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Durch Pyrolyse-Gas-Chromatographie wurde eine Methode zur routinemasigen Analyse von Tensiden entwickelt. Sie beruht auf dem saurekatalysierten Abbau nichtionogener und anionaktiver Tenside im Curie-Punkt-Pyrolysator bei 500°C und auf dem basenkatalysierten Abbau der kationaktiven Verbindungen bei 300°C mit anschliesender gas-chromatographischer Untersuchung der gebildeten Bruchstucke. Ziel der Untersuchungen ist nicht nur die qualitative Identifizierung des Tensidtyps, sondern auch eine quantitative Aussage uber den Aufbau derartiger Produkte. Investigation of Surfactants by Pyrolysis-Gas-Chromatography A method for the routine analysis of surfactants using pyrolysis-gas-chromatography has been developed. This method is based on acid catalyzed degradation of nonionic and anion-active surfactants in Curie point pyrolyzer at 500°C and on base catalyzed degradation of cation-active compounds at 300°C, both followed by gas chromatography of the fragments formed. Aim of the investigations is not only the qualitative identification of the type of surfactant but also a quantitative statement on the composition of such products.

The beta and gamma radiations of237Pa have been investigated employing semiconductor and scintillation spectrometers and coincidence techniques. Sources of237Pa were obtained after bombardments of238U with bremsstrahlung and 14-MeV neutrons and subsequent chemical separation. From the total of 18γ-rays following the decay of 8.7±0.2 min237Pa 17 transitions, representing 99.9% of theγ-ray intensity, could be placed in a level scheme of237U. AQ β- value of 2.25±0.1 MeV has been determined.

In a paper read before the Section on Ophthalmology of the New York Academy of Medicine, on Feb. 20, 1911, I 1 recommended circumcorneal transplantation of mucous membrane from the mouth as a curative measure in diseases of the eye. Since then, I have performed this operation in a large number of cases, not only for trachomatous pannus, but also for scrofulous pannus, for torpid and dystrophic processes of the cornea, the character of which is often obscure, and also for herpes. An excellent field for grafting is presented by burns of the conjunctiva and cornea. In analyzing the curative effect of a graft on a diseased cornea, it seems to me that the important point is the improved nutrition of the cornea, diseased mucous membrane of the eye being removed and replaced by healthy mucous membrane from the mouth. However, not only will the nutrition of the cornea