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Polar signature

RO is known as the shape descriptor (polar signature) [3]. Provided the 0increments are small enough a precise description of the boundary is obtained. If the image has a perimeter that is encountered more than once by R the descriptor can no longer regenerate the shape. For such a particle it is necessary to use equal length steps around the perimeter to define particle shape... [Pg.63]

Fig. 10. Polar signature for the growth of Pb02 from acid-acetate solution at 2 mA cm 2 (points). The smooth curve is calculated for a film of optical constants 2.05 - 0.068i growing at a rate of 3.5nms 1. The final film thickness is about 1600nm. Fig. 10. Polar signature for the growth of Pb02 from acid-acetate solution at 2 mA cm 2 (points). The smooth curve is calculated for a film of optical constants 2.05 - 0.068i growing at a rate of 3.5nms 1. The final film thickness is about 1600nm.
The polarization signatures of some of the largest MBAs (e.g., 1 Ceres and 2 Pallas) reveal surfaces that are smoother than that of the Moon at decimeter scales but much rougher at some much larger scale. For example, for... [Pg.232]

Electrochemical noise A variety of related techniques are now available to monitor localized corrosion. No external polarization of the corroding metal is required, but the electrical noise on the corrosion potential of the metal is monitored and analyzed. Signatures characteristic of pit initiation, crevice corrosion and some forms of stress corrosion cracking is obtained. [Pg.911]

A permanent EDM of a stable atomic or molecular state can arise only when both P and T invariance are broken (see Fig.l). It is often said that polar molecules possess permanent EDMs and exhibit a linear Stark effect. However, the Stark effect exhibited by the polar molecule is not really linear for sufficiently small E at zero temperature, and moreover, it violates neither P nor T symmetry [10]. We emphasize that a permanent EDM that exhibits a linear Stark effect even for an infinitesimally weak is a genuine signature of P and T violation or CP violation... [Pg.245]

It is weliknown that all static polarizations of a beam of radiation, as well as all static rotations of the axis of that beam, can be represented on a Poincare sphere [25] (Fig. la). A vector can be centered in the middle of the sphere and pointed to the underside of the surface of the sphere at a location on the surface that represents the instantaneous polarization and rotation angle of a beam. Causing that vector to trace a trajectory over time on the surface of the sphere represents a polarization modulated (and rotation modulated) beam (Fig. lb). If, then, the beam is sampled by a device at a rate that is less than the rate of modulation, the sampled output from the device will be a condensation of two components of the wave, which are continuously changing with respect to each other, into one snapshot of the wave, at one location on the surface of the sphere and one instantaneous polarization and axis rotation. Thus, from the viewpoint of a device sampling at a rate less than the modulation rate, a two-to-one mapping (over time) has occurred, which is the signature of an SU(2) field. [Pg.712]

A new method, shape signatures, in the area of computer-aided molecular design has been studied <2003JME5674>. The method has been demonstrated to work well in selecting molecules on the basis of shape and polarity and has been applied to a receptor-based strategy. Dibenzo[ /]thiepine appears in the hit list for 57/-benz[ /]azepin. [Pg.138]

When explaining the unusual rl behavior, again the appearance of fluctuating polar precursor clusters at temperatures T > Tc has to be considered as the primary signature of the polar rfim [2,3,6], Acting as precursors of the spontaneous polarization, which occurs below... [Pg.291]

The description of the chemisorption in terms of cycloaddition reactions is useful if it leads to reliable predictions of the reaction products for most reactions, a variety of products are possible, yet only one will result from a particular cycloaddition mechanism. Central to the applicability of such schemes is the notion that the silicon dimers contain a weak 7r bond responsible for the enforced concerted motion of the two electrons involved. However, in reality there is little evidence to support the presence of even a weak 7r bond within the dimers. While DFT calculations that enforce spin pairing depict the bond as a singlet biradical [32], spin-polarized calculations predict a triplet ground state for the unbuckled dimer [33] with no 7T character whatsoever. The decoupling of the two silicon electrons means that their motion is not likely to be concerted so that a [2+2] cycloaddition reaction becomes better represented as an independent [1 + 2+1] process, a notation that recognizes the independence of the silicon free radicals. This mechanism is also illustrated in Fig. 3. In practice such a reaction is unlikely to proceed in a concerted fashion, and a key signature for it would be the... [Pg.340]


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