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Thermochemical and Performance Properties of NO2-Substituted Borazines as New Energetic Compounds with High Thermodynamic Stability

Zamani M., Keshavarz M. H.

Central European Journal of Energetic Materials

2014

Vol. 11, no. 3

363--381

The structural isomers of nitroborazines were optimized at M062X/6-311++G** level of theory. The effects of the NO2 group on the molecular volume, molecular surface area, crystal density, positive, negative and total average potentials, variances, average deviation and electrostatic balance parameter on the molecular surface were considered. In addition, some important thermodynamic properties of these compounds, such as gas phase and condensed phase enthalpies of formation (ΔfH° (g) and ΔfH° (c)), and the enthalpy of sublimation (ΔH° sub), were calculated. It was found that the crystal densities (ρ) are in the range 1.4471.902 g/cm3. These values are slightly smaller than the corresponding values of their carbon analogues (except for the mononitro compounds). Meanwhile, the values of ρ for B-substituted, di- and trinitroborazines are larger than the related N-substituted compounds. The calculated values of ΔH° sub are in the range 20.1-30.4 kcal/mol. The calculated values of ΔfH° (g) and ΔfH° (c) for the B-substituted nitroborazines are more negative than those for the N-substituted ones. The stability sequence of the hydrogen bonded network structures of nitroborazines in the condensed phase is: dinitroborazine > mononitroborazine > trinitroborazine. The detonation pressure and velocity of these compounds were also calculated. Nitroborazines can be introduced as energetic compounds with high thermodynamic stability and relatively low detonation performance.

Letter of intent: investigation of the fission before K-equilibration

Jokić S., Vorkapić D., Ivanisević B., Kelić A., Todorović Z., Savović S., Botchev B., Zamani M., Fernandez F.

Nukleonika

1998

Vol. 43, nr 3

275-279

We propose to study mass resolved fission fragment anysotropies and mass resolved neutron multiplicities for the (sup 12)C + (sup 232)Th and (sup 16)O + (sup 232)Th reactions at 74 MeV and 85 MeV laboratory energy, respectively. For (sup 12)C + (sup 232)Th and (sup 16)O + (sup 232)Th reaction we expect at lower energies the larger difference between angular anisotropy at symmetric and angular anisotropy at asymmetric division. The measurement of neutrons in coincidence with mass resolved fission fragments will enable to calculate mass resolved angular anisotropy with neutron correction taken into account. We could also expect possible angular anisotropy of pre-scission neutrons. We expect less neutrons in the fission fragment direction.

W pracy zaproponowano badanie anizotropii fragmentów rozszczepienia i krotności neutronów w zależności od masy w reakcji (sup 12)C + (sup 232)Th i (sup 16)O + (sup 232)Th przy energii w układzie laboratoryjnym odpowiednio 74 i 85 MeV. Oczekujemy w przypadku tych reakcji przy niskich energiach, że różnica między anizotropią kątową w przypadku symetrycznym i niesymetrycznym będzie większa (...). Możemy również oczekiwać anizotropii kątowej neutronów przedrównowagowych oraz mniejszej liczby neutronów w kierunku rozlotu fragmentów rozszczepienia.