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小波变换结合多维偏最小二乘方法用于近红外光谱定量分析 总被引:1,自引:0,他引:1
将小波变换和多维偏最小二乘法相结合用于近红外光谱定量校正模型的建立。首先将原始光谱进行小波变换分解,得到系列小波细节系数,通过选取一组受外界因素少、信息强的小波系数组成三维光谱阵,然后再采用多维偏最小二乘法建立校正模型。实验结果表明,该方法所建近红外校正模捌的预测能力更强,并更具稳健性。 相似文献
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自适应小波算法用于近红外光谱的多元校正 总被引:2,自引:0,他引:2
实现了一种构建自适应小波滤波器的方法,并将其用于近红外光谱数据的多元校正。该方法根据一定的目标函数,针对信号的特性自适应地构造小波滤波器。用该法构建的滤波器对烟草样品的近红外光谱进行压缩,并将压缩后的数据采用偏最小二乘法建模,实现了烟草样品常规组分的定量分析。 相似文献
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《分析科学学报》2020,(1)
采用近红外漫反射光谱分析技术,对草莓糖度进行了无损检测研究。利用便携式近红外光谱仪采集草莓样品在600~1 100 nm波段内的漫反射光谱数据。首先利用小波变换(WT)多分辨率方法对光谱数据进行去噪预处理,然后利用遗传算法(GA)优选特征波长,最后运用偏最小二乘法(PLS)建立草莓糖度的WT-GA-PLS校正模型。该模型校正集的相关系数R_C为0.9395,校正集的均方根误差RMSEC为0.1615,预测集的相关系数R_P为0.9652,预测集的均方根误差EMSEP为0.5042。与全光谱模型(FS-PLS)和小波变换模型(WT-PLS)相比,该模型预测能力更强,稳健性更优。 相似文献
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自适应蚁群优化算法的近红外光谱特征波长选择方法 总被引:2,自引:0,他引:2
为提高近红外光谱预测模型的精度和适用性,同时简化模型,提出了自适应蚁群优化偏最小二乘法优选特征波长的方法,建立不同产地苹果可溶性固形物含量混合分析模型。收集山东、陕西和新疆的富士苹果,采集3800~14000 cm"1范围的近红外光谱,并对其重要品质指标可溶性固形物含量进行测定。利用蚁群算法启发式全局搜索的特点,结合蒙特卡罗轮盘赌随机选择机制,优选苹果可溶性固形物含量的近红外光谱特征波长,然后用偏最小二乘法建立分析模型。与全光谱偏最小二乘模型和遗传偏最小二乘模型相比,蚁群优化算法选择的波长数最少,模型预测能力最强,预测的相关系数R和预测均方根误差RMSEP分别为0.9708和0.5144。研究结果表明,自适应蚁群优化算法可以有效选择近红外光谱特征波长,提高模型的稳健性和适用性。 相似文献
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提出了用近红外光谱测定端羟基环氧乙烷-四氢呋喃共聚醚(PET)的羟值,结合主成分回归和偏最小二乘法建立了PET羟值与其近红外光谱之间的关联模型。结果表明,近红外光谱法与化学分析法的测定结果一致;近红外光谱法测定PET羟值的相对误差在5%以内;利用遗传算法选择部分波长建立校正可以降低模型的预测误差。 相似文献
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以普通玉米籽粒为试验材料,在应用遗传算法结合偏最小二乘回归法对近红外光谱数据进行特征波长选择的基础上,应用偏最小二乘回归法建立了特征波长测定玉米籽粒中淀粉含量的校正模型.试验结果表明,基于11个特征波长所建立的校正模型,其校正误差(RMSEC)、交叉检验误差(RMSECV)和预测误差(RMSEP)分别为0.30%、0.35%和0.27%,校正数据集和独立的检验数据集的预测值与实际测定值之间的相关系数分别达到0.9279和0.9390,与全光谱数据所建立的预测模型相比,在预测精度上均有所改善,表明应用遗传算法和PLS进行光谱特征选择,能获得更简单和更好的模型,为玉米籽粒中淀粉含量的近红外测定和红外光谱数据的处理提供了新的方法与途径. 相似文献
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血迹的光度法测定及其在物证分析中应用 总被引:1,自引:0,他引:1
在pH 2.4的C-L缓冲介质中人血清蛋白与氯磺酚S反应生成蓝色复合络合物,其吸收峰位于635 nm波长处,摩尔吸光率(ε635)为2.49×106L·mol-1·cm7-1,算得标准工作曲线的线性回归方程为A=3.66×10-1C-0.026,相关系数为1.000,人血清蛋白质量浓度在160 mg·L-1以内呈线性关系.方法的最低检测浓度为0.25 g·L-1,基于以上结果,提出应用上述方法于物证分析中测定血迹中人血清蛋白的含量. 相似文献
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Harun Parlar 《International journal of environmental analytical chemistry》2013,93(1-2):141-158
Abstract Toxaphene, a widely and chlorinated hydrocarbon insecticide produced by chlorination of camphene, consists of a poorly defined mixture of at least 180–190 substances. Most of these conform the formulars C10H18-nCln and C10H16-nCln, where n is 6–10. Although the chromatographic behaviour of the toxaphene components is extremely similar, seven components have been isolated up to now, six of which are hepta- to decachlor derivatives of bornane. In the following work, isolation and identification of these compounds with the help of spectroscopical methods are described and their behaviour under biotic and abiotic conditions are studied. The experiments shown, that toxaphene is slowly to rapidly degraded in various environmental systems. 相似文献
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Conclusions Using a new rapid method, K2O, Na2O, CaO, MgO, Al2O3, and Fe2O3 were determined in silicates according to a single procedure, from a single sample.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1648–1655, August, 1967. 相似文献
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Residues of anti-hormones in biological materials are routinely determined at the ppb-level1 by specific detection through high-performance thin-layer chromatography with fluorimetric detection or capillary gas chromatography with electron-capture detection backed up by a selective single step extraction. 相似文献
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Sabbatini L 《Analytical and bioanalytical chemistry》2005,381(3):529-530
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A brief survey is given of the recommended procedures for the analysis of pyrites and the results of control analyses. 相似文献
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H P Thier 《Angewandte Chemie (International ed. in English)》1974,13(4):217-224
Herbicides, like other pesticides, leave undesirable residues on the treated plants. To analyze them, the plant material is extracted and the herbicidal residues are separated from the bulk of the co-extractives of natural origin, about which too little is known. Quantitative determinations at the ppm level are best performed by gas chromatography with highly sensitive, specific detectors. In food control, where the history of the sample is unknown, the herbicide residues are identified and determined quantitatively together with the residues of other pesticides. 相似文献
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G. L. Genkina M. T. Turakhozhaev R. I. Shamsutdinov T. T. Shakirov 《Chemistry of Natural Compounds》1975,10(3):339-341
Conclusions A method for the chromatophotocolorimetric determination of erysimoside in raw material is given which has been made the basis of the analytical control of its production.Order of the Red Banner of Labor Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 334–336, May–June, 1974. 相似文献