Oxidation studies

Conclusions from recent studies of the mechanism of the oxidation of carbons by molecular oxygen have been presented which suggest that the initial part of the reaction pathway involves the interaction of the oxygen molecule with a spin centre in the carbon, with the formation of a peroxy-radical (03). The next stage involves the dissociation of this species into two atomic species C(0)j, which are thought to be mobile over the carbon surfaces. It is from these dissociated species that the products of the oxidation, 

Watanabe, H. Takenaka, arid M. Takashima, Nippon Kagaku Kaishi, 1973, 487. 

It is concluded that XPS allows an effective means of determining the type of carbon present and the results of any effective oxidation. 

The reaction of ozone with carbons has been the subject of three investiga-tions. The kinetics of the gas-solid reaction at ambient temperature 

The products of reaction (2) can lead to subsequent surface changes, yielding CO2  

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Manufacture of oBenzoylbenzoic Acid from l-Methyl-3-phenylindane. In 1909 it was reported that treatment of styrene with concentrated sulfuric acid resulted in its dimerization (51). However, the wrong stmcture was assigned to this dimer (52). Years later it was suggested, without proof, that the dimer consisted primarily of l-methyl-3-phenylindane (13) [6416-39-3] and some 1,3-diphenyl-l-butene (53). In 1950, oxidative studies on the dimer proved that this supposition was correct (54) ... 

Gulf of Maine Oxidant Study (GOMOS) a study to investigate the sources and transport of pollutants contributing to ozone formation. 

The results observed in the oxidation of alkaloids which indicated something of the stereochemistry required for oxidation and prompted studies on model systems can now be interpreted more confidently. However, care must be used when basing steric differentiation on mercuric acetate oxidation studies since conditions must be employed which avoid epimerization at carbons alpha to the nitrogen. 

The oxidation of aluminium at room temperature is reported to conform to an inverse logarithmic equation for growth periods up to 5 years duration. At elevated temperatures, oxidation studies over shorter periods illustrate conformity to parabolic, linear and logarithmic relationships according to time and temperature. These kinetic variations are attributed to different mechanisms of film formation . ... 

Investigations of gas-phase processes in the presence of fiber catalysts focused on oxidation, SGR, and synthesis of chemicals. Oxidation studies of CO [68-71],... 

In the second oxidation method, a metalloporphyrin was used to catalyze the carotenoid oxidation by molecular oxygen. Our focus was on the experimental modeling of the eccentric cleavage of carotenoids. We used ruthenium porphyrins as models of cytochrome P450 enzymes for the oxidation studies on lycopene and P-carotene. Ruthenium tetraphenylporphyrin catalyzed lycopene oxidation by molecular oxygen, producing (Z)-isomers, epoxides, apo-lycopenals, and apo-lycopenones. 

Hess, C. and Lunsford J.H. (2002) Mechanism for N02 Storage in Barium Oxide Supported on Magnesium Oxide Studied by in Situ Raman Spectroscopy,./. Phys. Chem. B, 106, 6358. 

K. Jacobsson, P. Eriksson, T. Reitberger, B. Stenberg, Chemiluminescence as a tool for polyolefin oxidation studies, In A.C. Albertsson (Ed.), Long Term Properties of Polyolefins, Advances in Polymer Science, Springer, 2004, Vol. 169, p. 151. 

It has been known that the basal graphite plane (graphene hexagon) is chemically inert. However, CNTs are susceptive to some chemical reactions due to the it-orbital mismatch in the curvature structures. Oxidation studies have revealed that the tips (caps) of CNTs are more reactive than the cylindrical parts [8, 20], Ab initio calculations indicate that the average charge density of a pentagon (at the tips) is 3 4 times larger... 

Pacsu4 5 has suggested a structure for starch involving a small number of non-cyclic hemiacetal linkages, the number being presumably sufficient to account for the number of endgroups determined by the methylation method. Halsall, Hirst and Jones6 have commented on this structure, however, and have shown it to be incompatible with the results of periodate-oxidation studies. In addition, these authors pointed out that it would be difficult to explain enzymic hydrolysis and dextrin formation on the basis of such a structure. 

In Table 15 are recorded the dissociation constants of certain phenolic compounds. From these data it becomes obvious that the introduction of aldehyde groups, or other substituents, changes the dissociation constant of phenolic hydroxyls by over one-hundred fold. Moreover, oxidation studies carried out in this laboratory have shown that the native lignins from bagasse, white Scots pine and birch contain... 

Saib, A. M., Borgna, A., van de Loosdrecht, J., van Berge, P. J., and Niemantsverdriet, J. W. 2006. In situ surface oxidation study of a planar Co/SiO2/Si(100) model catalyst with nanosized cobalt crystallites under model Fischer-Tropsch synthesis conditions. J. Phys. Chem. B 110 8657-64. 

For 2,3 5,6-di-O-isopropylidene-a-D-mannofuranose (183), separation of the anomeric products (184 and 185) was possible,135 and their structures were elucidated by periodate-oxidation studies. The configurational assignment for these products was based on the greater value of the specific rotation for the a anomer, as compared with that of the j3 anomer. The higher chromatographic mobility of one of the... 

The D-galactosyl residues are the same as in disaccharide 33, and the fact that ribitol is substituted at 0-2 was evident from the methyl-ation analysis. Finally, a nonreducing tetrasaccharide was obtained, containing D-galactose, 2-acetamido-2-deoxy-D-galactose, and ribitol residues in the proportions 2 1 1. From these results, and periodate-oxidation studies, structure 36 was proposed for the neutral hexa-saccharide. 

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