核磁共振CPMG方法测量氯化镁水溶液浓度

Determination of Magnesium Chloride Concentration in Aqueous Solutions by NMR CPMG Sequences

配制质量分数在0~35.00%范围内的氯化镁水溶液样品,采用核磁共振的CPMG序列法测量了样品溶液的横向弛豫时间和核磁共振信号强度,通过数据作图分析了它们与氯化镁水溶液浓度的变化关系,结果表明:氯化镁水溶液的横向弛豫时间、信号强度均与质量分数有着良好的线性关系,总体上,横向弛豫时间、信号强度随质量分数的增加而减小;从而提出一套核磁共振法测量氯化镁水溶液浓度的新方法,其中,基于信号强度测量氯化镁水溶液浓度方法的相对误差小于5%。

The magnesium chloride aqueous solution with mass fraction of 0~35.00%was prepared,the signal intensity and transverse relaxation time of the solution by CPMG sequence method of NMR were measured,and the relationship between the concentration of magnesium chloride aqueous solution and them was analyzed by plotting.The results showed that the NMR signal intensity and transverse relaxation time decreased respectively with increasing concentration,and there was a deterministic linear relationship between mass concentration and them.Then,the new method to measure the concentration of magnesium chloride aqueous solution by nuclear magnetic resonance was put forward.The relative error of measuring the concentration of magnesium chloride aqueous solution based on NMR signal intensity was less than 5%.