Abstract The densities ρ of the binary mixture of N-methylacetamide with water have been measured in the entire composition range of the mixture liquid state at T = (278.15, 288.15, 298.15, 308.15, 323.15 and 333.15) K at atmospheric pressure (0.1 MPa). The densities were also measured for dilute aqueous solutions of N-methylacetamide (from 0.00455 to 0.05743 mol fractions) at a temperature from 274.15 to 283.15 K, with an increment of 1 K at atmospheric pressure, in order to study the effect of N-methylacetamide on the temperature of the maximum water density. These data were later used to calculate the excess molar volumes . V m E ., partial molar volumes of water V1 and N-methylacetamide V2, and to obtain the limiting partial molar volumes V i ∞ and limiting partial molar isobaric expansion of N-methylacetamide E P ,2 ∞ . The following volumetric characteristics were then obtained from these values: the shift temperature of the maximum density, Hepler’s constant, the pressure derivative of the second virial coefficient, relative volumetric parameter of hydration. The obtained parameters show the effect of N-methylacetamide on water. The study also included a comparison of these volumetric characteristics for several aqueous solutions of amides: acetamide, urea and N-methylurea. The paper also presents a comparison of these parameters at the changes in the structure of amide molecules.

中文翻译：

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在 274.15 至 333.15 K 的温度和环境压力下，水 - N-甲基乙酰胺混合物的密度测量。一些酰胺的体积特性比较

摘要 在大气压 (0.1 MPa) 下，在 T = (278.15、288.15、298.15、308.15、323.15 和 333.15) K 时，在混合物液态的整个组成范围内测量了 N-甲基乙酰胺与水的二元混合物的密度 ρ ）。还在 274.15 到 283.15 K 的温度下测量了 N-甲基乙酰胺的稀水溶液（从 0.00455 到 0.05743 摩尔分数）的密度，在大气压下增加了 1 K，以研究 N-甲基乙酰胺的影响上水密度最大的温度。这些数据后来被用来计算多余的摩尔体积。V m E ., 水V1 和N-甲基乙酰胺V2 的偏摩尔体积, 并得到N-甲基乙酰胺EP ,2 ∞ 的极限偏摩尔体积V i ∞ 和极限偏摩尔等压膨胀。然后从这些值获得以下体积特性：最大密度的转变温度、Hepler 常数、第二维里系数的压力导数、水合的相对体积参数。获得的参数显示了 N-甲基乙酰胺对水的影响。该研究还包括对几种酰胺水溶液的这些体积特性进行比较：乙酰胺、尿素和 N-甲基尿素。论文还比较了这些参数在酰胺分子结构变化时的表现。获得的参数显示了 N-甲基乙酰胺对水的影响。该研究还包括对几种酰胺水溶液的这些体积特性进行比较：乙酰胺、尿素和 N-甲基尿素。论文还比较了这些参数在酰胺分子结构变化时的表现。获得的参数显示了 N-甲基乙酰胺对水的影响。该研究还包括对几种酰胺水溶液的这些体积特性进行比较：乙酰胺、尿素和 N-甲基尿素。论文还比较了这些参数在酰胺分子结构变化时的表现。