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用变温X 射线衍射 ,扫描量热分析 ,热重分析对精心制作的Bi1 .7Pb0 .3Sr2 Ca2 Cu3Ox 超导样品在后处理前和后处理后从液氮温度到熔点温度进行了分析 ,并对样品进行了XPS分析 ,载流子浓度和超导电性测量 .实验发现 ,样品沿C方向的膨胀系数在低温区有两个反常 ,在高温区有两个热量和重量反常 .结果分析表明 ,这两个反常与晶体结构中两个不同的结构块有关 ,即钙钛矿和盐岩结构块 .实验发现 ,这两个结构块之间的失配 ,超导临界温度 ,样品中的氧含量 ,以及膨胀系数的变化之间有密切的关联 .实验结果表明 ,了解两个不同结构块之间的相互作用对认识高温超导电性有重要作用 .
The prepared Bi1.7Pb0.3Sr2Ca2Cu3Ox superconducting samples were analyzed from liquid nitrogen temperature to melting point before and after the post-treatment by the method of variable temperature X-ray diffraction, scanning calorimetry and thermogravimetric analysis, and the sample Carried out XPS analysis, carrier concentration and superconductivity measurements.Experiments found that the sample along the C direction of the expansion coefficient of two anomalies in the low temperature region, in the high temperature region has two heat and weight anomalies.The results show that these two One anomaly is related to two different structural blocks in the crystal structure, ie, perovskite and salt rock blocks. It was found that the mismatch between these two blocks, the critical temperature of the superconductivity, the oxygen content in the sample, and There is a close relationship between the changes in the coefficients of expansion.The experimental results show that understanding the interaction between two different blocks plays an important role in understanding the HTS properties.