Detection of Adulteration of Panax Notoginseng Powder by Terahertz Technology

The combined terahertz time-domain spectroscopy (THz-TDS) and chemometric technology is used to detect the adulteration of similar substances in Panax notoginseng powder. Four kinds samples are prepared experiment, three adulterated powder adulterating with zedoary turmeric powder, wheat flour, rice respectively. values concentration from 5% 60%, interval 5%, other sample pure modeling prediction sets divided by 3 : 1 class. feature information models extracted elimination uninformative variable (UVE) method successive projection algorithm (SPA); combining back propagation neural network (BPNN), UVE-BPNN SPA-BPNN qualitative established, model’s results show that model better; classification accuracy set 95%. Then, least square support vector machine (LS-SVM) partial (PLS) establish quantitative analysis model. LS-SVM better among correlation coefficient (RP) 0.90 0.93 LS-SVM, respectively, root mean error (RMSEP) 0.072 0.068, Among for noodles, PLS better, RP 0.94 RMSEP 0.06. THz-TDS can be determine quickly, accurately, nondestructively.