The original white lead pigments have oxidized and turned black.

原来白色的铅颜料已经氧化发黑了。

《柯林斯英汉双解大词典》

Green tea contains between 30 and 40 per cent of water-extractable polyphenols, while black tea (green tea that has been oxidized by fermentation) contains between 3 and 10 per cent.

绿茶含有30%——40%的可以水萃取的茶多酚，而红茶(绿茶经过发酵后的产物)只含有3%——10%。

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Black liquor is a water slurry containing both organics, which are oxidized and inorganics, which are recovered as pellets.

黑色押题是水和煤浆的混合物，一种既含有氧化的有机物和无机物，成为颗粒进行回收。

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