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Calcium aluminate phosphor co-doped Eu(2+), Dy(3+), Nd(3+) is prepared by the combustion method. We study systemically the influences of the quantity of mixed Dy(3+) ion, the quantity of flux H(3)BO(3), the differences in dispersing methods between magnetic stirring and ultrasonic dispersing and the combustion temperature on the long-persistence phosphor. The analytical results indicate that Dy(3+) ion improves the properties of the phosphors CaAl(2)O(4):Eu(2+), Nd(3+). The appropriate quantity of flux H(3)BO(3 )to( )reduce the forming temperature of the sample was determined. The monoclinic single phase of CaAl(2)O(4) formed at 500 degrees C and remained steady. The calcium aluminate co-doped Eu(2+), Dy(3+), Nd(3+) was synthesized by dispersal of the raw material using the ultrasonic method, and it had better optical properties.

A mathematical model is proposed for polymer solution flow in dead-end pores, which was studied using micro-seepage of polymer solutions as an example. The mathematical model, including a continuity equation, a momentum conservation equation, and an equation of state, was solved by the finite difference method. The stream function and velocity contours were determined. The micro sweep efficiency when flooding the formation was calculated based on the velocity contour. The influence of elasticity, flow velocity, and viscosity of the polymer solution on the micro sweep efficiency was evaluated. It is demonstrated that the viscosity and the injection rate have a lesser effect on micro sweep efficiency than the elasticity of the polymer solution.