Search Results (664)

The co-gasification of biomass and municipal solid waste (MSW) has high potential for sustainable energy generation and waste-to-energy applications. Calliandra calothyrsus (CC) and MSW pellets have complementary thermochemical properties, although there are few experimental studies on their co-gasification in downdraft reactors. This study analyzed the effect of the feedstock composition on the temperature distribution inside the reactor, the syngas composition, and the quality of syngas energy in a 1–2.5 kg/h downdraft gasifier during co-gasification. Six feedstock blend compositions were experimentally evaluated: they were 100 CC, 70 CC–30 MSW, 60 CC–40 MSW, 40 CC–60 MSW, 30 CC–70 MSW, and 100 MSW. The criteria considered for measuring include reactor temperature distribution, syngas composition (CO, H₂, CO₂, and C_nH_m), and lower heating value (LHV). The results indicated that the 70 CC–30 MSW blend had the best syngas performance with a higher oxidation-zone temperature, greater CO concentration, reasonably steady H₂ generation, lower C_nH_m concentration, and the highest syngas LHV compared to other feedstock compositions. In the gasification process, the increase in the proportion of CC was beneficial to char reactivity, oxidation–reduction reaction, and tar cracking. The increase in MSW fractions decreased syngas quality due to the increase in ash and moisture content. The results show that co-gasification of Calliandra calothyrsus and bio-dried MSW pellets can increase syngas quality and provide practical insight into the optimization of biomass–MSW blending for downdraft gasification systems. Full article

Raw lacquer, a natural polymer derived from the bast of lacquer trees (Toxicodendron vernicifluum), is renowned as the “King of Coatings” due to its exceptional film-forming properties, abrasion resistance, corrosion resistance, and biocompatibility. However, its inherent limitations—including stringent drying conditions, slow curing rates, deep coloration, and difficult application—have severely restricted its modernization and widespread adoption. This review systematically summarizes recent research advances in the modification and application of raw lacquer, focusing on four major modification strategies: (1) Nanocomposite modification—incorporating functional nanofillers such as Al₂O₃, cellulose nanofibrils (CNF), polydopamine (PDA) melanin-like nanoparticles, and SiO₂ to significantly enhance film hardness, compactness, UV-aging resistance, and drying kinetics. (2) Chemical structure modification—employing molecular design strategies including aminoanthraquinone grafting, tung oil blending, water-based emulsification, and terpene/allyl group functionalization to improve hydrophobicity, flexibility, fast-drying properties, and achieve dual photo/oxygen curing. (3) Biomass synergistic composites—utilizing natural polymers such as chitosan and lignin, along with bio-inspired adhesion mechanisms (e.g., PDA), to confer advanced functionalities including antibacterial and antifouling properties. (4) Curing behavior regulation—precisely controlling drying kinetics through inorganic salt ion microenvironment engineering, nonionic surfactants, and salicylaldehyde Schiff base-based driers. Building upon these foundations, this review further expands on the emerging high-value applications of modified lacquer in preventive conservation of cultural heritage, advanced functional coatings (anti-corrosion, super-hydrophobicity, flame retardancy), biomedical materials (hemostasis, antibacterial activity, drug-controlled release, water treatment adsorption), and intelligent responsive flexible electronics. Finally, addressing challenges including weak fundamental research, bottlenecks in green industrialization, and lack of standardization, future development directions are proposed encompassing interdisciplinary innovation, sustainable modification strategies, integration of multifunctional intelligent systems, and big data-driven research paradigms, aiming to provide theoretical guidance and technical references for the high-value utilization and modernization of lacquer resources. Full article

In this study, nine strains of plant growth-promoting rhizobacteria (PGPR) with multiple growth-promoting functions were isolated and screened from the rhizosphere of plants (Phragmites communis, Triglochin maritimum, and Alhagi maurorum) in the arid and barren regions of Western China. These strains belong to five genera: Klebsiella, Bacillus, Serratia, Pseudomonas, and Flavobacterium. The growth-promoting characteristics of these nine strains (PAP4, PA35, AC12, ACP1, AC25, TP7, TP8, TP12, and TP14) were analyzed. Furthermore, the growth-promoting potential of these PGPR strains was comprehensively evaluated through plate and pot experiments using Arabidopsis thaliana and alfalfa. The results indicate that most strains possess the ability to fix nitrogen and secrete zeatin and extracellular polysaccharides (EPS). Some strains exhibited significant traits such as phosphate solubilization, siderophore secretion, and the production of 1-aminocyclopropane-1-carboxylate (ACC) deaminase and indole-3-acetic acid (IAA). All strains showed high salt tolerance (0–8% NaCl) and were induced to secrete more EPS under salt stress. Plate experiments demonstrated that volatile organic compounds (VOCs) from the nine strains significantly promoted the root development of Arabidopsis thaliana and optimized its root architecture. Pot experiments revealed that inoculation with single strains influenced the growth of alfalfa to varying degrees; among them, strain TP14 showed the best performance, increasing plant height and shoot dry weight by 44.7% and 51.2%, respectively. Regarding microbial consortia, the combinations BD (PAP4 + TP14), ABC (PA35 + PAP4 + AC25), and ABCD (PA35 + PAP4 + AC25 + TP14) significantly improved the biomass, plant height, and stem diameter of alfalfa. The superior strains and their combinations identified in this study effectively promote plant growth. These high-performing PGPR strains provide valuable microbial resources for the development of bio-fertilizers tailored for saline–alkali and barren regions in Western China. Full article

Nanotechnology has attracted increasing attention in agricultural and environmental research, but the biological effects and potential risks of nanoparticles based on non-essential elements remain insufficiently understood. This study investigated the physiological and biochemical responses of rice (Oryza sativa L.) seedlings to yttrium oxide nanoparticles (Y₂O₃ NPs) and zirconium oxide nanoparticles (ZrO₂ NPs) at 5, 25, and 100 mg/L under hydroponic conditions. The results showed that neither Y₂O₃ nor ZrO₂ NPs significantly affected visible growth traits or SPAD-based leaf chlorophyll status, suggesting that seedling morphology and leaf greenness remained relatively stable during exposure. However, both nanoparticles induced distinct biochemical responses. Y₂O₃ NPs caused root-level stress-like responses, including increased malondialdehyde (MDA) accumulation and suppressed peroxidase (POD) and catalase (CAT) activities under specific exposure conditions. In contrast, ZrO₂ NPs were more closely associated with the activation of antioxidant defenses, particularly through enhanced POD activity and increased root CAT activity. Inductively coupled plasma mass spectrometry (ICP-MS) analysis further showed that Y and Zr were mainly retained in roots, with root Y reaching 5014.12–11,255.05 mg kg⁻¹ dry weight (DW) under Y₂O₃ NP exposure and root Zr reaching 189.68 mg kg⁻¹ DW under high-concentration ZrO₂ NP exposure. Bio-transmission electron microscopy (bio-TEM) supported the root-dominant localization of nanoparticle-associated electron-dense aggregates. These findings indicate that Y₂O₃ and ZrO₂ NPs exert material-specific effects on rice seedlings, with root accumulation and antioxidant regulation serving as more sensitive indicators than visible growth traits. However, further research is needed to clarify the long-term environmental fate of Y₂O₃ and ZrO₂ NPs and to assess their potential ecological and food safety risks in agricultural systems. Full article

Agricultural waste materials can serve as functional constituents in cement-based composites through three pathways: (i) organic bio-aggregates that lower density and alter thermal behavior, (ii) lignocellulosic fibers that control cracking and improve post-cracking resistance, and (iii) agro-ash supplementary cementitious materials (SCMs) that densify pore structure and reduce permeability when ash quality and curing are controlled. This review draws on 98 papers, with coconut shell aggregate and coir/coconut fibers as the core focus; agro-ash SCMs (notably palm oil fuel ash, POFA, and rice husk ash, RHA) enter where they clarify mechanisms or inform hybrid design. Rather than cataloging compressive-strength data, the synthesis is organized around controllable process inputs (feedstock conditioning, mix design, curing) and the interface-governed mechanisms that determine performance: interfacial transition zone (ITZ) character and pore connectivity. In coconut shell systems, density reductions come at a cost: elastic modulus drops and moisture sensitivity rises unless shell conditioning, particle packing, and matrix refinement are managed. In fiber systems, gains in toughness and residual capacity are bounded by mixing workability and by the long-term stability of the fiber–matrix bond under alkaline and wet–dry exposure. A mix must first meet strength, serviceability, and transport requirements before its embodied impact is compared with conventional alternatives. The contribution is to reframe these systems around controllable processing and interface mechanisms instead of tabulated strength values; preparation, treatment, and characterization data are consolidated into bounded design windows, an explicit core versus supporting evidence convention is applied, and sustainability is judged under functional equivalency rather than per-volume carbon. Full article

Mucic acid (MA) is used as a chelating agent or as a building block for bio-based polymers. MA can be produced by regioselective oxidation of D-galacturonic acid (GA). Gluconobacter oxydans is known for the partial oxidation of various substrates via membrane-bound dehydrogenases. As the wild-type strain shows only low oxidation activity towards GA, the engineered multideletion strain G. oxydans BP9.1 pta-mGDH, overexpressing a membrane-bound glucose dehydrogenase from Pseudomonas taetrolens, was used in buffered whole-cell batch biotransformations with GA as the sole substrate. Initial cell-specific MA formation rates elevated with rising educt concentrations up to 63 g L⁻¹. At pH 4, full GA conversion was only achieved with an initial GA concentration of 10 g L⁻¹. Complete conversion of 94 g L⁻¹ of GA was achieved at pH 5 with 3.4 g L⁻¹ of G. oxydans BP9.1 pta-mGDH within 48 h, resulting in >100 g L⁻¹ of MA, corresponding to a yield of >99% (mol/mol). Isolation of MA (purity > 90%) was achieved after cell separation, followed by cooling crystallization and drying, with a yield of 94%. Complete, full-yield GA conversion using non-growing cells of engineered G. oxydans in simple phosphate buffer yielded high product concentrations and enabled simple, high-yield product isolation, thus resulting in cost-effective and sustainable bioproduction of MA. Full article

The increasing demand for sustainable and affordable surfactants requires the exploration of novel bio-based alternatives. In this context, this work investigates the potential of baker’s yeast (Saccharomyces cerevisiae) as a surface-active agent. To this purpose, the performance of commercial dry, commercial fresh, and cultivated yeast was evaluated by characterizing their wetting behavior and formulating emulsions with a fixed oil-to-water ratio. Microscopic and macroscopic stability was monitored over 24 h and quantified via the creaming index (CI). The experimental results demonstrate that both the yeast source and concentration significantly dictate the surface properties and emulsion stability. Notably, commercial dry yeast exhibited the highest degree of hydrophobicity, likely attributed to the presence of sorbitan monostearate (SMS) in the formulation. Consequently, this was the main variant capable of producing stable emulsions, with microscopic evidence suggesting a Pickering-like stabilization mechanism driven by the irreversible adsorption of yeast cells at the oil–water interface. Conversely, commercial fresh and cultivated yeast failed to exert significant stabilizing activity. These results demonstrate that S. cerevisiae biomass can be effectively repurposed as a functional constituent in green emulsion technology, offering a scalable pathway for the development of biocompatible, particle-stabilized industrial formulations. Full article

Sustainable phosphorus (P) management in agriculture requires a circular economy approach through the use of so-called bio-based fertilizers (BBFs). The properties of BBFs vary widely depending on raw materials and production processes. However, it is still unknown how these properties, and particularly the dominant P compounds determine not only the efficiency of BBFs in supplying P to crops, but also their effects on soil functioning and crop quality. This study aimed to evaluate the efficiency of a representative set of BBFs, and relate this efficiency to their composition and dominant P compounds. To this end, 14 BBFs were studied: four from water purification (struvite, vivianite, and sewage sludge with and without composting), four composts (municipal solid waste (MSW), vineyard residues, and two using olive husks), three vermicomposts (two homemade and one commercial), fish meal, digestate, and a commercial organic fertilizer. Phosphorus forms in BBFs were determined using ³¹P nuclear magnetic resonance spectroscopy (P-NMR). The BBFs were compared to a single superphosphate (SSP) in a pot experiment growing wheat in two different alkaline soils, one rich in iron (Fe) oxides and one rich in carbonates. The effects on critical elements in grain [magnesium, Fe, zinc (Zn), manganese, and copper] and enzyme activities related to soil functioning and P cycling were also assessed. The dominant P compound in the BBFs was orthophosphate (73.8–89.5% of the total P in the NaOH–EDTA extracts). The MSW had the highest polyphosphate content (4.1%), a complex inorganic P compound. The organic P content ranged from 9.2% (fish meal) to 25.5% (Moge). Sewage sludge and composted sludge contributed high levels of phosphonates (4.1 and 5.6% of extracted P). The most abundant organic P compound class was inositol hexakisphosphates (IHPs), and myo-IHP (phytate) was the dominant IHP stereoisomer (1.2–6.4%) followed by D-chiro-IHP and scyllo-IHP. Plant dry matter and grain yield with most BBFs were not significantly different from that of SSP in both soils, likely due to the high concentrations of phosphate in relatively soluble forms in most of the BBFs. Vivianite and sewage sludge resulted in significantly higher grain yield than SSP (43% and 40%, respectively) in the carbonate-rich soil, likely due to progressive phosphate dissolution, which decreased the precipitation rate of insoluble calcium (Ca) phosphates. The highest P recoveries were obtained with horse manure vermicompost (65% and 15% higher than SSP in the Fe oxide-rich and in the carbonate-rich soil, respectively), partially attributed to the decreased precipitation rate of insoluble Ca phosphates with the added organic matter. Some BBFs increased micronutrient concentrations in grains and most decreased the P-to-Zn ratio relative to SSP. Overall, phosphatase and β-glucosidase activities increased with carbon-rich BBFs. Most of the studied BBFs could effectively replace fertilizers from non-renewable sources, in some cases with better crop P recoveries. Furthermore, some BBFs could provide additional benefits to grain quality, in terms of micronutrient supply for humans, and soil functioning. Full article

Drought stress is a major abiotic constraint limiting mung bean (Vigna radiata L.) productivity in arid and semi-arid agroecosystems. This study investigated the individual and synergistic effects of Bradyrhizobium sp. and arbuscular mycorrhizal fungi (AMF) on plant growth, nutrient acquisition, mycorrhizal colonization, and yield of mung bean under contrasting soil moisture regimes. A greenhouse pot experiment was conducted using a factorial completely randomized design with six microbial treatments (uninoculated control, Acaulospora scrobiculata, Claroideoglomus etunicatum, Bradyrhizobium sp., and their respective co-inoculations) and three field capacity levels (50, 75, and 100%). Drought stress was imposed gravimetrically 20 days after sowing. Water limitation significantly reduced growth, biomass accumulation, nutrient uptake, mycorrhizal colonization, and yield in uninoculated plants. In contrast, microbial inoculation markedly mitigated drought-induced adverse effects, with co-inoculation showing the strongest response. Plants receiving combined AMF and Bradyrhizobium inoculation exhibited significantly higher plant height, shoot and root biomass, total dry matter, nitrogen and phosphorus uptake, and yield attributes across all moisture regimes, particularly under severe drought (50% field capacity). Mycorrhizal dependency increased with increasing drought severity, highlighting a greater functional reliance on AM symbiosis under water-limited conditions. Enhanced drought tolerance was closely associated with increased root colonization and improved nutrient acquisition driven by synergistic AMF–Bradyrhizobium interactions. These findings demonstrate that tripartite symbiosis represents a sustainable bio-inoculant strategy to enhance drought resilience and productivity of mung bean under climate change-induced water stress. Full article

This study investigates the durability of silicone-based membranes in contact with hempcrete under combined moisture and temperature exposure. Membrane specimens were aged in contact with non-treated and treated hempcrete under dry and wet conditions at temperatures up to 90 °C. The evolution of chemical, thermal, and microstructural properties was characterized using FTIR, TGA, DSC, optical microscopy, and SEM–EDS analyses. Results show that dry exposure does not induce measurable changes in membrane structure or performance, confirming that temperature alone is not a critical degradation factor. In contrast, wet exposure leads to significant chemical, thermal, and microstructural changes in the membrane, including degradation of the siloxane network, reduced polymer chain mobility, and the formation of calcium-rich mineral deposits at the interface. These results indicate that membrane degradation is governed by a coupled moisture–ion mechanism involving ion transport, mineral deposition, and hydrolysis of the polymer network. Fiber treatment slightly reduces the aggressiveness of the leachate but does not prevent degradation under wet conditions. Overall, moisture availability and leachate chemistry are identified as key factors controlling the durability of silicone membranes in contact with bio-based materials. Full article

Acrylated epoxidized soybean oil (AESO) is a bio-based, biocompatible, and biodegradable photopolymerizable resin that exhibits shape-memory behavior, making it attractive for a wide range of biomaterial applications. Despite various strategies to fabricate porous AESO scaffolds for tissue regeneration, achieving high pore interconnectivity remains challenging. Herein, we demonstrate the utility and versatility of thermoreversible terpenes as porogens in AESO to enable the formation of highly aligned and interconnected pore architectures. More specifically, a blend of 90 wt% camphene and 10 wt% camphor was employed as the terpene system, since it could be completely melted at 70 °C, uniformly mixed with liquid AESO, and subsequently crystallized at −20 °C. This process generated a bicontinuous network comprising terpene crystals and liquid AESO, thereby enabling efficient UV photopolymerization of AESO. Following terpene removal via freeze-drying, highly aligned pore networks with excellent pore interconnectivity were obtained, which are hardly achievable using conventional liquid or solid porogens. The porosity and mechanical properties of the AESO scaffolds were tuned by adjusting terpene content. Porosity increased from 61.5 to 81.5% as terpene content rose from 60 to 80 vol%. As a result, tensile strength decreased from 0.29 ± 0.045 to 0.17 ± 0.017 MPa, while elongation at break increased from 20.2 ± 4.9 to 35.5 ± 1.34%. Furthermore, this approach is compatible with vat photopolymerization (VP), a 3D printing technique. As a proof of concept, dual-scale porous AESO scaffolds, composed of unidirectional channels surrounded by highly aligned porous frameworks, were successfully fabricated. These results indicate that a variety of dual-scale porous AESO scaffolds, with greatly enhanced mechanical properties at given porosities coupled with outstanding tissue regeneration, can be produced through VP using terpene porogens, in contrast to conventional porous scaffolds comprising uniform porous frameworks. Full article

Drying in granular porous media is governed by coupled thermal and hydraulic processes that can be substantially modified by biological activity. This proof-of-concept study investigated how surface heating and fungal colonization influence the evolution of thermal conductivity (λ) and matric suction (ψ) as functions of volumetric water content ${\theta }_v$ in Ottawa 20/30 sand. Four treatments were examined: sterile sand at 22 °C (T1), sterile sand at 28 °C (T2), fungal-amended sand with 10% biomass and 9-day incubation (T3), and fungal-amended sand with 15% biomass and 30-day incubation (T4). Samples were instrumented to monitor ${\theta }_v$, λ, and ψ during controlled evaporation using synchronized HYPROP and VARIOS measurements on the same specimen. Across all treatments, λ increased with ${\theta }_v$ (that is, λ declined as drying progressed), and ψ reflected the transition from hydraulically connected to disconnected pore water. Heating shortened the drying time but did not materially change the form of the λ–${\theta }_v$ relationship or generate strong matric gradients in sterile sand. Low biomass (T3) produced thermal and hydraulic responses comparable to the heated sterile control (T2), indicating limited pore-scale modification at early colonization. In contrast, high biomass (T4) widened the effective saturation range, maintained low and nearly uniform ψ across depth, and exhibited the steepest mid-range λ–${\theta }_v$ slope with a higher peak λ (~4 Wm⁻¹K⁻¹), consistent with hyphae and extracellular polymers stabilizing thin water films. A soil water retention curve (SWRC) analysis using the van Genuchten model further indicated increased water retention and delayed air entry with an increasing fungal biomass, with approximate air-entry values increasing from ~1.8 kPa (T3) to ~3.0 kPa (T4). Tests were terminated upon tensiometer cavitation rather than complete gravimetric dryness, constraining observations at very low ${\theta }_v$. These results indicate that heating primarily affects the rate of drying, whereas fungal networks alter the pathway by preserving hydraulic and thermal continuity at relatively high ${\theta }_v$. This behavior suggests a potential role of bio-mediated structuring in influencing near-surface thermo-hydraulic processes relevant to energy foundations, soil covers, and desiccation management in biologically active or bio-engineered soils. Full article

Agricultural and agro-industrial waste can be valorized through biodrying, a process that uses microbial activity to accelerate water loss to obtain a biodried material (BM) with high calorific value and potential use as a biofuel. This material has the advantage of being easily transported, stored, and preserved until later use. However, its high organic matter content allows it to be used for other purposes. In this study, the use of BM (made from orange peel, grass, mulch, pruning waste, and compost), either alone or mixed with fresh organic waste (FOW) as feed for Eisenia foetida in a vermicomposting system, was evaluated over a period of 49 days. The proportions of BM used were 100%, 75%, 50%, 25%, and 0%, with the remainder completed with FOW. During the bioprocess, temperature, moisture, and pH were monitored, and at the end of the experiment, the survival and reproduction of E. foetida as well as the quality of the humus obtained were analyzed. In the treatments containing 100% and 75% BM, worm survival was reduced by 28.5% and 7.7%, respectively, although the highest number of cocoons (28 and 24 cocoons kg_humus⁻¹) was observed in these treatments compared with all others. The humus obtained from all treatments complied with the NMX-FF-109-SCFI-2008 standard, which designates quality grades as extra, first, and second. The treatment with 100% BM produced first-quality humus, but the treatments with mixtures of BM and FOW produced extra-quality humus. The results support the diversification of BM uses and its incorporation into sustainable bioprocesses such as vermicomposting and the production of new value-added products. Full article

To promote circular economy in construction, this study evaluates the mechanical surface integrity and long-term water durability of sustainable low-density particleboards utilizing agro-forestry residues, such as corn cob, corn stalk, hemp shive and wood fibres. These are bonded using an ecological mimosa tannin adhesive in comparison to a conventional urea–formaldehyde-based adhesive. Performance was assessed through apparent density, surface cohesion, Shore A hardness and impact resistance. Furthermore, the water sensitivity was assessed through total water absorption (WA), thickness swelling (TS), and a customized cyclic immersion-drying protocol. Results showed a significant correlation between density and Shore A hardness (R² = 0.77). While hemp- and corn-based boards showed surface performance competitive with commercial standards, the wood fibre series exhibited extreme water susceptibility, with mass variations exceeding 400% during cycling. Additionally, tannin-based boards showed evidence of leaching, with an 11% mass loss after three emersion cycles. These findings conclude that while tannin adhesives are viable renewable alternatives, these bio-boards are primarily suited for interior lining in dry environments, as lightweight formulations require additional protection to ensure durability in practical building applications. Full article

Environmental concerns over plastic-based adhesives highlight the urgent need for biodegradable alternatives. This study transforms milkfish (Chanos chanos) skin waste from the fishery industry into a collagen–polyvinylpyrrolidone (PVP) biohybrid adhesive stick for paper bonding. Milkfish showed the highest adhesive strength among twenty species, requiring ≥213.7 mg/g hydroxyproline for optimal performance. Type I collagen was confirmed via Fourier transform infrared (FTIR) and amino acid composition, and the extraction yield reached 68.82%. The fish skin collagen–PVP glue stick demonstrated paper adhesion and physicochemical properties comparable to starch-based and commercial glues, with lower hardness and more dry adhesive per unit area. Sensory evaluation using quantitative descriptive analysis revealed no significant differences (p < 0.05) compared to commercial glue sticks, except for increased glue consumption and reduced shape retention. The shelf life exceeded 70 days. Collagen adhesive from fish skin offers comparable efficiency to chemical and other bio-based adhesives, providing a sustainable solution that promotes the circular economy and green innovation. Full article