取样管道对分压力质谱分析的影响

THE EFFECT OF SAMPLING PIPELINE ON PARTIAL PRESSURE MASS SPECTRUM ANALYSIS

时长管道取样分压力质谱分析的物理过程和管道对分析结果的影响进行了研究。建立了扩散方程，得到了质谱室被分析气体的分压力任意时间的分析解。认为质谱室中被分析气体的分压力随时间呈复杂的指数关系。在相当长时间后，质谱室中的被分析气体的分压力趋于稳定值。由于管道效应，在质谱室中被分析气体和空气的分压力比变为Ｎ倍，这个Ｎ和气体分子的质量有关。在分析时间较短时，该比值还与质谱室的抽速、分析时间、管道长度有关。当气体趋于稳定时，可以不考虑时间和长度效应。气体趋于稳定时间ｔｃ＝ｍａｘ（３ｌ２／Ｒ０ｖπ２，２τ）。

The effect of sampling pipline and physical process on partial pressure mass spectrum analysis was studied.The diffusion equation was established and the function of analyzed gas pressure in mass spectrometer chamber with time was gained.Analyzed gas pressure is the complex exponent Increasing with time,and becoming constant after long time. As resulte of long sampling pipeline,the ratio between the analyzed gas pressure and air pressure became N times which was related to gas mass. N was also related to time and length of sampling pipeline in short time, but after long time, the effect of time and sampling pipeline length can be neglected. The gas constant time tc=max(3l2/R0π2,2τ)