材料期刊网

考察太原城区10个国控点O3日浓度变化，并分析了其与相关气象因子（能见度、大气压、空气温度、空气湿度、风速和风向）的关系．研究结果表明，夏季平均O3浓度变化最大；春季O3平均浓度变化次之，冬季变化最小；全年O3平均浓度均低于国家环境空气质量的最高标准．对各国控点日O3浓度的相关性进行聚类分析，结果显示，城市新兴繁荣区和传统重工业区等人类活动频繁的区域（ Group Ⅰ）的O3浓度变化的持续时间要明显高于过渡区域（Group Ⅱ）．城区全年时间尺度上，O3均与能见度、空气温度、空气湿度和风速存在极显著的相关性（ n＝365，P＜0．001）．小波分析结果显示城区O3时间序列的变化周期为以＜4 d的短周期为主（ P＜0?05），且在6—7月与空气温度和空气湿度存在严格的线性同步变化特征，在11月则与可见度存在近似严格的线性同步变化特征．西西北风对O3浓度影响最大，全年影响频率达50％；而夏季受此影响频率高达60％，秋季西西北风和西北北风对O3浓度的影响频率相近（约40％）．

Daily surface O3 variations in Taiyuan were investigated with consideration of meteorological factors ( visibility, barometric pressure, air temperature, air humidity, wind speed and wind direction) , using the measurement data at 10 state air quality monitoring sites. In general, the highest O3 concentration variation occurred in summer, and the lowest variation occurred in winter. The annual average O3 concentration was below the maximum limit of National Ambient Air Quality Standard. The clustering results of heat map analysis showed that the relatively higher O3 concentrations occurred in high human activities areas such as the traditional heavy manufacturing zones and newly downtown zones ( GroupⅠ) , comparing with those in the transition regions ( GroupⅡ) . During the whole year, the O3 concentrations were significantly correlated with visibility, air temperature, air humidity and wind speed, respectively ( n=365, P<0.001) . The wavelet analysis revealed that the period structure of O3 concentration time series was <4 days ( P<0. 05 ) . In addition, the linear synchronous changes were shown in the relations with air temperature and air humidity in June and July. The approximate linear synchronous changes were observed between O3 concentration and visibility in November. The west?north?west wind direction had the greatest impact on O3 concentration with the annual impact frequency of 50%, especially up to 60% in summer. The west?north?west and north?north?west wind direction had similar effects on O3 concentration in autumn, with impact frequency of 40%.