Table 5 Comparison between final MCGA optimized and previously constructed5 \({\mathrm{UO_x}}\) mechanisms.
From: Stochastic optimization of a uranium oxide reaction mechanism using plasma flow reactor measurements
No. | Reaction | \(k^{{\textrm{a}}}_{mcga}\) | \(k_{lit}\) | ||||
|---|---|---|---|---|---|---|---|
A (cm\(^3\)/s) | n (–) | \(E_A/R\) (K) | A (cm\(^3\)/s) | n (–) | \(E_A/R\) (K) | ||
1 | \({\mathrm{U + O}} \rightleftharpoons {\textrm{UO}}\) | \(1.942 \times 10^{-11}\) | − 1.25 | 209.88 | – | ||
2 | \({\mathrm{U + O_2}} \rightleftharpoons {\mathrm{UO_2}}\) | – | \(3.360 \times 10^{-12}\) | 0.50 | 12910.0 | ||
3 | \({\mathrm{U + O_2}} \rightleftharpoons {\mathrm{UO + O}}\) | – | \(3.360 \times 10^{-12}\) | 0.50 | 5161.7 | ||
4 | \({\mathrm{U + OH}} \rightleftharpoons {\mathrm{UO + H}}\) | \(1.346 \times 10^{-13}\) | 0.32 | 5505.1 | – | ||
5 | \({\mathrm{U + H_2O}} \rightleftharpoons {\mathrm{UO + H_2}}\) | – | – | ||||
6\(^{{\textrm{b}}}\) | \({\mathrm{UO + O}} \rightleftharpoons {\mathrm{UO_2}}\) | \(1.950 \times 10^{-11}\) | 0.31 | 28020.3 | \(8.084 \times 10^{-13}\) | 0.27 | 3582.4 |
7\(^{{\textrm{b}}}\) | \({\mathrm{UO + O_2}} \rightleftharpoons {\mathrm{UO_3}}\) | – | \(4.325 \times 10^{-11}\) | − 0.23 | − 7503.5 | ||
8 | \({\mathrm{UO + O_2}} \rightleftharpoons {\mathrm{UO_2 + O}}\) | – | \(3.800 \times 10^{-11}\) | 0.17 | 0.0 | ||
9 | \({\mathrm{UO + OH}} \rightleftharpoons {\mathrm{UO_2 + H}}\) | \(1.309 \times 10^{-12}\) | − 0.56 | 2.03 | – | ||
10 | \({\mathrm{UO + H_2O}} \rightleftharpoons {\mathrm{UO_2 + H_2}}\) | \(1.488 \times 10^{-13}\) | 0.36 | 10422.0 | – | ||
11 | \({\mathrm{U + O}} \rightarrow {\mathrm{UO^+ + e^-}}\) | \(2.495 \times 10^{-14}\) | − 0.12 | 51.3 | \(1.025 \times 10^{-12}\) | 0.50 | 0.0 |
12 | \({\mathrm{U + O_2}} \rightarrow {\mathrm{UO_2^+ + e^-}}\) | – | \(7.747 \times 10^{-14}\) | 0.50 | 0.0 | ||
