通过二次回归正交设计对激光诱导击穿光谱实验参数优化建模

Optimization Modeling for Experimental Parameters of Laser-Induced Breakdown Spectroscopy by Quadratic Regression Orthogonal Design

激光诱导击穿光谱(LIBS)为多元素同时分析提供了一种简单、快速的分析工具。对LIBS多元素同时分析时实验参数优化,提出了一个"综合信背比(ISBR)"的优化目标函数。基于二次回归正交设计(QROD)构建了激光脉冲能量、检测延时、样品距透镜距离、积分时间这些因素对目标函数影响的多因素模型。结果表明,目标函数可以顾及多条谱线性能,为多元素同时分析提供参数优化的依据。利用QROD方法建立多因素模型,可以获得比单因素逐个优化更优的实验条件,并大大减少了实验次数。

Laser-induced breakdown spectroscopy （LIBS） offers a simple and fast tool for multi-element simultaneous analysis. For optimizing experimental factors in LIBS multi-element simultaneous analysis, an objective function, named ＂integrated signal-to-background ratio （ISBR）＂, is proposed. The coupling influences of the laser energy, measuring time delay, distance between lens and samples, and integration time on the objective function are modeled based on the quadratic regression orthogonal design （QROD）. Experimental results indicate that the objective function can contain multiple spectral properties and can provide a standard for the selection of experimental conditions in multi-element analysis. By the multi-factor model built through the QROD, more optimal experimental parameters can be obtained and less experimental numbers are needed than by the single factor experiments.