A simple apparatus for liquefying neon is described for use in experiments that require a stable thermal environment at 27 K. This apparatus makes use of a closedhyphen;cycle refrigerator attached to an insulated cold finger inserted into a conventional stainless steel Dewar to liquefy a quantity of neon gas stored previously in a tank. The system is inexpensive and easy to use. Furthermore, the neon is recovered for subsequent reuse upon completion of the experiment. Starting with a Dewar holding a small coil that had not been precooled, and using a refrigerator with rated cooling capacity of 15 W at 26 K, approximately 0.5lof liquid neon was condensed into the Dewar in sim;4 h. The apparatus has been used to measure the critical currents of highTcoxide tape coils both with and without the application of an external magnetic field.
展开▼
