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Experimental Methods of Dust Charging and Mobilization on Surfaces with Exposure to Ultraviolet Radiation or Plasmas
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Experimental study on the space charge properties in haze events
Xiaobin Zhang1, Sen Yang1, Tianli Bo1
1Key Laboratory of Mechanics on Western Disaster and Environment, Lanzhou University, Lanzhou 730000, China.
Journal of Environmental Sciences (China)
|December 4, 2019
Summary
Haze aerosol properties were investigated, revealing charge polarity depends on fuel type and magnitude on combustion completeness. Space charge in haze differs from clear weather, influenced by PM2.5 and relative humidity, offering insights for pollution control.
Area of Science:
- Atmospheric Chemistry
- Environmental Science
- Aerosol Physics
Background:
- Haze significantly impacts global climate, ecological balance, and human health.
- Understanding space charge properties of atmospheric aerosols during haze events is crucial.
Purpose of the Study:
- To investigate space charge properties of atmospheric aerosols in haze events.
- To propose a charging mechanism for aerosols during haze.
- To differentiate haze types based on relative humidity.
Main Methods:
- Laboratory experiments on aerosol charging.
- Field observations during haze events.
- Analysis of equivalent charge-to-mass ratio (ECTM).
Main Results:
- Aerosol charge polarity is determined by fuel type; magnitude depends on combustion completeness.
- Haze aerosol space charge differs from fair weather, linked to PM2.5 and relative humidity.
- Space charge is governed by primary aerosols (low RH) or secondary reactions (high RH).
Conclusions:
- The study elucidates space charge properties of aerosols in haze events.
- Findings provide a new perspective for air pollution prevention and control.
- Haze can be classified as dry-dust-haze (<60% RH) and wet-dust-haze (60-80% RH).
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