Owing to GPS clock, which has no accumulative error, and quartz oscillator, which is very stable, the time counting value is obtained without delay via hardware by combining high speed sampling and PPS ( Pulse Per-Second)-snapping. 利用GPS时钟无累计误差和高精度晶振频率稳定性高的特点,并将高速采样与秒脉冲捕捉有机结合,通过硬件方式无延时地捕捉秒脉冲以获取精确的时间计数值。
The accumulative sampling method has more advantages over the instantaneous method in measuring Cl~-and H_2S for the process is simple, tolerance small and data reliable and precise. 而累计采样法(连续)对Cl、H2S进行测定时,程序简单、误差小、数据可靠、准确。此方法明显优于瞬时法。