西安市典型功能区空气小离子浓度分布特征与评价

Distribution Characteristics and Assessment of Minor Air Ion Concentration in Typical Functional Areas of Xi'an

利用DLY-2G型空气离子测量仪对西安市休闲度假区、文教区、交通区和工厂区等4个典型功能区夏季与秋季空气小离子的数密度进行了实测,研究了西安市不同功能区空气小负离子与小正离子的时空变化规律,并对不同功能区的空气质量进行评价。结果表明,西安市典型功能区空气小离子的数密度日变化显著且各有特点,主要呈单峰或双峰形式;不同功能区夏季空气小离子的数密度普遍比秋季高;各功能区空气小离子的数密度分布差异很大,休闲度假区小负离子的数密度在夏秋两季均明显高于其他功能区;与空气离子单极系数评价指标相比,空气离子评价指数能更准确地反映区域空气清洁度。

Number density of minor air ion in four typical functional areas（leisure resort,district of culture and education,traffic area and factory district） of Xi＇an was measured in summer and autumn by DLY-2G air ion monitor.Spatial-temporal variations of number density of minor air cation and anion in different functional areas were studied,and then air quality was assessed.The result showed that daily variations of number density of minor air ion in typical functional areas of Xi＇an were significant and diverse from each other,and appeared one-peak or double-peak curve;number density of minor air ions was higher in summer than that in autumn;distribution of number density of minor air ions was very different among the functional areas,number density of minor air anion was highest in leisure resort;compared with the method of polarity ratio,air ion assessment index was more reasonable to indicate air cleanliness.