DDI/IPDI固化聚氨酯力学性能及其在PBX炸药中的应用

研究了新型混合固化剂二聚脂肪酸二异氰酸酯(DDI)/异佛尔酮二异氰酸酯(IPDI)固化端羟基聚丁二烯(HTPB)基聚氨酯的力学性能及其在PBX炸药中的应用。结果表明,当混合固化剂中DDI与IPDI的异氰酸酯基(NCO)的摩尔比为1/3时,HTPB基聚氨酯的拉伸强度和延伸率达到最大值(0.427 MPa和579.9%)。当DDI与IPDI的NCO摩尔比为1/1时,聚氨酯的压缩失效载荷最高。DDI/IPDI固化的HTPB基聚氨酯的延伸率是甲苯二异氰酸酯(TDI)固化聚氨酯的2.51倍。DDI/IPDI固化的PBX炸药的压缩率比使用TDI提高57.3%。使用DDI/IPDI时,PBX药片撞击感度试验和药片剪切试验的反应阈值提高了0.25 m以上,PBX的撞击安全性得到改善。     

不同分子量HTPB与TDI的固化反应动力学

测定了浇注高聚物粘结炸药(PBX)粘结剂固化反应的放热量,探讨了端羟基聚丁二烯(HTPB)分子量对固化反应速率的影响。采用非等温差示扫描量热法(DSC)研究了分子量分别为1500(M1)和2800(M2)的HTPB与2,4-甲苯二异氰酸酯(TDI)固化反应的动力学。结果表明,M1固化体系比M2固化体系的粘度增长迅速,固化放热量大。M1体系固化反应表观活化能约为55.87 kJ·mol-1,反应级数为0.88,指前因子为4.70×10⁴ s-1; M2体系的固化峰温升高,表观活化能、反应级数和指前因子分别提高至60.77 kJ·mol-1、0.89、1.07×10⁵ s-1,M1与M2体系反应机理函数仍遵循n级反应模型f(α)=(1-α)ⁿ,方程中的指数n有所变化。     

HTPB 基浇注PBX 炸药固化反应动力学研究

为研究端羟基聚丁二烯(hydroxyl-terminated polybutadiene,HTPB)基浇注PBX炸药的固化反应特性确定其固化工艺参数,采用非等温DSC法研究HTPB基浇注PBX炸药粘接剂体系固化反应动力学.分别测试升温速率为5、10、15、20 K/min时的DSC数据,得出固化反应动力学方程,计算不同温度下的反应速率常数,绘制固化速率(dα/dt)～固化度(α)关系曲线,并给出常用HTPB基浇注固化炸药的固化温度范围.结果表明:相同固化度条件下,升温速率越大,固化反应速率越大,当固化度达到0.5时,固化反应速率达到最大值,此后逐渐降低,直至为零.     

基于新型聚氨酯弹性体材料在PBX 炸药载体中的应用

为提高高聚物粘结炸药(polymer bonded explosive,PBX)炸药载体的力学强度,在炸药的粘结剂体系中引 入聚氨酯弹性材料进行聚醚/聚酯粘结剂高强度载体设计。通过调控聚氨酯弹性体制备过程中多元醇的比例和分子 量、固化剂的种类,利用旋转流变仪和多功能万能材料试验机开展材料固化速率性能分析和固化后聚氨酯弹性体对 端羟基聚丁二烯(hydroxyl-terminated polybutadiene , HTPB)粘结剂体系力学强度影响规律分析。结果表明： PCL_PTMG 聚氨酯弹性体拉伸强度的大小与固化剂的固化速率相关;改变聚酯聚醚分子量对弹性体抗拉强度的影响 不大;当聚酯聚醚的比例为4:1 时,弹性体抗拉力学强度最优;聚氨酯弹性体增大了HTPB 粘结剂体系强度。     

仿生疏液表面对浇注PBX药浆的低黏附性能研究

降低浇注高聚物粘接炸药(PBX)药浆与接触材料的黏附作用是提高浇注固化PBX制备工艺水平和效率的关键因素之一。采用溶液刻蚀方法在接触容器金属表面构筑微米-纳米多级复合仿生结构,使高黏液端羟基聚丁二烯(HTPB)和浇注PBX药浆在金属表面的静态接触角均大于130°,表面具有良好的疏液性能,且通过调整刻蚀时间为120 min时,在金属表面形成仿花状的微纳米复合结构,可使金属表面与HTPB、HTPB/Al和HTPB/1,1-二氨基-2,2-二硝基乙烯(Fox-7)药浆间的黏附作用力分别降低至29.4,46.0μN和12.7μN,下降幅值达57%～82%。同时将仿生结构涂覆于模具内表面,宏观实现对PBX药浆不黏附特性。     

一种改性HTPB型聚氨酯的力学性能研究

采用过氧乙酸原位法对端羟基聚丁二烯(HTPB)进行环氧化改性,制备出不同环氧值的环氧化端羟基聚丁二烯(EHTPB).将EHTPB分别与甲苯二异氰酸酯(TDI)、异佛尔酮二异氰酸酯(IPDI)和4,4-二环己基甲烷二异氰酸酯(H12MDI)三种异氰酸酯类固化剂以及扩链剂1,4-丁二醇(BDO)固化交联形成聚氨酯,然后对聚氨酯的力学性能进行了研究,并利用红外和扫描电镜(SEM)对其结构进行了分析.结果表明：对于产物力学性能,H12MDI是一种更好的固化剂;EHTPB环氧值最佳值控制在0.18mol·(100g)-1为好;加入扩链剂BDO可以提高产物的力学性能,BDO的最佳加入量为BDO的—OH与HTPB的—OH的摩尔比为1～2,EHTPB/H12MDI/BDO体系具备最佳的力学性能.     

浇注PBX固化行为的实验与模拟

采用动态流变学实验对浇注高聚物黏结炸药(PBX)固化过程的宏观性质表现进行了测试。结果表明,PBX的储能模量(G′)和损耗模量(G″)随固化时间逐渐增大,且G′逐渐接近并超过G″,二者最终趋于稳定。通过分子动力学方法模拟了PBX黏结剂端羟基聚丁二烯(HTPB)与交联剂甲苯二异氰酸酯(TDI)之间固化反应的微观过程,并对体系固化各阶段的力学性能进行了计算。模拟结果与流变实验结果之间具有较高的一致性,说明分子动力学模拟可为PBX的固化行为研究提供微观信息。     

高强度CL-20/HTPE基微尺度传爆药的打印成型及性能表征

为了研制出力学性能优异的微机电系统（MEMS）火工品用微尺度传爆药,以六硝基六氮杂异伍兹烷（CL-20）为主体炸药,以端羟基聚醚（HTPE）/硝化纤维素（NC）为复合黏结体系,以乙酸乙酯为共溶剂,加入一定量的甲苯二异氰酸酯（TDI）设计出一种全溶式炸药油墨,利用喷墨打印技术实现了高精度装药成型,利用异氰酸根与羟基的交联反应实现了微装药力学性能增强。采用电子密度仪、扫描电子显微镜、差示扫描量热仪、X射线衍射仪、纳米压痕仪分别对打印样品的密度、微观形貌、热安定性、炸药晶型和力学性能进行了表征。结果表明,打印样品实测密度为1.70 g·cm^-3,可达最大理论密度的88.54%,打印样品中CL-20由ε晶型转变为β晶型,其热分解表观活化能为173.00 kJ·mol^-1,比原料CL-20提升了13.17 kJ·mol^-1。打印样品弹性模量可高达10.47 GPa,硬度为0.22 GPa,展现了良好的力学性能。喷墨打印装药具有良好的传爆能力,临界爆轰尺寸和爆速分别为1 mm×0.18 mm和8054 m·s^-1。     

浇注高聚物粘结炸药的粘结剂体系设计及其应用研究

为提高端羟基聚丁二烯(HTPB)基浇注高聚物粘结炸药(PBX)的固相含量、力学性能,并降低渗油性,采用己二酸二辛酯和壬酸异癸酯为原料,根据溶度参数近似原理设计了一种复合 增塑剂AI.基于HTPB/AI粘结剂体系制备出固相含量达到90%的浇注PBX,研究了PBX的机械感度、热分解、固相含量等与粘结剂体系的关系。结果表明：复合增塑剂AI降低了HTPB胶片的模量,从而降低了PBX的机械感度;AI降低了浇注PBX药浆黏度,提高了固相含量,从而提升了能量水平;对原材料进行高温真空旋蒸处理,降低了原材料中水分等杂质的含量,从而降低了PBX的渗油性,提高了复合增塑剂的安定性及其与PBX配方中其他组分的相容性。     

壳体约束下浇注PBX的温度适应性

为研究壳体约束条件下浇注高聚物黏结炸药(PBX)的温度适应性能,制备了组分为奥克托今(HMX)/端羟基聚丁二烯(HTPB)/2,4-甲基二异氰酸酯(TDI)的炸药,分别装填Ф20 mm×20 mm、Ф15 mm×65 mm、Ф100 mm×200 mm、Ф150 mm×300 mm和Ф200 mm×400 mm五种尺寸的试样,其中后者三种较大尺寸的试样还分为无缺陷和有预制缺陷两种形式。利用-55~70℃温度冲击和温度循环试验,研究了浇注PBX的内部损伤、壳体外部温度和应变以及炸药尺寸、密度和力学性能变化。结果表明,温度冲击和温度循环试验后,浇注PBX没有明显的热损伤,原有缺陷也没有明显扩展;随着试验件尺寸的增大,通过升降温达到温度平衡所需的时间延长,高低温应变变化呈现减小的趋势。试验后炸药密度增大0.001 g·cm~(-3),拉伸强度和压缩强度分别提高了0.12 MPa和0.55 MPa。     

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.     

Stability of the Third Generation Intensifier under Illumination

The stability under illumination of transmission-mode GaAs photocathode sealed in the third generation intensifier is investigated by use of spectral response testing instruments. The variations of spectral response with the illumination times under weak and intense illumination are compared. The variations of photoemission performance parameters are also characterized. The results show that during initial several weak illuminations photocathode behaves no evident decay and a maximum sensitivity is achieved, while under intense illumination the sensitivity of photocathode begin to decrease largely at the first illumination. The calculated performance parameters show that the variation of surface escape probability with illumination times is a direct cause of instability of photocathode. It is also found that under intense illumination peak wavelength is moved towards short-wave and peak response is decreased, which shows that the ability of long-wave response of photocathode is decreased.     

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.     

Passive Acoustic Radar for Detecting Supersonic Cruise Missile

A Passive Acoustic Radar is presented as a necessary complement to electromagnetic wave radar, which will be expected to be an effective means for detecting cruise missiles. Acoustic characteristics of supersonic flying projectiles with diverse shapes are expounded via experiment. It is pointed out that simulation experiment could be implemented using bullet or shell instead of cruise missile. Based on theoretical analysis and experiment, the ““acoustic fingerprint““ character of cruise missile is illustrated to identify it in a strong noise environment. After establishing a locating mathematical model, the technique of acoustic embattling is utilized to resolve a problem of confirming the time of early-warning, considering the fact that velocity of sound is much slower than that of light. Thereby, a whole system of passive acoustic radar for detecting supersonic cruise missile is formed.     

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.     

Super-resolution Restoration of Remote-sensing Images

A novel image restoration scheme, which is super-resolution image restoration algorithm Poisson-maximum-afterword-probability based on Markvo constraint （MPMAP） combined with evaluating image detail parameter D, has been proposed. The advantage of super-resolution algorithm MPMAP incorporated with parameter D lies in the fact that superresolution algorithm MPMAP model is discrete, which is in accordance with remote-sensing imaging model, and the algorithm MPMAP is proved applicable to linear and non-linear imaging models with a unique solution when noise is not severe. According to simulation experiments for practical images, super-resolution algorithm MPMAP can retain image details better than most of traditional restoration methods; at the same time, the proposed parameter D can help to identify real point spread function （PSF） value of degradation process. Processing result of practical remote-sensing images by MPMAP combined with parameter D are given, it illustrates that MPMAP restoration scheme combined PSF estimation has a better restoration result than that of Photoshop processing, based on the same original images. It is proved that the proposed scheme is helpful to offset the lack of resolution of the original remote-sensing images and has its extensive application foreground.