[Identification of vibration characteristics in infrared spectrum of polybrominated diphenyl ethers congeners based on Br substituents].

Structure optimization and frequency calculations of 209 kinds of PBDEs homologues were carried out at the B3LYP/6-31G(d) level based on density functional theory, the known experimental parameters of 4 PBDEs congeners were compared with the calculated values, and the average analog coefficient was 0. 989. The main vibration of DE and BDE-209 which contained only H atoms or Br substituent in the benzene ring was assigned due to their less interference for various infrared spectrum vibrations.

A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach for contaminated sites management.

A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach was developed for contaminated sites management. The contaminant concentrations were simulated by a validated interval dynamic multimedia fugacity model, and different guideline values for the same contaminant were represented as a fuzzy environmental guideline. Then, the probability of violating environmental guideline (Pv) can be determined by comparison between the modeled concentrations and the fuzzy environmental guideline, and the constructed relationship between the Pvs and environmental risk levels was used to assess the environmental risk level.