二元复合结晶炸药HMX/LLM-105的溶剂-非溶剂法制备研究

为降低1,3,5,7-四硝基-1,3,5,7-四氮杂环辛烷（HMX）的感度,采用溶剂-非溶剂法制备了二元复合结晶炸药HMX/LLM-105,并采用X射线粉末衍射（PXRD）、扫描电镜（SEM）、傅里叶变换红外光谱（FT-IR）对其进行表征;采用差示扫描量热法（DSC）分析其热分解性能,并进行了机械感度测试。结果表明：HMX/LLM-105的晶体形貌与原料单质炸药明显不同;HMX/LLM-105在放热过程中仅有1个放热分解峰,分解温度为271.6℃,放热效率更高;HMX/LLM-105的特性落高H50为68 cm,较HMX提高了42 cm,降感效果明显。     

升温速率对HMX炸药凝聚相热分解过程的影响研究

采用原位红外光谱研究了炸药1,3,5,7-四硝基-1,3,5,7-四氮杂环辛烷(HMX)在5,10,20,40℃·min-1四种不同升温速率下的热分解行为.研究结果表明随着温度的升高,C-N键的断裂速率远高于N-N键的断裂速率,表明C-N键的断裂是HMX的主要断键方式,在C-N键的断裂中伴随着N-N键的断裂.在5℃·min-1升温速率下,断裂的HMX环发生分子内结合,在10,20,40℃·min-1升温速率下,断裂的HMX发生分子间成环,重新形成稳定的八元环结构     

HMX溶液结晶的分子动力学模拟

采用分子动力学模拟研究了温度对奥克托今（ HMX）在二甲亚砜（ DMSO）溶剂中结晶的影响。计算了278～378 K温度范围内DMSO和HMX的扩散系数、HMX与DMSO分子间结合能。模拟了298 K下HMX在DMSO溶液中的成核过程。结果表明,HMX与DMSO分子间相互作用主要为范德华力与静电力。358 K时二者的结合能最小为20246 kJ · mol-1,此时HMX分子最易成核,成核导致HMX的扩散系数下降。     

基于溶剂/非溶剂法的微通道结晶制备CL-20/HMX共晶

为了发展易放大、可连续化的共晶制备方法,采用溶剂/非溶剂法的微通道结晶技术制备了六硝基六氮杂异伍兹烷/奥克托今(CL-20/HMX)共晶.采用场发射扫描电子显微镜(FE-SEM)、X射线粉末衍射(XRD)、拉曼光谱(Raman)、傅里叶红外光谱(FT-IR)、热分析和感度测试,对样品的形貌、结构、热性能和感度进行了表征分析.结果表明,该方法成功制备了CL-20/HMX共晶,其表观形貌部分呈花簇状,直径为20～30μm,由厚度为200～600 nm的片状晶体组装而成,部分呈单独的片状结晶(厚度为200～600 nm);所制备的CL-20/HMX共晶在放热过程中仅有一个尖锐的放热分解峰,放热峰温位于243.4℃,低于原料CL-20(250.2℃)和HMX(284.7℃).放热区间仅为242.7～246.0℃,比原料CL-20(230.0～254.6℃)和HMX(281.0～290.7℃)窄,具有较高的能量释放效率;表观活化能470.75 kJ·mol-1,介于CL-20(175.04 kJ·mol-1)和HMX(481.45 kJ·mol-1)之间,比CL-20提高了295.71 kJ·mol-1,具有较好的热稳定性;撞击感度为18 J,较原料CL-20(10 J)和HMX(14.4 J)分别提高8 J和3.6 J,摩擦感度比CL-20原料降低了20％,安全性有所提高.     

超细CL-20/HMX共晶的制备、表征及其与推进剂组分的相容性

通过加入微量溶剂,采用超高效混合技术,在70 g的加速度条件下反应30 min制备得到摩尔比为2∶1的超细六硝基六氮杂异伍兹烷与奥克托今(CL-20/HMX)共晶,通过X射线粉末衍射、差示扫描量热法鉴定了CL-20/HMX共晶的形成,并对其形貌、粒度、感度等进行了表征测试。结果表明:制备的超细CL-20/HMX共晶纯度为92.6%,共晶炸药呈规则块状、表面光滑、粒径小于1μm、粒度分布均匀,其X射线衍射图在11.558°,13.264°,18.601°,24.474°,33.785°,36.269°处出现新的较强的衍射峰。超细CL-20/HMX共晶放热分解过程中只有一个放热分解峰,其放热峰温为248.3℃,其分解放热量(2192.1 J·g^-1),显著高于相同摩尔比的物理混合物(1327.3 J·g^-1)。按照GJB772A-1997《炸药试验方法》测得的摩擦感度比原料CL-20降低了16%,特性落高比原料CL-20提高28.6 cm,比原料HMX提高11.5 cm,形成共晶后安全性能更高。采用DSC法研究了超细CL-20/HMX共晶与推进剂常用组分均聚叠氮缩水甘油醚(HGAP)、硝化甘油/1,2,4-丁三醇三硝酸酯混合物(NG/BTTN)、缩二脲三异氰酸酯(N-100)、高氯酸铵(AP)、铝粉(Al)的相容性,发现超细CL-20/HMX共晶与NG/BTTN、AP、Al的相容性较好,与HGAP、N-100不相容。     

HMX/FOX-7共晶炸药分子动力学模拟

基于环四甲撑四硝胺(HMX)主要生长面和共晶形成氢键规则,搭建6种HMX/1基于环四甲撑四硝胺(HMX)主要生长面和共晶形成氢键规则,搭建6种HMX/11-二氨基22-二硝基乙烯(FOX-7)共晶模型。采用分子动力学(MD)模拟研究HMX/FOX-7共晶炸药形成的可能性。MD模拟过程中键长、键角、二面角发生严重扭曲。径向分布函数（RDF）考察HMX中氧原子和FOX-7中氢原子或HMX中氢原子和FOX-7中氧原子间的作用力。发现HMX和FOX-7分子间存在较强氢键和范德华力作用。根据最终HMX/FOX-7结构模型,进行结合能和X-射线粉末衍射（XRD）图谱计算。结果表明：6种共晶模型的结合能大小顺序为：E_b(0 2 0)>E_b(1 0 0)>E_b(随机)>E_b(111 )>E_b(102 )>E_b(0 11). 6种共晶模型的XRD衍射峰与纯组分HMX或FOX-7有很大区别。基于晶体生长形貌,结合能和径向分布函数的研究,FOX-7取代HMX（111 ）晶面的共晶模型易于形成。     

CL-20/1,4-DNI共晶形成的热力学

为了获得共晶形成的热力学判据,为结晶溶剂和过程参数的筛选和优化提供理论指导,开展了六硝基六氮杂异戊兹烷(CL-20)/1,4-二硝基咪唑(1,4-DNI)共晶形成的热力学研究。分别以丙酮、乙酸乙酯和甲醇为结晶溶剂,采用高效液相色谱(HPLC)测定了CL-20和1,4-DNI在纯溶剂的溶解度,以及CL-20在不同浓度(0.04,0.06,0.08,0.10,0.12,0.16,0.20,0.24 g·mL~(-1))1,4-DNI溶液中的溶解度,绘制得到CL-20/1,4-DNI/溶剂三元相图;基于溶液化学中的平衡理论,通过对溶解度数据的拟合,计算得到共晶的溶度积Ksp、络合常数K11及反应自由能ΔG0等热力学参数。结果表明,共晶组分在溶剂中的溶解度越大且组分间溶解度差异越小,其三元相图中的共晶区域越大、形状越对称。三种溶剂中共晶区域由大到小的顺序为:丙酮乙酸乙酯甲醇,且在丙酮和乙酸乙酯中共晶区域形状更对称;热力学参数的计算结果显示,在三种溶剂中,丙酮最有利于CL-20/1,4-DNI共晶的形成,其次是乙酸乙酯;不同温度下丙酮溶剂中的三元相图和热力学参数表明,降低结晶温度有利于CL-20/1,4-DNI共晶的析出。     

原位红外漫反射光谱研究HMX的分解动力学

采用原位红外漫反射光谱研究了炸药1,3,5,7-四硝基-1,3,5,7-四氮杂环辛烷(HMX)的热分解动力学.结果表明升温中HMX会发生C-N键和N-N键的断裂,释放出CO2、N2O、CO、NO、HCHO、HONO、NO2和HCN八种气体,HMX的分解动力学方程为kC.N=e34.6exp(-152/RT).     

CL-20/HMX共晶THz光谱的理论研究

通过共晶的方式来改善炸药的性能已成为含能材料领域的研究热点,共晶炸药的形成主要依赖异相分子间相互作用,而这些相互作用的能级跃迁正好位于太赫兹(THz)谱的检测范围。以六硝基六氮杂异伍兹烷(CL-20)/环四亚甲基四硝胺(HMX)共晶作为模型体系,采用分子动力学与量子力学相结合的方法,对共晶组分HMX和CL-20以及CL-20/HMX共晶的THz光谱进行了理论研究,对特征峰进行了振动模式的指认和分析,确认了不同分子间相互作用在THz谱上的响应。结果表明,与共晶单体CL-20和HMX相比,CL-20/HMX共晶出现了新的特征吸收峰,分别位于0.23,0.49,1.1,1.47,1.73,2.27 THz处。其中,1.1,1.47,1.73 THz处的吸收峰均由分子间C—H…O氢键引起,而1.73 THz处的吸收峰主要指配为异相分子间氢键。     

氧化高氮杂环羟胺盐在固体推进剂中的能量性能分析

为评价新的氧化高氮杂环羟铵盐作为复合固体推进剂组分的能量潜力,采用推进剂性能评估程序PEP模拟计算了3,3'-二硝基-5,5'-联-(1-氧-1,2,4-三唑)二羟铵(DHDNBT)、5,5'-联-1,1'-二氧-四唑二羟铵(TKX-50)和5,5'-偶氮联-(1-氧四唑)二羟铵(DHABT)取代AP/Al/HTPB和AP/Al/GAP+NE两种复合固体推进剂体系中AP后的能量效果,并与HMX进行了比较。结果显示,在高固体含量的AP/Al/HTPB体系中,TKX-50和DHABT取代部分AP所得到的配方在很大的配方调节范围内能量性能与HMX取代AP配方相当,DHDNBT取代AP所得配方能量特性与同样含量HMX取代AP所得配方相当。在AP/Al/GAP+NE体系中,DHDNBT配方能量性能与同样含量HMX配方相同。含TKX-50和DHABT配方能量性能优于含HMX配方。含TKX-50和DHABT配方最高冻结流比冲分别为2662.7 N·s·kg-1和2696.0 N·s·kg-1,比HMX取代同体系中AP所得配方的最高冻结流比冲(2622.5N·s·kg-1)高40.2 N·s·kg-1(TKX-50)和73.5 N·s·kg-1(DHABT)。用设想的双-(1-氧-四唑)胺二羟铵(DHBTA)取代AP/Al/GAP+NE体系中AP可使最高冻结流比冲达到2708.7 N·s·kg-1,比HMX取代同体系中AP所得的最高冻结流比冲高86.2 N·s·kg-1,且在很大配方调节范围内有比HMX配方更高的能量特性。     

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.     

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.     

Design and Analysis of Test Schemes of Static Postponing Time on Shrapnels Used to Riot Control

The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and three kinds of pressures,the consumed ammunitions are more excessive. Statistic analysis and tentative checkout about a lot of test data are done,feasibility gists are put forward for optimizing of the test design scheme. The optimizing design and data analysis of test scheme of the item are done by managing uniformity design theory, two scientific and reasonable six-point test schemes are confirmed. The feasibility and reliability of the optimizing design schemes put forward above are proved ulteriorly by test validating. The gained schemes not only have good design uniformity and little ammunition wastage and meet the test demand, but also have better forecast ability for the result data of other points using the mathematic models from the actual test points.     

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.     

Design and Simulation of TF and TA Controller for Missile

A nonlinear terrain following(TF) and terrain avoidance(TA) controller is proposed for missile control systems. Based on classical TF algorithm (adaptive angle method), a new method for TF controller is proposed by using angle of attack. A method of obtaining terrain outline data from digital elevation map (DEM) for TF control is discussed in order to save store space. A TA algorithm is proposed by using bank-to-turn technique. The block control model, which is suitable for backstepping design, is given for nonlinear model of missile. Making full use of the characteristics of the system and combining block control principle and backstepping technique, a robust controller design method is proposed. Uncertainties in every sub-block are allowed, and can be canceled by using the idea of nonlinear damping. It is proved that the state tracking errors are converged to a neighborhood of the origin exponentially. Finally, nonlinear six-degree-of-freedom simulation results for the missile model are presented to demonstrate the effectiveness of the proposed control law.     

Design of Non-fragile Satisfactory Estimator for Linear Continuous Perturbed Stochastic Systems

The design problem of non-fragile estimator is addressed for a class of perturbed linear continuous systems. The perturbations occur on the plant and estimator parameters. The estimator designed should force the error system to achieve the desired decay rate and force the steady error variance less than the specified upper bound irrdevancy of the admissible plant perturbations and estimator perturbations. Consistency problem of the decay rate with the variance upper bound is first considered via linear matrix inequality （LMI） approach. The solution of the estimator parameter under specifications to be consistent is then discussed. The consistency condition of specifications and estimator parameter solution are transformed to feasible or minimum problems subject to a set of LMI respectively. The method is illustrated by a numerical example.     

An Improved Scene-based Nonuniformity Correction Algorithm for Infrared Focal Plane Arrays Using Neural Networks

The improved scene-based adaptive nonuniformity correction （NUC） algorithms using a neural network （NNT） approach for infrared image sequences are presented and analyzed. The retlna-like neural networks using steepest descent model was the first proposed infrared focal plane arrays （IRFPA） nonuniformity compensation method, which can perform parameter estimation of the sensors over time on a frame by frame basis. To increase the strength and the robustness of the NNT algorithm and to avoid the presence of ghosting artifacts, some optimization techniques, including momentum term, regularization factor and adaptive learning rate, were executed in the parameter learning process. In this paper, the local median filtering result of Xij （ n ） is proposed as an alternative value of desired network output of neuron Xij （ n ）, denoted as Tij （ n ）, which is the local spatial average of Xij （ n ） in traditional NNT methods. Noticeably, the NUC algorithm is inter-frame adaptive in nature and does not rely on any statistical assumptions on the scene data in the image sequence. Applications of this algorithm to the simulated video sequences and real infrared data taken with PV320 show that the correction results of image sequence are better than that of using original NNT approach, especially for the short-time image sequences （several hundred frames） subjected to the dense impulse noises with a number of dead or saturated pixels.     

Piecewise Filter of Infrared Image Based on Moment Theory

The disadvantages of IR images mostly include high noise, blurry edge and so on. The characteristics make the existent smoothing methods ineffective in preserving edge, To solve this problem, a piecewise moment filter （PMF） is put forward. By using moment and piecewise linear theory, the filter can preserve edge. Based on the statistical model of random noise, a related-coefficient method is presented to estimate the variance of noise. The edge region and model are then detected by the estimated variance. The expectation of first-order derivatives is used in getting the reliable offset of edge. At last, a fast moment filter of double-stair edge model is used to gain the piecewise smoothing results and reduce the calculation. The experimental result shows that the new method has a better capability than other methods in suppressing noise and preserving edge.     

Bistatic Sonar Localization Based on Best Linear Unbiased Estimation

A best linear unbiased estimation （BLUE） algorithm for bistatic sonar localization is proposed. The Cramer-Rao bound for bistatic Sonar and the geometrical dilution of precision （GDOP） in different conditions are given. The simulation results show that the location accuracy of BLUE algorithm is higher than the weighted least square method.     

Research on Gear-broken Fault Diagnosis in a Tank Gearbox

A fault diagnosis method of working position gear in a tank gearbox is put forward based on simulating the fault of working position gear in an actual tank, extracting the envelope of vibration signal by Hilbert transformation amplitude demodulation method, and zooming the low-frequency band to envelope signal.