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Hayes, C. E.; Carr, H. Y.

doi:10.1103/physrevlett.39.1558

Cited by 44 publications

(6 citation statements)

References 15 publications

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“…Closer to the critical point, we used the most recent data [18], obtained by an optical interferometric technique. In addition to a high precision, these data exhibit a good agreement with those of Hocken and Moldover [19] in the asymptotic regime (|t| < 5 × 10 −5 ) and are consistent with those from NMR experiments by Hayes and Carr [20].…”

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confidence: 87%

Crossover behavior in3Heand Xe near their liquid-vapor critical point

Luijten

Meyer

2000

Phys. Rev. E

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We present a detailed discussion of the crossover from mean-field to Ising critical behavior upon approach of the critical point, both for 3 He and Xe. By combining different sets of experimental data, we are able to cover an unusually large temperature range on either side of the critical temperature Tc. Below Tc, we thus can make an accurate comparison with a recent calculation for the crossover of the coexistence curve. For the regime above Tc, an analysis of the compressibility demonstrates that the crossover regime in 3 He is unexpectedly widened by a subtle interplay between quantum and critical fluctuations. 64.60.Fr, 05.70.Jk, 67.55.Cx Recently, there has been a renewed interest in the nature of the crossover from mean-field-like ("classical") to Isinglike critical behavior that occurs upon approach of the critical point. Although this phenomenon can be observed in a wide variety of experimental systems, including simple fluids, micellar solutions, and polymer mixtures, much of the recent attention has focused on its theoretical description. An important reason for this lack of experimental data is the width of the crossover region, which extends over several decades in the reduced temperature t ≡ (T − T c )/T c , where T c is the critical temperature. The crossover depends on the ratio between t and the (system-dependent) Ginzburg number G: Ising critical behavior occurs for t ≪ G and mean-field critical behavior is expected for t ≫ G. Throughout the crossover region, however, one has to stay within the critical regime, i.e., t 0.1. Hence, the full crossover can be observed only if G is sufficiently small. On the other hand, if G is extremely small, as for conventional superconductors which have G ≈ 10 −16 , the nonclassical region is so narrow that it becomes impossible to observe. Ideally, thus, one would need a system with a tunable Ginzburg number, as can actually be realized in polymer mixtures, where the Ginzburg number is inversely proportional to the molecular weight. Measurements of the crossover have indeed been reported for such systems [1,2], essentially confirming the existence of a crossover between the two universality classes. However, few studies have actually addressed the shape of the crossover curves. In Ref.[2] the concentration susceptibility χ as a function of t/G was shown to be well described by a phenomenological crossover function obtained by Belyakov and Kiselev (BK) [3], but it must be pointed out that χ increases by more than five orders of magnitude in the crossover region, making it difficult to judge even the qualitative agreement from a logarithmic plot. The effective susceptibility exponent, which is defined as the logarithmic derivative of χ,, is clearly a much more sensitive quantity. However, very few papers [5,6] have endeavored to discuss the shape of the crossover in experimental systems in terms of this parameter.It is the objective of this work to present an alternative description of experimental data exhibiting (part of) the crossover between mean-field-li...

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confidence: 87%

Crossover behavior in3Heand Xe near their liquid-vapor critical point

Luijten

Meyer

2000

Phys. Rev. E

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“…This is precisely what was observed optically by Cannell (1975) when he heated sulfur hexafluoride at the critical density and then rapidly cooled the system to T, +0.012K. More recently, Hayes and Carr (1977) used a quenching technique to study the coexistence curve of xenon near the critical point. They rapidly cooled samples in glass containers through the critical temp'erature.…”

Section: Attempts To Suppress Density Gradients Induced By the Easupporting

confidence: 73%

Gravity effects in fluids near the gas-liquid critical point

et al. 1979

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The presence of a gravitational field leads to both practical and fundamental limits of the resolution in critical phenomena experiments in fluids near the gas-liquid critical point. We present equations that yield estimates of the gravitational limitations in a variety of critical phenomena experiments for a large number of fluids and as a function of the magnitude of the gravitational field. Various strategies for improving the resolution of such experiments are discussed, including procedures that remove a fiuid from thermodynamic equilibrium (e.g., stirring). A comparison is made between the gravitational limitations in earth-bound experiments and those at the microgravitational levels that may become accessible in an orbiting laboratory. CONTENTS I. Introduc tion II. Critical Region Parameters for Fluids III. Gravity-Induced Profiles IV. Averaging Errors Due to Finite Sample Height A. Density Ineasurements B. Compre s s ibility measurements C. Specific heat measurements V. Limitations of Optical Experiments A. Beam bending B. Light-scattering experiments VI. Attempts to Suppress Density Gradients Induced by the Earth's Gravitational Field VII. Intrinsic Gravity Effects VIII. Discus sion Acknowledgments References 79 80 83 84 85 85 87 87 87 90 92 94 97 97 97 I~INTRODUCTION Near the gas-liquid critical point, gravity induces a density gradient in the fluid (Gouy, 1892; Teichner, 1904; Baehr, 1954). The resulting inhomogeneous distribution of the local properties of the fluid strongly affects. the interpretation of critical phenomena experiments in fluids (Weinberger and Schneider, 1952). A number of investigators have studied the consequences of gravitationally induced inhomogeneities for the in

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“…Indeed the very careful analysis of the vapour-liquid equilibrium by Leveh Sengers et al [17,18] have invariably yielded a value of /3 close to 0-35, while more recent results [19,20] obtained nearer to the critical temperature would even suggest that 3 takes exactly the 3D Ising value of 0.31. Our more probable value compares well with the rigorous 2D Ising fl---~.…”

Section: Discussionmentioning

confidence: 95%

“…It is true that the Ising model should be considered only as a crude model for our system: for the dense layer the adsorption is sitewise, but only one half of the sites are occupied and, in the low-density layer, adsorption is probably mobile. However the gas-liquid equilibrium, although it is obviously less well-represented by the Ising model than our 2D system, seems however to pertain to the same universality class [17][18][19][20]. Small deviations of our system from two-dimensionality cannot be absolutely ruled out.…”

Section: Downloaded By [Fu Berlin] At 07:39 27 November 2014mentioning

confidence: 97%

The critical exponent β associated with the two-dimensional condensation in the second adlayer of argon on the cleavage face of cadmium chloride

Larher¹

1979

Molecular Physics

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To cite this article: Yves Larher (1979) The critical exponent β associated with the two-dimensional condensation in the second adlayer of argon on the cleavage face of cadmium chloride, Molecular Adsorption isotherms of argon on the cleavage face of cadmium chloride have been measured in the vicinity of the critical point of two-dimensional condensation of the second adlayer. From these data we propose a value of 0-16 for the critical exponent fl, reflecting the two-dimensional character of the transition.

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NMR Measurement of the Liquid-Vapor Critical Exponentsβandβ1

Abstract: Using a new quenching technique to minimize gravitationally induced density gradients, we find that the shape {pL-pv)/pc ^^ ^^^ xenon liquid-vapor coexistence curve is described over the reduced-temperature range 3xl0''^ Show more

Cited by 44 publications

References 15 publications

Crossover behavior in3Heand Xe near their liquid-vapor critical point

Crossover behavior in3Heand Xe near their liquid-vapor critical point

Gravity effects in fluids near the gas-liquid critical point

The critical exponent β associated with the two-dimensional condensation in the second adlayer of argon on the cleavage face of cadmium chloride

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