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Oxides of various

CgHeOa. White crystals m.p. 37°C, b.p. 263°C. Occurs associated with vanillin. Obtained on oxidation of various natural products such as piperine. Used extensively in soap perfumery. [Pg.316]

The oxidation of various thione compounds includmg thiazolinc-2-thiones has been reviewed (884). [Pg.397]

Products of Combustion Heat, hght, smoke, and asphyxiating and toxic gases are produced by fire. In a hot, well-ventilated fire, combustion is usually nearly complete. Nearly all the carbon is converted to carbon dioxide, all the hydrogen to steam, and oxides of various other elements such as sulfur and nitrogen are produced. [Pg.2314]

Compared with these methods, the palladium-catalyzed oxidation of 1-olefins described here is more convenient and practical. The industrial method of ethylene oxidation to acetaldehyde using PdCl2-CuCl 2-O2 original reaction of this type. The oxidation of various olefins has been carried out. ... [Pg.11]

The relation between tautomcrism and enzymatic oxidation of various hydroxypurines has been discussed by Bergmann and his associates. ... [Pg.59]

The effects on oxidation resistance of copper as a result of adding varying amounts of one or more of aluminium, beryllium, chromium, manganese, silicon, zirconium are described in a number of papers Other authors have investigated the oxidation of copper-zincand copper-nickel alloys , the oxidation of copper and copper-gold alloys in carbon dioxide at 1 000°C and the internal oxidation of various alloys ". ... [Pg.705]

As a further illustration, consider the oxidation of various substrates by S2Oj. Three chain mechanisms that are considered feasible are labeled Schemes C, D, and... [Pg.213]

An impressive indication of the high regioselectivity of hydroxysteroid dehydrogenases (HSHDs) was reported for the oxidation of various hydroxyl groups at the steroid core ofbile acids [26] (Scheme 9.1). The hydroxy-substituents at positions 3, 7, and 12 could be selectively addressed depending on the hydroxysteroid... [Pg.231]

For a list of references to the selective oxidation of various types of alcohol, see Kulkami, M.G. Mathew T.S. Tetrahedron Lett., 1990, 31, 4497. [Pg.1573]

In the same spirit DFT studies on peroxo-complexes in titanosilicalite-1 catalyst were performed [3]. This topic was selected since Ti-containing porous silicates exhibited excellent catalytic activities in the oxidation of various organic compounds in the presence of hydrogen peroxide under mild conditions. Catalytic reactions include epoxidation of alkenes, oxidation of alkanes, alcohols, amines, hydroxylation of aromatics, and ammoximation of ketones. The studies comprised detailed analysis of the activated adsorption of hydrogen peroxide with... [Pg.7]

Under microwave irradiation and applying MCM-41-immobilized nano-iron oxide higher activity is observed [148]. In this case also, primary aliphatic alcohols could be oxidized. The TON for the selective oxidation of 1-octanol to 1-octanal reached to 46 with 99% selectivity. Hou and coworkers reported in 2006 an iron coordination polymer [Fe(fcz)2Cl2]-2CH30H with fez = l-(2,4-difluorophenyl)-l,l-bis[(l//-l,2,4-triazol-l-yl)methyl]ethanol which catalyzed the oxidation of benzyl alcohol to benzaldehyde with hydrogen peroxide as oxidant in 87% yield and up to 100% selectivity [149]. An alternative approach is based on the use of heteropoly acids, whereby the incorporation of vanadium and iron into a molybdo-phosphoric acid catalyst led to high yields for the oxidation of various alcohols (up to 94%) with molecular oxygen [150]. [Pg.104]

Fig. 2. Relationship between the logarithms of the rate coefficients (Atj. 2) and the logarithms of the equilibrium constants (Jfi.i) for the oxidation of various substituted Fe(II)-phenanthroline complexes by Mn(III) in 1 A/ and 3 Af HCIO4 at 25.0 °C. (From Diebler and Sutin, by courtesy of The American Chemical Society.)... Fig. 2. Relationship between the logarithms of the rate coefficients (Atj. 2) and the logarithms of the equilibrium constants (Jfi.i) for the oxidation of various substituted Fe(II)-phenanthroline complexes by Mn(III) in 1 A/ and 3 Af HCIO4 at 25.0 °C. (From Diebler and Sutin, by courtesy of The American Chemical Society.)...
In conforming to an expected linear free energy relationship, the Ce(lV) oxidation of various 1,10-phenanthroline and bipyridyl complexes of Ru(II) in 0.5 M sulphuric acid are consistent with the requirements of the Marcus treatment . The results for the oxidation of the 3- and 5-sulphonic-substituted ferroin complexes by Ce(IV) suggest that the ligand does not function as an electron mediator, and that the mechanism is outer-sphere in type. Second-order rate coefficients for the oxidation of Ru(phen)j, Ru(bipy)3, and Ru(terpy)3 are 5.8x10, 8,8 X 10, and 7.0 x 10 l.mole . sec, respectively, in 0.5 M H2SO4 at 25 °C a rapid-mixing device was employed. [Pg.250]

The ferricyanide oxidation of various phenols has been examined by Waters et following the pioneering work of Conant et who observed... [Pg.434]

Table 30 lists some rate coefficients for oxidations of various free radicals. [Pg.493]

The bis amido complex [Au(bipy)(NHC6H4N02-4)2][Pp6] (43) has been similarly obtained by reaction of 40 with p-nitroaniline in acetone solution (Equation 2.14 in Scheme 2.6) [45b]. Complex 40 promotes the stoichiometric oxidation of various amines different from p-nitroaniline. Azotoluene is the main organic product of the... [Pg.68]

Oxides of various metals are a broad class of electrode materials useful in many electrochemical processes (Trasatti, 1980-1981). The surfaces of practically all metals (both base and noble) become covered by layers of chemisorbed oxygen upon anodic polarization. The composition and properties of these layers depend on potential, on the electrolyte, and on the electrolysis conditions. They are often rather thick and have a distinct phase character, so that the metal electrode is converted to a typical oxide electrode. One can also make electrodes directly from oxides deposited in some way or other on various conducting substrates. [Pg.544]

Figure 31 shows that among metal oxide supports, TOF markedly changes depending on not only the kind of metal oxides but also on their size [98]. Especially, fine particles of Ce02 with mean diameter of 5 nm present the highest catalytic activity. On the other hand, Prati and her coworkers [31] reported that gold NPs supported on activated carbons are very active and selective in the liquid phase oxidation of various alcohols. [Pg.196]

The percolation model of adsorption response outlined in this section is based on assumption of existence of a broad spread between heights of inter-crystalline energy barriers in polycrystals. This assumption is valid for numerous polycrystalline semiconductors [145, 146] and for oxides of various metals in particular. The latter are characterized by practically stoichiometric content of surface-adjacent layers. It will be shown in the next chapter that these are these oxides that are characterized by chemisorption-caused response in their electrophysical parameters mainly generated by adsorption charging of adsorbent surface [32, 52, 155]. The availability of broad spread in heights of inter-crystalline barriers in above polycrystallites was experimentally proved by various techniques. These are direct measurements of the drop of potentials on probe contacts during mapping microcrystal pattern [145] and the studies of the value of exponential factor of ohmic electric conductivity of the material which was L/l times lower than the expected one in case of identical... [Pg.72]

The experimental studies of the surface properties of monocrystals of oxides of various metals recently conducted at well-controlled conditions [32, 210] enable one to proceed with detailed analysis of separate effects of various factors on characteristics of semiconductor gas sensors. In this direction numerous interesting results have been obtained regarding the fact of various electrophysical characteristics of monocrystalline adsorbents on the value of adsorption-related response. Among these characteristics there are crystallographic orientation of facets [211], availability of structural defects, the disorder in stoichiometry [32], application of metal additives, etc. These results are very useful while manufacturing sensors for specific gases with required characteristics. [Pg.93]

Table 3 Recycle testing of 5%Pt,l%Bi/C for the selective oxidation of various alcohols. Conditions 15ml substrate / 15ml water, 60°C, 3 bar air. Table 3 Recycle testing of 5%Pt,l%Bi/C for the selective oxidation of various alcohols. Conditions 15ml substrate / 15ml water, 60°C, 3 bar air.
The use of heterogeneous catalysts in the liquid phase offers several advantages compared with homogeneous counterparts, in that it facilitates ease of recovery and recycling. A chromium-containing medium-pore molecular sieve (Si Cr > 140 1), CrS-2, efficiently catalyzes the direct oxidation of various primary amines to the corresponding nitro compounds using 70% t-butylhydroperoxide (TBHP).110... [Pg.20]


See other pages where Oxides of various is mentioned: [Pg.20]    [Pg.38]    [Pg.469]    [Pg.98]    [Pg.453]    [Pg.225]    [Pg.67]    [Pg.852]    [Pg.173]    [Pg.566]    [Pg.10]    [Pg.496]    [Pg.699]    [Pg.852]    [Pg.152]    [Pg.30]    [Pg.51]    [Pg.82]    [Pg.89]    [Pg.148]    [Pg.65]    [Pg.151]    [Pg.343]    [Pg.322]    [Pg.49]    [Pg.1319]    [Pg.782]    [Pg.420]   
See also in sourсe #XX -- [ Pg.179 ]




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Activities of various oxides

Electro-oxidation of Various Oxygenated

Oxidation potentials of various oxidants

Reactions of barium carbonate with various oxides

Solubility products of the various oxides

Spectra of the various Fe oxides

Various Growth Features of Ammonia-Oxidizing Bacteria

Various Mossbauer Spectroscopy Techniques in Study of Applications Related to Nanocrystalline Iron Oxides

Various Oxidation States of Transition Metals

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