Study on Design and Safety Evaluation Methods of Mechanical-Thermal Weak-Link

In an abnormal high-temperature fire environment,a structure with mechanical-thermal weak-link can be used to predict the permanent failure before the failure of some strong-links,such as explosive initiator,thus to protect the latter. An effective design can be defined as that the weak-link fails before the failure of the strong-link,and the system is safe; while an unsuccessful design means that the weak-link fails after the failure of the strong-link,and the system loses in safety. The probability of safety failure exists due to the uncertain failure temperatures of the weak-link and strong-link. In order to obtain the probability of safety failure,a statistical method was used to deal with the uncertainty of the failure temperatures. The integral method and stochastic simulation method were used in calculations. Finally,a sample was given to verify the consistence of the results given by two methods.     

Customization Product Design Based on User‘s Emotion and Needs

The paper presents a design method that ensures the ingenuity of the product form as well as the whole and exact expression of user‘s needs. The key idea is to establish an automatic design system which can transform the users language needs into the product features in real-time. A rifle was taken as a research instance and soldiers were chosen as evaluation customers. The theory of fuzzy set and semantic difference are adopted to evaluate the relationship between user‘s needs and product features as well as their alternatives. FAHP (fuzzy analytic hierarchy process) is utilized to judge the users satisfactory forms. This method can also be applied to other product form designs.     

A Classification Algorithm for Ground Moving Targets Based on Magnetic Sensors

A novel classification algorithm based on abnormal magnetic signals is proposed for ground moving targets which are made of ferromagnetic material. According to the effect of diverse targets on earth's magnetism,the moving targets are detected by a magnetic sensor and classified with a simple computation method. The detection sensor is used for collecting a disturbance signal of earth magnetic field from an undetermined target. An optimum category match pattern of target signature is tested by training some statistical samples and designing a classification machine. Three ordinary targets are researched in the paper. The experimental results show that the algorithm has a low computation cost and a better sorting accuracy. This classification method can be applied to ground reconnaissance and target intrusion detection.     

A Rapid Method for Compensating Output Error of Electromagnetic Tracker

Some methods which use an optical tracker （OT） as a standard reference of electromagnetic tracker （EMT） were proposed in order to compensate the output error of electromagnetic tracker. Usually, they use a magneto-optic tool to collect the outputs of OT and EMT simultaneously, and then compare the output of OT with that of EMT to compensate the error of EMT. Although the outputs of EMT and OT can be matched each other by using a time stamp which denotes when the acquirement command is sent, but the accuracy will decrease if the tool moves faster for the errors of the time stamp itself. A rapid method for compensating EMT output error is proposed. A particular scan mode of the magneto-optic tool is designed for collecting EMT and OT outputs, and a data registration method is proposed to match the outputs of EMT and OT. The simulated results show that the output error of EMT can be decreased efficiently and the accuracy of the compensation can be improved by about 15 % compared with that of the existing methods.     

Experiment and Calculation for Expansion Process of Ablation Plasma Jets in Liquid

The expansion process of ablation plasma jet in liquid was experimentally investigated by using high speed digital camera. The sequential pictures show that, in the initial stage of the jet, the Taylor cavity expands in the axial and radial directions simultaneously, and then, is subjected to the constraint of chamber wall, in axial direction mainly. The maximum axial speed of the cavity's head ranges from 240m/s to 280m/s. Some strong heat conduction and mass transmission effects can be found in the surface of Taylor cavity, where the plasma cools down and condenses as solid particles while the liquid vaporizes as gas. Compared the expansion processes of the cavities among the different discharge energies and the nozzle diameters, it can be seen that the expansion speed of the cavity is directly proportional to the discharge energy and inversely to the nozzle diameter, and the effect of the discharge energy is stronger than that of the nozzle diameter. A set of equations describing the expansion process of ablation plasma jet was derived under the assumption of momentum conservation. The calculated results by use of the equations coincide with the experimented results better.     

Underwater Localization for Multiple AUVs Based on Bearing and Range Measurements

A novel underwater localization algorithm for autonomous underwater vehicle （AUVs） is proposed. Taking aim at the high cost of the traditional ＂leader-follower＂ positioning, a ＂parallel＂ model is adopted to describe the localization problem. Under an unknown-but-bounded assumption for sensor noise, bearing and range measurements can be modeled as linear constraints on the configuration space of the AUVs. Merged these constraints, a convex polyhedron representing the set of all configurations consistent with the sensor measurements can be induced. Estimates for the,uncertainty in the position of a single AUV or the relative positions of two or more AUVs can then be obtained by projecting this polyhedron into appropriate subspaces of the configuration space. The localization uncertain region for each AUV can be recovered by an approximation algorithm to realize underwater localization for multiple AUVs. The deduced theoretically and the simulated results show that it is an economical and practical localization method for the AUV swarm.     

Formation of explosively formed penetrator with fins and its flight characteristics

The ultimate goal of weapon system employing an explosively formed penetrator （EFP） is to defeat a target at the longest standoff. In order to do this, an EFP must be aerodynamically stable so as to strike the target at a small angle of obliquity, and the decay velocity per meter of EFP must be smaller at extended standoff. As the angle of attack increases, the penetration ability of EFP greatly reduces. The fins improve the EFP aeroballistic characteristics and decrease the flight drag of EFP as well, EFP with fins formed by three-point initiation is presented. The for- mation of EFP with fins is studied by LS-DYNA, and the aeroballistics is studied through experiment. The experimental results show that the decay velocity per meter of EFP with fins is much smaller than that of normal EFP, and the attitude angle steadily decreases.     

Estimation of the kinetic parameters for thermal decomposition of HNIW and its adiabatic time-to-explosion by Kooij formula

A differential/integral method to estimate the kinetic parameters （apparent activation energy Ea and pre-exponential factor A） for thermal decomposition reaction of energetic materials based on Kooij formula are applied to study the nonisothermal decomposition reaction kinetics of hexanitrohexaazaisowurtzitane （HNIW） by analyzing nonisothermal DSC curve data. The apparent activation energy （Ea） obtained by the integral isoconversional non-isothermal method based on Kooij formula is used to check the constancy and validity of apparent activation energy by the differential/integral method based on Kooij formula. The most probable mechanism function of thermal decomposition reaction of HNIW is determined by a logical choice method. The equations for calculating the critical temperatures of thermal explosion （T_b） and adiabatic time-to- explosion （t_Tlad） based on Kooij formula are used to calculate the values of Tb and t_Tlad to evaluate the thermal safety and heat-resistant ability of HNIW. All the original data needed for analyzing the kinetic parameters are from nonisothermal DSC curves. The results show that the kinetic model function in differential form and the values of E_a and A of decomposition reaction of HNIW are 3（1 - α）[-ln（1 - α）]2/3, 152.73 kJ mol 1 and 10~11.97 S 1, respectively, and the values of self-accelerating decomposition temperature （T_SADT）, Tb and t_Tlad are 486.55 K, 493.11 K and 52.01 s, respectively.     

Real-time Extraction of Target Position Information Based on Bi-orthogonal Wavelets

Extraction of flying target position information is the prerequisite for passive infrared guided missiles to track the target. The existing missile detection system senses the target＇ s infrared radiation, and then the generated signal is sent to signal processing circuits for extracting the target position information. In order to improve anti-interference capacity of the detection system, an algorithm of module maximum edge detection based on the bi-orthogonal wavelets is proposed to replace its hardware. The signal can be decomposed in one layer, only its high frequency detail is reconstructed. After some calculations, the average target position can be obtained. The algorithm＇s real-time implementation with DSP is also discussed. To reduce the execution time, the program structure can be optimized with double buffers in memory. This im- plementation is verified by simulations. The results show that the method has only a small amount of calculations, can meet the requirements for finding out the target position in real-time and needs not the traditional processing circuit.     

Research on Complex Refraction Indices of Expanded Graphite

The expanded graphite (EG) with a low density and better extinction performance can be used in military as passive jamming material in IR and MMW bands. Its complex refractive index is a significant parameter for the extinction property. This paper presents a method to calculate the complex refractive index of EG. The reflection spectra of EG pellets were measured in the 0.24-2.6μm and 2.5-25μm bands, respectively. Based on the measurement results, the complex refractive index of EG in 5-10μm band was calculated by using Kramers-Kronig(K-K) relation and Bruggeman effective medium theory, and then the errors were analyzed. The results indicate that it is feasible to calculate the complex refractive index of EG based on its IR reflection spectra data.     

Pd(OH)2/CeO2在六苄基六氮杂异伍兹烷和四乙酰基二苄基六氮杂异伍兹烷催化氢解脱苄反应中的应用

Pd(OH)2催化剂对六硝基六氮杂异伍兹烷(CL-20)的制备具有关键作用.选择CeO2为催化剂载体,用沉积-沉淀法制备8种Pd(OH)2/CeO2催化剂,考察制备温度、浸渍时间、碱源、沉淀pH及载体结构对Pd(OH)2/CeO2催化氢解脱苄反应活性的影响.结果表明:Pd(OH)2/CeO2可同时作为六苄基六氮杂异伍兹...     

降低由四乙酰基二苄基六氮杂异伍兹烷制备的六硝基六氮杂异伍兹烷中杂质含量研究

由四乙酰基二苄基六氮杂异伍兹烷(TADBIW)制备六硝基六氮杂异伍兹烷(HNIW),产品为纯γ晶型,得率达90%,纯度达98%以上.其中2%杂质主要为五硝基-乙酰基六氮杂异伍兹烷(PNMAIW).根据薄层色谱(TLC)和高效液相色谱(HPLC)分析结果,研究了HNIW得率及其中PNMAIW含量与硝解条件的关系.     

TATBIW与TADBIW的氢解反应特性

研究了六苄基六氮杂异伍兹烷 (HBIW) 的氢解不完全产物三乙酰基三苄基六氮杂异伍兹烷(TATBIW)对氢解产品四乙酰基二苄基六氮杂异伍兹烷(TADBIW)的二次氢解反应产生的影响.结果表明,TATBIW较TADBIW稳定性差,在甲酸介质中易于破笼,且易引起二次氢解催化剂中毒;但当催化剂用量加大到1%时,仍可得到TATBIW氢解完全的产物三乙酰基三甲酰基六氮杂异伍兹烷(TATFIW).     

四乙酰基六氮杂异伍兹烷水解硝化反应研究

研究了四乙酰基六氮杂异伍兹烷在稀硝酸/催化剂介质中的水解硝化。在催化剂存在条件下,四乙酰基六氮杂异伍兹烷可在硝酸溶液中进行水解硝化,以95%以上得率制得纯度高于99%的六硝基六氮杂异伍兹烷。同时也找到了一种制备六硝基六氮杂异伍兹烷的新方法。     

Experimental Studies of Toxicity on HNIW and Its Intermediates

The polycyclic nitramine hexanitrohexaazaisowurtane（HNIW） is a compound of high energy density. HNIW can replace 1, 3, 5-trinitro-1, 3, 5-triazacyclohexane（RDX） or HMX, hut its toxicity is unknown. In this paper, HNIW, hexabenzylhexaazaisowurtzitane （HBIW）, tetraacetyldibenzulhexaazaisowurtzitane （TADBIW）, tetraacetyldiformylhexaazaisowurtzitane（TADFIW） and tetraacetylhexaazaisowurtzitane（TAIW）, which are intermediates of the synthesis of the HNIW, were selected as the tested objects in acute toxicity test, acute eye stimulation test and skin irritation test according to the standards of ＂chemical product testing method-401 ： acute oral toxicity test＂, ＂chemical product testing means-405： acute eye irritation/corrosion test＂ and ＂chemical product testing means-404： acute dermal irritation/corrosion test＂ of National Circumstance Protect Bureau. The results show that all of the five objects have no toxicity, no stimulation to eye and skin under the tested conditions.     

六硝基六氮杂异伍兹烷中杂质的结构表征及热分解研究

分别以四乙酰基二苄基六氮杂异伍兹烷( TADBIW)为硝解基质通过亚硝解／硝解一锅法和四乙酰基二甲酰基六氮杂异伍兹烷( TADFIW)为硝解基质通过硝硫混酸法制备六硝基六氮杂异伍兹烷(HNIW)．用柱色谱对HNIW的主要杂质进行分离,以FTIR、1H NMR、MS、元素分析确定主要杂质为五硝基一乙酰基六氮杂异伍兹烷( PNMAIW)和五硝基一甲酰基六氮杂异伍兹烷(PNMFIW)．PNMFIW与PNMAIW的DSC分析和动力学参数计算表明,前者的初始分解温度和分解峰温均比后者的高,且前者的分解表观活化能约为后者的2倍,这可能是因为,对于一取代基的五硝基六氮杂异伍兹烷六元环上的甲酰基比五元环上的乙酰基有助于笼型结构的稳定。     

超细HNIW机械感度的研究

采用喷射结晶的方法对HNIW(六硝基六氮杂异伍兹烷或CL-20)进行了细化,细化后HNIW的平均粒径为193.5nm.对超细HNIW的撞击感度及摩擦感度进行了研究.试验结果表明:与粗颗粒HNIW相比,超细HNIW的撞击感度明显降低,50%落高值从7.94cm增大为33.9cm;而摩擦感度变化不大,爆炸概率从74%增加到80%.     

HNIW嵌入大孔纤维膜的新结构含能复合物的制备（英）

为了满足狭窄空间高点火能量的需要,利用静电纺丝法和自组装法将高能的六硝基六氮杂异伍兹烷(HNIW)复合到大孔聚丙烯腈(PAN)纤维膜中制备了一种新的含能复合物.用扫描电镜、红外、热分析和燃烧残渣分析了其形貌、热性能和燃烧行为.结果表明,HNIW均匀分布在纤维膜上.二者的复合是物理过程,没有化学变化.与单纯PAN纤维膜相比,HNIW的加入增强了纤维膜的燃烧性能,并且HNIW的起始放热点也因为纤维的存在而提前38℃.在特定比例下纤维和HNIW可以完全反应.     

WPU-g-SAN的合成及其对HNIW的包覆

为了降低六硝基六氮杂异伍兹烷(HNIW,CL-20)的撞击感度,利用原位种子乳液聚合,以异佛尔酮二异氰酸酯(IPDI)、甲基丙烯酸-β-羟乙酯(HEMA)、苯乙烯(S)、丙烯腈(AN)等为原料合成了用于降感的接枝型水性聚氨酯(WPU-g-SAN),采用红外光谱(FTIR)、核磁共振(1H NMR)、X-射线衍射(WAXD)及动态力学分析(DMA)对产物结构进行表征。结果显示所得产物为非晶结构,且存在微相分离。用制备的产物对HNIW进行包覆,通过X-射线光电子能谱(XPS)、扫描电镜(SEM)对包覆效果进行评价,并用GJB772A-1997方法测试了HNIW包覆前后的撞击感度。结果表明,包覆后的HNIW的特性落高H50由13.6 cm提高到28.5 cm。     

溶剂性质对六硝基六氮杂异伍兹烷晶型的作用

研究稳定地得到e型六硝基六氮杂异伍兹烷( HNIW)的结晶工艺条件,并寻求多晶转变的理论解释。研究发现,非溶剂的物理性质,如偶极矩、分子极性,在结晶过程中对于HNIW的晶型起重要作用。常温下在无晶种时,当利用乙酸乙酯、丙酮作为溶剂,采用偶极矩值小的非溶剂,如环己烷、石油醚、甲苯、异辛烷等均可使HNIW以ε型晶型结晶出来,反之,采用偶极矩值大的非溶剂,如三甘醇则使HNIW以其它晶型结晶出来。在较高温度下,s型HNIW在极性与非极性溶剂中稳定存在时间明显不同。