quinone

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quin·one

(kwin'ōn, kwī'nōn),
1. General name for aromatic compounds bearing two oxygens in place of two hydrogens, usually in the para position; the oxidation product of a hydroquinone.
2. Synonym(s): 1, 4-benzoquinone (1)

quinone

/qui·none/ (kwi´nōn) (kwin´ōn) any of a group of highly aromatic compounds derived from benzene or from multiple ring hydrocarbons and containing two ketone group substitutions; they are subclassified on the basis of ring structure (i.e., anthraquinone, benzoquinone) and are mild oxidizing agents. Often used specifically to denote benzoquinone, particularly 1,4-benzoquinone.

quinone

(kwĭ-nōn′, kwĭn′ōn′)
n.
1. Either of two isomeric unsaturated cyclic compounds having the formula C6H4O2, found widely in plants, especially in a yellow crystalline form, and used in making dyes, tanning hides, and photography.
2. Any of various quinonoid compounds, often yellow to red in color, many of which have biological derivation or importance, such as coenzyme-Q.

quinone

(1) 1,4-Benzoquinone, see there.  
(2) An aromatic compound with two oxygens substituted for two hydrogens.

quinone

any of the various compounds derived from benzene.
References in periodicals archive ?
95 Assignments C=C stretching/C-H bending modes of quinoid ring Band range C=C stretching/ C=N asymmetric stretching/C-H ([cm.
Considering that quinone methides are the resonance hybrids between the quinoid and benzenoid structures, and their high reactivity to electrophiles and nucleophiles, it is evident that the polycondensation mechanism in all catalytic conditions can be explained by their participation.
The UV-VIS spectra of the phosphate-doped polyaniline showed peaks at 330 nm for the [pi]--[pi]* benzenoid transition, and 630 nm for benzenoid to quinoid excitonic transition in agreement with literature.
1] for PPy is ascribed to -C=C stretching mode for quinoid and benzoid rings [27, 28].
This suggests the isolated polarons in the PSDA become an ordered polaron lattice in the p-PSDA [38], The broad bands at ca 560 nm of PSDA and 610 nm of p-PSDA were assigned to the local charge transfer between a negative charge centered on the quinoid ring and the positive charge centered on the benzenoid rings (charge transfer exciton).
1] corresponds to the quinoid ring units whereas lower frequency vibration band at 1476 [cm.
Toxicity of hvdroxylated and quinoid PCB metabolites: inhibition of gap junctional inter-cellular communication and activation of aryl hydrocarbon and estrogen receptors in hepatic and mammary cells.
Quinoid and benzenoid characteristic bands appear at 1500 and 1592 [cm.
1] correspond to the stretching vibrations of quinoid and benzenoid rings, respectively.
1] are assigned to the C-H in-plane deformation of the quinoid form (oxidized state) and benzoid form (reduced state) of PPy, respectively.
Yellowing is a result of photo-oxidation in the backbone chain through the aromatic ring by a quinoid path, leading to the degradation of PU and thus affecting the clarity and color of the material's surface (23).