No abstract

No abstract

No abstract

The effect of the partial substitution of Cu by Ni in the stabilized 108 K phase was investigated by electrical resistance and a.c. susceptibility measurements. Up to a Ni concentration x = 0.02 the bending of the R (T) curve above T c can be described in the terms of the Lawrence-Doniach theory. The intergrain and intragrain critical transition temperatures decrease to ∆T CG = 9 K and ∆T j = 10.9 K respectively by the Ni substitution in the Cu-O pyramids.