中文摘要：

以纳米二氧化钛（TiO2）光催化降解甲醛，使用2-甲基-2-亚硝基丙烷（2-methyl-2-nitroso-propane，MNP）作为自旋捕截剂（spin trap，ST），研究了反应过程中的自由基中间体，得到了一种新的自旋加合物（spin adduct，ST-R）．电子顺磁共振（Electron Paramagnetic Resonance，EPR）的结果表明，甲醛在水溶液中降解的反应中间体为·CH（OH）2，并提出了一种新的降解机理．

英文摘要：

Formaldehyde was degraded with photo-catalysis by nano-titanium dioxide （TiO2） and 2-methyl- 2-nitro-propane （MNP） was used as a spin trap （ST）. The radical intermediates in the process of reaction were studied and a new spin adduct （ST-R） was obtained. The results of electron paramagnetic resonance （EPR） indicated that the intermediate of formaldehyde degradation in aqueous solution was ,CH（OH）2. A new degradation mechanism was proposed.