Spectrophotometric study of uranium(VI) chelate formation with beta-diketones and tributyl phosphate in aqueous, nona(oxyethylene) dodecyl ether solution.
The distribution ratio of uranium(VI) with 2-thenoyltrifluoroacetone, 2-furoyltrifluoroacetone and benzoyltrifluoroacetone in the presence and absence of tributyl phosphate between micellar and bulk phases in nona(oxyethylene) dodecyl ether solution was measured spectrophotometrically as a function of hydrogen-ion concentration. The thermodynamic constants for these reactions were evaluated from the variation of the equilibrium constants as a function of temperature. The entropy change contributes to the synergistic reaction.
The Effect of Solvents on the Adduct Formation of Uranyl Thenoyltrifluoroacetonate with Tributyl Phosphate
Addition compound formation between uranyl bis-thenoyltrifluoroacetonate (UO2A2) and tributyl phosphate(S) was studied by a partition method, using uranium-237 as the tracer. The formula of the adduct complex was shown to be UO2A2·S. The solvent effect on the adduct formation constant was taken into account in connection with the activity; the activity coefficients of each species in various solutions were calculated from the molar volume and the solubility parameter. The formation constants based on the molar fraction, Kx, in a number of solvents were pre-estimated, employing logKx=7.08 in carbon tetrachloride as a reference. They are in agreement with the observed values. The formation constant in terms of activity was found to be constant logKS°=5.77±0.30. A correlation between the formation constants of the two adducts, UO2A2·S and ZnA2·S, was demonstrated.
Numerical Simulation of Thermal Sensitivity for Explosives
In order to compare the thermal sensitivity of several typical explosives, this article solved numerically one-dimensional transient heat conduction equation including thermal decomposition for explosives with finite difference method. The explicit difference equations under different boundary conditions were established, and the corresponding stability criterion was derived. The ignition times for typical explosives were calculated, which was used to evaluate thermal sensitivity of explosives.