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The widespread environmental contamination resulting from the misuse of tetracycline antibiotics (TCs) has garnered significant attention and study by scholars. Photocatalytic technology is one of the environmentally friendly advanced oxidation processes (AOPs) that can effectively solve the problem of residue of TCs in the water environment. This study involved the synthesis of the heterogeneous magnetic photocatalytic material of CoFe2O4/NaBiO3 via the solvothermal method, and it was characterized using different characterization techniques. Then, the photocatalytic system under visible light (Vis) was coupled with peroxymonosulfate (PMS) to explore the performance and mechanism of degradation of tetracycline hydrochloride (TCH) in the wastewater. The characterization results revealed that CoFe2O4/NaBiO3 effectively alleviated the agglomeration phenomenon of CoFe2O4 particles, increased the specific surface area, effectively narrowed the band gap, expanded the visible light absorption spectrum, and inhibited recombination of photogenerated electron–hole pairs. In the Vis+CoFe2O4/NaBiO3+PMS system, CoFe2O4/NaBiO3 effectively activated PMS to produce hydroxyl radicals (·OH) and sulfate radicals (SO4−). Under the conditions of a TCH concentration of 10 mg/L−1, a catalyst concentration of 1 g/L−1 and a PMS concentration of 100 mg/L−1, the degradation efficiency of TCH reached 94% after 100 min illumination. The degradation of TCH was enhanced with the increase in the CoFe2O4/NaBiO3 and PMS dosage. The solution pH and organic matter had a significant impact on TCH degradation. Notably, the TCH degradation efficiency decreased inversely with increasing values of these parameters. The quenching experiments indicated that the free radicals contributing to the Vis+CoFe2O4/NaBiO3+PMS system were ·OH followed by SO4−, hole (h+), and the superoxide radical (O2−). The main mechanism of PMS was based on the cycle of Co3+ and Co2+, as well as Fe3+ and Fe2+. The cyclic tests and characterization by XRD and FT-IR revealed that CoFe2O4/NaBiO3 had good degradation stability. The experimental findings can serve as a reference for the complete removal of antibiotics from wastewater. [ABSTRACT FROM AUTHOR]

【Background and objective】 Evaporation and its associated salt accumulation on the soil surface is an abiotic stress facing agricultural production in arid and semi-arid regions, and how to alleviate its detrimental impact is a topic that continues to attract interest from both researchers and practitioners. Cutting the capillary connection in soil is one technology and the purpose of this paper is to investigate the feasibility of burying a straw interlayer in soil to slow down evaporation and salt migration from groundwater. 【Method】 The experiments were conducted in columns filled with saline soil taken from a cotton field that has been watered by film-mulched drip irrigation in southern Xinjiang. The groundwater table was controlled at the depths of 1.0 m, 1.5 m and 2.0 m respectively, with a cotton straw interlayer buried at a depth between 15 cm and 60 cm from the soil surface. In each treatment, we measured water evaporation and salt accumulation on the soil surface. 【Result】 ①The cumulative evaporation and daily evaporation rate both decreased as the groundwater table depth increased, with the average daily evaporation rate being 1.73 mm/d, 1.12 mm/d and 0.49 mm/d, respectively, when the groundwater table was 1.0 m, 1.5 m and 2.0 m deep. The cotton straw layer reduced water evaporation with the reduction depending on its burying depth. The reduction was the highest when its buying depth was 15 cm, and the least when the burying depth was 30 cm. ②Salt accumulation in 0~30 cm soil layer decreased as the groundwater depth increased, with daily accumulation rate being 0.031 g/kg/d, 0.012 g/kg/d and 0.004 g/kg/d, respectively, when the groundwater table depth was 1.0 m, 1.5 m and 2.0 m without the straw layer. The efficacy of the straw layer in reducing evaporation was more noticeable in the early stage of the experiment, and was most effective when being buried at the depth of 15cm. When groundwater table was 1 m, 1.5 m and 2.0 m deep, burying the straw 15 cm deep reduced daily slat accumulation in the 0~30 cm of soil by 71.25%, 87.15% and 90.58%; 41.91%, 37.85% and 34.90%; and 20.45%, 26.63% and 33.33%, respectively, compared with that buying it at 30 cm, 45 cm and 60 cm deep. ③The accumulated salt in 0~30 cm soil increased linearly with soil water evaporation. 【Conclusion】 The accumulated salt on the soil surface and daily evaporation from groundwater both decreased as groundwater depth increased. Regardless of its burying depth, the cotton straw layer reduced groundwater evaporation and salt accumulation in 0~30 cm soil, but it was most effective when being buried at the depth of 15 cm. We also found that the accumulated salt in the 0~30 cm soil increased linearly with water evaporation.

The biodegradable materials cannot meet the requirements as the agricultural film due to the poor UV resistance and antidripping performance. The work herein thus presented the development of the green‐based anti‐ultraviolet and antidripping multifunctional composite films using poly(butyleneadipate‐co‐terephthalate), microfibrillated cellulose (MFC), and soybean protein isolate (SPI) as the raw materials in the presence of other agents. The resulting composite films were systematically characterized using scanning electron microscope, thermogravimetry analysis (TG), UV, and rheometer measurements. The morphology changed obviously after introducing the MFC and SPI into the substrate film. In addition, the results indicated that the addition of MFC and SPI had a positive effect on the thermal stability and heat preservation of the film, respectively. The contact angle results indicated that SPI was an ideal antidripping agent and the MFC could be used as the release agent. The time of the first water drop of the film containing 2.5 g MFC and 2.0 g SPI was 6 min and 46 s, and the time of each 10 drops was less than 60 s, showing the advantages of using MFC as the release agent and SPI as the antidripping agent. The resulting multifunctional biodegradable films can be widely used in the agricultural and packaging fields. [ABSTRACT FROM AUTHOR]

The potential application of zinc air batteries to tackle the energy shortage and environmental crisis has proposed new requirements of bifunctional catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Utilizing the special spatial structure of zeolitic imidazolate framework-67 (ZIF-67) as an ideal research platform, the effect of a trace amount of Fe on the composition and structure of as-obtained Fe-CoNC catalysts was investigated. It was revealed that, due to the increased exposed pore structure and metal species located at the near surface, the active sites for the ORR/OER on Fe-CoNC are highly exposed, greatly boosting the activity to the reduction and evolution of oxygen in alkaline media. ZABs with Fe-CoNC have the highest maximum power density of 200 mW cm−2 when operated at current densities as high as 328 mA cm−2, better than not only Fe-free CoNC, but also precious metal-based references with the same catalyst loading. [ABSTRACT FROM AUTHOR]