Search Results (377)

The development of high-performance wood-based materials has attracted increasing interest as a means of enhancing the mechanical properties of wood for structural applications. Mechanical densification combined with chemical pretreatment is an effective approach; however, many reported methods rely on complex multi-component chemical systems or severe chemical conditions designed to dissolve lignin or hemicelluloses. In this study, a simplified NaOH-only pretreatment followed by hot-press densification was investigated, targeting selective cell-wall plasticization rather than extensive polymer dissolution. Juniper (Juniperus communis), hawthorn (Crataegus monogyna), and birch (Betula pendula) were used as samples of softwood and hardwood species. Wood specimens were pretreated in 1 M NaOH at 145 °C for 10–30 min and subsequently densified by radial compression. Changes in chemical composition were evaluated by HPLC after acid hydrolysis and FTIR spectroscopy, while microstructural changes were examined using SEM. Physical and mechanical properties were assessed through density measurements and three-point bending tests. The results show that NaOH-only pretreatment induces hemicellulose deacetylation and modification of interpolymer linkages without substantial changes in the main wood polymer contents. Densification resulted in effective lumen collapse and a compact microstructure, leading to a significant increase in density and mechanical properties. Overall, the results demonstrate that efficient wood densification and mechanical enhancement can be achieved by promoting polymer mobility through selective cleavage of interpolymer bonds, using a simplified, single-alkali pretreatment that reduces chemical complexity and material loss while avoiding extensive lignin or hemicellulose dissolution. Full article

Improper disposal of granite sawdust from stone processing and heavy metal-containing tailings sand can pose severe threats to the environment and human health. Based on their physicochemical properties, granite sawdust was used to synthesize a zeolite-based stabilizer (GFAS) for immobilizing lead (Pb) and zinc (Zn) in tailings waste. The stabilizer was prepared through an alkali fusion–hydrothermal method, followed by phosphoric acid modification. Characterization by XRD, SEM-EDS, and BET revealed that GFAS possesses a Na-P1 zeolite structure (Na₆Al₆Si₁₀O₃₂) with a micro-mesoporous texture and a specific surface area of 35.00 m²/g, representing a 10-fold increase over raw sawdust. The cation exchange capacity (CEC) of GFAS reached 57.08 cmol⁺/kg, a 116-fold enhancement. The stabilization mechanism involved synergistic physical adsorption, chemical precipitation (e.g., Pb₃(PO₄)₂, Zn(OH)₂), and ion exchange. This study presents a sustainable “waste-treats-waste” strategy for effectively reducing the mobility of heavy metals in tailings waste, thereby contributing to the remediation of seepage from tailings pond foundations. Full article

Arbuscular mycorrhizal fungi (AMF), which significantly enhances the absorption capacity of plant roots, forms a mutually beneficial symbiotic relationship with plants and is known as the “underground internet of plants”. To explore the community characteristics, environmental driving factors, and growth-promoting effects of AMF on maize in saline–alkaline habitats, this research attempts a survey of the rhizosphere soil of saline–alkali maize fields in four areas of northern Xinjiang (20 samples). High-throughput sequencing and morphological methods were used to analyze the diversity of AMF, and the correlation analyses of Mantel and Pearson were used to explore the relationship between AMF and soil environmental factors. The results showed that eleven genera of AMF belonging to three orders and seven families were identified in the rhizosphere soil of maize in Xinjiang, and Glomus was the absolute dominant group. The relationship analysis of the environmental factors and diversity of AMF shows that total nitrogen, total potassium and acid phosphatase are the main factors affecting the community structure of AMF. Through spore isolation and pot experiments, Rhizophagus intraradices, Acaulospora denticulata and Glomus melanosporum were successfully screened and identified. Among them, Rhizophagus intraradices, which can effectively improve the plant biomass, promote the root growth and enhance the absorption of phosphorus and potassium nutrients, promoted the growth of maize remarkably. This study systematically revealed the diversity of AMF as an environmental driving mechanism as well as plant growth promoter, establishing it as a candidate for application in the maize rhizosphere in northern Xinjiang. This provides a theoretical basis for AMF resource development and agricultural application in this saline–alkali area. Full article

Background: The ATP-binding cassette (ABC) G subfamily, a key member of the ABC protein family, mediates plant stress responses by transporting metabolites across membranes, but its mechanism of action in tomato (Solanum lycopersicum L.) remains poorly understood. Methods: We systematically analyzed the evolutionary relationships, structural characteristics, stress-responsive expression patterns, and functional roles in response to saline-alkali stress of the SlABCG gene family in tomato, using a combination of approaches including phylogenetic analysis (MEGA), gene structure and motif analysis (GSDS, MEME), cis-acting element prediction, homology analysis, transcriptome analysis, protein-protein interaction prediction, and qRT-PCR validation. Results: We identified a total of 41 SlABCG genes from the tomato genome. These genes, together with 43 ABCG genes from Arabidopsis thaliana, were clustered into five distinct clades. There are 35 collinear gene pairs between the SlABCG gene family in tomato and the ABCG gene family in Arabidopsis, while 39 collinear gene pairs exist among ABCG genes within the tomato genome itself.The promoter regions of SlABCG genes contain cis-acting elements associated with responses to salicylic acid, low temperature, and gibberellin stresses. Transcriptome sequencing revealed that six SlABCG genes responded to saline-alkali stress. Gene regulatory network prediction revealed that multiple genes related to saline-alkali stress were regulated. Expression profile analysis of the 25 upregulated genes revealed that all of them were significantly upregulated during the saline-alkali stress treatment. Conclusions: In summary, our results provide deep insights into the characteristics of the SlABCG subfamily, facilitate the design of effective analysis strategies, and offer data support for exploring the roles of ABCG transporters under different stress conditions. Full article

Solid waste-based cementitious materials (SWCMs) represent an innovative class of binders derived mainly from construction and demolition waste as well as industrial byproducts. Their application in recycled mortar offers a promising pathway to partially replace conventional cement, thereby advancing resource recycling and facilitating a low-carbon transition in the cement industry. This review systematically examines the properties, activation techniques, strength development, and corrosion resistance of recycled mortar prepared with SWCMs. Recycled powder (RP) and industrial solid waste have gelation potential, but their low reactivity requires activation treatment to enhance utilization efficiency. Activation methods, including thermal activation, carbonation, and alkali activation, effectively enhance reactivity and promote the formation of dense gel structures (e.g., C-(A)-S-H, N-A-S-H). While low replacement ratios optimize pore structure via the microfiller effect, higher ratios introduce excessive inert components, impairing mechanical properties. SWCMs demonstrate superior resistance to sulfate and chloride attacks, but their acid resistance is relatively limited. They also have excellent freeze–thaw resistance. SWCMs represent a viable and sustainable alternative to conventional cement, exhibiting commendable mechanical and durability properties when properly activated and formulated, thereby contributing to resource recycling and environmental sustainability in the cement industry. Full article

This study systematically compared ultrasound-assisted extraction (UAE) with five other methods (hot water extraction (HWE), microwave-assisted extraction (MAE), acid extraction (FTACP), alkali extraction (FTAIP), and enzyme-assisted extraction (EAE)) for their effects on the yield, physicochemical properties, and bioactivities of Rosa laevigata Michx. polysaccharides. The results demonstrated UAE’s superior performance: it achieved a higher polysaccharide yield (31.27%) than HWE, FTACP, and FTAIP, approaching that of MAE and EAE. SEM observation revealed that UAE-derived polysaccharides exhibited a uniform porous network with smooth surfaces and excellent dispersibility, outperforming the irregular aggregates or structural loosening observed in other methods. Notably, UAE polysaccharides showed remarkable cholesterol-binding capacity (31.18 mg/g) and FRAP reducing power (0.0423 mmol/g), which highlights their potential for functional food applications. Structural analyses (FT-IR, XRD, TGA) confirmed that UAE better preserved the native conformation and thermal stability of polysaccharides, whereas chemical (FTACP/FTAIP) and high-temperature (MAE) methods induced molecular degradation. In conclusion, UAE, as an eco-friendly and low-denaturation technique, offers an optimal strategy for the high-value utilization of R. laevigata polysaccharides. Full article

Copper anode slime (CAS), obtained from non-standard anodes by pyro-hydrometallurgical electronic waste (e-waste) processing, contains high concentrations of lead, tin (as metastannic acid), and base (Cu, Fe, Zn), precious (Au, Ag), and technological metals (In, Ga, Ge), which limit the efficiency of conventional valorization methods. In this study, an integrated alkali fusion–leaching process was applied to non-standard CAS. Thermodynamic modeling defined the key parameters for selective phase transformations and efficient metal separation. These parameters were experimentally investigated, and the optimized fusion conditions (CAS:NaOH = 40:60, 600 °C, 60 min), followed by water leaching (200 g/dm³, 80 °C, 60 min, 250 rpm), resulted in >97% Sn removal efficiency. Simultaneously, Au and Ag losses were negligible, resulting in solid residue enrichment. Oxidant addition (NaNO₃) did not improve Sn removal but increased Fe, Pb, and Ag solubility, reducing selectivity. The scaled-up test confirmed process reproducibility, achieving 97.75% Sn dissolution and retention of precious metals in the PbO-based residue (99.99% Au, 99.78% Ag). Application of an integrated thermodynamic modeling, laboratory optimization, and scaled-up validation approach to non-standard CAS provides a relevant framework for a selective, efficient, and scalable method addressing industrial needs driven by increased e-waste co-processing, contributing to sustainable metal recovery. Full article

Fullerenes were modified into fulleramines by the wet chemical method, and then a CoRu/CNB bimetallic catalyst with defect-rich carbon-coated CoRu alloy and Ru NPs anchored on N- and B-doped carbon, promoting full pH hydrogen evolution, was prepared by condensation reflux and pyrolysis. Structural analysis indicates that the carbon layer endows the catalyst with excellent acid/alkali corrosion resistance, and the defect-rich characteristics expose more active sites. This catalyst only requires overpotentials of 21, 33, and 56 mV to drive HER to a current density of 10 mA cm⁻² in alkaline, acidic, and neutral solutions, featuring a rapid kinetic process and a large electrochemically active surface area. The synergistic effect of CoRu alloy and Ru NPs promotes charge redistribution and accelerates electron transfer, enabling CoRu/CNB to exhibit electrochemical activity and stability far exceeding that of commercial Pt/C in 1 M KOH, 0.5 M H₂SO₄, and 1 M PBS media. Full article

To address the issues of insufficient protection and poor durability in concrete during service, this study developed a novel polymer–silicate composite gel system by combining silane with fluorocarbon resin emulsion and applied it to mortar specimens. The chloride ion resistance enhancement of mortar provided by the novel gel system was evaluated using the RCM method and natural chloride ion penetration tests, with SEM images employed to analyze its anti-permeation mechanism. Results indicate that the chloride ion migration coefficient of the novel composite gel system is 4.91 × 10⁻¹² m²/s, representing a 63.97% reduction compared to the single fluorocarbon gel system. Within the 0–5 mm depth range, free chloride ion contents at 14, 28, and 56 days decreased by 55.35%, 50.10%, and 43.64%, respectively, demonstrating excellent resistance to chloride penetration. Acid and alkali resistance tests demonstrated that the system retained the inherent corrosion resistance of the fluorocarbon component. Carbonation tests demonstrated that the system exhibited a slight decrease in carbonation resistance compared with the pure fluorocarbon gel system, while still maintaining a satisfactory performance level. Overall, the polymer-silicate composite gel system significantly enhanced the mortar’s resistance to chloride ion penetration. Full article

While numerous extraction methods have been applied to the brown algae Saccharina latissima, a systematic evaluation of how individual extraction parameters influence the extraction of each target polysaccharide has not previously been reported. Accordingly, this study compared conventional and advanced techniques for extracting fucoidan, laminarin, and alginate from pre-treated biomass. Conventional methods employed diluted acid (0.01 M and 0.1 M HCl), diluted alkali (0.01 M and 0.1 M NaOH), and hot water (121 °C for 30/60 min) for extraction. Advanced techniques involved pressurized liquid extraction (PLE) using water and moderate electric field (MEF) extraction with conditions optimized by statistical experimental design. Pre-treatment with aqueous ethanol removed 30% ash and eliminated mannitol, improving extraction selectivity. The results demonstrated fucoidan yields of 31% with 0.01 M HCl and 46% with 0.1 M NaOH, while 0.01 M NaOH facilitated laminarin co-extraction (45%). Alginate, as a mannuronic acid polymer, was obtained at 9% yield with 0.1 M HCl, 42% yield with 0.1 M NaOH, and 27% with pressurized hot water for 30 min. High-temperature, short-duration PLE further improved alginate yield, while MEF showed limited gains due to high ionic content but demonstrated potential under optimized settings. The results support a cascading biorefinery approach in which different polysaccharide fractions can be sequentially obtained, contributing to more sustainable seaweed valorization. Full article

Milk and dairy products are a vital source of nutrients. This study aimed to evaluate the impact of pasteurization and the choice of derivatization method on the fatty acid (FA) profile in cream, a milk fat-rich product. Sixty cream samples (pre- and post-pasteurization) were analyzed. Two derivatization procedures were used: acid-catalyzed (1% H₂SO₄ in methanol following hexane extraction) and alkali-catalyzed (0.2 M KOH in methanol). FA methyl esters (FAMEs) were quantified using GC–FID. A total of 34 FAs were detected. The acid derivatization method was significantly more efficient for quantification, yielding higher overall FA concentrations (e.g., 302.26 μg/mL vs. 62.66 μg/mL pre-pasteurization). Pasteurization significantly altered the FA profile by reducing the overall content of FAs (especially SFAs and PUFAs), suggesting thermal degradation. Conversely, concentrations of FAs with unusual chain lengths (e.g., C15:1, C17:0) increased, likely due to release from complex lipids. The FA profile in cream is sensitive to processing. Acid-catalyzed derivatization is the recommended method for accurate quantitative FA analysis in cream. The stability of milk fat confirms its importance for product quality and potential use in various bioformulations. Full article

Microbial hydrocarbon degradation mediated by natural/modified clay minerals represents an eco-friendly and economically viable remediation strategy for hydrocarbon contamination. However, its effects are not always positive as they depend on multiple factors, including clay mineral types, modification methods, microbial species, and hydrocarbon substrates. This review systematically synthesizes existing fragmented studies concerning the impacts of natural clay minerals, modified clay minerals (acid/alkali/thermal/organic/metal ion), and clay minerals containing composite materials on microbial hydrocarbon biodegradation. Based on current findings, future research should prioritize the following recommendations: (1) avoid using concentrated strong acids in acid activation; (2) exclude metal cations that induce strong adsorption (reducing hydrocarbon bioavailability) or trigger excessive interlayer hydrolysis (some trivalent cations) in metal cation modification; (3) eliminate biologically toxic agents during organic modification; and (4) expand understanding of alkali/thermally modified clay minerals and clay mineral-containing composite materials in this direction. Natural/modified clay mineral-mediated microbial degradation is a highly promising remediation technology for hydrocarbon contamination and poised to advance and achieve breakthroughs through continuous synthesis of knowledge and innovation. Full article

Based on the physicochemical properties of waste phosphate-based rare earth phosphors containing glass, this paper proposes a novel recovery method for rare earth elements (REEs) that integrates pre-enrichment, alkali roasting, and enhanced leaching. Initially, preliminary enrichment of REEs was achieved through sieving to remove silicon (from glass components) and pickling to reduce calcium content (originating from calcium phosphate compounds). The enriched material was then subjected to alkaline roasting, followed by washing for impurity removal, hydrochloric acid leaching, and finally oxalic acid precipitation to extract the rare earth elements. Experimental results demonstrate that the overall recovery rate of rare earth oxides (REO) reached 96.6%, indicating highly efficient extraction and separation of REEs from the waste phosphors. Furthermore, the mechanism of the alkali roasting process was investigated via differential thermal analysis (TG-DSC). Microstructural and phase changes in the waste phosphors before and after roasting were systematically characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that green phosphor (REPO₄) was converted into rare earth oxides and water-soluble sodium phosphate under alkaline roasting conditions. The Na₃PO₄ could be effectively removed through washing, while the rare earth elements were retained in the form of oxides within the washed residue. This study provides an important theoretical foundation and technical approach for the efficient recovery of rare earth resources from waste phosphate-based phosphors. Full article

Seaweed holds significant promise as a renewable feedstock for bioenergy due to its rapid growth, carbon sequestration capacity, and non-competition with terrestrial agriculture. This review examines recent progress in multi-method synergies for optimized energy conversion from seaweed biomass. Physical pre-treatments (e.g., drying, milling, ultrasound, microwave) enhance substrate accessibility but face energy intensity constraints. Chemical processes (acid/alkali, solvent extraction, catalysis) improve lipid/sugar recovery and bio-oil yields, especially via hydrodeoxygenation (HDO) and catalytic cracking over tailored catalysts (e.g., ZSM-5), though cost and byproduct management remain challenges. Biological methods (enzymatic hydrolysis, fermentation) enable eco-friendly valorization but suffer from scalability and enzymatic cost limitations. Critically, integrated approaches—such as microwave-solvent systems or hybrid thermochemical-biological cascades—demonstrate superior efficiency over singular techniques. Upgrading pathways for liquid bio-oil (e.g., HDO, catalytic pyrolysis) show considerable potential for drop-in fuel production, while solid-phase biochar and biogas offer carbon sequestration and circular economy benefits. Future priorities include developing low-cost catalysts, optimizing process economics, and scaling synergies like hydrothermal liquefaction coupled with catalytic upgrading to advance sustainable seaweed biorefineries. Full article

To address the severe challenge of soil salinization, effective soil amelioration methods are urgently needed; however, current research on the microbial mechanisms of the combined application of multiple amendments is insufficient. Therefore, this study aims to investigate the impacts of biochar combined with humic acid (HA) on the physicochemical properties and microbial community structure of saline–alkali soils by a field experiment. The results showed that the co-application treatments significantly improved soil physicochemical properties and increased bacterial community richness; specific effects depended on the biochar feedstock. Notably, the H-MBC treatment was the most effective in reducing soil electrical conductivity (EC) by 44.1%, while the H-SBC treatment most significantly increased soil water content by 80.3%. Stochastic processes influenced the assembly of microbial communities, particularly the co-application group, forming a more complex and stable microbial network. Furthermore, Spearman correlation and random forest analyses revealed EC, nitrate nitrogen, and available phosphorus as the primary variables affecting microbial communities. These findings support the potential of the combined application of biochar and HA for saline–alkali soil amelioration, as this strategy mitigates salt stress and increases nutrient availability, thereby reshaping microbial communities toward states conducive to ecological restoration. Full article