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(ˈkwɪn ɔɪd)
1. quinonoid.
2. a quinonoid substance.
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The number before the resorcinol symbols in the description of the molecular structure indicates the number of the corresponding resorcinol moieties or oxidation products in the molecule; O indicates C-O coupling (grey background); qqq marks the third quinoid structure in the molecule; confirmed molecular formulas with mass accuracy < 5 ppm are in bold; nd--not detected; dna--data not analysed.
Determination of selective quinones and quinoid radicals in airborne particulate matter and vehicular exhaust particles.
In Flavonoids Due to oxidation of one aromatic ring into quinoid form, shows different colour in different colour in different mediums such as red chelates absorption shows finding of flavonoids.
Therefore, vulcanization systems may include organic accelerators along with resins, zinc oxide, zinc oxide and sulfur, and quinoid systems.
On the other hand, the reaction mechanism of para substitution would depend on the formation of an activated complex from the quinoid form (Yeddanapalliand Gopalakrishna, 1959).
However, formation of quinoid metabolites of black cohosh was demonstrated only in vitro but not in vivo (Johonson and van Breemen, 2003).
The latter two xenobiotics are converted to quinoid derivatives, which are, in principle, able to participate in redox cycle and generate active oxygen species.
transition and the band in the visible region corresponds to the inter-ring charge transfer associated with excitation from benzenoid to quinoid moieties.
Very often [3] it is supposed that quinoid transition forms are important in P/F polycondensation.
1] assignable to out-of-plane C-H bond, aromatic C-N-C bond, aromatic C = C bond, (8) and nitrogen bond between benzoid and quinoid rings, respectively.
Quinoid redox cycling as a mechanism for sustained free radical generation by inhaled airborne particulate matter.