Earth permittivity

There were no computers in the 1920s thus, it was impossible to use Pollaczek s impedance [8]. Carson derived the same formula as Pollaczek, neglecting the earth permittivity (i.e., =... 

It should be noted that Pollaczek and Carson assumed uniform current distribution along a conductor and neglect the earth permittivity. If those are considered, the denominator of the... 

Earth resistivity, as mentioned earlier, is weather/climate dependent. The resistivity after the rains is lower than that measured during dry days. Also, it may be frequency dependent. The frequency dependence of earth permittivity may be far more significant than that of earth resistivity. Furthermore, water (H2O), which is a dominant factor for earth permittivity, is extremely temperature dependent [18]. As a result, the error due to the uncertainty of earth resistivity and permittivity might be far greater than that due to the incompleteness of the earth-return impedance derived by Carson and Pollaczek. This should be remembered as a physical reality that is important in engineering practice. 

One way to achieve such improvements is by doping of aluminum oxide with properly selected impurities. These could be introduced by implantation into aluminum and subsequent transfer into the oxide during anodization.331 Alternatively, complex anions containing impurity atoms could be introduced into the anodizing bath [see Section IV(2)]. The incorporated anions influence the dielectric permittivity, E, of the oxide.176 Hence, one can manipulate the E value by changing the electrolyte concentration and anodization regime.91 According to the published data, rare-earth-doped... 

Temperature Dependence of the Permittivity (Dielectric Constant) of Liquids The Earth Its Mass, Dimensions, and Other Related Quantities The Limits of Superheat of Pure Liquids... 

Figure 6 shows the effect of alkaline earth oxides on the maximum permittivity of polycrystalline BT2. The maximum permittivity of SrO substituted polycrystalline BT2 specimens showed the highest value of 3300 at x = 0.01. The maximum permittivity of CaO substituted polycrystalline BT2 specimens showed the highest value of 4950 at x = 0.03. The maximum permittivity of MgO substituted polycrystalline BT2 specimens showed the highest value of 3250 at x = 0.005. The Ca element was the most effective to increase the permittivity of polycrystalline BT2 which may be... 

The mutual dependences of the pressure, the compressibility, the permittivity, and the field strength complicate the electrostatic calculations. Marcus has recently calculated (Marcus 2009, 2012a) the Vieiec°° for the alkali metal and alkaline earth metal cations and the halide, perchlorate, and sulfate anions for aqueous solutions at five temperatures between 273.15 and 473.15 K (0 - 200 °C), those for 298.15 K being shown in Table 2.2. The corresponding intrinsic volumes are Vi intr = -... 

Capacitors BaTiOg, rare earth oxide High permittivity, low dielectric loss, controllable coefficients of thermal expansion, high breakdown voltages... 

Dielectric data for microwave dielectric materials, namely, the relative dielectric permittivity (e,), the product of the quality factor Q and the frequency (Q x/), the frequency of the measurement (/), and the temperature coefficient of the resonance frequency (xf) based on rare earth aluminates are listed in Table 30. Measurements carried out using low-frequency (MHz) impedance methods are... 

FIGURE 53 Relative dielectric permittivity versus rare earth ionic radius. The dashed lines are linear fits CrtriO = IHIO Pr and r(rR) = —52 64 Tr. 

In contrast to rare earth aluminates, the microwave dielectric properties (dielectric permittivities and losses) of rare earth orthogallates were studied less. The relative dielectric permittivity in LaGaOa has been reported to be 25 (Sandstrom et al., 1988), in PrGaOa, is 24 (Sasaura et al., 1990a), whereas in neodymium gallate, from 20 to 23 were given by different authors (Konaka et al., 1991 Konopka and... 

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