Search Results (4,912)

With the increase in voltage levels, higher requirements are imposed on the energy-dissipation capability of high-voltage direct current (HVDC) networks. Existing energy-dissipation schemes cannot satisfy the demands of future HVDC systems. In this paper, a composite energy-dissipation branch circuit based on liquid metal, zinc oxide varistors, and damping resistors is proposed for HVDC circuit breakers. First, the self-constricting arc initiation mechanism and energy-dissipation characteristics of gallium–indium–tin liquid metal are studied. The results show that the energy-dissipation process exhibits an obvious stage-wise characteristic. Subsequently, an energy-dissipation topology incorporating liquid metal elements is established. A simulation model for the liquid-metal module is developed using the Mayr arc theory, and the conductance evolution during arc initiation is simulated. The model is combined with a hybrid HVDC circuit breaker model for analysis. Finally, a composite energy-dissipation branch circuit is constructed. The energy allocation among different components and the corresponding power density are evaluated. In the case of connecting three liquid-metal components in series, the energy density reached 0.248 kJ/cm³, representing a 22.2% increase compared to the original. The results support the coordinated application of liquid-metal modules and conventional absorption units in HVDC circuit breakers. Full article

The degradation of agricultural soils and the low efficiency of conventional fertilizers pose significant challenges to sustainable agricultural production. In this context, nanobiofertilizers have emerged as a promising alternative for increasing nutrient availability and improving early plant development. This study evaluated the effect of a zinc oxide nanobiofertilizer (NBF-ZnO) synthesized via a green route using Mangifera indica leaf extract on the germination and early growth of maize (Zea mays L.) seedlings. The synthesized nanoparticles were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectroscopy to confirm their structural and optical properties. Subsequently, germination and early growth trials were conducted under four treatments: control, mango extract, conventional fertilizer (Triple 15), and NBF-ZnO, using soil affected by mining activities in the department of Cesar (Colombia). The results showed that the NBF-ZnO treatment achieved the highest germination (93%) and seedling growth (92.5%), outperforming the conventional fertilizer and the other treatments. Statistical analysis using the chi-square test confirmed significant differences between treatments (α = 0.05). These findings suggest that ZnO nanobiofertilizers obtained through green synthesis could represent a promising strategy for enhancing early maize development and contributing to the sustainable management of soils affected by mining activity. Full article

Carbonic anhydrases (CAs) are a class of zinc-containing metalloenzymes widely present in the biological world, catalyzing the reversible hydration of CO₂ to form HCO₃⁻ and H⁺. These enzymes play essential roles in pH homeostasis, gas exchange, metabolic regulation, and virulence expression in pathogens. In fungi, CAs mainly belong to the α- and β-classes and have undergone extensive diversification during evolution. In plant pathogenic fungi, the functions of CAs have extended beyond traditional metabolic roles, evolving into key “environmental adaptation and virulence regulatory factors.” This review takes Magnaporthe oryzae as a model organism and integrates recent advances in CA research across various microorganisms. It systematically summarizes the classification diversity, structural features, subcellular localization, and biological functions of fungal CAs. Particular emphasis is placed on the molecular profile, mitochondrial localization, physical interaction network, and multiple functional roles of the MoCA family members in conidial development, appressorium formation, oxidative stress response, HCO₃⁻ homeostasis, nitrogen metabolism, and mitochondrial energy metabolism. Based on these findings, this study proposes a multi-layered analytical framework integrating CA molecular characteristics, mitochondrial functional regulation, and fungal pathogenicity. It explores the potential of targeting fungal CAs for the development of novel selective fungicides and highlights key research directions, aiming to provide theoretical insights into plant-fungal interactions and innovative strategies for disease control. Full article

Ulcerative colitis (UC) is a chronic inflammatory disease characterized by persistent colonic inflammation, excessive oxidative stress, and impaired barrier function. Transition metal-based nanoparticles offer promising antioxidant platforms to address oxidative stress-related pathologies. To overcome the poor gastrointestinal stability of the potent dietary antioxidant epigallocatechin gallate (EGCG), we utilized zinc-coordinated EGCG (EGCG-Zn) nanoparticles (NPs), which function as a transition metal–phenolic network, to achieve sustained colonic release and overcome the poor gastrointestinal stability of free EGCG. The therapeutic efficacy and underlying mechanisms were evaluated in dextran sulfate sodium (DSS)-induced colitis in mice. Oral administration of EGCG-Zn NPs effectively reduced oxidative stress, suppressed pro-inflammatory cytokine production, alleviated colitis symptoms, and repaired the intestinal mucus and mechanical barriers. Mechanistically, transcriptomic analysis revealed that EGCG-Zn NPs pretreatment markedly reversed DSS-induced transcriptional alterations. Integrated K-means clustering and KEGG enrichment analyses further demonstrated that these protective effects were mediated by down-regulating inflammation-associated genes and up-regulating tight junction proteins, primarily involving the modulation of calcium signaling, T-cell differentiation, and the PI3K-Akt, Wnt, NF-κB, and TNF pathways. Collectively, these findings suggest that EGCG-Zn NPs alleviate DSS-induced colitis by mitigating inflammation, suppressing oxidative stress, and promoting epithelial barrier repair, supporting their potential as a functional nutraceutical for UC management. Full article

The increasing prevalence of antimicrobial resistance has stimulated the development of alternative antimicrobial materials capable of preventing microbial growth and biofilm formation. Chitosan, a natural polysaccharide derived from chitin through deacetylation, possesses intrinsic antimicrobial properties, biodegradability, biocompatibility, and low toxicity, making it an attractive matrix for nanocomposite materials. However, the antimicrobial efficacy of pure chitosan is often limited by different factors, such as pH sensitivity, mechanical weakness, and poor solubility at neutral pH. To overcome these limitations, researchers have developed chitosan composites containing nanoparticles to enhance antimicrobial and antibacterial efficacy. This review provides an update on the status of the action mechanisms, synthesis methods, antimicrobial and antibacterial performances, and potential biomedical applications of chitosan-based composites containing silver nanoparticles (AgNPs) or zinc oxide nanoparticles (ZnONPs). Full article

Given the urgent need to regulate oxidative stress microenvironments in chronic wound healing, hydrogel dressings that simultaneously integrate antioxidant, antibacterial, mechanically adaptive, and biocompatible properties are highly desirable. In this study, a natural polymer-based composite hydrogel dressing loaded with zinc-quercetin nanozyme (Zn-Q) was designed. The gel skeleton was constructed via a dual network of photocrosslinked methacrylated silk fibroin (SilMA) and mercaptolated hyaluronic acid (HA-SH) via thiol-ene click chemistry, with the catalase (CAT)-like Zn-Q nanozyme encapsulated in situ within the network, thereby achieving synergy between chemical crosslinking and dynamic metal-polyphenol coordination. Systematic characterization revealed that Zn-Q nanozyme adopted a stable octahedral coordination configuration, and its continuous porous structure exposed abundant catalytically active sites. The composite hydrogels exhibited a highly interconnected, three-dimensional (3D) porous morphology, with swelling ratios that increased significantly with Zn-Q nanozyme content (up to around 1082%). Rheological and mechanical tests demonstrated that although incorporating the nanozyme reduced the storage modulus, the reversible physical crosslinks formed via hydrogen bonding and coordination interactions endowed the material with excellent tensile toughness and energy-dissipation capacity, exhibiting typical Mullins softening behavior. Functional evaluation showed that Zn-Q nanozyme conferred superior free radical scavenging capability to the hydrogels and exerted dose-dependent inhibition against both Staphylococcus aureus and Escherichia coli. Furthermore, the hydrogels exhibited favorable adhesion to various wet organs and heterogeneous material surfaces, with hemolysis rates below 5% and cell viability exceeding 100% after 3 days of culturing with fibroblasts, confirming their excellent hemocompatibility and cytocompatibility. This study provides an experimental basis for developing a new type of wound repair materials that integrate antioxidant, anti-infective, and mechanically adaptive properties, holding significant application potential in oxidative stress-related tissue repair fields. Full article

Different flat-panel detector technologies are available for intraoperative fluoroscopy. This study compared orthopedic and trauma surgeons’ preference and subjective image quality among mobile C-arm systems equipped with amorphous silicon (a-Si), complementary metal oxide semiconductor (CMOS) or indium gallium zinc oxide (IGZO) detectors. Fluoroscopic imaging was performed on four human specimens at four anatomic locations at pulse rates of 1/s and 10/s in low- and high-dose settings using three C-arm systems. Subjective image quality was rated by two observers on 5-point Likert scales. Pairwise forced-choice comparisons of images with identical acquisition parameters were analyzed using a Bradley–Terry model. Across all images, CMOS- and IGZO-based systems were preferred over the a-Si-based system in 91.8% and 90.4% of comparisons, respectively (ORs 9.53 and 11.20; both p < 0.001). No significant overall preference was observed between the IGZO- and CMOS-equipped systems. Subjective image quality ratings were significantly higher for CMOS- and IGZO-based systems compared with the a-Si-based system, particularly for overall image quality and perceived noise, while no consistent differences in image quality were found between CMOS- and IGZO-based systems. Overall, the CMOS- and IGZO-based systems evaluated in this study were preferred over the a-Si-based system and achieved superior subjective image quality ratings. Full article

Nano-priming has emerged as a novel technology for improving seed germination, vigour, and stress tolerance, and enhancing nutrient uptake in cereal grains, especially rice and wheat. This study presents a bibliometric analysis of 6302 publications obtained by a Boolean search query from the Scopus database, executed in November 2025. The dataset was further refined by using strict inclusion–exclusion criteria and mapped for the intellectual, geographic, and collaborative structure of the research on the topic under study at the global level. Country-level research productivity, subject-area distribution, annual publication trajectories, source-level publication patterns, and co-authorship networks are part of this study. The analysis revealed a highly skewed global publication distribution dominated by China, India, and Pakistan, which are major global hubs for nanotechnology-assisted seed treatment research, on the nano-priming of seeds. Agricultural sciences, environmental sciences, materials science, and nanotechnology emerged as dominant interdisciplinary contributors to nano-priming research. Annual publication trends continue to show an exponential rise since 2013, driven by growing interests in nanotechnology-enabled crop improvement. Co-authorship analysis revealed dense collaborative clusters centred in South and East Asia, interconnected through key bridging authors. The bibliometric evaluation, together with evidence-based synthesis of experimental studies, highlighted zinc oxide, titanium dioxide, silver, iron oxide, chitosan, and carbon-based nanomaterials as the main hotspots driving physiological enhancement in rice and wheat through enzymatic activation, nutrient uptake, and stress-resilience pathways. Nanotechnology-based seed treatments in rice and wheat offer a promising and sustainable approach to enhance crop productivity, stress tolerance, nutrient-use efficiency, and global food security under changing environmental conditions. Full article

The photocatalytic degradation of the 2,5-diphenyl-1,3-oxazole (PPO) and 2-(4-biphenyl)-5-phenyl-1,3,4-oxadiazole (PBD), which are laser dyes and scintillator compounds, was investigated under ultraviolet (UV) light irradiation using pure and rare-earth (Sm³⁺, Eu³⁺, and Gd³⁺)-modified zinc oxide (ZnO) hierarchical flower-like microstructures. The synthesized photocatalysts (powder) were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD), confirming the formation of flower-like ZnO structures and successful modification by the oxides Sm₂O₃, Eu₂O₃, and Gd₂O₃. Residual concentrations of Zn²⁺, Gd³⁺, Sm³⁺, and Eu³⁺ in the treated aqueous solutions were determined by ICP-MS to evaluate catalyst stability, while chemical oxygen demand (COD) analysis was used to assess mineralization efficiency. For both PPO and PBD, the photocatalytic activity followed the order ZnO < ZnO/Gd₂O₃ < ZnO/Sm₂O₃ < ZnO/Eu₂O₃, which can be attributed to the enhanced charge separation and reduced electron–hole recombination caused by rare-earth ions, with Eu³⁺ providing the most effective electron trapping. PPO showed faster degradation than PBD, mainly due to the structure of the PBD molecule, which is more rigid and conjugated, owing to its higher resistance to oxidative degradation. Full article

Flexible thermoelectric textiles have emerged as promising materials for wearable energy harvesting and electrothermal applications because they combine mechanical flexibility with the ability to convert low-grade heat into electrical energy. In this study, reduced graphene oxide/zinc oxide/copper oxide (rGO/ZnO/CuO) hybrid nanocomposites were synthesized and deposited onto Cotton–Nylon–Spandex (80:15:05) stretch fabrics using a silicone elastomer-assisted coating process to develop flexible conductive textiles. The influence of nanocomposite loading (2–8 g/100 mL elastomer) on the structural, electrical, thermal, and thermoelectric properties of the coated fabrics was systematically investigated. SEM, EDX, XRD, and Raman analyses confirmed the successful formation and uniform distribution of the rGO/ZnO/CuO hybrid coating on the textile substrate. Increasing the nanocomposite loading progressively reduced the electrical resistance from approximately 42 to 18 MΩ, indicating the formation of an interconnected conductive network, while the Seebeck coefficient increased from 0.049 to 0.056 mV K⁻¹ (49–56 μV K⁻¹). The measured effective thermal conductivity of the coated textile decreased from approximately 12 to 2.68 W m⁻¹ K⁻¹, reflecting changes in the thermal transport behavior of the composite coating. The coated fabrics also exhibited stable electrical performance under repeated bending, stretching (up to 80% strain), and washing, together with improved thermal stability and uniform Joule-heating behavior. These results demonstrate that the rGO/ZnO/CuO hybrid coating provides an effective strategy for developing flexible, mechanically durable, and multifunctional conductive textiles with potential applications in wearable thermoelectric energy harvesting and smart heating systems. Full article

It can be argued that blends of biopolymers can be regarded as an economical and efficacious method for formulating blends with customised properties. In the context of immiscible and/or incompatible constituents, the use of a compatibiliser agent (i.e., physical or chemical compatibiliser) has been demonstrated to enhance specific properties, including ductility and hydrophobicity. In this study, biopolymer blends based on polylactic acid (PLA) and polyamide 11 (PA11), with and without a compatibiliser (ethylene butyl-acrylate glycidyl methacrylate; Elvaloy), and also in the presence of metal oxides, such as zinc oxide (ZnO) and titanium dioxide (TiO₂), were processed by melt mixing and characterised for their mechanical, rheological, thermal and hydrophobic behaviour, as well as for their photo-oxidation resistance. The presence of a compatibiliser appeared to have a beneficial effect on the system’s ductility and hydrophobicity, also changing the blend morphology and reducing the dimensions of the PA11-droplets. The complex nature of the systems in question means that the beneficial effect of the compatibiliser on the dispersion of metal oxides cannot be fully appreciated. The favourable dispersion of metal oxide particles, in conjunction with their selective location at the interphase between the two polymeric phases and/or in the more polar phase, reduces the photo-oxidation resistance of these systems. This aspect must be given due consideration. Full article

Against the backdrop of global climate change and the urgent need to decarbonize the construction sector, cement production remains a major contributor to anthropogenic CO₂ emissions, accounting for over 7% of the global total. Carbonation mixing has emerged as a promising green technology that integrates CO₂ sequestration with performance enhancement of cement-based materials. However, the combined effects of carbonation mixing and binary nano-oxide modification on the multi-performance attributes of cement mortars have not been systematically explored. This study aims to address this gap by investigating the synergistic modification of cement-based materials with nano-zinc oxide (nano-ZnO) and nano-zirconia (nano-ZrO₂) under carbonation mixing conditions. The results indicate that the quadratic polynomial models exhibit good-to-excellent goodness-of-fit, with the 28-day saturated water absorption model achieving an R² of 0.9650 and an adequate precision of 16.47, confirming reliable predictive capability. Compressive strength ranged from 62.29 to 116.45 MPa, representing a 90.05% increase in the lower limit and a 22.37% increase in the upper limit relative to the reference group. Nano-ZnO generally reduced early-age strength due to its retarding effect, while nano-ZrO₂ exhibited a continuous strengthening effect across the 0–10% dosage range. The optimal synergistic range for early-age strength was identified as 0–0.2% nano-ZnO and 0–2% nano-ZrO₂, whereas nano-ZrO₂ dominated long-term performance enhancement. Saturated water absorption decreased significantly from 3 to 28 days, reflecting progressive pore refinement through continued hydration and carbonation product filling. Autogenous shrinkage showed a non-monotonic trend with nano-ZnO content—initially increasing then decreasing—while drying shrinkage increased predominantly with nano-ZrO₂ dosage, attributed to increased capillary tension resulting from pore structure refinement. The carbonation environment accelerates CO₂ diffusion and reaction, generating stable calcium carbonate that partially fills microcracks and further refines the pore structure, which provides a viable technical pathway for developing low-carbon, high-performance cement-based composites, with the RSM-based optimization framework offering an optimization tool for tailored mix design in applications such as high-strength concrete, repair mortars, and prefabricated elements where early strength and dimensional stability are critical. Full article

The Lion Man sculpture (UNESCO World heritage), a left mammoth tusk and mammoth ivory fragments from the excavations in the Hohlenstein-Stadel cave, Lone valley, Swabian Alb, Germany, were non-invasively analysed by means of external ion beam analysis (IBA) at the microfocus beamline at the particle accelerator AGLAE. The Lion Man was reconstructed from about three hundred mammoth ivory fragments, while the tusk is a separate find, and the fragments are individual pieces that could not be placed in the Lion Man. A characteristic trace element fingerprint, based on zinc, bromine and strontium contents, was established according to previous IBA studies of Aurignacian-era mammoth ivory and allowed for a comparison of the mammoth ivory objects. The specific Hohlenstein-Stadel cave trace element fingerprint could be distinguished from that of other Aurignacian sites in Europe but closely resembles that of the contemporary ivories from the neighbouring Hohle Fels cave. Although this study highlights that the Lion Man sculpture is chemically inhomogeneous due to diagenetic alterations, the left tusk and individual ivory fragments are chemically very similar to the Lion Man. However, further analyses are required to relate them to the same animal. Secondary minerals such as black manganese oxide dendrites and iron-rich aluminosilicates could be identified on the Lion Man and the other ivory objects at the surface. While dendrites are a characteristic diagenetic feature of mammoth ivory, the origin of iron-rich aluminosilicates can be linked either to sediment traces or surface treatment and use wear of the sculpture. Iron-rich zones are identified on particular parts of the Lion Man, namely, at the snout and at the left forearm with decorative signs. The snout is also particularly enriched in carbon, whose origin still needs to be clarified. Full article

The work explores the effect of modifying thin ZnO and ZnO:V sol–gel films with graphene oxide (GO) dispersions on their structural and photocatalytic properties. The study has, for the first time, detected the effect of selective phase separation in sols, characterized by the separate crystallization of zinc and vanadium oxides upon adding GO dispersion into a mixed sol. Increasing the GO concentration in ZnO-VO₂ precursor sols improves the crystallinity of the material; films of the same composition without added GO are X-ray amorphous. Conversely, adding GO to unmodified ZnO sols causes a reduction in the crystallite size of the films, which increases with higher GO content. Notably, their photocatalytic activity varies non-monotonically: at 10 wt.% GO, it is minimal, while a further increase in the GO concentration leads to its improvement. An increase in the GO concentration in ZnO:V films causes a monotonically enhanced efficiency of photocatalysis. This may be related to the improved crystallinity and the formation of a percolation cluster from reduced graphene oxide. Full article

Ti₃C₂T_x MXene is an attractive conductive scaffold for lithium-ion battery anodes owing to its two-dimensional structure, hydrophilic surface chemistry, and tunable interlayer spacing; however, pristine MXene generally exhibits moderate lithium-storage capacity and suffers from restacking-induced loss of accessible active sites. In this study, Ti₃C₂T_x MXene@ZnO composites were prepared by growing ZnO on Ti₃C₂T_x MXene nanosheets with controlled growth times of 1, 2, and 3 h. The materials were characterized by FE-SEM, XRD, and N₂ adsorption–desorption measurements, and their electrochemical performance was evaluated in CR2032-type half-cells. Structural analyses showed that MZ-2h exhibited a more uniform distribution of ZnO particles, increased MXene interlayer spacing, and the highest BET surface area (42.77 m² g⁻¹) and total pore volume (0.1027 cm³ g⁻¹), whereas excessive ZnO growth for 3 h caused particle aggregation and reduced pore accessibility. Electrochemical measurements showed that MZ-2h delivered the best rate capability, maintaining 182.4 mAh g⁻¹ at 0.2 C and 48.0 mAh g⁻¹ at 5 C, together with the highest second-cycle Coulombic efficiency of 88.4%. These results demonstrate that controlling ZnO growth time is an effective strategy for balancing ZnO-derived lithium-storage contribution, particle dispersion, pore accessibility, and the MXene-based framework in Ti₃C₂T_x MXene-based hybrid anodes. Full article