一种碳膜桥的点火特性研究

以类石墨碳膜为点火材料制作了碳膜电点火桥,研究了温度对碳膜电点火桥阻值和发火性能的影响,并比较了两种常用起爆药剂的碳膜电点火桥的发火性能,同时对碳膜电点火桥进行了脚-脚间抗静电测试。结果表明:碳膜电点火桥是一类具有负温度系数、发火区间小、散步精度高、安全性高且制作简便的点火件,具有极强的应用前景。     

新型碳基导电药无桥火工品研究

为开发抗静电能力强、制作工艺简单的新型火工品,利用碳纤维独特形状及特殊电热转换特性,将其分别与叠氮化铅（LA）、斯蒂芬酸铅（LS）和叠氮肼镍（NHA）混合制备了碳基含能复合起爆药（CEC）,并用于陶瓷塞火工品和M100独脚电雷管。通过改变碳纤维含量,研究了CEC火工品发火性能及静电感度等性能。发火特性及安全性实验结果表明：当碳纤维添加量为30%时,火工品发火电压最低,3种火工品50%发火电压由低到高依次为NHA-CEC火工品（14.1 V）、LS-CEC火工品（17.6 V）和LA-CEC火工品（27.8 V）,安全电流分别为280 mA、250 mA和180 mA,其对应的脚-脚间50%发火静电电压分别为28.9 kV、27.3 kV和30 kV,脚-壳间抗静电能力大于25 kV. 高速摄影和雷管铅板实验结果表明：3种火工品均具有可靠的点火能力,其中LA-CEC和NHA-CEC能可靠起爆黑索今炸药并将铅板炸穿。相比于桥丝火工品和半导体桥火工品,该碳基含能复合物装配的无桥火工品具有抗静电能力好、制备方法简便、成本低廉的优点。     

降低半导体桥/斯蒂芬酸铅发火能量的技术途径研究

进一步降低半导体桥（SCB）换能元件发火能量是微机电系统（MEMS）引信用微型起爆系统发展的瓶颈技术。通过发火感度试验,获得了减小桥区尺寸、增加V型缺口、适当长宽比、降低药剂粒度等是降低SCB发火能量的有效技术途径。在试验方案范围内获得最小全发火电压3.83 V,发火能量0.073 mJ,最大不发火电流229.88 mA. 分析发火现象和电特性曲线得出：SCB换能元的桥区面积7.65×10² μm²,质量3.55×10^-6 mg,临界发火属于电热发火;桥区面积5.68×10² μm², 质量2.64×10^-6 mg,临界发火属于电爆发火。进一步降低半导体桥（SCB）换能元件发火能量是微机电系统（MEMS）引信用微型起爆系统发展的瓶颈技术。通过发火感度试验,获得了减小桥区尺寸、增加V型缺口、适当长宽比、降低药剂粒度等是降低SCB发火能量的有效技术途径。在试验方案范围内获得最小全发火电压3.83 V,发火能量0.073 mJ,最大不发火电流229.88 mA. 分析发火现象和电特性曲线得出：SCB换能元的桥区面积7.65×10² μm²,质量3.55×10^-6 mg,临界发火属于电热发火;桥区面积5.68×10² μm², 质量2.64×10^-6 mg,临界发火属于电爆发火。     

纳米多孔铜/高氯酸钠复合物电点火头的原位制备方法

为制备纳米多孔铜/高氯酸钠复合物电点火头,以焊有桥丝的脚线为阴极,大面积紫铜片为阳极,采用电沉积法在桥丝上原位沉积纳米多孔铜;将沉积有纳米多孔铜的桥丝浸入高氯酸钠饱和溶液制得纳米多孔铜/高氯酸钠复合物电点火头.采用SEM,EDS,XRD等手段对复合物进行表征,采用DSC研究了复合物的热分解性能,表明在402.09℃处有一尖锐的放热峰,放热量为171.8J/g.采用直流发火和脉冲电流发火的方法测得电点火头50%发火感度分别为0.55A和0.47A,两种测量方法的标准偏差分别为0.114和0.005;且在22μF电容、32V的测试条件下电点火头不发火.该方法将火工品药剂的原位合成与火工品的制造有效结合,避免了电点火头生产过程中操作者与药剂的直接接触,有利于提高生产过程中的安全性.     

半导体桥对含能材料的点火特性研究

在10μF钽电容放电激励下,对两种阻值相当质量不同的半导体桥(SCB)和细化的发火药剂斯蒂芬酸铅(LTNR)和叠氮化铅(PbN6)所组成的发火件进行了实验研究,根据发火件的电特性变化和发火现象发现半导体桥存在电热发火、电爆发火和等离子体发火三种情况,测试了SCB/LTNR和SCB/PbN6发火件的50%发火电压和发火时间。结果表明半导体桥的发火电压阈值不仅与发火药剂有关,还与半导体桥换能元有关,所以半导体桥的设计存在最佳质量,通过对比得知LTNR比PbN6感度高,PbN6比LTNR的燃速高。     

半导体桥静电作用前后点火特性

对静电作用过的半导体桥和未经受静电作用的半导体桥进行D-最优化点火实验,得到全发火电压,并在全发火电压下点火,用示波器采集电压、电流以及发火时间等信号,用显微镜观察桥面的烧蚀情况并计算烧蚀面积。分析得到:静电对半导体桥的桥膜产生了损伤,静电电压越大,烧蚀面积越大;经过静电作用的桥与未静电作用的桥相比,全发火电压降低,发火能量减小,桥变得更加敏感。对全发火电压下的发火能量和发火时间进行t检验,得到21 kV是临界值,静电电压大于21 kV,静电对桥的性能影响明显;小于21 kV,静电对桥的影响不大。     

温度对半导体桥电爆性能影响初探

为了研究温度对半导体桥（SCB）电爆和点火的影响,采用电容放电激励的方式,研究了SCB在环境温度分别为25℃和-40℃的电爆特性,建立数学模型并探讨了环境温度对SCB电爆的影响;开展了以Al/CuO纳米铝热剂为点火药剂的SCB点火感度实验,在环境温度为25℃和-40℃测试了Al/CuO纳米铝热剂的点火温度,并采用Neyer D最优化法测试SCB点火感度。结果发现,当充电电压由30 V增加至50 V时,电爆延迟时间差值由0.47μs降低至0.25μs,电爆所需能量的差值由0.16 mJ增加至0.65 mJ,表明随着充电电压的增加,环境温度对电爆延迟时间的影响减小,对电爆所需能量的影响增大;并发现不同温度下Al/CuO纳米铝热剂点火温度没有显著差异,为740.7℃;-40℃时的SCB临界发火电压比25℃时高0.6 V。     

纳米Al-MoO_3发火性能研究

为研制高能量密度无铅的火工药剂,以纳米铝粉和纳米氧化钼为原料,采用超声分散混合的方法,制备了绿色环保的纳米含能材料Al-MoO3。通过冷场扫描电镜和差热分析(DSC)对纳米含能材料Al-MoO3进行了表征分析,制作了电点火头和激光点火头,进行了点火性能测试。结果表明:纳米含能材料Al-MoO3在520℃以上的高温条件下反应,放出大量的热,其中电点火头的50%的电压发火感度为22.8V,激光点火头的50%的发火感度为5.1mJ。     

叠氮化铅半导体桥点火研究

利用半导体桥(Semiconductor Bridge,SCB)作为发火元件点燃叠氮化铅(Lead Azide,LA),获得了其电压电流曲线,通过分析其电压电流曲线和烧蚀后的桥面,发现两种不同的点火机理:当LA的颗粒较大时(45μm),利用SCB产生的等离子体将药剂点燃;当LA的颗粒较小时(1μm),SCB不产生等离子体就可以将药剂点燃。非等离子体点火时,其发火电压约为等离子体点火时的20%,降低了SCB的点火能量。此外,压药压力对非等离子体点火的最低发火电压有一定影响,80MPa时其发火电压最低。     

斯蒂芬酸铅的半导体桥点火试验研究

通过对半导体桥(Semiconductor Bridge,SCB)装药条件下发火电压、发火电容及积分能量对点火时间影响的对比,结合不同点火条件下,桥体两端电压曲线、电流曲线和电流二次峰出现时间的比较,研究了斯蒂芬酸铅(LTNR)的半导体桥点火机理。试验发现特定的点火电路下,SCB点火时间存在一个临界值,且SCB等离子体形成的快慢直接影响点火时间。在充电电压从大到小的点火过程中,在桥与药剂之间存在2种不同的点火机理,在较高点火电压下为等离子体点火机理,在低电压为热点火机理。     

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.     

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.     

Experimental Research on Output Performances of Giant Magnetostrictive Actuator

The paper introduces the performances of magnetostrictive actuators and its applications, discusses the design methods for the structure and internal magnetic circuit of a giant magnetostrictive actuator, and makes tests on the output displacement and force characteristics for an actuator using homemade magnetostrictive material. The experimental result shows that the actuator has satisfactory output precisions and ranges in transient and stable states, and can be used in lowfrequency vibration control system of precise equipment.     

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.