The soot produced by burning fossil fuels has a stronger warming effect because it contains a higher ratio of black carbon to sulfate, which reflects sunlight to produce a cooling effect.

燃烧化石燃料产生的煤烟增温效应较强，因为其中黑碳对硫酸盐的比例较高，而硫酸盐是可以反射阳光产生降温效果。

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A value related to the hiding power of a coating. The ratio of reflectance of the coating over black and white backgrounds at equal film thickness.

同涂层遮盖力相关的一个数值，以相同的涂层的厚度在黑色和白色背景下涂层反射系数的比值。

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According to the most recent Washington Post poll, black voters continue to oppose same-sex marriage by a ratio of 55-45, viewing the subject as a religious issue rather than a matter of civil rights.

FORBES: Obama Support Of Gay Marriage An Act Of Political Courage Or Just Catching Up?

Hillary Clinton, by a ratio of 2 to 1, Obama seemed mindful that he had won 80 percent of the black vote and less than 25 percent of the white vote.

NPR: Big Win for Obama in S.C., GOP Focuses on Florida