Decomposition of solid solutions in the Nd-Ba-Cu-O system and its   influence on changing transport characteristics
  Thermochemical characteristics of Nd1+xBa2-xCu3Oy solid solutions were studied by solution calorimetry. Dependences of formation enthalpies from Nd content were constructed. It was established that decomposition of solid solution on the basis of Nd123 phase took place both in inert and in oxygen atmosphere. As a result of decomposition the different mixtures such as solid solutions with increasing and decreasing Nd content and BaCuO2 were formed. Obtained thermochemical data were compared with results of measurements of transport characteristics. It was established that treatment of samples at 550-600 C led to increasing critical current and decreasing Tc. 
N.I. Matskevich, O.I. Anyfrieva, T.D. Karpova (Nikolaev Institute of   Inorganic Chemistry, Siberian Branch of the Russian A...