The results of this investigation extend and confirm conclusions given in the literature deduced from sound velocity and auxiliary data concerning alcohols. Acoustic velocities at 500 kcps were measured in a large number of alcohols and in three series of alcoholic binary solutions with a precision ultrasonic interferometer within the temperature range of 0°–80°C. Viscosities were determined at 25°C and densities within the range 14°–37°C. At fixed temperature, increase in sound velocity with increase in number of carbon atoms in primary alcohols follows a simple exponential law. The square root of the viscosity varies inversely as the molecular sound velocity. Secondary alcohols have lower sound velocities than the corresponding primary isomers because of lower densities. The increment in van der Waals' b per CH2 group is about 20 cm3 per mol. This holds true for all the homologous series studied. Fluorinated alcohols have much lower sound velocities than the alcohols from which they were derived. Rao's constant (molecular sound velocity) drifts somewhat with temperature, which is to be expected for associated liquids. The three series of binary solutions studied were n-propanol and isopropanol, n-propanol and n-octadecanol, and aqueous solutions of a propane diol derivative. Apparent molal adiabatic compressibilities for the component taken to be the solute vary as the square root of the molality at fixed temperatures.

high dielectric constant of barium titanate renders it suitable for certain types of capacitors. Previous investigators have reported the effects of impurities and additives on the dielectric and piezoelectric properties of barium titanate single crystals and ceramics. Chief among these have been studies

The general integral for the determination of the average resultant polarization j5 in the direction of the applied polarizing electric field is evaluated under the assumption that the spontaneous polarization vector of each crystallite is limited to a highly symmetric set of directions. With the further assumption that a ferroelectric crystal has a structure which is a slight distortion of a nonpolar structure, expressions for j5 are given which may be applied to any set of allowed polarization directions which is likely to occur; each of the 22 nonpolar crystal classes yields one such expression. The special cases of interest for each of the 10 polar classes are evaluated. A general expression for j5 as a function of electric field strength is obtained and used to determine hysteresis curves for several commonly occurring special cases. The angular distribution of polarization vectors after complete polarization is also discussed for these special cases.

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