The gas-liquid equilibrium systems of N-methylmorpholine ( NMM)/ water, methydiethanolamine ( MDEA)/ water and NMM/ MDEA are studied by the standard curves of refraction index and mass percent in the experiment. 利用折光指数浓度工作曲线分别研究了N-甲基吗啉/水、N-甲基二乙醇胺/水和N-甲基二乙醇胺/N-甲基吗啉的气液平衡体系;