Electron-beam Analysis of Individual Aerosol Particles: Applications to Atmospheric Chemistry

该项目将使用自动电子束仪器来确定对流层气溶胶中单个颗粒的化学成分、大小和形状。这种粒子很重要，因为它们对太阳辐射平衡和大气气候稳定有影响。将从主要在北太平洋和北极地区的偏远地点获取对流层中部和行星边界层的样本，以便研究全球对流层化学的几个重要方面。由此产生的数据将能够识别组成粒子的类型，并将应用于粒子的长距离运输和北极雾霾的性质等问题。使用扫描电子显微镜和电子探针对单个颗粒进行无人值守、自动分析的方法将得到改进，以加强亚微米颗粒的常规分析。分析方法的进步与选定的气溶胶研究相结合，将有助于更好地界定颗粒源，并对对流层中的颗粒物的作用有新的认识。

The project will employ automated electron-beam instruments to determine the chemical compositions, sizes, and shapes of individual particles from tropospheric aerosols. Such particles are important because of their impact on solar radiation balance and climatic stability of the atmosphere. Samples from the mid-troposphere and planetary boundary layer will be obtained from remote sites, primarily in the North Pacific and Arctic regions, in order to study several significant aspects of global tropospheric chemistry. Resulting data will allow identification of component particle types and will be applied to problems such as long-range transport of particles and the nature of Arctic haze. Methods for unattended, automated analysis of individual particles using the scanning electron microscope and electron microprobe will be modified to enhance the routine analysis of submicron particles. Advances in the analytical methods combined with the selected aerosol studies will result in better definition of the particle sources and new insights into the role of particles in the troposphere.