物理化学学报 >> 2011, Vol. 27 >> Issue (11): 2499-2504.doi: 10.3866/PKU.WHXB20111102

热力学,动力学和结构化学 上一篇    下一篇

离子对液态水缔合构造影响的能量表征

和劲松1,2, 杨宏伟2, 甘晓玲1, 蔡然2, 朱松明1, 于勇1, 李建平1, 木泰华3, 祝万鹏2   

  1. 1. 浙江大学生物系统工程与食品科学学院, 杭州 310058;
    2. 清华大学环境科学与工程系, 北京 100084;
    3. 中国农业科学院农产品加工研究所, 北京 100094
  • 收稿日期:2011-06-01 修回日期:2011-07-15 发布日期:2011-10-27
  • 通讯作者: 朱松明, 木泰华 E-mail:zhusm@zju.edu.cn; mutaihua@126.com
  • 基金资助:

    浙江省重点科技创新团队(2009R50001)与浙江省教育厅(Y201018520)资助项目

Energy Characterization of Effect for Ions on the Structure of Water

HE Jin-Song1,2, YANG Hong-Wei2, GAN Xiao-Ling1, CAI Ran2, ZHU Song-Ming1, YU Yong1, LI Jian-Ping1, MU Tai-Hua3, ZHU Wan-Peng2   

  1. 1. College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, P. R. China;
    2. Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, P. R. China;
    3. Institute of Agro-Food Science & Technology, Chinese Academy of Agricultural Sciences, Beijing 100094, P. R. China
  • Received:2011-06-01 Revised:2011-07-15 Published:2011-10-27
  • Contact: ZHU Song-Ming, MU Tai-Hua E-mail:zhusm@zju.edu.cn; mutaihua@126.com
  • Supported by:

    The project was supported by the Key Scientific and Technological Innovation Team Project of Zhejiang Province, China (2009R50001) and Department of Education of Zhejiang Province, China (Y201018520).

摘要: 利用差示扫描量热法(DSC), 从能量变化的角度研究了在0-1.0 mol·L-1浓度范围内, KCl、MgCl2与CaCl2对液态水缔合构造的影响, 并与17O-NMR化学位移δ(17OH2)的分析结果进行比较. 随KCl、MgCl2与CaCl2浓度的升高, 液态水的δ(17OH2)呈线性增加, 而表观活化能(-E'/R)呈线性减小. 并且δ(17OH2)与-E'/R对盐类浓度的变化率的大小满足如下顺序: KCl < MgCl2 < CaCl2. 基于二态模型, 可以证明伴随盐类浓度的改变, 液态水化学位移的变化量Δδ与其摩尔内能的变化量ΔE满足线性关系. 以上结果表明, KCl、MgCl2与CaCl2对水分子的构造化具有促进作用, 在对水分子缔合构造的表征上, 液态水的内能变化与17O-NMR化学位移具有等效性.

关键词: 盐类, 水, 缔合构造, 氢键, 能量表征

Abstract: At a concentration of 0-1.0 mol·L-1 the effect of salts (KCl, MgCl2, and CaCl2) on the structure of water was studied from the viewpoint of energy change using differential scanning calorimetry (DSC) and the results were compared with that obtained by the analysis of the chemical shift obtained by 17O-NMR (δ(17OH2)). A linear increase in the δ(17OH2) of water and a linear decrease in the apparent activation energy (-E'/R) of water with an increase in the concentration of salt was obtained. In addition, the rate of change of δ(17OH2) and -E'/R increased as follows: KCl22. Based on a two-state model, we demonstrate that the change in δ(17OH2) of water (Δδ) is proportional to the change in molar energy of water (ΔE). These results indicate that KCl, MgCl2, and CaCl2 promote the formation of the water cluster structure and the energy change of water is equivalent to the chemical shift obtained by 17ONMR for the characterization of the water cluster structure.

Key words: Salt, Water, Cluster structure, Hydrogen bond, Energy characterization

MSC2000: 

  • O645