布鲁克FTIR气体分析仪在特气分析中最新技术——谱形拟合算法的定性定量

The Latest Technology of Bruker FTIR Gas Analyzer in Gas Analysis--Qualitative and Quantitative Analysis of Spectral Fitting Method

布鲁克红外气体分析仪采用谱形拟合算法对待测气体的谱形进行解析、提取和组合匹配,同时获得各组分的浓度与谱形信息。该方法区别于传统CLS、PLS仅使用特征峰积分作为浓度评判依据的方法,对特征区域的谱形进行拟合和解析,对所测光谱进行组合匹配,实现对复杂气体中目标气体与杂质的精准定性与定量分析。其特点是在朗伯比尔定律的基础上,对目标气体的特征区域内所有干扰气体同步进行峰型匹配,精准拟合每种组分的谱图及其对总谱贡献,并将所测谱图解析为目标气谱与各类杂质谱,利用红外光谱峰型唯一的特点,进而获得各类气体及其浓度信息。此外由于该方法可以实时解析水蒸气与二氧化碳对目标谱图的贡献,使得布鲁克红外气体分析仪可以在不扣任何背景的情况下,采用单通道光谱直接进行分析。相比传统CLS、PLS线性数学模型分析或非线性最小二乘法等基础型定量方式,谱形拟合算法在复杂混气,痕量气体,同系混气中的适用性更强。

Bruker FTIR gas analyzer provide a spectrum fitting algorithm to analyze,extract,combine and match the spectrum of target gas,to obtain the concentration and spectrum information of each compound.This method is different from the traditional CLS and PLS methods which only use the characteristic peak integral value as the basis for concentration evaluation,instead,it fits and analyzes the spectrum shape of the characteristic area,combines and matches the measured spectrum,realizes the qualitative and quantitative analysis of each compounds in the complex gas.The spectrum fit method based on Lambert Beer's law,the spectrum shape of all interfering gases in the characteristic area of the target gas is fitted,the spectrum of each compound and its contribution to the total spectrum is also accurately fitted.The measured spectrum is resolved into the target gas spectrum and various impurity spectrum,with the unique characteristics of the peak shape of the infrared spectrum,concentration of each compound is obtained.In addition,because this method can analyze the contribution of water vapor and carbon dioxide to the target spectrum in real time,the Bruker FTIR gas analyzer can directly analyze the single-channel spectrum without any background.Compared with basic quantification methods such as traditional CLS,PLS linear mathematical model analysis or nonlinear least squares method,the spectral fitting algorithm is more applicable to complex gas mixtures,low concentration gases,and homogeneous gas mixtures.