The results show that the improvement of the slant improved oil-well pump 's internal structure and the optimization of the materials are the main factors to improve pump efficiency.

研究结果表明改进型斜井泵的内部结构的改进和材质的优选是泵效提高的主要因素。

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ETA's internal structure remains a mystery, all the more so as frequent arrests by the Spanish and French police have forced it continually to reorganise its leadership.

ECONOMIST: Reasons for caution over ETA's ceasefire declaration

This information should give scientists fresh insight into the internal structure of Earth's satellite.

BBC: Nasa reveals new information about moon probes crash sites