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Few studies have measured polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in the atmosphere. In this study,four categories of atmospheric environments, including rural (Kengting national park, Taitung county, and Yilan county), urban (north Kaohsiung city and south Taichung city), industrial (Lin-hai industrial park), and science park (Hsinchu science park) areas were investigated for their characteristics of 2,3,7,8-substituted PBDD/F and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The elevated PCDD/F I-TEQ concentrations and higher ratio of PCDFs to PCDDs in the industrial areas reveal that the metallurgical facilities, including sinter plants, electric arc furnaces, secondary aluminum smelters, and secondary copper smelters, significantly influence their surrounding atmospheric environments. The mean PBDD/F concentrations in the atmosphere of the rural, urban, industrial, and science park areas were 11, 24, 46, and 95 fg/Nm3, respectively, while the corresponding mean TEQ concentrations were 2.7, 6.4, 12, and 31 fg TEQ/Nm3, respectively. The significantly high correlation (r = 0.85, p = 0.034)found betweenthe PBDD/F and PCDD/F concentrations in the atmospheres of the industrial areas reveals that the metallurgical facilities are also the most likely PBDD/F emission sources in the industrial areas. The PBDD/F concentration in the science park area was approximately 2-fold higher than that in the industrial areas, whereas PCDD/F I-TEQ concentration in the area was only 23% of that in the industrial areas. The elevated PBDD/F concentrations in the science park areas may be attributed to the use of polybrominated diphenyl ethers as brominated flame retardants in the electrical and electronics industries, which contribute to direct PBDD/F emissions into the environment. PBDFs were all much more dominant than PBDDs in the atmosphere, and their mass fractions increase with PBDD/F concentrations.

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Traditionally, the process for converting CH 4 into syngas (CO and H 2 ) is usually carried out at high temperature with catalysts. In this study, a new approach using a lab-scale radio frequency (rf) plasma reactor is made at room temperature with a single-step process. The major factors that affected the conversion and selectivity were examined by the fractional factorial experimental design method. Experimental results indicated that the higher methane conversion was achieved at either a higher applied power or inlet O 2 /CH 4 molar ratio (R), while the simultaneous higher selectivities of H 2 and CO were obtained at a lower R. At [CH 4 ] in ) 33.3% and 4000 N/m 2 , the better operating conditions were at R ) 1 with 130 W. The methane conversion equaled 80.1%, and the selectivities of H 2 and CO reached 92.6% and 74.0%, respectively, with a H 2 /CO molar ratio of 2.5.

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