Oils segregate out of water because the oil-oil interaction is more favorable than the oil-water interaction.

油能与水分开，是因为油分子之间的作用比油水分子间的作用强。

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Oil and water do not blend.

油与水不相融。

《牛津词典》

Oil and water do not mix.

油和水不相融。

《牛津词典》

Natural micro-organisms in the water helped eat the oil and clean up the spill.

VOA: special.2011.04.23

A new underwater video - released as the latest hearings began - shows oil continuing to spill from the deep water well.

VOA: standard.2010.05.18

So far,the answer is no. Even though some of Louisiana's quarter-million hectares of rice farms are located within shouting distance of bespoiled marshes, rice ponds rely on fresh water from wells and rainfall - not saltwater that,even without oil, would kill tender plants.

VOA: standard.2010.06.17

Approximately 25.4 million gallons of an oil-water mix have been recovered.

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In addition to enabling vivid color labeling to be printed over nearly the entire disc, oil-based or water-based marker pens can be used to hand-write labels on these discs.

ENGADGET: Sharp intros first 100GB BDXL discs, Japan gets first dibs on July 30

Forty-nine vessels - oil skimmers, tugboats barges and special recovery boats that separate oil from water - were meanwhile working to round up oil, BP said.

BBC: Growing concerns over Gulf of Mexico oil leak