Surface potential decay of polymers for electrical insulation can help to determine the dark conductivity for spacecraft charging analysis. Due to the existence of radiation-induced conductivity, it decays fast in the...Surface potential decay of polymers for electrical insulation can help to determine the dark conductivity for spacecraft charging analysis. Due to the existence of radiation-induced conductivity, it decays fast in the first few hours after irradiation and exponentially slowly for the remaining time. The measurement of dark conductivity with this method usually takes the slow part and needs a couple of days. Integrating the Fowler formula into the deep dielectric charging equations, we obtain a new expression for the fast decay part. The experimental data of different materials, dose rates and temperatures are fitted by the new expression. Both the dark conductivity and the radiation-induced conductivity are derived and compared with other methods. The result shows a good estimation of dark conductivity and radiation-induced conductivity in high-resistivity polymers, which enables a fast measurement of dielectric conductivity within about 600 rain after irradiation.展开更多
We study the existence and non-existence of bound states (i.e., solutions in W1,P(RN)) for a class of quasilinear scalar field equations of the for -△pu+V(x)|u|p-2u=a(x)|u|q-2u,x∈RN,1〈P〈N,mwhen the po...We study the existence and non-existence of bound states (i.e., solutions in W1,P(RN)) for a class of quasilinear scalar field equations of the for -△pu+V(x)|u|p-2u=a(x)|u|q-2u,x∈RN,1〈P〈N,mwhen the potentials V(.)≥ 0 and a(.) decay to zero at infinity.展开更多
基金Supported by the Fundamental Research Funds for the Central Universities in Nanjing University of Aeronautics and Astronautics under Grant No NS2014089
文摘Surface potential decay of polymers for electrical insulation can help to determine the dark conductivity for spacecraft charging analysis. Due to the existence of radiation-induced conductivity, it decays fast in the first few hours after irradiation and exponentially slowly for the remaining time. The measurement of dark conductivity with this method usually takes the slow part and needs a couple of days. Integrating the Fowler formula into the deep dielectric charging equations, we obtain a new expression for the fast decay part. The experimental data of different materials, dose rates and temperatures are fitted by the new expression. Both the dark conductivity and the radiation-induced conductivity are derived and compared with other methods. The result shows a good estimation of dark conductivity and radiation-induced conductivity in high-resistivity polymers, which enables a fast measurement of dielectric conductivity within about 600 rain after irradiation.
文摘We study the existence and non-existence of bound states (i.e., solutions in W1,P(RN)) for a class of quasilinear scalar field equations of the for -△pu+V(x)|u|p-2u=a(x)|u|q-2u,x∈RN,1〈P〈N,mwhen the potentials V(.)≥ 0 and a(.) decay to zero at infinity.