A systematic approach to the design of the conducted electromagnetic interference （EMI） filter of high-density plasma cutting power supply has been developed. Converter components have been accurately modeled, with ...A systematic approach to the design of the conducted electromagnetic interference （EMI） filter of high-density plasma cutting power supply has been developed. Converter components have been accurately modeled, with parasitic elements extracted to reveal their impacts on the EMI noises. Circuit simulations have been used to analyze and minimize the EMI noises. Conducted EMI noise measurement and filter design of this power supply have been achieved which successfully satisfy the FCC class B limits in the frequency range from 150 kHz to 30 MHz. The analyses and experimental results show that the designed filter guarantees that the required attenuation will be achieved.展开更多
In recent years,a new family of two-dimensional(2D)transition metal carbides and/or carbonitrides labeled MXenes have greatly attracted worldwide attention.Due to their unique structure and excellent properties,such a...In recent years,a new family of two-dimensional(2D)transition metal carbides and/or carbonitrides labeled MXenes have greatly attracted worldwide attention.Due to their unique structure and excellent properties,such as unusual hydrophilicity,electrical conductivity,flexibility,and pseudo-capacitance,MXenes have great potential applications in energy storage,water desalination,catalysis,electromagnetic interference shielding,transparent conductive films and so on.However,MXenes exhibit poor stability especially under oxygen-containing conditions because of the structural defects,active transition metals and termination groups,which restrain their application fields.In this review,we focus on the current research on the stability of MXenes including oxidation and thermal stability under various conditions.The mechanism is also discussed.Based on this,the methods to improve the stability of MXenes are proposed,aiming to expand the application scope.Firstly,the structure and synthesis methods of MXenes are briefly introduced.Secondly,the oxidation process and mechanism of MXenes in different environments are introduced,including gaseous,liquid,solid,UV irradiation,hydrothermal,anodic oxidation and so on.Thirdly,the thermal stability of MXenes under an oxygen-containing atmosphere,neutral atmosphere or reducing atmosphere at different temperatures is also introduced.Finally,the methods of improving the stability of MXenes including controlling the storage environment,improving the synthesis method,regulating functional terminations,chemical edge capping methods and physical packaging methods are further discussed.展开更多
基金National Natural Science Foundation of China (No. 50477009)
文摘A systematic approach to the design of the conducted electromagnetic interference （EMI） filter of high-density plasma cutting power supply has been developed. Converter components have been accurately modeled, with parasitic elements extracted to reveal their impacts on the EMI noises. Circuit simulations have been used to analyze and minimize the EMI noises. Conducted EMI noise measurement and filter design of this power supply have been achieved which successfully satisfy the FCC class B limits in the frequency range from 150 kHz to 30 MHz. The analyses and experimental results show that the designed filter guarantees that the required attenuation will be achieved.
基金National Science Fund for Distinguished Young Scholars(No.52025041)National Natural Science Foundation of China(No.51974021,51902020)+2 种基金Fundamental Research Funds for the Central Universities of NO.FRF-TP-18-045A1 and FRF-TP-19-004B2ZNational Postdoctoral Program for Innovative Talents(BX20180034)China Postdoctoral Science Foundation(Grant No.2018M641192)。
文摘In recent years,a new family of two-dimensional(2D)transition metal carbides and/or carbonitrides labeled MXenes have greatly attracted worldwide attention.Due to their unique structure and excellent properties,such as unusual hydrophilicity,electrical conductivity,flexibility,and pseudo-capacitance,MXenes have great potential applications in energy storage,water desalination,catalysis,electromagnetic interference shielding,transparent conductive films and so on.However,MXenes exhibit poor stability especially under oxygen-containing conditions because of the structural defects,active transition metals and termination groups,which restrain their application fields.In this review,we focus on the current research on the stability of MXenes including oxidation and thermal stability under various conditions.The mechanism is also discussed.Based on this,the methods to improve the stability of MXenes are proposed,aiming to expand the application scope.Firstly,the structure and synthesis methods of MXenes are briefly introduced.Secondly,the oxidation process and mechanism of MXenes in different environments are introduced,including gaseous,liquid,solid,UV irradiation,hydrothermal,anodic oxidation and so on.Thirdly,the thermal stability of MXenes under an oxygen-containing atmosphere,neutral atmosphere or reducing atmosphere at different temperatures is also introduced.Finally,the methods of improving the stability of MXenes including controlling the storage environment,improving the synthesis method,regulating functional terminations,chemical edge capping methods and physical packaging methods are further discussed.
