[Three-dimensional excitation emission matrix fluorescence spectroscopic characterization of dissolved organic matter in water of coal-mining area].

Three-dimensional excitation emission matrix was applied to characterize the fluorescence properties of dissolved organic matter in various waters of Shilong coal-mining area. Fluorescence peak I (fulvic-like) and peak II (humic-like) were strong, while peak IV and peak V (protein-like) were weak or even undetected in some samples. Fluorescence peaks in various waters and different zones showed great difference in intensities and the fluorescence peaks in underground water tended to be much lower than those of surface waters. Furthermore, the fluorescence peaks of rivers and lakes were higher than those of mine drainage, and also the fluorescence peaks in coking zone and coal mining zone were higher than those in sewage-irrigated zone, or even much higher than those in farming zone. The reason may be that coal mining activities and coal industry can bring plenty of organic matter from coal to surroundings. Meanwhile, surface water would accept mine drainage, waste water of coal-washing and sewage from daily life easier than underground water, so surface water can be polluted seriously. Fluorescence peaks in waters from coal mining area are little influenced by pH of the water but can be influenced by the content of Ca2+ to water in some extent.

[Concentration and distribution characterization of polycyclic aromatic hydrocarbons in airborne particles with different sizes].

Airborne particles with different sizes were collected in 2003 at two sampling sites(urban border and suburban area) of Beijing. Compositions of polycyclic aromatic hydrocarbons were detected by GC/MS. The results show that total concentrations of 17 PAHs ranged between 0.84 and 152.23 ng/m3, in urban border area were 1.07 - 6.60 times higher than those measured in suburban area. The total concentration of PAHs increased with decreasing ambient temperature (winter > autumn > spring > summer). About 68.4% - 84.7% of PAHs were absorbed on particles having aerodynamic diameter < or = 2.0 microm. The distribution of PAHs varies with the size of the molecules. Nearly bimodal distribution was found for two- and three-rings PAHs, four- to six-rings PAHs, however, followed unimodal distribution. The overall mass median diameter (MMD) for PAHs decreases with increasing molecular weight. Higher pollution level of PAHs in wintertime is probably ascribed to domestic heating and lower ambient temperature.