北京大气PM10中水溶性氯盐的观测研究

氯盐是大气气溶胶中重要水溶性无机盐,对2004年全年北京大气可吸入颗粒中氯盐的变化进行了监测,结果表明北京大气中可溶性氯盐的年均值在(3.1±1.7)μg·m^-3,采暖期平均浓度为(4.6±2.1)μg·m^-3,非采暖期平均浓度为(2.6±1.6)μg·m^-3.最低值出现在5月,为(1.3±0.8)μg·m^-3;最高值出现在12月,为(5.8±5.3)μg·m^-3.日变化在秋冬季多为白天浓度低,晚上浓度高,夏春季多呈现上午高,下午低的特征;季节变化呈现秋冬季高,春夏季低的特点.

Water-Soluble Chloride in Aerosol PM10 in Beijing

Water-soluble chloride is one of the most important components in aerosols. The chloride in PM10 measured from January to December 2004 in Beijing was determined using a system by combing rapid collection of fine particles and ion chromatography (RCFP-IC). The results showed that the annual average concentration of water-soluble chloride at the urban area in Beijing was about (3.1 +/- 1.7) microg x m(-3); the average concentration of chloride during the heating period was (4.6 +/- 2.1) microg m(-3) while it was (2.6 +/- 1.6) microg x m(-3) during the period no heating. The lowest concentration of (1.3 +/- 0.8) microg x m(-3) appeared in May, and the highest concentration appeared of (5.8 +/- 5.3) microg x m(-3) in December. Trends of the diurnal variation of water-soluble chloride depended on seasons. In autumn and winter, the higher concentration appeared in the daytime and the lower concentration appeared at night. In spring and summer, the higher concentration appeared at forenoon and the lower appeared at afternoon. Overall, the concentration of chloride in autumn and winter was higher than in spring and summer.