This Paper reports the synthesis of liquid rare earth stability R—9911 by using rare earth oxide etc.

以稀土氧化物和硫醇酸为主要原料，在一定条件下进行合成反应，再与其它助剂复配制得热稳定剂R—9911。

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R. russatum, R. cuneatum and R. fastigiatum are rare to be seen in other places in NW Yunnan, which could be considered as the conservation targets in the Lashihai region.

其中紫蓝杜鹃、 楔叶杜鹃和密枝杜鹃在滇西北其它地方少见，可列为保护目标。

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The history of aniseed and finally found out the identity of the mysterious, and the core of R plan is to ascertain the enemy plundered rare earth ore in china.

史大料终于查出神秘人身份，并弄清敌人R计划的核心是掠夺我国稀土矿。

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Scenes of smoking have become increasingly rare in non-R-rated movies, according to the MPAA. Of the movies portraying smoking in recent years, 72% were rated R, 21% were rated PG-13, and 6% were rated PG.

CNN: Should smoking trigger an R rating?