Journal of Fuel Chemistry and Technology•2026•DOI: 10.1016/S1872-5813(25)60631-1
Methane dehydroaromatization (MDA) offers a carbon-neutral route to benzene, toluene, and xylene (BTX), yet the regulatory mechanisms of Brønsted acid site (BAS) strength and spatial proximity to Mo sites remain unresolved. This study systematically tunes BAS strength via isomorphous substitution (Al, Ga, Fe, B) and Mo-BAS proximity in ZSM-5, integrating catalytic evaluations with density functional theory (DFT). Strongly acidic Al-zeolites achieve the highest methane conversion, while weakly acidic B-substituted systems exhibit optimal mono-/bifunctional synergy, outperforming moderate-acid counterparts. DFT reveals that deprotonation energy (DPE) correlates with acid strength; Al-ZSM-5 (DPE = -5.68 eV) lowers the C–H activation barrier (ΔG = 1.467 eV). Spatial proximity analysis shows that nanoscale Mo-BAS distances, achieved via ball milling, enhance methane conversion by 33% and BTX yield by 31% compared to micrometer-scale mixtures, by accelerating intermediate transport and suppressing coke. These findings establish a multi-scale framework linking acid strength, spatial confinement, and electronic modulation, providing actionable guidelines for designing next-generation MDA catalysts.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202605010
The underwater light environment is a critical limiting factor for the colonization of submerged macrophytes and the ecological restoration of shallow lakes. Previous studies rarely quantified the contribution of aquatic environmental factors to the water quality–underwater light–macrophyte relationship, nor did they comprehensively consider factor correlations or establish thresholds for macrophyte colonization. This study, conducted in a typical national wetland nature reserve (Hongze Lake), measured photosynthetically active radiation, light attenuation coefficient (Kd), euphotic depth (Zeu), water transparency (SD), total suspended solids (TSS), chlorophyll-a (Chl-a), total nitrogen (TN), and total phosphorus (TP). A simulation model for Kd was developed, spatial distributions of environmental factors were analyzed, and contribution rates to light attenuation were quantified. Results showed that the mean Kd was 10.31±3.76 m⁻¹, and the mean Zeu (0.53±0.24 m) was lower than the mean water depth (0.94±0.29 m), with a spatial pattern of shallower Zeu in the west and deeper in the east. TSS and Chl-a were the primary direct influencing factors, while TN acted mainly indirectly. To achieve effective macrophyte colonization under average water depth conditions, thresholds were determined: Zeu ≥ 0.94 m, SD ≥ 0.41 m, Kd ≤ 4.95 m⁻¹, and Chl-a ≤ 3.8 μg/L. These findings provide quantitative guidance for lake restoration and water quality management.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202605009
Reservoir CO2 emissions are a critical component of the global carbon cycle, yet existing prediction models often neglect reservoir size stratification, mixing data from large, medium, and small reservoirs. This study addresses this gap by constructing a training dataset exclusively for large and medium reservoirs in China and developing a neural network-based CO2 flux prediction model. The model revealed significant latitudinal zonation, with CO2 fluxes in southern low-latitude basins (e.g., Yangtze, Pearl) substantially higher than in northern high-latitude basins (e.g., Yellow, Songliao). Statistical analysis identified total phosphorus (TP) content as the strongest driver, exhibiting a positive exponential correlation with CO2 flux (p < 0.01). Reservoir age and latitude showed significant negative correlations, while physical parameters such as reservoir area, pre-impoundment submersion ratio, and average water depth showed no significant national-scale correlation. The study underscores the heterogeneity of dominant drivers across basins and proposes differentiated carbon mitigation strategies: for southern high-emission basins, controlling phosphorus inputs through wastewater treatment and restricting aquaculture; for northern basins, enhancing soil conservation to reduce carbon-rich sediment influx; and for new reservoirs, implementing vegetation clearance before impoundment and optimizing flood discharge schedules. These findings provide a theoretical basis for carbon emission characterization and support low-carbon management of large and medium reservoirs in China.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3926-0
Chirality is a fundamental determinant of molecular recognition and biological function, yet its integration into inorganic clusters remains a formidable challenge. Polyoxometalates (POMs), characterized by atomic precision, structural tunability, and versatile redox properties, provide an exceptional platform for investigating chirality at the interface of inorganic chemistry and biomedicine. Over the past two decades, substantial progress has been made in constructing chiral POM-based materials through diverse strategies, including chirality induction by external environments, intrinsic structural chirality, spontaneous symmetry breaking, and the design of self-assembled supramolecular architectures. The distinctive combination of redox activity, stability, and chirality in these systems has unlocked new avenues for biomedical applications, spanning antibacterial and anticancer therapies to potential interventions in neurodegenerative disorders. This review comprehensively overviews recent advances in the synthesis and biomedical applications of chiral POM-based materials, while outlining key challenges and opportunities that will guide future research in this emerging field.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2026022702
This study systematically investigated the occurrence and vertical distribution of per- and polyfluoroalkyl substances (PFAS) in solid waste, leachate, and surrounding groundwater at a municipal solid waste landfill in Fuyang City, Anhui Province, China. A total of 23 PFAS were detected in solid waste, with total concentrations (∑PFAS) ranging from 7.95 to 172.28 ng·g⁻¹. Trifluoroacetic acid (TFA), an ultrashort-chain PFAS, was ubiquitous, contributing on average 59% to the total PFAS mass. PFAS composition varied with depth: long-chain PFAS dominated in middle and upper layers, while short-chain and ultrashort-chain PFAS were more abundant in deeper layers, indicating enhanced downward migration of shorter-chain compounds. Sulfonic acid PFAS exhibited increasing relative abundance with depth. Leachate ∑PFAS concentration was 14.35 μg·L⁻¹, dominated by short-chain compounds such as PFPrS and PFBS, consistent with the composition in bottom-layer waste. Groundwater surrounding the landfill contained multiple PFAS, with concentrations decreasing with distance from the landfill, confirming the landfill as a source of PFAS to the surrounding environment. Multivariate analyses (PCoA and Bray–Curtis dissimilarity) revealed that some groundwater samples closely resembled leachate in PFAS composition, suggesting direct impact via leachate migration. These findings underscore the role of landfills as significant reservoirs and sources of PFAS, particularly ultrashort-chain compounds, and highlight the need for improved leachate management to mitigate groundwater contamination.