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Simmons, E. L.

Publications and source records attributed to Simmons, E. L..

Oxygen and hydrogen atom concentration profiles in the premixed propane/oxygen flame

The oxygen and hydrogen free radical (atom) concentration profiles in the premixed propane/oxygen flame at 92.5% oxygen were determined using electron spin resonance (ESR) spectroscopy techniques. The ESR instrument was specially modified so that the flame can be probed for determining the oxygen and hydrogen atom population densities during the actual combustion process of propane burning in oxygen. The technique used for propane is similar to that suggested by Fristrom and Westenberg to measure the free radical concentration profiles in C-C hydrocarbon/oxygen combustion.

Downs, W. R.↗

Relation of the diffuse reflectance remission function to the fundamental optical parameters.

The Kubelka-Munk equations describing the diffuse reflectance of a powdered sample were compared to equations obtained using a uniformly-sized rough-surfaced spherical particle model. The comparison resulted in equations relating the remission function and the Kubelka-Munk constants to the index of refraction, the absorption coefficient, and the average particle diameter of a powdered sample. Published experimental results were used to test the equation relating to the remission function to the fundamental optical parameters.

Simmons, E. L.↗