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The kinetics of the reaction between has been studied under conditions of production of iodine at a known rate by the persulfate-iodide reaction and its consumption by S2O3 -- . The effective concentration of iodine during the steady state is measured from its reduction potential at a bright platinum foil electrode. The reaction is of first order with respect to I3 - and S2O3 -- individually and hence of over all second order. The specific rate is 1.51 X 105 M -1 sec-1 and the frequency factor is 1.69 × 1012 M -1 sec-1 at 25 °C. The energy of activation for the reaction is 9.58 × 103 cal/mole and the entropy of activation is -2.55 cal/mole deg.

Theoretical curves of the voltage dependence of cathodoluminescence have been obtained for the case where the intensity of cathodoluminescence varies superlinearly with the net carrier generation rate. Calculations are based on numerical integration of the distribution of excess carriers assuming a Guassian approximation to the distribution of excitation with depth. The theoretical curves make possible the measurement of diffusion lengths using the method of voltage dependence of cathodoluminescence in specimens where the intensity of cathodoluminescence is not linearly proportional to the specimen current (e.g., p‐type GaAs). Experimental results with accelerating voltages of 5–50 kV using a defocused electron beam and selected area technique indicate values of electron diffusion length in p‐type GaAs ranging from 3.2 μ at low carrier concentration (6.9×1016 cm−3) to 0.6 μ at high carrier concentration (3.76×1019 cm−3).

Kinetics of ester-interchange between methyl acetate and ethanol has been studied in the range 80 - 105°, using gas chromatographic technique. The reaction is of the second order, and the specific reaction rate is 29.6-10-8 l/mole-sec at 105°. The energy of activation is 16.7 kcal/mole and the en-tropy of activation is -44.3 cal/mole-deg.