Isotopic analysis, viii

From the isotopic analysis of ethylene produced from the photolysis of CH4 + CD4 mixtures, they conclude (VIII-123) is a dominant process for the ethylene production. 

Using his positive ray analysis,. 1.. 1. Thomson hits shown that atmospheric neon contains two isntojtes, one with an atomic weight 20 and the other 22. This conclusion has Item confirmed by Aston, a who obtained evidence of two isotojs H of atomic weights 20 and 22 in proportion ) to 1. This accounts for the accepted value of 20.2, There is also some evidence of a third isotope of value 21, comprising about 1 kt cent of the whole. If this conclusion is confirmed this would furnish mi interesting triad somewhat similar to those found in (Jroup VIII. 

Mass spectra have been used principally for the determination of molecular weights and deduction of the detailed composition of the molecule from the isotopic patterns of the various ions. Structural information can also be obtained from a detailed analysis of the fragmentation pattern. The clusters which have been studied by mass spectrometric methods have largely been carbonyl, 7r-cyclopentadienyl, and carbonyl hydride clusters, and references to these studies have been included in Tables II, VIII, and III, respectively. 

The conditions under which various types of compounds encountered in tracer work exchange with water are given in Tables IV, V, VI, VII, and VIII. These tables can be used as a guide in planning experiments, but in the last analysis, particularly in biocherhical reactions, parallel control experiments must be run to examine the possibility of isotopic... 

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