Manganese dioxide （MnO2） was prepared using the ultrasonic method. Its electrochemical performance was evaluated as the cathode material for a high voltage hybrid capacitor. And the specific capacitance of the MnO2 ...Manganese dioxide （MnO2） was prepared using the ultrasonic method. Its electrochemical performance was evaluated as the cathode material for a high voltage hybrid capacitor. And the specific capacitance of the MnO2 electrode reached 240 F·g^-1. The new hybrid capacitor was constructed, combining A1/Al2O3 as the anode and MnO2 as the cathode with electrolyte for the aluminum electrolytic capacitor to solve the problem of low working voltage of a supercapacitor unit. The results showed that the hybrid capacitor had a high energy density and the ability of quick charging and discharging according to the electrochemical performance test. The capacitance was 84.4 μF, and the volume and mass energy densities were greatly improved compared to those of the traditional aluminum electrolytic capacitor of 47 μF. The analysis of electrochemical impedance spectroscopy （EIS） showed that the hybrid capacitor had good impedance characteristics.展开更多
In this paper,we present a QP-free algorithm without a penalty function or a filter for nonlinear semidefinite programming.At each iteration,two systems of linear equations with the same coefficient matrix are solved ...In this paper,we present a QP-free algorithm without a penalty function or a filter for nonlinear semidefinite programming.At each iteration,two systems of linear equations with the same coefficient matrix are solved to determine search direction;the nonmonotone line search ensures that the objective function or constraint violation function is sufficiently reduced.There is no feasibility restoration phase in our algorithm,which is necessary for traditional filter methods.The proposed algorithm is globally convergent under some mild conditions.Preliminary numerical results indicate that the proposed algorithm is comparable.展开更多
文摘Manganese dioxide （MnO2） was prepared using the ultrasonic method. Its electrochemical performance was evaluated as the cathode material for a high voltage hybrid capacitor. And the specific capacitance of the MnO2 electrode reached 240 F·g^-1. The new hybrid capacitor was constructed, combining A1/Al2O3 as the anode and MnO2 as the cathode with electrolyte for the aluminum electrolytic capacitor to solve the problem of low working voltage of a supercapacitor unit. The results showed that the hybrid capacitor had a high energy density and the ability of quick charging and discharging according to the electrochemical performance test. The capacitance was 84.4 μF, and the volume and mass energy densities were greatly improved compared to those of the traditional aluminum electrolytic capacitor of 47 μF. The analysis of electrochemical impedance spectroscopy （EIS） showed that the hybrid capacitor had good impedance characteristics.
基金supported by the National Natural Science Foundation(No.11561005)the National Science Foundation of Guangxi(No.2016GXNSFAA380248)。
文摘In this paper,we present a QP-free algorithm without a penalty function or a filter for nonlinear semidefinite programming.At each iteration,two systems of linear equations with the same coefficient matrix are solved to determine search direction;the nonmonotone line search ensures that the objective function or constraint violation function is sufficiently reduced.There is no feasibility restoration phase in our algorithm,which is necessary for traditional filter methods.The proposed algorithm is globally convergent under some mild conditions.Preliminary numerical results indicate that the proposed algorithm is comparable.
