| Natural emitted terpenes are volatile organic compounds that are sweat-smelling. Most terpenes are structured with isoprene-like units. Terpenes are mainly emitted from forest trees, flowers and grass. The dominating species of natural emitted terpenes areα-pinene,β-pinene, limonene and linalool. In the lower troposphere terpenes can react fast with OH radical, ozone, NO3 radical and ground state Oxygen atom. These reactions may contribute to the occurring of aerosols, peroxides(hydrogen peroxide and organic peroxide), Carbon cycle (mainly CO), acid rain (organic acids, NO3- and SO42-) and active radicals such as OH radical.In this thesis we made systemic laboratorial simulation of the atmospheric reactions ofβ-pinene, using LP-FTIR combined with GC/MS and HPLC. The purpose and the emphasis were to analyze the products occurring in the atmospheric reactions ofβ-pinene and to make clear the thorough kinetics of these reactions.We got the standard gas-phase infra-red absorption spectra of several monoterpenes includingβ-pinene and related gas-phase oxidation products. We reported the absorption coefficients of the characteristic peaks for the first time. We obtained the rate constants of the gas-phase reaction ofβ-pinene with O3 and the gas-phase reaction ofβ-pinene with OH radical at room temperature, using relative rate constant method. The values were 1.48×10-17 cm3 molecule-1 s-1 and 7.82×10-11 cm3 molecule-1 s-1 respectively. The satisfied results validated the feasibility and reliability of the LP-FTIR technology in our lab.We tailed in situ the thorough process of the gas-phase reaction ofβ-pinene with ozone, using LP-FTIR. The qualitative analysis result figured out that the main products in the gas-phase reaction ofβ-pinene with ozone are nopinone, formaldehyde and carbon dioxide. Formic acid might occur under certain condition. Under our experimental conditions the molecular transformation ratio of nopinone vs.β-pinene was 0.22. The molecular transformation ratio of formaldehyde vsβ-pinene decreased while the temperature increased, and it reached maximum when the initial concentrations ofβ-pinene and ozone were nearly the same. We analyzed the products mixture of the gas-phase reaction ofβ-pinene with ozone, using GC/MS and confirmed nopinone as the main product of the reaction. No other large carbonyls were found in our experiments. We analyzed the occurring of peroxides in the gas-phase reaction ofβ-pinene with ozone, using HPLC combined with wriggling pump sampling technique. The qualitative analysis result figured out that about 56 sorts of peroxides including hydrogen peroxide and methyl hydroperoxide occurred in the gas-phase reaction ofβ-pinene with ozone. Under our experimental conditions the molecular transformation ratio of hydrogen peroxide and methyl hydroperoxide vsβ-pinene were 0.023 and 0.013 respectively. We studied the products of the liquid-phase reaction ofβ-pinene with ozone, using GC/MS, and studied the kinetics of the reaction. The qualitative analysis result figured out that the main products in the liquid-phase reaction ofβ-pinene with ozone was nopinone, and nopinone did not react prominently with ozone. We also found some compounds with high molecular weight. We speculated that they were some sorts of compounds bearing pinene-like skeletons according to their MS spectra, but no definite conclusion was made. The yield of nopinone was 46% according to the quantitative analysis of TIC spectra.We synthesized methyl nitrite in our lab. We determined the concentrations of OH radicals induced in the CH3ONO/Air system and CH3ONO/NOx/Air system under blacklight, using toluene as the tracer reagent by chemical capturing method. The results showed that the concentrations of...
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