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Shadow, geometrical

The Incident Ion beam Intensity can be measured, and there are several tabulations of cross-section calculations. ( ) Also, the analyzer parameters, T, D, and d6 can be determined. The three aspects of this equation, which are not well understood nor easily determined. Include the number of atoms of a particular kind, the Ion survival probability, and the shadowing or geometric term. The first quantity Is quite often that which you would like to determine. The second two are often difficult to separate. Shadowing can be particularly Important when trying to observe second layer effect or when trying to determine the location of adsorbates.( ) However, shadowing for polycrystalline samples, though Important, Is very difficult to deal with quantitatively. [Pg.137]

We can think of these representations as shadows of hypercubes on 2-D pieces of paper. Luckily, we don t have to build the object to compute what its shadow would look like. (The computer code I used to create these forms is listed in Appendix I.) Projections of higher-dimensional worlds have stimulated many traditional artists to produce geometrical representations with startling symmetries and complexities (Figs. 4.18 to 4.20). [Pg.105]

Therefore, Cext is a well-defined observable quantity we measure U with and without the particle interposed between source and detector. Because Cext is inherently positive, the effect of the particle is to reduce the detector area by Cext this, then, is the interpretation of Cext as an area. In the language of geometrical optics we would say that the particle casts a shadow of area Cext However, as stated previously, this shadow can be considerably greater—or much less—than the particle s geometrical shadow. We note from (3.33) that Cext is the maximum observable extinction. The scattering term fi(D) X =0/k2 cannot be greater than Csca and is positive therefore, the observed extinction Cext lies within the limits... [Pg.75]

We now consider the properties of the moment free energy with the (chain number) density p0 retained as an extra moment. This provides additional geometrical insight into the properties of polydisperse chains (while for the numerical determination of the CPC and shadow curve, the above one-moment free energy is preferable). To construct the two-moment free energy, we proceed as before. The family (39) is now... [Pg.307]

The Shadow-XY fraction is a geometric descriptor related to the breadth of a molecule (Rohr-baugh and Jurs 1987). This is consistent with our observation that substitution of a bulky group at 7a and lip position of H2 increased the breadth of a chemical and enhanced ER binding (Fang et al., 2001). [Pg.302]

The distance to the moon. Hipparchus in 130 BCE or thereabouts used the curve of the terrestrial shadow across the moon during eclipses to estimate this in units of earth radii and got roughly the right answer. A geometrical method for determining the ratio of sun distance to moon distance failed, because the lunar orbit is not a circle. [Pg.36]

The geometric limit of the cross section (i.e., a= kR is twice the geometric cross section. This result is, at first, surprising because if we consider only the shadow, o= na. However, edge diffraction also contributes an additional na. ... [Pg.635]

Their properties can be investigated as follows (Pliicker, 1858 Hittorf, J. J. Thomson). If a body is placed in the path of the rays, it is seen to cast a shadow on the fluorescent part of the glass. From the geometrical relations it can be inferred that, the rays producing the shadow spread out in... [Pg.15]


See other pages where Shadow, geometrical is mentioned: [Pg.911]    [Pg.124]    [Pg.529]    [Pg.362]    [Pg.137]    [Pg.138]    [Pg.194]    [Pg.28]    [Pg.294]    [Pg.529]    [Pg.510]    [Pg.270]    [Pg.310]    [Pg.326]    [Pg.340]    [Pg.327]    [Pg.345]    [Pg.27]    [Pg.57]    [Pg.400]    [Pg.31]    [Pg.189]    [Pg.180]    [Pg.125]    [Pg.239]    [Pg.105]    [Pg.115]    [Pg.8]    [Pg.24]    [Pg.430]    [Pg.1]    [Pg.306]    [Pg.307]    [Pg.49]    [Pg.478]    [Pg.1]    [Pg.1249]    [Pg.16]    [Pg.911]    [Pg.691]    [Pg.275]    [Pg.360]   
See also in sourсe #XX -- [ Pg.28 ]




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Geometrical shadowing

Geometrical shadowing

Shadow

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