Search

A practical and brilliant way of preparing laser energetic coordination polymers based on crystallization chemistry and coordination theory is proposed in this paper. Design and successful synthesis of urazine (C

A better understanding of semiconductor bridge (SCB) discharge behavior under different firing conditions was crucial to revealing the mechanism of the SCB ignition technique. In this paper, the te...

The synthesis of four neutral 4-nitro-5-(1,2,4-triazol-3-yl)-2H-1,2,3-triazole compounds in combination with different energetic moieties like amino, nitrimino, nitro, and azo groups is presented. Furthermore, a novel family of energetic salts based on the 4-nitro-5-(5-R-1,2,4-triazol-3-yl)-2H-1,2,3-triazole (2: R = nitrimino; 3: R = nitro) monoanion and dianion were controllably synthesized. All new compounds were fully characterized by IR and multinuclear NMR spectroscopy, elemental analysis and DSC measurements. The molecular structures of 2, 3, 8 and 17 were determined by single-crystal X-ray diffraction. In addition, the heats of formation and detonation performance of all the energetic compounds were calculated using Gaussian 09 and EXPLO5 v6.01 programs, respectively. Both experimental and theoretical evaluations show promising properties for these energetic compounds, such as high density, positive heats of formation, high thermal stabilities, good sensitivities and excellent detonation performances. Among them, 6, 7, 14 to 16, 24 and 25 exhibit favorable overall properties as energetic materials.

The molecular and crystal structures of ethylenediamine triethylenediamine tetraperchlorate (SY) have been determined by XRD. The compound crystallizes in the orthorhombic system (space group Cmc21) with cell dimensions a =8.1030(16), b =24.725(5) and c =10.195(2) A. Band structure and density of states (DOS) were calculated by a Dmol 3 method. The first principle tight-binding method within general gradient approximation (GGA) has been used to study the electronic band structure as well as density of states (DOS) and Fermi energy.

This paper is concerned on the interaction of SCB plasma with Lead Azide, Lead Styphnate (LTNR) and Nickel Hydrazine Nitrate (NHN) primary explosive particles, with emphasis on the effects which the heat of explosive imposes on heat transfer from SCB plasma. The heat transfer from SCB plasma to a single spherical particle is calculated by simple calculation method. The effect of the ion and electron recombine reaction at particle’s surface and a spot of explosive reaction during the heating process was discussed. The results with a relatively simple analysis showed that the effect of particle charging on the heat transport to a particle from SCB plasma is not significant especially for the small particles. The effect of the heat of explosive on heat transfer to a particle is stronger for explosive materials with lower activation energy and larger heat of explosive or higher density.

The process of non-plasma ignition of lead styphnate by a silicon-based semiconductor bridge is studied. Discharge characteristics with plasma and non-plasma ignition are analyzed. It is demonstrated that non-plasma ignition is characterized by a low energy and can be applied in cases with fine-grain energy materials.

The characteristics of semiconductor-bridge (SCB) plasma in the air have been studied. Based on the double line of atomic emission spectroscopy principle, a system for the research of SCB plasma is designed and developed. With this technique, SCB plasma temperature is diagnosed, and the standard deviation is less than 9%. Moreover, plasma temperature distribution Vs time is acquired, and the temporal resolution is 0.1 mus. In addition, voltage and current signal above the SCB during the fire shot are monitored. These results indicate that the duration of SCB plasma is about 100 ms and the temperature changes dramatically in the air. The relation among plasma late time discharge, excitation energy, and plasma temperature is considered. Bridge shape and firing circuit also affect the plasma duration and plasma temperature.