氢火焰离子化检测系统设计

Design of hydrogen flame ionization detection system

设计了基于氢火焰离子化检测方法的有机物检测系统。介绍了系统的工作原理,并基于此优化了系统的结构设计;根据系统的反应条件,设计了系统的控制电路;针对系统检测信号微弱、动态范围广的特点,使用跨阻放大的方法设计了量程可切换的电流检测电路,实现了大范围的微电流检测。使用甲烷标准气体测定了系统性能,实验结果表明:标准样品重复性测量相对标准偏差均小于2%,线性相关系数大于0.99。

An organic matter detection system based on hydrogen flame ionization detection method is designed.The working principle of the system is introduced firstly,and then the structural design of the system is optimized based on the principle.According to the reaction conditions of the system,the control circuit of the system is designed.In view of the weak detection signal and wide dynamic range of the system,a current detection circuit with switchable range is designed by using the method of transimpedance amplification,which realizes a wide range of micro-current detection.The performance of the system is quantified by methane standard gas,and it is shown that the relative standard deviation of standard sample repeatability measurement is less than 2%,and the linear correlation coefficient is greater than 0.99.