Alloys of Mg-Zn-La system in Mg rich corner at 350℃ have been prepared in this study. Scanning electron microscopy （SEM）, electron probe microanalysis with energy dispersive X-ray spectroscopy （EPMA-EDS）, and X-r...Alloys of Mg-Zn-La system in Mg rich corner at 350℃ have been prepared in this study. Scanning electron microscopy （SEM）, electron probe microanalysis with energy dispersive X-ray spectroscopy （EPMA-EDS）, and X-ray diffraction （XRD） have been used to identify the phase equilibrium and the composition of each phase in the alloys. As a result, the isothermal section of Mg-Zn-La system in Mg rich corner at 350℃ has been determined. The result shows that, in addition to some binary phases, there exists a linear ternary compound called T-phase in Mg-Zn-La system at 350℃, in which the La content is about 8 at. pct ±0.4 at. pct and the Zn content is 8 at. pct- 48 at. pct. The T-phase has a C-centered orthorhombic crystal structure, and the lattice parameters are a=0.965-1.020 nm, b=1.121 1.142 nm, c=0.950-0.977 nm.展开更多
Alloys with different compositions in Mg-rich corner of Mg-Zn-La system at 400 ℃ were prepared,the phase equilibrium in the Mg-rich corner of Mg-Zn-La system was determined by scanning electron microscopy(SEM),electr...Alloys with different compositions in Mg-rich corner of Mg-Zn-La system at 400 ℃ were prepared,the phase equilibrium in the Mg-rich corner of Mg-Zn-La system was determined by scanning electron microscopy(SEM),electron probe microanalysis based on energy dispersive X-ray spectroscopy(EPMA-EDS) and X-ray diffraction(XRD),and the isothermal section at 400 ℃ was established. The results show that there exists a ternary compound(T-phase) with a constant La content and changable Mg/Zn contents in the Mg-Zn-La system. The mole fraction of La in T-phase is about 8%,and that of Zn is from 16% to 43%. There exist a two-phase equilibrium which consists of T-phase plus hcp-Mg and a three-phase equilibrium which is composed of T-phase,hcp-Mg and a liquid phase(L-phase) at 400 ℃ . The L-phase consists of 70% Mg,30% Zn and is free of La.展开更多
This paper proposed a method of injection-production system adjustment to solve the problem that the water flooding effect was restricted because of the horizontal and vertical contradictions during the development pr...This paper proposed a method of injection-production system adjustment to solve the problem that the water flooding effect was restricted because of the horizontal and vertical contradictions during the development process of fault block reservoirs. Considering the heterogeneity of reservoir, the Buckley-Leverett water flooding theory was applied to establish the relationship between the recovery and cumulative water injection. In order to achieve the goal of vertically balanced recovery of each section, the calculation method of vertical sectional injection allocation was proposed. The planar triangular seepage unit was assumed and sweep coefficients of different oil-water distribution patterns were characterized using multi-flow tube method. In order to balance and maximize the plane sweep coefficient, the calculation method of plane production system optimization was obtained. Then the injection-production system stereoscopic adjustment method based on equilibrium displacement was proposed with vertical sectional injection allocation and plane production system optimization. This method was applied to injection and production adjustment of BZ oilfield in southern Bohai. The effect of water control and oil increase was obvious. This method can greatly improve the effect of water flooding of offshore fault block reservoirs with the adjustment of injection-production system.展开更多
基金National Natural Science Foundation of China(No.50471025)Natural Science Foundation of Liaoning Province (No.20052028).
文摘Alloys of Mg-Zn-La system in Mg rich corner at 350℃ have been prepared in this study. Scanning electron microscopy （SEM）, electron probe microanalysis with energy dispersive X-ray spectroscopy （EPMA-EDS）, and X-ray diffraction （XRD） have been used to identify the phase equilibrium and the composition of each phase in the alloys. As a result, the isothermal section of Mg-Zn-La system in Mg rich corner at 350℃ has been determined. The result shows that, in addition to some binary phases, there exists a linear ternary compound called T-phase in Mg-Zn-La system at 350℃, in which the La content is about 8 at. pct ±0.4 at. pct and the Zn content is 8 at. pct- 48 at. pct. The T-phase has a C-centered orthorhombic crystal structure, and the lattice parameters are a=0.965-1.020 nm, b=1.121 1.142 nm, c=0.950-0.977 nm.
基金Project(50471025) supported by the National Natural Science Foundation of ChinaProject(20052028) supported by the Natural Science Foundation of Liaoning Province, China
文摘Alloys with different compositions in Mg-rich corner of Mg-Zn-La system at 400 ℃ were prepared,the phase equilibrium in the Mg-rich corner of Mg-Zn-La system was determined by scanning electron microscopy(SEM),electron probe microanalysis based on energy dispersive X-ray spectroscopy(EPMA-EDS) and X-ray diffraction(XRD),and the isothermal section at 400 ℃ was established. The results show that there exists a ternary compound(T-phase) with a constant La content and changable Mg/Zn contents in the Mg-Zn-La system. The mole fraction of La in T-phase is about 8%,and that of Zn is from 16% to 43%. There exist a two-phase equilibrium which consists of T-phase plus hcp-Mg and a three-phase equilibrium which is composed of T-phase,hcp-Mg and a liquid phase(L-phase) at 400 ℃ . The L-phase consists of 70% Mg,30% Zn and is free of La.
文摘This paper proposed a method of injection-production system adjustment to solve the problem that the water flooding effect was restricted because of the horizontal and vertical contradictions during the development process of fault block reservoirs. Considering the heterogeneity of reservoir, the Buckley-Leverett water flooding theory was applied to establish the relationship between the recovery and cumulative water injection. In order to achieve the goal of vertically balanced recovery of each section, the calculation method of vertical sectional injection allocation was proposed. The planar triangular seepage unit was assumed and sweep coefficients of different oil-water distribution patterns were characterized using multi-flow tube method. In order to balance and maximize the plane sweep coefficient, the calculation method of plane production system optimization was obtained. Then the injection-production system stereoscopic adjustment method based on equilibrium displacement was proposed with vertical sectional injection allocation and plane production system optimization. This method was applied to injection and production adjustment of BZ oilfield in southern Bohai. The effect of water control and oil increase was obvious. This method can greatly improve the effect of water flooding of offshore fault block reservoirs with the adjustment of injection-production system.
