High-77 superconductors impurity effects

Some chemical aspects such as the effects of comosition and impurities on the manifestation of superconductivity in high-Tc oxides have been described. They are shown to be quite significant in determining superconducting behavior and probably many other physical properties of these materials as well. As the developments of oxide superconductors with higher Tc and better quality continue, it should be essential to take these aspects fully into account. 

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