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Superconductors may be considered perfect diamagnets, and completely expel magnetic fields due to the Meissner effect when the superconductivity initially forms; thus superconducting levitation can be considered a particular instance of diamagnetic levitation. In a type-II superconductor, the levitation of the magnet is further stabilized due ...
The experiment demonstrated for the first time that superconductors were more than just perfect conductors and provided a uniquely defining property of the superconductor state. The ability for the expulsion effect is determined by the nature of equilibrium formed by the neutralization within the unit cell of a superconductor.
A superconductor can be Type I, meaning it has a single critical field, above which all superconductivity is lost and below which the magnetic field is completely expelled from the superconductor; or Type II, meaning it has two critical fields, between which it allows partial penetration of the magnetic field through isolated points. [32]
Superdiamagnetism established that the superconductivity of a material was a stage of phase transition. Superconducting magnetic levitation is due to superdiamagnetism, which repels a permanent magnet which approaches the superconductor, and flux pinning, which prevents the magnet floating away. Superdiamagnetism is a feature of superconductivity.
In aerodynamic levitation, the levitation is achieved by floating the object on a stream of gas, either produced by the object or acting on the object. For example, a ping pong ball can be levitated with the stream of air from a vacuum cleaner set on "blow" - exploiting the Coandă effect which keeps it stable in the airstream.
The wire or tape itself may be made of tiny filaments (about 20 micrometres thick) of superconductor in a copper matrix. The copper is needed to add mechanical stability, and to provide a low resistance path for the large currents in case the temperature rises above T c or the current rises above I c and superconductivity is
There are two London equations when expressed in terms of measurable fields: =, =. Here is the (superconducting) current density, E and B are respectively the electric and magnetic fields within the superconductor, is the charge of an electron or proton, is electron mass, and is a phenomenological constant loosely associated with a number density of superconducting carriers.
Metalloprotein is a generic term for a protein that contains a metal ion cofactor. [1] [2] A large proportion of all proteins are part of this category. For instance, at least 1000 human proteins (out of ~20,000) contain zinc-binding protein domains [3] although there may be up to 3000 human zinc metalloproteins. [4]