Palladium-Carbon Composite Nanoparticle Films with Enhanced Electrocatalytic Activity for Hydrogen Peroxide Sensors

A nanocomposite electrocatalyst was prepared with the method of cluster beam deposition of palladium nanoparticle thin lms on carbon nanoparticle supporting layers and used as sensitive nonenzyme hydrogen peroxide sensors. An enhancement on the electrocatalytic activity of the palladium nanoparticles toward H2O2 reduction was observed, which was related to the coverage of the carbon nanoparticles. With one monolayer of carbon nanoparticles, the H2O2 detection sensitivity reached the maximum, which was more than twice of that of the pure Pd nanoparticles.

Strain transfer of surface-bonded fiber Bragg grating sensors for airship envelope structural health monitoring

This paper deals with an improved bonding approach of surface-bonded fiber Bragg grating (FBG) sensors for airship envelope structural health monitoring (SHM) under the strain transfer theory. A theoretical formula is derived from the proposed model to predict the strain transfer relationship between the airship envelope and fiber core. Then theoretical predictions are validated by numerical analysis using the finite element method (FEM). Finally, on the basis of the theoretical approach and numerical validation, parameters that influence the strain transfer rate from the airship envelope to fiber core and the ratio of effective sensing length are analyzed, and some meaningful conclusions are provided.

Optimization design of the stratospheric airship's power system based on the methodology of orthogonal experiment

The optimization design of the power system is essential for stratospheric airships with paradoxical requirements of high reliability and low weight. The methodology of orthogonal experiment is presented to deal with the problem of the optimization design of the airship's power system. Mathematical models of the solar array, regenerative fuel cell, and power management subsystem (PMS) are presented. The basic theory of the method of orthogonal experiment is discussed, and the selection of factors and levels of the experiment and the choice of the evaluation function are also revealed. The proposed methodology is validated in the optimization design of the power system of the ZhiYuan-2 stratospheric airship. Results show that the optimal configuration is easily obtained through this methodology. Furthermore, the optimal configuration and three sub-optimal configurations are in the Pareto frontier of the design space. Sensitivity analyses for the weight and reliability of the airship's power system are presented.

Stability and Passivity Analysis for Lur'e Singular Systems with Markovian Switching

This paper is concerned with the stochastic stability and passivity analysis for a class of Lur’e singular systems with time-varying delay and Markovian switching. By using the free-weighting matrices approach, a delay-dependent stability criterion, which guarantees that the system is stochastically stable and robustly passive, is derived in terms of linear matrix inequality （LMI）. Two numerical examples are provided to illustrate the effectiveness of the proposed method. 更多还原