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Corrosion behavior of AZ31 magnesium alloy in NH 4 +-bearing chloride solution with controlled pH was investigated by weight loss experiment, hydrogen collection, and electrochemical test combined with surface morphology and topography observation. The results show that NH 4 + and pH of the solution can affect the corrosion of AZ31 magnesium alloy. The existence of NH 4 + affects the formation and dissolution of corrosion products, which makes the protective effect of the corrosion product layer weaker. The change of pH value not only affects the corrosion mechanism of AZ31, but also alters the concentration of NH 4 + ions in the solution, which further influences the corrosion product layer of AZ31, and finally makes the corrosion of AZ31 change significantly. [ABSTRACT FROM AUTHOR]

Effective and reliable uptake rates are crucial for applying passive samplers in monitoring gaseous volatile organic compounds (VOCs). However, there is currently a lack of data regarding the 24-h passive uptake rates of VOCs for workplace and environmental monitoring. This study aims to address this gap by utilizing a Tenax TA-based sampling tube to investigate the 24-h uptake rates of 25 kinds of VOCs in enclosed ship cabin environments. The results reveal that the uptake rate of VOCs ranges from 0.32 to 0.44 mL/min. A relationship between diffusive uptake rates and the boiling point of the compounds is proposed. The variation in uptake rate under different sampling durations was examined. The difference in uptake rate between 24 h and 8 h was smaller than that between 24 h and 6 days, with an average difference of 20%. In addition, the indoor uptake rate obtained in this study was compared with the outdoor uptake rates in the literature, and results showed that the outdoor uptake rate was generally higher than the indoor uptake rate, but the difference decreased when the sampling duration was longer. Field measurement was conducted by utilizing the measured uptake rates to characterize VOC pollution in both living and engine cabins in actual ships. This study contributes to facilitating the evaluation of environmental daily average concentrations in enclosed ship cabins, which will be helpful for assessing the effectiveness of air pollution control systems or epidemiological studies in ships. • 24h uptake rates of 25 kinds of VOCs under vessel environment were estimated. • A relationship between diffusive uptake rates and boiling point is proposed. • The difference in uptake rate under different sampling duration can reach 70%. • A field measurement campaign in a real vessel was conducted for VOC characterization. [ABSTRACT FROM AUTHOR]