Abstract:New methods to calculate the acceleration ability of detonation products and the detonation energy of explosives with the cylinder expansion test data were applied to determine the performance characteristics for some high explosives of military interest. The obtained results were also compared to the calculation results with CHEETAH code. Moreover, the detonation pressure for chosen explosives was evaluated on the basis of a variation of the cylinder test in which a cylindrical water layer was loaded by detonation wave propagating along an explosive charge confined by the water envelope. Results of the tests and thermochemical calculations were used to deduce constants of the JWL equation of state. Finally, the JWL isentropes obtained were applied to calculate the theoretical expansion work of detonation products.

Abstract:The experiments of vapor cloud explosion were carried out respectively in which the hemispherical strip barrier and the global pouched barrier were set. The pressure-time curve was recorded by system consisted of pressure transducer,A/D card and computer with less than one millisecond. A program was designed to calculate the explosion impulse of observed spot on the basis of pressure-time curve,and the effects of the characteristic parameters of barriers on the explosion impulse were studied. The experimental results show that the explosion impulse increases with interspaced ratio,vapor cloud radius,and barrier radius. The relationship between impulse and distance in the hemispherical vapor cloud is approximate cosine. Moreover,a fitting equation to calculate explosion impulse of hemispherical vapor clouds was proposed by applying multi-energy model.

Abstract:The fuel dispersion and initiation of single-event FAE (SEFAE) is self-harmonious. The very short delay-time between fuel dispersion and initiation is adverse to make good use of the oxygen in atmosphere for detonation of SEFAE. Therefore,experimental study on single-event FAE were made with adding solid oxidizer to the fuel (KClO₄,NH₄ClO₄) to improve the power of SEFAE. The results show that (1) the oxygen in fuel clouds zone is abundant to oxidize the fuel of SEFAE completely,whereas,for the original solid multi-component fuel mixture,the oxygen in atmosphere is not utilized effectively,and the energy of SEFAE do not release thoroughly; (2) adding NH₄ClO₄ to the original solid multi-component fuel mixture improves the power and stability of SEFAE,and the optimum content of NH₄ClO₄ in this kind single-event FAE is 15%.

Abstract:In the numerical modeling of divergent detonation, the matched relationship between the viscosity and the mesh size was studied in terms of the Lee-Tarver′s reaction rate and JWL equation of state. The results indicate that the artificial viscosity is higher near the center and tends to be one dimensienal plane far from the center. Moreover,spherical divergent detonation of PBX-9404 explosive was simulated. And the results are in agreement with the characteristics of divergent detonation.

Abstract:The Ba₂(H₂TNP)₂(OH)₂(H₂O)₂］·(CH₃CH₂OH)·2.5H₂O (H₂TNP: 3,5-dihydroxy-2,4,6-trinitrophenolate) complex was prepared by mixing barium nitrate solution and sodium H₂TNP solution, which was obtained through the reaction of sodium bicarbonate and trinitrophloroglucinol. The molecular structure was characterized by using element analysis, IR analysis and X-ray diffraction. The complex 1 crystallizes in tetragonal system, space group I4(1)/amd, with crystal parameters a=19.911(3) nm,b=19.911(3) nm,c=13.265(3) nm,V=5259.0(15) nm³,Z=8, R=0.0335 with 1092 reflections. The structure consists of a barium dimmer unit held together by two oxygens bridging. Each Ba atom is 10-coordinated with eight oxygen atoms from four H₂TNP, an oxygen atom from water molecule and a coordinated hydroxy ion. In complex the metal atoms are linked via oxygen bridges to infinite networks structure. Uncoordinating water molecules and ethanol molecules are present in the cavities of the crystal structure. The thermal decomposition of the complex is studied using differential scanning calorimetry (DSC), thermogravimetry-derivative thermogravimetry (TG-DTG) and IR techniques. The final residue is BaCO₃ at 550 ℃.

Abstract:A new energetic material compound 3-amino-4-aminoximinofurazan(AAOF) with yield of 72.4% was synthesized by using dicyanopropane as initial material through 4-step continuous reaction by one-pot method. Its molecular structure was characterized by IR,MS,¹H-NMR,¹³C-NMR,elemental analysis and UV. A 500 gram-grade synthesis procedure of 3-amino-4-aminoximinofurazan (AAOF) was realized on the basis of the optimized procedure. The synthesis reaction mechanism of AAOF was theoretically deduced and validated .

Abstract:The catalyst of rare earth(Ⅲ) perfluorooctanesulfonates(RE(OPf)₃, RE=La, Sm, Eu, Tb, Yb, Lu) were prepared for the nitration of toluene in fluorous biphasic system. Perfluorohexane (C₆F₁₄), perfluoro- methylcyclohexane (C₇F₁₄), perfluorotoluene (C₇F₈), perfluorooctane (C₈F₁₈), perfluorooctyl bromide (C₈F₁₇Br) or perfluorodecalin (C₁₀F₁₈, cis and trans-mixture) were used as fluorous solvent respectively for this reaction. Effects of rare earth metal salts with different ligands and amount of the catalyst on the reaction were studied. The results show that Yb(OPf)₃ and C₁₀F₁₈ are the best catalyst and fluorous solvent respectively. The yield of nitration of toluene is 56% by using Yb(OPf)₃ as a catalyst and C₁₀F₁₈ as a fluorous solvent, and para-selectivity is 45%; By simple separation of the fluorous phase containing only catalyst, nitration can be repeated many times.

Abstract:By means of Gaussian 98 packages software at the level of B3LYP/6-31G,the structure of tetraacetylhexaazaisowurtzitane(TAIW) was optimized and calculated. The theoretical analysis of the structure of TAIW,such as bond length,bond angle,dihedral angle and charge was performed. Judging from the analysis,the amine in the hexa-ring is active. And the solvent-effect on TAIW′s stabilization is large. Moreover,the calculated and the experimental IR harmonic frequenceies,intensities of TAIW are listed,and the relative-error of harmonic frequenceies is less than 4%.

Abstract:Ultrasonic cavitation treatment of polymer bonded explosive (JB-1) was undertaken. Before and after treatment,the surface structure of JB-1 explosive was observed by scanning electron microscope (SEM),and its element concentration was analyzed by X-ray energy spectrum (EDS). The results show that the interface between explosive crystal and binder is debonding during the ultrasonic treatment,and explosive crystals appear on the surface. With the treatment time increasing, the exposed extent of explosive crystal and the number of micro-hole on the surface of explosive crystal increase. As the surface of JB-1 explosive become rough and loose after ultrasonic cavitation treatment,its initiation sensitivity may also increase.

Abstract:Steven tests for two explosives PBX-2 and PBX-1 were made by using a steel projectile of 2.0 kg. The pressure change was measured by pressure gauges,and ignition delay time was estimated and analyzed by high-speed motion pictures. The reaction overpressure of two explosives were gained by blast pressure gauges. The results show that the threshold velocities of ignition for explosives PBX-1 and PBX-2 range from about 35.0-35.5 m·s^-１ and 40-46 m·s^-１ respectively,and the ignition delay time of PBX-1 explosive is smaller than that of PBX-2 explosive remarkably,which demonstrates that PBX-1 explosive is more sensitive than PBX-2 explosive.

Abstract:In order to solve the low precision of delay-time and bad long-storage property of delay composition,the delay-time precisions of B-BaCrO_４　delay composition pressed by wet method and dry method were studied with high-low temperature test and long-storage test. The results show that the delay-time precision of B-BaCrO₄ delay composition pressed by wet method is better than that by dry method at the room temperature,high or low temperature （-6 ℃,60 ℃）or in long-storage test（70 d）.

Abstract:The nano-size Pb(Ⅱ)-phthalate was prepared with potassium phthalate and Pb(Ac)₂·3H₂O by ultrasonic liquid dispersion deposition method. The effects of reaction temperature,reactant concentration,dispersant quantity on particle size of Pb(Ⅱ)-phthalate were studied. The nano Pb(Ⅱ)-phthalate with particle size of 43 nm was obtained at 10 ℃ with concentration of 0.4 mol·L^-1,and dispersant quantity of 8%. Moreover,the catalysis of nano-size Pb(Ⅱ)-phthalate for double-base propellant (DB propellant) was studied. It is found that nano Pb(Ⅱ)-phthalate increases burning rate of DB propellant at 2-22 MPa and make DB propellant emerge mesa effect at 6-10 MPa. Compared with common Pb(Ⅱ)-phthalate,nano Pb(Ⅱ)-phthalate enabled the burning rate of propellant to be higher than that of propellant including common Pb(Ⅱ)-phthalate,and its pressure exponent is lower at 6-10 MPa.

Abstract:The locus equation for the pellet′s shiver of smoke projectile was established by using the air friction and the gravitation, and the solving process of equation was presented. The exploding process of smoke projectile was shot by a high speed camera. Test data were used to obtain related coefficients, and the mathematical model was modified further. The results illustrate that air friction effect on the flying locus of shiver is significant.

Abstract:The heat treatment of polymer bonded explosive PBX-03 with Φ20 mm×10 mm was carried out at 50 ℃,and was characterized by ultrasonic characteristic value. Some new information about the effect and mechanism of heat treatment on PBX-03 was obtained. The results show that the ultrasonic characteristic values of the specimens display a unified tendency during the heat treatment,and the adequate heat treatment is helpful to improve the internal quality of PBX-03,and the irreversible growth of TATB in PBX-03 is probably the main reason causing the results above.

Abstract:The aging mechanism of rigid polyurethane foams at indoor storage conditions was investigated with indoor storage tests,accelerated hygrothermal aging tests and IR spectra. The results show that compressive stress at 10% strain and amino formic acid ester index decrease with aging time. It indicates that the hydrolysis of ester group is the main reason resulting in the decrease of compressive property of rigid polyurethane foams at indoor storage conditions.

Abstract:The immobilized anaerobic sludge ball was prepared by using chitosan as embedding agent,and waste water containing TNT was degraded by using upflow anaerobic sludge bed. Experimental results show that the upflow anaerobic sludge bed is fast to be started,stable to be operated,and that much less sludge is produced and the removal rate of TNT is 75.76%-94.76%.

Abstract:The concentrations of tetroxide dinitrogen （N₂O₄）and pentoxide dinitrogen（N₂O₅） and nitric acid in N₂O₄-N₂O₅-HNO₃ system are measured by the chemical titration and the nuclear magnetic resonance spectra (NMR)combining titration,respectively. And its results from two methods were compared. The effects of the oxidants,the solvents and the sampling methods on the concentrations of N₂O₄,N₂O₅ analyzed by the chemical titration were also investigated. The results indicate that both the NMR combining titration and titration are in agreement and accurate for the analysis of N₂O₄-N₂O₅-HNO₃ system. N₂O₄ concentrations analyzed by using cerium sulfate as oxidant are more accurate than that of potassium hypermanganate as oxidant. The results of sampling by using ampoule ball are better than that of sampling by using pipette. Comparing with the aqueous solutions of sodium hydroxide as solvent to analyze N₂O₅ concentration,distilled water used as solvent gives the higher accuracy and the better repeatability.

Abstract:The two electrochemical synthesis of N₂0₅ by oxidation of N₂O₄ and by dehydration of HNO_３ are reviewed, and the comparison between these two methods is given by analyzing the current efficiency, the specific energy, the current density and the chemical yield of the electrolytic process. The importance of cell membrane and the electrode affecting the current efficiency and the specific energy of the electrolysis are presented, and the evaluations of the cell membranes and the electrode materials suitable for the electrolytic system are given. The development and prospect on the research of N₂O₅ are proposed either.

Abstract:Several methods of preparing nanocomposites energetic materials in liquid phase by using sol-gel chemistry,spray route,precipitation and freeze-drying are reviewed. Metal-oxide-based nanocomposites energetic materials are prepared mainly by sol-gel,and the preparation of Fe₂O₃/Al nanocomposites is illustrated. Spray route including spray drying and Rapid Expansion of Supercritical Solution (RESS) instead of solvent with CO₂ supercritical fluids are introduced,mainly by which nanocomposites with energetic materials and nanostructured metal particles are prepared. Precipitation and Compressed Fluid Antisolvent (PCA) instead of precipitation reagent with CO₂ supercritical fluids are also given. Composites with inorganic oxidizer and nanostructured metal particles are prepared by freeze-drying,and NH₄ClO₄/Al nanocomposites is illustrated.

Abstract:The synthesis methods of furoxan derivatives were reviewed. The preparation methods of 3-amino-4-azidocarboxyl-furoxan as the precursor of furoxan derivatives,were summarized as well as the feasibility of all these methods. The synthesis ways of phenyl furoxan derivatives,i.e. pyrogenation of azido and o-nitro group in benzene ring,oxidation of substituted o-nitroaniline,oxidation of the CC double bond bonding with phenyl directly were also described.

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