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The gasochromic mechanism in amorphous tungsten oxide films has been investigated using Raman scattering measurements. The Raman spectra of as-deposited films show two strong peaks at 770 and 950 cm−1 due to vibrations of the O–W6+–O and W6+=O bonds, respectively. When the Pd/a-WO3 films are gasochromically colored by exposure to diluted hydrogen gas, extra Raman peaks due to O–W5+–O and W5+=O bonds appear at 330 and 450 cm−1, respectively. The Raman spectra of a-WO3 films bleached with isotopic heavy oxygen (18O) show that the gasochromic coloration in a-WO3 films is directly related to the double injection of hydrogen ions and electrons.

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The reaction of hydrogen peroxide with the copper-zinc bovine-liver superoxide dismutase at low molar ratios (0.2-20.0) of HzOz/active site between pH 7.3-10.0 leads to the loss of native enzyme as a distinct form monitored by electrophoresis. The pH dependence of the loss of native enzyme between 7.3 and 9.0 indicates the involvement of a conjugate base on the enzyme of pKa of 8.7 0.1. The rate of loss of the native enzyme is first order with respect to the concentration of both enzyme and hydrogen peroxide between pH 7.3 and 9.0 with no evidence for binding of peroxide. A second-order rate constant of 3.0 i 1.0 M-l s-' is obtained from these data.

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