Degradation of hydrogen peroxide

The use of UV light also facilitates the degradation of hydrogen peroxide and ozone. The most effective biocidal wavelength is 253.7 nm. The amount of light at 255 nm emitted by a UV light decreases with time, so lamps have to be monitored and replaced when necessary. 

Canbolat O, Fandrey J, Jelkmann W. 1998. Effects of modulators of the production and degradation of hydrogen peroxide on erythropoietin synthesis. Resp Physiol 114 175-183. 

Another enzyme which has been applied comparable times with horseradish peroxidase is catalase. Catalase is a heme protein belonging in the class of oxidoreductases vtdth fertiprotoporphyrin-IX that acts as the redox centre for the enzyme. As mentioned before, this enzyme catalyses the degradation of hydrogen peroxide by the feJlowii reaction ... 

Henzler, T. Steudle, E. (2000). Transport and metabolic degradation of hydrogen peroxide in Chara corallina model calculations and measurements with the pressure probe suggest transport of H2O2 across water channels. Journal of Experimental Botany, 51, 2053-2066. 

The activation energy in Eqs. 1.13 and 1.14 is lower than the activation energy of monomolecular degradation of hydrogen peroxides. Thus the oxidation of plastics is accelerated by the presence of metal ions. Relevant metal ions include iron (Fe y Fe " ), cobalt (Co yCo ), copper (CuyCu ), chromium (Cr yCr ), manganese... 

Metal ions then cause the degradation of hydrogen peroxides under formation of radicals. The damaging effect of metals can be minimized by complexing with suitable stabilizers (see Section 3.6.3). 

Aluminium is used in hydrogen peroxide (H.T.P.) processing and storage equipment partly because of its high corrosion resistance but also because it does not cause degradation of the peroxide. 

This discussion of the structures of diene polymers would be incomplete without reference to the important contributions which have accrued from applications of the ozone degradation method. An important feature of the structure which lies beyond the province of spectral measurements, namely, the orientation of successive units in the chain, is amenable to elucidation by identification of the products of ozone cleavage. The early experiments of Harries on the determination of the structures of natural rubber, gutta-percha, and synthetic diene polymers through the use of this method are classics in polymer structure determination. On hydrolysis of the ozonide of natural rubber, perferably in the presence of hydrogen peroxide, carbon atoms which were doubly bonded prior to formation of the ozonide... 

Exposure of protein amino groups to MDA (formed by the degradation of lipid peroxides) or to oxygen radicals directly, generated by transition metals and hydrogen peroxide, induce fluorescence indistinguishable from that attributed to Amadori-adduct formation (Chio and Tappel, 1969), and leads to the formation of cross-links (Lunec a al., 1985). 

Chand et al. [88] degraded phenol under sonication at different frequencies with H2O2 and O3 in presence of zero valent iron and copper. The effectiveness of 300 kHz sonochemical reactor was found to be the maximum for the generation of OH radicals among 20, 300 and 520 kHz. The complete removal of phenol was achieved when sonicated with 300 kHz frequency with zero valent iron compared to zero valent copper. In their mechanism it was supposed that at first iron metal was corroded in the presence of hydrogen peroxide, under acidic conditions, oxidizing Fe° to Fe2+, which on further reaction with H202 produce OH radicals and Fe3+. The Fe° then reduces the Fe3+ back to Fe2+ and the chain was maintained as... 

Metal-ion catalysis of hydrogen peroxide decomposition can generate perhydroxyl and hydroxyl free radicals as in Scheme 10.26 [235]. The catalytic effects of Fe2+ and Fe3+ ions are found to be similar [235]. It is not necessary for the active catalyst to be dissolved [237], as rust particles can be a prime cause of local damage. The degradative free-radical reaction competes with the bleaching reaction, as illustrated in Scheme 10.27 [237]. Two adverse consequences arise from the presence of free radicals ... 

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