Also found in: Dictionary, Wikipedia.


The moiety =CH-.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Previous works reported that the T1 relaxation values of liver methylene and methene groups were respectively between 0.39 to 1.20 s and 0.60 to 1.16 s [34, 35].
where [I.sub.methene], [I.sub.allylic], [I.sub.methylene], and [I.sub.methyl] are, respectively, the signal amplitude of the methene, allylic methylene, bulk methylene, and terminal methyl peaks.
UIs formula is based on the principle that methene functional group is always next to allylic methylene group in monounsaturated fatty acids and with both allylic and diallylic methylene groups in Poly Unsaturated Fatty Acids (PUFAs).
Compared with glycol chitosan, the new signal at 1.27 ppm belonged to methene hydrogen of cholesterol hemisuccinate group, indicating that CHGC conjugate was successfully synthesized [31, 32].
Table 1: Key Greenhouse Gases Affected by Human Activity (Percentage) Effect Carbon Nitrous dioxide Methene CFC Oxide Increase in atmospheric concentrations Pre-industrial to 1990 26 115 -- 8 1990-2025 23 51 -- 10 Contribution to the change in heat trapping Pre-industrial to 1990 61 23 12 4 1990-2025 68 17 10 5 Source: World Development Report 1992.
In a soil humic acid sample, they discovered some peaks attributed to methyl and methene that were invisible in normal 1-dimensional spectra because of presaturation.