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In this paper, the Co 1−x Ni x Sb 3+y system ͑x = 0.1, 0.2; y = 0, 0.05͒ has been prepared by direct current induced hot press and annealing. Pores were made by annealing pressed Co 1−x Ni x Sb 3.05 pellets into Co 1−x Ni x Sb 3 pellets during annealing. It was found that from room temperature to 500°C, the pores with diameter larger than 1 m has significantly increased the Seebeck coefficient, considerably decreased the thermal conductivity, almost maintained the electrical conductivity constant, and therefore markedly improved the dimensionless figure of merit ͑ZT͒ of Co 1−x Ni x Sb 3 system. By comparing the samples, we conclude that inducing pores into skutterudites is an effective route to greatly improve the ZT.

Low cycle fatigue (LCF) and creep fatigue interaction (CFI) loadings are the main factors resulting in the failure of many critical components in the infrastructure of power plants and aeronautics. Accurate prediction of life spans under specified loading conditions is significant for the design and maintenance of components. In the present study, various LCF and CFI tests are conducted to investigate the effects of temperature, strain amplitude, hold time and hold direction on the fatigue life of P92 steel. To predict fatigue life under different experimental conditions, various conventional life prediction models are evaluated and discussed. Moreover, a new empirical life prediction model is proposed based on the conventional Manson-Coffin-Basquin (MCB) model. The newly proposed model is able to simultaneously consider the effects of temperature, strain amplitude, hold time and hold direction on predicted life. The main advantage is that only the known input experimental parameters are required to perform the prediction. In addition to the validation made through the experimental data of P92 steel conducted in the present paper, the model is also verified through numerous experimental data reported in the literature for various 9–12% Cr steels.

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A photocatalyst Sr(0.4)H(1.2)Nb(2)O(6)·H(2)O (HSN) nanopolyhedra with high surface area has been successfully prepared by a simple hydrothermal method. The as-prepared samples were characterized by XRD, BET, SEM, TEM and XPS. The electronic structure of HSN determined by DFT calculations and electrochemical measurement revealed that HSN is an indirect-bandgap and n-type semiconductor, respectively. HSN samples showed high photocatalytic activities for both pure water splitting and the decomposition of benzene. The rate of H(2) evolution over HSN was 15 times higher than that of P25 and the conversion ratio of benzene exceeded twice that of P25. The photocatalytic activities for water splitting can be greatly improved by loading various co-catalysts on HSN, such as Au, Pt, and Pd. The photocatalytic mechanisms were proposed based on the band structure and characterization results of the photocatalyst.

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