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[Display omitted] Bimetal oxide is a popular defluorinating material. Hexadecyl trimethyl ammonium bromide (CTAB) as a surfactant successfully synthesizes a novel lanthanum-zirconium phosphate to remove fluorine from groundwater. Lanthanum-zirconium phosphate at a Zr/La molar ratio of 2 exhibited a specific surface area of 455.14 m2/g with a wide pore size, which was achieved by incorporating lanthanum into materials and removing CTAB through calcination. The maximum fluoride adsorption capacity is 109.17 mg/g, which is tenfold that of mesostructured zirconium phosphate. Specifically, analysis revealed that mZrP and LamZrP2-1 were amorphous, which is consistent with HAADF-STEM. The fluoride adsorption fitted well with the pseudo-second-order equation model and Langmuir isotherm mode. LamZrP2-1 had potent anti-interference ability without PO43-. Moreover, LamZrP2-1 was reusable for at least six cycles of adsorption–desorption with little influence. The adsorption mechanism of fluoride was discussed by X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance spectroscopy (NMR) analysis, and Fourier transform infrared (FTIR) spectroscopy. Fluoride was captured by LamZrP2-1 via charge attraction, ligand exchange of different bond strengths, and ion exchange. Lanthanum-zirconium phosphate is important not only in the research and development of bimetal oxides but also in the treatment of groundwater for fluoride removal. [ABSTRACT FROM AUTHOR]

Given the ubiquitous detection of antibiotics and antibiotic resistance genes (ARGs) in waterbodies worldwide and increasing public attention to water resource safety, this study investigated the presence of antibiotics and ARGs in the water sources of the Wuhan stretch of the Yangtze River (YR) as well as potential ecological risks. In this study, 15 antibiotics and 10 ARGs in a source of drinking water were analyzed using solid-phase extraction-ultra performance liquid chromatography-mass spectrometry technology (SPE–UPLC–MS/MS) and real-time fluorescence quantitative polymerase chain reaction (qPCR). Fourteen antibiotics were detected in the samples from 18 water sources, with the highest concentration detected for tetracycline, reaching up to 1708.33 ng/L. The detection rates of norfloxacin, enrofloxacin, ofloxacin, tetracycline, and roxithromycin were 100%. The concentrations of antibiotics were highest in She Shui, followed by the Wuhan stretch of the lower reaches of the YR, whereas the lowest concentrations were found in the Wuhan stretch of the upper reaches of the YR which were approximately equal to those in the Han River (HR). Ofloxacin and roxithromycin presented a substantial threat to aquatic organisms with high sensitivity at the majority of the sampling sites. The overall abundance of ARGs was notably greater in the lower reaches of the YR compared with the upper reaches and the HR. The highest absolute abundance was observed for sulfa ARGs. Integron intl1 strongly correlated with sul1, sul2, ermB, and qnrS, and antibiotics, strongly correlated with multiple ARGs, suggesting that antibiotics and ARGs are present in water sources in Wuhan and may present a plausible hazard to both human and ecological well-being. Hence, regulating the spread and dissemination of antibiotics and ARGs in the environment is imperative. The findings of this research offer significant insights into the stewardship and safeguarding of aquatic reserves in the Wuhan stretch of the YR. • Detection rates of antibiotic resistance genes (ARGs) were 100%. • Total concentration of antibiotics reached 1708.33 ng/L. • Antibiotics and ARGs are present in water sources in Wuhan. • Antibiotics and ARGs present a plausible hazard to human and environmental health. • Spread of antibiotics and ARGs in the environment must be controlled. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract In this study, we prepared a hydrothermal carbon-based supramolecular organic framework (HTC-MA-TMA) by grafting melamine and trimesic acid on hydrothermal carbon (HTC) for efficient removal of U (VI) from aqueous solutions. The nano-sized supramolecular organic framework (SOF) particles consisted of N-donor-containing melamine and O-donor-containing trimesic acid self-assembled through hydrogen bonds. Their large number of specific active sites acted as the immobilization center for capturing U (VI). Chemical modification facilitated the dispersion of the SOF particles on HTC, which was synthesized using a novel covalent/non-covalent bond strategy. The HTC-MA-TMA adsorbent exhibited exceptional U (VI) adsorption capacity (271.83 mg/g) because of the coordination interaction between UO 2 2+ and its ligands (amino, carboxyl and amide groups). The adsorption equilibrium was achieved within 30 min and followed a pseudo-second-order equation, suggesting the occurrence of a chemical adsorption process. Furthermore, the U (VI) ions adsorbed onto the HTC-MA-TMA adsorbent could be easily desorbed using 0.1 M HNO 3 solution. This regeneration caused no significant decrease in the sorption capacity of the adsorbent. These results suggest that advanced HTC-MA-TMA adsorbent can be applied in the nuclear-fuel industry for extracting U (VI) from radioactive wastewater. [ABSTRACT FROM AUTHOR]

Neonicotinoids, as the most widely used pesticides in the world, help improve the production of crops. Meanwhile, it also brings potential threats to surrounding environments and other organisms because of its wide use and even abuse. In this study, Scenedesmus sp. TXH isolated from a wastewater treatment plant was used to remove the neonicotinoid pesticide thiamethoxam (THIA). The removal efficiency, degradation pathway, metabolite fate of THIA and physicochemical effects on microalgae cells were studied. Meanwhile, the feasibility of using microalgal technology to remove THIA from municipal wastewater was also explored. The results showed that 5–40 mg/L of THIA slightly promoted the growth of microalgae, while 60 mg/L THIA severely inhibited microalgal growth. It was observed that malondialdehyde content and superoxide dismutase activity in 60 mg/L THIA group increased significantly (p < 0.05) in the early stage of the experiment, indicating that THIA caused oxidative damage to microalgae. Scenedesmus sp. TXH showed high-efficient degradation ability and high resistance to THIA, with 100% removal of THIA at 5, 20 and 40 mg/L groups and 97.5% removal of THIA at 60 mg/L group on day 12. THIA was mainly removed by biodegradation, accounting for 78.18%, 93.50%, 96.81% and 91.35% under 5, 20, 40 and 60 mg/L on day 12, respectively. Six degradation products were identified, and four potential degradation pathways were proposed. In practical wastewater, the removal efficiency of total dissolved nitrogen, total dissolved phosphorus, ammonia nitrogen and THIA reached 85.68%, 90.00%, 98.43% and 100%, respectively, indicating that Scenedesmus sp. TXH was well adapted to the wastewater and effectively removed THIA and conventional pollutants. [Display omitted] • MDA and SOD of Scenedesmus sp. TXH were significantly increased in 60 mg/L THIA. • Scenedesmus sp. TXH was tolerant to THIA, and could withstand its high doses. • Biodegradation played a key role in THIA removal. • Six degradation products and four potential degradation pathways were proposed. • Scenedesmus sp. TXH showed excellent THIA removal performance in wastewater. [ABSTRACT FROM AUTHOR]

Complete autotrophic nitrogen removal over nitrite (CANON) is used in wastewater treatment. However, the performance of the CANON system significantly decreases at low temperatures; thus, a new strategy to improve the resistance of the CANON system is required. To investigate the impact of sludge ratio control (high-granule, equivalent, and high-floc systems) on the resistance of CANON to low temperatures, and their recovery after restoring to normal temperature, the nitrogen removal performance of hybrid systems with different ratios was evaluated. The equivalent system had the lowest nitrite accumulation rate and highest nitrogen removal rate. Anaerobic ammonia oxidation was the rate-limiting step of each system, and hzs was the rate-limiting gene. The higher anaerobic ammonium oxidizing bacteria (AAOB) abundance and hzs expression levels resulted in an equivalent system with better resistance and recovery to short-term low temperatures at the gene level. [Display omitted] • Nitrogen removal performance of CANON system with different sludge ratios studied. • Resistance to low temperature and recovery of CANON system was evaluated. • Systems with different sludge ratios have varied resistance to low temperatures. • Biofortification has a positive effect on the gene transcription process. [ABSTRACT FROM AUTHOR]