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Viscosity and density data are presented on solutions of (CH3)4NBr, (C2H5)4NBr, (C3H7)4NBr, and (C4H9)4NBr in the concentration range 0-4 m and over the temperature range 15-35°. Use is made of the Vand equation, In / 0 = 2.5 6/(1 -), developed for concentrated suspensions, by substitution of the transformation = c7e°, where / 0 is the relative viscosity, is the volume fraction of the dispersion, c is the molal salt concentration, and 7e°is the "effective flowing volume" of the electrolyte at infinite dilution. The values of 7e°o btained for the four salts are shown to correlate with the B coefficient of the Jones-Dole equation for dilute solutions of the salts by the substitution in the Einstein equation for viscosity of B = 2.57,°. Values of 7"the "effective flowing volume," as a function of concentration and temperature are also obtained from the recent equation of Breslau and Miller, 7, = [-2.5c + {2.5c* 12 -4(10.05c2)(l -VW} I/!]/2(10.05)c2, and shown to correlate well with the limiting value of 7e°obtained from the Mooney equation. The behavior pattern obtained of Ve as a function of temperature gives indications of the hydration behavior of concentrated solutions of the four salts.

had 96.5% dy composition, was labeled 76.4% at C-3 (2-C1) and 20.1% at C-7 (3-C1).15 The composition of this mixture did not change substantially during two passes through the preparative gas chromatography separation procedures.(15) The propensity of benzonorbornenyl radicals to rearrange has been noted previously.16(16) S.

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SynopsisOptical rotation and density studies have been performed as a function of time on solutions of a single-strand gelatin in salt-free solutions and in solutions containing sodium bromide, tetramethyl and tetrabutylammonium bromide. The reversion to the collagen fold is shown to be first order in all cases but undergoes a change in magnitude as a function of an aggregation process which occurs at a concentration of approximately 0.1% w/v. The structuring effects of the electrolytes on the solvent are shown to relate to the extent of helix regeneration by the protein, in the presence of the electrolyte. The extent of helix regeneration is also shown to relate to the thickness of the electric double layer surrounding the protein molecule.