Research On Key Technologies Of TOC Detection Based On Ultraviolet Three-Dimensional Fluorescence Spectra

As China becames an industrialized powerful country gradually,the national economy of China flourishes.But with the rapid development of the economy,the ecological environment in China has been damaged to different degrees,the pollution of water resources is particularly serious,water safety accidents and pollution incidents occur frequently,which endanger human health seriously.So the monitoring of the water environment has become an important task.This paper is based on a large number of investigations on various methods of total organic carbon(TOC)detection in water.In order to solve the drawbacks of the traditional method,such as cumbersome analysis process,long duration,high energy consumption,and secondary pollution,the TOC concentration is analyzed quickly and quantitatively by using the difference of fluorescence spectra of the fluorescent substances in the water,And replace the high-power light source with ultraviolet UV-LED.Meanwhile,it solves the problem of collecting weak fluorescent signals.The main contents of the research are as follows:Firstly,a large number of subject-related literature is found,the research status of the application of spectroscopic detection technology at home and abroad is studied,the problems of the existing technology are analyzed,and the methods for solving the problems are proposed.Secondly,the microscopic principle of fluorescence formation and the overview of three-dimensional fluorescence spectroscopy technique are investigated,the characteristic excitation wavelength and three-dimensional fluorescence spectroscopy of fluorescence are investigated,which uses a fluorescence spectrophotometer for TOC,and the optimal center wavelength of the UV-LED array instead of continuous light source is determined by analysis.Then,fluorescence excitation experiments on the TOC standard solution are investigated,which use a UV light-emitting diode array with the selected optimal center wavelength;the fundamental theory of the least squares support vector machine algorithm for particle swarm optimization was investigated,and predictive modeling for quantitative analysis of fluorescence spectral data is explored in detail.Finally,in order to solve the problem of faint fluorescent signal acquisition,the fluorescent signals are acquires by a fluorescent system based on a single photon counting technique.A signal processing circuit based on a field-programmable gate array chip and software were designed,they detect the TOC concentration in the water body by measuring the values of photon generated by the fluorescence signal.