Acquisition of a Unique and Comprehensive System for Studying Atmospheric Heterogeneous Reactions

人们发现，非均相反应对大气中的各种过程和现象（例如南极臭氧空洞）至关重要。目前，人们对对流层化学中的非均相反应的作用越来越感兴趣。将开发一种独特的实验装置，在模拟大气条件的条件下研究颗粒与气体的相互作用。该装置将包括：（1）能够产生已知尺寸分布、数量密度和组成的颗粒的系统;（2）反应室，其可以在静态或动态模式下运行，具有温度和压力控制;（3）大气压电离质谱仪，用于测量低至约1 ppb水平的各种气体;以及（4）长光程傅里叶变换红外光谱仪，用于真实的实时跟踪颗粒组成的某些方面。此外，这个新的最先进的系统将能够利用实验室现有的各种分析技术收集颗粒，进行反应后分析。 初步研究将侧重于海盐颗粒与氮氧化物的相互作用，这是正在进行的研究和日益增加的国际兴趣的主题。此外，还将研究与大气层有关的其他反应，包括固体燃料火箭发射的氧化铝颗粒的反应。质谱仪部分将提供一个重要和独特的分析工具，用于探测实验规程或对正在进行的对流层和平流层实地活动中的各种物种进行取样和分析。该系统将在扩大欧文市加州大学大气化学研究生课程方面发挥作用。*

Heterogeneous reactions have been found to be of crucial importance to various processes and phenomena in the atmosphere, such as the Antarctic ozone hole. Currently, there is increasing interest in the role of heterogeneous reactions in tropospheric chemistry. A unique experimental apparatus will be developed to study the interaction of particles with gases under conditions simulating atmospheric conditions. The apparatus will consist of: (1) a system capable of generating particles of known size distribution, number density, and composition; (2) a reaction chamber, which can be run in either a static or a dynamic mode, with temperature and pressure control; (3) an atmospheric pressure ionization mass spectrometer for measurement of a variety of gases at levels down to about 1 ppb; and (4) a long pathlength Fourier-transform Infrared Spectrometer to follow some aspects of particle composition in real time. Furthermore, incorporated into this new state-of-the-art system will be the capability of collecting particles for post-reaction analysis using a wide variety of analytical techniques available in the laboratory. Initial studies will focus on the interactions of sea salt particles with oxides of nitrogen, the subject of ongoing research and increasing international interest. Also, other reactions of atmospheric interest will be studied, including those of alumina particles emitted by solid fuel rockets. The mass spectrometer component will provide an important and unique analytical tool for probing experimental protocols or the sampling and analysis of a variety of species in ongoing tropospheric and stratospheric field campaigns. This system will play a role in expanding graduate programs in atmospheric chemistry at the University of California, Irvine.***