环形聚电解质电泳特征的分子动力学模拟
PDF下载 (367)段 超,童朝晖*.环形聚电解质电泳特征的分子动力学模拟[J].宁波大学学报(理工版),2017,30(1):99-103.DOI:
DUAN Chao,TONG Chao-hui*.Molecular dynamics simulation of electrophoretic characteristics for ring polyelectrolyte[J].Journal of Ningbo University(Natural Science & Engineering Edition),2017,30(1):99-103.DOI:
| Title: | Molecular dynamics simulation of electrophoretic characteristics for ring polyelectrolyte |
| 作者: | 段 超, 童朝晖* |
| Author(s): | DUAN Chao, TONG Chao-hui* |
| 关键词: | 聚电解质; 凝聚度; 电泳迁移率; 分子动力学 |
| Keywords: | polyelectrolyte; degree of condensation; electrophoretic mobility; molecular dynamics |
| 分类号: | O631.4 |
| 文献标识码: | A |
| 摘要: | 使用Langevin分子动力学模拟研究了环形聚电解质的电泳行为, 发现环形和线形链具有相似的临界电场强度. 当场强超出临界值, 平衡离子凝聚度急剧降低, 链构象明显溶胀. 相比线形分子, 环形链凝聚度降低的幅度较少, 源于环形链在电场中的构象拉伸度小于线形链. 在不考虑流体动力学相互作用的情况下, 2种分子链的电泳迁移率均满足“局部力平衡”关系. 在不同的溶液库仑强度下, 2种链的迁移率差异出现峰值, 电场增强导致峰值增大和峰位置右移. |
| Abstract: | The electrophoretic behaviors of ring polyelectrolyte (PE) are investigated using Langevin molecular dynamics simulation. It is found that ring PE has the similar critical electric field intensity as the linear one. When the field intensity exceeds the critical value, the degree of counter-ion condensation starts to decrease sharply and PE conformation swells significantly. However, the decreasing extent of ring PE is apparently less than that of the linear one. This outcome arises from the less extension degree of ring chain than the linear chain. Both electrophoretic mobilities of two chains subject to ‘local force equilibrium’ relationship without hydrodynamic interaction. For different Coulomb interaction intensity of solution, a peak value appears in the mobility difference of two chains. And stronger electric field induces larger peak value and right-shift of the peak. |
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| 备注/Memo: | 收稿日期: 2015?05?22. 宁波大学学报（理工版）网址: http://nbdxlg.paperopen.com/ 基金项目: 国家自然科学基金（21374052）. 第一作者: 段超（1989－）, 男, 江苏盐城人, 在读硕士研究生, 主要研究方向: 聚电解质溶液的分子模拟. E-mail: qcdandpolymer@163.com *通信作者: 童朝晖（1968－）, 男, 湖南常德人, 教授, 主要研究方向: 聚电解质理论. E-mail: tongchaohui@nbu.edu.cn 宁波大学学报（理工版）网址：http://journallg.nbu.edu.cn/ |
