Richard E. Lindstrom

A new blood-flow pharmacokinetic model for ethanol

A multicompartmental mathematical model, taking into account observed vascular concentration gradients and blood flow rate limitations, has been proposed. Based on blood flows and blood and tissue volumes reported in the literature and in personal communications, an appropriate model was elaborated for ethanol in the dog. The relatively high values of r2and a correlation coefficient determined for the simultaneous computer fitting of mean observed blood ethanol concentration, time data from two administered doses, support the proposed model. While the surgery is prohibitive for human experimentation, correlations may be extended to man. The elaboration of a more complete multicompartmental model for ethanol should prove beneficial in revealing the relationships among the doses of alcohol, the circulating blood ethanol concentrations, and physiological and psychomotor test parameters.

Amide-water interactions in cosolvent systems. I. Solubilities and apparent molar volumes of methyl paraben

Solubility and apparent molar volume data are used to demonstrate effects of amide alkylation on amide-water interactions at 25° C. Precise measurements were made of the apparent molar volumes of the amides in binary amide-water mixtures using a dilatometric technique. The results show that the apparent molar volumes of alkyl-substituted amides in water pass through a minimum at an amide concentration which varies inversely with the degree of alkylation. Further studies showed that the solubilities of methyl paraben (methyl-p-hydroxybenzoate) and naphthalene in various amide-water solvent systems increased in characteristic fashion with amide alkylation.

The effect of urea on the solubility of methyl p‐hydroxybenzoate in aqueous sodium chloride solution

The effects of sodium chloride and urea, separately and together, on the solubility of methyl p‐hydroxybenzoate in water have been studied. Sodium chloride decreases and urea increases the solubility. Observed and calculated “salting‐out” parameters have been obtained for addition of sodium chloride to the benzoate‐urea‐water systems. Good agreement was observed between calculated and observed values, and the change in the “salting‐out” parameters as the concentration of urea altered may indicate dipole‐ion interaction between urea and sodium chloride.

The apparent molal volumes of 1:1 electrolytes in urea solution. II. Variation of apparent molal volume with salt concentration

AbstractThe apparent molal volumes of NaCl, NaBr, KCl, KBr, LiCl, and CsCl were measured as a function of salt concentration in 1m and 8m aqueous urea at 25°C. It was found that equations of the form

The apparent molal volumes of mixtures of 1:1 electrolytes in aqueous urea solutions: A test of Young's rule

\phi = \phi _0 + S\prime \surd \bar C + b\prime C

Extended Hildebrand Solubility Approach and the Log Linear Solubility Equation

where the limiting slopeS′ is the same for all the salts in a given concentration of urea, accurately describe the data for salt concentrations less than 1M. The values found forS′ were 1.52 in 1m urea and 1.00 in 8m urea. These are in good agreement with estimated values of the Debye-Hückel limiting slope.

Factors affecting water vapor transmission through free polymer films

The solubility of methyl p‐hydroxybenzoate was determined in a series of amide‐water cosolvents in the temperature range 25–40 °C. Thermodynamic values for the transfer of the ester between the cosolvent system were calculated using a method which permits a focus on the effects of amide alkylation. The results are interpreted in terms of hydrophobic bonding principles which suggest that the alkyl groups on the amide detract from amide‐water interaction and enhance amide‐ester interaction.

Factors affecting water vapor transmission through polymer films applied to solid surfaces

The apparent molal volumes of sodium chloride, sodium bromide, potassium chloride, and potassium bromide were determined for each salt at 2.000m in 8.000m urea-in-water solvent systems at 25°C. In each instance, the volumes were larger than those observed for the same salts in pure water. The volume changes on mixing the six pairs of these salts were measured at a constant ionic strength of 2m in the same urea-water solvent. The results of this test suggest that Youngs rule applies equally well in urea-water solvent systems as it does in pure water.