Die spektrophotometrische Bestimmung des Kobalts in Kupferlegierungen

Ohne Zusammenfassung     

Die schnelle Bestimmung von Phosphor in Ferromangan, Ferromolybd?n und Ferrovanadin

Ohne Zusammenfassung     

Numerical approximation of Fourier-transforms

Conclusion A method has been presented for the numerical evaluation of the integrals occuring in Fourier transformation which is based upon the approximation of the transform as a function of its variable co. The numerical information necessary for the construction of the approximation is gathered by the formation of alternating trapezoidal and rectangular sums without the use of trigonometric functions The case of a polynomial approximation has been elaborated in detail and numerical results have been presented.It is clear that using the same principle other types of approximating functions may be employed. In cases where the Fourier transform decreases faster than any power an exponential approximation may be effective. Further analysis and experimentation will serve to improve this seemingly powerful method.     

Fehleruntersuchungen für das gewöhnliche Runge-Kutta-Verfahren

Ohne Zusammenfassung     

Elementarlösungen bei Anfangswert-Randwert-Problemen hyperbolischer Differentialgleichungen

Ohne ZusammenfassungHerrn Professor Dr.Robert Sauer zu seinem 60. Geburtstag am 16. 9. 1958 verehrungsvoll gewidmet     

Investigations about triggering of coaxial multichannel pseudosparkswitches

A fundamental problem of pseudospark switches is erosion in the borehole area. One way to reduce erosion is to distribute the current to several discharge channels. Essential for multichannel operation is a reliable ignition of all these channels. The aim of this work was to find out the requirements for a trigger for multichannel pseudospark switches and to develop a suitable trigger device. The investigations were made with a three channel pseudospark switch. The developed trigger is a pulsed hollow cathode discharge with a 3 mA dc-preionization. A trigger voltage of 4 kV results in a current of about 6 A in the hollow cathode of the trigger-section. This hollow cathode discharge causes a trigger current into the hollow cathodes of the pseudospark chambers. The trigger current which is necessary to ignite an equally distributed discharge has to be at least 3 mA into each main switch hollow cathode. A jitter of 2 ns was achieved for the coaxial multichannel pseudospark switch