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A Note on the Kinetics of Diffusion-mediated Reactions
The prevalent scheme of a diffusion-mediated bimolecular reaction
is an adaptation of that proposed by Briggs and Haldane for
enzyme action [{\em Biochem J.\/}, 19:338--339, 1925]. The purpose of this Note
is to explain, {\em by using an argument involving no mathematics\/}, why the
breakup of the encounter complex cannot be described, except in special
circumstances, in terms of a first-order process .
Briefly, such a description neglects the occurrence of re-encounters, which lie
at the heart of Noyes's theory of diffusion-mediated reactions. The relation
k=\alpha k_{\mbox{\scriptsize e}} becomes valid only when (the
reaction probability per encounter) is very much smaller than unity
(activation-controlled reactions), or when (the re-encounter
probability) is negligible (as happens in a gas-phase reaction). References to
some works (by the author and his collaborators) which propound the correct
approach for finding are also supplied.Comment: 4 pages, 1 figur
Failure analysis of the lithium battery: A study of the header deposit on the cell top and diffusion within the electrode glass seal using nuclear microanalysis and FFTIR spectroscopy
The Solid Rocket Booster Range Safety System (SRBRSS) uses a lithium/poly-carbon monofluoride primary battery as a source of electrical power. After cell fabrication and activation, some battery cells have shown self discharge. One possible source of this cell discharge has been suggested to be the formation and growth of a conducting crystallized chemical compound across the glass bead insulator, electrically shorting the glass bead to the casing. This laboratory has begun an analysis of this compound, the glass seal holding the cathode into place, and the cell electrolyte, using Fast Fourier Transform Infrared (FFTIR) Analysis, Rutherford Backscattering Spectroscopy (RBS), and Nuclear Reaction Microanalysis. Preliminary measurements have confirmed the existence of lithium, nitrogen, fluorine, and oxygen on a reddish-brown deposit covering parts of the glass seal holding the positive electrode in place. Cells using Li metal electrodes, have many advantages over conventional primary batteries. One principal disadvantage of using Li batteries on a commercial basis would be the environmental impact of the fluorocarbon material. Another would be the relatively high expense of (CF)n
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