The results of an examination of "O" ring gaskets remove from the HRT following a discovery that the water in the leak detector system contained 1000 ppm chloride are presented.

The essential physical and mechanical properties of materials which enter into the design considerations of high-temperature systems have been outlined, and the relationship of these factors to the detailed design of structural members noted. Particular attention is given to the phenomenon of strain-cycling and relaxation, and several engineering devices wherein these effects can markedly influence design are mentioned. Techniques and apparatus for the measurement of strain-cycling and relaxation properties are described and some recent data for Inconel at 1500 F is reported. A brief discussion is presented on design-criterial for high-temperature applications, and it is pointed out that in some high performance devices the considerations of the strain-cycling phenomenon may impose the design philosophy of "steady-state" operation. Some elementary applications of strain cycling data to design are described, and test experience indicates that analytical techniques can be developed for predicting with reasonable reliability of the fatigue life of structures.

A spectrophotometric method for the determination of cerium with Tiron (disodium-1,2-dihydroxybenzene-3,5disulfonate) was applied to the determination of cerium in samples which contain uranium and zirconium. The cerium-Tiron complex in solutions of pH 8 or greater exhibits an absorption maximum of 500 mu . This reagent does not react with any other lanthanide element. The interference of iron, uranium, and zirconium was eliminated by extracting these interfering elements with a solution of trioctylphosphine oxide in cyclohexane. (auth)