1, Liquid nitrogen tank is always in the upright state. Do not tilt, especially if the liquid is inside the tank.
2. When all the liquid nitrogen evaporates, remove the remaining residue from the bottom of the liquid nitrogen tank (cryostat, tweezers, etc.).
3, Rinse with water.
(1) Suck out the vacuum pump and put the tube at the bottom of the tank..
(2) Before use, prepare a semi-cell dilution of bleach from 0.4 to 0.8 g / L of active chlorine. Add diluted bleach for at least 1 hour but not more than 2 hours. After each spin, then aspirate all bleach, rinse with at least 1/2 pot of water and rinse twice with 1/4 pot of water.
(3) After the canned food is completely dried, add liquid nitrogen. Otherwise, the bottom of the tank will be permanently ice. [Reminder: You can use a pipe to blow air at the bottom to accelerate evaporation. ]
4, Once completely dry, add liquid nitrogen to the tank 1/3.
5, Check one week later. If the level has really changed then the vacuum jacket is intact and your liquid nitrogen tank can be used to store the cells.