Since Michel et al.discoveredsuperconductivity of the BiSrCuO system at20K,the work of synthesizing highT_c superconductors without rare-earth byadding some el
The TiN coatings on the surfaces of various cemented carbides were performed by use of reactive magnetron sputtering.Thehighest microhardness which was obtaine
Stepping into ancient Xi’an is like being transported back thirteen dynasties when the Zhou,Qin,Han and Tang dynasties ruled.The omnipresent past still lingers