莠去津是一种广泛使用的除草剂,我国是其原药的主要生产国家.为加强工作场所莠去津暴露浓度的检测力度,保障职业接触工人身体健康,研究开发工作场所莠去津浓度的现场快速检测方法具有重要现实意义.利用自行组装的便携式近红外光谱仪,采集了实验室配置的浓度为10～1 000 mg·L-1的莠去津溶液样本光谱,并比较了多元散射校正、变量标准化、一阶导数方法、二阶导数方法及其组合等光谱预处理方法,竞争自适应重加权采样变量选择法和遗传算法等变量选择方法,偏最小二乘算法和支持向量机等回归方法对近红外光谱模型分析精度的影响.研究发现一阶导数是最佳光谱预处理方法;遗传算法优选的光谱变量表现优于竞争自适应重加权采样变量选择法;支持向量机模型表现优于偏最小二乘模型.基于遗传算法选择的16个光谱变量建立的支持向量机模型分析精度最高,其定标决定系数、验证决定系数、定标均方差、预测均方差和相对分析误差(成分浓度的标准偏差与预测均方差的比值)分别为1,099,1754 mg·L-1,2542 mg·L-1和1143,有望应用于工作场所莠去津浓度的实际检测中.该研究探讨了近红外光谱法检测工作场所莠去津浓度的可行性,相关结果对于未来类似工作的开展具有重要参考价值.%As a wildly used herbicide,Atrazine is mainly produced in China .In order to strengthen the routine detection of Atrazine exposure concentration and protect the health of occupational contact workers,it's o f great importance to develop on-site rapid detection method .A self-assembled near infrared spectrometer was used to record spectra of laboratory prepared at razine solutions with concentration range from 10 to 1 000 mg·L-1 .The in fluences of different pretreatment methods,such as multiplicative scatter correction,standard normal variate,first order derivative (D1),second order derivative and their combinations,different variable selection methods,such as competitive adaptive reweighted sampling (CARS) and genetic algorithm (GA),different regression methods,such as partial least square (PLS) and support vector regression(nu-SVR),on the model prediction accuracy were investigated .Results show that D1 is the best pretreatment method; GA obtain better results than CARS on selecting highly related spectral variables; nu-SVR model perform better than PLS mo del .The nu-SVR model constructed with 16 spectral variables selected by GA obtained the best results,whose coefficient of determination for calibration,the coefficient of determination for validation,root mean square error of calibration,root mean square error of validation (RMSEV) and residual validation deviation (defined as SD/RMSEV where SD denotes standard deviation) are 1,099,1754 mg·L-1,2542 mg·L-1 and 1143,respectively .These results in dicate near infrared spectroscopy combined with chemometrics has great potential to quantify Atrazine concentration at workplace .This research explores the feasibility of quantification Atrazine at workplace with near infrared spectroscopy for the first time,which has great reference value for similar work in the future .
展开▼
