Search Results (7,124)

Alkali-activated materials (AAMs) offer an eco-friendly alternative to traditional Portland cement, yet their rheological properties, particularly in concrete mixtures, remain largely underexplored. This study conducted rheological tests to investigate the flow properties and thixotropic behavior of alkali-activated slag (AAS) concrete with varying water-to-binder (w/b) ratios and silicate modulus (Ms). The thixotropy of AAS concrete was assessed using the thixotropic index, breakdown area, and variations in apparent viscosity under different shear rates, revealing correlations between thixotropic behaviors and rheological parameters. Mixtures with lower Ms and w/b ratios showed limited slump values and rapid structural build-up due to increased interparticle connections. As Ms increased, enhanced thixotropic behaviors were observed, attributed to the rapid formation of early hydration products. This led to a significant increase in peak torque values and a slight decrease in equilibrium torque values at various rotational speeds. In turn, AAS concrete with higher Ms demonstrated improved fluidity and workability retention after thixotropic build-up was erased. The results of this study provide valuable insights into the flow and thixotropic behaviors of fresh AAS concretes for practical applications. Full article

In our investigation, we unveil a novel, eco-friendly, and cost-effective method for crafting a bio-derived electrode using discarded cotton fabric via a carbonization procedure, marking its inaugural application in a vanadium redox flow battery (VRFB). Our findings showcase the superior reaction surface area, heightened carbon content, and enhanced catalytic prowess for vanadium reactions exhibited by this carbonized waste cloth (CWC) electrode compared to commercially treated graphite felt (TT-GF). Therefore, the VRFB system equipped with these custom electrodes surpasses its treated graphite felt counterpart (61% at an equivalent current) and achieves an impressive voltage efficiency of 70% at a current density of 100 mA cm⁻². Notably, energy efficiency sees a notable uptick from 58% to 67% under the same current density conditions. These compelling outcomes underscore the immense potential of the carbonized waste cotton cloth electrode for widespread integration in VRFB installations at scale. Full article

The present paper studies the changes that occurred in the clothing trade during the COVID-19 pandemic and the influences exerted on business management. The pandemic sped up digitalization, pushing companies to quickly adapt to new economic conditions and marking a turning point for online commerce. In the fashion sector, where consumer behavior has shifted rapidly and digital technologies have transformed the business landscape, it is essential to examine these changes and their long-term impact. The research methodology involved an online questionnaire-based survey, targeting 153 respondents from various age groups. Descriptive statistics were used, such as the analysis of variation indicators, to explore patterns in the data and provide a clearer understanding of the phenomena studied. Additionally, a series of statistical tests were applied to validate the research questions. The aim was not to predict future behavior but to explain current trends and shifts, particularly the acceleration of digitalization during the pandemic. The findings highlight changes in customer behavior, the need for investments in technology and innovation, and the importance of adaptability, especially in marketing. There is a statistically significant relationship between income levels and spending on clothing, with higher incomes leading to increased expenditure. The pandemic amplified the role of online channels, particularly among higher-income groups. Promotional campaigns significantly impact purchase decisions, especially for lower-income consumers, serving as both purchase drivers and tools for customer retention. The shift toward online shopping, accelerated by the pandemic, highlights substantial growth potential for e-commerce in the fashion sector. Consumers favor platforms offering convenience, product diversity, and personalized experiences. A moderate interest in sustainable fashion was observed, with preferences leaning toward affordable and durable materials, underscoring the need for transparent and eco-friendly business practices. Full article

This study aimed to address stalk rot in sweet waxy corn while simultaneously decreasing the chemical fertilizer usage without affecting the crop yield. The investigators implemented an innovative approach that integrated disease management with environmentally sustainable agricultural practices by developing an enhanced microbial vetch fertilizer (MVF). This novel fertilizer was produced through the fermentation of vetch (Vicia villosa var. glabrescens) straw utilizing beneficial strains of Trichoderma and Bacillus species. In vitro experiments demonstrated that the antifungal microbial strains effectively inhibited Fusarium graminearum growth by 46.9% to 64.0%. Subsequent pot trials revealed that MVF application significantly reduced the incidence of stalk rot, resulting in a disease index of 21.2, which was equivalent to control efficacy of 60.2%. Field experiments further demonstrated that applying MVF at 5250 kg·ha⁻¹ produced optimal ear and grain weights, with the peak grain yield reaching 11,259.7 kg·ha⁻¹ when combined with 90% of the standard chemical fertilizer regime. This study contributes to the advancement of environmentally sustainable agricultural practices by effectively managing corn stalk rot and improving productivity by using eco-friendly techniques. The MVF shows potential as a biological alternative to boost sweet corn yields and enhance the protective enzyme activity. This study advances the field of sustainable agriculture by introducing eco-friendly techniques that effectively combat corn stalk rot and enhance crop yields. Full article

Hemp fibers, recognized for their breathability, specific strength, and ultraviolet resistance, are widely utilized in textile manufacturing and composite materials. Bio-degumming is a promising alternative technology to traditional chemical degumming that can be used to produce hemp fibers due to its eco-friendly nature. However, its lower efficiency has hindered its widespread adoption. The unclear and complex structure of the gums leads to a poor understanding on the enzyme types required for bio-degumming, thereby restricting improvements in its efficiency. In this study, the morphological characteristics, polysaccharide composition, and branched structure of hemp stem, roving fibers, and refined fibers were investigated using scanning electron microscopy and laser scanning confocal microscopy in combination with immunofluorescence techniques, with a view to identify the enzymes necessary for the efficient bio-degumming of hemp. The results revealed that the gums were primarily located in the middle lamella, phloem parenchyma, and certain xylem tissues. These tissues showed chunk-like, fence-like, and plate-like shapes, respectively, and tightly wrapped around the fiber bundles. In these tissues, pectin comprised low-esterified homogalacturonan, along with rhamnogalacturonan carrying galactan and arabinan branches. Xylan exhibited acetyl, arabinose, and glucuronic acid branches, while mannan displayed acetyl and galactose branches. Partial xylan and mannan were masked by pectin, and the branching structures impeded their enzymatic removal. As a consequence, the necessary enzymes and their synergistic effects for effective hemp roving degumming were elucidated. Pectin degradation was facilitated by pectate lyase and rhamnogalacturonan-degrading enzymes. Xylan and mannan were effectively removed by endo-xylanase and endo-mannanase, a process necessitating the synergistic action of branched-chain-degrading enzymes, including the esterase, α-L-arabinofuranosidase, α-galactosidase, and α-glucuronidase. This study provided practical strategies to enhance the efficiency of hemp bio-degumming. Full article

Global concerns about pollution reduction, associated with the continuous technological development of electronic equipment raises challenge for the future regarding lithium-ion batteries exploitation, use, and recovery through recycling of critical metals. Several human and environmental issues are reported, including related diseases caused by lithium waste. Lithium in Li-ion batteries can be recovered through various methods to prevent environmental contamination, and Li can be reused as a recyclable resource. Classical technologies for recovering lithium from batteries are associated with various environmental issues, so lithium recovery remains challenging. However, the emergence of membrane processes has opened new research directions in lithium recovery, offering hope for more efficient and environmentally friendly solutions. These processes can be integrated into current industrial recycling flows, having a high recovery potential and paving the way for a more sustainable future. A second method, biolexivation, is eco-friendly, but this point illustrates significant drawbacks when used on an industrial scale. We discussed toxicity induced by metals associated with Li to iron-oxidizing bacteria, which needs further study since it causes low recycling efficiency. One major environmental problem is the low efficiency of the recovery of Li from the water cycle, which affects global-scale safety. Still, electromembranes can offer promising solutions in the future, but there is needed to update regulations to actual needs for both producing and recycling LIB. Full article

The increasing environmental impacts caused by the high demand for concrete production have underscored the need for sustainable alternatives in the design of eco-concrete mixtures. Additionally, important industries, such as construction and mining, generate massive amounts of waste/by-products that could be repurposed towards sustainability. Consequently, this study investigates the valorization of copper slag (CS), a by-product of the mining industry as a supplementary cementitious material (SCM), and concrete as recycled coarse aggregate (RCA), derived from construction and demolition waste, as partial substitutes for Ordinary Portland Cement (OPC) and natural coarse aggregate (NCA), respectively. Eco-concrete mixtures were designed with varying replacement levels: 15% for CS, and 0%, 20%, 50%, and 100% for RCA. The mechanical properties (compressive, indirect tensile, and flexural strengths), permeability characteristics (porosity and capillary suction), and environmental impacts (carbon footprint) of these mixtures were evaluated. The results showed that the use of CS and of increasing proportions of RCA led to a monotonic loss in each of the concretes’ mechanical strength properties at 7, 28 and 90 days of curing. However, at extended ages (180 days of curing), the concrete mixtures with CS and only NCA presented an average compressive strength 1.2% higher than that of the reference concrete (mixture with only OPC and natural aggregate). Additionally, the concrete mixture with CS and 20% RCA achieved 3.2% and 5.8% higher average values than the reference concrete in terms of its indirect tensile strength and flexural strength, respectively. Finally, a cradle-to-gate life cycle assessment (LCA) analysis was implemented, whose results showed that the greatest effect on reducing the carbon emission impacts occurred due to the substitution of OPC with CS, which confirmed that the adequate technical performances of some of the concrete mixtures developed in this study are positively complemented with reduced environmental impacts. Moreover, this study presents a viable approach to minimizing resource consumption and waste generation, contributing to the advancement of eco-friendly construction materials, which aligns with the sustainable development goals. Full article

As a fundamental part of water management, water sampling treatments have recently been integrated into unmanned aerial vehicle (UAV) technologies and offer eco-friendly, cost-effective, and time-saving solutions while reducing the necessity for qualified staff. However, the majority of applications have been conducted with rotary-wing configurations, which lack range and sampling capacity (i.e., payload), leading scientists to search for alternative designs or special configurations to enable more comprehensive water assessments. Hence, in this paper, the conceptual design of a novel long-range and high-capacity WIGE UAV capable of autonomous water sampling is presented in detail. The design process included a vortex lattice solver for aerodynamic investigations, while analytical and empirical methods were used for weight and dimensional estimations. Since the mission involved operation inside maritime traffic, potential obstacle avoidance scenarios were discussed in terms of operational safety, and the aim was for autonomous trajectory tracking performance to be improved by means of a stochastic optimization algorithm. For this purpose, an artificial intelligence-integrated concurrent engineering approach was applied for autonomous control system design and flight altitude determination, simultaneously. During the optimization, the stability and control derivatives of the constituted longitudinal and lateral aircraft dynamic models were predicted via a trained artificial neural network (ANN). The optimization results exhibited an aerodynamic performance enhancement of 3.92%, which indicates a remarkable improvement in trajectory tracking performance for both the fly-over and maneuver obstacle avoidance modes, by 89.9% and 19.66%, respectively. Full article

Green spaces in urban areas, such as parks and gardens, provide recreational, social, and health benefits for more than half of the world’s inhabitants. Arthropods in urban vegetation may cause some disruption to humans but also provide vital ecological services such as biological control and pollination. However, little is known about the ecology of urban pests, their natural enemies, and how to manage them in an ecofriendly manner, especially in Southern Europe. In this review article, we consider the information available concerning the biological control of aphids in the urban green areas of Spain, mainly focusing on the different aphid species, their natural enemies (and how to enhance them), and the sampling methods used to study them. A wide range of aphid species is found in Spain, but only a few are responsible for the majority of damage (so-called k-aphids, most of which are holocyclic species), and these show two distinct injury profiles (short and long) that determine monitoring and control strategies. Urban aphids have numerous natural enemies, including more than 20 species of ladybeetles, as well as predatory hoverflies, midges, lacewings, bugs, and other groups. More than 40 species of aphid parasitoids and their tritrophic aphid plant associations have been reported. The availability and usefulness of commercially reared aphid natural enemies is discussed, and two methods to enhance natural enemies are described. We also review aphid sampling methods developed for urban green spaces. The studies provide basic information on the ecology of aphids to support conservation biological control as a reliable strategy in the urban green areas of Spain. Full article

An understanding of the psychosocial factors that influence an individual’s attitude towards climate change and the potential impact of these factors on sustainability could prove valuable in the development of future programmes and campaigns designed to encourage more eco-friendly behaviours. Therefore, the objective of this study was to examine the relationship between anxiety about climate change, climate change curiosity, and a number of variables pertaining to psychosocial functioning, including social orientations, preferred values, and political beliefs. This study involved a sample of 277 people (Mage = 30.10; SD age = 9.32) who completed a series of scales: The Climate Anxiety Scale, The Curiosity of Climate Changes Scale, Agency/Communion Scale, The Portrait Values Questionnaire, and The Political Beliefs Questionnaire. The regression analysis revealed that two aspects of social orientation, namely unmitigated agency and unmitigated communion, were predictive of anxiety about climate change. Conversely, curiosity about climate change was not predicted by different aspects of social orientation. The self-transcendence metacategory of values was found to positively predict climate anxiety, whereas the conservation metacategory of values predicts it negatively. Political beliefs were not found to predict fear of climate change; however, some aspects of political beliefs were predictive of interest in climate change. Furthermore, a cluster analysis identified three distinct clusters of participants, distinguished by varying scores on the climate anxiety and climate curiosity scales. These clusters were characterised as follows: Anxious (individuals with high levels of climate anxiety and high levels of climate curiosity), Curious (individuals with low levels of climate anxiety and high levels of climate curiosity) and Disinterested (individuals with low levels of climate anxiety and low levels of climate curiosity). The individuals grouped within these clusters demonstrated differences in some aspects of social orientation, preferred values, and political beliefs. Full article

The transport of oversized loads, such as wind turbine components, represents a key logistical challenge due to specific technical and regulatory requirements. The development of the renewable energy sector, particularly wind energy in Poland, has significantly increased the demand for this type of transport. The implementation of wind farm construction projects requires not only advanced technological solutions but also special attention to transport safety and the organization of logistical processes. This study employed the FMEA (Failure Mode and Effects Analysis) risk analysis method, which allows for the identification of potential defects and their causes. Data were collected through surveys, interviews with representatives of transport companies, and field observations. The research sample included 11 companies specializing in oversized transport in Poland and European countries. Based on the gathered information, 15 typical risks associated with the transport of wind turbine components were identified. The most significant risks include the possibility of road accidents and discrepancies between the actual dimensions of the cargo and the transport documentation. The results highlight the need for improvements in route planning, precise verification of cargo parameters, and better management of administrative processes related to obtaining permits. The development of the wind energy sector and dynamic investments in wind farms make the optimization of oversized transport a crucial element in supporting the execution of eco-friendly projects and sustainable development. Full article

The significant environmental impact from fashion and textile industries has spurred interest in sustainable alternatives, especially for accessories like sequins and beads, whose usage has surged post-pandemic. This study explores the potential of utilizing salmon industry waste from Chile to produce bio-sequins (BS) and guanine crystals (GC) from salmon skin. The production of BS offers a strategy to reduce reliance on non-renewable resources and support sustainable waste management, as these materials decompose naturally without harmful residues. Physicochemical and mechanical characterization of the BS by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD), and Fourier transform infrared spectroscopy (FT-IR), evaluated their feasibility for textile, design, and fashion applications. Additionally, GC were extracted from salmon scales using less hazardous solvents such as acetone, ethanol, and acetic acid, and subsequently immobilized on the BS for decorative purposes. Notably, tensile mechanical properties of the BS improved up to 75% after guanine decoration and exposure to simulated environmental factors like UV radiation. This work addresses the dual challenge of pollution and resource depletion, demonstrating that BS from salmon skin offer an eco-friendly alternative. It underscores the importance of adopting sustainable practices throughout the fashion industry’s production chain. Full article

Plastics play a crucial role in modern life, but their accumulation poses a serious threat to both the environment and human health. Due to their effects on the terrestrial and aquatic environment, it is essential to develop sustainable approaches to dispose of waste plastics. Traditional methods of plastic disposal, such as burning and landfilling, are problematic since they produce hazardous byproducts. Biodegradation is a potentially effective, eco-friendly approach which uses microbial consortia or isolated enzymes to break down plastic waste. Enzymes interact with plastic surfaces and hydrolyse the large polymer chains into smaller units. These byproducts can then be utilised as carbon sources by microbes, which are eventually converted into CO₂ and water. This review explores the principal approaches to plastic degradation, with a focus on existing and emerging polymers made to be readily biodegradable. In addition, sustainable valorisation methods for converting plastic waste into valuable byproducts are considered. The implementation of a circular plastic economy is expected to lead to further development, including scaling up of efficient plastic bio-upcycling processes, which can serve to stimulate environmental waste removal and value-added use of post-consumer plastic streams. Full article

This study explores a sustainable method for synthesizing quinazoline derivatives through visible light-driven photocatalysis using curcumin-sensitized titanium dioxide (TiO₂) nanoparticles. A one-pot, three-component reaction involving aldehydes, urea/thiourea, and dimedone was utilized to efficiently produce quinazoline compounds. The photocatalytic performance of curcumin-sensitized TiO₂ (Cur-TiO₂) was compared to pure TiO₂ (P-TiO₂), with Cur-TiO₂ showing significantly enhanced activity. Under optimized conditions—light intensity of 100 mW/cm², catalyst concentration of 1 mg/mL, and a reaction time of 40 min—a 97% product yield was achieved. The Cur-TiO₂ catalyst demonstrated excellent reusability, maintaining high efficiency over four consecutive cycles with minimal performance loss. This work underscores the potential of natural dye sensitization to extend light absorption of TiO₂ into the visible spectrum, providing an eco-friendly and cost-effective approach to sustainable organic synthesis. Full article

This study explored the effect of incorporating cellulose and starch nanoparticles, obtained from the Commelina coelestis Willd plant, on the physical and chemical properties of starch-based films derived from the same plant. Additionally, the synergistic effect of combining the nanostructures was assessed. The nanocomposite biopolymer films were prepared by the casting method using 1 and 3 wt% concentrations of the nanostructures (CNCs: cellulose nanocrystals, CNFs: cellulose nanofibers, SNCs: starch nanocrystals), or their blend. The physicochemical (swelling capacity and water solubility), morphological (SEM and AFM), thermal (DSC and TGA), and mechanical properties (tensile strength, elongation at break, and Young’s modulus) of the films were evaluated. The nanocomposite biopolymer films exhibited better dimensional stability (40–60%) than the control films. Tensile strength (8–300%) and Young’s modulus (15–690%) were improved. Moreover, these films displayed enhanced thermal stability, withstanding temperatures exceeding 305 °C. FTIR spectra evidenced intermolecular interaction among the matrix and nanostructures. Microscopic analyses further supported the integrity of the films, which displayed a homogeneous surface and the absence of fractures. In addition, the nanocomposite biopolymer films prepared with 1 wt% cellulose nanocrystals and nanofibers had a lower opacity than those with a higher percentage (3 wt%). Overall, our findings suggest that the Commelina coelestis Willd is a promising starch source that can be used to obtain nanocomposite biopolymer films as an alternative to produce novel, efficient, and eco-friendly materials with adequate thermo-mechanical properties intended to replace conventional plastic materials in single-use applications such as those used in the food packaging industry. Full article