Abstract:The gas phase molecular structures and crystal structures of 3, 6-diamino-1, 2, 4, 5-tetrazine (DATz), 3, 6-dihydrazino-1, 2, 4, 5-tetrazine (DHT) and 3, 6-diazido-1, 2, 4, 5-tetrazine(DIAT) were full optimized at the GGA-PW91/DNP level with Materials Studio Program. The energy band, density of state (DOS) and part density of state (PDOS) were calculated. The change rule of the thermodynamic functions with temperature were discussed. The results show that the stability of three tetrazine derivatives obtained by the energy band increases in the order DHT < DATz < DIAT. The active site in main reaction of DATz, DHT and DIAT obtained by analysis of DOS, PDOS and Wiberg bond is N atom on tetrazine ring. The crystal vibration analyses infer that their thermodynamic functions(S_m^θ、C_p,m ^θ、H_m^θ and G_m^θ)display a nearly linear correlation with temperature. With the temperature increasing, S_m^θ、C_{p, m}^θ and H_m^θ gradually increase, whereas G_m^θ gradually decrease.

Abstract:A novel energetic material 3, 4-bis-(3′-aminofurazal -4′-yl)-furazan(BATF) was synthesized with yield of 54% using reduction of 3, 4-bis-(3′-aminofurazal-4′-yl)-furoxan (DATF) and DATF was produced by dimerization of 3-aninofurazan-4-carboxchlorid-oxime(AAOF). Its structure was characterized by IR, ¹³C NMR, ¹H NMR, MS and elemental analysis. The split mechanism of BATF was investigated by MS(EI) spectra analysis.The synthetic conditions of reduction were optimized as follows: SnCl₂·2H₂O is reductant in the mixed water solution of HCl and AcOH, n(SnCl₂·2H₂O):n(DATF)is 3:1~4:1, the reaction temperature 75 ℃ and the reaction time 7 h.

Abstract:In order to reduce the manufactur costs of 1-oxide-2, 6-diamino-3, 5-dinitropyrazine(LLM-105), LLM-105 was synthesized using 2, 6-diamino-3, 5-dinitropyrazine(ANPZ) as staring material and high concentration hydrogen peroxide(H₂O₂) solution as oxidizing agent. The effect of 50% and 85% concentration of H₂O₂ on the oxidation reaction of LLM-105 was discussed. Trifluoroacetic acid (TFA) used was reduced 50% compared with the original method. The synthetic technology of LLM-105 oxidation was optimized by an orthogonal test. The optimum processing conditions were determined as: n(ANPZ):n(50%H₂O₂)=1:6, m(ANPZ):V(TFA)=1:5(g:mL), reaction temperature 25~30 ℃ and reaction time 24 h. The yield of LLM-105 is 95% and the purity 98%.Its structure was characterized by IR spectrometry, elemental analysis, NMR spectrometry and MS.

Abstract:Thermal behaviors of 3, 4-dinitrophyrazole (DNP) were investigated by differential scanning calorimetry(DSC) and thermal gravity/differential thermal gravity(TG-DTG). The compatibilities of DNP with some explosive component materials, including 2, 4-dinitroanisole(DNAN), 1, 3, 3-trinitroazetidine (TNAZ), cyclotrimethylene trinitramine(RDX), cyclotetramethylene tetranitramine(HMX), hexanitrohexaazaisowurtzitane(CL-20), ammonium perchlorate(AP), Al and microcrystal wax were discussed by vacuum stability test (VST) and DSC. Results show that thermal decomposition process of DNP can be divided into two stages.The peak temperature of DSC curve for the first stage is 319.8 ℃, which revealing that DNP has superior thermal stability. And the peak temperature of DSC curve for the second stage is 407.2 ℃. The compatibilities of DNP with DNAN, TNAZ, RDX, HMX, Cl-20, AP, Al and microcrystal wax are good. These materials can be used as components in explosives.

Abstract:Bulk (about 40 mm×40 mm×30 mm) single crystal of cyclotrimethylene trinitramine (RDX) were prepared from acetone saturated solution by solvent evaporation techniques. Single crystal was cut by diamond wire cutter along some oriented crystal plane and variable thickness single crystal slices were obtained. The growth-induced dislocation in RDX single crystals was estimated by high-resolution X-ray Triple Axis diffraction (TAXRD) rocking curve (ω-scan), and the full width at half maximum (FWHM) of (210), (200) and (111) planes were 35.35, 45.31 and 77.92 arcsec respectively. It can be concluded that the dislocation density in (111) plane is largest, while (210) crystal plane is least, and the growth of (111) crystal plane is fastest quickest, while (210) crystal plane is slowest.

Abstract:In order to analyze the properties of TATB based polymer bonded explosive(PBX) at high temperature, the mechanical properties were measured at high temperature.The morphology of rapture section was observed by scanning electric microscopy(SEM). Results show that the PBX compressive strength, tensile strength, creep rupture strength and endurance time decrease with temperature increasing, while the Poisson ration keeps constant. The tensile creep failure model of PBX under 70 ℃ at 3 MPa is debonding between explosive crystals and binder, the failure model is facture of the PBX crystals at 50 ℃ and 60 ℃.

Abstract:In order to find a safe and controllable synthetic process of nitrogen trichloride, electrochemical oxidation of ammonium chloride solution and hydrochloric acid was researched. Carbon tetrachloride was added to extract the product in situ prior to electrochemical procedure. The structure of product was characterized by FT-IR and Raman. The main reaction conditions such as temperature and acidity of solution were observed. The optimum reation conditions are current 600 mA, reaction temperature 15 ℃, acidity of solution 2 mol·L^-1. The mass fraction of nitrogen trichloride is 10.1% for 6 h and the current efficiency is about 75%. The mass fraction of product after 7d dropped to 60% of initial value at 25 ℃.

Abstract:Trihydroxyethyl isocyanuricate(THEIC) using as initiator, trifunctionality glycidyl azide polymer(TGAP, M_n=2500~3000) with nitrogen heterocyclic ring structure was synthesized by cationic ring-opening polymerization of epichlorohydrin and azidation with NaN₃. A novel azide binder glycidyl azide-b-(3-azidomethyl-3-methyl oxetane) copolymers(P(GA-b-AMMO)) were synthesized by polymerization of 3-azidomethyl-3-methyloxetane (AMMO), using TGAP as a macromolecular initiator, and its structures were characterized by Flourier transform infrared spectroscopy(FTIR), nuclear magnetic resonance(¹H NMR and ¹³C NMR) and gel permeation chromatograph(GPC). The effect of polymerization temperature and ratio of materials on the polymerization were investigated. The appropriate polymerization conditions were as fllow: n(BF₃·OEt₂)/n(TGAP)/n(AMMO)=1.35/1/12~16, the polymerization temperature was 0-3 ℃. The results show that the polymerization is controllable in this appropriate polymerization conditions. The total yield of polymers are above 80.0%, functionality ≥ 2.70 and M_n (4000~4400) are closed to theoretical value corresponding. The mechanical test indicated that P(GA-b-AMMO) had better mechanical property compared with TGAP homopolymer. The mechanical strength of P(GA-b-AMMO) /IPDI is 2.04 MPa. The elongation could reach 261%(20 ℃), which is about three times as much as TGAP/IPDI.

Abstract:Thermal stabilities of lead styphnate(LS) / nitrocellulose(NC)/ dibasic lead stearate(SQ-2) were studied by Different Scanning Calorimetry(DSC) and Thermogravimetry (TG).The energetic properties of four propellants(ammonium perchlorate(AP) / hydroxy-terminated polybutadiene(HTPB), AP/NC, LS/ NC and LS /SQ-2) were analyzed with thermodynamic calculation method. Thermal decomposition characteristics of three LS/NC propellants with ratio of LS to NC as 5:5, 6:4 and 7:3 and four LS/SQ-2 propellants with ratio of LS to SQ-2 as 4:6, 5:5, 6:4 and 7:3 were researched. Results show that the thermostability of LS decreases by adding NC or SQ-2, and its energy enhances, in which the effect of NC is more obvious, considering that LS and NC can be chosen as the components of propellant used in micro solid rocket motor.

Abstract:The effect of particle/matrix interface debonding on mechanical behavior of HTPB propellant was studied.The three-phase model consists of particles, vacuoles and matrix were given.The constitutive of HTPB propellant was obtained by the algorithms.According to the first law of thermodynamics, the critical strain of debonding was proposed for HTPB propellant.The overall effective modulus of composite solid propellant was determined based on the Mori-Tanaka method.The constitutive relationship of HTPB propellant is proposed for the uniaxial tension.The mechanical behavior of HTPB propellant reinforced by particles characterized with a log normal size distribution was discussed.Results show that the behavior of composite solid propellant is consisted of the initial linear elastic relation and nonlinear constitutive relation with interfacial debonding.With the increase of the vacuole fraction, the dilatation increases, but the effective properties of HTPB propellant decreases.For composite solid propellant, the proposed constitutive relation is easily used in engineering as long as the value of adhesion energy is available.

Abstract:The tensile deformation and fracture behavior of composite solid propellant were observed by in-situ scanning electron microscopy.The obtained microscopy images under different phase were analyzed by Digital Image Correlation Method(DICM).The microscopic deformation field and failure characteristics of composite solid propellants were obtained.The results show that DICM coupling with SEM is a ideal approach to measure and study the failure of propellant on a grain scale and it can provide the experimental evidence for numerical simulation.

Abstract:The influence on the performance of nitramine modified double base propellant with KE(a nitrite) and K₂SO₄ as eliminated-flame additive was investigated.By using burning rate test, differential scanning calorimetry(DSC), rocket engine test and an infrared thermal imaging device, the influence mechanism was discussed.Results show that the KE has the fewer influence on the heat of thermal decomposition and combustion characteristics, and better effect on suppression after burning of propellants than K₂SO₄.In addition, thermal decomposition characteristics of NC/NG and RDX in propellants are affecteded obviously by KE.

Abstract:Alumnium nanoparticles(AlNPs) were synthesized via reduction of aluminium chloride anhydrous by lithium aluminium hydride with the solution-phase chemical reduction method, using polyethylene glycol(PEG) or polyethylene glycol dimethyl ether(NHD) as a dispersion stabilizer and mesitylene as solvent.The granularity, distribution, morphology, size, component, structure and activity of AlNPs were studied by laser particle size analyzer(LPSA), transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(EDS), X-ray diffraction(XRD), Fourier transform infrared spectrum(FT-IR) and thermogravimetry(TG), respectively.Results show that the average particle size of PEG/AlNPs prepared by PEG as a dispersion stabilizer is 67.7 nm.The average particle size of NHD/AlNPs prepared by NHD/AlNPs=1.1/1(mass ratio) is 23.4 nm.AlNPs belong to cubic crystal system, and their surface are coated with dispersion stabilizer.

Abstract:Four modified single-base propellant(SB projpellant) samples with different contents of nitroglycerine(NG) were prepared using D-5/7 SB propellant as base raw material, fixating polyester content and controlling added amount of NG.The effect of NG content on the combustion progressivity of modified single base propellant was studied by FTIR, closed-bomb test and 14.5 mm gun test. Results show that the greater the NG content in modified single base propellant, the greater the permeation depth of NG, the better the combustion progressivity of modified single base propellant and faster the muzzle velocity of modified SB propellant.In comparison with D-5/7 SB propellant, the muzzle velocity of sample E4(12% NG) increases by 82.5 m·s^-1(8.35%).

Abstract:In order to study muzzle smoke aggregates of the large caliber barrel weapon, the visible light transmittance of muzzle smoke in open system were measured, and based on it, an equations was derived to calculate characteristic smoke capacity that is proportional to muzzle smoke aggregates.The method was applied to measure muzzle smoke aggregates of a 130 mm cannon.Results show that the minimum transmittance is 0.9%, and the average transmittance 20.1% during launching process, the special smoke quantity is 1830.

Abstract:In order to study the ignition process of powered initiators and provide theoretical base for the design of powered pyrotechnics, a mathematical model describing the ignition process was founded by numerical simulation method on the basis of thermal ignition theory.The interior temperature distributions nearby the main charge surface in condition of different ignition source temperature were obtained by means of numerical integral.The following results from distribution curves were obtained:when the ignition source temperature is from 2000 K to 3600 K, the ignition distance depart from main charge surface is from 462.8 μm to 112.4 μm.The ignition delayed time shortens from 8222 μs to 264 μs, indicating that the ignition delayed time shortens when the ignition source temperature increases.When the ignition source temperature goes to 2800 K, the trend of ignition delayed time shortening becomes flat.

Abstract:In order to make the properties of emulsion explosive satisfy the requirements of explosive welding, emulsion matrix, foam and carbonate mineral powder were mixed to prepare a kind of emulsion explosive with low detonation velocity.The microstructure, fluxion property and mechanical sensitivity were tested, the effect of charge diameter on detonation velocity was studied, and the explosive welding test on stainless steel-steel plate was tested.Results show that the internal of explosive have interspaces, shapes of particle are irregular, and have a good fluxion property, and the sensitivities of impact and friction are both zero.When the loading density of explosive is 0.81 g·cm^-3, the actual measured brisance is 9.71 mm, and when the charge diameter is 16-50 mm, the detonation velocity is 1754-2439 m·s^-1.The explosive can satisfy the requirements of explosive welding of metal plate.

Abstract:In order to solve the problem of high cost and pollution for treatment of a large quantity of nitric acid in the nitration of 3-nitro-1, 2, 4-triazol-5-one(NTO), the nitration agent(70% nitric acid), which was designed and prepared by the addition of an appropriate amount of industrial nitric acid into waste acids, was used to synthesize NTO from 1, 2, 4-triazol-5-one with an average yield of 82% and purity of 99.9%.The products were characterized by IR, ¹³C NMR, ¹H NMR, MS and elemental analysis etc.The effects of various factors such as temperature and reaction time etc.on the yield of the nitration reaction were studied.It was experimentally found that the conditions of nitration reaction were optimized as:molar ratio of TO/HNO₃ 1/6, nitration temperature 60-65 ℃, reaction time 1 h.the new nitration agent(70% nitric acid)can be reused for ten times and the amount for the addition of nitric acid reduces by 67.6%.

Abstract:Diazodinitrophenol (DDNP) is the nitro derivate of phenol and a good primary explosive. DDNP waste water contains diazo, nitro and other refractory compounds, with strong acid or strong alkali, and high toxicity. The quality analysis of waste-water produced by DDNP shows that it has a high content of nitro compounds. According to the factory practice, a biochemical and physical method together to deal with treatment of DDNP wastewater with white-rot fungi-peat is presented. When incubated, and acclimated white rot funguses are used, DDNP wastewater treatment conditions are: added amount of peat, 5% and 9%, temperature (37± 2) ℃; pH=4.5±0.5; added amount of manganese sulfate, 1 mg·L^-1; time about 7 days. Effluent results reveal that: chroma is almost zero, pH ≈ 6.0 and COD_cr ≈ 120 mg·L^-1, according with the country second emissions standars.

Abstract:Evolution of crystal microstructure under mechanical loading, characterization technology and the change of the macroscopical properties of PBX after being pressed were summarized. The pressure, temperament, quality of crystal and bonders were concluded to analyze the reason resulting to crystal damage. The mechanism of damage′s emerging was discussed, and several kinds of modeling methods were suggested. The damage in crystal could be reduced if changing the manner of pressing, temperament in pressing, the quality of crystal or bonders. Based on manifold method, discrete element method and digital image processing technique, the model of PBX can be constructed with actual microstructures.

Abstract:Combustion characteristics of Mg particles in air, oxygen, carbon monoxide, carbon dioxide and water vapor were summarized. Different combustion products had different influences on second reaction and burning rate. Based on the analysis both of the combustion phenomenon and products, Mg particle experienced a process from surface heterogeneous oxidation to vapor phase combustion. Oxidation layer was formed by surface heterogeneous oxidation during ignition process and by condensation or sintering of products, oxide surface adsorption reaction or a phase separation of Mg-oxygen solution during combustion process. Based on combustion characteristics in different oxidative gases, mathematical models of a Mg particle combustion in oxygen, carbon dioxide and water vapor were introduced. Studies on Mg particles combustion need to focus on reaction mechanism, and model should reflect more physical and chemical information, such as reaction mechanism, chemical kinetics and effects of oxidation layer on combustion process.

Abstract:The composite semiconductor bridge (SCB) electrical-explosive device (EED) with excellent performances of low ignition energy, short ignition time, high security and high energy output in comparison with polycrystalline silicon semiconductor bridge, is a new type ignition product obtained by a reactive materials-semiconductor bridge combination, using a modern microelectronic technology. The research progress, advantages and weaknesses of the composite semiconductor bridge EED were reviewed. In order to increase the ignition energy of SCB to provide a viable basis and reference, the structure features, reactive materials, ignition conditions and output performance of the multi-layer composite film ignition bridge were comparatively analyzed. Considering that the multi-layer composite semiconductor bridge EED is ideal improvement products of polycrystalline silicon SCB, having a wider range of application and prospects.

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