JOURNAL OF ENERGETIC MATERIALS
Year:2011 | Volume:6 | Issue:1 (11)|Papers Count:8

The salts of 3-Nitro-1, 2, 4-triazol-5-one (NTO) have received much attention in recent years due to their great application as energetic ballistic modifiers for solid propellants and gun propellant formulations. In this work, thermal behavior of four new amine salts of NTO among dimethyleguanidine, diethyleguanidine cyclohexamethylenetetramine and semicarbazide were studied under a non-isothermal condition by DSC and TG-DTG methods. The kinetic parameters (Arheniuse) were obtained from analysis of the DSC and TG curves by the Agrawal, Satava-Sestak and Ordinary-integral methods and the enthalpies of decomposition of the amine salts of NTO were calculated. The results in terms of activation energy showed that amine salts of NTO are thermally more unstable than NTO and show different thermal decomposition mechanisme.

In this paper, the H-point standard additions method (HPSAM) is evaluated for the spectrophotometric analysis of two component mixtures. Synthetic mixtures of the antioxidant bis (4-methyl-2-tert-butyl hydroxyl phenyl) methane (A.O.2246) and its phenolic intermediate (2-tert-butyl-4-methyl phenol) were used for this study. Two wavelengths of 274.8 and 290.6 nm were optimized for determination of intermediate as analyte and the antioxidant A.O.2246 as interference. This work demonstrates the advantage of HPSAM method for solving the matrix and spectra interference and shows the linear relationship between concentration and absorbance in the range of 0.4 to 80 micro molar.

By using of multilayer targets instead of monolithic layer one with equal total thickness; it is possible to increase the perforation ballistic resistance. As a result, for the same perforation ballistic resistance, the total thickness of the multilayer targets would be smaller. In this paper, a new analytical model for oblique penetration of blunt projectile into the multilayer metallic target is developed using the plastic stress wave propagation theory and equation of momentum. The base of this model is Felli’s model for oblique penetration of blunt projectile into monolithic layer target. The penetration processes are defined in nine stages. The first stage is cavity expansion in the target and then penetration continues with plug formation. For each stage, equations of motion for projectile and target are derived and solved to obtain penetration parameters. The analytical results of this paper are in good agreement with experimental results of the other investigators.

In this researche, effect of lateral liquid Freon injection on the thrust vector deviation is investigated. For this purpose, variation of different parameters as liquid injection from injector in to the nozzle and its effect on the trust deviation are considered. In this system, some of the most important parameters are; injection mass flow rate, angle injection, position injection and main flow rate from nozzle to the main flow. Simulation of flow field has been done using Fluent 6.2.16 software and for result validation, some experimental data have been used. The results shows that the optimum position of injection is about 35-40 percentage of divergent nozzle length from throat position, angle of injection has negligible effect on deviation of thrust vector and optimum values of mass flow injection depend on position of injection.

In the present work, the JCZ3 equation of state is used to calculate the equilibrium properties of high explosive detonation products. The JCZ3 equation of state is based on statistical thermodynamic concepts and its coefficients are the coefficient of molecular potential function. As the parameters of JCZ3equation of state are not limited to special conditions (pressure and temperature), so it is expected that this equation of sate can be used in a wide range of conditions. The results show that the accuracy of the JCZ3 equation of state in calculating the properties of high explosive CJ properties is the same as BKW equation of state. In addition, the accuracy of the JCZ3 equation of state in calculating the properties of detonation in low pressures is conform to the results obtained via the equation of state of ideal gas. The current results indicate that accuracy of the results with JCZ3 equation of state in the calculation of detonation properties at medium pressure are better than BKW and ideal gas equation of state.

In this paper various factors that effected on separation of mono and di substituted nitro toluene compounds was investigated by gas chromatography method and optimum separation condition was reported for 2-nitrotolouen (2NT), 4-nitrotolouen (4NT), 2,3-dinitrotolouen (2,3DNT),  2,4-dinitrotolouen (2,4DNT), 2,6-dinitrotolouen (2,6DNT)  and 3,4-dinitrotolouen (3,4DNT) compounds. Optimum carrier gas flow rate and injection volume was 20-30 ml.min-1 and 0.3 t1, respectively. Isothermal separation method wasn’t accepted for given good results and then programming mode (T1=80 OC, t1=6S, scan rate=30, T2=240, t2=6s) was used.

The hydrogenation kinetic of NDMA to UDMH on a 5% Pd/C in aqueous solution of NDMA was studied and optimum conditions of the reaction for maximum yield of UDMH in the presence of undesired dimethyl amine (DMA) product was investigated. Experiments were carried out in a semi-batch three phase stirred tank reactor under constant pressure of 15 bar, temperature of 40 to 70°C and NDMA concentration of 40 to 70 wt%. Effects of temperature, pressure and NDMA concentration on yield of UDMH product in presence of undesired dimethylamine (DMA) were studied and the optimum conditions for selective production of UDMH were obtained. For these optimum conditions, a kinetic scheme based upon Eley-Rideal (ER) model was proposed to predict UDMH and DMA production rates. Based on this model, the reaction parameters for these two products were estimated and the activation energies of these two reactions were determined.