摘要
交通线上方800 cm以内,空气带电粒子中大粒径粒子(迁移率段0.04～0.004 cm2/(V·s))占66.8%,正粒子占77.3%以上,其中大粒径粒子中正粒子所占比例更高.垂直方向上,空气带电粒子的分布以距离地表面300 cm高度为最高.在地表50 cm高度,绿化带对正粒子有削减作用,削减能力随粒径增大而增强,0.04～0.004 cm2/(V·s)迁移率段正粒子可削减1个数量级;对负粒子则基本无影响.高度均匀的绿化带主要影响0.04～0.004 cm2/(V·s)迁移率段正粒子分布,叶片稠密的冠层对带电粒子的削减作用远强于树干层对带电粒子的削减作用.
Within the height of about 800 cm high above traffic road, 77.3 per cent aero electro-pellets are positive, and 66.8 per cent are large with the mobility being 0.04～0. 004 cm2/（V · s）. The greatest density of aero electro-pellets is at 300 cm from the ground surface in the vertical direction. Forest belts can reduce the density of positive air ion pellets at 50 cm high,and the reducing ability of the belts increases along with increasing of the pellet＇s diameter, but the belts have no influence on the negative air pellets. For example, forest belts may reduce one magnitude of the density of positive air pellets as the mobility of the pellets is between 0.04 cm^2/（V· s） and 0. 004 cm^2/（V ·s）. The forest belts with even highness mainly have effect on the big positive air pellets the mobility of which is 0.04～0. 004 cm^2/（V · s）. The crown part of forest belts has greater ability in reducing the air pellets than the bough part of forest belts.
出处
《合肥工业大学学报（自然科学版）》
CAS
CSCD
北大核心
2005年第10期1249-1252,1259,共5页
Journal of Hefei University of Technology：Natural Science
关键词
城市
空气带电粒子
交通线
city
aero electro-pellet
traffic road
