Liquid nitrogen is liquid state of nitrogen. Liquid nitrogen is widely used because it is inert, colorless, odorless, non corrosive and other characteristics. First, it can quickly freeze for transport food; second, it can provide the temperature required by high-temperature superconductor to display superconductivity; third, it can make refrigerants, which can be used to quickly freeze biological tissues to prevent tissue damage; fourth, it can be used for industrial nitrogen fertilizer, which can be used for chemical detection. The air separation plant liquid nitrogen is obtained by the physical characteristics of nitrogen. In industrial production and manufacturing, air separation plant liquid nitrogen is widely used.
