RSC Advances最新文献

The widespread application of pesticides in modern agriculture has significantly boosted crop production; however, their inherent toxicity, persistence, and resistance to conventional cleanup methods have led to serious environmental and public health concerns. Advanced oxidation processes (AOP), especially those utilizing visible light for photocatalysis, have recently emerged as promising eco-friendly alternatives for the degradation of pesticides. In particular, zinc oxide (ZnO) based nanophotocatalysts have garnered considerable attention due to their wide band gap (∼3.37 eV), strong oxidative capability, high electron mobility, low electron–hole recombination rates, and natural antibacterial properties, which enhance their photocatalytic activity under sunlight. This review provides a comprehensive overview of recent progress in ZnO-mediated photocatalytic degradation of pesticides, focusing on synthesis methods, structural modifications such as doping and defect engineering, and material hybridization aimed at improving photocatalytic efficiency. Furthermore, the study critically examines the influence of key factors, including catalyst concentration, surface morphology, and particle size, on degradation performance. This review aims to offer a thorough understanding of the versatility of ZnO as a tunable photocatalyst for mitigating pesticide contamination in wastewater by combining mechanistic insights with experimental observations. This integration not only highlights the potential of ZnO in this context but also establishes a foundation for creating scalable and eco-friendly remediation approaches.

This study investigates the degradation state of silicone rubber (SiR) under electric and thermal fields by analyzing its gas-evolution characteristics. The goal is to provide a new diagnostic approach for high-voltage cable accessories. Thermogravimetry-infrared spectroscopy (TG-IR) was used to trace the thermal decomposition products. Electrical breakdown was simulated through discharge experiments. Density functional theory (DFT) calculations and reactive force field (ReaxFF) molecular dynamics simulations were employed to verify the reaction mechanisms and decomposition pathways. The results show that under electric field, SiR mainly produces CH₄, C₂H₂, and silane (SiH₄), accompanied by CO and CO₂. Under thermal field, the main products are CH₂O, CH₄, hexamethylcyclotrisiloxane (D3), and octamethylcyclotetrasiloxane (D4), along with oxidative gases such as CO₂. Molecular simulations revealed differences in microscopic decomposition pathways. A normalized infrared spectral database was also established based on DFT calculations. Overall, this work links macroscopic gas-evolution behavior with microscopic mechanisms and diagnostic applications. It systematically elucidates the decomposition behavior of SiR under electric and thermal fields and provides a theoretical foundation for gas-infrared-based fault diagnosis in cable accessories.

The growing demand for high-performance electromagnetic (EM) absorbers and interference (EMI) shielding materials has motivated the design of structurally tunable ferrites with balanced dielectric and magnetic losses. In this study, crystalline Ba_0.5Sr_0.5Y_1.0Fe_11−x(Co_x/2Al_x/2)O₁₉ (x = 0.00–1.00) hexaferrites were synthesized via a sol–gel auto-combustion route to investigate the correlation between multi-cation substitution, microstructure, and microwave absorption. Rietveld-refined X-ray diffraction confirmed single-phase M-type hexagonal symmetry (P6₃/mmc) with systematic lattice contraction from 693.53 ų (x = 0.0) to 671.27 ų (x = 1.0) due to smaller Co²⁺ and Al³⁺ ionic radii. Field emission scanning electron microscopy and energy-dispersive X-ray analyses revealed dense, homogeneous microstructures with uniform dopant distribution. Magnetic measurements showed a progressive softening with substitution saturation magnetization (M_s) decreased from 54.79 emu g⁻¹ (x = 0.0) to 41.80 emu g⁻¹ (x = 1.0), while coercivity (H_c) dropped from 1788.8 Oe to 77.7 Oe attributed to dilution of Fe³⁺–O–Fe³⁺ superexchange and reduced anisotropy constant (K₁ ≈ 10⁵ to 10³ erg cm⁻³). The optimized composition, x = 0.50, achieved outstanding microwave absorption with a minimum reflection loss (RL_min) of −47.58 dB at 9.27 GHz (6 mm thickness) and an effective absorption bandwidth of 0.609 GHz, confirming nearly complete EM attenuation. Dielectric and magnetic spectra revealed that balanced permittivity (ε′, ε″) and permeability (µ′, µ″) ensured impedance matching (Z_in ≈ Z₀), while enhanced attenuation constant (α) and reduced eddy current loss promoted multi-mechanistic energy dissipation. These findings demonstrate that Co–Al co-substitution effectively tailors lattice strain, anisotropy, and interfacial polarization, providing a rational design strategy for high-efficiency microwave absorbers and EMI-shielding hexaferrites in the X-band region.

The blending proportion of cut tobacco significantly affects the intrinsic quality of the cigarette product. Variability in the moisture content of cut tobacco markedly influences its near-infrared (NIR) spectral signature and the accuracy of blending proportion prediction models. To address this critical challenge, spectral data were systematically collected from tobacco samples at various moisture levels. Four partial least squares regression (PLSR)-based correction methods were implemented to mitigate the moisture effect: global correction, orthogonal signal correction (OSC), generalized least squares weighting (GLSW), and dynamic orthogonal projection (DOP). The results indicate that moisture content strongly influences the diffuse transmission spectrum of cut tobacco. A model calibrated at a fixed 12.15% moisture content achieves satisfactory prediction accuracy under that specific condition but exhibits substantial errors when applied to samples with different moisture levels. This underscores the necessity of correcting for moisture effects to establish a more robust and generalizable blending proportion prediction model. Among the correction methods, DOP yielded the most promising performance, enhancing the coefficient of determination for prediction (R_p) from 0.39 to 0.90 and decreasing the root mean square error of prediction (RMSEP) from 5.50% to 2.22% compared to the uncorrected model. These findings have significant practical implications for advancing the application of blending proportion prediction in the tobacco industry.

Chronic diabetic wounds are notoriously difficult to heal due to a hyperglycemic environment, persistent oxidative stress, and infection, leading to slow healing and frequent complications. In this study, we developed a tri-layer intelligent hydrogel dressing for diabetic wound care. The top layer contains silver nanoparticles (AgNPs) for rapid initial antibacterial action. The middle layer incorporates poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with mangiferin to achieve sustained drug release and promote angiogenesis. The bottom layer is a gelatin methacryloyl (GelMA) hydrogel scaffold that provides structural support. The composite materials' morphology and structure were characterized by scanning and transmission electron microscopy (SEM, TEM). We evaluated the properties of hydrogel contain mechanical properties, degradation and swelling behaviors, drug release profiles, antibacterial and antibiofilm effects, and cell-related biological properties. The results showed that the tri-layer hydrogel exhibited higher mechanical strength and greater degradation stability than a homogeneous GelMA hydrogel. The layered structure of hydrogel effectively delayed the release of mangiferin, resulting in a significantly lower cumulative release over 72 hours compared to a non-layered control. Antibacterial tests demonstrated that the tri-layer hydrogel produced the largest inhibition zones and the highest bacterial-killing rates against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), and it markedly inhibited the formation of bacterial biofilms. In vitro, cell studies showed that the tri-layer hydrogel significantly downregulated the pro-inflammatory cytokines IL-6 and TNF-α, upregulated the anti-inflammatory cytokine IL-10, and substantially reduced intracellular reactive oxygen species (ROS) accumulation. In summary, the tri-layer intelligent hydrogel dressing, through its synergistic controlled-release and antibacterial mechanisms, offers an effective multi-factorial intervention strategy for the treatment of chronic diabetic wounds.

The O₃-initiated degradation mechanisms of trifluoropropene (CF₃CHCH₂) were studied using density functional theory (DFT). Three types of mechanisms were observed for the title reaction, namely, addition/elimination, H-abstraction and substitution. The computations showed that O₃ with a CC bond undergoes a 1,3-cycloaddition reaction to generate a primary ozone intermediate (POZ) with a relatively low free energy barrier, which then dissociates to generate an aldehyde group and carbonyl oxide, known as Criegee intermediates (CIs). Detailed analysis was conducted on the subsequent reactions of CIs. It is found that when a new type of CI-containing halogenated alkyl groups reacts with NO, NO₂, CH₂O, SO₂, H₂O and O₂, its reaction pathway is singularly analogous to that of the general CI. The degradation total rate coefficient and the estimated lifetime are in accordance with the experimental results. The current calculation results are of great significance for the atmospheric chemistry of the ozone oxidation of unsaturated halogenated compounds.

Persistent organic pollutants pose significant long-term risks to environmental and human health due to their carcinogenic, mutagenic, and teratogenic properties. This study focuses on the efficient activation of peroxymonosulfate (PMS) through the rational design of a cobalt-based metal–organic framework (ZIF-67) catalyst, enabling rapid degradation of high-concentration dye pollutants. By optimizing the molar ratio of 2-methylimidazole (2-MeIM) to Co(NO₃)₂·6H₂O and employing a hydrothermal synthesis method, we fabricated ZIF-67 (4 : 1) with high crystallinity, large specific surface area (1656.68 m² g⁻¹), and stable degradation performance. The ZIF-67 (4 : 1)/PMS system achieved complete degradation of 20 mg L⁻¹ and 100 mg per L Rhodamine B (RhB) within 60 seconds and 6 minutes, respectively, surpassing recent reported efficiencies. The system also maintained high activity over a broad pH range (3–9). Radical quenching experiments and electron paramagnetic resonance (EPR) analysis identified sulfate radicals (˙SO₄⁻₄) and singlet oxygen (¹O₂) as the dominant reactive species. Furthermore, the catalyst exhibited excellent recyclability with no significant loss in activity after five consecutive cycles. This work provides a facile and scalable strategy for preparing highly active cobalt-based catalysts, demonstrating great potential for practical applications in industrial wastewater treatment and environmental remediation.

Systemically tailored cerium-doped Bi₃YO₆/rGO ceramic nanohybrids were prepared by a sequential hydrothermal-ultrasonication approach to surmount the innate limitations of binary metal oxides in visible-light photocatalysis, such as limited spectral absorption and fast electron–hole recombination. Incorporation of rare earths (Ce³⁺/Ce⁴⁺) into the Bi₃YO₆ lattice introduces defect-assisted carrier trapping and local band structure reconfiguration, while conductive wrapping with rGO forms an interconnected network of charge transport, enabling spatial electron migration and thus recombination suppression. Comprehensive physicochemical characterization by XRD, FTIR, TGA, and SEM; optical studies (UV-vis, PL); and electrical/electrochemical analyses (I–V, EIS, transient photocurrent) evidenced crystalline cubic Bi₃YO₆ with a flake-like morphology, a narrowed bandgap from 2.74 to 2.56 eV, superior light harvesting capability, and reduced interfacial resistance in the hybrid photocatalyst compared with its pristine counterpart. Under visible-light irradiation (λ > 420 nm), the optimized Ce–Bi₃YO₆/rGO displayed excellent photocatalytic activity toward crystal violet degradation, yielding 92.04% removal (k = 0.0800 min⁻¹), significantly higher than those of Ce–Bi₃YO₆ (76.28%) and Bi₃YO₆ (62.37%). Scavenger experiments confirmed that ˙OH and ˙O₂⁻ species dominated the oxidative pathways, further confirming the proposed radical-driven mechanism facilitated by rGO-directed electron extraction. The catalyst showed strong reusability, with efficiency retention of >84% after five cycles, thus confirming outstanding structural robustness and photochemical durability. This work develops a synergistic approach that involves defect engineering and carbon-framework incorporation to further advance Bi-based ceramic photocatalysts toward a scalable and high-performance platform for visible-light-driven wastewater remediation.

Brown grease (BG), a high free-fatty-acid rendering coproduct, was upgraded to lubricant base stocks via one of four single-step functionalization methods: ethyl esterification, methyl esterification, epoxidation, or hydroxylation to give FAEEc/b, FAMEc/b, Epoxy BGc/b, or Hydro BGc/b, respectively (from crude, c, or bleached, b, BG). Each modification was carried out on crude and degummed/bleached brown grease, and the ten materials were evaluated by thermogravimetric analysis (T_d,5%), dynamic (µ) and kinematic (ν) viscosities at 40 and 100 °C, density, viscosity index (VI), and pour point, then mapped to ISO VG grades. Clear structure–property trends emerge. Esterification lowers ν₄₀ and improves temperature-thinning (FAEEb: ν₄₀ = 9.33 mm² s⁻¹, VI = 199, pour point = 0 °C; ISO VG 10). Hydroxylation raises ν₄₀ into mid-grade ranges (Hydro BGc: ν₄₀ = 98.4 mm² s⁻¹, ν₁₀₀ = 12.5 mm² s⁻¹, VI = 121; ISO VG 100) and delivers the highest thermal onset (T_d,5% = 234 °C), but with poor cold-flow (pour point = 28 °C). Epoxidation affords very high viscosities (ν₄₀ = 1.5–1.7 × 10³ mm² s⁻¹, VI = 30–40), best suited as thickeners rather than neat base stocks. Parent greases fall near ISO VG 32 (ν₄₀ = 34–38 mm² s⁻¹) with pour points of 28–31 °C. These proof-of-concept results delineate application-relevant niches (high-VI light esters; VG 100 hydroxy-oils) and demonstrate a route to valorise non-edible fats into bio-derived lubricants.

Indirubin, an active component of the traditional Chinese medicine Indigo Naturalis, has drawn significant attention owing to its remarkable anti-leukemia activity. Nevertheless, it presents issues such as limited natural resources, poor solubility, and potential toxicity, which impede its clinical application. In recent years, within the research realm of indirubins, the efficient synthetic strategies and the exploration in the treatment of leukemia have remained the central research focuses in this field. This article comprehensively reviews the research advancements of indirubin derivatives in synthesis strategies and anti-leukemia effects since 2010s. Firstly, in this review, the synthetic methods of indirubin derivatives are categorized into two main types: chemical synthesis and bio & biomimetic synthesis. Among these, chemical methods assume a dominant position. These chemical synthesis approaches encompass acid-catalyze, organophosphorus-catalyzed, metal-catalyzed reactions, and one-step reduction reactions using KBH4. Secondly, based on the modification sites within the structure of indirubin, this paper undertakes a classified review of its derivatives and further delves deeply into the anti-leukemia activities of these derivatives. Additionally, we also discuss the future development directions of synthesizing indirubin derivatives and explore their structure–activity relationships in the context of anti-leukemia research. We firmly believe that this review can offer information support for scientific researchers engaged in the study of indirubin's anti-leukemia effects, thereby facilitating in-depth development.