Design And Application Of Experiment System For Three-dimensional Fluorescence Analysis

With the development of social economy, the pollution of mineral oil in water caused by humanbeings is becoming increasingly serious, so it is quite important to detect the content of mineral oil in water.The three-dimensional fluorescence analysis is one of the most widely used methods in the detection of mineral oil in water, it is based on the property that the mineral oil contained in water has the characteristic of fluorescence, and it also can qualitatively and quantitatively analyze the sample solution by detecting the fluorescence signal excited by the excitation light source.In order to improve the organic concentration prediction accuracy of the fluorescence detection instrument, the three-dimensional fluorescence detection experiment system was designed and constructed, which improved the light path of the excited light source. The system mainly consists of excitation light source, excitation monochromator, sample room, emission monochromator, photoelectric detector, computer control system and so on. The wavelength detection accuracy of the system can reach ±nm7.0 after it added a structure that can real-time feedback the rotation angle of the grating,while the wavelength detection accuracy is ±nm7.0 before the structure is added. Obviously increasing the real-time feedback structure of the grating rotation angle can improve the performance of the whole system.Applied the improved experiment system to scan the sample solution, we obtained the threedimensional fluorescence spectra and their contour spectra of the pure kerosene, pure 0# diesel, pure 97#gasoline and pure CCl4, and mastered their spectral characteristics. There are 30 groups of different concentrations sample solution detected in the experiment, and the 1~16 groups are calibration samples, the 17~30 groups are prediction samples. The average recovery rates(%) of the mixed sample solutions that contained three organic compounds are as follows, the kerosene is 31.756.88 ±, the 0# diesel is 11.389.91 ±, and the 97# gasoline is 26.1626.84 ±. Although the prediction results of the sample solution concentrations are different from the actual solution concentrations, the deviation value is within the proper rage. The results show that this system can be used to predict the concentrations of the three organic compounds in the mixed solution, and it's highly reliable.