Radiolytically generated hydrogen

The occurrence of fuel rod failures is often characterized by the initial appearance of very small perforations (pinholes). After prolonged operation of a Zircaloy-cladded defective rod, secondary hydride failures may develop, caused by hydrogen which is radiolytically generated from water vapor entering the rod via the primary defect. Such secondary failures may appear at a certain distance away from the primary defect (e. g. 1 m above it). Fretting failures also increase in size with time often they are located in the lower region of the fuel rod. Thus, the size of the failure as well as its location can differ considerably and it is important to identify these parameters already during the relevant fuel cycle. 

Chemerisov et al. report on radiolytically generated H atoms in water/ice clusters in NaA, NaX, NaY and HY zeolites. By FT EPR two states of spin-polarized hydrogen atoms with slightly different hfs constants were detected in NaY and HY zeolites, whereas in NaX and NaA zeolites only one H atom... 

A mathematical model of the operating characteristics of a modem HLW storage tank has been developed (60). This model correlates experimental data for the rate of radiolytic destmction of nitric acid, the rate of hydrogen generation owing to radiolysis of water, and cooling coil heat transfer. These are all functions of nitric acid concentration and air-lift circulator operation. 

Dai et al. (1990) have reported direct spectroscopic measurements on a similar bishomobenzene radical cation. The system they studied was the bicyclo[3.3.0]octa-2,6-diene-4,8-diyl radical cation [159] generated by radiolytic oxidation of semibullvalene [83] in Freon matrices. The hydrogen... 

The formation of hydrogen in the core also occurs by the radiolytic decomposition of water molecules, made of hydrogen and of oxygen. This phenomenon generates a mixture of hydrogen and... 

Hydroxyl radical. The —O—O— bond in hydrogen peroxide, at ca. 213 kJ/mole [7], is relatively weak, and is susceptible to homolysis by a variety of methods including thermal, photolytic/radiolytic and metal redox. The active species produced is the hydroxyl radical generation by UV irradiation at 254 nm giving two per mole of H2O2 ... 

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