OSMOTIC PRESSURE OF He$sup 3$ IN LIQUID He$sup 4$, WITH PROPOSALS FOR A REFRIGERATOR TO WORK BELOW 1 K

Journal Article · Sat Dec 01 04:00:00 EST 1962 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.128.1992· OSTI ID:4775592

London, H; Clarke, G R; Mendoza, E

An experimental study has been carried out of the osmotic pressure of solutions of the isotope He/sup 3/ in liquid He/sup 4/ at low temperatures, between 0.8 and 1.2 deg K. A superleak, a tube packed with a fine powder, acted as a semipermeable membrane which allowed only the superfluid He/sup 4/ to pass. The conclusion from these experiments was that the measured osmotic pressures were in reasonable agreement with values expected from the thermodynamic relations with other equilibrium properties of the mixtures, notably their vapor pressures. Thermodynamic equilibrium therefore seemed to have been attained under the conditions of the experiments. The second half of this paper concerns a study of the cooling which must take place during the adiabatic dilution of He/ sup 3/ by He/sup 4/. If the dilution is carried out at low temperatures where the solutions separate into two phases, the absorption of heat is estimated to be usefully large. After dilution the solution can be distilled, condensed and recirculated so as to make a continuously acting refrigerator. It should be possible to operate at temperatures of 0.1 deg K or below. (auth)

• Research Organization: Atomic Energy Research Establishment, Harwell, Berks, Eng.
• NSA Number: NSA-17-003618
• OSTI ID: 4775592
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 128; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ABSORPTION
ADIABATIC PROCESSES
COOLING
CRYOGENICS
HELIUM 3
HELIUM 4
ISOTOPES
LEAKS
LIQUIDS
LOW TEMPERATURE
MEASURED VALUES
MEMBRANES
OSMOSIS
PHYSICS
POWDERS
PRESSURE
SOLUTIONS
STABILITY
SUPERFLUIDITY
THERMODYNAMICS
TUBES
VAPORS
VISCOSITY