Approach for measuring the chemistry of individual particles in the size range critical for cloud formation.
Approach for measuring the chemistry of individual particles in the size range critical for cloud formation.
复制标题
测量对云形成至关重要的尺寸范围内单个颗粒的化学性质的方法。
DOI：
10.1021/ac103152g
复制
发表时间：
2011
影响因子：
7.4
通讯作者：
Prather,KimberlyA
中科院分区：
文献类型：
--
作者：
Zauscher,MelanieD;Moore,MeaganJK;Lewis,GregoryS;Hering,SusanneV;Prather,KimberlyA
气溶胶粒子，尤其是直径在50至200纳米之间的粒子，作为凝结水和形成云滴的核，对气候产生了强烈的影响。然而，能够测量该尺寸范围内颗粒组成的分析方法很少，特别是在单个颗粒水平上，这限制了我们对云凝结核（CCN）组成的了解，从而限制了我们对气溶胶对气候影响的理解。为了更深入地了解这个尺寸范围内的颗粒，我们开发了一种将生长管（GT）与超细气溶胶飞行时间质谱仪（UF-ATOFMS）耦合的方法，这种组合可以原位测量小至38纳米的单个颗粒的组成。生长管利用水将颗粒生长到更大的尺寸，这样它们就可以被UF-ATOFMS光学检测到，将尺寸范围扩展到100纳米以下，而颗粒组成没有明显的变化。为了进一步了解气溶胶化学和来源的时间变化，使用GT-UF-ATOFMS进行了为期3天的在线连续测量。
Aerosol particles, especially those ranging from 50 to 200 nm, strongly impact climate by serving as nuclei upon which water condenses and cloud droplets form. However, the small number of analytical methods capable of measuring the composition of particles in this size range, particularly at the individual particle level, has limited our knowledge of cloud condensation nuclei (CCN) composition and hence our understanding of aerosols effect on climate. To obtain more insight into particles in this size range, we developed a method which couples a growth tube (GT) to an ultrafine aerosol time-of-flight mass spectrometer (UF-ATOFMS), a combination that allows in situ measurements of the composition of individual particles as small as 38 nm. The growth tube uses water to grow particles to larger sizes so they can be optically detected by the UF-ATOFMS, extending the size range to below 100 nm with no discernible changes in particle composition. To gain further insight into the temporal variability of aerosol chemistry and sources, the GT-UF-ATOFMS was used for online continuous measurements over a period of 3 days.