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Subject polarization

The skin shell forms a high-density phase that is more elastic, stiffer, chemically and thermally less stable with entrapped electrons, and subjective polarization. Bond relaxation happens only in the skin in a radial way. The extent and depth of bond relaxation increase with surface curvature. [Pg.223]

Defects and edges are associated with local bond strain, entrapment, and the subjective polarization. [Pg.239]

All undercoordinated systems demonstrate the electronic feature of global quantum entrapment and the subjective polarization. Undercoordinated atoms of Au, Ag, Rh, and W show both entrapment and polarization, while the undercoordinated Co and Pt atoms show only entrapment. One neighbor short makes the C atom at the defect site and the ZGNR edge to be completely different from that in the flat graphite surface and in the GNR interior and AGNR edge. [Pg.248]

Undercoordination induces global enttapment by subjective polarization depending on the electronic configuration of the outermost electron shell of the substance. [Pg.421]

If maltenes are subjected to liquid chromatography (see 2.1.2.4) the components eluted by the more polar solvents are called resins. Their composition, once again, depends on the procedure used. [Pg.15]

Liquid chromatography is preceded by a precipitation of the asphaltenes, then the maltenes are subjected to chromatography. Although the separation between saturated hydrocarbons and aromatics presents very few problems, this is not the case with the separation between aromatics and resins. In fact, resins themselves are very aromatic and are distinguished more by their high heteroatom content (this justifies the terms, polar compounds or N, S, 0 compounds , also used to designate resins). [Pg.83]

The polarization P is given in tenns of E by the constitutive relation of the material. For the present discussion, we assume that the polarization P r) depends only on the field E evaluated at the same position r. This is the so-called dipole approximation. In later discussions, however, we will consider, in some specific cases, the contribution of a polarization that has a non-local spatial dependence on the optical field. Once we have augmented the system of equation B 1.5.16. equation B 1.5.17. equation B 1.5.18. equation B 1.5.19 and equation B 1.5.20 with the constitutive relation for the dependence of Pon E, we may solve for the radiation fields. This relation is generally characterized tlirough the use of linear and nonlinear susceptibility tensors, the subject to which we now turn. [Pg.1271]

An alternative approach to obtaining microwave spectroscopy is Fourier transfonn microwave (FTMW) spectroscopy in a molecular beam [10], This may be considered as the microwave analogue of Fourier transfonn NMR spectroscopy. The molecular beam passes into a Fabry-Perot cavity, where it is subjected to a short microwave pulse (of a few milliseconds duration). This creates a macroscopic polarization of the molecules. After the microwave pulse, the time-domain signal due to coherent emission by the polarized molecules is detected and Fourier transfonned to obtain the microwave spectmm. [Pg.2441]

Calculations within tire framework of a reaction coordinate degrees of freedom coupled to a batli of oscillators (solvent) suggest tliat coherent oscillations in the electronic-state populations of an electron-transfer reaction in a polar solvent can be induced by subjecting tire system to a sequence of monocliromatic laser pulses on tire picosecond time scale. The ability to tailor electron transfer by such light fields is an ongoing area of interest [511 (figure C3.2.14). [Pg.2987]

Water-soluble globular proteins usually have an interior composed almost entirely of non polar, hydrophobic amino acids such as phenylalanine, tryptophan, valine and leucine witl polar and charged amino acids such as lysine and arginine located on the surface of thi molecule. This packing of hydrophobic residues is a consequence of the hydrophobic effeci which is the most important factor that contributes to protein stability. The molecula basis for the hydrophobic effect continues to be the subject of some debate but is general considered to be entropic in origin. Moreover, it is the entropy change of the solvent that i... [Pg.531]

In reverse-phase chromatography, which is the more commonly encountered form of HPLC, the stationary phase is nonpolar and the mobile phase is polar. The most common nonpolar stationary phases use an organochlorosilane for which the R group is an -octyl (Cg) or -octyldecyl (Cig) hydrocarbon chain. Most reverse-phase separations are carried out using a buffered aqueous solution as a polar mobile phase. Because the silica substrate is subject to hydrolysis in basic solutions, the pH of the mobile phase must be less than 7.5. [Pg.580]

The sohd line in Figure 3 represents the potential vs the measured (or the appHed) current density. Measured or appHed current is the current actually measured in an external circuit ie, the amount of external current that must be appHed to the electrode in order to move the potential to each desired point. The corrosion potential and corrosion current density can also be deterrnined from the potential vs measured current behavior, which is referred to as polarization curve rather than an Evans diagram, by extrapolation of either or both the anodic or cathodic portion of the curve. This latter procedure does not require specific knowledge of the equiHbrium potentials, exchange current densities, and Tafel slope values of the specific reactions involved. Thus Evans diagrams, constmcted from information contained in the Hterature, and polarization curves, generated by experimentation, can be used to predict and analyze uniform and other forms of corrosion. Further treatment of these subjects can be found elsewhere (1—3,6,18). [Pg.277]

Structure. The straiued configuration of ethylene oxide has been a subject for bonding and molecular orbital studies. Valence bond and early molecular orbital studies have been reviewed (28). Intermediate neglect of differential overlap (INDO) and localized molecular orbital (LMO) calculations have also been performed (29—31). The LMO bond density maps show that the bond density is strongly polarized toward the oxygen atom (30). Maximum bond density hes outside of the CCO triangle, as suggested by the bent bonds of valence—bond theory (32). The H-nmr spectmm of ethylene oxide is consistent with these calculations (33). [Pg.452]

This is one approach to the explanation of retention by polar interactions, but the subject, at this time, remains controversial. Doubtless, complexation can take place, and probably does so in cases like olefin retention on silver nitrate doped stationary phases in GC. However, if dispersive interactions (electrical interactions between randomly generated dipoles) can cause solute retention without the need to invoke the... [Pg.76]

One of the other benefits of incorporating polar monomers in the PSA is the enhancement in cohesive strength. This can be observed in the form of higher shear holding in a static shear test and/or better creep resistance of the adhesive when subject to a constant load. [Pg.490]

The measured relationships between piezoelectric polarization and strain for x-cut quartz and z-cut lithium niobate are found to be well fit by a quadratic relation as shown in Fig. 4.4. In both materials a significant nonlinear piezoelectric effect is indicated. The effect in lithium niobate is particularly notable because the measurements are limited to much smaller strains than those to which quartz can be subjected. The quadratic polynomial fits are used to determine the second- and third-order piezoelectric constants and are summarized in Table 4.1. Elastic constants determined in these investigations were shown in Chap. 2. [Pg.79]

Certainly the most prominent feature of the breakdown process is its dependence on the polarity of the electric field relative to the shock-velocity vector. This effect is manifest in current pulse anomalies from minus-x orientation samples or positively oriented samples subjected to short-pulse loading (see Fig. 4.8). The individual effects of stress and electric field may be delineated with short-pulse loadings in which fields can be varied by utilizing stress pulses of various durations [72G03]. [Pg.88]


See other pages where Subject polarization is mentioned: [Pg.244]    [Pg.281]    [Pg.1189]    [Pg.1214]    [Pg.2466]    [Pg.2971]    [Pg.102]    [Pg.210]    [Pg.351]    [Pg.291]    [Pg.334]    [Pg.299]    [Pg.221]    [Pg.496]    [Pg.244]    [Pg.297]    [Pg.296]    [Pg.521]    [Pg.339]    [Pg.171]    [Pg.9]    [Pg.2431]    [Pg.80]    [Pg.598]    [Pg.170]    [Pg.341]    [Pg.417]    [Pg.21]    [Pg.445]    [Pg.465]    [Pg.100]    [Pg.294]    [Pg.605]    [Pg.67]   
See also in sourсe #XX -- [ Pg.142 , Pg.145 , Pg.147 , Pg.148 , Pg.160 ]




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