【摘要】 <正> 1 同一电流密度下的电阻特性YBa₂Cu₃O_7-y超导体（Φ10×2.5）采用四引线法测量电阻,电极间隔为1.5m,测量表明,对于名义成份为 YBa₂Cu₃O_7-y,的样品,室温电阻约为5Ω,电阻随温度降低而减小.图1是恒流为20mA 的 R—T 曲线.温度在128k 以上样品呈金属行为;当温度降到128k 时,电更多还原

【Abstract】 This paper reports the transition properties of electrical impedance in th sample of YBa₂Cu₃O_7-ysuperconductor.A new method to define the initial transi tion temperature is given.The measured results show that when the density o electical current varies,the R-T curves of the sample are evidently different unde the temperature of 128 K.更多还原