PAO and esters are the most useful base-stocks in synthetic lubricating oils.

PAO和酯类油是应用最广泛的合成基础油料。

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X is not used over the range of temperatures at which mineral lubricating oils are satisfactory, but rather above or below these temperature limits.

在X并不使用温度范围内润滑油脂在哪种矿物是令人满意的，而是高于或低于这些的温度范围。

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Most petroleum products, including kerosenes, fuel oils, lubricating oils, and waxes, are fractions of petroleum that have been treated to remove undesirable components.

其他石油产品，如汽油、芳烃溶剂、甚至包括有些沥青，则是通过完全或者部分合成而制造的。

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The main substance believed to have responsible for the deaths is PIB, which is used as a lubricating additive in oils to improve performance.

BBC: Calls to stop PIB discharges at sea after bird deaths