Faber-Theorie auf nicht-kompakten Riemannschen Flächen

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Berichtigung

Ohne Zusammenfassung     

Photoneutron cross sections for 9Be obtained with quasi-monoenerget1c photons

Absolute (γ, xn) cross sections for ⁹Be were measured with monochromatic photons from positron annihilation in flight in the energy range from 17 to 37 MeV. No pronounced structure was found in the cross sections in contrast to recent experiments performed with bremsstrahlung sources. The results are compared with many-particle shell model calculations.     

Funktionell substituierte zinnorganische verbindungen v. st]Phosphono- Und phosphonylmethyl-triorganostannane

The synthesis of phosphono- and phosphonylmethyl-triorganostannanes R₃SnCH₂P(O)(OR′)R′′ (R′′  OR′, C₆H₅) via an Arbuzov reaction of R₃SnCH₂I with P(OR′)₃ or C₆H₅P(OR′)₂ (R′′  CH₃, C₂H₅) is described. The new compounds have been studied with regard to their behaviour towards electrophilic (Br₂, HCl, HgBr₂) and nucleophilic (NaOH, LiAlH₄, LiR) agents. Their reaction with chlorophenylphosphines followed by reduction with LiAlH₄ yields the unsymmetrical methylenebis(phosphines) C₆H₅P(R)CH₂PH₂ (R  H, C₆H₅). The title compounds add to the carbonyl group of aldehydes and the CN bond of phenylisocyanate.     

Beitrag zum Studium des Spektrums der durch Reibung erregten Biegeschwingungen eines Stabes

Summary A beam with a built-in end is pressed with the free end upon a body moving with a constant velocityV. The spectrum of the beam oscillation produced by the friction force acting upon the free end is investigated theoretically and experimentally. The influence of the system parameters (velocityV and normal pressure) upon the shape of the spectrum is also determined.