  The effects of Ni substitution on Ce(Cu1-xNix)2Si2 have been studied by
specific heat and electrical resistivity measurements. The specific heat
measurement has revealed that the enhanced quantum fluctuations around an
antiferromagnetic quantum critical point are markedly suppressed by Ni
substitution, and that the Fermi liquid state recovers in the Nirich region (x
> 0.12). The characteristic T-linear dependence of the resistivity has been
observed at approximately x ~ 0.10 together with a sign of superconductivity.
The variation of n in the form of rho - rho0 = aT^n against Tmax^1, at which
the resistivity peaks, coincides with the case of high-pressure experiments on
pure CeCu2Si2. The anomalous T-linear behavior appears to occur in the
crossover region from the Kondo regime to the valence fluctuation regime rather
than in the conventional antiferromagnetic quantum critical region.
