Tom Thumb went up the kitchen chimney and looked out at the top—there was no soot.

汤姆大拇上了厨房的烟囱，从顶上看——没有煤烟。

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But pyrolytic stoves produce almost no soot-the carbon is all locked into the biochar.

但是热分解炉几乎不产生黑烟，碳全都锁在了生物炭中。

youdao

In addition to the significant merit of no soot emission, DME would be of better ignition quality, lower autoignition temperature and better atomization compared to diesel fuel.

除了无碳烟排放的重要特点以外，和柴油相比二甲醚还具有较好的燃烧性能、较低的自燃温度和较好的雾化特性。

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His face was not swollen and there was no soot in his mouth, the court heard.

BBC: Yaseen Ali Ege death: Father Yousuf Ege 'unusually calm'

When the fire went out, there were no brown stains, only smudges of soot.

NEWYORKER: Trial by Fire