hydrogen donor

(redirected from Active hydrogen)

hy·dro·gen do·nor

a metabolite from which hydrogen is removed (by a dehydrogenase system) and transferred by a hydrogen carrier to another metabolite, which is thus reduced.

hy·dro·gen do·nor

(hī'drō-jen dō'nŏr)
A metabolite from which hydrogen is removed (by a dehydrogenase system) and transferred by a hydrogen carrier to another metabolite, which is thus reduced.

hydrogen donor

In oxidation-reduction reactions, a substance that gives up hydrogen atoms to another substance, the acceptor.
See: hydrogen acceptor
See also: donor
References in periodicals archive ?
Contract notice: procurement of active hydrogen maser
It undergoes various chemical reactions to replace hydroxyl, active hydrogen and amino groups, which makes it valuable in the chemical industry.
Active hydrogen produced in equation 2 is at low concentrations and the amount is not sufficient to terminate all of the radical chains formed from heavy oil components.
A rubber composition comprising: (A) a conjugated diene rubber which is obtained by polymerizing a conjugated diene compound or polymerizing a conjugated diene compound and an aromatic vinyl compound and has a group having an active hydrogen and a group capable of chemically binding to a silica, (B) a silica, (C) a silane coupling agent (1) capable of reacting with a carbon-carbon double bond of the conjugated diene in the conjugated diene rubber, and (D) a silane coupling agent (II) capable of reacting with the group having an active hydrogen; a method for producing a rubber composition, which comprises mixing the above-mentioned composition; and a tire which is obtained by crosslinking and molding the rubber composition obtained by the method for production.
Nevertheless, the potential Michael addition reactions cannot be ruled out because each BTA molecule contains two >NH groups and one >[CH.sub.2] group and the active hydrogen atoms of these functional groups may lake part in the polymerization of BMI with BTA via the Michael addition reaction mechanism.
This may have relations with the enhancement to aggregation by hydrogen bonding formation by the active hydrogen atom in polar protic solvents.
The hydrogen donor additives releases free active hydrogen that react with the active chain free radicals produced during pyrolysis of the heavy oil, thereby inhibiting the regress of upgraded oil viscosity (Curtis and Cassell, 1988; Ovalles, et al., 1998; Liu and Fan, 2002).
Nearly all the major vehicle manufacturers have active hydrogen research and development programmes.
The argument was based on the fact that since CP needs to first break down to produce hydrogen peroxide, given relatively long active bleaching time sessions, active hydrogen peroxide derived from the 20%CP can remain in contact with the enamel surface past the degradation time of all or most of the active bleaching activity of 7.5%HP.
Long term performance is equal to UTC at 5x[10.sup.-14] offset over 3...33 days as measured against an ensemble of active hydrogen masers and NIST + NPL traceable by satellite time transfer techniques.
Isocyanate compounds are usually highly reactive toward molecules containing an active hydrogen entity.
However, if an active hydrogen activation catalyst which results in hydrogen atom addition to condensed aromatic centers can be found, more distillable liquids could be formed relative to the quantity of gases.