Abstract:Pyrotechnic composition is a kind of propellants and explosives. The development of pyrotechnic composition in China has endured long history,as a breakthrough,it is used in the high-tech war against for passive optical interference in the late 20th century,then the new phase of theoretical research and technological innovation is emerging in the 21st century. New infrared illuminants,pyrotechnic pulse signal agents,sonar decoy agents,extended-range projectiles at the bottom of the exhaust agents,light radiation blind interference pyrotechnics,put out the burning or deflagration of the pyrotechnic soft kill,“cold” pyrotechnics,minimum smoke/smokeless pyrotechnic agent have distinctive characteristics of innovation and development. The breakthrough of the theoretical study on pyrotechnics,technology concept updates,the expansion of applied research fields,new research highlights the principle of new materials,new technology and safety and environmental protection and dual-use were embodied in the formulation design are the developing directions of pyrotechnics in the future.

Abstract:The density functional theory（DFT） was used to study molecule and crystal of bis-(5-nitro-tetrazolato) tetraammine cobalt (Ⅲ) perchlorate (BNCP). DFT calculations of BNCP were performed using four different spin-restricted functionals (SVWN5,PBE,TPSS and B3LYP) with the 6-31G^**as the basis set. The results show that the TPSS (Tao,Perdew,Staroverov and Scuseria) functional best reproduce the experimental geometries. At the same time,the crystalline of BNCP was studied by PW91 of DMOL³. Then,the electronic structure of molecule and density of state,lattice energy,thermodynamic parameters of BNCP crystal were explored. The results show that the metal-ligand interaction in the title complex is covalent. And the frontier band consisted in the main of perchlorate ion,so it is the most active part of the compound. Meanwhile,the relationship between the temperature and thermodynamic parameters was obtained.

Abstract:N-Methyl-N-(2-nitroxyethyl)nitramine (Me-NENA),N-ethyl-N-(2-nitroxyethyl)nitramine (Et-NENA) and N-butyl-N-(2-nitroxyethyl)nitramine (Bu-NENA) were prepared by the reactions of methyl ethanolamine,ethyl ethanolamine,butyl ethanolamine and nitric acid,acetic anhydride respectively. The structure of the target products were identified by ¹H NMR,IR and elemental analysis. The parameters affecting the yield and purity of Et-NENA,such as temperature,reaction time,nitric acid and acetic anhydride were discussed. The optimum conditions were given: n(ethyl ethanolamine)：n(nitric acid)：n(acetic anhydride)=1：2.6：2.4,the reaction temperature of the first stage 5-10 ℃,the second reaction temperature 40-45 ℃,reaction time 15 min,yield of Et-NENA was over 84.70% and the purity of the refined product was over 98.07%. The physical,chemical,safety properties and thermol decomposition of alkyl-NENAs have been experimentally studied.

Abstract:1-Methyl-3,5-dininitro-1,2,4-triazole (MDNT) was synthesized from hydrazine dihydrochloride and cyanoguanidine via a three step procedure (condensation cyclization,diazotization nitration,and methylation). The total yield is 16.75%,melting point is 95-96 ℃，and purity is more than 99% for the purified MDNT. The structure of the obtained MDNT was characterized by ¹H NMR,IR and elemental analysis. The extraction of 3,5-diamino-1,2,4-triazole (DAT) by hot methanol improved DAT′s yield from 89.0% to 96.5%. The thermal decomposition of MDNT proceeds in two stages. The corresponding peak temperature is 95.7 ℃ and 230.2 ℃,and decomposition heat is 16.505 kJ·mol^-1and 112.582 kJ·mol^-1,respectively.

Abstract:Chloropolyether terminated polybutadiene(CTPB) was synthesized with hydroxyl terminated polybutadiene(HTPB) as initiator and boron-trifluoride etherate as catalyst by cationic ring-opening polymerization of epichlorohydrin. Epoxy terminated polybutadiene(ETPB) with epoxy value of 0.0549 was synthesized by ring-closing reaction of CTPB under basic conditions. The effects of NaOH/CTPB molar ratio,reaction temperature and reaction time on ring-closing reaction were discussed. Curing procedures of different curing agents on ETPB were examined. Results show that polyamide 650 is good curing agent of ETPB. The tensile strength and elongation of the cured sample is 4.5-5.1 MPa and 150%-180%,respectively.

Abstract:3-Amino-4-amidoximinofurazan(AAOF) was synthesized from dicyanopropane by a two-step procedure. By the investigation of reaction parameters on AAOF′s yield,the appropriate reaction conditions listed below: nitrosation temperature 5-10 ℃,oximation temperature 25 ℃,dehydration cyclization temperature 105 ℃ and pH of reaction solution 7-8. The overall yield can be up to 95% and purity 98.5%. The obtained AAOF′s molecular structure was confirmed by IR,¹H NMR,¹³C NMR and elemental analysis. Besides,AAOF was proved to be thermal stable,and its thermal decomposition peak temperature is 203.44 ℃ measured by TG/DTG technique.

Abstract:3,5-Diaminopyridine (DAP) and 3,5-dimethoxycarbonylaminopyridine (DMAP) were synthesized from 3,5-dimethylpyridine via a three-step reaction(oxidation,ammoniation and Hofmann degradation) with the yields of 70% (for DAP) and 72% (for DMAP). This procedure possesses advantages of mild conditions,easy operation,high yield and environmentally-friendly. A number of influencing factors for each step were investigated and discussed. The intermediates and target compounds structures were characterized by ¹H NMR,MS/MS,IR and elemental analysis.

Abstract:One novel hydroxyl-terminated block copolyether(PTHF-PEO-PTHF)was synthesized by tetrahydrofuran cationic ring-opening polymerization and linkage of polytetrahydrofuran with two terminals of polyethylene glycol (PEG),using PEG as macroinitiator,boron-trifuoride ethylether complex (BF₃·OEt₂) as catalyst,and epoxy propane(PO)as assistant ring-opening . The obtained copolyether was characterized by IR and ¹H NMR. Moreover,polyurethane elastomers were prepared with hydroxy terminated polyether （HTPE）,and the elastomers have satisfactory mechanical properties,low glass transition temperature(T_g=-69.03 ℃),and good thermal stability. These can meet the requirements of binder for solid propellant.

Abstract:Two kinds of resemble sphere and cubic crystals of 2,6-diamino-3,5-dinitropyrazine-1-oxide(LLM-105) were prepared using solvent-nonsolvent recrystallization technology. The average particle (D₅₀) is 2.750 μm and 6.206 μm,impact sensitivity(H₅₀) is 35.5 cm and 34.7 cm,respectively. Thermal properties of LLM-105 were analyzed with thermogravimetry-derivative thermogravimetry（TG-DTG） and differential scanning calorimetry（DSC）. Thermal decomposition kinetics parameters of LLM-105 were obtained by Kissinger equation. The value of activation energy,pre-exponential factor and linear correlation coefficient is 257.55 kJ·mol^-1,3.3×10¹⁹ s^-1 and 0.9930,respectively.

Abstract:It is helpful for understanding reaction zone and equation of state(EOS) of reactant to study divergent detonation and grazing detonation driving abilities. TATB based explosive and HMX based explosive were investigated with bigplate experiment and numerical simulation. Results show that for the larger radius of velocity interferometer system for any reflector(VISAR) probe,the higher final flyer velocity,implying more effective charge. Obtained JWL(Jones-Wilkins-Lee) parameters can reproduce the cylinder test results quite well. It can be concluded that VISAR method is effective for initial acceleration moment,and for the later movement period,both VISAR and smear photograph technique data can be used for the determination of detonation product EOS at cylinder test.

Abstract:Velocity interferometer system for any reflector (VISAR) interferometer was used in bigplate experiment to measure the movement of the flyer. The measured places of VISAR are: 0,10,20,40 and 80 mm,the corresponding angles of incidence are decided: 0°,4.5°,7.5°,10° and 11.5°. Results show that the velocity curves measured at different places are completely. The effective time of measuremnet is from 8 μs to 12 μs. VISAR testing technology with slanting incidence is feasible.

Abstract:It is very important and instructive for us to further investigate the formation mechanism of hot spots in explosive initiation in wide pressure zone. Magnetically driven quasi-isentropic compression (shock less compression) is an effective method to research the dynamic behaviors of un-reacted explosives in high pressure. Based on the working principle of electro-magnetic force produced by large current,the shockless compression technique driven by magnetic force is first achieved in domestic. A pressure of 5 GPa is obtained in the experiments of magnetically driven quasi-isentropic compression. The particle velocities of the interface between JO-9159 explosive and LiF windows are gained. The isentropic compression procedure was numerically simulated by one dimensional hydrodynamics code. The simulated particle velocities are in good agreement with experimental results. The gradient of particle velocities between the windows and the samples becomes larger when samples become thicker. The strain ratios of the samples are in 10⁵/s~10⁶/s, and the peak of strain ratio becomes narrower but higher when samples become thicker.

Abstract:The Cowan equation of state and thermodynamic parameters of copper and cobalt were investigated. Accordingly,the detonation parameters of BNCP(tetraamminebis(5-nitrotetrazolato)cobalt(Ⅲ)perchlorate),DACP (tetraamminediazido cobalt (Ⅲ) perchlorate) and tetraamminebis (3,5-dinitro-1,2,4-triazolato-N¹) copper (Ⅱ) were calculated by VLW code. The coefficients of the JWL equation of state were fitted using the calculated isentropic expansion data. The process of explosive-driven flyer plate was simulated by LS-DYNY program. Results show that the calculated results agree well with the experiments,and the deviations is less than 4%.

Abstract:By deduction from explosion mechanical equations of detonation wave interaction at interface,the simplified calculation method of blast vibration acceleration of target head face was put forward in solid medium after charge explosion. Blast experiments in concrete were performed,and the simplified calculation method was verified by the experimental results. The vibration acceleration value measured by the experiment was 1.47×10⁵ m·s^-2,and it was close with the result calculated by the simplified calculation method(1.73×10⁵ m·s^-2). Results show that the accuracy of the simplified calculation method could meet the needs of engineering design,and the a-t curve of the solid medium after blast could be calculated anywhere if the exact detonation wave p-t curve is known.

Abstract:A PSO-BP neural network simulation model was established with particle swarm optimization (PSO) optimizing biases and weights of back-propagation (BP) neural network. By using the PSO-BP neural network,low-pressure burning rate was simulated and calculated. When the important factor changes in a range,for instance HTPB(hydroxyl terminated polybutadiene,28%-32%),AP(ammonium perchlorate,30%-35%,weight-mean diameter 0.06-0.140 mm),GFP(catocene,0%-5%),the burning rate and pressure index of corresponding formulas were calculated and compared to corresponding experimental results. The results show that the calculation errors of the PSO-BP method are less than ±7%.

Abstract:The influence of burning catalysts and main gaseous products of decomposition on the parameters for pressure differential scanning calorimetry(PDSC) characteristics equation of the burning rate have been analyzed. The results show that the pressure factormin the equation is correlated with pressure exponent and the “burning-heat factor” k_u values of RDX-CMDB propellants(R series propellants) are affected by burning catalysts,and a linear correlation or an approximate linear correlation appears in between the relative concentrations of main gaseous products of decomposition and k_u or mvalues. Therefore,It is considered that the equation can represent the correlation between PDSC characteristics and burning rate,besides,it can be also used to describe the effects of burning catalysts and to quantitatively describe the effects of gaseous products on the increase in burning rate and the decrease in pressure factor or pressure exponent. And,the active mechanism of burning catalyst could be also revealed by means of the PDSC characteristics equation.

Abstract:The effects of five new combustion stabilizers with high-melting point,WB,WC,ZrB₂,ZrO₂ and SiC on combustion performances of screw extrusion double-based propellant were investigated. The results show that the WB,WC,ZrB₂ and ZrO₂ make the burning rate of the control formulation enhanced. The catalytic ability of ZrB₂ and ZrO₂ increases with the decrease of their particle size. The ZrO₂ with particle size of 2.07 μm makes the burning rate at 7 MPa of the control formulation increase by 73%. The highest increase in burning rate of various formulations is exhibited at the pressure of about 7 MPa. The WB and ZrB₂ make the pressure plateau of combustion move to higher pressure range. The ZrO₂ with particle size of 2.07 μm makes the pressure exponent of the control formulation decrease from 7 MPa to 13 MPa and pressure plateau widen to 13 MPa. The SiC and WC make the pressure exponent of the control formulation increase and keep lower pressure plateau.

Abstract:The closed bomb test was used to study the amount of adhesiveness combustion residue of single-based gun propellant and triple-based gun propellant under the conditions of different charge density（0.05-0.20 g·cm^-3）,different test pressure(49-105 MPa) and different igniter(black powder and CBI powder) with different ignition charge. The experimental and tested results in firing field were compared. The results show that as the charge density and combustion pressure increase,the combustion residue decrease and that the CBI powder makes adhesiveness combustion residue decrease. The adhesiveness combustion residue of triple-based gun propellant in closed bomb test is 1.6 times greatly than that of single-based gun propellant,and one in firing field is 1.5 times greater than that of single-based gun propellant,showing the experimental results agree with tested results in firing field.

Abstract:The modified single base propellant was prepared by using an impregnated-deterred technology. The erosion of the propellant to barrel was characterized by erosion tube test. The static combustion performances of the propellant were investigated by closed-bomb test. The dynamic interior ballistic performance of the propellant was studied by 857-30 mm gun. The results show that compared with the conventional single propellant,the barrel erosion of the modified single base propellant decreases by 16.4%,the value of progression factor (P_r) increases from 0.035 to 0.445,and the muzzle velocity increases by 9.8% from 856.6 m·s^-1 to 941.3 m·s^-1,revealing that the modified single propellant prepared in this work has the advantages of high combustion progressivity and low erosion.

Abstract:The definition and development of stage fireworks were introduced. The radiation characteristics of flame temperature and sparks temperature of stage fireworks during being displayed were discussed. The thermocouple tree testing apparatus consisting of 59 thermocouples was established to measure the flame temperatures of stage fireworks. The flame temperature distribution of typical stage fireworks was investigated by temperature measure system with thermocouple and infrared thermograph. The results show that the flame temperature of typical stage fireworks is extremely high,and the temperature nearby the exits of the fireworks during being displayed are up to 1200-1450 ℃. There is a long and narrow high temperature region along the emitting direction of the stage fireworks. The size of high temperature region of stage fireworks is positively relative to its basic display performances,such as emitting heights,emitting velocity,radiuses and durations. However,the size of high temperature region of stage fireworks is essentially depend on the compositions,dosage and combustion condition.

Abstract:In order to characterize the intensity of the muzzle flash more accurately,a high speed CCD （charge-coupled device） camera was used to shoot the muzzle flash of gun propellants A and B used in 30 mm gun,and nitramine gun propellant C just-in-time,and the image processing software Image-Pro Plus6.0 was used to edit the photographs of the experiment to get the flash area,the maximum dimension of the flash,the average flash area,the average circumference of the muzzle flash,and the integral optical density (IOD). The flame temperature was calculated by Wien formula. The intensity of the muzzle flash was characterized and analyzed through the comparison of the obtained parameters. The results show that the shape and intensity of the muzzle flash can be characterized by analyzing the parameters obtained. The IOD can be used as a parameter of characterizing the geometer and radiancy of the muzzle flash.

Abstract:In order to study the effects of the star-shaped liner of differently half wedges（15°，25°，35°，45°，55°，67.5°） on jet formation,the LS-DYNA software was used to perform numerical simulation on the process that a structure of the new star-shaped liner forms jet,analyzing the forming process and the effects on forming and jet velocity of the differently half wedges of star shaped liners. Results show that the velocity of second-gathering jet which the star shaped liner forms increases by 33％,compared with the initial jet. The half wedges are suitable for 20°~35°. The penetration performance of jet is better when the number of wedge is 3.

Abstract:The sputtering and etching techniques of Ni-Cr film igniting resistor were studied in order to achieve even resistance and low firing voltage,at the same time,the parameter of igniting resistor was tested. The results show that the velocity of film sputter diminishes and the compact performance of film improves as sputtering power reduces. The resistance coherence of Ni-Cr film igniting resistor is good,and average firing voltage is 6.67 V when charge capacitance is 47 μF.

Abstract:The recent domestic and international studies on tetrazole energetic metal complexes (TEMCs) were classifiedly reviewed. Some synthesis and research trends of the TEMCs were introduced. 5-Cyanotetrazole (CT),5-nitrotetrazolium (NT) and 5-aminotetrazole (AT) are the three most important ligands,which have attracted more and more attention due to their excellent performance and distinctive structure characteristics. Our recommendations are as follows: (1) The synthesis processes of TEMCs have such advantages as less separation steps,mild reaction condition,easy operation,fine controllability,high yield and less pollution. However,the structure and properties studies are still difficult. And the inquiry into the solid-state molar enthalpy of formation has not been reported in the literatures. (2) Altering the central metal ions or the outside cations,changing the number of ligands and modifying preparation methods are all possible ways to search TEMCs that could meet our requirements. (3) Systematic study on the structure and properties of these complexes should be carried out through designing and selecting proper ligands and metal ions,and meanwhile,controlling all the factors such as reaction conditions,which might be of important significance to the experimental study.

Abstract:The preparation,separation and purification of fullerene were introduced. We analyzed the preparation of fullerene by arc discharge,laser/plasma evaporation graphite method,benzene-oxygen flames synthesis,catalytic-pyrolysis of hydrocarbon,and detonation-assisted chemical vapor deposition,and considered the factors affected the preparation were the reacting region temperature,pressure,annealing temperature,catalyst,and protective gas. Comprehensive assessment of these methods shows benzene-oxygen flames synthesis has a remarkable advantage in cost,which is the mainstreaming approach in international commercial process. The difficulty and key factors lie in preparation and purification of fullerene,therefore it is important to find a quick and efficient method of separation and purification.

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