The adsorption of 1,1-diamino-2,2-dinitroethylene （FOX-7） molecule on the AI（I 11） surface was investigated by the generalized gradient approximation （GGA） of density functional theory （DFT）. The calculations ...The adsorption of 1,1-diamino-2,2-dinitroethylene （FOX-7） molecule on the AI（I 11） surface was investigated by the generalized gradient approximation （GGA） of density functional theory （DFT）. The calculations employ a supercell （4 × 4 × 2） slab model and three-dimensional periodic boundary conditions. The strong attractive forces between oxygen and aluminum atoms induce the N--O bond breaking of the FOX-7. Subsequently, the dissociated oxygen atoms and radical fragment of FOX-7 oxidize the AI surface. The largest adsorption energy is --940.5 kJ/mol. Most of charge transfer is 3.3 le from the A1 surface to the fragment of FOX-7 molecule. We also investi- gated the adsorption and decomposition mechanism of FOX-7 molecule on the AI（111） surface. The activation en- ergy for the dissociation steps of P2 configuration is as large as 428.8 kJ/mol, while activation energies of other configurations are much smaller, in range of 2.4 to 147.7 kJ/mol.展开更多
The thermal decomposition kinetics of composite modified double-base （CMDB） propellants with a series of contents of hexogeon （RDX） was investigated by using parameters of Tco, Ti, Tp, Tf, Tb, Ta, E, lg A and AH, ...The thermal decomposition kinetics of composite modified double-base （CMDB） propellants with a series of contents of hexogeon （RDX） was investigated by using parameters of Tco, Ti, Tp, Tf, Tb, Ta, E, lg A and AH, which were obtained from using a CDR-4P differential scanning calorimeter （DSC） and Perkin-Elmer Pyris l thermogravimetric analyzer （TG） analyses with heating rates of 5, 10, 15 and 20 K/min. Reliable activation energy was calculated using Flynn-Wall-Ozawa method before analyzing the thermal decomposition mechanism. TG-DTG curves were treated with Malek method in order to obtain the reaction mechanisms. The obtained results show that the thermal decomposition mechanisms with the conversion from 0.2 to 0.4 was f（a）= 1/2a, and with the conversion from 0.5 to 0.7 was f（a）=（1/4）（1--a）[--1n（1 --a）]-3.展开更多
文摘The adsorption of 1,1-diamino-2,2-dinitroethylene （FOX-7） molecule on the AI（I 11） surface was investigated by the generalized gradient approximation （GGA） of density functional theory （DFT）. The calculations employ a supercell （4 × 4 × 2） slab model and three-dimensional periodic boundary conditions. The strong attractive forces between oxygen and aluminum atoms induce the N--O bond breaking of the FOX-7. Subsequently, the dissociated oxygen atoms and radical fragment of FOX-7 oxidize the AI surface. The largest adsorption energy is --940.5 kJ/mol. Most of charge transfer is 3.3 le from the A1 surface to the fragment of FOX-7 molecule. We also investi- gated the adsorption and decomposition mechanism of FOX-7 molecule on the AI（111） surface. The activation en- ergy for the dissociation steps of P2 configuration is as large as 428.8 kJ/mol, while activation energies of other configurations are much smaller, in range of 2.4 to 147.7 kJ/mol.
文摘The thermal decomposition kinetics of composite modified double-base （CMDB） propellants with a series of contents of hexogeon （RDX） was investigated by using parameters of Tco, Ti, Tp, Tf, Tb, Ta, E, lg A and AH, which were obtained from using a CDR-4P differential scanning calorimeter （DSC） and Perkin-Elmer Pyris l thermogravimetric analyzer （TG） analyses with heating rates of 5, 10, 15 and 20 K/min. Reliable activation energy was calculated using Flynn-Wall-Ozawa method before analyzing the thermal decomposition mechanism. TG-DTG curves were treated with Malek method in order to obtain the reaction mechanisms. The obtained results show that the thermal decomposition mechanisms with the conversion from 0.2 to 0.4 was f（a）= 1/2a, and with the conversion from 0.5 to 0.7 was f（a）=（1/4）（1--a）[--1n（1 --a）]-3.
