Abstract:Refined 3-nitro-1，2，4-triazol-5-one （NTO） product were prepared by spray drying technology to improve the morphology and reduce the particle size. Acetone was used as the experimental solvent. The effects to inlet temperature， inlet flow rate， feed rate and precursor mass concentration on the morphology and particle size of the refined NTO were investigated， and the optimal spray drying process parameters was selected. The surface morphology， molecular structure and thermal stability of refined NTO products were characterized by scanning electron microscopy （SEM）， X-ray diffraction （XRD） and fourier transform infrared spectroscopy （FT-IR）， and synchronous thermal analyzer （TG-DSC）. The results show that the sphere-like NTO with good morphological， stable crystal structure， narrow particle size distribution range and an average particle size of 1.2 μm can be obtained when the inlet temperature is 60 ℃， the inlet gas flow rate is 357 L·h^-1， the feed rate is 3 mL·min^-1， the NTO precursor concentration is 16.57 mg·mL^-1. Compared with the feedstock， the thermal decomposition activation energy of the refined NTO was enhanced by 41.7 kJ·mol^-1， and the thermal explosion critical temperature was increased by 10.4 ℃， which has better thermal stability.

Abstract:In order to obtain super thermite with spherical core-shell structure for 3D printing of energetic materials， Al_2#@CuO and Al_2#@Bi₂O₃ super thermites possessing highly spherical core-shell structure were prepared by spray granulation method for directly coating solid particles. The influence of construction parameters （particle size ratio and solid content） on particle size of super thermite was studied by using NanoMeasure statistical software. The spherical core-shell structure was characterized by scanning electron microscopy and X-ray diffraction. The flowability of super thermite was characterized using the angle of repose method. The ignition characteristics were observed using high-speed cameras. The results show that two types of super thermite possessing highly spherical core-shell structure were prepared using construction parameters of solid content 25%， 2# aluminum powder， and nano metal oxide （CuO， Bi₂O₃） particle size. The structure was an ideal spherical core-shell structure， with an average particle size of about 40 μm. The average thickness of the shell is 7.79 μm （Al_2#@CuO-25%）， 10.47 μm（Al_2#@Bi₂O₃-25%）. Compared with the mechanically mixed sample， the flowability of super thermite with spherical core-shell structure displays a great improvement. The angle of repose of Al/CuO system reduces from 48.8° to 22.9°， and the angle of repose of Al/Bi₂O₃ system decreases from 37.3° to 16.6°. The combustion time of Al_2#@CuO super thermite with spherical core-shell structure increases from 100 ms to about 0.9 s， indicating that microstructure variation has an impact on its combustion characteristics.

Abstract:In order to overcome the problems of easy agglomeration， easy oxidation and poor combustion performance of nano-boron powder， fiuorine rubber（F₂₆₀₂） was used as binder.Nano-boron/F₂₆₀₂ composite microspheres with different process parameterswere prepared by electrostatic spray method.The perparationtechnology of composite microspheres were optimized by orthogonal experiment， and the best preparation conditions for uniform particle size and rounded morphology of microspheres were been found. The morphology， structure and thermal properties of the composite microspheres were characterized by scanning electron microscopy， X-ray diffraction， infrared spectroscopy， and thermogravimetry. The results show that the optimum preparation conditions were as follows： solution concentration 7%， the content of F₂₆₀₂ to boron power 3.5%， the injection rate 1 mL·h^-1 and the injection voltage 18 kV. The prepared nano-boron /F₂₆₀₂ composite microspheres have good dispersion， and the serious agglomeration of nano-boron powder is improved. The boric acid peak on the surface of boron nanoparticles did not appear on the composite microspheres， indicating that the composite microspheres prepared by electrostatic spraying can effectively prevent the surface oxidation of boron nanoparticles. Compared with the raw boron powder， the weight gain of the composite microspheres increased by 22.98%， and the reaction degree with oxygen was deeper， and the boron energy release was more complete.

Abstract:In order to enhance the compatibility of α-AlH₃ with HMX and CL-20， silane coupling agents with different organic functional groups were used to coat α-AlH₃. The structure and morphology of α-AlH₃ were characterized by X-ray diffractometry （XRD）， infrared spectroscopy （FT-IR）， X-ray photoelectron spectroscopy （XPS） and scanning electron microscopy （SEM）， and the compatibility of α-AlH₃ and modified materials with HMX and CL-20 were investigated， respectively. The results showed that the silane coupling agent could form a uniform cladding layer on the surface of α-AlH₃ without changing its native structure. γ-thiopropyl triethoxysilane （KH580） coating improves the thermal stability of α-AlH₃， increases the maximum thermal decomposition temperature by 1.7 ℃ and increases the activation energy E_a value by 2.21 kJ·mol^-1. After the modification of KH550 and KH570 ， the compatibility of α-AlH₃ and HMX hybrid system increased from level 3 to level 1. After the modification of KH550， the compatibility of α-AlH₃ and CL-20 mixed system is increased from level 4 to level 1.

Abstract:In order to evaluate the effect of damp-heat aging on the properties of pentaerythritol acrolein resin （123 resin）-RDX polymer， experimental study on accelerated aging by dampness and heat was carried out. The moisture absorption properties of pouring PBX explosive specimens， mechanical properties before and after moist heat aging， section morphology and aging mechanism were analyzed by means of water adsorption instrument， material testing machine， scanning electron microscope and infrared spectrum. The results showed that the moisture absorption rate of RDX， 123 resins and pouring PBX increases with the increase of relative humidity. Among them 123 resins has the highest moisture absorption rate. Relative to the main explosive RDX has stronger hygroscopic property. The results show that the moisture absorption of pouring PBX is dominated by 123 resins in the system. The results of infrared spectrum showed that 123 resins had hygroscopic hydrolysis after heat and hunmidity aging， Meanwhile， moisture and heat aging significantly affected the mechanical properties of 123 resins-based casting PBX. The mechanical properties of 123 resin based cast PBX decreased significantly with the increase of ambient humidity， and the mechanical properties decreased obviously with the extension of aging time.. After aging at 65 ℃/90% RH for 5 days， the compressive strength decreased by 17.60 MPa（24.09%）， the tensile strength decreased by 2.32 MPa（28.78%）， when aging for 30 days， the compressive strength decreased by 77.80% and the tensile strength decreased by 58.56%； The results showed that 123 resins based casting PBX was sensitive to humidity， and the hydroscopic hydrolysis of 123 resins was the main reason for the significant decrease of the mechanical properties of casting PBX.

Abstract:In order to study the low hygrothermal aging mechanism of Al/Zr/KClO₄ ignition agent， samples were aged at 85， 71， 60 ℃ and 50 ℃ . Thermal analysis， X-ray photoelectron spectroscopy （XPS） and scanning electron microscopy （SEM） X-ray spectroscopy （SEM-EDS） were used to analyze the thermal decomposition performance of Al/Zr/KClO₄ ignition agent and the changes of surface elements and morphology with temperature and time. The results show that some molecules on the surface of KClO₄ crystal are degraded to KClO₃ and KCl with the increase of aging time. The surface of Zr is further oxidized to ZrO₂ under the action of heat， and Al does not change significantly. Meanwhile， the surface morphology of each component did not change. The thermal decomposition activation energy and enthalpy of Al/Zr/KClO₄ ignition agent showed a decreasing trend with the increase of aging time. Compared with the unaged ignition agent， the activation energy decreased by 29.57 kJ·mol^-1 and the enthalpy decreased by 160 J·g^-1 after aging at 85 ℃ for 160 days. The aging mechanism function of ignition agent was obtained by fitting reaction rate， enthalpy value and surface element parameters of each component. It was found that the reaction rate， oxidation of Zr and degradation of KClO₄ could reflect the effect of time and temperature on low hygrothermal aging of ignition agent. The aging mechanism function was N-order reaction， the aging process is the oxidation of Zr and the degradation of KClO₄. The oxidation rate and reaction degree of Zr is greater than the degradation of KClO₄， and the aging activation energy was 95.86-128.90 kJ·mol^-1.

Abstract:Quickly and accurately detect and analyze the intermediates and impurities produced in the synthesis of Hexanitrohexaazaisowurtzitane （CL-20）， is important for controlling the purity or quality of CL-20， and ensuring its sensitivity and detonation performance. In this study， nuclear magnetic resonance （NMR） and ultra-high performance liquid chromatography-Quadrupole time-of-flight mass spectrometry （UHPLC-QTOF-MS） were used to rapidly and efficiently analyze the impurities in the typical synthesis process of CL-20. The results showed that the impurity in HBIW was 1，3-dibenzyl imidazole， the impurity in tetraacetyl dibenzyl hexazepane （TADB） was low acylated triacetyl tribenzyl hexazepane （TATB）， and the impurity in tetraacetyl hexazepane （TAIW） was incomplete TADB. The impurities in CL-20 were not fully nitrated monoacetyl pentanitrohexazazine （MPIW） and diacetyl tetranitrohexazazine （DATN）.

Abstract:To explore the explosion characteristics of propylene oxide mist， a 20 L spherical liquid fuel explosion test system was used to study the effects of ignition delay time and mass concentration on the explosion characteristics of propylene oxide/air mixture. At the same time， high-speed cameras were used to photograph the flame propagation process， the dynamic distribution images of flame temperature field was reconstructed by colorimetric pyrometer technology and the effect of mass concentration of propylene oxide on the flame temperature was discussed. The experimental results showed that with the increase of ignition delay time， the maximum explosion overpressure and the rise rate of maximum overpressure increased first and then decreased， while the combustion duration was on the contrary. The optimal ignition delay time was 100 ms with the maximum explosion overpressure reached 0.89 MPa. With the increase of the mass concentration of propylene oxide，the maximum explosion overpressure， maximum overpressure rise rate and maximum average flame temperature were all initially increased and then decreased. When the mass concentration was 498 g·m^-3， the maximum explosion overpressure and maximum overpressure rise rate were both the highest， which were 1.02 MPa and 60.91 MPa·s^-1， respectively. But the mass concentration corresponding to maximum average flame temperature was significantly lower than that of maximum explosion overpressure. When the mass concentration was 415 g·m^-3， the flame average temperature reached the maximum value of 1937 K. The research results can provide reference for optimization of detonation performance and evaluation of damage efficiency of the fuel air explosive.

Abstract:The cylinder test is one of the most commonly used tests to calibrate the parameters of the equation of state for explosive detonation products. A probe cylinder test platform was designed and established in order to determine the parameters of the JWL equation of state for explosive detonation products. A 20 ns high-resolution pulse chronograph and a set of probes with radial displacement differences were used to record multiple discrete points during the expansion process of the cylinder. When the cylinder expands to the head of the probe to form a circuit loop， the pulse chronometer records the time. Based on this， the displacement-time history curve of the cylinder wall can be obtained. Two probe cylinder tests of TNT explosives were carried out， and discrete points of cylinder expansion displacement were obtained. The experimental results show that the difference between the two sets of test curves is small， indicating that the probe cylinder test has good repeatability. The JWL equation of state parameters of TNT explosive detonation products were determined using the BP-GA algorithm. The determined JWL parameters were then substituted into the finite element software for numerical verification， and the results showed that the determination coefficient R² of the simulation displacement curve was 0.9997， indicating the high accuracy of JWL parameters.

Abstract:Microbial remediation technology refers to the remediation technology that uses artificially domesticated microorganisms with specific functions to degrade harmful pollutants in the contaminated site into harmless substances through their own metabolism in the appropriate environment. In the process of microbial remediation of energetic compounds contaminated sites， improving microbial degradation efficiency and exploring metabolic pathways and intermediate metabolites are key issues. This paper briefly described the pollution status of energetic compounds， introduces common methods for remediation of energetic compounds contaminated sites. The advantages of microbial remediation of energetic compound contaminated sites were focused on， and the common strains， external nutrition sources and practical applications of microbial remediation of energetic compound contaminated sites were summarized. Besides， the intermediate metabolites produced by various energetic compounds in the process of microbial degradation were sorted out， and the metabolic pathways in the degradation process of various energetic compounds were also summarized. The development trend of microorganism application in remediation of energetic compound contaminated sites was prospected. The prerequisite for improving the efficiency of existing microorganisms in degrading energetic compounds is the research of microbial agents with better biological stimulation effect. The analysis of metagenomics， macronenenebb transcriptome， macronenenebc proteomics and metabolomics of microbial strains that degrade energetic compounds should be emphasized as a way to strengthen the research on DNA， RNA， proteins and metabolites， and also to improve the degradation effect through transgene to better stimulate the potential of microbial remediation of energetic compound contaminated sites.

Abstract:The typical energetic compounds represented by 2，4，6-trinitrotoluene （TNT） have multiple toxic effects， which seriously threaten the life and health of of production personnel. In order to comprehensively understand the toxic effects of various typical energetic compounds， TNT， cyclotrimethylene trinitramine （RDX）， cyclotetramethylene tetranitramine （HMX）， hexanitrohexaazaisowoodane （CL-20）， 1，1-diamino-2，2-dinitroethylene （FOX-7）， 2，4-dinitroanisole （DNAN）， 3-nitro-1，2，4-triazol-5-one （NTO）， 1，1''-dihydroxy-5，5''-bitetrazole dihydroxylamine salt （HATO） and ammonium dinitamide （ADN） 9 common typical energy compounds in mammals， and their main toxic effects were reviewed. It was pointed out that TNT has genotoxicity， carcinogenicity， reproductive toxicity and other toxic effects， which can lead to anemia， lens abnormalities， cataracts and other toxic diseases. CL-20 with genetic toxicity， can induce deoxyribonucleic acid （DNA） oxidative damage and mutation. RDX and HMX are neurotoxic substances and can induce neurotoxic symptoms such as epilepsy. NTO， ADN and FOX-7 have strong reproductive toxicity and can damage the male reproductive system. DNAN and HATO have immune system toxicity， can interfere withlymphocyte levels and damage the spleen. At the same time， it is suggested that the toxic mechanism of energetic compounds should be further studied in the future. Strengthen the research of toxic protection technology of energetic compounds， explore the toxic effect of new energetic compounds and the combined toxic effect of multi-energetic compounds.