Both ˙OH and CO ₃ ˙ ⁻ participated in the degradation of BPA in the nZVI/SPC system, and ˙OH was the main radical.

In this study, the zero-valent iron Fenton reagent (ZVI Fenton-like) system was combined with the chemical precipitation method for the deep treatment of desulfurization wastewater from coal-fired power plants, and the chemical oxygen demand (COD) was used as the evaluation criterion for organic matter in the desulfurization wastewater. The effects of reaction time, H₂O₂ dosage, zero-valent iron dosage, pH, and reaction temperature were also investigated. The results showed that the COD concentration of the effluent was the lowest when the running time of the ZVI Fenton-like reagent system was 1 h, the dosage of H₂O₂ was 33.3 mg·L⁻¹, the dosage of iron was 0.075 g·L⁻¹, the pH was 4.5~6.5, the reaction temperature was 35 °C, the COD concentration of the wastewater was the lowest and its operating conditions were the best, and the internal reaction mechanism was finally deduced. In summary, the zero-valent iron Fenton reagent system provides a new idea for the treatment of desulfurization wastewater from coal-fired power plants.

Aluminum (Al) toxicity is the primary factor limiting agricultural productivity in acid soils. The cell wall is mainly composed of saccharides and the first barrier for aluminum (Al) to enter plant root cells, but it is unknown whether and how root saccharide components are involved in regulating the Al tolerance of Lespedeza that is well adapted to acid soils. Here, we used Al-tolerant Lespedeza bicolor and Al-sensitive Lespedeza cuneata to examine the association of root saccharide components with Lespedeza Al tolerance through analyzing the saccharide changes of roots exposed to Al toxicity. Al-sensitive Lespedeza accumulated more Al and pectin but less hemicellulose in the root cell walls than Al-tolerant Lespedeza. Al treatment decreased the amounts of total sugar secreted from and within the roots of only Al-tolerant Lespedeza. Al treatment decreased the content of root monosaccharides including glucose and mannose in both Lespedeza species, but increased the xylose contents in only Al-sensitive Lespedeza. Taken together, less cell wall pectin rather than hemicellulose is responsible for less root Al accumulation, and Al-decreased root saccharide contents may enhance root organic-acid secretion to chelate toxic Al, both of which contribute to Lespedeza Al tolerance.

Urban CO₂ marginal abatement costs (MACs) provide important information for designing sustainable low-carbon transition strategies, but their interpretation may be affected by reference technology choices and identification uncertainty. Using 5004 city-year observations from 278 Chinese prefecture-level cities over 2006–2023, this study applies a Global non-radial directional distance function to compare National and four-region Group reference technologies under identical baseline settings. At each fixed frontier projection, we characterize the complete admissible range of supporting shadow prices rather than select a single dual solution and assess sensitivity across seven prespecified modeling dimensions. Under the National benchmark, 87.31% of observations are bounded-set identified. National and Group identified sets overlap in 74.34% of city-years, indicating that strict benchmark ordering is uncommon. Across baseline–alternative comparisons, identification status changes in 9.87% of cases, whereas National–Group direction reversals occur in 0.84%; temporal technology generates the largest identification response (25.92%). Baseline numerical diagnostics show successful primal–dual solutions, unique projections, and no nesting violations. The results support more transparent sustainability-oriented assessments of urban decarbonization by reporting MACs together with identification status, benchmark choice, and specification sensitivity rather than as unconditional scalar values.