Liquid nitrogen usage in industry, biology and medicine

Industrial use:
In industrial production, through the liquid compressed air fractionation method to obtain the liquid nitrogen, can be used as a depth refrigerant, due to its chemical inertness, can directly contact with biological tissue, frozen immediately and won’t destroy biological activity.

1. Quickly freeze and transport food, or make ice products.
2. Study on low temperature physics.
3. Demonstrate low temperature state in science education.Soft objects soak in liquid nitrogen in normal temperature, which can be as brittle as glass.
4. Provide the temperature of superconductivity of high temperature superconductor.
5. Refrigerant can be used to quickly freeze biological tissue to prevent the tissue from being destroyed.
6. Used for industrial nitrogen fertilizer manufacturing.
7. Used for chemical testing, such as BET ratio surface area test method.

Biological and medical uses:

1. Eliminate red imported fire ants.
2. In surgery, quick freezing can be used to help stop the bleeding and remove the superficial layers of the skin.
3. Storage of living tissue, biological samples and sperm eggs.

(source:http://www.airseparation-plant.cn/liquid-nitrogen-usage-in-industry-biology-and-medicine/)