Related to superconductivity

David Hudson quietly patented his process in England, Australia and other countries around the world. He was unable to do so in the USA. The patent application fell foul of standard US Department of Defense objections relating to superconductivity, a technology of national importance. 

Col76] Colungs, E.W. and Ho, J.C., Solute-Induced Lattice Stability as it Relates to Superconductivity in Titanium-Molybdenum Alloys, Solid State Com-mun., Yol 18,1976, p. 1493-1495... 

Nowadays there are many attempts to implement the J-T effect into the problem of superconductivity. But first something specific related to superconductivity has to be implemented into the J-T effect, viz. the Frdhlich transformation. Frdhlich did propose his transformation [10] almost 20 years after the first formulation of the J-T effect [33]. Unfortunately, this transformation is mostly known in solid-state physics (and moreover used exclusively in the superconductivity problem) and after more than a half of century it has not been integrated in the domain of quantum chemistry. It is very important for several reasons first in the explanation of the hypervibronic coupling mechanism in the J-T effect. It further takes into account not only the dependence of electronic states on the nuclear coordinates, as it is usual in the adiabatic case, but also on the nuclear momenta, which is inherent in the non-adiabatic one. This type of transformation leads to new fermion quasiparticles that... 

In this subsection are described the experiments which have been carried out so far in order to elucidatee the mechanism of superconductivity. The physical parameters related to superconductivity are summarized for 1 3 60 and Rb3C6o in Table 6.4. 

Hamiltonians equivalent to (1) have been used by many authors for the consideration of a wide variety of problems which relate to the interaction of electrons or excitons with the locaJ environment in solids [22-25]. The model with a Hamiltonian containing the terms describing the interaction between excitons or electrons also allows for the use of NDCPA. For example, the Hamiltonian (1) in which the electron-electron interaction terms axe taken into account becomes equivalent to the Hamiltonians (for instance, of Holstein type) of some theories of superconductivity [26-28]. 

The generally accepted theory of electric superconductivity of metals is based upon an assumed interaction between the conduction electrons and phonons in the crystal.1-3 The resonating-valence-bond theory, which is a theoiy of the electronic structure of metals developed about 20 years ago,4-6 provides the basis for a detailed description of the electron-phonon interaction, in relation to the atomic numbers of elements and the composition of alloys, and leads, as described below, to the conclusion that there are two classes of superconductors, crest superconductors and trough superconductors. 

Nickel atoms in BajNi B form distorted, puckered 3.6.3.6-kagome nets stacked in six layers perpendicular to the c axis. The densely packed framework of trigonal-Ni prisms again result in boron-pair formation, although Ba atoms are too large to be sandwiched between two Ni layers, and only four Ba can be accommodated within six Ni layers. Superconductivity is found for ( a, Sr, Ba)2pt9Bg borides with a structure related to Ba2Ni9Bfi and e o,B2 however, with respect to crystal chemistry and boron coordination, only the subcell is derived so far. 

Stereoisomers Diastereoisomers related to each other by the inversion of any number of chiral centres. Superconduction Conduction of electric current with zero resistance. This phenomenon occurs at liquid helium temperature and has made possible the construction of the very high powered magnets that we see in today s spectrometers. 

Among various superconductors, compounds with the A15 (Cr3Si) crystal structure have the highest critical temperatures. This crystal structure has a simple relationship with the Ll2 structure (Ito and Fujiwara, 1994) as illustrated in Figure 8.9. When the unit cells are aggregated, the face-centered pairs of atoms form uniform chains of transition metal atoms along three orthogonal directions. This feature may be related to the relatively stable superconductivity in compounds with this structure. 

Figure 7. At / = 0.75, pressure as a function of/./ = / e / > and for the normal and color superconducting quark phases. The dark solid lines represent two locally neutral phases (i) the neutral normal quark phase on the left, and (ii) the neutral gapless 2SC phase on the right. The appearance of the swallowtail structure is related to the first order type of the phase transition in quark matter.

It is interesting to notice that the three pressure surfaces in Figure 7 form a characteristic swallowtail structure. As one could see, the appearance of this structure is directly related to the fact that the phase transition between color superconducting and normal quark matter, which is driven by changing parameter //,. is of first order. In fact, one should expect the appearance of a similar swallowtail structure also in a self-consistent description of the hadron-quark phase transition. Such a description, however, is not available yet. 

Abstract Two aspects of quark matter at high density are addressed one is color superconductivity and the other is ferromagnetism. We are mainly concerned with the latter and its relation to color superconductivity, which we call color magnetic superconductivity. The relation of ferromagnetism and chiral symmetry restoration is also discussed. 

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