ISSN:
1572-9567
Keywords:
critical exponent
;
critical parameter
;
gravity effect
;
laser interferometry
;
sulfur hexafluoride
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract A laser interferometry has been applied, in the present study, for determination of the critical temperature and critical exponents of sulfur hexafluoride (SF6). By means of laser holographic technique by real-time method, a series of Fraunhofer diffraction patterns due to the density fluctuation of the sample fluid in the very vicinity of the critical point has been successively photographed and analyzed. A dual-thermostat system which was designed and constructed for the present purpose has made the sample temperature constant within 15 μK for several days. We have obtained 107 data for (ρ L−ρ v)/ρ c along the vapor-liquid coexistence curve in the reduced temperature range 10−6≦¦ΔT *¦≦7×10−5 and additional 34 data for the isothermal compressibility in the single phase region. By analyzing these measurements with the aid of the simple power law, the critical temperature and the critical exponents of SF6 have been determined as T c=318.708±0.001 K, β=0.350±0.004, and γ=1.24±0.02, respectively.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00503795
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