五唑钠的制备工艺及C─N键切断机理

以2,6?二甲基?4?五唑基苯酚钠盐为原料,间氯过氧苯甲酸(m?CPBA)与甘氨酸亚铁(Fe(Gly)_2)为氧化切断试剂和稳定催化剂,在低温条件下成功合成了五唑钠;探索了芳基五唑氧化切断C—N键的反应条件:芳基五唑、Fe(Gly)2与m?CPBA摩尔比为1∶3∶4.5,反应时间24 h,反应温度-45℃,粗品收率为28%;探索了不同氧化切割试剂对五唑钠产率的影响,并分析了五唑钠产率低的原因;利用X?射线单晶衍射仪(X?ray single crystal diffractometer,XRD)、核磁(~(15)N NMR和~1H NMR)、元素分析、红外、质谱等对五唑钠和芳基五唑切断副产物(2,6?二甲基对苯醌)的结构进行了表征;并在此基础上推测分析了m?CPBA与Fe(Gly)_2氧化切断芳基五唑C—N键的机理历程。     

五唑金属盐分离纯化方法

为解决五唑金属盐合成中分离纯化困难等问题,以芳基五唑C—N切断反应后处理所得五唑钠水溶液为研究对象,采用沉淀法对五唑金属盐进行了分离纯化研究。结果表明,五唑钠水溶液中含有大量有机酸盐,以及硝酸钠、氯化钠等无机盐杂质。与N5负离子相比,有机酸根更易与金属离子形成沉淀,从而影响五唑金属盐析出。将五唑钠水溶液调节为酸性,萃取除去有机酸盐后加入氯化钴,成功沉淀得到五唑钴金属盐。研究发现,pH值越低,有机酸盐的去除效率越高,五唑钴纯度越好。确定了五唑钴的适宜分离纯化条件：pH值为3,氯化钴与原料4-氨基-2,6-二甲基苯酚（1）的摩尔比为0.26∶1。离子色谱表明,所得五唑钴经简单重结晶后纯度高达97.9%。在此基础之上,研究了沉淀法对其它五唑金属盐的适用性。结果表明,沉淀法亦适用于五唑铁、五唑亚铁和五唑铜等金属盐的分离纯化。     

三种低熔点二异噁唑含能化合物的合成与表征

为研究二异噁唑含能化合物的合成及性能,以二氯乙二肟、炔醇和炔溴为原料,经过[3+2]环化反应、硝化和叠氮化反应合成得到三种低熔点含能化合物:5,5′-二叠氮甲基-3,3′-二异噁唑(2)、3,3′-二异噁唑-5,5′-二亚甲基硝酸酯(4)和3,3′-二异噁唑-4,4′,5,5′-四亚甲基硝酸酯(6),总收率分别为66%,67%和64%。利用红外、核磁和元素分析对目标化合物和中间体进行了结构表征;探讨了—C+=N—O-和C≡C经1,3-偶极环加成反应构建二异噁唑的反应机理。利用DSC和TG研究了化合物(2)、(4)和(6)的热行为。化合物(2)、(4)和(6)的熔点分别为77.46,95.18℃和124.36℃,热分解起始温度分别为179.21,165.34℃和168.69℃。     

5,5′-(2-三氟甲基)-咪唑-4,5-二(1H-四唑)及其含能离子盐的合成与表征

以二氨基马来腈为原料,经过与三氟乙酸酐缩合、环化,与叠氮化纳再次缩合,合成得到了新型含能化合物5,5'-(2-三氟甲基)-咪唑-4,5-二(1H-四唑),收率61.3%;基于该化合物的酸性,设计合成了2种含能离子盐5,5'-(2-三氟甲基)-咪唑-4,5-二(1H-四唑)的羟胺盐和胍盐。利用红外光谱、核磁共振和元素分析对中间体及产物结构进行了表征。探讨了生成5,5'-(2-三氟甲基)-咪唑-4,5-二(1H-四唑)过程中影响四唑环化反应的关键因素,确定的最佳反应条件为:反应介质为水,n(2-三氟甲基-4,5-二氰基咪唑)∶n(Na N3)=1∶2.4,反应温度98℃,反应时间4 h。收率最高达86.3%。通过DSC-TG研究了5,5'-(2-三氟甲基)-咪唑-4,5-二(1H-四唑)的热分解性能,热分解曲线表明化合物直到223.65℃才开始分解,整个分解过程经历了两个主要的放热分解阶段和热失重阶段,最大放热峰温度为285.78℃,说明该化合物结构比较稳定。     

3,4-二(吡嗪-2′-基)氧化呋咱的合成及热分解机理

以自制的2-偕氯肟基吡嗪为原料,经分子间二聚环化反应合成了具有对称取代结构的氧化呋咱化合物——3,4-二(吡嗪-2'-基)氧化呋咱(BPF);利用红外光谱、核磁共振(1H NMR、13C NMR)、元素分析及质谱等分析表征手段确定了目标化合物BPF的结构;初步探讨了分子间二聚环化反应机理;优化了二聚环化反应的合成工艺条件;利用差示扫描量热(DSC)、热重分析(TG-DTG)等方法研究了目标化合物BPF的热分解机理。结果表明,二聚环化反应的较佳工艺条件为:以乙醚为反应溶剂,质量分数为3%的Na2CO3水溶液为缚酸催化剂,Na_2CO_3加入摩尔量为理论量的1.10倍,在2~10℃反应4 h,收率为75.6%;热分解机理结果显示,目标化合物BPF的热分解首先发生在氧化呋咱环中N—O键的开裂。     

对羟基苯基五唑及其衍生物的合成与稳定性

以对氨基苯酚及其衍生物为原料,在-45℃下合成了一系列芳基五唑,通过核磁和质谱分析对其结构进行了表征。研究了取代基的位置及数目对芳基五唑化合物稳定性的影响,运用电喷雾离子化串联质谱分析了不同裂解能量下(10,60 e V)芳基五唑的裂解途径,并讨论了芳基五唑的稳定性与产生N~-_5之间的关系。结果表明,在这一系列化合物中,间位和对位被供电基取代的3,5-二甲基-4-羟基苯基五唑稳定性最好,同时在高裂解能量(60 e V)轰击下切断C—N键产生N~-_5的能力也最强。     

直链取代五唑共价化合物的稳定性和热解机理理论研究

五唑离子化合物是当前新型含能材料的一个研究热点,其制备通常以五唑共价化合物为前体实现.多数情况下,五唑共价化合物的稳定性对能否成功制备五唑离子化合物有很大影响.采用密度泛函理论B3LYP/6-31G**方法重点研究了18个直链取代五唑共价化合物(R—N5或N5—R—N5)的侧链化学键的解离能EBD和N5环的分解能垒Ea,分析了侧链对其稳定性和热解机理的影响.发现当R为羟基或氨基时,侧链容易断裂,N5环也容易破裂,难以得到N5-;当R为烷基时,N5环裂解的Ea相对较大,更可能得到N5-,且侧链C—N键和N5环的稳定性受烷基链长短影响不大;在双环分子中,两个N5环的裂解是先后发生的,后一个环的裂解能垒比前者高,裂解生成氮气和叠氮化物;分子侧链上的C—C键会先于C—N键断裂,从而可能使C—N键的EBD明显降低而对N5环的Ea影响不大,因此,在由五唑共价化合物制备五唑盐的过程中,先切断C—C键可能更利于得到N5-.     

甲醇溶液中五氮唑负离子的制备与表征

以对氨基苯磺酸为起始原料,通过重氮化、缩合和水解反应,合成了3,5-二甲基-4-羟基苯胺盐酸盐,总收率为75%。用3,5-二甲基-4-羟基苯胺盐酸盐制备了-50℃下稳定的3,5-二甲基-4-羟基苯基五唑,收率为66.7%。以甲醇为溶剂,亚铁盐为还原剂,间氯过氧苯甲酸为氧化剂,可切断3,5-二甲基-4-羟基苯基五唑分子中的C—N键,得到少量的五唑负离子,并通过质谱、核磁等方法对其进行表征。同位素标记实验证明五唑环中N原子具有相同的化学环境,说明五唑负离子极有可能具有芳香性。     

1-甲基-3-氨基-5-硝基-1,2,4-三唑的合成新工艺

以甲基肼为原料,与盐酸反应得到盐酸甲基肼,再与二氰二胺在50℃进行缩合环化反应,调节溶液pH值,经重氮化反应合成含能化合物1-甲基-3-氨基-5-硝基-1,2,4-三唑(DNMT),总收率62.3%,纯度99.4%,并用红外光谱、核磁共振、质谱、元素分析等方法表征了其结构。探讨了缩合环化反应工艺条件,确定适宜的反应条件为:溶剂为乙醇,n(C2H3N4)∶n(NH2NHCH3.2HCl)=1∶1.1,pH=8~9,成盐组分是盐酸,重结晶溶剂为丙酮。     

一种Ti3AlC2陶瓷材料的制备方法研究

采用机械球磨和热处理方法制备Ti3Al粉体,并将Ti3Al和C反应烧结制备Ti3AlC2陶瓷材料。将Ti、Al的摩尔比为3∶1的混合粉末,球磨20 h后经750℃热处理40 min得到质量分数达到98.54%的Ti3Al金属间化合物;然后采用Ti3Al和C的摩尔比为1∶2为原料,进行反应烧结制备Ti3AlC2,在1 300℃保温60 min,可得到试样中Ti3AlC2的质量分数为96.4%。研究得出Ti3AlC2的合成路径即在反应过程中先生成Ti2AlC和TiC两相,然后二者反应合成Ti3AlC2相。     

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.