Radiation field decomposition

Three-dimensional CFD-coupled with radiation field modeling and photocatalytic reaction dynamics was employed by Salvado-Estivill et al. (2007b) to model the decomposition of TCE in a flat-plate, single-pass photocatalytic reactor containing immobilized P25. The outcome was pollutant-specific kinetic rate parameters, which were independent of the reactor geometry, radiation field, and fluid dynamics. This was followed by... 

An attempt to prepare Np(BTif)if using the above method resulted in the decomposition of the borohydride due to the extremely high radiation field of the T2 gas (66 Ci) and no volatile Np compound was recovered. 

The organic-cooled CANDU concept was proposed by McNelly of CGE in 1958 (71), This began an extensive investigation of coolant properties, decomposition, control of deposition, and many other aspects of coolant chemistry. An organic-cooled, heavy-water-moderated research reactor, WR-1, began operation at WNRE in 1965. It has demonstrated reliable operation with coolant outlet temperatures of up to 675 K. Low corrosion and a low potential for activity transport result in very low radiation fields around the piping. 

The reprocessing of used reactor fuel elements involves solvent extraction processes with organic solvents. In these processes the solvents are subjected to high radiation fields with subsequent decomposition of the organic solvent. The design of chemical reprocessing systems must take into account any interference by the radiolytic products (Ch. 20). 

Nitric acid can be formed by the radiolysis of moist air. This nitric acid will rapidly dissolve in water and cause a decrease in the pH. On the other hand, intermediate products in the air radiolysis process interact rapidly with surfaces and other chemical species in the atmosphere. Furthermore, nitric acid is susceptible to decomposition in a radiation field. It has been difficult, then, to assess the overall effect nitric acid formation by radiolysis will have on solution pH. 

The Ea for the dissolution of hematite by mercapto carboxylic acids in acid media in the presence of UV radiation was lower (64 5 kj mol ) than that for dissolution in the absence of radiation (94 8 kJ mol ) (Waite et al. 1986). The reaction in both cases was considered to involve formation of an intermediate organic-Fe surface complex which decomposed as a result of intramolecular electron transfer to release Fe". UV irradiation enhanced the decomposition of the surface complex either through excitation of the ligand field states associated with the free electrons on the S atoms, or through high energy charge transfer states. 

Microfabrication by means of laser radiation covers a wide range of different methods (24,25). On the one hand, these are processes where material is removed in an intense electromagnetic field by melting, evaporation, decomposition, photoablation, or a combination of these phenomena. On the other hand, generating processes exist where structures are built up from liquid resins, laminated layers, or powders using, e.g., photochemically induced crosslinking of organic compounds... 

There are good reasons to believe that a strictly isolated molecule can be prepared experimentally in any (pure) state. " However, not all molecular states are equally stable under (small) external stochastic perturbations. The molecular environment is thus of decisive importance in all these discussions on molecular structure. Examples of environments that cannot be completely screened out are, e.g., quantum radiation and gravitational fields. Here an attempt is made to incorporate external environmental stochastic perturbations and to look for decompositions that are stable under these perturbations. This opens up a possible route to enable us to ... 

The problem of the action of radiation on azides, particularly lead and barium azide has been review cd [116]. Irradiation prior to thermal decom-Jposition often effects a reduction or elimination of the induction period, a de-ICrcasc in activation energy and an increase in the rate of decomposition. Zak-rov and co-workers [117] have found that the application of a moderate electric field can affect the rate of thermal decomposition of azides. 

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