According to the chemiluminescence reaction mechanism of nitric oxide(NO)and ozone(O_(3)),a new cylindrical total reflection S-type optical cavity design for rapid detection of NO gas is proposed.The optical cavity model is based on the total reflection S-type structure on the inner wall of the cylinder.Optical software ZEMAX was used to simulate the optical path of the model,and software FLUENT was used to simulate and verify the structure.The comparative analysis showed that the chemiluminescence collection efficiency of the S-type optical cavity collection path was 36.6%,and the gas reaction and mixing in the S-type optical cavity model was more sufficient,and the reaction mixing stability error was 0.049,which was 2 times higher than the traditional stability error.The model is simple in structure and meets the new national standards.It provides a practical idea of design for the real-time exhaust gas detection.
A continuous spectrum water quality on-line monitoring signal processing method based on Hilbert-Huang transform(HHT) is proposed in this paper, which combines the micro-reagent water quality on-line monitoring technology of sequential injection. The modulation signal and spectrum curve of each intrinsic mode function(IMF) component of the original spectrum signal were obtained by empirical mode decomposition(EMD). The water sample data of different concentrations in the continuous spectrum on-line monitoring system was analyzed by the HHT model. The noise signal was excavated to realize the noise reduction processing, and the reconstruction of the continuous spectrum signal was realized after the noise reduction processing was completed. The research results show that this method can effectively reduce the noise of continuous spectrum signals according to different signal-to-noise characteristics of continuous spectrum, and has convenient use, fast processing speed, and high resolution in the time-frequency domain, which effectively improves the stability and accuracy of the micro-reagent continuous spectrum water quality on-line monitoring system.
