In the presence of an open flame or hot surfaces, chlorinated flourocarbon refrigerants decomposes and form .

A．petroleum crystals

B．phosgene gas

C．water vapor

D．carbon monoxide

[单选题,A1型题] The purpose of the flame in flame atomic-absorption spectroscopy is to（）A . Purify the sampleB . Desolvate and atomize the analyte atoms in a sampleC . Excite the analyte atomsD . Ionize the analyte atoms

[单选题]Flame Detail指的是（）。A . 火焰的大小B . 火焰精细度C . 火焰的高度D . 火焰的样本数

[单选题]If the flame from combustion in the cylinder of a four-stroke engine past the piston into the space below, the accumulation of flammable mixture would be ignited, thus resulting in _____.A．the crankcase explosionB．lifting of the cylinder safety valve

[单选题]If the flame from combustion in the cylinder of a four-stroke engine past the piston into the space below, the accumulation of flammable mixture would be ignited, thus resulting in （）.A . the crankcase explosionB . lifting of the cylinder safety valv

[单选题]When there is a flame failure in an automatically fired auxiliary boiler, the （）.A . air supply is shut offB . fuel supply is shut offC . water supply is shut offD . safety valve lift

[单选题]It is reported that the _in syria is hotting upA． StrengthB． violenceC．powerD．ACTIVITY

[名词解释] 热点 hot spot

[单选题]Heat Is KillerExtremely hot weather is common in many parts of the world.Al

[单选题]Heat Is KillerExtremely hot weather is common in many parts of the world.Al

[单选题]Heat Is KillerExtremely hot weather is common in many parts of the world.Al