Semi-insulating gallium arsenide (GaAs) photoconductive semiconductor switches (PCSS) have great potential for high voltage switching application, however, the utility is restricted by surface flashover which wouI...Semi-insulating gallium arsenide (GaAs) photoconductive semiconductor switches (PCSS) have great potential for high voltage switching application, however, the utility is restricted by surface flashover which wouId result in breakdown. In this paper, a model of photo-activated charge wave was proposed based on the theory of photo-activated charge domain (PACD) in GaAs PCSS, and moderate suppression of PACD formation by loading the semiconductor surface with dielectric material was investigated theoretically and experimentally. Current as high as 3.7 kA was obtained at 28 kV, implying that this method can effectively inhibit the surface flashover and improve the service life of DC charged GaAs PCSS.展开更多
基于甲烷气体在其特征吸收波长下光的吸收程度随浓度变化的机理和差分吸收测量方法,结合空分复用技术和长光程吸收池技术,并考虑煤矿矿井中环境的特点,复用多个气体吸收型光纤传感器.介绍了利用差分红外光谱方法测量矿井中甲烷浓度的光...基于甲烷气体在其特征吸收波长下光的吸收程度随浓度变化的机理和差分吸收测量方法,结合空分复用技术和长光程吸收池技术,并考虑煤矿矿井中环境的特点,复用多个气体吸收型光纤传感器.介绍了利用差分红外光谱方法测量矿井中甲烷浓度的光纤网络传感系统的工作原理,给出了系统的结构框图.实验表明,吸收气室光程长为20 cm时,该传感器的检测限为4.278 m g/m3,精确度和稳定性可以满足实际要求,可在不同场合进行多点在线测量.展开更多
基金supported by the Key Project of National Natural Science Foundation of China(No.50837005)the National Science Foundation of China(Nos.10876026,51107099)+3 种基金the Foundation of the State Key Laboratory of Electrical Insulation for Power Equipment (No.EIPE09203)the Natural Science Foundation of Shaanxi Province(No.2010JM7003)the Scientific Research Program Funded by Shaanxi Provincial Education Department(No.11JK0540)the Foundation for Outstanding Doctoral Dissertation of Xi'an University of Technology(105-210904)
文摘Semi-insulating gallium arsenide (GaAs) photoconductive semiconductor switches (PCSS) have great potential for high voltage switching application, however, the utility is restricted by surface flashover which wouId result in breakdown. In this paper, a model of photo-activated charge wave was proposed based on the theory of photo-activated charge domain (PACD) in GaAs PCSS, and moderate suppression of PACD formation by loading the semiconductor surface with dielectric material was investigated theoretically and experimentally. Current as high as 3.7 kA was obtained at 28 kV, implying that this method can effectively inhibit the surface flashover and improve the service life of DC charged GaAs PCSS.
文摘基于甲烷气体在其特征吸收波长下光的吸收程度随浓度变化的机理和差分吸收测量方法,结合空分复用技术和长光程吸收池技术,并考虑煤矿矿井中环境的特点,复用多个气体吸收型光纤传感器.介绍了利用差分红外光谱方法测量矿井中甲烷浓度的光纤网络传感系统的工作原理,给出了系统的结构框图.实验表明,吸收气室光程长为20 cm时,该传感器的检测限为4.278 m g/m3,精确度和稳定性可以满足实际要求,可在不同场合进行多点在线测量.