A gas-thermostated hydrogen-helium portable 100 l dewar flask

A dewar of 100 l capacity for storing liquid hydrogen and helium which is insulated by evaporating gas has been constructed. Its distinctive features are simplicity in construction and light weight which enables it to be easily manually transported. Its main parameters are: empty flask weight 42.5 kg, hydrogen evaporation 0.8% daily, and helium evaporation 1.8% daily. The result of heat parameters values measured for the flask are given.