In recent years, with attention paid to global environmental problems, there have been requirements for continuous improvement of automobile fuel economy and exhaust gas purification rate. The properties of the ferrit...In recent years, with attention paid to global environmental problems, there have been requirements for continuous improvement of automobile fuel economy and exhaust gas purification rate. The properties of the ferritic stainless steels （FSS） used to make automobile parts have been improved. This paper introduces the construction of automotive exhaust systems and describes their main failure behaviors and corrosion evaluation procedures.展开更多
It is presented that eliminating and controlling the current automotive exhaust emission should be important and urgent in China, and the Chinese state emission standards have been getting stricter and stricter. Also ...It is presented that eliminating and controlling the current automotive exhaust emission should be important and urgent in China, and the Chinese state emission standards have been getting stricter and stricter. Also the present purification technologies for automotive exhaust are elucidated. It is indicated that the development and the commercialization of Rare Earth based on three way catalytic converters is pretty necessary and urgent to address the current harsh automotive exhaust emission problems in China. In addition, the future automotive exhaust purification technologies are prospected.展开更多
There are at least three obvious trends in the developments of automotive market in China: the evolution of emission standards from Euro Ⅱ to Euro Ⅲ, the demand of lean-burn gasoline engine and the time of diesel ve...There are at least three obvious trends in the developments of automotive market in China: the evolution of emission standards from Euro Ⅱ to Euro Ⅲ, the demand of lean-burn gasoline engine and the time of diesel vehicles. The latest application and advances of exhaust catalysts by Chinese researchers, using some high effcient, economical and durable methods to meet these changes in emission regulations laws and engine technologies, were described. Rare earth oxides, such as lanthana, ceria-based solid solutions and perovskite-type oxides, are widely used as excellent promoters for thermal stability, oxygen storage capacity and oxidation/reduction activity in these catalysts. Four phases in the development of the auto exhaust catalyst industry in China since the mid 1970s were reviewed. It is argued that China will become the center of global auto exhaust catalysts industry in the next decades with its economic, technical and environmental incentives, which greatly depends on the research and development of rare earth.展开更多
Our community currently deals with issues such as rising electricity costs,pollution,and global warming.Scientists work to improve energy harvesting-based power generators in order to reduce their impacts.The Seebeck ...Our community currently deals with issues such as rising electricity costs,pollution,and global warming.Scientists work to improve energy harvesting-based power generators in order to reduce their impacts.The Seebeck effect has been used to illustrate the capacity of thermoelectric generators(TEGs)to directly convert thermal energy to electrical energy.They are also ecologically beneficial since they do not include chemical products,function quietly because they lack mechanical structures and/or moving components,and may be built using different fabrication technologies such as three-dimentional(3D)printing,silicon technology,and screen printing,etc.TEGs are also position-independent and have a long operational lifetime.TEGs can be integrated into bulk and flexible devices.This review gives further investigation of TEGs,beginning with a full discussion of their operating principle,kinds,materials utilized,figure of merit,and improvement approaches,which include various thermoelectric material arrangements and utilised technologies.This paper also discusses the use of TEGs in a variety of disciplines such as automobile and biomedical.展开更多
Precious metal-support interaction plays an important role in thermal stability and catalytic performance of the automotive exhaust catalysts. The support is not only a cartier for active compotmds in catalysts but al...Precious metal-support interaction plays an important role in thermal stability and catalytic performance of the automotive exhaust catalysts. The support is not only a cartier for active compotmds in catalysts but also can improve the dispersion of precious metals and suppress the sintering of precious metals at high temperature; meanwhile, noble metals can also enhance the redox performance and oxygen storage capacity of support. The mechanism of metal-support interactions mainly includes electronic interaction, formation of alloy and inward diffusion of metal into the support or covered by support. The form and degree of precious metal-sup- port interaction depend on many factors, including the content of precious metal, the species of support and metal, and preparation methods. The research results about strong metal-support interaction （SMSI） gave a theory support for developing a kind of new cata- lyst with excellent performance. This paper reviewed the interaction phenomenon and mechanism of precious metals （Pt, Pd, Rh） and support such as A1203, CeO2, and CeO2-based oxides in automotive exhaust catalysts. The factors that affect SMSI and the catalysts developed by SMSI were also discussed.展开更多
A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit ar...A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit arrays.The gas-sensing units can actively convert the mechanical energy of gas flow into a triboelectric current.The output current signal depends on the species and concentrations of the target chemical gases(CO,NH3,NO)in the gas flow,and thus can be used as a sensing signal.The device consists of seven gas-sensing units with different Ppy derivatives.As the different sensing units respond to the gases in different ways,the device can differentiate between gas species.The working mechanism is attributed to the coupling effect between the triboelectric effect of PDMS/Ppy and the gas-sensing properties of Ppy.The device can be installed in the tailpipe of an automobile,and can thus analyze the exhaust gas in real time without the need for any external electrical power.The results of the present study spur a new research direction for the development of automotive exhaust gas monitoring systems,thus playing an important role in the detection of air pollution.展开更多
文摘In recent years, with attention paid to global environmental problems, there have been requirements for continuous improvement of automobile fuel economy and exhaust gas purification rate. The properties of the ferritic stainless steels （FSS） used to make automobile parts have been improved. This paper introduces the construction of automotive exhaust systems and describes their main failure behaviors and corrosion evaluation procedures.
文摘It is presented that eliminating and controlling the current automotive exhaust emission should be important and urgent in China, and the Chinese state emission standards have been getting stricter and stricter. Also the present purification technologies for automotive exhaust are elucidated. It is indicated that the development and the commercialization of Rare Earth based on three way catalytic converters is pretty necessary and urgent to address the current harsh automotive exhaust emission problems in China. In addition, the future automotive exhaust purification technologies are prospected.
文摘There are at least three obvious trends in the developments of automotive market in China: the evolution of emission standards from Euro Ⅱ to Euro Ⅲ, the demand of lean-burn gasoline engine and the time of diesel vehicles. The latest application and advances of exhaust catalysts by Chinese researchers, using some high effcient, economical and durable methods to meet these changes in emission regulations laws and engine technologies, were described. Rare earth oxides, such as lanthana, ceria-based solid solutions and perovskite-type oxides, are widely used as excellent promoters for thermal stability, oxygen storage capacity and oxidation/reduction activity in these catalysts. Four phases in the development of the auto exhaust catalyst industry in China since the mid 1970s were reviewed. It is argued that China will become the center of global auto exhaust catalysts industry in the next decades with its economic, technical and environmental incentives, which greatly depends on the research and development of rare earth.
文摘Our community currently deals with issues such as rising electricity costs,pollution,and global warming.Scientists work to improve energy harvesting-based power generators in order to reduce their impacts.The Seebeck effect has been used to illustrate the capacity of thermoelectric generators(TEGs)to directly convert thermal energy to electrical energy.They are also ecologically beneficial since they do not include chemical products,function quietly because they lack mechanical structures and/or moving components,and may be built using different fabrication technologies such as three-dimentional(3D)printing,silicon technology,and screen printing,etc.TEGs are also position-independent and have a long operational lifetime.TEGs can be integrated into bulk and flexible devices.This review gives further investigation of TEGs,beginning with a full discussion of their operating principle,kinds,materials utilized,figure of merit,and improvement approaches,which include various thermoelectric material arrangements and utilised technologies.This paper also discusses the use of TEGs in a variety of disciplines such as automobile and biomedical.
基金supported by National Science & Technology Pillar Program(2012BAE06B00)
文摘Precious metal-support interaction plays an important role in thermal stability and catalytic performance of the automotive exhaust catalysts. The support is not only a cartier for active compotmds in catalysts but also can improve the dispersion of precious metals and suppress the sintering of precious metals at high temperature; meanwhile, noble metals can also enhance the redox performance and oxygen storage capacity of support. The mechanism of metal-support interactions mainly includes electronic interaction, formation of alloy and inward diffusion of metal into the support or covered by support. The form and degree of precious metal-sup- port interaction depend on many factors, including the content of precious metal, the species of support and metal, and preparation methods. The research results about strong metal-support interaction （SMSI） gave a theory support for developing a kind of new cata- lyst with excellent performance. This paper reviewed the interaction phenomenon and mechanism of precious metals （Pt, Pd, Rh） and support such as A1203, CeO2, and CeO2-based oxides in automotive exhaust catalysts. The factors that affect SMSI and the catalysts developed by SMSI were also discussed.
基金supported by the National Natural Science Foundation of China (11674048)the Fundamental Research Funds for the Central Universities (N170505001 and N160502002)the Program for Shenyang Youth Science and Technology Innovation Talents (RC170269)
文摘A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit arrays.The gas-sensing units can actively convert the mechanical energy of gas flow into a triboelectric current.The output current signal depends on the species and concentrations of the target chemical gases(CO,NH3,NO)in the gas flow,and thus can be used as a sensing signal.The device consists of seven gas-sensing units with different Ppy derivatives.As the different sensing units respond to the gases in different ways,the device can differentiate between gas species.The working mechanism is attributed to the coupling effect between the triboelectric effect of PDMS/Ppy and the gas-sensing properties of Ppy.The device can be installed in the tailpipe of an automobile,and can thus analyze the exhaust gas in real time without the need for any external electrical power.The results of the present study spur a new research direction for the development of automotive exhaust gas monitoring systems,thus playing an important role in the detection of air pollution.
