Chemical composition of fog water classified according to their sizes and their formation process.

雾水的化学成分根据其大小和形成过程进行分类。

基本信息

批准号：
03804024
负责人：
ISHIZAKA Yutaka
金额：
$ 0.96万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1992
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03804024/
关键词：
acidic fog pH of fog water chemical composition of fog water SO_2 HNO_3 sulfate ion nitrate ion SO_2の液相酸化エアロゾルの化学組成 HNO_3

项目摘要

In order to study the formation process of acidic fog, chemical composition of fog water was examined simultaneously with chemical analysis of gaseous and particulate materials near the top of Mt. Norikura (Height of observation site:2770m). In this experiment, fog water was classified into four size classes and sampled with a newly made string-type cloud collector, in addition to bulk fog water sampling.Acidity measurement showed that acidic fogs are often formed in the summer seasons and minimum pH of fog water reached 3.30. It was also found that change in pH is a function of the droplet size and minimum pH of the smallest droplets(mean diameter(] SY.simeq.[)3.6um) was 3.03. Main anions in fog water were sulfate and nitrate and concentration of many constituents increased generally with decreasing fog droplet size. On the other hand, chemical composition of particulate materials suggested that aerosol particles consisted mainly of ammonium sulfate. Therefore, we assumed that ammonium in fog water was originated from aerosols captured into fog droplets. It was estimated from the assumption that sulfate produced within fog droplets by absorption of sulfur dioxide exceed 50 % of sulfate in the smallest fog droplets. Based on our observations, three processes were suggested for the formation of acidic fogs: nucleation of acidic particles such as ammonium sulfate, sulfate produced in fog droplets and absorption of nitric acid vapor.

为了研究酸性雾的形成过程，同时检查了雾水的化学成分，并对诺里库拉山顶部附近的气态和颗粒物材料进行化学分析（观测地点的高度：2770m）。在该实验中，除了散装雾气水采样外，雾水被分为四个尺寸类别，并用新制成的弦型造型收集器进行采样。酸度测量表明，酸性雾通常在夏季季节形成，最小的雾水pH值是3.30。还发现，pH的变化是液滴尺寸和最小液滴的最小pH的函数（平均直径（] sy.simeq。[）3.6UM）为3.03。雾水中的主要阴离子是硫酸盐和硝酸盐，许多成分的浓度通常会随着雾滴的尺寸降低而增加。另一方面，颗粒材料的化学组成表明气溶胶颗粒主要由硫酸铵组成。因此，我们假设雾水中的铵来自被捕获到雾液滴中的气溶胶。从以下假设中估计，通过吸收二氧化硫在最小的雾液滴中超过50％的硫酸盐在雾中产生的硫酸盐。根据我们的观察结果，建议形成酸性雾的三个过程：酸性颗粒的成核，如硫酸铵，在雾滴中产生的硫酸盐和硝酸蒸气的吸收。