The nitrogen content in the air is the most, and nitrogen is mainly used for ammonia synthesis, and is also an important raw material for synthetic fibers, synthetic resins, and synthetic rubber. Nitrogen can be used as a preservative, refrigerant, and can also be used to make fertilizers.Followed b

1. The gas in the oxygen cylinder cannot be completely used up, and the residual pressure of not less than 0.05MP should be retained.2. The distance between the oxygen cylinder and the open flame should be no less than 10 meters, should not be close to the heat source, and should not be exposed to s