镁合金在空空导弹导引头上应用可行性研究

对空空导弹导引头上镁合金材料的选用、加工、表面处理、结构装配、盐雾试验等方面进行了研究。首先在目前应用较为广泛的镁合金材料牌号中选取了适合导引头结构应用的MB15来代替目前应用的铝合金材料,并选取导引头中具有代表性的薄壁、高精度试验件进行了加工试制;其次对试制试验件选取不同的表面处理方法进行表面处理,通过装配、盐雾试验来验证其表面处理的防腐蚀能力;最后给出了在空空导弹导引头上应用镁合金的合理建议。     

Assessing the feasibility of involving gaseous products resulting from physicochemical oxidation of human liquid and solid wastes in the cycling of a bio-technical life support system

The study addresses the possible ways of involving gaseous products produced by “wet” incineration of human wastes mixed with H₂O₂ in an alternating electric field in the cycling of the physical model of a bio-technical life support system (BTLSS). The resulting gas mixture contains CO₂ and O₂, which are easily involved in the cycling in the closed ecosystem, and NH₃, which is unacceptable in the atmosphere of the BTLSS. NH₃ fixation has been proposed, which is followed by nitrification and involvement of the resulting products in the mass exchange of the closed system. Experiments have been performed to show that plants can be grown in the atmosphere resulting from the closing of the gas loop that includes a physicochemical installation and a growth chamber with plants representing the phototrophic compartment of the BTLSS. The results of the study suggest the conclusion that the proposed method of organic waste oxidation can be a useful tool in creating a physical model of a closed-loop integrated BTLSS.     

高温合金K38G微晶涂层氧化动力学研究

研究了溅射微晶涂层对K38G在800℃和900℃空气中氧化动力学的影响。发现微晶化后K38G的氧化动力学与经典的抛物线规律存在负偏差。分析认为,微晶化后氧化物形核率大大提高,氧化膜中的扩散由晶格扩散变为晶界短路扩散为主,从而改变了氧化膜的生长动力学。根据Wagner高温氧化的基本理论,对微晶合金高温氧化动力学规律进行了探讨,导出微晶K38G合金氧化动力学遵循四次方规律,即x4=kPt。     

我国商业银行拆入资金业务内部控制体系研究

资金拆入是指商业银行因资金周转需要而在金融机构之间借入资金的行为，是商业银行的一项常规性业务，拆入资金业务内部控制是我国商业银行内部控制体系中的一个重要组成部分。拆入资金业务内部控制体系可以为我国商业银行加强拆入资金业务管理、提高拆入资金业务的运作效率提供可靠的理论借鉴。我国商业银行拆入资金业务内部控制体系的设计必须密切联系我国商业银行拆入资金业务的运作实践。因子分析可以为理论模型提供现实性检验，从而展现我国商业银行拆入资金业务内部控制的现实性微观机理。     

Morphology and Frictional Characteristics Under Electrical Currents of Al203/Cu Composites Prepared by Internal Oxidation

Two AhO3/Cu composites containing 0.24 wt.% A1203 and 0.60 wt.% A1203 separately are prepared by internal oxidation.Effectsof sliding speed and pressure on the fi-ictional characteristics of the composites and copper against brass are investigated and compared.The changes in morphology of the sliding surface and subsurface are examined with scanning electron microscope (SEM) and energy dispersive X-ray spectrum (EDS).The results show that the wear resistance of the AI203/Cu composites is superior to that of copperunder the same conditions.Under a given electrical current,the wear rate of AI203/Cu composites decreases as the AleO3-content increases.However,the wear rates of the Al203/Cu composites and copper increase as the sliding speed and pressure increase under drysliding condition.The main wear mechanisms for AleO3/Cu composites are of abrasion and adhesion;for copper,it is adhesion,although wear by oxidation and electrical erosion can also be observed as the speed and pressure rise.     

吸气式高超声速飞行器内外流同时测力试验

为研究吸气式高超声速飞行器新型测力试验技术的可行性,在马赫数Ma=6、高度H=27km模拟飞行环境下开展了风洞试验。以轴对称吸气式高超声速飞行器无舵翼简化构型为研究对象,通过合理的试验系统设计解决内外流解耦关键技术,采用两个环式六分量天平在同一车次上测量模型内外流气动力载荷。试验结果表明:内外流气动力天平测量数据和全模气动力数据准确反映了内外流解耦、内外流窜流、进气道起动/不起动以及溢流影响等物理现象;从物理上实现了内外流解耦;内流气动力对全机气动性能贡献大;内外流解耦、进气道起动时,气动力数据准确、重复性好;窜流产生的传力属于内力。试验证明,同时测力试验技术可行,为解决内外流气动数据源于不同试验所致的不确定性问题提供了有效手段。     

时滞系统内模控制器参数整定方法研究

针对内模原理对时滞系统控制的局限性,利用一阶泰勒级数逼近模型的时 滞部分, 推导了工业上常见的一阶时滞和二阶时滞模型的内模控制参数表达式, 结合 ITAE 指标和系统鲁棒性设计了新的目标函数, 通过对目标函数的寻优实现了内模控制 器参数的整定。仿真结果表明,该方法具有较好的动态跟踪性能、较强的抗干扰性和鲁 棒性,具有一定的工程应用价值。     

飞机静力试验中机翼的载荷分配研究

针对飞机静力试验加载的问题,为使得试验加载力反映飞机受力特性,由载荷分配前输入的典型剖面上剪力、弯矩、扭矩推导出相邻剖面之间的剪力、弯矩、扭矩,通过构造带内力约束的拉格朗日极值函数求出试验加载力,将载荷分配前输入的内力与试验载荷分配后产生的内力进行对比分析,可以得出:通过构造带内力约束的拉格拉日极值函数法分配得到的试验载荷符合载荷的传递,能够满足飞机静力试验加载的要求,可以用于飞机静力试验的加载。     

TEMPERATURE EFFECT ON OXIDATION PROTECTION LIFE OF MULTI-LAYER COATING FOR C/C COMPOSITES

Carbon-carboncomposites(C/C)exhibitexcellentstructuralpropertiesabove165OC,andareconsideredasthemostpromisingcandidatematerialsforthehighthrust-weightratioturbineengines.Asakeytechnologyforthehigh-temperaturestructuralapplicationsofC/C,oxidationprotectionispaidmoreandmoreattentionrecently.TheoxidationprotectionllfeofacoatedC/Cisdeterminedbyenvironmenta1temperature,becauseitnotonlydecidesthether-mochemicalconditionsofinterfacesinacoating,butalsocontrolsthedynamicprocessofoxy-gendiffusion.The…     

基于改进IRN网络的航空发动机故障诊断

建立了一种带偏差单元的内部回归神经网络.该网络的主要特点是记忆特性好,收敛速度快、稳定性强.介绍了该神经网络在航空发动机故障诊断中的应用方法,并通过实例验证了该方法在发动机故障分类中的实用性.在对某型航空发动机故障诊断中,准确性极高.从而在适时与视情维修过程中提出合理的建议,以便为相应维修方法的实施、改进和研究应用提供可靠的依据,有着良好的推广应用前景.