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The heat-resistant energetic compounds with thermal decomposition temperature higher than 300°C reported in the past ten years from the aspects of molecular design, synthesis route and performance evaluation were briefly reviewed. From the perspective of molecular framework, these heat-resistant energetic molecules mainly include monocyclic, fused heterocy-clic, linked heterocyclic and ionic salts. Among them, the fused heterocyclic and linked heterocyclic are the basic characteris¬tics and main directions of the current development of heat-resistant energetic materials. Based on the summary and analysis of the structure and properties of energetic molecules, the construction of large conjugation and hydrogen bonding systems is an effective strategy to improve the thermal stability of molecules. The rational design and layout of conjugated fused heterocyclic and linked heterocyclic skeleton, the introduction of hydrogen bonding system and the further expansion of conjugated structures are expected to realize the construction of ultra-high heat-resistant energetic molecules. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The features of five levitation technologies in normal gravity environment, namely pneumatic levitation, electric levitation, magnetic levitation, optical levitation and acoustic levitation, were summarized and compared. The research progress of combustion of levitated solid fuel particles and liquid fuel droplets in recent yeas were well reviewed. It is pointed out that levitation eliminates the heat conduction between the sample and the carrier during combustion, which is desired to capture the relatively accurate information about the evolution of substances and the release of energy at he microscopic scale, and obtain the intrinsic combustion characteristics of substances. Among the above-mentioned levitation technologies, optical levitation has the advantages of wide application range of substance, precise control of the levitation position of particles/droplets, good levitation stability and easy integration with other diagnostic devices, and is the most promising one in a variety of levitation techniques in the field of combustion of energetic material in future work, it is proposed to strengthen the characterization of the chemical composition of the products of the single-particle/droplet combustion process, expand the research scope of levitation combustion technology in the field of energetic materials, and carry out research on the combustion characteristics and interaction mechanism of multi-particle and multi-droplet energetic materials. 44 References were attached. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To accelerate the research progress of nano-thermite technology in China and grasp the latest development trend and application of nano-thermite technology abroad in time, on the basis of systematically tracking the latest development trends abroad, the preparation and application technology of nano-thermite, the research on the mixture of new nano-thermite and the latest research progress on its reaction performance in the United States, France and other countries were summarized. The preparation technology includes solid phase reaction method, sol-gel method, combustion synthesis method, biosynthesis method and low energy consumption amplification production method. It shows that after 20 years of research, nano-thermite has shifted from laboratory research to preproduction stage. It indicates that the special excellent properties of nano-thermite will make it become the development goal of high-performance energetic materials. The application of nano-thermite in propellant and explosive will make the propellant have higher burning rate, smaller ammunition, more advanced fuel and additive components, and it is expected to be an important way to improve the safety of propellants and explosives, thus meeting the higher requirements for energetic materials in the future. [ABSTRACT FROM AUTHOR]

3D printing technology is applied in the preparation of melt-cast explosives to solve the problems existing in traditional melt-cast explosives, such as more defects, low density, and poor mechanical properties, etc. An independently developed melt-cast explosive 3D printing principle prototype was used to prepare nano-cyclotetramethylenete-tranitramine (HMX)/2,4,6-trinitrotoluene (TNT)-based melt-cast explosives by selecting the melt-cast explosive formulas and adjusting the process parameters. And the microscopic structures, density, uniformity, compressive strength and detonation velocity of two kinds of melt-cast explosives prepared by 3D printing technology and traditional casting technology are characterized and compared. The results show that 3D printing melt-cast explosives have more compacting internal structures with the density of 1.65 g/cm3, the compressive strength of 5.56 MPa, and the detonation velocity of 7 143 m/s. The density, compressive strength and detonation velocity of 3D printing melt-cast explosive are improved by 2.0%; 273% and 2.1%, respectively, compared to the traditionally prepared melt-cast explosive. [ABSTRACT FROM AUTHOR]

The formation mechanism of pore structure of ball propellant with micro-pores made by double emulsion method is revealed. The formation and changing rule of pore structure are studied through sampling, microscopic observation and image analysis during emulsifying, balling and solvent distilling. The results show that the major parameters influencing the shape forming of pore structure are the conditions of emulsion and solvent distillation. The shape and size distribution of dispersed droplets in nitrocellulose emulsion are in basic agreement with the pore structure and pore size distribution in finished ball propellant. As a result, the pore morphology of ball propellant is determined by the emulsification conditions. The conditions of shape forming process have no significant effect on the size and morphology of the pores, while the solvent evaporation conditions have greater influence on the pore size distribution. The faster the solvent is distilled, the worse the pore structure uniformity is due to the agglomeration of pores. The pore structure uniformity of finished particles is improved effectively by reducing the speed of solvent distillation. The pore structure of nitrocellulose ball propellant with micro-pores made by double emulsion method is substantially determined by the morphology of the disperse phase droplets in nitrocellulose emulsion. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of Beijing Institute of Technology is the property of Beijing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

2- ( 3 -nitro-1,2,4-oxadiazole ) imino-5 -nitro-hexahydro-1,3,5 -triazine ( NONHT ) and 2 - ( 3-nitro-1,2,4-oxadiazole) imino -5-nitroso-hexahydro-1,3,5-triazine (NONsHT) were prepared by using n tration of the Mannich condensation product of NOG, tert-butylamine and formaldehyde. All of the compounds were characterized with IR,¹ H NMR, 13C NMR, ESI-MS and elemental analysis. The therma behaviors of NONHT and NONsHT were studied by using multiple heating differential scanning calorimeter ( DSC). Their thermal decomposition kinetic parameters and thermodynamic parameters were calculated by using Kissinger, Ozawa and other methods. The results show that the thermal stability of NONHT is better than that of NONsHT. Their much higher decomposition temperatures than NNHT indicate that the introduction of 3-nitro-1,2,4-oxadiazole ring can improve the thermal stability significantly. [ABSTRACT FROM AUTHOR]

Three new explosives, such as 1-methyl-3 , 5-dinitro-2 , 4-triazole ( DNMT ) , 1-methyl-4 , 5- dinitro-imidazole(4 ,5-MDNI) and 3 ,4-dinitropyrazole ( DNP) , with low melting point were synthesized by using dicyandiamide, N-methy limidazole and pyrazole as raw materials through nitrification reaction, thermal rearrangement and nitrification reaction etc. The technical parameters were optimized to obtain the optimal conditions. The compounds were characterized by melting point testing, IR spectrum, element analyzing and 1HNMR. Furthermore, thermal decomposition performance of these products were analyzed through DSC thermal analyzer, which melting points are MDNT 95 °C ,4,5-MDNI 77 °C , DNP 85 °C . Three explosives exhibit the lower melting points and good thermal stability. [ABSTRACT FROM AUTHOR]

Using the instantaneous detonation assumption and linear approximation of tiny charge mass, the impulse and thrust of a micro-detonation thrust unit operating in vacuum are theoretically calculated. Based on this, the influences of specific detonation heat, isentropic exponent and length of the nozzle on the impulse and the thrust are studied. Furthermore, by numerical simulation, the time-dependence of the pressure on the end of nozzle is obtained, and the variation of impulse provided by the micro-thruster with the length ratio of nozzle to energetic material is also investigated. The results showed that increasing the charge mass, the isentropic exponent and the specific detonation heat can enhance the impulse of a thrust unit, and the nozzle length must be over 4 times of the charge length to achieve the perfect propulsion performance. [ABSTRACT FROM AUTHOR]