Search Results (376)

Confronted with severe global challenges, including water scarcity, excessive use of chemical fertilizers and pesticides, and heavy metal contamination in soils, conventional agricultural technologies exhibit marked limitations in integrated water–fertilizer management and non-point source pollution control. Leveraging their excellent water retention capacity, intelligent sustained-release properties, and environmental responsiveness, hydrogels offer innovative solutions to advance sustainable agricultural development. This review comprehensively outlines the fundamental types, crosslinking mechanisms, and key functional properties of hydrogels, with a focused discussion on their agricultural deployment as high-efficiency soil conditioners, fertilizer vectors, and pesticide carriers; it deciphers the microscopic water-holding mechanisms under the tristate water model, delineates the divergent water-uptake and retention behaviors between ionic and non-ionic hydrogels, and clarifies the cyclic water-holding and release mechanisms of hydrogels during soil amelioration. Thise paper further synthesizes hydrogel-enabled environmental remediation applications, in which heavy metals and pesticide residues in soils and aquatic systems are removed via functional-group coordination adsorption or photocatalytic degradation; concurrently, hydrogels have been shown to activate plant systemic immunity through calcium-signaling pathways, thereby inducing broad-spectrum antiviral defense responses. Moreover, hydrogels can be integrated into precision agriculture frameworks to enable real-time monitoring of crop physiological status and to support targeted irrigation and fertilization management. This work also evaluates the role of hydrogels in promoting seed germination, root system development, crop metabolic regulation, and stress resilience, while introducing tailored application strategies across distinct plant growth stages. Their documented economic advantages include water conservation, enhanced crop yields, reduced dependence on synthetic fertilizers, and lower labor costs. Nevertheless, the large-scale implementation of hydrogels continues to face multifaceted challenges—particularly poor degradability and latent ecological risks, as conventional polyacrylamide (PAM)-based gels resist soil mineralization and retain potentially neurotoxic monomers, leaving a critical gap in multi-annual field data concerning their non-target interference with native soil aggregate evolution, pore distribution, and rhizospheric carbon–nitrogen footprints. Mechanistically, many hydrogels with tensile strengths below 1 MPa are highly susceptible to three-dimensional network collapse under high-salinity osmotic shock and tillage mechanical stress, exhibiting a precipitous drop in water retention after more than three wet–dry cycles due to deficient long-term structural stability. Compounding these technical gaps are elevated production costs and low farmer adoption, driven by the absence of texture-specific performance thresholds—such as an available water increment ≥ 40% for sandy soils—and the lack of established life-cycle cost models and farmer incentive mechanisms for bio-based hydrogels. Moving forward, hydrogel technology should pivot toward materials innovation and cost-reduction engineering to broaden its applicability, employ ≥3-year, multi-habitat regional trials to delineate ecological benefit–risk boundaries, and ultimately position hydrogels as pivotal enablers of sustainable, green agricultural paradigms. Full article

Steel/tin bimetallic components fabricated using traditional casting processes have inherent drawbacks, including complicated preparation procedures and a relatively low interfacial bonding strength. To efficiently create metallurgical composite steel/tin bimetallic structures under complex service conditions, we utilized TIG-based additive manufacturing with front wire feeding to prepare the components. The effects of the substrate inclination angle on the macroscopic morphology of the deposited layer, interfacial phase composition, the growth behavior of intermetallic compounds (IMCs) at the bimetallic interfaces, and interfacial mechanical properties were investigated. Our results show that macro-structural defects like cracks, voids and pores were not observed at the steel/tin interfaces. The grains of the interface IMCs were mainly composed of Fe₃Sn, FeSn₂ and FeSb₂ phases; Fe-rich microspheres were dispersed inside the deposited tin layer. Under horizontal substrate conditions, deposited layer morphology and IMC layer thickness presented symmetric distributions. When the inclination angle of the substrate reached 30°, the deposited layers exhibited an asymmetric teardrop morphology, resulting in an increased layer height and width and penetration depth. Meanwhile, tin alloy grains were significantly refined; more high-angle grain boundaries (HAGBs) were formed at the spreading fronts of molten droplets. Tin alloy hardness was improved via synergistic dispersion and grain boundary strengthening. This work reveals the inclination–morphology–microstructure–property correlation, fills the research gap in inclined substrate arc additive manufacturing of steel/tin bimetals, and provides a theoretical foundation for engineering applications. Full article

Absorbent pads are important materials for regulating exudate and local microenvironments in the packaging of high-moisture perishable foods. However, conventional absorbent pads often suffer from limited functionality, insufficient liquid retention, and a lack of active responsiveness. Hydrogels and aerogels, with tunable three-dimensional polymer networks, provide an important material basis for the design of new functional absorbent pads. This review focuses on the relationships among structure, function, and application, and compares hydrogels and aerogels in terms of network composition, crosslinking strategies, water absorption and retention mechanisms, and active compound loading and release behaviors. Structural design strategies, including multilayer structures, Janus structures, gradient pore structures, and micro/nano-reinforcement, are also summarized. On this basis, recent applications of hydrogel- and aerogel-based absorbent pads in the packaging of meat, aquatic products, fruits, vegetables, and edible fungi are discussed. Finally, the key challenges facing gel-based absorbent pads are analyzed, including adaptation to real food systems, release regulation, food-contact safety, and industrial-scale production. This review establishes a structure–function–application framework for gel-based absorbent pads and offers insights for designing sustainable active and intelligent food packaging. Full article

Although canna (Canna edulis Ker) starch possesses high swelling power, it remains an underutilized resource. This study aimed to engineer highly porous, food-grade canna starch aerogels as carriers for cyanidin-3-glucoside (C3G), incorporating enzymatically modified starch fractions prepared via α-amylase hydrolysis followed by lyophilization. Moderate enzymatic modification (sample AG1) effectively tailored the aerogel architecture by selectively removing amorphous regions. This targeted hydrolysis yielded a highly interconnected, hierarchical porous network with a high porosity (92%). Importantly, although this architectural transformation increased the average macroscopic pore size, it preserved mechanical integrity, as evidenced by a compressive strength exceeding 4000 kPa. In contrast, excessive hydrolysis led to pore collapse and structural failure. The AG1 aerogel exhibited a markedly enhanced C3G equilibrium adsorption capacity (43.9 mg/g), outperforming the native starch aerogel (36.0 mg/g). Adsorption data adhered to pseudo-second-order kinetics, indicating that this model provided a better description of the adsorption process, while the underlying adsorption mechanism may involve interactions between C3G and the aerogel matrix, potentially including hydrogen bonding. These results suggest that controlled enzymatically hydrolysis may provide a useful strategy for modulating the hierarchical microstructure of canna starch aerogels, thereby supporting their potential as effective carriers for sensitive bioactive compounds in functional food systems. Full article

Biochar is a porous carbonaceous material synthesized through the pyrolysis of diverse biomass resources, including agricultural and forestry residues as well as livestock manure. It possesses superior characteristics such as a large specific surface area, adjustable pore architecture, abundant surface functional groups, and favorable electrical conductivity. With the increasingly severe global energy shortage and environmental pollution problems in recent years, biochar has emerged as a green, low-cost functional material with distinct application superiority in multiple key research directions, including energy storage and conversion, chemical catalysis, environmental restoration, and signal sensing and detection. This study comprehensively summarizes the latest research advances of biochar in the aforementioned application fields, focusing on innovative achievements in photocatalytic and electrocatalytic hydrogen generation, supercapacitors and electrochemical energy storage systems, persulfate activation technology, carbon dioxide capture, remediation of heavy metal and organic contaminants, volatile organic compound (VOC) adsorption, as well as electrochemical sensing devices. Existing research results demonstrate that modification strategies including metal and non-metal doping, surface oxidation treatment, and compounding with semiconductors or metal oxide materials can effectively improve the catalytic activity and functional performance of biochar. Furthermore, this paper prospects the future interdisciplinary development trends of biochar, analyzes the existing research gaps in mechanism exploration, structural optimization design, and industrial large-scale preparation, and provides theoretical and practical references for the further popularization and application of biochar in sustainable energy development and environmental governance fields. Full article

Electromagnetic wave absorption ability and mechanical strength are critical performance metrics for cement-based microwave-absorbing materials. Enhancing electromagnetic wave absorption efficiency typically involves the incorporation of functional phases and optimization of pore structures. However, these modifications often introduce challenges, such as interfacial incompatibility between the functional phase and cement matrix, and reduced material density, which can compromise mechanical integrity. This study presents a structurally engineered, high-performance cement-based microwave-absorbing material fabricated from solid waste materials. By leveraging the poor interfacial compatibility between rubber powder and cement paste, the material achieves increased porosity, thereby improving impedance matching. Additionally, the presence of abundant dielectric and magnetic components in slag significantly enhances electromagnetic wave dissipation. Through the synergistic tuning of impedance matching and dissipation capacity, the cement-based microwave-absorbing material demonstrates a substantial improvement in electromagnetic wave absorption, with the absolute value of its reflection loss increasing by 2.8 times after CO₂ curing. Furthermore, the application of CO₂ curing technology facilitates the transformation of alkaline compounds such as Ca(OH)₂ into CaCO₃, resulting in notable gains in mechanical performance—compressive strength and flexural strength are elevated by 38% and 23%, respectively. This work not only achieves a balanced optimization of electromagnetic wave absorption and mechanical robustness in cement-based materials but also offers a sustainable pathway for the high-value utilization of industrial solid waste. Full article

A previous investigation on limonene (LM), perillyl alcohol (POH), and carveol (CV), focused on the structure–activity relationship and hydroxyl group, documented that the presence of the hydroxyl group influences the pharmacodynamic potency of these agents, inhibiting smooth muscle contraction with the order of potency: POH > CV > LM. That investigation also suggested a mechanism of action, which importantly included activity on the voltage-dependent calcium channel. Here, we investigated whether this structure–activity relationship also applies to nerve excitability (an activity greatly dependent on sodium channels) using compound action potential (CAP) recordings from mouse sciatic nerves and in silico simulations. POH, CV, and LM inhibited both the positive amplitudes and conduction velocities of the two CAP components in a concentration-dependent manner, with IC₅₀ values of 0.8, 1.0, and 4.3 mM (1st component) and 0.6, 0.6, and 3.0 mM (2nd component) for amplitude, and 2.4, 2.4, and 7.1 mM (1st component) and 1.0, 2.6, and 4.3 mM (2nd component) for conduction velocity. The order of pharmacodynamic potency, thus, was POH = CV > LM. In silico simulation demonstrated that POH and CV penetrate the Nav 1.6 and accommodate in the channel at the interface between the selectivity filter and the central cavity, a position very favorable to block the channel pore. In contrast, LM exhibited a markedly different docking profile, suggesting that LM binding is less likely to directly obstruct sodium permeation. In conclusion, the three substances investigated inhibited nerve excitability, but those with a hydroxyl group demonstrated greater pharmacodynamic potency. Full article

This research explores the production of activated carbon from a lignocellulosic precursor, corn cobs, as a potential method for the removal and adsorption of phenolic and nitrophenolic compounds. Colombia is a major corn producer, with a national production of 1,559,194 tons in 2024. Currently, approximately 0.5 to 3.2 kg of corn residue per kg of product is not commercially utilized. The objective is to focus on the removal of phenol, 2-nitrophenol, 4-nitrophenol, and 2,4-dinitrophenol from simulated solutions to evaluate the adsorption capacity under optimal conditions. Phenolic and nitrophenolic compounds are considered highly toxic molecules for the environment, especially in the plastics and agrochemical production sectors. These compounds are pollutants in wastewater due to their impact on aquatic life and human health. This not only contributes to the utilization of residual biomass but also to the circular economy by promoting its valorization in environmental remediation processes. The diameter and average volume of the pores are large enough to promote rapid diffusion kinetics of the phenolic compounds within the pore structure, which varies from 0.207 to 0.544 cm³ g⁻¹, and their adsorption capacity. The most adsorbed phenol was found to be 4-nitrophenol, with up to 97 mg of contaminant (4-nitrophenol) adsorbed per gram of activated carbon (sample designated AC-TK), at initial concentrations ranging from 0.0 ppm to 3.0 ppm. Furthermore, magnetite plays a crucial role in the adsorption of 2-nitrophenol. With this compound, up to 86 mg of 2-nitrophenol per gram of activated carbon was adsorbed at a concentration of 14 ppm, whereas without magnetite, a smaller amount was adsorbed at lower initial concentrations (ppm) for the same compound. Full article

Diatoms are microscopic algae with silica walls; they evolved relatively recently compared to other algal groups but have the greatest diversity of any and are abundant enough to contribute a fifth of the oxygen in the atmosphere and to have accumulated fossil mineral deposits (diatomaceous earth). Among the most recent and most diverse diatom genera is Mastogloia, with over 370 valid taxa but so far no pattern of phylogenetic relationships among the species. The genus is defined by the presence of chambers (partecta) on the girdle bands, which are as varied as the valve shapes and pore patterns. Mastogloia decussata was described in 1892, but its structure is still poorly understood, including whether it has axial costae and the nature of a V-shaped structure reported in 1970. A similar species, M. singaporensis, differs in having narrower, quadrate partecta that occupy only the middle half of the band; it has axial costae. We have observed several populations with quadrate partecta extending nearly to the apices in samples from Micronesian and Caribbean islands; such specimens have also been reported in the literature misidentified as M. decussata. The objective was to establish the ultrastructure of these species. Four major findings are as follows: (1) We establish the correct description of M. decussata with a neotype and show that it has axial costae; (2) we show that it has compound partecta with intrapartectal cylinders; (3) we describe one new species, M. paddocketkempii Lobban & J.A.B.Valencia, which also has compound partecta; (4) we show that all have dual pseudoloculate valve walls with interior and exterior pseudoloculi in slightly offset hexagonal arrays. The new species occurred in both ocean basins and may include simulacra, but we could not separate them morphologically. Detailed SEM of M. singaporensis shows its structural similarity to the other two species. Full article

This review provides an updated and comprehensive assessment of the current literature on quinoa (Chenopodium quinoa Willd.) saponins, with particular emphasis on pharmacological effects. Quinoa (Chenopodium quinoa Willd.) is an annual plant native to South America. Quinoa seeds are characterized by high nutritional value and are rich in proteins, lipids, carbohydrates, minerals, and saponins. Saponins are found in quinoa seeds and impart a bitter taste, which is why they are typically removed before seed consumption. Saponins have been characterized as antinutritional agents, but in recent years they have been investigated for their pharmaceutical applications. Protocols have been developed for the extraction of saponins from seeds, such as conventional solid–liquid extraction (maceration), ultrasound-assisted extraction, microwave-assisted extraction, enzyme-assisted extraction, and pressurized liquid extraction. Ultrasound-assisted extraction and microwave-assisted extraction are considered the most suitable methods for quinoa saponins. Quinoa saponins have shown promise as vaccine adjuvants. Furthermore, they have demonstrated direct anticancer activity, inducing apoptosis and inhibiting the proliferation of breast and colon cancer cells. In general, saponins can induce hemolysis at high concentrations through membrane disruption, primarily via lipid solubilization or pore formation. However, hemolytic activity varies significantly among different saponins and depends on their chemical structure and concentration. In vivo, they have not recorded adverse side effects at doses below 50 mg/kg body weight per day. More than 40 triterpenoid saponins, mainly derived from oleanolic acid, ederagenin, phytolaccagenic acid, and sergianic acid, have been identified in quinoa. Overall, although quinoa saponins have traditionally been considered antinutritional compounds, accumulating evidence indicates that they possess promising pharmacological properties, particularly as anticancer agents. Full article

The voltage-gated sodium channel Nav1.7 is a strongly validated target for the development of novel, non-opioid analgesics due to its genetic link to pain signaling. To accelerate the discovery of safe Nav1.7 modulators, this study outlines an integrated computational pipeline to repurpose FDA-approved drugs. A structurally complete model of the Nav1.7 central pore was generated via homology modeling from a high-resolution cryo-EM structure (PDB: 7W9K) to ensure a physically consistent model suitable for dynamic simulations. We conducted a structure-based virtual screening of 2296 FDA-approved compounds, identifying four promising candidates (DB04868, DB00941, DB01419, and DB15982) with strong predicted affinities ranging from −11.38 to −12.57 kcal/mol. Interaction fingerprinting revealed that binding is predominantly driven by hydrophobic contacts with conserved pore-lining residues, including Phe1503, Leu1010, and Ile1500. To validate these static predictions, the top protein–ligand complexes were subjected to single-replica 250 ns molecular dynamics (MD) simulations. Comprehensive trajectory analyses, including RMSD, RMSF, and principal component analysis, revealed a notable discrepancy between static docking scores and dynamic stability. The highest-scoring docking candidate, DB04868, exhibited substantial conformational flexibility and reduced stabilization under simulated physiological conditions. Conversely, DB01419, despite a lower initial docking rank, demonstrated the highest structural stability across all metrics and uniquely formed intermittent stabilizing hydrogen bonds. These findings underscore the value of post-docking MD validation in computational drug discovery and nominate DB01419 and DB15982 as candidate scaffolds that warrant subsequent experimental validation, including electrophysiological characterization and Nav-isoform selectivity profiling. We emphasize that these are computational predictions: in silico binding stability is not equivalent to functional inhibition of Nav1.7 currents, and the lead designations reported here remain hypothesis-generating until confirmed by patch-clamp and biochemical assays. Full article

Nereistoxin (NTX) and its derivative insecticides cartap and monosultap have been used for decades to control lepidopteran pests by targeting nicotinic acetylcholine receptors (nAChRs). Unlike neonicotinoid agonists that induce excitatory neurotoxicity, nereistoxin insecticides act as antagonists, blocking cholinergic neurotransmission. However, the molecular target and mechanism of action of these compounds remain incompletely understood. Here, we elucidated the mode of action of cartap and monosultap in Drosophila melanogaster through integrated genetic and computational approaches. Bioassays with Drosophila nAChR subunit mutants demonstrated that the α6 subunit is critically required for insecticidal activity of both compounds, with α6 knockout conferring approximately 10-fold resistance to monosultap and 7-fold resistance to cartap. Molecular docking of protonated NTX into an α6 homopentameric channel model revealed a “dual-anchor” blocking mechanism: the protonated amine forms electrostatic interactions with residue Glu267, while the dithiolane ring creates steric hindrance at residue Thr270. Pore diameter measurements showed an optimal binding cavity of 5.96–6.22 Å in the 267–270 region, narrowing dramatically to 1.64 Å at the deep gate (Ser278), explaining how NTX binding physically occludes the channel. Collectively, these results identify α6-containing nAChRs as the primary target of nereistoxin insecticides and provide a structural framework for understanding channel blockade, with important implications for resistance monitoring and the development of next-generation channel-blocking insecticides. Full article

Baijiu brewing generates large quantities of wastewater sludge, which presents major disposal challenges but contains abundant organic matter and nutrients, indicating great potential as a soil amendment. This study investigated the soil amendment effects of granulated and coated Baijiu brewing sludge through a 112-day soil column leaching experiment. Sludge particles were coated with sodium alginate (SA), polyvinyl alcohol (PVA), and ester gum (EG), and compared with untreated air-dried sludge (CK₁), uncoated granulated sludge (CK₂), compound fertilizer (F), and a blank control (B). The results showed that coated sludge treatments significantly increased soil leachate pH, total organic carbon, total nitrogen, total phosphorus, and total potassium, and exhibited obvious controlled-release effects on nitrogen, phosphorus, and potassium nutrients compared with uncoated sludge. Soil enzyme analysis indicated that SA treatment increased catalase activity, acid phosphatase activity was generally enhanced by sludge addition, and urease activity was reduced in coated sludge treatments. FTIR and BET analysis showed that both coated and uncoated sludge increased soil-specific surface area and changed soil pore structure. These findings confirm that granulated and coated Baijiu brewing sludge can be used as an effective slow-release soil amendment, and sodium alginate coating shows the most comprehensive improvement in multiple soil health indicators, with high application value for resource utilization of Baijiu sludge and soil quality improvement. Full article

Aluminum/magnesium (Al/Mg) hybrid structures are promising candidates for lightweight engineering, but reliable joining is still limited by brittle intermetallic compounds (IMCs), oxide films, pores, cracks, and corrosion-related degradation. This review summarizes recent advances in Al/Mg dissimilar-metal joining, including solid-state welding, fusion welding, brazing, resistance-based joining, and mechanical joining. Emphasis is placed on process characteristics, interfacial reactions, defect formation, mechanical properties, service reliability, and simulation-assisted process understanding. The reviewed studies indicate that joint reliability cannot be interpreted solely from IMC thickness; phase type, continuity, spatial distribution, interfacial morphology, and involvement in the fracture path are also critical. Solid-state and high-speed impact processes can restrict continuous Al–Mg reaction layers by reducing thermal exposure and promoting plastic contact, whereas fusion-based processes provide greater manufacturing flexibility but require stricter control of molten-pool behavior, Mg evaporation, porosity, and interlayer stability. Recent numerical simulations and data-driven studies are further discussed as tools for mechanism-guided parameter design. This review provides an integrated comparison of joining routes and highlights future needs for standardized testing, fatigue and corrosion evaluation, thermal-cycling assessment, coupled service-performance analysis, and process selection for engineering applications. Full article

The long-term reliability of XLPE submarine cable insulation is influenced by progressive thermal degradation during operation and subsequent seawater ingress caused by external damage. Although thermal aging and seawater exposure have been widely investigated individually, the influence of the prior thermal-aging state on the subsequent seawater-induced degradation behavior of XLPE remains insufficiently understood. In this study, XLPE insulation specimens prepared from the same commercial compound used for 500 kV submarine cables were subjected to sequential accelerated aging consisting of controlled thermal pre-aging followed by simulated seawater exposure. Broadband dielectric spectroscopy, AC breakdown testing with two-parameter Weibull analysis, scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR) were employed to investigate the evolution of electrical properties, surface morphology, and molecular structure. The results demonstrate that seawater-induced electrical deterioration strongly depends on the initial thermal-aging state of XLPE. Increasing thermal pre-aging duration resulted in progressively higher relative permittivity and dielectric loss, together with reduced characteristic breakdown strength after subsequent seawater exposure. Under the most severe condition of 1440 h thermal pre-aging followed by 672 h seawater exposure, the power–frequency relative permittivity increased by 32.1%, while the characteristic breakdown strength decreased by more than one-third compared with the initial state. SEM observations revealed that thermally pre-aged specimens developed accelerated surface damage during seawater exposure, including pores, cracks, corrosion pits, and honeycomb-like structures. FTIR analysis further indicated molecular-chain degradation and increased hydroxyl-related species during sequential aging. These results suggest that thermal-aging-induced molecular oxidation, polar-group formation, and microstructural defects enhance water and ion penetration pathways, thereby increasing the susceptibility of XLPE insulation to subsequent seawater-induced degradation. This study provides material-level experimental evidence for understanding sequential aging processes in submarine cable insulation and highlights the importance of considering historical thermal damage in future condition assessment and lifetime evaluation models. Since accelerated laboratory conditions were adopted, the results should be interpreted as comparative degradation characteristics rather than direct predictions of field-service lifetime. Full article