Activity oxygen, effect

Avoilable Oxygen Active Oxygen Effective Oxygen Oxygen Botance to C03 and to CO. 

Available oxygen active oxygen, effective oxygen oxygen balance to C02 and CO 1 AS IS—AS 16 see Oxygen balance 8 057—062... 

It should be remembered that in this case, the active oxygen effect is displayed, when molecular oxygen is activated in the presence of another substance, the role of which is reduced to oxygen fixation and formation of an active site shaped as a complex or an intermediate... 

Polyall lene Oxide Block Copolymers. The higher alkylene oxides derived from propjiene, butylene, styrene (qv), and cyclohexene react with active oxygens in a manner analogous to the reaction of ethylene oxide. Because the hydrophilic oxygen constitutes a smaller proportion of these molecules, the net effect is that the oxides, unlike ethylene oxide, are hydrophobic. The higher oxides are not used commercially as surfactant raw materials except for minor quantities that are employed as chain terminators in polyoxyethylene surfactants to lower the foaming tendency. The hydrophobic nature of propylene oxide units, —CH(CH2)CH20—, has been utilized in several ways in the manufacture of surfactants. Manufacture, properties, and uses of poly(oxyethylene- (9-oxypropylene) have been reviewed (98). 

The effectiveness of antioxidants as preservatives for fats and oils is evaluated by determining the rate of peroxide development using the Active Oxygen Method (AOM) (29). The development of a rancid odor is used to evaluate the stabiUty of food items (Schaal Oven StabiUty test) (30). 

Tawa, R., and Sakurai, H. (1997). Determination of four active oxygen species such as H2O2, OH, OJ and 02 by luminol-and CLA-chemiluminescence methods and evaluation of antioxidative effects of hydroxybenzoic acid. Anal. Lett. 30 2811-2825. 

One-step hydroxylation of aromatic nucleus with nitrous oxide (N2O) is among recently discovered organic reactions. A high eflSciency of FeZSM-5 zeolites in this reaction relates to a pronounced biomimetic-type activity of iron complexes stabilized in ZSM-5 matrix. N2O decomposition on these complexes produces particular atomic oj gen form (a-oxygen), whose chemistry is similar to that performed by the active oxygen of enzyme monooxygenases. Room temperature oxidation reactions of a-oxygen as well as the data on the kinetic isotope effect and Moessbauer spectroscopy show FeZSM-5 zeolite to be a successfiil biomimetic model. 

Relatively detailed study has been done for the reaction pathways over Au/Ti02 catalysts mainly because of simplicity in catalytic material components. The rate of PO formation at temperatures around 323 K does not depend on the partial pressure of C3H6 up to 20vol% and then decreases with an increase, while it increases monotonously with the partial pressure of O2 and H2 [57]. A kinetic isotope effect of H2 and D2 was also observed [63]. These rate dependencies indicate that active oxygen species are formed by the reaction of O2 and H2 and that this reaction is rate-determining [57,63,64]. 

Peroxides, which are formed by the effect of hydrogen peroxide on hydrogen atom in a of active oxygen or on the alcohol group, can come into play in any of these reactions. 

The Ar-O-R aromatic ethers can give rise to reactions of electrophilic substitution that can be dangerous not only because of the reagents nature but also the activation effect due to the active oxygen. The activation mechanism can be described in the same way as for phenols. 

Niwa, Y., Soniya, K., Michelson, A.M. and Puget, K. (1985). Effect of liposomal-encapsulated superoxide dismutase on active oxygen-related disorders. A preliminary study. Free Rad. Res. Commun. 1, 137-153. 

Sofuni, T. and M. Ishidate, Jr. 1988. Induction of chromosomal aberrations in active oxygen-generating systems. I. Effects of paraquat in Chinese hamster cells in culture. Mutation Res. 197 127-132. 

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