Oxygen-containing species

This great variety of pathways makes it difficult to decide which of the steps is the rate-determining step. It is most likely that at intermediate current densities the overall reaction rate is determined by the special kinetic features of step (15.24) producing the oxygen-containing species. The slopes of = 0.12 V observed experimentally are readily explained with the aid of this concept. Under different conditions, one of the steps in which these species react further may be the slow step, or several of the consecutive steps may occur with similar kinetic parameters. 

The creation of additional sites with an enhanced adsorption of active forms of the oxygen-containing species involved in the slow oxidation step of the organic species chemisorbed on the platinnm snrface (bifnnctional mechanism of catalytic action) ... 

Tripkovic AV, Popovic KD, Lovic JD. 2001. The influence of the oxygen-containing species on the electrooxidation of the C-l-C alcohols at some platinum single crystal surfaces in alkaline solution. Electrochim Acta 46 3163-3173. 

As might be expected, the properties of polythiophene show many similarities with those of polypyrrole. As with polypyrrole, polythiophene can be prepared via other routes than electrochemical oxidation both as the neutral material [390-392] or in the p-doped form [393]. This material is produced as an infusible black powder which is insoluble in common solvents (and stable in air up to 360°C), with conductivities ranging from approximately 10 11 Scm-1 in the neutral form [390] to 102 Scm-1 when doped [19, 393, 394]. Early work on thiophene polymers showed that the p-doped material is air-sensitive in that the conductivity decreases on exposure to the atmosphere [20, 395] although no evidence of oxygen-containing species was seen in XPS measurements [19],... 

The complex Sn(OH)+ given here is purely formal since a further reaction could result in Sn(OH)2 or in the dehydrated form SnO. What shall be emphasized is that the theories explaining the catalytic effect of tin through oxygen-containing species can be justified by taking into account the chemical properties of Sn(II). 

In this way Sn(II) would bring oxygen-containing species to the Pt interface which are stronger adsorbed than HzO and can therefore act as oxygen donors more easily during methanol adsorbate oxidation ... 

Bismuth promotion suppresses the hydrogen sorption on platinum (curves b-d). The peak at -0.05 V indicates the oxidation of adsorbed bismuth, which overlaps the OH adsorption on uncovered platinum surface sites 18). Bismuth adatoms are discharged in the low potential region (Bi°) and occupy three platinum sites at low surface coverages. The structure of the oxygen-containing species are (BiOH), (BiO), and [Bi(OH)J,d 19). 

In addition to these larger VOCs, there are biogenic sources of a wide variety of small alcohols, aldehydes, ketones, and acids. For example, emissions of methanol and acetone have been reported from plant leaves, grass, and clover (e.g., MacDonald and Fall, 1993 Nemecek-Marshall et al., 1995 Fall and Benson, 1996 Kirstine et al., 1998). Table 6.25 shows some of the compounds measured in grass and clover emissions (Kirstine et al., 1998). Clearly, a wide variety of oxygen-containing species are emitted from this one source alone. Direct emissions of formaldehyde, ac-etaldehye, and formic and acetic acids have been observed from oaks and pines (Kesselmeier et al., 1997). 

Electropositive condiments. The name of a monoatomic electropositive constituent is simply the unmodified element name. A polyatomic constituent assumes the usual cation name, but certain well established radical names (particularly for oxygen-containing species such as nitrosyl and phosphoryl) are still allowed for specific cases... 

Photo-oxidation of PE and PP is mainly due to slight absorption of light above 285 nm by the commercial grades due to the presence of light-absorbing impurities, particularly oxygen-containing species, and trace levels of... 

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