Based on the necessity of three dimensional modeling with computer in teaching reform, this paper is the summarization of reform practice of teaching engineering drawing in our institute. The teaching reform begins wi...Based on the necessity of three dimensional modeling with computer in teaching reform, this paper is the summarization of reform practice of teaching engineering drawing in our institute. The teaching reform begins with three dimensional modeling that used computer instead of board. On the basis of target of teaching reform, set of teaching content, arrangement of class hour and teaching method, the research of teaching practice have been done, and very good effects in teaching of engineering drawing have been achieved.展开更多
In the purification process of automobile exhaust,existing water plays an important role as an oxidant,which converts CO and hydrocarbons（HCs） by the water-gas shift（WGS） and the steam reforming（SR） reactions,re...In the purification process of automobile exhaust,existing water plays an important role as an oxidant,which converts CO and hydrocarbons（HCs） by the water-gas shift（WGS） and the steam reforming（SR） reactions,respectively,especially at high temperatures.Meanwhile it is major component of the exhaust which can affect significantly the thermal stability of the three-way catalyst.Activity experiments were carried out close to the real operation conditions（GHSV,concentration,etc.） with a Pd/Ce0.67Zr0.33O2 catalyst supplying information on the CO and C3H8 oxidation reactions in feedstream formed by different reactant combinations.The obtained results showed that the activity of the CO and C3H8 oxidation was promoted by the addition of steam due to the WGS and SR reactions.The WGS and SR reaction were competitive under oxygen-lean conditions.The kinetic analysis was considered for WGS and SR reactions.展开更多
Ceria-zirconia-alumina （CZA） solid solution was prepared by sol-gel method in the present study. 0.5 wt.% Pd supported on CZA was prepared by incipient wetness impregnation. The steam effects for CO and C3H8 oxidati...Ceria-zirconia-alumina （CZA） solid solution was prepared by sol-gel method in the present study. 0.5 wt.% Pd supported on CZA was prepared by incipient wetness impregnation. The steam effects for CO and C3H8 oxidation, three-way catalytic activity and stoichiometric window property were studied. The light-off temperature of the CO oxidation reaction shifted to a lower temperature due to the water-gas shift （WGS） reactions. The oxidation of C3H8 was enhanced due to the steam reforming （SR） reactions. The steam promoted the C3H8 oxidation and NO reduction in three-way catalytic reaction. The amplitude of stoichiometric window was amplified by the addition of water to the feed stream.展开更多
基金Supported by Beijing City Institution of Higher Learning Talent Education Program Project Foundation (PHR200906213PHR201007234)
文摘Based on the necessity of three dimensional modeling with computer in teaching reform, this paper is the summarization of reform practice of teaching engineering drawing in our institute. The teaching reform begins with three dimensional modeling that used computer instead of board. On the basis of target of teaching reform, set of teaching content, arrangement of class hour and teaching method, the research of teaching practice have been done, and very good effects in teaching of engineering drawing have been achieved.
基金supported by the National High-Tech Research and Development Program of China(2009AA064803)
文摘In the purification process of automobile exhaust,existing water plays an important role as an oxidant,which converts CO and hydrocarbons（HCs） by the water-gas shift（WGS） and the steam reforming（SR） reactions,respectively,especially at high temperatures.Meanwhile it is major component of the exhaust which can affect significantly the thermal stability of the three-way catalyst.Activity experiments were carried out close to the real operation conditions（GHSV,concentration,etc.） with a Pd/Ce0.67Zr0.33O2 catalyst supplying information on the CO and C3H8 oxidation reactions in feedstream formed by different reactant combinations.The obtained results showed that the activity of the CO and C3H8 oxidation was promoted by the addition of steam due to the WGS and SR reactions.The WGS and SR reaction were competitive under oxygen-lean conditions.The kinetic analysis was considered for WGS and SR reactions.
基金Project supported by National High-Tech Research and Development Program of China(2011AA03A405)the Key Program of TianjinNatural Science Foundation(09JCZDJC26600)
文摘Ceria-zirconia-alumina （CZA） solid solution was prepared by sol-gel method in the present study. 0.5 wt.% Pd supported on CZA was prepared by incipient wetness impregnation. The steam effects for CO and C3H8 oxidation, three-way catalytic activity and stoichiometric window property were studied. The light-off temperature of the CO oxidation reaction shifted to a lower temperature due to the water-gas shift （WGS） reactions. The oxidation of C3H8 was enhanced due to the steam reforming （SR） reactions. The steam promoted the C3H8 oxidation and NO reduction in three-way catalytic reaction. The amplitude of stoichiometric window was amplified by the addition of water to the feed stream.
