The γ-radiolysis of water vapour

The photolysis of water vapor a t 1849 A has been investigated as a possible source of hydroxyl radicals for kinetic studies. At temperatures from 23 to 350' C and pressures from 1.3 t o 28 mm, H2 and H402 were the only detectable products. Experiments with added oxygen indicated that 0 2 ma37 have been present as a n intermediate a t a very low steady-state concentration, although this is not certain. Possible mechanisms are discussed. Ea2 -E C O = 4.0Zk0.3 kcal/mole, AH,/Aco = 3 1 f 5 , At temperatures below 200" C, hydroxyl radicals were not completely converted to COs, as the yield of Cop increased to a maximum, then decreased again, with increasing pressure of CO. The mechanism of this system is complex, but probably involves secondary reactions of HCO or COOH radicals.

“…In-the present system, concentrations of hydroxyl were probably orders of magnitude lower, and reactions such as [13], as H was probably much more abundant than HOz or OH.…”

Section: O + O H + O Z + Hmentioning

confidence: 99%

Section: O + O H + O Z + Hmentioning

confidence: 99%

The Photolysis of Water Vapor and Reactions of Hydroxyl Radicals

Ung¹,

Back²

1964

“…This is in marked contrast to the Pure water vapor undergoes little decomposition when exposed to ionizing radiation (1)(2)(3). In the presence of organic additives, however, the hydrogen yield greatly increases and a value for the total reducing species of G --8' has been obtained in H,O and D 2 0 containing various organic additives (2,4). The contributions of radical and ionic processes towards the yield of reducing species has been the subject of more recent publications (4)(5)(6).…”

Section: Introductionmentioning

confidence: 77%

“…Here x and y depend on the temperature and pressure and the concentrations of water and methanol in the mixture. In our experiments, therefore, reaction [2] will be replaced by…”

Section: Discussionmentioning

confidence: 99%

The X-radiolysis of water vapor containing methanol. Effects of some electron and hydrogen atom scavengers

Dixon¹,

Bailey²

1968

“…The y-ray radiolysis of mixtures of water vapor and a few mole percent of alkanes or alcbhols gives a hydrogen yield of G(H2) x 8 (molecules per 100 eV of absorbed dose) (1). This yield is reduced by --3 G units by the addition of an electron scavenger such as SF6 or N 2 0 (2, 3).…”

Section: Introductionmentioning

confidence: 99%

Radiolysis of water vapor with fission fragments

Boyd¹,

Miller²

1968

Water vapor, and mixtures of water vapor with radical and electron scavengers, have been irradiated with fission fragments a t temperatures from 170 to 365 "C and densities from 1-50 n~g / n~l .The unimolecular hydrogen yield is the same as in y-ray irradiations. In D20-C6HIz mixtures the HD yield and HD/H2 ratio are lower than in y-ray irradiations and N 2 0 and SF6 have little effect. The HD yield reaches a limiting value (G(HD) -4) with increasing linear energy transfer suggesting that a fraction of the D atoms formed are hot.