A copper cannon belong to Western Hsia Dynasty(A.D.1032~1227)had been unearthed incity Wuwei in Province Gansu.This cannon is confirmed as an oldest metallic tub
Following the discovery ofthe high T<sub>c</sub> Y—Ba—Cu—O systemsuperconaductor,<sup>(1,2)</sup>a new highT<sub>c</sub> superconductor without rare—earthshav
A copper-electrolysis engineering——Zhujiang Copper Manufacturing Plant——will haveput into operation in the near future.This plant is the biggest metallurgic