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Two kinds of Nd1+xBa2-xCu3O7-d, the sintering samples and zone melting samples, were heat-treated under pure Ar at 950 °C. The substitution of Nd ion for Ba ion in the Nd1+xBa2-xCu3O7-d before and after the heat treatment was investigated by XRD. In order to confirm the effects of the heat treatment, the Tc and Jc of samples with/without the heat treatment under Ar were comparatively studied. The Nd1+xBa2-xCu3O7-d samples were oxygenated under pure oxygen at 300 °C. From the XRD pattern it was found that the sample with x<0.4 was transferred from tetragonal phase to orthorhombic phase after the oxygenation, while the sample with x>0.4 did not show the phase transition even after a long time oxygenation. Therefore, the low oxygen partial pressure (Ar + 1 % O2) was used for the ambient atmosphere of the zone-melting samples, which could reduce the melting temperature and depress the substitution of Nd for Ba. After the improvement in the zone-melting process, the Jc value was increased to 2 ´ 104 A/cm2 (0 T, 78 K). The particle orientation and the structure of zone-melted NdBaCuO were studied by the XRD and SEM analysis.