A Study of Chemical Reactions in Levitated Particles

微米级的粒子被悬浮在四极阱中，同时暴露在不同水平的大气气体中。四极阱允许观测由于粒子与其气体环境组分相互作用而产生的粒子质量变化。研究的候选系统将包括硫酸液滴与氨的相互作用、氯化钠溶液吸收硫酸和硝酸蒸汽并释放氯化氢、氯化钠溶液暴露于SO2、NO2、O3或H2 O2中产生硫酸或硝酸、溶液液滴暴露于SO2中产生硫酸铵、O3和NH3、在氯化钠溶液中掺杂铁基离子的液滴并暴露于SO2和O2中生成硫酸，以及在硫酸锰颗粒表面暴露于H2O、O2、SO2和NH3中生成硫酸铵。悬浮在捕集器中的单个颗粒将暴露于含有一种或多种反应物气体的流动N2中，同时（通过光散射）监测质量和颗粒大小的变化。结果将以净变化率的形式呈现。

Particles in the micron-size range are levitated in a quadrupole trap while being exposed to varying levels of atmospheric gases. The quadrupole trap permits the observation of particle mass changes resulting from interaction of a particle with components of its gaseous environment. Candidate systems for study will include sulfuric acid droplets interacting with ammonia, the absorption by sodium chloride solutions of sulfuric acid and nitric acid vapors with release of hydrogen chloride, the production of sulfuric or nitric acid by exposure of sodium chloride solutions to SO2, NO2, O3, or H2 O2, the production of ammonium sulfate in solution droplets exposed to SO2, O3 and NH3, the production of sulfuric acid in sodium chloride solution droplets doped with iron group ions and exposed to SO2 and O2, and the production of ammonium sulfate at the surface of manganese sulfate particles exposed to H2O, O2, SO2 and NH3. Individual particles suspended in the trap will be exposed to flowing N2 containing one or more of the reactant gases while changes in mass and particle size (by light scattering) will be monitored. Results will be presented as rates of net change.