中文摘要：

单一固体材料的电阻率是关于温度的复杂函数。目前尚未见关于相当大的温度范围内恒定电阻率的报道；对恒电阻的需求仍然是通过材料结构组合或电路设计实现的。Cu3NPdx随组份的变化会经历半导体-半金属相变，在Cu3NPd0.238中可以在240K的温度范围内测得不变的电阻率，这一发现至少表明大温区内恒电阻是可以在单一材料内实现的，它对固体物理的理解本身以及诸多应用都有重要的意义。

英文摘要：

Electrical resistivity for individual solids is generally a complicated function of temperature. There has been no report on a constant electrical resistivity in a sizalle temperature range observed in any single solid, and the constant resistance demanded for many applications has been realized only through structure designs or circuits. In the composition-modulated Cu3 NPdx which undergoes semiconducting-to-semimetallic transition, a nearly vanishing temperature coefficient of resistance was measured in a temperature range over 240 K in Cu3NPd0.238. This, to the least, demonstrates the possibility of constant resistivity in a single solid, thus is of significance for both the understanding of solid-state physics and applications.