Question

What is flowing on ccr liquid helium or helium gas?

Answer 1

Advanced Research Systems closed cycle cryocoolers, also known as dry cryostats, allow a system to be cooled down to liquid helium temperatures without the use of cryogens. A more accurate term would be 'liquid helium free,' since they do use helium gas, in a closed loop.

Answer 2

Answer:

Helium is one of the basic chemical elements. In its natural state, helium is a colorless gas known for its low density and low chemical reactivity. It is probably best known as a non-flammable substitute for hydrogen to provide the lift in blimps and balloons.