中文摘要：

以醋糟有机基质为研究对象,采用便携式可见/近红外光谱仪获得基质样品的光谱信息,经过归一化和一阶微分预处理后,采用逐步回归法提取对有机基质全氮反应敏感的特征光谱,建立基于特征波长组合的线性回归模型。其中,以1 699、746、1 864和2 154 nm为特征波长的四元回归模型为最佳,其预测相关系数和预测均方根误差分别为0.933 4和1.04。结果表明,利用可见/近红外光谱技术,通过特征光谱的提取并建立相应的回归模型,可以实现对有机基质全氮含量的快速准确检测。

英文摘要：

For the purpose of developing a method for rapid detection of total nitrogen content in organic vinegar residue substrates,visible-near-infrared spectroscopy was used to collect the spectral data of the representative samples.And the spectra were pretreated by the method of first derivative after normalization.In order to choose the characteristic wavelengths for the total nitrogen content in the substrates,stepwise regression（SWR） method was applied twice.The results indicated that the characteristic wavelength was at 1 699 nm,746 nm,1 864 nm and 2 154 nm,respectively.Based on these wavelengths,a linear regression model was performed.For comparing the predictive precision of the model,the correlationship between prediction total nitrogen content and that obtained by chemical method was analyzed.It was confirmed that the multivariate equation was the best with correlation coefficient 0.933 4 and root mean squared error of prediction（RMSEP） 1.04.Therefore,it was demonstrated that visible-near-infrared spectroscopy with characteristic wavelengths selecting could be an available method for rapid detection of total nitrogen content in organic substrate.