有机气溶结构的大小依赖性
Daniel P Veghte1, Muhammad Bilal Altaf, Miriam Arak Freedman
1Department of Chemistry, The Pennsylvania State University , 104 Chemistry Building, University Park, Pennsylvania 16802, United States.
Journal of the American Chemical Society
|October 16, 2013
概括
气溶颗粒相位分离,对于大气化学和气候至关重要,取决于颗粒大小. 较小的粒子 (<170-270 nm) 保持不分离,而较大的粒子呈现相位分离.
科学领域:
- 大气化学 大气化学
- 气候科学 气候科学
- 材料科学 材料科学 材料科学
背景情况:
- 不同质的大气化学和气候影响受到气溶颗粒的组成和结构的影响.
- 了解气溶颗粒中的化合物的内部排列是预测它们对环境的影响的关键.
研究的目的:
- 为了研究模型有机气溶颗粒的相分离行为.
- 为了确定颗粒大小对混合硫酸和有机酸气溶的内部结构的影响.
主要方法:
- 使用冷传输电子显微镜 (cryo-TEM) 可视化气溶颗粒的内部结构.
- 检查的模型是有机气溶,由硫酸与酸或皮梅酸混合而成.
主要成果:
- 在酸混合物中小于170nm的粒子和在pimelic酸混合物中小于270nm的粒子中没有观察到相分离.
- 较大的气溶颗粒 (酸≥170nm,酸≥270nm) 呈现出分相,部分包裹的结构.
结论:
- 气溶颗粒相位分离非常依赖于颗粒大小.
- 尺寸依赖的相位分离对气溶气候相互作用和大气化学模型有重大影响.
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