A Study of the Solvent Cage Effect involved in the Oxygen Quenching of Fluorescence and the Quenching of Singlet Oxygen.

1.氧猝灭荧光：研究了正构烷烃(C2-C7)中氧对9，10-二甲基菲(DMEa)的荧光猝灭作用。通过对猝灭速率常数Kg、溶剂笼中双分子速率Kbimo和扩散速率常数Kdiff的压力和温度关系的分析，对猝灭机理进行了讨论。高温气相和高温高压下的氧猝灭荧光：研究了气相中高温氧对二甲基甲酰胺的荧光猝灭。利用自行研制的高压池，研究了DMEA在高温高压下的氧猝灭现象。根据这些结果，讨论了溶剂笼状效应。氧猝灭：(1)研究了9-乙酰基菲(^3ππ^*)在超临界乙烷和二氧化碳中三重态的氧猝灭。…门禁更严了。从猝灭速率常数k_q、T与压力和温度的关系出发，讨论了猝灭机理，包括扩散对猝灭的贡献和猝灭所涉及的溶剂笼效应。(2)研究了二苯甲酮(^3nπ^*)在超临界二氧化碳中三重态的氧猝灭与温度和压力的关系。从k_q、T的激活能和激活体积，以及单线态氧形成的量子产率，讨论了猝灭机制。温度和压力对超临界流体中单线态氧(^1Δg)寿命的影响：测量了单线态氧在液体和超临界丙烷中的寿命随温度和压力的变化，并从溶剂分子双分子猝灭速率常数Kd的活化参数和单线态氧与溶剂分子接触时的径向分布函数g(σ)σ讨论了猝灭机理。较少

1. Oxygen quenching of fluorescence :Fluorescence quenching of 9, 10-dimethylanthracene (DMEA) by oxygen in n-alkanes (C2-C7) was investigated. From the analysis of the pressure and temperature dependence of the quenching rate constant, kg, the bimolecular rate, kbimo, in the solvent cage and the diffusion rate constant, kdiff, were evaluated and the quenching mechanism was discussed.2. Oxygen quenching of fluorescence at high temperature in gas phase and at high temperature and high pressure :Fluorescence quenching of DMEA by oxygen in high temperature in gas phase was investigated. By using a high pressure cell, which was newly constructed for this work, oxygen quenching of fluorescence of DMEA at high temperature and high pressure was also investigated. From these results, the solvent cage effect was discussed.3. Oxygen quenching of the triplet states :(1) The oxygen quenching of the triplet states of 9-acetylanthracene (^3ππ^*) in supercritical ethane and carbon dioxide was investi … More gated. From the pressure and temperature dependence of the quenching rate constant, k_q^T, the quenching mechanism was discussed including the contribution of diffusion to the quenching and the solvent cage effect involved in the quenching. (2) The oxygen quenching of the triplet state of benzophenone (^3nπ^*) in supercritical carbon dioxide as functions temperature and pressure was investigated. From the activation energy and the activation volume for k_q^T, and the quantum yield of singlet oxygen formation, the quenching mechanism was discussed.4. Temperature and pressure effects on the lifetime of singlet oxygen (^1Δg) in supercritical fluids :Lifetime of singlet oxygen was measured as functions of temperature and pressure in liquid and supercritical propane, and the quenching mechanism was discussed from the activation parameters for the bimolecular quenching rate constant, kD, by the solvent molecule, and the radial distribution function, g(σ), at contact, σ, between the singlet oxygen and solvent molecules. Less