders (RCPs), slag powders, fly ash, and sodium silicate. In this study, the influence of the water-to-cement (W/C) ratio, the Na2O [...] Read more.
Alkali-activated recycled concrete powder-foamed concrete (ARCP-FC) is a new type of insulation architectural material, which is prepared using recycled concrete powders (RCPs), slag powders, fly ash, and sodium silicate. In this study, the influence of the water-to-cement (W/C) ratio, the Na2O content, and the mineral admixture content on the mechanical strength, physical properties, and thermal conductivity of ARCP-FC were investigated. The results showed that the compressive strength and dry apparent density of ARCP-FC decreased with the increase in the W/C ratio. In contrast, the water absorption rate increased as the W/C ratio increased. Fewer capillaries were formed due to the rapid setting property, and the optimal W/C ratio was 0.45. The compressive strength and dry apparent density first decreased and then increased with the increase in Na2O content. Too high Na2O addition was not conducive to the thermal insulation of ARCP-FC, and the optimal Na2O content was 6%. The compressive strength and dry shrinkage gradually decreased, while the water absorption gradually increased as the fly ash content increased. Fly ash improved deformation, and the pore was closed to the sphere, reducing the shrinkage and thermal conductivity. The optimal mixture of ARCP-FC consisted of 60% recycled concrete powders, 20% slag, and 20% fly ash. The density, porosity, compressive strength, and thermal conductivity of ARCP-FC were 800 kg/m3, 59.1%, 4.1 MPa, and 0.1036 W/(m·K), respectively. ARCP-FC solved the contradiction between compressive strength and dry apparent density, making it a promising building material for external insulation boards and insulation layers. Full article
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19 pages, 1282 KiB  
Article
Residual Performance Evaluation of Electric Vehicle Batteries: Focusing on the Analysis Results of a Social Survey of Vehicle Owners
by Hongxia Chen, Xiaoyue Liu, Jeongsoo Yu and Kazuaki Okubo
Sustainability 2025, 17(10), 4685; https://doi.org/10.3390/su17104685 - 20 May 2025
Cited by 1 | Viewed by 487
Abstract
In recent years, electric vehicles (EVs) have attracted much attention worldwide as an effective solution for realizing a carbon-neutral and decarbonized society. Since many batteries are generated over the lifespan of EVs, battery recycling has become an important issue. However, battery-manufacturing countries, including [...] Read more.
In recent years, electric vehicles (EVs) have attracted much attention worldwide as an effective solution for realizing a carbon-neutral and decarbonized society. Since many batteries are generated over the lifespan of EVs, battery recycling has become an important issue. However, battery-manufacturing countries, including China, Japan, and South Korea (CJK), have yet to build a complete battery resource recovery system. In particular, owing to the lack of a reliable battery performance evaluation method, the residual performance of a battery cannot be accurately determined. Thus, based on the results of a social survey of EV owners, the present study develops a novel battery residual performance evaluation method that can easily predict the remaining battery performance based on the usage status of the vehicle, without relying on external electronic devices to measure the battery parameters. In addition, by clarifying the human factors deteriorating vehicle battery performance and proposing sustainable utilization methods for EVs, the present study demonstrates important research prospects for the protection of the environment and progress in the automobile industry. Full article
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20 pages, 3813 KiB  
Article
Recycling Positive Electrode Materials of Li-Ion Batteries by Creating a pH Gradient Within Aqueous Sodium Chloride Electrolyser
by Yue Chen and Xiaofei Guan
Processes 2025, 13(5), 1525; https://doi.org/10.3390/pr13051525 - 15 May 2025
Viewed by 661
Abstract
Recycling the positive electrode materials of spent Li-ion batteries is critical for environmental sustainability and resource security. To facilitate the attainment of the goal, this study presents a novel approach for recovering valuable metals from positive electrode materials of spent lithium-ion batteries (LIBs) [...] Read more.
Recycling the positive electrode materials of spent Li-ion batteries is critical for environmental sustainability and resource security. To facilitate the attainment of the goal, this study presents a novel approach for recovering valuable metals from positive electrode materials of spent lithium-ion batteries (LIBs) in an H-shaped cell containing aqueous NaCl electrolyte. The process employs hydrochloric acid that could be derived from the chlorine cycle as the leaching agent. The electrolytic device is engineered to generate a high pH gradient, thereby enhancing the leaching of metal elements and eliminating the requirement for external acid or base addition. This green recycling approach adheres to the principles of a circular economy and provides an environmentally friendly solution for sustainable battery material recycling. Full article
(This article belongs to the Section Environmental and Green Processes)
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