电渗泵—流动注射在线稀释法在火焰原子吸收光谱分析高浓度样品中？…

采用电渗泵流动注射－火焰原子吸收法（ＦＩ－ＦＡＡＳ），研究了高浓度镁样品的在线稀释和分析。电渗泵在低流量时有很好的稳定性。利用控制采样时间的办法，可以准确采集微量样品，在线稀释。同时使用Ｔ型客对雾化量进行补偿，在线稀释倍数可达１０００以上，相对标准偏差〈１．５％（ｎ＝６）。通过改变采样电压（速度），载流速度和采样时间可以方便地得到不同的稀释倍数，测定速度可达１００个／ｈ样品以上。

Application of Electroosmotic Pump flow Injection On line Dilution for Extending Dynamic Range of Flame Atomic Absorption Spectrometry

On line dilution of high concentration of Mg was developed based on the electroosmotic pump flow injection flame atomic absorption spectrometry (FI FAAS).The electroosmotic pump has very good stability at low flow rate.Precise control of small sampling volume on line dilution is possible by the control of sampling time.At the same time,a more than 10000 fold dilution with a precision of better than 1.5% RSD is achieved by using the T piece for compensation.Different dilution factors can be achieved conveniently by changing the sampling voltage,carrier rate and sampling time.The sampling frequency is above 100 samples per hour.