• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Control of Interfacial Cl-2 and N2O5 Reactivity by a Zwitterionic Phospholipid in Comparison with Ionic and Uncharged Surfactants
【24h】

Control of Interfacial Cl-2 and N2O5 Reactivity by a Zwitterionic Phospholipid in Comparison with Ionic and Uncharged Surfactants

机译：与离子和非充电表面活性剂相比，通过两性离子磷脂控制界面C1-2和N2O5反应性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Gas liquid scattering experiments reveal that charge-separated but neutral (zwitterionic) surfactants catalyze the oxidation of dissolved Br- to Br-2 by gaseous Cl-2 at the surface of a 0.3 M NaBr/glycerol solution. Solutions of NaBr dissolved in glycerol with no surfactant were compared with solutions coated with zwitterionic, cationic, and anionic surfactants at dilute surface concentrations of 1.1 to 1.5 X 10(14) cm(-2) (less than 65% of maximum chain packing). The zwitterionic phospholipid enhances Cl-2 conversion of Br- to Br-2 by a factor of 1.61 +/- 0.15, in comparison with a 14-fold enhancement by a cationic surfactant (tetrahexylammonium) and a five-fold suppression by an anionic surfactant (dodecyl sulfate). Further studies indicate that even an uncharged surfactant, monododecanoylglycerol, enhances Cl-2 - Br-2 production. Similar behavior is observed for the oxidation of Br- to Br-2 by N2O5; it is just slightly suppressed by the phospholipid and strongly enhanced by the cationic surfactant. Collectively, these results suggest that attractions and repulsions between the negative Br- ions and the positive and negative charges of the surfactant headgroups draw Br- ions to the surface or repel them away. At low coverages, ion-induced dipole and dispersion interactions between the CH2 groups and Br- or Cl-2 may also enhance reactivity. These results demonstrate that the hydrocarbon chains of loosely packed surfactants do not necessarily block gas liquid reactions but that positively charged, and even uncharged, groups can instead facilitate reactions by bringing gas-phase and solution-phase reagents together in the interfacial region.
机译：气体散射实验表明，电荷分离但中性（两性离子）表面活性剂在0.3M Nabr /甘油溶液的表面上通过气态Cl-2催化溶解的Br-2的氧化。将NaBr的NaBr溶解在没有表面活性剂的甘油中，与涂覆有两性离子，阳离子和阴离子表面活性剂的溶液，以1.1-1.5×10（14）厘米（-2）（少于最大链填料的65％） 。双层磷脂通过阳离子表面活性剂（四氧基铵）的14倍的增强，增强了Br-2转化为1.61 +/- 0.15的倍数1.61 +/- 0.15。通过阴离子表面活性剂的抑制率为5倍抑制（十二烷基硫酸盐）。进一步的研究表明，即使是一种不带电的表面活性剂，甲二烯癸酰甘油，增强Cl-2 - ＆ BR-2生产。通过N2O5氧化BR-2的氧化类似的行为;磷脂略微抑制，阳离子表面活性剂强烈地增强。总的来说，这些结果表明，表面活性剂头组的阴性条纹与正极和负电荷之间的吸引力和排斥将BRIONS绘制到表面或击退它们。在低覆盖范围内，CH2基团和BR-2之间的离子诱导的偶极和分散相互作用也可以增强反应性。这些结果表明，松散填充的表面活性剂的烃链不一定阻断液体反应，而是带正电荷，甚至没有充电的基团可以通过将气相和溶液相试剂在界面区域中聚集在一起来促进反应。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号