The energy of periodic surface structures in ferromagnetism

The periodic domain structures on unfavourably oriented surface layers of ferromagnetic materials were studied both experimentally and theoretically. The connection between the surface structure and the crystallographic orientation of the crystals was confirmed. All the terms contributing to the total energy of the surface layer were calculated. A general solution of the potential problem is given for arbitrary periodic distribution of the charges.

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Vapour—liquid equilibrium in binary systems formed by acetonitrile, 2-butanone and 1,2-dichloroethane

Isothermal vapour—liquid equilibria have been determined for 2-butanone + acetonitrile at 333.67 K, and for 2-butanone + 1,2-dichloroethane and acetonitrile + 1,2-dichloroethane at 333.15 K using a dynamic method. The apparatus used in these studies for the precise measurement of complete vapour—liquid equilibrium data is described and the reliability and accuracy of the measured data are considered in terms of the activity coefficients and of the dependences of the molar excess Gibbs energies on composition. Experimental inaccuracies are estimated for statistical treatment of the data both in terms of correlations and in consistency tests.     

Some sufficient conditions for the existence of a 1-factor

The following theorem is proved: Let G be a graph of even order. Assume that there exists a connected spanning subgraph F of G such that for every set U of four vertices in G, if the subgraph of F induced by U is a star, then the subgraph of G induced by U is complete. Then G has a 1-factor. The above theorem is derived from another sufficient condition for the existence of a 1-factor, which is also proved in this paper (Lemma 1).     

Calculation of charge vibration in fission with Strutinsky shell correction

The Strutinsky shell correction method has been applied to the two spheroid model to study charge vibrations in fission. The investigation is carried out by calculating the potential energy surface with respect to three degrees of freedom: charge vibration from the uniform value and the deformations of the two fragments. The results suggest that the effect of shells at Z = 50 and N = 82 do not cause large deviations from the liquid drop model charge density around mass 132; their effect is much more pronounced in the fragment excitation energy. The results also suggest that the fragment excitation and kinetic energies for a given mass ratio are markedly charge density dependent. Some features inherent to this treatment with respect to characteristic periods of individual degrees of freedom have been discussed.     

Kinetic study of dissolution of poly(vinyl chloride) in cyclohexanone

The kinetics of dissolution of five fractions of commercial poly(vinyl chloride) in cyclohexanone was studied at temperatures from 20 to 70°C. Good agreement was observed between the experimental results and equations expressing the dependence of the induction periods and the rates of dissolution on temperature and molecular weight. It was found that the apparent activation energy for the swelling process lies in the range 9–14 kcal/mole and the apparent activation energy for the dissolution diffusion process in the range 8–12 kcal/mole. The apparent dependence of activation energies on number-average molecular weight indicates that the chain ends are more important in determining the dissolution rate than the centers of the polymer chains.     

Verdampfungsw?rmen der Essigs?ure- und Propions?urealkyIester

Ohne Zusammenfassung     

Die Struktur der oberflächlichen Abschlussdomänen in den Ebenen (100) in Eisen

Zusammenfassung Auf Grund der Berechnung der Austauschenergie, der magnetostatischen und magnetoelastischen Energie und der Energie der Blochwände wird das bäumchenförmige Aussehen der oberflächlichen Abschlussbezirken an wenig gegenüber der Ebene (100)geneigten Ebenen erläutert. Aus dem Minimum der Gesamtenergie gehen dann, auch die Abmessungen dieser Bezirke in Abhängigkeit vom Neigungswinkel hervor.