Search Results (19,660)

Bio-based phenolic resins were developed with phenol substitution levels of 20% and 40% with crude extracts obtained from spent coffee grounds. The experimental resins were characterized in terms of their physical, chemical and bonding properties and exhibited the typical property levels of Phenol-Formaldehyde-type resins. Plywood panels were produced bonded with the novel experimental resins, exhibiting satisfactory performance, comparable to the reference panels in terms of both shear strength and wood failure, based on the requirements of the European standards. The results demonstrate the potential of using biomass-derived compounds as substitutes for petrochemical phenol in the production of wood adhesives, thereby increasing the bio-based content of the wood panel composites produced with them and improving their sustainability. Full article

Biomineralized self-healing concrete is a type of concrete that, during its service life, induces the generation of calcium carbonate through the participation of microorganisms or active enzymes, thereby achieving self-repair of cracks at different times. Self-healing concrete based on biomineralization can achieve sustainable crack repair and could enhance the strength and extend the service life of buildings. This article comprehensively analyzes the latest progress in bio-self-healing concrete, including microbial-based self-healing, enzyme-induced calcium carbonate precipitation (EICP), microcapsule-loaded microbial in situ remediation, and bio-inorganic mineral synergist self-healing technology. The maximum repairable width of the crack is 2.0 mm, and concrete strength can be increased by 135%. These methods offer new insights and strategies for the repair of concrete cracks, providing fundamental knowledge for the later application of intelligent engineering of bio-self-healing concrete and the analysis of micro-interface mechanisms. At the same time, they clarify the practical possibility of microbial technology in building materials science and engineering and offer key theoretical support for the long-term development of China’s construction industry. Full article

Anodic aluminum oxide (AAO) is a well-known nanomaterial template formed under specific electrochemical conditions. By adjusting voltage, temperature, electrolyte type, and concentration, various microstructural modifications of AAO can be achieved within its hexagonally arranged pore array. To enable broader applications or enhance performance, post-treatment is often employed to further modify its nanostructure after anodization. Among these post-treatment techniques, AAO membrane detachment methods have been widely studied and can be categorized into traditional etching methods, voltage reduction methods, reverse bias voltage detachment methods, pulse voltage detachment methods, and further anodization techniques. Among various delamination processes, the mechanism is highly related to the selectivity of wet etching, as well as the Joule heating and stress generated during the process. Each of these detachment methods has its own advantages and drawbacks, including processing time, complexity, film integrity, and the toxicity of the solutions used. Consequently, researchers have devoted significant effort to optimizing and improving these techniques. Furthermore, through-hole AAO membranes have been applied in various fields, such as humidity sensors, nanomaterial synthesis, filtration, surface-enhanced Raman scattering (SERS), and tribo-electrical nano-generators (TENG). In particular, the rough and porous structures formed at the bottom of AAO films significantly enhance sensor performance. Depending on specific application requirements, selecting or refining the appropriate processing method is crucial to achieving optimal results. As a versatile nanomaterial template, AAO itself is expected to play a key role in future advancements in environmental safety, bio-applications, energy technologies, and food safety. Full article

Fermentation possesses intriguing and promising potential as a bioprocess for enhancing and/or transforming bioactive compounds derived from agricultural processing by-products. This study aimed to enhance the phenolic compounds and antioxidant properties of coffee cherry husks through the sustainable methodology of solid-state fermentation (SSF) using various Trichoderma fungi, specifically Trichoderma asperellum CB-Pin-01 and two Trichoderma isolates (NTY211 and PSUT001). The coffee cherry husks underwent fermentation at a controlled temperature of 28 ± 1 °C over a duration of 7 days. Both fermented and unfermented extracts, prepared using different solvents (water, ethanol, and acetone), were systematically evaluated concerning total phenolic content (TPC), total flavonoid content (TFC), and antioxidant capacities measured via DPPH and ABTS radical scavenging assays, as well as ferric reducing antioxidant power (FRAP). The findings indicated that SSF involving Trichoderma fungi significantly augmented the phenolic content and antioxidant activities in comparison to the unfermented samples (p < 0.05). Notably, the acetonic extract obtained from fermentation with the isolate NTY211 exhibited the highest contents of phenolic (191.48 ± 3.94 mg GAE/g extract) and flavonoid (106.61 ± 3.09 mg QE/g extract). The identification of phenolic compounds by UHPLC-QqQ-MS/MS analysis revealed a predominant increase in chlorogenic acid and quercetin through SSF. Consequently, SSF utilizing Trichoderma fungi may represent a viable strategy for enhancing the value of coffee cherry husks, rendering them into bioactive ingredients with potential applications in the cosmetic and food industries. Full article

This work investigates the effect of a bio-based plasticizer derived from used sunflower oil on the crystallization behavior of poly (lactic acid) (PLA), comparing it with that of the conventional plasticizer tributyrin. This study aims to explore biodegradable alternatives to petroleum-based materials and to evaluate their potential in modulating PLA crystallization kinetics without altering the crystalline structure of the resulting sustainable material solutions with tailored performance. PLA-based films containing 5%, 10%, and 15% plasticizer were prepared and characterized by differential scanning calorimetry (DSC), polarized optical microscopy (POM), and X-Ray diffraction (XRD). DSC analysis showed a decrease in the glass transition temperatures upon plasticization, with tributyrin producing a more pronounced effect than the recycled sunflower oil plasticizer. XRD patterns confirmed that the crystalline form of PLA remained unchanged regardless of plasticizer type or content. POM revealed that both plasticizers influenced crystallization kinetics, with the bio-plasticizer promoting larger and more sparsely distributed spherulites than tributyrin, indicating differences in nucleation efficiency and crystal growth. Crystallization kinetics were further analyzed using the Avrami model, the Lauritzen-Hoffman theory, and the isoconversional method. Avrami analysis indicated that nucleation mechanisms were largely unaffected, although the overall crystallization rate increased upon plasticization. Lauritzen-Hoffman analysis confirmed crystallization in Regime III, controlled by nucleation, while isoconversional analysis showed reduced activation energy in plasticized PLA. These findings highlight the ability of bio-derived plasticizers to modulate PLA crystallization, promoting the valorization of a food industry residue as a sustainable plasticizer. This study hopes to contribute relevant knowledge to emerging areas of polymer processing, such as 3D printing, to develop sustainable and high-performance PLA-based materials. Full article

Methane is a potent greenhouse gas that requires its emissions to be mitigated. A significant source for methane emissions is in the form of the biogas that is produced from anaerobic digestion in wastewater reclamation and landfill facilities. Biogas has a high valorization potential in the form of its bioconversion into ectoines, an active ingredient in skin care products, by halotolerant alkaliphilic methanotrophs. Cultures of Methylotuvimicrobium alcaliphilum 20Z were grown in bench scale stirred-tank reactors to determine factors to improve methane uptake and removal. Tangential flow filtration was also implemented for a bio-milking method to recover ectoine from culture media. Methane uptake and reactor productivity increased, with a temperature of 28 °C compared with 21 °C. Decreasing the methane gas bubble diameter by decreasing the sparger pore size from 1 mm to 0.5 µm significantly improved methane removal and reactor productivity by increasing mass transfer. Premixing methane and air before sparging into the reactor saw a higher removal of methane, while sparging methane and air separately created an increase in reactor productivity. Maximum methane removal efficiency was observed to be 70.56% ± 0.54 which translated to a CH₄-EC of 93.82 ± 3.36 g CH₄ m⁻³ h⁻¹. Maximum ectoine yields was observed to be 0.579 mg ectoine L⁻¹ h⁻¹. Full article

Biocatalysis is fundamental to biological processes and sustainable chemical productions. Over time, the biocatalysis strategy has been widely researched. Initially, biomanufacturing and catalysis of high-value chemicals were carried out through direct immobilization and application of biocatalysts, including natural enzymes and living cells. With the evolution of green chemistry and environmental concern, hybrid photoelectro-biocatalysis (HPEB) platforms are seen as a new approach to enhance biocatalysis. This strategy greatly expands the domain of natural biocatalysis, especially for bio-based components. The selective valorization of renewable furan derivatives, such as 5-hydroxymethylfurfural (HMF) and furfural, is central to advancing biomass-based chemical production. Biocatalysis offers high chemo-, regio-, and stereo-selectivity under mild conditions compared with traditional chemical catalysis, yet it is often constrained by the costly and inefficient regeneration of redox cofactors like NAD(P)H. Photoelectrocatalysis provides a sustainable means to supply reducing equivalents using solar or electrical energy. In recent years, hybrid systems that integrate biocatalysis with photoelectrocatalysis have emerged as a promising strategy to overcome this limitation. This review focuses on recent advances in such systems, where photoelectrochemical platforms enable in situ cofactor regeneration to drive enzymatic transformations of furan-based substrates. We critically analyze representative coupling strategies, materials and device configurations, and reaction engineering approaches. Finally, we outline future directions for developing efficient, robust, and industrially viable hybrid catalytic platforms for green biomass valorization. Full article

The aim of this work is to present a technologically feasible method for processing biomass into synthesis gas or hydrogen-rich gas. Three types of biomass with different lignin contents were pyrolyzed in a pyrolysis unit under well-defined conditions (ambient pressure, heating rate of 10 K min⁻¹, end temperature of 500 °C, operating particle size, variable catalyst mass) in the presence of a ruthenium catalyst (Ru/Al₂O₃, powder), and the effect of catalyst amount on the yield and gas composition was observed. Feedstock mass was always 50 g, and catalyst mass was 2.5, 5, and 10 g (mixing ratios 0.05, 0.1, and 0.2, resp.). During pyrolysis, the raw gas and vapors was passed through the catalyst bed and converted to the resulting gas and bio-oil. The gas obtained was cleaned by sequestration with CO₂ using commercial active carbon to obtain syngas with different H₂/CO ratios or hydrogen-rich gas. It was found that, depending on the catalyst amount, slow pyrolysis catalyzed by ruthenium yielded syngas with a H₂/CO ratio of approximately 0.5–5, which is further usable. The by-products obtained (bio-oil and biochar) are also described. Bio-oils from all three biomass types contained mainly carboxylic acids (33–46 wt.%) and phenols (18–33 wt.%), hydroquinone (up to 5 wt.%), and a high amount of stearate (up to 26 wt.%). All of these compounds have high utility value. The resulting biochar can probably be applied, after activation using CO₂, as a sorbent. In conclusion, under energy-efficient conditions (end temperature max. 500 °C), Ru/Al₂O₃-catalyzed pyrolysis of biomass provides syngas or hydrogen-rich gas and usable by-products. It should be emphasized that the maximum theoretical H₂ production from biomass is 60–70 g H₂/kg biomass. This limit value could negatively affect the technological development of the process. Full article

The design of sustainable nanomaterials for catalysis is a key challenge in green chemistry. Herein, we report the synthesis of halloysite nanotube (Hal)-based nanomaterials selectively functionalized with a bio-inspired polydopamine (PDA) coating, which enables the controlled anchoring of palladium and copper nanoparticles (PdNPs and CuNPs). This mild and ecofriendly strategy yields highly dispersed and ultrasmall (<5 nm) metal nanoparticles without the need for surfactants or harsh reagents. The resulting materials, Hal@PDA/PdNPs and Hal@PDA/CuNPs, were evaluated in two well-established model reactions commonly employed to probe catalytic performance: cinnamaldehyde hydrogenation and 4-nitrophenol reduction. Hal@PDA/PdNPs displayed complete conversion and >90% selectivity toward hydrocinnamaldehyde at low Pd loading (0.8 wt%) and maintained its efficiency over six catalytic cycles (TOF up to 0.1 s⁻¹), while Hal@PDA/CuNPs retained high activity through eight consecutive runs in the reduction of 4-nitrophenol. Hal@PDA/CuNPs proved to be an excellent recyclable catalyst for the reduction of 4-nitrophenol, retaining high activity through eight consecutive runs. Overall, this study introduces a robust and modular approach to fabricating halloysite-based nanocatalysts, demonstrating their potential as green platforms for metal nanoparticle-mediated transformation. Full article

Cell population and vascular vessel distribution analysis in membrane-based scaffolds for tissue engineering is crucial. Biomimetic nanostructured membranes of methyl methacrylate/hydroxyethyl methacrylate and methyl acrylate/hydroxyethyl acrylate (MMA)1-co-(HEMA)1/(MA)3-co-(HEA)2 loaded with 5% wt SiO2-nanoparticles (Si-M) were doped with zinc (Zn-M) or doxycycline (Dox-M). Critical bone defects were effectuated on six New Zealand-bred rabbit skulls and then they were covered with the membrane-based scaffolds. After six weeks, bone cell population in terms of osteoblasts, osteoclasts, osteocytes, fibroblasts, and M1 and M2 macrophages and vasculature was determined. The areas of interest were the space above (over) and below (under) the membrane, apart from the interior (inner) compartment. All membranes showed that vasculature and most cell types were more abundant under the membrane than in the inner or above regions. Quantitatively, osteoblast density increased by approximately 35% in Zn-M and 25% in Si-M compared with Dox-M. Osteoclast counts decreased by about 78% in Dox-M, indicating strong inhibition of bone resorption. Vascular structures were nearly twofold more frequent under the membranes, particularly in Si-M, while fibroblast presence remained moderate and evenly distributed. The M1/M2 macrophage ratio was higher in Zn-M, reflecting a transient pro-inflammatory state, whereas Dox-M favored an anti-inflammatory, pro-regenerative profile. These results indicate that the biomimetic electrospun membranes functioned as architectural templates that provided favorable microenvironments for cell colonization, angiogenesis, and early bone regeneration in a preclinical in vivo model. Zn-M membranes appear suitable for early osteogenic stimulation, while Dox-M membranes may be advantageous in clinical contexts requiring modulation of inflammation and osteoclastic activity. Full article

Hybrid natural/synthetic fiber laminates were examined as a practical process to cut mass, reduce material footprint, and meet structural demands while addressing sustainability targets. Yet direct, like-for-like comparisons generated under a single process and accompanied by durability measurements were limited, leaving design choices uncertain. This study aimed to fabricate and benchmark five representative laminates—C1: flax/epoxy, C2: jute/glass/epoxy, C3: hemp/carbon/epoxy, C4: flax/glass/bio-epoxy, and C5: kenaf/basalt/polyester—under a controlled hot-press schedule with a fixed cavity and verified fiber volume fraction. Panels were characterized using ASTM D3039 tension, ASTM D790 flexure, instrumented impact, 168 h water immersion, and thermogravimetric mass retention. The results were normalized to enable direct multi-criteria comparison, and a model was calibrated to predict tensile strength. C3 delivered the highest strengths (tension ≈ 120 MPa; flexure ≈ 126 MPa), while C5 showed the greatest impact capacity (≈60 kJ/m²). End-of-test water uptake at 168 h was C1 ≈ 3.4%, C2 ≈ 2.6%, C3 ≈ 1.4%, C4 ≈ 2.1%, and C5 ≈ 2.3%. The tensile predictor was fitted to panel means, with an R² of 0.988, and maintained an R² of 0.96 under leave-one-configuration-out testing. These results indicated that carbon-containing hybrids played the most critical roles in terms of stiffness, with kenaf/basalt being most suitable for stiffness-critical components at a similar density, and flax/glass with a bio-resin maximized the sustainability score while maintaining adequate strength. Future research should focus on enhancing specific strength at high renewable content through interface treatments, and extended modeling to improve flexure and impact responses. Full article

Under the tightening carbon reduction policies, port microgrids face the challenge of optimizing the installed capacity of multiple power generation types to reduce operating costs and increase renewable energy penetration. We develop a bi-level cost-optimization framework in which the upper level decides long-term capacities (PV, wind, gas turbine, bio-fuel unit, and battery energy storage), and the lower level dispatches a multi-energy port microgrid (electricity–heat–cold) on an hourly basis with frequency regulation services. To ensure rigor and reproducibility, we (i) move the methodology upfront and formalize all constraints, (ii) provide a dedicated data–preprocessing pipeline for multi-region 50/60 Hz frequency time series, and (iii) map a policy intensity index to a carbon price and/or an annual cap used in the objective/constraints. The bi-level MILP is solved by a column-and-constraint generation algorithm with optimality gap control. We report quantitative metrics—annualized total cost, CO₂ emissions (t), renewable shares (%), and regulation cycles—across scenarios. Results show consistent cost–carbon trade-offs and robust capacity shifts toward storage and biofuel as policy tightens. All inputs and scripts are organized for exact replication. Full article

Ectropis grisescens Warren (Lepidoptera: Geometridae) is a destructive pest that has severely impacted major tea-growing regions in recent years; as such, it is vital to determine how climate change influences its areas of distribution. In this study, we employed a parameter-optimized maximum entropy (MaxEnt) model, integrating 170 E. grisescens occurrence records and seven selected environmental variables, to predict the pest’s current and future potential distribution in China. Parameter optimization was conducted with the ENMeval package in R, identifying the optimal feature combination as “linear—L, quadratic—Q” and the regularization multiplier as 0.5. These results indicated that the mean diurnal range (bio2), precipitation of driest month (bio14), and elevation were the key variables contributing to the suitable area for E. grisescens. Currently, the total potential suitable area for E. grisescens in China spans approximately 1.969 × 10⁶ km², covering 20.51% of the country's land area, of which 5.121 × 10⁵ km², 7.385 × 10⁵ km², and 7.185 × 10⁵ km² possess low, medium, and high suitability, respectively. Notably, the high-suitability regions are predominantly concentrated in southeastern China, encompassing the provinces and municipalities of Zhejiang, Anhui, Hunan, Jiangsu, Chongqing, Jiangxi, Guangxi, Hubei, and Sichuan. Under future climate scenarios, it is projected that the suitable habitats for this pest will undergo varying degrees of change. Specifically, under the SSP1-2.6 scenario, the suitable habitat area is estimated to increase by up to 12.21% by the 2070s. Under the SSP2-4.5 scenario, the centroid of the suitable habitat will be displaced northwest by up to 238.4 km by the 2030s. Our findings provide valuable insights into the future management of E. grisescens and will aid in mitigating its ecological and economic impacts. Full article

The Special Issue “Unlocking the Potential of Agri-Food Waste for Innovative Applications and Bio-Based Materials” brings together recent advances and emerging strategies for the valorization of agri-food residues. This Editorial provides an overview of the contributions included in the Special Issue, highlighting innovative approaches that convert waste streams into valuable bio-based materials, chemicals, and products. The collected works demonstrate how hydrodynamic, chemical, biological, and catalytic processes can be integrated to achieve sustainable waste management and circular resource recovery. By summarizing the main findings and perspectives, this Editorial emphasizes the growing relevance of agri-food waste valorization within the framework of the circular bioeconomy and encourages further interdisciplinary collaboration to accelerate the transition toward sustainable production systems. Full article

Energy security is a growing societal and industrial concern that leads research and development toward more sustainable options. Biogas, a bio-alternative to conventional fuels, is a product generated from the anaerobic digestion of organic matter. This source of fuel production is more environmentally friendly compared to traditional fossil fuels, leading to a lower carbon footprint, higher air quality, and the promotion of a circular economy. Impurities of raw biogas, such as carbon dioxide, hydrogen sulfide, and other trace contaminants, make biogas conditioning necessary for most applications. In addition, biogas upgrading, technologies furthering biogas purity, is an important factor in the production of biomethane, a sustainable biofuel known more commonly as renewable natural gas (RNG). Diversifying fuel sources and providing energy sustainability while mitigating negative environmental effects makes RNG an attractive alternative to conventional natural gas. This document, Part I, provides an overview of current technologies related to biogas conditioning, such as sorption, oxidation, and biological treatments aimed at the removal of a wide variety of contaminants. Processes developed for biogas upgrading are also discussed, including physical/chemical absorption, pressure swing adsorption, and membrane separation. The focus of upgrading applies approaches in meeting a higher quality biofuel by further carbon dioxide exclusion to ease pipeline transport and increase combustion efficiency. These technologies present the core foundation of processes in the production of RNG; however, all face inherent challenges that deem further research and development a requirement for global adoption. The biggest challenges are either in the cost of reaching higher purities or the inability to do so without other operations. Thus, in conjunction with this document, emerging and developing technologies are provided in a separate analysis deemed Part II. Together, these documents offer a comprehensive understanding of current practices and growing technological developments. Full article