氟偕二硝基甲基类含能化合物的合成及性能研究进展

将氟偕二硝基甲基引入至含能化合物分子中,不但可以提高含能化合物的氧平衡、密度和爆轰性能,还可能提高化合物的热稳定性、降低机械感度。构建含氟偕二硝基甲基基团的含能化合物成为新型高能低感含能材料领域的研究热点。通过对近20年来含有氟偕二硝基甲基的含能化合物综述,总结氟偕二硝基甲基类含能化合物的合成方法,分析比较这类化合物的分子结构、理化性质和爆轰性能,为新颖氟偕二硝基甲基化合物的分子设计、合成研究提供参考。     

新型含能化合物1-甲基-35-二硝基吡唑-4-硝酸酯的合成与表征

为了寻求性能优良的含能化合物,以4-氯吡唑为原料,经硝硫混酸硝化、硝酸根亲核取代、碘甲烷甲基化,获得一种新型的含能化合物1-甲基-3,5-二硝基吡唑-4-硝酸酯,并采用红外光谱、核磁共振、元素分析对产物结构进行了表征。实验考察了甲基化过程中反应时间及碘甲烷用量对反应产率的影响,得到较佳的合成条件：反应时间为10 h,碘甲烷用量为3,5-二硝基吡唑-4-硝酸酯用量的2倍,在此条件下产率为55.2%. 计算了1-甲基-3,5-二硝基吡唑-4-硝酸酯爆轰性能,并与其他常用含能化合物进行了比较,结果表明其爆轰性能略低于1,3,3-三硝基氮杂环丁烷而优于TNT. 撞击实验表明,1-甲基-3,5-二硝基吡唑-4-硝酸酯的撞击感度高于TNT及1,3,3-三硝基氮杂环丁烷,与黑索今相近。     

双阳离子型咪唑含能盐的合成及性能

以2?甲基咪唑为原料,二溴甲烷为桥联试剂,经过亚甲基桥联、季铵化、硝化反应得到了双阳离子含能化合物3,3′?亚甲基双(2?甲基?1?硝酰氧乙基咪唑)二硝酸盐,然后通过复分解反应得到一系列分别以苦味酸负离子、二硝酰胺负离子、3,5?二硝基?1,2,4?三氮唑负离子和5?硝基四唑负离子为阴离子的双阳离子型含能盐。所合成的含能盐经紫外可见光谱(UV?Vis)、红外光谱(IR)、质谱(MS)、核磁共振(NMR)、元素分析和热重分析(TGA)等分析表征。采用Kamlet?Jacobs方程估算了所合成双阳离子含能盐的爆速和爆压等爆轰参数。结果表明,双阳离子含能盐具有良好的热稳定性,其分解温度均高于169℃,第一阶段的热分解峰值温度均接近200℃。除了5?硝基四唑双阳离子盐,其余双阳离子含能盐均较对应单阳离子咪唑含能盐具有更高的热分解温度;同时所有双阳离子含能盐较对应单阳离子含能盐具有更高的熔点;部分双阳离子咪唑含能盐较对应单阳离子含能盐具有更高的密度。3,3′?亚甲基双(2?甲基?1?硝酰氧乙基咪唑)二(3,5?二硝基?1,2,4?三唑)盐和3,3′?亚甲基双(2?甲基?1?硝酰氧乙基咪唑)二(5?硝基四唑)盐的爆速和爆压介于2,4,6?三硝基甲苯(TNT)和黑索今(RDX)之间,表现出较好的爆轰性能。     

3,4,5-三硝基吡唑及其衍生物的研究进展

3,4,5-三硝基吡唑(TNP)作为唯一全碳硝化的吡唑类化合物,具有高密度、高能量、低感度的优点,在含能材料领域具有广阔的应用前景。综述了TNP及其共价型衍生物、含能离子盐(金属盐及非金属盐)的合成、性能及应用的研究现状。从分子层面的角度论述了TNP为骨架的含能化合物的分子设计。认为今后此类含能化合物的研究应着重下面几个方向:TNP新的合成思路及工艺优化;1-氨基-3,4,5-三硝基吡唑(ATNP)及1,3,4,5-四硝基吡唑的合成及性能研究;TNP与其他富氮基团组成新型含能化合物的分子设计与合成;TNP及其衍生物的应用研究。     

硝基吡唑类化合物的合成研究进展

综述了12种硝基吡唑化合物的合成方法并进行了比较,重点介绍了能量高于2,4,6-三硝基甲苯(TNT)、感度低于TNT或能量更高的吡唑类低熔点系列含能化合物,如3,4-二硝基吡唑(3,4-DNP)、1-甲基-3,4,5-三硝基吡唑(MTNP),为此类含能化合物的进一步合成及性能研究提供一定的参考,为高密度、高能量、低感度炸药及可替代TNT的熔铸炸药载体的进一步研究探索提供一定的新思路。认为以下三个方面将会是今后一段时期内的研究重点:探索MTNP新合成路及工艺优化,研究3,4-二硝基吡唑和MTNP的物化性能及其高能化合物的组合配方,寻找硝基吡唑化合物合成中需求的绿色硝化剂和催化剂。     

多硝基3,3,7,7-四（三氟甲基）-2,4,6,8-四氮杂双环[3.3.0]辛烷的合成与性能

为了探索三氟甲基对含能材料性能的影响,以偕二氨基六氟丙烷和乙二醛为原料构建了氮杂稠环类含能材料的硝化前体——3,3,7,7-四(三氟甲基)-2,4,6,8-四氮杂双环[3.3.0]辛烷,通过改进的合成路线,用发烟硝酸多步硝化分别得到2,6-二硝基-3,3,7,7-四(三氟甲基)-2,4,6,8-四氮杂双环[3.3.0]辛烷(4)、2,4,6-三硝基-3,3,7,7-四(三氟甲基)-2,4,6,8-四氮杂双环[3.3.0]辛烷(5)和2,4,6,8-四硝基6-3,3,7,7-四(三氟甲基)-2,4,6,8-四氮杂双环[3.3.0]辛烷(6)。利用核磁共振氢谱、碳谱和氮谱表征了产物结构;采用排惰性气体法测试了三种硝化产物的密度,其中6的密度最大,高达2.08 g·cm~(-3);分别用落锤升降法和BAM法测得三种产物的撞击感度均大于30 J、摩擦感度均大于360 N;热重-微商热重(TG-DTG)分析发现三种产物的质量损失均大于90%,其热稳定性随硝基的增加而下降;利用Gaussian 09计算包,通过Monte-Carlo统计学方法以及Kamlet-Jacbos方程和VLW爆轰产物状态方程等理论模型预估了产物的爆速、爆压,其中化合物6的爆速为1 1937 m·s~(-1),爆压为74.3 GPa。与四硝基甘脲(TNGU)的性能及感度对比发现,在含能材料的分子结构中引入具有更高密度和更大电负性的三氟甲基,可在维持较高密度和良好爆轰性能的同时降低感度。     

二硝基脲的合成、表征及热力学的理论研究

二硝基脲(DNU)是环状硝胺类含能化合物的重要前体原料.以尿素为原料,经硝化反应合成了二硝基脲,并分离得到了中间体硝基脲,优化了反应条件.在20%发烟硫酸与100%硝酸体积比为0.6/1时,一阶段温度-1 5℃,二阶段温度5℃,反应50 min,二硝基脲收率可达83.2%.采用B3LYP法,在6-31+G(d,p)基组...     

联唑类含能化合物及其含能离子盐研究进展

联唑类含能化合物及其含能离子盐是近年发展起来的一类新型含能材料,具有高氮含量、高生成焓、高爆轰性能和相对钝感等特性,在新型炸药、低特征信号推进剂、气体发生剂、低烟或无烟烟火等领域有着广泛的应用前景。综述了有关联-1,2,4-三唑、联四唑和5-(1,2,4-三唑)四唑等联唑类含能化合物及其含能离子盐的最新合成研究成果,并对部分化合物的物化性能进行了阐述。认为下一步的工作重点为研究富氮阳离子的引入对联唑类含能化合物感度和爆轰性能的影响,合成出综合性能更好的联唑类含能化合物。设计了9种新型联唑类含能化合物,并利用量子化学方法对其性能进行预估。     

二硝基脲含能离子盐的合成及表征

利用三唑类、咪唑类化合物以及乙二胺与二硝基脲反应,合成了一系列二硝基脲含能离子盐,采用IR、1H NMR、13C NMR、元素分析等手段对这些盐的结构进行了表征.结果表明,乙二胺与二硝基脲形成二价盐,其它几种化合物形成二硝基脲的一价盐.热分析结果显示,二硝基脲成盐有效提高了其热稳定性,从热重曲线可以看出,乙二胺二硝基脲...     

硝基脲类含能材料的合成及性能研究进展

系统综述了国内外关于硝基脲类含能材料的合成和性能研究进展。重点介绍了硝基五元环脲类尤其是甘脲类含能材料的合成与性能。认为,硝基脲类含能材料具有较好的热稳定性、较高的密度和能量水平,但双硝基脲类化合物的水解稳定性差限制了其应用。指出,甘脲类含能材料和七、八元环硝基脲类含能材料研究相对较少。可考虑设计良好的氮杂环骨架分子,骨架分子中引入硝仿基(—C(NO2)3)、硝基(—NO2)、氨基(—NH2)和硝氨基(N—NO2)等含能基团来合成新型化合物,以提高硝基脲类化合物的实际应用价值。提出了设计与合成新型硝基脲类含能材料的研究方向,附参考文献52篇。     

Nitrosation and Nitration of Tetraacetyldibenzylhexaazaisowurtzitane

Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.     

A Robust Algorithm for Watermarking 2D Vector Maps with Low Shape-Distortions

The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS （geographical information system） data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.     

Open Rule-setting System Applied to Conceptual Design of Engines

Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.     

Research on Linux Network Device Driver

By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux （kernel version 2.6.11 ） is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.     

Improvement and Experiment of the Reamer in Vibra Cutter Against Wave Edge of Titanium Sheet Alloy Parts

By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.     

Experimental Study on the Small Flyer Initiating Behavior of Fine-grained Explosives

The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.     

Algorithm for Multi-laser-target Tracking Based on Clustering Fusion

Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.     

Robust Graded Sliding Mode Tracking Control for Low Speed Spinning Ballistic Missiles

The nonlinear dynamic model of spinning ballistic missiles is established during the first boosting phase of the missile. Based on the conventional backstepping sliding mode control and the assumption of a two time-scale separation of missile dynamics, a graded sliding mode controller is designed with two sub-sliding surfaces which have invariability to external disturbances and parameter perturbations, and a matrix which comprises three first order low pass filters is introduced to prevent ＂explosion of terms＂. Owing to the upper bounds of the uncertainties are difficult to obtain in advance, adaptive laws are introduced to estimate the values of the uncertainties in real-time. Eventually, the numerical simulation results given to show the proposed controller can ensure the steady flight of missiles.     

A Study on the Estimation of Aeroheating upon the Warhead Nose at Supersonic Speed

An expression for estimating the aeroheating on a warhead nose at different supersonic speeds is proposed by incorporating CFD （computational fluid dynamics） and the least-square method. Compared with the traditional estimation formula, the expression is more accurate, convenient and can be used in the optimized design of warheads. The error from the result obtained in the test of a ball cartridge flight is less than 3 %. It satisfies the engineering requirements.     

Influence of Installing Error on the Surface Shape Precision of the Axial Symmetry Aspheric Workpiece in Lapping

A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.