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Observation of substituted cyclohexadienyl type radicals by muon spin rotation in substituted benzene at different concentrations of added p-benzoquinone or duroquinone allows a selective determination of rate constants for the reaction of the radicals with oxidants. Methyl substitution has no effect, methoxy substitution enhances the rate constants for the ortho and para substituted isomers.

The distribution of muon polarization between different radicals observed in neat p-di-fluorobenzene, aniline and bromobenzene and their binary mixtures with benzene has been measured and is interpreted in terms of relative rate constants for Mu addition. Mu shows the same intramolecular and intermolecular selectivity pattern as the heavier hydrogen isotopes, but its selectivity is smaller.

Abstract: Rate constants for the reaction of muonium with benzene in water, methanol and n-hexane and for the reaction of muonium with p-difluorobenzene, anilin, hexafluorobenzene and styrene are reported. All rate constants are below the calculated diffusion controlled limit. The activation energy for the reaction of muonium with benzene in n-hexane is very small, indicating the possibility of tunnelling by muonium.

Abstract: Hyperfine coupling constants for muonium substitited hydrazyl radicals are reported. They are compared with the existing data for the hydrogen analogs. The influence of the temperature and the solvent are given.

Consider a Toda chain with uniform friction. Starting with an initial condition that represents a soliton, we investigate its decay. The main result is that the solitary character is almost completely preserved.

Thirty-seven children were each fed an average of 30 g of FPC every day for 9 weeks, except for the 4- to 7-day period when most (all except eight) had measles. After the first 3 days, the diets were well accepted, well tolerated, and totally consumed. The performance of the group was similar to a milk-fed group. There was a decrease in hemoglobin concentrations in both groups, which may have been due to iron deficiency.

In this article it will be proved that the commonly used formula for dead time corrections :[xxx] (Ν' is the true and Ν the measured count rate, r the dead time) is correct for a G.M.-counter tube and also for high count-rates. However τ seem to be a function of N.

Die Luftspaltelektrode nach Ružicka wurde in einigen Punkten verbessert. Ihre Zuverlässigkeit wurde durch Anwendung einer Einstabmeßkette erhöht; ein neues System der Probezugabe bietet eine bessere Genauigkeit in der Praxis. Die Elektrode wurde zur Messung von Carbonatkonzentrationen im Betrieb von 5 · 10-2–5 · 10-4 M eingesetzt, wobei die Genauigkeit 2–9% betrug. Sie wird zur Umweltanalyse von Carbonat angewendet.

Abstracts of papers from Annual Meeting of the American Thoracic Society held in conjunction with the Meetings of the National Tuberculosis and Respiratory Disease Association and the National Respiratory Disease Conference, Los Angeles, California, May 16-19, 1971.

Molybdenum-fed rats housed in galvanized cages gained less weight and had lower hemoglobin levels than similarly fed rats housed in stainless steel cages. Since similar effects were produced in rats housed in stainless steel cages by increasing the zinc in their diets, it was concluded that zinc consumed by chewing on zinc-coated cages was responsible for the abnormalities noted.

WE have recently examined a number of bars of silver of East European origin for their radioactivity level. Out of a series of a hundred bars, we have radio-assayed seven bars picked at random. Engraved on the base of the bars are, among other engravings, the weight in grams (on the average 11,100 g); the number 999 (ref. 8), most probably indicating the purity; and the number 1971, presumably the year of manufacture.

Reactions of 11C recoil atoms with C6H6in the presence of O2lead to the formation of high yields of labeled Ph‐CHO in the gaseous (6%) and liquid (8‐10%) phase, whereas none is detected in the solid phase.