Soot is the product of the imperfectcombustion of fuel.
煤烟是燃料不完全燃烧的产物。
2
Soot is usually the product of the imperfectcombustion of fuel.
煤烟通常是燃料不完全燃烧的产物。
3
The experiments in laboratory and the combustion phenomena in actual boilers show that the most part in the said difference to be imperfectcombustion loss.