| Autor: |
R. Sologub, Yu Obvintsev, A. S. Emilenko, I. G. Granberg, Gengchen Wang, V. Kopeykin |
| Rok vydání: |
2005 |
| Předmět: |
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| Zdroj: |
SPIE Proceedings. |
| ISSN: |
0277-786X |
| DOI: |
10.1117/12.619650 |
| Popis: |
The article examines two cases of Beijing atmosphere hazing with natural aerosol reasoned by dust veils (dust haze). Air optical characteristics measured with nefelometer are presented and meteorological parameters and concentration peculiarities ofsoot and ozone for micron and sub-micron aerosol are discussed. Nefelometric measurements were carried out on FAN device which allow to measure the directed dissipation factor at angle of q and wavelength of X 42 0. 52 0. 62 rim and also degree of plane polarization at scattering angle ofp90 for 0. 42 0. 52. Aerosol probes collection is performed simultaneously for determining the aerosol mass with gravimetric method. In both cases air mass intrusion took place at nighttime and it displaced typical smog with high soot submicron aerosol carbon monoxide and carbonic acid gas concentrations. Sharp decrease of that mixtures concentration took place. At the same time high ozone concentrations could be observed. Relative soot concentration in aerosol was very low that is non typical for Benjing conditions. During dust darkness period significant inclination from typical parameters for Benjing aerosol took place. Results of comparison of nefelometric and gravimetric measurements taken at Beijing at several years show that at smog situations typical for the city a strong correlation between nefelometric aerosol concentration measurements and gravimetric ones. At dust haze periods ratios between nefelometric and gravimetric measurements changed greatly. During dust haze correlation between directional flare at 45 deg for wavelengths of 410 nm and 630 nm and degree of linear polarization at 90deg changed that allow FAN Nefelometer data observe dust aerosol transformation processes in conditions of huge megapolis effectively. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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