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The performance of traditional and magnetized activated sludge treatment systems was compared in a sequencing batch reactor. Four influencing factors, namely, magnetic powder dosage, temperature, aeration time, and magnetic field size, which affected the efficiency of sludge treatment were investigated with the evolution of the principal sewage indexes: chemical oxygen demand, ammonia nitrogen, total nitrogen, and total phosphorus. Results revealed that the efficiency of sewage treatment with magnetized activated sludge was better than that of traditional activated sludge. Its elimination rates of COD, ammonia nitrogen, TN, and TP were approximately 96.4%, 98.9%, 86.4%, and 94.2%, respectively, compared with the activated sludge that was not exposed to a magnetic field (90.7%, 78.4%, 53.5%, and 87%, respectively). The magnetic powder dosage of 0.5 g/L was optimal for pollutant removal. The temperature of 25 °C-30 °C, aeration time of 4 h, and applied magnetic field of 200 Gs achieved the best effect in the comprehensive consideration of economic aspects and processing indicators. [ABSTRACT FROM AUTHOR]

With the increasing awareness of environmental protection, environmental protection factors are gradually reflected in landscape art design. This paper analyses the concept of low-carbon environmental protection, expounds the characteristics of landscape design, and then analyses the embodiment of environmental protection factors from three aspects: landscape plant design, landscape material design and landscape management. [ABSTRACT FROM AUTHOR]

The Adsorption of nitrobenzene by using NaOH as an activator to modified sugarcane bagasse was investigated, and various factors, such as adsorbent dosage, adsorption time, and initial concentration of nitrobenzene, affecting the amount of adsorption were explored. Adsorption experimental results revealed that the adsorption equilibrium time was 20, 15, and 10 min at 25 °C, 35 °C, and 45 °C, respectively. The adsorption behavior most appropriately fit the pseudo-second-order kinetic equation with a regression coefficient of R²>>0.9998, and the calculated apparent activation energy was positive (47.956 kJ/mol). The Langmuir model was in accordance with the experimental data (R²>0.9919). According to Langmuir isotherm linear analysis, the maximum adsorption capacities were 76.98, 77.52, and 78.25 mg/g at 25 °C, 35 °C and 45 °C, respectively. Sorption mainly relied on π-π dispersion force adsorption. As a result, the modified sugarcane bagasse sorbent could be used as a possible alternative to remove nitrobenzene from aqueous solutions. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To establish a comprehensive analytical method based on SPE-UPLC-MS for the simultaneous determination of bisphenol A (BPA), nonylphenol (NP), and octylphenol (OP) in urine samples. Methods: Sixty urine samples collected from healthy subjects were analyzed for BPA, NP, and OP concentrations. The samples were de-conjugated by adding β-glucuronidase and sulfatase. After the enzymatic treatment, the samples were subjected to the OASIS HLB column solid phase extraction cartridges so as to be cleaned and concentrated. The UPLC separation was performed on a Acquity UPLCTM BEH C18 column (2.1×100 mm, 1.7 μm) with a gradient elution system of methanol-water as the mobile phase. Triple-quadrupole mass spectrometry analyzer was used for the qualitative and quantitative analysis of UPLC-MS/MS system. Results: The limit of detection of BPA, NP, and OP was 0.10, 0.10, and 0.15 ng/mL, respectively. The recoveries of BPA, NP and OP were 80.1%-108%, 81.3%-109%, and 81.5%-98.7%, respectively. Among the 60 urine samples, BPA was detected in 8 samples at the level of 0.297-32.7ng/mL, NP was detected in 29 samples at the level of 1.69-27.8 ng/mL, and OP was detected in 17 samples at the level of 0.407-11.1 ng/mL. Conclusion: The method is simple with high sensitivity and selectivity, and is suitable for the determination of BPA, NP, and OP in urine. As shown by our analysis, BPA, NP, and OP appear to be prevalent in human urine. This is particularly true for NP. The results from our study is therefore valuable for future studies to assess the exposure to BPA, NP, and OP in the general population. [Copyright &y& Elsevier]