We are facing explosions of falcon tubes with poop samples after taking them off liquid nitrogen. They have been stored for 2-3 months. They are not pure poop, but mixed with glycerol. What could we do to avoid these explosions?
Hi,
Normally at this temperature, microbial activity is inhibated. These explosion can be due to the air dilitation (température difference between nitrogen -273°C and ambient temperature 25°C).
You can check if the falcon are hermeticly closed. If they are, let the gaz circulate with the outside of the falcon (turning the cap slightly).
Sorry for my english.
I saw my explanations... it's not so clear. When you put your samples out of the liquid nitrogen, directly turn the clap slightly, to permit the air to escape to the outside of the falcon. It will avoid the explosion because of overpression in the falcon (due to the air dilatation or biogaz production under ambiant temperature).
If liquid nitrogen add into another liquid , then pressure immediately boost up and the greater the pressure. Eventually the pressure gets high enough that the bottle explodes.rubber ducks in a liquid nitrogen bomb unless you put rubber ducks on top.Clearly there is some energy are there .This means that there had to be an increase in gravitational potential energy of water-Earth system. If this explosion was caused by a stick of dynamite, it would be clear. The dynamite would decrease in stored chemical potential energy and the water would probably increase in thermal energy, kinetic energy and gravitational potential energy. All would be clear. Energy would be conserved.
In order to make the transition from a liquid to a gas, it needs energy. The amount of energy depends on the amount of material that makes the transition as well as the type of material. This is constant multiplied by the mass is called the latent heat of vaporization. It can be expressed as:
Delta E (Thermal)=mL
Since this liquid nitrogen is much colder than the water, this increase in thermal energy for the nitrogen must itself come from the water. The water has to get colder. In a sense, that is where the energy to increase the height of the water comes from. It comes from a decrease in thermal energy of the water.
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