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 (kwĭn′ə-noid′, kwĭ-nō′-)
Of or containing quinone or resembling it in structure or properties; quinoid.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈkwɪnəˌnɔɪd; kwɪˈnəʊnɔɪd) ,




(Dyeing) of, resembling, or derived from quinone
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈkwɪn əˌnɔɪd, kwɪˈnoʊ nɔɪd)

of or resembling quinone.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
On the other hand, pristine PPy is insoluble, infusible, brittle, and amorphous due to the rigidity of its molecular chains from the quinoidal and aromatic states.
Xu, "Direct visual evidence for quinoidal charge delocalization in poly-p-phenylene cation radical," The Journal of Physical Chemistry B, vol.
For instance, when phenolic stabilizers decompose (either by radical transfer reactions with a polymer macroradical or by oxidation), they may form byproducts such as quinoidal compounds that greatly discolor the material [31].
Segura-Aguilar, "Quercetin may act as a cytotoxic prooxidant after its metabolic activation to semiquinone and quinoidal product," Free Radical Biology and Medicine, vol.
Semiquinones transfer electrons to molecular oxygen ([O.sub.2]) and return to their original quinoidal structure, thus generating a superoxide anion radical ([O.sub.2.sup.-*]).
Com relacao a estabilidade das antocianinas, as mesmas se encontram comumente na forma de uma mistura de diferentes estruturas quimicas em equilibrio: cationflavilium (vermelho), base anidra quinoidal (azul), pseudobase carbitol (incolor) e chalcona (incolor ou levemente amarela).
The great interest in its study, including the elucidation of mechanisms of action of compounds with quinoidal structure is due to their multiple biological targets and their widespread presence in nature (Hussain et al., 2007).
A Reinvestigation of the quinoidal effect in N-n-propyl-2-oxo-1-naphthylidene-methylmine, Acta Crystallogr., C52, 2573-2575(1996).
This process of deterioration is mediated by endogenous enzymatic activities such as polyphenol oxidase (PPO) and peroxidase (POD), which leads to the formation of dark polymers of a quinoidal nature (ESCRIBANO et al., 2000; FRICKS et al., 2006; PEREZ-TELLO et al., 2001; VALENTINES et al., 2005; ZHOUA et al., 2003).
Under the conditions described above the quinoidal forms for para- and ortho-species can be assigned by characteristic chemical shifts in [sup.13]C NMR spectra [7].