Abstract: A porous catalyst layer containing mixed conducting oxide having substantially a perovskite structure and containing a first element selected from Co and Fe, and a second element selected from In, Sn and Y arranged in the B site in the perovskite structure is contiguous to a second surface (1a) of a selective oxygen-permeable dense continuous layer (1) containing mixed conducting oxide. A porous intermediate catalyst layer (3) containing mixed conducting oxide and at least one of Co, Fe, Mn and Pd is contiguous to a first layer (1b) of the dense continuous layer (1). A porous reactive catalyst layer (4) provided with a metal catalyst selected from at least one of Ni, Co, Ru, Rh, Pt, Pd, Ir and Re and a support is continguous to the porous intermediate catalyst layer (3) in a manner to sandwich between the dense continuous layer (1) and the porous reactive catalyst layer (4).

Abstract: A stable micelle solution composition for recovering crude oil, which can form a homogeneous micro emulsion against brines in a wide range of salt concentrations.In a micelle solution composition comprising a hydrocarbon, brine, and a surface active agent, the above stated stable micelle solution composition can be obtained by specifying the surface active agent to be a mixture of (a) an ethylene oxide and propylene oxide block polymer, (b) an alkylbenzenesulfonate, (c) a polyoxyethylene alkyl ether sulfate or polyoxyethylene alkylphenol ether sulfate, and (d) a polyoxyethylene nonionic surface active agent other than the agent specified in (a).