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Mathematical Representation of Viscosity of Ionic Liquid + Molecular Solvent Mixtures at Various Temperatures Using the Jouyban-Acree Model

Description: Article on mathematical representation of viscosity of ionic liquid and molecular solvent mixtures at various temperatures using the Jouyban-Acree model.
Date: May 6, 2013
Creator: Jouyban, Abolghasem; Soleymani, Jafar; Jafari, Farshad; Khoubnasabjafari, Mehry & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Motion of fluids with very little viscosity

Description: Report presenting a discussion of the laws of motion of a fluid with very low viscosity. Mathematical formulas that have been created in order to compensate for this lack of viscosity and the circumstances under which viscosity can be disregarded are provided.
Date: March 1928
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department

Tasks of air flow research

Description: The researches at the Gottingen Institute are discussed especially in regards to the physical properties of fluids. The three main properties of fluids examined concern density, viscosity, and compressibility.
Date: June 1926
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department

Recent results of turbulence research

Description: The first sections of this report deal with two prominent questions, namely the origin of turbulence and the characteristics of turbulent currents. In the third section conclusions are drawn for the flow along a rough wall, whereby an important relation for the velocity distribution is revealed. The principles are also applied to straight rough and smooth tubes.
Date: August 1933
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department

Note on the calculation of boundary layers

Description: The properties of the solutions of the hydrodynamic equations of viscous fluid by "boundary-layer omission" are discussed. A method is indicated for the numerical determination of the solution for a known initial profile u(x(sub o),y) and pressure distribution p(x) within the region.
Date: November 1940
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department

Selected Values of the Physical Properties of Various Materials

Description: Report issued by the Argonne National Laboratory discussing selected physical properties of various solids, liquids, and gases of interest in nuclear reactor heat transfer and fluid flow analysis. In most cases, values for thermal conductivity specific heat, density, viscosity, and Prandtl numbers are given as functions of temperature. This report includes tables, and illustrations.
Date: September 1958
Creator: Tebo, F. J.
Partner: UNT Libraries Government Documents Department

NBS Viscometer Calibrating Liquids and Capillary Tube Viscometers

Description: Report discussing measurements of viscosity made with relative viscometers. These instruments must be calibrated with liquids whose viscosities are known. NBS provides a series of 10 oils for this purpose. Their viscosities range from 0.02 to 450 poises and their temperature coefficients of viscosity range from 2.1 to 9.4 percent per degree C. The less viscous oils are more stable. Correction formulas for errors or conditions are presented.
Date: December 26, 1962
Creator: Hardy, R. C.
Partner: UNT Libraries Government Documents Department

The Effects of Color Concentrate in Polyolefins.

Description: Throughout history consumer products were generally manufactured from wood and metal. They either had to hold their natural color or become subject to painting. When plastics entered the industry, it was recognized for its ease of shaping, re-usability, physical properties and its low cost. One of plastics' greatest benefits is its ability to hold a given color from within allowing it to avoid use of paint. This paper will give a brief overview on the effects of pigments when incorporated in a polyolefin. It will provide a classification of the main types of pigments and how each effect the properties of the product through: crystallization, weatherability, opacity, coloristic values and of course viscosity.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: December 2001
Creator: Flora, Paul
Partner: UNT Libraries

Temperature dependent rheology of surfactant-hydroxypropyl cellulose solutions.

Description: The rheology of 1-8% hydroxypropyl cellulose (HPC) solutions has been studied in the temperature range of 20-45 degrees Celsius. The results showed that the relative viscosity at each HPC concentration decreases with increasing temperature. The relative viscosity decreases drastically at about 43 degrees Celsius due to a phase transition. The influence of anionic surfactant, sodium dodecylsulfate (SDS), induced gelation of a 2% HPC solution. The HPC solutions gelled at surfactant SDS concentrations ranging from 0.4 to 1.0 critical micelle concentration (CMC). The gelation of the HPC/SDS hydrogel is explained in the surfactant SDD - bridged HPC linear polymer chains. The complex viscosity - concentration profile was determined below the CMC of the SDS - water pair. The peak itself was a function of frequency indicating the presence of two relaxation times within the gelled network.
Date: December 2002
Creator: Snively, C. Todd
Partner: UNT Libraries