This work concentrates on the experimental determination of the properties of ionic molecular clusters that are produced in the bipolar ionic atmosphere of a radioactivity based 241Am charger. The main scope of this study was to investigate the dependency of the ions' properties on carrier gas contaminants caused by the evaporation of trace gases from different kinds of frequently encountered tubing materials. A recently developed high resolution mobility spectrometer allows the precise determination of the ions' electrical mobility; an empirical mass-mobility relationship was used to approximate the corresponding ion masses. It was found that impurities in the carrier gas dramatically change the pattern of the ion mobility/size distribution, resulting in very different ion properties that strongly depend on the carrier gas composition. Since the ion properties control the charging process of aerosols, it was further investigated how the different ion properties affect the calculation of the charging probabilities of aerosols. The results show that despite large variations of the ions' properties, only a minor effect on the calculated charging probabilities can be found.

中文翻译：

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双极充电条件下载气污染物对气溶胶充电概率的影响

这项工作的重点是对在基于放射性的 241Am 充电器的双极离子气氛中产生的离子分子簇的特性进行实验测定。本研究的主要范围是研究离子特性对载气污染物的依赖性，这些污染物是由不同种类的常见管道材料中的痕量气体蒸发引起的。最近开发的高分辨率迁移谱仪可以精确测定离子的电迁移率；经验质量-迁移率关系用于近似相应的离子质量。发现载气中的杂质会显着改变离子迁移率/尺寸分布的模式，导致强烈依赖于载气成分的非常不同的离子特性。由于离子特性控制着气溶胶的带电过程，因此进一步研究了不同离子特性如何影响气溶胶带电概率的计算。结果表明，尽管离子的特性变化很大，但只能发现对计算的充电概率的影响很小。