The construction of this ball bearing is similar to mounting two single row angular ball bearings back to back(DB).

这个球轴承结构越来越相似 ， 两个单列角球轴承背对背（DB）的。

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However things may turn out, Mahmoud Ahmadinejad comes back to the global scene with a lame-duck presidency that may last anywhere from few months if the mounting opposition succeeds in demanding a new election, or else go to a full term if it fails.

CNN: Commentary: Middle East is changed forever