Search Results (1,577)

Population aging and rising rehabilitation demands highlight the need for advanced assistive devices to improve mobility in individuals with motor impairments. Existing back-support lifting nursing beds often lack adequate human–machine adaptability, safety, and emotional consideration. This study presents a human-centered, data-driven optimization pipeline that integrates behavior–emotion dual recognition, simulation verification, and parameter optimization with user demand mining, biomechanical simulation, and sustainable practices. The design utilizes GreenAI, focusing on low-power algorithms and eco-friendly materials, ensuring energy-efficient AI models and reducing the environmental footprint. A dual-channel data fusion method was developed, combining movement parameters from sit-to-lie transitions with emotional needs extracted from e-commerce reviews using the Term Frequency-Inverse Document Frequency (TF-IDF) and Latent Dirichlet Allocation (LDA) models. The fuzzy Kano model prioritized design objectives, identifying multi-position adjustment, joint protection, armrest optimization, and interaction comfort as key targets. An AnyBody-based human–device model quantified muscle (erector spinae, rectus abdominis, trapezius) and hip joint loads during posture changes. Simulations verified the design’s ability to improve load distribution, reduce joint stress, and enhance comfort. The optimized nursing bed demonstrated improved adaptability across user profiles while maintaining functional reliability. This framework offers a scalable paradigm for intelligent rehabilitation equipment design, with potential extension toward AI-driven adaptive control and clinical validation. This sustainable methodology ensures that the device not only meets rehabilitation goals but also contributes to a more environmentally responsible healthcare solution, aligning with global sustainability efforts. Full article

A fully aqueous, N-methyl-2-pyrrolidone–free strategy for debundling single-walled carbon nanotubes (SWCNTs) is reported using the renewable dispersant Vanisperse^® LI. Dispersions at 2 mg mL⁻¹ were subjected to probe ultrasonication at 0.3 W mL⁻¹ and evaluated using oscillatory rheology. Complex viscosity (η*) exhibited a transient maximum (~75 min) consistent with the formation of a percolated fibrous network, followed by a decline as debundling progressed. An optimum dispersant coverage of ~1.5 mg m⁻² minimized η*, while overdosing likely induced multilayer adsorption and bridging seen by a rapid increase in η*. A two-stage centrifugation at 10,000× g yielded storage-stable suspensions of debundled SWCNTs without ultracentrifugation. SEM confirmed substantial debundling into thin fiber-like bundles. By formulating a dispersion with a dispersant that has a significantly lower cradle-to-gate carbon footprint than both fossil-based and bio-based alternatives such as CMC, this work presents a more sustainable approach to producing debundled SWCNT dispersions for advanced material applications. Full article

Railway hazardous chemical transportation, a high-risk activity that endangers personnel, infrastructure, and ecosystems, directly undermines the sustainability of the transportation system and regional development. Traditional risk management algorithms, which rely on empirical rules, result in sluggish emergency responses (with an average response time of 4.8 h), further exacerbating the environmental and economic losses caused by accidents. The standalone DBSCAN algorithm only supports static spatial clustering (with unoptimized hyperparameters); it lacks probabilistic reasoning capabilities for dynamic scenarios and thus fails to support sustainable resource allocation. To address this gap, this study develops a DBSCAN–Bayesian network fusion model that identifies risk hotspots via static spatial clustering—with ε optimized by the K-distance method and MinPts determined through cross-validation—for targeted prevention; meanwhile, the Bayesian network quantifies the dynamic relationships among “hazardous chemical properties-accident scenarios-material requirements” and integrates real-time transportation and environmental data to form a “risk positioning-demand prediction-intelligent allocation” closed loop. Experimental results show that the fusion algorithm outperforms comparative methods in sustainability-linked dimensions: ① Emergency response time is shortened to 2.3 h (a 52.1% improvement), with a 92% compliance rate in high-risk areas (e.g., water sources), thereby reducing ecological damage. ② The material satisfaction rate reaches 92.3% (a 17.6% improvement), and the neutralizer matching accuracy for corrosive leaks is increased by 26 percentage points, which cuts down resource waste and lowers carbon footprints. ③ The coverage rate of high-risk areas reaches 95.6% (a 16.4% improvement over the standalone DBSCAN algorithm), with a 27.5% reduction in dispatch costs and a drop in resource waste from 38% to 11%. This model achieves a leap from static to dynamic decision-making, providing a data-driven paradigm for the sustainable emergency management of railway hazardous chemicals. Its “spatial clustering + probabilistic reasoning” path holds universal value for risk control in complex systems, further boosting the sustainability of infrastructure. Full article

This study examines the characteristics of stretch film used to secure palletized cargo, with the aim of rationalizing its use. Growing consumption of packaging materials requires scientifically substantiated film selection that accounts for the forces ensuring cargo stability during transportation. This study used a patented mobile device to measure the static and dynamic forces generated by different types of stretch film. Experimental data revealed a linear relationship between the number of turns, the degree of pre-stretching, and the stabilizing forces, enabling optimization of wrapping parameters and a reduction in material costs. The results contribute to improved transportation safety, reduced energy consumption and carbon footprint, and lower polymer waste. This study is relevant because it develops tools for objectively assessing the effectiveness of packaging materials and for the rational selection of stretch film, thereby supporting sustainable logistics and transportation systems. Full article

Cationic polyelectrolytes, characterized by positively charged functional groups, play an essential role in industries ranging from food solutions, water treatment, medical, cosmetic, textiles and agriculture due to their electrostatic interactions, biocompatibility, and functional versatility. This paper critically examines the transition from petroleum-based synthetic polymers such as poly(diallyldimethylammonium chloride) and cationic polyacrylamides to sustainable natural alternatives derived from agri-forestry resources like starch derivatives and cellulose. Through a cradle-to-gate life cycle assessment, we highlight the superior renewability, biodegradability, and lower carbon footprint of bio-based polycations, despite challenges in agricultural sourcing and processing. This study examines cationization processes by comparing the environmental limitations of traditional chemical methods, such as significant waste production and limited scalability, with those of second-generation reactive extrusion (REX), which enables solvent-free and rapid modification. REX also allows for adjustable degrees of substitution and ensures uniform charge distribution, thereby enhancing overall functional performance. Groundbreaking research and optimization achieved through the integration of artificial intelligence and machine learning for parameter regulation and targeted mechanical energy management underscore REX’s strengths in precision engineering. By methodically addressing current limitations and articulating future advancements, this work advances sustainable innovation that contributes to a circular economy in materials science. Full article

Artificial aggregates (AAs) are man-made construction materials, and their properties greatly depend on their manufacturing process (e.g., granulation and hardening) and the raw materials used. The conducted research aimed to determine the most advantageous composition of artificial aggregates prepared based on three wastes simultaneously: municipal waste incineration ash (MWIA), sediment from the bottom of a water reservoir (SBWR), recycled cement mortar (RCM)- which was the main waste. A production process of such aggregates was also developed, with the setting of the hardening temperature (20 °C, 200 °C, 400 °C). The X-ray diffractometry (XRD), differential thermal analysis (DTA), and thermogravimetry analysis (TGA) were used to characterize the waste. Then, the properties of cementitious composites prepared with artificial aggregate with the best strength parameters of 0–100% of the natural aggregate were determined. Carbon footprint calculations were performed for the production of artificial aggregate, depending on its composition and for cementitious composites. Full article

Geopolymers, achieved through geopolymerization of aluminosilicate-containing precursors, are environmentally friendly inorganic binders with excellent mechanical strength, chemical resistance, and low carbon footprint. Beyond construction applications, geopolymers show great potential in environmental protection due to their ability to immobilize hazardous pollutants, adsorb ions and gases, and utilize industrial solid wastes. This review provides a state-of-the-art summary of recent advances in geopolymer applications in environmental fields, including (1) immobilization of hazardous wastes, (2) adsorption of hazardous ions and CO₂, and (3) resource utilization of solid wastes through geopolymerization. The mechanisms underlying immobilization and adsorption are discussed, and research gaps and future directions will be highlighted to guide further development of geopolymer-based environmental materials or application of geopolymerization in solid waste utilization. Full article

This study provides one of the largest samples of ceramic building materials with prints that has been analyzed. These tiles were recovered from Braga and date between the 1st and 7th centuries CE. There were 152 tiles examined with 420 prints from humans, dogs, cats, sheep, and goats. All prints were measured to provide data to estimate the morphological aspects of the animals found. The most common prints were from dogs that were small and medium in size. Only a few cat prints were present, but this helps us to understand the spread of this domesticated animal. The presence of sheep and goats suggests small settlements and farms once existed near the tilery. The human prints included both bare foot and shoe prints. The age, sex, and stature of the human prints were estimated, and indicate that women and children were present in the tile drying area. The children were 1 to 10 years of age. The stature of the adult females averaged 151.2 cm, which compares favorably with stature estimates from other areas of Portugal during the Roman period. Animal prints on CBM are commonly found but rarely published. Providing this data can aid future research on the comparability of the environment and animals around different tileries in the Roman world. Full article

The production of concrete strongly influences the environment. It is a versatile and sustainable construction material capable of creating a wide range of structures. It has always been indispensable as a material for the engineering and construction industry, including applications in hydraulic structures (e.g., dams, underwater tunnels, sluices, and other concrete structures), where mass concrete is a fundamental material in the construction industry. Developing sustainable concrete as an alternative construction material to the traditional one provides a reduction in the carbon dioxide footprint with regard to cement use and waste material disposal in landfills. This paper provides a comprehensive review of current trends and opportunities in sustainable construction using mass concrete. It underscores the importance of incorporating eco-friendly practices to mitigate environmental impact by using by-products as green materials. The review highlights how optimizing clinker content, supplementary cementitious materials (SCMs), and aggregates can improve the strength, durability, and thermal stability of mass concrete. Strategic material selection helps minimize thermal cracking, extend service life, and reduce environmental impact. Future research should focus on developing advanced mix design strategies and standardized practices for sustainable infrastructure. Full article

Mass timber construction (MTC) has emerged as a sustainable alternative to conventional building systems due to its low carbon footprint, high structural performance, and alignment with the principles of a circular economy. While the environmental and structural advantages of mass timber (MT) are well-documented, its occupational safety implications remain underexplored. This study examines how construction safety professionals in the United States perceive and experience safety in MT projects, and how these perceptions compare to those in conventional concrete and steel construction. To achieve this objective, the data were collected through a national web-based survey of OSHA-authorized construction safety trainers. Analyses were conducted to explore perceptions of occupational safety in MT projects, to compare safety perceptions between MT and conventional materials, and to identify construction hazards and challenges specific to MT construction. Results show that respondents with MT experience generally perceive MT projects as safer than concrete or steel, whereas those without experience tend to be more neutral. However, even among experienced safety professionals in MT, a gap persists between observed and perceived safety hazards. High rates of near misses and non-fatal injuries further indicate operational strain during MT erection. These findings underscore the need for specialized, data-driven safety training and planning frameworks tailored to MT’s distinct workflows. Targeted safety programs can help align perception with reality, thereby improving safety outcomes in this rapidly expanding sustainable construction sector. Full article

South Africa’s overlapping crises, namely ecological overshoot, energy insecurity, unemployment, and inequality, are not isolated challenges but systemic outcomes of a political economy dependent on growth. This article advances a degrowth by design framework that positions systems thinking as the primary driver of transformative change. By embedding Meadows’ leverage points within canonical archetypes such as Limits to Growth, Shifting the Burden, Success to the Successful, and Tragedy of the Commons the analysis demonstrates how reinforcing and balancing feedbacks perpetuate overshoot and social inequity and how targeted leverage strategies can reorient systems toward sufficiency, equity, and ecological repair. The framework integrates decolonial ethics, Ubuntu-informed relational dignity, pluriversal design perspectives, and legislative anchors such as South Africa’s Climate Change Act and Just Energy Transition. While the contribution is primarily conceptual, it is strengthened by illustrative vignettes, descriptive statistics, and the proposal of measurable indicators including material footprint per capita and energy intensity of wellbeing. Acknowledging the limitations of qualitative mapping and partial empirical application, the article outlines a research agenda centred on empirical validation, comparative municipal case studies, participatory action research, and open indicator repositories. The unique contribution lies in reframing degrowth as a diagnostic and prescriptive leverage strategy that is both contextually grounded and transferable. Rooted in South Africa yet relevant across the Global South, the degrowth compass functions as a normative and analytical benchmark to guide contested transitions toward just and ecologically restorative futures. Full article

The study investigates the potential of using Vietnam fly ash (FA) as a substitute for traditional Portland cement to reduce both the volume of landfilled waste and the carbon footprint of concrete mixtures, while maintaining adequate mechanical performance of the produced elements. Additionally, the incorporation of construction and demolition waste, recycled brick aggregate (BR), as a partial aggregate substitute was investigated to enhance the sustainability and resource efficiency of composite formulations. Five mixes, including a reference, were produced by casting and three-dimensional concrete printing (3DCP). Printability (flow table), water absorption (gravimetry and infrared thermography), and flexural/compressive behavior were assessed; printed specimens were tested parallel and perpendicular to the layer plane. Recycled additions reduced flow by 15–22%, yet all mixes remained printable. Printed specimens showed higher capillary uptake than cast ones. In flexure, modified mixtures composition exhibited 50% lower peak stress than the reference. Cast elements outperformed printed ones: the printed reference was 33% weaker than its cast counterpart, and other mixes were 10–15% lower. In compression, printed specimens loaded perpendicular to layers reached 6–7 MPa (35% below cast), whereas parallel loading yielded up to 3.5 MPa with larger scatter. The findings confirm the feasibility of utilizing secondary raw materials in 3DCP formulations to support resource efficiency and carbon footprint reduction in the construction industry. Full article

This study presents an innovative approach to the production of hydrogen from liquids following hydrothermal treatment of biowaste, offering a potential solution for renewable energy generation and waste management. By combining biological and hydrothermal processes, the efficiency of H₂ production can be significantly improved, contributing to a reduced carbon footprint and lower reliance on fossil fuels. The inoculum used was fermented sludge from a wastewater treatment plant, which had been thermally pretreated to enhance microbial activity towards hydrogen production. Kitchen waste, consisting mainly of plant-derived materials (vegetable matter), was used as a substrate. The process was conducted in batch 1-L bioreactors. The results showed that higher pretreatment temperatures (up to 180 °C) increased the hydrolysis of compounds and enhanced H₂ production. However, temperatures above 180 °C resulted in the formation of toxic compounds, such as catechol and hydroquinone, which inhibited H₂ production. The highest hydrogen production was achieved at 180 °C (approximately 66 mL H₂/g_TVSKW). The standard Gompertz model was applied to describe the process kinetics and demonstrated an excellent fit with the experimental data (R² = 0.99), confirming the model’s suitability for optimizing H₂ production. This work highlights the potential of combining hydrothermal and biological processes to contribute to the development of sustainable energy systems within the circular economy. Full article

Biodiesel is an alternative, sustainable, renewable, and environmentally friendly energy source, which has generated interest from the scientific community due to its low toxicity, rapid biodegradability, and zero carbon footprint. Biodiesel is a biofuel produced by the transesterification of triglycerides or the esterification of free fatty acids (FFA). Both reactions require catalysts with numerous active sites (basic, acidic, bifunctional, or enzymatic) for efficient biodiesel production. On the other hand, since the late 1990s, metal–organic frameworks (MOFs) have emerged as a new class of porous materials and have been successfully used in various fields due to their multiple properties. For this reason, MOFs have been used as heterogeneous catalysts or as a platform for designing active sites, thus improving stability and reusability. This literature review presents a comprehensive analysis of using MOFs as heterogeneous catalysts or supports for biodiesel production. The optimal parameters for transesterification/esterification are detailed, such as the alcohol/feedstock molar ratio, catalyst amount, reaction time and temperature, conversion percentage, biodiesel yield, fatty acid and water content, etc. Additionally, novel methodologies such as ultrasound and microwave irradiation for obtaining MOF-based catalysts are described. It is important to note that most studies have shown biodiesel yields >90% and multiple reuse cycles with minimal activity loss. The bibliographic analysis was conducted using the American Chemical Society (ACS) Scifinder^® database, the Elsevier B.V. Scopus^® database, and the Clarivate Analytics Web of Science^® database, under the institutional license of the Universidad Veracruzana. Keywords were searched for each section, generally limiting the document type to “reviews” and “journals,” and the language to English, and published between 2000 and 2025. Full article

The construction industry’s reliance on Portland cement (PC) significantly contributes to global CO₂ emissions, driving the search for sustainable binder alternatives. This study develops and evaluates novel mineral binder systems for wood wool acoustic panels with a reduced carbon footprint. Alternative binders, including calcium aluminate cement (CAC), magnesium oxychloride cement (MOC), and gypsum–cement–pozzolan (GCP) hybrids, were combined with additives such as metakaolin and liquid glass. Mechanical testing demonstrated that 20–30% metakaolin and liquid glass composites achieved flexural strengths of up to 2.65 MPa and densities above 490 kg/m³. The GCP system showed synergistic improvements in flexural and compressive strengths by nearly 50%, along with enhanced dimensional stability and water resistance. Life cycle assessment indicated substantial CO₂ emission increases, particularly for the MOC and CAC formulations, compared to conventional Portland cement-based panels. The carbon footprint of the binder system consisting of GCP is approximately 5.644 kg of CO₂ equivalent per functional unit compared to magnesium chloride binder systems, which reach up to 10.84 kg CO₂ eq., and white Portland cement systems, which are around 6.19 kg CO₂ eq. The three-component GCP binder system offers the best balance of mechanical performance and minimised environmental impact. Key raw material contributors to the ecological load are cement (various types), MgO, MgCl₂, and metakaolin, highlighting the importance of optimising binder formulations to reduce carbon emissions. The GCP system, in particular, demonstrates unprecedented synergistic improvements in flexural and compressive strengths, dimensional stability, and water resistance while minimising CO₂ emissions. Current work sets a new benchmark for sustainable building materials by offering an eco-innovative pathway towards low-carbon, high-performance wood wool acoustic panels, aligning with global decarbonisation goals. Full article