The Synchrotron Radiation Photoionization Mass Spectrometry Study Of Several Molecules Related With Secondary Organic Aerosol

The photoionization and dissociation mass spectrometry of β-Pinene, toluene and o-nitrotoluene at different energies were obtained firstly using the instrument of synchrotron radiation photoionization time-of-flight mass spectrometry at the beam line of atom and molecule at National Synchrotron Radiation Laboratory under the basis that the organic molecules could be ionized with a single tunable vacuum ultraviolet photon. The ionization energy and their appearance energies of those molecules were obtained through the dealing with data of the mass spectrometry. Then, the dominant dissociation channels of those molecules were discussed with the help of experimental and theoretical results. At last, the preliminary studies of the secondary organic aerosol formation from OH-initiated photo-oxidation monocyclic benzene content were performed using the instrument of thermal desorption synchrotron radiation photoionization time-of-flight aerosol mass spectrometry developed by us. Some preliminary results were obtained and the corresponding analysis of them were also performed.There are six chapters in the thesis, the main contents are:In chapter1, the significance of the research about photoionization and dissociation of the molecules related with secondary organic aerosol was explained firstly. Then, the basic concept and experimental technology about the photoionization and dissociation of molecules were explained. At last, the theory of quantum chemistry was explained.In chapter2, the development history and the range of application about synchrotron radiation were explained firstly. Then, the structure and performance about the beam line of Atom and Molecule at National synchrotron radiation laboratory were explained in detail. At last, the instrument of synchrotron radiation photoionization time-of-flight mass spectrometry was explained in detail.In chapter3, the research significance and background of β-Pinene were explained firstly. Then, the experimental method was introduced in detail. At last, the experimental results of β-Pinene were obtained and the information of the structure and energy about the β-Pinene in the dissociation process were obtained with the help of theoretical calculation. The dominant dissociation channels of β-Pinene were discussed with the help of experimental and theoretical results.In chapter4, firstly, the research significance and background of o-nitrotoluene and toluene were explained respectively. Then, the experimental results of o-nitrotoluene and toluene were obtained and the experimental results of β-Pinene were obtained and the information of the structure and energy about the β-Pinene in the dissociation process were obtained with the help of theoretical calculation. The dominant dissociation channels of o-nitrotoluene were discussed with the help of experimental and theoretical results.In chapter5, firstly, the basic concept and the impact on the climate of aerosol were explained simply. Then, the primary source of free radicals in the atmosphere and the reaction mechanism of volatile organic compounds were explained. At last, the nucleation theory of secondary aerosol and the yield of secondary organic aerosol were explained in detail. The frequently used instrument of aerosol mass spectrometer in the study of secondary organic aerosol were also explained in detail.In chapter6, the research significance about volatile organic compounds of aromatic hydrocarbon from anthropogenic source was explained simply. Then, the background of secondary organic aerosol from monocyclic benzene content was explained. At last, the study of the secondary organic aerosol formation from OH-initiated photo-oxidation monocyclic benzene content using the instrument of thermal desorption synchrotron radiation photoionization time-of-flight aerosol mass spectrometry was explained. The preliminary experimental results were obtained and the corresponding analysis of them were also performed.