用同步辐射技术研究海盐颗粒物吸湿特征及其表面异相反应机制

项目名称： 用同步辐射技术研究海盐颗粒物吸湿特征及其表面异相反应机制

项目编号： No.11305242

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 曾建荣

作者单位： 中国科学院上海应用物理研究所

项目金额： 30万元

中文摘要： 大气颗粒物污染已经成为我国许多沿海大型城市面临的主要环境问题之一。由于含有多种可溶性盐分，容易吸收或失去水分并与其它大气污染物发生表面异相化学反应，海盐颗粒物（SSA）的输入将导致大量二次颗粒物的生成，从而加重沿海城市大气颗粒物污染。评估其环境影响需要了解SSA吸湿特征并明晰SSA和其它污染物相互作用的机制。本项目基于同步辐射技术拟在上海光源建立大气环境下无机盐吸湿过程的实时原位相衬成像方法从而系统研究SSA的吸湿特征。同时利用高分辨率和高灵敏度的同步辐射荧光谱（XRF）和近边吸收结构谱（XANES）分析技术，综合使用整体和单颗粒样品分析法，对SSA表面反应过程中主量和微量元素的含量、微区分布及形态分布进行高精度原位无损分析，从分子水平上揭示SSA参与大气化学进程的机理。本项目的实施可为我国沿海城市大气污染的防治提供科学依据，同时能够发展完善相关谱学技术，进一步拓展同步辐射技术的应用领域。

中文关键词： 海盐颗粒物；同步辐射；吸湿特征；异相反应；

英文摘要： Atmospheric particulate matter pollution has become one of the major environmental problems faced by many large coastal cities in China. As sea salt particles (SSA) contain a variety of soluble salt, they can easily absorb or lose moisture and react with other atmospheric pollutants via heterogeneous chemical processes on the surface. The inland transport of SSA will result in the generation of a large amount of secondary particles, thereby increasing the atmospheric particulate matter pollution coastal cities. To evaluate the environmental impact of SSA need to understand its hygroscopic characteristics and to find out the mechanism of the interaction between the SSA and other pollutants. In this project, a method using in situ x-ray phase contrast imaging (PCI) based on synchrotron radiation (SR) to investigate the hygroscopic behaviors of inorganic salt in atmospheric environment will be established and used to study the deliquescence and crystallization of SSA. X-ray fluorescence (XRF)spectroscopy and X-ray absorption near edge structures (XANES) spectroscopy with high-resolution and high-sensitivity based on SR will be used to analyze the concentration, micro-distribution and species of major and trace elements both in bulk and single SSA during the surface heterogeneous reactions. It will provide a high-pr

英文关键词： sea salt aerosol；synchrotron radiation；hygroscopic behavior；heterogeneous reaction；