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A filament of isotactic polypropylene, 15 μm diameter, is used to prove the theoretical predictions for a one-dimensional (1-D) process of solidification from nuclei at random to a linear polycrystal. The theoretical predictions were made in 1983. The agreement between theory and experiment is very good.

A 2D spherulite grows in a linear-temperature field from a nucleus of polypropylene at (0,0). The growth lines and the growth fronts are computed by the calculus of variations. The agreement between theory and experiment is satisfactory

Each spherulite growing undisturbed by other spherulites around a spherical inclusion possesses directly a channel. The channel damages some properties of the polymer, e.g. the bond strength, corrosion rate and breakdown voltage

Die Metalldispersitat von 0,5% PdAl2O3-, 0,5% PtAl2O3- und 1,5% PtAl2O3-Katalysatoren wurde mit Hilfe de Rontgenkleinwinkelstreuung untersucht. Unter Verwendung einer nach dem Kratky-Prinzip arbeitenden Kamera wurden die Differenzstreukurven Katalysator-Tonerdetrager ermittelt und aus diesen unter Voraussetzung globularer Metallpartikeln und Abwesenheit interpartikularer Streuung mit Hilfe der Guinierschen Naherung die Guinier-Radien RG errechnet. Wahrend bei der Pd-Katalysatorprobe stets positive Differenz-streukurven gemessen wurden, nahmen diese bei den Pt-Katalysatoren ab Streuwinkeln >0,022 rad negative Werte an. Deshalb konnte nur fur die 0,5% PdAl2O3-Probe die Porodsche Invariante und der Porod-Radius RP bestimmt werden. Aus RG und RP wurden die Parameter fur eine zwei- und eine einparametrige Verteilung abgeleitet. Ein Vergleich der erhaltenen Ergebnisse mit Werten aus Rontgenweitwinkelmessungen ergab befriedigende Ubereinstimmung. On the Dispersion of Metals in Supported Catalysts. II. Small Angle X-ray Investigation. on Platinum/Alumina and Palladium/Alumina Catalysts The metal dispersion in 0.5% Pd/A12O3. 0.5°% Pt/Al2O3 abd 1.5% Pt/Al2O3 catalysts was investigated by small angle X-ray scattering, Using a Kratky camera the difference scattering curves catalyst-carrier were evaluated. The assumption was made that the scattering centres are globular and that there is no interparticular scattering. From the Guinier approximation the Guinier radii RG of the metal particles were determined. With the Pd catalyst always positive difference scattering curves were found, whereas negative values were found with the Pt catalysts at a scattering angle greater than 0.022 rad. Therefore only for the sample with 0.5% Pd the Porod invariant and the Porod radius RP could be determined. From RG and RP the parameters of a two- and of a one-parametric distribution were calculated. The results are in good agreement with data from wide angle X-ray diffraction measurements.