EHMO calculations and orbital analyses of fragment;;have been performed for the formation of oxygenates in Fischer-Tropsch synthesis on the butterfly model for four different metal (Ni,Ru,Rh,Pd) catalysts supported on...EHMO calculations and orbital analyses of fragment;;have been performed for the formation of oxygenates in Fischer-Tropsch synthesis on the butterfly model for four different metal (Ni,Ru,Rh,Pd) catalysts supported on SiO2.Calculations were made for the four processes,i.e.,CO-dissociation;Coupling of CO and H to produce CHO;Insertion of CO to M-CH3;insertion of CH2 to M-CH3 On the basis of comparing the degree of CO bonds activation and the energy barriers of the foregoing processes for these four catalysts,it is concluded that Ni/SiO2 can be used as the methanation catalyst.On Ru/SiO2 and Rh/SiO2 C2-oxygenated compound can be produced (acetaldehyde),especially Rh/SiO2 is the even better catalyst,and Pd/SiO2 is a methanol synthesis catalyst.展开更多
Summarized the four main sources of CO gas on the working face based on investigation and local observation: firstly,it analyzed the mechanism that CO gas was produced by spontaneous combustion and oxygenation of gob ...Summarized the four main sources of CO gas on the working face based on investigation and local observation: firstly,it analyzed the mechanism that CO gas was produced by spontaneous combustion and oxygenation of gob residual coal;next,it illus- trated the theory that special coal seam deposits natural CO gas,and provided correlative experiment data;and then,it illustrated the reason of the CO gas in working face in- creased relatively in the course of coal cutter's shearing,according to the translation be- tween mechanism energy and inner energy and the rupture of carbon molecule side chain during coal exploitation;lastly,illustrated the reason of CO gas appearance and the rela- tively release quantity during coal mine blasting underground.We find out the source of CO gas on the working face accurately,and provide advantages for appropriate prevention and practical management measures.展开更多
Studies have been made on the source mechanism of acoustic emission produced by pitting corrosion. Methods for identifying pitting corrosion-related AE signals were proposed and the magnitude of surface displacement d...Studies have been made on the source mechanism of acoustic emission produced by pitting corrosion. Methods for identifying pitting corrosion-related AE signals were proposed and the magnitude of surface displacement due to single pitting was estimated. It is concluded that differentiation between background noise and corrosion induced genuine AE signal is possible through using plate wave acoustic emission theory combined with parameter analysis method.展开更多
文摘EHMO calculations and orbital analyses of fragment;;have been performed for the formation of oxygenates in Fischer-Tropsch synthesis on the butterfly model for four different metal (Ni,Ru,Rh,Pd) catalysts supported on SiO2.Calculations were made for the four processes,i.e.,CO-dissociation;Coupling of CO and H to produce CHO;Insertion of CO to M-CH3;insertion of CH2 to M-CH3 On the basis of comparing the degree of CO bonds activation and the energy barriers of the foregoing processes for these four catalysts,it is concluded that Ni/SiO2 can be used as the methanation catalyst.On Ru/SiO2 and Rh/SiO2 C2-oxygenated compound can be produced (acetaldehyde),especially Rh/SiO2 is the even better catalyst,and Pd/SiO2 is a methanol synthesis catalyst.
文摘Summarized the four main sources of CO gas on the working face based on investigation and local observation: firstly,it analyzed the mechanism that CO gas was produced by spontaneous combustion and oxygenation of gob residual coal;next,it illus- trated the theory that special coal seam deposits natural CO gas,and provided correlative experiment data;and then,it illustrated the reason of the CO gas in working face in- creased relatively in the course of coal cutter's shearing,according to the translation be- tween mechanism energy and inner energy and the rupture of carbon molecule side chain during coal exploitation;lastly,illustrated the reason of CO gas appearance and the rela- tively release quantity during coal mine blasting underground.We find out the source of CO gas on the working face accurately,and provide advantages for appropriate prevention and practical management measures.
基金This work was supported by the National Key Fundamental Research Project of China (G19990650).
文摘Studies have been made on the source mechanism of acoustic emission produced by pitting corrosion. Methods for identifying pitting corrosion-related AE signals were proposed and the magnitude of surface displacement due to single pitting was estimated. It is concluded that differentiation between background noise and corrosion induced genuine AE signal is possible through using plate wave acoustic emission theory combined with parameter analysis method.
