Magnesium diboride

Magnesium cyanide, 8 197 Magnesium diboride. See MgB2 entries Magnesium dichromate, molecular... 

The two band superconductivity has been proposed for metallic elements and alloys [10-42], for doped cuprate perovskites [43-114], for magnesium diboride [115-184] and for few other materials as Nb doped SrTiCE [185], Sr2Ru04 [186-188] YNi2B2C, LuNi2B2C [189] andNbSe2 [190], We provide a nearly complete reference list on this subject since it is not available elsewhere. 

The Lifshitz parameter z as a function of x in the case of the A1 and Sc substitutions for Mg in the Mgi xAlxB2, and Mgi xScxB2 systems and for the C for B substitution in the MgB2.xCx system has been calculated by R. De Coss et al. by band structure calculations described elsewhere [204] therefore it has been possible to convert the variation of the critical temperature as a function of the number density of substituted ions x to the variation of Tc versus the universal reduced Lifshitz parameter z for all doped magnesium diborides. 

Figure 1 2 12. The critical temperature in aluminum, scandium and carbon doped magnesium diborides as a function of the Lifshitz parameter z = (Er-Ep )/(EA-Er)...

The discussions in the informal and friendly atmosphere of Erice was on new experimental data showing that high Tc in doped cuprate perovskites is related with the nanoscale phase separation and the two component scenario, the two-band superconductivity in magnesium diboride and the lower symmetry in the superconducting elements at high pressure. 

Schneider, M., Thermische Tieftemperatureigenschaften von Magnesium-Diborid und Seltenerd-Nickel-Borkarbiden, Thesis, TU Dresden 2005. 

If a breakthrough occurs with the permanent magnets, ceramic conductor or magnesium diboride technology, some, of the initial investment in the niobium metallic magnet facility may be wasted. This type of risks must be accepted. If we wait until there is no technological uncertainty, the reactors will never be built. 

Canfield, Paul C., and George W. Crabtree. Magnesium Diboride Better Late than Never. Physics Today 56 (2003) 34. Article describes the history and discovery as well as superconducting properties of magnesium diboride. 

LiAIF4[g] LITHIUM TETRAFLUOROALUMINATE (GAS) 946 MgB2 MAGNESIUM DIBORIDE 995... 

Intentionally, the neutron-radiation treatment is nsed to obtain structural disorder in magnesium diboride, MgB2, which is an interesting high-temperature superconducting material. The temperature... 

A relatively high superconducting transition temperature Tc = 39 K of magnesium diboride MgB2 was discovered in 2001. Investigation of this composition is an excellent example of combination of theory and experiment to understand the mechanism of superconductivity. The electron structures of atoms are... 

Figure 9.5 Crystal structure of magnesium diboride, electronic states and a vibrational mode of boron atoms, (a) Crystal structure of MgB2, hexagonal honeycomb layers of boron atoms alternate with layers of magnesium atoms, centered on the hexagons.

In another encouraging development, in 2001 scientists in Japan discovered that magnesium diboride (MgB2) becomes superconducting at about 40 K. 

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