对混凝-超滤工艺在线化学强化反冲洗(chemically enhanced blackwash,CEB)过程中产生的副产物进行了分析,建立和优化了高效液相色谱质谱法(HPLC-MS/MS)测定反冲洗副产物中卤乙酸的分析方法.方法采用Zobax Plus Eclipse C8色谱柱,流速0.3...对混凝-超滤工艺在线化学强化反冲洗(chemically enhanced blackwash,CEB)过程中产生的副产物进行了分析,建立和优化了高效液相色谱质谱法(HPLC-MS/MS)测定反冲洗副产物中卤乙酸的分析方法.方法采用Zobax Plus Eclipse C8色谱柱,流速0.3 m L/min,进样量10μL,R2均在99.9%以上,最小检出限为0.08μg/L.在此基础上监测了CEB后24 h卤乙酸浓度的变化规律.结果表明:CEB过程中有清洗副产物卤乙酸的生成,且随着膜过滤出水时间的延长,大部分卤乙酸浓度逐渐降低.其中三氯乙酸生成量最高;其次为三溴乙酸.另外二溴乙酸浓度随时间无明显变化;二氯乙酸、三溴乙酸、一氯一溴乙酸和一氯二溴乙酸分别会在16、17、18、19 h达到浓度动态平衡.展开更多
The mesoscopic phase of block copolymers PAn-PEG-PAn in aqueous solution was investigated by dissipative particle dynamics(DPD)simulation.The effects of the molar fraction of PAn segment in the copolymers and its conc...The mesoscopic phase of block copolymers PAn-PEG-PAn in aqueous solution was investigated by dissipative particle dynamics(DPD)simulation.The effects of the molar fraction of PAn segment in the copolymers and its concentration on the copolymers’ self-assembling were discussed.The distribution of PEG and PAn segments on the surface of the spherical micelle of the copolymer was interesting but was difficult to observe by experiments.The authors focused on investigating the characteristics of the spherical micelle of the copolymers in a low concentration.There existed two novel core-shell spherical micelles separately with increasing molar fraction of the PAn segment.One was that the PAn segment made up the shell and the PEG segments the core;the other was that the PEG segments made up the shell and the PAn segments the core.A greater part of water was aggregated to form cylindrical and spherical micelles,while the remaining was distributed in the block copolymers symmetrically when the mass fraction of the copolymers was more than 66.7%.DPD simulation could be considered as an assistant for the experimental research and could provide useful information which is difficult to obtain by experiments.展开更多
文摘对混凝-超滤工艺在线化学强化反冲洗(chemically enhanced blackwash,CEB)过程中产生的副产物进行了分析,建立和优化了高效液相色谱质谱法(HPLC-MS/MS)测定反冲洗副产物中卤乙酸的分析方法.方法采用Zobax Plus Eclipse C8色谱柱,流速0.3 m L/min,进样量10μL,R2均在99.9%以上,最小检出限为0.08μg/L.在此基础上监测了CEB后24 h卤乙酸浓度的变化规律.结果表明:CEB过程中有清洗副产物卤乙酸的生成,且随着膜过滤出水时间的延长,大部分卤乙酸浓度逐渐降低.其中三氯乙酸生成量最高;其次为三溴乙酸.另外二溴乙酸浓度随时间无明显变化;二氯乙酸、三溴乙酸、一氯一溴乙酸和一氯二溴乙酸分别会在16、17、18、19 h达到浓度动态平衡.
文摘The mesoscopic phase of block copolymers PAn-PEG-PAn in aqueous solution was investigated by dissipative particle dynamics(DPD)simulation.The effects of the molar fraction of PAn segment in the copolymers and its concentration on the copolymers’ self-assembling were discussed.The distribution of PEG and PAn segments on the surface of the spherical micelle of the copolymer was interesting but was difficult to observe by experiments.The authors focused on investigating the characteristics of the spherical micelle of the copolymers in a low concentration.There existed two novel core-shell spherical micelles separately with increasing molar fraction of the PAn segment.One was that the PAn segment made up the shell and the PEG segments the core;the other was that the PEG segments made up the shell and the PAn segments the core.A greater part of water was aggregated to form cylindrical and spherical micelles,while the remaining was distributed in the block copolymers symmetrically when the mass fraction of the copolymers was more than 66.7%.DPD simulation could be considered as an assistant for the experimental research and could provide useful information which is difficult to obtain by experiments.
