Kinematic viscosity, aqueous solutions

Brauer (B14), 1956 Extensive experimental study of film flow outside tube 4.3X130 cm. films of water, water + surfactant, aqueous diethylene glycol solutions, kinematic viscosity 0.9-12.7 cs. Nr = 20-1800. Data on film thicknesses, waves, maximum and minimum thicknesses, characteristic Reynolds numbers of flow, onset of rippling and turbulence, wall shear stress, etc. 

Rheology. PVP solubihty in water is limited only by the viscosity of the resulting solution. The heat of solution is — 16.61 kJ/mol (—3.97 kcal/mol) (79) aqueous solutions are slightly acidic (pH 4—5). Figure 2 illustrates the kinematic viscosity of PVP in aqueous solution. The kinematic viscosity of PVP K-30 in various organic solvents is given in Table 13. 

The side-by-side diffusion cell has also been calibrated for drug delivery mass transport studies using polymeric membranes [12], The mass transport coefficient, D/h, was evaluated with diffusion data for benzoic acid in aqueous solutions of polyethylene glycol 400 at 37°C. By varying the polyethylene glycol 400 content incrementally from 0 to 40%, the kinematic viscosity of the diffusion medium, saturation solubility for benzoic acid, and diffusivity of benzoic acid could be varied. The resulting mass transport coefficients, D/h, were correlated with the Sherwood number (Sh), Reynolds number (Re), and Schmidt number (Sc) according to the relationships... 

The kinematic viscosity considered in the simulations was that of water. Here, as diffusion constant D a value of 10 10 m2 s, a typical value for diffusion of small proteins in aqueous solutions, was taken. 

The kinematic viscosity of dilute aqueous solutions is ca. 0.01 cm s. So Nernst diffusion layers 5/v between 200 and 30 pm result at flow velocities between 5 and 100 cm s. For small molecules like benzene, tetrachloroethene, etc. the diffusion coefficients in water and in the PDMS membrane are of the same order. Then the time constant is approximately ... 

The K-value of KolUdon VA 64 is nominally 28, with a range of 25.2-30.8. The K-value of Plasdone S 630 is specified between 25.4 and 34.2. K-values are calculated from the kinematic viscosity of a 1% aqueous solution. Molecular weight can be calculated with the formula ... 

While the thickness of the hydrodynamic boundary layer can be estimated by L / Re", a similar estimate L / Pe" is obtained for the thickness of the diffusion boundary layer 8p, with n, and nj having values less than unity. Therefore, a rough estimate of the ratio 8p / is Pr " at n, = nj. The kinematic viscosity of mobile water-like liquids is of the order of V 10" cm%, the diffusion coefficients of molecules and ions in aqueous solutions are of the order of D 10 cm%, those of macromolecules D 10 cm%. Thus, in water and in similar... 

Table 7.62 Kinematic Viscosity of Aqueous levo-2,3-Butanedlol Solutions, Expressed Logarithmically, as a Function of Concentration and Temperature (32)...

Kinematic Viscosity of Aqueous Solutions of CARBOWAX Polyethylene Glycol 300... 

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