Study for wavelet denoising methods of laser Raman spectrum of carbendazim pesticide
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摘要: 利用激光拉曼光谱仪采集多菌灵农药标准品拉曼信号,分别采用移动平均平滑法、小波软阈值法和小波硬阈值法对光谱信号进行去噪处理,对比各方法的去噪效果。结果表明:小波硬阈值法可获得最优去噪质量,当小波基函数为sym2,尺度分解为5,阈值量化为‘Heursure’,硬阈值处理,重构光谱的信噪比最大(为60.927),均方根误差最小(为11.429)。研究表明:小波硬阈值法能有效去除多菌灵农药拉曼光谱信号的噪声,最大程度保留拉曼光谱特征信息,为食品及农产品中农药残留的拉曼光谱快速检测提供方法支持。Abstract: Raman signal of carbendazim pesticide was collected by laser Raman spectrometer. Moving- average smoothing method, wavelet soft- threshold method and wavelet hard- threshold were applied respectively to denoise the acquired Raman signals, and their denoising effects were compared.The results showed that wavelet hard- threshold could obtain the optimal denoising quality. When wavelet base function being sym2, scale decomposition being 5, the threshold quantization being ‘Heursure', hard- threshold value being processed, signal to noise ratio ( SNR) of the reconstructed spectral was maximum which was 60.927, and root mean square error ( RMSE) was minimum which was 11.429. The study showed that wavelet hard- threshold could effectively remove the noise information of the raw Raman signals of carbendazim pesticide, and saved the most number of spectra details.The study could provide a methodological support for the rapid detection of pesticide residue in food and agricultural products based on Raman spectrum.
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Keywords:
- carbendazim pesticide /
- Laser Raman spectrum /
- wavelet analysis /
- denoising
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[1] 房超, 董雷玲, 宋阳威.高效液相色谱法同步检测橙汁饮料中多菌灵、吡虫啉残留量[J].江苏农业科学, 2010, 40 (9) :295-297. [2] 郝露露, 简秋, 廖敏, 等.超高效液相色谱-串联质谱法测定番茄中多菌灵及其主要代谢物的残留[J].农药学学报, 2012, 14 (4) :429-434. [3] 刘燕德, 刘涛, 孙旭东, 等.拉曼光谱技术在食品质量安全检测中的应用[J].光谱学与光谱分析, 2010, 30 (11) :3007-3012. [4] 张丹, 王俊红.蔬菜和水果的显微激光拉曼光谱研究[J].光谱实验室, 2010, 27 (4) :1389-1392. [5] 李永玉, 彭彦昆, 孙云云, 等.拉曼光谱技术检测苹果表面残留的敌百虫农药[J].食品安全质量检测学报, 2012, 3 (6) :672-675. [6] Shende C, Inscore F, Sengupta A, et al.Rapid extraction and detection of trace Chlorpyrifos-methyl in orange juice by surfaceenhanced Raman spectroscopy[J].Journal of Food Measurement and Characterization, 2010, 4 (3) :101-107.
[7] Xie Y F, Mukamurezi G, Sun Y Y, et al.Establishment of rapid detection method of methamidophos in vegetables by surface enhanced Raman spectroscopy[J].European Food Research and Technology, 2012, 234 (6) :1091-1098.
[8] 杨桂君, 陈玉伦.一种改进小波算法及其在拉曼光谱预处理的应用[J].光谱实验室, 2010, 27 (1) :325-330. [9] 梁亮, 杨敏华, 臧卓.基于小波去噪与SVR的小麦冠层含氮率高光谱测定[J].农业工程学报, 2010, 26 (12) :248-253. [10] 郭晓霞, 杨慧中.小波去噪中软硬阈值的一种改良折衷法[J].智能系统学报, 2008, 3 (3) :222-225. [11] 马毅, 汪西原, 雍慧.小波变换去噪应用于鲜枣糖度近红外光谱检测研究[J].计算机与应用化学, 2011, 28 (3) :303-306. [12] 徐伟, 张帅, 王克家.拉曼光谱预处理中几种小波去噪方法的分析[J].应用科技, 2009, 36 (11) :27-31. [13] 周伟.基于MATLAB的小波分析应用[M].西安:西安电子科技大学出版社, 2010. [14] 吴伟, 蔡培升.基于MATLAB的小波去噪仿真[J].信息与电子工程, 2008, 6 (3) :220-229. [15] 周扬, 戴曙光, 吕进, 等.光谱预处理对近红外光谱快速检测黄酒酒精度的影响[J].光电工程, 2011, 38 (4) :54-58. [16] Jiang H, Liu G H, Mei C L, et al.Qualitative and quantitative analysis in solid-state fermentation of protein feed by FT-NIR spectroscopy integrated with multivariate data analysis[J].Analytical Methods, 2013, 5 (7) :1872-1880.
[17] 曾守桢.小波去噪及其在信号处理中的应用[D].天津:天津大学, 2007.
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