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Curvature center

The second energy derivatives with respect to the x, y, and z directions of centers a and b (for example, the x, y component for centers a and b is Hax,by = (3 E/dxa3yb)o) form the Hessian matrix H. The elements of H give the local curvatures of the energy surface along the 3N cartesian directions. [Pg.513]

Foi shts placed at from the center of curvature, the electrons passed by this analyzer foUow the equipotential surface described by R. With an acceptance angle 8a shown in Figure 22 and a sht width w, the energy resolution of the CFIA is given by... [Pg.284]

Data Communication Wires. Electronic cables such as data communication wires employ three basic designs coaxial, twisted pair, and fiber optics (3,4) (Eig. 1). Coaxial cables are so named because the axis of curvature of its outer conductor is concentric to its inner central wire. The metal braiding wrapped around the insulated center wire acts as the return current conductor in addition to shielding the wire from various interferences. [Pg.322]

When the isobars are curved, an additional force, a centrifugal force outward from the center of curvature, enters into the balance of forces. In the case of curvature around low pressure, a balance of forces occurs when the pressure gradient force equals the sum of the coriolis and centrifugal forces (Fig. 17-12) and the wind continues parallel to the isobars. In the... [Pg.259]

The CHA is shown in schematic cross-section in Fig. 2.5 [2.5]. Two hemispheres of radii ri (inner) and T2 (outer) are positioned concentrically. Potentials -Vi and -V2 are applied to the inner and outer hemispheres, respectively, with V2 greater than Vi. The source S and the focus E are in the same plane as the center of curvature, and Tq is the radius of the equipotential surface between the hemispheres. If electrons of energy E = eVo are injected at S along the equipotential surface, they will be focused at Eif ... [Pg.13]

Equations (7-66) and (7-67), or related versions, have been used by Hupes and Jencks and by Castro and co-workers to account for curvature. The quantity p/(S defines the center of eurvature of the plot and is expected to occur when the Y>Ka of the nucleophile is equal to the p/( of the leaving group." For weaker nucleophiles pKa < p/(S), breakdown of the tetrahedral intermediate will be rate determining, because the leaving group X is a stronger nucleophile than is N , so 2 < -li if, however, p/( > p/(S, the nucleophilic attack is rate determining. [Pg.353]

Mechanism 2 of Figure 8-122B becomes apparent when the flow recirculation on the tray increases with increasing underflow clearance. The curvature of the column wall influences the movement of the liquid toward the center. High underflow clearance does not even out maldistribution due to backup where the irregular flow pattern enters into the tray below. This allows flow separation to occur on the downcomer floor, and leads to enhanced retrograde flow. [Pg.177]

The radius of curvature R of a plane curve at any point P is the distance along the normal (the perpendicular to the tangent to the curve at point P) on the concave side of the curve to the center of curvature (Figure 1-33). If the equation of the curve is y = f(x)... [Pg.39]

For a spherical mirror the conjugate points lie on top of each other at the center of curvature (COC). Light emitted from the COC of the spherical mirror will focus back onto the COC without any additional system aberration. [Pg.41]

The first environmental problem encountered would be air turbulence. The light travels a 200 m path from center of curvature to the mirror and back. To give an example of the potential problem, assume the temperature of the air... [Pg.99]

A nearly perfect diverging wavefront would exit the test plate appearing as though it came from a source 100 m away. A segment would be positioned so that its mean center of curvature was coincident with that virtual source 100 m away. In the worst case in our example, the un-equal air path would be about 4 m rather than 204 m. Interference would take place between the wavefront reflected off the 100 m radius side of the test plate and the segment. The roughly 3 m back to the source and beamsplitter is common path and will not affect the interference pattern. [Pg.101]

This monomer concentration Ma in the formalism of the quasi-homogeneous approximation, unlike M a, refers to the whole volume of the two-phase system. The aforementioned quantities are connected by the simple relationship Ma = flM a where y01 stands for the volume fraction of the a-th phase in miniemulsion. An analogous relation, Ra = sdaR a, exists between the concentrations Ra of the a-th type active centers in the entire system and those R a in the surface layer of the a-th phase. This layer thickness da has the scale of average spatial size of the a-th type block, which hereafter is presumed to be small as compared to the average radius of miniemulsion drops. Apparently, in this case, the curvature of the interphase surface can be neg-... [Pg.182]

A continuous source can be used for atomic absorption, but since only the center part of the band of wavelengths passed by the slit will be absorbed (due to the sharp line nature of atomic absorption), sensitivity will be sacrificed, and the calibration curve will not be linear. This curvature is because even at high concentrations, only a portion of the radiation passing through the slit will be absorbed, and the limiting absorbance will approach a finite value rather than infinity. With a sharp line source, the entire width of the source radiation is absorbed and so the absorption follows Beer s law. A continuous source works best with the alkali metals because their absorption lines are broader than for most other elements. Specificity is not as great with a continuous source because nearby absorbing lines or molecular absorption bands will absorb part of the source. [Pg.84]

Given the thinness of a diffusion flamelet, it is possible to neglect as a first approximation curvature effects, and to establish a local coordinate system centered at the reaction interface. By definition, X is chosen to be normal to the reaction surface. Furthermore, because the reaction zone is thin compared with the Kolmogorov scale, gradients with respect to X2 and X3 will be much smaller than gradients in the x direction (i.e., the curvature is small).112 Thus, as shown in Fig. 5.18, the scalar fields will be locally onedimensional. [Pg.221]

Concentric Having a common center of curvature or symmetry, [nih]... [Pg.64]


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See also in sourсe #XX -- [ Pg.84 ]




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Center of curvature

Curvatures

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