【摘要】 分别在短波、长波近红外2个区域,以透射、反射2种方式探讨了利用近红外光谱检测腐乳盐坯中盐分含量的理论依据,试验表明,光谱吸光度随盐溶液浓度的增加逐渐降低,谱峰向短波方向漂移;在用偏最小二乘法(PLS)建模过程中,重点讨论了异常值剔除,光谱预处理,波段优化选择等。尝试了在900nm￣1300nm、1650nm￣1850nm、2150nm￣2240nm 3段光谱范围内建模,所得建模相关系数R(0.994)、建模标准差RMSEC(0.391%)、预测标准差RMSEP(0.416%)、预测集平均相对标准偏差RSD(2.27%)均好于连续全谱(833nm￣2500nm)范围的指标。另外,还得出了积分球与光纤漫反射光谱对盐分检测结果无显著性差异(p=0.01)的结论。更多还原

【Abstract】 Two methods of salt content detection in salted pehtze of sufu were studied.The methods are: transmission and reverberation in short wave and long wave infrared area by near infrared spectroscopy(NIR,833-2500 nm respectively).The results showed that the absorbance of spectra declined and the apex had an excursion to the short wave band with the increase of salt content.After eliminating outliers,pretreating spectra and optimizing the wavelengths,the models of salt in salted pehtze were calibrated by Partical least squares regression(PLS) using integrating sphere reflectance method(R = 0.994,RMSEC = 0.391%,RMSEP = 0.416%,RSD = 2.27%) Both methods do not have a significant difference(p = 0.01).更多还原