The surface tension at the liquid–air interface of eight binary mixtures formed by N,N-dimethylacetamide and n-alkanols (from methanol to 1-pentanol) or 2-alkanols (from 2-propanol to 2-pentanol) was studied at three different temperatures (283.15, 298.15, and 313.15 K) and a pressure of 0.1 MPa. Surface tension deviations were also calculated. Moreover, the excess molar enthalpies for all of these mixtures were measured at T = 298.15 K and a pressure of 0.1 MPa. Both deviation and excess functions were correlated with the mole fraction by means of the Redlich–Kister equation. The surface tension deviations are found to be positive for the system containing methanol, sigmoidal for ethanol and negative for the rest of the alkanols. With regard to excess molar enthalpies, negative values are found for the system containing methanol, sigmoidal values for ethanol, and positive values for the rest of the alkanols.

中文翻译：

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N,N-二甲基乙酰胺与正烷醇或 2-烷醇的表面和量热行为

在三个条件下研究了由N、N-二甲基乙酰胺和正链烷醇（从甲醇到 1-戊醇）或 2-链烷醇（从 2-丙醇到 2-戊醇）形成的八种二元混合物的液-气界面表面张力。不同的温度（283.15、298.15 和 313.15 K）和 0.1 MPa 的压力。还计算了表面张力偏差。此外，所有这些混合物的过量摩尔焓均在T下测量= 298.15 K 和 0.1 MPa 的压力。通过 Redlich-Kister 方程，偏差和过量函数都与摩尔分数相关。发现表面张力偏差对于含有甲醇的系统是正的，对于乙醇是 S 型的，而对于其余的链烷醇是负的。对于过量的摩尔焓，含有甲醇的系统为负值，乙醇为 S 型值，其余链烷醇为正值。