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Structure and electrical property are studied in the quenched Bi 2 Sr 2 Ca 1-x Nd x Cu 2 O 8 + δ system. The quenched samples with 0≦x≦1 have a single phase of the Bi 2 Sr 2 CaCu 2 O 8 + δ structure, as do the furnace-cooled samples. The oxygen concentration decreases slightly by about 0.05 in the chemical formula upon quenching from 800°C into liquid nitrogen. The T c remains a constant (∼90K) for x≦0.15, and decreases linearly with x in the range of 0.15≦x≦0.45, and superconductivity disappears for x≧0.45. The result for the quenched systems, if x is shifted by +0.1 in it, agrees very well with that for the furnace-cooled Bi 2 Sr 2 Ca 1-x Nd x Cu 2 O 8 + δ and Bi 2 Sr 2-x Nd x CaCu 2 O 8 + δ systems. The relationship between the T c and the hole concentration in [Cu-O] is confirmed to be universal in both the quenched and the furnace-cooled Bi 2 Sr 2 CaCu 2 O 8 + δ systems.

Structure, resistivity and susceptibility have been measured in the Bi2Sr2-x RE x CaCu2O8+δ (RE=Nd and Ce) system. The samples with 0≤x≤1 (RE=Nd) and 0≤x≤0.25 (RE=Ce) have almost single phases of the Bi2Sr2CaCu2O8+δ structure. The x-dependence on T c in the Ce-substituted system is almost twice as strong as that in the Nd-substituted one. The valences of Nd and Ce ions in the samples were determined from susceptibility measurement as trivalent and tetravalent, respectively. The hole concentration was determined from the Hall effect measurement. The results confirm that the hole concentration in the Ce-substituted system becomes twice as strong as that in the Nd-substituted one, as expected from the universal relationship between the T c and the hole concentration in the Bi2Sr2CaCu2O8+δ system.