A picture of the early stage of graphitization of a carbon black has been obtained from an x-ray study of a Fine Thermal (FT) carbon black heated for two hours at 2300°C. Nearest neighbor pairs of layers take on the graphite relation independently, producing both ABA and ABC sequences. There are two nearest neighbor layer spacings 3.35 A and 3.44 A corresponding to pairs with the graphite relation and pairs with random orientation. The (001) peaks must be corrected for the distortion broadening resulting from the two spacings, to obtain the parallel layer group thickness Le. The probability for the ordering of nearest neighbor layers P l is defined as the "degree of graphitization." A logarithmic plot is used for a rapid determination of P l and the layer diameter L. from the modulated two dimensional (hk) reflections.

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It is shown that a Fourier series associated with the Warren-Averbach line-shape analysis can be fitted with only five parameters to a pair of peaks. These interrelate the Fourier coefficients and thereby provide a simplified series which has been applied to the study of a Mo film on a Si crystal. The parameters include the average particle size, the first neighbor rms strain, a term which gives the variation in rms strain with cell separation, and two instrumental broadening coefficients. Although considerable simplification is possible, equivalent information can be obtained as compared with the original analysis and the ’’hook effect’’ is eliminated in the fitted coefficients.

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X-ray measurements of the Debye characteristic temperatures eM and the coefficient of thermal expansion for the Pd-Ag-Au ternary-alloy system are presented. The integrated intensities of Bragg reflections and lattice parameters were measured in the temperatures range 80-298'K. For all the alloys, the predominant lattice disturbance was due to thermal vibrations. No Significant effect due to static displacements was found. Debye temperatures were found to range from a low of 184'K for gold to a high of 290'K for palladium, with silver intermediate at 226 'K. The mean coefficient of thermal expansion was found to range from 9.8 x 10-6 for palladium to 17.9 x 10-6 for silver. Griineisen's relationship between the meansquare atomic-vibration amplitude and the thermal expansion for cubic solids has been found to be valid for these alloys and the constant YZ2 was found to be 0.167. The results suggest that a general weakening of the cohesive forces might be taking place as the smaller palladium atoms are replaced by silver and/or gold in the solid solution.