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Search Publications by: Robert F. Berg (Assoc)

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Displaying 51 - 60 of 60

Flow of microemulsions through microscopic pores

November 15, 1992
Author(s)
Dean C. Ripple, Robert F. Berg
The flow of the microemulsion dioctylsulfosuccinate (AOT)/decane/water through 0.1 and 1.0 um diameter pores was studied for water droplet volume fractions ranging from 0 to 0.5. The viscosity of these microemulsions, as measured in a capillary viscometer

Milliwatt mixer for small fluid samples

February 1, 1991
Author(s)
Robert F. Berg, Nicholas P. De Luca
Mixing without excessive heating is sometimes needed for temperature-sensitive fluids. We modified an inexpensive low-frequency electronic filter based on a mechanical resonator to produce a compact (16 mm) and low-power (l-3 mW) mixer for low viscosity

Milliwatt mixer for small fluid samples

February 1, 1991
Author(s)
Robert F. Berg
Mixing without excessive heating is sometimes needed for temperature-sensitive fluids. We modified an inexpensive low-frequency electronic filter based on a mechanical resonator to produce a compact (16 mm) and low-power (l-3 mW) mixer for low viscosity

Critical exponent for viscosity

December 15, 1990
Author(s)
Robert F. Berg, Michael R. Moldover
We have measured the critical exponent y characterizing the divergence of the viscosity eta  |T – Tc|^-y for carbon dioxide and xenon. The values of y for both fluids fall within the range y = 0.041 ± 0.001 and are consistent with the range y = 0.042 ± 0

Critical exponent for the viscosity of carbon dioxide and xenon

August 1, 1990
Author(s)
Robert F. Berg, Michael R. Moldover
The viscosities eta of carbon dioxide and xenon have been measured near their critical points and the critical exponent y characterizing the asymptotic divergence, eta ~ |T- Tc|^-y, has been determined. Both fluids yielded exponents in the rangey = 0.041 ±

Critical exponent for the viscosity of four binary liquids

September 15, 1988
Author(s)
Robert F. Berg, Michael R. Moldover
We have measured the viscosity of four binary mixtures near their consolute points: (1) methanol + cyclohexane, (2) isobutyric acid + water, (3) nitroethane + 3-methylpentane, and (4) 2-butoxyethanol + water. The viscosity data are consistent with the

Quantitative characterization of the viscosity of a microemulsion

September 15, 1987
Author(s)
Robert F. Berg, Michael R. Moldover, John S. Huang
We have measured the viscosity of the three-component microemulsion water/decane/ AOT as a function of temperature and droplet volume fraction. At temperatures well below the phaseseparation temperature the viscosity is described by treating the droplets

Viscosity and density of two alkali metal mixtures

September 1, 1987
Author(s)
Robert F. Berg, Michael R. Moldover, Savely Rabinovich, Alexander Voronel
We have measured the density and viscosity of a K-Cs binary mixture and a Na-K-Cs ternary mixture from their crystallisation points (234 K and 199 K respectively) to 300 K. Extrapolations of the fluidity data indicate that the effective glass temperatures

Viscometer for low frequency, low shear rate measurements

August 1, 1986
Author(s)
Robert F. Berg, Michael R. Moldover
We describe a torsion-oscillator viscometer whose low frequency ( 0.5 Hz) and very low shear rate (0.05 s-1) are required for measurements of shear sensitive fluids such as microemulsions, polymer melts and solutions gels, and liquid mixtures near critical

Viscosity measurements near a critical point using a novel torsion oscillator

May 1, 1986
Author(s)
Robert F. Berg, Michael R. Moldover
A torsion-oscillator viscometer has been constructed for the measurement of the viscosity of fluids near both liquid-vapor and liquid-liquid critical points. This viscometer has a resolution of ±0.2% and operates at a low frequency (0.6 Hz) and a very low