通过调整酒石酸钾钠与氢氧化钠的用量组合,对晋安区某垃圾渗滤液处理厂出口尾水氨氮测定的前处理方式进行优化实验。结果表明:当水样中钙、镁离子总浓度≤540 mg/L时,采用“加入1.2 mL 500 g/L酒石酸钾钠混匀后,再添加1 mL 250 g/L氢氧...通过调整酒石酸钾钠与氢氧化钠的用量组合,对晋安区某垃圾渗滤液处理厂出口尾水氨氮测定的前处理方式进行优化实验。结果表明:当水样中钙、镁离子总浓度≤540 mg/L时,采用“加入1.2 mL 500 g/L酒石酸钾钠混匀后,再添加1 mL 250 g/L氢氧化钠”的前处理方案,可有效掩蔽钙、镁等金属离子对氨氮测定的干扰,保障测定准确性。展开更多
Poly(phenylene oxide)(PPO)exhibits excellent dielectric properties,making it an ideal substrate for high-frequency,high-speed copper-clad laminates.The phenolic hydroxyl group at the end of PPO plays a key role in its...Poly(phenylene oxide)(PPO)exhibits excellent dielectric properties,making it an ideal substrate for high-frequency,high-speed copper-clad laminates.The phenolic hydroxyl group at the end of PPO plays a key role in its reactivity.Accurately quantifying the phenolic hydroxyl content in PPO is essential but challenging.In this study,we proposed a method for measuring the phenolic hydroxyl content of PPO using differential UV absorption spectroscopy.In alkaline solutions,the phenolic hydroxyl in PPO completely ionizes to form phenoxide ions,leading to a significant increase in UV absorbance at approximately 250 and 300 nm.Notably,the differential UV absorbance at approximately 300 nm was directly proportional to the phenolic hydroxyl concentration.Using 2,6-dimethylphenol as a standard,a calibration curve was established to relate the phenolic hydroxyl concentration to differential UV absorbance at approximately 300 nm,providing a precise and straightforward method for phenolic hydroxyl quantification in PPO with distinct advantages over conventional techniques.展开更多
文摘通过调整酒石酸钾钠与氢氧化钠的用量组合,对晋安区某垃圾渗滤液处理厂出口尾水氨氮测定的前处理方式进行优化实验。结果表明:当水样中钙、镁离子总浓度≤540 mg/L时,采用“加入1.2 mL 500 g/L酒石酸钾钠混匀后,再添加1 mL 250 g/L氢氧化钠”的前处理方案,可有效掩蔽钙、镁等金属离子对氨氮测定的干扰,保障测定准确性。
基金the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(No.2023C01072)the Institute of Zhejiang University-Quzhou for their financial support。
文摘Poly(phenylene oxide)(PPO)exhibits excellent dielectric properties,making it an ideal substrate for high-frequency,high-speed copper-clad laminates.The phenolic hydroxyl group at the end of PPO plays a key role in its reactivity.Accurately quantifying the phenolic hydroxyl content in PPO is essential but challenging.In this study,we proposed a method for measuring the phenolic hydroxyl content of PPO using differential UV absorption spectroscopy.In alkaline solutions,the phenolic hydroxyl in PPO completely ionizes to form phenoxide ions,leading to a significant increase in UV absorbance at approximately 250 and 300 nm.Notably,the differential UV absorbance at approximately 300 nm was directly proportional to the phenolic hydroxyl concentration.Using 2,6-dimethylphenol as a standard,a calibration curve was established to relate the phenolic hydroxyl concentration to differential UV absorbance at approximately 300 nm,providing a precise and straightforward method for phenolic hydroxyl quantification in PPO with distinct advantages over conventional techniques.
