Search Results (37)

To achieve carbon neutrality in shipping and comply with the IMO’s increasingly stringent environmental regulations, the transition of small and medium-sized workboats to eco-friendly alternatives is an urgent issue. This study quantitatively compares the fuel efficiency and operational fuel cost savings of hybrid propulsion systems based on actual operational data from a buoy maintenance vessel. The methodology comprised four stages: First, measurement equipment was installed on the vessel to collect real-sea data. Second, the collected data were processed to derive specific fuel oil consumption curves and load profiles. Third, fuel consumption models for mechanical and hybrid propulsion systems were developed. The battery capacity of the hybrid models was selected based on actual operational requirements. Performance indicators and economic analyses were conducted for a comparative evaluation. Fourth, simulation results indicated that the hybrid electric system achieves 2.02% fuel savings, translating to annual fuel savings of USD 1053.24 and a corresponding 2.02% CO₂ reduction. The hybrid mechanical system yielded 0.66% savings. These improvements are attributed to a rule-based energy management strategy of operating generators at their optimal efficiency points and shutting down main engines during low-load periods. This study provides empirical evidence supporting Korea’s 2030 eco-friendly public vessel transition plan. Full article

Plastic pollution, particularly from polyethylene terephthalate (PET), poses significant environmental concerns due to ecosystem persistence and extensive packaging use. Conventional recycling methods face inefficiencies, high costs, and limited scalability, necessitating sustainable alternatives. Biodegradation via PET hydrolases offers promising eco-friendly solutions, although most natural PET-degrading enzymes are thermophilic and require energy-intensive high temperatures. In contrast, psychrophilic enzymes function efficiently at extremely low temperatures but often lack stability under moderate conditions. Therefore, this study aimed to enhance the ability of the Mors1 enzyme from Moraxella TA144 to operate effectively under mesophilic conditions, which is closer to the optimal conditions for environmental application. Three strategic hydrophobic substitutions (K93I, E221I, and R235F) were introduced in loop regions, generating the mutant variant Mors1^MUT. Comparative characterization revealed that Mors1^MUT retained 98% of its activity at pH 9 and displayed greater resilience across both acidic and alkaline conditions than did the wild-type enzyme. Thermal stability assays revealed that Mors1^MUT preserved 61% of its activity at 40 °C and 14% at 50 °C, whereas the wild-type enzyme was fully inactivated at these temperatures. The enzymatic hydrolysis of PET films significantly improved with Mors1^MUT. Gravimetric analysis revealed weight losses of 0.83% for Mors1^WT and 3.46% for Mors1^MUT after a 12-day incubation period. This corresponds to a 4.16-fold increase in hydrolysis efficiency, confirming the enhanced catalytic performance of the mutant variant. The improvement was further validated by scanning electron microscopy (SEM), atomic force microscopy (AFM), and attenuated total reflectance–Fourier transform infrared (ATR-FTIR) analysis. Optimization of the reaction parameters through response surface methodology (enzyme load, time, pH, temperature, and agitation) confirmed increased PET hydrolysis under mild mesophilic conditions. These findings establish Mors1^MUT as a robust mesophilic PETase with enhanced catalytic efficiency and thermal stability, representing a promising candidate for sustainable PET degradation under environmentally relevant conditions. Full article

Green synthesis represents a sustainable, reliable, and eco-friendly approach for producing various materials and nanomaterials, including metal and metal oxide nanoparticles. This environmentally conscious method has garnered significant attention from materials scientists. In recent years, interest in plant-mediated nanoparticle synthesis has grown markedly, owing to advantages such as enhanced product stability, low synthesis costs, and the use of non-toxic, renewable resources. This review specifically focuses on the green synthesis of metal oxide nanoparticles using plant extracts, highlighting five key oxides: TiO₂, ZnO, WO₃, CuO, and Fe₂O₃, which are prepared through various plant-based methods. The release of toxic effluents like synthetic dyes into the environment poses serious threats to aquatic ecosystems and human health. Therefore, the application of biosynthesized nanoparticles in removing such pollutants from industrial wastewater is critically examined. This paper discusses the synthesis routes, characterization techniques, green synthesis methodologies, and evaluates the photocatalytic performance and dye degradation mechanisms of these plant-derived nanoparticles. Full article

Background: Inhibiting α-glucosidase and α-amylase is a well-established strategy for managing postprandial hyperglycemia in type 2 diabetes mellitus. However, the adverse effects of current α-glucosidase inhibitors (α-GIs) underscore the need for safer alternatives. Methods: This study introduces an efficient, metal-free, and environmentally friendly protocol for the selective, high-yield synthesis of 1,2-disubstituted benzimidazoles. The reaction between o-phenylenediamine and various aromatic aldehydes proceeds smoothly in water at room temperature, using cost-effective and eco-friendly catalysts such as acetylsalicylic acid (ASA) or salicylic acid (SA). The methodology exhibits broad versatility, enabled by the use of different o-phenylenediamines and a wide range of aromatic and heteroaromatic aldehydes. Results: Selected compounds were assessed for their inhibitory activity against α-glucosidase and α-amylase. While all exhibited low α-amylase inhibition, several showed significant α-glucosidase inhibition, with compounds 8s (IC₅₀ = 0.39 ± 0.04 μM), 8k (IC₅₀ = 7.4 ± 1.6 μM) and 8r (IC₅₀ = 13.8 ± 2.7 μM) emerging as the most promising candidates. Notably, none of these compounds affected Caco-2 cell viability at concentrations up to 30 μM. Additionally, compounds 8r and 8s exhibited antioxidant properties, which may be relevant in counteracting the excessive production of free radicals associated with diabetes. Preliminary molecular docking and 500 ns molecular dynamics (MD) simulations were carried out on compounds 3k, 8i, 8k, and 8p–8s to support and interpret the experimental biological findings qualitatively. Full article

In this study, the focus is on investigating the performance of Jatropha curcas biodiesel as a potentially eco-friendly and non-edible collector for use in the flotation of low-rank coal. Due to its high cost and limited efficiency, using diesel as a collector for treating low-rank coal flotation presents several challenges. To achieve this aim, a systematic approach was adopted, employing a statistical design methodology to develop comprehensive mathematical models for combustible recovery and ash content. These models considered various parameters, including the dosage of the collector and frother, the solid percentage, and the depressant. The test results indicated that both models were statistically significant (p < 0.05). Furthermore, the findings showed that when the collector, frother, solid percent, and depressant were set at 0.5 kg/t and 2.13 kg/t, 0.26 kg/t and 0.214 kg/t, 15.00% and 14.40%, and 0.50 kg/t and 0.51, respectively, the ash content and recovery efficiency were 11.2% and 80.08%, respectively. The results also indicated that the doses of the frother and collector had a greater impact on the response variables than the other factors. In addition, verification experiments were conducted under the ideal conditions specified by the models to assess their validity and sufficiency. The SEM-EDS results confirmed that the concentration of carbon in coal cleaned with Jatropha biodiesel was higher than that cleaned with diesel oil. Furthermore, an FT-IR investigation showed that Jatropha biodiesel was more effective than diesel oil in reducing hydrophilic groups and enhancing hydrophobic groups. The hydrogen bonding between the oxygen-containing groups in Jatropha biodiesel and the surface of low-rank coal was responsible for the improvement in floatability and flotation recovery, which means Jatropha biodiesel, could be utilized as a substitute collector in the flotation of low-rank coal. Full article

Lubricating oils are utilised in equipment and machinery to reduce friction and enhance material utilisation. The utilisation of oil leads to an increase in its thickness and density over time. Current methods for assessing oil life are slow, expensive, and complex, and often only applicable in laboratory settings and unsuitable for real-time or field use. This leads to unexpected equipment failures, unnecessary oil changes, and economic and environmental losses. A comprehensive review of the extant literature revealed no studies and no national or international patents on neural network algorithm-based oil life modelling and classification using green sensors. In order to address this research gap, this study, for the first time in the literature, provides a green conductivity sensor with high-accuracy prediction of oil life by integrating real-time field measurements and artificial neural networks. This design is based on analysing resistance change using a relatively low-cost, three-dimensional, eco-friendly sensor. The sensor is characterised by its simplicity, speed, precision, instantaneous measurement capability, and user-friendliness. The MLP and LVQ algorithms took as input the resistance values measured in two different oil types (diesel, bench oil) after 5–30 h of use. Depending on their degradation levels, they classified the oils as ‘diesel’ or ‘bench oil’ with 99.77% and 100% accuracy. This study encompasses a sensing system with a sensitivity of 50 µS/cm, demonstrating the proposed methodologies’ efficacy. A next-generation decision support system that will perform oil life determination in real time and with excellent efficiency has been introduced into the literature. The components of the sensor structure under scrutiny in this study are conducive to the creation of zero waste, in addition to being environmentally friendly and biocompatible. The developed three-dimensional green sensor simultaneously detects physical (resistance change) and chemical (oxidation-induced polar group formation) degradation by measuring oil conductivity and resistance changes. Measurements were conducted on simulated contaminated samples in a laboratory environment and on real diesel, gasoline, and industrial oil samples. Thanks to its simplicity, rapid applicability, and low cost, the proposed method enables real-time data collection and decision-making in industrial maintenance processes, contributing to the development of predictive maintenance strategies. It also supports environmental sustainability by preventing unnecessary oil changes and reducing waste. Full article

Modern culture, strongly influenced by the growth of sectors such as the fashion and textile industries, has generated an environmental trend that is difficult to reverse. It is estimated that between 60 and 70% of the dyes used in these sectors are synthetic, which offer great versatility, a low cost, and a broad spectrum of colors, making them indispensable in many sectors. Among these synthetic dyes, azo dyes stand out due to their excellent chromophoric properties, structural stability, and ease of synthesis. However, these compounds are considered xenobiotics with a strong recalcitrant potential. This review article comprehensively examines the biodegradation potential of azo contaminants by microorganisms, including bacteria, fungi, microalgae, and consortia, using the PRISMA 2020 methodology. In this regard, this study identified 720 peer-reviewed articles on this topic that are outstanding. The analysis of these studies focused on the effect of parameters such as pH, temperature, and exposure time, as well as the enzymatic degradation pathways associated with the degradation efficiency of these contaminants. For example, the results identified that microorganisms such as Meyerozyma guilliermondii, Trametes versicolor, Pichia kudriavzevi, Chlorella vulgaris, and Candida tropicalis possess significant potential for degrading azo dyes (up to 90%). This degradative efficiency was attributed to the high enzymatic activity that cleaves the azo bonds of these contaminants through specialized enzymes, such as azoreductases, laccases, and peroxidases. Furthermore, the results highlight synergistic effects or metabolic cooperation between species that enhance the biodegradation of these contaminants, suggesting an eco-friendly alternative for environmental remediation. 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

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

The formulation of eco-friendly coatings with protective properties against corrosion and/or mechanical degradation requires the selection of appropriate bio-based binders and functional additives. Although the concentration of additives remains limited, the replacement of fossil-based additives with bio-based additives may deliver an important contribution to improving the carbon footprint of a coating, in parallel with their influences on coating performance, lifetime, and processing. However, the role of bio-based additives in life-cycle analysis (LCA) is often neglected and minorly considered in current literature. Reasons for this include the complexity of the full system, together with a lack of data, methodological inconveniences, and appropriate design of realistic scenarios. Within this work, an approach of simplified LCA is followed by ab initio cradle-to-gate analysis of coating formulations focusing on the replacement of specific fossil additives (e.g., carbon black, silicates, and calcium carbonate) with bio-based additives (e.g., biochar, bio-based wax, recovered calcium carbonate, and nanocellulose). The different environmental impact parameters (human health, eco-toxicity, resource scarcity, and carbon footprint) for bio-based additives and coating formulations are calculated from eco-cost analysis (Idemat 2024 v2.2 database), indicating a 15 to 30% gain in carbon footprint for coatings with bio-based additives. In a particular case study for improving coating performance by substituting cellulosic additives into nanocellulose from different sources, the reduction in environmental impact parameters is positively associated with their high performance at low concentration. The need for intermediate processing of bio-based additives is a main parameter contributing to their environmental impact, but environmental benefits are abundantly compensated by their carbon storage credit and performance improvement. Full article

In recent decades, the attention of researchers has been directed towards the study of the dehydration of isopropanol (IPA) through different techniques. Besides its multiple uses in the chemical industry, IPA is also a potential bio-component in eco-friendly gasolines. Extractive distillation is a successful technique for separating IPA from a minimum boiling azeotrope with water. However, the major challenge is the production of fuel-grade IPA (minimum 99.92 mol%) with low expenses. As a consequent step in the investigation of IPA dehydration with propylene glycol as extractive solvent, the present study compares its efficiency and economic viability with two other extractive solvents, namely ethylene glycol (EG) and dimethyl sulfoxide (DMSO). A systematic and comprehensive methodology was developed to design a three-column extractive distillation (TCED) for each investigated solvent. A techno-economic assessment of all the investigated processes concluded that ethylene glycol, followed by propylene glycol, seems to be the most promising solvent in the IPA dehydration process. Further, the heat integration of hot streams (SH flowsheets) demonstrated improvements over 17% in the case of ethylene glycol solvent, around 16% in the case of propylene glycol (PG) solvent, and only 10% (in the case of DMSO solvent) reduction in utility consumption, improving the energy efficiency of TCED processes. Furthermore, SH flowsheets yield a 14% cost saving obtained in terms of total annualized cost (TAC) and, respectively, 8.69%, by comparison with TCED processes. In the case of DMSO solvent, the TAC reduction is only 3.54% due to the capital cost, which has an increase of 3% mainly due to the high solvent cost. Full article

Micro Light Emitting Diode (Micro-LED) technology, characterized by exceptional brightness, low power consumption, fast response, and long lifespan, holds significant potential for next-generation displays, yet its commercialization hinges on resolving challenges in high-density interconnect fabrication, particularly micrometer-scale bump formation. Traditional fabrication approaches such as evaporation enable precise bump control but face scalability and cost limitations, while electroplating offers lower costs and higher throughput but suffers from substrate conductivity requirements and uneven current density distributions that compromise bump-height uniformity. Emerging alternatives include electroless plating, which achieves uniform metal deposition on non-conductive substrates through autocatalytic reactions albeit with slower deposition rates; ball mounting and dip soldering, which streamline processes via automated solder jetting or alloy immersion but struggle with bump miniaturization and low yield; and photosensitive conductive polymers that simplify fabrication via photolithography-patterned composites but lack validated long-term stability. Persistent challenges in achieving micrometer-scale uniformity, thermomechanical stability, and environmental compatibility underscore the need for integrated hybrid processes, eco-friendly manufacturing protocols, and novel material innovations to enable ultra-high-resolution and flexible Micro-LED implementations. This review systematically compares conventional and emerging methodologies, identifies critical technological bottlenecks, and proposes strategic guidelines for industrial-scale production of high-density Micro-LED displays. Full article

Cellulolytic and ligninolytic enzymes play a vital role in biomass valorization as they can hydrolyze cellulose, hemicellulose, and lignin, enabling eco-friendly carbohydrate utilization. This study aimed to analyze research on the production of cellulolytic and ligninolytic enzymes using fungal strains. In this review, scientific articles were searched using keywords related to cellulolytic and ligninolytic enzymes and the utilization of agro-industrial waste. Priority was given to information from peer-reviewed articles published between 2020 and 2024. The primary findings highlight the high costs associated with enzyme production, which can be partly reduced by employing low-cost carbon sources like lignocellulosic biomass. Optimization processes were also identified as critical to enhancing efficiency by reducing fermentation times, lowering energy demands for temperature control, and minimizing the use of salts or other additives in the culture medium. Researchers have approached these optimizations using traditional one-factor-at-a-time methods and statistical tools such as response surface methodologies, suggesting practical routes to improve process sustainability. Full article

The present work describes, for the first time, an eco-friendly capillary zone electrophoresis (CZE) methodology for determining apixaban (APX), an oral anticoagulant. Separation was carried out using a fused silica capillary with an applied voltage of 20 kV and hydrodynamic injection for 5 s at 50 mbar. The electrolyte system consisted of 50 mM sodium borate at pH 8.0. The method was validated as recommended by ICH, establishing selectivity, linearity, precision, accuracy, and robustness. The analytical procedure was linear in the range of 10–125 µg mL⁻¹ (r = 0.999). The limits of detection and quantification were determined to be 1.77 µg mL⁻¹ and 5.37 µg mL⁻¹, respectively. Precision was evaluated by relative standard deviation (RSD), with an intra-day RSD (n = 6) of 0.96% and an inter-day RSD (n = 18) of 4.42%. The average recovery rates for the pharmaceutical samples were excellent, ranging from 98.03% to 101.01%, with an RSD of 1.51%. Moreover, the green profile of the method was evaluated using the National Environmental Methods Index (NEMI), Analytical Eco-Scale, Green Analytical Procedure Index (GAPI), and Analytical GREEnness Metric (AGREE) assessment tools. The results suggest that the CZE method aligns with the principles of green chemistry, offering a greener alternative for the routine analysis of APX quality control. Also, the method presents a low-cost analysis, using fewer organic solvents and minimizing waste generation compared to techniques commonly used in routine analysis. Full article

Printed batteries are increasingly being investigated for feeding small, wearable devices more and more involved in our daily lives, promoting the study of printing technologies. Among these, gravure is very attractive as a low-cost and low-waste production method for functional layers in different fields, such as energy, sensors, and biomedical, because it is easy to scale up industrially. Thanks to our research, the feasibility of gravure printing was recently proved for rechargeable lithium-ion batteries (LiBs) manufacturing. Such studies allowed the production of high-quality electrodes involving different active materials with high stability, reproducibility, and good performance. Going beyond lithium-based storage devices, our attention was devoted on the possibility of employing highly sustainable gravure printing for sodium-ion batteries (NaBs) manufacturing, following the trendy interest in sodium, which is more abundant, economical, and ecofriendly than lithium. Here a study on gravure printed anodes for sodium-ion batteries based on hard carbon as an active material is presented and discussed. Thanks to our methodology centered on the capillary number, a high printing quality anodic layer was produced providing typical electrochemical behavior and good performance. Such results are very innovative and relevant in the field of sodium-ion batteries and further demonstrate the high potential of gravure in printed battery manufacturing. Full article