The intramembrane transport properties of carbohydrates were investigated in cellophane. The experiments performed were the measurement of net volume transfer under a concentration and pressure gradient and the solute transfer due to a concentration difference together with the physical properties of the membrane. The matrix of phenomenological coefficients characteristic to the transport was established after the phase boundary contributions were extricated from the experimental transport data. These thermodynamic coefficients were then interpreted through the Spiegler‐Kedem‐Katchalsky frictional model.The analysis of the frictional coefficients clearly indicated the importance of solute‐polymer interactions. The magnitude of solute‐solvent frictional coefficients in the membrane were compared with the corresponding interactions in free solutions. Their differences were explained in terms of the interaction of the solute with the macromolecular network and were quantitatively expressed by introducing two reduced frictional coefficients. The tortuosity factor was shown to be related to these interactions and not a simple geometric property of the membrane. The temperature dependence of the frictional coefficients was established.

A correlation has been developed for estimating the liquid viscosities of petroleum fractions at 100°F and at 210°F. When used with the ASTM viscosity chart (or its analytical equivalent), the new correlation provides a method for the prediction of viscosity‐temperature behavior of fractions from the Watson characterization factor and specific gravity. Essentially an extension of an API Data Book viscosity nomograph, the proposed correlation substantially improves on the accuracy and increases the range of applicability of this method. Greatest accuracy is achieved for petroleum fractions in the kerosene to heavy gas oil range, although acceptable accuracy for most engineering calculations is also obtained for lube oils and for many complex pure heavy hydrocarbons.

Dialysis of binary aqueous solutions of several sugars through a cellophane membrane was studied in a stirred botch diolyzer. Sharwood numbers describing mass transfer resistance in the fluid adjacent to the membrane were determined as a function of the corresponding Reynolds and Schmidt numbers. The results establish a reproducible environment for membrane testing in which a known controllable and small interfacial resistance is placed in series with that of the membrane. The results ore also shown to support, for this geometry, the postulation of a third power relationship between eddy diffusivity and dimensionless distance from the phase boundary as well as the Sherwood-Ryan nondirnensionolization of this distance.The increased use of membranes as mediators of interfacial mass transfer has provided yet another incentive for the study of turbulent mass transfer at solid-liquid interfaces. In order to determine mass transfer resistances within membranes, in the design of plant and pilot plantscale devices and in the conduct of laboratory experiments, knowledge of interfacial mass transfer coefficients is needed and the adequacy of present knowledge is tested, particularly when turbulent flow conditions are encountered or desired. The results reported here were obtained as part of a study of transport near and within cellophane membranes through which binary solutions of one of several sugars in water were being transferred. The principal mechanism of transport was dialysis: a relative movement of species in response to concentration differences. The inseparable presence of volume transport was recognized, however, and certain corrections were made for it. The results of the intramembrane transport studies are described in a separate paper (10).Membrane evaluation has for the most part been conducted by chemists and biological scientists and the literature expresses relatively little concern for the difference between overall resistance to transport between phases, and that resistance inherent to the membrane (4, 15, 16). Some prior studies have been reported in which the presence of interfacial resistances was recognized and steps were taken to measure and control them ( 3 , 1 1 ) . However, firm establishment of how interfacial resistances vary with diffusional and hydrodynamic parameters in a convenient and desirable environment for testing membranes has not yet been achieved. Since it is important to emphasize intramembrane transport, turbulence is often introduced to minimize interfacial resistances and to insure known concentrations at the membrane surfaces. When the turbulent interfacial resistances are known, in terms of diffusional and hydrodynamic parameters, accurate measurement of transport across a membrane under a given condition is reduced from many experiments to one.A convenient and commonly used controlled environment for measuring membrane resistances is shown in Figure 1: a pair of identical, enclosed, stirred, cylindrical chambers sharing a circular boundary across which the membrane is inter...

The coefficients of the Benedict-Webb-Rubin equation of state have been developed for argon. By employing these coefficients, the volumetric behavior of argon has been predicted with an average deviation of 0.241 % for five hundred ninety-seven smoothed and experimental data points in the superheated region.At temperatures below the critical, two sets of Go's, one for the liquid and one for the vapor, were needed to relate the vapor pressure to the densities of saturated argon. However, consistent fugacities for the saturated vapor and liquid argon could not be predicted with these Co values. Therefore, another set of C, ' s was developed by equating the pure component vapor and liquid fugacities along the vapor pressure curve. These values were used to test the applicability of the equation of state to predict derived thermodynamic properties.The original BWR expression for calculating isothermal pressure effects on enthalpy was modified to include explicitly the temperature dependence of the coefficient C,. Vapor-liquid equilibrium relations for the argon-nitrogen system predicted by the standard BWR procedure were compared with experimental data.The empirical equation of state of Benedict, Webb, and Rubin ( 3 ) was originally developed to correlate and predict the fugacities of light hydrocarbon mixtures. Since its publication, it has been used extensively to represent the volumetric and phase relations of light hydrocarbons and some nonhydrocarbons. Several papers (3 to 5, 8,13) have been published describing success in predicting high pressure phase behavior of multicomponent systems. AS the BWR technique gained widespread use, more and more shortcomings were reported (8, 1 3 ) . Most of the difficulties have been observed in predicting P-V-T relationship within the critical region, and predicting vaporliquid equilibrium ratios at low temperatures. As a result, it is widely believed that the BWR equation is inadequate for systems at low temperatures. Attempts have been made to modify the equation and the combining rules for mixtures in order to use it for low temperature predictions. The limitations of the BWR method and suggested modifications have been summarized by Canjar ( 8 ) , Ellington ( 1 3 ) , and Lin (20). The application of the BWR approach to the cryogenic systems nitrogen-methane (26) and nitrogen-carbon monoxide ( 2 4 ) at temperatures below 200"R. established that temperature is not a limiting condition for use of the technique. The results of the present work extend the application of the BWR method to another cryogenic material, namely, argon.As was recently stated by Thodos ( 2 5 ) , argon is a good substance to test the validity of an equation of state. Its molecule is monatomic and therefore its properties should resemble those expected from a simple fluid as defined by Pitzer ( 2 3 ) . Furthermore, its relatively high atomic weight provides a good test for any equation employing a high power series in density. Beattie and Bridgeman (2) showed that such an equation can apply to argon.Th...

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