Abstract:To explore the effect of magnetic field on the explosion characteristics of premixed gas and its mechanism， taking ethylene as an example， the influence law of magnetic field on the explosion characteristics of premixed ethylene/air was experimentally studied. The chain reaction process of ethylene explosion was numerically simulated. The influence of magnetic field force on key free radicals was theoretically analyzed. The transient pressure of ethylene explosion was measured by pressure sensors and the flame propagation velocities were measured by explosion velocity apparatus. Results show that under the maximum magnetic field intensity of 3300 Gs， the maximum explosion pressure of 6.5% ethylene decreased by 18.18% and the explosion pressure rise rate reduced by 17.33%. Along the flame propagation direction， the magnetic field firstly promoted and then suppressed the flame propagation speed of ethylene explosion， in which the suppression effect was greater than the promotion effect. The ethylene explosion was simulated by Chemkin-pro software， and the key free radicals in ethylene explosion were obtained. Different types of free radicals have different intensities of magnetization. Force of free radical under magnetic field is proportional to magnetization of free radical. The magnetic field force has a greater impact on free radicals with high magnetization， and no impact on anti-magnetic substances. Different types of free radicals appear stratification phenomenon under magnetic field. The collisions between different types of free radicals were reduced， and the elementary reaction rate was decreased， which suppressed the ethylene explosion.

Abstract:In order to explore the infrared extinction properties of three-dimensional graphene， three-dimensional （3D） graphene powders were prepared by thermochemical deposition method. The morphological and structural characteristics of the three-dimensional graphene powder were confirmed by electron microscopy and X-ray diffractometer， and the dispersion properties were tested by using a comprehensive powder characteristic tester. Then the infrared extinction properties of three-dimensional graphene were tested by using smoke chamber test， and compared with the extinction properties of composite graphite and carbon fiber under the same test conditions. The results show that the infrared extinction performance of three-dimensional graphene is excellent. The average mass extinction coefficients are about 1.32 m²·g^-1 and 1.09 m²·g^-1 in the infrared wavelength range of 3-5 μm and 8-14 μm， respectively. Compared with composite graphite and carbon fiber， the average mass extinction coefficients of 3-5 μm are improved by 57% and 132%， respectively. And the average mass extinction coefficients of 8-14 μm are improved by 35 % and 102 %， respectively. It can be seen that 3D graphene shows better infrared extinction ability.

Abstract:In order to improve the activity of hydrogenolytic debenzylation catalyst and reduce the dosage of noble metal palladium during the synthesis of hexanitrohexaazaisowurtzitane（CL-20）， carbon supports were prepared by ball-milling/carbonization method using sodium gluconate as a raw material. The effects of carbonization temperature， heating rate and additive addition of sodium gluconate on the support structure and the catalytic activity of the corresponding Pd（OH）₂/C catalysts in the hydrogenolytic debenzylation of hexabenzylhexaazaisowurtzitane（HBIW） and tetraacetyldibenzylhexaazaisowutzitane（TADB） were explored. The pore structure， particle morphology， crystal phase structure， chemical composition and surface chemical properties of carbon supports were characterized by nitrogen sorption isotherm measurement（BET）， scanning electron microscope（SEM）， transmission electron microscopy（TEM）， powder X-ray diffraction（XRD）， element analysis and temperature programmed desorption （TPD）. The results show that the optimized carbonization condition of sodium gluconate was calcination at 700 ℃ with a heating rate of 10 ℃·min^-1 in the presence of additive， NaHCO₃， which could adjust the puffing carbonization of sodium gluconate. The received carbon supports have rich hierarchical pore structure and appropriate amount of surface oxygen containing groups， and the corresponding Pd（OH）₂/C catalysts exhibit high activities in the hydrogenolytic debenzylation reaction of HBIW and TADB.

Abstract:High purity 2，4，6-trinitro-5-ethoxy-1，3-phenylenediamine （DATNEB） can be used as an internal standard in high performance liquid chromatography （HPLC） to accurately analyze the purity of TATB synthesized by the chlorine-containing method. To study the synthesis and energetic properties of DATNEB， high purity DATNEB was prepared from picric acid by aminating with 4-amino-1，2，4-triazole （ATA） and then ethylating with triethyl orthoformate. The overall yield was 32.5% and the purity was over 99.8%. The structure of the product was characterized by IR， ¹H NMR， ¹³C NMR， MS and X-ray single crystal diffraction. The mechanisms of amination and ethylation were discussed， the thermal and detonation properties of DATNEB were also studied. The results show that DATNEB crystallizes in a monoclinic system， space group P2₁/c with a=1.21261（7） nm， b=0.89654（4） nm， c=1.12310（6） nm， V=1.17675（11） nm³， Z=4， ρ=1.62 g·cm^-3. DATNEB exhibits an endothermic peak at 193.9 ℃ and exothermic peak at 236.0 ℃， indicating a good thermal stability. It has a detonation velocity of 7.05 km·s^-1 and detonation pressure of 21.14 GPa，which is comparable to TNT， while the sensitivityis much lower than that of TNT and RDX. Therefore， the synthesized high-purity DATNEB can not only be used as an internal standard， but also an auxiliary component of molten-cast explosives.

Abstract:Aiming at the difficulty in purification of metal pentazolates， the separation and purification of metal pentazolates were studied by precipitation method based on the aqueous solution of sodium pentazolate， which was obtained via C—N cleavage reaction of arylpentazole. Results show that the aqueous solution of sodium pentazolate contains a lot of organic acid salts， as well as inorganic salt impurities such as sodium nitrate and sodium chloride. Compared with N₅ anions， the organic acid salts prefer to precipitate with metal ions in aqueous solution， thus affecting the precipitation of metal pentazolates. Cobalt pentazolate was precipitated from the aqueous solution of sodium pentazolate via acidification， removal of organic acid salts by extraction， and then addition of cobalt chloride. The lower the pH value is， the higher the removal efficiency of organic acid salts is and the higher the purity of cobalt pentazolate is. The optimized separation conditions of cobalt pentazolate are as follows： the pH value is 3， and the molar ratio of cobalt chloride to 4-amino-2，6-dimethylphenol （1） is 0.26∶1. The purity of cobalt pentazolate is up to 97.9% after simple recrystallization as shown by ion chromatography. The applicability of this precipitation method to other metal pentazolates was also studied. Results show that it is also suitable for the separation and purification of iron， ferrous and copper pentazolates.

Abstract:（C₆H₁₄N₂）［Na（ClO₄）₃］ is a representative of energetic perovskite compounds. It is necessary to clarify the corresponding thermal decomposition behavior， thermal decomposition mechanism and sensitivity characteristics in order to promote the application in formulations. Thermal decomposition parameters， including heat release amount and decomposition temperatures， were obtained by simultaneous differential scanning calorimetric and thermogravimetric analyses methods. The relevant decomposition mechanism was analyzed by kinetic simulation calculations. The decomposition products and decomposition processes of （C₆H₁₄N₂）［Na（ClO₄）₃］ were explored by DSC/TG-FTIR-MS coupled technique combined with in-situ infrared technology. The parameters of thermal sensitivity， friction sensitivity and impact sensitivity were obtained by national military standard methods. The results show that the heat of decomposition of （C₆H₁₄N₂）［Na（ClO₄）₃］ is 4227 J·g^-1 at the heating rate of 10 ℃·min^-1 and the decomposition temperature reaches 345 ℃， which is higher than that of most active energetic materials， including Hexogen （RDX）， ogen （HMX） and hexanitrohexaazoisowuzane （CL-20）， indicating an outstanding thermal stability. The decomposition products analysis shows that the cubic cage-like skeleton effectively stabilizes the internal organic molecule， resulting in the high thermal stability of （C₆H₁₄N₂）［Na（ClO₄）₃］. In addition， the outgassing amount of （C₆H₁₄N₂）［Na（ClO₄）₃］ heated at 100 ℃ for 48 h is about 0.04 mL·g^-1， and the impact sensitivity and mechanical sensitivity are 32% and 80%， respectively， which are better than RDX and HMX.

Abstract:The particle size and morphology of energetic material crystal have a great influence on its performance. In order to study the relationship between crystal morphology， particle size and thermal decomposition performance of 1，1-diamino-2，2-dinitroethylene （FOX-7） explosive， FOX-7 explosive particles with different morphologies and particle sizes were prepared according to solvent/non-solvent method. Scanning electron microscope （SEM）， X-ray diffractometer （XRD）， differential scanning calorimeter （DSC） and impact sensitivity tester were used to investigate the crystal morphology and particle size， crystal form， thermal decomposition property and safety property of FOX-7 explosives， respectively. The results show that by changing the cooling rate， stirring rate and other process conditions， FOX-7 explosive particles with different morphologies such as sea urchin shape， spherical shape， flower shape and block shape can be obtained. The crystal form of prepared FOX-7 explosive is consistent with that of raw material as α-form. The crystal morphology and particle size of FOX-7 have a great influence on the breaking of intramolecular hydrogen bonds and the destruction of the conjugated system， and the spherical shape is beneficial to increase the thermal decomposition temperature. For the FOX-7 sample with a same shape， the larger the particle size， the better the thermal stability. Among the FOX-7 samples with diameters of tens of microns， the sample with spherical morphology has the best safety performance.

Abstract:Mechanically mixed and electrostatic sprayed RDX/NC/AP/Al composite explosive using nitrocellulost （NC） as binder， ammonium perchlorate （AP） as oxidant， cyclotrimethyltrnitramine （RDX） and nano aluminum powder （Al） as combustion agent were prepared based on zero oxygen balance. The morphology， structure， thermal properties， combustion process and mechanical sensitivity of the different samples were analyzed by the scanning electron microscopy （SEM）， the Fourier transform infrared spectroscopy（FT-IR）， thermogravimetric differential scanning calorimeter （TG-DSC）， mechanical sensitivity and high-speed photography. The component（NC， RDX， AP and Al） in RDX/NC/AP/Al composite explosives obtained by both method are physical composite. However， the microstructure of mechanically mixed RDX/NC/AP/Al demonstrated in spheres and the electrostatic sprayed samples are microspheres. The mass loss process of RDX/NC/AP/Al composite explosive obtained by two methods contained two stages （200-210 ℃ and 250-350 ℃）. The first stage is the decomposition of part of RDX and AP， while the second stage is the decomposition of the remaining RDX and NC. Compared with the mechanical mixed samples， the activation energy and the critical temperature of thermal explosion of electrostatic sprayed RDX/NC/AP/Al increased by 41.25 kJ·mol^-1 and 4.09 K， respectively. Besides， the mechanical sensitivity is reduced， and the combustion rate is also improved.

Abstract:The safety performance and initiation process of explosives are closely related to their high-temperature and high-pressure behavior. Therefore， it is of great significance to study explosives under high-temperature and high-pressure thus understanding their safety and initiation performance in depth. The structural evolution of twelve explosives under high-temperature and high-pressure is reviewed， including common nitroamine-based explosives represented by RDX and HMX， common nitroester-based explosives represented by PETN，nitro-based explosives represented by TNT， and new high-energy and low-sensitivity explosives represented by LLM-105 and TKX-50. The phase transformation processes of these explosives under high-temperature and high-pressure are summarized in detail， and the similarities and differences of the research results from different research teams on the same material are compared. This review provides a strong basis for the studies of structural evolution of explosives under high-temperature and high-pressure.

Abstract:1²，1⁴，1⁶，3⁴，3⁶，5²，5⁴，5⁶，7⁴，7⁶-decanitro-2，4，6，8-tetraoxa-1，3，5，7（1，3）-tetrabenzenacyclooctaphane-1⁵，5⁵-diol （ZXC-51） was obtained from phloroglucinol and 1，3-difluorobenzene through nitration and cyclization. A series of calixarene energetic salts were received by the reaction between ZXC-51 and different organic base. The single crystal structures of compound ZXC-51 and its four salts were proved by X-ray single crystal diffraction analysis. And the structures of these compounds were also characterized by NMR and elemental analysis. Meanwhile their thermal properties were also analyzed by differential scanning calorimetry. The detonation and safety performance of ZXC-51 were studied. The results show that its theoretical detonation velocity and detonation pressure are 8193 m·s^-1 and 31.18 GPa respectively. And its impact sensitivity is 36 J and the friction sensitivity is more than 360 N.

Abstract:In order to achieve the safety of the preparation process of ultrafine zirconium （Zr） powder， a method for preparing core-shell Zr powder by continuous flow at microscale was studied. A continuous microfluidic system consisting of microfluidic unit and spray-drying unit was established to verify the feasibility. The system can realize the microscale mixing of components， the formation of core-shell structure and the post-processing of samples continuously. Using Zr powder and nitrocellulose （NC） as composite components， the structure regulation of Zr@NC was studied by controlling content of NC and adjusting dry gas pressure at the microscale. In addition， the activity and safety of Zr@NC were analyzed by thermal analysis and electrostatic spark sensitivity test. The results show that the Zr powder with uniform morphology and core-shell structure can be prepared by the continuous microfluidic system. Thermal analysis results show that the oxidation weight gain of Zr@NC is only 1.04% lower than that of the raw Zr， and the energy release is faster. According to the electrostatic spark sensitivity test， it was found that the 50% ignition energy of Zr@NC is increased from 1.42 mJ to 197.82 mJ compared with the raw Zr， which means the electrostatic spark sensitivity is greatly reduced.

Abstract:To improve the yield and purity of 2，6-dimethyl-4-hydroxyphenylpentazole， the preparation method of 2，6-dimethyl-4-hydroxyphenylpentazole （DMAPH） crystal， the raw material of arylpentazole， was investigated through three steps including nitrification， reduction and salification from 2，6-dimethylphenol （DMP）. The structure， crystal morphology and stability were characterized with infrared spectroscopy （IR）， single crystal X-ray diffraction （SCXRD）， scanning electron microscopy （SEM）， powder X-ray diffraction （PXRD）， differential scanning calorimetry （DSC） and theoretical calculation. The results reveal that the yield of 2，6-dimethyl-4-nitrosophenol is up to 90% in the presence of glacial acetic acid and sodium nitrite. The different shapes of DMAPH crystal including sheet， needle， block and plate morphology can be obtained by changing the solvent， while the temperature only affect the particle size of precipitated crystals. The （400） face is the main crystal face of DMAPH crystal from methanol， while in other solvents it is the （214） face. The DMAPH crystals exhibit good thermal stability with decomposition peak temperature ranging from 220-240 ℃. In contrast to amorphous DMAPH powders， the crystalline DMAPH solids have better stability in air， and are more suitable for long-term storage.

Abstract:In order to improve the economic benefit of producing 2，2，4-trimethyl-1，3-pentanediol（TMDP）， a more efficient and safe microchannel continuous flow process was selected to replace the traditional kettle-type batch production method with using isobutyl aldehyde as raw material and sodium hydroxide solution as catalyst. The effects of catalyst sodium hydroxide concentration， dosage， temperature and residence time on the reaction were investigated. The optimum conditions were determined as follows： sodium hydroxide concentration 50%， v（isobutyral）∶v（NaOH）=1， residence time 10 min， reaction temperature 40 ℃. Under these conditions， the conversion of isobutyraldehyde was 99.02%， the selectivity of TMDP was 93.57%， and the yield was 92.65%. The process made full use of the excellent mass and heat transfer characteristics of the microchannel reactor， greatly shortened the reaction time， increased the reaction rate， extended the selection range of process conditions， and realized the effective control of the reaction process of hydroxylaldehyde condensation. At the same time， the kinetic studies were carried out at different temperatures and concentrations of sodium hydroxide， and the kinetic equations and corresponding parameters were obtained with the concentration of sodium hydroxide being 50% and 45% respectively. The macroscopic kinetics obtained by fitting is second-order， and the activation energy and pre-exponential factors are： 26.34 kJ·mol^-1， 2888.26 L·K^-1·mol^-1·min^-1.

Abstract:The refined 3，3′-diamino-4，4′-azoxyfurazan （DAAF） was prepared by surfactant assisted spraying crystallization to improve its safety and initiation performance. Dimethyl sulfoxide （DMSO） and ionized water were separately used as the solvent and antisolvent. The effects of the type and concentration of surfactants as well as the volume ratio of solvent to antisolvent on the morphology， particle size and dispersion of refined DAAF were discussed. The morphology and crystal structure of the prepared refined DAAF were characterized by field emission scanning electron microscope （FE-SEM） and X-ray diffraction （XRD）. The results show that the spherical-like DAAF with uniform particle size distribution （180-220 nm） and good dispersion can be obtained when PEG-400 with a concentration of 0.8 g·L^-1 is used as surfactant and the volume ratio of solvent to antisolvent is 1∶20. Compared with the raw material， the thermal decomposition activation energy of the refined DAAF is increased by 23.1 kJ·mol^-1， the impulse initiation current is significantly decreased to 2.1 kA， and the vacuum venting， electrostatic spark sensitivity and thermal sensitivity are all reduced， demonstrating that the refined DAAF exhibits improved thermal stability， safety and initiation performance.

Abstract:In order to improve the synthesis performance of 3，3′-diamino-4，4′-azoxyfurazan （DAAF） by conventional methods， broaden the synthetic pathway of DAAF. A microfluidic reaction system was designed to synthesize DAAF using 3，4-diaminofurazan （DAF） as the main raw material by microfluidic technology. Orthogonal experiment was designed to optimize the synthesis conditions. DAAF with a purity of 99.33% and a yield of 89.96% was synthesized at 25 ℃， a flow rate of 4 mL·min^-1 and a length of 5 m in the outlet crystallizer. The structure of the synthesized product was characterized by infrared， nuclear magnetic and elemental analysis， and was characterized by scanning electron microscope （SEM）， X-ray diffraction （XRD）， thermal analyzer （DSC/TG） and mechanical sensitivity. The results show that DAAF was clustered flower ball with an average particle size of 5.36 µm； Microfluidic synthesis has no effect on the crystal structure of DAAF. At the heating rate of 10 ℃·min^-1， the thermal decomposition peak temperature is 262.36 ℃， and the mass loss rate during thermal decomposition is 82.79%. The mechanical sensitivity test shows that the impact sensitivity is 90 J， and the friction sensitivity is 0%. Compared with the DAAF synthesized by the conventional method， the average particle size decreased by 7.36 µm， the particle size distribution is uniform and the particle size distribution range is narrowed， the crystal structure does not change， the thermal decomposition peak temperature was advanced by 9.57 ℃， the mass loss rate was reduced by 6.99%， the impact sensitivity is increased by 5 J， and the safety performance is improved.

Abstract:As a new initiation technology， laser initiation can effectively solve the safety problems existing in traditional initiation methods， such as stray current interference. As the energy output carrier in laser initiation sequence， the laser-sensitive primary explosive is an important part of the laser initiation system. At present， complex laser-sensitive primary explosive has becomes a research hotspot. The synthesis of energetic complexes with chain nitrogenous compounds， triazole， tetrazole， and tetrazine as ligands and the development status of laser initiation properties were summarized. The advantages and existing problems of various agents were analyzed， some laser initiation mechanisms were summarized， and the development of new laser-sensitive primary explosives in the future was prospected. It is pointed out that the development of new nitrogen-rich ligands is still an important direction for the future research of laser sensitive energetic complex primary explosives.

Abstract:To explore organic amine oxyanions with simple synthesis procedure and high energy， ethylenediamine diiodic acid and ethylenediamine hexamiodic acid were synthesized with iodic acid and ethylenediamine. The structures were characterized by single crystal X-ray diffraction， powder X-ray diffraction （PXRD） and Fourier transform infrared spectroscopy （FT-IR）. Differential scanning calorimetry（DSC）and thermogravimetric analyzer（TG）were used to study the thermal decomposition process. The power test of lead plate as main charge in 8^# industrial detonator and the burning test were carried out. The results show that two ethylenediamineIodate salts are successfully prepared. The ethylenediamine diiodic acid belongs to orthorhombic system， Pbca space group， cell parameters： a=7.4427 Å， b=6.7418 Å， c=18.2884 Å， Z=8， F（000）=760， D_c=2.982 g·cm^-3， and the peak temperature of thermal decomposition is 185.18 ℃. The ethylenediamine hexamiodate is a cocrystallization of ethylenediamine diiodate and iodate acid. It belongs to monoclinic system， P2₁/c space group， cell parameters： a=7.2350 Å， b=18.498 Å， c=7.5494Å， β=107.947°，Z=4， F（000）=996， D_c=3.840 g·cm^-3， and the peak temperature of thermal decomposition is 179.48 ℃ and 356.87 ℃. The 5 mm lead plate can not be made through when the ethylenediamine hexamiodic acid is used as main charge， while the opposite result occurs when mixed with 10% aluminum powder. The ethylenediamine diiodate can be used as a simple purple smoke agent.

Abstract:［1，2，5］ oxadiazole ［3，4-b］ pyrazine-5，6-（1H，3H）-dione（1） was synthesized directly from 3，4-diaminofurazan and oxalic acid by one-step amide condensation reaction， and the corresponding ionic salts 2-5 were further synthesized by reaction with base. The structures of compounds 1-5 were characterized by infrared spectrum （IR）， 1H and 13C nuclear magnetic resonance（NMR）. The structures of compounds 1 and 5 were further characterized by X-ray single crystal diffraction. The thermal behaviors of compounds 1-5 were investigated based on differential scanning calorimetry （DSC） measurement. The thermal decomposition temperatures of compounds 1-5 ranged from 210.5 ℃ to 313.5 ℃. The physicochemical properties and detonation performances of compounds 1-5 were estimated by Gaussian 09 program and Explo 5（v. 6.01）. The calculated detonation velocities of compounds 1-5 ranged from 7327 m·s^-1 to 8555 m·s^-1， and the detonation pressures ranged from 20.5 GPa to 30.6 GPa. The impact and friction sensitivities were determined by using BAM technology. The impact sensitivity of compound 1 is 27 J and the friction sensitivity is 280 N. The impact sensitivities of compounds 2-4 are all greater than 40 J and the friction sensitivities of 2-4 are 360 N. The impact sensitivity of sodium salt is 7 J and the friction sensitivity is 120 N. Among them， energetic salts 3 and 4 are expected to be new energetic materials with high energy and low sensitivity.

Abstract:To investigate the thermal hazards of the synthetic reaction process of FOX-7， the heat flow curve of the hydrolysisinvolved therein has been measured by using Reaction Calorimeter （RC1）. The n^th-order kinetic models were applied to different temperature systems and the apparent kinetic parameters of these processes were obtained. The results indicated that the exothermic heat of the synthesis reaction was -46.563 kJ∙mol^-1， and the adiabatic temperature rise was 9.1 K. Under the thermal runaway chemical reaction condition， the maximum temperature of the synthesis reaction （MTSR） is 29.1 ℃. The reaction order is 1.21 for synthesis of 2-（dinitromethylene）-5，5-dinitrodihydropyrimidine-4，6-dione. The activation energy （E_a） of the reaction is 73.2 kJ∙mol^-1， with the pre-exponential factor of 5.03×10⁹ s^-1.

Abstract:A novel energetic non-metallic pentazolate salt， 3，5-diamino-4-nitro-1H-pyrazol-2-ium pentazolate （3）， was synthesized by a metathesis reaction of 3，5-diamino-4-nitropyrazole hydrochloride with sodium pentazolate. The structure of 3 was characterized by nuclear magnetic resonance （NMR）， single crystal X-ray diffraction analysis （SC-XRD）， Fourier infrared spectroscopy （IR） and elemental analysis （EA）. The study on thermal behavior of 3 by using differential scanning calorimetry （DSC） and thermogravimetry （TG） show that its onset decomposition temperature is 119.5 ℃， which is higher than most non-metallic pentazolate salts. The apparent activation energies were calculated based on DSC curves at different heating rates. Based on the measured density at room temperature （1.71 g·cm^-3） and calculated enthalpy of formation （503.3 kJ·mol^-1）， the detonation performances of 3 （D=8483 m·s^-1， p=26.4 GPa） were calculated by Explo5 V6.05.02 software. The impact sensitivity and friction sensitivity of 3 are 10 J and 216 N， respectively.

Abstract:Energy Coordination Compound （ECC） has become one of the research hotspots in recent years because of its diverse Coordination modes between different metal elements and ligands， and it is expected to obtain energetic materials with highly adjustable properties. In this paper， the ways and types of assembling ECC with different ligands are reviewed， and the applications of ECC and its functional materials as initiators， propellant catalysts， flammable agents and oxidants of thermite， pyrotechnics colorants are reviewed. Studies have shown that the energetic complexes formed after the coordination of different metal ions and nitrogen-rich ligands show great potential in the field of new energetic materials， and can meet the requirements of energy， sensitivity and other properties through the change of the type and number of ligands. The law of ECC synthesis is summarized and how to improve the energy characteristics and expand the application in the future is prospected.

Abstract:In order to decrease the acidity of insensitive explosive 3-nitro-1，2，4-triazol-5-one （NTO）， NTO·（3，5-DATr） energetic ionic salt （Ⅰ） and NTO/IMZ energetic co-crystal （Ⅱ） were prepared by the reactions of NTO with 3，5-diamino-1，2，4-triazole （3，5-DATr） and imidazole（IMZ）. The single crystals were obtained by solvent volatilization， and the crystal structures were measured by single crystal X-ray diffraction. Crystal Ⅰ belongs to monoclinic crystal system， space group P2₁/c， with M_r=229.19，a=3.5687（7） Å，b=17.245（3） Å，c=14.655（3） Å，β=93.79（3）°，V=899.9（3） ų，Z=4，D_c=1.692 g·cm^-3；Crystal Ⅱ belongs to orthorhombic crystal system，space group Pbcn，with M_r=207.17，a=16.9398（16） Å，b=5.6802（5） Å，c=17.9111（19） Å， V=1723.4（3） ų， Z=8， D_c=1.597 g·cm^-3. Differential scanning calorimetry （DSC） and thermal weight loss method （TG） were used to test their thermal decomposition properties， and the results show that both Ⅰ and Ⅱ have good thermal stability. The Gaussian 09 program was used to optimize the molecular structures and calculate their enthalpy of formation. Software EXPLO 5 was used to calculate the detonation velocity and pressure of Ⅰ（D=7662.3 m·s^-1，p=21.0 GPa） and Ⅱ（D=6490.2 m·s^-1，p=14.6 GPa）. The mechanical sensitivity was tested by the BAM method. Results show that both of them are insensitive towards impact and friction （IS > 40 J， FS > 360 N）. The pH value of standard samples were measured by pH meter. The pH values of NTO， Ⅰ， and Ⅱ in 0.01 mol·L^-1 standard solution are 2.92 （22.8 ℃）， 4.10 （22.7 ℃）， and 4.98 （22.8 ℃）， respectively， indicating that the formation of salt and co-crystal significantly decrease the acidity of NTO.

Abstract:A cyclo-pentazolate anion-based energetic cocrystal （NH₃OH⁺N₅^-）₂·NH₃OH⁺Cl^-·H₂O was designed and synthesized by AgN₅ （or NH₃OH⁺N₅^-） and hydroxylamine hydrochloride（NH₃OH⁺Cl^-） as raw materials. The structure of the compound was characterized by X-ray single crystal diffraction， infrared spectroscopy and elemental analysis. The structure belongs to the monoclinic crystal system，the P2₁/n space group， a=3.8390（6）Å， b=14.665（2）Å， c=21.975（3）Å， V=1236.4（3）ų， α=γ=90°， β=92.034（3）°， Z=1， D_c=1.589 g·cm^-3. In addition， the thermal stability of （NH₃OH⁺N₅^-）₂·NH₃OH⁺Cl^-·H₂O was studied using DSC and TG， and the results showed that its initial decomposition temperature was about 95.6 ℃. Its detonation velocity and detonation pressure were calculated by EXPLO5 to be 8260 m·s^-1 and 23.79 GPa. （NH₃OH⁺N₅^-）₂·NH₃OH⁺Cl^-·H₂O has low impact and friction sensitivities （IS>40 J； FS>360 N）， as the cocrystal of hydroxylamine hydrochloride can greatly reduce the mechanical sensitivity of NH₃OH⁺N₅^-.

Abstract:Herein， two energetic salts， 3，4-diamino-5-（3，4-diamino-1，2，4-triazol-5-yl）-1，2，4-triazolium perchlorate （2） and 3，4-diamino-5-（3，4-diamino-1，2，4-triazole-5-yl）-1，2，4-triazolium nitrate （3）， were prepared by neutralization reaction of 3，4-diamino-5-（3，4-diamino-1，2，4-triazol-5-yl）-1，2，4-triazole （1） with perchloric acid and nitric acid， respectively. The suitable single crystals of 2 and 3 were obtained and the crystal structures were measured by single crystal X-ray diffraction analysis. In the crystal structure of 2， each cation interacted with 12 adjacent perchlorates anions through hydrogen bonding. Layer structures were formed by the cations of protonated 1. Perchlorate anions were embedded into two nearby layers. In the crystal structure of 3， each cation interacted with 10 nearby nitrates through hydrogen bonding. Layer structures were built by the cations and nitrates. The thermal stabilities of 2 and 3 were measured by differential scanning calorimeter （DSC） and thermogravimetric analyzer （TG）. Compounds 2 and 3 had ultra-high thermal stabilities， and their thermal decomposition temperatures were 338.3 ℃ and 289.8 ℃， respectively. In addition， the calculated detonation velocity and specific impulse of 2 were 8308 m·s^-1 and 250.3 s， respectively， indicating 3 shows excellent energetic properties. Compound 3 had excellent mechanical sensitivity. The values of impact sensitivity and friction sensitivity were higher than 20 J and 360 N， respectively.

Abstract:In order to acquire the mechanical properties and constitutive relations of Zr-based amorphous reactive material under dynamic loading， the specimens were made by pressure infiltration casting， and the dynamic compression experiments under loading with different stain rates were conducted with the split Hopkinson bar （SHPB） test system. The stress-strain curves were acquired under different strain rates of 300-1600 s^-1， and a high-speed camera was used to record the fracture and energy output process of the specimens under different strain rates. Results show that the Zr-based amorphous reactive material belongs to brittle materials that no yielding stage exists in stress-strain curves. With the increase of strain rates from 947 s^-1 to 1587 s^-1， the compressive strength of materials increases from 2.71 GPa to 2.78 GPa with a small increase of 2.6%， while the fracture strain decreases from 0.032 to 0.028 with a decrease of 12.5%. The degree of fracture and reaction of the specimen is more evident with higher strain rate and the strain softening phenomenon occurred during the fracture of materials. According to experimental data， a one-dimensional elasto-brittle constitutive model with damage was fitted for the Zr-based amorphous reactive material before the fracture failure of specimens.