| Ozone is a trace gase in the atmosphere, mainly distributed in the ozone layerbeyond the stratospheric. It is mainly produced by the shortwave ultravioletirradiation of sunlight and lightning ionization in nature. And in the modern world,ozone is the secondary product of the nitrogen oxides which are produced by theindustries and the exhaust of automotive. Ozone has strong oxidation and it hasgreat impact on the content of trace gases in the atmosphere; Because of the abilityof absorbing the short UV in sunlight, ozone can protect life on earth; And as ozoneis a species of greenhouse gases, it has a great impact on climate change. In recentyears, due to the discover of the polar ozone holes and as acceleratedindustrialization, the occurrence of photochemical smog on the ground frequentlyhave great hazards for the environment and human health. So it is of greatsignificance for the detection of the ozone concentrations in the environment.In this thesis, we studied the cross section of ozone, get accurate absorptioncross section of ozone via experiments. And we studied the inversion of the ozoneconcentration by UV absorption method. A conclusion was arrived that we can getgood results by select the longer interval in two different wavelengths.It was foundthat the maximum detection limit450ppm and the minimum detection limit1.36ppm in the experiment system in lab.Furthermore we studied the inversion of the ozone concentration by differentialof absorption spectroscopy method, and design a program of spectra processing. Therelationship of optic parameter OP on the concentration N was given. Byprogramming the online procedure of ozone detect, we studied the signal to noiseratio and the lowest detection limit of ozone in the gas flow and static conditions.requiring the lowest detection0.45ppm and0.48ppm, We compare the DOASmethod and UV absorption method by the inversion of ozone concentration.Respectively.We also studied the change of the absorption cross section in different pressurebroadening. And then we found there is no peak change and frequency shift of theabsorption cross section in the resonance broaden and Lorentz broaden and theresonance broadening is very weak, There is obviously broaden in253.7nm、269nm and the ranges of270-280nm、280-288nm. Finally, we find the pressurebroadening of ozone cross section has no effect on the inversion of concentration.Lately, we studied the impact of interference gas of the sulfur dioxide on theinversion of ozone concentration. It was found that the magnitude of sulfur dioxide’s differential cross section is an order lower than ozone in the range of250-280nmand have on impacts on the inversion of ozone concentration. |
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