Search Results (539)

The widespread application of detonation nanodiamonds (DNDs) is limited by surface-coated non-diamond sp² carbon impurities. In this work, an efficient salt-assisted catalytic purification strategy is developed to achieve selective oxidation removal of sp² carbon. DND black powder was mixed with various chloride, carbonate, and bicarbonate salts and thermally treated in air to systematically investigate the effects of anions and cations on purification efficiency. Thermogravimetric analysis reveals that all tested salts significantly reduce the oxidation onset temperature of sp² carbon and exhibit distinct catalytic trends: for anions, bicarbonates > carbonates > chlorides; for cations, Cs⁺ ≈ K⁺ > Na⁺. Among them, KHCO₃ introduced via a wet-wrapping method shows the optimal performance, lowering the oxidation temperature by approximately 160 °C. Moreover, the wet-wrapping process effectively suppresses particle sintering and agglomeration during purification, resulting in purified DNDs with reduced average particle size and markedly improved dispersibility. Mechanistic investigations demonstrate that free alkali metal cations act as active sites, preferentially catalyzing sp² carbon oxidation through a synergistic oxygen spillover–electron transfer mechanism. This study provides an effective and highly selective approach for DND purification. The proposed salt-assisted strategy, integrating catalytic oxidation and dispersion control, also offers valuable insights for the preparation of high-performance nanomaterials. Full article

Background/Objectives: The development of non-alcoholic fatty liver disease (NAFLD) is closely linked to oxidative stress and inflammation. Aerobic exercise has been shown to improve NAFLD, although its underlying mechanisms remain incompletely understood. This study utilized ApoE^-/- mice to investigate the role of Sestrin2 in aerobic exercise-induced amelioration of NAFLD. Methods: Random assignment of C57BL/6J and ApoE^-/- mice yielded four groups: C (control), CE (aerobic exercise), AS (ApoE^-/- control), and AE (ApoE^-/- aerobic exercise). Aerobic exercise lasting 12 weeks was administered to the CE and AE groups. Serum biomarkers were analyzed by ELISA, liver tissue morphology was assessed via HE and ORO staining, and macrophage polarization was evaluated through immunofluorescence. Additionally, mRNA and protein expression levels were measured by qPCR and Western blot. Results: Aerobic exercise reduced liver wet weight, lipid accumulation, and steatosis in ApoE^-/- mice. Aerobic exercise attenuates hepatic oxidative stress, and upregulated the expression of regulation oxidative stress related gene and proteins of Nrf2, HO-1, CAT, and SOD1 in ApoE^-/- mice. Aerobic exercise promoted a shift in macrophage polarization from the pro-inflammatory M1 phenotype toward the anti-inflammatory M2 phenotype in the liver, and significantly reduced TNF-α and IL-1β levels, accompanied by upregulation of Sestrin2 expression, enhanced AMPK phosphorylation, inhibited mTORC1 in the liver. Conclusions: These findings suggest that aerobic exercise alleviates oxidative stress and inflammation in NAFLD, with Sestrin2 activation playing a central role. Full article

Background/Objectives: High-altitude pulmonary edema (HAPE) remains a serious condition with limited preventive options. This study evaluated the prophylactic protective effects of nebulized human umbilical cord mesenchymal stem cell-derived extracellular vesicles (hUC-MSC-EVs) in a rat model of hypobaric hypoxia-induced lung injury and explored potential mechanistic clues, with a focus on oxidative stress and TEK/Tie2 signaling. Methods: Rats were exposed to hypobaric hypoxia (47 kPa; 9.7% O₂) for 72 h and received prophylactic nebulized hUC-MSC-EVs (300 μg/rat). Lung injury was evaluated by histopathology, wet-to-dry ratio, and bronchoalveolar lavage fluid (BALF) protein concentration. Invasive pulmonary function indices were measured using a forced oscillation system. BALF cytokines (TNF-α, IL-6, and IL-10), reactive oxygen species (ROS), and TEK/Tie2 expression in lung tissue were assessed. In addition, transcriptome sequencing (RNA-seq) was performed to characterize global transcriptional changes. N-acetylcysteine (NAC), a classical antioxidant, was included as an auxiliary mechanistic intervention to assess the association of ROS with TEK/Tie2 changes. Results: Compared with hypoxia controls, prophylactic nebulized hUC-MSC-EVs reduced histopathological injury, pulmonary edema, and barrier leakage, and improved pulmonary function indices. hUC-MSC-EV intervention also attenuated inflammatory responses in BALF, with decreased TNF-α and IL-6 and increased IL-10. Hypobaric hypoxia increased ROS accumulation and decreased TEK/Tie2 expression, whereas nebulized hUC-MSC-EVs reduced ROS and partially preserved TEK/Tie2 expression. NAC pretreatment similarly reduced ROS and was accompanied by Tie2 preservation. Conclusions: Prophylactic nebulized hUC-MSC-EVs mitigated hypobaric hypoxia-induced lung injury, accompanied by reduced oxidative stress, improved vascular barrier integrity, and preservation of TEK/Tie2 expression. These findings support nebulized hUC-MSC-EVs as a potential lung-targeted prophylactic strategy for hypobaric hypoxia-induced lung injury and suggest that ROS imbalance may be associated with Tie2 preservation. Full article

This study systematically investigated the combined effects of drying method (mid- and short-wave infrared drying, MSID; hot air drying, HAD; radio frequency-hot air combined drying, RF-HAD), drying temperature (35, 45, 55, 60 °C), and initial wet-basis moisture content (20%, 25%, 30%) on drying characteristics, nutritional quality, texture, and oxidative stability of peanuts. RF-HAD achieved the shortest drying time, followed by MSID and HAD. Protein content remained stable across all treatments. Fat, oleic acid, and total amino acids were significantly affected by all three factors with significant two-way interactions; linoleic acid exhibited significant method × moisture and three-way interactions. Hardness, adhesiveness, springiness, gumminess, and chewiness showed significant three-way interactions, indicating interdependent effects. All samples met national standards for acid value and peroxide value. MSID yielded the lowest acid value and peroxide value immediately after drying, suggesting better initial oxidative quality. Acid value was primarily influenced by method and temperature, with significant two-way interactions, whereas peroxide value showed significant main effects and a highly significant three-way interaction. No single drying condition optimized all quality attributes. RF-HAD excels in drying efficiency and texture enhancement but requires temperature control to limit oxidation; MSID offers superior initial oxidative stability and amino acid retention. Initial moisture content acts as an active variable that modulates the effects of drying method and temperature. Full article

Objective: This work aims to reduce the surface tension of an aluminum–silicon alloy melt by adding different amounts of the Zn element, thus improving the coatability and coating quality of hot-dip aluminum plating on steel plates. Method: Wetting experiments were conducted at 1023 K using a modified sessile drop method. Conclusions: The addition of the Zn element can reduce the surface tension of the Al-Si alloy, thus decreasing the wettability of the Al-Si alloy. Zn vapor can break down the surface oxide film to expose the fresh melt. The wettability of the Al-10Si alloy on interstitial-free (IF) steel and surface tension were investigated using the modified sessile drop method at 1023 K. Axisymmetric Drop Shape Analysis software was utilized to calculate the contact angles of the Al-10Si-xZn/Al₂O₃ and Al-10Si-xZn/IF steel systems (x ranges from 0 wt.% to 5 wt.%). Moreover, the microtopography and microstructure of surfaces and cross-sections were analyzed by means of an energy-dispersive spectrometer and scanning electron microscope. The results indicated that the surface tension of the alloy melt gradually decreases with an increase in Zn content, ranging from 874 to 760 mN/m. The contact angle of the Al-10Si-xZn alloy melt on IF steel also progressively decreases with increasing Zn content, which is attributed to the lower surface tension of Zn. This study also discovered that the Zn element can disrupt the oxide film of the Al-10Si alloy, exposing the fresh melt and thereby reducing the surface tension of the alloy liquid, thus enhancing wettability. The addition of Zn might be capable of improving the hot-dip aluminizing coatability of steel plates and the quality of the coating. Full article

Nanoparticle powders of a Ce_1−xRu_xO₂ mixed oxide (3.0% w/w), were synthesized to be used as catalytic supports, on which Pt and Ir nanoparticles were deposited as the active phase. The catalytic supports were prepared through a route involving microwave heating, while the Pt or Ir nanoparticles were incorporated via the wet incipient method. The {Pt, Ir/Ce_1−xRu_xO₂} catalytic systems were successfully tested as catalysts for low-temperature CO oxidation. To provide adequate support to our results, the compounds were characterized by SEM, EDS, XRD, DRS-UV-vis, and XPS techniques. In addition, BET isotherms were carried out to determine specific surface area features. The CO oxidation evolution was tested in the range of 25–350 °C. Both Pt and Ir supported Ce_1−xRu_xO₂ catalysts that remarkably improved the CO oxidation, reaching and sustaining 100% conversion from 125 °C onwards. Remarkably, the mixed oxide support, by itself, showed outstanding performance, achieving 100% conversion to CO₂, at a temperature of 225 °C. Full article

Background: Hepatic ischemia–reperfusion (I/R) injury induces systemic oxidative stress and inflammatory responses that may lead to remote lung injury. This study investigated whether taxifolin attenuates hepatic I/R-induced lung damage and examined the involvement of the nuclear factor-κB (NF-κB) and high-mobility group box-1 (HMGB1) signaling axis. Methods: Twenty-eight male Wistar rats were divided into four groups (n = 7): control, taxifolin, hepatic I/R, and taxifolin+I/R. Serum oxidative stress markers (malondialdehyde [MDA], interleukin [IL]-6, total antioxidant/oxidant status [TAS/TOS]) and wet-to-dry lung weight ratio were measured. Lung tissues were evaluated histopathologically and immunohistochemically for NF-κB and HMGB1 expression. Bioinformatics pathway enrichment and molecular docking analyses were also performed. Results: Hepatic I/R significantly increased serum MDA, IL-6, and TOS levels and decreased TAS (p < 0.05). Severe lung injury was observed in the hepatic I/R group (median score: 11), whereas taxifolin pretreatment significantly reduced the injury score (median score: 5, p < 0.001). NF-κB and HMGB1 expression were markedly elevated following hepatic I/R and significantly decreased with taxifolin treatment (p < 0.05). A strong positive correlation was found between NF-κB and HMGB1 expression (r = 0.82, p < 0.001). Pathway enrichment analysis indicated involvement of Toll-like receptor (TLR)-related inflammatory signaling, and docking analysis demonstrated favorable binding of taxifolin to TLR4 and NF-κB p65. Conclusion: Taxifolin attenuated hepatic I/R-induced lung injury by reducing oxidative stress and suppressing HMGB1–TLR4–NF-κB-mediated inflammatory signaling. Full article

Advanced oxidation technology utilizing ozone as the oxidant shows great potential for the efficient purification of wastewater. However, the efficiency of ozone decomposition remains a significant bottleneck limiting the performance of ozone-based advanced oxidation processes. Catalytic ozone decomposition technology is a highly effective approach to enhancing ozone utilization efficiency; nevertheless, the competing adsorption of water molecules results in low catalytic reaction efficiency and catalyst deactivation. In this study, NiFe layered double hydroxide (LDH) was prepared successfully through the hydrothermal method. In situ DRIFTS with isotope labeling revealed that ozone combines with surface H atoms to produce H₂O, whereas the oxidation of high-valence metals destroys H₂O, producing H atoms that return to the surface of NiFe LDH. The unique structure of NiFe LDH allows water to participate in the surface H atom cycle process, and the charge exchange between Ni and Fe atoms accelerates the recovery of surface H atoms, which avoids the deactivation of the active site caused by competitive adsorption of water molecules, achieving a catalytic ozone decomposition efficiency of 99% for 80 h and 59.0% for simulated wastewater containing polyacrylamide as a model pollutant. This work presents a fresh insight into surface H cycling of LDH materials to improve the wet resistance of the catalysts. Full article

Nickel-supported catalysts over SiO₂-CeO₂ mixed oxides were investigated as catalysts for syngas production via dry reforming of methane. SiO₂-CeO₂ supports were optimized by varying the preparation method and ceria loading with the aim of stabilizing nickel nanoparticles, enhancing the catalytic performance, and improving the resistance to coke formation under high-temperature reforming conditions. To investigate the effect of support composition, SiO₂-CeO₂ mixed oxides with ceria contents ranging from 5 to 30 wt% were prepared using two synthesis routes: sol–gel and wetness impregnation methods. A nickel loading of 5 wt% was deposited on the resulting supports. The catalysts were characterized by XRD, N₂ physisorption, temperature-programmed reduction (TPR), and Raman spectroscopy. Catalytic activity tests were carried out over reduced catalysts in an H₂-He stream at 750 °C, using a feed mixture containing 15 vol% CH₄ and 15 vol% CO₂ in He. The effect of temperature on catalytic performance was evaluated in the range of 450–750 °C. Thermogravimetric, XRD and Raman analyses of spent catalysts were used to assess carbon deposition and the nature of crystalline phases. The results highlight the role of CeO₂ content and preparation method in determining nickel dispersion, reducibility, catalytic performance in DRM, and coke resistance. Full article

Welding copper (Cu) and aluminum (Al) is highly demanded for lightweight and cost-effective manufacturing. However, it faces significant challenges. First, substantial differences in physical properties may lead to high residual stresses and distortion. Second, brittle intermetallic compounds (IMCs) readily form at the interface, severely compromising the joint’s mechanical properties and electrical conductivity. Third, the native oxide film on Al impedes effective wetting and bonding. Therefore, effective control over the interfacial microstructure of the welded joint is essential. This review provides a critical analysis and comparison of several typical welding techniques, including laser welding (LW), friction stir welding (FSW), ultrasonic welding (UW), brazing and soldering, and welding–brazing. These analyses focus on their process characteristics, joint microstructures, and corresponding formation mechanisms. Furthermore, this review synthesizes key strategies for enhancing joint quality, including process parameter optimization, introduction of functional interlayers, and external assistance, aimed at optimizing joint microstructure and minimizing defects. Based on the analysis, this work provides comparative insights into process selection and microstructure control, and highlights future directions: advancing novel methods such as magnetic pulse welding and transient liquid phase bonding; developing intelligent real-time process control to suppress brittle IMCs and associated defects; promoting sustainable practices and establishing standardized performance evaluation; and systematically investigating long-term reliability to support the industrial application of robust Cu/Al joints. Full article

Recycled carbon fibres frequently exhibit degraded surface functionality owing to prior matrix removal processes, limiting their compatibility with contemporary epoxy resin systems. This study proposes a nanobubble-based surface treatment route designed to restore and enhance the surface characteristics of recycled carbon fibres without aggressive chemical oxidation. The study generated ozone and carbon dioxide nanobubbles in aqueous media and experimentally investigated the effects of nanobubble treatment on the surface properties and adhesive behaviour of recycled carbon fibres. Surface chemical changes were examined using X-ray photoelectron spectroscopy, which revealed an increase in oxygen-containing functional groups due to the nanobubble treatment, indicating improved surface polarity and potential for chemical interaction with epoxy networks. The practical effectiveness of the treatment was assessed via a pinhole pull-out test that served as an indirect measure of interfacial adhesion with epoxy resin, especially the combination of ozone nanobubbles and recycled carbon fibres. Notably, the nanobubble-treated recycled carbon fibres exhibited an increase in the adhesion compared with untreated recycled carbon fibres, rising from 84.5 ± 11.5 MPa to 138.5 ± 14.8 MPa, reflecting enhanced wetting behaviour and stronger fibre–matrix interfacial bonding. Overall, the proposed nanobubble processing route offers a mild, scalable, and environmentally favourable method for restoring surface reactivity in recycled carbon fibres, supporting their reintegration into high-performance composite applications. Full article

Porous silicon (PSi), characterized by its high specific surface area and highly tunable morphology, presents significant potential across optoelectronics, energy storage, and biomedical applications. This review provides a systematic analysis of the synthesis methodologies, interfacial chemical engineering, and diverse applications of PSi. Initially, fabrication techniques are examined, contrasting the pore formation mechanisms of electrochemical anodization, metal-assisted chemical etching (MACE), and emerging vapor-phase etching methods, while elucidating the control of geometric parameters from microporous to macroporous scales. To address the thermodynamic instability of the hydride-terminated surface, this review systematically evaluates modification strategies such as thermal oxidation, hydrosilylation, carbonization, and atomic layer deposition (ALD). We critically analyze their efficacy in mitigating oxidative drift and enabling specific functionalization. Subsequently, the review summarizes current applications in sensing (refractive index and photoluminescence modulation), energy storage (lithium-ion battery anodes and supercapacitors), and microsystem technologies (radio frequency (RF) isolation, gettering, and micro-electro-mechanical systems (MEMS) sacrificial layers), emphasizing the critical role of structure–property relationships. Finally, an objective assessment is provided regarding the challenges in translating PSi technology to industrial scales, specifically addressing the trade-offs between biodegradability and stability, wafer-scale process uniformity, and the compatibility of wet-chemical processing with standard complementary metal–oxide–semiconductor (CMOS) integration flows. Full article

Sewage sludge management is a major challenge in modern wastewater treatment, as sludge contains organic matter, nutrients, pathogens, heavy metals, and emerging contaminants. Increasing wastewater volumes from urbanization and population growth have led to steadily rising global sludge production, emphasizing the need for sustainable and resource-efficient treatment strategies. Conventional methods—such as landfilling, land application, and biological treatment—face limitations due to contaminant risks, regulatory restrictions, and incomplete pollutant removal. Thermal and thermochemical processes offer substantial volume reduction, energy recovery, and resource valorization. Incineration is widely implemented and ensures complete oxidation but requires high energy input and emission control. Gasification and pyrolysis produce syngas, bio-oil, and biochar, supporting circular economy applications, while hydrothermal carbonization (HTC) efficiently converts wet sludge into hydrochar without intensive drying. This study presents a comparative life cycle assessment (LCA) and mass–energy assessment of these four thermal treatment methods, highlighting their environmental impacts, energy efficiencies, and resources’ recovery potential to support more sustainable sludge management. Full article

Selective laser sintering (SLS) is an additive manufacturing method that enables the creation of complex-shaped polymer-based structures with great control over the desired properties. In this study, polyamide 12 (PA12)–based powders containing 0.8 wt.% graphene oxide (GO), introduced via a wet-mixing impregnation method, were processed by selective laser sintering (SLS). Implementation of a double laser scanning strategy increased the tensile strength of the composites by 2.5% relative to pristine SLS-processed PA12 and enhanced the thermal conductivity to 0.74 W·m⁻¹·K⁻¹. The results indicate that the laser sintering process is an effective approach to produce low filler content polymer-matrix composites with enhanced thermal properties while preserving mechanical integrity and maintaining electrical insulation behavior. Full article

Rice is a vital staple food crop worldwide and also one of the major sources of greenhouse gas (GHG) emissions, generating substantial methane (CH₄) and nitrous oxide (N₂O). As one of the key management practices for rice production, the GHG mitigation potential of water management has attracted extensive attention, whereas its global scalability remains to be further investigated. Based on 15,458 global observations of field experimental data, we employed advanced machine learning methods to quantify the GHGs and soil carbon sequestration of global rice systems around 2020. Furthermore, we identified the optimal spatial distribution of GHG mitigation for five rice water management practices (continuous flooding (CF), flooding–midseason drainage–reflooding (FDF), alternate wetting and drying irrigation (AWD), flooding–midseason drainage–intermittent irrigation (FDI), and rainfed cultivation (RF)) through scenario simulation, under the premise of no yield reduction. The results of machine learning simulation showed that optimizing water management could reduce global rice greenhouse gas emissions by 39.17%, equivalent to 340.46 Mt CO₂ eq, while increasing rice yields by 3.55%. This study provides valuable insights for the optimization of agricultural infrastructure and the realization of agricultural sustainable development. Full article