Search Results (932)

Environmental monitoring plays a key role in understanding and mitigating the effects of climate change, pollution, and resource mismanagement. The growth of printed sensor technologies offers an innovative approach to addressing these challenges due to their low cost, flexibility, and scalability. Printed sensors enable the real-time monitoring of air, water, soil, and climate, providing significant data for data-driven decision-making technologies and policy development to improve the quality of the environment. The development of new materials, such as graphene, conductive polymers, and biodegradable substrates, has significantly enhanced the environmental applications of printed sensors by improving sensitivity, enabling flexible designs, and supporting eco-friendly and disposable solutions. The development of inkjet, screen, and roll-to-roll printing technologies has also contributed to the achievement of mass production without sacrificing quality or performance. This review presents the current progress in printed sensors for environmental applications, with a focus on technological advances, challenges, applications, and future directions. Moreover, the paper also discusses the challenges that still exist due to several issues, e.g., sensitivity, stability, power supply, and environmental sustainability. Printed sensors have the potential to revolutionize ecological monitoring, as evidenced by recent innovations such as Internet of Things (IoT) integration, self-powered designs, and AI-enhanced data analytics. By addressing these issues, printed sensors can develop a better understanding of environmental systems and help promote the UN sustainable development goals. Full article

Quasi-solid aqueous zinc batteries (QSAZBs) have wide applications in the energy storage field due to their advantages of high safety, cost-effectiveness, and eco-friendliness. Despite prolific research output in the field of QSAZBs, existing reviews predominantly focus on experimental advancements, with limited synthesis of global research trends, interdisciplinary connections, or knowledge gaps. Herein, we review the research on QSAZBs via bibliometric analysis using the VOSviewer software (version 1.6.20). First, the data from qualitatively evaluated publications on QSAZBs from 2016 and 2024 are integrated. In addition, the annual trends, leading countries/regions and their international collaborations, institutional research and patent distribution, and important keyword cluster analyses in QSAZB research are evaluated. The results reveal that China dominates in terms of publication output (71.16% of total papers), and Singapore exhibits the highest citation impact (103.2 citations/paper). International collaboration networks indicate the central role of China, with strong ties to Singapore, the USA, and Australia. Keyword clustering indicates core research priorities: cathode materials (MnO₂ and V₂O₅), quasi-solid electrolyte optimization (hydrogels and graphene composites), and interfacial stability mechanisms. By mapping global trends and interdisciplinary linkages, this work provides insights to accelerate QSAZBs’ transition from laboratory breakthroughs to grid-scale and wearable applications. Full article

Paper’s inherent hydrophilicity and porosity cause inadequate barrier properties, failing under high humidity/temperature. This study successfully developed a hydrophobic nanocoating agent (xLNPs-OTS) through silanization modification using D276 (lignin nanoparticles with a diameter of 276 nm) as the substrate and OTS (octadecyltrichlorosilane) as the functionalizing agent. By applying the coating to paper surfaces followed by a hot-pressing process, the paper achieved comprehensive performance enhancements, including superior water, oil, and vapor barrier properties, thermal stability, mechanical strength, frictional resistance, and self-cleaning capabilities. The Cobb 60 value of LOTSC3.5T120t30 (the coating made from the OTS silanized lignin with the coating amount of 3.5 g/m² and a hot-pressing at 120 °C for 30 min) coated paper is as low as 3.75 g/m², and can withstand hot water at 100 °C for 60 min. The Cobb 60 value of the LOTSC20T120t30 (the coating made from the OTS silanized lignin with the coating amount of 20 g/m² and a hot-pressing at 120 °C for 30 min) coated paper is reduced to 0.9 g/m², the Kit grade is 6, and all coated papers are endowed with self-cleaning features. This study advances lignin’s high-value utilization, driving sustainable packaging and supporting eco-friendly paper material development. Full article

Xylanase is an essential industrial enzyme for degrading plant biomass, pulp and paper, textiles, bio-scouring, food, animal feed, biorefinery, chemicals, and pharmaceutical industries. Despite its significant industrial importance, the extensive application of xylanase is hampered by high production costs and concerns regarding the safety of xylanase-producing microorganisms. The utilisation of renewable polymers for enzyme production is becoming a cost-effective alternative. Among the prospective candidates, non-pathogenic lactic acid bacteria (LAB) are promising for safe and eco-friendly applications. Our investigation revealed that Pediococcus pentosaceus G4, isolated from plant sources, is a notable producer of extracellular xylanase. Improving the production of extracellular xylanase is crucial for viable industrial applications. Therefore, the current study investigated the impact of various medium components and optimised the selected medium composition for extracellular xylanase production of P. pentosaceus G4 using Plackett–Burman Design (PBD) and Central Composite Design (CCD) statistical approaches. According to BPD analysis, 8 out of the 19 investigated factors (glucose, almond shell, peanut shell, walnut shell, malt extract, xylan, urea, and magnesium sulphate) demonstrated significant positive effects on extracellular xylanase production of P. pentosaceus G4. Among them, glucose, almond shells, peanut shells, urea, and magnesium sulphate were identified as the main medium components that significantly (p < 0.05) influenced the production of extracellular xylanase of P. pentosaceus G4. The optimal concentrations of glucose, almond shells, peanut shells, urea, and magnesium sulphate, as determined via CCD, were 26.87 g/L, 16 g/L, 30 g/L, 2.85 g/L, and 0.10 g/L, respectively. The optimised concentrations resulted in extracellular xylanase activity of 2.765 U/mg, which was similar to the predicted extracellular xylanase activity of 2.737 U/mg. The CCD-optimised medium yielded a 3.13-fold enhancement in specific extracellular xylanase activity and a 7.99-fold decrease in production costs compared to the commercial de Man, Rogosa and Sharpe medium, implying that the CCD-optimised medium is a cost-effective medium for extracellular xylanase production of P. pentosaceus G4. Moreover, this study demonstrated a positive correlation between extracellular xylanase production, growth, lactic acid production and the amount of sugar utilised, implying the multifaceted interactions of the physiological variables affecting extracellular xylanase production in P. pentosaceus G4. In conclusion, statistical methods are effective in rapidly assessing and optimising the medium composition to enhance extracellular xylanase production of P. pentosaceus G4. Furthermore, the findings of this study highlighted the potential of using LAB as a cost-effective producer of extracellular xylanase enzymes using optimised renewable polymers, offering insights into the future use of LAB in producing hemicellulolytic enzymes. Full article

Data over sound (DoS) is an established technique that has experienced a resurgence in recent years, finding applications in areas such as contactless payments, device pairing, authentication, presence detection, toys, and offline data transfer. This study introduces CardiaWhisper, a system that extends the DoS concept to the medical domain by using a medical data-over-sound (MDoS) framework. CardiaWhisper integrates wearable biomedical sensors with home care systems, edge or IoT gateways, and telemedical networks or cloud platforms. Using a transmitter device, vital signs such as ECG (electrocardiogram) signals, PPG (photoplethysmogram) signals, RR (respiratory rate), and ACC (acceleration/movement) are sensed, conditioned, encoded, and acoustically transmitted to a nearby receiver—typically a smartphone, tablet, or other gadget—and can be further relayed to edge and cloud infrastructures. As a case study, this paper presents the real-time transmission and processing of ECG signals. The transmitter integrates an ECG sensing module, an encoder (either a PLL-based FM modulator chip or a microcontroller), and a sound emitter in the form of a standard piezoelectric speaker. The receiver, in the form of a mobile phone, tablet, or desktop computer, captures the acoustic signal via its built-in microphone and executes software routines to decode the data. It then enables a range of control and visualization functions for both local and remote users. Emphasis is placed on describing the system architecture and its key components, as well as the software methodologies used for signal decoding on the receiver side, where several algorithms are implemented using open-source, platform-independent technologies, such as JavaScript, HTML, and CSS. While the main focus is on the transmission of analog data, digital data transmission is also illustrated. The CardiaWhisper system is evaluated across several performance parameters, including functionality, complexity, speed, noise immunity, power consumption, range, and cost-efficiency. Quantitative measurements of the signal-to-noise ratio (SNR) were performed in various realistic indoor scenarios, including different distances, obstacles, and noise environments. Preliminary results are presented, along with a discussion of design challenges, limitations, and feasible applications. Our experience demonstrates that CardiaWhisper provides a low-power, eco-friendly alternative to traditional RF or Bluetooth-based medical wearables in various applications. Full article

Porous ceramics have been widely used in various fields. In this paper, porous ceramics with through-hole structures were prepared using a novel and eco-friendly gel casting method with carrageenan as the gelling agent. Especially, the idea of large size particle stacking is introduced into the gel casting process. By introducing large size alumina aggregates as raw materials, and small size micropowders as filling materials, micropores were directly formed after the green body was sintered. To tune the pore size, pore structure, gas permeability, the strength of the final porous ceramics, the components of the raw materials including the alumina aggregates, the filling materials, and sintering additives in the slurry were precisely designed. Porous Al₂O₃-based ceramics with high gas permeability, high flexural strength, and moderate porosity were finally obtained. Full article

Mycelium-based composites (MBCs) are an emerging category of cost-effective and environmentally sustainable materials that are attracting significant research and commercial interest across various industries, including construction, manufacturing, agriculture, and biomedicine. These materials harness the natural growth of fungi as a low-energy bio-fabrication method, converting abundant agricultural by-products and waste into sustainable alternatives to energy-intensive synthetic construction materials. Their affordability and eco-friendly characteristics make them attractive for both research and commercialisation. Currently, mycelium-based foams and sandwich composites are being actively developed for applications in construction. These materials offer exceptional thermal insulation, excellent acoustic absorption, and superior fire safety compared to conventional building materials like synthetic foams and engineered wood. As a result, MBCs show great potential for applications in thermal and acoustic insulation. However, their foam-like mechanical properties, high water absorption, and limited documentation of material properties restrict their use to non- or semi-structural roles, such as insulation, panelling, and furniture. This paper presents a comprehensive review of the fabrication process and the factors affecting the production and performance properties of MBCs. It addresses key elements such as fungal species selection, substrate choice, optimal growth conditions, dehydration methods, post-processing techniques, mechanical and physical properties, termite resistance, cost comparison, and life cycle assessment. Full article

This paper reviews the applications and performance advantages of ultra-high-performance concrete (UHPC), engineered cementitious composite (ECC), and recycled aggregate concrete (RAC) in composite flexural members. UHPC is characterized by its ultra-high strength, high toughness, excellent durability, and microcrack self-healing capability, albeit with high costs and complex production processes. ECC demonstrates superior tensile, flexural, and compressive strength and durability, yet it exhibits a lower elastic modulus and greater drying shrinkage strain. RAC, as an eco-friendly concrete, offers cost-effectiveness and environmental benefits, although it poses certain performance challenges. The focus of this review is on how to enhance the load-bearing capacity of composite beams or slabs by modifying the interface roughness, adjusting the thickness of the ECC or UHPC layer, and altering the cross-sectional form. The integration of diverse concrete materials improves the performance of beam and slab elements while managing costs. For instance, increasing the thickness of the UHPC or ECC layer typically enhances the load-bearing capacity of composite beams or plates by approximately 10% to 40%. Increasing the roughness of the interface can significantly improve the interfacial bond strength and further augment the ultimate load-bearing capacity of composite components. Moreover, the optimized design of material mix proportions and cross-sectional shapes can also contribute to enhancing the load-bearing capacity, crack resistance, and ductility of composite components. Nevertheless, challenges persist in engineering applications, such as the scarcity of long-term monitoring data on durability, fatigue performance, and creep effects. Additionally, existing design codes inadequately address the nonlinear behavior of multi-material composite structures, necessitating further refinement of design theories. Full article

Particulate matter 2.5 (PM_2.5) pollution poses severe threats to public health, ecosystems, and urban sustainability. With increasing industrialization and urban sprawl, accurate pollutant monitoring and effective mitigation of PM_2.5 have become global priorities. Recent advancements in machine learning (ML) have revolutionized PM_2.5 sensing by enabling high-accuracy predictions, and scalable solutions through data-driven approaches. Meanwhile, sustainable green technologies—such as urban greening, phytoremediation, and smart air purification systems—offer eco-friendly, long-term strategies to reduce PM_2.5 levels. This review, covering research publications from 2021 to 2025, systematically explores the integration of ML models with conventional sensor networks to enhance pollution forecasting, pollutant source attribution, and intelligent pollutant monitoring. The paper also highlights the convergence of ML and green technologies, including nature-based solutions and AI-driven environmental planning, to support comprehensive air quality management. In addition, the study critically examines integrated policy frameworks and lifecycle-based assessments that enable equitable, sector-specific mitigation strategies across industrial, transportation, energy, and urban planning domains. By bridging the gap between cutting-edge technology and sustainable practices, this study provides a comprehensive roadmap for researchers to combat PM_2.5 pollution. Full article

Power transformer insulation systems, composed of liquid and solid insulators, are continuously exposed to thermal and electrical stresses that degrade their performance over time and may lead to premature failure. Since these stresses are unavoidable during operation, selecting effective insulating materials is critical for long-term reliability. In this study, Kraft insulation paper was used as the solid insulator and impregnated with three different liquids: mineral oil and two natural esters (NE1204 and NE1215), to evaluate their stability under simultaneous thermal and electrical stress. The degradation behavior of the oil-impregnated papers was assessed using frequency-domain dielectric spectroscopy (FDS) and Fourier-transform infrared spectroscopy (FTIR), enabling early fault detection. Comparative analyses were conducted to evaluate the withstand capability of each liquid type during operation. Results revealed strong correlations between FTIR indicators (e.g., oxidation and hydroxyl group loss) and dielectric parameters (permittivity and loss factor), confirming the effectiveness of this combined diagnostic approach. Post-aging breakdown analysis showed that natural esters, particularly NE1215, offered superior preservation of insulation integrity compared to mineral oil. Differences between the two esters also highlight the role of chemical composition in insulation performance. This study reinforces the potential of natural esters as viable, eco-friendly alternatives in thermally and electrically stressed applications. Full article

Recyclable aluminum-containing industrial solid waste can be used as supplementary cementitious materials (SCMs) to replace cement (30–50%), thereby reducing CO₂ emissions during cement production and improving the mechanical properties and durability of concrete. Therefore, the use of SCMs in building materials presents significant potential. Due to the presence of the aluminum phase in the SCMs, the hydration products of cements blended with SCMs are changed. Compared to the primary hydration product of conventional cement, calcium silicate hydrate (CSH), the main hydration product of cement blended with SCMs is calcium aluminosilicate hydrate (CASH), which exhibits a more complex molecular structure. Understanding the role of Al in C-A-S-H at the atomic scale facilitates mechanistic insights and promotes the sustainable utilization of SCMs in eco-friendly construction. Molecular dynamics enables the rapid and accurate structural analysis and property prediction of materials. Therefore, this paper presents a systematic review of molecular dynamics simulations of CASH and discusses the role of Al in the molecular structure, dynamic, and mechanical behavior of CASH. It also analyzes the interfacial properties of CASH composites, the immobilization and transport of ions in CASH, and the temperature effect on the structure and properties of CASH. Finally, the challenges and perspectives for molecular dynamics simulation of CASH are presented. Full article

In this design, foam packaging for consumer products is replaced by the kraft paper cushioning system. The kraft paper is made into a cylindrical structure, with small cylindrical structures pasted to its outer walls. The cylindrical structure can withstand a high amount of stress, internally and externally. These cylindrical structures’ center points make an imaginary equilateral triangle. Therefore, the applied load is distributed equally across the cylinders and hexagonal structures. We can replace foam packaging with this kraft paper packaging. This design is expected to provide a more eco-friendly product than a normal packaging system. The interior design for the kraft paper is created as integrated cylindrical structures designed using Computer Aided Drawing (CAD). Various tests, such as on compression, impact, and vibration, were carried out. In this design, stimulation, cost comparison of the design, and manufacturing feasibility were examined. Full article

The Internet of Things (IoT) is one of the pivotal technologies driving the digital transformation of industry, business, and personal life. Along with new opportunities, the exponential growth of IoT devices also brings environmental challenges, driven by the increasing accumulation of e-waste. This paper introduces a novel, compact, cubic-shaped rectenna with a 3D-printed composite substrate featuring five identical patches. The design aims to integrate RF energy harvesting technology with eco-friendly materials, enabling its application in powering next-generation sustainable IoT systems. Due to its symmetrical design, each patch antenna achieves a bandwidth of 130 MHz within the frequency range of 2.4 GHz to 2.57 GHz, with a maximum efficiency of 60.5% and an excellent isolation of below −25 dB between adjacent patch antennas. Furthermore, measurements of the rectifier circuit indicate a maximum conversion efficiency of 33%, which is comparable to that of other rectennas made on 3D-printed substrates. The proposed visually unobtrusive design not only enhances compactness but also allows the proposed rectenna to harvest RF energy from nearly all directions. Full article

Seed germination, a pivotal stage in the plant life cycle, profoundly impacts crop growth and establishment. However, fluctuating environmental conditions like drought, salinity, severe temperatures, and heavy metal toxicity impede seed germination rates and seedling vigor. Seed priming is a pre-sowing seed treatment that involves the controlled hydration of seeds, proven to improve germination rate and stress resilience. It initiates pre-germinative metabolism, including enzyme activity, antioxidant accumulation, hormone modulation, and cellular repair, without radicle emergence. Recent advancements in seed priming, encompassing the application of nanoparticles, phytohormones, and beneficial microbes, have significantly broadened its potential. Despite its proven benefits, challenges such as reduced seed longevity post-priming and variability in species-specific responses remain. This paper revisits the principles and methodologies of seed priming, highlighting its physiological, biochemical, and molecular mechanisms that enhance germination under stress conditions. Additionally, it addresses current challenges and future research directions for optimizing seed priming as a low-cost, eco-friendly approach to improve crop establishment under adverse environments, thereby supporting resilient and sustainable agriculture. Full article

Sustainable traffic management relies on accurate traffic flow prediction to reduce congestion, fuel consumption, and emissions and minimise the external environmental impacts of traffic operations. This study contributes to this objective by developing and evaluating advanced machine learning models that leverage multisource data to predict traffic patterns more effectively, allowing for the deployment of proactive measures to prevent or reduce traffic congestion and idling times, leading to enhanced eco-friendly mobility. Specifically, this paper evaluates the impact of multisource sensor inputs and spatial detector interactions on machine learning-based traffic flow prediction. Using a dataset of 839,377 observations from 14 detector stations along Melbourne’s Eastern Freeway, Bidirectional Long Short-Term Memory (BiLSTM) models were developed to assess predictive accuracy under different input configurations. The results demonstrated that incorporating speed and occupancy inputs alongside traffic flow improves prediction accuracy by up to 16% across all detector stations. This study also investigated the role of spatial flow input interactions from upstream and downstream detectors in enhancing prediction performance. The findings confirm that including neighbouring detectors improves prediction accuracy, increasing performance from 96% to 98% for eastbound and westbound directions. These findings highlight the benefits of optimised sensor deployment, data integration, and advanced machine-learning techniques for smart and eco-friendly traffic systems. Additionally, this study provides a foundation for data-driven, adaptive traffic management strategies that contribute to sustainable road network planning, reducing vehicle idling, fuel consumption, and emissions while enhancing urban mobility and supporting sustainability goals. Furthermore, the proposed framework aligns with key United Nations Sustainable Development Goals (SDGs), particularly those promoting sustainable cities, resilient infrastructure, and climate-responsive planning. Full article