摘要
质谱分析中常存在CO+(m/z=28)和N2+(m/z=28)之间的相互干扰,所以同时分析CO和N2时,多采用C+(m/z=12)和N+(m/z=14)分别作为CO和N2的分析线。但实验发现,一定含量的CO++(m/z=14)可能对N+(m/z=14)产生干扰,即在相同实验条件下测定含有CO和N2的气体时N+(m/z=14)处的离子强度将由CO++和N+共同组成,从而影响到N2的检测。针对上述问题考察了CO++对N+干扰情况并建立了相应的干扰校正数学模型。首先通过使用不同含量的CO标准气体建立了CO++和C+之间的离子强度方程,得到二者关系曲线,据此可以计算出CO++的含量,从而得到N+的准确含量,进而得到样品中N的含量。在自有发明专利的脉冲熔融飞行时间质谱元素测定仪上使用所建立的干扰校正模型分析金属中的O和N,尤其是在分析金属中高含量O的样品时取得明显效果。方法也可用于工业过程中在线检测CO和N2。
The mutual interference of CO ＋（m / z=28） and N 2 ＋（m / z=28） usually existed in mass spectrometric analysis.Therefore,C ＋（m / z=12） and N ＋（m / z=14） were commonly used as the analytical lines of CO and N 2 in the simultaneous analysis of CO and N 2.It was found that,however,certain amount of CO ＋＋（m / z=14） possibly had interference with N ＋（m / z=14）.In other words,during the determination of gas containing CO and N2under same experimental conditions,the ionic intensity at N ＋（m / z=14） would be comprised of CO ＋＋ and N ＋ jointly,influencing the detection of N2.Based on the problem above,the interference of CO ＋＋ to N ＋ was investigated.The corresponding mathematical correction model was established.Firstly,various amounts of CO standard gas were used to establish the ionic intensity equation between CO ＋＋ and C ＋ to obtain the relationship curve.Secondly,the content of CO ＋＋ could be calculated,so the accurate content of N ＋ could be obtained.Then,the content of N in sample could be obtained.The established correction model was used on pulse melting time-of-flight mass spectrometer with own invention patent to analyze O and N in metal.The effect was significant especially for the analysis with the existence of high content O in metal.This method could be also applicable for the on-line determination of CO and N 2 in industrial process.
出处
《冶金分析》
CAS
CSCD
北大核心
2013年第3期1-8,共8页
Metallurgical Analysis
基金
科技部创新方法专项(科11141300)
关键词
质谱干扰
校正方法
一氧化碳
氮
同时测定
mass spectral interference
correction method
carbon monoxide
nitrogen
simultaneous analysis
