Continuous Flow Apparatus for Preparing Isotopically Pure He
نویسندگان
چکیده
A He isotopic purification cryostat has been developed, capable of sustained operation in continuous flow. Starting from a feedstock of helium of the natural isotopic ratio, He/He = x3 ≈ 10−7, it yields a purified product for which x3 < 5× 10−13 at a production rate of 3.3 STP m h−1. The isotopically purified He is being used for a variety of applications, including quantum evaporation experiments, studies of ion motion at the He II/vacuum interface, down-scattering and containment of ultra-cold neutrons, and investigations of the breakdown of superfluidity in He.
منابع مشابه
An Apparatus for Preparing Isotopically Pure He
The helium extracted from gas wells consists predominantly of He but it also contains traces (a few parts in 10) of the other stable isotope, He. For many purposes, the presence of the He may be neglected. Commercial He, widely used for a variety of cryogenic and other technological applications, usually consists of the two isotopes in their natural relative abundances. There are certain other ...
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