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The catalysis of HRP coupling with redox mediator was a feasible technology for the transformation of antibiotics. This work screened three effective redox mediators syringaldehyde (SYR), acetosyringone (AS) and p-coumaric acid (PCA) for the norfloxacin (NOR) transformation in HRP/redox mediator system. Then, compared their transformation characteristics under varying conditions. The molecular docking results indicated HRP catalytic mediator was spontaneous, and the absolute value order of free energy between three redox mediators and HRP was consistent with the order of NOR removal in experiment. The presence of humic acid (HA) and polystyrene (PS) microplastics could block the removal of NOR, and the inhibition effect was proportional to the level of HA and PS particles. Seven and six possible intermediate products were identified by using SYR/AS and PCA as redox mediators, respectively, and potential NOR transformation pathways were proposed. SYR and AS treatment had the same transformation products and pathways due to their similar structure, including defluorination, oxidation, cross-coupled with mediator, demethylation and dehydrogenation. While for the PCA group, NOR not only performed the above action (except defluorination), but also underwent decarbonylation. These findings may expand our knowledge of the conversion and fate of fluoroquinolones through HRP coupled with redox mediator in the environment.

Microplastic is a new type of pollutant, which can act as a carrier for organic contaminants. It affects the migration and bioavailability of chemicals and potentially threatens the ecology. This work investigated the adsorption kinetics, isotherm and influencing factors of 17β-estradiol (E2) on three dominate microplastics. Then, used molecular dynamics (MD) simulation to analyze the adsorption mechanism. The results showed that E2 adsorption onto microplastics conformed well to the Pseudo-second-order kinetics and Redlich-Petersen isotherm model. The adsorption capacity of E2 on microplastics was polyethylene (PE)polypropylene (PP)polystyrene (PS). The small particle size of microplastics was conducive to the adsorption due to its large specific surface area. The thermodynamic parameters demonstrated the adsorption of E2 was a spontaneous and exothermic process, so low temperature was benefit for the adsorption. The MD simulation results indicated the adsorption of E2 on MPs belonged to surface adsorption. The order of E2 adsorption energy by three microplastics obtained by molecular dynamics simulation is consistent with the experimental results. This work may help to understand the molecular adsorption process and provide a theoretical basis for the combined ecotoxicity of microplastics.

Aquatic vegetation is an important component and main primary producer of lake ecosystems and plays an important role in improving water quality and maintaining biodiversity, which is critical to diagnosing the health of aquatic ecosystems in shallow lakes. It is therefore important to accurately obtain information on dynamic changes and spatial-temporal distribution of aquatic vegetation. Based on the Sentinel-2 satellite remote sensing images from 2016–2022, we studied the feasibility of using remote sensing technology to monitor the spatial-temporal changes of aquatic vegetation before and after the removal of the fence, taking Futou Lake in Hubei Province as a case study. Two vegetation indices, Normalized Difference Vegetation Index (NDVI) and Submerged Aquatic Vegetation Index (SAVI) were applied to identify the open water and the aquatic vegetation through two threshold determination methods, Otsu algorithm and manual division threshold method. The results show that: (1) the classification based on the NDVI and manual division threshold method performs the best, with the overall classification accuracy of 94.44% and the Kappa coefficient of 85.23%. (2) The growth of aquatic vegetation is divided into stages, the first stage is enclosing culture, and the distribution of aquatic vegetation is less in 2016–2017, all around 10 km2. The second stage is after the removal of the fence, the distribution area of aquatic vegetation in 2018 is on an upward trend, and in 2019–2022 it is growing rapidly. (3) Spatially, the aquatic vegetation was mainly distributed at the former fence, specifically in the northeastern and southwestern waters of the Futou Lake and it spread to the core area of the lake, probably due to the elevation of the siltation of the lake bottom. (4) Potamogeton crispus and Trapa are the dominant species, the peak of the distribution range in Futou Lake occurs in 2021 with an area of about 50.89 km2, which needs to be controlled moderately. (5) The area covered by Potamogeton crispus in the Futou Lake has increased significantly, probably due to the siltation and accumulation of nutrients in the Futou Lake caused by the history of purse seine farming.

Based on the artificial viscosity approach, a characteristic stabilized finite element method is proposed for approximating solutions to the incompressible Navier–Stokes equations in this paper. The natural combination of characteristic method and subgrid artificial viscosity stabilized finite element method retains the best features of both methods. The stability analysis and error estimates are deduced rigorously. Finally, some numerical experiments are given to demonstrate that this method is highly efficient for the nonstationary Navier–Stokes problems.

In this paper we reported that the pulsed dielectric barrier discharge was used to deposit functional films from allylamine vapors. The influence of processing parameters on the film characteristics was investigated in detail. The film property was measured by water contact angle, and the chemical compounds were analyzed by Fourier-transform infrared spectroscopy and ultraviolet-visible measurement. Atomic force microscopy was employed to scan the film morphology, and the density of amino group on surface was estimated using fluorescence measurements technology. The results of this work should be of specific value with respect to tissue culture studies, in which surface modifications involving the introduction of functional groups demonstrated a high efficacy in promoting cell growth.

This experiment is based on the theory of process-oriented approach from social cognitive psychology perspective and the theories of genre analysis from the angle of functional linguistics and social-linguistics. It is a practical research which aims for the teaching reform of English writing at the college level in China. It has been implemented in the last four years, which is a continuation of the teaching experiment adopting the “genre analysis approach” from 2005 to 2009. The purpose of the reform is to further promote the exploration into and research on teaching English writing in regular institutions of higher learning. The subjects involved in this round of experiment are 400 sophomores majoring in English from a provincial regular institution of higher learning. The paper reports the visible progress made in students' writing resulting from the reform in the teaching approach and the improvement in the teaching environment and teaching means.

Hexagon-arranged pattern is formed in a dielectric barrier discharge employing a radio frequency power source, where argon mixed with a small concentration of nitrogen was used as discharge gas. The pattern formations were observed through a water electrode. In this paper, the influence of applied voltage and the concentration of nitrogen in the mixture gases on the pattern formation were emphasized.