Portrait of Jacob Picard in military uniform Military; Portraits

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Portrait of Leopold Meyerhof in his World War I officer's uniform Military; World War I; Portraits

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Calculation of Sparking Potentials of SF6 and SF6-GAS Mixtures in Uniform and Non-Uniform Electric Fields

A simple formula is developed to predict the sparking potentials of SF6 and SF6-gas mixture in uniform and non-uniform fields. The formula has been shown to be valid over a very wide range from 1 to 1800 kPa·cm of pressure and electrode gap separation for mixtures containing 5 to 100% SF6. The calculated values are found to be in good agreement with the previously reported measurements in the literature. The formula should aid design engineers in estimating electrode-spacings and clearances in power apparatus and systems.

Portrait of Hilde Rosenbaum with her father Julius Rosenbaum in military uniform Portraits Family

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Portrait of Walter Reiss in uniform Portraits Men

Walter Reiss, 1908-1937

Portrait of Moritz Reiss in uniform taken by the Imperial photographer; Vienna Portraits Men

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Studio portrait of Dr. Moritz Kroner (center) with two unidentified men in military uniform.

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Portrait of Dr. William Levison in military uniform Portraits Men

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Martin Goldschmidt in Prussian military uniform Portraits Men

Born 1879?; Married September 2, 1903 in Leipzig to Paula Harmelin, father of Henry H. Goldschmidt Gould and Ruth Augusta Beatrice Goldschmidt

Studio portrait of five Heimann brothers in military uniform during World War I.

l-r: Albert Heimann, Leopold Heimann, Nathan Heimann, Hermann Heimann and Max Heimann; Sons of Julius and Mina Heimann

Optimum geometry for uniform deposits on a rotating substrate from a point source

The application of an algorithm shows that maximum uniformity of film thickness on a rotating substrate is achieved for a normalized source-to-substrate distance ratio, h/r =1.183.

Exact analysis of simply supported rhombic plates under uniform pressure

The simply supported rhombic plate under transverse load has received extensive attention from elasticians, applied mathematicians and engineers. All known solutions are based on approximate procedures. Now, an exact solution in a fast converging explicit series form is derived for this problem, by applying Stevenson's tentative approach with complex variables. Numerical values for the central deflexion and moments are obtained for various corner angles. The present solution provides a basis for assessing the accuracy of approximate methods for analysing problems of skew plates or domains.

Surface Discharge Studies with Uniform Field Electrodes at Low Pressures

An investigation of power frequency (50 Hz) surface partial discharges in dry air, using 21r/3 Rogowski profile electrodes in the low pressure range of 0.067 to 91.333 kPa, shows that for the discharges occurring symmetrically around the electrodes and just outside the uniform field region, the breakdown voltages are 20 to 30% lower than those accounted for by the usual Paschen values. Emphasis, therefore, has been given to modified values of breakdown voltages for any useful calculations. The effect of reduced pressure on inception voltage has been discussed and an attempt has been made to explain the difference between the observed and calculated values on the basis of a pressure-dependent secondary ionization coefficient. It is shown that increasing the insulation thickness in a critical pressure range (0.067 to 0.400 kPa) does not allow any significant increase in the discharge free working stress of the insulation system. At higher pressures (>0.400 kPa) the increase in inception voltage with thickness and pressure follows an equation which is expected to hold for other insulating materials as well.