液相化学法制备纳米铝粉及其表征

为了得到微结构可控的纳米铝粉,尝试用液相化学法制备纳米铝粉,并采用X射线衍射(XRD)仪、场发射扫描电子显微镜(FESEM)和能谱仪(EDS)对其进行表征。研究了原料摩尔比、催化剂用量和分解温度对铝粉形貌、粒径和组成的影响。在此基础上,优化出最佳制备工艺参数,当AlCl₃∶LiAlH₄摩尔比为1∶6,催化剂用量为0.04 mL,分解温度为110 ℃时,制得的纳米铝粉为类球形,平均粒径约为50 nm,杂质Cl、Ti含量少。     

纳米铝热剂Al/CuO的制备及性能

采用溶胶-凝胶法及超临界干燥技术,以聚丙烯酸(PAA)作为分散剂,1,2-环氧丙烷作为Cu(Ⅱ)离子水解促进剂制备了CuO气凝胶,并在温和、无毒的条件下制备了纳米铝热剂Al/CuO。采用比表面测试法(BET)、扫描电子显微镜(SEM)、X射线能谱仪(EDS)、X射线衍射(XRD)、差热分析法(DTA)-差示扫描量热法(DSC)等方法对样品的结构和热反应特性进行表征。结果表明,纳米Al粒子与CuO气凝胶粒子均匀复合,形成Al/CuO。纳米铝热剂Al/CuO的反应放热峰分别出现在598℃和752℃左右,快速燃烧过程伴随明亮火焰。     

NC/Al纳米复合含能材料的制备与表征

采用溶胶-凝胶法和超临界二氧化碳干燥法制备了硝化棉/铝粉(NC/Al)纳米复合材料,并通过红外光谱、比表面积、扫描电子显微镜(SEM)以及差示扫描量热(DSC)等分析方法对复合材料进行了表征。研究结果表明: 纳米铝粉与NC气凝胶骨架成功复合; 复合材料为平均孔径在20~50 nm之间的介孔材料,纳米铝粉在凝胶中均匀分散; NC/Al纳米复合材料的比表面积随铝粉添加量增加而下降; 复合材料中纳米铝粉与硝化棉质量比为5∶10时, NC组分分解热由空白NC气凝胶的1689.21 J·g-1提高至2408.07 J·g-1。      

粒径大小对高频感应加热制备纳米铝粉活性影响

采用高频感应加热蒸发-冷凝法制备了20,25,50 nm三种不同粒度的纳米铝粉,并运用X射线衍射(XRD)和透射电镜(TEM)对纳米铝粉进行表征,使用差热分析(DTA)研究了不同粒径纳米铝粉的热学行为。结果发现,随着纳米粒子粒径从50 nm减小到20 nm,纳米铝粉反应放热热焓从3.721 kJ.g-1减少到0.928 kJ.g-1,即随着粒径的减小纳米铝粉的活性反而变低。认为这是由于铝纳米粒子表面氧化铝膜含量的增加,采用高频感应加热方法制备的粒子不存在内部储能所致。因此,纳米铝粉的活性,不仅取决于粒子的尺寸大小,还取决于粒子的制备方法,以及粒子表面包覆壳层的种类、结构、厚度等。     

喷雾干燥前驱体纳米Al悬浮液的制备及分散稳定性

为制备具有良好分散稳定性的喷雾干燥前驱体纳米Al悬浮液,采用机械搅拌和超声分散两种分散方法制备了纳米Al悬浮液,研究了纳米Al粉在主炸药黑索今(RDX)溶液中的分散稳定性。利用紫外可见分光光度计研究了分散速度、分散时间、超声时间、悬浮液质量浓度、分散温度、纳米铝粉的粒径等对悬浮液分散稳定性的影响,采用扫描电子显微镜(SEM)分析了喷雾干燥后样品的形貌。结果表明:选择粒径为50～100 nm的铝粉,当分散速度为400 r·min~(-1),分散时间为30 min,超声时间为3～10 min,悬浮液质量浓度为1%,分散温度为25℃时,悬浮液的吸光度值最大,分散稳定性达到最佳。     

纳米碳酸锶/高氯酸铵复合粒子的制备及其撞击感度和热分解性能研究

利用超声辅助共沉淀法制备纳米碳酸锶（SrCO₃）,通过溶剂-非溶剂法制备纳米碳酸锶/高氯酸铵（SrCO₃/AP）复合粒子。采用透射电子显微镜、扫描电子显微镜、X射线粉末衍射仪(XRD)分别对纳米SrCO₃的形貌、粒径、晶型和纳米SrCO₃/AP复合粒子的复合效果进行表征。对纯AP和纳米SrCO₃含量分别为2%、4%、6%的SrCO₃/AP复合粒子进行撞击感度测试;采用差示扫描量热仪分别对纯AP、纳米SrCO₃/AP复合粒子和相同比例的纳米SrCO₃与AP的简单混合物进行热分析。通过马弗炉将纳米SrCO₃/AP复合粒子分别在350 ℃和500 ℃下煅烧1 h,对煅烧后的产物作XRD表征,研究纳米SrCO₃的作用机理。结果表明：采用超声辅助共沉淀法制备出的纳米SrCO₃为类球形,粒径在60 nm左右,晶型为斜方晶系;制备出的纳米SrCO₃/AP复合粒子中,微米级的AP表面均匀分布着纳米SrCO₃,纳米SrCO₃的加入会使AP的撞击感度增加;通过两种不同方式添加的纳米SrCO₃均能升高AP的高温分解峰温度,对AP的低温分解没有影响;与纳米SrCO₃和AP的简单混合物相比,纳米SrCO₃/AP复合粒子中AP的高温分解峰值温度升高6.02 ℃,将纳米SrCO₃与AP进行复合后可以提高纳米SrCO₃对AP高温分解的负催化作用。     

自组装磁性微囊的合成与制备

以聚丙烯酰胺 (PAM) 为表面活性剂,采用一步水热法合成了超顺磁性Fe₃O₄纳米粒子,并且在改变PAM用量的条件下合成了囊状的磁性材料。通过X射线衍射(XRD)、扫描电子显微镜 (SEM)、振动样品磁强计等对磁性Fe₃O₄的结构、形貌、磁性进行表征。结果表明,磁性微囊外径约为200 nm,组成微囊的Fe₃O₄纳米粒子其粒径分布在30 nm左右,磁性微囊的饱和磁化强度为62.5 emu/g,表现出超顺磁性。     

纳米Al粉的结构和性能表征

采用自悬浮定向流法制备金属纳米A l粉。用透射电镜(TEM)、X射线能量色散谱(EDAX)、X射线衍射(XRD)、紫外-可见光吸收光谱(UV-V is)和差示扫描量热-热重法(DSC-TG)对纳米微晶形貌、粒度、结构和性能进行了研究。结果表明:纳米A l粉的平均粒径为50 nm,颗粒基本为球形,放置半年后含氧量为8.2%,最大的吸收峰出现在波长为253 nm处。在Ar气流中,在780℃时纳米铝粉增重约20%,熔化峰位置为654.8℃,熔化吸热为136 J.g-1。     

CNTs负载Fe2O3的制备及催化氧化剂的热分解研究

采用液相沉淀法制备了沉积于碳纳米管(CNTs)表面的Fe2O3纳米粒子(CNTs/Fe2O3),用透射电子显微镜(TEM)、光电子能谱仪(XPS)和X射线衍射仪(XRD)对其进行了表征。研究了CNTs/Fe2O3纳米粒子对高氯酸铵(AP)、二硝酰胺铵(ADN)和硝酸铵(AN)的催化热分解。结果表明,CNTs表面上均匀地负载了平均粒径为22nm的α-Fe2O3。添加了1%、3%和5%CNTs/Fe2O3纳米粒子的AP的初始分解温度分别降低了33.7,40,50.8℃,热分解峰温分别降低了14.7,22.9,26.4℃。添加1%CNTs/Fe2O3纳米粒子的ADN和AN的初始分解温度分别降低了12.1,3.6℃,热分解峰温分别降低了18.6,6.6℃。     

机械粉碎法制备纳米CuCr2O4及其对高氯酸铵热分解性能的影响

采用HLG-5型纳米化粉碎机批量制备了粒径约为60 nm的纳米CuCr₂O₄. 通过X射线衍射仪（XRD）、透射电子显微镜（TEM）对样品的结构及形貌进行表征,并采用差示扫描量热仪（DSC）分别研究工业CuCr₂O₄、共沉淀法制备的纳米CuCr₂O₄及机械粉碎法制备的纳米CuCr₂O₄对高氯酸铵（AP）热分解性能的影响。结果表明,与前二者相比,机械粉碎法制备的纳米CuCr₂O₄对AP具有更好的催化性能,能够使其速率常数提高,高温分解活化能减小。这将促进纳米CuCr₂O₄作为燃速催化剂在AP基复合推进剂中的应用。     

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.     

Method for Measuring Velocity of Warhead Fragments Based on Photoelectric Detection

For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further.     

数码电子雷管中影响点火头性能因素分析

阐述了数码电子雷管中,点火药剂细结晶三硝基间苯二酚铅（LTNR）的制备工艺;从点火药剂的种类、加入黏合剂的质量分数、桥丝直径、点火头的电阻值、防潮漆的蘸涂等方面对点火头性能的影响因素进行了探讨;通过震动试验、并联起爆试验、延期精度检测与考核,试验结果表明：一次性合成的细结晶LTNR是制造数码电子雷管点火头较为理想的点火药剂,按技术要求生产的点火头性能指标能够满足行业标准要求。     

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.