Catalytic pyrolysis of Daqing atmospheric residue on catalyst CEP-1 was investigated in a confined ffuidized bed reactor. The results show that reaction temperature, the mass ratios of catalyst to oil and steam to oil...Catalytic pyrolysis of Daqing atmospheric residue on catalyst CEP-1 was investigated in a confined ffuidized bed reactor. The results show that reaction temperature, the mass ratios of catalyst to oil and steam to oil have significant effects on product distribution and yields of light olefins. The yields of light olefins show the maxima with the increase of reaction temperature, the mass ratios of catalyst to oil and steam to oil, respectively. The optimized operating conditions were determined in the laboratory, and under that condition the yields of ethylene, propylene and total light olefins by mass were 15.9%, 20.7% and 44.3% respectively. The analysis of pyrolysis gas and pyrolysis liquid indicates that CEP-1 has good capacity of converting heavy oils into light olefins, and there is a large amount of aromatics in pyrolysis liquid.展开更多
Power relation can be revealed in discourse. Teacher power, to a large extent, is manifested through teacher talk. This paper attempts to provide an analysis of classroom language from a critical discourse perspective...Power relation can be revealed in discourse. Teacher power, to a large extent, is manifested through teacher talk. This paper attempts to provide an analysis of classroom language from a critical discourse perspective as to uncover the power hidden in teacher talk and of how language contributes to teacher power.展开更多
基金Supported by the Innovation Foundation of China National Petroleum Corporation (No. 2001 CX-38).
文摘Catalytic pyrolysis of Daqing atmospheric residue on catalyst CEP-1 was investigated in a confined ffuidized bed reactor. The results show that reaction temperature, the mass ratios of catalyst to oil and steam to oil have significant effects on product distribution and yields of light olefins. The yields of light olefins show the maxima with the increase of reaction temperature, the mass ratios of catalyst to oil and steam to oil, respectively. The optimized operating conditions were determined in the laboratory, and under that condition the yields of ethylene, propylene and total light olefins by mass were 15.9%, 20.7% and 44.3% respectively. The analysis of pyrolysis gas and pyrolysis liquid indicates that CEP-1 has good capacity of converting heavy oils into light olefins, and there is a large amount of aromatics in pyrolysis liquid.
文摘Power relation can be revealed in discourse. Teacher power, to a large extent, is manifested through teacher talk. This paper attempts to provide an analysis of classroom language from a critical discourse perspective as to uncover the power hidden in teacher talk and of how language contributes to teacher power.
