The ultrasonic velocity (u), density (ρ) and viscosity (η) of Nicotinic acid in methanol solutions have been investigated at 288, 298 and 308 K. From these experimental measurement, thermo acoustical parameters such as acoustical impedance (Z), adiabatic compressibility (β_a), intermolecular free length (L_f), relaxation time (τ), internal pressure (π_in) and free volume (V_f) have been computed. The variation of these acoustical parameters with molar concentration and temperature indicates the existence of strong molecular interaction in the systems studied. The acoustical analysis revealed the possibility of intermolecular hydrogen bonding in the binary liquid solution of Nicotinic acid and Methanol.

中文翻译：

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不同温度下烟酸二元混合液的理化分析

烟酸在甲醇溶液中的超声速度（u），密度（ρ）和粘度（η）分别在288、298和308 K下进行了研究。通过这些实验测量，热声参数如声阻抗（Z），绝热可压缩性（β_一），分子间的自由长度（L _˚F），松弛时间（τ），内压（π_中）和自由体积（V _˚F）已经被计算出来。这些声学参数随摩尔浓度和温度的变化表明所研究系统中存在强分子相互作用。声学分析表明，烟酸和甲醇的二元溶液中存在分子间氢键的可能性。