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Abstract:With a new method of the oligomerization of dicyclopentadiene and clopentadiene, a high density hydrocarbon fuel tricyclopentadiene was synthesized with a yield up to 83.2%. The effects of catalyst amount, temperature, solvent on the reaction of TCPD was studied. Results show that the optimum conditions are the molar ratio of n(Ni(PPh₃)₂Cl₂):n(Zn):n(CPD)=0.05:0.6:1, reaction temperature 60 ℃, and reaction time 8 h. With respect to the Diels-Alder method, the oligomerization method has lower reation temperature and pressure (0.1 MPa), and higher yield.

Abstract:Triazidotriacetin (TAA) was synthesized via esterification and azidonation using propanetriol as raw material. The overall yield was 84.1%.The structures of intermediates and target compound were characterized by IR, NMR and elemental analysis. The factors affecting esterification and azidonation reactions were discussed. Results show that the optimum conditions of azidonation reaction are determined as: the dosage of NaN₃ is 1.10 times of theoretical value, i.e. n_exp:n_theo=1.10 (molar ratio), the dosage of water is 5%~25% of the total volume of acetone-water mixed solvent, and the reaction time is 10 h. The yield of TAA is 95.0% and its purity more than 96.8%.

Abstract:3,6-Diamino-1,2,4,5-tetrazine(DAT) was synthesized by nucleophilic substitution using 3,6-bis(3,5-dimethylpyrazol) -1,2,4,5-tetrazine (BT) as the precursor. Then the 3,3′-azobis(6-amino-1,2,4,5-tetrazine) (DAAT) was obtained from oxidative coupling reaction of DAT, and the energetic compound 3,3′-diazenebis(N-(2,2,2-trinitroethyl)-1,2,4,5-tetrazin -6-amino) (BATAT) was first synthesized from 2,2,2-trinitroethanol and DAAT. The structure of BATAT was determined by MS, ¹H NMR and ¹³C NMR. The density, heat of formation, detonation velocity and pressure of BATAT were calculated by Monte-carlo method and Kamlet-Jacobs formula. Results show that the density, detonation velocity and pressure are 1.827 g·cm^-3, 8.76 km·s^-1 and 34.11 GPa, respectively.

Abstract:Diazidoglyoxime was synthesized using solution glyoxal (40% w/w in H₂O) and hydroxylammonium as starting materials through substitution, chloration and nitrine reaction. Its structure was characterized by IR, elemental analysis and NMR. Results show that the impact sensitivity H₅₀ is 17.5 cm, and the friction sensitivity is 36%. Based on the study of effects of the nitrine reaction, the optimal reaction conditions were determined as following: reaction medium is dimethyl formamide, reaction temperature 0 ℃, and the yied of nitrine reaction 81.3%.

Abstract:In order to obtain green and insensitive high energy explosives, 50 grams-scale synthetic method of dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) was investigated. The key intermediate of 5,5′-bistetrazole-1,1′-diol dihydrate (1,1′-BTO) was synthesized through oximation, chlorination, azidation and cyclization from glyoxal. TKX-50 was successfully obtained from the reaction of 1, 1-BTD with hydroxylamine aqueous solution. The product was characterized by ¹H NMR, IR, MS, DSC and element analysis. In the preparation process of TKX-50 from 1,1′-BTO, the influence of molar ratio of reactants, reaction time and temperature on the yield of TKX-50 were studied. The optimal conditions of the process were determined: when the reaction was operated at 80 ℃ for 1h with the molar ratio of n(1,1′-BTO):n(NH₂OH·HCl):n(NaOH) = 1:2.2:2.2. The yield could achieve in 80.1%. The total yield of the synthetic route is 41.5 %. The technology is valuable for the preparation of TKX-50 in large scale.

Abstract:In order to study the burning spectrum of metaldehyde and copper nitrate-ammoniamixture, spectroscopic properties of the mixture were tested by thermogravimetry-differential scanning calorimetry (TG-DDSC) TG/DSC method) and photoelectric detection technology. Based on thermal analysis of the mixture, its thermal decomposition process and possible combustion luminous mechanism were studied, and compared with those tested by the burning spectrum. Results show that the burning flame of metaldehyde is yellow and there is a peak at 591.35 nm which is formed by burning of carbon. When mixed the metaldehyde, thermal decomposition process of copper nitrate-ammonia is changed, with the exothermic peak decreasing from 272.88 ℃ to 254.78 ℃. The green and yellow flame gives off when metaldehyde and copper nitrate-ammonia mixture burns and the spectrum peaks appear separatly at 545.8 nm and 589.33 nm, which is related to carbon burning and forming of copper free radical. The results of theoretical prediction are in agreement with the experimental.

Abstract:Nitrocellulose samples (NC) with A, B, C, and D grade were synthesized by nitrating Canadian softwood in HNO₃/H₂SO₄/H₂O and HNO₃/CH₂Cl₂, respectively. The nitrogen content and nitrogen content distribution (uniformity of nitration) of nitrocellulose were analyzed by a polarizing microscope. Using high-pressure steam explosion technology, soft wood was treated before processing. The effect of steam explosion treatment on the nitrogen content distribution of high nitrogen B and low nitrogen D grade NC was discussed. Results show that the nitrogen content distribution of nitration product from HNO₃/CH₂Cl₂ is more uniform than that of product from HNO₃/H₂SO₄/H₂O under the same nitrogen content condition. Uniformities of nitration indicators of NC of A, B, C and D grade improve by 16.9%、17.5%、16.8% and 25.7%, respectively. Steam explosion preprocess can improve nitrogen content and uniformity of product in the same nitrification system because the efficiency of nitration agents diffusion to cellulose fiber interior is improved by this treatment, and thus the uniformity for B grade NC can increase by 6.06% and for D grade NC by 7.56%.

Abstract:Mn₃O₄ microspheres were successfully prepared by a solvothermal method using manganese (II) acetate tetrahydrate and anhydrous ethanol as raw materials. The effects of reaction temperature and reaction time on experimental results were investigated and discussed. The optimum conditions of reaction at 160 ℃ for 4 h were obtained. The composition and morphology of Mn₃O₄ microspheres were characterized by X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The effect of Mn₃O₄ microspheres on the thermal decomposition of ammonium perchlorate (AP) was investigated by differential scanning calorimeter (DSC). Results show that Mn₃O₄ microspheres are an aggregation of ultrafine Mn₃O₄ particle with high crystallinity and a size of 4-10 nm. In comparison with pure AP, the decomposition peak temperature of AP in Mn₃O₄ microspheres/AP mixture shifts by 160.1 ℃ downwards, and appears at 297.1 ℃, indicating that Mn₃O₄ microspheres have a significant catalytic effect on thermal decomposition of AP.

Abstract:The thermal decomposition of AlH₃, glycidyl azide polymer(GAP) and AlH₃/ GAP mixed system were studied by in-situ thermolysis-fourier transform infrared spectroscopy(FTIR) coupling techniques. Results show that AlH₃ begins to decompose when temperature raises to 100 ℃ and the decomposition rate reaches the maximum at 180 ℃. The azide group of GAP begins to cleavage to imine intermediate at about 200 ℃. The main chain of GAP completely depolymerization is lagging behind. The decomposition process of GAP is changed by AlH₃. AlH₃/GAP system loses mass when temperature raise to 170 ℃, and during the decomposition of AlH₃/GAP, Such unsaturated bonds as C＝N and C＝O are not observed. The possible reason is the strong reduction of AlH₃.

Abstract:The compound 3,6-bis-nitroguanyl-1,2,4,5-tetrazin (DNGTz) was synthesized and its thermal behavior was studied by differential scanning calorimetry (DSC) and thermogravity (TG-DTG). The data in DSC curve were used to analyze the thermal decomposition mechanism and kinetics using the methods of Kissinger, Ozawa and integral. Therefore, the thermal kinetic parameters of the activation energy and pre-exponential factor were obtained as 187.23kJ·mol^-1 and 10^15.01s^-1, respectively. The thermal decomposition mechanism is phase boundary reaction and the differential function is f(α)=1. Then, the thermal safety of DNGTz, the density (ρ=1.762 g·cm^-3) and thermal conductivity (λ= 0.1856 W·m^-1·K^-1) were estimated and the specific heat capacity (c_p) was measured to obtain the equation of c_p with T in a micro-calorimetry (Micro-DSCIII) which is c_p(J·g^-1·K^-1)=-2.8805+2.1283×10^-2T-2.3132×10^-5T²-1.1689×10^-8T³ (287K < T < 352K). Then, the thermal decomposition kinetic parameters, mechanism function and the equation of c_p, ρ and λ were combined to evaluate the adiabatic-time-to-explosion (t_TIad= 8.16 s), the self-accelerating decomposition temperature (T_SADT=249.12 ℃), the thermal ignition temperature (T_be =262.31 ℃) and the critical temperature of thermal explosion (T_bp=277.68 ℃), thermal sensitivity probability density function S(T) vs T for DNGTz (infinite cylindrical, spheroidic or infinite platelike) with the radius of 1m surrounded with 300K, the peak temperature (T_S(T)max), safety degree (SD), critical thermal explosion ambient temperature (T_acr) and thermal explosion probability (P_TE). The thermal safety of the spheroidic sample is found to be better than that of the infinite cylindrical or infinite platelike sample.

Abstract:To understand the thermal decomposition kinetics and thermal safety of hydrazinium nitroformate (HNF), thermal decomposition characteristics of HNF were studied by vacuum stability test(VST), differential scanning calorimetry (DSC) and thermogravimetry (TG). According to peak temperatures of DSC curves and conversion degrees(α) of TG curves at 5, 10, 15 ℃·min^-1 and 20 ℃·min^-1, the apparent activation energy(E_k and E_a) and pre-exponential factor (A_k)for thermal decomposition reaction of HNF were calculated by Kissinger′s method and Ozawa′s method, respectively. The kinetic equations describing the exothermic decomposition process of HNF were presented. Thermodynamic parameters (free energy of activation ΔG^≠, enthalpy of activation ΔH^≠ and entropy of activation ΔS^≠) for thermal decomposition reaction of HNF and thermal safety parameters (critical temperature of thermal explosion T_bpo and self-accelerating decomposition temperature T_SADT) for HNF were calculated. Results show that the volume of gas evolved for HNF is 0.41 mL·g^-1, which does not exceed the standard of 2 mL·g^-1, revealing that HNF has good thermal stability. The exothermic decomposition process of HNF after melting can be divided into two stages. E_k=257.10 kJ·mol^-1, A_k=1.74×10³³ s ^-1, ΔG^≠=103.37 kJ·mol^-1, ΔH^≠=253.82 kJ·mol^-1, ΔS^≠=380.78 J·K^-1·mol^-1 , T_bpo=400.28 K and T_SADT=395.10 K. The kinetic equation of exothermic decomposition reaction may be described as: for the first stage in the α range of 0.20~0.65, $ {\rm{d}}\alpha /{\rm{d}}t = kf\left( \alpha \right) = A{e^{ - \frac{E}{{RT}}}}f\left( \alpha \right) = 5.14 \times {10^{21}} \times \left( {1 - \alpha } \right){{\rm{[}} - {\rm{ln}}\left( {1 - \alpha } \right)]^{\frac{1}{2}}}{\rm{exp}}( - \frac{{1.81 \times {{10}^4}}}{T}) $, and for the second stage in the α range of 0.65~0.80, $ {\rm{d}}\alpha /{\rm{d}}t = kf\left( \alpha \right) = A{e^{ - \frac{E}{{RT}}}}f\left( \alpha \right) = 3.30 \times {10^{14}} \times \left( {1 - \alpha } \right){{\rm{[}} - {\rm{ln}}\left( {1 - \alpha } \right)]^{{\rm{ - }}1}}{\rm{exp}}(\frac{{ - 1.33 \times {{10}^4}}}{T}) $.

Abstract:The molecular geometries and electronic structures of nitro derivatives of symmetric pyrazino-dicycloureas were obtained by a density functional theory (DFT) method with DFT-B3LYP/6-31G^**. Their values of theoretical molecular density (ρ) and heat of formation (HOF) were computed by quantum chemical method. The values of detonation velocity (D) and detonation pressure (p) were estimated using Kamlet-Jacobs equations. Studies on the relationship between structure and property of these nitro derivatives were performed. Results show that the number, positions, surrounding and symmetry of the nitro group within the molecule and the symmetry of the molecular structure are some principal factors affecting the thermal stabilities and detonation properties of nitro derivatives of symmetric pyrazino-dicycloureas. The values of ρ, HOF, D and p for 1,3,5,7-tetranitro-5, 7-dihydrodiimidazo[4,5-b:4'5'-e]pyrazine-2, 6(1H, 3H)-dione are 2.03 g·cm^-3, 265.63kJ·mol^-1, 9.08 km·s^-1, and 39.22 GPa, respectively. The structure of 1,3,5,7-tetranitro-2,6-dioxo-1,2,3,5,6,7-hexahydrodiimidazo[4,5-b:4'5'-e]pyrazine-4-oxide is unstable. These results obtained provide basic research data for molecular design and synthesis of novel high energetic density compounds (HEDC).

Abstract:In order to simulate the loading condition of shell/ insulation / liner/ propellant bonding system in solid rocket motor combustion chambers, a multi-angle tensile clamp was designed for rectangular adhesive specimen according to QJ 2038.1A-2004, and the pure tensile, pure shear and tensile-shear mixed stress on the specimen interface were realized. Results show that the tensile angle (the angle between tensile direction and normal direction of interface) increases from 0° to 90°, and the critical load decreases from 1166 N to 420 N, and the critical maximal principal stress decreases from 0.945 MPa to 0.461 MPa. The critical maximal principal stress ratio of upper interface increases from 1.1 to 2.7 and little change in lower interface, indicating the fracture initiation locations of the specimen are consistent with the calculated.

Abstract:The desensitizing technology of ammonium perchlorate(AP) was studied by coated with wax or themoplastic polyurethane(TPU) as insensitive coating desensitizer. The feasibility study of AP coated by wax and TPU were proved through surface interaction. The coated samples were characterized by using SEM and XPS, and the mechanical sensitivity of AP samples before and after coating was measured and compared. The coupling relations between AP and explosive RDX were studied and the application of coated AP in typical cast PBX was investigated. Results show that AP may be entirely coated by wax and TPU, and the impact and friction sensitivity of AP coated by wax decrease significantly from 100% to 4%, from 100% to 24%, respectively. It indicates that AP is coated more entirely in non-aqueous media(Novec 7200)than in saturated water solution and the coated AP is insensitive which the impact and friction sensitivity fall to 0%. There are strong coupling relations between oxidizer AP and explosive RDX, but it can be reduced or diminished by the desensitizer. The safety of representative cast plastic bonded explosive can be significantly improved by using coated AP instead of uncoated AP, which friction sensitivity decreases significantly from 82% to 0, and the ignition temperature and time-to-explosive in slow cook-off increase 17 ℃ and 14 min, respectively.

Abstract:In order to investigate the effects of fluoroelastomer (F2311) content on the creep performance of TATB-based polymer bonded explosive (PBX), 4 PBX formations modified by adding 0.05, 0.1, 0.2, 0.4 wt% F2311 were prepared, and their three-point bending creep behavior were studied by dynamic mechanical analyzer. Results show that the addition of 0.4% F2311 make the creep resistance performance of TATB-based PBX decrease, and with the decrease of F2311, the creep resistance performance of PBX modified formulation enhances. When F2311 content drcreases to 0.05 wt%, the creep strain of modified formulation is slightly smaller than original formulation at 60 ℃/6 MPa. Meanwhile, six-element model was used to simulate the creep behaviors of PBX. The constitutive equations of creep curves were obtained.The predicted theoretical results coincide quite well with the experimental data. Based on time-temperature superposition principle, the master curves of TATB-based PBX and its modified formulation are obtained at 30 ℃. Results show that compared with original formulation PBX, the long-term creep resistance performance of modified formulation PBX with 0.05 wt% F2311 is enhanced.

Abstract:Using a typical 2,4-dimitroanisole(DNAN) based thermoplastic melt-cast explosive MX-2 the influence of main process factors and important degree of various factors on mean charge density, density difference and ingredient uniformity of the MX-2 were investigated by orthogonal experiments. Results show that the slurry temperature, vacuum pumping time and vacuum are major factors influencing the charge quality. The order of significant influence is: vacuum treatment time > vacuum degree > slurry temperature. The optimal conditions of charge process are as follows: vacuum treatment time 15 min, the vacuum degree -0.090 MPa and the slurry temperature 95 ℃.

Abstract:The radio frequency (RF) sensitivity of semiconductor bridge (SCB) initiator can be improved by negative temperature coefficient (NTC) thermistors and temperature is the key factor for the protection effect. In order to analyze the influence of NTC thermistors on SCB electro-explosive performances at different environment temperature, constant current (1A) was forced to flow through igniters for 300 s at room temperature(25 ℃)and high temperature(70 ℃). Results show that about 59% current of small size SCB (S-SCB) is shunted by NTC thermistor at 25 ℃, and reaching the maximum (63%) at 70 ℃. Furthermore, with capacitor discharge experiment, the electro-explosive performances of the SCB initiators in parallel with NTC thermistors were discussed at above temperatures. Results indicate that burst time and consumption energy of large-SCB(L-SCB) initiators have no significant change at two temperature. But, as for S-SCB, burst time grows from 5.94 μs to 7.18 μs, and consumption energy reduces from 0.388 mJ to 0.178 mJ when temperature ranges from 25 ℃ to 70 ℃.

Abstract:In order to increase the utilization efficiency of laser slapper detonator, it′s necessary to improve and optimize the flyer structure. On the basis structure of flyer, the C/Al/Al₂O₃/Al multi-flyers were prepared by the magnetron sputtering, and the performances of flyers were studied by scanning electron microscope. Taking advantage of photonic dopper velocimetry(PDV), it is found that the accelerating processes of flyers with different parameters are not same, and multi-flyer with the 0.05/0.7/0.7/20.0 μm thickness 1.0 mm diameter reaches a maximum velocity of 2301 m·s^-1.Combined with the analysis of physical properties, the influence of each material used in multi-flyers were discussed. Results show that the velocity of multi-flyer is influenced by reflectivity, vaporization enthalpy and thermal diffusivity of graphite layer, as well as the compactness, ionization energy and thermal conductivity of alumina layer.The accelerating time of multi-flyer is determined by the physical properties of thermal conductivity of graphite layer.

Abstract:By using the magnetron sputtering technology, a Ni-Cr metal film bridge which fit for the insensitive electric initiating explosive device (EED)was made and used to ignite the lead styphnate smearing on the bridge center. The safe current, antistatic property, bridge breaking time and function time were tested and was compared with those of the semiconductor bridge and bridge-belt. Results show that when the resistance is (1±0.1)Ω, the Ni-Cr metal film igniting component has a large safety margin, and its function time and bridge breaking time are between those of two under the same condition of heat dissipation. The igniting time of lead styphnate with the Ni-Cr metal film igniting component is less than 1 ms at the excitation current of 5 A.

Abstract:The firing model was studied to optimal design the bridge-belt electric initiating devices. Based on the non-Fourier heat conduction theory, the electro-thermal energy conversion model was established for the stage from heating to firing. And then the correlation of bridge-belt and input energy was obtained by MATLAB analysis. In order to verify its validity, the critical firing current experiments of Ni-Cr bridge-belts with two sizes were carried out by D-optimal method under the condition of 5 min current input and 50 ms current input. Comparison between the experimental and the analytical demonstrates that the model is reasonable and feasible for designing critical current of Ni-Cr bridge-belt, and the deviation between them is less than 14%.

Abstract:In order to reduce the ignition energy of exploding foil initiator(EFI), and optimize the performance and the parameter of high voltage pulse power source, and the effects of the high voltage pulse power source equivalent parameter on the exploding performance of the foil bridge were investigated with 0.5mm×0.5mm×5.0μm copper foil bridge. By calculating the performance parameter including the equivalent inductance, equivalent resistance, capacitance of pulsed power capacitor and load voltage according to the oscillation waveform parameters from the experimental, the energy efficiency was obtained, and the change rules were studied. Results show that when the capacitance is 0.2 μF, equivalent inductance is 57 nH, the equivalent resistance is 68 mΩ and the load voltage is 2.0 kV of high voltage pulse power source, the exploding performance of the foil bridge is the best, that energy efficiency is 54.8%, reaching the highest, and the time difference of the burst time and the peak time are the shortest.

Abstract:A new charge concept for increasing intelligent ammunition muzzle velocity based on differential traveling charge technology which is able to largely increase gun working volume utilization rate and muzzle velocity within the limits of given projectile overload was proposed. With adaption of sub-caliber sabot projectile design technology, this charge technique facilitates the design of high lift-drag ratio gliding projectile, and increases artillery range. A differential traveling principle interior ballistic numeric model was established. Assuming traveling charge mass 9.2 kg and main principal charge mass 13.41 kg, the calculation of 160 mm gun with the new charge technique demonstrates that the projectile muzzle velocity increases by 26% and gun working volume utilization rate increases by 28%, and under the conditions of maximum bore pressure up to 350 MPa, projectile bottom maximum pressure p_2m≤318 MPa, projectile mass 43.4 kg and travel 7.64 m. Through calculation with modified particle external trajectory model for 130mm sub-caliber gliding projectile, this charge technique can extend maximum range to 99 km.

Abstract:For the loading features of propellant, the mechanical properties were studied by brazilian test. Theories of Hertz elastic contact and elastic mechanics plane stress were applied to analyze the stress distribution law, and the formula was obtained to calculate tensile strength for propellant from Griffith strength criteria. Results show that the initial crack forms at the center region of propellant and propagates along the loading direction, which proves that the Brazilian test is suitable for measuring tensile strength of propellant. The tensile strength of propellant is determined by the load when the splitting happens and the contact width between propellant and indenter. When the storage time extends from 39 years to 47 years, the tensile strength of propellant changes from 13.11 MPa to 12.58 MPa, decreasing by 4%.

Abstract:Grain-molded gun propellant was prepared based on nitramine propellant by surface-deterring, surface-coating, and grain-molding. Two ignition schemes including bottom configuration and central core igniter were designed. Results show that compared with the bottom configuration, ignition delay time shortens 15.2% and the maximum negative pressure difference decreases 8.41 MPa of central core igniter, and the maximum extrusion process of the propellant decreases 11.93 MPa, which indicate that central core igniter ignition scheme can bring perfect ignition performance for grain-molded gun propellant charge.

Abstract:To solve the problem of high impact sensitivity, long preparation technological process and agglomerate of superfine RDX etc. existed during preparation of superfine A5 booster explosive by aqueous suspension coating technology, superfine A5 booster explosive was prepared with the solvent evaporation technology using stearic acid (SA) as insensitive agent, absolute ethyl alcohol as solvent and dispersant. The scanning electron microscope (SEM) observation, impact sensitivity test and SA content determination to samples prepared by two kinds of processes were performed. Results show that the superfine A5 booster explosive is coated more evenly, its particle size is 2.17 ~10.72 μm. Compared with superfine A5 booster explosive obtained by an aqueous suspension coating technology, the characteristic drop height of impact sensitivity of superfine A5 booster explosive obtained by the solvent evaporation technology increases from 18.62 cm to 32.69cm and loss rate of SA decreases from 0.120% to 0.046%, which showing a low sensitive and more exactly component controlling.

Abstract:Based on the minimum free energy method, the energy characteristics of six nitrofurazan compounds, 3-nitrofurazan(NF), 3, 4-dinitrofurazan(DNF), 3-nitrimino-4-nitrofurazan(NNF), 3-nitramino-4-nitrofurazan ammonium salt(ANNF), 3-nitimino-4-nitrofurazan hydrazonium salt(HNNF) and 3-nitramino-4-nitrofurazan hydroxyl ammonium(HANNF), were studied by NASA-CEA software. Effects of the content of nitrofurazan compounds on the energy characteristics of CMDB propellants and effects of pressure on the energy characteristics of nitrofurazan /CMDB propellants were studied. Results show that the specific impulses of HANNF and HNNF monopropellants are 2744.8 N·s·kg^-1 and 2802.2 N·s·kg^-1, respectively, which are obviously higher than that of RDX. Six nitrofurazan compounds make the specific impulse of CMDB propellants increase substantially, in which HNNF and HANNF make the specific impulse of CMDB propellants increase by 74.6 N·s·kg^-1 and 91 N·s·kg^-1 , respectively. The specific impulse for the six propellants increases with the increase of pressure. The order affecting the specific impulse by pressure is DNF>NNF>HANNF>ANNF>HNNF>NF.

Abstract:In order to solve the problems of class 3 permissible explosive for rock roadway excavation in coalmine, such as low explosion energy, short footage and low utilization rate of blast hole, through a large number of laboratory test and plant test, a new explosive composition, the high power class 3 coal mine water gel explosive to improve blasting power was developed, and detected by the authority department. Results show that after 6 months storage, detonation velocity of new explosive is 3600 m·s^-1, power 239 mL, toxic gas composition 20 L·kg^-1, which is better than class 2 coal mine water gel explosive. And its fuel gas safety, sensitiveness, anti-deflagration reach standard of class 3 coal mine water gel explosive. On-site rock roadway test was carried out for study the validation of explosive blasting power from the parameters including the footage, utilization rate of blast hole, hole depth, waste rock fragmentation, thrown distance, around forming and explosive consumption. Results show that under the same conditions and blasting material consumption, the rock breakage capability of new high power class 3 coal mine water gel explosive is near that of the class 2 coal mine water gel explosive, higher than that of class 3 coal mine water gel explosive.

Abstract:By using tetra-butyl titanate as raw material, TiO₂/CNT composite particles were prepared by peptization-reflux method. Morphology of the samples was observed by scanning electron microscope(SEM) and transmission electron microscope(TEM). X-ray Photoelectron Spectroscopy(XPS) analysis show that Ti-O and —OH groups exist on the surfaces of TiO₂/CNT composite particles, and the difference between binding energies of Ti2p_3/2 and Ti2p_1/2 is about 5.7 eV. The photo-catalytic activity of composite particles was studied, and a degradation kinetic model was established by using TNT waste water as target pollutant. Results show that the process of degradation reaction accords with one order reaction kinetics equation. The degradation rate increases with the increase of the initial concentration of TNT in the experimental range, and the kinetic data match well with the L-H model.

Abstract:The chemical oxygen demand(COD) for pure water and nitrobenzene waste water sample containing different content of H₂O₂ was measured and the linear interference of H₂O₂ concentration on COD test was studied. It shows that with increase of the H₂O₂, the COD increases. Without new interference, the ways to suppress interference of H₂O₂ on COD test were discussed including pH value, manganese dioxide catalyst, and catalase. Results show that the catalase eliminates the influence of H₂O₂ on COD determination effectively, and the alkaline environment is in favor of removing the H₂O₂ to some extent, and manganese dioxide catalyst can remove H₂O₂ in short time but it may introduce new interferences. When the reaction time is 3 min, by adjusing initial liquid pH value of 12, adding manganese dioxide catalyst and catalase, respectively, the H₂O₂ removal rate can reach 1.2%, 45.6% and 100%, indicating that catalase can conveniently remove H₂O₂ with unknown concentration, and suppress the interference of H₂O₂ on COD test.

Abstract:Pyrazole and its derivatives are a kind of important nitrogen heterocyclic compounds, and have extensive application in many fields. Based on the reference literatures at home and abroad, this paper summarizes and compares the synthesis methods of 12 kinds of nitropyrazole compounds. Mainly, the research of such pyrazole series of low melting point compounds as 3,4-dinitro pyrazole (DNP) and 1-methyl-3,4,5-trinitropyrazole (MTNP), whose energy is higher than that of 2, 4, 6-trinitortoluence (TNT), and sensitivity is lower than that of TNT, is introduced. It could provide the basis for studying the further synthesis and performance of such energy materials. Their development is prospected, which could provide some new ideas for the further study of explosives with high density, high energy and low sensitivity, and of melt-cast explosive carriers which could take the place of TNT. These three aspects will be the research emphasis for a period in the future: explore the new synthetic route and process optimization of MTNP, study the physicochemical properties and the combination formulations with high energy compounds of the 3,4-DNP and MTNP, seek green nitration agents and catalyst needed in the synthesis of the nitro pyrazole compounds.

Abstract:A novel energetic compound, N, N′-dinitro-N, N′-bis methylenediamine, was synthesized using 3-amino-4-(t-Bu-NNO-azoxy)furazan as starting material. And its structure was characterized by nuclear magnetic resonance (¹H NMR and ¹³C NMR), infrared (IR) spectroscopy, elemental analysis and mass spectrometry, and its backbone was also confirmed by the X-ray structure study of the key intermediate. The detonation performance was calculated by VLW equation of state. Results show density is 1.94 g·cm^-3, detonation velocity 9502.52 m·s^-1, detonation pressure 41.79 GPa and enthalpy of formation 1007.67 kJ·mol^-1, indicating it is a competitive energetic materials.

Abstract:Using 3,3′-dicyanodifurazanyl ether (FOF-2) as starting materials, an excellent energetic plasticizer 3,3′-bis(fluorodinitromethyl) difurazanyl ether (FOF-13) was synthesized via a novel five-step synthetic method, and its structure was characterized by IR, ¹H NMR, ¹³C NMR, ¹⁹F NMR and elemental analysis. The main properties of FOF-13 are followed as: its density is 1.92 g·cm^-3, and melting point 43.5 ℃(DSC), impact sensitivity above 14 J, friction sensitivity 64%, and the mean detonation velocity is 8497 m·s (1.69 g·cm^-1). It shows that FOF-13 is a type of competitive energetic plasticizer.

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