饮用水中三氯甲烷与其他氯消毒副产物在活性炭上的吸附竞争研究

通过等温吸附实验，探究了三氯甲烷（CHCl₃）与二氯一溴甲烷（CHBrCl₂）、二氯乙酸（Cl₂CHCOOH）在活性炭上的竞争吸附关系，同时探究了在低浓度条件下CHBrCl₂和Cl₂CHCOOH浓度变化对活性炭吸附CHCl₃的影响。实验结果表明，活性炭吸附CHCl₃和CHBrCl₂符合Freundlich模型，对Cl₂CHCOOH的吸附符合Langmuir模型；活性炭对3种消毒副产物均为优先吸附，吸附能力由大到小依次为CHBrCl₂、CHCl₃、Cl₂CHCOOH；低浓度条件下，活性炭对消毒副产物的吸附效果随体系中物质种类的增加而降低；低浓度条件下，Cl₂CHCOOH的浓度变化对CHCl₃的吸附效果影响不大，但吸附效果随水体中CHBrCl₂浓度的升高而降低。

Enantioseparation of Betti bases on chiral stationary phase by HPLC

In this paper, the separation of 1-(α-aminobenzyl)-2-naphthol, 1-(α-benzylaminobenzyl)-2-naphthol and 1-(α-piperidylbenzyl)-2-naphthol is studied on two chiral columns-Chiralcel OD-H and (R,R)-Whelk-O1 chiral columns. The influence of the structures on the chiral separation is investigated. The influence of the mobile phase composition including the concentration and type of the alcohol modifiers and the basic additive in hexane, the separation factor (α) and the resolution (Rs) are studied. Then the two different chiral recognition mechanisms are discussed and compared. 1-(α-aminobenzyl)-2-naphthol and 1-(α-benzylaminobenzyl)-2-naphthol and 1-(α-piperidylbenzyl)-2-naphthol can be baseline separated on chiralcel OD-H using hexane-iso-propanol (95:5, v/v) as eluent under a flow rate of 0.5 mL·min^－1 at 25 °C. On (R,R)-Whelk-O1, the attractive interactions between CSP and solute are the key factor for retention and chiral recognition, on chiralcel OD-H, the steric fit of solute into the chiral cavity maybe the predominant factor for the chiral recognition of 1-(α-benzylaminobenzyl)-2-naphthol and 1-(α-piperidylbenzyl)-2-naphthol.