The solid white substance burns with a pale flame, leaving nothing but water.

这种白色固体物质燃烧时发出苍白色的火焰，燃尽后只留下水。

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It is normal if there is any white substance released from the painted surface.

施工后表面如有少量白色物质释出，属于正常现象。

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Cholesterol has been perplexing researchers since 1769, when French Chemist Poulletier DE la Salle first purified the soapy-looking yellow-white substance.

从1769年开始，胆固醇就开始困扰研究者们，当时法国化学家Poulletier de la Salle第一次提炼出了这种具脂类的黄白物体。

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The charity said the birds were covered in "what appears to be the same white substance" that killed hundreds of birds in February.

BBC: 'Sticky substance' birds rescued in Devon and Cornwall

Many of the dead bats were discovered with a white substance on their nose, which was cultured and found to be an unidentified fungus.

NEWYORKER: The Sixth Extinction?

This summer she plans to hit a few more caves in Kentucky, including one where unclassified microorganisms are eating away at the ceiling, turning it into a squishy white substance like icing on a cake.

FORBES: Magazine Article