The exhaust velocity, though, is enormous—more than ten times that of a chemical rocket—and this makes ion propulsion extremely efficient.

但其排气速度却异常惊人，大约为化学燃料火箭的十倍—这使得离子推进器的效率非常高。

youdao

The coal gases came from two-stage gasification process and the exhaust gases containing combustible components from chemical and metallurgical industries are all low heating value (LHV) gas streams.

以两段法等制作的普通煤气及化工、 冶金企业中含可燃组分的废气等，都是低热值燃料。

youdao

Mainly used in thermal power, chemical industry, iron and steel and other enterprises of the heater, cold oil cooler, cooler, sampling cooler, exhaust gas cooler, heat exchanger, etc.

主要用于火力发电、化工、钢铁等企业的加热器，冷油器，冷水器，取样冷却器，抽气冷却器，换热器等。

youdao

Rather than eliminate nitrogen oxide via a bulky chemical treatment system that even the EPA questioned initially, EGR would make the motor do all the work by piping exhaust gas back into the cylinders and burning it again a cleaner, cheaper, lower-maintenance solution, which would set Navistar ahead of the pack.

FORBES: Death By Hubris? The Catastrophic Decision That Could Bankrupt A Great American Manufacturer