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141.
La0.6Sr1.4MnO4 layered perovskite anode material for intermediate temperature solid oxide fuel cells
Chao Jin Zhibin YangHonghe Zheng Chenghao YangFanglin Chen 《Electrochemistry communications》2012,14(1):75-77
La0.6Sr1.4MnO4 (LSMO4) layered perovskite with K2NiF4 structure was prepared and evaluated as anode material for La0.8Sr0.2Ga0.83Mg0.17O3 − δ (LSGM) electrolyte supported intermediate temperature solid oxide fuel cells (IT-SOFCs). X-ray diffraction results show that LSMO4 is redox stability. Thermal expansion coefficient of LSMO4 is close to that of LSGM electrolyte. By adopting LSMO4 as anode and La0.6Sr0.4Co0.8Fe0.2O3 (LSCF) as cathode, maxium power densities of 146.6, 110.9 mW cm− 2 with H2 fuel at 850, 800 °C and 47.3 mW cm− 2 with CH4 fuel at 800 °C were obtained, respectively. Further, the cell demonstrated a reasonably stable performance under 180 mA cm− 2 for over 40 h with H2 fuel at 800 °C. 相似文献
142.
A series of solid solutions of Al2−δScδW3O12 (δ = 0-2) were successfully synthesized by the solid-state reaction with aluminum oxide, scandium oxide and tungsten trioxide as raw materials. The phase composition and structure of the products were analyzed by X-ray powder diffraction and scanning electron microscopy, while the linear thermal expansion coefficients were measured by thermo dilatometer. The results indicate that Al2−δScδW3O12 with high purity can be successfully prepared by the solid-state method. All samples of different δ values crystallize in the same orthorhombic structure with space group of Pnca. The lattice constants and cell volume increase linearly with increasing Sc content. The average linear thermal expansion coefficients of Al2−δScδW3O12 measured by thermo dilatometer indicate that the thermal expansion coefficients of the solid solutions could be adjusted to the desired values, such as positive, near zero or negative by simply changing the δ value. 相似文献
143.
Several new phases containing platinum in Y-Ba-Cu-O system are reported in this paper. When Ba-Y-Cu-O system containing platinum is sintered at 950°C, two hexagonal phases YBa2(Pt, Cu)3O9-δ and Ba4Pt1+x Cu2-x Cu2-x O9-δ (x = 0.1 – 0.9) are found, respectively. The super-K2NiF4 structure Ba x Y2-x (Cu, Pt)O4 is obtained above 1000°C in the Y-Ba-Cu-O system containing platinum. Electrical properties of these phases are also reported. 相似文献
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146.
The converse comparison theorem has received much attention in the theory of backward stochastic differential equations (BSDEs). However, no such theorem has been proved for anticipated BSDEs. In this paper, we derive a converse comparison theorem by first giving an existence and uniqueness theorem for adapted solutions of anticipated BSDEs with a stopping time and then related to (f,δ)-expectations induced by anticipated BSDEs. 相似文献
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148.
研究L-预拓扑空间中L-开集的一些近似形式(其中L是有逆合对应的C-格):θ-L-开集,δ-L-开集,α-L-开集以及β-L-开集。证明了(1)当L的最大元1是并既约元时L-预拓扑空间的连通性、θ-连通性、δ-连通性和α-连通性是等价的;(2)θLTop是LTopsθ、LTop以及LTopθ的反射满子范畴,δLTop是LTopsδ和LTopδ的反射满子范畴;(3)当格L为幂集格时αLTop是LTopsα和LTopα的余反射满子范畴;θLPTop是LPTopsθ、LPTop以及LPTopθ的反射满子范畴,δLPTop是LPTopsδ和LPTopδ的反射满子范畴。 相似文献
149.
Qingling Zhang 《Annals of Differential Equations》2012,(1):115-126
In this paper,the Riemann problem of the 1-D reduced model for the 2-D Euler equations is considered and the Riemann solutions are obtained.It is proved that,as the pressure vanishes,they converge to two kinds of Riemann solutions to the 1D reduced model for the 2-D transport equations:one contains δ-shocks,the other contains vacuum. 相似文献
150.
In this paper, for the highest weight module V4 of sl(2,C) with the highest weight 4, we describe subalgebras Sβ(V4)θ+ and Sγ(V4)θ+ of the βγ-system coset S(V4)θ+ by giving their generators. These coset subalgebras are interesting, new examples of strongly finitely generated vertex algebra. 相似文献