Hydrogen peroxide concentration, effect

FIGURE 7.3 A schematic illustration of hydrogen peroxide concentration effect on material removal rate of copper with the addition of complexing agent such as glycine and passivating agent such as BTA (from Ref. 11). 

Cotton linters and viscose grade wood pulp were grafted with acrylamide using the xanthate method. The effects of monomer concentration, reaction time, hydrogen peroxide concentration, reaction temperature, and liquor ratio on the grafting process were studied. Optimum conditions for the grafting reaction were established [26]. 

Figure 5 Effect of hydrogen peroxide concentration on grafting yield and grafting efficiency, wood pulp.

Philippou, J.L., Johns, W.E. and Nguyen, T. (1982). Bonding wood by graft polymerisation. The effect of hydrogen peroxide concentration on the bonding and properties of particleboard. Holzforschung, 36(1), 37-42. 

Effect of Hydrogen Peroxide. Hydrogen peroxide had two different effects on lignin peroxidase. Firstly it caused a lag time in the assay of activity. The length of the lag time before the onset of the reaction varied depending on the hydrogen peroxide concentration, pH and contact time. After the lag time the reaction star-... 

The oxidation of a trialkylborane may be effected by per-benzoic acid or by aqueous hydrogen peroxide in the presence of alkali.20 A detailed systematic study of the reaction parameters (oxidation temperature, base concentration, hydrogen peroxide concentration) of the latter method has led to the development3 of a standard and common procedure for oxidizing organoboranes, and is illustrated in the present procedure. 

The relationship between radiation intensity and effective treatment rate might not be universally applicable to all substrates, especially when treatment parameters change. For example, when a more concentrated substrate solution was treated at various peroxide concentrations, a higher radiation level did not increase the decomposition rate however, when a less concentrated substrate solution was treated, there appeared to be some treatment system efficiency improvement at higher radiation intensity. Equation (7.1) shows that UV intensity is proportional to the concentration of hydroxyl radicals produced at constant hydrogen peroxide concentration. 

In order to quantify this effect of a shifting relative contribution of mechanisms 1 and 2 as a function of the hydrogen peroxide concentration, a factor, x, is introduced. This factor depends only on the hydrogen peroxide concentration and is equated to 1 if only mechanism 1 would occur and is equated to zero if only mechanism 2 would occur. By means of this parameter, x, it appears possible to combine Equation 4.49 with Equation 4.52 and to transform it into the same relation. 

For the purpose of determining low hydrogen peroxide concentrations, the authors have designed the most cost-effective and simple to use potentiometric-biomimetic sensors based on immobilized catalase mimics. These sensors possess high hydrodynamic properties and the fastest speed of response. Figure 8.3 shows experimental data on catalase activity of biomimetic electrode in 0.03% aqueous H202. For the sake of comparison, catalase activities of aluminum electrode and aluminum electrode with applied adhesive are also shown. 

Oxidation of iron(II) ions to iron (III) oxidation occurs slowly upon exposure to air. Rapid oxidation is effected by concentrated nitric acid, hydrogen peroxide, concentrated hydrochloric acid with potassium chlorate, aqua regia, potassium permanganate, potassium dichronate, and cerium(IV) sulphate in acid solution. 

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