Size and composition biases on the detection of individual ultrafine particles by aerosol mass spectrometry
Size and composition biases on the detection of individual ultrafine particles by aerosol mass spectrometry
复制标题
气溶胶质谱法检测单个超细颗粒的尺寸和成分偏差
DOI：
10.1021/es001323y
复制
发表时间：
2000
影响因子：
11.4
通讯作者：
M. Johnston
中科院分区：
文献类型：
--
作者：
David B. Kane and;M. Johnston
气溶胶质谱仪可以根据颗粒的大小和化学成分对其进行计数。在大多数仪器中，单个粒子用脉冲激光烧蚀以获得质谱。使用这种方法表征环境气溶胶需要了解测量过程引起的偏差。对于直径小于200nm的颗粒，检测效率取决于大小和成分。这些依赖关系来自粒子入口的传输特性和粒子被汽化和电离的固有能力。对于一系列与大气相关的试验气溶胶，确定了每种气溶胶的相对贡献。小颗粒通常比大颗粒更难检测和分析，因为它们更难以通过入口聚焦到紧密的光束中，也因为它们更难以烧蚀。由多环芳烃、硝酸铵和碱金属离子组成的颗粒……
Aerosol mass spectrometers allow particles to be counted on the basis of size and chemical composition. In most instruments, individual particles are ablated with a pulsed laser to obtain a mass spectrum. Using this method to characterize ambient aerosols requires an understanding of biases induced by the measurement process. For particles less than 200 nm diameter, the efficiency of detection is shown to be dependent on both size and composition. These dependencies arise from the transmission characteristics of the particle inlet and the intrinsic ability of a particle to be vaporized and ionized. The relative contributions of each are determined for a series of atmospherically relevant test aerosols. Small particles are generally more difficult to detect and analyze than large particles because they are more difficult to focus through the inlet into a tight beam and because they are more difficult to ablate. Particles composed of polycyclic aromatic hydrocarbons, ammonium nitrate, and alkali metal ions ...