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The thermal decomposition behavior of fire retardant viscose fiber and viscose fiber were studied by thermogravimetric analysis (TGA) under air atmosphere at heating rates of 10, 20, 30 and 40 o C/min. The activation energy and pre-exponential factor were calculated by using the Kissinger method, Flynn-Wall-Ozawa (FWO) method and Satava-Sestak method. The results show that the activation energy for the fire retardant viscose fiber calculated by Kissinger and FWO method was 102.51kJ/mol and 103.73kJ/mol, respectively. The activation energy for viscose fiber calculated by Kissinger and FWO method was 103.58 kJ/mol and 104.83kJ/mol, respectively. The kinetic mechanism function of fire retardant viscose fiber was G(α) = [(1+α) 1/3-1] 2 following a kinetic model of three-dimensional diffusion and the kinetic mechanism function of viscose fiber was G(α) = α 3/2 following the power function rule.

, with an average of 10249 fg m 3 . The international toxic equivalents (I-TEQ) value of that was 61.81182 fg m 3 , with an average of 235 fg m 3 , which was comparable to those in the other urban locations around the world. It was found that the Cl 48 DD/Fs appeared to be present mainly in the particle phase during winter, spring and autumn, while during summer which were dominantly in gas phase. The ratio of Cl 48 DD/Fs present in particle phase increased with the increasing level of chlorination. The concentrations of PCDFs and PCDDs decreased with the increase of chlorinated level, while the concentrations of 2,3,7,8-PCDDs congeners increased with the increase of chlorination level. The homolog profiles of the concentrations of PCDFs presented were higher than those of the PCDDs, which indicated the PCDD/Fs pollution source of the air in Dalian was characteristic for thermal source pollution. The correlation analysis of meteorological parameters with the concentrations of Cl 48 CDD/Fs was conducted using SPSS packages, and it was found that the ambient temperature and atmospheric pressure were important factors influence the concentration of PCDD/Fs in the air. The respiratory risk and intake dioxins of the residents around the sampling sites were studied in the paper. It was found that Junge-Pankow model was much more accurate in predicting the gas-particle partitioning behavior of PCDD/Fs homologues during winter, while the Harner-Bidleman model shows better agreement with the measured data during winter and summer.PCDD/Fs, urban air, gas-particle partitioning, Dalian

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