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Figure 2 Superconducting tables in the periodic table. Superconductors at ambient conditions are noted in gray colour brown is used for superconducting elements at high pressure. No superconductivity has been reported for the rest of the elements... Figure 2 Superconducting tables in the periodic table. Superconductors at ambient conditions are noted in gray colour brown is used for superconducting elements at high pressure. No superconductivity has been reported for the rest of the elements...
Sihcon is a Group 14 (IV) element of the Periodic Table. This column iacludes C, Si, Ge, Sn, and Pb and displays a remarkable transition from iasulatiag to metallic behavior with increasing atomic weight. Carbon, ia the form of diamond, is a transparent iasulator, whereas tin and lead are metals ia fact, they are superconductors. SiUcon and germanium are semiconductors, ie, they look metaUic, so that a poHshed siUcon wafer is a reasonable gray-toned mirror, but they conduct poorly. Traditionally, semiconductors have been defined as materials whose resistance rises with decreasiag temperature, unlike metals whose resistance falls. [Pg.344]

There are presently four famihes of high-temperature superconductors under investigation for practical magnet appheations. Table 11-25 shows that all HTS are copper oxide ceramics even though the oxygen content may vary. However, this variation generally has little effect on the phvsical properties of importance to superconductivity. [Pg.1127]

In the next breath you take, almost all the atoms you inhale will be of elements in the final four groups of the periodic table. Except for the gases containing carbon and hydrogen, air is made up almost entirely of elements from this part of the p block, some as elements and some as compounds. The p-block elements are present in most of the compounds necessary for life and are used to create fascinating and useful modern materials, such as superconductors, plasma screens, and high-performance nanodevices. [Pg.743]

Table 1. Calculation of Tcfor superconductors of the second long period. Table 1. Calculation of Tcfor superconductors of the second long period.
The acetylacetonates are stable in air and readily soluble in organic solvents. From this standpoint, they have the advantage over the alkyls and other alkoxides, which, with the exception of the iron alkoxides, are not as easily soluble. They can be readily synthesized in the laboratory. Many are used extensively as catalysts and are readily available. They are also used in CVD in the deposition of metals such as iridium, scandium and rhenium and of compounds, such as the yttrium-barium-copper oxide complexes, used as superconductors. 1 1 PI Commercially available acetyl-acetonates are shown in Table 4.2. [Pg.91]

Niobium nitride (also known as columbium nitride) has three phases Nb2N, Nb4N3, and NbN. The mononitride, NbN, is the most common phase and the only one reviewed here. NbN is an excellent superconductor. It is produced by CVD mostly on an experimental basis. Its characteristics and properties are summarized in Table 10.5. [Pg.278]

Figure 1 The elements of the Periodic Table which behave as superconductors at atmospheric pressure and at temperatures lower than 10 K... Figure 1 The elements of the Periodic Table which behave as superconductors at atmospheric pressure and at temperatures lower than 10 K...
Table 1.8. Material, P and of selected molecular organic superconductors classified according to the point group of the donor... Table 1.8. Material, P and of selected molecular organic superconductors classified according to the point group of the donor...
The series of 2D superconductors based on the BEDT-TTF molecule is extremely rich because of the large number of polymorphs and because, to date, they exhibit the highest Tc values with Tc 12.8 K for x-(BEDT-TTF)2Cu[N(CN)2]Cl (see Table 1.8). Figure 1.20 shows different arrangements of the BEDT-TTF layers for the a,, y, 8, k and 9 crystallographic phases. The a-phase exhihits... [Pg.39]

Table 6 Four typical K-type superconductors with Tc above 10 K (29 - 32) and a Mott insulator (34)... Table 6 Four typical K-type superconductors with Tc above 10 K (29 - 32) and a Mott insulator (34)...
At this point, it may be informative to present a chronological listing of the different discoveries in oxide superconductors reported prior to 1975. In this listing, Table 5, we present the year that the oxide compound was first reported, then the year in which superconductivity was first observed in the system and the group credited for the discovery. Of particular interest is the compound Ba(Pb1 xBix)Os discovered by Sleight at du Pont in 1975. This oxide material adopts the perovskite-type structure and contains no transition metals. [Pg.21]

TABLE 8 Table of "Tungsten Bronze" Superconductors with Tc data. [Pg.41]

An outline of possible ion substitutions in the new 1-2-3 superconductor (90 K material) based on ionic radii is presented in Table 12. [Pg.90]

Various substitution studies (171-173) were conducted in the early stages of research on these new oxide superconductors. One most dramatic result was the facile substitution of other (magnetic) lanthanide ions for yttrium in the VUI-coordinated site of the structure. The incorporation of these magnetic ions had no effect on the superconductivity nor the Tc of the material— quite astounding, since the presence of magnetic ions in superconductors was previously believed to destroy the phenomenon entirely Table 13 presents several examples of such substituted compounds. [Pg.90]

The compound NCu02 (N = Ca0 86Sr014) is an insulator, but its structure, which is a simple defect perovskite made of layers (CuOa) sandwiched between layers (N), can be considered as the parent structure of a large family of superconductors. The sequence. ..(Cu0 )OiC(N)e o(Cu02)OjC. .. is in fact one of the building blocks of many compounds considered in this review. The refined parameters for NCu02 are given in Table 3. [Pg.201]

Crystal Growth and Solid State Synthesis of Oxide Superconductors 235 Table II. Summary of standard fluxes. [Pg.235]

The idea behind this solid solution is simple enough. Starting from BaBiOs, the substitution of Pb for Bi removes electrons from the system, as Pb is one element to the left of Bi in the periodic table. Obviously, electrons can also be removed from the system by substitution of K+1 for Ba2+. If we suppose that the key to the occurrence of superconductivity in BaPb 75-Bi 25Os is related to the special charge fluctuations in Bi, then, in analogy to the copper oxides, a material with solely the active component on the electronically active sites should be a better superconductor. For the Ba K BiOg solid solution, Bi is formally... [Pg.410]

Table 1 A Survey of Microprobe Analysis Results for the 2212 Bi-Sr-Ca-Cu-O Superconductor... Table 1 A Survey of Microprobe Analysis Results for the 2212 Bi-Sr-Ca-Cu-O Superconductor...

See other pages where Tables superconductors is mentioned: [Pg.308]    [Pg.300]    [Pg.419]    [Pg.61]    [Pg.261]    [Pg.827]    [Pg.144]    [Pg.82]    [Pg.370]    [Pg.371]    [Pg.2]    [Pg.370]    [Pg.109]    [Pg.61]    [Pg.36]    [Pg.70]    [Pg.87]    [Pg.92]    [Pg.103]    [Pg.19]    [Pg.28]    [Pg.40]    [Pg.85]    [Pg.217]    [Pg.234]    [Pg.407]    [Pg.600]   
See also in sourсe #XX -- [ Pg.41 ]




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