Surface sheet

Even when plastics are not a preferred material for the stmctural element of paneling, they are often iacorporated as a surface coatiag or sheet to enhance aesthetics. Some lay-ia ceiling panels for commercial and iastitutional appHcations consist of gypsum board covered with a poly(vinyl chloride) surface sheet to add a textured appearance. Many more are based on gypsum board or mineral wall with a fiber glass or PVC surface. 

The non-local effects can result in an anisotropy of Hc2 microscopically due to the anisotropy of the pairing state (Shiraishi et al., 1999) or directly to the anisotropy in the shape of the Fermi surface (Metlushko et al., 1997). The anisotropy of the Fermi surface sheets (see Section 3.2) has been assumed to cause the mentioned basal anisotropy of Hc2 because the borocarbide superconductors are usually clean-limit type-II superconductors. In the clean limit for an anisotropic Fermi surface the non-local corrections to Hc2 are given by... 

The field-effect method measures the surface sheet conductance as a function of applied voltage at the semiconductor-insulator interface in MOS device structures. This surface conductance depends on the degree of carrier accumulation or depletion at the interface, which in turn depends on the band-bending function for a given applied gate voltage. This band bending is... 

By the same procedure Campana et al. (1973) have shown the existence of a non-saturated surface sheet at a temperature as far below the ordering temperature of the bulk as 16.75 K. Surface spin-exchange scattering due to 4f-electron excitations explains this result. Bush et al. (1969) observed spin polarization, which can be due to impurities, in semiconducting ferromagnetic EuS films. They proposed this occurs because of an exchange interaction of the impurities with the 4f levels. 

Fig. 16. CeRu2Si2 Fermi surface sheets for quasiparticles with f-character. The labels xj/ and a, 8, refer to the branches observed in dHvA experiments (Lonzarich, 1988 Albessard et al., 1993). Left Hole surface centered around the Z-point of the Brillouin zone with effective mass m 100m which dominates the specific heat y-value. For localized f-electrons at elevated temperatures, the hole surface expands extending to the boundaries of the Brillouin zone while the multiply connected electron-like surface shrinks. The expansion of xj/ is confirmed by photoemission experiments. Right Multiply-connected electron-like sheet.

As discussed in sect. 2 the observation of the dHvA effect far in the vortex phase B < Bc2) is a sure signature of nodal superconductivity. Although oscillations of the three Fermi surface sheets in URu2Si2 have been seen below Bc2 (Ohkuni et al., 1999) the amplitude falls of quite rapidly with B, especially for field along c. Therefore, these experiments are not able to confirm the existence of nodes in A (k). 

ATH came into wide use as a flame retardant in the 1960s, primarily as a result of demands of consumer-driven safety legislation for carpet backing and fiberglass-reinforced polyester products. For these applications, ATH imparts flame retardance and smoke suppression. End-use markets for ATH include transportation, construction, cast polymers, electrical/electronic, wire and cable, leisure and appliances. Specific polymer applications range from thermosets such as solid surface, sheet molding compounds (SMCs) and bulk molding compounds (BMCs) to wire and... 

Alpha paper n. Paper made from purified wood cellulose, often beautifully preprinted when used as surfacing sheets of decorative laminates. 

Overlay sheet (top sheet, surfacing mat) n. A non-woven fibrous mat of glass or synthetic fiber used as the surfacing sheet in decorative laminates. Its function is to provide a smoother finish, hide the fibrous pattern of the laminate, and/or to provide... 

Fig. 21. Photoemission spectra along various cuts through the Brillouin zone, clearly revealing a Fermi sur ce crossing. The lower portion schematically illustrates the points in -space conesponding the each spectrum. A second Fermi surface sheet is indicated by the hatched line.

Besides YBa2Cu307, 2D-ACAR has been measured in compounds of the same structure but with different rare earths R=Dy, Ho and Pr (Hoffmann et al. 1993a, 1995). It has been concluded that the electronic structure of these compounds is similar to that of YBa2Cu307, as suggested by band-structure calculations. The ridge, i.e. the Fermi surface sheet originating from the Cu-O chains, is almost unchanged, as probably are the other sheets of the Fermi surface. 

CEM-3, a composite of dissimilar core materials, uses an epoxy resin impregnated, non-woven fiberglass core with epoxy resin impregnated, woven fiberglass cloth surface sheets. It is higher in cost than CEM-1, but is more suitable for plated through holes. CEM-3 has been used in early home computers, automobiles, and home entertainment products. 

Fermi surface sheets which were used to calculate the dHvA frequencies in fig. 73 are shown in fig. 74. The Fermi surfaces proposed by Zwicknagl et al. (1990) and Yamagami and Hasegawa (1993) actually look similar to each other. In calculations of the former, adjustable parameters were used to fit the theoretical dHvA frequencies to the observed ones, while no such phenomenological procedure was employed in calculations of the latter. Therefore, we discuss the origins of dHvA branches on the basis of the Fermi surfaces calculated by Yamagami and Hasegawa. 

The trivalent character of TmS is further confirmed by M edge X-ray absorption (XA) by Kaindl et al. (1983), where one observes a transition 3d °4f3d 4f which exhibits three dipole allowed lines at the My energy as demanded by theory. In addition Kaindl et al. (1982) show also that TmS has a surface sheet of divalent Tm as observed with surface sensitive photoemission. The reason for this is explained below. 

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