The Meissner result shown by levitating a magnet above a cuprate superconductor, and that is cooled by liquid nitrogen Under some problems, such as incredibly small temperatures, some ceramics show high-temperature superconductivity (in superconductivity, "high temperature" indicates earlier mentioned thirty K). The reason for this is not understood, but There https://silica-magnetic-beads48035.targetblogs.com/39558689/what-does-aluminum-nitride-pcb-mean