Thickness fringes

Fiq. 7. (a) Conventional reaction vessel for preparation and use of thick evaporated metal film catalysts (b) reaction vessel for preparation and use of thick, fringe-free evaporated metal film catalysts. 

Work with ultrathin and thick fringe-free platinum films has shown that not only does the product distribution change with catalyst structure, but the specific rate of raction (per unit platinum area) changes also (30). The data in Fig. 12 for the reaction of 2-methylpentane and n-hexane show a decrease in the specific rate with increasing particle size. 

Thick fringe-free polycrystalline Pt film, deposited 273°C massive metal 0.37 5.0 8.4 22 7.5... 

As discussed in Chapter 3, the interference (thickness) fringes can be nsed as a very direct method of layer thickness measurement. We note that the period is... 

Figure 8.2 Oscillations in the 20L ctr intensity at L = 0.5 from evolution of thickness fringes during addition of 9 unit cells to 1-unit-cell-thick PbTiOs film. Vertical dashed lines indicate beginning and end of growth.

Figure 3.19. Thickness fringes in a wedge-shaped crystal of quartz oriented at the exact Bragg angle (f=0) for g=10ll. (a) Bright held, (b) Dark field.

Figure 4.14. Calculated curves showing 7o(a) and /g(a) as a function of thickness z for = 0. These curves correspond to the intensity of thickness fringes in a wedge-shaped crystal in BF and DF, respectively. Note the decrease in the fringe contrast with increasing thickness. tg/tg = 0.05 and (From Hirsch et al.

Figure 8.19. BF image of a Dauphine twin boundary in a wedge-shaped crystal at =0 for g = 10Tl. Note the change in spacing of the thickness fringes across the twin boundary.

Thickness fringes on which is superimposed a fine structure consisting of an array of parallel lines, as at boundary B in Figure 8.32(a,c) and as at boundary C in Figure 8.32(a,b,c). At some places along B the individual lines of the fine structure are clearly identified as single... 

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