Yields of radiolysis products from γ-irradiated supercritical water—A re-analysis data by W.G. Burns and W.R. Marsh

Radiation influence on the temperature-dependent parameters of fluids

Based on the fundamental Bogolyubov chain of equations, a model relating the structural and thermophysical properties of the nonequilibrium liquid systems under irradiation in stationary state is introduced. The obtained results suggest that the thermophysical properties of the liquid systems under irradiation are defined by the "effective temperature" that can be calculated from the perturbed momentum distribution functions of the systems. It is shown that the structural changes in the liquid systems under irradiation are caused by the changes in the coefficients of the Maxwell distribution function due to the momentum exchange between the active particles and the particles forming the liquid. To confirm the theoretical predictions, a qualitative comparison of the model with the existing experimental data on irradiation influence on the surface tension coefficients of liquids is performed.

Radiolysis of supercritical water at 400 °C and liquid-like densities near 0.5 g/cm3 — A Monte Carlo calculation

Monte Carlo simulations are used to calculate the primary radical yields [Formula: see text], g(•OH), the sum [[Formula: see text] + g(•OH) + g(H•)], and the ratio g(H•)/[Formula: see text] in the low linear energy transfer (LET) radiolysis of supercritical water (SCW) at 400 °C in the high-density, liquid-like region near ∼0.5 g/cm3. Using all the currently available information on the reactivities and diffusion coefficients of the radiation-induced species under these conditions, and assuming the aqueous medium to be a “continuum”, a good accord is found between our calculations and the available experimental data. In particular, our computed [Formula: see text] yields at 60 ps and 1 ns compare very well with recently reported direct time-dependent [Formula: see text] yield measurements in SCW (D2O) at 400 °C and 0.570 g/cm3 using picosecond pulse radiolysis experiments.