  Mo doped ruthenocuprates Ru1-xMoxSr2Eu1.5Ce0.5Cu2O10 are synthesized for x =
0.0, 0.2, 0.4, 0.6, 0.8 and 1.0, and their magnetic and superconducting
properties are studied. It has been found that the magnetic transition
temperature TZFCpeak, which corresponds to the appearance of weak ferromagnetic
effect, decreases from its value of 75 K for x = 0.0 to 22 K, 25 K and 18 K,
respectively for the x = 0.2, 0.4 and 0.6 samples. Another finding is that the
magnetic susceptibility reduces at TZFCpeak by a factor of about 6, 85 and 413
for x = 0.2, 0.4, and 0.6 respectively. The samples of x = 0.8 and 1.0 are
found to have no magnetic or superconducting effects. The values of the
superconducting transition temperature are obtained from the resistivity versus
temperature data. An important result is that Tc increases by 4.5 K and 7.0 K
for x = 0.2 and 0.4 respectively, and then decreases by 17 K for x = 0.6. The
observed variation of Tc with x has been explained in terms of a theory which
combines the effects of weakening magnetic behavior and reducing carrier
concentration in a phenomenological manner. The resulting theory is found to
provide a good agreement with the observed value of Tc.
