广州城区大气细颗粒物粒谱分布特征分析

The analysis of the characterization of fine particle size distribution in urban area of Guangzhou

2008年10~11月,利用大气细粒子谱分析仪(FPM-I型)对广州城区5nm^10μm大气细粒子谱进行长期连续在线测量.同时,利用大气能见度仪、黑碳分析仪、气象参数仪获取了观测点的大气能见度、黑碳质量浓度和气象参数信息.颗粒物谱型分析结果表明:整个观测期内,颗粒物数浓度谱、表面积谱及体积谱均呈双峰结构.广州地区核模态(5~20nm)、爱根核模态(20~100nm)和积聚模态(0.1~1μm)粒子日平均浓度变化范围分别为1400~4300个/cm3、5000~12300个/cm3和1600~2600个/cm3.晴天和灰霾天气下颗粒物数浓度、黑碳浓度及大气能见度对比分析结果表明:广州地区大气能见度的高低受核模态和爱根核模态粒子浓度的影响较小,与积聚模态粒子浓度呈负相关关系;黑碳质量浓度峰值的出现位置与爱根核模态粒子浓度峰值位置相一致,表明爱根核模态粒子对黑碳浓度的贡献不能忽略.

Continuous online measurement of particle number size distribution in the range of 5nm^10？m were performed in Guangzhou from October to November,2008 by using fine particle meter（FPM-I）.Meanwhile,the visibility sensor,black carbon analyzer and meteorological data sensor had also been used.Particle size distribution analysis showed that number size distribution,surface size distribution and volume size distribution were all in two-peak pattern.The daily average concentration of nucleation mode（5~20nm） particles,aitken mode（20~100nm） particles,accumulation mode（100nm^1？m） particles were in the range of 1400~4300cm-3,5000~12300cm-3 and 1600~2600cm-3,respectively.The comparison of data in sunny and haze days showed that the concentration of accumulation mode particles had a negative relationship with visibility,while those of nucleation mode and Aitken mode particles had slightly influence to it.The peaks of the black carbon mass concentration and the number concentration of Aitken mode particle appeared in the same position,which means that the concentration of Aitken mode particles to the black carbon mass concentration cannot be ignored.