北京中关村地区气溶胶的酸性测量

为了研究大气气溶胶的酸性及其粒径分布，笔者利用自制环状扩散管和三级撞击式组合采样器采样，ｐＨ测量和傅利叶红外光谱技术测量相结合，于１９９４处冬季至１９９５年冬季在北京中关村地区进行了采样分析。结果表明，北京中关村地区气溶胶存在酸性组成，且酸性主要分布于粒径１．５μｍ以下的细粒子中，测得的细粒子最大酸度为５６．６ｎｍｏｌ．ｍ＾－３，各冬季１９９４年冬季和１９９５年夏季气溶胶酸性较强，日平均一般在５ｍ

Measurement of Aerosol Strong Acidity in Zhongguancun,Beijing

In order to study the aerosol acidity and its diameter dispersion,between the two winters of 1994 and 1995,samples in Zhongguancun district of Beijing were collected with annular denuder and three-stage impact sampling system,and analyzed by means of measurement of pH and Fourier-Transform-Infrared(FTIR) technique.It was showed that in this district,there exists in aerosol the acid composition with its distribution mainly in the fine particles and that the strongest acidity is 56.6nmol(H⁺)·m^-3 with the relatively strong aerosol acidity in the winter of 1994 and the summer of 1995.The daily average of aerosol strong acidity is usually over 5nmol(H⁺)·m^-3.HSO₄^- was directly detected and measured with FTIR technique.It was found that HSO₄^- is one of the main reasons for the acidity of aerosol,and that HSO₄^- is about 6% of SO₄^2-.The result of regression indicated there is the obvious interrelation among the aerosol acidity,SO₄^2- and NH₄⁺ in the fine particles.