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Signs electricity

The sign electric field dependence in (11) may be defined by anisotropy parameter... [Pg.354]

Helium is used along with oxygen by divers. Neon is used in neon sign electrical discharge tubes. Argon, krypton and xenon, are used in incandescent lamps. Radon a radioactive noble gas is used in the treatment of malignant growths. [Pg.139]

The above peculiarities of relaxor ferroelectrics appear due to random electric field, induced by two factors. First one is substitutional disorder in cations positions, which leads to local shift of ions from their equilibrium positions. Second one is the presence of vacancies and other unavoidable defects. The shifted ions can be considered as random site electric dipoles, which are the sources of constant and alternating sign electric field (see Sect. 1.4.1). The former tends to order the system... [Pg.28]

Flexible permanent magnets are used for signs, electric motors, toys, sealing strips, etc. They are fabricated from compounds with up to 90 percent by weight of magnetizable filler. Binders can be chlorinated and chlorosulfonated polyethylene, various vinyl compounds, nitrile rubber, and ethylene/ethyl aaylate copolymers. Magnetization is typically accomplished, via a magnetic field, after extrusion. [Pg.335]

Bombardment of a liquid surface by a beam of fast atoms (or fast ions) causes continuous desorption of ions that are characteristic of the liquid. Where the liquid is a solution of a sample substance dissolved in a solvent of low volatility (often referred to as a matrix), both positive and negative ions characteristic of the solvent and the sample itself leave the surface. The choice of whether to examine the positive or the negative ions is effected simply by the sign of an electrical potential applied to an extraction plate held above the surface being bombarded. Usually, few fragment ions are observed, and a sample of mass M in a solvent of mass S will give mostly [M + H] (or [M - H] ) and [S -I- H]+ (or [S - H] ) ions. Therefore, the technique is particularly good for measurement of relative molecular mass. [Pg.81]

Electrostrictive materials are materials that exhibit a quadratic relationship between mechanical stress and the square of the electric polari2ation (14,15). Electrostriction can occur in any material. Whenever an electric field is appHed, the induced charges attract each other, thus, causing a compressive force. This attraction is independent of the sign of the electric field and can be approximated by... [Pg.249]

Electrostatic Interactions. This is the mechanism that operates when adsorption sites and reagents carry opposite electrical charge signs. [Pg.48]

Nonlinear Optical Devices. A transparent, optically active, sol—gel-derived organic—inorganic glass has been synthesized (68). This hybrid consists of a 2,4-dinitroaminophenylpropyl-triethoxysilane covalently bound to a siUcon alkoxide-derived siUca network. This hybrid exhibits a strong electric field-induced second harmonic signal and showed no signs of crystallization. [Pg.331]

The absence of an electron from a covalent bond leaves a hole and the neighboring valence electron can vacate its covalent bond to fill the hole, thereby creating a hole in a new location. The new hole can, in turn, be filled by a valence electron from another covalent bond, and so on. Hence, a mechanism is estabUshed for electrical conduction that involves the motion of valence electrons but not free electrons. Although a hole is a conceptual artifact, it can be described as a concrete physical entity to keep track of the motion of the valence electrons. Because holes and electrons move in opposite directions under the influence of an electric field, a hole has the same magnitude of charge as an electron but is opposite in sign. [Pg.467]

Dipole. Every amino acid molecule has two equal electric charges of opposite sign caused by the amino and carboxyl groups on the a-carbon... [Pg.274]

When the Clean Air Act of 1990 was signed into law, electric utiUties were requited to estabUsh plans and initiate projects to comply with that Act s Tide IV. Each utihty had to evaluate how the various commercial and emerging clean coal systems fit into the utiUty s technical and business environment resulting in strategies to utilize fuel switching and wet throwaway FGD processes almost exclusively (38,85,86). [Pg.264]

The principle of the measurement is described with the help of Fig. 2-7 [50]. Potential measurement is not appropriate in pipelines due to defective connections or too distant connections and low accuracy. Measurements of potential difference are more effective. Figure 3-24 contains information on the details in the neighborhood of a local anode the positions of the cathodes and reference electrodes (Fig. 3-24a), a schematic representation of the potential variation (Fig. 3-24b), and the derived values (Fig. 3-24c). Figure 2-8 should be referred to in case of possible difficulties in interpreting the potential distribution and sign. The electrical potentials of the pipeline and the reference electrodes are designated by... [Pg.124]


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See also in sourсe #XX -- [ Pg.237 ]




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Relative sign of electric field strength and polarization

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