Study of Charged Property on the Interface of Porous Membrane of Anodized Aluminum

采用电渗方法研究了经硫酸溶液氧化并利用逆向电解方法剥离后的铝阳极氧化多孔膜层的ζ电位与溶液ｐＨ的关系．结果表明：该多孔膜层在１．０×１０－２ｍｏｌ／ＬＫＣｌ溶液中的ｐＨ等电点（ｐＨＩＥＰ）＝９．２０，２．００＜ｐＨ＜９．２０，ζ＞０，多孔膜荷正电；９．２０＜ｐＨ＜１１．００，ζ＜０，多孔膜荷负电．Using electrodialytic method, the relation between the pH value of tested solution and the ζ potential of porous anodized aluminum membrane, which was separated by reverse electrolysis from aluminum substrate, has been investigated. The following results can be obtained in 1.0×10-2 mol/L KCl solution: The pHIEP(isoelectric potential) of the porous membrane is equal to 9.20; In the range of 2.00作者联系地址：湖南大学化学化工学院Author's Address: Coll. of Chem. and Chem. Eng.,Hunan Univ., Changsha, 41008

Investigation of Sodium Hypophosphite Anodic Oxidizing Behavior in the Process of Acid Electroless Nickel Deposition

采用线性电位扫描和交流阻抗法研究了酸性化学镀镍过程中还原剂次亚磷酸钠的阳极氧化行为．结果表明，次亚磷酸钠的氧化是一个复杂的电化学过程，其阳极氧化行为受本身浓度、溶液温度、阳极扫描速度以及Ｎｉ２ ＋ 的影响，在其氧化反应之前可能存在异相界面转化步骤，该步骤成为整个氧化过程的控制步骤The anodic oxidizing behavior of sodium hypophosphite in the process of electroless nickle deposition(pH=5.5) was investigated with the linear potential sweep method and alternating current impedance.The results indicated that,the oxidation of NaH 2PO 2 was a complicated electrochemical process and affected by the concentration of NaH 2PO 2, the temperature of the bath,the sweep rate and the existence of nickel ion. The NaH 2PO 2 electrooxidation reaction was very likely preceded by heterogeneous interface transformation process,which might be the control step of the whole anodic process.作者联系地址：湖南大学化学化工学院!长沙410082湖南化工研究院长沙410007,湖南大学化学化工学院!长沙410082,湖南大学化学化工学院!长沙410082Author's Address: Coll. of Chem.and Chem.Eng.,Hunan Univ.,Changsha 41008

Influence of Electrolytes to the Interfacial Electroc Characteristics of the Porous Membrane of Anodized Aluminum

采用电渗法研究了电解质溶液组分对铝阳极氧化多孔膜层界面电性能的影响．结果表明，多孔膜分别经含Ｆ－、ＰＯ３－４、ＳｉＯ２－３或单宁酸溶液浸泡处理后，膜在０．０１ｍｏｌ／ＬＫＣｌ溶液中的等电点由原来的ｐＨＩＥＰ＝９．２０分别移至ｐＨＩＥＰ＝３．４０，４．３０，３．３０和４．５０；ｐＨ＜ｐＨＩＥＰ时，多孔膜荷正电，ｐＨ＞ｐＨＩＥＰ时多孔膜荷负电，膜的ζ电位—ｐＨ曲线也发生了变化．经酸性品红和碱性品红溶液浸泡后的多孔膜，在２．０＜ｐＨ＜１１．０范围无等电点，膜的ζ电位始终大于零（碱性品红浸泡），ζ电位始终小于零（酸性品红浸泡）．The influence of electrolytic composition on the interfacial electric Characteristic of the porous membrane membrance of anodized aluminum was investigated with a electrodialytic method. Results indicated that, when the porous membrane was pretreated with F -, PO 3- 4,SiO 2- 3 and tannic acid, the isoelectric point in 0.01 mol/L KCI, were shifted from normal 9.20 to 3.40, 4.30, 3.30 and 4.50, respectively, and responsive characteristics of ζ potential to pH was changed. Furthermore, after pretreatment of porous membrance with fuchsine basic and fuchsine acid solution,there was no isoelectric point at 2.0作者联系地址：湖南大学化学化工学院Author's Address: Coll. of Chem.and Chem.Eng.,Hunan Univ,Changsha 41008

An ESR Study of Free Radicals in Electroreduction Process of Allyl Alcohol

烯丙醇电还原自由基中间产物的ＥＳＲ研究张敬东，旷亚非，黄树坤，谢乃贤（湖南大学化学化工系，长沙４１００８２）汪风珍，陈德文（中南工业大学测试中心，长沙４１００８３）（中国科学院化学研究所，北京１０００８０）Ｈｏｒａｎｙｉ［１］、陈剑［２］等人对酸性水...Electrochemical-ESR technique with spin trap phenyl-t-butyl nitrone(PBN)was used to study the intermediates of electroreduction of allyl alcohol at platinized platinum electrode in acidic alcohol-aqua solution. Hydrogen and allyl group and(or)propyl group radicals were identified by a hyperfine spectrum of the radical adducts,and that provided a direct evidence for the presence of these radicals in the electroreduction of allyl alcohol.作者联系地址：湖南大学化学化工系，中南工业大学测试中心，中国科学院化学研究所，长沙水利电力学院化学系Author's Address: Dept.of Chem.and Chem. Eng.,Hunan University,Changsha 410082Wang FengzhenCentre Laboratory,Centre South University of Technology,Changsha 410083Chen DewenInst.of Chem.,Academia Sinica,Beijinq,10008