含能材料三轴动态压缩实验的一个计算机模拟方法

在含能材料单轴、受限三轴动态压缩实验的基础上，提出一种将计算机数值模拟和实验数据相结合，估算实验系统中钢筒与试件间的库伦摩擦力，从而正确确定含能材料的动态三轴力学性能（弹性模量Ｅ，泊桑比ν，屈服限Ｙ等）的方法。本方法用于ＴＮＴ炸药受限三轴动态压缩实验，通过建立钢筒－试件的库伦摩擦有限元模型，采用ＡＤＩＮＡ通用程序进行动力分析，估算了摩擦力对实验数据的影响，获得了考虑摩擦力修正后的ＴＮＴ三轴动态压缩响应，为含能材料三轴动态力学性能的确定提供了一种有效的方法。     

A Strontium‐ and Chlorine‐Free Pyrotechnic Illuminant of High Color Purity

The development of a red‐light‐emitting pyrotechnic illuminant has garnered interest from the pyrotechnics community owing to potential regulations by the United States Environmental Protection Agency (U.S. EPA) regarding the use of strontium and chlorinated organic materials. To address these environmental regulatory concerns, the development of lithium‐based red‐light‐emitting pyrotechnic compositions of high purity and color quality is described. These formulations do not contain strontium or chlorinated organic materials. Rather, the disclosed formulations are based on a non‐hygroscopic dilithium nitrogen‐rich salt that serves as both oxidizer and red colorant. These formulations are likely to draw interest from the civilian fireworks and military pyrotechnics communities for further development as they both have a vested interest in the development of environmentally conscious formulations.     

Polynitro-Functionalized Dipyrazolo-1,3,5-triazinanes: Energetic Polycyclization toward High Density and Excellent Molecular Stability

A new fused N-heterocyclic framework, dipyrazolo-1,3,5-triazinane, was synthesized and the physiochemical properties of its derivatives were investigated to evaluate the integrated energetic performance. In contrast to 1,3,5-trinitro-1,3,5-triazinane (RDX) featuring a distorted chair confirmation, polynitro-functionalized dipyrazolo-1,3,5-triazinanes have nearly planar backbones, thereby enhancing the density and thermal stability. Among these new energetic tricyclic compounds, 5 a and 12 show favorable crystal densities of 1.937 g cm⁻³ and 1.990 g cm⁻³ at 150 K, respectively, which rank highest in triazinane-based energetic compounds. Additionally, this synthetic approach was carried out to form seven-membered and eight-membered rings, giving rise to tetranitro dipyrazolo-1,3,5-triazepane ( 5 b ) and tetranitro dipyrazolo-1,3,5-triazocane ( 5 c ), respectively.     

冲击作用下凝聚态含能材料热点形成热－机械分析

应用动力有限元方法分析含能材料中热点形成机理。在假定凝聚态含能材料为可压缩的情况下,研究圆形和椭圆形微孔洞附近介质在冲击作用下热－机械响应过程,结果显示冲击波强度、空隙率、微孔洞尺寸和形状、熔点对热点温升有强烈影响,并讨论粘塑性功和固相压缩成为主要机制的条件。     

Investigation of nitrogen‐rich energetic polymers based on alkylbridged bis‐(1‐methyl‐tetrazolylhydrazines)

Nitrogen‐rich energetic polymers were synthesized by the polyaddition reaction of 1,2‐bis(5‐monomethylhydrazinyl‐1H‐tetrazolyl)ethane ( 1a ), 1‐methyl‐1,2‐bis(5‐monomethylhydrazinyl‐1H‐tetrazolyl)ethane ( 1b ), and 1,4‐bis(5‐mono‐methylhydrazinyl‐1H‐tetrazolyl)butane ( 1c ) with hexamethylene diisocyanate. The experiments showed that neither a polymerization from solution or bulk was possible. Therefore, a new method for the polymerization of tetrazolyl hydrazines had to be developed. The formed polymers were characterized by vibrational spectroscopy (IR) and elemental analysis. The energetic properties were investigated by bomb calorimetric measurements along with calculations using the EXPLO5 software. The thermal stability was investigated by DSC measurements. The properties render the polymers into promising compounds regarding an application as energetic binder. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 122–127, 2010     

Energetic properties of nio surface examined by heat-of-adsorption measurement

Heat of adsorption and isotherm of water vapor on NiO samples were measured simultaneously at 301 K to examine the energetic properties of the surface. They revealed that NiO has a relatively uniform surface. The heat of adsorption ranging 80–90 kJ·mol^–1 indicates the production of surface hydroxyl groups on the (100) plane of NiO. It is relatively small compared with that of other metal oxides, which suggests a weak nature of the Ni²⁺ ion sites for chemisorption of water. It is suspected that half of the surface Ni²⁺ ions are covered with hydroxyl groups and the remainings act as relatively strong physisorption sites for water molecules.The authors are grateful for the help of Prof. S. Kittaka of Okayama University of Science in taking electron micrographs. This work was partly supported by Grant-in-Aid for Scientific Research No. 02640348 from the Ministry of Education, Science and Culture of Japanese Government.     

Solar hard X-rays and gamma-rays

We briefly introduce our recent work on the spectral evolution of energetic protons, the beam property of accelerated electrons, the gamma-ray flare classification, the temporal features of the annihilation line, the hard X-ray delayed events, the hydrodynamic process, and the continuum emission in solar flares.     

Ammonia–(Dinitramido)boranes: High‐Energy‐Density Materials

Two ammonia–(dinitramido)boranes were synthesized by the reaction of dinitroamine with ammonia–borane. These compounds are the first reported examples of (dinitramido)boranes. Ammonia–mono(dinitramido)borane is a perfectly oxygen‐balanced high‐energy‐density material (HEDM) composed of an ammonia–BH₂ fuel group and a strongly oxidizing dinitramido ligand. Although it is thermally not stable enough for practical applications, its predicted specific impulse as a solid rocket propellant would be 333 s. Its predicted performance as an explosive matches that of pentaerythtritol tetranitrate (PETN) and significantly exceeds that of trinitrotoluene (TNT). Its structure was established by X‐ray crystallography and vibrational and multinuclear NMR spectroscopy. Additionally, the over‐oxidized ammoniabis(dinitramido)borane was detected by NMR spectroscopy.     

TNT炸药动静态变温三轴压缩力学性能的试验研究

介绍了一种高能材料动静态变温三轴压缩试验装置，在熔点以下温度，通过对国产单质炸药ＴＮＴ在中等应变速率（２－４／ｓ）及准静态（３×１０－３／ｓ）条件下三轴压缩力学性能的测试，得出ＴＮＴ的杨氏模量Ｅ、泊松比ν和屈服极限Ｙ，以及当加载速率和温度改变时这些参数的变化规律。并提出三轴应力状态下屈服极限的一种确定方法。该三轴压缩试验装置以及三轴压缩应力状态下力学参数的测试、分析、处理系统为研究高能材料力学性能提供了一套完整的技术和手段。