Geometric corrugation

The de Broglie wavelength of thermal He atoms is comparable with the interatomic distances of surfaces and adsorbed layers. Thus, from measurements of the angular positions of the diffraction peaks the size and orientation of the 2D unit cell, i.e. the structure of the outermost layer, can be straightforwardly determined. Analysis of the peak intensities yields the potential corrugation, which usually reflects the geometrical arrangement of the atoms within the 2D unit celP. 

For corrugated heat exchangers, extensive information is available in the literature (37 42) these studies have shown that the major geometric parameter is the... 

Another innovative way to modeling of columns equipped with corrugated sheet structured packings is based on the hydrodynamic analogy between complex process hydrodynamics present in real industrial separations and geometrically simpler flow patterns. 

Modulation superimposed on the component layers will substantially influence the interlayer match and sometimes cause deviations from the simple situations described above. It may be of a chemical nature, i.e. ordered substitutions or ordered metal vacancies, but sometimes also geometrical a wave-like modulation or corrugation as a result of the chemical variations. Such modulations are apparently the reason for the small deviations between the respective T and H subcell axes in the majority of cylmdrites of the deviations of the subcell axes in Phase away... 

In all but the densest structures (i.e., those of smallest corrugation amplitude and highest specific geometric surface area), convection is a significantly more important transfer mechanism than molecular diffusion or conduction in the substrate. It is thus important that these structures be installed in the manner illustrated in Fig. 2, since convective transfer takes place in one plane only in any one element length. 

Fig. 9. STM image (10x4 nm, V.j. = -2.2mV, /.j. = 0.5nA) of the NiAl(l 10) surface annealed at 700°C. Only one type of atom is visible as protrusion with a corrugation of 20 - 25 pm. As ab initio calculations show [51], this species is Al. The experimental corrugation coincides with the buckling found by LEED (Al atoms are geometrically 22 pm higher [48]) and is therefore explained as topographic contrast.

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