Science. 1976 Nov 26;194(4268):941-2. doi: 10.1126/science.194.4268.941.
Measurements taken 300 meters above ground level show surprisingly high concentrations of ultragiant aerosol particles both upwind and downwind of the St. Louis, Missouri, urban area. Assuming an average particle density of 2.0 grams per cubic centimeter, concentrations of particles with diameters between 5 and 55 micrometers sampled on 11 different days averaged 31 micrograms per cubic meter upwind and 55 micrograms per cubic meter downwind of the city.
地面以上 300 米处的测量结果显示,在密苏里州圣路易斯市的上风和下风方向,超巨型气溶胶颗粒的浓度都高得惊人。假设平均颗粒密度为每立方厘米 2.0 克,在 11 天的不同时间采集的直径在 5 到 55 微米之间的颗粒浓度,在上风方向为每立方米 31 微克,下风方向为每立方米 55 微克。