Ir - ta - ti metal oxide coated titanium anodes of variable composition were prepared by thermal decomposition . their micro morphorogies and electrochemical properties were characterized by scanning electron microscope , open circuit potential , cyclic voltammetry , consumption rate measurements and accelerated life test . the sem results indicated that all coatings were of a porous and cracked - mud microstructure influenced greatly by the composition of coatings . the electrochemical measurements showed that the ir - ta - ti ternary oxide - coated anodes exhibited excellent electrochemical activity and electrochemical stability in both acidic media and seawater which were affected by the composition and microstructure of the coatings . owing to good corrosion resistance and low consumption rate in seawater , metal oxde coated anodes belong to insoluble material , and can be potentially applid in impressed current cathodic protection systems as an anode 采用热分解方法在钛基体上制备铱钽钛金属氧化物阳极,用扫描电镜对阳极涂层显微形貌进行分析,通过强化电解寿命试验、开路电位测试、消耗率试验及循环伏安曲线研究了金属氧化物阳极的电化学性能. sem分析结果表明铱钽钛金属氧化物阳极涂层呈现多孔多裂纹形貌结构.随阳极涂层组成不同,涂层显微形貌表现出很大差异,这种差异直接影响阳极电化学性能.电化学性能试验结果表明铱钽钛金属氧化物阳极在酸性介质和海水中具有良好的电化学稳定性和电化学活性.此外,铱钽钛金属氧化物阳极在海水中的消耗率很低,属于不溶性的阳极材料,作为外加电流阴极保护用辅助阳极具有广泛的应用前景
Furthermore , the metallizational film level ' s noises measurement system ( hardware and software ) was designed , the automatic data acquisition and analysis have been realized , noises measurement during accelerated life test , namely electromigration process , have been completed , and a lot of valuable data have been gained 通过加速寿命实验和对样品的噪声测量,获取了样品电迁移过程不同损伤程度的噪声数据。对实验数据和结果做了对比分析,找到了与电迁移相关的噪声表征参量的变化规律。
Moreover , the data processing method of accelerated life test is used to solve the problem of the reliability data conversion under different operating status to liquid rocket engine . and the counter power law model is introduced as the relation model between the characteristic life and the combustion chamber pressure , the accelerated life equation of the constant stress accelerated life test for the weibull distribution is obtained , through the accelerated life equation , the reliability estimate of different combustion chamber pressure is calculated 再次,采用加速寿命试验的数据处理方法对液体火箭发动机不同工况下可靠性数据折算的问题进行了研究,引入逆幂律模型作为特征寿命与燃烧室压力之间的关系模型,得到了weibull分布下恒定应力加速试验的加速寿命方程,并通过加速寿命方程折算出不同室压下的可靠度估计。
In chapter3 , we discuss the multiplicate progressive stresses accelerated life test . under the weibull distribution and an invers power law model we first present a necessary and sufficient condition for the existence and uniqueness of mle for the exponential distribution , then give estimators and confidence intervals of the parameters based on the blue . finally , we study them by using monte - carlo simulation 第三章首先指出了一组序进应力加速寿命试验下weibull分布分布参数的mle不唯一,然后给出了p组序进应力加速寿命试验下指数分布的mle存在和唯一的一个充要条件,并用随机模拟的方法研究比较了参数估计的优良性,最后给出了p组序进应力加速寿命试验下weibull分布中参数的点估计和区间估计,讨论了有关问题,给出模拟实例。