Activation of peroxydisulfate by zero valent iron-carbon composites prepared by carbothermal reduction: Enhanced non-radical and radical synergies.

Since its application in environmental remediation, nano zero-valent iron (nZVI) has gained wide attention for its environmental friendliness, strong reducing ability, and wide range of raw materials. However, its high preparation cost and difficulty in preservation remain the bottlenecks for their application. Carbothermal reduction is a promising method for the industrial preparation of nZVI. Micronized zero-valent iron/carbon materials (Fe0/CB) were produced in one step by co-pyrolysis of carbon and iron. The performance of the Fe0/CB is comparable to that of nZVI. In addition, Fe0/CB overcomed the disadvantages of agglomeration and oxidative deactivation of nZVI. Experiments on the Fenton-like reaction of its activated PDS showed that metronidazole (MNZ) was efficiently removed through the synergistic action of radicals and non-radicals, which were mainly superoxide radicals (·O2-), monoclinic oxygen (1O2), and high-valent iron (FeIVO). Moreover, the degradation process showed better generalization, making it suitable for a wide range of applications in the degradation of antibiotics.

Study on the Spatiotemporal Evolution and Influencing Factors of Agricultural Carbon Emissions in the Counties of Zhejiang Province.

The accurate measurement of agricultural carbon emissions and the analysis of the key influential factors and spatial effects are the premise of the rational formulation of agricultural emission reduction policies and the promotion of the regional coordinated governance of reductions in agricultural carbon emissions. In this paper, a spatial autocorrelation model and spatial Dubin model are used to explore the spatiotemporal characteristics, influential factors and spatial effects of agricultural carbon emissions (ACEs). The results show that (1) From 2014 to 2019, the overall carbon emissions of Zhejiang Province showed a downward trend, while the agricultural carbon emission density showed an upward trend. ACEs are mainly caused by rice planting and land management, accounting for 59.08% and 26.17% of the total agricultural carbon emissions, respectively. (2) The ACEs in Zhejiang Province have an obvious spatial autocorrelation. The spatial clustering characteristics of the ACEs are enhanced, and the "H-H" cluster is mainly concentrated in the northeast of Zhejiang, while the "L-L" cluster is concentrated in the southwest. (3) The results of the Dubin model analysis across the whole sample area show that the ACEs exhibit a significant spatial spillover effect. The disposable income per capita in the rural areas of the county significantly promotes the increase in the ACEs in the neighboring counties, and the adjustment of the industrial structure of the county has a positive effect on the agricultural carbon emission reductions in neighboring counties. (4) The grouping results show that there is heterogeneity between 26 counties in the mountainous areas and non-mountainous areas. In the 26 mountainous counties, the urbanization rate, rural population, mechanization level and industrial structure have significant negative spatial spillover effects on the carbon emissions. In the non-mountainous counties, the agricultural economic development level and disposable income per capita of the rural residents have significant spatial spillover effects on the agricultural carbon emissions. These research results can provide a theoretical basis for the promotion of the development of low-carbon agriculture in Zhejiang according to the region and category.