Procuring liquid nitrogen locally will be a more challenging
task than obtaining a superconductor to experiment with. Check
your local yellow pages under "gas compressed industrial &
medical" suppliers. Call these suppliers and find one who is
willing to sell a small quantity (liter) of liquid nitrogen.
After finding a suitable company, the next problem is finding a
container to bring to the supplier to carry and hold the liquid
nitrogen. Most suppliers will not sell you liquid nitrogen if
you do not have a suitable container. For instances you would
not store liquid nitrogen in a closed vessel, because as the
nitrogen evaporates into a gas, dangerously high pressures can
build that could rupture or cause the container to explode.
Typically super cold fluids are transported in special
containers called Dewar flasks. Dewar flasks are so well
insulated they can hold a quantity of liquid nitrogen a few days
before it evaporates. In an open non-insulated container the
liquid nitrogen will only last a few hours be