| The hygroscopic properties of the aerosols have a great impact of the climate change and human health effects. In this paper,we ues the fiest self-built HTMDA system(Hygroscopic Tandem Differential Mobility Analyzer) in China to study the moisture absorption characteristics on the common inorganic and organic components in the atmospheric aerosols.,by quantitative characterization of aerosol hygroscopic properties, which determine the main factors on impact of aerosols moisture absorption characteristics. We did research on calcium salt and synthetic seal salt for the first time. It was found that inorganic compounds NaCl, (NH4)2SO4 have the deliquescence point of about 75±2%, the particle sizes of NaNO3, CaCl2 and synthetic sea salt increased with the RH (relative humidity)gradually increasing, CaSO4 is as the non-hygroscopic compounds, organic compounds of oxalic acid and adipic acid have no significant increase of moisture by increasing RH.In addition, by using electron microscopy and scanning electron microscopy analysis of the 7 compounds in the morphological characteristics under different RH,the particle sizes of (NH4)2SO4, NaNO3 and synthetic sea salt change before and after absorption with growing significantly, CaSO4 and oxalic acid, adipic acid haven't grown up. By Morphological analysis we find that(NH4)2SO4, NaNO3, CaCl2 aerosols have a spherical structure, NaCl and synthetic sea salt show the crystals like cubic structure, CaSO4 aerosol particles for the irregular calcium crystal structure, while oxalic acid and adipic acid showed oval-shaped structure. Combined with laboratory simulation results, we use the platform of humidification to study the moisture absorption of the vehicle exhaust and atmospheric aerosols. By testing different types of vehicles emission of the aerosol hygroscopicity, aerosol emissions from diesel vehicles was found before and after a smog chamber reaction showing no hygroscopic growth of aerosol, emissions from petrol cars in the experiment of growth factor change before and after the smog chamber reaction. Hygroscopic properties of ambient aerosol measurement is taken in the December 8,2009 to 20, by studying the Beijing Municipal Environmental hygroscopic properties of aerosol, we find that aerosol hygroscopic growth factor is impacted by air pollution, vehicle emissions, meteorological conditions and other factors. In the case of atmospheric stability is better in urban, aerosol hygroscopic growth factor has a peak in the noon and midnight, while there is a low growth factor in the morning and evening. While the weather conditions of atmospheric stability is poor, environmental aerosol hygroscopic growth factor show low ebb at noon and peak at midnight. In addition, the less-hygroscopic aerosols components are the main part in the environmental aerosol at the paek of growth factor, low when the main account for nearly hydrophobic aerosol components. Combining elements of ambient aerosol in Beijing we found that sulfate, nitrate were the mainly elements, the aluminum from the crust was the main cation, and ammonium sulfate was one of the most inportant factors impact the hygroscopic properties of aerosol in the environment. That indicating the aerosol moisture absorption was impacted by the local and the migration of dust from the outside world and the local pollution sources. Through analysis of aerosol hygroscopic growth factor in Beijing's winter diurnal and daily changes in the environment, we can study the Beijing aerosol hygroscopic properties with aerosol radiative forcing and climate change to provide the necessary scientific basis to the country and the world research.
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