变形温度和变形程度对Ti－31合金性能和组织的影响

通过高温和室温拉伸试验，研究了变形温度和变形程度对Ｔｉ－３１合金板材性能和组织的影响。结果表明，合金在７５０～８５０℃的温度下变形５％～２０％空冷后，其室温机械性能均能达到材料的技术指标要求。并发现了材料在９００℃的临界变形区。     

Stationary and traveling hot spots in the catalytic combustion of hydrogen in monoliths

In the course of catalytic combustion of hydrogen (1-5% H₂ in air) in monolith reactors, strongly localized stationary and traveling hot spots arise in response to a sudden and persistent rise of gas flow velocity. Such hot spots may occur, e.g. in a catalytic converter following the acceleration of a car or in a catalytic combustor as a result of a load increase. This phenomenon is illustrated by simulations using a two-phase reactor model. The temperature overshoot of the adiabatic limit is typically of the order of the adiabatic temperature rise itself.The following mechanism underlies this behavior. Light fuel is supplied to the catalytic wall by fast diffusion (in the direction perpendicular to flow), while the heat released by reaction is removed from the wall by the slower, mixture-averaged heat conduction. This leads to accumulation of heat at the catalytic surface that eventually saturates at high temperatures. The hot spots may exhibit intricate dynamics, propagating downstream or upstream, or they may remain stationary. The direction of propagation depends on the relative strength of convective downstream and conductive upstream contributions to the overall displacement of reaction fronts. Generally, the hot spot tends to drift downstream at low flow velocities, remain stationary at intermediate flow velocities, and drift upstream at high flow velocities.     

塑钢包装箱材料贮存寿命预测

用热老化箱对4种塑钢包装箱用材进行了为期1个月的热老化试验，以材料的冲击强度作为判据指标，通过回归处理外推得到其常温下的贮存寿命预测评估结果。     

Recovery retardation in equal channel angular pressed Al–Zr alloy during friction stir welding

The effect of Zr on reduction of hardness and microstructure in an FS weld of equal channel angular-pressed Al alloy was investigated. Zr addition to Al suppressed dynamic recovery in the thermomechanically affected zone and enabled retention of the high hardness of the ECA-pressed material throughout the weld.     

TiO_2压敏电阻陶瓷元件等静压成型试验研究

采用干压及干压加等静压两种成型方法,通过对不同样品的电性能和焊接性能的比较,并通过SEM微观形貌的观察,研究了等静压成型对TiO2压敏电阻陶瓷元件的微观结构及电性能的影响。结果表明,经等静压成型的TiO2压敏电阻陶瓷的微观结构比较致密,气孔减少,元件的电压一致性和焊接性能得到较大的改善。     

A new method of characterization for stratified thermal energy stores

A new method for characterization of stratified thermal energy stores (TES) that integrates both the first law and the second law concerns is presented here. The first law concern is incorporated into a quantity called energy response factor and the second law concern into an entropy generation ratio. A product of these two quantities is at the heart of the TES efficiency definitions. This approach removes the overemphasis of the existing methods either on the first or the second law of thermodynamics which often biases the characterization results. The information about the evolution of the temperature field of the system in time is the prerequisite of the new method. It may be obtained from experiments or from suitable numerical simulations. The current method can be easily integrated into computational fluid dynamic (CFD) simulations and thus facilitate CFD-based design analysis. As an example of such CFD-integrated analysis, a large-scale hot water seasonal heat store is numerically studied to identify the effects of aspect ratio, containment shape, internal structures, and containment size on their efficiency. The results suggest the effectiveness of the new method in deriving useful design insights.     

热载流子注入对MOS结构C─V和I─V特性的影响

讨论了热载流子注入对ＭＯＳ结构Ｃ─Ｖ和Ｉ─Ｖ特性的影响。指出热载流子效应引起载流子陷落和界面态的产生，导致Ｃ─Ｖ特性曲线畸变、平带电压漂移和恒定电压下ＳｉＯ２漏电流随时间漂移。本文论述了这些漂移的机理，提出了漂移的ｔｎ物理模型，从而很好地解释了实验所观察到的现象。     

CVD金刚石工具膜生长特征SEM观察

本文用不热形变栅状直丝化学气相沉积（ＣＶＤ）法生长金刚石膜，在Ｓｉ及ＷＣ－Ｃｏ硬质合金衬底上金刚石膜晶面显露规律随衬底温度和甲烷浓度而异，经适当表面处理及选择合适的工艺条件，当生长初期衬底上就呈现出良好晶形的沉积膜，衬底与膜之间的粘结力能得到提高。Ｒａｍａｎ谱分析表明此膜仅具有特征金刚石１３３２ｃｍ￣（－１）峰，通过ＳＥＭ观察揭示出盒刚石膜可在表面、侧面及棱上生长，并与衬底有良好的联结。     

沪芦高速公路软土地基设计与研究

软土地基的处理是影响高等级公路工程质量和使用性能的重要因素 ,针对沪芦高速公路的工程特点 ,通过对不同土层力学性能分析 ,地基稳定验算以及沉降计算提出地基处理方案 ,并介绍通过地基处理后获得的显著效果     

粉末布法制备SiC/Ti基复合材料

用粉末布法制备了低成本SiC/Ti基复合材料.结果表明,采用合适的轧制参数即可容易地获得厚度合适、均匀的粉末布;热失重分析和热解残余物分析指出用来制备粉末布的有机粘结剂的去除过程分成两个阶段,合理除气后,基本没有残余物.使用真空热压工艺制备的SiC/Ti基复合材料,纤维分布基本均匀,纤维与基体的界面结合良好.